1; REQUIRES: asserts 2; RUN: opt -loop-unswitch -loop-unswitch-threshold 1000 -disable-output -stats -info-output-file - < %s | FileCheck --check-prefix=STATS %s 3; RUN: opt -S -loop-unswitch -loop-unswitch-threshold 1000 -verify-loop-info -verify-dom-info < %s | FileCheck %s 4 5; STATS: 3 loop-unswitch - Number of switches unswitched 6 7; CHECK: %1 = icmp eq i32 %c, 1 8; CHECK-NEXT: br i1 %1, label %.split.us, label %..split_crit_edge 9 10; CHECK: ..split_crit_edge: ; preds = %0 11; CHECK-NEXT: br label %.split 12 13; CHECK: .split.us: ; preds = %0 14; CHECK-NEXT: %2 = icmp eq i32 %d, 1 15; CHECK-NEXT: br i1 %2, label %.split.us.split.us, label %.split.us..split.us.split_crit_edge 16 17; CHECK: .split.us..split.us.split_crit_edge: ; preds = %.split.us 18; CHECK-NEXT: br label %.split.us.split 19 20; CHECK: .split.us.split.us: ; preds = %.split.us 21; CHECK-NEXT: br label %loop_begin.us.us 22 23; CHECK: loop_begin.us.us: ; preds = %loop_begin.backedge.us.us, %.split.us.split.us 24; CHECK-NEXT: %var_val.us.us = load i32, i32* %var 25; CHECK-NEXT: switch i32 1, label %second_switch.us.us [ 26; CHECK-NEXT: i32 1, label %inc.us.us 27 28; CHECK: second_switch.us.us: ; preds = %loop_begin.us.us 29; CHECK-NEXT: switch i32 1, label %default.us.us [ 30; CHECK-NEXT: i32 1, label %inc.us.us 31 32; CHECK: inc.us.us: ; preds = %second_switch.us.us, %loop_begin.us.us 33; CHECK-NEXT: call void @incf() [[NOR_NUW:#[0-9]+]] 34; CHECK-NEXT: br label %loop_begin.backedge.us.us 35 36; CHECK: .split.us.split: ; preds = %.split.us..split.us.split_crit_edge 37; CHECK-NEXT: br label %loop_begin.us 38 39; CHECK: loop_begin.us: ; preds = %loop_begin.backedge.us, %.split.us.split 40; CHECK-NEXT: %var_val.us = load i32, i32* %var 41; CHECK-NEXT: switch i32 1, label %second_switch.us [ 42; CHECK-NEXT: i32 1, label %inc.us 43 44; CHECK: second_switch.us: ; preds = %loop_begin.us 45; CHECK-NEXT: switch i32 %d, label %default.us [ 46; CHECK-NEXT: i32 1, label %second_switch.us.inc.us_crit_edge 47; CHECK-NEXT: ] 48 49; CHECK: second_switch.us.inc.us_crit_edge: ; preds = %second_switch.us 50; CHECK-NEXT: br i1 true, label %us-unreachable8, label %inc.us 51 52; CHECK: inc.us: ; preds = %second_switch.us.inc.us_crit_edge, %loop_begin.us 53; CHECK-NEXT: call void @incf() [[NOR_NUW]] 54; CHECK-NEXT: br label %loop_begin.backedge.us 55 56; CHECK: .split: ; preds = %..split_crit_edge 57; CHECK-NEXT: %3 = icmp eq i32 %d, 1 58; CHECK-NEXT: br i1 %3, label %.split.split.us, label %.split..split.split_crit_edge 59 60; CHECK: .split..split.split_crit_edge: ; preds = %.split 61; CHECK-NEXT: br label %.split.split 62 63; CHECK: .split.split.us: ; preds = %.split 64; CHECK-NEXT: br label %loop_begin.us1 65 66; CHECK: loop_begin.us1: ; preds = %loop_begin.backedge.us6, %.split.split.us 67; CHECK-NEXT: %var_val.us2 = load i32, i32* %var 68; CHECK-NEXT: switch i32 %c, label %second_switch.us3 [ 69; CHECK-NEXT: i32 1, label %loop_begin.inc_crit_edge.us 70; CHECK-NEXT: ] 71 72; CHECK: second_switch.us3: ; preds = %loop_begin.us1 73; CHECK-NEXT: switch i32 1, label %default.us5 [ 74; CHECK-NEXT: i32 1, label %inc.us4 75; CHECK-NEXT: ] 76 77; CHECK: inc.us4: ; preds = %loop_begin.inc_crit_edge.us, %second_switch.us3 78; CHECK-NEXT: call void @incf() [[NOR_NUW]] 79; CHECK-NEXT: br label %loop_begin.backedge.us6 80 81; CHECK: loop_begin.inc_crit_edge.us: ; preds = %loop_begin.us1 82; CHECK-NEXT: br i1 true, label %us-unreachable.us-lcssa.us, label %inc.us4 83 84; CHECK: .split.split: ; preds = %.split..split.split_crit_edge 85; CHECK-NEXT: br label %loop_begin 86 87; CHECK: loop_begin: ; preds = %loop_begin.backedge, %.split.split 88; CHECK-NEXT: %var_val = load i32, i32* %var 89; CHECK-NEXT: switch i32 %c, label %second_switch [ 90; CHECK-NEXT: i32 1, label %loop_begin.inc_crit_edge 91; CHECK-NEXT: ] 92 93; CHECK: loop_begin.inc_crit_edge: ; preds = %loop_begin 94; CHECK-NEXT: br i1 true, label %us-unreachable.us-lcssa, label %inc 95 96; CHECK: second_switch: ; preds = %loop_begin 97; CHECK-NEXT: switch i32 %d, label %default [ 98; CHECK-NEXT: i32 1, label %second_switch.inc_crit_edge 99; CHECK-NEXT: ] 100 101; CHECK: second_switch.inc_crit_edge: ; preds = %second_switch 102; CHECK-NEXT: br i1 true, label %us-unreachable7, label %inc 103 104 105define i32 @test(i32* %var) { 106 %mem = alloca i32 107 store i32 2, i32* %mem 108 %c = load i32, i32* %mem 109 %d = load i32, i32* %mem 110 111 br label %loop_begin 112 113loop_begin: 114 115 %var_val = load i32, i32* %var 116 117 switch i32 %c, label %second_switch [ 118 i32 1, label %inc 119 ] 120 121second_switch: 122 switch i32 %d, label %default [ 123 i32 1, label %inc 124 ] 125 126inc: 127 call void @incf() noreturn nounwind 128 br label %loop_begin 129 130default: 131 br label %loop_begin 132 133loop_exit: 134 ret i32 0 135} 136 137declare void @incf() noreturn 138declare void @decf() noreturn 139 140; CHECK: attributes #0 = { noreturn } 141; CHECK: attributes [[NOR_NUW]] = { noreturn nounwind } 142