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C++ ConstantExpr::getAsInstruction方法代码示例

本文整理汇总了C++中ConstantExpr::getAsInstruction方法的典型用法代码示例。如果您正苦于以下问题:C++ ConstantExpr::getAsInstruction方法的具体用法?C++ ConstantExpr::getAsInstruction怎么用?C++ ConstantExpr::getAsInstruction使用的例子?那么, 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ConstantExpr的用法示例。


在下文中一共展示了ConstantExpr::getAsInstruction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: EmitBaseConstants

/// \brief Emit materialization code for all rebased constants and update their
/// users.
void ConstantHoisting::EmitBaseConstants(Function &F, User *U,
                                         Instruction *Base, Constant *Offset,
                                         ConstantInt *OriginalConstant) {
  if (Instruction *I = dyn_cast<Instruction>(U)) {
    Instruction *Mat = Base;
    if (!Offset->isNullValue()) {
      Mat = BinaryOperator::Create(Instruction::Add, Base, Offset,
                                   "const_mat", getMatInsertPt(I, DT));

      // Use the same debug location as the instruction we are about to update.
      Mat->setDebugLoc(I->getDebugLoc());

      DEBUG(dbgs() << "Materialize constant (" << *Base->getOperand(0)
                   << " + " << *Offset << ") in BB "
                   << I->getParent()->getName() << '\n' << *Mat << '\n');
    }
    DEBUG(dbgs() << "Update: " << *I << '\n');
    I->replaceUsesOfWith(OriginalConstant, Mat);
    DEBUG(dbgs() << "To: " << *I << '\n');
    return;
  }
  assert(isa<ConstantExpr>(U) && "Expected a ConstantExpr.");
  ConstantExpr *CE = cast<ConstantExpr>(U);
  for (Value::use_iterator UU = CE->use_begin(), E = CE->use_end();
       UU != E; ++UU) {
    // We only handel instructions here and won't walk down a ConstantExpr chain
    // to replace all ConstExpr with instructions.
    if (Instruction *I = dyn_cast<Instruction>(*UU)) {
      // Only update constant expressions in the current function.
      if (I->getParent()->getParent() != &F)
        continue;

      Instruction *Mat = Base;
      Instruction *InsertBefore = getMatInsertPt(I, DT);
      if (!Offset->isNullValue()) {
        Mat = BinaryOperator::Create(Instruction::Add, Base, Offset,
                                     "const_mat", InsertBefore);

        // Use the same debug location as the instruction we are about to
        // update.
        Mat->setDebugLoc(I->getDebugLoc());

        DEBUG(dbgs() << "Materialize constant (" << *Base->getOperand(0)
                     << " + " << *Offset << ") in BB "
                     << I->getParent()->getName() << '\n' << *Mat << '\n');
      }
      Instruction *ICE = CE->getAsInstruction();
      ICE->replaceUsesOfWith(OriginalConstant, Mat);
      ICE->insertBefore(InsertBefore);

      // Use the same debug location as the instruction we are about to update.
      ICE->setDebugLoc(I->getDebugLoc());

      DEBUG(dbgs() << "Create instruction: " << *ICE << '\n');
      DEBUG(dbgs() << "Update: " << *I << '\n');
      I->replaceUsesOfWith(CE, ICE);
      DEBUG(dbgs() << "To: " << *I << '\n');
    }
  }
}
开发者ID:Xmister,项目名称:llvm-onex,代码行数:62,代码来源:ConstantHoisting.cpp


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