diff --git a/llvm/test/Transforms/LowerTypeTests/distinct-index-width-crash.ll b/llvm/test/Transforms/LowerTypeTests/distinct-index-width-crash.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/Transforms/LowerTypeTests/distinct-index-width-crash.ll
@@ -0,0 +1,17 @@
+; RUN: not --crash opt -passes=lowertypetests %s -disable-output
+target datalayout = "e-p:64:64:64:32"
+
+@a = constant i32 1, !type !0
+@b = constant [2 x i32] [i32 2, i32 3], !type !1
+
+!0 = !{i32 0, !"typeid1"}
+!1 = !{i32 4, !"typeid1"}
+
+declare i1 @llvm.type.test(ptr %ptr, metadata %bitset) nounwind readnone
+
+; CHECK: @bar(
+define i1 @bar() {
+  ; CHECK: ret i1 true
+  %x = call i1 @llvm.type.test(ptr getelementptr ([2 x i32], ptr @b, i32 0, i32 1), metadata !"typeid1")
+  ret i1 %x
+}
diff --git a/llvm/test/Transforms/MergeFunc/different-index-width-gep-crash.ll b/llvm/test/Transforms/MergeFunc/different-index-width-gep-crash.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/Transforms/MergeFunc/different-index-width-gep-crash.ll
@@ -0,0 +1,13 @@
+; RUN: not --crash opt -disable-output -passes=mergefunc -S < %s
+
+target datalayout = "e-p:64:64-p2:128:128:128:32"
+
+define void @foo(ptr addrspace(2) %x) {
+    %tmp = getelementptr i32, ptr addrspace(2) %x, i32 1
+    ret void
+}
+
+define void @bar(ptr addrspace(2) %x) {
+    %tmp = getelementptr i32, ptr addrspace(2) %x, i32 1
+    ret void
+}
diff --git a/llvm/test/Transforms/MergeICmps/X86/distinct-index-width-crash.ll b/llvm/test/Transforms/MergeICmps/X86/distinct-index-width-crash.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/Transforms/MergeICmps/X86/distinct-index-width-crash.ll
@@ -0,0 +1,32 @@
+; RUN: not --crash opt < %s -passes=mergeicmps -verify-dom-info -disable-output
+
+target triple = "x86_64"
+
+; This is very much not an x86 ABI, in current use, but we're testing
+; that we've fixed a bug where accumulateConstantOffset() was called incorrectly.
+target datalayout = "e-p:64:64:64:32"
+
+; Define a cunstom data layout that has index width < pointer width
+; and make sure that doesn't mreak anything
+define void @fat_ptrs(ptr dereferenceable(16) %a, ptr dereferenceable(16) %b) {
+bb0:
+  %ptr_a1 = getelementptr inbounds [2 x i64], ptr %a, i64 0, i64 1
+  %ptr_b1 = getelementptr inbounds [2 x i64], ptr %b, i64 0, i64 1
+  br label %bb1
+
+bb1:                                              ; preds = %bb0
+  %a0 = load i64, ptr %a
+  %b0 = load i64, ptr %b
+  %cond0 = icmp eq i64 %a0, %b0
+  br i1 %cond0, label %bb2, label %bb3
+
+bb2:                                              ; preds = %bb1
+  %a1 = load i64, ptr %ptr_a1
+  %b1 = load i64, ptr %ptr_b1
+  %cond1 = icmp eq i64 %a1, %b1
+  br label %bb3
+
+bb3:                                              ; preds = %bb2, %bb1
+  %necessary = phi i1 [ %cond1, %bb2 ], [ false, %bb1 ]
+  ret void
+}