1; RUN: opt -S -jump-threading -verify -o - %s | FileCheck %s
2@a = external global i16, align 1
3
4; CHECK-LABEL: f
5; CHECK: bb6:
6; CHECK: bb2:
7; CHECK: bb3:
8; CHECK-NOT: bb0:
9; CHECK-NOT: bb1:
10; CHECK-NOT: bb4:
11; CHECK-NOT: bb5:
12define void @f(i32 %p1) {
13bb0:
14  %0 = icmp eq i32 %p1, 0
15  br i1 undef, label %bb6, label %bb1
16
17bb1:
18  br label %bb2
19
20bb2:
21  %1 = phi i1 [ %0, %bb1 ], [ %2, %bb4 ]
22  %2 = and i1 %1, undef
23  br i1 %2, label %bb3, label %bb4
24
25bb3:
26  store i16 undef, i16* @a, align 1
27  br label %bb4
28
29bb4:
30  br i1 %0, label %bb2, label %bb5
31
32bb5:
33  unreachable
34
35bb6:
36  ret void
37}
38