avutil/mips: Add msa optimizations for pixelutils

Adapted from the corresponding me_cmp code. Only the width 16 function
has been adapted, because it seems that the width 8 function actually
reads 16 bytes per line.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>

libavutil/mips/Makefile

@@ -1 +1,3 @@
 OBJS += mips/float_dsp_mips.o mips/cpu.o
+
+MSA-OBJS-$(CONFIG_PIXELUTILS) += mips/pixelutils_msa.o

libavutil/mips/pixelutils.h

@@ -0,0 +1,41 @@
+/*
+ * 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
+ */
+
+#ifndef AVUTIL_MIPS_PIXELUTILS_H
+#define AVUTIL_MIPS_PIXELUTILS_H
+
+#include <stddef.h>
+#include <stdint.h>
+
+#include "cpu.h"
+#include "libavutil/attributes.h"
+#include "libavutil/cpu.h"
+#include "libavutil/pixelutils.h"
+
+int ff_pixelutils_sad16_msa(const uint8_t *src1, ptrdiff_t stride1,
+                            const uint8_t *src2, ptrdiff_t stride2);
+
+static inline av_cold void ff_pixelutils_sad_init_mips(av_pixelutils_sad_fn *sad, int aligned)
+{
+    int cpu_flags = av_get_cpu_flags();
+
+    if (have_msa(cpu_flags)) {
+        sad[3] = ff_pixelutils_sad16_msa;
+    }
+}
+#endif

libavutil/mips/pixelutils_msa.c

@@ -0,0 +1,48 @@
+/*
+ * Copyright (c) 2015 Parag Salasakar (Parag.Salasakar@imgtec.com)
+ *
+ * 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 <stddef.h>
+#include <stdint.h>
+
+#include "generic_macros_msa.h"
+#include "pixelutils.h"
+
+int ff_pixelutils_sad16_msa(const uint8_t *src, ptrdiff_t src_stride,
+                            const uint8_t *ref, ptrdiff_t ref_stride)
+{
+    int32_t ht_cnt = 16/4;
+    v16u8 src0, src1, ref0, ref1;
+    v8u16 sad = { 0 };
+
+    for (; ht_cnt--; ) {
+        LD_UB2(src, src_stride, src0, src1);
+        src += (2 * src_stride);
+        LD_UB2(ref, ref_stride, ref0, ref1);
+        ref += (2 * ref_stride);
+        sad += SAD_UB2_UH(src0, src1, ref0, ref1);
+
+        LD_UB2(src, src_stride, src0, src1);
+        src += (2 * src_stride);
+        LD_UB2(ref, ref_stride, ref0, ref1);
+        ref += (2 * ref_stride);
+        sad += SAD_UB2_UH(src0, src1, ref0, ref1);
+    }
+    return (HADD_UH_U32(sad));
+}

libavutil/pixelutils.c

@@ -32,6 +32,8 @@
 #include "aarch64/pixelutils.h"
 #elif ARCH_ARM && HAVE_ARMV6
 #include "arm/pixelutils.h"
+#elif ARCH_MIPS && HAVE_MSA
+#include "mips/pixelutils.h"
 #elif ARCH_RISCV
 #include "riscv/pixelutils.h"
 #elif ARCH_X86 && HAVE_X86ASM
@@ -98,6 +100,8 @@ av_pixelutils_sad_fn av_pixelutils_get_sad_fn(int w_bits, int h_bits, int aligne
     ff_pixelutils_sad_init_aarch64(sad, aligned);
 #elif ARCH_ARM
     ff_pixelutils_sad_init_arm(sad, aligned);
+#elif ARCH_MIPS && HAVE_MSA
+    ff_pixelutils_sad_init_mips(sad, aligned);
 #elif ARCH_RISCV
     ff_pixelutils_init_riscv(sad, aligned);
 #elif ARCH_X86 && HAVE_X86ASM