GCC Code Coverage Report
Directory: ../../../ffmpeg/ Exec Total Coverage
File: src/libavcodec/x86/cabac.h Lines: 11 11 100.0 %
Date: 2020-10-23 17:01:47 Branches: 0 0 - %

Line Branch Exec Source
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/*
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 * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
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 *
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 * This file is part of FFmpeg.
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 *
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 * FFmpeg is free software; you can redistribute it and/or
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 * modify it under the terms of the GNU Lesser General Public
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 * License as published by the Free Software Foundation; either
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 * version 2.1 of the License, or (at your option) any later version.
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 *
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 * FFmpeg is distributed in the hope that it will be useful,
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 * but WITHOUT ANY WARRANTY; without even the implied warranty of
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 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 * Lesser General Public License for more details.
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 *
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 * You should have received a copy of the GNU Lesser General Public
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 * License along with FFmpeg; if not, write to the Free Software
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 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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 */
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#ifndef AVCODEC_X86_CABAC_H
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#define AVCODEC_X86_CABAC_H
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#include "libavcodec/cabac.h"
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#include "libavutil/attributes.h"
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#include "libavutil/macros.h"
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#include "libavutil/x86/asm.h"
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#include "config.h"
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#if   (defined(__i386) && defined(__clang__) && (__clang_major__<2 || (__clang_major__==2 && __clang_minor__<10)))\
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   || (                  !defined(__clang__) && defined(__llvm__) && __GNUC__==4 && __GNUC_MINOR__==2 && __GNUC_PATCHLEVEL__<=1)\
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   || (defined(__INTEL_COMPILER) && defined(_MSC_VER))
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#       define BROKEN_COMPILER 1
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#else
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#       define BROKEN_COMPILER 0
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#endif
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#if HAVE_INLINE_ASM
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#ifndef UNCHECKED_BITSTREAM_READER
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#define UNCHECKED_BITSTREAM_READER !CONFIG_SAFE_BITSTREAM_READER
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#endif
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#if UNCHECKED_BITSTREAM_READER
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#define END_CHECK(end) ""
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#else
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#define END_CHECK(end) \
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        "cmp    "end"       , %%"FF_REG_c"                              \n\t"\
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        "jge    1f                                                      \n\t"
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#endif
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#ifdef BROKEN_RELOCATIONS
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#define TABLES_ARG , "r"(tables)
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#if HAVE_FAST_CMOV
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#define BRANCHLESS_GET_CABAC_UPDATE(ret, retq, low, range, tmp) \
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        "cmp    "low"       , "tmp"                        \n\t"\
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        "cmova  %%ecx       , "range"                      \n\t"\
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        "sbb    %%rcx       , %%rcx                        \n\t"\
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        "and    %%ecx       , "tmp"                        \n\t"\
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        "xor    %%rcx       , "retq"                       \n\t"\
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        "sub    "tmp"       , "low"                        \n\t"
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#else /* HAVE_FAST_CMOV */
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#define BRANCHLESS_GET_CABAC_UPDATE(ret, retq, low, range, tmp) \
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/* P4 Prescott has crappy cmov,sbb,64-bit shift so avoid them */ \
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        "sub    "low"       , "tmp"                        \n\t"\
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        "sar    $31         , "tmp"                        \n\t"\
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        "sub    %%ecx       , "range"                      \n\t"\
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        "and    "tmp"       , "range"                      \n\t"\
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        "add    %%ecx       , "range"                      \n\t"\
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        "shl    $17         , %%ecx                        \n\t"\
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        "and    "tmp"       , %%ecx                        \n\t"\
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        "sub    %%ecx       , "low"                        \n\t"\
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        "xor    "tmp"       , "ret"                        \n\t"\
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        "movslq "ret"       , "retq"                       \n\t"
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#endif /* HAVE_FAST_CMOV */
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#define BRANCHLESS_GET_CABAC(ret, retq, statep, low, lowword, range, rangeq, tmp, tmpbyte, byte, end, norm_off, lps_off, mlps_off, tables) \
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        "movzbl "statep"    , "ret"                                     \n\t"\
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        "mov    "range"     , "tmp"                                     \n\t"\
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        "and    $0xC0       , "range"                                   \n\t"\
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        "lea    ("ret", "range", 2), %%ecx                              \n\t"\
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        "movzbl "lps_off"("tables", %%rcx), "range"                     \n\t"\
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        "sub    "range"     , "tmp"                                     \n\t"\
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        "mov    "tmp"       , %%ecx                                     \n\t"\
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        "shl    $17         , "tmp"                                     \n\t"\
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        BRANCHLESS_GET_CABAC_UPDATE(ret, retq, low, range, tmp)              \
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        "movzbl "norm_off"("tables", "rangeq"), %%ecx                   \n\t"\
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        "shl    %%cl        , "range"                                   \n\t"\
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        "movzbl "mlps_off"+128("tables", "retq"), "tmp"                 \n\t"\
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        "shl    %%cl        , "low"                                     \n\t"\
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        "mov    "tmpbyte"   , "statep"                                  \n\t"\
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        "test   "lowword"   , "lowword"                                 \n\t"\
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        "jnz    2f                                                      \n\t"\
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        "mov    "byte"      , %%"FF_REG_c"                              \n\t"\
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        END_CHECK(end)\
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        "add"FF_OPSIZE" $2  , "byte"                                    \n\t"\
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        "1:                                                             \n\t"\
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        "movzwl (%%"FF_REG_c") , "tmp"                                  \n\t"\
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        "lea    -1("low")   , %%ecx                                     \n\t"\
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        "xor    "low"       , %%ecx                                     \n\t"\
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        "shr    $15         , %%ecx                                     \n\t"\
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        "bswap  "tmp"                                                   \n\t"\
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        "shr    $15         , "tmp"                                     \n\t"\
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        "movzbl "norm_off"("tables", %%rcx), %%ecx                      \n\t"\
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        "sub    $0xFFFF     , "tmp"                                     \n\t"\
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        "neg    %%ecx                                                   \n\t"\
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        "add    $7          , %%ecx                                     \n\t"\
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        "shl    %%cl        , "tmp"                                     \n\t"\
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        "add    "tmp"       , "low"                                     \n\t"\
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        "2:                                                             \n\t"
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#else /* BROKEN_RELOCATIONS */
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#define TABLES_ARG NAMED_CONSTRAINTS_ARRAY_ADD(ff_h264_cabac_tables)
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#define RIP_ARG
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#if HAVE_FAST_CMOV
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#define BRANCHLESS_GET_CABAC_UPDATE(ret, low, range, tmp)\
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        "mov    "tmp"       , %%ecx     \n\t"\
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        "shl    $17         , "tmp"     \n\t"\
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        "cmp    "low"       , "tmp"     \n\t"\
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        "cmova  %%ecx       , "range"   \n\t"\
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        "sbb    %%ecx       , %%ecx     \n\t"\
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        "and    %%ecx       , "tmp"     \n\t"\
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        "xor    %%ecx       , "ret"     \n\t"\
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        "sub    "tmp"       , "low"     \n\t"
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#else /* HAVE_FAST_CMOV */
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#define BRANCHLESS_GET_CABAC_UPDATE(ret, low, range, tmp)\
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        "mov    "tmp"       , %%ecx     \n\t"\
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        "shl    $17         , "tmp"     \n\t"\
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        "sub    "low"       , "tmp"     \n\t"\
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        "sar    $31         , "tmp"     \n\t" /*lps_mask*/\
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        "sub    %%ecx       , "range"   \n\t" /*RangeLPS - range*/\
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        "and    "tmp"       , "range"   \n\t" /*(RangeLPS - range)&lps_mask*/\
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        "add    %%ecx       , "range"   \n\t" /*new range*/\
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        "shl    $17         , %%ecx     \n\t"\
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        "and    "tmp"       , %%ecx     \n\t"\
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        "sub    %%ecx       , "low"     \n\t"\
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        "xor    "tmp"       , "ret"     \n\t"
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#endif /* HAVE_FAST_CMOV */
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#define BRANCHLESS_GET_CABAC(ret, retq, statep, low, lowword, range, rangeq, tmp, tmpbyte, byte, end, norm_off, lps_off, mlps_off, tables) \
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        "movzbl "statep"    , "ret"                                     \n\t"\
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        "mov    "range"     , "tmp"                                     \n\t"\
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        "and    $0xC0       , "range"                                   \n\t"\
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        "movzbl "MANGLE(ff_h264_cabac_tables)"+"lps_off"("ret", "range", 2), "range" \n\t"\
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        "sub    "range"     , "tmp"                                     \n\t"\
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        BRANCHLESS_GET_CABAC_UPDATE(ret, low, range, tmp)                    \
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        "movzbl "MANGLE(ff_h264_cabac_tables)"+"norm_off"("range"), %%ecx    \n\t"\
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        "shl    %%cl        , "range"                                   \n\t"\
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        "movzbl "MANGLE(ff_h264_cabac_tables)"+"mlps_off"+128("ret"), "tmp"  \n\t"\
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        "shl    %%cl        , "low"                                     \n\t"\
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        "mov    "tmpbyte"   , "statep"                                  \n\t"\
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        "test   "lowword"   , "lowword"                                 \n\t"\
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        " jnz   2f                                                      \n\t"\
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        "mov    "byte"      , %%"FF_REG_c"                              \n\t"\
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        END_CHECK(end)\
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        "add"FF_OPSIZE" $2  , "byte"                                    \n\t"\
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        "1:                                                             \n\t"\
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        "movzwl (%%"FF_REG_c") , "tmp"                                  \n\t"\
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        "lea    -1("low")   , %%ecx                                     \n\t"\
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        "xor    "low"       , %%ecx                                     \n\t"\
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        "shr    $15         , %%ecx                                     \n\t"\
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        "bswap  "tmp"                                                   \n\t"\
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        "shr    $15         , "tmp"                                     \n\t"\
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        "movzbl "MANGLE(ff_h264_cabac_tables)"+"norm_off"(%%ecx), %%ecx \n\t"\
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        "sub    $0xFFFF     , "tmp"                                     \n\t"\
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        "neg    %%ecx                                                   \n\t"\
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        "add    $7          , %%ecx                                     \n\t"\
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        "shl    %%cl        , "tmp"                                     \n\t"\
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        "add    "tmp"       , "low"                                     \n\t"\
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        "2:                                                             \n\t"
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#endif /* BROKEN_RELOCATIONS */
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#if HAVE_7REGS && !BROKEN_COMPILER
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#define get_cabac_inline get_cabac_inline_x86
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1058373590
static av_always_inline int get_cabac_inline_x86(CABACContext *c,
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                                                 uint8_t *const state)
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{
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    int bit, tmp;
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#ifdef BROKEN_RELOCATIONS
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    void *tables;
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1058373590
    __asm__ volatile(
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        "lea    "MANGLE(ff_h264_cabac_tables)", %0      \n\t"
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        : "=&r"(tables)
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        : NAMED_CONSTRAINTS_ARRAY(ff_h264_cabac_tables)
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    );
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#endif
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1058373590
    __asm__ volatile(
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        BRANCHLESS_GET_CABAC("%0", "%q0", "(%4)", "%1", "%w1",
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                             "%2", "%q2", "%3", "%b3",
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                             "%c6(%5)", "%c7(%5)",
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                             AV_STRINGIFY(H264_NORM_SHIFT_OFFSET),
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                             AV_STRINGIFY(H264_LPS_RANGE_OFFSET),
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                             AV_STRINGIFY(H264_MLPS_STATE_OFFSET),
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                             "%8")
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        : "=&r"(bit), "=&r"(c->low), "=&r"(c->range), "=&q"(tmp)
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        : "r"(state), "r"(c),
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          "i"(offsetof(CABACContext, bytestream)),
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          "i"(offsetof(CABACContext, bytestream_end))
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          TABLES_ARG
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1058373590
          ,"1"(c->low), "2"(c->range)
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        : "%"FF_REG_c, "memory"
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    );
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1058373590
    return bit & 1;
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}
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#endif /* HAVE_7REGS && !BROKEN_COMPILER */
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#if !BROKEN_COMPILER
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#define get_cabac_bypass_sign get_cabac_bypass_sign_x86
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171893502
static av_always_inline int get_cabac_bypass_sign_x86(CABACContext *c, int val)
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{
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    x86_reg tmp;
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171893502
    __asm__ volatile(
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        "movl        %c6(%2), %k1       \n\t"
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        "movl        %c3(%2), %%eax     \n\t"
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        "shl             $17, %k1       \n\t"
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        "add           %%eax, %%eax     \n\t"
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        "sub             %k1, %%eax     \n\t"
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        "cdq                            \n\t"
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        "and           %%edx, %k1       \n\t"
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        "add             %k1, %%eax     \n\t"
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        "xor           %%edx, %%ecx     \n\t"
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        "sub           %%edx, %%ecx     \n\t"
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        "test           %%ax, %%ax      \n\t"
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        "jnz              1f            \n\t"
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        "mov         %c4(%2), %1        \n\t"
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        "subl        $0xFFFF, %%eax     \n\t"
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        "movzwl         (%1), %%edx     \n\t"
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        "bswap         %%edx            \n\t"
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        "shrl            $15, %%edx     \n\t"
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#if UNCHECKED_BITSTREAM_READER
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        "add              $2, %1        \n\t"
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        "addl          %%edx, %%eax     \n\t"
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        "mov              %1, %c4(%2)   \n\t"
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#else
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        "addl          %%edx, %%eax     \n\t"
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        "cmp         %c5(%2), %1        \n\t"
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        "jge              1f            \n\t"
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        "add"FF_OPSIZE"   $2, %c4(%2)   \n\t"
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#endif
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        "1:                             \n\t"
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        "movl          %%eax, %c3(%2)   \n\t"
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        : "+c"(val), "=&r"(tmp)
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        : "r"(c),
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          "i"(offsetof(CABACContext, low)),
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          "i"(offsetof(CABACContext, bytestream)),
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          "i"(offsetof(CABACContext, bytestream_end)),
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          "i"(offsetof(CABACContext, range))
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        : "%eax", "%edx", "memory"
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    );
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171893502
    return val;
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}
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#define get_cabac_bypass get_cabac_bypass_x86
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325040930
static av_always_inline int get_cabac_bypass_x86(CABACContext *c)
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{
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    x86_reg tmp;
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    int res;
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325040930
    __asm__ volatile(
265
        "movl        %c6(%2), %k1       \n\t"
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        "movl        %c3(%2), %%eax     \n\t"
267
        "shl             $17, %k1       \n\t"
268
        "add           %%eax, %%eax     \n\t"
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        "sub             %k1, %%eax     \n\t"
270
        "cdq                            \n\t"
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        "and           %%edx, %k1       \n\t"
272
        "add             %k1, %%eax     \n\t"
273
        "inc           %%edx            \n\t"
274
        "test           %%ax, %%ax      \n\t"
275
        "jnz              1f            \n\t"
276
        "mov         %c4(%2), %1        \n\t"
277
        "subl        $0xFFFF, %%eax     \n\t"
278
        "movzwl         (%1), %%ecx     \n\t"
279
        "bswap         %%ecx            \n\t"
280
        "shrl            $15, %%ecx     \n\t"
281
        "addl          %%ecx, %%eax     \n\t"
282
        "cmp         %c5(%2), %1        \n\t"
283
        "jge              1f            \n\t"
284
        "add"FF_OPSIZE"   $2, %c4(%2)   \n\t"
285
        "1:                             \n\t"
286
        "movl          %%eax, %c3(%2)   \n\t"
287
288
        : "=&d"(res), "=&r"(tmp)
289
        : "r"(c),
290
          "i"(offsetof(CABACContext, low)),
291
          "i"(offsetof(CABACContext, bytestream)),
292
          "i"(offsetof(CABACContext, bytestream_end)),
293
          "i"(offsetof(CABACContext, range))
294
        : "%eax", "%ecx", "memory"
295
    );
296
325040930
    return res;
297
}
298
#endif /* !BROKEN_COMPILER */
299
300
#endif /* HAVE_INLINE_ASM */
301
#endif /* AVCODEC_X86_CABAC_H */