libvpx: Pull from upstream

source/libvpx/vp9/decoder/vp9_decoder.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 105 matching lines @@
                                        VP9_REFFRAME ref_frame_flag,
                                        YV12_BUFFER_CONFIG *sd) {
   VP9_COMMON *cm = &pbi->common;
 
   /* TODO(jkoleszar): The decoder doesn't have any real knowledge of what the
    * encoder is using the frame buffers for. This is just a stub to keep the
    * vpxenc --test-decode functionality working, and will be replaced in a
    * later commit that adds VP9-specific controls for this functionality.
    */
   if (ref_frame_flag == VP9_LAST_FLAG) {
-    const YV12_BUFFER_CONFIG *const cfg =
-        &cm->frame_bufs[cm->ref_frame_map[0]].buf;
+    const YV12_BUFFER_CONFIG *const cfg = get_ref_frame(cm, 0);
+    if (cfg == NULL) {
+      vpx_internal_error(&cm->error, VPX_CODEC_ERROR,
+                         "No 'last' reference frame");
+      return VPX_CODEC_ERROR;
+    }
     if (!equal_dimensions(cfg, sd))
       vpx_internal_error(&cm->error, VPX_CODEC_ERROR,
                          "Incorrect buffer dimensions");
     else
       vp8_yv12_copy_frame(cfg, sd);
   } else {
     vpx_internal_error(&cm->error, VPX_CODEC_ERROR,
                        "Invalid reference frame");
   }
 
@@ skipping 36 matching lines @@
 
     // Manage the reference counters and copy image.
     ref_cnt_fb(cm->frame_bufs, ref_fb_ptr, free_fb);
     ref_buf->buf = &cm->frame_bufs[*ref_fb_ptr].buf;
     vp8_yv12_copy_frame(sd, ref_buf->buf);
   }
 
   return cm->error.error_code;
 }
 
-
-int vp9_get_reference_dec(VP9Decoder *pbi, int index, YV12_BUFFER_CONFIG **fb) {
-  VP9_COMMON *cm = &pbi->common;
-
-  if (index < 0 || index >= REF_FRAMES)
-    return -1;
-
-  *fb = &cm->frame_bufs[cm->ref_frame_map[index]].buf;
-  return 0;
-}
-
 /* If any buffer updating is signaled it should be done here. */
 static void swap_frame_buffers(VP9Decoder *pbi) {
   int ref_index = 0, mask;
   VP9_COMMON *const cm = &pbi->common;
 
   for (mask = pbi->refresh_frame_flags; mask; mask >>= 1) {
     if (mask & 1) {
       const int old_idx = cm->ref_frame_map[ref_index];
       ref_cnt_fb(cm->frame_bufs, &cm->ref_frame_map[ref_index],
                  cm->new_fb_idx);
@@ skipping 109 matching lines @@
     *sd = *cm->frame_to_show;
     ret = 0;
   }
 #else
   *sd = *cm->frame_to_show;
   ret = 0;
 #endif /*!CONFIG_POSTPROC*/
   vp9_clear_system_state();
   return ret;
 }