diff options
Diffstat (limited to 'lib/Transforms/Utils/Local.cpp')
| -rw-r--r-- | lib/Transforms/Utils/Local.cpp | 24 |
1 files changed, 13 insertions, 11 deletions
diff --git a/lib/Transforms/Utils/Local.cpp b/lib/Transforms/Utils/Local.cpp index 506e5e8..0f6d9ae 100644 --- a/lib/Transforms/Utils/Local.cpp +++ b/lib/Transforms/Utils/Local.cpp @@ -536,9 +536,9 @@ static bool CanPropagatePredecessorsForPHIs(BasicBlock *BB, BasicBlock *Succ) { /// TryToSimplifyUncondBranchFromEmptyBlock - BB is known to contain an /// unconditional branch, and contains no instructions other than PHI nodes, -/// potential debug intrinsics and the branch. If possible, eliminate BB by -/// rewriting all the predecessors to branch to the successor block and return -/// true. If we can't transform, return false. +/// potential side-effect free intrinsics and the branch. If possible, +/// eliminate BB by rewriting all the predecessors to branch to the successor +/// block and return true. If we can't transform, return false. bool llvm::TryToSimplifyUncondBranchFromEmptyBlock(BasicBlock *BB) { assert(BB != &BB->getParent()->getEntryBlock() && "TryToSimplifyUncondBranchFromEmptyBlock called on entry block!"); @@ -613,13 +613,15 @@ bool llvm::TryToSimplifyUncondBranchFromEmptyBlock(BasicBlock *BB) { } } - while (PHINode *PN = dyn_cast<PHINode>(&BB->front())) { - if (Succ->getSinglePredecessor()) { - // BB is the only predecessor of Succ, so Succ will end up with exactly - // the same predecessors BB had. - Succ->getInstList().splice(Succ->begin(), - BB->getInstList(), BB->begin()); - } else { + if (Succ->getSinglePredecessor()) { + // BB is the only predecessor of Succ, so Succ will end up with exactly + // the same predecessors BB had. + + // Copy over any phi, debug or lifetime instruction. + BB->getTerminator()->eraseFromParent(); + Succ->getInstList().splice(Succ->getFirstNonPHI(), BB->getInstList()); + } else { + while (PHINode *PN = dyn_cast<PHINode>(&BB->front())) { // We explicitly check for such uses in CanPropagatePredecessorsForPHIs. assert(PN->use_empty() && "There shouldn't be any uses here!"); PN->eraseFromParent(); @@ -642,7 +644,7 @@ bool llvm::EliminateDuplicatePHINodes(BasicBlock *BB) { bool Changed = false; // This implementation doesn't currently consider undef operands - // specially. Theroetically, two phis which are identical except for + // specially. Theoretically, two phis which are identical except for // one having an undef where the other doesn't could be collapsed. // Map from PHI hash values to PHI nodes. If multiple PHIs have |