1 ; REQUIRES: asserts 2 ; RUN: opt -loop-unswitch -loop-unswitch-threshold 13 -disable-output -stats -info-output-file - < %s | FileCheck --check-prefix=STATS %s 3 ; RUN: opt -S -loop-unswitch -loop-unswitch-threshold 13 -verify-loop-info -verify-dom-info < %s | FileCheck %s 4 5 ; STATS: 1 loop-simplify - Number of pre-header or exit blocks inserted 6 ; STATS: 1 loop-unswitch - Number of switches unswitched 7 8 ; ModuleID = '../llvm/test/Transforms/LoopUnswitch/2011-11-18-TwoSwitches.ll' 9 10 ; CHECK: %1 = icmp eq i32 %c, 1 11 ; CHECK-NEXT: br i1 %1, label %.split.us, label %..split_crit_edge 12 13 ; CHECK: ..split_crit_edge: ; preds = %0 14 ; CHECK-NEXT: br label %.split 15 16 ; CHECK: .split.us: ; preds = %0 17 ; CHECK-NEXT: br label %loop_begin.us 18 19 ; CHECK: loop_begin.us: ; preds = %loop_begin.backedge.us, %.split.us 20 ; CHECK: switch i32 1, label %second_switch.us [ 21 ; CHECK-NEXT: i32 1, label %inc.us 22 23 ; CHECK: second_switch.us: ; preds = %loop_begin.us 24 ; CHECK-NEXT: switch i32 %d, label %default.us [ 25 ; CHECK-NEXT: i32 1, label %inc.us 26 ; CHECK-NEXT: ] 27 28 ; CHECK: inc.us: ; preds = %second_switch.us, %loop_begin.us 29 ; CHECK-NEXT: call void @incf() [[NOR_NUW:#[0-9]+]] 30 ; CHECK-NEXT: br label %loop_begin.backedge.us 31 32 ; CHECK: .split: ; preds = %..split_crit_edge 33 ; CHECK-NEXT: br label %loop_begin 34 35 ; CHECK: loop_begin: ; preds = %loop_begin.backedge, %.split 36 ; CHECK: switch i32 %c, label %second_switch [ 37 ; CHECK-NEXT: i32 1, label %loop_begin.inc_crit_edge 38 ; CHECK-NEXT: ] 39 40 ; CHECK: loop_begin.inc_crit_edge: ; preds = %loop_begin 41 ; CHECK-NEXT: br i1 true, label %us-unreachable, label %inc 42 43 ; CHECK: second_switch: ; preds = %loop_begin 44 ; CHECK-NEXT: switch i32 %d, label %default [ 45 ; CHECK-NEXT: i32 1, label %inc 46 ; CHECK-NEXT: ] 47 48 ; CHECK: inc: ; preds = %loop_begin.inc_crit_edge, %second_switch 49 ; CHECK-NEXT: call void @incf() [[NOR_NUW]] 50 ; CHECK-NEXT: br label %loop_begin.backedge 51 52 define i32 @test(i32* %var) { 53 %mem = alloca i32 54 store i32 2, i32* %mem 55 %c = load i32* %mem 56 %d = load i32* %mem 57 58 br label %loop_begin 59 60 loop_begin: 61 62 %var_val = load i32* %var 63 64 switch i32 %c, label %second_switch [ 65 i32 1, label %inc 66 ] 67 68 second_switch: 69 switch i32 %d, label %default [ 70 i32 1, label %inc 71 ] 72 73 inc: 74 call void @incf() noreturn nounwind 75 br label %loop_begin 76 77 default: 78 br label %loop_begin 79 80 loop_exit: 81 ret i32 0 82 } 83 84 declare void @incf() noreturn 85 declare void @decf() noreturn 86 87 ; CHECK: attributes #0 = { noreturn } 88 ; CHECK: attributes [[NOR_NUW]] = { noreturn nounwind } 89