From 8eaa5b9abab3a358353c3d925b1dd0b3a6ee4b42 Mon Sep 17 00:00:00 2001 From: Philip Reames Date: Thu, 17 Oct 2019 23:49:46 +0000 Subject: [PATCH] [IndVars] Factor out some common code into a utility function As requested in review of D69009 llvm-svn: 375191 --- llvm/lib/Transforms/Scalar/IndVarSimplify.cpp | 29 +++++++++---------- 1 file changed, 13 insertions(+), 16 deletions(-) diff --git a/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp b/llvm/lib/Transforms/Scalar/IndVarSimplify.cpp index a5edb8052f6f..6299deca08c9 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(MaxExitCount)) return false; + auto FoldExit = [&](BasicBlock *ExitingBB, bool IsTaken) { + BranchInst *BI = cast(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) { - BranchInst *BI = cast(ExitingBB->getTerminator()); - const SCEV *ExitCount = SE->getExitCount(L, ExitingBB); assert(!isa(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; }