| /** |
| * 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 FFmpeg. |
| * |
| * FFmpeg 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. |
| * |
| * FFmpeg 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 FFmpeg; 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_INLINE_ASM && HAVE_FAST_CMOV && HAVE_6REGS |
| #include "libavutil/attributes.h" |
| |
| #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 low = 1 + (((c->high - 1) * prob) >> 8); |
| unsigned int low_shift = low << 16; |
| int bit = 0; |
| c->code_word = code_word; |
| |
| __asm__( |
| "subl %4, %1 \n\t" |
| "subl %3, %2 \n\t" |
| "setae %b0 \n\t" |
| "cmovb %4, %1 \n\t" |
| "cmovb %5, %2 \n\t" |
| : "+q"(bit), "+&r"(c->high), "+&r"(c->code_word) |
| : "r"(low_shift), "r"(low), "r"(code_word) |
| ); |
| |
| return bit; |
| } |
| #endif |
| |
| #endif /* AVCODEC_X86_VP56_ARITH_H */ |
