Clean up ARM assembly code loading and storing from/to a large offset.

runtime/vm/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.
 
 #ifndef VM_ASSEMBLER_ARM_H_
 #define VM_ASSEMBLER_ARM_H_
 
 #ifndef VM_ASSEMBLER_H_
 #error Do not include assembler_arm.h directly; use assembler.h instead.
 #endif
@@ skipping 241 matching lines @@
   }
 
   explicit Address(Register rn, Register rm, Shift shift = LSL,
                    uint32_t shift_imm = 0, Mode am = Offset) {
     ShifterOperand so(rm, shift, shift_imm);
 
     kind_ = ShiftedRegister;
     encoding_ = so.encoding() | am | (static_cast<uint32_t>(rn) << kRnShift);
   }
 
-  static bool CanHoldLoadOffset(LoadOperandType type, int offset);
-  static bool CanHoldStoreOffset(StoreOperandType type, int offset);
+  static bool CanHoldLoadOffset(LoadOperandType type,
+                                int32_t offset,
+                                int32_t* offset_mask);
+  static bool CanHoldStoreOffset(StoreOperandType type,
+                                 int32_t offset,
+                                 int32_t* offset_mask);
 
  private:
   uint32_t encoding() const { return encoding_; }
 
   // Encoding for addressing mode 3.
   uint32_t encoding3() const;
 
   // Encoding for vfp load/store addressing.
   uint32_t vencoding() const;
 
@@ skipping 490 matching lines @@
     return *reg1 - *reg2;
   }
 
   DISALLOW_ALLOCATION();
   DISALLOW_COPY_AND_ASSIGN(Assembler);
 };
 
 }  // namespace dart
 
 #endif  // VM_ASSEMBLER_ARM_H_