diff options
| -rw-r--r-- | llvm/lib/Transforms/Scalar/JumpThreading.cpp | 15 |
1 files changed, 11 insertions, 4 deletions
diff --git a/llvm/lib/Transforms/Scalar/JumpThreading.cpp b/llvm/lib/Transforms/Scalar/JumpThreading.cpp index fb784ff6532..566ebedc917 100644 --- a/llvm/lib/Transforms/Scalar/JumpThreading.cpp +++ b/llvm/lib/Transforms/Scalar/JumpThreading.cpp @@ -808,7 +808,12 @@ bool JumpThreadingPass::ProcessBlock(BasicBlock *BB) { // TODO: This should be extended to handle switches as well. BranchInst *CondBr = dyn_cast<BranchInst>(BB->getTerminator()); Constant *CondConst = dyn_cast<Constant>(CondCmp->getOperand(1)); - if (CondBr && CondConst && CondBr->isConditional()) { + if (CondBr && CondConst) { + // We should have returned as soon as we turn a conditional branch to + // unconditional. Because its no longer interesting as far as jump + // threading is concerned. + assert(CondBr->isConditional() && "Threading on unconditional terminator"); + LazyValueInfo::Tristate Ret = LVI->getPredicateAt(CondCmp->getPredicate(), CondCmp->getOperand(0), CondConst, CondBr); @@ -831,10 +836,12 @@ bool JumpThreadingPass::ProcessBlock(BasicBlock *BB) { } return true; } - } - if (CondBr && CondConst && TryToUnfoldSelect(CondCmp, BB)) - return true; + // We did not manage to simplify this branch, try to see whether + // CondCmp depends on a known phi-select pattern. + if (TryToUnfoldSelect(CondCmp, BB)) + return true; + } } // Check for some cases that are worth simplifying. Right now we want to look |
