Subzero: Add a flag to mock up bounds checking on unsafe references.

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.
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
@@ skipping 264 matching lines @@
   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 lowerOther(const Inst *Instr);
 
   virtual void doAddressOptLoad() {}
   virtual void doAddressOptStore() {}
+  virtual void doMockBoundsCheck(Operand *) {}
   virtual void randomlyInsertNop(float Probability,
                                  RandomNumberGenerator &RNG) = 0;
   /// This gives the target an opportunity to post-process the lowered
   /// expansion before returning.
   virtual void postLower() {}
 
   /// Find two-address non-SSA instructions and set the DestNonKillable flag
   /// to keep liveness analysis consistent.
   void inferTwoAddress();
 
@@ skipping 161 matching lines @@
   virtual void lower() {}
 
 protected:
   explicit TargetHeaderLowering(GlobalContext *Ctx) : Ctx(Ctx) {}
   GlobalContext *Ctx;
 };
 
 } // end of namespace Ice
 
 #endif // SUBZERO_SRC_ICETARGETLOWERING_H