[TurboFan] Reduce zone memory usage in register-allocator-verifier.

src/compiler/register-allocator-verifier.cc

 // Copyright 2014 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 "src/bit-vector.h"
 #include "src/compiler/instruction.h"
 #include "src/compiler/register-allocator-verifier.h"
 
 namespace v8 {
 namespace internal {
@@ skipping 355 matching lines @@
 
 void RegisterAllocatorVerifier::ValidatePendingAssessment(
     RpoNumber block_id, InstructionOperand op,
     BlockAssessments* current_assessments, const PendingAssessment* assessment,
     int virtual_register) {
   // When validating a pending assessment, it is possible some of the
   // assessments
   // for the original operand (the one where the assessment was created for
   // first) are also pending. To avoid recursion, we use a work list. To
   // deal with cycles, we keep a set of seen nodes.
-  ZoneQueue<std::pair<const PendingAssessment*, int>> worklist(zone());
-  ZoneSet<RpoNumber> seen(zone());
+  Zone local_zone(zone()->allocator(), ZONE_NAME);
+  ZoneQueue<std::pair<const PendingAssessment*, int>> worklist(&local_zone);
+  ZoneSet<RpoNumber> seen(&local_zone);
   worklist.push(std::make_pair(assessment, virtual_register));
   seen.insert(block_id);
 
   while (!worklist.empty()) {
     auto work = worklist.front();
     const PendingAssessment* current_assessment = work.first;
     int current_virtual_register = work.second;
     InstructionOperand current_operand = current_assessment->operand();
     worklist.pop();
 
@@ skipping 187 matching lines @@
               new (zone()) FinalAssessment(vreg, pending);
           break;
       }
     }
   }
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8