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|
; RUN: opt -objc-arc-contract -S < %s | FileCheck %s
target datalayout = "e-p:64:64:64"
declare i8* @objc_retain(i8*)
declare void @objc_release(i8*)
declare i8* @objc_autorelease(i8*)
declare i8* @objc_autoreleaseReturnValue(i8*)
declare i8* @objc_retainAutoreleasedReturnValue(i8*)
declare void @use_pointer(i8*)
declare i8* @returner()
declare void @callee()
; CHECK-LABEL: define void @test0(
; CHECK: call void @use_pointer(i8* %0)
; CHECK: }
define void @test0(i8* %x) nounwind {
entry:
%0 = call i8* @objc_retain(i8* %x) nounwind
call void @use_pointer(i8* %x)
ret void
}
; CHECK-LABEL: define void @test1(
; CHECK: call void @use_pointer(i8* %0)
; CHECK: }
define void @test1(i8* %x) nounwind {
entry:
%0 = call i8* @objc_autorelease(i8* %x) nounwind
call void @use_pointer(i8* %x)
ret void
}
; Merge objc_retain and objc_autorelease into objc_retainAutorelease.
; CHECK-LABEL: define void @test2(
; CHECK: tail call i8* @objc_retainAutorelease(i8* %x) [[NUW:#[0-9]+]]
; CHECK: }
define void @test2(i8* %x) nounwind {
entry:
%0 = tail call i8* @objc_retain(i8* %x) nounwind
call i8* @objc_autorelease(i8* %0) nounwind
call void @use_pointer(i8* %x)
ret void
}
; Same as test2 but the value is returned. Do an RV optimization.
; CHECK-LABEL: define i8* @test2b(
; CHECK: tail call i8* @objc_retainAutoreleaseReturnValue(i8* %x) [[NUW]]
; CHECK: }
define i8* @test2b(i8* %x) nounwind {
entry:
%0 = tail call i8* @objc_retain(i8* %x) nounwind
tail call i8* @objc_autoreleaseReturnValue(i8* %0) nounwind
ret i8* %x
}
; Merge a retain,autorelease pair around a call.
; CHECK-LABEL: define void @test3(
; CHECK: tail call i8* @objc_retainAutorelease(i8* %x) [[NUW]]
; CHECK: @use_pointer(i8* %0)
; CHECK: }
define void @test3(i8* %x, i64 %n) {
entry:
tail call i8* @objc_retain(i8* %x) nounwind
call void @use_pointer(i8* %x)
call i8* @objc_autorelease(i8* %x) nounwind
ret void
}
; Trivial retain,autorelease pair with intervening call, but it's post-dominated
; by another release. The retain and autorelease can be merged.
; CHECK-LABEL: define void @test4(
; CHECK-NEXT: entry:
; CHECK-NEXT: @objc_retainAutorelease(i8* %x) [[NUW]]
; CHECK-NEXT: @use_pointer
; CHECK-NEXT: @objc_release
; CHECK-NEXT: ret void
; CHECK-NEXT: }
define void @test4(i8* %x, i64 %n) {
entry:
tail call i8* @objc_retain(i8* %x) nounwind
call void @use_pointer(i8* %x)
call i8* @objc_autorelease(i8* %x) nounwind
tail call void @objc_release(i8* %x) nounwind
ret void
}
; Don't merge retain and autorelease if they're not control-equivalent.
; CHECK-LABEL: define void @test5(
; CHECK: tail call i8* @objc_retain(i8* %p) [[NUW]]
; CHECK: true:
; CHECK: call i8* @objc_autorelease(i8* %0) [[NUW]]
; CHECK: }
define void @test5(i8* %p, i1 %a) {
entry:
tail call i8* @objc_retain(i8* %p) nounwind
br i1 %a, label %true, label %false
true:
call i8* @objc_autorelease(i8* %p) nounwind
call void @use_pointer(i8* %p)
ret void
false:
ret void
}
; Don't eliminate objc_retainAutoreleasedReturnValue by merging it into
; an objc_autorelease.
; TODO? Merge objc_retainAutoreleasedReturnValue and objc_autorelease into
; objc_retainAutoreleasedReturnValueAutorelease and merge
; objc_retainAutoreleasedReturnValue and objc_autoreleaseReturnValue
; into objc_retainAutoreleasedReturnValueAutoreleaseReturnValue?
; Those entrypoints don't exist yet though.
; CHECK-LABEL: define i8* @test6(
; CHECK: call i8* @objc_retainAutoreleasedReturnValue(i8* %p) [[NUW]]
; CHECK: %t = tail call i8* @objc_autoreleaseReturnValue(i8* %1) [[NUW]]
; CHECK: }
define i8* @test6() {
%p = call i8* @returner()
tail call i8* @objc_retainAutoreleasedReturnValue(i8* %p) nounwind
%t = tail call i8* @objc_autoreleaseReturnValue(i8* %p) nounwind
call void @use_pointer(i8* %t)
ret i8* %t
}
; Don't spoil the RV optimization.
; CHECK: define i8* @test7(i8* %p)
; CHECK: tail call i8* @objc_retain(i8* %p)
; CHECK: call void @use_pointer(i8* %1)
; CHECK: tail call i8* @objc_autoreleaseReturnValue(i8* %1)
; CHECK: ret i8* %2
; CHECK-NEXT: }
define i8* @test7(i8* %p) {
%1 = tail call i8* @objc_retain(i8* %p)
call void @use_pointer(i8* %p)
%2 = tail call i8* @objc_autoreleaseReturnValue(i8* %p)
ret i8* %p
}
; Do the return value substitution for PHI nodes too.
; CHECK-LABEL: define i8* @test8(
; CHECK: %retval = phi i8* [ %p, %if.then ], [ null, %entry ]
; CHECK: }
define i8* @test8(i1 %x, i8* %c) {
entry:
br i1 %x, label %return, label %if.then
if.then: ; preds = %entry
%p = call i8* @objc_retain(i8* %c) nounwind
br label %return
return: ; preds = %if.then, %entry
%retval = phi i8* [ %c, %if.then ], [ null, %entry ]
ret i8* %retval
}
; Kill calls to @clang.arc.use(...)
; CHECK-LABEL: define void @test9(
; CHECK-NOT: clang.arc.use
; CHECK: }
define void @test9(i8* %a, i8* %b) {
call void (...)* @clang.arc.use(i8* %a, i8* %b) nounwind
ret void
}
; Turn objc_retain into objc_retainAutoreleasedReturnValue if its operand
; is a return value.
; CHECK: define void @test10()
; CHECK: tail call i8* @objc_retainAutoreleasedReturnValue(i8* %p)
define void @test10() {
%p = call i8* @returner()
tail call i8* @objc_retain(i8* %p) nounwind
ret void
}
; Convert objc_retain to objc_retainAutoreleasedReturnValue if its
; argument is a return value.
; CHECK-LABEL: define void @test11(
; CHECK-NEXT: %y = call i8* @returner()
; CHECK-NEXT: tail call i8* @objc_retainAutoreleasedReturnValue(i8* %y) [[NUW]]
; CHECK-NEXT: ret void
define void @test11() {
%y = call i8* @returner()
tail call i8* @objc_retain(i8* %y) nounwind
ret void
}
; Don't convert objc_retain to objc_retainAutoreleasedReturnValue if its
; argument is not a return value.
; CHECK-LABEL: define void @test12(
; CHECK-NEXT: tail call i8* @objc_retain(i8* %y) [[NUW]]
; CHECK-NEXT: ret void
; CHECK-NEXT: }
define void @test12(i8* %y) {
tail call i8* @objc_retain(i8* %y) nounwind
ret void
}
; Don't Convert objc_retain to objc_retainAutoreleasedReturnValue if it
; isn't next to the call providing its return value.
; CHECK-LABEL: define void @test13(
; CHECK-NEXT: %y = call i8* @returner()
; CHECK-NEXT: call void @callee()
; CHECK-NEXT: tail call i8* @objc_retain(i8* %y) [[NUW]]
; CHECK-NEXT: ret void
; CHECK-NEXT: }
define void @test13() {
%y = call i8* @returner()
call void @callee()
tail call i8* @objc_retain(i8* %y) nounwind
ret void
}
declare void @clang.arc.use(...) nounwind
; CHECK: attributes [[NUW]] = { nounwind }
|
