c->code_word = bytestream_get_be16(&c->buffer);
}
-static av_always_inline void vp56_rac_renorm(VP56RangeCoder *c, unsigned int code_word)
+static av_always_inline unsigned int vp56_rac_renorm(VP56RangeCoder *c)
{
int shift = ff_h264_norm_shift[c->high] - 1;
int bits = c->bits;
+ unsigned int code_word = c->code_word;
c->high <<= shift;
code_word <<= shift;
bits -= 8;
}
c->bits = bits;
- c->code_word = code_word;
+ return code_word;
}
static inline int vp56_rac_get_prob(VP56RangeCoder *c, uint8_t prob)
{
/* Don't put c->high in a local variable; if we do that, gcc gets
* the stupids and turns the code below into a branch again. */
- unsigned int code_word = c->code_word;
+ unsigned int code_word = vp56_rac_renorm(c);
unsigned int low = 1 + (((c->high - 1) * prob) >> 8);
unsigned int low_shift = low << 8;
int bit = code_word >= low_shift;
* instead of branches -- faster, as this branch is basically
* unpredictable. */
c->high = bit ? c->high - low : low;
- code_word = bit ? code_word - low_shift : code_word;
+ c->code_word = bit ? code_word - low_shift : code_word;
- vp56_rac_renorm(c, code_word);
return bit;
}
static inline int vp56_rac_get(VP56RangeCoder *c)
{
+ unsigned int code_word = vp56_rac_renorm(c);
/* equiprobable */
int low = (c->high + 1) >> 1;
unsigned int low_shift = low << 8;
- int bit = c->code_word >= low_shift;
+ int bit = code_word >= low_shift;
if (bit) {
- c->high = (c->high - low) << 1;
- c->code_word -= low_shift;
+ c->high -= low;
+ code_word -= low_shift;
} else {
- c->high = low << 1;
+ c->high = low;
}
- /* normalize */
- c->code_word <<= 1;
- if (++c->bits == 0 && c->buffer < c->end) {
- c->bits = -8;
- c->code_word |= *c->buffer++;
- }
+ c->code_word = code_word;
return bit;
}