Implement bigint shift intrinsics on MIPS.

runtime/vm/intrinsifier_arm.cc

 // 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.
 
 #include "vm/globals.h"  // Needed here to get TARGET_ARCH_ARM.
 #if defined(TARGET_ARCH_ARM)
 
 #include "vm/intrinsifier.h"
 
 #include "vm/assembler.h"
@@ skipping 857 matching lines @@
   __ b(&loop_entry);
   Label loop;
   __ Bind(&loop);
   __ ldr(R0, Address(R7, Bigint::kBytesPerDigit, Address::PostIndex));
   __ orr(R1, R1, Operand(R0, LSL, R2));
   __ str(R1, Address(R8, Bigint::kBytesPerDigit, Address::PostIndex));
   __ mov(R1, Operand(R0, LSR, R3));
   __ Bind(&loop_entry);
   __ teq(R8, Operand(R6));
   __ b(&loop, NE);
-  __ str(R1, Address(R8, Bigint::kBytesPerDigit, Address::PostIndex));
+  __ str(R1, Address(R8, 0));
   // Returning Object::null() is not required, since this method is private.
   __ Ret();
 }
 
 
 void Intrinsifier::Bigint_absAdd(Assembler* assembler) {
   // static void _absAdd(Uint32List digits, int used,
   //                     Uint32List a_digits, int a_used,
   //                     Uint32List r_digits)
 
@@ skipping 1132 matching lines @@
   Isolate* isolate = Isolate::Current();
   __ LoadImmediate(R1, reinterpret_cast<uword>(isolate));
   // Set return value to Isolate::current_tag_.
   __ ldr(R0, Address(R1, Isolate::current_tag_offset()));
   __ Ret();
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_ARM