Merging r345838:

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r345838 | erichkeane | 2018-11-01 08:11:41 -0700 (Thu, 01 Nov 2018) | 8 lines

CPU-Dispatch- Fix type of a member function, prevent deferrals

The member type creation for a cpu-dispatch function was not correctly
including the 'this' parameter, so ensure that the type is properly
determined. Also, disable defer in the cases of emitting the functoins,
as it can end up resulting in the wrong version being emitted.

Change-Id: I0b8fc5e0b0d1ae1a9d98fd54f35f27f6e5d5d083
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llvm-svn: 348684

Author: tstellar

clang/lib/CodeGen/CodeGenModule.cpp

@@ -2467,7 +2467,13 @@ void CodeGenModule::emitCPUDispatchDefinition(GlobalDecl GD) {
   assert(FD && "Not a FunctionDecl?");
   const auto *DD = FD->getAttr<CPUDispatchAttr>();
   assert(DD && "Not a cpu_dispatch Function?");
-  llvm::Type *DeclTy = getTypes().ConvertTypeForMem(FD->getType());
+  QualType CanonTy = Context.getCanonicalType(FD->getType());
+  llvm::Type *DeclTy = getTypes().ConvertFunctionType(CanonTy, FD);
+
+  if (const auto *CXXFD = dyn_cast<CXXMethodDecl>(FD)) {
+    const CGFunctionInfo &FInfo = getTypes().arrangeCXXMethodDeclaration(CXXFD);
+    DeclTy = getTypes().GetFunctionType(FInfo);
+  }
 
   StringRef ResolverName = getMangledName(GD);
   llvm::Type *ResolverType = llvm::FunctionType::get(
@@ -2485,7 +2491,7 @@ void CodeGenModule::emitCPUDispatchDefinition(GlobalDecl GD) {
     std::string MangledName = getMangledNameImpl(*this, GD, FD, true) +
                               getCPUSpecificMangling(*this, II->getName());
     llvm::Constant *Func = GetOrCreateLLVMFunction(
-        MangledName, DeclTy, GD, /*ForVTable=*/false, /*DontDefer=*/false,
+        MangledName, DeclTy, GD, /*ForVTable=*/false, /*DontDefer=*/true,
         /*IsThunk=*/false, llvm::AttributeList(), ForDefinition);
     llvm::SmallVector<StringRef, 32> Features;
     Target.getCPUSpecificCPUDispatchFeatures(II->getName(), Features);

clang/test/CodeGenCXX/attr-cpuspecific.cpp

@@ -0,0 +1,17 @@
+// RUN: %clang_cc1 -triple x86_64-linux-gnu -emit-llvm -o - %s | FileCheck %s --check-prefixes=CHECK,LINUX
+
+struct S {
+  __attribute__((cpu_specific(atom)))
+  void Func(){}
+  __attribute__((cpu_dispatch(ivybridge,atom)))
+  void Func(){}
+};
+
+void foo() {
+  S s;
+  s.Func();
+}
+
+// LINUX: define void (%struct.S*)* @_ZN1S4FuncEv.resolver
+// LINUX: ret void (%struct.S*)* @_ZN1S4FuncEv.S
+// LINUX: ret void (%struct.S*)* @_ZN1S4FuncEv.O