Add MSA optimized color transform functions

We add the following MSA optimized color transform functions:
- TransformColor
- SubtractGreenFromBlueAndRed

Change-Id: Ib182d2b5faa7191f503ce70f0dfde0ac89402fd3

Android.mk

@@ -92,6 +92,7 @@ dsp_enc_srcs := \
     src/dsp/lossless_enc.c \
     src/dsp/lossless_enc_mips32.c \
     src/dsp/lossless_enc_mips_dsp_r2.c \
+    src/dsp/lossless_enc_msa.c \
     src/dsp/lossless_enc_neon.$(NEON) \
     src/dsp/lossless_enc_sse2.c \
     src/dsp/lossless_enc_sse41.c \

Makefile.vc

@@ -240,6 +240,7 @@ DSP_ENC_OBJS = \
     $(DIROBJ)\dsp\lossless_enc.obj \
     $(DIROBJ)\dsp\lossless_enc_mips32.obj \
     $(DIROBJ)\dsp\lossless_enc_mips_dsp_r2.obj \
+    $(DIROBJ)\dsp\lossless_enc_msa.obj \
     $(DIROBJ)\dsp\lossless_enc_neon.obj \
     $(DIROBJ)\dsp\lossless_enc_sse2.obj \
     $(DIROBJ)\dsp\lossless_enc_sse41.obj \

build.gradle

@@ -172,6 +172,7 @@ model {
             include "lossless_enc.c"
             include "lossless_enc_mips32.c"
             include "lossless_enc_mips_dsp_r2.c"
+            include "lossless_enc_msa.c"
             include "lossless_enc_neon.$NEON"
             include "lossless_enc_sse2.c"
             include "lossless_enc_sse41.c"

makefile.unix

@@ -184,6 +184,7 @@ DSP_ENC_OBJS = \
     src/dsp/lossless_enc.o \
     src/dsp/lossless_enc_mips32.o \
     src/dsp/lossless_enc_mips_dsp_r2.o \
+    src/dsp/lossless_enc_msa.o \
     src/dsp/lossless_enc_neon.o \
     src/dsp/lossless_enc_sse2.o \
     src/dsp/lossless_enc_sse41.o \

src/dsp/Makefile.am

@@ -114,6 +114,7 @@ libwebpdsp_neon_la_LIBADD = libwebpdspdecode_neon.la
 
 libwebpdsp_msa_la_SOURCES =
 libwebpdsp_msa_la_SOURCES += enc_msa.c
+libwebpdsp_msa_la_SOURCES += lossless_enc_msa.c
 libwebpdsp_msa_la_CPPFLAGS = $(libwebpdsp_la_CPPFLAGS)
 libwebpdsp_msa_la_CFLAGS = $(AM_CFLAGS)
 libwebpdsp_msa_la_LIBADD = libwebpdspdecode_msa.la

src/dsp/lossless_enc.c

@@ -1376,6 +1376,7 @@ extern void VP8LEncDspInitSSE41(void);
 extern void VP8LEncDspInitNEON(void);
 extern void VP8LEncDspInitMIPS32(void);
 extern void VP8LEncDspInitMIPSdspR2(void);
+extern void VP8LEncDspInitMSA(void);
 
 static volatile VP8CPUInfo lossless_enc_last_cpuinfo_used =
     (VP8CPUInfo)&lossless_enc_last_cpuinfo_used;
@@ -1431,6 +1432,11 @@ WEBP_TSAN_IGNORE_FUNCTION void VP8LEncDspInit(void) {
     if (VP8GetCPUInfo(kMIPSdspR2)) {
       VP8LEncDspInitMIPSdspR2();
     }
+#endif
+#if defined(WEBP_USE_MSA)
+    if (VP8GetCPUInfo(kMSA)) {
+      VP8LEncDspInitMSA();
+    }
 #endif
   }
   lossless_enc_last_cpuinfo_used = VP8GetCPUInfo;

src/dsp/lossless_enc_msa.c

@@ -0,0 +1,147 @@
+// Copyright 2016 Google Inc. All Rights Reserved.
+//
+// Use of this source code is governed by a BSD-style license
+// that can be found in the COPYING file in the root of the source
+// tree. An additional intellectual property rights grant can be found
+// in the file PATENTS. All contributing project authors may
+// be found in the AUTHORS file in the root of the source tree.
+// -----------------------------------------------------------------------------
+//
+// MSA variant of Image transform methods for lossless encoder.
+//
+// Authors: Prashant Patil (Prashant.Patil@imgtec.com)
+
+#include "./dsp.h"
+
+#if defined(WEBP_USE_MSA)
+
+#include "./lossless.h"
+#include "./msa_macro.h"
+
+#define TRANSFORM_COLOR_8(src0, src1, dst0, dst1, c0, c1, mask0, mask1) do {  \
+  v8i16 g0, g1, t0, t1, t2, t3;                                               \
+  v4i32 t4, t5;                                                               \
+  VSHF_B2_SH(src0, src0, src1, src1, mask0, mask0, g0, g1);                   \
+  DOTP_SB2_SH(g0, g1, c0, c0, t0, t1);                                        \
+  SRAI_H2_SH(t0, t1, 5);                                                      \
+  t0 = __msa_subv_h((v8i16)src0, t0);                                         \
+  t1 = __msa_subv_h((v8i16)src1, t1);                                         \
+  t4 = __msa_srli_w((v4i32)src0, 16);                                         \
+  t5 = __msa_srli_w((v4i32)src1, 16);                                         \
+  DOTP_SB2_SH(t4, t5, c1, c1, t2, t3);                                        \
+  SRAI_H2_SH(t2, t3, 5);                                                      \
+  SUB2(t0, t2, t1, t3, t0, t1);                                               \
+  VSHF_B2_UB(src0, t0, src1, t1, mask1, mask1, dst0, dst1);                   \
+} while (0)
+
+#define TRANSFORM_COLOR_4(src, dst, c0, c1, mask0, mask1) do {  \
+  const v16i8 g0 = VSHF_SB(src, src, mask0);                    \
+  v8i16 t0 = __msa_dotp_s_h(c0, g0);                            \
+  v8i16 t1;                                                     \
+  v4i32 t2;                                                     \
+  t0 = SRAI_H(t0, 5);                                           \
+  t0 = __msa_subv_h((v8i16)src, t0);                            \
+  t2 = __msa_srli_w((v4i32)src, 16);                            \
+  t1 = __msa_dotp_s_h(c1, (v16i8)t2);                           \
+  t1 = SRAI_H(t1, 5);                                           \
+  t0 = t0 - t1;                                                 \
+  dst = VSHF_UB(src, t0, mask1);                                \
+} while (0)
+
+static void TransformColor(const VP8LMultipliers* const m, uint32_t* data,
+                           int num_pixels) {
+  v16u8 src0, dst0;
+  const v16i8 g2br = (v16i8)__msa_fill_w(m->green_to_blue_ |
+                                         (m->green_to_red_ << 16));
+  const v16i8 r2b = (v16i8)__msa_fill_w(m->red_to_blue_);
+  const v16u8 mask0 = { 1, 255, 1, 255, 5, 255, 5, 255, 9, 255, 9, 255,
+                        13, 255, 13, 255 };
+  const v16u8 mask1 = { 16, 1, 18, 3, 20, 5, 22, 7, 24, 9, 26, 11,
+                        28, 13, 30, 15 };
+
+  while (num_pixels >= 8) {
+    v16u8 src1, dst1;
+    LD_UB2(data, 4, src0, src1);
+    TRANSFORM_COLOR_8(src0, src1, dst0, dst1, g2br, r2b, mask0, mask1);
+    ST_UB2(dst0, dst1, data, 4);
+    data += 8;
+    num_pixels -= 8;
+  }
+  if (num_pixels > 0) {
+    if (num_pixels >= 4) {
+      src0 = LD_UB(data);
+      TRANSFORM_COLOR_4(src0, dst0, g2br, r2b, mask0, mask1);
+      ST_UB(dst0, data);
+      data += 4;
+      num_pixels -= 4;
+    }
+    if (num_pixels > 0) {
+      src0 = LD_UB(data);
+      TRANSFORM_COLOR_4(src0, dst0, g2br, r2b, mask0, mask1);
+      if (num_pixels == 3) {
+        const uint64_t pix_d = __msa_copy_s_d((v2i64)dst0, 0);
+        const uint32_t pix_w = __msa_copy_s_w((v4i32)dst0, 2);
+        SD(pix_d, data + 0);
+        SW(pix_w, data + 2);
+      } else if (num_pixels == 2) {
+        const uint64_t pix_d = __msa_copy_s_d((v2i64)dst0, 0);
+        SD(pix_d, data);
+      } else {
+        const uint32_t pix_w = __msa_copy_s_w((v4i32)dst0, 0);
+        SW(pix_w, data);
+      }
+    }
+  }
+}
+
+static void SubtractGreenFromBlueAndRed(uint32_t* argb_data, int num_pixels) {
+  int i;
+  uint8_t* ptemp_data = (uint8_t*)argb_data;
+  v16u8 src0, dst0, tmp0;
+  const v16u8 mask = { 1, 255, 1, 255, 5, 255, 5, 255, 9, 255, 9, 255,
+                       13, 255, 13, 255 };
+
+  while (num_pixels >= 8) {
+    v16u8 src1, dst1, tmp1;
+    LD_UB2(ptemp_data, 16, src0, src1);
+    VSHF_B2_UB(src0, src1, src1, src0, mask, mask, tmp0, tmp1);
+    SUB2(src0, tmp0, src1, tmp1, dst0, dst1);
+    ST_UB2(dst0, dst1, ptemp_data, 16);
+    ptemp_data += 8 * 4;
+    num_pixels -= 8;
+  }
+  if (num_pixels > 0) {
+    if (num_pixels >= 4) {
+      src0 = LD_UB(ptemp_data);
+      tmp0 = VSHF_UB(src0, src0, mask);
+      dst0 = src0 - tmp0;
+      ST_UB(dst0, ptemp_data);
+      ptemp_data += 4 * 4;
+      num_pixels -= 4;
+    }
+    for (i = 0; i < num_pixels; i++) {
+      const uint8_t b = ptemp_data[0];
+      const uint8_t g = ptemp_data[1];
+      const uint8_t r = ptemp_data[2];
+      ptemp_data[0] = (b - g) & 0xff;
+      ptemp_data[2] = (r - g) & 0xff;
+      ptemp_data += 4;
+    }
+  }
+}
+
+//------------------------------------------------------------------------------
+// Entry point
+
+extern void VP8LEncDspInitMSA(void);
+
+WEBP_TSAN_IGNORE_FUNCTION void VP8LEncDspInitMSA(void) {
+  VP8LSubtractGreenFromBlueAndRed = SubtractGreenFromBlueAndRed;
+  VP8LTransformColor = TransformColor;
+}
+
+#else  // !WEBP_USE_MSA
+
+WEBP_DSP_INIT_STUB(VP8LEncDspInitMSA)
+
+#endif  // WEBP_USE_MSA