diff options
Diffstat (limited to 'lib/Transforms/Utils/LoopSimplify.cpp')
| -rw-r--r-- | lib/Transforms/Utils/LoopSimplify.cpp | 15 |
1 files changed, 9 insertions, 6 deletions
diff --git a/lib/Transforms/Utils/LoopSimplify.cpp b/lib/Transforms/Utils/LoopSimplify.cpp index 76cc32e2a4..1432b1ca62 100644 --- a/lib/Transforms/Utils/LoopSimplify.cpp +++ b/lib/Transforms/Utils/LoopSimplify.cpp @@ -153,14 +153,18 @@ void Preheaders::InsertPreheaderForLoop(Loop *L) { // Update dominator information if it is around... if (DominatorSet *DS = getAnalysisToUpdate<DominatorSet>()) { - // We need to add information about the fact that NewBB dominates Header. - DS->addDominator(Header, NewBB); - // The blocks that dominate NewBB are the blocks that dominate Header, // minus Header, plus NewBB. DominatorSet::DomSetType DomSet = DS->getDominators(Header); + DomSet.insert(NewBB); // We dominate ourself DomSet.erase(Header); // Header does not dominate us... DS->addBasicBlock(NewBB, DomSet); + + // The newly created basic block dominates all nodes dominated by Header. + for (Function::iterator I = Header->getParent()->begin(), + E = Header->getParent()->end(); I != E; ++I) + if (DS->dominates(Header, I)) + DS->addDominator(I, NewBB); } // Update immediate dominator information if we have it... @@ -178,11 +182,10 @@ void Preheaders::InsertPreheaderForLoop(Loop *L) { // the old header. // DominatorTree::Node *HeaderNode = DT->getNode(Header); - DominatorTree::Node *PHNode = DT->createNewNode(NewBB, HeaderNode); + DominatorTree::Node *PHNode = DT->createNewNode(NewBB, + HeaderNode->getIDom()); // Change the header node so that PNHode is the new immediate dominator DT->changeImmediateDominator(HeaderNode, PHNode); } } - - |