[CUDA][HIP] Check calling convention based on function target

MSVC header files using vectorcall to differentiate overloaded functions, which
causes failure for AMDGPU target. This is because clang does not check function
calling convention based on function target.

This patch checks calling convention using the proper target info.

Differential Revision: https://reviews.llvm.org/D57716

llvm-svn: 354929

Author: yxsamliu

Diff for: clang/lib/Sema/SemaDeclAttr.cpp

@@ -4615,8 +4615,36 @@ bool Sema::CheckCallingConvAttr(const ParsedAttr &Attrs, CallingConv &CC,
   default: llvm_unreachable("unexpected attribute kind");
   }
 
+  TargetInfo::CallingConvCheckResult A = TargetInfo::CCCR_OK;
   const TargetInfo &TI = Context.getTargetInfo();
-  TargetInfo::CallingConvCheckResult A = TI.checkCallingConvention(CC);
+  auto *Aux = Context.getAuxTargetInfo();
+  if (LangOpts.CUDA) {
+    auto CudaTarget = IdentifyCUDATarget(FD);
+    bool CheckHost = false, CheckDevice = false;
+    switch (CudaTarget) {
+    case CFT_HostDevice:
+      CheckHost = true;
+      CheckDevice = true;
+      break;
+    case CFT_Host:
+      CheckHost = true;
+      break;
+    case CFT_Device:
+    case CFT_Global:
+      CheckDevice = true;
+      break;
+    case CFT_InvalidTarget:
+      llvm_unreachable("unexpected cuda target");
+    }
+    auto *HostTI = LangOpts.CUDAIsDevice ? Aux : &TI;
+    auto *DeviceTI = LangOpts.CUDAIsDevice ? &TI : Aux;
+    if (CheckHost && HostTI)
+      A = HostTI->checkCallingConvention(CC);
+    if (A == TargetInfo::CCCR_OK && CheckDevice && DeviceTI)
+      A = DeviceTI->checkCallingConvention(CC);
+  } else {
+    A = TI.checkCallingConvention(CC);
+  }
   if (A != TargetInfo::CCCR_OK) {
     if (A == TargetInfo::CCCR_Warning)
       Diag(Attrs.getLoc(), diag::warn_cconv_ignored) << Attrs;

Diff for: clang/test/SemaCUDA/amdgpu-windows-vectorcall.cu

@@ -0,0 +1,4 @@
+// RUN: %clang_cc1 -triple amdgcn-amd-amdhsa -aux-triple x86_64-pc-windows-msvc -fms-compatibility -fcuda-is-device -fsyntax-only -verify %s
+
+__cdecl void hostf1();
+__vectorcall void (*hostf2)() = hostf1; // expected-error {{cannot initialize a variable of type 'void ((*))() __attribute__((vectorcall))' with an lvalue of type 'void () __attribute__((cdecl))'}}