r235398 - [cuda] Added support for CUDA built-in variables.
Artem Belevich
tra at google.com
Tue Apr 21 10:39:07 PDT 2015
Author: tra
Date: Tue Apr 21 12:39:06 2015
New Revision: 235398
URL: http://llvm.org/viewvc/llvm-project?rev=235398&view=rev
Log:
[cuda] Added support for CUDA built-in variables.
Added cuda_builtin_vars.h which implements built-in CUDA variables
using __declattr(property).
Fields of built-in variables (except for warpSize) are implemented
using __declattr(property) which replaces read/write of a member field
with a call to a getter/setter member function, in this case with
appropriate NVPTX builtin.
Added a test case to check diagnostics on attempt to construct or
improperly access a built-in variable.
Differential Revision: http://reviews.llvm.org/D9064
Added:
cfe/trunk/lib/Headers/cuda/
cfe/trunk/lib/Headers/cuda/cuda_builtin_vars.h
cfe/trunk/test/CodeGenCUDA/cuda-builtin-vars.cu
cfe/trunk/test/SemaCUDA/cuda-builtin-vars.cu
Modified:
cfe/trunk/lib/Headers/CMakeLists.txt
Modified: cfe/trunk/lib/Headers/CMakeLists.txt
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Headers/CMakeLists.txt?rev=235398&r1=235397&r2=235398&view=diff
==============================================================================
--- cfe/trunk/lib/Headers/CMakeLists.txt (original)
+++ cfe/trunk/lib/Headers/CMakeLists.txt Tue Apr 21 12:39:06 2015
@@ -13,6 +13,7 @@ set(files
bmi2intrin.h
bmiintrin.h
cpuid.h
+ cuda/cuda_builtin_vars.h
emmintrin.h
f16cintrin.h
float.h
Added: cfe/trunk/lib/Headers/cuda/cuda_builtin_vars.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Headers/cuda/cuda_builtin_vars.h?rev=235398&view=auto
==============================================================================
--- cfe/trunk/lib/Headers/cuda/cuda_builtin_vars.h (added)
+++ cfe/trunk/lib/Headers/cuda/cuda_builtin_vars.h Tue Apr 21 12:39:06 2015
@@ -0,0 +1,110 @@
+/*===---- cuda_builtin_vars.h - CUDA built-in variables ---------------------===
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ *
+ *===-----------------------------------------------------------------------===
+ */
+
+#ifndef __CUDA_BUILTIN_VARS_H
+#define __CUDA_BUILTIN_VARS_H
+
+// The file implements built-in CUDA variables using __declspec(property).
+// https://msdn.microsoft.com/en-us/library/yhfk0thd.aspx
+// All read accesses of built-in variable fields get converted into calls to a
+// getter function which in turn would call appropriate builtin to fetch the
+// value.
+//
+// Example:
+// int x = threadIdx.x;
+// IR output:
+// %0 = call i32 @llvm.ptx.read.tid.x() #3
+// PTX output:
+// mov.u32 %r2, %tid.x;
+
+#define __CUDA_DEVICE_BUILTIN(FIELD, INTRINSIC) \
+ __declspec(property(get = __fetch_builtin_##FIELD)) unsigned int FIELD; \
+ static inline __attribute__((always_inline)) \
+ __attribute__((device)) unsigned int __fetch_builtin_##FIELD(void) { \
+ return INTRINSIC; \
+ }
+
+#if __cplusplus >= 201103L
+#define __DELETE =delete
+#else
+#define __DELETE
+#endif
+
+// Make sure nobody can create instances of the special varible types. nvcc
+// also disallows taking address of special variables, so we disable address-of
+// operator as well.
+#define __CUDA_DISALLOW_BUILTINVAR_ACCESS(TypeName) \
+ __attribute__((device)) TypeName() __DELETE; \
+ __attribute__((device)) TypeName(const TypeName &) __DELETE; \
+ __attribute__((device)) void operator=(const TypeName &) const __DELETE; \
+ __attribute__((device)) TypeName *operator&() const __DELETE
+
+struct __cuda_builtin_threadIdx_t {
+ __CUDA_DEVICE_BUILTIN(x,__builtin_ptx_read_tid_x());
+ __CUDA_DEVICE_BUILTIN(y,__builtin_ptx_read_tid_y());
+ __CUDA_DEVICE_BUILTIN(z,__builtin_ptx_read_tid_z());
+private:
+ __CUDA_DISALLOW_BUILTINVAR_ACCESS(__cuda_builtin_threadIdx_t);
+};
+
+struct __cuda_builtin_blockIdx_t {
+ __CUDA_DEVICE_BUILTIN(x,__builtin_ptx_read_ctaid_x());
+ __CUDA_DEVICE_BUILTIN(y,__builtin_ptx_read_ctaid_y());
+ __CUDA_DEVICE_BUILTIN(z,__builtin_ptx_read_ctaid_z());
+private:
+ __CUDA_DISALLOW_BUILTINVAR_ACCESS(__cuda_builtin_blockIdx_t);
+};
+
+struct __cuda_builtin_blockDim_t {
+ __CUDA_DEVICE_BUILTIN(x,__builtin_ptx_read_ntid_x());
+ __CUDA_DEVICE_BUILTIN(y,__builtin_ptx_read_ntid_y());
+ __CUDA_DEVICE_BUILTIN(z,__builtin_ptx_read_ntid_z());
+private:
+ __CUDA_DISALLOW_BUILTINVAR_ACCESS(__cuda_builtin_blockDim_t);
+};
+
+struct __cuda_builtin_gridDim_t {
+ __CUDA_DEVICE_BUILTIN(x,__builtin_ptx_read_nctaid_x());
+ __CUDA_DEVICE_BUILTIN(y,__builtin_ptx_read_nctaid_y());
+ __CUDA_DEVICE_BUILTIN(z,__builtin_ptx_read_nctaid_z());
+private:
+ __CUDA_DISALLOW_BUILTINVAR_ACCESS(__cuda_builtin_gridDim_t);
+};
+
+#define __CUDA_BUILTIN_VAR \
+ extern const __attribute__((device)) __attribute__((weak))
+__CUDA_BUILTIN_VAR __cuda_builtin_threadIdx_t threadIdx;
+__CUDA_BUILTIN_VAR __cuda_builtin_blockIdx_t blockIdx;
+__CUDA_BUILTIN_VAR __cuda_builtin_blockDim_t blockDim;
+__CUDA_BUILTIN_VAR __cuda_builtin_gridDim_t gridDim;
+
+// warpSize should translate to read of %WARP_SZ but there's currently no
+// builtin to do so. According to PTX v4.2 docs 'to date, all target
+// architectures have a WARP_SZ value of 32'.
+__attribute__((device)) const int warpSize = 32;
+
+#undef __CUDA_DEVICE_BUILTIN
+#undef __CUDA_BUILTIN_VAR
+#undef __CUDA_DISALLOW_BUILTINVAR_ACCESS
+
+#endif /* __CUDA_BUILTIN_VARS_H */
Added: cfe/trunk/test/CodeGenCUDA/cuda-builtin-vars.cu
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCUDA/cuda-builtin-vars.cu?rev=235398&view=auto
==============================================================================
--- cfe/trunk/test/CodeGenCUDA/cuda-builtin-vars.cu (added)
+++ cfe/trunk/test/CodeGenCUDA/cuda-builtin-vars.cu Tue Apr 21 12:39:06 2015
@@ -0,0 +1,28 @@
+// RUN: %clang_cc1 "-triple" "nvptx-nvidia-cuda" -emit-llvm -fcuda-is-device -o - %s | FileCheck %s
+
+#include "cuda/cuda_builtin_vars.h"
+
+// CHECK: define void @_Z6kernelPi(i32* %out)
+__attribute__((global))
+void kernel(int *out) {
+ int i = 0;
+ out[i++] = threadIdx.x; // CHECK: call i32 @llvm.ptx.read.tid.x()
+ out[i++] = threadIdx.y; // CHECK: call i32 @llvm.ptx.read.tid.y()
+ out[i++] = threadIdx.z; // CHECK: call i32 @llvm.ptx.read.tid.z()
+
+ out[i++] = blockIdx.x; // CHECK: call i32 @llvm.ptx.read.ctaid.x()
+ out[i++] = blockIdx.y; // CHECK: call i32 @llvm.ptx.read.ctaid.y()
+ out[i++] = blockIdx.z; // CHECK: call i32 @llvm.ptx.read.ctaid.z()
+
+ out[i++] = blockDim.x; // CHECK: call i32 @llvm.ptx.read.ntid.x()
+ out[i++] = blockDim.y; // CHECK: call i32 @llvm.ptx.read.ntid.y()
+ out[i++] = blockDim.z; // CHECK: call i32 @llvm.ptx.read.ntid.z()
+
+ out[i++] = gridDim.x; // CHECK: call i32 @llvm.ptx.read.nctaid.x()
+ out[i++] = gridDim.y; // CHECK: call i32 @llvm.ptx.read.nctaid.y()
+ out[i++] = gridDim.z; // CHECK: call i32 @llvm.ptx.read.nctaid.z()
+
+ out[i++] = warpSize; // CHECK: store i32 32,
+
+ // CHECK: ret void
+}
Added: cfe/trunk/test/SemaCUDA/cuda-builtin-vars.cu
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCUDA/cuda-builtin-vars.cu?rev=235398&view=auto
==============================================================================
--- cfe/trunk/test/SemaCUDA/cuda-builtin-vars.cu (added)
+++ cfe/trunk/test/SemaCUDA/cuda-builtin-vars.cu Tue Apr 21 12:39:06 2015
@@ -0,0 +1,57 @@
+// RUN: %clang_cc1 "-triple" "nvptx-nvidia-cuda" -fcuda-is-device -fsyntax-only -verify %s
+
+#include "cuda/cuda_builtin_vars.h"
+__attribute__((global))
+void kernel(int *out) {
+ int i = 0;
+ out[i++] = threadIdx.x;
+ threadIdx.x = 0; // expected-error {{no setter defined for property 'x'}}
+ out[i++] = threadIdx.y;
+ threadIdx.y = 0; // expected-error {{no setter defined for property 'y'}}
+ out[i++] = threadIdx.z;
+ threadIdx.z = 0; // expected-error {{no setter defined for property 'z'}}
+
+ out[i++] = blockIdx.x;
+ blockIdx.x = 0; // expected-error {{no setter defined for property 'x'}}
+ out[i++] = blockIdx.y;
+ blockIdx.y = 0; // expected-error {{no setter defined for property 'y'}}
+ out[i++] = blockIdx.z;
+ blockIdx.z = 0; // expected-error {{no setter defined for property 'z'}}
+
+ out[i++] = blockDim.x;
+ blockDim.x = 0; // expected-error {{no setter defined for property 'x'}}
+ out[i++] = blockDim.y;
+ blockDim.y = 0; // expected-error {{no setter defined for property 'y'}}
+ out[i++] = blockDim.z;
+ blockDim.z = 0; // expected-error {{no setter defined for property 'z'}}
+
+ out[i++] = gridDim.x;
+ gridDim.x = 0; // expected-error {{no setter defined for property 'x'}}
+ out[i++] = gridDim.y;
+ gridDim.y = 0; // expected-error {{no setter defined for property 'y'}}
+ out[i++] = gridDim.z;
+ gridDim.z = 0; // expected-error {{no setter defined for property 'z'}}
+
+ out[i++] = warpSize;
+ warpSize = 0; // expected-error {{cannot assign to variable 'warpSize' with const-qualified type 'const int'}}
+ // expected-note at cuda/cuda_builtin_vars.h:104 {{variable 'warpSize' declared const here}}
+
+ // Make sure we can't construct or assign to the special variables.
+ __cuda_builtin_threadIdx_t x; // expected-error {{calling a private constructor of class '__cuda_builtin_threadIdx_t'}}
+ // expected-note at cuda/cuda_builtin_vars.h:67 {{declared private here}}
+
+ __cuda_builtin_threadIdx_t y = threadIdx; // expected-error {{calling a private constructor of class '__cuda_builtin_threadIdx_t'}}
+ // expected-note at cuda/cuda_builtin_vars.h:67 {{declared private here}}
+
+ threadIdx = threadIdx; // expected-error {{'operator=' is a private member of '__cuda_builtin_threadIdx_t'}}
+ // expected-note at cuda/cuda_builtin_vars.h:67 {{declared private here}}
+
+ void *ptr = &threadIdx; // expected-error {{'operator&' is a private member of '__cuda_builtin_threadIdx_t'}}
+ // expected-note at cuda/cuda_builtin_vars.h:67 {{declared private here}}
+
+ // Following line should've caused an error as one is not allowed to
+ // take address of a built-in variable in CUDA. Alas there's no way
+ // to prevent getting address of a 'const int', so the line
+ // currently compiles without errors or warnings.
+ const void *wsptr = &warpSize;
+}
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