; RUN: opt -passes=jump-threading -S < %s | FileCheck %s
declare i32 @f1()
declare i32 @f2()
declare void @f3()
define i32 @test1(i1 %cond) {
; CHECK-LABEL: @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-LABEL: @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-LABEL: @test3(
; CHECK-NEXT: T1:
; CHECK-NEXT: ret i32 42
br i1 undef, label %T1, label %F1
T1:
ret i32 42
F1:
ret i32 17
}
define i32 @test4(i1 %cond, i1 %cond2) {
; CHECK-LABEL: @test4(
br i1 %cond, label %T1, label %F1
T1:
; CHECK: %v1 = call i32 @f1()
; CHECK-NEXT: br label %T
%v1 = call i32 @f1()
br label %Merge
F1:
%v2 = call i32 @f2()
; CHECK: %v2 = call i32 @f2()
; CHECK-NEXT: br i1 %cond2,
br label %Merge
Merge:
%A = phi i1 [undef, %T1], [%cond2, %F1]
%B = phi i32 [%v1, %T1], [%v2, %F1]
br i1 %A, label %T2, label %F2
T2:
call void @f3()
ret i32 %B
F2:
ret i32 %B
}
;; This tests that the branch in 'merge' can be cloned up into T1.
define i32 @test5(i1 %cond, i1 %cond2) {
; CHECK-LABEL: @test5(
br i1 %cond, label %T1, label %F1
T1:
; CHECK: T1:
; CHECK-NEXT: %v1 = call i32 @f1()
; CHECK-NEXT: %cond3 = icmp eq i32 %v1, 412
; CHECK-NEXT: br i1 %cond3, label %T2, label %F2
%v1 = call i32 @f1()
%cond3 = icmp eq i32 %v1, 412
br label %Merge
F1:
%v2 = call i32 @f2()
br label %Merge
Merge:
%A = phi i1 [%cond3, %T1], [%cond2, %F1]
%B = phi i32 [%v1, %T1], [%v2, %F1]
br i1 %A, label %T2, label %F2
T2:
call void @f3()
ret i32 %B
F2:
ret i32 %B
}
;; Lexically duplicated conditionals should be threaded.
define i32 @test6(i32 %A) {
; CHECK-LABEL: @test6(
%tmp455 = icmp eq i32 %A, 42
br i1 %tmp455, label %BB1, label %BB2
; CHECK: call i32 @f2()
; CHECK-NEXT: ret i32 3
; CHECK: call i32 @f1()
; CHECK-NOT: br
; CHECK: call void @f3()
; CHECK-NOT: br
; CHECK: ret i32 4
BB2:
call i32 @f1()
br label %BB1
BB1:
%tmp459 = icmp eq i32 %A, 42
br i1 %tmp459, label %BB3, label %BB4
BB3:
call i32 @f2()
ret i32 3
BB4:
call void @f3()
ret i32 4
}
;; This tests that the branch in 'merge' can be cloned up into T1.
;; rdar://7367025
define i32 @test7(i1 %cond, i1 %cond2) {
Entry:
; CHECK-LABEL: @test7(
%v1 = call i32 @f1()
br i1 %cond, label %Merge, label %F1
F1:
%v2 = call i32 @f2()
br label %Merge
Merge:
%B = phi i32 [%v1, %Entry], [%v2, %F1]
%M = icmp ne i32 %B, %v1
%N = icmp eq i32 %B, 47
%O = and i1 %M, %N
br i1 %O, label %T2, label %F2
; CHECK: Merge:
; CHECK-NOT: phi
; CHECK-NEXT: %v2 = call i32 @f2()
T2:
call void @f3()
ret i32 %B
F2:
ret i32 %B
; CHECK: F2:
; CHECK-NEXT: phi i32
}
declare i1 @test8a()
define i32 @test8b(i1 %cond, i1 %cond2) {
; CHECK-LABEL: @test8b(
T0:
%A = call i1 @test8a()
br i1 %A, label %T1, label %F1
; CHECK: T0:
; CHECK-NEXT: call
; CHECK-NEXT: br i1 %A, label %T1, label %Y
T1:
%B = call i1 @test8a()
br i1 %B, label %T2, label %F1
; CHECK: T1:
; CHECK-NEXT: call
; CHECK-NEXT: br i1 %B, label %T2, label %Y
T2:
%C = call i1 @test8a()
br i1 %cond, label %T3, label %F1
; CHECK: T2:
; CHECK-NEXT: call
; CHECK-NEXT: br i1 %cond, label %T3, label %Y
T3:
ret i32 0
F1:
%D = phi i32 [0, %T0], [0, %T1], [1, %T2]
%E = icmp eq i32 %D, 1
%F = and i1 %E, %cond
br i1 %F, label %X, label %Y
X:
call i1 @test8a()
ret i32 1
Y:
ret i32 2
}
;;; Verify that we can handle constraint propagation through "xor x, 1".
define i32 @test9(i1 %cond, i1 %cond2) {
Entry:
; CHECK-LABEL: @test9(
%v1 = call i32 @f1()
br i1 %cond, label %Merge, label %F1
; CHECK: Entry:
; CHECK-NEXT: %v1 = call i32 @f1()
; CHECK-NEXT: br i1 %cond, label %F2, label %Merge
F1:
%v2 = call i32 @f2()
br label %Merge
Merge:
%B = phi i32 [%v1, %Entry], [%v2, %F1]
%M = icmp eq i32 %B, %v1
%M1 = xor i1 %M, 1
%N = icmp eq i32 %B, 47
%O = and i1 %M1, %N
br i1 %O, label %T2, label %F2
; CHECK: Merge:
; CHECK-NOT: phi
; CHECK-NEXT: %v2 = call i32 @f2()
T2:
%Q = zext i1 %M to i32
ret i32 %Q
F2:
ret i32 %B
; CHECK: F2:
; CHECK-NEXT: phi i32
}
; CHECK: @test10
declare i32 @test10f1()
declare i32 @test10f2()
declare void @test10f3()
;; Non-local condition threading.
define i32 @test10g(i1 %cond) {
; CHECK-LABEL: @test10g(
; CHECK-NEXT: br i1 %cond, label %T2, label %F2
br i1 %cond, label %T1, label %F1
T1:
%v1 = call i32 @test10f1()
br label %Merge
; CHECK: %v1 = call i32 @test10f1()
; CHECK-NEXT: call void @f3()
; CHECK-NEXT: ret i32 %v1
F1:
%v2 = call i32 @test10f2()
br label %Merge
Merge:
%B = phi i32 [%v1, %T1], [%v2, %F1]
br i1 %cond, label %T2, label %F2
T2:
call void @f3()
ret i32 %B
F2:
ret i32 %B
}
; Impossible conditional constraints should get threaded. BB3 is dead here.
define i32 @test11(i32 %A) {
; CHECK-LABEL: @test11(
; CHECK-NEXT: icmp
; CHECK-NEXT: br i1 %tmp455, label %BB4, label %BB2
%tmp455 = icmp eq i32 %A, 42
br i1 %tmp455, label %BB1, label %BB2
BB2:
; CHECK: call i32 @f1()
; CHECK-NEXT: ret i32 %C
%C = call i32 @f1()
ret i32 %C
BB1:
%tmp459 = icmp eq i32 %A, 43
br i1 %tmp459, label %BB3, label %BB4
BB3:
call i32 @f2()
ret i32 3
BB4:
call void @f3()
ret i32 4
}
;; Correlated value through boolean expression. GCC PR18046.
define void @test12(i32 %A) {
; CHECK-LABEL: @test12(
entry:
%cond = icmp eq i32 %A, 0
br i1 %cond, label %bb, label %bb1
; Should branch to the return block instead of through BB1.
; CHECK: entry:
; CHECK-NEXT: %cond = icmp eq i32 %A, 0
; CHECK-NEXT: br i1 %cond, label %bb1, label %return
bb:
%B = call i32 @test10f2()
br label %bb1
bb1:
%C = phi i32 [ %A, %entry ], [ %B, %bb ]
%cond4 = icmp eq i32 %C, 0
br i1 %cond4, label %bb2, label %return
; CHECK: bb1:
; CHECK-NEXT: %B = call i32 @test10f2()
; CHECK-NEXT: %cond4 = icmp eq i32 %B, 0
; CHECK-NEXT: br i1 %cond4, label %bb2, label %return
bb2:
%D = call i32 @test10f2()
ret void
return:
ret void
}
;; Duplicate condition to avoid xor of cond.
;; rdar://7391699
define i32 @test13(i1 %cond, i1 %cond2) {
Entry:
; CHECK-LABEL: @test13(
%v1 = call i32 @f1()
br i1 %cond, label %Merge, label %F1
F1:
br label %Merge
Merge:
%B = phi i1 [true, %Entry], [%cond2, %F1]
%C = phi i32 [192, %Entry], [%v1, %F1]
%M = icmp eq i32 %C, 192
%N = xor i1 %B, %M
br i1 %N, label %T2, label %F2
T2:
ret i32 123
F2:
ret i32 %v1
; CHECK: br i1 %cond, label %F2, label %Merge
; CHECK: Merge:
; CHECK-NEXT: %M = icmp eq i32 %v1, 192
; CHECK-NEXT: %N = xor i1 %cond2, %M
; CHECK-NEXT: br i1 %N, label %T2, label %F2
}
; CHECK-LABEL: @test14(
define i32 @test14(i32 %in) {
entry:
%A = icmp eq i32 %in, 0
; CHECK: br i1 %A, label %right_ret, label %merge
br i1 %A, label %left, label %right
; CHECK-NOT: left:
left:
br label %merge
; CHECK-NOT: right:
right:
%B = call i32 @f1()
br label %merge
merge:
; CHECK-NOT: %C = phi i32 [%in, %left], [%B, %right]
%C = phi i32 [%in, %left], [%B, %right]
%D = add i32 %C, 1
%E = icmp eq i32 %D, 2
br i1 %E, label %left_ret, label %right_ret
; CHECK: left_ret:
left_ret:
ret i32 0
right_ret:
ret i32 1
}
; PR5652
; CHECK-LABEL: @test15(
define i32 @test15(i32 %len) {
entry:
; CHECK: icmp ult i32 %len, 13
%tmp = icmp ult i32 %len, 13
br i1 %tmp, label %check, label %exit0
exit0:
ret i32 0
check:
%tmp9 = icmp ult i32 %len, 21
br i1 %tmp9, label %exit1, label %exit2
exit2:
; CHECK-NOT: ret i32 2
ret i32 2
exit1:
ret i32 1
; CHECK: }
}
;;; Verify that we can handle constraint propagation through cast.
define i32 @test16(i1 %cond) {
Entry:
; CHECK-LABEL: @test16(
br i1 %cond, label %Merge, label %F1
; CHECK: Entry:
; CHECK-NEXT: br i1 %cond, label %F2, label %Merge
F1:
%v1 = call i32 @f1()
br label %Merge
Merge:
%B = phi i32 [0, %Entry], [%v1, %F1]
%M = icmp eq i32 %B, 0
%M1 = zext i1 %M to i32
%N = icmp eq i32 %M1, 0
br i1 %N, label %T2, label %F2
; CHECK: Merge:
; CHECK-NOT: phi
; CHECK-NEXT: %v1 = call i32 @f1()
T2:
%Q = call i32 @f2()
ret i32 %Q
F2:
ret i32 %B
; CHECK: F2:
; CHECK-NEXT: phi i32
}
; In this test we check that block duplication is inhibited by the presence
; of a function with the 'noduplicate' attribute.
declare void @g()
declare void @j()
declare void @k()
; CHECK-LABEL: define void @h(i32 %p) {
define void @h(i32 %p) {
%x = icmp ult i32 %p, 5
br i1 %x, label %l1, label %l2
l1:
call void @j()
br label %l3
l2:
call void @k()
br label %l3
l3:
; CHECK: call void @g() [[$NOD:#[0-9]+]]
; CHECK-NOT: call void @g() [[$NOD]]
call void @g() noduplicate
%y = icmp ult i32 %p, 5
br i1 %y, label %l4, label %l5
l4:
call void @j()
ret void
l5:
call void @k()
ret void
; CHECK: }
}
define i1 @trunc_switch(i1 %arg) {
; CHECK-LABEL: @trunc_switch
top:
; CHECK: br i1 %arg, label %exitA, label %exitB
br i1 %arg, label %common, label %B
B:
br label %common
common:
%phi = phi i8 [ 2, %B ], [ 1, %top ]
%trunc = trunc i8 %phi to i2
; CHECK-NOT: switch
switch i2 %trunc, label %unreach [
i2 1, label %exitA
i2 -2, label %exitB
]
unreach:
unreachable
exitA:
ret i1 true
exitB:
ret i1 false
}
; CHECK-LABEL: define void @h_con(i32 %p) {
define void @h_con(i32 %p) {
%x = icmp ult i32 %p, 5
br i1 %x, label %l1, label %l2
l1:
call void @j()
br label %l3
l2:
call void @k()
br label %l3
l3:
; CHECK: call void @g() [[$CON:#[0-9]+]]
; CHECK-NOT: call void @g() [[$CON]]
call void @g() convergent
%y = icmp ult i32 %p, 5
br i1 %y, label %l4, label %l5
l4:
call void @j()
ret void
l5:
call void @k()
ret void
; CHECK: }
}
; CHECK: attributes [[$NOD]] = { noduplicate }
; CHECK: attributes [[$CON]] = { convergent }
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