[CIR] Upstream TBAA handling

[andykaylor]

Overview

Upstream support for generating TBAA attributes and lowering to TBAA metadata in LLVM IR.

We should carefully consider how we can reuse/share the classic codegen implementation for generating TBAA metadata.

Suggested minimal test case

// Compile with -O1
void test_int(int *a) {
  a = 1;
}

Existing incubator tests

clang/test/CIR/CodeGen/tbaa-bitinit.c
clang/test/CIR/CodeGen/tbaa-enum.c
clang/test/CIR/CodeGen/tbaa-enum.cpp
clang/test/CIR/CodeGen/tbaa-pointer.cpp
clang/test/CIR/CodeGen/tbaa-scalar.c
clang/test/CIR/CodeGen/tbaa-struct.cpp
clang/test/CIR/CodeGen/tbaa-union.cpp
clang/test/CIR/CodeGen/tbaa-vptr.cpp

[shashank1545]

I would like to work on this.

[HendrikHuebner]

@shashank1545 Hi, I was unaware of this issue and already opened a PR... #169226

Are you still working on this?

[andykaylor]

@shashank1545 I apologize. I didn't see the notification for your comment. Feel free to look at other open issues.

[shashank1545]

@HendrikHuebner I took up another task as i was not assigned this , so no issues .