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put the code which is specific for the large crc table under #ifndef CONFIG_SMALL 

Originally committed as revision 5676 to svn://svn.ffmpeg.org/ffmpeg/trunk
This commit is contained in:
Michael Niedermayer 2006-07-08 20:23:19 +00:00
parent a29ff6b76b
commit a08d38ee82
1 changed files with 4 additions and 0 deletions
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4
libavutil/crc.c
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@ -33,10 +33,12 @@ int av_crc_init(AVCRC *ctx, int le, int bits, uint32_t poly, int ctx_size){
} }
} }
ctx[256]=1; ctx[256]=1;
#ifndef CONFIG_SMALL
if(ctx_size >= sizeof(AVCRC)*1024) if(ctx_size >= sizeof(AVCRC)*1024)
for (i = 0; i < 256; i++) for (i = 0; i < 256; i++)
for(j=0; j<3; j++) for(j=0; j<3; j++)
ctx[256*(j+1) + i]= (ctx[256*j + i]>>8) ^ ctx[ ctx[256*j + i]&0xFF ]; ctx[256*(j+1) + i]= (ctx[256*j + i]>>8) ^ ctx[ ctx[256*j + i]&0xFF ];
#endif
return 0; return 0;
} }
@ -44,6 +46,7 @@ int av_crc_init(AVCRC *ctx, int le, int bits, uint32_t poly, int ctx_size){
uint32_t av_crc(const AVCRC *ctx, uint32_t crc, const uint8_t *buffer, size_t length){ uint32_t av_crc(const AVCRC *ctx, uint32_t crc, const uint8_t *buffer, size_t length){
const uint8_t *end= buffer+length; const uint8_t *end= buffer+length;
#ifndef CONFIG_SMALL
if(!ctx[256]) if(!ctx[256])
while(buffer<end-3){ while(buffer<end-3){
crc ^= le2me_32(*(uint32_t*)buffer); buffer+=4; crc ^= le2me_32(*(uint32_t*)buffer); buffer+=4;
@ -52,6 +55,7 @@ uint32_t av_crc(const AVCRC *ctx, uint32_t crc, const uint8_t *buffer, size_t le
^ctx[1*256 + ((crc>>16)&0xFF)] ^ctx[1*256 + ((crc>>16)&0xFF)]
^ctx[0*256 + ((crc>>24) )]; ^ctx[0*256 + ((crc>>24) )];
} }
#endif
while(buffer<end) while(buffer<end)
crc = ctx[((uint8_t)crc) ^ *buffer++] ^ (crc >> 8); crc = ctx[((uint8_t)crc) ^ *buffer++] ^ (crc >> 8);