Subzero: Randomly insert nops.

src/IceTargetLoweringX8632.h

 //===- subzero/src/IceTargetLoweringX8632.h - x86-32 lowering ---*- 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 TargetLoweringX8632 class, which
@@ skipping 86 matching lines @@
   virtual void lowerInsertElement(const InstInsertElement *Inst);
   virtual void lowerLoad(const InstLoad *Inst);
   virtual void lowerPhi(const InstPhi *Inst);
   virtual void lowerRet(const InstRet *Inst);
   virtual void lowerSelect(const InstSelect *Inst);
   virtual void lowerStore(const InstStore *Inst);
   virtual void lowerSwitch(const InstSwitch *Inst);
   virtual void lowerUnreachable(const InstUnreachable *Inst);
   virtual void doAddressOptLoad();
   virtual void doAddressOptStore();
+  virtual void randomlyInsertNop(float Probability);
 
   // Naive lowering of cmpxchg.
   void lowerAtomicCmpxchg(Variable *DestPrev, Operand *Ptr, Operand *Expected,
                           Operand *Desired);
   // Attempt a more optimized lowering of cmpxchg. Returns true if optimized.
   bool tryOptimizedCmpxchgCmpBr(Variable *DestPrev, Operand *Ptr,
                                 Operand *Expected, Operand *Desired);
   void lowerAtomicRMW(Variable *Dest, uint32_t Operation, Operand *Ptr,
                       Operand *Val);
   void lowerCountZeros(bool Cttz, Type Ty, Variable *Dest, Operand *FirstVal,
@@ skipping 201 matching lines @@
   }
   void _mulps(Variable *Dest, Operand *Src0) {
     Context.insert(InstX8632Mulps::create(Func, Dest, Src0));
   }
   void _mulss(Variable *Dest, Operand *Src0) {
     Context.insert(InstX8632Mulss::create(Func, Dest, Src0));
   }
   void _neg(Variable *SrcDest) {
     Context.insert(InstX8632Neg::create(Func, SrcDest));
   }
+  void _nop(SizeT Length = 1) {
+    Context.insert(InstX8632Nop::create(Func, Length));
+  }
   void _or(Variable *Dest, Operand *Src0) {
     Context.insert(InstX8632Or::create(Func, Dest, Src0));
   }
   void _padd(Variable *Dest, Operand *Src0) {
     Context.insert(InstX8632Padd::create(Func, Dest, Src0));
   }
   void _pand(Variable *Dest, Operand *Src0) {
     Context.insert(InstX8632Pand::create(Func, Dest, Src0));
   }
   void _pandn(Variable *Dest, Operand *Src0) {
@@ skipping 155 matching lines @@
   virtual ~TargetGlobalInitX8632() {}
 };
 
 template <> void ConstantInteger::emit(GlobalContext *Ctx) const;
 template <> void ConstantFloat::emit(GlobalContext *Ctx) const;
 template <> void ConstantDouble::emit(GlobalContext *Ctx) const;
 
 } // end of namespace Ice
 
 #endif // SUBZERO_SRC_ICETARGETLOWERINGX8632_H