| Philip Reames | 846e3e4 | 2015-10-29 03:11:49 +0000 | [diff] [blame] | 1 | ; RUN: opt %s -S -simplifycfg | FileCheck %s |
| 2 | ; Check for when one branch implies the value of a successors conditional and |
| 3 | ; it's not simply the same conditional repeated. |
| 4 | |
| 5 | define void @test(i32 %length.i, i32 %i) { |
| 6 | ; CHECK-LABEL: @test |
| 7 | %iplus1 = add nsw i32 %i, 1 |
| 8 | %var29 = icmp slt i32 %iplus1, %length.i |
| 9 | ; CHECK: br i1 %var29, label %in_bounds, label %out_of_bounds |
| 10 | br i1 %var29, label %next, label %out_of_bounds |
| 11 | |
| 12 | next: |
| 13 | ; CHECK-LABEL: in_bounds: |
| 14 | ; CHECK-NEXT: ret void |
| 15 | %var30 = icmp slt i32 %i, %length.i |
| 16 | br i1 %var30, label %in_bounds, label %out_of_bounds2 |
| 17 | |
| 18 | in_bounds: |
| 19 | ret void |
| 20 | |
| 21 | out_of_bounds: |
| 22 | call void @foo(i64 0) |
| 23 | unreachable |
| 24 | |
| 25 | out_of_bounds2: |
| 26 | call void @foo(i64 1) |
| 27 | unreachable |
| 28 | } |
| 29 | |
| 30 | ; If the add is not nsw, it's not safe to use the fact about i+1 to imply the |
| 31 | ; i condition since it could have overflowed. |
| 32 | define void @test_neg(i32 %length.i, i32 %i) { |
| 33 | ; CHECK-LABEL: @test_neg |
| 34 | %iplus1 = add i32 %i, 1 |
| 35 | %var29 = icmp slt i32 %iplus1, %length.i |
| 36 | ; CHECK: br i1 %var29, label %next, label %out_of_bounds |
| 37 | br i1 %var29, label %next, label %out_of_bounds |
| 38 | |
| 39 | next: |
| 40 | %var30 = icmp slt i32 %i, %length.i |
| 41 | ; CHECK: br i1 %var30, label %in_bounds, label %out_of_bounds2 |
| 42 | br i1 %var30, label %in_bounds, label %out_of_bounds2 |
| 43 | |
| 44 | in_bounds: |
| 45 | ret void |
| 46 | |
| 47 | out_of_bounds: |
| 48 | call void @foo(i64 0) |
| 49 | unreachable |
| 50 | |
| 51 | out_of_bounds2: |
| 52 | call void @foo(i64 1) |
| 53 | unreachable |
| 54 | } |
| 55 | |
| 56 | |
| 57 | define void @test2(i32 %length.i, i32 %i) { |
| 58 | ; CHECK-LABEL: @test2 |
| 59 | %iplus100 = add nsw i32 %i, 100 |
| 60 | %var29 = icmp slt i32 %iplus100, %length.i |
| 61 | ; CHECK: br i1 %var29, label %in_bounds, label %out_of_bounds |
| 62 | br i1 %var29, label %next, label %out_of_bounds |
| 63 | |
| 64 | next: |
| 65 | %var30 = icmp slt i32 %i, %length.i |
| 66 | br i1 %var30, label %in_bounds, label %out_of_bounds2 |
| 67 | |
| 68 | in_bounds: |
| 69 | ret void |
| 70 | |
| 71 | out_of_bounds: |
| 72 | call void @foo(i64 0) |
| 73 | unreachable |
| 74 | |
| 75 | out_of_bounds2: |
| 76 | call void @foo(i64 1) |
| 77 | unreachable |
| 78 | } |
| 79 | |
| 80 | declare void @foo(i64) |
| 81 | |