/** * VP5 and VP6 compatible video decoder (arith decoder) * * Copyright (C) 2006 Aurelien Jacobs <aurel@gnuage.org> * Copyright (C) 2010 Eli Friedman * * This file is part of Libav. * * Libav is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * Libav is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with Libav; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #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 */