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|
; RUN: opt -passes='loop(unswitch),verify<loops>' -S < %s | FileCheck %s
declare void @some_func() noreturn
; This test contains two trivial unswitch condition in one loop.
; LoopUnswitch pass should be able to unswitch the second one
; after unswitching the first one.
define i32 @test1(i32* %var, i1 %cond1, i1 %cond2) {
; CHECK-LABEL: @test1(
entry:
br label %loop_begin
; CHECK-NEXT: entry:
; CHECK-NEXT: br i1 %{{.*}}, label %entry.split, label %loop_exit.split
;
; CHECK: entry.split:
; CHECK-NEXT: br i1 %{{.*}}, label %entry.split.split, label %loop_exit
;
; CHECK: entry.split.split:
; CHECK-NEXT: br label %loop_begin
loop_begin:
br i1 %cond1, label %continue, label %loop_exit ; first trivial condition
; CHECK: loop_begin:
; CHECK-NEXT: br label %continue
continue:
%var_val = load i32, i32* %var
br i1 %cond2, label %do_something, label %loop_exit ; second trivial condition
; CHECK: continue:
; CHECK-NEXT: load
; CHECK-NEXT: br label %do_something
do_something:
call void @some_func() noreturn nounwind
br label %loop_begin
; CHECK: do_something:
; CHECK-NEXT: call
; CHECK-NEXT: br label %loop_begin
loop_exit:
ret i32 0
; CHECK: loop_exit:
; CHECK-NEXT: br label %loop_exit.split
;
; CHECK: loop_exit.split:
; CHECK-NEXT: ret
}
; Test for two trivially unswitchable switches.
define i32 @test3(i32* %var, i32 %cond1, i32 %cond2) {
; CHECK-LABEL: @test3(
entry:
br label %loop_begin
; CHECK-NEXT: entry:
; CHECK-NEXT: switch i32 %cond1, label %entry.split [
; CHECK-NEXT: i32 0, label %loop_exit1
; CHECK-NEXT: ]
;
; CHECK: entry.split:
; CHECK-NEXT: switch i32 %cond2, label %loop_exit2 [
; CHECK-NEXT: i32 42, label %loop_exit2
; CHECK-NEXT: i32 0, label %entry.split.split
; CHECK-NEXT: ]
;
; CHECK: entry.split.split:
; CHECK-NEXT: br label %loop_begin
loop_begin:
switch i32 %cond1, label %continue [
i32 0, label %loop_exit1
]
; CHECK: loop_begin:
; CHECK-NEXT: br label %continue
continue:
%var_val = load i32, i32* %var
switch i32 %cond2, label %loop_exit2 [
i32 0, label %do_something
i32 42, label %loop_exit2
]
; CHECK: continue:
; CHECK-NEXT: load
; CHECK-NEXT: br label %do_something
do_something:
call void @some_func() noreturn nounwind
br label %loop_begin
; CHECK: do_something:
; CHECK-NEXT: call
; CHECK-NEXT: br label %loop_begin
loop_exit1:
ret i32 0
; CHECK: loop_exit1:
; CHECK-NEXT: ret
loop_exit2:
ret i32 0
; CHECK: loop_exit2:
; CHECK-NEXT: ret
;
; We shouldn't have any unreachable blocks here because the unswitched switches
; turn into branches instead.
; CHECK-NOT: unreachable
}
; Test for a trivially unswitchable switch with multiple exiting cases and
; multiple looping cases.
define i32 @test4(i32* %var, i32 %cond1, i32 %cond2) {
; CHECK-LABEL: @test4(
entry:
br label %loop_begin
; CHECK-NEXT: entry:
; CHECK-NEXT: switch i32 %cond2, label %loop_exit2 [
; CHECK-NEXT: i32 13, label %loop_exit1
; CHECK-NEXT: i32 42, label %loop_exit3
; CHECK-NEXT: i32 0, label %entry.split
; CHECK-NEXT: i32 1, label %entry.split
; CHECK-NEXT: i32 2, label %entry.split
; CHECK-NEXT: ]
;
; CHECK: entry.split:
; CHECK-NEXT: br label %loop_begin
loop_begin:
%var_val = load i32, i32* %var
switch i32 %cond2, label %loop_exit2 [
i32 0, label %loop0
i32 1, label %loop1
i32 13, label %loop_exit1
i32 2, label %loop2
i32 42, label %loop_exit3
]
; CHECK: loop_begin:
; CHECK-NEXT: load
; CHECK-NEXT: switch i32 %cond2, label %[[UNREACHABLE:.*]] [
; CHECK-NEXT: i32 0, label %loop0
; CHECK-NEXT: i32 1, label %loop1
; CHECK-NEXT: i32 2, label %loop2
; CHECK-NEXT: ]
loop0:
call void @some_func() noreturn nounwind
br label %loop_latch
; CHECK: loop0:
; CHECK-NEXT: call
; CHECK-NEXT: br label %loop_latch
loop1:
call void @some_func() noreturn nounwind
br label %loop_latch
; CHECK: loop1:
; CHECK-NEXT: call
; CHECK-NEXT: br label %loop_latch
loop2:
call void @some_func() noreturn nounwind
br label %loop_latch
; CHECK: loop2:
; CHECK-NEXT: call
; CHECK-NEXT: br label %loop_latch
loop_latch:
br label %loop_begin
; CHECK: loop_latch:
; CHECK-NEXT: br label %loop_begin
loop_exit1:
ret i32 0
; CHECK: loop_exit1:
; CHECK-NEXT: ret
loop_exit2:
ret i32 0
; CHECK: loop_exit2:
; CHECK-NEXT: ret
loop_exit3:
ret i32 0
; CHECK: loop_exit3:
; CHECK-NEXT: ret
;
; CHECK: [[UNREACHABLE]]:
; CHECK-NEXT: unreachable
}
|
