From 43fdc54303760237cf61198a6ba1da14524f2f0e Mon Sep 17 00:00:00 2001
From: Sanjoy Das <sanjoy@playingwithpointers.com>
Date: Sun, 14 Aug 2016 01:04:31 +0000
Subject: [PATCH] [IRCE] Add better DEBUG diagnostic; NFC

NFC meaning IRCE should not _do_ anything different, but
-debug-only=irce will be a little friendlier.

llvm-svn: 278616
---
 llvm/lib/Transforms/Scalar/InductiveRangeCheckElimination.cpp | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/llvm/lib/Transforms/Scalar/InductiveRangeCheckElimination.cpp b/llvm/lib/Transforms/Scalar/InductiveRangeCheckElimination.cpp
index 3f9432e4..b3d8aa6 100644
--- a/llvm/lib/Transforms/Scalar/InductiveRangeCheckElimination.cpp
+++ b/llvm/lib/Transforms/Scalar/InductiveRangeCheckElimination.cpp
@@ -622,8 +622,10 @@ static bool CanBeSMin(ScalarEvolution &SE, const SCEV *S) {
 Optional<LoopStructure>
 LoopStructure::parseLoopStructure(ScalarEvolution &SE, BranchProbabilityInfo &BPI,
                                   Loop &L, const char *&FailureReason) {
-  if (!L.isLoopSimplifyForm())
+  if (!L.isLoopSimplifyForm()) {
+    FailureReason = "loop not in LoopSimplify form";
     return None;
+  }
 
   BasicBlock *Latch = L.getLoopLatch();
   assert(Latch && "Simplified loops only have one latch!");
-- 
2.7.4