1 files changed, 15 insertions, 23 deletions
diff --git a/clang/lib/CodeGen/CodeGenFunction.cpp b/clang/lib/CodeGen/CodeGenFunction.cpp
index 5c8b882..e52c483 100644
--- a/clang/lib/CodeGen/CodeGenFunction.cpp
+++ b/clang/lib/CodeGen/CodeGenFunction.cpp
@@ -44,6 +44,7 @@
 #include "llvm/IR/MDBuilder.h"
 #include "llvm/IR/Operator.h"
 #include "llvm/Support/CRC.h"
+#include "llvm/Support/xxhash.h"
 #include "llvm/Transforms/Scalar/LowerExpectIntrinsic.h"
 #include "llvm/Transforms/Utils/PromoteMemToReg.h"
 #include <optional>
@@ -567,18 +568,16 @@ bool CodeGenFunction::AlwaysEmitXRayTypedEvents() const {
               XRayInstrKind::Typed);
 }
 
-llvm::Value *
-CodeGenFunction::DecodeAddrUsedInPrologue(llvm::Value *F,
-                                          llvm::Value *EncodedAddr) {
-  // Reconstruct the address of the global.
-  auto *PCRelAsInt = Builder.CreateSExt(EncodedAddr, IntPtrTy);
-  auto *FuncAsInt = Builder.CreatePtrToInt(F, IntPtrTy, "func_addr.int");
-  auto *GOTAsInt = Builder.CreateAdd(PCRelAsInt, FuncAsInt, "global_addr.int");
-  auto *GOTAddr = Builder.CreateIntToPtr(GOTAsInt, Int8PtrPtrTy, "global_addr");
-
-  // Load the original pointer through the global.
-  return Builder.CreateLoad(Address(GOTAddr, Int8PtrTy, getPointerAlign()),
-                            "decoded_addr");
+llvm::ConstantInt *
+CodeGenFunction::getUBSanFunctionTypeHash(QualType Ty) const {
+  // Remove any (C++17) exception specifications, to allow calling e.g. a
+  // noexcept function through a non-noexcept pointer.
+  auto ProtoTy = getContext().getFunctionTypeWithExceptionSpec(Ty, EST_None);
+  std::string Mangled;
+  llvm::raw_string_ostream Out(Mangled);
+  CGM.getCXXABI().getMangleContext().mangleTypeName(ProtoTy, Out, false);
+  return llvm::ConstantInt::get(CGM.Int32Ty,
+                                static_cast<uint32_t>(llvm::xxHash64(Mangled)));
 }
 
 void CodeGenFunction::EmitKernelMetadata(const FunctionDecl *FD,
@@ -948,19 +947,12 @@ void CodeGenFunction::StartFunction(GlobalDecl GD, QualType RetTy,
   // prologue data.
   if (FD && getLangOpts().CPlusPlus && SanOpts.has(SanitizerKind::Function)) {
     if (llvm::Constant *PrologueSig = getPrologueSignature(CGM, FD)) {
-      // Remove any (C++17) exception specifications, to allow calling e.g. a
-      // noexcept function through a non-noexcept pointer.
-      auto ProtoTy = getContext().getFunctionTypeWithExceptionSpec(
-          FD->getType(), EST_None);
-      llvm::Constant *FTRTTIConst =
-          CGM.GetAddrOfRTTIDescriptor(ProtoTy, /*ForEH=*/true);
-      llvm::GlobalVariable *FTRTTIProxy =
-          CGM.GetOrCreateRTTIProxyGlobalVariable(FTRTTIConst);
       llvm::LLVMContext &Ctx = Fn->getContext();
       llvm::MDBuilder MDB(Ctx);
-      Fn->setMetadata(llvm::LLVMContext::MD_func_sanitize,
-                      MDB.createRTTIPointerPrologue(PrologueSig, FTRTTIProxy));
-      CGM.addCompilerUsedGlobal(FTRTTIProxy);
+      Fn->setMetadata(
+          llvm::LLVMContext::MD_func_sanitize,
+          MDB.createRTTIPointerPrologue(
+              PrologueSig, getUBSanFunctionTypeHash(FD->getType())));
     }
   }