From 93a319f13ba94c783afe5eb832f4de8980e6baa5 Mon Sep 17 00:00:00 2001 From: Loren Merritt Date: Fri, 15 Sep 2006 00:36:49 +0000 Subject: [PATCH] asm implementation of mid_pred. 20% faster huffyuv decoding, 4% faster ffv1. Originally committed as revision 6254 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavutil/common.h | 17 ++++++++++++++++- 1 file changed, 16 insertions(+), 1 deletion(-) diff --git a/libavutil/common.h b/libavutil/common.h index 9d2d000..c9bdd56 100644 --- a/libavutil/common.h +++ b/libavutil/common.h @@ -235,7 +235,22 @@ static inline int av_log2_16bit(unsigned int v) /* median of 3 */ static inline int mid_pred(int a, int b, int c) { -#if 0 +#if (defined(ARCH_X86) && __CPU__ >= 686 || defined(ARCH_X86_64)) && !defined(RUNTIME_CPUDETECT) + int i=a, j=a; + asm volatile( + "cmp %4, %2 \n\t" + "cmovg %4, %0 \n\t" + "cmovl %4, %1 \n\t" + "cmp %4, %3 \n\t" + "cmovg %3, %0 \n\t" + "cmovl %3, %1 \n\t" + "cmp %3, %2 \n\t" + "cmovl %1, %0 \n\t" + :"+&r"(i), "+&r"(j) + :"r"(a), "r"(b), "r"(c) + ); + return i; +#elif 0 int t= (a-b)&((a-b)>>31); a-=t; b+=t; -- 2.7.4