[FFmpeg-devel] [PATCH 3/3] avcodec: [loongarch] Optimize decode_significance/_8x8_loongarch.
Shiyou Yin
yinshiyou at loongson.cn
Tue Nov 9 09:09:10 EET 2021
From: Hao Chen <chenhao at loongson.cn>
Decoding 1080P H264 from 168fps to 170fps.
Signed-off-by: Shiyou Yin <yinshiyou at loongson.cn>
---
libavcodec/h264_cabac.c | 2 +
libavcodec/loongarch/h264_cabac.c | 140 ++++++++++++++++++++++++++++++
2 files changed, 142 insertions(+)
create mode 100644 libavcodec/loongarch/h264_cabac.c
diff --git a/libavcodec/h264_cabac.c b/libavcodec/h264_cabac.c
index 973b3419c4..040fa0a257 100644
--- a/libavcodec/h264_cabac.c
+++ b/libavcodec/h264_cabac.c
@@ -42,6 +42,8 @@
#if ARCH_X86
#include "x86/h264_cabac.c"
+#elif ARCH_LOONGARCH64
+#include "loongarch/h264_cabac.c"
#endif
/* Cabac pre state table */
diff --git a/libavcodec/loongarch/h264_cabac.c b/libavcodec/loongarch/h264_cabac.c
new file mode 100644
index 0000000000..d88743bed7
--- /dev/null
+++ b/libavcodec/loongarch/h264_cabac.c
@@ -0,0 +1,140 @@
+/*
+ * Loongson optimized cabac
+ *
+ * Copyright (c) 2021 Loongson Technology Corporation Limited
+ * Contributed by Hao Chen <chenhao at 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;
+}
--
2.20.1
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