ARM: Don't generate memory instructions with writeback where the data and address registers are the…

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 303 matching lines @@
   }
 
   Register rm() const {
     return ((kind() == IndexRegister) || (kind() == ScaledIndexRegister)) ?
         Instr::At(reinterpret_cast<uword>(&encoding_))->RmField() :
         kNoRegister;
   }
 
   Mode mode() const { return static_cast<Mode>(encoding() & kModeMask); }
 
+  bool has_writeback() const {
+    return (mode() == PreIndex) || (mode() == PostIndex) ||
+           (mode() == NegPreIndex) || (mode() == NegPostIndex);
+  }
+
   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;
 
   OffsetKind kind() const { return kind_; }
 
@@ skipping 871 matching lines @@
                      Register new_value,
                      FieldContent old_content);
 
   DISALLOW_ALLOCATION();
   DISALLOW_COPY_AND_ASSIGN(Assembler);
 };
 
 }  // namespace dart
 
 #endif  // VM_ASSEMBLER_ARM_H_