https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98612
andysem at mail dot ru changed:
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CC| |andysem at mail dot ru
--- Comment #9 from andysem at mail dot ru ---
Some relevant discussion here:
https://stackoverflow.com/questions/75818896/mm-comieq-ss-difference-between-clang-and-gcc
Indeed, the description for _mm_comieq_ss in the Intrinsics Guide 3.6.5 as of
2022-01-24 takes NaNs into account:
https://www.intel.com/content/www/us/en/docs/intrinsics-guide/index.html#text=comiss&ig_expand=1424
I think, the point that the intrinsic should correspond to the naked
instruction is not correct in this case. The intrinsic corresponds to the same
instruction either way, the question is only which flags are considered the
result of the intrinsic. And it seems that the intended behavior (as indicated
by the updated docs, icc and clang) is to check ZF & PF, not just ZF as gcc is
currently doing.
