diff options
| -rw-r--r-- | lib/Transforms/Scalar/LoopIndexSplit.cpp | 32 | ||||
| -rw-r--r-- | test/Transforms/LoopIndexSplit/2009-03-30-undef.ll | 24 |
2 files changed, 48 insertions, 8 deletions
diff --git a/lib/Transforms/Scalar/LoopIndexSplit.cpp b/lib/Transforms/Scalar/LoopIndexSplit.cpp index 98e5cc15d6..a8cfaaf3b8 100644 --- a/lib/Transforms/Scalar/LoopIndexSplit.cpp +++ b/lib/Transforms/Scalar/LoopIndexSplit.cpp @@ -48,6 +48,7 @@ #include "llvm/Analysis/Dominators.h" #include "llvm/Transforms/Utils/BasicBlockUtils.h" #include "llvm/Transforms/Utils/Cloning.h" +#include "llvm/Transforms/Utils/Local.h" #include "llvm/Support/Compiler.h" #include "llvm/ADT/DepthFirstIterator.h" #include "llvm/ADT/Statistic.h" @@ -345,10 +346,25 @@ bool LoopIndexSplit::processOneIterationLoop() { if (!L->isLoopInvariant(SplitValue)) return false; Instruction *OPI = dyn_cast<Instruction>(OPV); - if (!OPI) return false; + if (!OPI) + return false; if (OPI->getParent() != Header || isUsedOutsideLoop(OPI, L)) return false; - + Value *StartValue = IVStartValue; + Value *ExitValue = IVExitValue;; + + if (OPV != IndVar) { + // If BR operand is IV based then use this operand to calculate + // effective conditions for loop body. + BinaryOperator *BOPV = dyn_cast<BinaryOperator>(OPV); + if (!BOPV) + return false; + if (BOPV->getOpcode() != Instruction::Add) + return false; + StartValue = BinaryOperator::CreateAdd(OPV, StartValue, "" , BR); + ExitValue = BinaryOperator::CreateAdd(OPV, ExitValue, "" , BR); + } + if (!cleanBlock(Header)) return false; @@ -399,13 +415,13 @@ bool LoopIndexSplit::processOneIterationLoop() { // and i32 c1, c2 Instruction *C1 = new ICmpInst(ExitCondition->isSignedPredicate() ? ICmpInst::ICMP_SGE : ICmpInst::ICMP_UGE, - SplitValue, IVStartValue, "lisplit", BR); + SplitValue, StartValue, "lisplit", BR); CmpInst::Predicate C2P = ExitCondition->getPredicate(); BranchInst *LatchBR = cast<BranchInst>(Latch->getTerminator()); if (LatchBR->getOperand(0) != Header) C2P = CmpInst::getInversePredicate(C2P); - Instruction *C2 = new ICmpInst(C2P, SplitValue, IVExitValue, "lisplit", BR); + Instruction *C2 = new ICmpInst(C2P, SplitValue, ExitValue, "lisplit", BR); Instruction *NSplitCond = BinaryOperator::CreateAnd(C1, C2, "lisplit", BR); SplitCondition->replaceAllUsesWith(NSplitCond); @@ -419,11 +435,11 @@ bool LoopIndexSplit::processOneIterationLoop() { if (Header != *SI) LatchSucc = *SI; } - LatchBR->setUnconditionalDest(LatchSucc); - // Remove IVIncrement - IVIncrement->replaceAllUsesWith(UndefValue::get(IVIncrement->getType())); - IVIncrement->eraseFromParent(); + // Clean up latch block. + Value *LatchBRCond = LatchBR->getCondition(); + LatchBR->setUnconditionalDest(LatchSucc); + RecursivelyDeleteTriviallyDeadInstructions(LatchBRCond); LPM->deleteLoopFromQueue(L); diff --git a/test/Transforms/LoopIndexSplit/2009-03-30-undef.ll b/test/Transforms/LoopIndexSplit/2009-03-30-undef.ll new file mode 100644 index 0000000000..b34cb51c33 --- /dev/null +++ b/test/Transforms/LoopIndexSplit/2009-03-30-undef.ll @@ -0,0 +1,24 @@ +; RUN: llvm-as < %s | opt -loop-index-split | llvm-dis | not grep undef +define i32 @main() { +entry: + br label %header + +header: + %r = phi i32 [ 0, %entry ], [ %r3, %skip ] + %i = phi i32 [ 0, %entry ], [ %i1, %skip ] + %i99 = add i32 %i, 99 + %cond = icmp eq i32 %i99, 3 + br i1 %cond, label %body, label %skip + +body: + br label %skip + +skip: + %r3 = phi i32 [ %r, %header ], [ 3, %body ] + %i1 = add i32 %i, 1 + %exitcond = icmp eq i32 %i1, 10 + br i1 %exitcond, label %exit, label %header + +exit: + ret i32 %r3 +} |