Merge "SSE2 inverse 4x4 2D-DCT with DC only"

vp9/common/vp9_rtcd_defs.sh

@@ -292,7 +292,7 @@ specialize vp9_convolve8_avg_vert ssse3 neon
 # dct
 #
 prototype void vp9_short_idct4x4_1_add "int16_t *input, uint8_t *dest, int dest_stride"
-specialize vp9_short_idct4x4_1_add
+specialize vp9_short_idct4x4_1_add sse2
 
 prototype void vp9_short_idct4x4_add "int16_t *input, uint8_t *dest, int dest_stride"
 specialize vp9_short_idct4x4_add sse2

vp9/common/x86/vp9_idct_intrin_sse2.c

@@ -148,6 +148,23 @@ void vp9_short_idct4x4_add_sse2(int16_t *input, uint8_t *dest, int stride) {
   RECON_AND_STORE4X4(dest, input3);
 }
 
+void vp9_short_idct4x4_1_add_sse2(int16_t *input, uint8_t *dest, int stride) {
+  __m128i dc_value;
+  const __m128i zero = _mm_setzero_si128();
+  int a;
+
+  a = dct_const_round_shift(input[0] * cospi_16_64);
+  a = dct_const_round_shift(a * cospi_16_64);
+  a = ROUND_POWER_OF_TWO(a, 4);
+
+  dc_value = _mm_set1_epi16(a);
+
+  RECON_AND_STORE4X4(dest, dc_value);
+  RECON_AND_STORE4X4(dest, dc_value);
+  RECON_AND_STORE4X4(dest, dc_value);
+  RECON_AND_STORE4X4(dest, dc_value);
+}
+
 void vp9_idct4_1d_sse2(int16_t *input, int16_t *output) {
   const __m128i zero = _mm_setzero_si128();
   const __m128i c1 = _mm_setr_epi16((int16_t)cospi_16_64, (int16_t)cospi_16_64,