Selectively invert ICMP operands for better address optimization

src/IceInst.h

Index: src/IceInst.h
diff --git a/src/IceInst.h b/src/IceInst.h
index 029fcc59079c01a76f76b9567d8477ac70331945..ff2b81d35b52bdbe41b18c339a41dc7f3ff3dc74 100644
--- a/src/IceInst.h
+++ b/src/IceInst.h
@@ -550,6 +550,7 @@ public:
         InstIcmp(Func, Condition, Dest, Source1, Source2);
   }
   ICond getCondition() const { return Condition; }
+  void invert();

[Jim Stichnoth, 2016/07/08 11:45:46]

How about invertCondition()?

Otherwise my default reading would be that it is supposed to "invert" the
*instruction*, which is less clear.

[manasijm, 2016/07/08 18:11:40]

Done.

   bool isMemoryWrite() const override { return false; }
   void dump(const Cfg *Func) const override;
   static bool classof(const Inst *Instr) { return Instr->getKind() == Icmp; }
@@ -558,7 +559,7 @@ private:
   InstIcmp(Cfg *Func, ICond Condition, Variable *Dest, Operand *Source1,
            Operand *Source2);
 
-  const ICond Condition;
+  ICond Condition;
 };
 
 /// InsertElement instruction.