Subzero: Use CFG-local arena allocation for relevant containers.

src/assembler.h

 //===- subzero/src/assembler.h - Integrated assembler -----------*- C++ -*-===//
 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 //
 // Modified by the Subzero authors.
 //
 //===----------------------------------------------------------------------===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file declares the Assembler base class.  Instructions are assembled
 // by architecture-specific assemblers that derive from this base class.
 // This base class manages buffers and fixups for emitting code, etc.
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef SUBZERO_SRC_ASSEMBLER_H
 #define SUBZERO_SRC_ASSEMBLER_H
 
 #include "IceDefs.h"
-
 #include "IceFixups.h"
-#include "llvm/Support/Allocator.h"
 
 namespace Ice {
 
 // Forward declarations.
 class Assembler;
 class AssemblerFixup;
 class AssemblerBuffer;
 class ConstantRelocatable;
 
 // Assembler fixups are positions in generated code that hold relocation
@@ skipping 185 matching lines @@
   // Mark the current text location as the start of a CFG node
   // (represented by NodeNumber).
   virtual void BindCfgNodeLabel(SizeT NodeNumber) = 0;
 
   // Return a view of all the bytes of code for the current function.
   llvm::StringRef getBufferView() const;
 
   void emitIASBytes(GlobalContext *Ctx) const;
 
 private:
-  llvm::BumpPtrAllocator Allocator;
+  ArenaAllocator Allocator;
 
 protected:
   AssemblerBuffer buffer_;
 };
 
 } // end of namespace Ice
 
 #endif // SUBZERO_SRC_ASSEMBLER_H_