[SCM] libav/experimental: Make horizontal mmx scaling code match C code.

[siretart at users.alioth.debian.org]

The following commit has been merged in the experimental branch:
commit ef423a661818f3c0d8206a2abbc65ff555cc0c67
Author: Michael Niedermayer <michaelni at gmx.at>
Date:   Sat Sep 13 02:18:12 2008 +0000

    Make horizontal mmx scaling code match C code.
    
    Originally committed as revision 27596 to svn://svn.mplayerhq.hu/mplayer/trunk/libswscale

diff --git a/libswscale/swscale_template.c b/libswscale/swscale_template.c
index 4bcb605..f78d1bb 100644
--- a/libswscale/swscale_template.c
+++ b/libswscale/swscale_template.c
@@ -2170,7 +2170,6 @@ static inline void RENAME(hScale)(int16_t *dst, int dstW, uint8_t *src, int srcW
         "push            %%"REG_b"              \n\t"
 #endif
         "pxor                %%mm7, %%mm7       \n\t"
-        "movq        "MANGLE(w02)", %%mm6       \n\t"
         "push           %%"REG_BP"              \n\t" // we use 7 regs here ...
         "mov             %%"REG_a", %%"REG_BP"  \n\t"
         ASMALIGN(4)
@@ -2185,10 +2184,11 @@ static inline void RENAME(hScale)(int16_t *dst, int dstW, uint8_t *src, int srcW
         "punpcklbw           %%mm7, %%mm2       \n\t"
         "pmaddwd             %%mm1, %%mm0       \n\t"
         "pmaddwd             %%mm2, %%mm3       \n\t"
-        "psrad                  $8, %%mm0       \n\t"
-        "psrad                  $8, %%mm3       \n\t"
-        "packssdw            %%mm3, %%mm0       \n\t"
-        "pmaddwd             %%mm6, %%mm0       \n\t"
+        "movq                %%mm0, %%mm4       \n\t"
+        "punpckldq           %%mm3, %%mm0       \n\t"
+        "punpckhdq           %%mm3, %%mm4       \n\t"
+        "paddd               %%mm4, %%mm0       \n\t"
+        "psrad                  $7, %%mm0       \n\t"
         "packssdw            %%mm0, %%mm0       \n\t"
         "movd                %%mm0, (%4, %%"REG_BP")    \n\t"
         "add                    $4, %%"REG_BP"  \n\t"
@@ -2216,7 +2216,6 @@ static inline void RENAME(hScale)(int16_t *dst, int dstW, uint8_t *src, int srcW
         "push             %%"REG_b"             \n\t"
 #endif
         "pxor                 %%mm7, %%mm7      \n\t"
-        "movq         "MANGLE(w02)", %%mm6      \n\t"
         "push            %%"REG_BP"             \n\t" // we use 7 regs here ...
         "mov              %%"REG_a", %%"REG_BP" \n\t"
         ASMALIGN(4)
@@ -2242,11 +2241,11 @@ static inline void RENAME(hScale)(int16_t *dst, int dstW, uint8_t *src, int srcW
         "pmaddwd              %%mm2, %%mm5      \n\t"
         "paddd                %%mm4, %%mm0      \n\t"
         "paddd                %%mm5, %%mm3      \n\t"
-
-        "psrad                   $8, %%mm0      \n\t"
-        "psrad                   $8, %%mm3      \n\t"
-        "packssdw             %%mm3, %%mm0      \n\t"
-        "pmaddwd              %%mm6, %%mm0      \n\t"
+        "movq                 %%mm0, %%mm4      \n\t"
+        "punpckldq            %%mm3, %%mm0      \n\t"
+        "punpckhdq            %%mm3, %%mm4      \n\t"
+        "paddd                %%mm4, %%mm0      \n\t"
+        "psrad                   $7, %%mm0      \n\t"
         "packssdw             %%mm0, %%mm0      \n\t"
         "movd                 %%mm0, (%4, %%"REG_BP")   \n\t"
         "add                     $4, %%"REG_BP" \n\t"
@@ -2272,7 +2271,6 @@ static inline void RENAME(hScale)(int16_t *dst, int dstW, uint8_t *src, int srcW
         dst-= counter/2;
         asm volatile(
         "pxor                  %%mm7, %%mm7     \n\t"
-        "movq          "MANGLE(w02)", %%mm6     \n\t"
         ASMALIGN(4)
         "1:                                     \n\t"
         "mov                      %2, %%"REG_c" \n\t"
@@ -2297,10 +2295,11 @@ static inline void RENAME(hScale)(int16_t *dst, int dstW, uint8_t *src, int srcW
         "cmp                      %4, %%"REG_c" \n\t"
         " jb                      2b            \n\t"
         "add                      %6, %1        \n\t"
-        "psrad                    $8, %%mm4     \n\t"
-        "psrad                    $8, %%mm5     \n\t"
-        "packssdw              %%mm5, %%mm4     \n\t"
-        "pmaddwd               %%mm6, %%mm4     \n\t"
+        "movq                  %%mm4, %%mm0     \n\t"
+        "punpckldq             %%mm5, %%mm4     \n\t"
+        "punpckhdq             %%mm5, %%mm0     \n\t"
+        "paddd                 %%mm0, %%mm4     \n\t"
+        "psrad                    $7, %%mm4     \n\t"
         "packssdw              %%mm4, %%mm4     \n\t"
         "mov                      %3, %%"REG_a" \n\t"
         "movd                  %%mm4, (%%"REG_a", %0)   \n\t"

-- 
Libav/FFmpeg packaging