[PATCH] D28304: [compiler-rt] [cmake] Disable appending -msse* flags implicitly

[Dmitry Vyukov via Phabricator via cfe-commits]

dvyukov added a comment.

Yes, for tsan runtime detection does not make lots of sense -- we only have few SSE instructions on inlined fast path. The SSE code provides quite substantial speedup. User -march flag won't help as runtime is prebuilt. SCUDO is sse4.2, but tsan is sse3. Do you actually see any problems with sse3? It's like 10 years old. I agree with you that strictly speaking we do wrong thing for old processors. But if we disable it, we disable it for everybody.  So if you don't hit cashes with it, I would prefer to keep sse3 in tsan.


https://reviews.llvm.org/D28304