hans added inline comments.
================ Comment at: lib/Headers/x86intrin.h:49 +static __inline__ unsigned int __attribute__((__always_inline__, __nodebug__)) +__tzcnt_u32(unsigned int __X) { return __X ? __builtin_ctz(__X) : 32; } +#ifdef __x86_64__ ---------------- I'm worried about the conditional here. IIRC, ffmpeg uses TZCNT just as a faster encoding for BSF, but now we're putting a conditional in the way, so this will be slower actually. On the other hand, the alternative is weird too :-/ https://reviews.llvm.org/D26335 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits