本文整理汇总了C++中machinebasicblock::const_iterator::operands_begin方法的典型用法代码示例。如果您正苦于以下问题：C++ const_iterator::operands_begin方法的具体用法？C++ const_iterator::operands_begin怎么用？C++ const_iterator::operands_begin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::const_iterator的用法示例。
在下文中一共展示了const_iterator::operands_begin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: runOnMachineFunction
bool VirtRegReduction::runOnMachineFunction(MachineFunction &MF)
{
bool Changed = false;
#if VRRPROF
const Function *F = MF.getFunction();
std::string FN = F->getName().str();
llog("starting vrr... %s (%d)\n", FN.c_str(), (int)time(NULL));
llog("starting immRegs finder... (%d)\n", (int)time(NULL));
#endif
std::auto_ptr<std::unordered_set<unsigned> > immRegsHolder;
std::unordered_set<unsigned> *immRegs = NULL;
// single-def regs defined by a MoveImm shouldn't coalesce as we may be
// able to fold them later
{
std::unordered_map<unsigned, const MachineInstr *> singleDef;
MachineFunction::const_iterator I = MF.begin(), E = MF.end();
// find all registers w/ a single def
for(; I != E; I++)
{
MachineBasicBlock::const_iterator BI = I->begin(), BE = I->end();
for(; BI != BE; BI++)
{
MachineInstr::const_mop_iterator II, IE;
II = BI->operands_begin();
IE = BI->operands_end();
for(; II != IE; II++)
if(II->isReg() && II->isDef())
{
unsigned R = II->getReg();
std::unordered_map<unsigned, const MachineInstr *>::iterator SI = singleDef.find(R);
if(SI == singleDef.end())
singleDef[R] = BI; // first seen! insert
else
SI->second = NULL; // second seen -- replace w/ NULL
}
}
}
std::unordered_map<unsigned, const MachineInstr *>::const_iterator SI = singleDef.begin(), SE = singleDef.end();
for(; SI != SE; SI++)
{
if(SI->second && SI->second->getDesc().isMoveImmediate()) // single def imm?
{
if(!immRegs)
immRegsHolder.reset(immRegs = new std::unordered_set<unsigned>);
immRegs->insert(SI->first); // don't coalesce
}
}
}
#if VRRPROF
llog("starting tdkRegs finder... (%d)\n", (int)time(NULL));
#endif
std::auto_ptr<std::unordered_set<unsigned> > tdkRegsHolder;
std::unordered_set<unsigned> *tdkRegs = NULL;
bool setjmpSafe = !MF.callsSetJmp() && MF.getFunction()->doesNotThrow();
{
tdkRegsHolder.reset(tdkRegs = new std::unordered_set<unsigned>);
std::unordered_map<unsigned, unsigned> trivialDefKills;
MachineFunction::const_iterator I = MF.begin(), E = MF.end();
// find all registers defed and killed in the same block w/ no intervening
// unsafe (due to setjmp) calls + side-effecty operations
for(; I != E; I++)
{
std::unordered_set<unsigned> defs;
MachineBasicBlock::const_iterator BI = I->begin(), BE = I->end();
for(; BI != BE; BI++)
{
// TODO need to add || BI->getDesc().isInlineAsm() here to help stackification?
if((!setjmpSafe && BI->getDesc().isCall()) || BI->getDesc().hasUnmodeledSideEffects()) {
// invalidate on a call instruction if setjmp present, or instr with side effects regardless
defs.clear();
}
MachineInstr::const_mop_iterator II, IE;
// uses when we're not tracking a reg it make it unsafe
II = BI->operands_begin();
IE = BI->operands_end();
for(; II != IE; II++)
if(II->isReg() && II->isUse())
{
unsigned R = II->getReg();
std::unordered_set<unsigned>::const_iterator DI = defs.find(R);
//.........这里部分代码省略.........