test/Transforms/JumpThreading/basic.ll

; RUN: opt < %s -jump-threading -S | FileCheck %s
; There should be no uncond branches left.
; RUN: opt < %s -jump-threading -S | not grep {br label}

declare i32 @f1()
declare i32 @f2()
declare void @f3()

define i32 @test1(i1 %cond) {
; CHECK: @test1

	br i1 %cond, label %T1, label %F1

T1:
	%v1 = call i32 @f1()
	br label %Merge

F1:
	%v2 = call i32 @f2()
	br label %Merge

Merge:
	%A = phi i1 [true, %T1], [false, %F1]
	%B = phi i32 [%v1, %T1], [%v2, %F1]
	br i1 %A, label %T2, label %F2

T2:
; CHECK: T2:
; CHECK: ret i32 %v1
	call void @f3()
	ret i32 %B

F2:
; CHECK: F2:
; CHECK: ret i32 %v2
	ret i32 %B
}


;; cond is known false on Entry -> F1 edge!
define i32 @test2(i1 %cond) {
; CHECK: @test2
Entry:
	br i1 %cond, label %T1, label %F1

T1:
; CHECK: %v1 = call i32 @f1()
; CHECK: ret i32 47
	%v1 = call i32 @f1()
	br label %Merge

F1:
	br i1 %cond, label %Merge, label %F2

Merge:
	%B = phi i32 [47, %T1], [192, %F1]
	ret i32 %B

F2:
	call void @f3()
	ret i32 12
}


; Undef handling.
define i32 @test3(i1 %cond) {
; CHECK: @test3
; CHECK-NEXT: T1:
; CHECK-NEXT: ret i32 42
	br i1 undef, label %T1, label %F1

T1:
	ret i32 42

F1:
	ret i32 17
}