Bias commutative single-use register inputs and support lea adds

src/x64/lithium-x64.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 1327 matching lines @@
 class LAddI: public LTemplateInstruction<1, 2, 0> {
  public:
   LAddI(LOperand* left, LOperand* right) {
     inputs_[0] = left;
     inputs_[1] = right;
   }
 
   LOperand* left() { return inputs_[0]; }
   LOperand* right() { return inputs_[1]; }
 
+  static bool UseLea(HAdd* add) {
+    return !add->CheckFlag(HValue::kCanOverflow) &&
+        add->BetterLeftOperand()->UseCount() > 1;
+  }
+
   DECLARE_CONCRETE_INSTRUCTION(AddI, "add-i")
   DECLARE_HYDROGEN_ACCESSOR(Add)
 };
 
 
 class LMathMinMax: public LTemplateInstruction<1, 2, 0> {
  public:
   LMathMinMax(LOperand* left, LOperand* right) {
     inputs_[0] = left;
     inputs_[1] = right;
@@ skipping 1383 matching lines @@
 
   DISALLOW_COPY_AND_ASSIGN(LChunkBuilder);
 };
 
 #undef DECLARE_HYDROGEN_ACCESSOR
 #undef DECLARE_CONCRETE_INSTRUCTION
 
 } }  // namespace v8::int
 
 #endif  // V8_X64_LITHIUM_X64_H_