diff options
| -rw-r--r-- | lib/Analysis/ScalarEvolution.cpp | 18 | ||||
| -rw-r--r-- | test/Transforms/LoopUnroll/pr11361.ll | 42 |
2 files changed, 60 insertions, 0 deletions
diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp index b940d93..ac00259 100644 --- a/lib/Analysis/ScalarEvolution.cpp +++ b/lib/Analysis/ScalarEvolution.cpp @@ -4853,10 +4853,18 @@ ScalarEvolution::getConstantEvolutionLoopExitValue(PHINode *PN, // Also evaluate the other PHI nodes. However, we don't get to stop if we // cease to be able to evaluate one of them or if they stop evolving, // because that doesn't necessarily prevent us from computing PN. + SmallVector<std::pair<PHINode *, Constant *>, 8> PHIsToCompute; for (DenseMap<Instruction *, Constant *>::const_iterator I = CurrentIterVals.begin(), E = CurrentIterVals.end(); I != E; ++I){ PHINode *PHI = dyn_cast<PHINode>(I->first); if (!PHI || PHI == PN || PHI->getParent() != Header) continue; + PHIsToCompute.push_back(std::make_pair(PHI, I->second)); + } + // We use two distinct loops because EvaluateExpression may invalidate any + // iterators into CurrentIterVals. + for (SmallVectorImpl<std::pair<PHINode *, Constant*> >::const_iterator + I = PHIsToCompute.begin(), E = PHIsToCompute.end(); I != E; ++I) { + PHINode *PHI = I->first; Constant *&NextPHI = NextIterVals[PHI]; if (!NextPHI) { // Not already computed. Value *BEValue = PHI->getIncomingValue(SecondIsBackedge); @@ -4928,10 +4936,20 @@ const SCEV *ScalarEvolution::ComputeExitCountExhaustively(const Loop *L, // Update all the PHI nodes for the next iteration. DenseMap<Instruction *, Constant *> NextIterVals; + + // Create a list of which PHIs we need to compute. We want to do this before + // calling EvaluateExpression on them because that may invalidate iterators + // into CurrentIterVals. + SmallVector<PHINode *, 8> PHIsToCompute; for (DenseMap<Instruction *, Constant *>::const_iterator I = CurrentIterVals.begin(), E = CurrentIterVals.end(); I != E; ++I){ PHINode *PHI = dyn_cast<PHINode>(I->first); if (!PHI || PHI->getParent() != Header) continue; + PHIsToCompute.push_back(PHI); + } + for (SmallVectorImpl<PHINode *>::const_iterator I = PHIsToCompute.begin(), + E = PHIsToCompute.end(); I != E; ++I) { + PHINode *PHI = *I; Constant *&NextPHI = NextIterVals[PHI]; if (NextPHI) continue; // Already computed! diff --git a/test/Transforms/LoopUnroll/pr11361.ll b/test/Transforms/LoopUnroll/pr11361.ll new file mode 100644 index 0000000..7ce7f5f --- /dev/null +++ b/test/Transforms/LoopUnroll/pr11361.ll @@ -0,0 +1,42 @@ +; RUN: opt -loop-unroll -disable-output +; PR11361 + +; This tests for an iterator invalidation issue. + +target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +define void @func_1() nounwind uwtable { +entry: + br label %for.cond8.preheader + +for.cond8.preheader: ; preds = %for.inc15, %entry + %l_1264.04 = phi i32 [ 0, %entry ], [ %add.i, %for.inc15 ] + %l_1330.0.03 = phi i80 [ undef, %entry ], [ %ins.lcssa, %for.inc15 ] + br label %for.body9 + +for.body9: ; preds = %for.body9, %for.cond8.preheader + %l_1330.0.12 = phi i80 [ %l_1330.0.03, %for.cond8.preheader ], [ %ins, %for.body9 ] + %storemerge1 = phi i32 [ 7, %for.cond8.preheader ], [ %sub, %for.body9 ] + %tmp = lshr i80 %l_1330.0.12, 8 + %tmp1 = trunc i80 %tmp to i8 + %inc12 = add i8 %tmp1, 1 + %tmp2 = zext i8 %inc12 to i80 + %tmp3 = shl nuw nsw i80 %tmp2, 8 + %mask = and i80 %l_1330.0.12, -65281 + %ins = or i80 %tmp3, %mask + %sub = add nsw i32 %storemerge1, -1 + %tobool = icmp eq i32 %sub, 0 + br i1 %tobool, label %for.inc15, label %for.body9 + +for.inc15: ; preds = %for.body9 + %ins.lcssa = phi i80 [ %ins, %for.body9 ] + %sext = shl i32 %l_1264.04, 24 + %conv.i = ashr exact i32 %sext, 24 + %add.i = add nsw i32 %conv.i, 1 + %cmp = icmp slt i32 %add.i, 3 + br i1 %cmp, label %for.cond8.preheader, label %for.end16 + +for.end16: ; preds = %for.inc15 + ret void +} |