libavcodec/x86/vp56_arith.h

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#ifndef AVCODEC_X86_VP56_ARITH_H
#define AVCODEC_X86_VP56_ARITH_H

#if HAVE_FAST_CMOV
#define vp56_rac_get_prob vp56_rac_get_prob
static av_always_inline int vp56_rac_get_prob(VP56RangeCoder *c, uint8_t prob)
{
    unsigned int code_word = vp56_rac_renorm(c);
    unsigned int high = c->high;
    unsigned int low = 1 + (((high - 1) * prob) >> 8);
    unsigned int low_shift = low << 16;
    int bit = 0;

    __asm__(
        "subl  %4, %1      \n\t"
        "subl  %3, %2      \n\t"
        "leal (%2, %3), %3 \n\t"
        "setae %b0         \n\t"
        "cmovb %4, %1      \n\t"
        "cmovb %3, %2      \n\t"
        : "+q"(bit), "+r"(high), "+r"(code_word), "+r"(low_shift)
        : "r"(low)
    );

    c->high      = high;
    c->code_word = code_word;
    return bit;
}
#endif

#endif /* AVCODEC_X86_VP56_ARITH_H */

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