Fix dependency of loading the heap-number for a double-field store to be the mapcheck.

src/hydrogen-escape-analysis.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
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@@ skipping 194 matching lines @@
           HCheckHeapObject* check = HCheckHeapObject::cast(instr);
           if (check->value() != allocate) continue;
           check->DeleteAndReplaceWith(NULL);
           break;
         }
         case HValue::kCheckMaps: {
           HCheckMaps* mapcheck = HCheckMaps::cast(instr);
           if (mapcheck->value() != allocate) continue;
           // TODO(mstarzinger): This approach breaks if the tracked map value
           // is not a HConstant. Find a repro test case and fix this.
-          for (HUseIterator it(mapcheck->uses()); !it.Done(); it.Advance()) {
-            if (!it.value()->IsLoadNamedField()) continue;
-            HLoadNamedField* load = HLoadNamedField::cast(it.value());
-            load->ClearTypeCheck();
-          }
-          ASSERT(mapcheck->HasNoUses());
-
-          mapcheck->DeleteAndReplaceWith(NULL);
+          ASSERT(mapcheck->ActualValue() == allocate);

[Jakob Kummerow, 2013/08/23 15:41:03]

Looking at the line before (212), I don't think we need this ASSERT.

+          mapcheck->DeleteAndReplaceWith(mapcheck->ActualValue());
           break;
         }
         default:
           // Nothing to see here, move along ...
           break;
       }
     }
 
     // Propagate the block state forward to all successor blocks.
     for (int i = 0; i < block->end()->SuccessorCount(); i++) {
@@ skipping 53 matching lines @@
     AnalyzeDataFlow(allocate);
 
     cumulative_values_ += number_of_values_;
     ASSERT(allocate->HasNoUses());
     ASSERT(!allocate->IsLinked());
   }
 }
 
 
 } }  // namespace v8::internal