1/* 2 * This file is part of FFmpeg. 3 * 4 * FFmpeg is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU Lesser General Public 6 * License as published by the Free Software Foundation; either 7 * version 2.1 of the License, or (at your option) any later version. 8 * 9 * FFmpeg is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 * Lesser General Public License for more details. 13 * 14 * You should have received a copy of the GNU Lesser General Public 15 * License along with FFmpeg; if not, write to the Free Software 16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 17 */ 18 19#ifndef AVCODEC_AARCH64_CABAC_H 20#define AVCODEC_AARCH64_CABAC_H 21 22#include "config.h" 23#if HAVE_INLINE_ASM 24 25#include "libavutil/attributes.h" 26#include "libavutil/internal.h" 27#include "libavcodec/cabac.h" 28 29#define get_cabac_inline get_cabac_inline_aarch64 30static av_always_inline int get_cabac_inline_aarch64(CABACContext *c, 31 uint8_t *const state) 32{ 33 int bit; 34 void *reg_a, *reg_b, *reg_c, *tmp; 35 36 __asm__ volatile( 37 "ldrb %w[bit] , [%[state]] \n\t" 38 "add %[r_b] , %[tables] , %[lps_off] \n\t" 39 "mov %w[tmp] , %w[range] \n\t" 40 "and %w[range] , %w[range] , #0xC0 \n\t" 41 "lsl %w[r_c] , %w[range] , #1 \n\t" 42 "add %[r_b] , %[r_b] , %w[bit], UXTW \n\t" 43 "ldrb %w[range] , [%[r_b], %w[r_c], SXTW] \n\t" 44 "sub %w[r_c] , %w[tmp] , %w[range] \n\t" 45 "lsl %w[tmp] , %w[r_c] , #17 \n\t" 46 "cmp %w[tmp] , %w[low] \n\t" 47 "csel %w[tmp] , %w[tmp] , wzr , cc \n\t" 48 "csel %w[range] , %w[r_c] , %w[range], gt \n\t" 49 "cinv %w[bit] , %w[bit] , cc \n\t" 50 "sub %w[low] , %w[low] , %w[tmp] \n\t" 51 "add %[r_b] , %[tables] , %[norm_off] \n\t" 52 "add %[r_a] , %[tables] , %[mlps_off] \n\t" 53 "ldrb %w[tmp] , [%[r_b], %w[range], SXTW] \n\t" 54 "ldrb %w[r_a] , [%[r_a], %w[bit], SXTW] \n\t" 55 "lsl %w[low] , %w[low] , %w[tmp] \n\t" 56 "lsl %w[range] , %w[range] , %w[tmp] \n\t" 57 "uxth %w[r_c] , %w[low] \n\t" 58 "strb %w[r_a] , [%[state]] \n\t" 59 "cbnz %w[r_c] , 2f \n\t" 60 "ldr %[r_c] , [%[c], %[byte]] \n\t" 61 "ldr %[r_a] , [%[c], %[end]] \n\t" 62 "ldrh %w[tmp] , [%[r_c]] \n\t" 63 "cmp %[r_c] , %[r_a] \n\t" 64 "b.ge 1f \n\t" 65 "add %[r_a] , %[r_c] , #2 \n\t" 66 "str %[r_a] , [%[c], %[byte]] \n\t" 67 "1: \n\t" 68 "sub %w[r_c] , %w[low] , #1 \n\t" 69 "eor %w[r_c] , %w[r_c] , %w[low] \n\t" 70 "rev %w[tmp] , %w[tmp] \n\t" 71 "lsr %w[r_c] , %w[r_c] , #15 \n\t" 72 "lsr %w[tmp] , %w[tmp] , #15 \n\t" 73 "ldrb %w[r_c] , [%[r_b], %w[r_c], SXTW] \n\t" 74 "mov %w[r_b] , #0xFFFF \n\t" 75 "mov %w[r_a] , #7 \n\t" 76 "sub %w[tmp] , %w[tmp] , %w[r_b] \n\t" 77 "sub %w[r_c] , %w[r_a] , %w[r_c] \n\t" 78 "lsl %w[tmp] , %w[tmp] , %w[r_c] \n\t" 79 "add %w[low] , %w[low] , %w[tmp] \n\t" 80 "2: \n\t" 81 : [bit]"=&r"(bit), 82 [low]"+&r"(c->low), 83 [range]"+&r"(c->range), 84 [r_a]"=&r"(reg_a), 85 [r_b]"=&r"(reg_b), 86 [r_c]"=&r"(reg_c), 87 [tmp]"=&r"(tmp) 88 : [c]"r"(c), 89 [state]"r"(state), 90 [tables]"r"(ff_h264_cabac_tables), 91 [byte]"i"(offsetof(CABACContext, bytestream)), 92 [end]"i"(offsetof(CABACContext, bytestream_end)), 93 [norm_off]"I"(H264_NORM_SHIFT_OFFSET), 94 [lps_off]"I"(H264_LPS_RANGE_OFFSET), 95 [mlps_off]"I"(H264_MLPS_STATE_OFFSET + 128) 96 : "memory", "cc" 97 ); 98 99 return bit & 1; 100} 101 102#endif /* HAVE_INLINE_ASM */ 103 104#endif /* AVCODEC_AARCH64_CABAC_H */ 105