| ; RUN: opt -gvn -S -o - %s | FileCheck %s | 
 |  | 
 | ; If a branch has two identical successors, we cannot declare either dead. | 
 |  | 
 | define void @widget(i1 %p) { | 
 | entry: | 
 |   br label %bb2 | 
 |  | 
 | bb2: | 
 |   %t1 = phi i64 [ 0, %entry ], [ %t5, %bb7 ] | 
 |   %t2 = add i64 %t1, 1 | 
 |   %t3 = icmp ult i64 0, %t2 | 
 |   br i1 %t3, label %bb3, label %bb4 | 
 |  | 
 | bb3: | 
 |   %t4 = call i64 @f() | 
 |   br label %bb4 | 
 |  | 
 | bb4: | 
 |   ; CHECK-NOT: phi {{.*}} undef | 
 |   %foo = phi i64 [ %t4, %bb3 ], [ 0, %bb2 ] | 
 |   br i1 %p, label %bb5, label %bb6 | 
 |  | 
 | bb5: | 
 |   br i1 true, label %bb7, label %bb7 | 
 |  | 
 | bb6: | 
 |   br i1 true, label %bb7, label %bb7 | 
 |  | 
 | bb7: | 
 |   %t5 = add i64 %t1, 1 | 
 |   br i1 %p, label %bb2, label %bb8 | 
 |  | 
 | bb8: | 
 |   ret void | 
 | } | 
 |  | 
 | declare i64 @f() |