| Peter Collingbourne | 2a3443c | 2015-06-25 18:32:02 +0000 | [diff] [blame^] | 1 | ; RUN: opt -gvn -S -o - %s | FileCheck %s |
| 2 | |
| 3 | ; If a branch has two identical successors, we cannot declare either dead. |
| 4 | |
| 5 | define void @widget(i1 %p) { |
| 6 | entry: |
| 7 | br label %bb2 |
| 8 | |
| 9 | bb2: |
| 10 | %t1 = phi i64 [ 0, %entry ], [ %t5, %bb7 ] |
| 11 | %t2 = add i64 %t1, 1 |
| 12 | %t3 = icmp ult i64 0, %t2 |
| 13 | br i1 %t3, label %bb3, label %bb4 |
| 14 | |
| 15 | bb3: |
| 16 | %t4 = call i64 @f() |
| 17 | br label %bb4 |
| 18 | |
| 19 | bb4: |
| 20 | ; CHECK-NOT: phi {{.*}} undef |
| 21 | %foo = phi i64 [ %t4, %bb3 ], [ 0, %bb2 ] |
| 22 | br i1 %p, label %bb5, label %bb6 |
| 23 | |
| 24 | bb5: |
| 25 | br i1 true, label %bb7, label %bb7 |
| 26 | |
| 27 | bb6: |
| 28 | br i1 true, label %bb7, label %bb7 |
| 29 | |
| 30 | bb7: |
| 31 | %t5 = add i64 %t1, 1 |
| 32 | br i1 %p, label %bb2, label %bb8 |
| 33 | |
| 34 | bb8: |
| 35 | ret void |
| 36 | } |
| 37 | |
| 38 | declare i64 @f() |