Index: llvm/lib/Analysis/LoopInfo.cpp
===================================================================
--- llvm/lib/Analysis/LoopInfo.cpp
+++ llvm/lib/Analysis/LoopInfo.cpp
@@ -364,17 +364,14 @@
 }
 
 BranchInst *Loop::getLoopGuardBranch() const {
-  if (!isLoopSimplifyForm())
-    return nullptr;
-
   BasicBlock *Preheader = getLoopPreheader();
-  assert(Preheader && getLoopLatch() &&
-         "Expecting a loop with valid preheader and latch");
-
+  if (!Preheader)
+    return nullptr;
+  if (!getLoopLatch())
+    return nullptr;
   // Loop should be in rotate form.
   if (!isRotatedForm())
     return nullptr;
-
   // Disallow loops with more than one unique exit block, as we do not verify
   // that GuardOtherSucc post dominates all exit blocks.
   BasicBlock *ExitFromLatch = getUniqueExitBlock();
@@ -384,7 +381,6 @@
   BasicBlock *GuardBB = Preheader->getUniquePredecessor();
   if (!GuardBB)
     return nullptr;
-
   assert(GuardBB->getTerminator() && "Expecting valid guard terminator");
 
   BranchInst *GuardBI = dyn_cast<BranchInst>(GuardBB->getTerminator());
@@ -394,6 +390,12 @@
   BasicBlock *GuardOtherSucc = (GuardBI->getSuccessor(0) == Preheader)
                                    ? GuardBI->getSuccessor(1)
                                    : GuardBI->getSuccessor(0);
+  if (!hasDedicatedExits()) {
+    if (ExitFromLatch->hasNPredecessors(2) && ExitFromLatch == GuardOtherSucc) {
+      return GuardBI;
+    }
+    return nullptr;
+  }
 
   // Check if ExitFromLatch (or any BasicBlock which is an empty unique
   // successor of ExitFromLatch) is equal to GuardOtherSucc. If
Index: llvm/unittests/Analysis/LoopInfoTest.cpp
===================================================================
--- llvm/unittests/Analysis/LoopInfoTest.cpp
+++ llvm/unittests/Analysis/LoopInfoTest.cpp
@@ -1547,3 +1547,43 @@
     EXPECT_EQ(L->getLoopGuardBranch(), nullptr);
   });
 }
+
+TEST(LoopInfoTest, NoDedicatedExitsButTheSameBBWithGuard) {
+  const char *ModuleStr =
+      "target datalayout = \"e-m:o-i64:64-f80:128-n8:16:32:64-S128\"\n"
+      "define void @foo(i32* %B, i64 signext %nx, i1 %cond) {\n"
+      "entry:\n"
+      "  %cmp.guard = icmp slt i64 0, %nx\n"
+      "  br i1 %cmp.guard, label %for.i.preheader, label %for.i.exit\n"
+      "for.i.preheader:\n"
+      "  br label %for.i\n"
+      "for.i:\n"
+      "  %i = phi i64 [ 0, %for.i.preheader ], [ %inc13, %for.i ]\n"
+      "  %Bi = getelementptr inbounds i32, i32* %B, i64 %i\n"
+      "  store i32 0, i32* %Bi, align 4\n"
+      "  %inc13 = add nsw i64 %i, 1\n"
+      "  %cmp = icmp slt i64 %inc13, %nx\n"
+      "  br i1 %cmp, label %for.i, label %for.i.exit\n"
+      "for.i.exit:\n"
+      "  ret void\n"
+      "}\n";
+
+  // Parse the module.
+  LLVMContext Context;
+  std::unique_ptr<Module> M = makeLLVMModule(Context, ModuleStr);
+
+  runWithLoopInfo(*M, "foo", [&](Function &F, LoopInfo &LI) {
+    Function::iterator FI = F.begin();
+    assert(FI->getName() == "entry");
+
+    FI = ++FI;
+    BasicBlock *Header = &*(++FI);
+    assert(Header->getName() == "for.i");
+
+    Loop *L = LI.getLoopFor(Header);
+    EXPECT_NE(L, nullptr);
+
+    EXPECT_EQ(L->isGuarded(), true);
+    EXPECT_NE(L->getLoopGuardBranch(), nullptr);
+  });
+}