libavcodec: aarch64: Add a NEON implementation of pixblockdsp

                        Cortex A53    A72    A73
get_pixels_c:                140.7   87.7   72.5
get_pixels_neon:              46.0   20.0   19.5
get_pixels_unaligned_c:      140.7   87.7   73.0
get_pixels_unaligned_neon:    49.2   20.2   26.2
diff_pixels_c:               209.7  133.7  138.7
diff_pixels_neon:             54.2   31.7   23.5
diff_pixels_unaligned_c:     209.7  134.2  139.0
diff_pixels_unaligned_neon:   68.0   27.7   41.7
Signed-off-by: Martin Storsjö <martin@martin.st>

libavcodec/aarch64/Makefile

@@ -9,6 +9,7 @@ OBJS-$(CONFIG_HPELDSP)                  += aarch64/hpeldsp_init_aarch64.o
 OBJS-$(CONFIG_IDCTDSP)                  += aarch64/idctdsp_init_aarch64.o
 OBJS-$(CONFIG_MPEGAUDIODSP)             += aarch64/mpegaudiodsp_init.o
 OBJS-$(CONFIG_NEON_CLOBBER_TEST)        += aarch64/neontest.o
+OBJS-$(CONFIG_PIXBLOCKDSP)              += aarch64/pixblockdsp_init_aarch64.o
 OBJS-$(CONFIG_VIDEODSP)                 += aarch64/videodsp_init.o
 OBJS-$(CONFIG_VP8DSP)                   += aarch64/vp8dsp_init_aarch64.o
 
@@ -46,6 +47,7 @@ NEON-OBJS-$(CONFIG_HPELDSP)             += aarch64/hpeldsp_neon.o
 NEON-OBJS-$(CONFIG_IDCTDSP)             += aarch64/simple_idct_neon.o
 NEON-OBJS-$(CONFIG_MDCT)                += aarch64/mdct_neon.o
 NEON-OBJS-$(CONFIG_MPEGAUDIODSP)        += aarch64/mpegaudiodsp_neon.o
+NEON-OBJS-$(CONFIG_PIXBLOCKDSP)         += aarch64/pixblockdsp_neon.o
 NEON-OBJS-$(CONFIG_VP8DSP)              += aarch64/vp8dsp_neon.o
 
 # decoders/encoders

libavcodec/aarch64/pixblockdsp_init_aarch64.c

+/*
+ * 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 <stdint.h>
+
+#include "libavutil/attributes.h"
+#include "libavutil/cpu.h"
+#include "libavutil/aarch64/cpu.h"
+#include "libavcodec/avcodec.h"
+#include "libavcodec/pixblockdsp.h"
+
+void ff_get_pixels_neon(int16_t *block, const uint8_t *pixels,
+                        ptrdiff_t stride);
+void ff_diff_pixels_neon(int16_t *block, const uint8_t *s1,
+                         const uint8_t *s2, ptrdiff_t stride);
+
+av_cold void ff_pixblockdsp_init_aarch64(PixblockDSPContext *c,
+                                         AVCodecContext *avctx,
+                                         unsigned high_bit_depth)
+{
+    int cpu_flags = av_get_cpu_flags();
+
+    if (have_neon(cpu_flags)) {
+        if (!high_bit_depth) {
+            c->get_pixels_unaligned =
+            c->get_pixels = ff_get_pixels_neon;
+        }
+        c->diff_pixels_unaligned =
+        c->diff_pixels = ff_diff_pixels_neon;
+    }
+}

libavcodec/aarch64/pixblockdsp_neon.S

+/*
+ * Copyright (c) 2020 Martin Storsjo
+ *
+ * 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 "libavutil/aarch64/asm.S"
+
+function ff_get_pixels_neon, export=1
+        mov             w3,  #8
+1:
+        ld1             {v0.8b}, [x1], x2
+        subs            w3,  w3,  #2
+        ld1             {v1.8b}, [x1], x2
+        uxtl            v0.8h,   v0.8b
+        uxtl            v1.8h,   v1.8b
+        st1             {v0.8h, v1.8h}, [x0], #32
+        b.gt            1b
+
+        ret
+endfunc
+
+function ff_diff_pixels_neon, export=1
+        mov             w4,  #8
+1:
+        ld1             {v0.8b}, [x1], x3
+        ld1             {v1.8b}, [x2], x3
+        subs            w4,  w4,  #2
+        ld1             {v2.8b}, [x1], x3
+        usubl           v0.8h,   v0.8b,   v1.8b
+        ld1             {v3.8b}, [x2], x3
+        usubl           v1.8h,   v2.8b,   v3.8b
+        st1             {v0.8h, v1.8h}, [x0], #32
+        b.gt            1b
+
+        ret
+endfunc

libavcodec/pixblockdsp.c

@@ -101,6 +101,8 @@ av_cold void ff_pixblockdsp_init(PixblockDSPContext *c, AVCodecContext *avctx)
         break;
     }
 
+    if (ARCH_AARCH64)
+        ff_pixblockdsp_init_aarch64(c, avctx, high_bit_depth);
     if (ARCH_ALPHA)
         ff_pixblockdsp_init_alpha(c, avctx, high_bit_depth);
     if (ARCH_ARM)

libavcodec/pixblockdsp.h

@@ -44,6 +44,8 @@ typedef struct PixblockDSPContext {
 } PixblockDSPContext;
 
 void ff_pixblockdsp_init(PixblockDSPContext *c, AVCodecContext *avctx);
+void ff_pixblockdsp_init_aarch64(PixblockDSPContext *c, AVCodecContext *avctx,
+                                 unsigned high_bit_depth);
 void ff_pixblockdsp_init_alpha(PixblockDSPContext *c, AVCodecContext *avctx,
                                unsigned high_bit_depth);
 void ff_pixblockdsp_init_arm(PixblockDSPContext *c, AVCodecContext *avctx,