Revert "libvpx: Pull from upstream"

source/libvpx/vp9/encoder/vp9_mcomp.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 72 matching lines @@
     const MV diff = { mv->row - ref->row,
                       mv->col - ref->col };
     return ROUND_POWER_OF_TWO(mv_cost(&diff, mvjcost, mvcost) *
                                   error_per_bit, 13);
   }
   return 0;
 }
 
 static int mvsad_err_cost(const MACROBLOCK *x, const MV *mv, const MV *ref,
                           int error_per_bit) {
-  const MV diff = { mv->row - ref->row,
-                    mv->col - ref->col };
-  return ROUND_POWER_OF_TWO(mv_cost(&diff, x->nmvjointsadcost,
-                                    x->nmvsadcost) * error_per_bit, 8);
+  if (x->nmvsadcost) {
+    const MV diff = { mv->row - ref->row,
+                      mv->col - ref->col };
+    return ROUND_POWER_OF_TWO(mv_cost(&diff, x->nmvjointsadcost,
+                                      x->nmvsadcost) * error_per_bit, 8);
+  }
+  return 0;
 }
 
 void vp9_init_dsmotion_compensation(search_site_config *cfg, int stride) {
   int len, ss_count = 1;
 
   cfg->ss[0].mv.col = cfg->ss[0].mv.row = 0;
   cfg->ss[0].offset = 0;
 
   for (len = MAX_FIRST_STEP; len > 0; len /= 2) {
     // Generate offsets for 4 search sites per step.
@@ skipping 2033 matching lines @@
       break;
     default:
       assert(0 && "Invalid search method.");
   }
 
   if (method != NSTEP && rd && var < var_max)
     var = vp9_get_mvpred_var(x, tmp_mv, ref_mv, fn_ptr, 1);
 
   return var;
 }