[PATCH] D45616: [X86] Lower _mm[256|512]_cmp[.]_mask intrinsics to native llvm IR

2018-11-07 Thread Nikita Astafev via Phabricator via cfe-commits
nastafev added a comment. Hello. It seems you were well aware that you are changing the semantics of FP operation here by ignoring the signaling/quiet portion of the immediate. But what shall the user do now? There was no way to force quiet FP comparison behavior in C language, so intrinsics an

[PATCH] D45616: [X86] Lower _mm[256|512]_cmp[.]_mask intrinsics to native llvm IR

2018-11-07 Thread Nikita Astafev via Phabricator via cfe-commits
nastafev added a comment. > can trigger arbitrary floating-point exceptions anywhere in your code I believe this statement reflects the current state of many compilers on the market, I guess I just don't see the reason why making things worse. It seems the original intent of the commit was to

[PATCH] D45616: [X86] Lower _mm[256|512]_cmp[.]_mask intrinsics to native llvm IR

2018-11-08 Thread Nikita Astafev via Phabricator via cfe-commits
nastafev added a comment. Thanks, I agree with @andrew.w.kaylor and his interpretation. I was trying to convey the message that the programmer operating with intrinsics relies on the semantics they carry because there's no other way to express that semantics. Re-optimizing what's already optimiz