[PATCH] D127007: [MC] Add 'G' to augmentation string for MTE instrumented functions

Mon Jun 6 17:22:10 PDT 2022

fmayer added inline comments.

================
Comment at: llvm/lib/Target/AArch64/AArch64AsmPrinter.cpp:1289
+  case AArch64::EMITMTETAGGED: {
+    ExceptionHandling ExceptionHandlingType = MAI->getExceptionHandlingType();
+    if (ExceptionHandlingType != ExceptionHandling::DwarfCFI &&
----------------
eugenis wrote:
> As we've seen recently, sometimes even nounwind frames get unwound. Is it possible to relax some of these conditions to emit the "G" in as many cases as possible? This is the situation where MTE is more demanding to the unwind correctness, so I'd rather err on the safe side.
> 
I'm not sure. This is exactly the same logic as for the B-Key, so either we change both or neither. B-Key is just as important to correctness as this is.

What do you mean "nounwind frames get unwound"? AFAICT they do get skipped over, so the 'G' wouldn't help.

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D127007/new/

https://reviews.llvm.org/D127007