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; RUN: opt < %s -loop-unswitch -loop-unswitch-with-block-frequency -S 2>&1 | FileCheck %s
;; trivial condition should be unswithed regardless of coldness.
define i32 @test1(i1 %cond1, i1 %cond2) !prof !1 {
br i1 %cond1, label %loop_begin, label %loop_exit, !prof !0
loop_begin:
; CHECK: br i1 true, label %continue, label %loop_exit.loopexit
br i1 %cond2, label %continue, label %loop_exit ; trivial condition
continue:
call void @some_func1() noreturn nounwind
br label %loop_begin
loop_exit:
ret i32 0
}
;; cold non-trivial condition should not be unswitched.
define i32 @test2(i32* %var, i1 %cond1, i1 %cond2) !prof !1 {
br i1 %cond1, label %loop_begin, label %loop_exit, !prof !0
loop_begin:
store i32 1, i32* %var
; CHECK: br i1 %cond2, label %continue1, label %continue2
br i1 %cond2, label %continue1, label %continue2 ; non-trivial condition
continue1:
call void @some_func1() noreturn nounwind
br label %joint
continue2:
call void @some_func2() noreturn nounwind
br label %joint
joint:
;; unswitching will duplicate these calls.
call void @some_func3() noreturn nounwind
call void @some_func4() noreturn nounwind
br label %loop_begin
loop_exit:
ret i32 0
}
declare void @some_func1() noreturn
declare void @some_func2() noreturn
declare void @some_func3() noreturn
declare void @some_func4() noreturn
!0 = !{!"branch_weights", i32 1, i32 100000000}
!1 = !{!"function_entry_count", i64 100}
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