Subzero, MIPS32: Randomly insert NOP

src/IceTargetLoweringMIPS32.cpp

 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
 /// \brief Implements the TargetLoweringMIPS32 class, which consists almost
@@ skipping 3178 matching lines @@
           formAddressingMode(Dest->getType(), Func, Instr, Addr)) {
     Instr->setDeleted();
     Context.insert<InstLoad>(Dest, Mem);
   }
 }
 
 void TargetMIPS32::randomlyInsertNop(float Probability,
                                      RandomNumberGenerator &RNG) {
   RandomNumberGeneratorWrapper RNGW(RNG);
   if (RNGW.getTrueWithProbability(Probability)) {
-    UnimplementedError(getFlags());
+    _nop();
   }
 }
 
 void TargetMIPS32::lowerPhi(const InstPhi * /*Instr*/) {
   Func->setError("Phi found in regular instruction list");
 }
 
 void TargetMIPS32::lowerRet(const InstRet *Instr) {
   Variable *Reg = nullptr;
   if (Instr->hasRetValue()) {
@@ skipping 457 matching lines @@
   Str << "\t.set\t"
       << "nomips16\n";
 }
 
 SmallBitVector TargetMIPS32::TypeToRegisterSet[RCMIPS32_NUM];
 SmallBitVector TargetMIPS32::TypeToRegisterSetUnfiltered[RCMIPS32_NUM];
 SmallBitVector TargetMIPS32::RegisterAliases[RegMIPS32::Reg_NUM];
 
 } // end of namespace MIPS32
 } // end of namespace Ice