[FFmpeg-devel] [PATCH] avcodec: loongson fix optimized ff_sqrt bug

周晓勇 zhouxiaoyong at loongson.cn
Thu May 14 11:49:32 CEST 2015


>From a825fc8ad61d6296d12cc4074eda494e4b978fa3 Mon Sep 17 00:00:00 2001
From: ZhouXiaoyong <zhouxiaoyong at loongson.cn>
Date: Fri, 15 May 2015 01:30:42 +0800
Subject: [PATCH] avcodec: loongson fix optimized ff_sqrt bug

Signed-off-by: ZhouXiaoyong <zhouxiaoyong at loongson.cn>
---
 libavcodec/mips/mathops.h | 13 +++++--------
 1 file changed, 5 insertions(+), 8 deletions(-)

diff --git a/libavcodec/mips/mathops.h b/libavcodec/mips/mathops.h
index cdc7705..76a0f2d 100644
--- a/libavcodec/mips/mathops.h
+++ b/libavcodec/mips/mathops.h
@@ -76,15 +76,12 @@ static inline av_const int mid_pred(int a, int b, int c)
 #define ff_sqrt ff_sqrt
 static inline av_const unsigned int ff_sqrt(unsigned int a)
 {
-    unsigned int b;
+    float b;
+    __asm__ ("sqrt.s %0, %1     \n\t"
+             : "=f"(b)
+             : "f"((float)a));
 
-    __asm__ ("ctc1 %1, $f0      \n\t"
-             "sqrt.s $f2, $f0   \n\t"
-             "cvt.w.s $f0, $f2  \n\t"
-             "cfc1 %0, $f0      \n\t"
-             : "=r"(b)
-             : "r"(a));
-    return b;
+    return (unsigned int)b;
 }
 
 static inline av_const int64_t MAC64(int64_t d, int a, int b)
--
2.1.4



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