[LoopInfo] Add verification by recomputation.

Summary:
Current implementation of LI verifier isn't ideal and fails to detect
some cases when LI is incorrect. For instance, it checks that all
recorded loops are in a correct form, but it has no way to check if
there are no more other (unrecorded in LI) loops in the function. This
patch adds a way to detect such bugs.

Reviewers: chandlerc, sanjoy, hfinkel

Subscribers: llvm-commits, silvas, mzolotukhin

Differential Revision: https://reviews.llvm.org/D23437

llvm-svn: 280280

1 files changed, 1 insertions, 1 deletions

diff --git a/llvm/lib/Transforms/Scalar/LoopDistribute.cpp b/llvm/lib/Transforms/Scalar/LoopDistribute.cpp
index 74cfdbf..ad973cf 100644
--- a/llvm/lib/Transforms/Scalar/LoopDistribute.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopDistribute.cpp
@@ -742,7 +742,7 @@ public:
     DEBUG(Partitions.printBlocks());
 
     if (LDistVerify) {
-      LI->verify();
+      LI->verify(*DT);
       DT->verifyDomTree();
     }