[LV] Fix miscompiles by adding non-header PHI nodes to AllowedExit

Summary:
Fold-tail currently supports reduction last-vector-value live-out's,
but has yet to support last-scalar-value live-outs, including
non-header phi's. As it relies on AllowedExit in order to detect
them and bail out we need to add the non-header PHI nodes to
AllowedExit, otherwise we end up with miscompiles.

Solves https://bugs.llvm.org/show_bug.cgi?id=43166

Reviewers: fhahn, Ayal

Reviewed By: fhahn, Ayal

Subscribers: anna, hiraditya, rkruppe, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D67074

llvm-svn: 370721

1 files changed, 2 insertions, 2 deletions

diff --git a/llvm/include/llvm/Transforms/Vectorize/LoopVectorizationLegality.h b/llvm/include/llvm/Transforms/Vectorize/LoopVectorizationLegality.h
index 62ecd6d6aa3..d1e7acc877b 100644
--- a/llvm/include/llvm/Transforms/Vectorize/LoopVectorizationLegality.h
+++ b/llvm/include/llvm/Transforms/Vectorize/LoopVectorizationLegality.h
@@ -444,8 +444,8 @@ private:
   /// Holds the widest induction type encountered.
   Type *WidestIndTy = nullptr;
 
-  /// Allowed outside users. This holds the induction and reduction
-  /// vars which can be accessed from outside the loop.
+  /// Allowed outside users. This holds the variables that can be accessed from
+  /// outside the loop.
   SmallPtrSet<Value *, 4> AllowedExit;
 
   /// Can we assume the absence of NaNs.