Revert "[Clang,debuginfo] added vtt parameter in destructor DISubroutineType (#130674)"

This reverts commit 27c1aa9b9cf9e0b14211758ff8f7d3aaba24ffcf.

See comments on PR. After this change, Clang now asserts like this:

clang: ../llvm/include/llvm/IR/Metadata.h:1435: const MDOperand &llvm::MDNode::getOperand(unsigned int) const: Assertion `I < getNumOperands() && "Out of range"' failed.
...
 #8 0x000055f345c4e4cb clang::CodeGen::CGDebugInfo::getOrCreateInstanceMethodType()
 #9 0x000055f345c5ba4f clang::CodeGen::CGDebugInfo::EmitFunctionDecl()
 #10 0x000055f345b52519 clang::CodeGen::CodeGenModule::EmitExternalFunctionDeclaration()

This is due to pre-existing jankiness in the way BPF emits extra
declarations for debug info, but we should rollback and then fix forward.

1 files changed, 12 insertions, 3 deletions

diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 83d8d4f..a073c5d 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -5837,15 +5837,24 @@ void CodeGenModule::EmitExternalVarDeclaration(const VarDecl *D) {
     }
 }
 
+static GlobalDecl getBaseVariantGlobalDecl(const FunctionDecl *FD) {
+  if (auto const *CD = dyn_cast<const CXXConstructorDecl>(FD))
+    return GlobalDecl(CD, CXXCtorType::Ctor_Base);
+  else if (auto const *DD = dyn_cast<const CXXDestructorDecl>(FD))
+    return GlobalDecl(DD, CXXDtorType::Dtor_Base);
+  return GlobalDecl(FD);
+}
+
 void CodeGenModule::EmitExternalFunctionDeclaration(const FunctionDecl *FD) {
   if (CGDebugInfo *DI = getModuleDebugInfo())
     if (getCodeGenOpts().hasReducedDebugInfo()) {
+      GlobalDecl GD = getBaseVariantGlobalDecl(FD);
       auto *Ty = getTypes().ConvertType(FD->getType());
-      StringRef MangledName = getMangledName(FD);
+      StringRef MangledName = getMangledName(GD);
       auto *Fn = cast<llvm::Function>(
-          GetOrCreateLLVMFunction(MangledName, Ty, FD, /* ForVTable */ false));
+          GetOrCreateLLVMFunction(MangledName, Ty, GD, /* ForVTable */ false));
       if (!Fn->getSubprogram())
-        DI->EmitFunctionDecl(FD, FD->getLocation(), FD->getType(), Fn);
+        DI->EmitFunctionDecl(GD, FD->getLocation(), FD->getType(), Fn);
     }
 }