Subzero: Initial O2 lowering

src/IceTargetLowering.h

 //===- subzero/src/IceTargetLowering.h - Lowering interface -----*- C++ -*-===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file declares the TargetLowering and LoweringContext
@@ skipping 91 matching lines @@
   virtual void translateO0() {
     Func->setError("Target doesn't specify O0 lowering steps.");
   }
   virtual void translateO1() {
     Func->setError("Target doesn't specify O1 lowering steps.");
   }
   virtual void translateO2() {
     Func->setError("Target doesn't specify O2 lowering steps.");
   }
 
+  // Tries to do address mode optimization on a single instruction.
+  void doAddressOpt();
   // Lowers a single instruction.
   void lower();
 
   // Returns a variable pre-colored to the specified physical
   // register.  This is generally used to get very direct access to
   // the register such as in the prolog or epilog or for marking
   // scratch registers as killed by a call.
   virtual Variable *getPhysicalRegister(SizeT RegNum) = 0;
   // Returns a printable name for the register.
   virtual IceString getRegName(SizeT RegNum, Type Ty) const = 0;
@@ skipping 44 matching lines @@
   virtual void lowerFcmp(const InstFcmp *Inst) = 0;
   virtual void lowerIcmp(const InstIcmp *Inst) = 0;
   virtual void lowerLoad(const InstLoad *Inst) = 0;
   virtual void lowerPhi(const InstPhi *Inst) = 0;
   virtual void lowerRet(const InstRet *Inst) = 0;
   virtual void lowerSelect(const InstSelect *Inst) = 0;
   virtual void lowerStore(const InstStore *Inst) = 0;
   virtual void lowerSwitch(const InstSwitch *Inst) = 0;
   virtual void lowerUnreachable(const InstUnreachable *Inst) = 0;
 
+  virtual void doAddressOptLoad() {}
+  virtual void doAddressOptStore() {}
   // This gives the target an opportunity to post-process the lowered
   // expansion before returning.  The primary intention is to do some
   // Register Manager activity as necessary, specifically to eagerly
   // allocate registers based on affinity and other factors.  The
   // simplest lowering does nothing here and leaves it all to a
   // subsequent global register allocation pass.
   virtual void postLower() {}
 
   Cfg *Func;
   GlobalContext *Ctx;
   bool HasComputedFrame;
   // StackAdjustment keeps track of the current stack offset from its
   // natural location, as arguments are pushed for a function call.
   int32_t StackAdjustment;
   LoweringContext Context;
 
 private:
   TargetLowering(const TargetLowering &) LLVM_DELETED_FUNCTION;
   TargetLowering &operator=(const TargetLowering &) LLVM_DELETED_FUNCTION;
 };
 
 } // end of namespace Ice
 
 #endif // SUBZERO_SRC_ICETARGETLOWERING_H