Add various forms of LDREX/STREX to ARM integrated assembler.

src/DartARM32/assembler_arm.h

 // Copyright (c) 2013, 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.
 //
 // This is forked from Dart revision df52deea9f25690eb8b66c5995da92b70f7ac1fe
 // Please update the (git) revision if we merge changes from Dart.
 // https://code.google.com/p/dart/wiki/GettingTheSource
 
 #ifndef VM_ASSEMBLER_ARM_H_
 #define VM_ASSEMBLER_ARM_H_
@@ skipping 570 matching lines @@
 #if 0
   // Folded into ARM32::AssemblerARM32::popList(), since it is its only use (and
   // doesn't implement ARM LDM instructions).
   void ldm(BlockAddressMode am, Register base,
            RegList regs, Condition cond = AL);
 
   // Folded into ARM32::AssemblerARM32::pushList(), since it is its only use
   // (and doesn't implement ARM STM instruction).
   void stm(BlockAddressMode am, Register base,
            RegList regs, Condition cond = AL);
+
+  // Moved to ARM::AssemblerARM32::ldrex();
+  void ldrex(Register rd, Register rn, Condition cond = AL);
+  // Moved to ARM::AssemblerARM32::strex();
+  void strex(Register rd, Register rt, Register rn, Condition cond = AL);
 #endif
 
-  void ldrex(Register rd, Register rn, Condition cond = AL);
-  void strex(Register rd, Register rt, Register rn, Condition cond = AL);
-
   // Miscellaneous instructions.
   void clrex();
 #if 0
   // Moved to ARM32::AssemblerARM32::nop().
   void nop(Condition cond = AL);
 
   // Moved to ARM32::AssemblerARM32::bkpt()
   // Note that gdb sets breakpoints using the undefined instruction 0xe7f001f0.
   void bkpt(uint16_t imm16);
 
@@ skipping 715 matching lines @@
   // ARM32::AssemblerARM::uxt() (uxtb and uxth).
 #endif
 
   DISALLOW_ALLOCATION();
   DISALLOW_COPY_AND_ASSIGN(Assembler);
 };
 
 }  // namespace dart
 
 #endif  // VM_ASSEMBLER_ARM_H_