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C++ iterator::getModule方法代码示例

本文整理汇总了C++中basicblock::iterator::getModule方法的典型用法代码示例。如果您正苦于以下问题:C++ iterator::getModule方法的具体用法?C++ iterator::getModule怎么用?C++ iterator::getModule使用的例子?那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在basicblock::iterator的用法示例。


在下文中一共展示了iterator::getModule方法的1个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的C++代码示例。

示例1: runOnLoop

bool PPCLoopDataPrefetch::runOnLoop(Loop *L) {
  bool MadeChange = false;

  // Only prefetch in the inner-most loop
  if (!L->empty())
    return MadeChange;

  SmallPtrSet<const Value *, 32> EphValues;
  CodeMetrics::collectEphemeralValues(L, AC, EphValues);

  // Calculate the number of iterations ahead to prefetch
  CodeMetrics Metrics;
  for (Loop::block_iterator I = L->block_begin(), IE = L->block_end();
       I != IE; ++I) {

    // If the loop already has prefetches, then assume that the user knows
    // what he or she is doing and don't add any more.
    for (BasicBlock::iterator J = (*I)->begin(), JE = (*I)->end();
         J != JE; ++J)
      if (CallInst *CI = dyn_cast<CallInst>(J))
        if (Function *F = CI->getCalledFunction())
          if (F->getIntrinsicID() == Intrinsic::prefetch)
            return MadeChange;

    Metrics.analyzeBasicBlock(*I, *TTI, EphValues);
  }
  unsigned LoopSize = Metrics.NumInsts;
  if (!LoopSize)
    LoopSize = 1;

  unsigned ItersAhead = PrefDist/LoopSize;
  if (!ItersAhead)
    ItersAhead = 1;

  SmallVector<std::pair<Instruction *, const SCEVAddRecExpr *>, 16> PrefLoads;
  for (Loop::block_iterator I = L->block_begin(), IE = L->block_end();
       I != IE; ++I) {
    for (BasicBlock::iterator J = (*I)->begin(), JE = (*I)->end();
        J != JE; ++J) {
      Value *PtrValue;
      Instruction *MemI;

      if (LoadInst *LMemI = dyn_cast<LoadInst>(J)) {
        MemI = LMemI;
        PtrValue = LMemI->getPointerOperand();
      } else if (StoreInst *SMemI = dyn_cast<StoreInst>(J)) {
        if (!PrefetchWrites) continue;
        MemI = SMemI;
        PtrValue = SMemI->getPointerOperand();
      } else continue;

      unsigned PtrAddrSpace = PtrValue->getType()->getPointerAddressSpace();
      if (PtrAddrSpace)
        continue;

      if (L->isLoopInvariant(PtrValue))
        continue;

      const SCEV *LSCEV = SE->getSCEV(PtrValue);
      const SCEVAddRecExpr *LSCEVAddRec = dyn_cast<SCEVAddRecExpr>(LSCEV);
      if (!LSCEVAddRec)
        continue;

      // We don't want to double prefetch individual cache lines. If this load
      // is known to be within one cache line of some other load that has
      // already been prefetched, then don't prefetch this one as well.
      bool DupPref = false;
      for (SmallVector<std::pair<Instruction *, const SCEVAddRecExpr *>,
             16>::iterator K = PrefLoads.begin(), KE = PrefLoads.end();
           K != KE; ++K) {
        const SCEV *PtrDiff = SE->getMinusSCEV(LSCEVAddRec, K->second);
        if (const SCEVConstant *ConstPtrDiff =
            dyn_cast<SCEVConstant>(PtrDiff)) {
          int64_t PD = std::abs(ConstPtrDiff->getValue()->getSExtValue());
          if (PD < (int64_t) CacheLineSize) {
            DupPref = true;
            break;
          }
        }
      }
      if (DupPref)
        continue;

      const SCEV *NextLSCEV = SE->getAddExpr(LSCEVAddRec, SE->getMulExpr(
        SE->getConstant(LSCEVAddRec->getType(), ItersAhead),
        LSCEVAddRec->getStepRecurrence(*SE)));
      if (!isSafeToExpand(NextLSCEV, *SE))
        continue;

      PrefLoads.push_back(std::make_pair(MemI, LSCEVAddRec));

      Type *I8Ptr = Type::getInt8PtrTy((*I)->getContext(), PtrAddrSpace);
      SCEVExpander SCEVE(*SE, J->getModule()->getDataLayout(), "prefaddr");
      Value *PrefPtrValue = SCEVE.expandCodeFor(NextLSCEV, I8Ptr, MemI);

      IRBuilder<> Builder(MemI);
      Module *M = (*I)->getParent()->getParent();
      Type *I32 = Type::getInt32Ty((*I)->getContext());
      Value *PrefetchFunc = Intrinsic::getDeclaration(M, Intrinsic::prefetch);
      Builder.CreateCall4(PrefetchFunc, PrefPtrValue,
//.........这里部分代码省略.........
开发者ID:Automatic,项目名称:firmware-llvm,代码行数:101,代码来源:PPCLoopDataPrefetch.cpp


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