本文整理汇总了C++中machinebasicblock::iterator::findFirstPredOperandIdx方法的典型用法代码示例。如果您正苦于以下问题：C++ iterator::findFirstPredOperandIdx方法的具体用法？C++ iterator::findFirstPredOperandIdx怎么用？C++ iterator::findFirstPredOperandIdx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类machinebasicblock::iterator的用法示例。
在下文中一共展示了iterator::findFirstPredOperandIdx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: AnalyzeBranch
bool PatmosInstrInfo::AnalyzeBranch(MachineBasicBlock &MBB,
MachineBasicBlock *&TBB,
MachineBasicBlock *&FBB,
SmallVectorImpl<MachineOperand> &Cond,
bool AllowModify) const {
// If the client does not want to only simplify the branch,
// the output arguments must be initialized.
assert(AllowModify || (TBB==0 && FBB==0 && Cond.size()==0));
// Start from the bottom of the block and work up, examining the
// terminator instructions.
MachineBasicBlock::iterator I = MBB.end();
while (I != MBB.begin()) {
--I;
if (I->isDebugValue() || I->isPseudo())
continue;
// Working from the bottom, when we see a non-terminator inst, we're done.
if (!isUnpredicatedTerminator(I))
break;
// A terminator that isn't a (direct) branch can't easily be handled
// by this analysis.
if (!I->isBranch() || I->isIndirectBranch())
return true;
// Handle Unconditional branches
if (!isPredicated(I)) {
// fix instruction, if necessary
if (!I->isUnconditionalBranch()) fixOpcodeForGuard(I);
// TBB is used to indicate the unconditional destination.
TBB = getBranchTarget(I);
if (AllowModify) {
// If the block has any instructions after an uncond branch, delete them.
while (llvm::next(I) != MBB.end())
llvm::next(I)->eraseFromParent();
}
continue;
}
// Handle conditional branches
if (isPredicated(I)) {
// fix instruction, if necessary
if (!I->isConditionalBranch()) fixOpcodeForGuard(I);
// we only treat the first conditional branch in a row
if (Cond.size() > 0)
return true;
// Get branch condition
int i = I->findFirstPredOperandIdx();
assert(i != -1 );
Cond.push_back(I->getOperand(i)); // reg
Cond.push_back(I->getOperand(i+1)); // flag
// We've processed an unconditional branch before,
// the unconditional target goes to FBB now
if (TBB) FBB = TBB;
// target of conditional branch goes to TBB
TBB = getBranchTarget(I);
continue;
}
// we explicitly leave or continue.
llvm_unreachable("AnalyzeBranch error.");
}
// left the loop? then we're done
return false;
}