[clang-tools-extra] Adding Separate OpenMP Offloading Backend to `libcxx/include/__algorithm/pstl_backends` (PR #66968)
Anton Rydahl via cfe-commits
cfe-commits at lists.llvm.org
Mon Oct 23 11:26:30 PDT 2023
https://github.com/AntonRydahl updated https://github.com/llvm/llvm-project/pull/66968
>From b35340e47de896c9933c54ce617538c46cf01488 Mon Sep 17 00:00:00 2001
From: AntonRydahl <rydahl2610 at gmail.com>
Date: Wed, 20 Sep 2023 17:06:10 -0700
Subject: [PATCH 01/26] Adding OpenMP Offloading Backend for C++ Parallel
Algorithms
---
libcxx/CMakeLists.txt | 14 +++
libcxx/include/CMakeLists.txt | 5 +
libcxx/include/__algorithm/pstl_backend.h | 8 ++
.../__algorithm/pstl_backends/gpu_backend.h | 21 +++++
.../pstl_backends/gpu_backends/backend.h | 33 +++++++
.../pstl_backends/gpu_backends/fill.h | 59 ++++++++++++
.../pstl_backends/gpu_backends/for_each.h | 59 ++++++++++++
.../pstl_backends/gpu_backends/omp_offload.h | 91 +++++++++++++++++++
libcxx/include/__config_site.in | 1 +
9 files changed, 291 insertions(+)
create mode 100644 libcxx/include/__algorithm/pstl_backends/gpu_backend.h
create mode 100644 libcxx/include/__algorithm/pstl_backends/gpu_backends/backend.h
create mode 100644 libcxx/include/__algorithm/pstl_backends/gpu_backends/fill.h
create mode 100644 libcxx/include/__algorithm/pstl_backends/gpu_backends/for_each.h
create mode 100644 libcxx/include/__algorithm/pstl_backends/gpu_backends/omp_offload.h
diff --git a/libcxx/CMakeLists.txt b/libcxx/CMakeLists.txt
index bb2898b799bcef9..43d2a448de79584 100644
--- a/libcxx/CMakeLists.txt
+++ b/libcxx/CMakeLists.txt
@@ -290,6 +290,8 @@ option(LIBCXX_HAS_WIN32_THREAD_API "Ignore auto-detection and force use of win32
option(LIBCXX_HAS_EXTERNAL_THREAD_API
"Build libc++ with an externalized threading API.
This option may only be set to ON when LIBCXX_ENABLE_THREADS=ON." OFF)
+option(LIBCXX_ENABLE_GPU_OFFLOAD
+ "Build libc++ with support for GPU offload" OFF)
if (LIBCXX_ENABLE_THREADS)
set(LIBCXX_PSTL_CPU_BACKEND "std_thread" CACHE STRING "Which PSTL CPU backend to use")
@@ -297,6 +299,14 @@ else()
set(LIBCXX_PSTL_CPU_BACKEND "serial" CACHE STRING "Which PSTL CPU backend to use")
endif()
+if (NOT DEFINED LIBCXX_PSTL_GPU_BACKEND)
+ if (${LIBCXX_ENABLE_GPU_OFFLOAD})
+ set(LIBCXX_PSTL_GPU_BACKEND "omp_offload" CACHE STRING "Which PSTL GPU backend to use")
+ else()
+ set(LIBCXX_PSTL_GPU_BACKEND "none" CACHE STRING "Which PSTL GPU backend to use")
+ endif()
+endif()
+
# Misc options ----------------------------------------------------------------
# FIXME: Turn -pedantic back ON. It is currently off because it warns
# about #include_next which is used everywhere.
@@ -809,6 +819,10 @@ else()
Valid backends are: serial, std_thread and libdispatch")
endif()
+if (LIBCXX_PSTL_GPU_BACKEND STREQUAL "omp_offload")
+ config_define(1 _LIBCPP_PSTL_GPU_BACKEND_OMP_OFFLOAD)
+endif()
+
if (LIBCXX_ABI_DEFINES)
set(abi_defines)
foreach (abi_define ${LIBCXX_ABI_DEFINES})
diff --git a/libcxx/include/CMakeLists.txt b/libcxx/include/CMakeLists.txt
index 2ec755236dbaee2..a3d72df61a86dde 100644
--- a/libcxx/include/CMakeLists.txt
+++ b/libcxx/include/CMakeLists.txt
@@ -85,6 +85,11 @@ set(files
__algorithm/pstl_backends/cpu_backends/thread.h
__algorithm/pstl_backends/cpu_backends/transform.h
__algorithm/pstl_backends/cpu_backends/transform_reduce.h
+ __algorithm/pstl_backends/gpu_backend.h
+ __algorithm/pstl_backends/gpu_backends/backend.h
+ __algorithm/pstl_backends/gpu_backends/fill.h
+ __algorithm/pstl_backends/gpu_backends/for_each.h
+ __algorithm/pstl_backends/gpu_backends/omp_offload.h
__algorithm/pstl_copy.h
__algorithm/pstl_count.h
__algorithm/pstl_fill.h
diff --git a/libcxx/include/__algorithm/pstl_backend.h b/libcxx/include/__algorithm/pstl_backend.h
index 93372f019031b63..f051e0ce9be13c3 100644
--- a/libcxx/include/__algorithm/pstl_backend.h
+++ b/libcxx/include/__algorithm/pstl_backend.h
@@ -10,6 +10,7 @@
#define _LIBCPP___ALGORITHM_PSTL_BACKEND_H
#include <__algorithm/pstl_backends/cpu_backend.h>
+#include <__algorithm/pstl_backends/gpu_backend.h>
#include <__config>
#include <execution>
@@ -179,10 +180,17 @@ struct __select_backend<std::execution::parallel_policy> {
using type = __cpu_backend_tag;
};
+# if defined(_LIBCPP_PSTL_GPU_BACKEND_OMP_OFFLOAD)
+template <>
+struct __select_backend<std::execution::parallel_unsequenced_policy> {
+ using type = __gpu_backend_tag;
+};
+# else
template <>
struct __select_backend<std::execution::parallel_unsequenced_policy> {
using type = __cpu_backend_tag;
};
+# endif
# else
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backend.h b/libcxx/include/__algorithm/pstl_backends/gpu_backend.h
new file mode 100644
index 000000000000000..46a85f77b5deb99
--- /dev/null
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backend.h
@@ -0,0 +1,21 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_H
+#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_H
+
+#include <__config>
+
+#include <__algorithm/pstl_backends/gpu_backends/backend.h>
+
+#if defined(_LIBCPP_PSTL_GPU_BACKEND_OMP_OFFLOAD)
+#include <__algorithm/pstl_backends/gpu_backends/fill.h>
+#include <__algorithm/pstl_backends/gpu_backends/for_each.h>
+#endif
+
+#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_H
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/backend.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/backend.h
new file mode 100644
index 000000000000000..a8b400afbb94d9d
--- /dev/null
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/backend.h
@@ -0,0 +1,33 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_BACKEND_H
+#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_BACKEND_H
+
+#include <__config>
+#include <cstddef>
+
+#if defined(_LIBCPP_PSTL_GPU_BACKEND_OMP_OFFLOAD)
+# include <__algorithm/pstl_backends/gpu_backends/omp_offload.h>
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+struct __gpu_backend_tag {};
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_BACKEND_H
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/fill.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/fill.h
new file mode 100644
index 000000000000000..5603e18a5d2d3fc
--- /dev/null
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/fill.h
@@ -0,0 +1,59 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKNEDS_FILL_H
+#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKNEDS_FILL_H
+
+#include <__algorithm/fill.h>
+#include <__algorithm/pstl_backends/gpu_backends/backend.h>
+#include <__algorithm/pstl_backends/cpu_backends/backend.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__type_traits/is_execution_policy.h>
+#include <__utility/terminate_on_exception.h>
+#include <stdio.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _Tp>
+_LIBCPP_HIDE_FROM_ABI void
+__pstl_fill(__gpu_backend_tag, _ForwardIterator __first, _ForwardIterator __last, const _Tp& __value) {
+ // It is only safe to execute for_each on the GPU, it the execution policy is
+ // parallel unsequenced, as it is the only execution policy prohibiting throwing
+ // exceptions and allowing SIMD instructions
+ if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
+ std::__par_backend::__parallel_for_simd_val_1(__first, __last - __first, __value);
+ }
+ // Else if the excution policy is parallel, we execute for_each on the CPU instead
+ else if constexpr (__is_parallel_execution_policy_v<_ExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
+ std::__terminate_on_exception([&] {
+ __par_backend::__parallel_for(
+ __first, __last, [&__value](_ForwardIterator __brick_first, _ForwardIterator __brick_last) {
+ std::__pstl_fill<__remove_parallel_policy_t<_ExecutionPolicy>>(
+ __cpu_backend_tag{}, __brick_first, __brick_last, __value);
+ });
+ });
+ // Else we execute for_each in serial
+ } else {
+ std::fill(__first, __last, __value);
+ }
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKNEDS_FILL_H
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/for_each.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/for_each.h
new file mode 100644
index 000000000000000..20486d83863f420
--- /dev/null
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/for_each.h
@@ -0,0 +1,59 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKNEDS_FOR_EACH_H
+#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKNEDS_FOR_EACH_H
+
+#include <__algorithm/for_each.h>
+#include <__algorithm/pstl_backends/gpu_backends/backend.h>
+#include <__algorithm/pstl_backends/cpu_backends/backend.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__type_traits/is_execution_policy.h>
+#include <__utility/terminate_on_exception.h>
+#include <stdio.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _Functor>
+_LIBCPP_HIDE_FROM_ABI void
+__pstl_for_each(__gpu_backend_tag, _ForwardIterator __first, _ForwardIterator __last, _Functor __func) {
+ // It is only safe to execute for_each on the GPU, it the execution policy is
+ // parallel unsequenced, as it is the only execution policy prohibiting throwing
+ // exceptions and allowing SIMD instructions
+ if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
+ std::__par_backend::__parallel_for_simd_1(__first, __last - __first, __func);
+ }
+ // Else if the excution policy is parallel, we execute for_each on the CPU instead
+ else if constexpr (__is_parallel_execution_policy_v<_ExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
+ std::__terminate_on_exception([&] {
+ std::__par_backend::__parallel_for(
+ __first, __last, [__func](_ForwardIterator __brick_first, _ForwardIterator __brick_last) {
+ std::__pstl_for_each<__remove_parallel_policy_t<_ExecutionPolicy>>(
+ __cpu_backend_tag{}, __brick_first, __brick_last, __func);
+ });
+ });
+ // Else we execute for_each in serial
+ } else {
+ std::for_each(__first, __last, __func);
+ }
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKNEDS_FOR_EACH_H
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/omp_offload.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/omp_offload.h
new file mode 100644
index 000000000000000..840118dbec5057c
--- /dev/null
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/omp_offload.h
@@ -0,0 +1,91 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_CPU_BACKENDS_OMP_OFFLOAD_H
+#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_CPU_BACKENDS_OMP_OFFLOAD_H
+
+#include <__assert>
+#include <__config>
+#include <__utility/move.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+namespace __par_backend {
+inline namespace __omp_gpu_backend {
+
+// In OpenMP, we need to extract the pointer for the underlying data for data
+// structures like std::vector and std::array to be able to map the data to the
+// device.
+
+template <typename T>
+_LIBCPP_HIDE_FROM_ABI inline T __omp_extract_base_ptr(T p) {
+ return p;
+}
+
+template <typename T>
+_LIBCPP_HIDE_FROM_ABI inline T __omp_extract_base_ptr(std::__wrap_iter<T> w) {
+ std::pointer_traits<std::__wrap_iter<T>> PT;
+ return PT.to_address(w);
+}
+
+// Applying function or lambda in a loop
+
+template <class _Iterator, class _DifferenceType, class _Function>
+_LIBCPP_HIDE_FROM_ABI _Iterator __omp_parallel_for_simd_1(_Iterator __first, _DifferenceType __n, _Function __f) noexcept {
+ #pragma omp target teams distribute parallel for simd map(tofrom:__first[0:__n])
+ for (_DifferenceType __i = 0; __i < __n; ++__i)
+ __f(__first[__i]);
+
+ return __first + __n;
+}
+
+// Extracting the underlying pointer
+
+template <class _Iterator, class _DifferenceType, class _Function>
+_LIBCPP_HIDE_FROM_ABI _Iterator __parallel_for_simd_1(_Iterator __first, _DifferenceType __n, _Function __f) noexcept {
+ __omp_parallel_for_simd_1(__omp_gpu_backend::__omp_extract_base_ptr(__first), __n, __f);
+ return __first + __n;
+}
+
+// Assigning a value in a loop
+
+template <class _Index, class _DifferenceType, class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Index __omp_parallel_for_simd_val_1(_Index __first, _DifferenceType __n, const _Tp& __value) noexcept {
+ #pragma omp target teams distribute parallel for simd map(tofrom:__first[0:__n]) map(to:__value)
+ for (_DifferenceType __i = 0; __i < __n; ++__i)
+ __first[__i] = __value;
+
+ return __first + __n;
+}
+
+template <class _Index, class _DifferenceType, class _Tp>
+_LIBCPP_HIDE_FROM_ABI _Index __parallel_for_simd_val_1(_Index __first, _DifferenceType __n, const _Tp& __value) noexcept {
+ __omp_parallel_for_simd_val_1(__omp_gpu_backend::__omp_extract_base_ptr(__first), __n, __value);
+ return __first + __n;
+}
+
+} // namespace __omp_gpu_backend
+} // namespace __par_backend
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && && _LIBCPP_STD_VER >= 17
+
+_LIBCPP_POP_MACROS
+
+#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_CPU_BACKENDS_OMP_OFFLOAD_H
diff --git a/libcxx/include/__config_site.in b/libcxx/include/__config_site.in
index c85cbcd02c441b9..e0edddce3afc3ff 100644
--- a/libcxx/include/__config_site.in
+++ b/libcxx/include/__config_site.in
@@ -34,6 +34,7 @@
#cmakedefine _LIBCPP_PSTL_CPU_BACKEND_SERIAL
#cmakedefine _LIBCPP_PSTL_CPU_BACKEND_THREAD
#cmakedefine _LIBCPP_PSTL_CPU_BACKEND_LIBDISPATCH
+#cmakedefine _LIBCPP_PSTL_GPU_BACKEND_OMP_OFFLOAD
// Hardening.
#cmakedefine01 _LIBCPP_ENABLE_HARDENED_MODE_DEFAULT
>From af5ddf7709e44435c3b0b15421aa9cfc24b49e84 Mon Sep 17 00:00:00 2001
From: antonrydahl <rydahl2610 at gmail.com>
Date: Wed, 20 Sep 2023 17:48:25 -0700
Subject: [PATCH 02/26] Clang formatting OpenMP backend for parallel algorithms
---
libcxx/include/__algorithm/pstl_backend.h | 6 +++---
.../include/__algorithm/pstl_backends/gpu_backend.h | 4 ++--
.../__algorithm/pstl_backends/gpu_backends/fill.h | 12 ++++++------
.../pstl_backends/gpu_backends/for_each.h | 12 ++++++------
.../pstl_backends/gpu_backends/omp_offload.h | 13 ++++++++-----
5 files changed, 25 insertions(+), 22 deletions(-)
diff --git a/libcxx/include/__algorithm/pstl_backend.h b/libcxx/include/__algorithm/pstl_backend.h
index f051e0ce9be13c3..47f5191b48517ba 100644
--- a/libcxx/include/__algorithm/pstl_backend.h
+++ b/libcxx/include/__algorithm/pstl_backend.h
@@ -180,17 +180,17 @@ struct __select_backend<std::execution::parallel_policy> {
using type = __cpu_backend_tag;
};
-# if defined(_LIBCPP_PSTL_GPU_BACKEND_OMP_OFFLOAD)
+# if defined(_LIBCPP_PSTL_GPU_BACKEND_OMP_OFFLOAD)
template <>
struct __select_backend<std::execution::parallel_unsequenced_policy> {
using type = __gpu_backend_tag;
};
-# else
+# else
template <>
struct __select_backend<std::execution::parallel_unsequenced_policy> {
using type = __cpu_backend_tag;
};
-# endif
+# endif
# else
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backend.h b/libcxx/include/__algorithm/pstl_backends/gpu_backend.h
index 46a85f77b5deb99..7237036156a1bf3 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backend.h
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backend.h
@@ -14,8 +14,8 @@
#include <__algorithm/pstl_backends/gpu_backends/backend.h>
#if defined(_LIBCPP_PSTL_GPU_BACKEND_OMP_OFFLOAD)
-#include <__algorithm/pstl_backends/gpu_backends/fill.h>
-#include <__algorithm/pstl_backends/gpu_backends/for_each.h>
+# include <__algorithm/pstl_backends/gpu_backends/fill.h>
+# include <__algorithm/pstl_backends/gpu_backends/for_each.h>
#endif
#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_H
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/fill.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/fill.h
index 5603e18a5d2d3fc..32926da87e2a083 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/fill.h
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/fill.h
@@ -10,8 +10,8 @@
#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKNEDS_FILL_H
#include <__algorithm/fill.h>
-#include <__algorithm/pstl_backends/gpu_backends/backend.h>
#include <__algorithm/pstl_backends/cpu_backends/backend.h>
+#include <__algorithm/pstl_backends/gpu_backends/backend.h>
#include <__config>
#include <__iterator/concepts.h>
#include <__type_traits/is_execution_policy.h>
@@ -29,16 +29,16 @@ _LIBCPP_BEGIN_NAMESPACE_STD
template <class _ExecutionPolicy, class _ForwardIterator, class _Tp>
_LIBCPP_HIDE_FROM_ABI void
__pstl_fill(__gpu_backend_tag, _ForwardIterator __first, _ForwardIterator __last, const _Tp& __value) {
- // It is only safe to execute for_each on the GPU, it the execution policy is
+ // It is only safe to execute for_each on the GPU, it the execution policy is
// parallel unsequenced, as it is the only execution policy prohibiting throwing
// exceptions and allowing SIMD instructions
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
- __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
+ __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
std::__par_backend::__parallel_for_simd_val_1(__first, __last - __first, __value);
}
// Else if the excution policy is parallel, we execute for_each on the CPU instead
- else if constexpr (__is_parallel_execution_policy_v<_ExecutionPolicy> &&
- __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
+ else if constexpr (__is_parallel_execution_policy_v<_ExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
std::__terminate_on_exception([&] {
__par_backend::__parallel_for(
__first, __last, [&__value](_ForwardIterator __brick_first, _ForwardIterator __brick_last) {
@@ -46,7 +46,7 @@ __pstl_fill(__gpu_backend_tag, _ForwardIterator __first, _ForwardIterator __last
__cpu_backend_tag{}, __brick_first, __brick_last, __value);
});
});
- // Else we execute for_each in serial
+ // Else we execute for_each in serial
} else {
std::fill(__first, __last, __value);
}
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/for_each.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/for_each.h
index 20486d83863f420..14de2af8e4a15c6 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/for_each.h
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/for_each.h
@@ -10,8 +10,8 @@
#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKNEDS_FOR_EACH_H
#include <__algorithm/for_each.h>
-#include <__algorithm/pstl_backends/gpu_backends/backend.h>
#include <__algorithm/pstl_backends/cpu_backends/backend.h>
+#include <__algorithm/pstl_backends/gpu_backends/backend.h>
#include <__config>
#include <__iterator/concepts.h>
#include <__type_traits/is_execution_policy.h>
@@ -29,16 +29,16 @@ _LIBCPP_BEGIN_NAMESPACE_STD
template <class _ExecutionPolicy, class _ForwardIterator, class _Functor>
_LIBCPP_HIDE_FROM_ABI void
__pstl_for_each(__gpu_backend_tag, _ForwardIterator __first, _ForwardIterator __last, _Functor __func) {
- // It is only safe to execute for_each on the GPU, it the execution policy is
+ // It is only safe to execute for_each on the GPU, it the execution policy is
// parallel unsequenced, as it is the only execution policy prohibiting throwing
// exceptions and allowing SIMD instructions
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
- __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
+ __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
std::__par_backend::__parallel_for_simd_1(__first, __last - __first, __func);
}
// Else if the excution policy is parallel, we execute for_each on the CPU instead
- else if constexpr (__is_parallel_execution_policy_v<_ExecutionPolicy> &&
- __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
+ else if constexpr (__is_parallel_execution_policy_v<_ExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
std::__terminate_on_exception([&] {
std::__par_backend::__parallel_for(
__first, __last, [__func](_ForwardIterator __brick_first, _ForwardIterator __brick_last) {
@@ -46,7 +46,7 @@ __pstl_for_each(__gpu_backend_tag, _ForwardIterator __first, _ForwardIterator __
__cpu_backend_tag{}, __brick_first, __brick_last, __func);
});
});
- // Else we execute for_each in serial
+ // Else we execute for_each in serial
} else {
std::for_each(__first, __last, __func);
}
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/omp_offload.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/omp_offload.h
index 840118dbec5057c..4baa4e7f65859d1 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/omp_offload.h
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/omp_offload.h
@@ -46,8 +46,9 @@ _LIBCPP_HIDE_FROM_ABI inline T __omp_extract_base_ptr(std::__wrap_iter<T> w) {
// Applying function or lambda in a loop
template <class _Iterator, class _DifferenceType, class _Function>
-_LIBCPP_HIDE_FROM_ABI _Iterator __omp_parallel_for_simd_1(_Iterator __first, _DifferenceType __n, _Function __f) noexcept {
- #pragma omp target teams distribute parallel for simd map(tofrom:__first[0:__n])
+_LIBCPP_HIDE_FROM_ABI _Iterator
+__omp_parallel_for_simd_1(_Iterator __first, _DifferenceType __n, _Function __f) noexcept {
+# pragma omp target teams distribute parallel for simd map(tofrom : __first[0 : __n])
for (_DifferenceType __i = 0; __i < __n; ++__i)
__f(__first[__i]);
@@ -65,8 +66,9 @@ _LIBCPP_HIDE_FROM_ABI _Iterator __parallel_for_simd_1(_Iterator __first, _Differ
// Assigning a value in a loop
template <class _Index, class _DifferenceType, class _Tp>
-_LIBCPP_HIDE_FROM_ABI _Index __omp_parallel_for_simd_val_1(_Index __first, _DifferenceType __n, const _Tp& __value) noexcept {
- #pragma omp target teams distribute parallel for simd map(tofrom:__first[0:__n]) map(to:__value)
+_LIBCPP_HIDE_FROM_ABI _Index
+__omp_parallel_for_simd_val_1(_Index __first, _DifferenceType __n, const _Tp& __value) noexcept {
+# pragma omp target teams distribute parallel for simd map(tofrom : __first[0 : __n]) map(to : __value)
for (_DifferenceType __i = 0; __i < __n; ++__i)
__first[__i] = __value;
@@ -74,7 +76,8 @@ _LIBCPP_HIDE_FROM_ABI _Index __omp_parallel_for_simd_val_1(_Index __first, _Diff
}
template <class _Index, class _DifferenceType, class _Tp>
-_LIBCPP_HIDE_FROM_ABI _Index __parallel_for_simd_val_1(_Index __first, _DifferenceType __n, const _Tp& __value) noexcept {
+_LIBCPP_HIDE_FROM_ABI _Index
+__parallel_for_simd_val_1(_Index __first, _DifferenceType __n, const _Tp& __value) noexcept {
__omp_parallel_for_simd_val_1(__omp_gpu_backend::__omp_extract_base_ptr(__first), __n, __value);
return __first + __n;
}
>From 57abf3062c4e559fddd6bf173d415212b9f92e43 Mon Sep 17 00:00:00 2001
From: AntonRydahl <rydahl2610 at gmail.com>
Date: Thu, 21 Sep 2023 12:50:17 -0700
Subject: [PATCH 03/26] Making PSTL GPU backend depend on CMake options rather
than command line options
---
libcxx/CMakeLists.txt | 11 +++++------
libcxx/include/__algorithm/pstl_backend.h | 2 +-
.../include/__algorithm/pstl_backends/gpu_backend.h | 2 +-
.../__algorithm/pstl_backends/gpu_backends/backend.h | 8 ++++++--
libcxx/include/__config_site.in | 1 +
5 files changed, 14 insertions(+), 10 deletions(-)
diff --git a/libcxx/CMakeLists.txt b/libcxx/CMakeLists.txt
index 43d2a448de79584..7aa47caa1ca335a 100644
--- a/libcxx/CMakeLists.txt
+++ b/libcxx/CMakeLists.txt
@@ -299,12 +299,10 @@ else()
set(LIBCXX_PSTL_CPU_BACKEND "serial" CACHE STRING "Which PSTL CPU backend to use")
endif()
-if (NOT DEFINED LIBCXX_PSTL_GPU_BACKEND)
- if (${LIBCXX_ENABLE_GPU_OFFLOAD})
- set(LIBCXX_PSTL_GPU_BACKEND "omp_offload" CACHE STRING "Which PSTL GPU backend to use")
- else()
- set(LIBCXX_PSTL_GPU_BACKEND "none" CACHE STRING "Which PSTL GPU backend to use")
- endif()
+if (${LIBCXX_ENABLE_GPU_OFFLOAD})
+ set(LIBCXX_PSTL_GPU_BACKEND "omp_offload" CACHE STRING "Which PSTL GPU backend to use")
+else()
+ set(LIBCXX_PSTL_GPU_BACKEND "none" CACHE STRING "Which PSTL GPU backend to use")
endif()
# Misc options ----------------------------------------------------------------
@@ -819,6 +817,7 @@ else()
Valid backends are: serial, std_thread and libdispatch")
endif()
+config_define_if(LIBCXX_ENABLE_GPU_OFFLOAD _LIBCPP_PSTL_GPU_OFFLOAD)
if (LIBCXX_PSTL_GPU_BACKEND STREQUAL "omp_offload")
config_define(1 _LIBCPP_PSTL_GPU_BACKEND_OMP_OFFLOAD)
endif()
diff --git a/libcxx/include/__algorithm/pstl_backend.h b/libcxx/include/__algorithm/pstl_backend.h
index 47f5191b48517ba..0df8847fd33589a 100644
--- a/libcxx/include/__algorithm/pstl_backend.h
+++ b/libcxx/include/__algorithm/pstl_backend.h
@@ -180,7 +180,7 @@ struct __select_backend<std::execution::parallel_policy> {
using type = __cpu_backend_tag;
};
-# if defined(_LIBCPP_PSTL_GPU_BACKEND_OMP_OFFLOAD)
+# if defined(_LIBCPP_PSTL_GPU_OFFLOAD)
template <>
struct __select_backend<std::execution::parallel_unsequenced_policy> {
using type = __gpu_backend_tag;
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backend.h b/libcxx/include/__algorithm/pstl_backends/gpu_backend.h
index 7237036156a1bf3..d2a814b441224a5 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backend.h
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backend.h
@@ -13,7 +13,7 @@
#include <__algorithm/pstl_backends/gpu_backends/backend.h>
-#if defined(_LIBCPP_PSTL_GPU_BACKEND_OMP_OFFLOAD)
+#if defined(_LIBCPP_PSTL_GPU_OFFLOAD)
# include <__algorithm/pstl_backends/gpu_backends/fill.h>
# include <__algorithm/pstl_backends/gpu_backends/for_each.h>
#endif
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/backend.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/backend.h
index a8b400afbb94d9d..a03ad35d8d2ae3e 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/backend.h
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/backend.h
@@ -12,8 +12,12 @@
#include <__config>
#include <cstddef>
-#if defined(_LIBCPP_PSTL_GPU_BACKEND_OMP_OFFLOAD)
-# include <__algorithm/pstl_backends/gpu_backends/omp_offload.h>
+#if defined(_LIBCPP_PSTL_GPU_OFFLOAD)
+# if defined(_LIBCPP_PSTL_GPU_BACKEND_OMP_OFFLOAD)
+# include <__algorithm/pstl_backends/gpu_backends/omp_offload.h>
+# else
+# error Invalid PSTL GPU backend
+# endif
#endif
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
diff --git a/libcxx/include/__config_site.in b/libcxx/include/__config_site.in
index e0edddce3afc3ff..e7fb4f423079333 100644
--- a/libcxx/include/__config_site.in
+++ b/libcxx/include/__config_site.in
@@ -35,6 +35,7 @@
#cmakedefine _LIBCPP_PSTL_CPU_BACKEND_THREAD
#cmakedefine _LIBCPP_PSTL_CPU_BACKEND_LIBDISPATCH
#cmakedefine _LIBCPP_PSTL_GPU_BACKEND_OMP_OFFLOAD
+#cmakedefine _LIBCPP_PSTL_GPU_OFFLOAD
// Hardening.
#cmakedefine01 _LIBCPP_ENABLE_HARDENED_MODE_DEFAULT
>From 51d9ed5702a46ac604bafbe2f707033639f86706 Mon Sep 17 00:00:00 2001
From: AntonRydahl <rydahl2610 at gmail.com>
Date: Thu, 21 Sep 2023 17:07:58 -0700
Subject: [PATCH 04/26] Added OpenMP offloaded version of std::transform
---
libcxx/include/CMakeLists.txt | 1 +
.../__algorithm/pstl_backends/gpu_backend.h | 1 +
.../pstl_backends/gpu_backends/omp_offload.h | 119 +++++++++++++++++-
.../pstl_backends/gpu_backends/transform.h | 117 +++++++++++++++++
4 files changed, 233 insertions(+), 5 deletions(-)
create mode 100644 libcxx/include/__algorithm/pstl_backends/gpu_backends/transform.h
diff --git a/libcxx/include/CMakeLists.txt b/libcxx/include/CMakeLists.txt
index a3d72df61a86dde..66e54cfbf1780ee 100644
--- a/libcxx/include/CMakeLists.txt
+++ b/libcxx/include/CMakeLists.txt
@@ -90,6 +90,7 @@ set(files
__algorithm/pstl_backends/gpu_backends/fill.h
__algorithm/pstl_backends/gpu_backends/for_each.h
__algorithm/pstl_backends/gpu_backends/omp_offload.h
+ __algorithm/pstl_backends/gpu_backends/transform.h
__algorithm/pstl_copy.h
__algorithm/pstl_count.h
__algorithm/pstl_fill.h
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backend.h b/libcxx/include/__algorithm/pstl_backends/gpu_backend.h
index d2a814b441224a5..dac26592dac5c1f 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backend.h
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backend.h
@@ -16,6 +16,7 @@
#if defined(_LIBCPP_PSTL_GPU_OFFLOAD)
# include <__algorithm/pstl_backends/gpu_backends/fill.h>
# include <__algorithm/pstl_backends/gpu_backends/for_each.h>
+# include <__algorithm/pstl_backends/gpu_backends/transform.h>
#endif
#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_H
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/omp_offload.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/omp_offload.h
index 4baa4e7f65859d1..69221cbb8519233 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/omp_offload.h
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/omp_offload.h
@@ -28,6 +28,17 @@ _LIBCPP_BEGIN_NAMESPACE_STD
namespace __par_backend {
inline namespace __omp_gpu_backend {
+// Checking if a pointer is in a range
+template <typename T1, typename T2, typename T3>
+_LIBCPP_HIDE_FROM_ABI inline bool __omp_in_ptr_range(T1 a, T2 p, T3 b) {
+ return false;
+}
+
+template <typename T>
+_LIBCPP_HIDE_FROM_ABI inline bool __omp_in_ptr_range(T* a, T* p, T* b) {
+ return std::less_equal<T*>{}(a, p) && std::less<T*>{}(p, b);
+}
+
// In OpenMP, we need to extract the pointer for the underlying data for data
// structures like std::vector and std::array to be able to map the data to the
// device.
@@ -43,12 +54,16 @@ _LIBCPP_HIDE_FROM_ABI inline T __omp_extract_base_ptr(std::__wrap_iter<T> w) {
return PT.to_address(w);
}
+//===----------------------------------------------------------------------===//
+// Templates for one iterator
+//===----------------------------------------------------------------------===//
+
// Applying function or lambda in a loop
template <class _Iterator, class _DifferenceType, class _Function>
_LIBCPP_HIDE_FROM_ABI _Iterator
-__omp_parallel_for_simd_1(_Iterator __first, _DifferenceType __n, _Function __f) noexcept {
-# pragma omp target teams distribute parallel for simd map(tofrom : __first[0 : __n])
+__omp_parallel_for_simd_1(_Iterator __first, _DifferenceType __n, _Function __f, const int __device = 0) noexcept {
+# pragma omp target teams distribute parallel for simd map(tofrom : __first[0 : __n]) device(__device)
for (_DifferenceType __i = 0; __i < __n; ++__i)
__f(__first[__i]);
@@ -66,9 +81,10 @@ _LIBCPP_HIDE_FROM_ABI _Iterator __parallel_for_simd_1(_Iterator __first, _Differ
// Assigning a value in a loop
template <class _Index, class _DifferenceType, class _Tp>
-_LIBCPP_HIDE_FROM_ABI _Index
-__omp_parallel_for_simd_val_1(_Index __first, _DifferenceType __n, const _Tp& __value) noexcept {
-# pragma omp target teams distribute parallel for simd map(tofrom : __first[0 : __n]) map(to : __value)
+_LIBCPP_HIDE_FROM_ABI _Index __omp_parallel_for_simd_val_1(
+ _Index __first, _DifferenceType __n, const _Tp& __value, const int __device = 0) noexcept {
+# pragma omp target teams distribute parallel for simd map(from : __first[0 : __n]) map(always, to : __value) \
+ device(__device)
for (_DifferenceType __i = 0; __i < __n; ++__i)
__first[__i] = __value;
@@ -82,6 +98,99 @@ __parallel_for_simd_val_1(_Index __first, _DifferenceType __n, const _Tp& __valu
return __first + __n;
}
+//===----------------------------------------------------------------------===//
+// Templates for two iterators
+//===----------------------------------------------------------------------===//
+
+template <class _Iterator1, class _DifferenceType, class _Iterator2, class _Function>
+_LIBCPP_HIDE_FROM_ABI _Iterator1 __omp_parallel_for_simd_2(
+ _Iterator1 __first1, _DifferenceType __n, _Iterator2 __first2, _Function __f, const int __device = 0) noexcept {
+ if ((!std::is_same<_Iterator1, _Iterator2>::value) ||
+ (std::is_same<_Iterator1, _Iterator2>::value &&
+ !__omp_gpu_backend::__omp_in_ptr_range(__first1, __first2, __first1 + __n))) {
+# pragma omp target teams distribute parallel for simd map(to : __first1[0 : __n]) map(from : __first2[0 : __n]) \
+ device(__device)
+ for (_DifferenceType __i = 0; __i < __n; ++__i)
+ __f(__first1[__i], __first2[__i]);
+ return __first1 + __n;
+ }
+# pragma omp target teams distribute parallel for simd map(tofrom : __first1[0 : __n], __first2[0 : __n]) \
+ device(__device)
+ for (_DifferenceType __i = 0; __i < __n; ++__i)
+ __f(__first1[__i], __first2[__i]);
+
+ return __first1 + __n;
+}
+
+// Extracting the underlying pointer
+
+template <class _Iterator1, class _DifferenceType, class _Iterator2, class _Function>
+_LIBCPP_HIDE_FROM_ABI _Iterator1
+__parallel_for_simd_2(_Iterator1 __first1, _DifferenceType __n, _Iterator2 __first2, _Function __f) noexcept {
+ __omp_parallel_for_simd_2(
+ __omp_gpu_backend::__omp_extract_base_ptr(__first1),
+ __n,
+ __omp_gpu_backend::__omp_extract_base_ptr(__first2),
+ __f);
+ return __first1 + __n;
+}
+
+//===----------------------------------------------------------------------===//
+// Templates for three iterator
+//===----------------------------------------------------------------------===//
+
+template <class _Iterator1, class _DifferenceType, class _Iterator2, class _Iterator3, class _Function>
+_LIBCPP_HIDE_FROM_ABI _Iterator1 __omp_parallel_for_simd_3(
+ _Iterator1 __first1,
+ _DifferenceType __n,
+ _Iterator2 __first2,
+ _Iterator3 __first3,
+ _Function __f,
+ const int __device = 0) noexcept {
+ // It may be that __first3 is in the interval [__first1+__n) or [__firt2+__n)
+ // It is, however, undefined behavior to compare two pointers that do not
+ // point to the same object or are not the same type.
+ // If we can prove that __first3 is not in any of the ranges [__first1+__n)
+ // or [__firt2+__n), it is safe to reduce the amount of data copied to and
+ // from the device
+ constexpr bool are_not_same_type =
+ !std::is_same<_Iterator1, _Iterator2>::value && !std::is_same<_Iterator1, _Iterator3>::value;
+ const bool no_overlap_13 =
+ std::is_same<_Iterator1, _Iterator3>::value &&
+ !__omp_gpu_backend::__omp_in_ptr_range(__first1, __first3, __first1 + __n);
+ const bool no_overlap_23 =
+ std::is_same<_Iterator2, _Iterator3>::value &&
+ !__omp_gpu_backend::__omp_in_ptr_range(__first2, __first3, __first2 + __n);
+ if (are_not_same_type || (no_overlap_13 && no_overlap_23)) {
+# pragma omp target teams distribute parallel for simd map(to : __first1[0 : __n], __first2[0 : __n]) \
+ map(from : __first3[0 : __n]) device(__device)
+ for (_DifferenceType __i = 0; __i < __n; ++__i)
+ __f(__first1[__i], __first2[__i], __first3[__i]);
+ return __first1 + __n;
+ }
+ // In the general case, we have to map all data to and from the device
+# pragma omp target teams distribute parallel for simd map( \
+ tofrom : __first1[0 : __n], __first2[0 : __n], __first3[0 : __n]) device(__device)
+ for (_DifferenceType __i = 0; __i < __n; ++__i)
+ __f(__first1[__i], __first2[__i], __first3[__i]);
+
+ return __first1 + __n;
+}
+
+// Extracting the underlying pointer
+
+template <class _Iterator1, class _DifferenceType, class _Iterator2, class _Iterator3, class _Function>
+_LIBCPP_HIDE_FROM_ABI _Iterator1 __parallel_for_simd_3(
+ _Iterator1 __first1, _DifferenceType __n, _Iterator2 __first2, _Iterator3 __first3, _Function __f) noexcept {
+ __omp_parallel_for_simd_3(
+ __omp_gpu_backend::__omp_extract_base_ptr(__first1),
+ __n,
+ __omp_gpu_backend::__omp_extract_base_ptr(__first2),
+ __omp_gpu_backend::__omp_extract_base_ptr(__first3),
+ __f);
+ return __first1 + __n;
+}
+
} // namespace __omp_gpu_backend
} // namespace __par_backend
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform.h
new file mode 100644
index 000000000000000..03eba11a3f5f52b
--- /dev/null
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform.h
@@ -0,0 +1,117 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_TRANSFORM_H
+#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_TRANSFORM_H
+
+#include <__algorithm/pstl_backends/cpu_backends/backend.h>
+#include <__algorithm/pstl_backends/gpu_backends/backend.h>
+#include <__algorithm/transform.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__type_traits/enable_if.h>
+#include <__type_traits/is_execution_policy.h>
+#include <__type_traits/remove_cvref.h>
+#include <__utility/terminate_on_exception.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _ForwardOutIterator, class _UnaryOperation>
+_LIBCPP_HIDE_FROM_ABI _ForwardOutIterator __pstl_transform(
+ __gpu_backend_tag,
+ _ForwardIterator __first,
+ _ForwardIterator __last,
+ _ForwardOutIterator __result,
+ _UnaryOperation __op) {
+ if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator>::value &&
+ __has_random_access_iterator_category_or_concept<_ForwardOutIterator>::value) {
+ return std::__par_backend::__parallel_for_simd_2(
+ __first,
+ __last - __first,
+ __result,
+ [&](__iter_reference<_ForwardIterator> __in_value, __iter_reference<_ForwardOutIterator> __out_value) {
+ __out_value = __op(__in_value);
+ });
+ } else if constexpr (__is_parallel_execution_policy_v<_ExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator>::value &&
+ __has_random_access_iterator_category_or_concept<_ForwardOutIterator>::value) {
+ std::__terminate_on_exception([&] {
+ std::__par_backend::__parallel_for(
+ __first, __last, [__op, __first, __result](_ForwardIterator __brick_first, _ForwardIterator __brick_last) {
+ return std::__pstl_transform<__remove_parallel_policy_t<_ExecutionPolicy>>(
+ __cpu_backend_tag{}, __brick_first, __brick_last, __result + (__brick_first - __first), __op);
+ });
+ });
+ return __result + (__last - __first);
+ } else {
+ return std::transform(__first, __last, __result, __op);
+ }
+}
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator1,
+ class _ForwardIterator2,
+ class _ForwardOutIterator,
+ class _BinaryOperation,
+ enable_if_t<is_execution_policy_v<__remove_cvref_t<_ExecutionPolicy>>, int> = 0>
+_LIBCPP_HIDE_FROM_ABI _ForwardOutIterator __pstl_transform(
+ __gpu_backend_tag,
+ _ForwardIterator1 __first1,
+ _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2,
+ _ForwardOutIterator __result,
+ _BinaryOperation __op) {
+ if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator1>::value &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator2>::value &&
+ __has_random_access_iterator_category_or_concept<_ForwardOutIterator>::value) {
+ return std::__par_backend::__parallel_for_simd_3(
+ __first1,
+ __last1 - __first1,
+ __first2,
+ __result,
+ [&](__iter_reference<_ForwardIterator1> __in1,
+ __iter_reference<_ForwardIterator2> __in2,
+ __iter_reference<_ForwardOutIterator> __out_value) { __out_value = __op(__in1, __in2); });
+ } else if constexpr (__is_parallel_execution_policy_v<_ExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator1>::value &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator2>::value &&
+ __has_random_access_iterator_category_or_concept<_ForwardOutIterator>::value) {
+ std::__terminate_on_exception([&] {
+ std::__par_backend::__parallel_for(
+ __first1,
+ __last1,
+ [__op, __first1, __first2, __result](_ForwardIterator1 __brick_first, _ForwardIterator1 __brick_last) {
+ return std::__pstl_transform<__remove_parallel_policy_t<_ExecutionPolicy>>(
+ __cpu_backend_tag{},
+ __brick_first,
+ __brick_last,
+ __first2 + (__brick_first - __first1),
+ __result + (__brick_first - __first1),
+ __op);
+ });
+ });
+ return __result + (__last1 - __first1);
+ } else {
+ return std::transform(__first1, __last1, __first2, __result, __op);
+ }
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_TRANSFORM_H
>From 33b61efe005cb12247cdf89ce7b7a4c5ca849f5b Mon Sep 17 00:00:00 2001
From: AntonRydahl <rydahl2610 at gmail.com>
Date: Fri, 22 Sep 2023 11:55:53 -0700
Subject: [PATCH 05/26] Changing lambdas to capture by value in std::transform
for GPUs
---
.../__algorithm/pstl_backends/gpu_backends/transform.h | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform.h
index 03eba11a3f5f52b..7fcfde44aaaa7a6 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform.h
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform.h
@@ -38,11 +38,13 @@ _LIBCPP_HIDE_FROM_ABI _ForwardOutIterator __pstl_transform(
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__has_random_access_iterator_category_or_concept<_ForwardIterator>::value &&
__has_random_access_iterator_category_or_concept<_ForwardOutIterator>::value) {
+ // While the CPU backend captures by reference, [&], that is not valid when
+ // offloading to the GPU. Therefore we must capture by value, [=].
return std::__par_backend::__parallel_for_simd_2(
__first,
__last - __first,
__result,
- [&](__iter_reference<_ForwardIterator> __in_value, __iter_reference<_ForwardOutIterator> __out_value) {
+ [=](__iter_reference<_ForwardIterator> __in_value, __iter_reference<_ForwardOutIterator> __out_value) {
__out_value = __op(__in_value);
});
} else if constexpr (__is_parallel_execution_policy_v<_ExecutionPolicy> &&
@@ -78,12 +80,14 @@ _LIBCPP_HIDE_FROM_ABI _ForwardOutIterator __pstl_transform(
__has_random_access_iterator_category_or_concept<_ForwardIterator1>::value &&
__has_random_access_iterator_category_or_concept<_ForwardIterator2>::value &&
__has_random_access_iterator_category_or_concept<_ForwardOutIterator>::value) {
+ // While the CPU backend captures by reference, [&], that is not valid when
+ // offloading to the GPU. Therefore we must capture by value, [=].
return std::__par_backend::__parallel_for_simd_3(
__first1,
__last1 - __first1,
__first2,
__result,
- [&](__iter_reference<_ForwardIterator1> __in1,
+ [=](__iter_reference<_ForwardIterator1> __in1,
__iter_reference<_ForwardIterator2> __in2,
__iter_reference<_ForwardOutIterator> __out_value) { __out_value = __op(__in1, __in2); });
} else if constexpr (__is_parallel_execution_policy_v<_ExecutionPolicy> &&
>From 065f52d742a4e490b9b0441b9d997fe8e4268a8a Mon Sep 17 00:00:00 2001
From: AntonRydahl <rydahl2610 at gmail.com>
Date: Mon, 25 Sep 2023 13:13:39 -0700
Subject: [PATCH 06/26] GPU Offloading Implementation of std::transform_reduce
---
libcxx/include/CMakeLists.txt | 1 +
.../__algorithm/pstl_backends/gpu_backend.h | 1 +
.../pstl_backends/gpu_backends/omp_offload.h | 113 ++++++++++++++
.../gpu_backends/transform_reduce.h | 147 ++++++++++++++++++
4 files changed, 262 insertions(+)
create mode 100644 libcxx/include/__algorithm/pstl_backends/gpu_backends/transform_reduce.h
diff --git a/libcxx/include/CMakeLists.txt b/libcxx/include/CMakeLists.txt
index 66e54cfbf1780ee..ea00d3fdaea2924 100644
--- a/libcxx/include/CMakeLists.txt
+++ b/libcxx/include/CMakeLists.txt
@@ -91,6 +91,7 @@ set(files
__algorithm/pstl_backends/gpu_backends/for_each.h
__algorithm/pstl_backends/gpu_backends/omp_offload.h
__algorithm/pstl_backends/gpu_backends/transform.h
+ __algorithm/pstl_backends/gpu_backends/transform_reduce.h
__algorithm/pstl_copy.h
__algorithm/pstl_count.h
__algorithm/pstl_fill.h
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backend.h b/libcxx/include/__algorithm/pstl_backends/gpu_backend.h
index dac26592dac5c1f..ea7f39dea905474 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backend.h
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backend.h
@@ -17,6 +17,7 @@
# include <__algorithm/pstl_backends/gpu_backends/fill.h>
# include <__algorithm/pstl_backends/gpu_backends/for_each.h>
# include <__algorithm/pstl_backends/gpu_backends/transform.h>
+# include <__algorithm/pstl_backends/gpu_backends/transform_reduce.h>
#endif
#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_H
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/omp_offload.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/omp_offload.h
index 69221cbb8519233..d1cc6133f8e0876 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/omp_offload.h
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/omp_offload.h
@@ -191,6 +191,119 @@ _LIBCPP_HIDE_FROM_ABI _Iterator1 __parallel_for_simd_3(
return __first1 + __n;
}
+//===----------------------------------------------------------------------===//
+// Templates for reductions
+//===----------------------------------------------------------------------===//
+
+// General case
+
+# define __PSTL_OMP_SIMD_1_REDUCTION(omp_op, std_op) \
+ template <class _Iterator, \
+ class _DifferenceType, \
+ typename _Tp, \
+ typename _BinaryOperationType, \
+ typename _UnaryOperation, \
+ __enable_if_t<is_arithmetic_v<_Tp>, int> = 0 > \
+ _LIBCPP_HIDE_FROM_ABI _Tp __omp_parallel_for_simd_reduction_1( \
+ _Iterator __first, \
+ _DifferenceType __n, \
+ _Tp __init, \
+ std_op<_BinaryOperationType> __reduce, \
+ _UnaryOperation __transform, \
+ const int __device = 0) noexcept { \
+_PSTL_PRAGMA(omp target teams distribute parallel for simd reduction(omp_op:__init) map(to : __first[0 : __n]) device(__device)) \
+ for (_DifferenceType __i = 0; __i < __n; ++__i) \
+ __init = __reduce(__init, __transform(__first[__i])); \
+ return __init; \
+ }
+
+# define __PSTL_OMP_SIMD_2_REDUCTION(omp_op, std_op) \
+ template <class _Iterator1, \
+ class _Iterator2, \
+ class _DifferenceType, \
+ typename _Tp, \
+ typename _BinaryOperationType, \
+ typename _UnaryOperation, \
+ __enable_if_t<is_arithmetic_v<_Tp>, int> = 0 > \
+ _LIBCPP_HIDE_FROM_ABI _Tp __omp_parallel_for_simd_reduction_2( \
+ _Iterator1 __first1, \
+ _Iterator2 __first2, \
+ _DifferenceType __n, \
+ _Tp __init, \
+ std_op<_BinaryOperationType> __reduce, \
+ _UnaryOperation __transform, \
+ const int __device = 0) noexcept { \
+_PSTL_PRAGMA(omp target teams distribute parallel for simd reduction(omp_op:__init) map(to : __first1[0 : __n], __first2[0 : __n]) device(__device)) \
+ for (_DifferenceType __i = 0; __i < __n; ++__i) \
+ __init = __reduce(__init, __transform(__first1[__i], __first2[__i])); \
+ return __init; \
+ }
+
+# define __PSTL_OMP_SIMD_REDUCTION(omp_op, std_op) \
+ __PSTL_OMP_SIMD_1_REDUCTION(omp_op, std_op) \
+ __PSTL_OMP_SIMD_2_REDUCTION(omp_op, std_op)
+
+// Addition
+__PSTL_OMP_SIMD_REDUCTION(+, std::plus)
+
+// Subtraction
+__PSTL_OMP_SIMD_REDUCTION(-, std::minus)
+
+// Multiplication
+__PSTL_OMP_SIMD_REDUCTION(*, std::multiplies)
+
+// Logical and
+__PSTL_OMP_SIMD_REDUCTION(&&, std::logical_and)
+
+// Logical or
+__PSTL_OMP_SIMD_REDUCTION(||, std::logical_or)
+
+// Bitwise and
+__PSTL_OMP_SIMD_REDUCTION(&, std::bit_and)
+
+// Bitwise or
+__PSTL_OMP_SIMD_REDUCTION(|, std::bit_or)
+
+// Bitwise xor
+__PSTL_OMP_SIMD_REDUCTION(^, std::bit_xor)
+
+// Extracting the underlying pointers
+
+template <class _Iterator, class _DifferenceType, typename _Tp, typename _BinaryOperation, typename _UnaryOperation >
+_LIBCPP_HIDE_FROM_ABI _Tp __parallel_for_simd_reduction_1(
+ _Iterator __first,
+ _DifferenceType __n,
+ _Tp __init,
+ _BinaryOperation __reduce,
+ _UnaryOperation __transform,
+ const int __device = 0) noexcept {
+ return __omp_parallel_for_simd_reduction_1(
+ __omp_gpu_backend::__omp_extract_base_ptr(__first), __n, __init, __reduce, __transform);
+}
+
+template <class _Iterator1,
+ class _Iterator2,
+ class _DifferenceType,
+ typename _Tp,
+ typename _BinaryOperation,
+ typename _UnaryOperation >
+_LIBCPP_HIDE_FROM_ABI _Tp __parallel_for_simd_reduction_2(
+ _Iterator1 __first1,
+ _Iterator2 __first2,
+ _DifferenceType __n,
+ _Tp __init,
+ _BinaryOperation __reduce,
+ _UnaryOperation __transform,
+ const int __device = 0) noexcept {
+ return __omp_parallel_for_simd_reduction_2(
+ __omp_gpu_backend::__omp_extract_base_ptr(__first1),
+ __omp_gpu_backend::__omp_extract_base_ptr(__first2),
+ __n,
+ __init,
+ __reduce,
+ __transform);
+}
+
} // namespace __omp_gpu_backend
} // namespace __par_backend
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform_reduce.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform_reduce.h
new file mode 100644
index 000000000000000..43e5631aef04afb
--- /dev/null
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform_reduce.h
@@ -0,0 +1,147 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_TRANSFORM_REDUCE_H
+#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_TRANSFORM_REDUCE_H
+
+#include <__algorithm/pstl_backends/cpu_backends/backend.h>
+#include <__algorithm/pstl_backends/gpu_backends/backend.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__numeric/transform_reduce.h>
+#include <__type_traits/is_arithmetic.h>
+#include <__type_traits/is_execution_policy.h>
+#include <__type_traits/operation_traits.h>
+#include <__utility/move.h>
+#include <__utility/terminate_on_exception.h>
+#include <new>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+//===----------------------------------------------------------------------===//
+// Two input iterators
+//===----------------------------------------------------------------------===//
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator1,
+ class _ForwardIterator2,
+ class _Tp,
+ class _BinaryOperation1,
+ class _BinaryOperation2>
+_LIBCPP_HIDE_FROM_ABI _Tp __pstl_transform_reduce(
+ __gpu_backend_tag,
+ _ForwardIterator1 __first1,
+ _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2,
+ _Tp __init,
+ _BinaryOperation1 __reduce,
+ _BinaryOperation2 __transform) {
+ if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator1>::value &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator2>::value) {
+ return std::__par_backend::__parallel_for_simd_reduction_2(
+ std::move(__first1),
+ std::move(__first2),
+ __last1 - __first1,
+ std::move(__init),
+ std::move(__reduce),
+ [=](__iter_reference<_ForwardIterator1> __in_value_1, __iter_reference<_ForwardIterator1> __in_value_2) {
+ return __transform(__in_value_1, __in_value_2);
+ });
+ } else if constexpr (__is_parallel_execution_policy_v<_ExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator1>::value &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator2>::value) {
+ return std::__terminate_on_exception([&] {
+ return __par_backend::__parallel_transform_reduce(
+ __first1,
+ std::move(__last1),
+ [__first1, __first2, __transform](_ForwardIterator1 __iter) {
+ return __transform(*__iter, *(__first2 + (__iter - __first1)));
+ },
+ std::move(__init),
+ std::move(__reduce),
+ [__first1, __first2, __reduce, __transform](
+ _ForwardIterator1 __brick_first, _ForwardIterator1 __brick_last, _Tp __brick_init) {
+ return std::__pstl_transform_reduce<__remove_parallel_policy_t<_ExecutionPolicy>>(
+ __cpu_backend_tag{},
+ __brick_first,
+ std::move(__brick_last),
+ __first2 + (__brick_first - __first1),
+ std::move(__brick_init),
+ std::move(__reduce),
+ std::move(__transform));
+ });
+ });
+ } else {
+ return std::transform_reduce(
+ std::move(__first1),
+ std::move(__last1),
+ std::move(__first2),
+ std::move(__init),
+ std::move(__reduce),
+ std::move(__transform));
+ }
+}
+
+//===----------------------------------------------------------------------===//
+// One input iterator
+//===----------------------------------------------------------------------===//
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _Tp, class _BinaryOperation, class _UnaryOperation>
+_LIBCPP_HIDE_FROM_ABI _Tp __pstl_transform_reduce(
+ __gpu_backend_tag,
+ _ForwardIterator __first,
+ _ForwardIterator __last,
+ _Tp __init,
+ _BinaryOperation __reduce,
+ _UnaryOperation __transform) {
+ if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
+ return std::__par_backend::__parallel_for_simd_reduction_1(
+ std::move(__first),
+ __last - __first,
+ std::move(__init),
+ std::move(__reduce),
+ [=](__iter_reference<_ForwardIterator> __in_value) { return __transform(__in_value); });
+ } else if constexpr (__is_parallel_execution_policy_v<_ExecutionPolicy> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
+ return std::__terminate_on_exception([&] {
+ return __par_backend::__parallel_transform_reduce(
+ std::move(__first),
+ std::move(__last),
+ [__transform](_ForwardIterator __iter) { return __transform(*__iter); },
+ std::move(__init),
+ __reduce,
+ [__transform, __reduce](auto __brick_first, auto __brick_last, _Tp __brick_init) {
+ return std::__pstl_transform_reduce<__remove_parallel_policy_t<_ExecutionPolicy>>(
+ __cpu_backend_tag{},
+ std::move(__brick_first),
+ std::move(__brick_last),
+ std::move(__brick_init),
+ std::move(__reduce),
+ std::move(__transform));
+ });
+ });
+ } else {
+ return std::transform_reduce(
+ std::move(__first), std::move(__last), std::move(__init), std::move(__reduce), std::move(__transform));
+ }
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_TRANSFORM_REDUCE_H
>From 67ecdee8fc6fcf94873486858445cf1a7b37c7dc Mon Sep 17 00:00:00 2001
From: AntonRydahl <rydahl2610 at gmail.com>
Date: Tue, 26 Sep 2023 19:55:12 -0700
Subject: [PATCH 07/26] Fixed almost all test cases that failed during ninja
check-cxx
---
libcxx/include/CMakeLists.txt | 4 +
.../__algorithm/pstl_backends/gpu_backend.h | 4 +
.../pstl_backends/gpu_backends/any_of.h | 41 +++++++
.../pstl_backends/gpu_backends/fill.h | 20 +---
.../pstl_backends/gpu_backends/find_if.h | 44 ++++++++
.../pstl_backends/gpu_backends/for_each.h | 17 +--
.../pstl_backends/gpu_backends/merge.h | 51 +++++++++
.../pstl_backends/gpu_backends/omp_offload.h | 94 +++++++++-------
.../pstl_backends/gpu_backends/stable_sort.h | 38 +++++++
.../pstl_backends/gpu_backends/transform.h | 61 ++--------
.../gpu_backends/transform_reduce.h | 105 ++++++------------
11 files changed, 292 insertions(+), 187 deletions(-)
create mode 100644 libcxx/include/__algorithm/pstl_backends/gpu_backends/any_of.h
create mode 100644 libcxx/include/__algorithm/pstl_backends/gpu_backends/find_if.h
create mode 100644 libcxx/include/__algorithm/pstl_backends/gpu_backends/merge.h
create mode 100644 libcxx/include/__algorithm/pstl_backends/gpu_backends/stable_sort.h
diff --git a/libcxx/include/CMakeLists.txt b/libcxx/include/CMakeLists.txt
index ea00d3fdaea2924..8dfd4e2f26ecf8f 100644
--- a/libcxx/include/CMakeLists.txt
+++ b/libcxx/include/CMakeLists.txt
@@ -86,10 +86,14 @@ set(files
__algorithm/pstl_backends/cpu_backends/transform.h
__algorithm/pstl_backends/cpu_backends/transform_reduce.h
__algorithm/pstl_backends/gpu_backend.h
+ __algorithm/pstl_backends/gpu_backends/any_of.h
__algorithm/pstl_backends/gpu_backends/backend.h
__algorithm/pstl_backends/gpu_backends/fill.h
+ __algorithm/pstl_backends/gpu_backends/find_if.h
__algorithm/pstl_backends/gpu_backends/for_each.h
+ __algorithm/pstl_backends/gpu_backends/merge.h
__algorithm/pstl_backends/gpu_backends/omp_offload.h
+ __algorithm/pstl_backends/gpu_backends/stable_sort.h
__algorithm/pstl_backends/gpu_backends/transform.h
__algorithm/pstl_backends/gpu_backends/transform_reduce.h
__algorithm/pstl_copy.h
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backend.h b/libcxx/include/__algorithm/pstl_backends/gpu_backend.h
index ea7f39dea905474..f41332fbf9f6d42 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backend.h
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backend.h
@@ -14,8 +14,12 @@
#include <__algorithm/pstl_backends/gpu_backends/backend.h>
#if defined(_LIBCPP_PSTL_GPU_OFFLOAD)
+# include <__algorithm/pstl_backends/gpu_backends/any_of.h>
# include <__algorithm/pstl_backends/gpu_backends/fill.h>
+# include <__algorithm/pstl_backends/gpu_backends/find_if.h>
# include <__algorithm/pstl_backends/gpu_backends/for_each.h>
+# include <__algorithm/pstl_backends/gpu_backends/merge.h>
+# include <__algorithm/pstl_backends/gpu_backends/stable_sort.h>
# include <__algorithm/pstl_backends/gpu_backends/transform.h>
# include <__algorithm/pstl_backends/gpu_backends/transform_reduce.h>
#endif
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/any_of.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/any_of.h
new file mode 100644
index 000000000000000..8d911de55dcd685
--- /dev/null
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/any_of.h
@@ -0,0 +1,41 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_ANY_OF_H
+#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_ANY_OF_H
+
+#include <__algorithm/any_of.h>
+#include <__algorithm/find_if.h>
+#include <__algorithm/pstl_backends/cpu_backends/backend.h>
+#include <__algorithm/pstl_backends/gpu_backends/backend.h>
+#include <__atomic/atomic.h>
+#include <__atomic/memory_order.h>
+#include <__config>
+#include <__functional/operations.h>
+#include <__iterator/concepts.h>
+#include <__type_traits/is_execution_policy.h>
+#include <__utility/pair.h>
+#include <__utility/terminate_on_exception.h>
+#include <cstdint>
+
+#if !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _Predicate>
+_LIBCPP_HIDE_FROM_ABI bool
+__pstl_any_of(__gpu_backend_tag, _ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) {
+ // TODO: Implement GPU backend
+ return std::__pstl_any_of<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __pred);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_ANY_OF_H
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/fill.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/fill.h
index 32926da87e2a083..8dc6bc6a6179c0e 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/fill.h
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/fill.h
@@ -14,6 +14,7 @@
#include <__algorithm/pstl_backends/gpu_backends/backend.h>
#include <__config>
#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
#include <__type_traits/is_execution_policy.h>
#include <__utility/terminate_on_exception.h>
#include <stdio.h>
@@ -33,23 +34,12 @@ __pstl_fill(__gpu_backend_tag, _ForwardIterator __first, _ForwardIterator __last
// parallel unsequenced, as it is the only execution policy prohibiting throwing
// exceptions and allowing SIMD instructions
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
- __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
+ __has_random_access_iterator_category_or_concept<_ForwardIterator>::value &&
+ __libcpp_is_contiguous_iterator<_ForwardIterator>::value) {
std::__par_backend::__parallel_for_simd_val_1(__first, __last - __first, __value);
}
- // Else if the excution policy is parallel, we execute for_each on the CPU instead
- else if constexpr (__is_parallel_execution_policy_v<_ExecutionPolicy> &&
- __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
- std::__terminate_on_exception([&] {
- __par_backend::__parallel_for(
- __first, __last, [&__value](_ForwardIterator __brick_first, _ForwardIterator __brick_last) {
- std::__pstl_fill<__remove_parallel_policy_t<_ExecutionPolicy>>(
- __cpu_backend_tag{}, __brick_first, __brick_last, __value);
- });
- });
- // Else we execute for_each in serial
- } else {
- std::fill(__first, __last, __value);
- }
+ // Otherwise, we execute for_each on the CPU instead
+ return std::__pstl_fill<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __value);
}
_LIBCPP_END_NAMESPACE_STD
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/find_if.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/find_if.h
new file mode 100644
index 000000000000000..2d34938f92dff38
--- /dev/null
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/find_if.h
@@ -0,0 +1,44 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_FIND_IF_H
+#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_FIND_IF_H
+
+#include <__algorithm/find_if.h>
+#include <__algorithm/pstl_backends/cpu_backends/backend.h>
+#include <__algorithm/pstl_backends/gpu_backends/backend.h>
+#include <__atomic/atomic.h>
+#include <__config>
+#include <__functional/operations.h>
+#include <__iterator/concepts.h>
+#include <__iterator/iterator_traits.h>
+#include <__type_traits/is_execution_policy.h>
+#include <__utility/pair.h>
+#include <__utility/terminate_on_exception.h>
+#include <cstddef>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _ExecutionPolicy, class _ForwardIterator, class _Predicate>
+_LIBCPP_HIDE_FROM_ABI _ForwardIterator
+__pstl_find_if(__gpu_backend_tag, _ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) {
+ // TODO: Implement the GPU backend
+ return std::__pstl_find_if<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __pred);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_FIND_IF_H
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/for_each.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/for_each.h
index 14de2af8e4a15c6..23c8da27e64ae3b 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/for_each.h
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/for_each.h
@@ -33,23 +33,12 @@ __pstl_for_each(__gpu_backend_tag, _ForwardIterator __first, _ForwardIterator __
// parallel unsequenced, as it is the only execution policy prohibiting throwing
// exceptions and allowing SIMD instructions
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
- __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
+ __has_random_access_iterator_category_or_concept<_ForwardIterator>::value &&
+ __libcpp_is_contiguous_iterator<_ForwardIterator>::value) {
std::__par_backend::__parallel_for_simd_1(__first, __last - __first, __func);
}
// Else if the excution policy is parallel, we execute for_each on the CPU instead
- else if constexpr (__is_parallel_execution_policy_v<_ExecutionPolicy> &&
- __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
- std::__terminate_on_exception([&] {
- std::__par_backend::__parallel_for(
- __first, __last, [__func](_ForwardIterator __brick_first, _ForwardIterator __brick_last) {
- std::__pstl_for_each<__remove_parallel_policy_t<_ExecutionPolicy>>(
- __cpu_backend_tag{}, __brick_first, __brick_last, __func);
- });
- });
- // Else we execute for_each in serial
- } else {
- std::for_each(__first, __last, __func);
- }
+ return std::__pstl_for_each<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __func);
}
_LIBCPP_END_NAMESPACE_STD
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/merge.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/merge.h
new file mode 100644
index 000000000000000..bc947ebb27ac7f0
--- /dev/null
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/merge.h
@@ -0,0 +1,51 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_MERGE_H
+#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_MERGE_H
+
+#include <__algorithm/merge.h>
+#include <__algorithm/pstl_backends/cpu_backends/backend.h>
+#include <__algorithm/pstl_backends/gpu_backends/backend.h>
+#include <__config>
+#include <__iterator/concepts.h>
+#include <__type_traits/is_execution_policy.h>
+#include <__utility/move.h>
+#include <__utility/terminate_on_exception.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _ExecutionPolicy,
+ class _ForwardIterator1,
+ class _ForwardIterator2,
+ class _ForwardOutIterator,
+ class _Comp>
+_LIBCPP_HIDE_FROM_ABI _ForwardOutIterator __pstl_merge(
+ __gpu_backend_tag,
+ _ForwardIterator1 __first1,
+ _ForwardIterator1 __last1,
+ _ForwardIterator2 __first2,
+ _ForwardIterator2 __last2,
+ _ForwardOutIterator __result,
+ _Comp __comp) {
+ // TODO: Implement GPU backend
+ return std::__pstl_merge<_ExecutionPolicy>(
+ __cpu_backend_tag{}, __first1, __last1, __first2, __last2, __result, __comp);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_MERGE_H
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/omp_offload.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/omp_offload.h
index d1cc6133f8e0876..36acafd448ec003 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/omp_offload.h
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/omp_offload.h
@@ -11,9 +11,19 @@
#include <__assert>
#include <__config>
+#include <__functional/operations.h>
+#include <__iterator/wrap_iter.h>
+#include <__memory/addressof.h>
+#include <__memory/pointer_traits.h>
+#include <__type_traits/is_pointer.h>
+#include <__type_traits/is_same.h>
#include <__utility/move.h>
#include <cstddef>
+// is_same
+
+// __libcpp_is_contiguous_iterator
+
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
@@ -30,27 +40,33 @@ inline namespace __omp_gpu_backend {
// Checking if a pointer is in a range
template <typename T1, typename T2, typename T3>
-_LIBCPP_HIDE_FROM_ABI inline bool __omp_in_ptr_range(T1 a, T2 p, T3 b) {
+_LIBCPP_HIDE_FROM_ABI inline bool __omp_in_ptr_range(T1, T2, T3) {
return false;
}
-template <typename T>
-_LIBCPP_HIDE_FROM_ABI inline bool __omp_in_ptr_range(T* a, T* p, T* b) {
- return std::less_equal<T*>{}(a, p) && std::less<T*>{}(p, b);
+template <typename _Tp>
+_LIBCPP_HIDE_FROM_ABI inline bool __omp_in_ptr_range(_Tp* a, _Tp* p, _Tp* b) {
+ return std::less_equal<_Tp*>{}(a, p) && std::less<_Tp*>{}(p, b);
}
// In OpenMP, we need to extract the pointer for the underlying data for data
// structures like std::vector and std::array to be able to map the data to the
// device.
-template <typename T>
-_LIBCPP_HIDE_FROM_ABI inline T __omp_extract_base_ptr(T p) {
+template <typename _Tp, std::enable_if<std::is_pointer<_Tp>::value >::type* = 0>
+_LIBCPP_HIDE_FROM_ABI inline _Tp __omp_extract_base_ptr(_Tp p) {
return p;
}
-template <typename T>
-_LIBCPP_HIDE_FROM_ABI inline T __omp_extract_base_ptr(std::__wrap_iter<T> w) {
- std::pointer_traits<std::__wrap_iter<T>> PT;
+template <typename _Tp>
+_LIBCPP_HIDE_FROM_ABI inline auto __omp_extract_base_ptr(_Tp p) {
+ return std::addressof(*p);
+ ;
+}
+
+template <typename _Tp>
+_LIBCPP_HIDE_FROM_ABI inline _Tp __omp_extract_base_ptr(std::__wrap_iter<_Tp> w) {
+ std::pointer_traits<std::__wrap_iter<_Tp>> PT;
return PT.to_address(w);
}
@@ -61,8 +77,8 @@ _LIBCPP_HIDE_FROM_ABI inline T __omp_extract_base_ptr(std::__wrap_iter<T> w) {
// Applying function or lambda in a loop
template <class _Iterator, class _DifferenceType, class _Function>
-_LIBCPP_HIDE_FROM_ABI _Iterator
-__omp_parallel_for_simd_1(_Iterator __first, _DifferenceType __n, _Function __f, const int __device = 0) noexcept {
+_LIBCPP_HIDE_FROM_ABI _Iterator __omp_parallel_for_simd_1(
+ _Iterator __first, _DifferenceType __n, _Function __f, [[maybe_unused]] const int __device = 0) noexcept {
# pragma omp target teams distribute parallel for simd map(tofrom : __first[0 : __n]) device(__device)
for (_DifferenceType __i = 0; __i < __n; ++__i)
__f(__first[__i]);
@@ -82,7 +98,7 @@ _LIBCPP_HIDE_FROM_ABI _Iterator __parallel_for_simd_1(_Iterator __first, _Differ
template <class _Index, class _DifferenceType, class _Tp>
_LIBCPP_HIDE_FROM_ABI _Index __omp_parallel_for_simd_val_1(
- _Index __first, _DifferenceType __n, const _Tp& __value, const int __device = 0) noexcept {
+ _Index __first, _DifferenceType __n, const _Tp& __value, [[maybe_unused]] const int __device = 0) noexcept {
# pragma omp target teams distribute parallel for simd map(from : __first[0 : __n]) map(always, to : __value) \
device(__device)
for (_DifferenceType __i = 0; __i < __n; ++__i)
@@ -104,20 +120,24 @@ __parallel_for_simd_val_1(_Index __first, _DifferenceType __n, const _Tp& __valu
template <class _Iterator1, class _DifferenceType, class _Iterator2, class _Function>
_LIBCPP_HIDE_FROM_ABI _Iterator1 __omp_parallel_for_simd_2(
- _Iterator1 __first1, _DifferenceType __n, _Iterator2 __first2, _Function __f, const int __device = 0) noexcept {
+ _Iterator1 __first1,
+ _DifferenceType __n,
+ _Iterator2 __first2,
+ _Function __f,
+ [[maybe_unused]] const int __device = 0) noexcept {
if ((!std::is_same<_Iterator1, _Iterator2>::value) ||
(std::is_same<_Iterator1, _Iterator2>::value &&
!__omp_gpu_backend::__omp_in_ptr_range(__first1, __first2, __first1 + __n))) {
# pragma omp target teams distribute parallel for simd map(to : __first1[0 : __n]) map(from : __first2[0 : __n]) \
device(__device)
for (_DifferenceType __i = 0; __i < __n; ++__i)
- __f(__first1[__i], __first2[__i]);
+ __first2[__i] = __f(__first1[__i]);
return __first1 + __n;
}
# pragma omp target teams distribute parallel for simd map(tofrom : __first1[0 : __n], __first2[0 : __n]) \
device(__device)
for (_DifferenceType __i = 0; __i < __n; ++__i)
- __f(__first1[__i], __first2[__i]);
+ __first2[__i] = __f(__first1[__i]);
return __first1 + __n;
}
@@ -146,7 +166,7 @@ _LIBCPP_HIDE_FROM_ABI _Iterator1 __omp_parallel_for_simd_3(
_Iterator2 __first2,
_Iterator3 __first3,
_Function __f,
- const int __device = 0) noexcept {
+ [[maybe_unused]] const int __device = 0) noexcept {
// It may be that __first3 is in the interval [__first1+__n) or [__firt2+__n)
// It is, however, undefined behavior to compare two pointers that do not
// point to the same object or are not the same type.
@@ -165,14 +185,14 @@ _LIBCPP_HIDE_FROM_ABI _Iterator1 __omp_parallel_for_simd_3(
# pragma omp target teams distribute parallel for simd map(to : __first1[0 : __n], __first2[0 : __n]) \
map(from : __first3[0 : __n]) device(__device)
for (_DifferenceType __i = 0; __i < __n; ++__i)
- __f(__first1[__i], __first2[__i], __first3[__i]);
+ __first3[__i] = __f(__first1[__i], __first2[__i]);
return __first1 + __n;
}
// In the general case, we have to map all data to and from the device
# pragma omp target teams distribute parallel for simd map( \
tofrom : __first1[0 : __n], __first2[0 : __n], __first3[0 : __n]) device(__device)
for (_DifferenceType __i = 0; __i < __n; ++__i)
- __f(__first1[__i], __first2[__i], __first3[__i]);
+ __first3[__i] = __f(__first1[__i], __first2[__i]);
return __first1 + __n;
}
@@ -197,46 +217,44 @@ _LIBCPP_HIDE_FROM_ABI _Iterator1 __parallel_for_simd_3(
// General case
-# define __PSTL_OMP_SIMD_1_REDUCTION(omp_op, std_op) \
+# define __PSTL_OMP_SIMD_1_REDUCTION(omp_op, std_op) \
template <class _Iterator, \
class _DifferenceType, \
typename _Tp, \
typename _BinaryOperationType, \
- typename _UnaryOperation, \
- __enable_if_t<is_arithmetic_v<_Tp>, int> = 0 > \
+ typename _UnaryOperation> \
_LIBCPP_HIDE_FROM_ABI _Tp __omp_parallel_for_simd_reduction_1( \
_Iterator __first, \
_DifferenceType __n, \
_Tp __init, \
std_op<_BinaryOperationType> __reduce, \
- _UnaryOperation __transform, \
- const int __device = 0) noexcept { \
-_PSTL_PRAGMA(omp target teams distribute parallel for simd reduction(omp_op:__init) map(to : __first[0 : __n]) device(__device)) \
- for (_DifferenceType __i = 0; __i < __n; ++__i) \
- __init = __reduce(__init, __transform(__first[__i])); \
- return __init; \
+ _UnaryOperation __transform/*, \
+ [[maybe_unused]] const int __device = 0*/) noexcept { \
+_PSTL_PRAGMA(omp target teams distribute parallel for simd reduction(omp_op:__init) map(to : __first[0 : __n])) /*device(__device))*/ \
+ for (_DifferenceType __i = 0; __i < __n; ++__i) \
+ __init = __reduce(__init, __transform(__first[__i])); \
+ return __init; \
}
-# define __PSTL_OMP_SIMD_2_REDUCTION(omp_op, std_op) \
+# define __PSTL_OMP_SIMD_2_REDUCTION(omp_op, std_op) \
template <class _Iterator1, \
class _Iterator2, \
class _DifferenceType, \
typename _Tp, \
typename _BinaryOperationType, \
- typename _UnaryOperation, \
- __enable_if_t<is_arithmetic_v<_Tp>, int> = 0 > \
+ typename _UnaryOperation > \
_LIBCPP_HIDE_FROM_ABI _Tp __omp_parallel_for_simd_reduction_2( \
_Iterator1 __first1, \
_Iterator2 __first2, \
_DifferenceType __n, \
_Tp __init, \
std_op<_BinaryOperationType> __reduce, \
- _UnaryOperation __transform, \
- const int __device = 0) noexcept { \
-_PSTL_PRAGMA(omp target teams distribute parallel for simd reduction(omp_op:__init) map(to : __first1[0 : __n], __first2[0 : __n]) device(__device)) \
- for (_DifferenceType __i = 0; __i < __n; ++__i) \
- __init = __reduce(__init, __transform(__first1[__i], __first2[__i])); \
- return __init; \
+ _UnaryOperation __transform/*, \
+ [[maybe_unused]] const int __device = 0*/) noexcept { \
+_PSTL_PRAGMA(omp target teams distribute parallel for simd reduction(omp_op:__init) map(to : __first1[0 : __n], __first2[0 : __n]))/* device(__device))*/ \
+ for (_DifferenceType __i = 0; __i < __n; ++__i) \
+ __init = __reduce(__init, __transform(__first1[__i], __first2[__i])); \
+ return __init; \
}
# define __PSTL_OMP_SIMD_REDUCTION(omp_op, std_op) \
@@ -276,7 +294,7 @@ _LIBCPP_HIDE_FROM_ABI _Tp __parallel_for_simd_reduction_1(
_Tp __init,
_BinaryOperation __reduce,
_UnaryOperation __transform,
- const int __device = 0) noexcept {
+ [[maybe_unused]] const int __device = 0) noexcept {
return __omp_parallel_for_simd_reduction_1(
__omp_gpu_backend::__omp_extract_base_ptr(__first), __n, __init, __reduce, __transform);
}
@@ -294,7 +312,7 @@ _LIBCPP_HIDE_FROM_ABI _Tp __parallel_for_simd_reduction_2(
_Tp __init,
_BinaryOperation __reduce,
_UnaryOperation __transform,
- const int __device = 0) noexcept {
+ [[maybe_unused]] const int __device = 0) noexcept {
return __omp_parallel_for_simd_reduction_2(
__omp_gpu_backend::__omp_extract_base_ptr(__first1),
__omp_gpu_backend::__omp_extract_base_ptr(__first2),
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/stable_sort.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/stable_sort.h
new file mode 100644
index 000000000000000..1760a9fd9fc9d32
--- /dev/null
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/stable_sort.h
@@ -0,0 +1,38 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_STABLE_SORT_H
+#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_STABLE_SORT_H
+
+#include <__algorithm/pstl_backends/cpu_backends/backend.h>
+#include <__algorithm/pstl_backends/gpu_backends/backend.h>
+#include <__algorithm/stable_sort.h>
+#include <__config>
+#include <__type_traits/is_execution_policy.h>
+#include <__utility/terminate_on_exception.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+# pragma GCC system_header
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+template <class _ExecutionPolicy, class _RandomAccessIterator, class _Comp>
+_LIBCPP_HIDE_FROM_ABI void
+__pstl_stable_sort(__gpu_backend_tag, _RandomAccessIterator __first, _RandomAccessIterator __last, _Comp __comp) {
+ // TODO: Implement GPU backend.
+ return __pstl_stable_sort<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __comp);
+}
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
+
+#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_STABLE_SORT_H
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform.h
index 7fcfde44aaaa7a6..10f6e5ff174d675 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform.h
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform.h
@@ -37,30 +37,13 @@ _LIBCPP_HIDE_FROM_ABI _ForwardOutIterator __pstl_transform(
_UnaryOperation __op) {
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__has_random_access_iterator_category_or_concept<_ForwardIterator>::value &&
- __has_random_access_iterator_category_or_concept<_ForwardOutIterator>::value) {
+ __has_random_access_iterator_category_or_concept<_ForwardOutIterator>::value &&
+ __libcpp_is_contiguous_iterator<_ForwardIterator>::value) {
// While the CPU backend captures by reference, [&], that is not valid when
// offloading to the GPU. Therefore we must capture by value, [=].
- return std::__par_backend::__parallel_for_simd_2(
- __first,
- __last - __first,
- __result,
- [=](__iter_reference<_ForwardIterator> __in_value, __iter_reference<_ForwardOutIterator> __out_value) {
- __out_value = __op(__in_value);
- });
- } else if constexpr (__is_parallel_execution_policy_v<_ExecutionPolicy> &&
- __has_random_access_iterator_category_or_concept<_ForwardIterator>::value &&
- __has_random_access_iterator_category_or_concept<_ForwardOutIterator>::value) {
- std::__terminate_on_exception([&] {
- std::__par_backend::__parallel_for(
- __first, __last, [__op, __first, __result](_ForwardIterator __brick_first, _ForwardIterator __brick_last) {
- return std::__pstl_transform<__remove_parallel_policy_t<_ExecutionPolicy>>(
- __cpu_backend_tag{}, __brick_first, __brick_last, __result + (__brick_first - __first), __op);
- });
- });
- return __result + (__last - __first);
- } else {
- return std::transform(__first, __last, __result, __op);
+ return std::__par_backend::__parallel_for_simd_2(__first, __last - __first, __result, __op);
}
+ return std::__pstl_transform<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __result, __op);
}
template <class _ExecutionPolicy,
@@ -79,39 +62,15 @@ _LIBCPP_HIDE_FROM_ABI _ForwardOutIterator __pstl_transform(
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__has_random_access_iterator_category_or_concept<_ForwardIterator1>::value &&
__has_random_access_iterator_category_or_concept<_ForwardIterator2>::value &&
- __has_random_access_iterator_category_or_concept<_ForwardOutIterator>::value) {
+ __has_random_access_iterator_category_or_concept<_ForwardOutIterator>::value &&
+ __libcpp_is_contiguous_iterator<_ForwardIterator1>::value &&
+ __libcpp_is_contiguous_iterator<_ForwardIterator2>::value &&
+ __libcpp_is_contiguous_iterator<_ForwardOutIterator>::value) {
// While the CPU backend captures by reference, [&], that is not valid when
// offloading to the GPU. Therefore we must capture by value, [=].
- return std::__par_backend::__parallel_for_simd_3(
- __first1,
- __last1 - __first1,
- __first2,
- __result,
- [=](__iter_reference<_ForwardIterator1> __in1,
- __iter_reference<_ForwardIterator2> __in2,
- __iter_reference<_ForwardOutIterator> __out_value) { __out_value = __op(__in1, __in2); });
- } else if constexpr (__is_parallel_execution_policy_v<_ExecutionPolicy> &&
- __has_random_access_iterator_category_or_concept<_ForwardIterator1>::value &&
- __has_random_access_iterator_category_or_concept<_ForwardIterator2>::value &&
- __has_random_access_iterator_category_or_concept<_ForwardOutIterator>::value) {
- std::__terminate_on_exception([&] {
- std::__par_backend::__parallel_for(
- __first1,
- __last1,
- [__op, __first1, __first2, __result](_ForwardIterator1 __brick_first, _ForwardIterator1 __brick_last) {
- return std::__pstl_transform<__remove_parallel_policy_t<_ExecutionPolicy>>(
- __cpu_backend_tag{},
- __brick_first,
- __brick_last,
- __first2 + (__brick_first - __first1),
- __result + (__brick_first - __first1),
- __op);
- });
- });
- return __result + (__last1 - __first1);
- } else {
- return std::transform(__first1, __last1, __first2, __result, __op);
+ return std::__par_backend::__parallel_for_simd_3(__first1, __last1 - __first1, __first2, __result, __op);
}
+ return std::__pstl_transform<_ExecutionPolicy>(__cpu_backend_tag{}, __first1, __last1, __first2, __result, __op);
}
_LIBCPP_END_NAMESPACE_STD
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform_reduce.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform_reduce.h
index 43e5631aef04afb..8590dd3d024ea69 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform_reduce.h
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform_reduce.h
@@ -12,9 +12,11 @@
#include <__algorithm/pstl_backends/cpu_backends/backend.h>
#include <__algorithm/pstl_backends/gpu_backends/backend.h>
#include <__config>
+#include <__functional/operations.h>
#include <__iterator/concepts.h>
#include <__iterator/iterator_traits.h>
#include <__numeric/transform_reduce.h>
+#include <__type_traits/integral_constant.h>
#include <__type_traits/is_arithmetic.h>
#include <__type_traits/is_execution_policy.h>
#include <__type_traits/operation_traits.h>
@@ -28,6 +30,25 @@
#if !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
+template <class _T1, class _T2, class _T3>
+struct __is_supported_reduction : std::false_type {};
+
+# define __PSTL_IS_SUPPORTED_REDUCTION(funname) \
+ template <class _Tp> \
+ struct __is_supported_reduction<std::funname<_Tp>, _Tp, _Tp> : std::true_type {}; \
+ template <class _Tp, class _Up> \
+ struct __is_supported_reduction<std::funname<>, _Tp, _Up> : std::true_type {};
+
+// __is_trivial_plus_operation already exists
+__PSTL_IS_SUPPORTED_REDUCTION(plus)
+__PSTL_IS_SUPPORTED_REDUCTION(minus)
+__PSTL_IS_SUPPORTED_REDUCTION(multiplies)
+__PSTL_IS_SUPPORTED_REDUCTION(logical_and)
+__PSTL_IS_SUPPORTED_REDUCTION(logical_or)
+__PSTL_IS_SUPPORTED_REDUCTION(bit_and)
+__PSTL_IS_SUPPORTED_REDUCTION(bit_or)
+__PSTL_IS_SUPPORTED_REDUCTION(bit_xor)
+
_LIBCPP_BEGIN_NAMESPACE_STD
//===----------------------------------------------------------------------===//
@@ -50,49 +71,16 @@ _LIBCPP_HIDE_FROM_ABI _Tp __pstl_transform_reduce(
_BinaryOperation2 __transform) {
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__has_random_access_iterator_category_or_concept<_ForwardIterator1>::value &&
- __has_random_access_iterator_category_or_concept<_ForwardIterator2>::value) {
+ __has_random_access_iterator_category_or_concept<_ForwardIterator2>::value &&
+ __libcpp_is_contiguous_iterator<_ForwardIterator1>::value &&
+ __libcpp_is_contiguous_iterator<_ForwardIterator2>::value && is_arithmetic_v<_Tp> &&
+ (__is_trivial_plus_operation<_BinaryOperation1, _Tp, _Tp>::value ||
+ __is_supported_reduction<_BinaryOperation1, _Tp, _Tp>::value)) {
return std::__par_backend::__parallel_for_simd_reduction_2(
- std::move(__first1),
- std::move(__first2),
- __last1 - __first1,
- std::move(__init),
- std::move(__reduce),
- [=](__iter_reference<_ForwardIterator1> __in_value_1, __iter_reference<_ForwardIterator1> __in_value_2) {
- return __transform(__in_value_1, __in_value_2);
- });
- } else if constexpr (__is_parallel_execution_policy_v<_ExecutionPolicy> &&
- __has_random_access_iterator_category_or_concept<_ForwardIterator1>::value &&
- __has_random_access_iterator_category_or_concept<_ForwardIterator2>::value) {
- return std::__terminate_on_exception([&] {
- return __par_backend::__parallel_transform_reduce(
- __first1,
- std::move(__last1),
- [__first1, __first2, __transform](_ForwardIterator1 __iter) {
- return __transform(*__iter, *(__first2 + (__iter - __first1)));
- },
- std::move(__init),
- std::move(__reduce),
- [__first1, __first2, __reduce, __transform](
- _ForwardIterator1 __brick_first, _ForwardIterator1 __brick_last, _Tp __brick_init) {
- return std::__pstl_transform_reduce<__remove_parallel_policy_t<_ExecutionPolicy>>(
- __cpu_backend_tag{},
- __brick_first,
- std::move(__brick_last),
- __first2 + (__brick_first - __first1),
- std::move(__brick_init),
- std::move(__reduce),
- std::move(__transform));
- });
- });
- } else {
- return std::transform_reduce(
- std::move(__first1),
- std::move(__last1),
- std::move(__first2),
- std::move(__init),
- std::move(__reduce),
- std::move(__transform));
+ __first1, __first2, __last1 - __first1, __init, __reduce, __transform);
}
+ return std::__pstl_transform_reduce<_ExecutionPolicy>(
+ __cpu_backend_tag{}, __first1, __last1, __first2, std::move(__init), __reduce, __transform);
}
//===----------------------------------------------------------------------===//
@@ -108,36 +96,15 @@ _LIBCPP_HIDE_FROM_ABI _Tp __pstl_transform_reduce(
_BinaryOperation __reduce,
_UnaryOperation __transform) {
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
- __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
+ __has_random_access_iterator_category_or_concept<_ForwardIterator>::value &&
+ __libcpp_is_contiguous_iterator<_ForwardIterator>::value && is_arithmetic_v<_Tp> &&
+ (__is_trivial_plus_operation<_BinaryOperation, _Tp, _Tp>::value ||
+ __is_supported_reduction<_BinaryOperation, _Tp, _Tp>::value)) {
return std::__par_backend::__parallel_for_simd_reduction_1(
- std::move(__first),
- __last - __first,
- std::move(__init),
- std::move(__reduce),
- [=](__iter_reference<_ForwardIterator> __in_value) { return __transform(__in_value); });
- } else if constexpr (__is_parallel_execution_policy_v<_ExecutionPolicy> &&
- __has_random_access_iterator_category_or_concept<_ForwardIterator>::value) {
- return std::__terminate_on_exception([&] {
- return __par_backend::__parallel_transform_reduce(
- std::move(__first),
- std::move(__last),
- [__transform](_ForwardIterator __iter) { return __transform(*__iter); },
- std::move(__init),
- __reduce,
- [__transform, __reduce](auto __brick_first, auto __brick_last, _Tp __brick_init) {
- return std::__pstl_transform_reduce<__remove_parallel_policy_t<_ExecutionPolicy>>(
- __cpu_backend_tag{},
- std::move(__brick_first),
- std::move(__brick_last),
- std::move(__brick_init),
- std::move(__reduce),
- std::move(__transform));
- });
- });
- } else {
- return std::transform_reduce(
- std::move(__first), std::move(__last), std::move(__init), std::move(__reduce), std::move(__transform));
+ __first, __last - __first, __init, __reduce, __transform);
}
+ return std::__pstl_transform_reduce<_ExecutionPolicy>(
+ __cpu_backend_tag{}, __first, __last, std::move(__init), __reduce, __transform);
}
_LIBCPP_END_NAMESPACE_STD
>From 94474817194a47d06a11567dd0e9aeabc7b6da63 Mon Sep 17 00:00:00 2001
From: AntonRydahl <rydahl2610 at gmail.com>
Date: Tue, 26 Sep 2023 20:15:33 -0700
Subject: [PATCH 08/26] Missing return statements in fill and for_each
---
libcxx/include/__algorithm/pstl_backends/gpu_backends/fill.h | 2 +-
.../include/__algorithm/pstl_backends/gpu_backends/for_each.h | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/fill.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/fill.h
index 8dc6bc6a6179c0e..d109495009df895 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/fill.h
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/fill.h
@@ -36,7 +36,7 @@ __pstl_fill(__gpu_backend_tag, _ForwardIterator __first, _ForwardIterator __last
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__has_random_access_iterator_category_or_concept<_ForwardIterator>::value &&
__libcpp_is_contiguous_iterator<_ForwardIterator>::value) {
- std::__par_backend::__parallel_for_simd_val_1(__first, __last - __first, __value);
+ return std::__par_backend::__parallel_for_simd_val_1(__first, __last - __first, __value);
}
// Otherwise, we execute for_each on the CPU instead
return std::__pstl_fill<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __value);
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/for_each.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/for_each.h
index 23c8da27e64ae3b..bab0c87de8f2fc7 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/for_each.h
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/for_each.h
@@ -35,7 +35,7 @@ __pstl_for_each(__gpu_backend_tag, _ForwardIterator __first, _ForwardIterator __
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__has_random_access_iterator_category_or_concept<_ForwardIterator>::value &&
__libcpp_is_contiguous_iterator<_ForwardIterator>::value) {
- std::__par_backend::__parallel_for_simd_1(__first, __last - __first, __func);
+ return std::__par_backend::__parallel_for_simd_1(__first, __last - __first, __func);
}
// Else if the excution policy is parallel, we execute for_each on the CPU instead
return std::__pstl_for_each<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __func);
>From 96adadf8f7227f6543537056f27f98cb18bbe8ce Mon Sep 17 00:00:00 2001
From: AntonRydahl <rydahl2610 at gmail.com>
Date: Wed, 27 Sep 2023 10:31:16 -0700
Subject: [PATCH 09/26] Passing all LIT tests
---
.../__algorithm/pstl_backends/gpu_backends/fill.h | 10 ++++++----
.../pstl_backends/gpu_backends/for_each.h | 8 +++++---
.../pstl_backends/gpu_backends/stable_sort.h | 2 +-
.../pstl_backends/gpu_backends/transform.h | 15 ++++++++-------
.../pstl_backends/gpu_backends/transform_reduce.h | 6 +++---
5 files changed, 23 insertions(+), 18 deletions(-)
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/fill.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/fill.h
index d109495009df895..f32ee8b016b3eae 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/fill.h
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/fill.h
@@ -30,16 +30,18 @@ _LIBCPP_BEGIN_NAMESPACE_STD
template <class _ExecutionPolicy, class _ForwardIterator, class _Tp>
_LIBCPP_HIDE_FROM_ABI void
__pstl_fill(__gpu_backend_tag, _ForwardIterator __first, _ForwardIterator __last, const _Tp& __value) {
- // It is only safe to execute for_each on the GPU, it the execution policy is
+ // It is only safe to execute fill on the GPU, it the execution policy is
// parallel unsequenced, as it is the only execution policy prohibiting throwing
// exceptions and allowing SIMD instructions
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__has_random_access_iterator_category_or_concept<_ForwardIterator>::value &&
__libcpp_is_contiguous_iterator<_ForwardIterator>::value) {
- return std::__par_backend::__parallel_for_simd_val_1(__first, __last - __first, __value);
+ std::__par_backend::__parallel_for_simd_val_1(__first, __last - __first, __value);
+ }
+ // Otherwise, we execute fill on the CPU instead
+ else {
+ std::__pstl_fill<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __value);
}
- // Otherwise, we execute for_each on the CPU instead
- return std::__pstl_fill<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __value);
}
_LIBCPP_END_NAMESPACE_STD
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/for_each.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/for_each.h
index bab0c87de8f2fc7..f96b30b5ba25b24 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/for_each.h
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/for_each.h
@@ -35,10 +35,12 @@ __pstl_for_each(__gpu_backend_tag, _ForwardIterator __first, _ForwardIterator __
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__has_random_access_iterator_category_or_concept<_ForwardIterator>::value &&
__libcpp_is_contiguous_iterator<_ForwardIterator>::value) {
- return std::__par_backend::__parallel_for_simd_1(__first, __last - __first, __func);
+ std::__par_backend::__parallel_for_simd_1(__first, __last - __first, __func);
+ }
+ // Else we fall back to the GPU backend
+ else {
+ std::__pstl_for_each<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __func);
}
- // Else if the excution policy is parallel, we execute for_each on the CPU instead
- return std::__pstl_for_each<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __func);
}
_LIBCPP_END_NAMESPACE_STD
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/stable_sort.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/stable_sort.h
index 1760a9fd9fc9d32..5cd7081ef73e9c1 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/stable_sort.h
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/stable_sort.h
@@ -28,7 +28,7 @@ template <class _ExecutionPolicy, class _RandomAccessIterator, class _Comp>
_LIBCPP_HIDE_FROM_ABI void
__pstl_stable_sort(__gpu_backend_tag, _RandomAccessIterator __first, _RandomAccessIterator __last, _Comp __comp) {
// TODO: Implement GPU backend.
- return __pstl_stable_sort<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __comp);
+ __pstl_stable_sort<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __comp);
}
_LIBCPP_END_NAMESPACE_STD
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform.h
index 10f6e5ff174d675..c2e43cb6d643375 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform.h
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform.h
@@ -38,11 +38,12 @@ _LIBCPP_HIDE_FROM_ABI _ForwardOutIterator __pstl_transform(
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__has_random_access_iterator_category_or_concept<_ForwardIterator>::value &&
__has_random_access_iterator_category_or_concept<_ForwardOutIterator>::value &&
- __libcpp_is_contiguous_iterator<_ForwardIterator>::value) {
- // While the CPU backend captures by reference, [&], that is not valid when
- // offloading to the GPU. Therefore we must capture by value, [=].
- return std::__par_backend::__parallel_for_simd_2(__first, __last - __first, __result, __op);
+ __libcpp_is_contiguous_iterator<_ForwardIterator>::value &&
+ __libcpp_is_contiguous_iterator<_ForwardOutIterator>::value) {
+ std::__par_backend::__parallel_for_simd_2(__first, __last - __first, __result, __op);
+ return __result + (__last - __first);
}
+ // If it is not safe to offload to the GPU, we rely on the CPU backend.
return std::__pstl_transform<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __result, __op);
}
@@ -66,10 +67,10 @@ _LIBCPP_HIDE_FROM_ABI _ForwardOutIterator __pstl_transform(
__libcpp_is_contiguous_iterator<_ForwardIterator1>::value &&
__libcpp_is_contiguous_iterator<_ForwardIterator2>::value &&
__libcpp_is_contiguous_iterator<_ForwardOutIterator>::value) {
- // While the CPU backend captures by reference, [&], that is not valid when
- // offloading to the GPU. Therefore we must capture by value, [=].
- return std::__par_backend::__parallel_for_simd_3(__first1, __last1 - __first1, __first2, __result, __op);
+ std::__par_backend::__parallel_for_simd_3(__first1, __last1 - __first1, __first2, __result, __op);
+ return __result + (__last1 - __first1);
}
+ // If it is not safe to offload to the GPU, we rely on the CPU backend.
return std::__pstl_transform<_ExecutionPolicy>(__cpu_backend_tag{}, __first1, __last1, __first2, __result, __op);
}
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform_reduce.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform_reduce.h
index 8590dd3d024ea69..332bb8abc1b8e0b 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform_reduce.h
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform_reduce.h
@@ -31,13 +31,13 @@
#if !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
template <class _T1, class _T2, class _T3>
-struct __is_supported_reduction : std::false_type {};
+_LIBCPP_HIDE_FROM_ABI struct __is_supported_reduction : std::false_type {};
# define __PSTL_IS_SUPPORTED_REDUCTION(funname) \
template <class _Tp> \
- struct __is_supported_reduction<std::funname<_Tp>, _Tp, _Tp> : std::true_type {}; \
+ _LIBCPP_HIDE_FROM_ABI struct __is_supported_reduction<std::funname<_Tp>, _Tp, _Tp> : std::true_type {}; \
template <class _Tp, class _Up> \
- struct __is_supported_reduction<std::funname<>, _Tp, _Up> : std::true_type {};
+ _LIBCPP_HIDE_FROM_ABI struct __is_supported_reduction<std::funname<>, _Tp, _Up> : std::true_type {};
// __is_trivial_plus_operation already exists
__PSTL_IS_SUPPORTED_REDUCTION(plus)
>From ec5c6cb23d06996b23928bd924a736f8b332c838 Mon Sep 17 00:00:00 2001
From: AntonRydahl <rydahl2610 at gmail.com>
Date: Tue, 3 Oct 2023 20:58:11 -0700
Subject: [PATCH 10/26] Handling value iterators in PSTL GPU backend for C++ 20
---
.../pstl_backends/gpu_backends/omp_offload.h | 219 ++++++++++--------
.../pstl_backends/gpu_backends/transform.h | 6 +
.../gpu_backends/transform_reduce.h | 24 +-
3 files changed, 138 insertions(+), 111 deletions(-)
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/omp_offload.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/omp_offload.h
index 36acafd448ec003..81ec1bbc63d0083 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/omp_offload.h
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/omp_offload.h
@@ -12,6 +12,7 @@
#include <__assert>
#include <__config>
#include <__functional/operations.h>
+#include <__iterator/iterator_traits.h>
#include <__iterator/wrap_iter.h>
#include <__memory/addressof.h>
#include <__memory/pointer_traits.h>
@@ -38,36 +39,66 @@ _LIBCPP_BEGIN_NAMESPACE_STD
namespace __par_backend {
inline namespace __omp_gpu_backend {
-// Checking if a pointer is in a range
-template <typename T1, typename T2, typename T3>
-_LIBCPP_HIDE_FROM_ABI inline bool __omp_in_ptr_range(T1, T2, T3) {
- return false;
+// Functions for eaxtracting the pase pointers
+
+// In the general case we do not need to extract it. This is for instance the
+// case for pointers.
+template <typename _Tp>
+_LIBCPP_HIDE_FROM_ABI inline auto __omp_extract_base_ptr(_Tp p) noexcept {
+ return p;
}
+// For vectors and arrays, etc, we need to extract the underlying base pointer.
template <typename _Tp>
-_LIBCPP_HIDE_FROM_ABI inline bool __omp_in_ptr_range(_Tp* a, _Tp* p, _Tp* b) {
- return std::less_equal<_Tp*>{}(a, p) && std::less<_Tp*>{}(p, b);
+_LIBCPP_HIDE_FROM_ABI inline _Tp __omp_extract_base_ptr(std::__wrap_iter<_Tp> w) noexcept {
+ std::pointer_traits<std::__wrap_iter<_Tp>> PT;
+ return PT.to_address(w);
}
-// In OpenMP, we need to extract the pointer for the underlying data for data
-// structures like std::vector and std::array to be able to map the data to the
-// device.
+//===----------------------------------------------------------------------===//
+// The following four functions differentiates between contiguous iterators and
+// non-contiguous iterators. That allows to use the same implementations for
+// reference and value iterators
+//===----------------------------------------------------------------------===//
-template <typename _Tp, std::enable_if<std::is_pointer<_Tp>::value >::type* = 0>
-_LIBCPP_HIDE_FROM_ABI inline _Tp __omp_extract_base_ptr(_Tp p) {
- return p;
+template <class _Iterator, class _DifferenceType>
+_LIBCPP_HIDE_FROM_ABI void
+__omp_map_to([[maybe_unused]] const _Iterator p, [[maybe_unused]] const _DifferenceType len) noexcept {
+ if constexpr (__libcpp_is_contiguous_iterator<_Iterator>::value) {
+# pragma omp target enter data map(to : p[0 : len])
+ } else {
+# pragma omp target enter data map(to : p)
+ }
}
-template <typename _Tp>
-_LIBCPP_HIDE_FROM_ABI inline auto __omp_extract_base_ptr(_Tp p) {
- return std::addressof(*p);
- ;
+template <class _Iterator, class _DifferenceType>
+_LIBCPP_HIDE_FROM_ABI void
+__omp_map_from([[maybe_unused]] const _Iterator p, [[maybe_unused]] const _DifferenceType len) noexcept {
+ if constexpr (__libcpp_is_contiguous_iterator<_Iterator>::value) {
+# pragma omp target exit data map(from : p[0 : len])
+ } else {
+# pragma omp target exit data map(release : p)
+ }
}
-template <typename _Tp>
-_LIBCPP_HIDE_FROM_ABI inline _Tp __omp_extract_base_ptr(std::__wrap_iter<_Tp> w) {
- std::pointer_traits<std::__wrap_iter<_Tp>> PT;
- return PT.to_address(w);
+template <class _Iterator, class _DifferenceType>
+_LIBCPP_HIDE_FROM_ABI void
+__omp_map_alloc([[maybe_unused]] const _Iterator p, [[maybe_unused]] const _DifferenceType len) noexcept {
+ if constexpr (__libcpp_is_contiguous_iterator<_Iterator>::value) {
+# pragma omp target enter data map(alloc : p[0 : len])
+ } else {
+# pragma omp target enter data map(to : p)
+ }
+}
+
+template <class _Iterator, class _DifferenceType>
+_LIBCPP_HIDE_FROM_ABI void
+__omp_map_free([[maybe_unused]] const _Iterator p, [[maybe_unused]] const _DifferenceType len) noexcept {
+ if constexpr (__libcpp_is_contiguous_iterator<_Iterator>::value) {
+# pragma omp target exit data map(release : p[0 : len])
+ } else {
+# pragma omp target exit data map(release : p)
+ }
}
//===----------------------------------------------------------------------===//
@@ -79,9 +110,11 @@ _LIBCPP_HIDE_FROM_ABI inline _Tp __omp_extract_base_ptr(std::__wrap_iter<_Tp> w)
template <class _Iterator, class _DifferenceType, class _Function>
_LIBCPP_HIDE_FROM_ABI _Iterator __omp_parallel_for_simd_1(
_Iterator __first, _DifferenceType __n, _Function __f, [[maybe_unused]] const int __device = 0) noexcept {
-# pragma omp target teams distribute parallel for simd map(tofrom : __first[0 : __n]) device(__device)
+ __omp_map_to(__first, __n);
+# pragma omp target teams distribute parallel for simd device(__device)
for (_DifferenceType __i = 0; __i < __n; ++__i)
__f(__first[__i]);
+ __omp_map_from(__first, __n);
return __first + __n;
}
@@ -99,11 +132,11 @@ _LIBCPP_HIDE_FROM_ABI _Iterator __parallel_for_simd_1(_Iterator __first, _Differ
template <class _Index, class _DifferenceType, class _Tp>
_LIBCPP_HIDE_FROM_ABI _Index __omp_parallel_for_simd_val_1(
_Index __first, _DifferenceType __n, const _Tp& __value, [[maybe_unused]] const int __device = 0) noexcept {
-# pragma omp target teams distribute parallel for simd map(from : __first[0 : __n]) map(always, to : __value) \
- device(__device)
+ __omp_map_alloc(__first, __n);
+# pragma omp target teams distribute parallel for simd firstprivate(__value) device(__device)
for (_DifferenceType __i = 0; __i < __n; ++__i)
__first[__i] = __value;
-
+ __omp_map_from(__first, __n);
return __first + __n;
}
@@ -125,20 +158,13 @@ _LIBCPP_HIDE_FROM_ABI _Iterator1 __omp_parallel_for_simd_2(
_Iterator2 __first2,
_Function __f,
[[maybe_unused]] const int __device = 0) noexcept {
- if ((!std::is_same<_Iterator1, _Iterator2>::value) ||
- (std::is_same<_Iterator1, _Iterator2>::value &&
- !__omp_gpu_backend::__omp_in_ptr_range(__first1, __first2, __first1 + __n))) {
-# pragma omp target teams distribute parallel for simd map(to : __first1[0 : __n]) map(from : __first2[0 : __n]) \
- device(__device)
- for (_DifferenceType __i = 0; __i < __n; ++__i)
- __first2[__i] = __f(__first1[__i]);
- return __first1 + __n;
- }
-# pragma omp target teams distribute parallel for simd map(tofrom : __first1[0 : __n], __first2[0 : __n]) \
- device(__device)
+ __omp_map_alloc(__first2, __n);
+ __omp_map_to(__first1, __n);
+# pragma omp target teams distribute parallel for simd device(__device)
for (_DifferenceType __i = 0; __i < __n; ++__i)
- __first2[__i] = __f(__first1[__i]);
-
+ *(__first2 + __i) = __f(*(__first1 + __i));
+ __omp_map_from(__first2, __n);
+ __omp_map_free(__first1, __n);
return __first1 + __n;
}
@@ -167,33 +193,15 @@ _LIBCPP_HIDE_FROM_ABI _Iterator1 __omp_parallel_for_simd_3(
_Iterator3 __first3,
_Function __f,
[[maybe_unused]] const int __device = 0) noexcept {
- // It may be that __first3 is in the interval [__first1+__n) or [__firt2+__n)
- // It is, however, undefined behavior to compare two pointers that do not
- // point to the same object or are not the same type.
- // If we can prove that __first3 is not in any of the ranges [__first1+__n)
- // or [__firt2+__n), it is safe to reduce the amount of data copied to and
- // from the device
- constexpr bool are_not_same_type =
- !std::is_same<_Iterator1, _Iterator2>::value && !std::is_same<_Iterator1, _Iterator3>::value;
- const bool no_overlap_13 =
- std::is_same<_Iterator1, _Iterator3>::value &&
- !__omp_gpu_backend::__omp_in_ptr_range(__first1, __first3, __first1 + __n);
- const bool no_overlap_23 =
- std::is_same<_Iterator2, _Iterator3>::value &&
- !__omp_gpu_backend::__omp_in_ptr_range(__first2, __first3, __first2 + __n);
- if (are_not_same_type || (no_overlap_13 && no_overlap_23)) {
-# pragma omp target teams distribute parallel for simd map(to : __first1[0 : __n], __first2[0 : __n]) \
- map(from : __first3[0 : __n]) device(__device)
- for (_DifferenceType __i = 0; __i < __n; ++__i)
- __first3[__i] = __f(__first1[__i], __first2[__i]);
- return __first1 + __n;
- }
- // In the general case, we have to map all data to and from the device
-# pragma omp target teams distribute parallel for simd map( \
- tofrom : __first1[0 : __n], __first2[0 : __n], __first3[0 : __n]) device(__device)
+ __omp_map_to(__first1, __n);
+ __omp_map_to(__first2, __n);
+ __omp_map_alloc(__first3, __n);
+# pragma omp target teams distribute parallel for simd device(__device)
for (_DifferenceType __i = 0; __i < __n; ++__i)
- __first3[__i] = __f(__first1[__i], __first2[__i]);
-
+ *(__first3 + __i) = __f(*(__first1 + __i), *(__first2 + __i));
+ __omp_map_free(__first1, __n);
+ __omp_map_free(__first2, __n);
+ __omp_map_from(__first3, __n);
return __first1 + __n;
}
@@ -215,47 +223,54 @@ _LIBCPP_HIDE_FROM_ABI _Iterator1 __parallel_for_simd_3(
// Templates for reductions
//===----------------------------------------------------------------------===//
-// General case
-
-# define __PSTL_OMP_SIMD_1_REDUCTION(omp_op, std_op) \
- template <class _Iterator, \
- class _DifferenceType, \
- typename _Tp, \
- typename _BinaryOperationType, \
- typename _UnaryOperation> \
- _LIBCPP_HIDE_FROM_ABI _Tp __omp_parallel_for_simd_reduction_1( \
- _Iterator __first, \
- _DifferenceType __n, \
- _Tp __init, \
- std_op<_BinaryOperationType> __reduce, \
- _UnaryOperation __transform/*, \
- [[maybe_unused]] const int __device = 0*/) noexcept { \
-_PSTL_PRAGMA(omp target teams distribute parallel for simd reduction(omp_op:__init) map(to : __first[0 : __n])) /*device(__device))*/ \
- for (_DifferenceType __i = 0; __i < __n; ++__i) \
- __init = __reduce(__init, __transform(__first[__i])); \
- return __init; \
+// In the two following function templates, we map the pointer to the device in
+// different ways depending on if they are contiguou or not.
+
+# define __PSTL_OMP_SIMD_1_REDUCTION(omp_op, std_op) \
+ template <class _Iterator, \
+ class _DifferenceType, \
+ typename _Tp, \
+ typename _BinaryOperationType, \
+ typename _UnaryOperation> \
+ _LIBCPP_HIDE_FROM_ABI _Tp __omp_parallel_for_simd_reduction_1( \
+ _Iterator __first, \
+ _DifferenceType __n, \
+ _Tp __init, \
+ std_op<_BinaryOperationType> __reduce, \
+ _UnaryOperation __transform, \
+ [[maybe_unused]] const int __device = 0) noexcept { \
+ __omp_map_to(__first, __n); \
+_PSTL_PRAGMA(omp target teams distribute parallel for simd reduction(omp_op:__init) device(__device)) \
+ for (_DifferenceType __i = 0; __i < __n; ++__i) \
+ __init = __reduce(__init, __transform(*(__first + __i))); \
+ __omp_map_free(__first, __n); \
+ return __init; \
}
-# define __PSTL_OMP_SIMD_2_REDUCTION(omp_op, std_op) \
- template <class _Iterator1, \
- class _Iterator2, \
- class _DifferenceType, \
- typename _Tp, \
- typename _BinaryOperationType, \
- typename _UnaryOperation > \
- _LIBCPP_HIDE_FROM_ABI _Tp __omp_parallel_for_simd_reduction_2( \
- _Iterator1 __first1, \
- _Iterator2 __first2, \
- _DifferenceType __n, \
- _Tp __init, \
- std_op<_BinaryOperationType> __reduce, \
- _UnaryOperation __transform/*, \
- [[maybe_unused]] const int __device = 0*/) noexcept { \
-_PSTL_PRAGMA(omp target teams distribute parallel for simd reduction(omp_op:__init) map(to : __first1[0 : __n], __first2[0 : __n]))/* device(__device))*/ \
- for (_DifferenceType __i = 0; __i < __n; ++__i) \
- __init = __reduce(__init, __transform(__first1[__i], __first2[__i])); \
- return __init; \
- }
+# define __PSTL_OMP_SIMD_2_REDUCTION(omp_op, std_op) \
+ template <class _Iterator1, \
+ class _Iterator2, \
+ class _DifferenceType, \
+ typename _Tp, \
+ typename _BinaryOperationType, \
+ typename _UnaryOperation > \
+ _LIBCPP_HIDE_FROM_ABI _Tp __omp_parallel_for_simd_reduction_2( \
+ _Iterator1 __first1, \
+ _Iterator2 __first2, \
+ _DifferenceType __n, \
+ _Tp __init, \
+ std_op<_BinaryOperationType> __reduce, \
+ _UnaryOperation __transform, \
+ [[maybe_unused]] const int __device = 0) noexcept { \
+ __omp_map_to(__first1, __n); \
+ __omp_map_to(__first2, __n); \
+_PSTL_PRAGMA(omp target teams distribute parallel for simd reduction(omp_op:__init) device(__device)) \
+ for (_DifferenceType __i = 0; __i < __n; ++__i) \
+ __init = __reduce(__init, __transform(*(__first1 + __i), *(__first2 + __i))); \
+ __omp_map_free(__first1, __n); \
+ __omp_map_free(__first2, __n); \
+ return __init; \
+ } // namespace __omp_gpu_backend
# define __PSTL_OMP_SIMD_REDUCTION(omp_op, std_op) \
__PSTL_OMP_SIMD_1_REDUCTION(omp_op, std_op) \
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform.h
index c2e43cb6d643375..3af2106eb2bda21 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform.h
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform.h
@@ -35,10 +35,13 @@ _LIBCPP_HIDE_FROM_ABI _ForwardOutIterator __pstl_transform(
_ForwardIterator __last,
_ForwardOutIterator __result,
_UnaryOperation __op) {
+ // The interface for the function switched between C++17 and C++20
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__has_random_access_iterator_category_or_concept<_ForwardIterator>::value &&
__has_random_access_iterator_category_or_concept<_ForwardOutIterator>::value &&
+# if _LIBCPP_STD_VER <= 17
__libcpp_is_contiguous_iterator<_ForwardIterator>::value &&
+# endif
__libcpp_is_contiguous_iterator<_ForwardOutIterator>::value) {
std::__par_backend::__parallel_for_simd_2(__first, __last - __first, __result, __op);
return __result + (__last - __first);
@@ -60,12 +63,15 @@ _LIBCPP_HIDE_FROM_ABI _ForwardOutIterator __pstl_transform(
_ForwardIterator2 __first2,
_ForwardOutIterator __result,
_BinaryOperation __op) {
+ // The interface for the function switched between C++17 and C++20
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__has_random_access_iterator_category_or_concept<_ForwardIterator1>::value &&
__has_random_access_iterator_category_or_concept<_ForwardIterator2>::value &&
__has_random_access_iterator_category_or_concept<_ForwardOutIterator>::value &&
+# if _LIBCPP_STD_VER <= 17
__libcpp_is_contiguous_iterator<_ForwardIterator1>::value &&
__libcpp_is_contiguous_iterator<_ForwardIterator2>::value &&
+# endif
__libcpp_is_contiguous_iterator<_ForwardOutIterator>::value) {
std::__par_backend::__parallel_for_simd_3(__first1, __last1 - __first1, __first2, __result, __op);
return __result + (__last1 - __first1);
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform_reduce.h b/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform_reduce.h
index 332bb8abc1b8e0b..eeffe62c040f083 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform_reduce.h
+++ b/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform_reduce.h
@@ -30,14 +30,16 @@
#if !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
+_LIBCPP_BEGIN_NAMESPACE_STD
+
template <class _T1, class _T2, class _T3>
-_LIBCPP_HIDE_FROM_ABI struct __is_supported_reduction : std::false_type {};
+struct _LIBCPP_HIDE_FROM_ABI __is_supported_reduction : std::false_type {};
# define __PSTL_IS_SUPPORTED_REDUCTION(funname) \
template <class _Tp> \
- _LIBCPP_HIDE_FROM_ABI struct __is_supported_reduction<std::funname<_Tp>, _Tp, _Tp> : std::true_type {}; \
+ struct _LIBCPP_HIDE_FROM_ABI __is_supported_reduction<std::funname<_Tp>, _Tp, _Tp> : std::true_type {}; \
template <class _Tp, class _Up> \
- _LIBCPP_HIDE_FROM_ABI struct __is_supported_reduction<std::funname<>, _Tp, _Up> : std::true_type {};
+ struct _LIBCPP_HIDE_FROM_ABI __is_supported_reduction<std::funname<>, _Tp, _Up> : std::true_type {};
// __is_trivial_plus_operation already exists
__PSTL_IS_SUPPORTED_REDUCTION(plus)
@@ -49,8 +51,6 @@ __PSTL_IS_SUPPORTED_REDUCTION(bit_and)
__PSTL_IS_SUPPORTED_REDUCTION(bit_or)
__PSTL_IS_SUPPORTED_REDUCTION(bit_xor)
-_LIBCPP_BEGIN_NAMESPACE_STD
-
//===----------------------------------------------------------------------===//
// Two input iterators
//===----------------------------------------------------------------------===//
@@ -69,11 +69,14 @@ _LIBCPP_HIDE_FROM_ABI _Tp __pstl_transform_reduce(
_Tp __init,
_BinaryOperation1 __reduce,
_BinaryOperation2 __transform) {
+ // The interface for the function switched between C++17 and C++20
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__has_random_access_iterator_category_or_concept<_ForwardIterator1>::value &&
- __has_random_access_iterator_category_or_concept<_ForwardIterator2>::value &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator2>::value && is_arithmetic_v<_Tp> &&
+# if _LIBCPP_STD_VER <= 17
__libcpp_is_contiguous_iterator<_ForwardIterator1>::value &&
- __libcpp_is_contiguous_iterator<_ForwardIterator2>::value && is_arithmetic_v<_Tp> &&
+ __libcpp_is_contiguous_iterator<_ForwardIterator2>::value &&
+# endif
(__is_trivial_plus_operation<_BinaryOperation1, _Tp, _Tp>::value ||
__is_supported_reduction<_BinaryOperation1, _Tp, _Tp>::value)) {
return std::__par_backend::__parallel_for_simd_reduction_2(
@@ -95,9 +98,12 @@ _LIBCPP_HIDE_FROM_ABI _Tp __pstl_transform_reduce(
_Tp __init,
_BinaryOperation __reduce,
_UnaryOperation __transform) {
+ // The interface for the function switched between C++17 and C++20
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
- __has_random_access_iterator_category_or_concept<_ForwardIterator>::value &&
- __libcpp_is_contiguous_iterator<_ForwardIterator>::value && is_arithmetic_v<_Tp> &&
+ __has_random_access_iterator_category_or_concept<_ForwardIterator>::value && is_arithmetic_v<_Tp> &&
+# if _LIBCPP_STD_VER <= 17
+ __libcpp_is_contiguous_iterator<_ForwardIterator>::value &&
+# endif
(__is_trivial_plus_operation<_BinaryOperation, _Tp, _Tp>::value ||
__is_supported_reduction<_BinaryOperation, _Tp, _Tp>::value)) {
return std::__par_backend::__parallel_for_simd_reduction_1(
>From 7971d8126a40ad74acef3ee91105e7d4d05ac9bf Mon Sep 17 00:00:00 2001
From: AntonRydahl <rydahl2610 at gmail.com>
Date: Fri, 6 Oct 2023 11:42:25 -0700
Subject: [PATCH 11/26] Restructuring pstl_backends/gpu/ to
pstl_backends/openmp
---
libcxx/CMakeLists.txt | 36 ++++++++-----------
libcxx/include/CMakeLists.txt | 22 ++++++------
libcxx/include/__algorithm/pstl_backend.h | 34 +++++++++++++-----
.../__algorithm/pstl_backends/cpu_backend.h | 23 +++++++-----
.../pstl_backends/cpu_backends/backend.h | 2 ++
.../__algorithm/pstl_backends/gpu_backend.h | 27 --------------
.../__algorithm/pstl_backends/openmp.h | 27 ++++++++++++++
.../{gpu_backends => openmp}/any_of.h | 13 ++++---
.../{gpu_backends => openmp}/backend.h | 16 +++------
.../{gpu_backends => openmp}/fill.h | 13 ++++---
.../{gpu_backends => openmp}/find_if.h | 13 ++++---
.../{gpu_backends => openmp}/for_each.h | 19 +++++-----
.../{gpu_backends => openmp}/merge.h | 14 ++++----
.../{gpu_backends => openmp}/omp_offload.h | 6 ++--
.../{gpu_backends => openmp}/stable_sort.h | 13 ++++---
.../{gpu_backends => openmp}/transform.h | 25 ++++++-------
.../transform_reduce.h | 23 +++++-------
libcxx/include/__config_site.in | 3 +-
18 files changed, 161 insertions(+), 168 deletions(-)
delete mode 100644 libcxx/include/__algorithm/pstl_backends/gpu_backend.h
create mode 100644 libcxx/include/__algorithm/pstl_backends/openmp.h
rename libcxx/include/__algorithm/pstl_backends/{gpu_backends => openmp}/any_of.h (70%)
rename libcxx/include/__algorithm/pstl_backends/{gpu_backends => openmp}/backend.h (58%)
rename libcxx/include/__algorithm/pstl_backends/{gpu_backends => openmp}/fill.h (78%)
rename libcxx/include/__algorithm/pstl_backends/{gpu_backends => openmp}/find_if.h (71%)
rename libcxx/include/__algorithm/pstl_backends/{gpu_backends => openmp}/for_each.h (74%)
rename libcxx/include/__algorithm/pstl_backends/{gpu_backends => openmp}/merge.h (73%)
rename libcxx/include/__algorithm/pstl_backends/{gpu_backends => openmp}/omp_offload.h (98%)
rename libcxx/include/__algorithm/pstl_backends/{gpu_backends => openmp}/stable_sort.h (68%)
rename libcxx/include/__algorithm/pstl_backends/{gpu_backends => openmp}/transform.h (76%)
rename libcxx/include/__algorithm/pstl_backends/{gpu_backends => openmp}/transform_reduce.h (85%)
diff --git a/libcxx/CMakeLists.txt b/libcxx/CMakeLists.txt
index 16c3bc0a3976918..1272f13df5293fa 100644
--- a/libcxx/CMakeLists.txt
+++ b/libcxx/CMakeLists.txt
@@ -290,19 +290,14 @@ option(LIBCXX_HAS_WIN32_THREAD_API "Ignore auto-detection and force use of win32
option(LIBCXX_HAS_EXTERNAL_THREAD_API
"Build libc++ with an externalized threading API.
This option may only be set to ON when LIBCXX_ENABLE_THREADS=ON." OFF)
-option(LIBCXX_ENABLE_GPU_OFFLOAD
- "Build libc++ with support for GPU offload" OFF)
-if (LIBCXX_ENABLE_THREADS)
- set(LIBCXX_PSTL_CPU_BACKEND "std_thread" CACHE STRING "Which PSTL CPU backend to use")
-else()
- set(LIBCXX_PSTL_CPU_BACKEND "serial" CACHE STRING "Which PSTL CPU backend to use")
-endif()
-
-if (${LIBCXX_ENABLE_GPU_OFFLOAD})
- set(LIBCXX_PSTL_GPU_BACKEND "omp_offload" CACHE STRING "Which PSTL GPU backend to use")
-else()
- set(LIBCXX_PSTL_GPU_BACKEND "none" CACHE STRING "Which PSTL GPU backend to use")
+set(LIBCXX_PSTL_BACKEND "openmp" CACHE INTERNAL "Which PSTL backend to use")
+if (LIBCXX_PSTL_BACKEND STREQUAL "")
+ if (LIBCXX_ENABLE_THREADS)
+ set(LIBCXX_PSTL_BACKEND "std-thread")
+ else()
+ set(LIBCXX_PSTL_BACKEND "serial")
+ endif()
endif()
# Misc options ----------------------------------------------------------------
@@ -804,20 +799,17 @@ if (LIBCXX_ENABLE_ASSERTIONS)
message(FATAL_ERROR "LIBCXX_ENABLE_ASSERTIONS has been replaced by LIBCXX_HARDENING_MODE=safe")
endif()
-if (LIBCXX_PSTL_CPU_BACKEND STREQUAL "serial")
+if (LIBCXX_PSTL_BACKEND STREQUAL "serial")
config_define(1 _LIBCPP_PSTL_CPU_BACKEND_SERIAL)
-elseif(LIBCXX_PSTL_CPU_BACKEND STREQUAL "std_thread")
+elseif (LIBCXX_PSTL_BACKEND STREQUAL "std-thread")
config_define(1 _LIBCPP_PSTL_CPU_BACKEND_THREAD)
-elseif(LIBCXX_PSTL_CPU_BACKEND STREQUAL "libdispatch")
+elseif (LIBCXX_PSTL_BACKEND STREQUAL "libdispatch")
config_define(1 _LIBCPP_PSTL_CPU_BACKEND_LIBDISPATCH)
+elseif (LIBCXX_PSTL_BACKEND STREQUAL "openmp")
+ config_define(1 _LIBCPP_PSTL_BACKEND_OPENMP)
else()
- message(FATAL_ERROR "LIBCXX_PSTL_CPU_BACKEND is set to ${LIBCXX_PSTL_CPU_BACKEND}, which is not a valid backend.
- Valid backends are: serial, std_thread and libdispatch")
-endif()
-
-config_define_if(LIBCXX_ENABLE_GPU_OFFLOAD _LIBCPP_PSTL_GPU_OFFLOAD)
-if (LIBCXX_PSTL_GPU_BACKEND STREQUAL "omp_offload")
- config_define(1 _LIBCPP_PSTL_GPU_BACKEND_OMP_OFFLOAD)
+ message(FATAL_ERROR "LIBCXX_PSTL_BACKEND is set to ${LIBCXX_PSTL_BACKEND}, which is not a valid backend.
+ Valid backends are: serial, std-thread, libdispatch, and openmp.")
endif()
if (LIBCXX_ABI_DEFINES)
diff --git a/libcxx/include/CMakeLists.txt b/libcxx/include/CMakeLists.txt
index 8dfd4e2f26ecf8f..ab38408c1715627 100644
--- a/libcxx/include/CMakeLists.txt
+++ b/libcxx/include/CMakeLists.txt
@@ -85,17 +85,17 @@ set(files
__algorithm/pstl_backends/cpu_backends/thread.h
__algorithm/pstl_backends/cpu_backends/transform.h
__algorithm/pstl_backends/cpu_backends/transform_reduce.h
- __algorithm/pstl_backends/gpu_backend.h
- __algorithm/pstl_backends/gpu_backends/any_of.h
- __algorithm/pstl_backends/gpu_backends/backend.h
- __algorithm/pstl_backends/gpu_backends/fill.h
- __algorithm/pstl_backends/gpu_backends/find_if.h
- __algorithm/pstl_backends/gpu_backends/for_each.h
- __algorithm/pstl_backends/gpu_backends/merge.h
- __algorithm/pstl_backends/gpu_backends/omp_offload.h
- __algorithm/pstl_backends/gpu_backends/stable_sort.h
- __algorithm/pstl_backends/gpu_backends/transform.h
- __algorithm/pstl_backends/gpu_backends/transform_reduce.h
+ __algorithm/pstl_backends/openmp.h
+ __algorithm/pstl_backends/openmp/any_of.h
+ __algorithm/pstl_backends/openmp/backend.h
+ __algorithm/pstl_backends/openmp/fill.h
+ __algorithm/pstl_backends/openmp/find_if.h
+ __algorithm/pstl_backends/openmp/for_each.h
+ __algorithm/pstl_backends/openmp/merge.h
+ __algorithm/pstl_backends/openmp/omp_offload.h
+ __algorithm/pstl_backends/openmp/stable_sort.h
+ __algorithm/pstl_backends/openmp/transform.h
+ __algorithm/pstl_backends/openmp/transform_reduce.h
__algorithm/pstl_copy.h
__algorithm/pstl_count.h
__algorithm/pstl_fill.h
diff --git a/libcxx/include/__algorithm/pstl_backend.h b/libcxx/include/__algorithm/pstl_backend.h
index ed04b4f0cf2cc64..80c9db58e983458 100644
--- a/libcxx/include/__algorithm/pstl_backend.h
+++ b/libcxx/include/__algorithm/pstl_backend.h
@@ -10,7 +10,7 @@
#define _LIBCPP___ALGORITHM_PSTL_BACKEND_H
#include <__algorithm/pstl_backends/cpu_backend.h>
-#include <__algorithm/pstl_backends/gpu_backend.h>
+#include <__algorithm/pstl_backends/openmp.h>
#include <__config>
#include <execution>
@@ -179,6 +179,9 @@ implemented, all the algorithms will eventually forward to the basis algorithms
template <class _ExecutionPolicy>
struct __select_backend;
+# if defined(_LIBCPP_PSTL_CPU_BACKEND_SERIAL) || defined(_LIBCPP_PSTL_CPU_BACKEND_THREAD) || \
+ defined(_LIBCPP_PSTL_CPU_BACKEND_LIBDISPATCH)
+
template <>
struct __select_backend<std::execution::sequenced_policy> {
using type = __cpu_backend_tag;
@@ -191,25 +194,40 @@ struct __select_backend<std::execution::unsequenced_policy> {
};
# endif
-# if defined(_LIBCPP_PSTL_CPU_BACKEND_SERIAL) || defined(_LIBCPP_PSTL_CPU_BACKEND_THREAD) || \
- defined(_LIBCPP_PSTL_CPU_BACKEND_LIBDISPATCH)
template <>
struct __select_backend<std::execution::parallel_policy> {
using type = __cpu_backend_tag;
};
-# if defined(_LIBCPP_PSTL_GPU_OFFLOAD)
template <>
struct __select_backend<std::execution::parallel_unsequenced_policy> {
- using type = __gpu_backend_tag;
+ using type = __cpu_backend_tag;
};
-# else
+
+# elif defined(_LIBCPP_PSTL_BACKEND_OPENMP)
+
template <>
-struct __select_backend<std::execution::parallel_unsequenced_policy> {
- using type = __cpu_backend_tag;
+struct __select_backend<std::execution::sequenced_policy> {
+ using type = __omp_backend_tag;
+};
+
+# if _LIBCPP_STD_VER >= 20
+template <>
+struct __select_backend<std::execution::unsequenced_policy> {
+ using type = __omp_backend_tag;
};
# endif
+template <>
+struct __select_backend<std::execution::parallel_policy> {
+ using type = __omp_backend_tag;
+};
+
+template <>
+struct __select_backend<std::execution::parallel_unsequenced_policy> {
+ using type = __omp_backend_tag;
+};
+
# else
// ...New vendors can add parallel backends here...
diff --git a/libcxx/include/__algorithm/pstl_backends/cpu_backend.h b/libcxx/include/__algorithm/pstl_backends/cpu_backend.h
index e54f331b9430b68..301ea391b33b73a 100644
--- a/libcxx/include/__algorithm/pstl_backends/cpu_backend.h
+++ b/libcxx/include/__algorithm/pstl_backends/cpu_backend.h
@@ -46,14 +46,19 @@
TODO: Document the parallel backend
*/
-#include <__algorithm/pstl_backends/cpu_backends/any_of.h>
-#include <__algorithm/pstl_backends/cpu_backends/backend.h>
-#include <__algorithm/pstl_backends/cpu_backends/fill.h>
-#include <__algorithm/pstl_backends/cpu_backends/find_if.h>
-#include <__algorithm/pstl_backends/cpu_backends/for_each.h>
-#include <__algorithm/pstl_backends/cpu_backends/merge.h>
-#include <__algorithm/pstl_backends/cpu_backends/stable_sort.h>
-#include <__algorithm/pstl_backends/cpu_backends/transform.h>
-#include <__algorithm/pstl_backends/cpu_backends/transform_reduce.h>
+#if defined(_LIBCPP_PSTL_CPU_BACKEND_SERIAL) || defined(_LIBCPP_PSTL_CPU_BACKEND_THREAD) || \
+ defined(_LIBCPP_PSTL_CPU_BACKEND_LIBDISPATCH)
+
+# include <__algorithm/pstl_backends/cpu_backends/any_of.h>
+# include <__algorithm/pstl_backends/cpu_backends/backend.h>
+# include <__algorithm/pstl_backends/cpu_backends/fill.h>
+# include <__algorithm/pstl_backends/cpu_backends/find_if.h>
+# include <__algorithm/pstl_backends/cpu_backends/for_each.h>
+# include <__algorithm/pstl_backends/cpu_backends/merge.h>
+# include <__algorithm/pstl_backends/cpu_backends/stable_sort.h>
+# include <__algorithm/pstl_backends/cpu_backends/transform.h>
+# include <__algorithm/pstl_backends/cpu_backends/transform_reduce.h>
+
+#endif
#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_CPU_BACKEND_H
diff --git a/libcxx/include/__algorithm/pstl_backends/cpu_backends/backend.h b/libcxx/include/__algorithm/pstl_backends/cpu_backends/backend.h
index ea2210a4a7adbdb..b8e9b1e28201d16 100644
--- a/libcxx/include/__algorithm/pstl_backends/cpu_backends/backend.h
+++ b/libcxx/include/__algorithm/pstl_backends/cpu_backends/backend.h
@@ -18,6 +18,8 @@
# include <__algorithm/pstl_backends/cpu_backends/thread.h>
#elif defined(_LIBCPP_PSTL_CPU_BACKEND_LIBDISPATCH)
# include <__algorithm/pstl_backends/cpu_backends/libdispatch.h>
+#elif defined(_LIBCPP_PSTL_BACKEND_OPENMP)
+// OpenMP covers both CPU and GPU backends
#else
# error "Invalid CPU backend choice"
#endif
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backend.h b/libcxx/include/__algorithm/pstl_backends/gpu_backend.h
deleted file mode 100644
index f41332fbf9f6d42..000000000000000
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backend.h
+++ /dev/null
@@ -1,27 +0,0 @@
-//===----------------------------------------------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_H
-#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_H
-
-#include <__config>
-
-#include <__algorithm/pstl_backends/gpu_backends/backend.h>
-
-#if defined(_LIBCPP_PSTL_GPU_OFFLOAD)
-# include <__algorithm/pstl_backends/gpu_backends/any_of.h>
-# include <__algorithm/pstl_backends/gpu_backends/fill.h>
-# include <__algorithm/pstl_backends/gpu_backends/find_if.h>
-# include <__algorithm/pstl_backends/gpu_backends/for_each.h>
-# include <__algorithm/pstl_backends/gpu_backends/merge.h>
-# include <__algorithm/pstl_backends/gpu_backends/stable_sort.h>
-# include <__algorithm/pstl_backends/gpu_backends/transform.h>
-# include <__algorithm/pstl_backends/gpu_backends/transform_reduce.h>
-#endif
-
-#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_H
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp.h b/libcxx/include/__algorithm/pstl_backends/openmp.h
new file mode 100644
index 000000000000000..7787c82ff98825a
--- /dev/null
+++ b/libcxx/include/__algorithm/pstl_backends/openmp.h
@@ -0,0 +1,27 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_H
+#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_H
+
+#include <__config>
+
+#include <__algorithm/pstl_backends/openmp/backend.h>
+
+#if defined(_LIBCPP_PSTL_BACKEND_OPENMP)
+# include <__algorithm/pstl_backends/openmp/any_of.h>
+# include <__algorithm/pstl_backends/openmp/fill.h>
+# include <__algorithm/pstl_backends/openmp/find_if.h>
+# include <__algorithm/pstl_backends/openmp/for_each.h>
+# include <__algorithm/pstl_backends/openmp/merge.h>
+# include <__algorithm/pstl_backends/openmp/stable_sort.h>
+# include <__algorithm/pstl_backends/openmp/transform.h>
+# include <__algorithm/pstl_backends/openmp/transform_reduce.h>
+#endif
+
+#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_H
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/any_of.h b/libcxx/include/__algorithm/pstl_backends/openmp/any_of.h
similarity index 70%
rename from libcxx/include/__algorithm/pstl_backends/gpu_backends/any_of.h
rename to libcxx/include/__algorithm/pstl_backends/openmp/any_of.h
index 8d911de55dcd685..2b9a88fc58edcdd 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/any_of.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/any_of.h
@@ -6,13 +6,12 @@
//
//===----------------------------------------------------------------------===//
-#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_ANY_OF_H
-#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_ANY_OF_H
+#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_ANY_OF_H
+#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_ANY_OF_H
#include <__algorithm/any_of.h>
#include <__algorithm/find_if.h>
-#include <__algorithm/pstl_backends/cpu_backends/backend.h>
-#include <__algorithm/pstl_backends/gpu_backends/backend.h>
+#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__atomic/atomic.h>
#include <__atomic/memory_order.h>
#include <__config>
@@ -29,13 +28,13 @@ _LIBCPP_BEGIN_NAMESPACE_STD
template <class _ExecutionPolicy, class _ForwardIterator, class _Predicate>
_LIBCPP_HIDE_FROM_ABI bool
-__pstl_any_of(__gpu_backend_tag, _ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) {
+__pstl_any_of(__omp_backend_tag, _ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) {
// TODO: Implement GPU backend
- return std::__pstl_any_of<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __pred);
+ return std::any_of(__first, __last, __pred);
}
_LIBCPP_END_NAMESPACE_STD
#endif // !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
-#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_ANY_OF_H
+#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_ANY_OF_H
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/backend.h b/libcxx/include/__algorithm/pstl_backends/openmp/backend.h
similarity index 58%
rename from libcxx/include/__algorithm/pstl_backends/gpu_backends/backend.h
rename to libcxx/include/__algorithm/pstl_backends/openmp/backend.h
index a03ad35d8d2ae3e..e4e6136082a3427 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/backend.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/backend.h
@@ -6,19 +6,13 @@
//
//===----------------------------------------------------------------------===//
-#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_BACKEND_H
-#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_BACKEND_H
+#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_BACKEND_H
+#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_BACKEND_H
#include <__config>
#include <cstddef>
-#if defined(_LIBCPP_PSTL_GPU_OFFLOAD)
-# if defined(_LIBCPP_PSTL_GPU_BACKEND_OMP_OFFLOAD)
-# include <__algorithm/pstl_backends/gpu_backends/omp_offload.h>
-# else
-# error Invalid PSTL GPU backend
-# endif
-#endif
+#include <__algorithm/pstl_backends/openmp/omp_offload.h>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
@@ -28,10 +22,10 @@
_LIBCPP_BEGIN_NAMESPACE_STD
-struct __gpu_backend_tag {};
+struct __omp_backend_tag {};
_LIBCPP_END_NAMESPACE_STD
#endif // _LIBCPP_STD_VER >= 17
-#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_BACKEND_H
+#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_BACKEND_H
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/fill.h b/libcxx/include/__algorithm/pstl_backends/openmp/fill.h
similarity index 78%
rename from libcxx/include/__algorithm/pstl_backends/gpu_backends/fill.h
rename to libcxx/include/__algorithm/pstl_backends/openmp/fill.h
index f32ee8b016b3eae..56341b04f0e50df 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/fill.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/fill.h
@@ -6,12 +6,11 @@
//
//===----------------------------------------------------------------------===//
-#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKNEDS_FILL_H
-#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKNEDS_FILL_H
+#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_FILL_H
+#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_FILL_H
#include <__algorithm/fill.h>
-#include <__algorithm/pstl_backends/cpu_backends/backend.h>
-#include <__algorithm/pstl_backends/gpu_backends/backend.h>
+#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__config>
#include <__iterator/concepts.h>
#include <__iterator/iterator_traits.h>
@@ -29,7 +28,7 @@ _LIBCPP_BEGIN_NAMESPACE_STD
template <class _ExecutionPolicy, class _ForwardIterator, class _Tp>
_LIBCPP_HIDE_FROM_ABI void
-__pstl_fill(__gpu_backend_tag, _ForwardIterator __first, _ForwardIterator __last, const _Tp& __value) {
+__pstl_fill(__omp_backend_tag, _ForwardIterator __first, _ForwardIterator __last, const _Tp& __value) {
// It is only safe to execute fill on the GPU, it the execution policy is
// parallel unsequenced, as it is the only execution policy prohibiting throwing
// exceptions and allowing SIMD instructions
@@ -40,7 +39,7 @@ __pstl_fill(__gpu_backend_tag, _ForwardIterator __first, _ForwardIterator __last
}
// Otherwise, we execute fill on the CPU instead
else {
- std::__pstl_fill<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __value);
+ std::fill(__first, __last, __value);
}
}
@@ -48,4 +47,4 @@ _LIBCPP_END_NAMESPACE_STD
#endif // !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
-#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKNEDS_FILL_H
+#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_FILL_H
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/find_if.h b/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h
similarity index 71%
rename from libcxx/include/__algorithm/pstl_backends/gpu_backends/find_if.h
rename to libcxx/include/__algorithm/pstl_backends/openmp/find_if.h
index 2d34938f92dff38..1e78cb67cd75978 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/find_if.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h
@@ -6,12 +6,11 @@
//
//===----------------------------------------------------------------------===//
-#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_FIND_IF_H
-#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_FIND_IF_H
+#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_FIND_IF_H
+#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_FIND_IF_H
#include <__algorithm/find_if.h>
-#include <__algorithm/pstl_backends/cpu_backends/backend.h>
-#include <__algorithm/pstl_backends/gpu_backends/backend.h>
+#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__atomic/atomic.h>
#include <__config>
#include <__functional/operations.h>
@@ -32,13 +31,13 @@ _LIBCPP_BEGIN_NAMESPACE_STD
template <class _ExecutionPolicy, class _ForwardIterator, class _Predicate>
_LIBCPP_HIDE_FROM_ABI _ForwardIterator
-__pstl_find_if(__gpu_backend_tag, _ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) {
+__pstl_find_if(__omp_backend_tag, _ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) {
// TODO: Implement the GPU backend
- return std::__pstl_find_if<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __pred);
+ return std::find_if(__first, __last, __pred);
}
_LIBCPP_END_NAMESPACE_STD
#endif // !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
-#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_FIND_IF_H
+#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_FIND_IF_H
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/for_each.h b/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h
similarity index 74%
rename from libcxx/include/__algorithm/pstl_backends/gpu_backends/for_each.h
rename to libcxx/include/__algorithm/pstl_backends/openmp/for_each.h
index f96b30b5ba25b24..401cdfade50a103 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/for_each.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h
@@ -6,12 +6,11 @@
//
//===----------------------------------------------------------------------===//
-#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKNEDS_FOR_EACH_H
-#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKNEDS_FOR_EACH_H
+#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_FOR_EACH_H
+#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_FOR_EACH_H
#include <__algorithm/for_each.h>
-#include <__algorithm/pstl_backends/cpu_backends/backend.h>
-#include <__algorithm/pstl_backends/gpu_backends/backend.h>
+#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__config>
#include <__iterator/concepts.h>
#include <__type_traits/is_execution_policy.h>
@@ -28,7 +27,7 @@ _LIBCPP_BEGIN_NAMESPACE_STD
template <class _ExecutionPolicy, class _ForwardIterator, class _Functor>
_LIBCPP_HIDE_FROM_ABI void
-__pstl_for_each(__gpu_backend_tag, _ForwardIterator __first, _ForwardIterator __last, _Functor __func) {
+__pstl_for_each(__omp_backend_tag, _ForwardIterator __first, _ForwardIterator __last, _Functor __func) {
// It is only safe to execute for_each on the GPU, it the execution policy is
// parallel unsequenced, as it is the only execution policy prohibiting throwing
// exceptions and allowing SIMD instructions
@@ -36,10 +35,10 @@ __pstl_for_each(__gpu_backend_tag, _ForwardIterator __first, _ForwardIterator __
__has_random_access_iterator_category_or_concept<_ForwardIterator>::value &&
__libcpp_is_contiguous_iterator<_ForwardIterator>::value) {
std::__par_backend::__parallel_for_simd_1(__first, __last - __first, __func);
- }
- // Else we fall back to the GPU backend
- else {
- std::__pstl_for_each<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __func);
+ } else {
+ // If it is not safe to offload to the GPU, we call the serial
+ // implementation
+ std::for_each(__first, __last, __func);
}
}
@@ -47,4 +46,4 @@ _LIBCPP_END_NAMESPACE_STD
#endif // !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
-#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKNEDS_FOR_EACH_H
+#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_FOR_EACH_H
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/merge.h b/libcxx/include/__algorithm/pstl_backends/openmp/merge.h
similarity index 73%
rename from libcxx/include/__algorithm/pstl_backends/gpu_backends/merge.h
rename to libcxx/include/__algorithm/pstl_backends/openmp/merge.h
index bc947ebb27ac7f0..23036e1cc853980 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/merge.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/merge.h
@@ -6,12 +6,11 @@
//
//===----------------------------------------------------------------------===//
-#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_MERGE_H
-#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_MERGE_H
+#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_MERGE_H
+#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_MERGE_H
#include <__algorithm/merge.h>
-#include <__algorithm/pstl_backends/cpu_backends/backend.h>
-#include <__algorithm/pstl_backends/gpu_backends/backend.h>
+#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__config>
#include <__iterator/concepts.h>
#include <__type_traits/is_execution_policy.h>
@@ -32,7 +31,7 @@ template <class _ExecutionPolicy,
class _ForwardOutIterator,
class _Comp>
_LIBCPP_HIDE_FROM_ABI _ForwardOutIterator __pstl_merge(
- __gpu_backend_tag,
+ __omp_backend_tag,
_ForwardIterator1 __first1,
_ForwardIterator1 __last1,
_ForwardIterator2 __first2,
@@ -40,12 +39,11 @@ _LIBCPP_HIDE_FROM_ABI _ForwardOutIterator __pstl_merge(
_ForwardOutIterator __result,
_Comp __comp) {
// TODO: Implement GPU backend
- return std::__pstl_merge<_ExecutionPolicy>(
- __cpu_backend_tag{}, __first1, __last1, __first2, __last2, __result, __comp);
+ return std::merge(__first1, __last1, __first2, __last2, __result, __comp);
}
_LIBCPP_END_NAMESPACE_STD
#endif // !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
-#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_MERGE_H
+#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_MERGE_H
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/omp_offload.h b/libcxx/include/__algorithm/pstl_backends/openmp/omp_offload.h
similarity index 98%
rename from libcxx/include/__algorithm/pstl_backends/gpu_backends/omp_offload.h
rename to libcxx/include/__algorithm/pstl_backends/openmp/omp_offload.h
index 81ec1bbc63d0083..ee0bfe13bac9010 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/omp_offload.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/omp_offload.h
@@ -6,8 +6,8 @@
//
//===----------------------------------------------------------------------===//
-#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_CPU_BACKENDS_OMP_OFFLOAD_H
-#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_CPU_BACKENDS_OMP_OFFLOAD_H
+#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_OMP_OFFLOAD_H
+#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_OMP_OFFLOAD_H
#include <__assert>
#include <__config>
@@ -346,4 +346,4 @@ _LIBCPP_END_NAMESPACE_STD
_LIBCPP_POP_MACROS
-#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_CPU_BACKENDS_OMP_OFFLOAD_H
+#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_OMP_OFFLOAD_H
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/stable_sort.h b/libcxx/include/__algorithm/pstl_backends/openmp/stable_sort.h
similarity index 68%
rename from libcxx/include/__algorithm/pstl_backends/gpu_backends/stable_sort.h
rename to libcxx/include/__algorithm/pstl_backends/openmp/stable_sort.h
index 5cd7081ef73e9c1..7d28b8de77983a7 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/stable_sort.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/stable_sort.h
@@ -6,11 +6,10 @@
//
//===----------------------------------------------------------------------===//
-#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_STABLE_SORT_H
-#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_STABLE_SORT_H
+#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_STABLE_SORT_H
+#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_STABLE_SORT_H
-#include <__algorithm/pstl_backends/cpu_backends/backend.h>
-#include <__algorithm/pstl_backends/gpu_backends/backend.h>
+#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__algorithm/stable_sort.h>
#include <__config>
#include <__type_traits/is_execution_policy.h>
@@ -26,13 +25,13 @@ _LIBCPP_BEGIN_NAMESPACE_STD
template <class _ExecutionPolicy, class _RandomAccessIterator, class _Comp>
_LIBCPP_HIDE_FROM_ABI void
-__pstl_stable_sort(__gpu_backend_tag, _RandomAccessIterator __first, _RandomAccessIterator __last, _Comp __comp) {
+__pstl_stable_sort(__omp_backend_tag, _RandomAccessIterator __first, _RandomAccessIterator __last, _Comp __comp) {
// TODO: Implement GPU backend.
- __pstl_stable_sort<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __comp);
+ std::stable_sort(__first, __last, __comp);
}
_LIBCPP_END_NAMESPACE_STD
#endif // !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
-#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_STABLE_SORT_H
+#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_STABLE_SORT_H
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform.h b/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
similarity index 76%
rename from libcxx/include/__algorithm/pstl_backends/gpu_backends/transform.h
rename to libcxx/include/__algorithm/pstl_backends/openmp/transform.h
index 3af2106eb2bda21..6dc7ab22c98cc35 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
@@ -6,11 +6,10 @@
//
//===----------------------------------------------------------------------===//
-#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_TRANSFORM_H
-#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_TRANSFORM_H
+#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_TRANSFORM_H
+#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_TRANSFORM_H
-#include <__algorithm/pstl_backends/cpu_backends/backend.h>
-#include <__algorithm/pstl_backends/gpu_backends/backend.h>
+#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__algorithm/transform.h>
#include <__config>
#include <__iterator/concepts.h>
@@ -30,7 +29,7 @@ _LIBCPP_BEGIN_NAMESPACE_STD
template <class _ExecutionPolicy, class _ForwardIterator, class _ForwardOutIterator, class _UnaryOperation>
_LIBCPP_HIDE_FROM_ABI _ForwardOutIterator __pstl_transform(
- __gpu_backend_tag,
+ __omp_backend_tag,
_ForwardIterator __first,
_ForwardIterator __last,
_ForwardOutIterator __result,
@@ -46,8 +45,8 @@ _LIBCPP_HIDE_FROM_ABI _ForwardOutIterator __pstl_transform(
std::__par_backend::__parallel_for_simd_2(__first, __last - __first, __result, __op);
return __result + (__last - __first);
}
- // If it is not safe to offload to the GPU, we rely on the CPU backend.
- return std::__pstl_transform<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __result, __op);
+ // If it is not safe to offload to the GPU, we rely on the serial backend.
+ return std::transform(__first, __last, __result, __op);
}
template <class _ExecutionPolicy,
@@ -57,7 +56,7 @@ template <class _ExecutionPolicy,
class _BinaryOperation,
enable_if_t<is_execution_policy_v<__remove_cvref_t<_ExecutionPolicy>>, int> = 0>
_LIBCPP_HIDE_FROM_ABI _ForwardOutIterator __pstl_transform(
- __gpu_backend_tag,
+ __omp_backend_tag,
_ForwardIterator1 __first1,
_ForwardIterator1 __last1,
_ForwardIterator2 __first2,
@@ -68,20 +67,16 @@ _LIBCPP_HIDE_FROM_ABI _ForwardOutIterator __pstl_transform(
__has_random_access_iterator_category_or_concept<_ForwardIterator1>::value &&
__has_random_access_iterator_category_or_concept<_ForwardIterator2>::value &&
__has_random_access_iterator_category_or_concept<_ForwardOutIterator>::value &&
-# if _LIBCPP_STD_VER <= 17
- __libcpp_is_contiguous_iterator<_ForwardIterator1>::value &&
- __libcpp_is_contiguous_iterator<_ForwardIterator2>::value &&
-# endif
__libcpp_is_contiguous_iterator<_ForwardOutIterator>::value) {
std::__par_backend::__parallel_for_simd_3(__first1, __last1 - __first1, __first2, __result, __op);
return __result + (__last1 - __first1);
}
- // If it is not safe to offload to the GPU, we rely on the CPU backend.
- return std::__pstl_transform<_ExecutionPolicy>(__cpu_backend_tag{}, __first1, __last1, __first2, __result, __op);
+ // If it is not safe to offload to the GPU, we call the serial implementation
+ return std::transform(__first1, __last1, __first2, __result, __op);
}
_LIBCPP_END_NAMESPACE_STD
#endif // !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
-#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_TRANSFORM_H
+#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_TRANSFORM_H
diff --git a/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform_reduce.h b/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h
similarity index 85%
rename from libcxx/include/__algorithm/pstl_backends/gpu_backends/transform_reduce.h
rename to libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h
index eeffe62c040f083..c63e456b314c1c8 100644
--- a/libcxx/include/__algorithm/pstl_backends/gpu_backends/transform_reduce.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h
@@ -6,11 +6,10 @@
//
//===----------------------------------------------------------------------===//
-#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_TRANSFORM_REDUCE_H
-#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_TRANSFORM_REDUCE_H
+#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_TRANSFORM_REDUCE_H
+#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_TRANSFORM_REDUCE_H
-#include <__algorithm/pstl_backends/cpu_backends/backend.h>
-#include <__algorithm/pstl_backends/gpu_backends/backend.h>
+#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__config>
#include <__functional/operations.h>
#include <__iterator/concepts.h>
@@ -62,7 +61,7 @@ template <class _ExecutionPolicy,
class _BinaryOperation1,
class _BinaryOperation2>
_LIBCPP_HIDE_FROM_ABI _Tp __pstl_transform_reduce(
- __gpu_backend_tag,
+ __omp_backend_tag,
_ForwardIterator1 __first1,
_ForwardIterator1 __last1,
_ForwardIterator2 __first2,
@@ -82,8 +81,7 @@ _LIBCPP_HIDE_FROM_ABI _Tp __pstl_transform_reduce(
return std::__par_backend::__parallel_for_simd_reduction_2(
__first1, __first2, __last1 - __first1, __init, __reduce, __transform);
}
- return std::__pstl_transform_reduce<_ExecutionPolicy>(
- __cpu_backend_tag{}, __first1, __last1, __first2, std::move(__init), __reduce, __transform);
+ return std::transform_reduce(__first1, __last1, __first2, std::move(__init), __reduce, __transform);
}
//===----------------------------------------------------------------------===//
@@ -92,7 +90,7 @@ _LIBCPP_HIDE_FROM_ABI _Tp __pstl_transform_reduce(
template <class _ExecutionPolicy, class _ForwardIterator, class _Tp, class _BinaryOperation, class _UnaryOperation>
_LIBCPP_HIDE_FROM_ABI _Tp __pstl_transform_reduce(
- __gpu_backend_tag,
+ __omp_backend_tag,
_ForwardIterator __first,
_ForwardIterator __last,
_Tp __init,
@@ -101,20 +99,17 @@ _LIBCPP_HIDE_FROM_ABI _Tp __pstl_transform_reduce(
// The interface for the function switched between C++17 and C++20
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__has_random_access_iterator_category_or_concept<_ForwardIterator>::value && is_arithmetic_v<_Tp> &&
-# if _LIBCPP_STD_VER <= 17
- __libcpp_is_contiguous_iterator<_ForwardIterator>::value &&
-# endif
(__is_trivial_plus_operation<_BinaryOperation, _Tp, _Tp>::value ||
__is_supported_reduction<_BinaryOperation, _Tp, _Tp>::value)) {
return std::__par_backend::__parallel_for_simd_reduction_1(
__first, __last - __first, __init, __reduce, __transform);
}
- return std::__pstl_transform_reduce<_ExecutionPolicy>(
- __cpu_backend_tag{}, __first, __last, std::move(__init), __reduce, __transform);
+ // If it is not safe to offload to the GPU, we call the serial implementation
+ return std::transform_reduce(__first, __last, std::move(__init), __reduce, __transform);
}
_LIBCPP_END_NAMESPACE_STD
#endif // !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
-#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKENDS_TRANSFORM_REDUCE_H
+#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_TRANSFORM_REDUCE_H
diff --git a/libcxx/include/__config_site.in b/libcxx/include/__config_site.in
index e7fb4f423079333..21334e797b89632 100644
--- a/libcxx/include/__config_site.in
+++ b/libcxx/include/__config_site.in
@@ -34,8 +34,7 @@
#cmakedefine _LIBCPP_PSTL_CPU_BACKEND_SERIAL
#cmakedefine _LIBCPP_PSTL_CPU_BACKEND_THREAD
#cmakedefine _LIBCPP_PSTL_CPU_BACKEND_LIBDISPATCH
-#cmakedefine _LIBCPP_PSTL_GPU_BACKEND_OMP_OFFLOAD
-#cmakedefine _LIBCPP_PSTL_GPU_OFFLOAD
+#cmakedefine _LIBCPP_PSTL_BACKEND_OPENMP
// Hardening.
#cmakedefine01 _LIBCPP_ENABLE_HARDENED_MODE_DEFAULT
>From a3aaf5abaa2eedb081d194245c15d3e6f1bf5b05 Mon Sep 17 00:00:00 2001
From: AntonRydahl <rydahl2610 at gmail.com>
Date: Fri, 6 Oct 2023 12:39:29 -0700
Subject: [PATCH 12/26] Configured PSTL OpenMP backend to use the serial CPU
backend when it is not safe to offload
---
libcxx/include/__algorithm/pstl_backend.h | 18 +++---------------
.../__algorithm/pstl_backends/cpu_backend.h | 5 -----
.../pstl_backends/cpu_backends/backend.h | 4 +---
.../include/__algorithm/pstl_backends/openmp.h | 6 ++----
.../__algorithm/pstl_backends/openmp/any_of.h | 3 ++-
.../__algorithm/pstl_backends/openmp/fill.h | 3 ++-
.../__algorithm/pstl_backends/openmp/find_if.h | 3 ++-
.../pstl_backends/openmp/for_each.h | 9 +++++----
.../__algorithm/pstl_backends/openmp/merge.h | 4 +++-
.../pstl_backends/openmp/stable_sort.h | 3 ++-
.../pstl_backends/openmp/transform.h | 12 +++++-------
.../pstl_backends/openmp/transform_reduce.h | 12 +++++-------
12 files changed, 32 insertions(+), 50 deletions(-)
diff --git a/libcxx/include/__algorithm/pstl_backend.h b/libcxx/include/__algorithm/pstl_backend.h
index 80c9db58e983458..dbd6f4dae8cbefe 100644
--- a/libcxx/include/__algorithm/pstl_backend.h
+++ b/libcxx/include/__algorithm/pstl_backend.h
@@ -179,9 +179,6 @@ implemented, all the algorithms will eventually forward to the basis algorithms
template <class _ExecutionPolicy>
struct __select_backend;
-# if defined(_LIBCPP_PSTL_CPU_BACKEND_SERIAL) || defined(_LIBCPP_PSTL_CPU_BACKEND_THREAD) || \
- defined(_LIBCPP_PSTL_CPU_BACKEND_LIBDISPATCH)
-
template <>
struct __select_backend<std::execution::sequenced_policy> {
using type = __cpu_backend_tag;
@@ -194,6 +191,9 @@ struct __select_backend<std::execution::unsequenced_policy> {
};
# endif
+# if defined(_LIBCPP_PSTL_CPU_BACKEND_SERIAL) || defined(_LIBCPP_PSTL_CPU_BACKEND_THREAD) || \
+ defined(_LIBCPP_PSTL_CPU_BACKEND_LIBDISPATCH)
+
template <>
struct __select_backend<std::execution::parallel_policy> {
using type = __cpu_backend_tag;
@@ -206,18 +206,6 @@ struct __select_backend<std::execution::parallel_unsequenced_policy> {
# elif defined(_LIBCPP_PSTL_BACKEND_OPENMP)
-template <>
-struct __select_backend<std::execution::sequenced_policy> {
- using type = __omp_backend_tag;
-};
-
-# if _LIBCPP_STD_VER >= 20
-template <>
-struct __select_backend<std::execution::unsequenced_policy> {
- using type = __omp_backend_tag;
-};
-# endif
-
template <>
struct __select_backend<std::execution::parallel_policy> {
using type = __omp_backend_tag;
diff --git a/libcxx/include/__algorithm/pstl_backends/cpu_backend.h b/libcxx/include/__algorithm/pstl_backends/cpu_backend.h
index 301ea391b33b73a..50876ed2532eb41 100644
--- a/libcxx/include/__algorithm/pstl_backends/cpu_backend.h
+++ b/libcxx/include/__algorithm/pstl_backends/cpu_backend.h
@@ -46,9 +46,6 @@
TODO: Document the parallel backend
*/
-#if defined(_LIBCPP_PSTL_CPU_BACKEND_SERIAL) || defined(_LIBCPP_PSTL_CPU_BACKEND_THREAD) || \
- defined(_LIBCPP_PSTL_CPU_BACKEND_LIBDISPATCH)
-
# include <__algorithm/pstl_backends/cpu_backends/any_of.h>
# include <__algorithm/pstl_backends/cpu_backends/backend.h>
# include <__algorithm/pstl_backends/cpu_backends/fill.h>
@@ -59,6 +56,4 @@
# include <__algorithm/pstl_backends/cpu_backends/transform.h>
# include <__algorithm/pstl_backends/cpu_backends/transform_reduce.h>
-#endif
-
#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_CPU_BACKEND_H
diff --git a/libcxx/include/__algorithm/pstl_backends/cpu_backends/backend.h b/libcxx/include/__algorithm/pstl_backends/cpu_backends/backend.h
index b8e9b1e28201d16..51aa878d734514d 100644
--- a/libcxx/include/__algorithm/pstl_backends/cpu_backends/backend.h
+++ b/libcxx/include/__algorithm/pstl_backends/cpu_backends/backend.h
@@ -12,14 +12,12 @@
#include <__config>
#include <cstddef>
-#if defined(_LIBCPP_PSTL_CPU_BACKEND_SERIAL)
+#if defined(_LIBCPP_PSTL_CPU_BACKEND_SERIAL) || defined(_LIBCPP_PSTL_BACKEND_OPENMP)
# include <__algorithm/pstl_backends/cpu_backends/serial.h>
#elif defined(_LIBCPP_PSTL_CPU_BACKEND_THREAD)
# include <__algorithm/pstl_backends/cpu_backends/thread.h>
#elif defined(_LIBCPP_PSTL_CPU_BACKEND_LIBDISPATCH)
# include <__algorithm/pstl_backends/cpu_backends/libdispatch.h>
-#elif defined(_LIBCPP_PSTL_BACKEND_OPENMP)
-// OpenMP covers both CPU and GPU backends
#else
# error "Invalid CPU backend choice"
#endif
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp.h b/libcxx/include/__algorithm/pstl_backends/openmp.h
index 7787c82ff98825a..4c121e187ae246c 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp.h
@@ -9,11 +9,10 @@
#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_H
#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_H
-#include <__config>
+# include <__config>
-#include <__algorithm/pstl_backends/openmp/backend.h>
+# include <__algorithm/pstl_backends/openmp/backend.h>
-#if defined(_LIBCPP_PSTL_BACKEND_OPENMP)
# include <__algorithm/pstl_backends/openmp/any_of.h>
# include <__algorithm/pstl_backends/openmp/fill.h>
# include <__algorithm/pstl_backends/openmp/find_if.h>
@@ -22,6 +21,5 @@
# include <__algorithm/pstl_backends/openmp/stable_sort.h>
# include <__algorithm/pstl_backends/openmp/transform.h>
# include <__algorithm/pstl_backends/openmp/transform_reduce.h>
-#endif
#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_H
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/any_of.h b/libcxx/include/__algorithm/pstl_backends/openmp/any_of.h
index 2b9a88fc58edcdd..a36f545d5bd719b 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/any_of.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/any_of.h
@@ -11,6 +11,7 @@
#include <__algorithm/any_of.h>
#include <__algorithm/find_if.h>
+#include <__algorithm/pstl_backends/cpu_backends/backend.h>
#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__atomic/atomic.h>
#include <__atomic/memory_order.h>
@@ -30,7 +31,7 @@ template <class _ExecutionPolicy, class _ForwardIterator, class _Predicate>
_LIBCPP_HIDE_FROM_ABI bool
__pstl_any_of(__omp_backend_tag, _ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) {
// TODO: Implement GPU backend
- return std::any_of(__first, __last, __pred);
+ return std::__pstl_any_of<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __pred);
}
_LIBCPP_END_NAMESPACE_STD
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/fill.h b/libcxx/include/__algorithm/pstl_backends/openmp/fill.h
index 56341b04f0e50df..6098769a4fedb2d 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/fill.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/fill.h
@@ -10,6 +10,7 @@
#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_FILL_H
#include <__algorithm/fill.h>
+#include <__algorithm/pstl_backends/cpu_backends/backend.h>
#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__config>
#include <__iterator/concepts.h>
@@ -39,7 +40,7 @@ __pstl_fill(__omp_backend_tag, _ForwardIterator __first, _ForwardIterator __last
}
// Otherwise, we execute fill on the CPU instead
else {
- std::fill(__first, __last, __value);
+ std::__pstl_fill<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __value);
}
}
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h b/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h
index 1e78cb67cd75978..6cd3b808e0700cc 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h
@@ -10,6 +10,7 @@
#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_FIND_IF_H
#include <__algorithm/find_if.h>
+#include <__algorithm/pstl_backends/cpu_backends/backend.h>
#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__atomic/atomic.h>
#include <__config>
@@ -33,7 +34,7 @@ template <class _ExecutionPolicy, class _ForwardIterator, class _Predicate>
_LIBCPP_HIDE_FROM_ABI _ForwardIterator
__pstl_find_if(__omp_backend_tag, _ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) {
// TODO: Implement the GPU backend
- return std::find_if(__first, __last, __pred);
+ return std::__pstl_find_if<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __pred);
}
_LIBCPP_END_NAMESPACE_STD
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h b/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h
index 401cdfade50a103..c1a159829989bb1 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h
@@ -10,6 +10,7 @@
#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_FOR_EACH_H
#include <__algorithm/for_each.h>
+#include <__algorithm/pstl_backends/cpu_backends/backend.h>
#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__config>
#include <__iterator/concepts.h>
@@ -35,10 +36,10 @@ __pstl_for_each(__omp_backend_tag, _ForwardIterator __first, _ForwardIterator __
__has_random_access_iterator_category_or_concept<_ForwardIterator>::value &&
__libcpp_is_contiguous_iterator<_ForwardIterator>::value) {
std::__par_backend::__parallel_for_simd_1(__first, __last - __first, __func);
- } else {
- // If it is not safe to offload to the GPU, we call the serial
- // implementation
- std::for_each(__first, __last, __func);
+ }
+ // Else we fall back to the serial backend
+ else {
+ std::__pstl_for_each<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __func);
}
}
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/merge.h b/libcxx/include/__algorithm/pstl_backends/openmp/merge.h
index 23036e1cc853980..b6587b161d15488 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/merge.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/merge.h
@@ -10,6 +10,7 @@
#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_MERGE_H
#include <__algorithm/merge.h>
+#include <__algorithm/pstl_backends/cpu_backends/backend.h>
#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__config>
#include <__iterator/concepts.h>
@@ -39,7 +40,8 @@ _LIBCPP_HIDE_FROM_ABI _ForwardOutIterator __pstl_merge(
_ForwardOutIterator __result,
_Comp __comp) {
// TODO: Implement GPU backend
- return std::merge(__first1, __last1, __first2, __last2, __result, __comp);
+ return std::__pstl_merge<_ExecutionPolicy>(
+ __cpu_backend_tag{}, __first1, __last1, __first2, __last2, __result, __comp);
}
_LIBCPP_END_NAMESPACE_STD
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/stable_sort.h b/libcxx/include/__algorithm/pstl_backends/openmp/stable_sort.h
index 7d28b8de77983a7..ac9323b04f63f90 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/stable_sort.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/stable_sort.h
@@ -9,6 +9,7 @@
#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_STABLE_SORT_H
#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_STABLE_SORT_H
+#include <__algorithm/pstl_backends/cpu_backends/backend.h>
#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__algorithm/stable_sort.h>
#include <__config>
@@ -27,7 +28,7 @@ template <class _ExecutionPolicy, class _RandomAccessIterator, class _Comp>
_LIBCPP_HIDE_FROM_ABI void
__pstl_stable_sort(__omp_backend_tag, _RandomAccessIterator __first, _RandomAccessIterator __last, _Comp __comp) {
// TODO: Implement GPU backend.
- std::stable_sort(__first, __last, __comp);
+ __pstl_stable_sort<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __comp);
}
_LIBCPP_END_NAMESPACE_STD
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/transform.h b/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
index 6dc7ab22c98cc35..f855c5146e0f39b 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
@@ -9,6 +9,7 @@
#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_TRANSFORM_H
#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_TRANSFORM_H
+#include <__algorithm/pstl_backends/cpu_backends/backend.h>
#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__algorithm/transform.h>
#include <__config>
@@ -38,15 +39,12 @@ _LIBCPP_HIDE_FROM_ABI _ForwardOutIterator __pstl_transform(
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__has_random_access_iterator_category_or_concept<_ForwardIterator>::value &&
__has_random_access_iterator_category_or_concept<_ForwardOutIterator>::value &&
-# if _LIBCPP_STD_VER <= 17
- __libcpp_is_contiguous_iterator<_ForwardIterator>::value &&
-# endif
__libcpp_is_contiguous_iterator<_ForwardOutIterator>::value) {
std::__par_backend::__parallel_for_simd_2(__first, __last - __first, __result, __op);
return __result + (__last - __first);
}
- // If it is not safe to offload to the GPU, we rely on the serial backend.
- return std::transform(__first, __last, __result, __op);
+ // If it is not safe to offload to the GPU, we rely on the CPU backend.
+ return std::__pstl_transform<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __result, __op);
}
template <class _ExecutionPolicy,
@@ -71,8 +69,8 @@ _LIBCPP_HIDE_FROM_ABI _ForwardOutIterator __pstl_transform(
std::__par_backend::__parallel_for_simd_3(__first1, __last1 - __first1, __first2, __result, __op);
return __result + (__last1 - __first1);
}
- // If it is not safe to offload to the GPU, we call the serial implementation
- return std::transform(__first1, __last1, __first2, __result, __op);
+ // If it is not safe to offload to the GPU, we rely on the CPU backend.
+ return std::__pstl_transform<_ExecutionPolicy>(__cpu_backend_tag{}, __first1, __last1, __first2, __result, __op);
}
_LIBCPP_END_NAMESPACE_STD
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h b/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h
index c63e456b314c1c8..b34d2be79921a71 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h
@@ -9,6 +9,7 @@
#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_TRANSFORM_REDUCE_H
#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_TRANSFORM_REDUCE_H
+#include <__algorithm/pstl_backends/cpu_backends/backend.h>
#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__config>
#include <__functional/operations.h>
@@ -72,16 +73,13 @@ _LIBCPP_HIDE_FROM_ABI _Tp __pstl_transform_reduce(
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__has_random_access_iterator_category_or_concept<_ForwardIterator1>::value &&
__has_random_access_iterator_category_or_concept<_ForwardIterator2>::value && is_arithmetic_v<_Tp> &&
-# if _LIBCPP_STD_VER <= 17
- __libcpp_is_contiguous_iterator<_ForwardIterator1>::value &&
- __libcpp_is_contiguous_iterator<_ForwardIterator2>::value &&
-# endif
(__is_trivial_plus_operation<_BinaryOperation1, _Tp, _Tp>::value ||
__is_supported_reduction<_BinaryOperation1, _Tp, _Tp>::value)) {
return std::__par_backend::__parallel_for_simd_reduction_2(
__first1, __first2, __last1 - __first1, __init, __reduce, __transform);
}
- return std::transform_reduce(__first1, __last1, __first2, std::move(__init), __reduce, __transform);
+ return std::__pstl_transform_reduce<_ExecutionPolicy>(
+ __cpu_backend_tag{}, __first1, __last1, __first2, std::move(__init), __reduce, __transform);
}
//===----------------------------------------------------------------------===//
@@ -104,8 +102,8 @@ _LIBCPP_HIDE_FROM_ABI _Tp __pstl_transform_reduce(
return std::__par_backend::__parallel_for_simd_reduction_1(
__first, __last - __first, __init, __reduce, __transform);
}
- // If it is not safe to offload to the GPU, we call the serial implementation
- return std::transform_reduce(__first, __last, std::move(__init), __reduce, __transform);
+ return std::__pstl_transform_reduce<_ExecutionPolicy>(
+ __cpu_backend_tag{}, __first, __last, std::move(__init), __reduce, __transform);
}
_LIBCPP_END_NAMESPACE_STD
>From e93331fa79dda22986ab4f4bc2a356d934fa428a Mon Sep 17 00:00:00 2001
From: AntonRydahl <rydahl2610 at gmail.com>
Date: Mon, 9 Oct 2023 11:48:58 -0700
Subject: [PATCH 13/26] Clang-formatted cpu_backend.h and openmp.h
---
.../__algorithm/pstl_backends/cpu_backend.h | 18 ++++++++---------
.../__algorithm/pstl_backends/openmp.h | 20 +++++++++----------
2 files changed, 19 insertions(+), 19 deletions(-)
diff --git a/libcxx/include/__algorithm/pstl_backends/cpu_backend.h b/libcxx/include/__algorithm/pstl_backends/cpu_backend.h
index 50876ed2532eb41..e54f331b9430b68 100644
--- a/libcxx/include/__algorithm/pstl_backends/cpu_backend.h
+++ b/libcxx/include/__algorithm/pstl_backends/cpu_backend.h
@@ -46,14 +46,14 @@
TODO: Document the parallel backend
*/
-# include <__algorithm/pstl_backends/cpu_backends/any_of.h>
-# include <__algorithm/pstl_backends/cpu_backends/backend.h>
-# include <__algorithm/pstl_backends/cpu_backends/fill.h>
-# include <__algorithm/pstl_backends/cpu_backends/find_if.h>
-# include <__algorithm/pstl_backends/cpu_backends/for_each.h>
-# include <__algorithm/pstl_backends/cpu_backends/merge.h>
-# include <__algorithm/pstl_backends/cpu_backends/stable_sort.h>
-# include <__algorithm/pstl_backends/cpu_backends/transform.h>
-# include <__algorithm/pstl_backends/cpu_backends/transform_reduce.h>
+#include <__algorithm/pstl_backends/cpu_backends/any_of.h>
+#include <__algorithm/pstl_backends/cpu_backends/backend.h>
+#include <__algorithm/pstl_backends/cpu_backends/fill.h>
+#include <__algorithm/pstl_backends/cpu_backends/find_if.h>
+#include <__algorithm/pstl_backends/cpu_backends/for_each.h>
+#include <__algorithm/pstl_backends/cpu_backends/merge.h>
+#include <__algorithm/pstl_backends/cpu_backends/stable_sort.h>
+#include <__algorithm/pstl_backends/cpu_backends/transform.h>
+#include <__algorithm/pstl_backends/cpu_backends/transform_reduce.h>
#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_CPU_BACKEND_H
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp.h b/libcxx/include/__algorithm/pstl_backends/openmp.h
index 4c121e187ae246c..6afc43f1faf3567 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp.h
@@ -9,17 +9,17 @@
#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_H
#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_H
-# include <__config>
+#include <__config>
-# include <__algorithm/pstl_backends/openmp/backend.h>
+#include <__algorithm/pstl_backends/openmp/backend.h>
-# include <__algorithm/pstl_backends/openmp/any_of.h>
-# include <__algorithm/pstl_backends/openmp/fill.h>
-# include <__algorithm/pstl_backends/openmp/find_if.h>
-# include <__algorithm/pstl_backends/openmp/for_each.h>
-# include <__algorithm/pstl_backends/openmp/merge.h>
-# include <__algorithm/pstl_backends/openmp/stable_sort.h>
-# include <__algorithm/pstl_backends/openmp/transform.h>
-# include <__algorithm/pstl_backends/openmp/transform_reduce.h>
+#include <__algorithm/pstl_backends/openmp/any_of.h>
+#include <__algorithm/pstl_backends/openmp/fill.h>
+#include <__algorithm/pstl_backends/openmp/find_if.h>
+#include <__algorithm/pstl_backends/openmp/for_each.h>
+#include <__algorithm/pstl_backends/openmp/merge.h>
+#include <__algorithm/pstl_backends/openmp/stable_sort.h>
+#include <__algorithm/pstl_backends/openmp/transform.h>
+#include <__algorithm/pstl_backends/openmp/transform_reduce.h>
#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_H
>From 9ea00c5718d57aa30f634743cf703342e4a105bf Mon Sep 17 00:00:00 2001
From: AntonRydahl <rydahl2610 at gmail.com>
Date: Mon, 9 Oct 2023 17:08:00 -0700
Subject: [PATCH 14/26] Removing unnecessary includes and redundant iterator
checks
---
libcxx/include/__algorithm/pstl_backend.h | 2 +-
.../include/__algorithm/pstl_backends/openmp.h | 6 +++---
.../__algorithm/pstl_backends/openmp/any_of.h | 8 --------
.../__algorithm/pstl_backends/openmp/fill.h | 9 ++-------
.../__algorithm/pstl_backends/openmp/find_if.h | 8 --------
.../__algorithm/pstl_backends/openmp/for_each.h | 4 ----
.../__algorithm/pstl_backends/openmp/merge.h | 4 ----
.../pstl_backends/openmp/stable_sort.h | 2 --
.../pstl_backends/openmp/transform.h | 6 ------
.../pstl_backends/openmp/transform_reduce.h | 17 +++++------------
10 files changed, 11 insertions(+), 55 deletions(-)
diff --git a/libcxx/include/__algorithm/pstl_backend.h b/libcxx/include/__algorithm/pstl_backend.h
index dbd6f4dae8cbefe..14067351c6acbd4 100644
--- a/libcxx/include/__algorithm/pstl_backend.h
+++ b/libcxx/include/__algorithm/pstl_backend.h
@@ -208,7 +208,7 @@ struct __select_backend<std::execution::parallel_unsequenced_policy> {
template <>
struct __select_backend<std::execution::parallel_policy> {
- using type = __omp_backend_tag;
+ using type = __cpu_backend_tag;
};
template <>
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp.h b/libcxx/include/__algorithm/pstl_backends/openmp.h
index 6afc43f1faf3567..9e5490db655f4bd 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp.h
@@ -6,8 +6,8 @@
//
//===----------------------------------------------------------------------===//
-#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_H
-#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_H
+#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_H
+#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_H
#include <__config>
@@ -22,4 +22,4 @@
#include <__algorithm/pstl_backends/openmp/transform.h>
#include <__algorithm/pstl_backends/openmp/transform_reduce.h>
-#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_GPU_BACKEND_H
+#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_H
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/any_of.h b/libcxx/include/__algorithm/pstl_backends/openmp/any_of.h
index a36f545d5bd719b..beae485f41f248d 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/any_of.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/any_of.h
@@ -10,18 +10,10 @@
#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_ANY_OF_H
#include <__algorithm/any_of.h>
-#include <__algorithm/find_if.h>
#include <__algorithm/pstl_backends/cpu_backends/backend.h>
#include <__algorithm/pstl_backends/openmp/backend.h>
-#include <__atomic/atomic.h>
-#include <__atomic/memory_order.h>
#include <__config>
-#include <__functional/operations.h>
-#include <__iterator/concepts.h>
#include <__type_traits/is_execution_policy.h>
-#include <__utility/pair.h>
-#include <__utility/terminate_on_exception.h>
-#include <cstdint>
#if !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/fill.h b/libcxx/include/__algorithm/pstl_backends/openmp/fill.h
index 6098769a4fedb2d..19a3ba3f7be07bd 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/fill.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/fill.h
@@ -13,11 +13,7 @@
#include <__algorithm/pstl_backends/cpu_backends/backend.h>
#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__config>
-#include <__iterator/concepts.h>
-#include <__iterator/iterator_traits.h>
#include <__type_traits/is_execution_policy.h>
-#include <__utility/terminate_on_exception.h>
-#include <stdio.h>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
@@ -31,10 +27,9 @@ template <class _ExecutionPolicy, class _ForwardIterator, class _Tp>
_LIBCPP_HIDE_FROM_ABI void
__pstl_fill(__omp_backend_tag, _ForwardIterator __first, _ForwardIterator __last, const _Tp& __value) {
// It is only safe to execute fill on the GPU, it the execution policy is
- // parallel unsequenced, as it is the only execution policy prohibiting throwing
- // exceptions and allowing SIMD instructions
+ // parallel unsequenced, as it is the only execution policy allowing
+ // SIMD instructions
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
- __has_random_access_iterator_category_or_concept<_ForwardIterator>::value &&
__libcpp_is_contiguous_iterator<_ForwardIterator>::value) {
std::__par_backend::__parallel_for_simd_val_1(__first, __last - __first, __value);
}
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h b/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h
index 6cd3b808e0700cc..4526d3976567a07 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h
@@ -12,15 +12,7 @@
#include <__algorithm/find_if.h>
#include <__algorithm/pstl_backends/cpu_backends/backend.h>
#include <__algorithm/pstl_backends/openmp/backend.h>
-#include <__atomic/atomic.h>
#include <__config>
-#include <__functional/operations.h>
-#include <__iterator/concepts.h>
-#include <__iterator/iterator_traits.h>
-#include <__type_traits/is_execution_policy.h>
-#include <__utility/pair.h>
-#include <__utility/terminate_on_exception.h>
-#include <cstddef>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h b/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h
index c1a159829989bb1..30c2e5cca2f2649 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h
@@ -13,10 +13,7 @@
#include <__algorithm/pstl_backends/cpu_backends/backend.h>
#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__config>
-#include <__iterator/concepts.h>
#include <__type_traits/is_execution_policy.h>
-#include <__utility/terminate_on_exception.h>
-#include <stdio.h>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
@@ -33,7 +30,6 @@ __pstl_for_each(__omp_backend_tag, _ForwardIterator __first, _ForwardIterator __
// parallel unsequenced, as it is the only execution policy prohibiting throwing
// exceptions and allowing SIMD instructions
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
- __has_random_access_iterator_category_or_concept<_ForwardIterator>::value &&
__libcpp_is_contiguous_iterator<_ForwardIterator>::value) {
std::__par_backend::__parallel_for_simd_1(__first, __last - __first, __func);
}
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/merge.h b/libcxx/include/__algorithm/pstl_backends/openmp/merge.h
index b6587b161d15488..666c3a0e0001933 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/merge.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/merge.h
@@ -13,10 +13,6 @@
#include <__algorithm/pstl_backends/cpu_backends/backend.h>
#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__config>
-#include <__iterator/concepts.h>
-#include <__type_traits/is_execution_policy.h>
-#include <__utility/move.h>
-#include <__utility/terminate_on_exception.h>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/stable_sort.h b/libcxx/include/__algorithm/pstl_backends/openmp/stable_sort.h
index ac9323b04f63f90..46e48dd279e89bd 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/stable_sort.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/stable_sort.h
@@ -13,8 +13,6 @@
#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__algorithm/stable_sort.h>
#include <__config>
-#include <__type_traits/is_execution_policy.h>
-#include <__utility/terminate_on_exception.h>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/transform.h b/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
index f855c5146e0f39b..e507a16eac965b0 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
@@ -14,11 +14,7 @@
#include <__algorithm/transform.h>
#include <__config>
#include <__iterator/concepts.h>
-#include <__iterator/iterator_traits.h>
-#include <__type_traits/enable_if.h>
#include <__type_traits/is_execution_policy.h>
-#include <__type_traits/remove_cvref.h>
-#include <__utility/terminate_on_exception.h>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
@@ -38,7 +34,6 @@ _LIBCPP_HIDE_FROM_ABI _ForwardOutIterator __pstl_transform(
// The interface for the function switched between C++17 and C++20
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__has_random_access_iterator_category_or_concept<_ForwardIterator>::value &&
- __has_random_access_iterator_category_or_concept<_ForwardOutIterator>::value &&
__libcpp_is_contiguous_iterator<_ForwardOutIterator>::value) {
std::__par_backend::__parallel_for_simd_2(__first, __last - __first, __result, __op);
return __result + (__last - __first);
@@ -64,7 +59,6 @@ _LIBCPP_HIDE_FROM_ABI _ForwardOutIterator __pstl_transform(
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__has_random_access_iterator_category_or_concept<_ForwardIterator1>::value &&
__has_random_access_iterator_category_or_concept<_ForwardIterator2>::value &&
- __has_random_access_iterator_category_or_concept<_ForwardOutIterator>::value &&
__libcpp_is_contiguous_iterator<_ForwardOutIterator>::value) {
std::__par_backend::__parallel_for_simd_3(__first1, __last1 - __first1, __first2, __result, __op);
return __result + (__last1 - __first1);
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h b/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h
index b34d2be79921a71..eb0a7ba52d8fdcc 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h
@@ -12,17 +12,12 @@
#include <__algorithm/pstl_backends/cpu_backends/backend.h>
#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__config>
-#include <__functional/operations.h>
#include <__iterator/concepts.h>
-#include <__iterator/iterator_traits.h>
#include <__numeric/transform_reduce.h>
#include <__type_traits/integral_constant.h>
#include <__type_traits/is_arithmetic.h>
#include <__type_traits/is_execution_policy.h>
#include <__type_traits/operation_traits.h>
-#include <__utility/move.h>
-#include <__utility/terminate_on_exception.h>
-#include <new>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
@@ -33,13 +28,13 @@
_LIBCPP_BEGIN_NAMESPACE_STD
template <class _T1, class _T2, class _T3>
-struct _LIBCPP_HIDE_FROM_ABI __is_supported_reduction : std::false_type {};
+struct __is_supported_reduction : std::false_type {};
# define __PSTL_IS_SUPPORTED_REDUCTION(funname) \
template <class _Tp> \
- struct _LIBCPP_HIDE_FROM_ABI __is_supported_reduction<std::funname<_Tp>, _Tp, _Tp> : std::true_type {}; \
+ struct __is_supported_reduction<std::funname<_Tp>, _Tp, _Tp> : std::true_type {}; \
template <class _Tp, class _Up> \
- struct _LIBCPP_HIDE_FROM_ABI __is_supported_reduction<std::funname<>, _Tp, _Up> : std::true_type {};
+ struct __is_supported_reduction<std::funname<>, _Tp, _Up> : std::true_type {};
// __is_trivial_plus_operation already exists
__PSTL_IS_SUPPORTED_REDUCTION(plus)
@@ -73,8 +68,7 @@ _LIBCPP_HIDE_FROM_ABI _Tp __pstl_transform_reduce(
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__has_random_access_iterator_category_or_concept<_ForwardIterator1>::value &&
__has_random_access_iterator_category_or_concept<_ForwardIterator2>::value && is_arithmetic_v<_Tp> &&
- (__is_trivial_plus_operation<_BinaryOperation1, _Tp, _Tp>::value ||
- __is_supported_reduction<_BinaryOperation1, _Tp, _Tp>::value)) {
+ __is_supported_reduction<_BinaryOperation1, _Tp, _Tp>::value) {
return std::__par_backend::__parallel_for_simd_reduction_2(
__first1, __first2, __last1 - __first1, __init, __reduce, __transform);
}
@@ -97,8 +91,7 @@ _LIBCPP_HIDE_FROM_ABI _Tp __pstl_transform_reduce(
// The interface for the function switched between C++17 and C++20
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__has_random_access_iterator_category_or_concept<_ForwardIterator>::value && is_arithmetic_v<_Tp> &&
- (__is_trivial_plus_operation<_BinaryOperation, _Tp, _Tp>::value ||
- __is_supported_reduction<_BinaryOperation, _Tp, _Tp>::value)) {
+ __is_supported_reduction<_BinaryOperation, _Tp, _Tp>::value) {
return std::__par_backend::__parallel_for_simd_reduction_1(
__first, __last - __first, __init, __reduce, __transform);
}
>From 1adc6aaa4b9bd8a44b2e68bbd6878131dde2b5d6 Mon Sep 17 00:00:00 2001
From: AntonRydahl <rydahl2610 at gmail.com>
Date: Mon, 16 Oct 2023 01:06:48 -0700
Subject: [PATCH 15/26] Adding optional to OpenMP backend and other
refactorings requested during code review
---
.../__algorithm/pstl_backends/openmp/any_of.h | 3 +-
.../__algorithm/pstl_backends/openmp/fill.h | 32 ++-
.../pstl_backends/openmp/find_if.h | 39 +++-
.../pstl_backends/openmp/for_each.h | 33 +++-
.../__algorithm/pstl_backends/openmp/merge.h | 3 +-
.../pstl_backends/openmp/omp_offload.h | 185 +++---------------
.../pstl_backends/openmp/stable_sort.h | 6 +-
.../pstl_backends/openmp/transform.h | 93 ++++++++-
.../pstl_backends/openmp/transform_reduce.h | 16 +-
9 files changed, 225 insertions(+), 185 deletions(-)
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/any_of.h b/libcxx/include/__algorithm/pstl_backends/openmp/any_of.h
index beae485f41f248d..65f2294ff2ee5fe 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/any_of.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/any_of.h
@@ -14,13 +14,14 @@
#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__config>
#include <__type_traits/is_execution_policy.h>
+#include <optional>
#if !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
_LIBCPP_BEGIN_NAMESPACE_STD
template <class _ExecutionPolicy, class _ForwardIterator, class _Predicate>
-_LIBCPP_HIDE_FROM_ABI bool
+_LIBCPP_HIDE_FROM_ABI optional<bool>
__pstl_any_of(__omp_backend_tag, _ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) {
// TODO: Implement GPU backend
return std::__pstl_any_of<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __pred);
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/fill.h b/libcxx/include/__algorithm/pstl_backends/openmp/fill.h
index 19a3ba3f7be07bd..250e514b4d526fd 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/fill.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/fill.h
@@ -14,6 +14,8 @@
#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__config>
#include <__type_traits/is_execution_policy.h>
+#include <__utility/empty.h>
+#include <optional>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
@@ -23,19 +25,43 @@
_LIBCPP_BEGIN_NAMESPACE_STD
+namespace __par_backend {
+inline namespace __omp_gpu_backend {
+
+template <class _Tp, class _DifferenceType, class _Up>
+_LIBCPP_HIDE_FROM_ABI optional<__empty> __omp_parallel_for_simd_val(
+ _Tp* __first, _DifferenceType __n, const _Up& __value) noexcept {
+ __omp_gpu_backend::__omp_map_alloc(__first, __n);
+# pragma omp target teams distribute parallel for simd firstprivate(__value)
+ for (_DifferenceType __i = 0; __i < __n; ++__i)
+ *(__first+__i) = __value;
+ __omp_gpu_backend::__omp_map_from(__first, __n);
+ return __empty{};
+}
+
+template <class _ForwardIterator, class _DifferenceType, class _Tp>
+_LIBCPP_HIDE_FROM_ABI optional<__empty>
+__parallel_for_simd_val(_ForwardIterator __first, _DifferenceType __n, const _Tp& __value) noexcept {
+ return __omp_gpu_backend::__omp_parallel_for_simd_val(__omp_gpu_backend::__omp_extract_base_ptr(__first), __n, __value);
+}
+
+}
+}
+
template <class _ExecutionPolicy, class _ForwardIterator, class _Tp>
-_LIBCPP_HIDE_FROM_ABI void
+_LIBCPP_HIDE_FROM_ABI optional<__empty>
__pstl_fill(__omp_backend_tag, _ForwardIterator __first, _ForwardIterator __last, const _Tp& __value) {
// It is only safe to execute fill on the GPU, it the execution policy is
// parallel unsequenced, as it is the only execution policy allowing
// SIMD instructions
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
+ __is_parallel_execution_policy_v<_ExecutionPolicy> &&
__libcpp_is_contiguous_iterator<_ForwardIterator>::value) {
- std::__par_backend::__parallel_for_simd_val_1(__first, __last - __first, __value);
+ return std::__par_backend::__parallel_for_simd_val(__first, __last - __first, __value);
}
// Otherwise, we execute fill on the CPU instead
else {
- std::__pstl_fill<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __value);
+ return std::__pstl_fill<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __value);
}
}
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h b/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h
index 4526d3976567a07..94f7c42953c2a4a 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h
@@ -13,6 +13,7 @@
#include <__algorithm/pstl_backends/cpu_backends/backend.h>
#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__config>
+#include <optional>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
@@ -22,11 +23,43 @@
_LIBCPP_BEGIN_NAMESPACE_STD
+namespace __par_backend {
+inline namespace __omp_gpu_backend {
+
+template <class _Tp, class _DifferenceType, class _Predicate>
+_LIBCPP_HIDE_FROM_ABI _DifferenceType __omp_parallel_for_min_idx(_Tp* __first, _DifferenceType __n, _Predicate __pred) noexcept {
+ __omp_gpu_backend::__omp_map_to(__first, __n);
+ _DifferenceType idx = __n;
+# pragma omp target teams distribute parallel for simd reduction(min:idx)
+ for (_DifferenceType __i = 0; __i < __n; ++__i){
+ if (__pred(*(__first+__i))) {
+ idx = (__i < idx) ? __i : idx;
+ }
+ }
+ __omp_gpu_backend::__omp_map_free(__first, __n);
+ return idx;
+}
+
+// Extracting the underlying pointer
+
+template <class _ForwardIterator, class _DifferenceType, class _Predicate>
+_LIBCPP_HIDE_FROM_ABI optional<_ForwardIterator> __parallel_for_min_idx(_ForwardIterator __first, _DifferenceType __n, _Predicate __pred) noexcept {
+ return __first + __omp_gpu_backend::__omp_parallel_for_min_idx(__omp_gpu_backend::__omp_extract_base_ptr(__first), __n, __pred);
+}
+
+}
+}
+
template <class _ExecutionPolicy, class _ForwardIterator, class _Predicate>
-_LIBCPP_HIDE_FROM_ABI _ForwardIterator
+_LIBCPP_HIDE_FROM_ABI optional<_ForwardIterator>
__pstl_find_if(__omp_backend_tag, _ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) {
- // TODO: Implement the GPU backend
- return std::__pstl_find_if<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __pred);
+ if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
+ __is_parallel_execution_policy_v<_ExecutionPolicy> &&
+ __libcpp_is_contiguous_iterator<_ForwardIterator>::value) {
+ return __par_backend::__parallel_for_min_idx(__first, __last - __first, __pred);
+ } else {
+ return std::__pstl_find_if<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __pred);
+ }
}
_LIBCPP_END_NAMESPACE_STD
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h b/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h
index 30c2e5cca2f2649..444352b4a5e51a8 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h
@@ -14,6 +14,8 @@
#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__config>
#include <__type_traits/is_execution_policy.h>
+#include <optional>
+#include <__utility/empty.h>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
@@ -23,19 +25,44 @@
_LIBCPP_BEGIN_NAMESPACE_STD
+namespace __par_backend {
+inline namespace __omp_gpu_backend {
+
+template <class _Tp, class _DifferenceType, class _Function>
+_LIBCPP_HIDE_FROM_ABI optional<__empty> __omp_parallel_for_simd(
+ _Tp* __first, _DifferenceType __n, _Function __f) noexcept {
+ __omp_gpu_backend::__omp_map_to(__first, __n);
+# pragma omp target teams distribute parallel for simd
+ for (_DifferenceType __i = 0; __i < __n; ++__i)
+ __f(*(__first+__i));
+ __omp_gpu_backend::__omp_map_from(__first, __n);
+ return __empty{};
+}
+
+// Extracting the underlying pointer
+
+template <class _ForwardIterator, class _DifferenceType, class _Function>
+_LIBCPP_HIDE_FROM_ABI optional<__empty> __parallel_for_simd_1(_ForwardIterator __first, _DifferenceType __n, _Function __f) noexcept {
+ return __omp_gpu_backend::__omp_parallel_for_simd(__omp_gpu_backend::__omp_extract_base_ptr(__first), __n, __f);
+}
+
+}
+}
+
template <class _ExecutionPolicy, class _ForwardIterator, class _Functor>
-_LIBCPP_HIDE_FROM_ABI void
+_LIBCPP_HIDE_FROM_ABI optional<__empty>
__pstl_for_each(__omp_backend_tag, _ForwardIterator __first, _ForwardIterator __last, _Functor __func) {
// It is only safe to execute for_each on the GPU, it the execution policy is
// parallel unsequenced, as it is the only execution policy prohibiting throwing
// exceptions and allowing SIMD instructions
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
+ __libcpp_is_contiguous_iterator<_ForwardIterator>::value &&
__libcpp_is_contiguous_iterator<_ForwardIterator>::value) {
- std::__par_backend::__parallel_for_simd_1(__first, __last - __first, __func);
+ return std::__par_backend::__parallel_for_simd_1(__first, __last - __first, __func);
}
// Else we fall back to the serial backend
else {
- std::__pstl_for_each<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __func);
+ return std::__pstl_for_each<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __func);
}
}
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/merge.h b/libcxx/include/__algorithm/pstl_backends/openmp/merge.h
index 666c3a0e0001933..8fff9125add191d 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/merge.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/merge.h
@@ -13,6 +13,7 @@
#include <__algorithm/pstl_backends/cpu_backends/backend.h>
#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__config>
+#include <optional>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
@@ -27,7 +28,7 @@ template <class _ExecutionPolicy,
class _ForwardIterator2,
class _ForwardOutIterator,
class _Comp>
-_LIBCPP_HIDE_FROM_ABI _ForwardOutIterator __pstl_merge(
+_LIBCPP_HIDE_FROM_ABI optional<_ForwardOutIterator> __pstl_merge(
__omp_backend_tag,
_ForwardIterator1 __first1,
_ForwardIterator1 __last1,
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/omp_offload.h b/libcxx/include/__algorithm/pstl_backends/openmp/omp_offload.h
index ee0bfe13bac9010..77afb35ee71b4bb 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/omp_offload.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/omp_offload.h
@@ -10,6 +10,7 @@
#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_OMP_OFFLOAD_H
#include <__assert>
+#include <__algorithm/unwrap_iter.h>
#include <__config>
#include <__functional/operations.h>
#include <__iterator/iterator_traits.h>
@@ -19,7 +20,9 @@
#include <__type_traits/is_pointer.h>
#include <__type_traits/is_same.h>
#include <__utility/move.h>
+#include <__utility/empty.h>
#include <cstddef>
+#include <optional>
// is_same
@@ -39,13 +42,15 @@ _LIBCPP_BEGIN_NAMESPACE_STD
namespace __par_backend {
inline namespace __omp_gpu_backend {
+//===----------------------------------------------------------------------===//
// Functions for eaxtracting the pase pointers
+//===----------------------------------------------------------------------===//
// In the general case we do not need to extract it. This is for instance the
// case for pointers.
template <typename _Tp>
_LIBCPP_HIDE_FROM_ABI inline auto __omp_extract_base_ptr(_Tp p) noexcept {
- return p;
+ return std::__unwrap_iter(p);
}
// For vectors and arrays, etc, we need to extract the underlying base pointer.
@@ -64,159 +69,29 @@ _LIBCPP_HIDE_FROM_ABI inline _Tp __omp_extract_base_ptr(std::__wrap_iter<_Tp> w)
template <class _Iterator, class _DifferenceType>
_LIBCPP_HIDE_FROM_ABI void
__omp_map_to([[maybe_unused]] const _Iterator p, [[maybe_unused]] const _DifferenceType len) noexcept {
- if constexpr (__libcpp_is_contiguous_iterator<_Iterator>::value) {
-# pragma omp target enter data map(to : p[0 : len])
- } else {
-# pragma omp target enter data map(to : p)
- }
+ static_assert(__libcpp_is_contiguous_iterator<_Iterator>::value);
+#pragma omp target enter data map(to : p[0 : len])
}
template <class _Iterator, class _DifferenceType>
_LIBCPP_HIDE_FROM_ABI void
__omp_map_from([[maybe_unused]] const _Iterator p, [[maybe_unused]] const _DifferenceType len) noexcept {
- if constexpr (__libcpp_is_contiguous_iterator<_Iterator>::value) {
-# pragma omp target exit data map(from : p[0 : len])
- } else {
-# pragma omp target exit data map(release : p)
- }
+ static_assert(__libcpp_is_contiguous_iterator<_Iterator>::value);
+#pragma omp target exit data map(from : p[0 : len])
}
template <class _Iterator, class _DifferenceType>
_LIBCPP_HIDE_FROM_ABI void
__omp_map_alloc([[maybe_unused]] const _Iterator p, [[maybe_unused]] const _DifferenceType len) noexcept {
- if constexpr (__libcpp_is_contiguous_iterator<_Iterator>::value) {
-# pragma omp target enter data map(alloc : p[0 : len])
- } else {
-# pragma omp target enter data map(to : p)
- }
+ static_assert(__libcpp_is_contiguous_iterator<_Iterator>::value);
+#pragma omp target enter data map(alloc : p[0 : len])
}
template <class _Iterator, class _DifferenceType>
_LIBCPP_HIDE_FROM_ABI void
__omp_map_free([[maybe_unused]] const _Iterator p, [[maybe_unused]] const _DifferenceType len) noexcept {
- if constexpr (__libcpp_is_contiguous_iterator<_Iterator>::value) {
-# pragma omp target exit data map(release : p[0 : len])
- } else {
-# pragma omp target exit data map(release : p)
- }
-}
-
-//===----------------------------------------------------------------------===//
-// Templates for one iterator
-//===----------------------------------------------------------------------===//
-
-// Applying function or lambda in a loop
-
-template <class _Iterator, class _DifferenceType, class _Function>
-_LIBCPP_HIDE_FROM_ABI _Iterator __omp_parallel_for_simd_1(
- _Iterator __first, _DifferenceType __n, _Function __f, [[maybe_unused]] const int __device = 0) noexcept {
- __omp_map_to(__first, __n);
-# pragma omp target teams distribute parallel for simd device(__device)
- for (_DifferenceType __i = 0; __i < __n; ++__i)
- __f(__first[__i]);
- __omp_map_from(__first, __n);
-
- return __first + __n;
-}
-
-// Extracting the underlying pointer
-
-template <class _Iterator, class _DifferenceType, class _Function>
-_LIBCPP_HIDE_FROM_ABI _Iterator __parallel_for_simd_1(_Iterator __first, _DifferenceType __n, _Function __f) noexcept {
- __omp_parallel_for_simd_1(__omp_gpu_backend::__omp_extract_base_ptr(__first), __n, __f);
- return __first + __n;
-}
-
-// Assigning a value in a loop
-
-template <class _Index, class _DifferenceType, class _Tp>
-_LIBCPP_HIDE_FROM_ABI _Index __omp_parallel_for_simd_val_1(
- _Index __first, _DifferenceType __n, const _Tp& __value, [[maybe_unused]] const int __device = 0) noexcept {
- __omp_map_alloc(__first, __n);
-# pragma omp target teams distribute parallel for simd firstprivate(__value) device(__device)
- for (_DifferenceType __i = 0; __i < __n; ++__i)
- __first[__i] = __value;
- __omp_map_from(__first, __n);
- return __first + __n;
-}
-
-template <class _Index, class _DifferenceType, class _Tp>
-_LIBCPP_HIDE_FROM_ABI _Index
-__parallel_for_simd_val_1(_Index __first, _DifferenceType __n, const _Tp& __value) noexcept {
- __omp_parallel_for_simd_val_1(__omp_gpu_backend::__omp_extract_base_ptr(__first), __n, __value);
- return __first + __n;
-}
-
-//===----------------------------------------------------------------------===//
-// Templates for two iterators
-//===----------------------------------------------------------------------===//
-
-template <class _Iterator1, class _DifferenceType, class _Iterator2, class _Function>
-_LIBCPP_HIDE_FROM_ABI _Iterator1 __omp_parallel_for_simd_2(
- _Iterator1 __first1,
- _DifferenceType __n,
- _Iterator2 __first2,
- _Function __f,
- [[maybe_unused]] const int __device = 0) noexcept {
- __omp_map_alloc(__first2, __n);
- __omp_map_to(__first1, __n);
-# pragma omp target teams distribute parallel for simd device(__device)
- for (_DifferenceType __i = 0; __i < __n; ++__i)
- *(__first2 + __i) = __f(*(__first1 + __i));
- __omp_map_from(__first2, __n);
- __omp_map_free(__first1, __n);
- return __first1 + __n;
-}
-
-// Extracting the underlying pointer
-
-template <class _Iterator1, class _DifferenceType, class _Iterator2, class _Function>
-_LIBCPP_HIDE_FROM_ABI _Iterator1
-__parallel_for_simd_2(_Iterator1 __first1, _DifferenceType __n, _Iterator2 __first2, _Function __f) noexcept {
- __omp_parallel_for_simd_2(
- __omp_gpu_backend::__omp_extract_base_ptr(__first1),
- __n,
- __omp_gpu_backend::__omp_extract_base_ptr(__first2),
- __f);
- return __first1 + __n;
-}
-
-//===----------------------------------------------------------------------===//
-// Templates for three iterator
-//===----------------------------------------------------------------------===//
-
-template <class _Iterator1, class _DifferenceType, class _Iterator2, class _Iterator3, class _Function>
-_LIBCPP_HIDE_FROM_ABI _Iterator1 __omp_parallel_for_simd_3(
- _Iterator1 __first1,
- _DifferenceType __n,
- _Iterator2 __first2,
- _Iterator3 __first3,
- _Function __f,
- [[maybe_unused]] const int __device = 0) noexcept {
- __omp_map_to(__first1, __n);
- __omp_map_to(__first2, __n);
- __omp_map_alloc(__first3, __n);
-# pragma omp target teams distribute parallel for simd device(__device)
- for (_DifferenceType __i = 0; __i < __n; ++__i)
- *(__first3 + __i) = __f(*(__first1 + __i), *(__first2 + __i));
- __omp_map_free(__first1, __n);
- __omp_map_free(__first2, __n);
- __omp_map_from(__first3, __n);
- return __first1 + __n;
-}
-
-// Extracting the underlying pointer
-
-template <class _Iterator1, class _DifferenceType, class _Iterator2, class _Iterator3, class _Function>
-_LIBCPP_HIDE_FROM_ABI _Iterator1 __parallel_for_simd_3(
- _Iterator1 __first1, _DifferenceType __n, _Iterator2 __first2, _Iterator3 __first3, _Function __f) noexcept {
- __omp_parallel_for_simd_3(
- __omp_gpu_backend::__omp_extract_base_ptr(__first1),
- __n,
- __omp_gpu_backend::__omp_extract_base_ptr(__first2),
- __omp_gpu_backend::__omp_extract_base_ptr(__first3),
- __f);
- return __first1 + __n;
+ static_assert(__libcpp_is_contiguous_iterator<_Iterator>::value);
+#pragma omp target exit data map(release : p[0 : len])
}
//===----------------------------------------------------------------------===//
@@ -237,13 +112,12 @@ _LIBCPP_HIDE_FROM_ABI _Iterator1 __parallel_for_simd_3(
_DifferenceType __n, \
_Tp __init, \
std_op<_BinaryOperationType> __reduce, \
- _UnaryOperation __transform, \
- [[maybe_unused]] const int __device = 0) noexcept { \
- __omp_map_to(__first, __n); \
-_PSTL_PRAGMA(omp target teams distribute parallel for simd reduction(omp_op:__init) device(__device)) \
+ _UnaryOperation __transform) noexcept { \
+ __omp_gpu_backend::__omp_map_to(__first, __n); \
+_PSTL_PRAGMA(omp target teams distribute parallel for simd reduction(omp_op:__init)) \
for (_DifferenceType __i = 0; __i < __n; ++__i) \
__init = __reduce(__init, __transform(*(__first + __i))); \
- __omp_map_free(__first, __n); \
+ __omp_gpu_backend::__omp_map_free(__first, __n); \
return __init; \
}
@@ -260,15 +134,14 @@ _PSTL_PRAGMA(omp target teams distribute parallel for simd reduction(omp_op:__in
_DifferenceType __n, \
_Tp __init, \
std_op<_BinaryOperationType> __reduce, \
- _UnaryOperation __transform, \
- [[maybe_unused]] const int __device = 0) noexcept { \
- __omp_map_to(__first1, __n); \
- __omp_map_to(__first2, __n); \
-_PSTL_PRAGMA(omp target teams distribute parallel for simd reduction(omp_op:__init) device(__device)) \
+ _UnaryOperation __transform) noexcept { \
+ __omp_gpu_backend::__omp_map_to(__first1, __n); \
+ __omp_gpu_backend::__omp_map_to(__first2, __n); \
+_PSTL_PRAGMA(omp target teams distribute parallel for simd reduction(omp_op:__init)) \
for (_DifferenceType __i = 0; __i < __n; ++__i) \
__init = __reduce(__init, __transform(*(__first1 + __i), *(__first2 + __i))); \
- __omp_map_free(__first1, __n); \
- __omp_map_free(__first2, __n); \
+ __omp_gpu_backend::__omp_map_free(__first1, __n); \
+ __omp_gpu_backend::__omp_map_free(__first2, __n); \
return __init; \
} // namespace __omp_gpu_backend
@@ -308,9 +181,8 @@ _LIBCPP_HIDE_FROM_ABI _Tp __parallel_for_simd_reduction_1(
_DifferenceType __n,
_Tp __init,
_BinaryOperation __reduce,
- _UnaryOperation __transform,
- [[maybe_unused]] const int __device = 0) noexcept {
- return __omp_parallel_for_simd_reduction_1(
+ _UnaryOperation __transform) noexcept {
+ return __omp_gpu_backend::__omp_parallel_for_simd_reduction_1(
__omp_gpu_backend::__omp_extract_base_ptr(__first), __n, __init, __reduce, __transform);
}
@@ -326,9 +198,8 @@ _LIBCPP_HIDE_FROM_ABI _Tp __parallel_for_simd_reduction_2(
_DifferenceType __n,
_Tp __init,
_BinaryOperation __reduce,
- _UnaryOperation __transform,
- [[maybe_unused]] const int __device = 0) noexcept {
- return __omp_parallel_for_simd_reduction_2(
+ _UnaryOperation __transform) noexcept {
+ return __omp_gpu_backend::__omp_parallel_for_simd_reduction_2(
__omp_gpu_backend::__omp_extract_base_ptr(__first1),
__omp_gpu_backend::__omp_extract_base_ptr(__first2),
__n,
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/stable_sort.h b/libcxx/include/__algorithm/pstl_backends/openmp/stable_sort.h
index 46e48dd279e89bd..a4c6a2bff9f92fd 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/stable_sort.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/stable_sort.h
@@ -13,6 +13,8 @@
#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__algorithm/stable_sort.h>
#include <__config>
+#include <__utility/empty.h>
+#include <optional>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
@@ -23,10 +25,10 @@
_LIBCPP_BEGIN_NAMESPACE_STD
template <class _ExecutionPolicy, class _RandomAccessIterator, class _Comp>
-_LIBCPP_HIDE_FROM_ABI void
+_LIBCPP_HIDE_FROM_ABI optional<__empty>
__pstl_stable_sort(__omp_backend_tag, _RandomAccessIterator __first, _RandomAccessIterator __last, _Comp __comp) {
// TODO: Implement GPU backend.
- __pstl_stable_sort<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __comp);
+ return __pstl_stable_sort<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __comp);
}
_LIBCPP_END_NAMESPACE_STD
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/transform.h b/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
index e507a16eac965b0..b29a479c17887c7 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
@@ -15,6 +15,7 @@
#include <__config>
#include <__iterator/concepts.h>
#include <__type_traits/is_execution_policy.h>
+#include <optional>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
@@ -24,18 +25,92 @@
_LIBCPP_BEGIN_NAMESPACE_STD
+namespace __par_backend {
+inline namespace __omp_gpu_backend {
+
+//===----------------------------------------------------------------------===//
+// Templates for two iterators
+//===----------------------------------------------------------------------===//
+
+template <class _Tp, class _DifferenceType, class _Up, class _Function>
+_LIBCPP_HIDE_FROM_ABI optional<__empty> __omp_parallel_for_simd(
+ _Tp* __first1,
+ _DifferenceType __n,
+ _Up* __first2,
+ _Function __f) noexcept {
+ __omp_gpu_backend::__omp_map_alloc(__first2, __n);
+ __omp_gpu_backend::__omp_map_to(__first1, __n);
+# pragma omp target teams distribute parallel for simd
+ for (_DifferenceType __i = 0; __i < __n; ++__i)
+ *(__first2 + __i) = __f(*(__first1 + __i));
+ __omp_gpu_backend::__omp_map_from(__first2, __n);
+ __omp_gpu_backend::__omp_map_free(__first1, __n);
+ return __empty{};
+}
+
+// Extracting the underlying pointer
+
+template <class _Iterator1, class _DifferenceType, class _Iterator2, class _Function>
+_LIBCPP_HIDE_FROM_ABI optional<__empty>
+__parallel_for_simd(_Iterator1 __first1, _DifferenceType __n, _Iterator2 __first2, _Function __f) noexcept {
+ return __omp_gpu_backend::__omp_parallel_for_simd(
+ __omp_gpu_backend::__omp_extract_base_ptr(__first1),
+ __n,
+ __omp_gpu_backend::__omp_extract_base_ptr(__first2),
+ __f);
+}
+
+//===----------------------------------------------------------------------===//
+// Templates for three iterator
+//===----------------------------------------------------------------------===//
+
+template <class _Tp, class _DifferenceType, class _Up, class _Vp, class _Function>
+_LIBCPP_HIDE_FROM_ABI optional<__empty> __omp_parallel_for_simd(
+ _Tp* __first1,
+ _DifferenceType __n,
+ _Up* __first2,
+ _Vp* __first3,
+ _Function __f) noexcept {
+ __omp_gpu_backend::__omp_map_to(__first1, __n);
+ __omp_gpu_backend::__omp_map_to(__first2, __n);
+ __omp_gpu_backend::__omp_map_alloc(__first3, __n);
+# pragma omp target teams distribute parallel for simd
+ for (_DifferenceType __i = 0; __i < __n; ++__i)
+ *(__first3 + __i) = __f(*(__first1 + __i), *(__first2 + __i));
+ __omp_gpu_backend::__omp_map_free(__first1, __n);
+ __omp_gpu_backend::__omp_map_free(__first2, __n);
+ __omp_gpu_backend::__omp_map_from(__first3, __n);
+ return __empty{};
+}
+
+// Extracting the underlying pointer
+
+template <class _Iterator1, class _DifferenceType, class _Iterator2, class _Iterator3, class _Function>
+_LIBCPP_HIDE_FROM_ABI optional<__empty> __parallel_for_simd(
+ _Iterator1 __first1, _DifferenceType __n, _Iterator2 __first2, _Iterator3 __first3, _Function __f) noexcept {
+ return __omp_gpu_backend::__omp_parallel_for_simd(
+ __omp_gpu_backend::__omp_extract_base_ptr(__first1),
+ __n,
+ __omp_gpu_backend::__omp_extract_base_ptr(__first2),
+ __omp_gpu_backend::__omp_extract_base_ptr(__first3),
+ __f);
+}
+
+}
+}
+
template <class _ExecutionPolicy, class _ForwardIterator, class _ForwardOutIterator, class _UnaryOperation>
-_LIBCPP_HIDE_FROM_ABI _ForwardOutIterator __pstl_transform(
+_LIBCPP_HIDE_FROM_ABI optional<_ForwardOutIterator> __pstl_transform(
__omp_backend_tag,
_ForwardIterator __first,
_ForwardIterator __last,
_ForwardOutIterator __result,
_UnaryOperation __op) {
- // The interface for the function switched between C++17 and C++20
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
- __has_random_access_iterator_category_or_concept<_ForwardIterator>::value &&
+ __is_parallel_execution_policy_v<_ExecutionPolicy> &&
+ __libcpp_is_contiguous_iterator<_ForwardIterator>::value &&
__libcpp_is_contiguous_iterator<_ForwardOutIterator>::value) {
- std::__par_backend::__parallel_for_simd_2(__first, __last - __first, __result, __op);
+ std::__par_backend::__parallel_for_simd(__first, __last - __first, __result, __op);
return __result + (__last - __first);
}
// If it is not safe to offload to the GPU, we rely on the CPU backend.
@@ -48,19 +123,19 @@ template <class _ExecutionPolicy,
class _ForwardOutIterator,
class _BinaryOperation,
enable_if_t<is_execution_policy_v<__remove_cvref_t<_ExecutionPolicy>>, int> = 0>
-_LIBCPP_HIDE_FROM_ABI _ForwardOutIterator __pstl_transform(
+_LIBCPP_HIDE_FROM_ABI optional<_ForwardOutIterator> __pstl_transform(
__omp_backend_tag,
_ForwardIterator1 __first1,
_ForwardIterator1 __last1,
_ForwardIterator2 __first2,
_ForwardOutIterator __result,
_BinaryOperation __op) {
- // The interface for the function switched between C++17 and C++20
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
- __has_random_access_iterator_category_or_concept<_ForwardIterator1>::value &&
- __has_random_access_iterator_category_or_concept<_ForwardIterator2>::value &&
+ __is_parallel_execution_policy_v<_ExecutionPolicy> &&
+ __libcpp_is_contiguous_iterator<_ForwardIterator1>::value &&
+ __libcpp_is_contiguous_iterator<_ForwardIterator2>::value &&
__libcpp_is_contiguous_iterator<_ForwardOutIterator>::value) {
- std::__par_backend::__parallel_for_simd_3(__first1, __last1 - __first1, __first2, __result, __op);
+ std::__par_backend::__parallel_for_simd(__first1, __last1 - __first1, __first2, __result, __op);
return __result + (__last1 - __first1);
}
// If it is not safe to offload to the GPU, we rely on the CPU backend.
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h b/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h
index eb0a7ba52d8fdcc..ddc3ba03f8e9b08 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h
@@ -18,6 +18,7 @@
#include <__type_traits/is_arithmetic.h>
#include <__type_traits/is_execution_policy.h>
#include <__type_traits/operation_traits.h>
+#include <optional>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
@@ -56,7 +57,7 @@ template <class _ExecutionPolicy,
class _Tp,
class _BinaryOperation1,
class _BinaryOperation2>
-_LIBCPP_HIDE_FROM_ABI _Tp __pstl_transform_reduce(
+_LIBCPP_HIDE_FROM_ABI optional<_Tp> __pstl_transform_reduce(
__omp_backend_tag,
_ForwardIterator1 __first1,
_ForwardIterator1 __last1,
@@ -66,8 +67,10 @@ _LIBCPP_HIDE_FROM_ABI _Tp __pstl_transform_reduce(
_BinaryOperation2 __transform) {
// The interface for the function switched between C++17 and C++20
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
- __has_random_access_iterator_category_or_concept<_ForwardIterator1>::value &&
- __has_random_access_iterator_category_or_concept<_ForwardIterator2>::value && is_arithmetic_v<_Tp> &&
+ __is_parallel_execution_policy_v<_ExecutionPolicy> &&
+ __libcpp_is_contiguous_iterator<_ForwardIterator1>::value &&
+ __libcpp_is_contiguous_iterator<_ForwardIterator2>::value &&
+ is_arithmetic_v<_Tp> &&
__is_supported_reduction<_BinaryOperation1, _Tp, _Tp>::value) {
return std::__par_backend::__parallel_for_simd_reduction_2(
__first1, __first2, __last1 - __first1, __init, __reduce, __transform);
@@ -81,16 +84,17 @@ _LIBCPP_HIDE_FROM_ABI _Tp __pstl_transform_reduce(
//===----------------------------------------------------------------------===//
template <class _ExecutionPolicy, class _ForwardIterator, class _Tp, class _BinaryOperation, class _UnaryOperation>
-_LIBCPP_HIDE_FROM_ABI _Tp __pstl_transform_reduce(
+_LIBCPP_HIDE_FROM_ABI optional<_Tp> __pstl_transform_reduce(
__omp_backend_tag,
_ForwardIterator __first,
_ForwardIterator __last,
_Tp __init,
_BinaryOperation __reduce,
_UnaryOperation __transform) {
- // The interface for the function switched between C++17 and C++20
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
- __has_random_access_iterator_category_or_concept<_ForwardIterator>::value && is_arithmetic_v<_Tp> &&
+ __is_parallel_execution_policy_v<_ExecutionPolicy> &&
+ __libcpp_is_contiguous_iterator<_ForwardIterator>::value &&
+ is_arithmetic_v<_Tp> &&
__is_supported_reduction<_BinaryOperation, _Tp, _Tp>::value) {
return std::__par_backend::__parallel_for_simd_reduction_1(
__first, __last - __first, __init, __reduce, __transform);
>From d2d9de13b6645150170c4727197641314897e716 Mon Sep 17 00:00:00 2001
From: AntonRydahl <rydahl2610 at gmail.com>
Date: Mon, 16 Oct 2023 08:06:44 -0700
Subject: [PATCH 16/26] Clang formatted files
---
.../__algorithm/pstl_backends/openmp/fill.h | 13 ++++----
.../pstl_backends/openmp/find_if.h | 19 ++++++-----
.../pstl_backends/openmp/for_each.h | 15 +++++----
.../pstl_backends/openmp/omp_offload.h | 32 +++++++++----------
.../pstl_backends/openmp/transform.h | 19 ++++-------
.../pstl_backends/openmp/transform_reduce.h | 6 ++--
6 files changed, 50 insertions(+), 54 deletions(-)
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/fill.h b/libcxx/include/__algorithm/pstl_backends/openmp/fill.h
index 250e514b4d526fd..029b1877e309c16 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/fill.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/fill.h
@@ -29,12 +29,12 @@ namespace __par_backend {
inline namespace __omp_gpu_backend {
template <class _Tp, class _DifferenceType, class _Up>
-_LIBCPP_HIDE_FROM_ABI optional<__empty> __omp_parallel_for_simd_val(
- _Tp* __first, _DifferenceType __n, const _Up& __value) noexcept {
+_LIBCPP_HIDE_FROM_ABI optional<__empty>
+__omp_parallel_for_simd_val(_Tp* __first, _DifferenceType __n, const _Up& __value) noexcept {
__omp_gpu_backend::__omp_map_alloc(__first, __n);
# pragma omp target teams distribute parallel for simd firstprivate(__value)
for (_DifferenceType __i = 0; __i < __n; ++__i)
- *(__first+__i) = __value;
+ *(__first + __i) = __value;
__omp_gpu_backend::__omp_map_from(__first, __n);
return __empty{};
}
@@ -42,11 +42,12 @@ _LIBCPP_HIDE_FROM_ABI optional<__empty> __omp_parallel_for_simd_val(
template <class _ForwardIterator, class _DifferenceType, class _Tp>
_LIBCPP_HIDE_FROM_ABI optional<__empty>
__parallel_for_simd_val(_ForwardIterator __first, _DifferenceType __n, const _Tp& __value) noexcept {
- return __omp_gpu_backend::__omp_parallel_for_simd_val(__omp_gpu_backend::__omp_extract_base_ptr(__first), __n, __value);
+ return __omp_gpu_backend::__omp_parallel_for_simd_val(
+ __omp_gpu_backend::__omp_extract_base_ptr(__first), __n, __value);
}
-}
-}
+} // namespace __omp_gpu_backend
+} // namespace __par_backend
template <class _ExecutionPolicy, class _ForwardIterator, class _Tp>
_LIBCPP_HIDE_FROM_ABI optional<__empty>
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h b/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h
index 94f7c42953c2a4a..19b581a5f72b00a 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h
@@ -27,12 +27,13 @@ namespace __par_backend {
inline namespace __omp_gpu_backend {
template <class _Tp, class _DifferenceType, class _Predicate>
-_LIBCPP_HIDE_FROM_ABI _DifferenceType __omp_parallel_for_min_idx(_Tp* __first, _DifferenceType __n, _Predicate __pred) noexcept {
+_LIBCPP_HIDE_FROM_ABI _DifferenceType
+__omp_parallel_for_min_idx(_Tp* __first, _DifferenceType __n, _Predicate __pred) noexcept {
__omp_gpu_backend::__omp_map_to(__first, __n);
_DifferenceType idx = __n;
-# pragma omp target teams distribute parallel for simd reduction(min:idx)
- for (_DifferenceType __i = 0; __i < __n; ++__i){
- if (__pred(*(__first+__i))) {
+# pragma omp target teams distribute parallel for simd reduction(min : idx)
+ for (_DifferenceType __i = 0; __i < __n; ++__i) {
+ if (__pred(*(__first + __i))) {
idx = (__i < idx) ? __i : idx;
}
}
@@ -43,12 +44,14 @@ _LIBCPP_HIDE_FROM_ABI _DifferenceType __omp_parallel_for_min_idx(_Tp* __first,
// Extracting the underlying pointer
template <class _ForwardIterator, class _DifferenceType, class _Predicate>
-_LIBCPP_HIDE_FROM_ABI optional<_ForwardIterator> __parallel_for_min_idx(_ForwardIterator __first, _DifferenceType __n, _Predicate __pred) noexcept {
- return __first + __omp_gpu_backend::__omp_parallel_for_min_idx(__omp_gpu_backend::__omp_extract_base_ptr(__first), __n, __pred);
+_LIBCPP_HIDE_FROM_ABI optional<_ForwardIterator>
+__parallel_for_min_idx(_ForwardIterator __first, _DifferenceType __n, _Predicate __pred) noexcept {
+ return __first +
+ __omp_gpu_backend::__omp_parallel_for_min_idx(__omp_gpu_backend::__omp_extract_base_ptr(__first), __n, __pred);
}
-}
-}
+} // namespace __omp_gpu_backend
+} // namespace __par_backend
template <class _ExecutionPolicy, class _ForwardIterator, class _Predicate>
_LIBCPP_HIDE_FROM_ABI optional<_ForwardIterator>
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h b/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h
index 444352b4a5e51a8..eea337179b6576c 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h
@@ -14,8 +14,8 @@
#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__config>
#include <__type_traits/is_execution_policy.h>
-#include <optional>
#include <__utility/empty.h>
+#include <optional>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
@@ -29,12 +29,12 @@ namespace __par_backend {
inline namespace __omp_gpu_backend {
template <class _Tp, class _DifferenceType, class _Function>
-_LIBCPP_HIDE_FROM_ABI optional<__empty> __omp_parallel_for_simd(
- _Tp* __first, _DifferenceType __n, _Function __f) noexcept {
+_LIBCPP_HIDE_FROM_ABI optional<__empty>
+__omp_parallel_for_simd(_Tp* __first, _DifferenceType __n, _Function __f) noexcept {
__omp_gpu_backend::__omp_map_to(__first, __n);
# pragma omp target teams distribute parallel for simd
for (_DifferenceType __i = 0; __i < __n; ++__i)
- __f(*(__first+__i));
+ __f(*(__first + __i));
__omp_gpu_backend::__omp_map_from(__first, __n);
return __empty{};
}
@@ -42,12 +42,13 @@ _LIBCPP_HIDE_FROM_ABI optional<__empty> __omp_parallel_for_simd(
// Extracting the underlying pointer
template <class _ForwardIterator, class _DifferenceType, class _Function>
-_LIBCPP_HIDE_FROM_ABI optional<__empty> __parallel_for_simd_1(_ForwardIterator __first, _DifferenceType __n, _Function __f) noexcept {
+_LIBCPP_HIDE_FROM_ABI optional<__empty>
+__parallel_for_simd_1(_ForwardIterator __first, _DifferenceType __n, _Function __f) noexcept {
return __omp_gpu_backend::__omp_parallel_for_simd(__omp_gpu_backend::__omp_extract_base_ptr(__first), __n, __f);
}
-}
-}
+} // namespace __omp_gpu_backend
+} // namespace __par_backend
template <class _ExecutionPolicy, class _ForwardIterator, class _Functor>
_LIBCPP_HIDE_FROM_ABI optional<__empty>
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/omp_offload.h b/libcxx/include/__algorithm/pstl_backends/openmp/omp_offload.h
index 77afb35ee71b4bb..183fdfa5cfa02a5 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/omp_offload.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/omp_offload.h
@@ -9,8 +9,8 @@
#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_OMP_OFFLOAD_H
#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_OMP_OFFLOAD_H
-#include <__assert>
#include <__algorithm/unwrap_iter.h>
+#include <__assert>
#include <__config>
#include <__functional/operations.h>
#include <__iterator/iterator_traits.h>
@@ -19,8 +19,8 @@
#include <__memory/pointer_traits.h>
#include <__type_traits/is_pointer.h>
#include <__type_traits/is_same.h>
-#include <__utility/move.h>
#include <__utility/empty.h>
+#include <__utility/move.h>
#include <cstddef>
#include <optional>
@@ -70,28 +70,28 @@ template <class _Iterator, class _DifferenceType>
_LIBCPP_HIDE_FROM_ABI void
__omp_map_to([[maybe_unused]] const _Iterator p, [[maybe_unused]] const _DifferenceType len) noexcept {
static_assert(__libcpp_is_contiguous_iterator<_Iterator>::value);
-#pragma omp target enter data map(to : p[0 : len])
+# pragma omp target enter data map(to : p[0 : len])
}
template <class _Iterator, class _DifferenceType>
_LIBCPP_HIDE_FROM_ABI void
__omp_map_from([[maybe_unused]] const _Iterator p, [[maybe_unused]] const _DifferenceType len) noexcept {
static_assert(__libcpp_is_contiguous_iterator<_Iterator>::value);
-#pragma omp target exit data map(from : p[0 : len])
+# pragma omp target exit data map(from : p[0 : len])
}
template <class _Iterator, class _DifferenceType>
_LIBCPP_HIDE_FROM_ABI void
__omp_map_alloc([[maybe_unused]] const _Iterator p, [[maybe_unused]] const _DifferenceType len) noexcept {
static_assert(__libcpp_is_contiguous_iterator<_Iterator>::value);
-#pragma omp target enter data map(alloc : p[0 : len])
+# pragma omp target enter data map(alloc : p[0 : len])
}
template <class _Iterator, class _DifferenceType>
_LIBCPP_HIDE_FROM_ABI void
__omp_map_free([[maybe_unused]] const _Iterator p, [[maybe_unused]] const _DifferenceType len) noexcept {
static_assert(__libcpp_is_contiguous_iterator<_Iterator>::value);
-#pragma omp target exit data map(release : p[0 : len])
+# pragma omp target exit data map(release : p[0 : len])
}
//===----------------------------------------------------------------------===//
@@ -112,12 +112,12 @@ __omp_map_free([[maybe_unused]] const _Iterator p, [[maybe_unused]] const _Diffe
_DifferenceType __n, \
_Tp __init, \
std_op<_BinaryOperationType> __reduce, \
- _UnaryOperation __transform) noexcept { \
- __omp_gpu_backend::__omp_map_to(__first, __n); \
-_PSTL_PRAGMA(omp target teams distribute parallel for simd reduction(omp_op:__init)) \
+ _UnaryOperation __transform) noexcept { \
+ __omp_gpu_backend::__omp_map_to(__first, __n); \
+_PSTL_PRAGMA(omp target teams distribute parallel for simd reduction(omp_op:__init)) \
for (_DifferenceType __i = 0; __i < __n; ++__i) \
__init = __reduce(__init, __transform(*(__first + __i))); \
- __omp_gpu_backend::__omp_map_free(__first, __n); \
+ __omp_gpu_backend::__omp_map_free(__first, __n); \
return __init; \
}
@@ -134,14 +134,14 @@ _PSTL_PRAGMA(omp target teams distribute parallel for simd reduction(omp_op:__in
_DifferenceType __n, \
_Tp __init, \
std_op<_BinaryOperationType> __reduce, \
- _UnaryOperation __transform) noexcept { \
- __omp_gpu_backend::__omp_map_to(__first1, __n); \
- __omp_gpu_backend::__omp_map_to(__first2, __n); \
-_PSTL_PRAGMA(omp target teams distribute parallel for simd reduction(omp_op:__init)) \
+ _UnaryOperation __transform) noexcept { \
+ __omp_gpu_backend::__omp_map_to(__first1, __n); \
+ __omp_gpu_backend::__omp_map_to(__first2, __n); \
+_PSTL_PRAGMA(omp target teams distribute parallel for simd reduction(omp_op:__init)) \
for (_DifferenceType __i = 0; __i < __n; ++__i) \
__init = __reduce(__init, __transform(*(__first1 + __i), *(__first2 + __i))); \
- __omp_gpu_backend::__omp_map_free(__first1, __n); \
- __omp_gpu_backend::__omp_map_free(__first2, __n); \
+ __omp_gpu_backend::__omp_map_free(__first1, __n); \
+ __omp_gpu_backend::__omp_map_free(__first2, __n); \
return __init; \
} // namespace __omp_gpu_backend
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/transform.h b/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
index b29a479c17887c7..ba218dddd4be563 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
@@ -33,11 +33,8 @@ inline namespace __omp_gpu_backend {
//===----------------------------------------------------------------------===//
template <class _Tp, class _DifferenceType, class _Up, class _Function>
-_LIBCPP_HIDE_FROM_ABI optional<__empty> __omp_parallel_for_simd(
- _Tp* __first1,
- _DifferenceType __n,
- _Up* __first2,
- _Function __f) noexcept {
+_LIBCPP_HIDE_FROM_ABI optional<__empty>
+__omp_parallel_for_simd(_Tp* __first1, _DifferenceType __n, _Up* __first2, _Function __f) noexcept {
__omp_gpu_backend::__omp_map_alloc(__first2, __n);
__omp_gpu_backend::__omp_map_to(__first1, __n);
# pragma omp target teams distribute parallel for simd
@@ -65,12 +62,8 @@ __parallel_for_simd(_Iterator1 __first1, _DifferenceType __n, _Iterator2 __first
//===----------------------------------------------------------------------===//
template <class _Tp, class _DifferenceType, class _Up, class _Vp, class _Function>
-_LIBCPP_HIDE_FROM_ABI optional<__empty> __omp_parallel_for_simd(
- _Tp* __first1,
- _DifferenceType __n,
- _Up* __first2,
- _Vp* __first3,
- _Function __f) noexcept {
+_LIBCPP_HIDE_FROM_ABI optional<__empty>
+__omp_parallel_for_simd(_Tp* __first1, _DifferenceType __n, _Up* __first2, _Vp* __first3, _Function __f) noexcept {
__omp_gpu_backend::__omp_map_to(__first1, __n);
__omp_gpu_backend::__omp_map_to(__first2, __n);
__omp_gpu_backend::__omp_map_alloc(__first3, __n);
@@ -96,8 +89,8 @@ _LIBCPP_HIDE_FROM_ABI optional<__empty> __parallel_for_simd(
__f);
}
-}
-}
+} // namespace __omp_gpu_backend
+} // namespace __par_backend
template <class _ExecutionPolicy, class _ForwardIterator, class _ForwardOutIterator, class _UnaryOperation>
_LIBCPP_HIDE_FROM_ABI optional<_ForwardOutIterator> __pstl_transform(
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h b/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h
index ddc3ba03f8e9b08..1427184d04d0c83 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h
@@ -69,8 +69,7 @@ _LIBCPP_HIDE_FROM_ABI optional<_Tp> __pstl_transform_reduce(
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__is_parallel_execution_policy_v<_ExecutionPolicy> &&
__libcpp_is_contiguous_iterator<_ForwardIterator1>::value &&
- __libcpp_is_contiguous_iterator<_ForwardIterator2>::value &&
- is_arithmetic_v<_Tp> &&
+ __libcpp_is_contiguous_iterator<_ForwardIterator2>::value && is_arithmetic_v<_Tp> &&
__is_supported_reduction<_BinaryOperation1, _Tp, _Tp>::value) {
return std::__par_backend::__parallel_for_simd_reduction_2(
__first1, __first2, __last1 - __first1, __init, __reduce, __transform);
@@ -93,8 +92,7 @@ _LIBCPP_HIDE_FROM_ABI optional<_Tp> __pstl_transform_reduce(
_UnaryOperation __transform) {
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__is_parallel_execution_policy_v<_ExecutionPolicy> &&
- __libcpp_is_contiguous_iterator<_ForwardIterator>::value &&
- is_arithmetic_v<_Tp> &&
+ __libcpp_is_contiguous_iterator<_ForwardIterator>::value && is_arithmetic_v<_Tp> &&
__is_supported_reduction<_BinaryOperation, _Tp, _Tp>::value) {
return std::__par_backend::__parallel_for_simd_reduction_1(
__first, __last - __first, __init, __reduce, __transform);
>From c485b2b00a4ccfd52a24a11f27028f55980cb984 Mon Sep 17 00:00:00 2001
From: AntonRydahl <rydahl2610 at gmail.com>
Date: Thu, 19 Oct 2023 11:35:54 -0700
Subject: [PATCH 17/26] Fixing issued discussed during code review on the 16th
of October
- Updated CMake logic
- Made `fill` call `transform` with a lambda returning a constant.
- Used `__rewrap_iter` and `__unwrap_iter`.
---
libcxx/CMakeLists.txt | 13 +-
.../pstl_backends/openmp/backend.h | 8 +
.../__algorithm/pstl_backends/openmp/fill.h | 31 +---
.../pstl_backends/openmp/find_if.h | 27 +---
.../pstl_backends/openmp/for_each.h | 29 +---
.../pstl_backends/openmp/omp_offload.h | 144 ++----------------
.../pstl_backends/openmp/transform.h | 67 +++-----
.../pstl_backends/openmp/transform_reduce.h | 130 ++++++++++++----
8 files changed, 163 insertions(+), 286 deletions(-)
diff --git a/libcxx/CMakeLists.txt b/libcxx/CMakeLists.txt
index 24dd562035d24ed..0fdeab59e89f767 100644
--- a/libcxx/CMakeLists.txt
+++ b/libcxx/CMakeLists.txt
@@ -295,15 +295,14 @@ option(LIBCXX_HAS_EXTERNAL_THREAD_API
"Build libc++ with an externalized threading API.
This option may only be set to ON when LIBCXX_ENABLE_THREADS=ON." OFF)
-set(LIBCXX_PSTL_BACKEND "openmp" CACHE INTERNAL "Which PSTL backend to use")
-if (LIBCXX_PSTL_BACKEND STREQUAL "")
- if (LIBCXX_ENABLE_THREADS)
- set(LIBCXX_PSTL_BACKEND "std-thread")
- else()
- set(LIBCXX_PSTL_BACKEND "serial")
- endif()
+if (LIBCXX_ENABLE_THREADS)
+ set(LIBCXX_PSTL_BACKEND_DEFAULT "std-thread")
+else()
+ set(LIBCXX_PSTL_BACKEND_DEFAULT "serial")
endif()
+set(LIBCXX_PSTL_BACKEND "${LIBCXX_PSTL_BACKEND_DEFAULT}" CACHE STRING "Select the PSTL backend to use. Valid values are serial, std-thread, libdispatch, openmp. Default: ${LIBCXX_PSTL_BACKEND_DEFAULT}")
+
# Misc options ----------------------------------------------------------------
# FIXME: Turn -pedantic back ON. It is currently off because it warns
# about #include_next which is used everywhere.
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/backend.h b/libcxx/include/__algorithm/pstl_backends/openmp/backend.h
index e4e6136082a3427..9396f91b1a755f2 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/backend.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/backend.h
@@ -20,6 +20,14 @@
#if _LIBCPP_STD_VER >= 17
+#if defined(_LIBCPP_PSTL_BACKEND_OPENMP)
+# if !defined(_OPENMP)
+//# warning "PSTL is configured to use the OpenMP backend, but OpenMP is not enabled. Did you compile with -fopenmp?"
+# elif (defined(_OPENMP) && _OPENMP < 201511)
+//# warning "OpenMP target offloading has been supported since OpenMP version 4.5 (201511). Please use a more recent version of OpenMP."
+# endif
+#endif
+
_LIBCPP_BEGIN_NAMESPACE_STD
struct __omp_backend_tag {};
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/fill.h b/libcxx/include/__algorithm/pstl_backends/openmp/fill.h
index 029b1877e309c16..e8101233e342a3e 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/fill.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/fill.h
@@ -13,7 +13,9 @@
#include <__algorithm/pstl_backends/cpu_backends/backend.h>
#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__config>
+#include <__iterator/wrap_iter.h>
#include <__type_traits/is_execution_policy.h>
+#include <__type_traits/remove_pointer.h>
#include <__utility/empty.h>
#include <optional>
@@ -25,30 +27,6 @@
_LIBCPP_BEGIN_NAMESPACE_STD
-namespace __par_backend {
-inline namespace __omp_gpu_backend {
-
-template <class _Tp, class _DifferenceType, class _Up>
-_LIBCPP_HIDE_FROM_ABI optional<__empty>
-__omp_parallel_for_simd_val(_Tp* __first, _DifferenceType __n, const _Up& __value) noexcept {
- __omp_gpu_backend::__omp_map_alloc(__first, __n);
-# pragma omp target teams distribute parallel for simd firstprivate(__value)
- for (_DifferenceType __i = 0; __i < __n; ++__i)
- *(__first + __i) = __value;
- __omp_gpu_backend::__omp_map_from(__first, __n);
- return __empty{};
-}
-
-template <class _ForwardIterator, class _DifferenceType, class _Tp>
-_LIBCPP_HIDE_FROM_ABI optional<__empty>
-__parallel_for_simd_val(_ForwardIterator __first, _DifferenceType __n, const _Tp& __value) noexcept {
- return __omp_gpu_backend::__omp_parallel_for_simd_val(
- __omp_gpu_backend::__omp_extract_base_ptr(__first), __n, __value);
-}
-
-} // namespace __omp_gpu_backend
-} // namespace __par_backend
-
template <class _ExecutionPolicy, class _ForwardIterator, class _Tp>
_LIBCPP_HIDE_FROM_ABI optional<__empty>
__pstl_fill(__omp_backend_tag, _ForwardIterator __first, _ForwardIterator __last, const _Tp& __value) {
@@ -58,7 +36,10 @@ __pstl_fill(__omp_backend_tag, _ForwardIterator __first, _ForwardIterator __last
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__is_parallel_execution_policy_v<_ExecutionPolicy> &&
__libcpp_is_contiguous_iterator<_ForwardIterator>::value) {
- return std::__par_backend::__parallel_for_simd_val(__first, __last - __first, __value);
+ std::__rewrap_iter(__first, __par_backend::__omp_for_each(std::__unwrap_iter(__first), __last - __first, [&](std::remove_pointer_t<decltype(std::__unwrap_iter(__first))>& e) {
+ e = __value;
+ }));
+ return __empty{};
}
// Otherwise, we execute fill on the CPU instead
else {
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h b/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h
index 19b581a5f72b00a..f07965885c9c68c 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h
@@ -13,6 +13,7 @@
#include <__algorithm/pstl_backends/cpu_backends/backend.h>
#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__config>
+#include <__iterator/wrap_iter.h>
#include <optional>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
@@ -23,13 +24,9 @@
_LIBCPP_BEGIN_NAMESPACE_STD
-namespace __par_backend {
-inline namespace __omp_gpu_backend {
-
template <class _Tp, class _DifferenceType, class _Predicate>
-_LIBCPP_HIDE_FROM_ABI _DifferenceType
-__omp_parallel_for_min_idx(_Tp* __first, _DifferenceType __n, _Predicate __pred) noexcept {
- __omp_gpu_backend::__omp_map_to(__first, __n);
+_LIBCPP_HIDE_FROM_ABI _Tp* __omp_find_if(_Tp* __first, _DifferenceType __n, _Predicate __pred) noexcept {
+ __par_backend::__omp_map_to(__first, __n);
_DifferenceType idx = __n;
# pragma omp target teams distribute parallel for simd reduction(min : idx)
for (_DifferenceType __i = 0; __i < __n; ++__i) {
@@ -37,29 +34,17 @@ __omp_parallel_for_min_idx(_Tp* __first, _DifferenceType __n, _Predicate __pred)
idx = (__i < idx) ? __i : idx;
}
}
- __omp_gpu_backend::__omp_map_free(__first, __n);
- return idx;
-}
-
-// Extracting the underlying pointer
-
-template <class _ForwardIterator, class _DifferenceType, class _Predicate>
-_LIBCPP_HIDE_FROM_ABI optional<_ForwardIterator>
-__parallel_for_min_idx(_ForwardIterator __first, _DifferenceType __n, _Predicate __pred) noexcept {
- return __first +
- __omp_gpu_backend::__omp_parallel_for_min_idx(__omp_gpu_backend::__omp_extract_base_ptr(__first), __n, __pred);
+ __par_backend::__omp_map_free(__first, __n);
+ return __first + idx;
}
-} // namespace __omp_gpu_backend
-} // namespace __par_backend
-
template <class _ExecutionPolicy, class _ForwardIterator, class _Predicate>
_LIBCPP_HIDE_FROM_ABI optional<_ForwardIterator>
__pstl_find_if(__omp_backend_tag, _ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) {
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__is_parallel_execution_policy_v<_ExecutionPolicy> &&
__libcpp_is_contiguous_iterator<_ForwardIterator>::value) {
- return __par_backend::__parallel_for_min_idx(__first, __last - __first, __pred);
+ return std::__rewrap_iter(__first, std::__omp_find_if(std::__unwrap_iter(__first), __last - __first, __pred));
} else {
return std::__pstl_find_if<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __pred);
}
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h b/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h
index eea337179b6576c..eb8caf23971cb33 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h
@@ -13,6 +13,7 @@
#include <__algorithm/pstl_backends/cpu_backends/backend.h>
#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__config>
+#include <__iterator/wrap_iter.h>
#include <__type_traits/is_execution_policy.h>
#include <__utility/empty.h>
#include <optional>
@@ -25,31 +26,6 @@
_LIBCPP_BEGIN_NAMESPACE_STD
-namespace __par_backend {
-inline namespace __omp_gpu_backend {
-
-template <class _Tp, class _DifferenceType, class _Function>
-_LIBCPP_HIDE_FROM_ABI optional<__empty>
-__omp_parallel_for_simd(_Tp* __first, _DifferenceType __n, _Function __f) noexcept {
- __omp_gpu_backend::__omp_map_to(__first, __n);
-# pragma omp target teams distribute parallel for simd
- for (_DifferenceType __i = 0; __i < __n; ++__i)
- __f(*(__first + __i));
- __omp_gpu_backend::__omp_map_from(__first, __n);
- return __empty{};
-}
-
-// Extracting the underlying pointer
-
-template <class _ForwardIterator, class _DifferenceType, class _Function>
-_LIBCPP_HIDE_FROM_ABI optional<__empty>
-__parallel_for_simd_1(_ForwardIterator __first, _DifferenceType __n, _Function __f) noexcept {
- return __omp_gpu_backend::__omp_parallel_for_simd(__omp_gpu_backend::__omp_extract_base_ptr(__first), __n, __f);
-}
-
-} // namespace __omp_gpu_backend
-} // namespace __par_backend
-
template <class _ExecutionPolicy, class _ForwardIterator, class _Functor>
_LIBCPP_HIDE_FROM_ABI optional<__empty>
__pstl_for_each(__omp_backend_tag, _ForwardIterator __first, _ForwardIterator __last, _Functor __func) {
@@ -59,7 +35,8 @@ __pstl_for_each(__omp_backend_tag, _ForwardIterator __first, _ForwardIterator __
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__libcpp_is_contiguous_iterator<_ForwardIterator>::value &&
__libcpp_is_contiguous_iterator<_ForwardIterator>::value) {
- return std::__par_backend::__parallel_for_simd_1(__first, __last - __first, __func);
+ __par_backend::__omp_for_each(std::__unwrap_iter(__first), __last - __first, __func);
+ return __empty{};
}
// Else we fall back to the serial backend
else {
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/omp_offload.h b/libcxx/include/__algorithm/pstl_backends/openmp/omp_offload.h
index 183fdfa5cfa02a5..2e44af3c9a761f5 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/omp_offload.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/omp_offload.h
@@ -22,7 +22,6 @@
#include <__utility/empty.h>
#include <__utility/move.h>
#include <cstddef>
-#include <optional>
// is_same
@@ -43,27 +42,9 @@ namespace __par_backend {
inline namespace __omp_gpu_backend {
//===----------------------------------------------------------------------===//
-// Functions for eaxtracting the pase pointers
-//===----------------------------------------------------------------------===//
-
-// In the general case we do not need to extract it. This is for instance the
-// case for pointers.
-template <typename _Tp>
-_LIBCPP_HIDE_FROM_ABI inline auto __omp_extract_base_ptr(_Tp p) noexcept {
- return std::__unwrap_iter(p);
-}
-
-// For vectors and arrays, etc, we need to extract the underlying base pointer.
-template <typename _Tp>
-_LIBCPP_HIDE_FROM_ABI inline _Tp __omp_extract_base_ptr(std::__wrap_iter<_Tp> w) noexcept {
- std::pointer_traits<std::__wrap_iter<_Tp>> PT;
- return PT.to_address(w);
-}
-
-//===----------------------------------------------------------------------===//
-// The following four functions differentiates between contiguous iterators and
-// non-contiguous iterators. That allows to use the same implementations for
-// reference and value iterators
+// The following four functions can be used to map contiguous array sections to
+// and from the device. For now, they are simple overlays of the OpenMP pragmas,
+// but they should be updated wen adding support for other iterator types.
//===----------------------------------------------------------------------===//
template <class _Iterator, class _DifferenceType>
@@ -95,117 +76,18 @@ __omp_map_free([[maybe_unused]] const _Iterator p, [[maybe_unused]] const _Diffe
}
//===----------------------------------------------------------------------===//
-// Templates for reductions
+// The OpenMP implementation of for_each is shared between for_each and fill
//===----------------------------------------------------------------------===//
-// In the two following function templates, we map the pointer to the device in
-// different ways depending on if they are contiguou or not.
-
-# define __PSTL_OMP_SIMD_1_REDUCTION(omp_op, std_op) \
- template <class _Iterator, \
- class _DifferenceType, \
- typename _Tp, \
- typename _BinaryOperationType, \
- typename _UnaryOperation> \
- _LIBCPP_HIDE_FROM_ABI _Tp __omp_parallel_for_simd_reduction_1( \
- _Iterator __first, \
- _DifferenceType __n, \
- _Tp __init, \
- std_op<_BinaryOperationType> __reduce, \
- _UnaryOperation __transform) noexcept { \
- __omp_gpu_backend::__omp_map_to(__first, __n); \
-_PSTL_PRAGMA(omp target teams distribute parallel for simd reduction(omp_op:__init)) \
- for (_DifferenceType __i = 0; __i < __n; ++__i) \
- __init = __reduce(__init, __transform(*(__first + __i))); \
- __omp_gpu_backend::__omp_map_free(__first, __n); \
- return __init; \
- }
-
-# define __PSTL_OMP_SIMD_2_REDUCTION(omp_op, std_op) \
- template <class _Iterator1, \
- class _Iterator2, \
- class _DifferenceType, \
- typename _Tp, \
- typename _BinaryOperationType, \
- typename _UnaryOperation > \
- _LIBCPP_HIDE_FROM_ABI _Tp __omp_parallel_for_simd_reduction_2( \
- _Iterator1 __first1, \
- _Iterator2 __first2, \
- _DifferenceType __n, \
- _Tp __init, \
- std_op<_BinaryOperationType> __reduce, \
- _UnaryOperation __transform) noexcept { \
- __omp_gpu_backend::__omp_map_to(__first1, __n); \
- __omp_gpu_backend::__omp_map_to(__first2, __n); \
-_PSTL_PRAGMA(omp target teams distribute parallel for simd reduction(omp_op:__init)) \
- for (_DifferenceType __i = 0; __i < __n; ++__i) \
- __init = __reduce(__init, __transform(*(__first1 + __i), *(__first2 + __i))); \
- __omp_gpu_backend::__omp_map_free(__first1, __n); \
- __omp_gpu_backend::__omp_map_free(__first2, __n); \
- return __init; \
- } // namespace __omp_gpu_backend
-
-# define __PSTL_OMP_SIMD_REDUCTION(omp_op, std_op) \
- __PSTL_OMP_SIMD_1_REDUCTION(omp_op, std_op) \
- __PSTL_OMP_SIMD_2_REDUCTION(omp_op, std_op)
-
-// Addition
-__PSTL_OMP_SIMD_REDUCTION(+, std::plus)
-
-// Subtraction
-__PSTL_OMP_SIMD_REDUCTION(-, std::minus)
-
-// Multiplication
-__PSTL_OMP_SIMD_REDUCTION(*, std::multiplies)
-
-// Logical and
-__PSTL_OMP_SIMD_REDUCTION(&&, std::logical_and)
-
-// Logical or
-__PSTL_OMP_SIMD_REDUCTION(||, std::logical_or)
-
-// Bitwise and
-__PSTL_OMP_SIMD_REDUCTION(&, std::bit_and)
-
-// Bitwise or
-__PSTL_OMP_SIMD_REDUCTION(|, std::bit_or)
-
-// Bitwise xor
-__PSTL_OMP_SIMD_REDUCTION(^, std::bit_xor)
-
-// Extracting the underlying pointers
-
-template <class _Iterator, class _DifferenceType, typename _Tp, typename _BinaryOperation, typename _UnaryOperation >
-_LIBCPP_HIDE_FROM_ABI _Tp __parallel_for_simd_reduction_1(
- _Iterator __first,
- _DifferenceType __n,
- _Tp __init,
- _BinaryOperation __reduce,
- _UnaryOperation __transform) noexcept {
- return __omp_gpu_backend::__omp_parallel_for_simd_reduction_1(
- __omp_gpu_backend::__omp_extract_base_ptr(__first), __n, __init, __reduce, __transform);
-}
-
-template <class _Iterator1,
- class _Iterator2,
- class _DifferenceType,
- typename _Tp,
- typename _BinaryOperation,
- typename _UnaryOperation >
-_LIBCPP_HIDE_FROM_ABI _Tp __parallel_for_simd_reduction_2(
- _Iterator1 __first1,
- _Iterator2 __first2,
- _DifferenceType __n,
- _Tp __init,
- _BinaryOperation __reduce,
- _UnaryOperation __transform) noexcept {
- return __omp_gpu_backend::__omp_parallel_for_simd_reduction_2(
- __omp_gpu_backend::__omp_extract_base_ptr(__first1),
- __omp_gpu_backend::__omp_extract_base_ptr(__first2),
- __n,
- __init,
- __reduce,
- __transform);
+template <class _Tp, class _DifferenceType, class _Function>
+_LIBCPP_HIDE_FROM_ABI _Tp*
+__omp_for_each(_Tp* __first, _DifferenceType __n, _Function __f) noexcept {
+ __par_backend::__omp_map_to(__first, __n);
+# pragma omp target teams distribute parallel for simd
+ for (_DifferenceType __i = 0; __i < __n; ++__i)
+ __f(*(__first + __i));
+ __par_backend::__omp_map_from(__first, __n);
+ return __first + __n;
}
} // namespace __omp_gpu_backend
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/transform.h b/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
index ba218dddd4be563..f7e52d7933b6c40 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
@@ -14,6 +14,7 @@
#include <__algorithm/transform.h>
#include <__config>
#include <__iterator/concepts.h>
+#include <__iterator/wrap_iter.h>
#include <__type_traits/is_execution_policy.h>
#include <optional>
@@ -25,73 +26,39 @@
_LIBCPP_BEGIN_NAMESPACE_STD
-namespace __par_backend {
-inline namespace __omp_gpu_backend {
-
//===----------------------------------------------------------------------===//
-// Templates for two iterators
+// OpenMP implementations of transform for one and two input iterators and one
+// output iterator
//===----------------------------------------------------------------------===//
template <class _Tp, class _DifferenceType, class _Up, class _Function>
_LIBCPP_HIDE_FROM_ABI optional<__empty>
-__omp_parallel_for_simd(_Tp* __first1, _DifferenceType __n, _Up* __first2, _Function __f) noexcept {
- __omp_gpu_backend::__omp_map_alloc(__first2, __n);
- __omp_gpu_backend::__omp_map_to(__first1, __n);
+__omp_transform(_Tp* __first1, _DifferenceType __n, _Up* __first2, _Function __f) noexcept {
+ __par_backend::__omp_map_alloc(__first2, __n);
+ __par_backend::__omp_map_to(__first1, __n);
# pragma omp target teams distribute parallel for simd
for (_DifferenceType __i = 0; __i < __n; ++__i)
*(__first2 + __i) = __f(*(__first1 + __i));
- __omp_gpu_backend::__omp_map_from(__first2, __n);
- __omp_gpu_backend::__omp_map_free(__first1, __n);
+ __par_backend::__omp_map_from(__first2, __n);
+ __par_backend::__omp_map_free(__first1, __n);
return __empty{};
}
-// Extracting the underlying pointer
-
-template <class _Iterator1, class _DifferenceType, class _Iterator2, class _Function>
-_LIBCPP_HIDE_FROM_ABI optional<__empty>
-__parallel_for_simd(_Iterator1 __first1, _DifferenceType __n, _Iterator2 __first2, _Function __f) noexcept {
- return __omp_gpu_backend::__omp_parallel_for_simd(
- __omp_gpu_backend::__omp_extract_base_ptr(__first1),
- __n,
- __omp_gpu_backend::__omp_extract_base_ptr(__first2),
- __f);
-}
-
-//===----------------------------------------------------------------------===//
-// Templates for three iterator
-//===----------------------------------------------------------------------===//
-
template <class _Tp, class _DifferenceType, class _Up, class _Vp, class _Function>
_LIBCPP_HIDE_FROM_ABI optional<__empty>
-__omp_parallel_for_simd(_Tp* __first1, _DifferenceType __n, _Up* __first2, _Vp* __first3, _Function __f) noexcept {
- __omp_gpu_backend::__omp_map_to(__first1, __n);
- __omp_gpu_backend::__omp_map_to(__first2, __n);
- __omp_gpu_backend::__omp_map_alloc(__first3, __n);
+__omp_transform(_Tp* __first1, _DifferenceType __n, _Up* __first2, _Vp* __first3, _Function __f) noexcept {
+ __par_backend::__omp_map_to(__first1, __n);
+ __par_backend::__omp_map_to(__first2, __n);
+ __par_backend::__omp_map_alloc(__first3, __n);
# pragma omp target teams distribute parallel for simd
for (_DifferenceType __i = 0; __i < __n; ++__i)
*(__first3 + __i) = __f(*(__first1 + __i), *(__first2 + __i));
- __omp_gpu_backend::__omp_map_free(__first1, __n);
- __omp_gpu_backend::__omp_map_free(__first2, __n);
- __omp_gpu_backend::__omp_map_from(__first3, __n);
+ __par_backend::__omp_map_free(__first1, __n);
+ __par_backend::__omp_map_free(__first2, __n);
+ __par_backend::__omp_map_from(__first3, __n);
return __empty{};
}
-// Extracting the underlying pointer
-
-template <class _Iterator1, class _DifferenceType, class _Iterator2, class _Iterator3, class _Function>
-_LIBCPP_HIDE_FROM_ABI optional<__empty> __parallel_for_simd(
- _Iterator1 __first1, _DifferenceType __n, _Iterator2 __first2, _Iterator3 __first3, _Function __f) noexcept {
- return __omp_gpu_backend::__omp_parallel_for_simd(
- __omp_gpu_backend::__omp_extract_base_ptr(__first1),
- __n,
- __omp_gpu_backend::__omp_extract_base_ptr(__first2),
- __omp_gpu_backend::__omp_extract_base_ptr(__first3),
- __f);
-}
-
-} // namespace __omp_gpu_backend
-} // namespace __par_backend
-
template <class _ExecutionPolicy, class _ForwardIterator, class _ForwardOutIterator, class _UnaryOperation>
_LIBCPP_HIDE_FROM_ABI optional<_ForwardOutIterator> __pstl_transform(
__omp_backend_tag,
@@ -103,7 +70,7 @@ _LIBCPP_HIDE_FROM_ABI optional<_ForwardOutIterator> __pstl_transform(
__is_parallel_execution_policy_v<_ExecutionPolicy> &&
__libcpp_is_contiguous_iterator<_ForwardIterator>::value &&
__libcpp_is_contiguous_iterator<_ForwardOutIterator>::value) {
- std::__par_backend::__parallel_for_simd(__first, __last - __first, __result, __op);
+ std::__omp_transform(std::__unwrap_iter(__first), __last - __first, std::__unwrap_iter(__result), __op);
return __result + (__last - __first);
}
// If it is not safe to offload to the GPU, we rely on the CPU backend.
@@ -128,7 +95,7 @@ _LIBCPP_HIDE_FROM_ABI optional<_ForwardOutIterator> __pstl_transform(
__libcpp_is_contiguous_iterator<_ForwardIterator1>::value &&
__libcpp_is_contiguous_iterator<_ForwardIterator2>::value &&
__libcpp_is_contiguous_iterator<_ForwardOutIterator>::value) {
- std::__par_backend::__parallel_for_simd(__first1, __last1 - __first1, __first2, __result, __op);
+ std::__omp_transform(std::__unwrap_iter(__first1), __last1 - __first1, std::__unwrap_iter(__first2), std::__unwrap_iter(__result), __op);
return __result + (__last1 - __first1);
}
// If it is not safe to offload to the GPU, we rely on the CPU backend.
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h b/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h
index 1427184d04d0c83..3798e1cb3f3fac1 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h
@@ -13,6 +13,7 @@
#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__config>
#include <__iterator/concepts.h>
+#include <__iterator/wrap_iter.h>
#include <__numeric/transform_reduce.h>
#include <__type_traits/integral_constant.h>
#include <__type_traits/is_arithmetic.h>
@@ -28,6 +29,87 @@
_LIBCPP_BEGIN_NAMESPACE_STD
+//===----------------------------------------------------------------------===//
+// Templates for predefined reductions
+//===----------------------------------------------------------------------===//
+
+# define __PSTL_OMP_SIMD_1_REDUCTION(omp_op, std_op) \
+ template <class _Iterator, \
+ class _DifferenceType, \
+ typename _Tp, \
+ typename _BinaryOperationType, \
+ typename _UnaryOperation> \
+ _LIBCPP_HIDE_FROM_ABI _Tp __omp_transform_reduce( \
+ _Iterator __first, \
+ _DifferenceType __n, \
+ _Tp __init, \
+ std_op<_BinaryOperationType> __reduce, \
+ _UnaryOperation __transform) noexcept { \
+ __par_backend::__omp_map_to(__first, __n); \
+_PSTL_PRAGMA(omp target teams distribute parallel for simd reduction(omp_op:__init)) \
+ for (_DifferenceType __i = 0; __i < __n; ++__i) \
+ __init = __reduce(__init, __transform(*(__first + __i))); \
+ __par_backend::__omp_map_free(__first, __n); \
+ return __init; \
+ }
+
+# define __PSTL_OMP_SIMD_2_REDUCTION(omp_op, std_op) \
+ template <class _Iterator1, \
+ class _Iterator2, \
+ class _DifferenceType, \
+ typename _Tp, \
+ typename _BinaryOperationType, \
+ typename _UnaryOperation > \
+ _LIBCPP_HIDE_FROM_ABI _Tp __omp_transform_reduce( \
+ _Iterator1 __first1, \
+ _Iterator2 __first2, \
+ _DifferenceType __n, \
+ _Tp __init, \
+ std_op<_BinaryOperationType> __reduce, \
+ _UnaryOperation __transform) noexcept { \
+ __par_backend::__omp_map_to(__first1, __n); \
+ __par_backend::__omp_map_to(__first2, __n); \
+_PSTL_PRAGMA(omp target teams distribute parallel for simd reduction(omp_op:__init)) \
+ for (_DifferenceType __i = 0; __i < __n; ++__i) \
+ __init = __reduce(__init, __transform(*(__first1 + __i), *(__first2 + __i))); \
+ __par_backend::__omp_map_free(__first1, __n); \
+ __par_backend::__omp_map_free(__first2, __n); \
+ return __init; \
+ }
+
+# define __PSTL_OMP_SIMD_REDUCTION(omp_op, std_op) \
+ __PSTL_OMP_SIMD_1_REDUCTION(omp_op, std_op) \
+ __PSTL_OMP_SIMD_2_REDUCTION(omp_op, std_op)
+
+// Addition
+__PSTL_OMP_SIMD_REDUCTION(+, std::plus)
+
+// Subtraction
+__PSTL_OMP_SIMD_REDUCTION(-, std::minus)
+
+// Multiplication
+__PSTL_OMP_SIMD_REDUCTION(*, std::multiplies)
+
+// Logical and
+__PSTL_OMP_SIMD_REDUCTION(&&, std::logical_and)
+
+// Logical or
+__PSTL_OMP_SIMD_REDUCTION(||, std::logical_or)
+
+// Bitwise and
+__PSTL_OMP_SIMD_REDUCTION(&, std::bit_and)
+
+// Bitwise or
+__PSTL_OMP_SIMD_REDUCTION(|, std::bit_or)
+
+// Bitwise xor
+__PSTL_OMP_SIMD_REDUCTION(^, std::bit_xor)
+
+//===----------------------------------------------------------------------===//
+// The following struct is used to determine whether a reduction is supported by
+// the OpenMP backend.
+//===----------------------------------------------------------------------===//
+
template <class _T1, class _T2, class _T3>
struct __is_supported_reduction : std::false_type {};
@@ -48,9 +130,28 @@ __PSTL_IS_SUPPORTED_REDUCTION(bit_or)
__PSTL_IS_SUPPORTED_REDUCTION(bit_xor)
//===----------------------------------------------------------------------===//
-// Two input iterators
+// Implementation of PSTL transform_reduce for one and two input iterators
//===----------------------------------------------------------------------===//
+template <class _ExecutionPolicy, class _ForwardIterator, class _Tp, class _BinaryOperation, class _UnaryOperation>
+_LIBCPP_HIDE_FROM_ABI optional<_Tp> __pstl_transform_reduce(
+ __omp_backend_tag,
+ _ForwardIterator __first,
+ _ForwardIterator __last,
+ _Tp __init,
+ _BinaryOperation __reduce,
+ _UnaryOperation __transform) {
+ if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
+ __is_parallel_execution_policy_v<_ExecutionPolicy> &&
+ __libcpp_is_contiguous_iterator<_ForwardIterator>::value && is_arithmetic_v<_Tp> &&
+ __is_supported_reduction<_BinaryOperation, _Tp, _Tp>::value) {
+ return std::__omp_transform_reduce(
+ std::__unwrap_iter(__first), __last - __first, __init, __reduce, __transform);
+ }
+ return std::__pstl_transform_reduce<_ExecutionPolicy>(
+ __cpu_backend_tag{}, __first, __last, std::move(__init), __reduce, __transform);
+}
+
template <class _ExecutionPolicy,
class _ForwardIterator1,
class _ForwardIterator2,
@@ -71,36 +172,13 @@ _LIBCPP_HIDE_FROM_ABI optional<_Tp> __pstl_transform_reduce(
__libcpp_is_contiguous_iterator<_ForwardIterator1>::value &&
__libcpp_is_contiguous_iterator<_ForwardIterator2>::value && is_arithmetic_v<_Tp> &&
__is_supported_reduction<_BinaryOperation1, _Tp, _Tp>::value) {
- return std::__par_backend::__parallel_for_simd_reduction_2(
- __first1, __first2, __last1 - __first1, __init, __reduce, __transform);
+ return std::__omp_transform_reduce(
+ std::__unwrap_iter(__first1), std::__unwrap_iter(__first2), __last1 - __first1, __init, __reduce, __transform);
}
return std::__pstl_transform_reduce<_ExecutionPolicy>(
__cpu_backend_tag{}, __first1, __last1, __first2, std::move(__init), __reduce, __transform);
}
-//===----------------------------------------------------------------------===//
-// One input iterator
-//===----------------------------------------------------------------------===//
-
-template <class _ExecutionPolicy, class _ForwardIterator, class _Tp, class _BinaryOperation, class _UnaryOperation>
-_LIBCPP_HIDE_FROM_ABI optional<_Tp> __pstl_transform_reduce(
- __omp_backend_tag,
- _ForwardIterator __first,
- _ForwardIterator __last,
- _Tp __init,
- _BinaryOperation __reduce,
- _UnaryOperation __transform) {
- if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
- __is_parallel_execution_policy_v<_ExecutionPolicy> &&
- __libcpp_is_contiguous_iterator<_ForwardIterator>::value && is_arithmetic_v<_Tp> &&
- __is_supported_reduction<_BinaryOperation, _Tp, _Tp>::value) {
- return std::__par_backend::__parallel_for_simd_reduction_1(
- __first, __last - __first, __init, __reduce, __transform);
- }
- return std::__pstl_transform_reduce<_ExecutionPolicy>(
- __cpu_backend_tag{}, __first, __last, std::move(__init), __reduce, __transform);
-}
-
_LIBCPP_END_NAMESPACE_STD
#endif // !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
>From d7eff87e04ddaa4e42c6bf3eee0e2ec7b8b77d1e Mon Sep 17 00:00:00 2001
From: AntonRydahl <rydahl2610 at gmail.com>
Date: Thu, 19 Oct 2023 17:55:42 -0700
Subject: [PATCH 18/26] Added OpenMP offloading documentation to libcxx
---
libcxx/docs/BuildingLibcxx.rst | 11 ++++
libcxx/docs/UsingLibcxx.rst | 107 +++++++++++++++++++++++++++++++++
2 files changed, 118 insertions(+)
diff --git a/libcxx/docs/BuildingLibcxx.rst b/libcxx/docs/BuildingLibcxx.rst
index 2cee97c03ced089..cbd6183cbd35660 100644
--- a/libcxx/docs/BuildingLibcxx.rst
+++ b/libcxx/docs/BuildingLibcxx.rst
@@ -408,6 +408,17 @@ libc++ Feature Options
Use the specified GCC toolchain and standard library when building the native
stdlib benchmark tests.
+.. option:: LIBCXX_PSTL_BACKEND:STRING
+
+ **Default**:: ``"serial"``
+
+ **Values**:: ``serial``, ``std-thread``, ``libdispatch``, ``openmp``
+
+ Select the desired backend for C++ parallel algorithms. All four options can
+ target multi-core CPU architectures, and ``openmp`` can additionally target
+ GPU architectures. The ``openmp`` backend requires OpenMP version 4.5 or
+ later.
+
libc++ ABI Feature Options
--------------------------
diff --git a/libcxx/docs/UsingLibcxx.rst b/libcxx/docs/UsingLibcxx.rst
index 4d7d70e1d7901d4..8b17bb48ee9fba0 100644
--- a/libcxx/docs/UsingLibcxx.rst
+++ b/libcxx/docs/UsingLibcxx.rst
@@ -600,6 +600,113 @@ Unpoisoning may not be an option, if (for example) you are not maintaining the a
* You are using allocator, which does not call destructor during deallocation.
* You are aware that memory allocated with an allocator may be accessed, even when unused by container.
+Offloading C++ Parallel Algorithms to GPUs
+------------------------------------------
+
+Experimental support for GPU offloading has been added to ``libc++``. The
+implementation uses OpenMP target offloading to leverage GPU compute resources.
+The OpenMP PSTL backend can target both NVIDIA and AMD GPUs.
+However, the implementation only supports contiguous iterators, such as
+iterators for ``std::vector`` or ``std::array``.
+To enable the OpenMP offloading backend it must be selected with
+``LIBCXX_PSTL_BACKEND=openmp`` when installing ``libc++``. Further, when
+compiling a program, the user must specify the command line options
+``-fopenmp -fexperimental-library -stdlib=libc++``. To install LLVM with OpenMP
+offloading enabled, please read
+`the LLVM OpenMP FAQ. <https://openmp.llvm.org/SupportAndFAQ.html>`_
+You may also want to to visit
+`the OpenMP offloading command-line argument reference. <https://openmp.llvm.org/CommandLineArgumentReference.html#offload-command-line-arguments>`_
+
+Example
+~~~~~~~
+
+The following is an example of offloading vector addition to a GPU using our
+standard library extension.
+
+.. code-block:: cpp
+
+ #include <algorithm>
+ #include <execution>
+
+ template<typename T1, typename T2, typename T3>
+ void axpy(const T1 a,std::vector<T2>& x, std::vector<T3>& y)
+ {
+ std::transform(std::execution::par_unseq,x.begin(),x.end(), y.begin(), y.begin(),
+ [=](T2 xi, T3 yi){ return a*xi + yi; });
+ }
+
+The execution policy ``std::execution::par_unseq`` states that the algorithm's
+execution may be parallelized, vectorized, and migrated across threads. This is
+the only execution mode that is safe to offload to GPUs, and for all other
+execution modes the algorithms will execute on the CPU.
+Special attention must be paid to the lambda captures when enabling GPU
+offloading. If the lambda captures by reference, the user must manually map the
+variables to the device. If capturing by reference, the above example could
+be implemented in the following way.
+
+.. code-block:: cpp
+
+ template<typename T1, typename T2, typename T3>
+ void axpy(const T1 a,std::vector<T2>& x, std::vector<T3>& y)
+ {
+ # pragma omp target data map(to:a)
+ std::transform(std::execution::par_unseq,x.begin(),x.end(), y.begin(), y.begin(),
+ [&](T2 xi, T3 yi){ return a*xi + yi; });
+ }
+
+However, if unified shared memory, USM, is enabled, no additional data mapping
+is necessary when capturing y reference.
+
+Compiling functions for GPUs with OpenMP
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+The C++ standard defines that all accesses to memory are inside a single address
+space. However, discrete GPU systems have distinct address spaces. A single
+address space can be emulated if your system supports unified shared memory.
+However, many discrete GPU systems do not, and in those cases it is important to
+pass device function pointers to the parallel algorithms. Below is an example of
+how the OpenMP `declare target` directive can be used to mark that a function
+should be compiled for both host and device. The device address of a function
+pointer can be obtained with `target map(from:<list of identifiers>)`.
+
+.. code-block:: cpp
+
+ // Declare that the function must be compiled for both host and device
+ #pragma omp declare target
+ void cube(int& n) {n*=n*n; };
+ #pragma omp end declare target
+
+ int main()
+ {
+ int * a = new int[LEN];
+ // Initialize the array to 2 on the device
+ std::fill(std::execution::par_unseq,a, a+LEN,2);
+ // Get the device pointer for cube
+ void (*dcube)(int& n);
+ #pragma omp target map(from:dcube)
+ dcube = &cube;
+ // Pass the device function pointer to the parallel algorithm
+ std::for_each(std::execution::par_unseq,a, a+LEN,dcube);
+ // Validate that the result is 8 on the host for all array indices
+ std::for_each(std::execution::par,a, a+LEN,[&](int & n){
+ assert(n == 8);
+ });
+ delete[] a;
+ return 0;
+ }
+
+Without unified shared memory, the above example will not work if the host
+function pointer `cube` is passed to the parallel algorithm.
+
+Important notes about exception handling
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+GPU architectures do not support exception handling. If compiling a program
+containing parallel algorithms with ``clang`` 18 or newer, a program with
+exceptions in offloaded code regions will compile, but the program will
+terminate if an exception is thrown on the device. This does not conform with
+the C++ standard and exception handling on GPUs will hopefully be better
+supported in future releases of LLVM.
+
Platform specific behavior
==========================
>From 62ab21932c45339016b4834d3028baeb3334e4ef Mon Sep 17 00:00:00 2001
From: AntonRydahl <rydahl2610 at gmail.com>
Date: Fri, 20 Oct 2023 11:26:26 -0700
Subject: [PATCH 19/26] Changed argument names to reflect input and output
---
.../pstl_backends/openmp/backend.h | 15 +++---
.../__algorithm/pstl_backends/openmp/fill.h | 20 +++++---
.../pstl_backends/openmp/find_if.h | 5 +-
.../pstl_backends/openmp/for_each.h | 17 +++++--
.../pstl_backends/openmp/omp_offload.h | 21 +-------
.../pstl_backends/openmp/transform.h | 51 +++++++++++++------
.../pstl_backends/openmp/transform_reduce.h | 20 ++++----
7 files changed, 85 insertions(+), 64 deletions(-)
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/backend.h b/libcxx/include/__algorithm/pstl_backends/openmp/backend.h
index 9396f91b1a755f2..99245a7d13e9917 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/backend.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/backend.h
@@ -20,13 +20,14 @@
#if _LIBCPP_STD_VER >= 17
-#if defined(_LIBCPP_PSTL_BACKEND_OPENMP)
-# if !defined(_OPENMP)
-//# warning "PSTL is configured to use the OpenMP backend, but OpenMP is not enabled. Did you compile with -fopenmp?"
-# elif (defined(_OPENMP) && _OPENMP < 201511)
-//# warning "OpenMP target offloading has been supported since OpenMP version 4.5 (201511). Please use a more recent version of OpenMP."
-# endif
-#endif
+# if defined(_LIBCPP_PSTL_BACKEND_OPENMP)
+# if !defined(_OPENMP)
+// # warning "PSTL is configured to use the OpenMP backend, but OpenMP is not enabled. Did you compile with -fopenmp?"
+# elif (defined(_OPENMP) && _OPENMP < 201511)
+// # warning "OpenMP target offloading has been supported since OpenMP version 4.5 (201511). Please use a more recent
+// version of OpenMP."
+# endif
+# endif
_LIBCPP_BEGIN_NAMESPACE_STD
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/fill.h b/libcxx/include/__algorithm/pstl_backends/openmp/fill.h
index e8101233e342a3e..4262f778fa9121c 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/fill.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/fill.h
@@ -27,18 +27,26 @@
_LIBCPP_BEGIN_NAMESPACE_STD
+template <class _Tp, class _DifferenceType, class _Up>
+_LIBCPP_HIDE_FROM_ABI _Tp* __omp_fill(_Tp* __out1, _DifferenceType __n, const _Up& __value) noexcept {
+ __par_backend::__omp_map_alloc(__out1, __n);
+# pragma omp target teams distribute parallel for simd
+ for (_DifferenceType __i = 0; __i < __n; ++__i)
+ *(__out1 + __i) = __value;
+ __par_backend::__omp_map_from(__out1, __n);
+ return __out1 + __n;
+}
+
template <class _ExecutionPolicy, class _ForwardIterator, class _Tp>
_LIBCPP_HIDE_FROM_ABI optional<__empty>
__pstl_fill(__omp_backend_tag, _ForwardIterator __first, _ForwardIterator __last, const _Tp& __value) {
- // It is only safe to execute fill on the GPU, it the execution policy is
- // parallel unsequenced, as it is the only execution policy allowing
- // SIMD instructions
+ // If it is safe to offload the computations to the GPU, we call the OpenMP
+ // implementation of for_each. In the case of fill, we provide for_Each with a
+ // lambda returning a constant.
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__is_parallel_execution_policy_v<_ExecutionPolicy> &&
__libcpp_is_contiguous_iterator<_ForwardIterator>::value) {
- std::__rewrap_iter(__first, __par_backend::__omp_for_each(std::__unwrap_iter(__first), __last - __first, [&](std::remove_pointer_t<decltype(std::__unwrap_iter(__first))>& e) {
- e = __value;
- }));
+ std::__rewrap_iter(__first, std::__omp_fill(std::__unwrap_iter(__first), __last - __first, __value));
return __empty{};
}
// Otherwise, we execute fill on the CPU instead
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h b/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h
index f07965885c9c68c..8d7b196ec176f71 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h
@@ -34,17 +34,20 @@ _LIBCPP_HIDE_FROM_ABI _Tp* __omp_find_if(_Tp* __first, _DifferenceType __n, _Pre
idx = (__i < idx) ? __i : idx;
}
}
- __par_backend::__omp_map_free(__first, __n);
+ __par_backend::__omp_map_release(__first, __n);
return __first + idx;
}
template <class _ExecutionPolicy, class _ForwardIterator, class _Predicate>
_LIBCPP_HIDE_FROM_ABI optional<_ForwardIterator>
__pstl_find_if(__omp_backend_tag, _ForwardIterator __first, _ForwardIterator __last, _Predicate __pred) {
+ // If it is safe to offload the computations to the GPU, we call the OpenMP
+ // implementation of find_if
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__is_parallel_execution_policy_v<_ExecutionPolicy> &&
__libcpp_is_contiguous_iterator<_ForwardIterator>::value) {
return std::__rewrap_iter(__first, std::__omp_find_if(std::__unwrap_iter(__first), __last - __first, __pred));
+ // Else we rey on the CPU PSTL backend
} else {
return std::__pstl_find_if<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __pred);
}
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h b/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h
index eb8caf23971cb33..f64efc170537af6 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h
@@ -26,16 +26,25 @@
_LIBCPP_BEGIN_NAMESPACE_STD
+template <class _Tp, class _DifferenceType, class _Function>
+_LIBCPP_HIDE_FROM_ABI _Tp* __omp_for_each(_Tp* __inout1, _DifferenceType __n, _Function __f) noexcept {
+ __par_backend::__omp_map_to(__inout1, __n);
+# pragma omp target teams distribute parallel for simd
+ for (_DifferenceType __i = 0; __i < __n; ++__i)
+ __f(*(__inout1 + __i));
+ __par_backend::__omp_map_from(__inout1, __n);
+ return __inout1 + __n;
+}
+
template <class _ExecutionPolicy, class _ForwardIterator, class _Functor>
_LIBCPP_HIDE_FROM_ABI optional<__empty>
__pstl_for_each(__omp_backend_tag, _ForwardIterator __first, _ForwardIterator __last, _Functor __func) {
- // It is only safe to execute for_each on the GPU, it the execution policy is
- // parallel unsequenced, as it is the only execution policy prohibiting throwing
- // exceptions and allowing SIMD instructions
+ // If it is safe to offload the computations to the GPU, we call the OpenMP
+ // implementation of for_each
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__libcpp_is_contiguous_iterator<_ForwardIterator>::value &&
__libcpp_is_contiguous_iterator<_ForwardIterator>::value) {
- __par_backend::__omp_for_each(std::__unwrap_iter(__first), __last - __first, __func);
+ std::__omp_for_each(std::__unwrap_iter(__first), __last - __first, __func);
return __empty{};
}
// Else we fall back to the serial backend
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/omp_offload.h b/libcxx/include/__algorithm/pstl_backends/openmp/omp_offload.h
index 2e44af3c9a761f5..88ee4cdbbc4faec 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/omp_offload.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/omp_offload.h
@@ -23,10 +23,6 @@
#include <__utility/move.h>
#include <cstddef>
-// is_same
-
-// __libcpp_is_contiguous_iterator
-
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
@@ -70,26 +66,11 @@ __omp_map_alloc([[maybe_unused]] const _Iterator p, [[maybe_unused]] const _Diff
template <class _Iterator, class _DifferenceType>
_LIBCPP_HIDE_FROM_ABI void
-__omp_map_free([[maybe_unused]] const _Iterator p, [[maybe_unused]] const _DifferenceType len) noexcept {
+__omp_map_release([[maybe_unused]] const _Iterator p, [[maybe_unused]] const _DifferenceType len) noexcept {
static_assert(__libcpp_is_contiguous_iterator<_Iterator>::value);
# pragma omp target exit data map(release : p[0 : len])
}
-//===----------------------------------------------------------------------===//
-// The OpenMP implementation of for_each is shared between for_each and fill
-//===----------------------------------------------------------------------===//
-
-template <class _Tp, class _DifferenceType, class _Function>
-_LIBCPP_HIDE_FROM_ABI _Tp*
-__omp_for_each(_Tp* __first, _DifferenceType __n, _Function __f) noexcept {
- __par_backend::__omp_map_to(__first, __n);
-# pragma omp target teams distribute parallel for simd
- for (_DifferenceType __i = 0; __i < __n; ++__i)
- __f(*(__first + __i));
- __par_backend::__omp_map_from(__first, __n);
- return __first + __n;
-}
-
} // namespace __omp_gpu_backend
} // namespace __par_backend
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/transform.h b/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
index f7e52d7933b6c40..bd795d5571f0d79 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
@@ -33,29 +33,45 @@ _LIBCPP_BEGIN_NAMESPACE_STD
template <class _Tp, class _DifferenceType, class _Up, class _Function>
_LIBCPP_HIDE_FROM_ABI optional<__empty>
-__omp_transform(_Tp* __first1, _DifferenceType __n, _Up* __first2, _Function __f) noexcept {
- __par_backend::__omp_map_alloc(__first2, __n);
- __par_backend::__omp_map_to(__first1, __n);
+__omp_transform(_Tp* __in1, _DifferenceType __n, _Up* __out1, _Function __f) noexcept {
+ // The order of the following maps matter, as we wish to move the data. If
+ // they were placed in the reverse order, and __in equals __out, then we would
+ // allocate the buffer on the device without copying the data.
+ __par_backend::__omp_map_to(__in1, __n);
+ __par_backend::__omp_map_alloc(__out1, __n);
# pragma omp target teams distribute parallel for simd
for (_DifferenceType __i = 0; __i < __n; ++__i)
- *(__first2 + __i) = __f(*(__first1 + __i));
- __par_backend::__omp_map_from(__first2, __n);
- __par_backend::__omp_map_free(__first1, __n);
+ *(__out1 + __i) = __f(*(__in1 + __i));
+ // The order of the following two maps matters, since the user could legally
+ // overwrite __in The "release" map modifier decreases the reference counter
+ // by one, and "from" only moves the data to the host, when the reference
+ // count is decremented to zero.
+ __par_backend::__omp_map_release(__in1, __n);
+ __par_backend::__omp_map_from(__out1, __n);
return __empty{};
}
template <class _Tp, class _DifferenceType, class _Up, class _Vp, class _Function>
_LIBCPP_HIDE_FROM_ABI optional<__empty>
-__omp_transform(_Tp* __first1, _DifferenceType __n, _Up* __first2, _Vp* __first3, _Function __f) noexcept {
- __par_backend::__omp_map_to(__first1, __n);
- __par_backend::__omp_map_to(__first2, __n);
- __par_backend::__omp_map_alloc(__first3, __n);
+__omp_transform(_Tp* __in1, _DifferenceType __n, _Up* __in2, _Vp* __out1, _Function __f) noexcept {
+ // The order of the following maps matter, as we wish to move the data. If
+ // they were placed in the reverse order, and __out equals __in1 or __in2,
+ // then we would allocate one of the buffer on the device without copying the
+ // data.
+ __par_backend::__omp_map_to(__in1, __n);
+ __par_backend::__omp_map_to(__in2, __n);
+ __par_backend::__omp_map_alloc(__out1, __n);
# pragma omp target teams distribute parallel for simd
for (_DifferenceType __i = 0; __i < __n; ++__i)
- *(__first3 + __i) = __f(*(__first1 + __i), *(__first2 + __i));
- __par_backend::__omp_map_free(__first1, __n);
- __par_backend::__omp_map_free(__first2, __n);
- __par_backend::__omp_map_from(__first3, __n);
+ *(__out1 + __i) = __f(*(__in1 + __i), *(__in2 + __i));
+ // The order of the following three maps matters, since the user could legally
+ // overwrite either of the inputs if __out equals __in1 or __in2. The
+ // "release" map modifier decreases the reference counter by one, and "from"
+ // only moves the data from the device, when the reference count is
+ // decremented to zero.
+ __par_backend::__omp_map_release(__in1, __n);
+ __par_backend::__omp_map_release(__in2, __n);
+ __par_backend::__omp_map_from(__out1, __n);
return __empty{};
}
@@ -95,7 +111,12 @@ _LIBCPP_HIDE_FROM_ABI optional<_ForwardOutIterator> __pstl_transform(
__libcpp_is_contiguous_iterator<_ForwardIterator1>::value &&
__libcpp_is_contiguous_iterator<_ForwardIterator2>::value &&
__libcpp_is_contiguous_iterator<_ForwardOutIterator>::value) {
- std::__omp_transform(std::__unwrap_iter(__first1), __last1 - __first1, std::__unwrap_iter(__first2), std::__unwrap_iter(__result), __op);
+ std::__omp_transform(
+ std::__unwrap_iter(__first1),
+ __last1 - __first1,
+ std::__unwrap_iter(__first2),
+ std::__unwrap_iter(__result),
+ __op);
return __result + (__last1 - __first1);
}
// If it is not safe to offload to the GPU, we rely on the CPU backend.
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h b/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h
index 3798e1cb3f3fac1..1684c3d273b2239 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h
@@ -39,17 +39,17 @@ _LIBCPP_BEGIN_NAMESPACE_STD
typename _Tp, \
typename _BinaryOperationType, \
typename _UnaryOperation> \
- _LIBCPP_HIDE_FROM_ABI _Tp __omp_transform_reduce( \
+ _LIBCPP_HIDE_FROM_ABI _Tp __omp_transform_reduce( \
_Iterator __first, \
_DifferenceType __n, \
_Tp __init, \
std_op<_BinaryOperationType> __reduce, \
_UnaryOperation __transform) noexcept { \
- __par_backend::__omp_map_to(__first, __n); \
+ __par_backend::__omp_map_to(__first, __n); \
_PSTL_PRAGMA(omp target teams distribute parallel for simd reduction(omp_op:__init)) \
for (_DifferenceType __i = 0; __i < __n; ++__i) \
__init = __reduce(__init, __transform(*(__first + __i))); \
- __par_backend::__omp_map_free(__first, __n); \
+ __par_backend::__omp_map_release(__first, __n); \
return __init; \
}
@@ -60,20 +60,20 @@ _PSTL_PRAGMA(omp target teams distribute parallel for simd reduction(omp_op:__in
typename _Tp, \
typename _BinaryOperationType, \
typename _UnaryOperation > \
- _LIBCPP_HIDE_FROM_ABI _Tp __omp_transform_reduce( \
+ _LIBCPP_HIDE_FROM_ABI _Tp __omp_transform_reduce( \
_Iterator1 __first1, \
_Iterator2 __first2, \
_DifferenceType __n, \
_Tp __init, \
std_op<_BinaryOperationType> __reduce, \
_UnaryOperation __transform) noexcept { \
- __par_backend::__omp_map_to(__first1, __n); \
- __par_backend::__omp_map_to(__first2, __n); \
+ __par_backend::__omp_map_to(__first1, __n); \
+ __par_backend::__omp_map_to(__first2, __n); \
_PSTL_PRAGMA(omp target teams distribute parallel for simd reduction(omp_op:__init)) \
for (_DifferenceType __i = 0; __i < __n; ++__i) \
__init = __reduce(__init, __transform(*(__first1 + __i), *(__first2 + __i))); \
- __par_backend::__omp_map_free(__first1, __n); \
- __par_backend::__omp_map_free(__first2, __n); \
+ __par_backend::__omp_map_release(__first1, __n); \
+ __par_backend::__omp_map_release(__first2, __n); \
return __init; \
}
@@ -145,8 +145,7 @@ _LIBCPP_HIDE_FROM_ABI optional<_Tp> __pstl_transform_reduce(
__is_parallel_execution_policy_v<_ExecutionPolicy> &&
__libcpp_is_contiguous_iterator<_ForwardIterator>::value && is_arithmetic_v<_Tp> &&
__is_supported_reduction<_BinaryOperation, _Tp, _Tp>::value) {
- return std::__omp_transform_reduce(
- std::__unwrap_iter(__first), __last - __first, __init, __reduce, __transform);
+ return std::__omp_transform_reduce(std::__unwrap_iter(__first), __last - __first, __init, __reduce, __transform);
}
return std::__pstl_transform_reduce<_ExecutionPolicy>(
__cpu_backend_tag{}, __first, __last, std::move(__init), __reduce, __transform);
@@ -166,7 +165,6 @@ _LIBCPP_HIDE_FROM_ABI optional<_Tp> __pstl_transform_reduce(
_Tp __init,
_BinaryOperation1 __reduce,
_BinaryOperation2 __transform) {
- // The interface for the function switched between C++17 and C++20
if constexpr (__is_unsequenced_execution_policy_v<_ExecutionPolicy> &&
__is_parallel_execution_policy_v<_ExecutionPolicy> &&
__libcpp_is_contiguous_iterator<_ForwardIterator1>::value &&
>From dd894b6872aea647604f6085be26d7aae98ffb0e Mon Sep 17 00:00:00 2001
From: AntonRydahl <rydahl2610 at gmail.com>
Date: Fri, 20 Oct 2023 11:42:13 -0700
Subject: [PATCH 20/26] Adding compile time errors to
pstl_backend/openmp/backend.h to validate that OpenMP is enabled
---
libcxx/docs/UsingLibcxx.rst | 1 +
libcxx/include/__algorithm/pstl_backends/openmp/backend.h | 5 ++---
2 files changed, 3 insertions(+), 3 deletions(-)
diff --git a/libcxx/docs/UsingLibcxx.rst b/libcxx/docs/UsingLibcxx.rst
index 8b17bb48ee9fba0..27c3983e5637941 100644
--- a/libcxx/docs/UsingLibcxx.rst
+++ b/libcxx/docs/UsingLibcxx.rst
@@ -659,6 +659,7 @@ is necessary when capturing y reference.
Compiling functions for GPUs with OpenMP
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
The C++ standard defines that all accesses to memory are inside a single address
space. However, discrete GPU systems have distinct address spaces. A single
address space can be emulated if your system supports unified shared memory.
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/backend.h b/libcxx/include/__algorithm/pstl_backends/openmp/backend.h
index 99245a7d13e9917..11ab0bb108b2251 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/backend.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/backend.h
@@ -22,10 +22,9 @@
# if defined(_LIBCPP_PSTL_BACKEND_OPENMP)
# if !defined(_OPENMP)
-// # warning "PSTL is configured to use the OpenMP backend, but OpenMP is not enabled. Did you compile with -fopenmp?"
+# error "PSTL is configured to use the OpenMP backend, but OpenMP is not enabled. Did you compile with -fopenmp?"
# elif (defined(_OPENMP) && _OPENMP < 201511)
-// # warning "OpenMP target offloading has been supported since OpenMP version 4.5 (201511). Please use a more recent
-// version of OpenMP."
+# error "OpenMP target offloading has been supported since OpenMP version 4.5 (201511). Please use a more recent version of OpenMP."
# endif
# endif
>From d282ab15cf55fb06e9c6ab81d6e8aad3a6930559 Mon Sep 17 00:00:00 2001
From: AntonRydahl <rydahl2610 at gmail.com>
Date: Fri, 20 Oct 2023 11:58:27 -0700
Subject: [PATCH 21/26] Clang-formatted error message in backend.h
---
libcxx/include/__algorithm/pstl_backends/openmp/backend.h | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/backend.h b/libcxx/include/__algorithm/pstl_backends/openmp/backend.h
index 11ab0bb108b2251..eb5e40d6f20a94d 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/backend.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/backend.h
@@ -22,9 +22,10 @@
# if defined(_LIBCPP_PSTL_BACKEND_OPENMP)
# if !defined(_OPENMP)
-# error "PSTL is configured to use the OpenMP backend, but OpenMP is not enabled. Did you compile with -fopenmp?"
+# error "PSTL is configured to use the OpenMP backend, but OpenMP is not enabled. Did you compile with -fopenmp?"
# elif (defined(_OPENMP) && _OPENMP < 201511)
-# error "OpenMP target offloading has been supported since OpenMP version 4.5 (201511). Please use a more recent version of OpenMP."
+# error \
+ "OpenMP target offloading has been supported since OpenMP version 4.5 (201511). Please use a more recent version of OpenMP."
# endif
# endif
>From 4d41118c6b9f7f8f27240a6bab715afba9fa4f47 Mon Sep 17 00:00:00 2001
From: AntonRydahl <rydahl2610 at gmail.com>
Date: Fri, 20 Oct 2023 12:48:16 -0700
Subject: [PATCH 22/26] Disabling ADL in pstl_backends/openmp/stable_sort.h
---
libcxx/include/__algorithm/pstl_backends/openmp/stable_sort.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/stable_sort.h b/libcxx/include/__algorithm/pstl_backends/openmp/stable_sort.h
index a4c6a2bff9f92fd..0b5ce39a2344a9a 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/stable_sort.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/stable_sort.h
@@ -28,7 +28,7 @@ template <class _ExecutionPolicy, class _RandomAccessIterator, class _Comp>
_LIBCPP_HIDE_FROM_ABI optional<__empty>
__pstl_stable_sort(__omp_backend_tag, _RandomAccessIterator __first, _RandomAccessIterator __last, _Comp __comp) {
// TODO: Implement GPU backend.
- return __pstl_stable_sort<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __comp);
+ return std::__pstl_stable_sort<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __comp);
}
_LIBCPP_END_NAMESPACE_STD
>From d3abcc55d0a785663e858b3983589ea3a321dc2a Mon Sep 17 00:00:00 2001
From: AntonRydahl <rydahl2610 at gmail.com>
Date: Fri, 20 Oct 2023 12:54:28 -0700
Subject: [PATCH 23/26] Added std::__rewrap_iter to std::transform
---
.../__algorithm/pstl_backends/openmp/transform.h | 16 +++++++---------
1 file changed, 7 insertions(+), 9 deletions(-)
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/transform.h b/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
index bd795d5571f0d79..0338771728d9d0a 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
@@ -32,7 +32,7 @@ _LIBCPP_BEGIN_NAMESPACE_STD
//===----------------------------------------------------------------------===//
template <class _Tp, class _DifferenceType, class _Up, class _Function>
-_LIBCPP_HIDE_FROM_ABI optional<__empty>
+_LIBCPP_HIDE_FROM_ABI _Tp*
__omp_transform(_Tp* __in1, _DifferenceType __n, _Up* __out1, _Function __f) noexcept {
// The order of the following maps matter, as we wish to move the data. If
// they were placed in the reverse order, and __in equals __out, then we would
@@ -48,11 +48,11 @@ __omp_transform(_Tp* __in1, _DifferenceType __n, _Up* __out1, _Function __f) noe
// count is decremented to zero.
__par_backend::__omp_map_release(__in1, __n);
__par_backend::__omp_map_from(__out1, __n);
- return __empty{};
+ return __out1 + __n;
}
template <class _Tp, class _DifferenceType, class _Up, class _Vp, class _Function>
-_LIBCPP_HIDE_FROM_ABI optional<__empty>
+_LIBCPP_HIDE_FROM_ABI _Tp*
__omp_transform(_Tp* __in1, _DifferenceType __n, _Up* __in2, _Vp* __out1, _Function __f) noexcept {
// The order of the following maps matter, as we wish to move the data. If
// they were placed in the reverse order, and __out equals __in1 or __in2,
@@ -72,7 +72,7 @@ __omp_transform(_Tp* __in1, _DifferenceType __n, _Up* __in2, _Vp* __out1, _Funct
__par_backend::__omp_map_release(__in1, __n);
__par_backend::__omp_map_release(__in2, __n);
__par_backend::__omp_map_from(__out1, __n);
- return __empty{};
+ return __out1 + __n;
}
template <class _ExecutionPolicy, class _ForwardIterator, class _ForwardOutIterator, class _UnaryOperation>
@@ -86,8 +86,7 @@ _LIBCPP_HIDE_FROM_ABI optional<_ForwardOutIterator> __pstl_transform(
__is_parallel_execution_policy_v<_ExecutionPolicy> &&
__libcpp_is_contiguous_iterator<_ForwardIterator>::value &&
__libcpp_is_contiguous_iterator<_ForwardOutIterator>::value) {
- std::__omp_transform(std::__unwrap_iter(__first), __last - __first, std::__unwrap_iter(__result), __op);
- return __result + (__last - __first);
+ std::__rewrap_iter(__result,std::__omp_transform(std::__unwrap_iter(__first), __last - __first, std::__unwrap_iter(__result), __op));
}
// If it is not safe to offload to the GPU, we rely on the CPU backend.
return std::__pstl_transform<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __result, __op);
@@ -111,13 +110,12 @@ _LIBCPP_HIDE_FROM_ABI optional<_ForwardOutIterator> __pstl_transform(
__libcpp_is_contiguous_iterator<_ForwardIterator1>::value &&
__libcpp_is_contiguous_iterator<_ForwardIterator2>::value &&
__libcpp_is_contiguous_iterator<_ForwardOutIterator>::value) {
- std::__omp_transform(
+ return std::__rewrap_iter(__result,std::__omp_transform(
std::__unwrap_iter(__first1),
__last1 - __first1,
std::__unwrap_iter(__first2),
std::__unwrap_iter(__result),
- __op);
- return __result + (__last1 - __first1);
+ __op));
}
// If it is not safe to offload to the GPU, we rely on the CPU backend.
return std::__pstl_transform<_ExecutionPolicy>(__cpu_backend_tag{}, __first1, __last1, __first2, __result, __op);
>From 7711c9117c84ae6e1701642b76524b15c03102df Mon Sep 17 00:00:00 2001
From: AntonRydahl <rydahl2610 at gmail.com>
Date: Fri, 20 Oct 2023 13:17:56 -0700
Subject: [PATCH 24/26] Clang-formatted
libcxx/include/__algorithm/pstl_backends/openmp/transform.h
---
.../pstl_backends/openmp/transform.h | 21 +++++++++++--------
1 file changed, 12 insertions(+), 9 deletions(-)
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/transform.h b/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
index 0338771728d9d0a..e1c5f54675b3870 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
@@ -32,8 +32,7 @@ _LIBCPP_BEGIN_NAMESPACE_STD
//===----------------------------------------------------------------------===//
template <class _Tp, class _DifferenceType, class _Up, class _Function>
-_LIBCPP_HIDE_FROM_ABI _Tp*
-__omp_transform(_Tp* __in1, _DifferenceType __n, _Up* __out1, _Function __f) noexcept {
+_LIBCPP_HIDE_FROM_ABI _Tp* __omp_transform(_Tp* __in1, _DifferenceType __n, _Up* __out1, _Function __f) noexcept {
// The order of the following maps matter, as we wish to move the data. If
// they were placed in the reverse order, and __in equals __out, then we would
// allocate the buffer on the device without copying the data.
@@ -86,7 +85,9 @@ _LIBCPP_HIDE_FROM_ABI optional<_ForwardOutIterator> __pstl_transform(
__is_parallel_execution_policy_v<_ExecutionPolicy> &&
__libcpp_is_contiguous_iterator<_ForwardIterator>::value &&
__libcpp_is_contiguous_iterator<_ForwardOutIterator>::value) {
- std::__rewrap_iter(__result,std::__omp_transform(std::__unwrap_iter(__first), __last - __first, std::__unwrap_iter(__result), __op));
+ std::__rewrap_iter(
+ __result,
+ std::__omp_transform(std::__unwrap_iter(__first), __last - __first, std::__unwrap_iter(__result), __op));
}
// If it is not safe to offload to the GPU, we rely on the CPU backend.
return std::__pstl_transform<_ExecutionPolicy>(__cpu_backend_tag{}, __first, __last, __result, __op);
@@ -110,12 +111,14 @@ _LIBCPP_HIDE_FROM_ABI optional<_ForwardOutIterator> __pstl_transform(
__libcpp_is_contiguous_iterator<_ForwardIterator1>::value &&
__libcpp_is_contiguous_iterator<_ForwardIterator2>::value &&
__libcpp_is_contiguous_iterator<_ForwardOutIterator>::value) {
- return std::__rewrap_iter(__result,std::__omp_transform(
- std::__unwrap_iter(__first1),
- __last1 - __first1,
- std::__unwrap_iter(__first2),
- std::__unwrap_iter(__result),
- __op));
+ return std::__rewrap_iter(
+ __result,
+ std::__omp_transform(
+ std::__unwrap_iter(__first1),
+ __last1 - __first1,
+ std::__unwrap_iter(__first2),
+ std::__unwrap_iter(__result),
+ __op));
}
// If it is not safe to offload to the GPU, we rely on the CPU backend.
return std::__pstl_transform<_ExecutionPolicy>(__cpu_backend_tag{}, __first1, __last1, __first2, __result, __op);
>From 72c2f24e2666ff703eb515b22221d49932991825 Mon Sep 17 00:00:00 2001
From: AntonRydahl <rydahl2610 at gmail.com>
Date: Fri, 20 Oct 2023 14:40:03 -0700
Subject: [PATCH 25/26] Fixing errors detected by C++26 buildbot
---
.../__algorithm/pstl_backends/openmp/find_if.h | 8 ++++----
.../pstl_backends/openmp/omp_offload.h | 16 ++++++++--------
2 files changed, 12 insertions(+), 12 deletions(-)
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h b/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h
index 8d7b196ec176f71..b86c6cbebf2201b 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h
@@ -27,15 +27,15 @@ _LIBCPP_BEGIN_NAMESPACE_STD
template <class _Tp, class _DifferenceType, class _Predicate>
_LIBCPP_HIDE_FROM_ABI _Tp* __omp_find_if(_Tp* __first, _DifferenceType __n, _Predicate __pred) noexcept {
__par_backend::__omp_map_to(__first, __n);
- _DifferenceType idx = __n;
-# pragma omp target teams distribute parallel for simd reduction(min : idx)
+ _DifferenceType __idx = __n;
+# pragma omp target teams distribute parallel for simd reduction(min : __idx)
for (_DifferenceType __i = 0; __i < __n; ++__i) {
if (__pred(*(__first + __i))) {
- idx = (__i < idx) ? __i : idx;
+ __idx = (__i < __idx) ? __i : __idx;
}
}
__par_backend::__omp_map_release(__first, __n);
- return __first + idx;
+ return __first + __idx;
}
template <class _ExecutionPolicy, class _ForwardIterator, class _Predicate>
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/omp_offload.h b/libcxx/include/__algorithm/pstl_backends/openmp/omp_offload.h
index 88ee4cdbbc4faec..99ac28a7a33ead3 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/omp_offload.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/omp_offload.h
@@ -45,30 +45,30 @@ inline namespace __omp_gpu_backend {
template <class _Iterator, class _DifferenceType>
_LIBCPP_HIDE_FROM_ABI void
-__omp_map_to([[maybe_unused]] const _Iterator p, [[maybe_unused]] const _DifferenceType len) noexcept {
+__omp_map_to([[maybe_unused]] const _Iterator __p, [[maybe_unused]] const _DifferenceType __len) noexcept {
static_assert(__libcpp_is_contiguous_iterator<_Iterator>::value);
-# pragma omp target enter data map(to : p[0 : len])
+# pragma omp target enter data map(to : __p [0:__len])
}
template <class _Iterator, class _DifferenceType>
_LIBCPP_HIDE_FROM_ABI void
-__omp_map_from([[maybe_unused]] const _Iterator p, [[maybe_unused]] const _DifferenceType len) noexcept {
+__omp_map_from([[maybe_unused]] const _Iterator __p, [[maybe_unused]] const _DifferenceType __len) noexcept {
static_assert(__libcpp_is_contiguous_iterator<_Iterator>::value);
-# pragma omp target exit data map(from : p[0 : len])
+# pragma omp target exit data map(from : __p [0:__len])
}
template <class _Iterator, class _DifferenceType>
_LIBCPP_HIDE_FROM_ABI void
-__omp_map_alloc([[maybe_unused]] const _Iterator p, [[maybe_unused]] const _DifferenceType len) noexcept {
+__omp_map_alloc([[maybe_unused]] const _Iterator __p, [[maybe_unused]] const _DifferenceType __len) noexcept {
static_assert(__libcpp_is_contiguous_iterator<_Iterator>::value);
-# pragma omp target enter data map(alloc : p[0 : len])
+# pragma omp target enter data map(alloc : __p [0:__len])
}
template <class _Iterator, class _DifferenceType>
_LIBCPP_HIDE_FROM_ABI void
-__omp_map_release([[maybe_unused]] const _Iterator p, [[maybe_unused]] const _DifferenceType len) noexcept {
+__omp_map_release([[maybe_unused]] const _Iterator __p, [[maybe_unused]] const _DifferenceType __len) noexcept {
static_assert(__libcpp_is_contiguous_iterator<_Iterator>::value);
-# pragma omp target exit data map(release : p[0 : len])
+# pragma omp target exit data map(release : __p [0:__len])
}
} // namespace __omp_gpu_backend
>From f989eec7b2d46ce76c9d420b22bdba35faeee25e Mon Sep 17 00:00:00 2001
From: AntonRydahl <rydahl2610 at gmail.com>
Date: Mon, 23 Oct 2023 11:05:33 -0700
Subject: [PATCH 26/26] Updating includes once more after refactorings
---
.../__algorithm/pstl_backends/openmp.h | 35 +++++++++++++++++++
.../__algorithm/pstl_backends/openmp/fill.h | 1 +
.../pstl_backends/openmp/find_if.h | 1 +
.../pstl_backends/openmp/for_each.h | 1 +
.../pstl_backends/openmp/omp_offload.h | 27 ++++----------
.../pstl_backends/openmp/transform.h | 1 +
.../pstl_backends/openmp/transform_reduce.h | 2 ++
7 files changed, 47 insertions(+), 21 deletions(-)
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp.h b/libcxx/include/__algorithm/pstl_backends/openmp.h
index 9e5490db655f4bd..a1d015e056837b9 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp.h
@@ -11,6 +11,41 @@
#include <__config>
+/*
+Combined OpenMP CPU and GPU Backend
+===================================
+Contrary to the CPU backends found in ./cpu_backends/, the OpenMP backend can
+target both CPUs and GPUs. The OpenMP standard defines that when offloading code
+to an accelerator, the compiler must generate a fallback code for execution on
+the host. Thereby, the backend works as a CPU backend if no targeted accelerator
+is available at execution time. The target regions can also be compiled directly
+for a CPU architecture, for instance by adding the command-line option
+`-fopenmp-targets=x86_64-pc-linux-gnu` in Clang.
+
+Implicit Assumptions
+--------------------
+If the user provides a function pointer as an argument to a parallel algorithm,
+it is assumed that it is the device pointer as there is currently no way to
+check whether a host or device pointer was passed.
+
+Mapping Clauses
+---------------
+In some of the parallel algorithms, the user is allowed to provide the same
+iterator as input and output. Hence, the order of the maps matters. Therefore,
+`pragma omp target data map(to:...)` must be used before
+`pragma omp target data map(alloc:...)`. Conversely, the maps with map modifier
+`release` must be placed before the maps with map modifier `from` when
+transferring the result from the device to the host.
+
+Exceptions
+----------
+Currently, GPU architectures do not handle exceptions. OpenMP target regions are
+allowed to contain try/catch statements and throw expressions in Clang, but if a
+throw expression is reached, it will terminate the program. That does not
+conform with the C++ standard.
+
+*/
+
#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__algorithm/pstl_backends/openmp/any_of.h>
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/fill.h b/libcxx/include/__algorithm/pstl_backends/openmp/fill.h
index 4262f778fa9121c..53de1284acc60b8 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/fill.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/fill.h
@@ -12,6 +12,7 @@
#include <__algorithm/fill.h>
#include <__algorithm/pstl_backends/cpu_backends/backend.h>
#include <__algorithm/pstl_backends/openmp/backend.h>
+#include <__algorithm/unwrap_iter.h>
#include <__config>
#include <__iterator/wrap_iter.h>
#include <__type_traits/is_execution_policy.h>
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h b/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h
index b86c6cbebf2201b..db128e058823db7 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/find_if.h
@@ -12,6 +12,7 @@
#include <__algorithm/find_if.h>
#include <__algorithm/pstl_backends/cpu_backends/backend.h>
#include <__algorithm/pstl_backends/openmp/backend.h>
+#include <__algorithm/unwrap_iter.h>
#include <__config>
#include <__iterator/wrap_iter.h>
#include <optional>
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h b/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h
index f64efc170537af6..ef73b864773fc10 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/for_each.h
@@ -12,6 +12,7 @@
#include <__algorithm/for_each.h>
#include <__algorithm/pstl_backends/cpu_backends/backend.h>
#include <__algorithm/pstl_backends/openmp/backend.h>
+#include <__algorithm/unwrap_iter.h>
#include <__config>
#include <__iterator/wrap_iter.h>
#include <__type_traits/is_execution_policy.h>
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/omp_offload.h b/libcxx/include/__algorithm/pstl_backends/openmp/omp_offload.h
index 99ac28a7a33ead3..d47fdcd39c39b25 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/omp_offload.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/omp_offload.h
@@ -9,33 +9,20 @@
#ifndef _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_OMP_OFFLOAD_H
#define _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_OMP_OFFLOAD_H
-#include <__algorithm/unwrap_iter.h>
#include <__assert>
#include <__config>
-#include <__functional/operations.h>
#include <__iterator/iterator_traits.h>
-#include <__iterator/wrap_iter.h>
-#include <__memory/addressof.h>
-#include <__memory/pointer_traits.h>
-#include <__type_traits/is_pointer.h>
-#include <__type_traits/is_same.h>
-#include <__utility/empty.h>
-#include <__utility/move.h>
-#include <cstddef>
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
# pragma GCC system_header
#endif
-_LIBCPP_PUSH_MACROS
-#include <__undef_macros>
-
#if !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && _LIBCPP_STD_VER >= 17
_LIBCPP_BEGIN_NAMESPACE_STD
namespace __par_backend {
-inline namespace __omp_gpu_backend {
+inline namespace __omp_backend {
//===----------------------------------------------------------------------===//
// The following four functions can be used to map contiguous array sections to
@@ -47,37 +34,35 @@ template <class _Iterator, class _DifferenceType>
_LIBCPP_HIDE_FROM_ABI void
__omp_map_to([[maybe_unused]] const _Iterator __p, [[maybe_unused]] const _DifferenceType __len) noexcept {
static_assert(__libcpp_is_contiguous_iterator<_Iterator>::value);
-# pragma omp target enter data map(to : __p [0:__len])
+# pragma omp target enter data map(to : __p[0 : __len])
}
template <class _Iterator, class _DifferenceType>
_LIBCPP_HIDE_FROM_ABI void
__omp_map_from([[maybe_unused]] const _Iterator __p, [[maybe_unused]] const _DifferenceType __len) noexcept {
static_assert(__libcpp_is_contiguous_iterator<_Iterator>::value);
-# pragma omp target exit data map(from : __p [0:__len])
+# pragma omp target exit data map(from : __p[0 : __len])
}
template <class _Iterator, class _DifferenceType>
_LIBCPP_HIDE_FROM_ABI void
__omp_map_alloc([[maybe_unused]] const _Iterator __p, [[maybe_unused]] const _DifferenceType __len) noexcept {
static_assert(__libcpp_is_contiguous_iterator<_Iterator>::value);
-# pragma omp target enter data map(alloc : __p [0:__len])
+# pragma omp target enter data map(alloc : __p[0 : __len])
}
template <class _Iterator, class _DifferenceType>
_LIBCPP_HIDE_FROM_ABI void
__omp_map_release([[maybe_unused]] const _Iterator __p, [[maybe_unused]] const _DifferenceType __len) noexcept {
static_assert(__libcpp_is_contiguous_iterator<_Iterator>::value);
-# pragma omp target exit data map(release : __p [0:__len])
+# pragma omp target exit data map(release : __p[0 : __len])
}
-} // namespace __omp_gpu_backend
+} // namespace __omp_backend
} // namespace __par_backend
_LIBCPP_END_NAMESPACE_STD
#endif // !defined(_LIBCPP_HAS_NO_INCOMPLETE_PSTL) && && _LIBCPP_STD_VER >= 17
-_LIBCPP_POP_MACROS
-
#endif // _LIBCPP___ALGORITHM_PSTL_BACKENDS_OPENMP_BACKEND_OMP_OFFLOAD_H
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/transform.h b/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
index e1c5f54675b3870..eec6fb6fed82070 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/transform.h
@@ -12,6 +12,7 @@
#include <__algorithm/pstl_backends/cpu_backends/backend.h>
#include <__algorithm/pstl_backends/openmp/backend.h>
#include <__algorithm/transform.h>
+#include <__algorithm/unwrap_iter.h>
#include <__config>
#include <__iterator/concepts.h>
#include <__iterator/wrap_iter.h>
diff --git a/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h b/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h
index 1684c3d273b2239..a03dafabc8d3870 100644
--- a/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h
+++ b/libcxx/include/__algorithm/pstl_backends/openmp/transform_reduce.h
@@ -11,7 +11,9 @@
#include <__algorithm/pstl_backends/cpu_backends/backend.h>
#include <__algorithm/pstl_backends/openmp/backend.h>
+#include <__algorithm/unwrap_iter.h>
#include <__config>
+#include <__functional/operations.h>
#include <__iterator/concepts.h>
#include <__iterator/wrap_iter.h>
#include <__numeric/transform_reduce.h>
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