/// \brief Determine the end of the loops
void StructurizeCFG::analyzeLoops(RegionNode *N) {
if (N->isSubRegion()) {
// Test for exit as back edge
BasicBlock *Exit = N->getNodeAs<Region>()->getExit();
if (Visited.count(Exit))
Loops[Exit] = N->getEntry();
} else {
// Test for sucessors as back edge
BasicBlock *BB = N->getNodeAs<BasicBlock>();
BranchInst *Term = cast<BranchInst>(BB->getTerminator());
for (BasicBlock *Succ : Term->successors())
if (Visited.count(Succ))
Loops[Succ] = BB;
}
}
bool IRTranslator::translateBr(const BranchInst &BrInst) {
unsigned Succ = 0;
if (!BrInst.isUnconditional()) {
// We want a G_BRCOND to the true BB followed by an unconditional branch.
unsigned Tst = getOrCreateVReg(*BrInst.getCondition());
const BasicBlock &TrueTgt = *cast<BasicBlock>(BrInst.getSuccessor(Succ++));
MachineBasicBlock &TrueBB = getOrCreateBB(TrueTgt);
MIRBuilder.buildBrCond(LLT{*BrInst.getCondition()->getType()}, Tst, TrueBB);
}
const BasicBlock &BrTgt = *cast<BasicBlock>(BrInst.getSuccessor(Succ));
MachineBasicBlock &TgtBB = getOrCreateBB(BrTgt);
MIRBuilder.buildBr(TgtBB);
// Link successors.
MachineBasicBlock &CurBB = MIRBuilder.getMBB();
for (const BasicBlock *Succ : BrInst.successors())
CurBB.addSuccessor(&getOrCreateBB(*Succ));
return true;
}
