A64: Add support for SMI representation to MulConstI. Also add a test.

src/a64/lithium-codegen-a64.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
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 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
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@@ skipping 4100 matching lines @@
         __ Tbnz(dividend, kWSignBit, &deopt);
       } else {
         DeoptimizeIfNegative(dividend, instr->environment());
       }
     }
   }
   __ Bind(&done);
 }
 
 
-void LCodeGen::DoMulConstI(LMulConstI* instr) {
-  // TODO(jbramley): Support smi operations (or make a separate DoMulConstS).
-
-  Register result = ToRegister32(instr->result());
-  Register left = ToRegister32(instr->left());
+void LCodeGen::DoMulConstIS(LMulConstIS* instr) {
+  ASSERT(instr->hydrogen()->representation().IsSmiOrInteger32());
+  bool is_smi = instr->hydrogen()->representation().IsSmi();
+  Register result =
+      is_smi ? ToRegister(instr->result()) : ToRegister32(instr->result());
+  Register left =
+      is_smi ? ToRegister(instr->left()) : ToRegister32(instr->left()) ;
   int32_t right = ToInteger32(instr->right());
 
   bool can_overflow = instr->hydrogen()->CheckFlag(HValue::kCanOverflow);
   bool bailout_on_minus_zero =
     instr->hydrogen()->CheckFlag(HValue::kBailoutOnMinusZero);
 
   if (bailout_on_minus_zero) {
     if (right < 0) {
       // The result is -0 if right is negative and left is zero.
       DeoptimizeIfZero(left, instr->environment());
@@ skipping 1442 matching lines @@
   __ Bind(&out_of_object);
   __ Ldr(result, FieldMemOperand(object, JSObject::kPropertiesOffset));
   // Index is equal to negated out of object property index plus 1.
   __ Sub(result, result, Operand::UntagSmiAndScale(index, kPointerSizeLog2));
   __ Ldr(result, FieldMemOperand(result,
                                  FixedArray::kHeaderSize - kPointerSize));
   __ Bind(&done);
 }
 
 } }  // namespace v8::internal