[clang] [llvm] [X86][MC] Added support for -msse2avx option in llvm-mc (PR #96860)

[Simon Pilgrim via cfe-commits]

RKSimon wrote:

> > How easy would it be to add an option for this to update inline asm? I'm not asking you to do this here, I just want to know if this approach would make it straightforward to add in the future.
> 
> Should we touch the inline asm? (GCC doesn't https://godbolt.org/z/o9MM9br95.

Definitely not be default, but I know of cases (old math libs with sse inline asm) that I'd like to build specific files/libs with this switched on to remove SSE-AVX stalls.

https://github.com/llvm/llvm-project/pull/96860