Commit 5e1fd413 authored by John Koleszar's avatar John Koleszar
Browse files

Speed up VP8DX_BOOL_DECODER_FILL

The end-of-buffer check is hoisted out of the inner loop. Gives
about 0.5% improvement on x86_64.

Change-Id: I8e3ed08af7d33468c5c749af36c2dfa19677f971
parent 9594370e
......@@ -51,19 +51,26 @@ void vp8dx_bool_decoder_fill(BOOL_DECODER *br);
#define VP8DX_BOOL_DECODER_FILL(_count,_value,_bufptr,_bufend) \
do \
{ \
int shift; \
for(shift = VP8_BD_VALUE_SIZE - 8 - ((_count) + 8); shift >= 0; ) \
int shift = VP8_BD_VALUE_SIZE - 8 - ((_count) + 8); \
int loop_end, x; \
size_t bits_left = ((_bufend)-(_bufptr))*CHAR_BIT; \
\
x = shift + CHAR_BIT - bits_left; \
loop_end = 0; \
if(x >= 0) \
{ \
if((_bufptr) >= (_bufend)) { \
(_count) += VP8_LOTS_OF_BITS; \
break; \
} \
(_count) += 8; \
(_count) += VP8_LOTS_OF_BITS; \
loop_end = x; \
if(!bits_left) break; \
} \
while(shift >= loop_end) \
{ \
(_count) += CHAR_BIT; \
(_value) |= (VP8_BD_VALUE)*(_bufptr)++ << shift; \
shift -= 8; \
shift -= CHAR_BIT; \
} \
} \
while(0)
while(0) \
static int vp8dx_decode_bool(BOOL_DECODER *br, int probability) {
......
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