Line data    Source code

       1             : // Copyright (c) 2010 The Chromium Authors. All rights reserved.
       2             : // Use of this source code is governed by a BSD-style license that can be
       3             : // found in the LICENSE file.
       4             : 
       5             : #include <mmintrin.h>
       6             : #include "yuv_row.h"
       7             : 
       8             : namespace mozilla {
       9             : namespace gfx {
      10             : 
      11             : // FilterRows combines two rows of the image using linear interpolation.
      12             : // MMX version does 8 pixels at a time.
      13           0 : void FilterRows_MMX(uint8* ybuf, const uint8* y0_ptr, const uint8* y1_ptr,
      14             :                     int source_width, int source_y_fraction) {
      15           0 :   __m64 zero = _mm_setzero_si64();
      16           0 :   __m64 y1_fraction = _mm_set1_pi16(source_y_fraction);
      17           0 :   __m64 y0_fraction = _mm_set1_pi16(256 - source_y_fraction);
      18             : 
      19           0 :   const __m64* y0_ptr64 = reinterpret_cast<const __m64*>(y0_ptr);
      20           0 :   const __m64* y1_ptr64 = reinterpret_cast<const __m64*>(y1_ptr);
      21           0 :   __m64* dest64 = reinterpret_cast<__m64*>(ybuf);
      22           0 :   __m64* end64 = reinterpret_cast<__m64*>(ybuf + source_width);
      23             : 
      24           0 :   do {
      25           0 :     __m64 y0 = *y0_ptr64++;
      26           0 :     __m64 y1 = *y1_ptr64++;
      27           0 :     __m64 y2 = _mm_unpackhi_pi8(y0, zero);
      28           0 :     __m64 y3 = _mm_unpackhi_pi8(y1, zero);
      29           0 :     y0 = _mm_unpacklo_pi8(y0, zero);
      30           0 :     y1 = _mm_unpacklo_pi8(y1, zero);
      31           0 :     y0 = _mm_mullo_pi16(y0, y0_fraction);
      32           0 :     y1 = _mm_mullo_pi16(y1, y1_fraction);
      33           0 :     y2 = _mm_mullo_pi16(y2, y0_fraction);
      34           0 :     y3 = _mm_mullo_pi16(y3, y1_fraction);
      35           0 :     y0 = _mm_add_pi16(y0, y1);
      36           0 :     y2 = _mm_add_pi16(y2, y3);
      37           0 :     y0 = _mm_srli_pi16(y0, 8);
      38           0 :     y2 = _mm_srli_pi16(y2, 8);
      39           0 :     y0 = _mm_packs_pu16(y0, y2);
      40           0 :     *dest64++ = y0;
      41           0 :   } while (dest64 < end64);
      42           0 : }
      43             : 
      44             : } // namespace gfx
      45             : } // namespace mozilla