[HIP] Add the interface deriving the stub name of device kernels.

Summary:
- Revise the interface to derive the stub name and simplify the
  assertion of it.

Reviewers: yaxunl, tra

Subscribers: cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D63335

llvm-svn: 363553
diff --git a/clang/lib/CodeGen/CGCUDANV.cpp b/clang/lib/CodeGen/CGCUDANV.cpp
index 42d2b15..25d6b8e 100644
--- a/clang/lib/CodeGen/CGCUDANV.cpp
+++ b/clang/lib/CodeGen/CGCUDANV.cpp
@@ -132,6 +132,8 @@
   llvm::Function *makeModuleCtorFunction() override;
   /// Creates module destructor function
   llvm::Function *makeModuleDtorFunction() override;
+  /// Construct and return the stub name of a kernel.
+  std::string getDeviceStubName(llvm::StringRef Name) const override;
 };
 
 }
@@ -217,10 +219,20 @@
 
 void CGNVCUDARuntime::emitDeviceStub(CodeGenFunction &CGF,
                                      FunctionArgList &Args) {
-  assert(getDeviceSideName(CGF.CurFuncDecl) == CGF.CurFn->getName() ||
-         getDeviceSideName(CGF.CurFuncDecl) + ".stub" == CGF.CurFn->getName() ||
-         CGF.CGM.getContext().getTargetInfo().getCXXABI() !=
-             CGF.CGM.getContext().getAuxTargetInfo()->getCXXABI());
+  // Ensure either we have different ABIs between host and device compilations,
+  // says host compilation following MSVC ABI but device compilation follows
+  // Itanium C++ ABI or, if they follow the same ABI, kernel names after
+  // mangling should be the same after name stubbing. The later checking is
+  // very important as the device kernel name being mangled in host-compilation
+  // is used to resolve the device binaries to be executed. Inconsistent naming
+  // result in undefined behavior. Even though we cannot check that naming
+  // directly between host- and device-compilations, the host- and
+  // device-mangling in host compilation could help catching certain ones.
+  assert((CGF.CGM.getContext().getAuxTargetInfo() &&
+          (CGF.CGM.getContext().getAuxTargetInfo()->getCXXABI() !=
+           CGF.CGM.getContext().getTargetInfo().getCXXABI())) ||
+         getDeviceStubName(getDeviceSideName(CGF.CurFuncDecl)) ==
+             CGF.CurFn->getName());
 
   EmittedKernels.push_back({CGF.CurFn, CGF.CurFuncDecl});
   if (CudaFeatureEnabled(CGM.getTarget().getSDKVersion(),
@@ -780,6 +792,12 @@
   return ModuleDtorFunc;
 }
 
+std::string CGNVCUDARuntime::getDeviceStubName(llvm::StringRef Name) const {
+  if (!CGM.getLangOpts().HIP)
+    return Name;
+  return std::move((Name + ".stub").str());
+}
+
 CGCUDARuntime *CodeGen::CreateNVCUDARuntime(CodeGenModule &CGM) {
   return new CGNVCUDARuntime(CGM);
 }