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| ; 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()
|