diff --git a/llvm/test/Transforms/LoopStrengthReduce/pr42770.ll b/llvm/test/Transforms/LoopStrengthReduce/pr42770.ll
new file mode 100644
index 000000000000..afe6778f783c
--- /dev/null
+++ b/llvm/test/Transforms/LoopStrengthReduce/pr42770.ll
@@ -0,0 +1,34 @@
+; Check that it doesn't crash
+; REQUIRES: asserts
+; XFAIL: *
+; RUN: opt < %s -loop-reduce -S
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128-ni:1"
+
+define void @foo() {
+bb:
+  br label %bb4
+
+bb1:                                              ; preds = %bb13
+  %tmp = shl i64 %tmp14, 32
+  %tmp2 = add i64 %tmp, 1
+  %tmp3 = ashr i64 %tmp2, 32
+  ret void
+
+bb4:                                              ; preds = %bb13, %bb
+  %tmp5 = phi i64 [ 2, %bb ], [ %tmp14, %bb13 ]
+  %tmp6 = add i64 %tmp5, 4
+  %tmp7 = trunc i64 %tmp6 to i16
+  %tmp8 = urem i16 %tmp7, 3
+  %tmp9 = mul i16 %tmp8, 2
+  %tmp10 = icmp eq i16 %tmp9, 1
+  br i1 %tmp10, label %bb11, label %bb13
+
+bb11:                                             ; preds = %bb4
+  %tmp12 = udiv i16 1, %tmp7
+  unreachable
+
+bb13:                                             ; preds = %bb4
+  %tmp14 = add nuw nsw i64 %tmp5, 6
+  br i1 undef, label %bb1, label %bb4
+}