ffmpeg/libavcodec/loongarch/h264_cabac.c

141 lines
6.0 KiB
C

/*
* Loongson optimized cabac
*
* Copyright (c) 2021 Loongson Technology Corporation Limited
* Contributed by Hao Chen <chenhao@loongson.cn>
*
* 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
*/
#include "libavcodec/cabac.h"
#include "cabac.h"
#define decode_significance decode_significance_loongarch
static int decode_significance_loongarch(CABACContext *c, int max_coeff,
uint8_t *significant_coeff_ctx_base, int *index, int64_t last_off)
{
void *end = significant_coeff_ctx_base + max_coeff - 1;
int64_t minusstart = -(int64_t)significant_coeff_ctx_base;
int64_t minusindex = 4 - (int64_t)index;
int64_t bit, tmp0, tmp1, tmp2, one = 1;
uint8_t *state = significant_coeff_ctx_base;
__asm__ volatile(
"3:"
#if UNCHECKED_BITSTREAM_READER
GET_CABAC_LOONGARCH_UNCBSR
#else
GET_CABAC_LOONGARCH
#endif
"blt %[bit], %[one], 4f \n\t"
"add.d %[state], %[state], %[last_off] \n\t"
#if UNCHECKED_BITSTREAM_READER
GET_CABAC_LOONGARCH_UNCBSR
#else
GET_CABAC_LOONGARCH
#endif
"sub.d %[state], %[state], %[last_off] \n\t"
"add.d %[tmp0], %[state], %[minusstart] \n\t"
"st.w %[tmp0], %[index], 0 \n\t"
"bge %[bit], %[one], 5f \n\t"
"addi.d %[index], %[index], 4 \n\t"
"4: \n\t"
"addi.d %[state], %[state], 1 \n\t"
"blt %[state], %[end], 3b \n\t"
"add.d %[tmp0], %[state], %[minusstart] \n\t"
"st.w %[tmp0], %[index], 0 \n\t"
"5: \n\t"
"add.d %[tmp0], %[index], %[minusindex] \n\t"
"srli.d %[tmp0], %[tmp0], 2 \n\t"
: [bit]"=&r"(bit), [tmp0]"=&r"(tmp0), [tmp1]"=&r"(tmp1), [tmp2]"=&r"(tmp2),
[c_range]"+&r"(c->range), [c_low]"+&r"(c->low), [state]"+&r"(state),
[c_bytestream]"+&r"(c->bytestream), [index]"+&r"(index)
: [tables]"r"(ff_h264_cabac_tables), [end]"r"(end), [one]"r"(one),
[minusstart]"r"(minusstart), [minusindex]"r"(minusindex),
[last_off]"r"(last_off),
#if !UNCHECKED_BITSTREAM_READER
[c_bytestream_end]"r"(c->bytestream_end),
#endif
[lps_off]"i"(H264_LPS_RANGE_OFFSET),
[mlps_off]"i"(H264_MLPS_STATE_OFFSET + 128),
[norm_off]"i"(H264_NORM_SHIFT_OFFSET),
[cabac_mask]"r"(CABAC_MASK)
: "memory"
);
return (int)tmp0;
}
#define decode_significance_8x8 decode_significance_8x8_loongarch
static int decode_significance_8x8_loongarch(
CABACContext *c, uint8_t *significant_coeff_ctx_base,
int *index, uint8_t *last_coeff_ctx_base, const uint8_t *sig_off)
{
int64_t minusindex = 4 - (int64_t)index;
int64_t bit, tmp0, tmp1, tmp2, one = 1, end = 63, last = 0;
uint8_t *state = 0;
int64_t flag_offset = H264_LAST_COEFF_FLAG_OFFSET_8x8_OFFSET;
__asm__ volatile(
"3: \n\t"
"ldx.bu %[tmp0], %[sig_off], %[last] \n\t"
"add.d %[state], %[tmp0], %[significant_coeff_ctx_base] \n\t"
#if UNCHECKED_BITSTREAM_READER
GET_CABAC_LOONGARCH_UNCBSR
#else
GET_CABAC_LOONGARCH
#endif
"blt %[bit], %[one], 4f \n\t"
"add.d %[tmp0], %[tables], %[flag_offset] \n\t"
"ldx.bu %[tmp1], %[tmp0], %[last] \n\t"
"add.d %[state], %[tmp1], %[last_coeff_ctx_base] \n\t"
#if UNCHECKED_BITSTREAM_READER
GET_CABAC_LOONGARCH_UNCBSR
#else
GET_CABAC_LOONGARCH
#endif
"st.w %[last], %[index], 0 \n\t"
"bge %[bit], %[one], 5f \n\t"
"addi.d %[index], %[index], 4 \n\t"
"4: \n\t"
"addi.d %[last], %[last], 1 \n\t"
"blt %[last], %[end], 3b \n\t"
"st.w %[last], %[index], 0 \n\t"
"5: \n\t"
"add.d %[tmp0], %[index], %[minusindex] \n\t"
"srli.d %[tmp0], %[tmp0], 2 \n\t"
: [bit]"=&r"(bit), [tmp0]"=&r"(tmp0), [tmp1]"=&r"(tmp1),
[tmp2]"=&r"(tmp2), [c_range]"+&r"(c->range),
[c_low]"+&r"(c->low), [state]"+&r"(state), [last]"+&r"(last),
[c_bytestream]"+&r"(c->bytestream), [index]"+&r"(index)
: [tables]"r"(ff_h264_cabac_tables), [end]"r"(end),
[one]"r"(one), [minusindex]"r"(minusindex),
[last_coeff_ctx_base]"r"(last_coeff_ctx_base),
[flag_offset]"r"(flag_offset),
#if !UNCHECKED_BITSTREAM_READER
[c_bytestream_end]"r"(c->bytestream_end),
#endif
[lps_off]"i"(H264_LPS_RANGE_OFFSET), [sig_off]"r"(sig_off),
[mlps_off]"i"(H264_MLPS_STATE_OFFSET + 128),
[norm_off]"i"(H264_NORM_SHIFT_OFFSET),
[cabac_mask]"r"(CABAC_MASK),
[significant_coeff_ctx_base]"r"(significant_coeff_ctx_base)
);
return (int)tmp0;
}