| Eric Christopher | cee313d | 2019-04-17 04:52:47 +0000 | [diff] [blame] | 1 | ; RUN: opt < %s -simplifycfg -S | FileCheck %s |
| 2 | |
| 3 | ; Test that we can thread a simple known condition through switch statements. |
| 4 | |
| 5 | declare void @foo1() |
| 6 | |
| 7 | declare void @foo2() |
| 8 | |
| 9 | declare void @DEAD() |
| 10 | |
| 11 | define void @test1(i32 %V) { |
| 12 | switch i32 %V, label %A [ |
| 13 | i32 4, label %T |
| 14 | i32 17, label %Done |
| 15 | i32 1234, label %A |
| 16 | ] |
| 17 | ;; V == 4 if we get here. |
| 18 | T: ; preds = %0 |
| 19 | call void @foo1( ) |
| 20 | ;; This switch is always statically determined. |
| 21 | switch i32 %V, label %A2 [ |
| 22 | i32 4, label %B |
| 23 | i32 17, label %C |
| 24 | i32 42, label %C |
| 25 | ] |
| 26 | A2: ; preds = %T |
| 27 | call void @DEAD( ) |
| 28 | call void @DEAD( ) |
| 29 | ;; always true |
| 30 | %cond2 = icmp eq i32 %V, 4 ; <i1> [#uses=1] |
| 31 | br i1 %cond2, label %Done, label %C |
| 32 | A: ; preds = %0, %0 |
| 33 | call void @foo1( ) |
| 34 | ;; always true |
| 35 | %cond = icmp ne i32 %V, 4 ; <i1> [#uses=1] |
| 36 | br i1 %cond, label %Done, label %C |
| 37 | Done: ; preds = %B, %A, %A2, %0 |
| 38 | ret void |
| 39 | B: ; preds = %T |
| 40 | call void @foo2( ) |
| 41 | ;; always true |
| 42 | %cond3 = icmp eq i32 %V, 4 ; <i1> [#uses=1] |
| 43 | br i1 %cond3, label %Done, label %C |
| 44 | C: ; preds = %B, %A, %A2, %T, %T |
| 45 | call void @DEAD( ) |
| 46 | ret void |
| 47 | |
| 48 | ; CHECK-LABEL: @test1( |
| 49 | ; CHECK-NEXT: switch i32 %V, label %A [ |
| 50 | ; CHECK-NEXT: i32 4, label %T |
| 51 | ; CHECK-NEXT: i32 17, label %Done |
| 52 | ; CHECK-NEXT: ] |
| 53 | ; CHECK: T: |
| 54 | ; CHECK-NEXT: call void @foo1() |
| 55 | ; CHECK-NEXT: call void @foo2() |
| 56 | ; CHECK-NEXT: br label %Done |
| 57 | ; CHECK: A: |
| 58 | ; CHECK-NEXT: call void @foo1() |
| 59 | ; CHECK-NEXT: br label %Done |
| 60 | ; CHECK: Done: |
| 61 | ; CHECK-NEXT: ret void |
| 62 | } |
| 63 | |
| 64 | define void @test2(i32 %V) { |
| 65 | switch i32 %V, label %A [ |
| 66 | i32 4, label %T |
| 67 | i32 17, label %D |
| 68 | i32 1234, label %E |
| 69 | ] |
| 70 | ;; V != 4, 17, 1234 here. |
| 71 | A: ; preds = %0 |
| 72 | call void @foo1( ) |
| 73 | ;; This switch is always statically determined. |
| 74 | switch i32 %V, label %E [ |
| 75 | i32 4, label %C |
| 76 | i32 17, label %C |
| 77 | i32 42, label %D |
| 78 | ] |
| 79 | ;; unreacahble. |
| 80 | C: ; preds = %A, %A |
| 81 | call void @DEAD( ) |
| 82 | ret void |
| 83 | T: ; preds = %0 |
| 84 | call void @foo1( ) |
| 85 | call void @foo1( ) |
| 86 | ret void |
| 87 | D: ; preds = %A, %0 |
| 88 | call void @foo1( ) |
| 89 | ret void |
| 90 | E: ; preds = %A, %0 |
| 91 | ret void |
| 92 | |
| 93 | ; CHECK-LABEL: @test2( |
| 94 | ; CHECK-NEXT: switch i32 %V, label %A [ |
| 95 | ; CHECK-NEXT: i32 4, label %T |
| 96 | ; CHECK-NEXT: i32 17, label %D |
| 97 | ; CHECK-NEXT: i32 1234, label %E |
| 98 | ; CHECK-NEXT: ] |
| 99 | ; CHECK: A: |
| 100 | ; CHECK-NEXT: call void @foo1() |
| 101 | ; CHECK-NEXT: [[COND:%.*]] = icmp eq i32 %V, 42 |
| 102 | ; CHECK-NEXT: br i1 [[COND]], label %D, label %E |
| 103 | ; CHECK: T: |
| 104 | ; CHECK-NEXT: call void @foo1() |
| 105 | ; CHECK-NEXT: call void @foo1() |
| 106 | ; CHECK-NEXT: ret void |
| 107 | ; CHECK: D: |
| 108 | ; CHECK-NEXT: call void @foo1() |
| 109 | ; CHECK-NEXT: ret void |
| 110 | ; CHECK: E: |
| 111 | ; CHECK-NEXT: ret void |
| 112 | } |
| 113 | |