[flang-commits] [flang] [flang][cuda] Add new entry points function for data transfer (PR #108244)

[Valentin Clement バレンタイン クレメン via flang-commits]

https://github.com/clementval created https://github.com/llvm/llvm-project/pull/108244

Add new entry points for more complex data transfer involving descriptors. These functions will be called when converting `cuf.data_transfer` operations. 

>From 968d2ddfdd648a2e34e53a9a662066688b7010c1 Mon Sep 17 00:00:00 2001
From: Valentin Clement <clementval at gmail.com>
Date: Mon, 9 Sep 2024 15:15:17 -0700
Subject: [PATCH] [flang][cuda] Add runtime function for data transfer

---
 flang/include/flang/Runtime/CUDA/memory.h | 45 +++++++++++++++++++++
 flang/lib/Optimizer/Dialect/FIRType.cpp   |  2 +-
 flang/runtime/CUDA/CMakeLists.txt         |  1 +
 flang/runtime/CUDA/memory.cpp             | 49 +++++++++++++++++++++++
 4 files changed, 96 insertions(+), 1 deletion(-)
 create mode 100644 flang/include/flang/Runtime/CUDA/memory.h
 create mode 100644 flang/runtime/CUDA/memory.cpp

diff --git a/flang/include/flang/Runtime/CUDA/memory.h b/flang/include/flang/Runtime/CUDA/memory.h
new file mode 100644
index 00000000000000..39fd333152eb8e
--- /dev/null
+++ b/flang/include/flang/Runtime/CUDA/memory.h
@@ -0,0 +1,45 @@
+//===-- include/flang/Runtime/CUDA/memory.h ---------------------*- C++ -*-===//
+//
+// 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 FORTRAN_RUNTIME_CUDA_MEMORY_H_
+#define FORTRAN_RUNTIME_CUDA_MEMORY_H_
+
+#include "flang/Runtime/descriptor.h"
+#include "flang/Runtime/entry-names.h"
+#include <cstddef>
+
+static constexpr unsigned kHostToDevice = 0;
+static constexpr unsigned kDeviceToHost = 1;
+static constexpr unsigned kDeviceToDevice = 2;
+
+namespace Fortran::runtime::cuda {
+
+extern "C" {
+
+// Set value to the data hold by a descriptor.
+void RTDECL(CUFMemsetDescriptor)(const Descriptor &desc, void* value,
+    const char *sourceFile = nullptr, int sourceLine = 0);
+
+// Data transfer from a pointer to a descriptor.
+void RTDECL(CUFDataTransferDescPtr)(const Descriptor &dst, void *src,
+    std::size_t bytes, unsigned mode, const char *sourceFile = nullptr,
+    int sourceLine = 0);
+
+// Data transfer from a descriptor to a pointer.
+void RTDECL(CUFDataTransferPtrDesc)(void *dst, const Descriptor &src,
+    std::size_t bytes, unsigned mode, const char *sourceFile = nullptr,
+    int sourceLine = 0);
+
+// Data transfer from a descriptor to a descriptor.
+void RTDECL(CUFDataTransferDescDesc)(const Descriptor &dst,
+    const Descriptor &src, unsigned mode, const char *sourceFile = nullptr,
+    int sourceLine = 0);
+
+} // extern "C"
+} // namespace Fortran::runtime::cuda
+#endif // FORTRAN_RUNTIME_CUDA_MEMORY_H_
diff --git a/flang/lib/Optimizer/Dialect/FIRType.cpp b/flang/lib/Optimizer/Dialect/FIRType.cpp
index c1debf28d00332..05f644654efe1b 100644
--- a/flang/lib/Optimizer/Dialect/FIRType.cpp
+++ b/flang/lib/Optimizer/Dialect/FIRType.cpp
@@ -1467,4 +1467,4 @@ fir::getTypeSizeAndAlignmentOrCrash(mlir::Location loc, mlir::Type ty,
   if (result)
     return *result;
   TODO(loc, "computing size of a component");
-}
\ No newline at end of file
+}
diff --git a/flang/runtime/CUDA/CMakeLists.txt b/flang/runtime/CUDA/CMakeLists.txt
index 81055b2737c0f1..490bb369b572f6 100644
--- a/flang/runtime/CUDA/CMakeLists.txt
+++ b/flang/runtime/CUDA/CMakeLists.txt
@@ -16,6 +16,7 @@ set(CUFRT_LIBNAME CufRuntime_cuda_${CUDAToolkit_VERSION_MAJOR})
 add_flang_library(${CUFRT_LIBNAME}
   allocator.cpp
   descriptor.cpp
+  memory.cpp
 )
 
 if (BUILD_SHARED_LIBS)
diff --git a/flang/runtime/CUDA/memory.cpp b/flang/runtime/CUDA/memory.cpp
new file mode 100644
index 00000000000000..34eee34762bec9
--- /dev/null
+++ b/flang/runtime/CUDA/memory.cpp
@@ -0,0 +1,49 @@
+//===-- runtime/CUDA/memory.cpp -------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+#include "flang/Runtime/CUDA/memory.h"
+#include "../terminator.h"
+
+#include "cuda_runtime.h"
+
+namespace Fortran::runtime::cuda {
+extern "C" {
+
+void RTDEF(CUFMemsetDescriptor)(const Descriptor &desc, void* value,
+    const char *sourceFile, int sourceLine) {
+  Terminator terminator{sourceFile, sourceLine};
+  terminator.Crash(
+      "not yet implemented: CUDA data transfer from a scalar value to a descriptor");
+}
+
+void RTDEF(CUFDataTransferDescPtr)(const Descriptor &desc, void *addr,
+    std::size_t bytes, unsigned mode, const char *sourceFile,
+    int sourceLine) {
+  Terminator terminator{sourceFile, sourceLine};
+  terminator.Crash(
+      "not yet implemented: CUDA data transfer from a pointer to a descriptor");
+}
+
+void RTDEF(CUFDataTransferPtrDesc)(void* addr, const Descriptor &desc,
+    std::size_t bytes, unsigned mode, const char *sourceFile,
+    int sourceLine) {
+  Terminator terminator{sourceFile, sourceLine};
+  terminator.Crash(
+      "not yet implemented: CUDA data transfer from a descriptor to a pointer");
+}
+
+void RTDECL(CUFDataTransferDescDesc)(const Descriptor &dstDesc,
+    const Descriptor &srcDesc, unsigned mode, const char *sourceFile,
+    int sourceLine) {
+  Terminator terminator{sourceFile, sourceLine};
+  terminator.Crash(
+      "not yet implemented: CUDA data transfer between two descriptors");
+}
+
+}
+} // namespace Fortran::runtime::cuda