Preserve the DominanceFrontier analysis in the LoopDeletion pass.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65359 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Dan Gohman 2009-02-24 01:21:53 +00:00
parent 002ec1482c
commit d0a90b9876

View File

@ -53,6 +53,7 @@ namespace {
AU.addPreserved<LoopInfo>();
AU.addPreservedID(LoopSimplifyID);
AU.addPreservedID(LCSSAID);
AU.addPreserved<DominanceFrontier>();
}
};
}
@ -228,6 +229,7 @@ bool LoopDeletion::runOnLoop(Loop* L, LPPassManager& LPM) {
// Update the dominator tree and remove the instructions and blocks that will
// be deleted from the reference counting scheme.
DominatorTree& DT = getAnalysis<DominatorTree>();
DominanceFrontier* DF = getAnalysisIfAvailable<DominanceFrontier>();
SmallPtrSet<DomTreeNode*, 8> ChildNodes;
for (Loop::block_iterator LI = L->block_begin(), LE = L->block_end();
LI != LE; ++LI) {
@ -235,12 +237,15 @@ bool LoopDeletion::runOnLoop(Loop* L, LPPassManager& LPM) {
// allows us to remove the domtree entry for the block.
ChildNodes.insert(DT[*LI]->begin(), DT[*LI]->end());
for (SmallPtrSet<DomTreeNode*, 8>::iterator DI = ChildNodes.begin(),
DE = ChildNodes.end(); DI != DE; ++DI)
DE = ChildNodes.end(); DI != DE; ++DI) {
DT.changeImmediateDominator(*DI, DT[preheader]);
if (DF) DF->changeImmediateDominator((*DI)->getBlock(), preheader, &DT);
}
ChildNodes.clear();
DT.eraseNode(*LI);
if (DF) DF->removeBlock(*LI);
// Remove instructions that we're deleting from ScalarEvolution.
for (BasicBlock::iterator BI = (*LI)->begin(), BE = (*LI)->end();
BI != BE; ++BI)