libvpx: Pull from upstream

source/libvpx/vp9/common/vp9_reconinter.c

 /*
  *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE 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.
  */
 
@@ skipping 169 matching lines @@
     const MV mv_q4 = clamp_mv_to_umv_border_sb(xd, &mv, bw, bh,
                                                pd->subsampling_x,
                                                pd->subsampling_y);
 
     uint8_t *pre;
     MV32 scaled_mv;
     int xs, ys, subpel_x, subpel_y;
     const int is_scaled = vp9_is_scaled(sf);
 
     if (is_scaled) {
-      pre = pre_buf->buf + scaled_buffer_offset(x, y, pre_buf->stride, sf);
+      // Co-ordinate of containing block to pixel precision.
+      const int x_start = (-xd->mb_to_left_edge >> (3 + pd->subsampling_x));
+      const int y_start = (-xd->mb_to_top_edge >> (3 + pd->subsampling_y));
+      if (plane == 0)
+        pre_buf->buf = xd->block_refs[ref]->buf->y_buffer;
+      else if (plane == 1)
+        pre_buf->buf = xd->block_refs[ref]->buf->u_buffer;
+      else
+        pre_buf->buf = xd->block_refs[ref]->buf->v_buffer;
+
+      pre_buf->buf += scaled_buffer_offset(x_start + x, y_start + y,
+                                           pre_buf->stride, sf);
+      pre = pre_buf->buf;
       scaled_mv = vp9_scale_mv(&mv_q4, mi_x + x, mi_y + y, sf);
       xs = sf->x_step_q4;
       ys = sf->y_step_q4;
     } else {
       pre = pre_buf->buf + (y * pre_buf->stride + x);
       scaled_mv.row = mv_q4.row;
       scaled_mv.col = mv_q4.col;
       xs = ys = 16;
     }
     subpel_x = scaled_mv.col & SUBPEL_MASK;
@@ skipping 93 matching lines @@
         src->v_buffer};
     const int strides[MAX_MB_PLANE] = { src->y_stride, src->uv_stride,
         src->uv_stride};
     for (i = 0; i < MAX_MB_PLANE; ++i) {
       struct macroblockd_plane *const pd = &xd->plane[i];
       setup_pred_plane(&pd->pre[idx], buffers[i], strides[i], mi_row, mi_col,
                        sf, pd->subsampling_x, pd->subsampling_y);
     }
   }
 }