diff --git a/llvm/include/llvm/Transforms/Utils/GuardUtils.h b/llvm/include/llvm/Transforms/Utils/GuardUtils.h
--- a/llvm/include/llvm/Transforms/Utils/GuardUtils.h
+++ b/llvm/include/llvm/Transforms/Utils/GuardUtils.h
@@ -17,6 +17,7 @@
 class BranchInst;
 class CallInst;
 class Function;
+class LoopInfo;
 class Value;
 
 /// Splits control flow at point of \p Guard, replacing it with explicit branch
@@ -32,12 +33,14 @@
 /// Given a branch we know is widenable (defined per Analysis/GuardUtils.h),
 /// widen it such that condition 'NewCond' is also known to hold on the taken
 /// path.  Branch remains widenable after transform.
-void widenWidenableBranch(BranchInst *WidenableBR, Value *NewCond);
+void widenWidenableBranch(BranchInst *WidenableBR, Value *NewCond,
+                          const LoopInfo &LI);
 
 /// Given a branch we know is widenable (defined per Analysis/GuardUtils.h),
 /// *set* it's condition such that (only) 'Cond' is known to hold on the taken
 /// path and that the branch remains widenable after transform.
-void setWidenableBranchCond(BranchInst *WidenableBR, Value *Cond);
+void setWidenableBranchCond(BranchInst *WidenableBR, Value *Cond,
+                            const LoopInfo &LI);
 
 } // llvm
 
diff --git a/llvm/lib/Transforms/Scalar/GuardWidening.cpp b/llvm/lib/Transforms/Scalar/GuardWidening.cpp
--- a/llvm/lib/Transforms/Scalar/GuardWidening.cpp
+++ b/llvm/lib/Transforms/Scalar/GuardWidening.cpp
@@ -289,7 +289,7 @@
     widenCondCommon(getCondition(ToWiden), NewCondition, InsertPt, Result,
                     InvertCondition);
     if (isGuardAsWidenableBranch(ToWiden)) {
-      setWidenableBranchCond(cast<BranchInst>(ToWiden), Result);
+      setWidenableBranchCond(cast<BranchInst>(ToWiden), Result, LI);
       return;
     }
     setCondition(ToWiden, Result);
diff --git a/llvm/lib/Transforms/Scalar/LoopPredication.cpp b/llvm/lib/Transforms/Scalar/LoopPredication.cpp
--- a/llvm/lib/Transforms/Scalar/LoopPredication.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopPredication.cpp
@@ -1248,7 +1248,7 @@
     // context.
     NewCond = B.CreateFreeze(NewCond);
 
-    widenWidenableBranch(WidenableBR, NewCond);
+    widenWidenableBranch(WidenableBR, NewCond, *LI);
 
     Value *OldCond = BI->getCondition();
     BI->setCondition(ConstantInt::get(OldCond->getType(), !ExitIfTrue));
diff --git a/llvm/lib/Transforms/Utils/GuardUtils.cpp b/llvm/lib/Transforms/Utils/GuardUtils.cpp
--- a/llvm/lib/Transforms/Utils/GuardUtils.cpp
+++ b/llvm/lib/Transforms/Utils/GuardUtils.cpp
@@ -11,6 +11,7 @@
 
 #include "llvm/Transforms/Utils/GuardUtils.h"
 #include "llvm/Analysis/GuardUtils.h"
+#include "llvm/Analysis/LoopInfo.h"
 #include "llvm/IR/Function.h"
 #include "llvm/IR/IRBuilder.h"
 #include "llvm/IR/Instructions.h"
@@ -78,8 +79,8 @@
   }
 }
 
-
-void llvm::widenWidenableBranch(BranchInst *WidenableBR, Value *NewCond) {
+void llvm::widenWidenableBranch(BranchInst *WidenableBR, Value *NewCond,
+                                const LoopInfo &LI) {
   assert(isWidenableBranch(WidenableBR) && "precondition");
 
   // The tempting trivially option is to produce something like this:
@@ -90,6 +91,13 @@
   Use *C, *WC;
   BasicBlock *IfTrueBB, *IfFalseBB;
   parseWidenableBranch(WidenableBR, C, WC, IfTrueBB, IfFalseBB);
+#ifndef NDEBUG
+  bool IsLoopInvariantWidenableBR = false;
+  auto *L = LI.getLoopFor(WidenableBR->getParent());
+  if (L)
+    IsLoopInvariantWidenableBR =
+        L->isLoopInvariant(WidenableBR->getCondition());
+#endif
   if (!C) {
     // br (wc()), ... form
     IRBuilder<> B(WidenableBR);
@@ -102,15 +110,33 @@
     // Condition is only guaranteed to dominate branch
     WCAnd->moveBefore(WidenableBR);    
   }
+#ifndef NDEBUG
+  if (IsLoopInvariantWidenableBR) {
+    auto *L = LI.getLoopFor(WidenableBR->getParent());
+    // NB! This can also be loop-varying if we missed hoisting the IR out, which
+    // was infact loop-invariant. This would imply a pass-ordering issue and the
+    // assert should be dealt with as such.
+    assert(L->isLoopInvariant(WidenableBR->getCondition()) &&
+           "Loop invariant widenable condition made loop variant!");
+  }
+#endif
   assert(isWidenableBranch(WidenableBR) && "preserve widenabiliy");
 }
 
-void llvm::setWidenableBranchCond(BranchInst *WidenableBR, Value *NewCond) {
+void llvm::setWidenableBranchCond(BranchInst *WidenableBR, Value *NewCond,
+                                  const LoopInfo &LI) {
   assert(isWidenableBranch(WidenableBR) && "precondition");
 
   Use *C, *WC;
   BasicBlock *IfTrueBB, *IfFalseBB;
   parseWidenableBranch(WidenableBR, C, WC, IfTrueBB, IfFalseBB);
+#ifndef NDEBUG
+  bool IsLoopInvariantWidenableBR = false;
+  auto *L = LI.getLoopFor(WidenableBR->getParent());
+  if (L)
+    IsLoopInvariantWidenableBR =
+        L->isLoopInvariant(WidenableBR->getCondition());
+#endif
   if (!C) {
     // br (wc()), ... form
     IRBuilder<> B(WidenableBR);
@@ -122,5 +148,15 @@
     WCAnd->moveBefore(WidenableBR);
     C->set(NewCond);
   }
+#ifndef NDEBUG
+  if (IsLoopInvariantWidenableBR) {
+    auto *L = LI.getLoopFor(WidenableBR->getParent());
+    // NB! This can also be loop-varying if we missed hoisting the IR out, which
+    // was infact loop-invariant. This would imply a pass-ordering issue and the
+    // assert should be dealt with as such.
+    assert(L->isLoopInvariant(WidenableBR->getCondition()) &&
+           "Loop invariant widenable condition made loop variant!");
+  }
+#endif
   assert(isWidenableBranch(WidenableBR) && "preserve widenabiliy");
 }