libvpx: Pull from upstream

source/libvpx/vp9/encoder/vp9_pickmode.c

 /*
  *  Copyright (c) 2014 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 236 matching lines @@
   for (i = 0; i < len; i++) {
     if (!p[i].in_use) {
       p[i].in_use = 1;
       return i;
     }
   }
   return -1;
 }
 
 static void free_pred_buffer(PRED_BUFFER *p) {
-  p->in_use = 0;
+  if (p != NULL)
+    p->in_use = 0;
 }
 
 static void encode_breakout_test(VP9_COMP *cpi, MACROBLOCK *x,
                                  BLOCK_SIZE bsize, int mi_row, int mi_col,
                                  MV_REFERENCE_FRAME ref_frame,
                                  PREDICTION_MODE this_mode,
                                  unsigned int var_y, unsigned int sse_y,
                                  struct buf_2d yv12_mb[][MAX_MB_PLANE],
                                  int *rate, int64_t *dist) {
   MACROBLOCKD *xd = &x->e_mbd;
@@ skipping 396 matching lines @@
         best_rd = this_rd;
         *returnrate = rate;
         *returndistortion = dist;
         best_mode = this_mode;
         best_pred_filter = mbmi->interp_filter;
         best_tx_size = mbmi->tx_size;
         best_ref_frame = ref_frame;
         skip_txfm = x->skip_txfm[0];
 
         if (cpi->sf.reuse_inter_pred_sby) {
-          if (best_pred != NULL)
-            free_pred_buffer(best_pred);
+          free_pred_buffer(best_pred);
 
           best_pred = this_mode_pred;
         }
       } else {
         if (cpi->sf.reuse_inter_pred_sby)
           free_pred_buffer(this_mode_pred);
       }
 
       if (x->skip)
         break;
     }
     // If the current reference frame is valid and we found a usable mode,
     // we are done.
     if (best_rd < INT64_MAX)
       break;
   }
 
   // If best prediction is not in dst buf, then copy the prediction block from
   // temp buf to dst buf.
-  if (cpi->sf.reuse_inter_pred_sby && best_pred->data != orig_dst.buf) {
+  if (best_pred != NULL && cpi->sf.reuse_inter_pred_sby &&
+      best_pred->data != orig_dst.buf) {
     uint8_t *copy_from, *copy_to;
 
     pd->dst = orig_dst;
     copy_to = pd->dst.buf;
 
     copy_from = best_pred->data;
 
     vp9_convolve_copy(copy_from, bw, copy_to, pd->dst.stride, NULL, 0, NULL, 0,
                       bw, bh);
   }
@@ skipping 48 matching lines @@
       } else {
         x->skip_txfm[0] = skip_txfm;
       }
     }
     if (cpi->sf.reuse_inter_pred_sby)
       pd->dst = orig_dst;
   }
 
   return INT64_MAX;
 }