1 ; RUN: opt < %s -simplifycfg -S | FileCheck %s 2 3 ; CHECK-NOT: switch 4 5 ; Test normal folding 6 define i32 @test1() { 7 switch i32 5, label %Default [ 8 i32 0, label %Foo 9 i32 1, label %Bar 10 i32 2, label %Baz 11 i32 5, label %TheDest 12 ] 13 Default: ; preds = %0 14 ret i32 -1 15 Foo: ; preds = %0 16 ret i32 -2 17 Bar: ; preds = %0 18 ret i32 -3 19 Baz: ; preds = %0 20 ret i32 -4 21 TheDest: ; preds = %0 22 ret i32 1234 23 } 24 25 ; Test folding to default dest 26 define i32 @test2() { 27 switch i32 3, label %Default [ 28 i32 0, label %Foo 29 i32 1, label %Bar 30 i32 2, label %Baz 31 i32 5, label %TheDest 32 ] 33 Default: ; preds = %0 34 ret i32 1234 35 Foo: ; preds = %0 36 ret i32 -2 37 Bar: ; preds = %0 38 ret i32 -5 39 Baz: ; preds = %0 40 ret i32 -6 41 TheDest: ; preds = %0 42 ret i32 -8 43 } 44 45 ; Test folding all to same dest 46 define i32 @test3(i1 %C) { 47 br i1 %C, label %Start, label %TheDest 48 Start: ; preds = %0 49 switch i32 3, label %TheDest [ 50 i32 0, label %TheDest 51 i32 1, label %TheDest 52 i32 2, label %TheDest 53 i32 5, label %TheDest 54 ] 55 TheDest: ; preds = %Start, %Start, %Start, %Start, %Start, %0 56 ret i32 1234 57 } 58 59 ; Test folding switch -> branch 60 define i32 @test4(i32 %C) { 61 switch i32 %C, label %L1 [ 62 i32 0, label %L2 63 ] 64 L1: ; preds = %0 65 ret i32 0 66 L2: ; preds = %0 67 ret i32 1 68 } 69 70 ; Can fold into a cond branch! 71 define i32 @test5(i32 %C) { 72 switch i32 %C, label %L1 [ 73 i32 0, label %L2 74 i32 123, label %L1 75 ] 76 L1: ; preds = %0, %0 77 ret i32 0 78 L2: ; preds = %0 79 ret i32 1 80 } 81 82
