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; REQUIRES: asserts
; RUN: opt -loop-unswitch -disable-output -stats -info-output-file - < %s | FileCheck --check-prefix=STATS %s
; RUN: opt -S -loop-unswitch -verify-loop-info -verify-dom-info < %s | FileCheck %s
; STATS: 1 loop-simplify - Number of pre-header or exit blocks inserted
; STATS: 2 loop-unswitch - Number of switches unswitched
; CHECK: %1 = icmp eq i32 %c, 1
; CHECK-NEXT: br i1 %1, label %.split.us, label %..split_crit_edge
; CHECK: ..split_crit_edge: ; preds = %0
; CHECK-NEXT: br label %.split
; CHECK: .split.us: ; preds = %0
; CHECK-NEXT: br label %loop_begin.us
; CHECK: loop_begin.us: ; preds = %loop_begin.backedge.us, %.split.us
; CHECK-NEXT: %var_val.us = load i32* %var
; CHECK-NEXT: switch i32 1, label %default.us-lcssa.us [
; CHECK-NEXT: i32 1, label %inc.us
; CHECK: inc.us: ; preds = %loop_begin.us
; CHECK-NEXT: call void @incf() [[NOR_NUW:#[0-9]+]]
; CHECK-NEXT: br label %loop_begin.backedge.us
; CHECK: .split: ; preds = %..split_crit_edge
; CHECK-NEXT: %2 = icmp eq i32 %c, 2
; CHECK-NEXT: br i1 %2, label %.split.split.us, label %.split..split.split_crit_edge
; CHECK: .split..split.split_crit_edge: ; preds = %.split
; CHECK-NEXT: br label %.split.split
; CHECK: .split.split.us: ; preds = %.split
; CHECK-NEXT: br label %loop_begin.us1
; CHECK: loop_begin.us1: ; preds = %loop_begin.backedge.us5, %.split.split.us
; CHECK-NEXT: %var_val.us2 = load i32* %var
; CHECK-NEXT: switch i32 2, label %default.us-lcssa.us-lcssa.us [
; CHECK-NEXT: i32 1, label %inc.us4
; CHECK-NEXT: i32 2, label %dec.us3
; CHECK-NEXT: ]
; CHECK: dec.us3: ; preds = %loop_begin.us1
; CHECK-NEXT: call void @decf() [[NOR_NUW]]
; CHECK-NEXT: br label %loop_begin.backedge.us5
; CHECK: .split.split: ; preds = %.split..split.split_crit_edge
; CHECK-NEXT: br label %loop_begin
; CHECK: loop_begin: ; preds = %loop_begin.backedge, %.split.split
; CHECK-NEXT: %var_val = load i32* %var
; CHECK-NEXT: switch i32 %c, label %default.us-lcssa.us-lcssa [
; CHECK-NEXT: i32 1, label %inc
; CHECK-NEXT: i32 2, label %dec
; CHECK-NEXT: ]
; CHECK: inc: ; preds = %loop_begin
; CHECK-NEXT: br i1 true, label %us-unreachable.us-lcssa, label %inc.split
; CHECK: dec: ; preds = %loop_begin
; CHECK-NEXT: br i1 true, label %us-unreachable6, label %dec.split
define i32 @test(i32* %var) {
%mem = alloca i32
store i32 2, i32* %mem
%c = load i32* %mem
br label %loop_begin
loop_begin:
%var_val = load i32* %var
switch i32 %c, label %default [
i32 1, label %inc
i32 2, label %dec
]
inc:
call void @incf() noreturn nounwind
br label %loop_begin
dec:
call void @decf() noreturn nounwind
br label %loop_begin
default:
br label %loop_exit
loop_exit:
ret i32 0
}
declare void @incf() noreturn
declare void @decf() noreturn
; CHECK: attributes #0 = { noreturn }
; CHECK: attributes [[NOR_NUW]] = { noreturn nounwind }
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