According to a quick micro-benchmark, this new version is 20% faster on my Haswell laptop.
v2: Removed the XXX note about x86_64 from the comment v3: Use an intrinsic instead of an __asm__ block. This should give us MSVC support for free. Signed-off-by: Jason Ekstrand <jason.ekstr...@intel.com> --- src/mesa/main/imports.h | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/src/mesa/main/imports.h b/src/mesa/main/imports.h index af780b2..6eb84ca 100644 --- a/src/mesa/main/imports.h +++ b/src/mesa/main/imports.h @@ -274,10 +274,12 @@ static inline int IROUND_POS(float f) return (int) (f + 0.5F); } +#if defined(USE_X86_64_ASM) +# include <xmmintrin.h> +#endif /** * Convert float to int using a fast method. The rounding mode may vary. - * XXX We could use an x86-64/SSE2 version here. */ static inline int F_TO_I(float f) { @@ -292,6 +294,8 @@ static inline int F_TO_I(float f) fistp r } return r; +#elif defined(USE_X86_64_ASM) + return _mm_cvt_ss2si(_mm_load_ss(&f)); #else return IROUND(f); #endif -- 2.0.1 _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev