diff options
| -rw-r--r-- | llvm/lib/Transforms/Vectorize/LoopVectorize.cpp | 4 | ||||
| -rw-r--r-- | llvm/test/Transforms/LoopVectorize/legal_preheader_check.ll | 27 |
2 files changed, 29 insertions, 2 deletions
diff --git a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp index fbcdc0df0f1..52f32cda260 100644 --- a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp +++ b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp @@ -5049,13 +5049,13 @@ bool LoopVectorizationLegality::canVectorize() { bool Result = true; bool DoExtraAnalysis = ORE->allowExtraAnalysis(DEBUG_TYPE); - if (DoExtraAnalysis) // We must have a loop in canonical form. Loops with indirectbr in them cannot // be canonicalized. if (!TheLoop->getLoopPreheader()) { + DEBUG(dbgs() << "LV: Loop doesn't have a legal pre-header.\n"); ORE->emit(createMissedAnalysis("CFGNotUnderstood") << "loop control flow is not understood by vectorizer"); - if (DoExtraAnalysis) + if (DoExtraAnalysis) Result = false; else return false; diff --git a/llvm/test/Transforms/LoopVectorize/legal_preheader_check.ll b/llvm/test/Transforms/LoopVectorize/legal_preheader_check.ll new file mode 100644 index 00000000000..32aa796394d --- /dev/null +++ b/llvm/test/Transforms/LoopVectorize/legal_preheader_check.ll @@ -0,0 +1,27 @@ +; RUN: opt < %s -loop-vectorize -debug -S -o /dev/null 2>&1 | FileCheck %s +; REQUIRES: asserts + +; D40973 +; Make sure LV legal bails out when the loop doesn't have a legal pre-header. + +; CHECK: LV: Loop doesn't have a legal pre-header. + +define void @inc(i32 %n, i8* %P) { + %1 = icmp sgt i32 %n, 0 + br i1 %1, label %BB1, label %BB2 + +BB1: + indirectbr i8* %P, [label %.lr.ph] + +BB2: + br label %.lr.ph + +.lr.ph: + %indvars.iv = phi i32 [ %indvars.iv.next, %.lr.ph ], [ 0, %BB1 ], [ 0, %BB2 ] + %indvars.iv.next = add i32 %indvars.iv, 1 + %exitcond = icmp eq i32 %indvars.iv.next, %n + br i1 %exitcond, label %._crit_edge, label %.lr.ph + +._crit_edge: + ret void +} |
