Bias commutative single-use register inputs and support lea adds

src/ia32/lithium-ia32.h

Index: src/ia32/lithium-ia32.h
diff --git a/src/ia32/lithium-ia32.h b/src/ia32/lithium-ia32.h
index 062744ad9440cd9eb6462800d47be969777353b7..f5da47c7f64c325ad65f43e477086749f4d9d516 100644
--- a/src/ia32/lithium-ia32.h
+++ b/src/ia32/lithium-ia32.h
@@ -1369,6 +1369,11 @@ class LAddI: public LTemplateInstruction<1, 2, 0> {
   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)
 };