Reuse ZoneList memory if possible.

src/hydrogen-escape-analysis.cc

 // Copyright 2013 the V8 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.
 
 #include "hydrogen-escape-analysis.h"
 
 namespace v8 {
 namespace internal {
 
 
@@ skipping 281 matching lines @@
 
 
 void HEscapeAnalysisPhase::PerformScalarReplacement() {
   for (int i = 0; i < captured_.length(); i++) {
     HAllocate* allocate = HAllocate::cast(captured_.at(i));
 
     // Compute number of scalar values and start with clean slate.
     int size_in_bytes = allocate->size()->GetInteger32Constant();
     number_of_values_ = size_in_bytes / kPointerSize;
     number_of_objects_++;
-    block_states_.Clear();
+    block_states_.Rewind(0);
 
     // Perform actual analysis step.
     AnalyzeDataFlow(allocate);
 
     cumulative_values_ += number_of_values_;
     ASSERT(allocate->HasNoUses());
     ASSERT(!allocate->IsLinked());
   }
 }
 
 
 void HEscapeAnalysisPhase::Run() {
   // TODO(mstarzinger): We disable escape analysis with OSR for now, because
   // spill slots might be uninitialized. Needs investigation.
   if (graph()->has_osr()) return;
   int max_fixpoint_iteration_count = FLAG_escape_analysis_iterations;
   for (int i = 0; i < max_fixpoint_iteration_count; i++) {
     CollectCapturedValues();
     if (captured_.is_empty()) break;
     PerformScalarReplacement();
-    captured_.Clear();
+    captured_.Rewind(0);
   }
 }
 
 
 } }  // namespace v8::internal