2011-11-18-TwoSwitches.ll [plain text]
; RUN: opt -loop-unswitch -loop-unswitch-threshold 1000 -disable-output -stats -info-output-file - < %s | FileCheck --check-prefix=STATS %s
; RUN: opt -S -loop-unswitch -loop-unswitch-threshold 1000 -verify-loop-info -verify-dom-info %s | FileCheck %s
; STATS: 1 loop-simplify - Number of pre-header or exit blocks inserted
; STATS: 3 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: %2 = icmp eq i32 %d, 1
; CHECK-NEXT: br i1 %2, label %.split.us.split.us, label %.split.us..split.us.split_crit_edge
; CHECK: .split.us..split.us.split_crit_edge: ; preds = %.split.us
; CHECK-NEXT: br label %.split.us.split
; CHECK: .split.us.split.us: ; preds = %.split.us
; CHECK-NEXT: br label %loop_begin.us.us
; CHECK: loop_begin.us.us: ; preds = %loop_begin.backedge.us.us, %.split.us.split.us
; CHECK-NEXT: %var_val.us.us = load i32* %var
; CHECK-NEXT: switch i32 1, label %second_switch.us.us [
; CHECK-NEXT: i32 1, label %inc.us.us
; CHECK: second_switch.us.us: ; preds = %loop_begin.us.us
; CHECK-NEXT: switch i32 1, label %default.us.us [
; CHECK-NEXT: i32 1, label %inc.us.us
; CHECK: inc.us.us: ; preds = %second_switch.us.us, %loop_begin.us.us
; CHECK-NEXT: call void @incf() noreturn nounwind
; CHECK-NEXT: br label %loop_begin.backedge.us.us
; CHECK: .split.us.split: ; preds = %.split.us..split.us.split_crit_edge
; CHECK-NEXT: br label %loop_begin.us
; CHECK: loop_begin.us: ; preds = %loop_begin.backedge.us, %.split.us.split
; CHECK-NEXT: %var_val.us = load i32* %var
; CHECK-NEXT: 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 %second_switch.us.inc.us_crit_edge
; CHECK-NEXT: ]
; CHECK: second_switch.us.inc.us_crit_edge: ; preds = %second_switch.us
; CHECK-NEXT: br i1 true, label %us-unreachable8, label %inc.us
; CHECK: inc.us: ; preds = %second_switch.us.inc.us_crit_edge, %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: %3 = icmp eq i32 %d, 1
; CHECK-NEXT: br i1 %3, 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.us6, %.split.split.us
; CHECK-NEXT: %var_val.us2 = load i32* %var
; CHECK-NEXT: switch i32 %c, label %second_switch.us3 [
; CHECK-NEXT: i32 1, label %loop_begin.inc_crit_edge.us
; CHECK-NEXT: ]
; CHECK: second_switch.us3: ; preds = %loop_begin.us1
; CHECK-NEXT: switch i32 1, label %default.us5 [
; CHECK-NEXT: i32 1, label %inc.us4
; CHECK-NEXT: ]
; CHECK: inc.us4: ; preds = %loop_begin.inc_crit_edge.us, %second_switch.us3
; CHECK-NEXT: call void @incf() noreturn nounwind
; CHECK-NEXT: br label %loop_begin.backedge.us6
; CHECK: loop_begin.inc_crit_edge.us: ; preds = %loop_begin.us1
; CHECK-NEXT: br i1 true, label %us-unreachable.us-lcssa.us, label %inc.us4
; 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 %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.us-lcssa, label %inc
; CHECK: second_switch: ; preds = %loop_begin
; CHECK-NEXT: switch i32 %d, label %default [
; CHECK-NEXT: i32 1, label %second_switch.inc_crit_edge
; CHECK-NEXT: ]
; CHECK: second_switch.inc_crit_edge: ; preds = %second_switch
; CHECK-NEXT: br i1 true, label %us-unreachable7, label %inc
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