vp9_reconintra_neon: add d135 4x4

based on webp's RD4()

~50% faster over 20M pixels

Change-Id: Ifcb7bf7f7fc8eabf79d9e3b219ce1be67abc524a

test/test_intra_pred_speed.cc

@@ -211,8 +211,8 @@ INTRA_PRED_TEST(DSPR2, TestIntraPred4, vp9_dc_predictor_4x4_dspr2, NULL, NULL,
 INTRA_PRED_TEST(NEON, TestIntraPred4, vp9_dc_predictor_4x4_neon,
                 vp9_dc_left_predictor_4x4_neon, vp9_dc_top_predictor_4x4_neon,
                 vp9_dc_128_predictor_4x4_neon, vp9_v_predictor_4x4_neon,
-                vp9_h_predictor_4x4_neon, NULL, NULL, NULL, NULL, NULL, NULL,
-                vp9_tm_predictor_4x4_neon)
+                vp9_h_predictor_4x4_neon, NULL, vp9_d135_predictor_4x4_neon,
+                NULL, NULL, NULL, NULL, vp9_tm_predictor_4x4_neon)
 #endif  // HAVE_NEON
 
 #if HAVE_MSA

vp9/common/arm/neon/vp9_reconintra_neon.c

@@ -313,6 +313,36 @@ void vp9_dc_128_predictor_32x32_neon(uint8_t *dst, ptrdiff_t stride,
   dc_32x32(dst, stride, NULL, NULL, 0, 0);
 }
 
+// -----------------------------------------------------------------------------
+
+void vp9_d135_predictor_4x4_neon(uint8_t *dst, ptrdiff_t stride,
+                                 const uint8_t *above, const uint8_t *left) {
+  const uint8x8_t XABCD_u8 = vld1_u8(above - 1);
+  const uint64x1_t XABCD = vreinterpret_u64_u8(XABCD_u8);
+  const uint64x1_t ____XABC = vshl_n_u64(XABCD, 32);
+  const uint32x2_t zero = vdup_n_u32(0);
+  const uint32x2_t IJKL = vld1_lane_u32((const uint32_t *)left, zero, 0);
+  const uint8x8_t IJKL_u8 = vreinterpret_u8_u32(IJKL);
+  const uint64x1_t LKJI____ = vreinterpret_u64_u8(vrev32_u8(IJKL_u8));
+  const uint64x1_t LKJIXABC = vorr_u64(LKJI____, ____XABC);
+  const uint8x8_t KJIXABC_ = vreinterpret_u8_u64(vshr_n_u64(LKJIXABC, 8));
+  const uint8x8_t JIXABC__ = vreinterpret_u8_u64(vshr_n_u64(LKJIXABC, 16));
+  const uint8_t D = vget_lane_u8(XABCD_u8, 4);
+  const uint8x8_t JIXABCD_ = vset_lane_u8(D, JIXABC__, 6);
+  const uint8x8_t LKJIXABC_u8 = vreinterpret_u8_u64(LKJIXABC);
+  const uint8x8_t avg1 = vhadd_u8(JIXABCD_, LKJIXABC_u8);
+  const uint8x8_t avg2 = vrhadd_u8(avg1, KJIXABC_);
+  const uint64x1_t avg2_u64 = vreinterpret_u64_u8(avg2);
+  const uint32x2_t r3 = vreinterpret_u32_u8(avg2);
+  const uint32x2_t r2 = vreinterpret_u32_u64(vshr_n_u64(avg2_u64, 8));
+  const uint32x2_t r1 = vreinterpret_u32_u64(vshr_n_u64(avg2_u64, 16));
+  const uint32x2_t r0 = vreinterpret_u32_u64(vshr_n_u64(avg2_u64, 24));
+  vst1_lane_u32((uint32_t *)(dst + 0 * stride), r0, 0);
+  vst1_lane_u32((uint32_t *)(dst + 1 * stride), r1, 0);
+  vst1_lane_u32((uint32_t *)(dst + 2 * stride), r2, 0);
+  vst1_lane_u32((uint32_t *)(dst + 3 * stride), r3, 0);
+}
+
 #if !HAVE_NEON_ASM
 
 void vp9_v_predictor_4x4_neon(uint8_t *dst, ptrdiff_t stride,

vp9/common/vp9_rtcd_defs.pl

@@ -72,7 +72,7 @@ add_proto qw/void vp9_d117_predictor_4x4/, "uint8_t *dst, ptrdiff_t y_stride, co
 specialize qw/vp9_d117_predictor_4x4/;
 
 add_proto qw/void vp9_d135_predictor_4x4/, "uint8_t *dst, ptrdiff_t y_stride, const uint8_t *above, const uint8_t *left";
-specialize qw/vp9_d135_predictor_4x4/;
+specialize qw/vp9_d135_predictor_4x4 neon/;
 
 add_proto qw/void vp9_d153_predictor_4x4/, "uint8_t *dst, ptrdiff_t y_stride, const uint8_t *above, const uint8_t *left";
 specialize qw/vp9_d153_predictor_4x4/, "$ssse3_x86inc";