Revert "[MS][clang] Add support for vector deleting destructors (#126240)"

This caused link errors when building with sancov. See comment on the PR.

> Whereas it is UB in terms of the standard to delete an array of objects
> via pointer whose static type doesn't match its dynamic type, MSVC
> supports an extension allowing to do it.
> Aside from array deletion not working correctly in the mentioned case,
> currently not having this extension implemented causes clang to generate
> code that is not compatible with the code generated by MSVC, because
> clang always puts scalar deleting destructor to the vftable. This PR
> aims to resolve these problems.
>
> Fixes https://github.com/llvm/llvm-project/issues/19772

This reverts commit d6942d54f677000cf713d2b0eba57b641452beb4.

1 files changed, 0 insertions, 46 deletions

diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index 1f6321a..f88d620 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -7939,49 +7939,3 @@ void CodeGenModule::moveLazyEmissionStates(CodeGenModule *NewBuilder) {
 
   NewBuilder->ABI->MangleCtx = std::move(ABI->MangleCtx);
 }
-
-bool CodeGenModule::classNeedsVectorDestructor(const CXXRecordDecl *RD) {
-  CXXDestructorDecl *Dtor = RD->getDestructor();
-  // The compiler can't know if new[]/delete[] will be used outside of the DLL,
-  // so just force vector deleting destructor emission if dllexport is present.
-  // This matches MSVC behavior.
-  if (Dtor && Dtor->isVirtual() && Dtor->isDefined() &&
-      Dtor->hasAttr<DLLExportAttr>())
-    return true;
-
-  assert(getCXXABI().hasVectorDeletingDtors());
-  return RequireVectorDeletingDtor.count(RD);
-}
-
-void CodeGenModule::requireVectorDestructorDefinition(const CXXRecordDecl *RD) {
-  assert(getCXXABI().hasVectorDeletingDtors());
-  RequireVectorDeletingDtor.insert(RD);
-
-  // To reduce code size in general case we lazily emit scalar deleting
-  // destructor definition and an alias from vector deleting destructor to
-  // scalar deleting destructor. It may happen that we first emitted the scalar
-  // deleting destructor definition and the alias and then discovered that the
-  // definition of the vector deleting destructor is required. Then we need to
-  // remove the alias and the scalar deleting destructor and queue vector
-  // deleting destructor body for emission. Check if that is the case.
-  CXXDestructorDecl *DtorD = RD->getDestructor();
-  GlobalDecl ScalarDtorGD(DtorD, Dtor_Deleting);
-  StringRef MangledName = getMangledName(ScalarDtorGD);
-  llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
-  if (Entry && !Entry->isDeclaration()) {
-    GlobalDecl VectorDtorGD(DtorD, Dtor_VectorDeleting);
-    StringRef VDName = getMangledName(VectorDtorGD);
-    llvm::GlobalValue *VDEntry = GetGlobalValue(VDName);
-    // It exists and it should be an alias.
-    assert(VDEntry && isa<llvm::GlobalAlias>(VDEntry));
-    auto *NewFn = llvm::Function::Create(
-        cast<llvm::FunctionType>(VDEntry->getValueType()),
-        llvm::Function::ExternalLinkage, VDName, &getModule());
-    NewFn->takeName(VDEntry);
-    VDEntry->replaceAllUsesWith(NewFn);
-    VDEntry->eraseFromParent();
-    Entry->replaceAllUsesWith(NewFn);
-    Entry->eraseFromParent();
-    addDeferredDeclToEmit(VectorDtorGD);
-  }
-}