shithub: libvpx

Download patch

ref: 188d58eaa99ed5b47af77b354e303a82614ce62a
parent: 9b0d306a2fcbdefe31fa35a367293dbf23af0048
author: Johann <johannkoenig@google.com>
date: Thu May 4 04:39:12 EDT 2017

sub pel variance neon: 4x block sizes

Add optimizations for blocks of width 4

BUG=webm:1423

Change-Id: Idfb458d36db3014d48fbfbe7f5462aa6eb249938

--- a/test/variance_test.cc
+++ b/test/variance_test.cc
@@ -1275,7 +1275,9 @@
                       make_tuple(4, 3, &vpx_sub_pixel_variance16x8_neon, 0),
                       make_tuple(3, 4, &vpx_sub_pixel_variance8x16_neon, 0),
                       make_tuple(3, 3, &vpx_sub_pixel_variance8x8_neon, 0),
-                      make_tuple(3, 2, &vpx_sub_pixel_variance8x4_neon, 0)));
+                      make_tuple(3, 2, &vpx_sub_pixel_variance8x4_neon, 0),
+                      make_tuple(2, 3, &vpx_sub_pixel_variance4x8_neon, 0),
+                      make_tuple(2, 2, &vpx_sub_pixel_variance4x4_neon, 0)));
 
 INSTANTIATE_TEST_CASE_P(
     NEON, VpxSubpelAvgVarianceTest,
--- a/vpx_dsp/arm/mem_neon.h
+++ b/vpx_dsp/arm/mem_neon.h
@@ -79,6 +79,32 @@
   memcpy(buf, &a, 4);
 }
 
+// Load 2 sets of 4 bytes when alignment is not guaranteed.
+static INLINE uint8x8_t load_unaligned_u8(const uint8_t *buf, int stride) {
+  uint32_t a;
+  uint32x2_t a_u32 = vdup_n_u32(0);
+  if (stride == 4) return vld1_u8(buf);
+  memcpy(&a, buf, 4);
+  buf += stride;
+  a_u32 = vld1_lane_u32(&a, a_u32, 0);
+  memcpy(&a, buf, 4);
+  a_u32 = vld1_lane_u32(&a, a_u32, 1);
+  return vreinterpret_u8_u32(a_u32);
+}
+
+// Store 2 sets of 4 bytes when alignment is not guaranteed.
+static INLINE void store_unaligned_u8(uint8_t *buf, int stride,
+                                      const uint8x8_t a) {
+  const uint32x2_t a_u32 = vreinterpret_u32_u8(a);
+  if (stride == 4) {
+    vst1_u8(buf, a);
+    return;
+  }
+  uint32_to_mem(buf, vget_lane_u32(a_u32, 0));
+  buf += stride;
+  uint32_to_mem(buf, vget_lane_u32(a_u32, 1));
+}
+
 // Load 4 sets of 4 bytes when alignment is not guaranteed.
 static INLINE uint8x16_t load_unaligned_u8q(const uint8_t *buf, int stride) {
   uint32_t a;
--- a/vpx_dsp/arm/subpel_variance_neon.c
+++ b/vpx_dsp/arm/subpel_variance_neon.c
@@ -16,6 +16,7 @@
 #include "vpx/vpx_integer.h"
 
 #include "vpx_dsp/variance.h"
+#include "vpx_dsp/arm/mem_neon.h"
 
 static const uint8_t bilinear_filters[8][2] = {
   { 128, 0 }, { 112, 16 }, { 96, 32 }, { 80, 48 },
@@ -22,6 +23,30 @@
   { 64, 64 }, { 48, 80 },  { 32, 96 }, { 16, 112 },
 };
 
+// Process a block exactly 4 wide and a multiple of 2 high.
+static void var_filter_block2d_bil_w4(const uint8_t *src_ptr,
+                                      uint8_t *output_ptr,
+                                      unsigned int src_pixels_per_line,
+                                      int pixel_step,
+                                      unsigned int output_height,
+                                      const uint8_t *filter) {
+  const uint8x8_t f0 = vmov_n_u8(filter[0]);
+  const uint8x8_t f1 = vmov_n_u8(filter[1]);
+  unsigned int i;
+  for (i = 0; i < output_height; i += 2) {
+    const uint8x8_t src_0 = load_unaligned_u8(src_ptr, src_pixels_per_line);
+    const uint8x8_t src_1 =
+        load_unaligned_u8(src_ptr + pixel_step, src_pixels_per_line);
+    const uint16x8_t a = vmull_u8(src_0, f0);
+    const uint16x8_t b = vmlal_u8(a, src_1, f1);
+    const uint8x8_t out = vrshrn_n_u16(b, FILTER_BITS);
+    store_unaligned_u8(output_ptr, 4, out);
+    // Next row...
+    src_ptr += 2 * src_pixels_per_line;
+    output_ptr += 8;
+  }
+}
+
 // Process a block exactly 8 wide and any height.
 static void var_filter_block2d_bil_w8(const uint8_t *src_ptr,
                                       uint8_t *output_ptr,
@@ -74,28 +99,36 @@
   }
 }
 
-// TODO(johannkoenig): support 4xM block sizes.
-#define sub_pixel_varianceNxM(n, m)                                  \
-  uint32_t vpx_sub_pixel_variance##n##x##m##_neon(                   \
-      const uint8_t *a, int a_stride, int xoffset, int yoffset,      \
-      const uint8_t *b, int b_stride, uint32_t *sse) {               \
-    DECLARE_ALIGNED(16, uint8_t, fdata3[n * (m + 1)]);               \
-    DECLARE_ALIGNED(16, uint8_t, temp2[n * m]);                      \
-                                                                     \
-    if (n == 8) {                                                    \
-      var_filter_block2d_bil_w8(a, fdata3, a_stride, 1, (m + 1),     \
-                                bilinear_filters[xoffset]);          \
-      var_filter_block2d_bil_w8(fdata3, temp2, n, n, m,              \
-                                bilinear_filters[yoffset]);          \
-    } else {                                                         \
-      var_filter_block2d_bil_w16(a, fdata3, a_stride, 1, (m + 1), n, \
-                                 bilinear_filters[xoffset]);         \
-      var_filter_block2d_bil_w16(fdata3, temp2, n, n, m, n,          \
-                                 bilinear_filters[yoffset]);         \
-    }                                                                \
-    return vpx_variance##n##x##m(temp2, n, b, b_stride, sse);        \
+// 4xM filter writes an extra row to fdata because it processes two rows at a
+// time.
+#define sub_pixel_varianceNxM(n, m)                                   \
+  uint32_t vpx_sub_pixel_variance##n##x##m##_neon(                    \
+      const uint8_t *a, int a_stride, int xoffset, int yoffset,       \
+      const uint8_t *b, int b_stride, uint32_t *sse) {                \
+    DECLARE_ALIGNED(16, uint8_t, fdata3[n * (m + (n == 4 ? 2 : 1))]); \
+    DECLARE_ALIGNED(16, uint8_t, temp2[n * m]);                       \
+                                                                      \
+    if (n == 4) {                                                     \
+      var_filter_block2d_bil_w4(a, fdata3, a_stride, 1, (m + 2),      \
+                                bilinear_filters[xoffset]);           \
+      var_filter_block2d_bil_w4(fdata3, temp2, n, n, m,               \
+                                bilinear_filters[yoffset]);           \
+    } else if (n == 8) {                                              \
+      var_filter_block2d_bil_w8(a, fdata3, a_stride, 1, (m + 1),      \
+                                bilinear_filters[xoffset]);           \
+      var_filter_block2d_bil_w8(fdata3, temp2, n, n, m,               \
+                                bilinear_filters[yoffset]);           \
+    } else {                                                          \
+      var_filter_block2d_bil_w16(a, fdata3, a_stride, 1, (m + 1), n,  \
+                                 bilinear_filters[xoffset]);          \
+      var_filter_block2d_bil_w16(fdata3, temp2, n, n, m, n,           \
+                                 bilinear_filters[yoffset]);          \
+    }                                                                 \
+    return vpx_variance##n##x##m(temp2, n, b, b_stride, sse);         \
   }
 
+sub_pixel_varianceNxM(4, 4);
+sub_pixel_varianceNxM(4, 8);
 sub_pixel_varianceNxM(8, 4);
 sub_pixel_varianceNxM(8, 8);
 sub_pixel_varianceNxM(8, 16);
--- a/vpx_dsp/vpx_dsp_rtcd_defs.pl
+++ b/vpx_dsp/vpx_dsp_rtcd_defs.pl
@@ -1214,10 +1214,10 @@
   specialize qw/vpx_sub_pixel_variance8x4 neon msa sse2 ssse3/;
 
 add_proto qw/uint32_t vpx_sub_pixel_variance4x8/, "const uint8_t *src_ptr, int source_stride, int xoffset, int  yoffset, const uint8_t *ref_ptr, int ref_stride, uint32_t *sse";
-  specialize qw/vpx_sub_pixel_variance4x8 msa sse2 ssse3/;
+  specialize qw/vpx_sub_pixel_variance4x8 neon msa sse2 ssse3/;
 
 add_proto qw/uint32_t vpx_sub_pixel_variance4x4/, "const uint8_t *src_ptr, int source_stride, int xoffset, int  yoffset, const uint8_t *ref_ptr, int ref_stride, uint32_t *sse";
-  specialize qw/vpx_sub_pixel_variance4x4 msa sse2 ssse3/;
+  specialize qw/vpx_sub_pixel_variance4x4 neon msa sse2 ssse3/;
 
 add_proto qw/uint32_t vpx_sub_pixel_avg_variance64x64/, "const uint8_t *src_ptr, int source_stride, int xoffset, int  yoffset, const uint8_t *ref_ptr, int ref_stride, uint32_t *sse, const uint8_t *second_pred";
   specialize qw/vpx_sub_pixel_avg_variance64x64 neon avx2 msa sse2 ssse3/;