From 6510f43cf3e06cb3dae4a501fb80fe59d085b4b5 Mon Sep 17 00:00:00 2001
From: Michael Niedermayer <michaelni@gmx.at>
Date: Wed, 1 Jun 2005 11:56:58 +0000
Subject: [PATCH] merge a few asm blocks so gcc cant unoptimize it (658->631
dezicycles on duron)
Originally committed as revision 4334 to svn://svn.ffmpeg.org/ffmpeg/trunk
---
libavcodec/i386/idct_mmx.c | 20 +++++++++++++-------
1 file changed, 13 insertions(+), 7 deletions(-)
diff --git a/libavcodec/i386/idct_mmx.c b/libavcodec/i386/idct_mmx.c
index c2bd6c88a13..7be3cf592bf 100644
--- a/libavcodec/i386/idct_mmx.c
+++ b/libavcodec/i386/idct_mmx.c
@@ -637,14 +637,13 @@ declare_idct (ff_mmx_idct, mmx_table,
SBUTTERFLY( a, c, d, dq ) /* a=aeim d=bfjn */\
SBUTTERFLY( t, b, c, dq ) /* t=cgko c=dhlp */
-#define STORE_DIFF_4P( p, t, z, dst ) \
- asm volatile(\
+#define STORE_DIFF_4P( p, t, z ) \
"psraw $6, "#p" \n\t"\
"movd (%0), "#t" \n\t"\
"punpcklbw "#z", "#t" \n\t"\
"paddsw "#t", "#p" \n\t"\
"packuswb "#z", "#p" \n\t"\
- "movd "#p", (%0) \n\t" :: "r"(dst) )
+ "movd "#p", (%0) \n\t"
static const uint64_t ff_pw_32 attribute_used __attribute__ ((aligned(8))) = 0x0020002000200020ULL;
@@ -674,8 +673,15 @@ void ff_h264_idct_add_mmx2(uint8_t *dst, int16_t *block, int stride)
"pxor %%mm7, %%mm7 \n\t"
:: "m"(ff_pw_32));
- STORE_DIFF_4P( %%mm0, %%mm1, %%mm7, &dst[0*stride] );
- STORE_DIFF_4P( %%mm2, %%mm1, %%mm7, &dst[1*stride] );
- STORE_DIFF_4P( %%mm3, %%mm1, %%mm7, &dst[2*stride] );
- STORE_DIFF_4P( %%mm4, %%mm1, %%mm7, &dst[3*stride] );
+ asm volatile(
+ STORE_DIFF_4P( %%mm0, %%mm1, %%mm7)
+ "addl %1, %0 \n\t"
+ STORE_DIFF_4P( %%mm2, %%mm1, %%mm7)
+ "addl %1, %0 \n\t"
+ STORE_DIFF_4P( %%mm3, %%mm1, %%mm7)
+ "addl %1, %0 \n\t"
+ STORE_DIFF_4P( %%mm4, %%mm1, %%mm7)
+ : "+r"(dst)
+ : "r" (stride)
+ );
}
--
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