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; RUN: opt -loop-unswitch -loop-unswitch-threshold 13 -disable-output -stats -info-output-file - < %s | FileCheck --check-prefix=STATS %s
; RUN: opt -S -loop-unswitch -loop-unswitch-threshold 13 -verify-loop-info -verify-dom-info < %s | FileCheck %s
; STATS: 1 loop-simplify - Number of pre-header or exit blocks inserted
; STATS: 1 loop-unswitch - Number of switches unswitched
; ModuleID = '../llvm/test/Transforms/LoopUnswitch/2011-11-18-TwoSwitches.ll'
; 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: switch i32 1, label %second_switch.us [
; CHECK-NEXT: i32 1, label %inc.us
; CHECK: second_switch.us: ; preds = %loop_begin.us
; CHECK-NEXT: switch i32 %d, label %default.us [
; CHECK-NEXT: i32 1, label %inc.us
; CHECK-NEXT: ]
; CHECK: inc.us: ; preds = %second_switch.us, %loop_begin.us
; CHECK-NEXT: call void @incf() noreturn nounwind
; CHECK-NEXT: br label %loop_begin.backedge.us
; CHECK: .split: ; preds = %..split_crit_edge
; CHECK-NEXT: br label %loop_begin
; CHECK: loop_begin: ; preds = %loop_begin.backedge, %.split
; CHECK: switch i32 %c, label %second_switch [
; CHECK-NEXT: i32 1, label %loop_begin.inc_crit_edge
; CHECK-NEXT: ]
; CHECK: loop_begin.inc_crit_edge: ; preds = %loop_begin
; CHECK-NEXT: br i1 true, label %us-unreachable, label %inc
; CHECK: second_switch: ; preds = %loop_begin
; CHECK-NEXT: switch i32 %d, label %default [
; CHECK-NEXT: i32 1, label %inc
; CHECK-NEXT: ]
; CHECK: inc: ; preds = %loop_begin.inc_crit_edge, %second_switch
; CHECK-NEXT: call void @incf() noreturn nounwind
; CHECK-NEXT: br label %loop_begin.backedge
define i32 @test(i32* %var) {
%mem = alloca i32
store i32 2, i32* %mem
%c = load i32* %mem
%d = load i32* %mem
br label %loop_begin
loop_begin:
%var_val = load i32* %var
switch i32 %c, label %second_switch [
i32 1, label %inc
]
second_switch:
switch i32 %d, label %default [
i32 1, label %inc
]
inc:
call void @incf() noreturn nounwind
br label %loop_begin
default:
br label %loop_begin
loop_exit:
ret i32 0
}
declare void @incf() noreturn
declare void @decf() noreturn
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