declare i8* @objc_retain(i8*)
declare void @objc_release(i8*)
+declare void @use_pointer(i8*)
@x = external global i8*
-; CHECK: define void @test0(
+; CHECK-LABEL: define void @test0(
; CHECK: entry:
-; CHECK-NEXT: call void @objc_storeStrong(i8** @x, i8* %p) nounwind
+; CHECK-NEXT: tail call void @objc_storeStrong(i8** @x, i8* %p) [[NUW:#[0-9]+]]
; CHECK-NEXT: ret void
+; CHECK-NEXT: }
define void @test0(i8* %p) {
entry:
%0 = tail call i8* @objc_retain(i8* %p) nounwind
; CHECK: define void @test1(i8* %p) {
; CHECK-NEXT: entry:
-; CHECK-NEXT: %0 = tail call i8* @objc_retain(i8* %p) nounwind
+; CHECK-NEXT: %0 = tail call i8* @objc_retain(i8* %p) [[NUW]]
; CHECK-NEXT: %tmp = load volatile i8** @x, align 8
; CHECK-NEXT: store i8* %0, i8** @x, align 8
-; CHECK-NEXT: tail call void @objc_release(i8* %tmp) nounwind
+; CHECK-NEXT: tail call void @objc_release(i8* %tmp) [[NUW]]
; CHECK-NEXT: ret void
; CHECK-NEXT: }
define void @test1(i8* %p) {
; CHECK: define void @test2(i8* %p) {
; CHECK-NEXT: entry:
-; CHECK-NEXT: %0 = tail call i8* @objc_retain(i8* %p) nounwind
+; CHECK-NEXT: %0 = tail call i8* @objc_retain(i8* %p) [[NUW]]
; CHECK-NEXT: %tmp = load i8** @x, align 8
; CHECK-NEXT: store volatile i8* %0, i8** @x, align 8
-; CHECK-NEXT: tail call void @objc_release(i8* %tmp) nounwind
+; CHECK-NEXT: tail call void @objc_release(i8* %tmp) [[NUW]]
; CHECK-NEXT: ret void
; CHECK-NEXT: }
define void @test2(i8* %p) {
tail call void @objc_release(i8* %tmp) nounwind
ret void
}
+
+; Don't do this if there's a use of the old pointer value between the store
+; and the release.
+
+; CHECK: define void @test3(i8* %newValue) {
+; CHECK-NEXT: entry:
+; CHECK-NEXT: %x0 = tail call i8* @objc_retain(i8* %newValue) [[NUW]]
+; CHECK-NEXT: %x1 = load i8** @x, align 8
+; CHECK-NEXT: store i8* %x0, i8** @x, align 8
+; CHECK-NEXT: tail call void @use_pointer(i8* %x1), !clang.arc.no_objc_arc_exceptions !0
+; CHECK-NEXT: tail call void @objc_release(i8* %x1) [[NUW]], !clang.imprecise_release !0
+; CHECK-NEXT: ret void
+; CHECK-NEXT: }
+define void @test3(i8* %newValue) {
+entry:
+ %x0 = tail call i8* @objc_retain(i8* %newValue) nounwind
+ %x1 = load i8** @x, align 8
+ store i8* %newValue, i8** @x, align 8
+ tail call void @use_pointer(i8* %x1), !clang.arc.no_objc_arc_exceptions !0
+ tail call void @objc_release(i8* %x1) nounwind, !clang.imprecise_release !0
+ ret void
+}
+
+; Like test3, but with an icmp use instead of a call, for good measure.
+
+; CHECK: define i1 @test4(i8* %newValue, i8* %foo) {
+; CHECK-NEXT: entry:
+; CHECK-NEXT: %x0 = tail call i8* @objc_retain(i8* %newValue) [[NUW]]
+; CHECK-NEXT: %x1 = load i8** @x, align 8
+; CHECK-NEXT: store i8* %x0, i8** @x, align 8
+; CHECK-NEXT: %t = icmp eq i8* %x1, %foo
+; CHECK-NEXT: tail call void @objc_release(i8* %x1) [[NUW]], !clang.imprecise_release !0
+; CHECK-NEXT: ret i1 %t
+; CHECK-NEXT: }
+define i1 @test4(i8* %newValue, i8* %foo) {
+entry:
+ %x0 = tail call i8* @objc_retain(i8* %newValue) nounwind
+ %x1 = load i8** @x, align 8
+ store i8* %newValue, i8** @x, align 8
+ %t = icmp eq i8* %x1, %foo
+ tail call void @objc_release(i8* %x1) nounwind, !clang.imprecise_release !0
+ ret i1 %t
+}
+
+; Do form an objc_storeStrong here, because the use is before the store.
+
+; CHECK: define i1 @test5(i8* %newValue, i8* %foo) {
+; CHECK: %t = icmp eq i8* %x1, %foo
+; CHECK: tail call void @objc_storeStrong(i8** @x, i8* %newValue) [[NUW]]
+; CHECK: }
+define i1 @test5(i8* %newValue, i8* %foo) {
+entry:
+ %x0 = tail call i8* @objc_retain(i8* %newValue) nounwind
+ %x1 = load i8** @x, align 8
+ %t = icmp eq i8* %x1, %foo
+ store i8* %newValue, i8** @x, align 8
+ tail call void @objc_release(i8* %x1) nounwind, !clang.imprecise_release !0
+ ret i1 %t
+}
+
+; Like test5, but the release is before the store.
+
+; CHECK: define i1 @test6(i8* %newValue, i8* %foo) {
+; CHECK: %t = icmp eq i8* %x1, %foo
+; CHECK: tail call void @objc_storeStrong(i8** @x, i8* %newValue) [[NUW]]
+; CHECK: }
+define i1 @test6(i8* %newValue, i8* %foo) {
+entry:
+ %x0 = tail call i8* @objc_retain(i8* %newValue) nounwind
+ %x1 = load i8** @x, align 8
+ tail call void @objc_release(i8* %x1) nounwind, !clang.imprecise_release !0
+ %t = icmp eq i8* %x1, %foo
+ store i8* %newValue, i8** @x, align 8
+ ret i1 %t
+}
+
+; Like test0, but there's no store, so don't form an objc_storeStrong.
+
+; CHECK-LABEL: define void @test7(
+; CHECK-NEXT: entry:
+; CHECK-NEXT: %0 = tail call i8* @objc_retain(i8* %p) [[NUW]]
+; CHECK-NEXT: %tmp = load i8** @x, align 8
+; CHECK-NEXT: tail call void @objc_release(i8* %tmp) [[NUW]]
+; CHECK-NEXT: ret void
+; CHECK-NEXT: }
+define void @test7(i8* %p) {
+entry:
+ %0 = tail call i8* @objc_retain(i8* %p) nounwind
+ %tmp = load i8** @x, align 8
+ tail call void @objc_release(i8* %tmp) nounwind
+ ret void
+}
+
+; Like test0, but there's no retain, so don't form an objc_storeStrong.
+
+; CHECK-LABEL: define void @test8(
+; CHECK-NEXT: entry:
+; CHECK-NEXT: %tmp = load i8** @x, align 8
+; CHECK-NEXT: store i8* %p, i8** @x, align 8
+; CHECK-NEXT: tail call void @objc_release(i8* %tmp) [[NUW]]
+; CHECK-NEXT: ret void
+; CHECK-NEXT: }
+define void @test8(i8* %p) {
+entry:
+ %tmp = load i8** @x, align 8
+ store i8* %p, i8** @x, align 8
+ tail call void @objc_release(i8* %tmp) nounwind
+ ret void
+}
+
+!0 = !{}
+
+; CHECK: attributes [[NUW]] = { nounwind }