diff options
| -rw-r--r-- | llvm/lib/Transforms/Scalar/IndVarSimplify.cpp | 29 |
1 files changed, 13 insertions, 16 deletions
diff --git a/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp b/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp index a5edb8052f6..6299deca08c 100644 --- a/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp +++ b/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp @@ -2717,10 +2717,19 @@ bool IndVarSimplify::optimizeLoopExits(Loop *L, SCEVExpander &Rewriter) { if (isa<SCEVCouldNotCompute>(MaxExitCount)) return false; - bool Changed = false; - for (BasicBlock *ExitingBB : ExitingBlocks) { + auto FoldExit = [&](BasicBlock *ExitingBB, bool IsTaken) { BranchInst *BI = cast<BranchInst>(ExitingBB->getTerminator()); + bool ExitIfTrue = !L->contains(*succ_begin(ExitingBB)); + auto *OldCond = BI->getCondition(); + auto *NewCond = ConstantInt::get(OldCond->getType(), + IsTaken ? ExitIfTrue : !ExitIfTrue); + BI->setCondition(NewCond); + if (OldCond->use_empty()) + DeadInsts.push_back(OldCond); + }; + bool Changed = false; + for (BasicBlock *ExitingBB : ExitingBlocks) { const SCEV *ExitCount = SE->getExitCount(L, ExitingBB); assert(!isa<SCEVCouldNotCompute>(ExitCount) && "checked above"); @@ -2730,13 +2739,7 @@ bool IndVarSimplify::optimizeLoopExits(Loop *L, SCEVExpander &Rewriter) { // TODO: Given we know the backedge can't be taken, we should go ahead // and break it. Or at least, kill all the header phis and simplify. if (ExitCount->isZero()) { - bool ExitIfTrue = !L->contains(*succ_begin(ExitingBB)); - auto *OldCond = BI->getCondition(); - auto *NewCond = ExitIfTrue ? ConstantInt::getTrue(OldCond->getType()) : - ConstantInt::getFalse(OldCond->getType()); - BI->setCondition(NewCond); - if (OldCond->use_empty()) - DeadInsts.push_back(OldCond); + FoldExit(ExitingBB, true); Changed = true; continue; } @@ -2758,13 +2761,7 @@ bool IndVarSimplify::optimizeLoopExits(Loop *L, SCEVExpander &Rewriter) { // one? if (SE->isLoopEntryGuardedByCond(L, CmpInst::ICMP_ULT, MaxExitCount, ExitCount)) { - bool ExitIfTrue = !L->contains(*succ_begin(ExitingBB)); - auto *OldCond = BI->getCondition(); - auto *NewCond = ExitIfTrue ? ConstantInt::getFalse(OldCond->getType()) : - ConstantInt::getTrue(OldCond->getType()); - BI->setCondition(NewCond); - if (OldCond->use_empty()) - DeadInsts.push_back(OldCond); + FoldExit(ExitingBB, false); Changed = true; continue; } |
