Use the new MergeBasicBlockIntoOnlyPred function.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60163 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2008-11-27 07:54:12 +00:00
parent b29714a10a
commit 3c4f8b91ef

View File

@ -205,25 +205,7 @@ void CodeGenPrepare::EliminateMostlyEmptyBlock(BasicBlock *BB) {
// If the destination block has a single pred, then this is a trivial edge,
// just collapse it.
if (DestBB->getSinglePredecessor()) {
// If DestBB has single-entry PHI nodes, fold them.
while (PHINode *PN = dyn_cast<PHINode>(DestBB->begin())) {
Value *NewVal = PN->getIncomingValue(0);
// Replace self referencing PHI with undef, it must be dead.
if (NewVal == PN) NewVal = UndefValue::get(PN->getType());
PN->replaceAllUsesWith(NewVal);
PN->eraseFromParent();
}
// Splice all the PHI nodes from BB over to DestBB.
DestBB->getInstList().splice(DestBB->begin(), BB->getInstList(),
BB->begin(), BI);
// Anything that branched to BB now branches to DestBB.
BB->replaceAllUsesWith(DestBB);
// Nuke BB.
BB->eraseFromParent();
MergeBasicBlockIntoOnlyPred(DestBB);
DOUT << "AFTER:\n" << *DestBB << "\n\n\n";
return;
}