[CUDA] Set LLVM calling convention for CUDA kernel

Some targets need special LLVM calling convention for CUDA kernel.
This patch does that through a TargetCodeGenInfo hook.

It only affects amdgcn target.

Patch by Greg Rodgers.
Revised and lit tests added by Yaxun Liu.

Differential Revision: https://reviews.llvm.org/D45223

llvm-svn: 330447

1 files changed, 41 insertions, 0 deletions

diff --git a/clang/test/CodeGenCUDA/kernel-amdgcn.cu b/clang/test/CodeGenCUDA/kernel-amdgcn.cu
new file mode 100644
index 00000000000..ffa6c9549f0
--- /dev/null
+++ b/clang/test/CodeGenCUDA/kernel-amdgcn.cu
@@ -0,0 +1,41 @@
+// RUN: %clang_cc1 -triple amdgcn -fcuda-is-device -emit-llvm %s -o - | FileCheck %s
+#include "Inputs/cuda.h"
+
+// CHECK: define amdgpu_kernel void @_ZN1A6kernelEv
+class A {
+public:
+  static __global__ void kernel(){}
+};
+
+// CHECK: define void @_Z10non_kernelv
+__device__ void non_kernel(){}
+
+// CHECK: define amdgpu_kernel void @_Z6kerneli
+__global__ void kernel(int x) {
+  non_kernel();
+}
+
+// CHECK: define amdgpu_kernel void @_Z11EmptyKernelIvEvv
+template <typename T>
+__global__ void EmptyKernel(void) {}
+
+struct Dummy {
+  /// Type definition of the EmptyKernel kernel entry point
+  typedef void (*EmptyKernelPtr)();
+  EmptyKernelPtr Empty() { return EmptyKernel<void>; } 
+};
+
+// CHECK: define amdgpu_kernel void @_Z15template_kernelI1AEvT_
+template<class T>
+__global__ void template_kernel(T x) {}
+
+void launch(void *f);
+
+int main() {
+  Dummy D;
+  launch((void*)A::kernel);
+  launch((void*)kernel);
+  launch((void*)template_kernel<A>);
+  launch((void*)D.Empty());
+  return 0;
+}