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|
; RUN: opt -objc-arc-contract -S < %s | FileCheck %s
target datalayout = "e-p:64:64:64"
declare i8* @llvm.objc.retain(i8*)
declare void @llvm.objc.release(i8*)
declare void @use_pointer(i8*)
@x = external global i8*
; CHECK-LABEL: define void @test0(
; CHECK: entry:
; CHECK-NEXT: tail call void @llvm.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* @llvm.objc.retain(i8* %p) nounwind
%tmp = load i8*, i8** @x, align 8
store i8* %0, i8** @x, align 8
tail call void @llvm.objc.release(i8* %tmp) nounwind
ret void
}
; Don't do this if the load is volatile.
; CHECK-LABEL: define void @test1(i8* %p) {
; CHECK-NEXT: entry:
; CHECK-NEXT: %0 = tail call i8* @llvm.objc.retain(i8* %p) [[NUW]]
; CHECK-NEXT: %tmp = load volatile i8*, i8** @x, align 8
; CHECK-NEXT: store i8* %0, i8** @x, align 8
; CHECK-NEXT: tail call void @llvm.objc.release(i8* %tmp) [[NUW]]
; CHECK-NEXT: ret void
; CHECK-NEXT: }
define void @test1(i8* %p) {
entry:
%0 = tail call i8* @llvm.objc.retain(i8* %p) nounwind
%tmp = load volatile i8*, i8** @x, align 8
store i8* %0, i8** @x, align 8
tail call void @llvm.objc.release(i8* %tmp) nounwind
ret void
}
; Don't do this if the store is volatile.
; CHECK-LABEL: define void @test2(i8* %p) {
; CHECK-NEXT: entry:
; CHECK-NEXT: %0 = tail call i8* @llvm.objc.retain(i8* %p) [[NUW]]
; CHECK-NEXT: %tmp = load i8*, i8** @x, align 8
; CHECK-NEXT: store volatile i8* %0, i8** @x, align 8
; CHECK-NEXT: tail call void @llvm.objc.release(i8* %tmp) [[NUW]]
; CHECK-NEXT: ret void
; CHECK-NEXT: }
define void @test2(i8* %p) {
entry:
%0 = tail call i8* @llvm.objc.retain(i8* %p) nounwind
%tmp = load i8*, i8** @x, align 8
store volatile i8* %0, i8** @x, align 8
tail call void @llvm.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-LABEL: define void @test3(i8* %newValue) {
; CHECK-NEXT: entry:
; CHECK-NEXT: %x0 = tail call i8* @llvm.objc.retain(i8* %newValue) [[NUW]]
; CHECK-NEXT: %x1 = load i8*, 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 @llvm.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* @llvm.objc.retain(i8* %newValue) nounwind
%x1 = load i8*, 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 @llvm.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-LABEL: define i1 @test4(i8* %newValue, i8* %foo) {
; CHECK-NEXT: entry:
; CHECK-NEXT: %x0 = tail call i8* @llvm.objc.retain(i8* %newValue) [[NUW]]
; CHECK-NEXT: %x1 = load i8*, 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 @llvm.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* @llvm.objc.retain(i8* %newValue) nounwind
%x1 = load i8*, i8** @x, align 8
store i8* %newValue, i8** @x, align 8
%t = icmp eq i8* %x1, %foo
tail call void @llvm.objc.release(i8* %x1) nounwind, !clang.imprecise_release !0
ret i1 %t
}
; Do form an llvm.objc.storeStrong here, because the use is before the store.
; CHECK-LABEL: define i1 @test5(i8* %newValue, i8* %foo) {
; CHECK: %t = icmp eq i8* %x1, %foo
; CHECK: tail call void @llvm.objc.storeStrong(i8** @x, i8* %newValue) [[NUW]]
; CHECK: }
define i1 @test5(i8* %newValue, i8* %foo) {
entry:
%x0 = tail call i8* @llvm.objc.retain(i8* %newValue) nounwind
%x1 = load i8*, i8** @x, align 8
%t = icmp eq i8* %x1, %foo
store i8* %newValue, i8** @x, align 8
tail call void @llvm.objc.release(i8* %x1) nounwind, !clang.imprecise_release !0
ret i1 %t
}
; Like test5, but the release is before the store.
; CHECK-LABEL: define i1 @test6(i8* %newValue, i8* %foo) {
; CHECK: %t = icmp eq i8* %x1, %foo
; CHECK: tail call void @llvm.objc.storeStrong(i8** @x, i8* %newValue) [[NUW]]
; CHECK: }
define i1 @test6(i8* %newValue, i8* %foo) {
entry:
%x0 = tail call i8* @llvm.objc.retain(i8* %newValue) nounwind
%x1 = load i8*, i8** @x, align 8
tail call void @llvm.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 llvm.objc.storeStrong.
; CHECK-LABEL: define void @test7(
; CHECK-NEXT: entry:
; CHECK-NEXT: %0 = tail call i8* @llvm.objc.retain(i8* %p) [[NUW]]
; CHECK-NEXT: %tmp = load i8*, i8** @x, align 8
; CHECK-NEXT: tail call void @llvm.objc.release(i8* %tmp) [[NUW]]
; CHECK-NEXT: ret void
; CHECK-NEXT: }
define void @test7(i8* %p) {
entry:
%0 = tail call i8* @llvm.objc.retain(i8* %p) nounwind
%tmp = load i8*, i8** @x, align 8
tail call void @llvm.objc.release(i8* %tmp) nounwind
ret void
}
; Like test0, but there's no retain, so don't form an llvm.objc.storeStrong.
; CHECK-LABEL: define void @test8(
; CHECK-NEXT: entry:
; CHECK-NEXT: %tmp = load i8*, i8** @x, align 8
; CHECK-NEXT: store i8* %p, i8** @x, align 8
; CHECK-NEXT: tail call void @llvm.objc.release(i8* %tmp) [[NUW]]
; CHECK-NEXT: ret void
; CHECK-NEXT: }
define void @test8(i8* %p) {
entry:
%tmp = load i8*, i8** @x, align 8
store i8* %p, i8** @x, align 8
tail call void @llvm.objc.release(i8* %tmp) nounwind
ret void
}
; Make sure that we properly handle release that *may* release our new
; value in between the retain and the store. We need to be sure that
; this we can safely move the retain to the store. This specific test
; makes sure that we properly handled a release of an unrelated
; pointer.
;
; CHECK-LABEL: define i1 @test9(i8* %newValue, i8* %foo, i8* %unrelated_ptr) {
; CHECK-NOT: llvm.objc.storeStrong
define i1 @test9(i8* %newValue, i8* %foo, i8* %unrelated_ptr) {
entry:
%x0 = tail call i8* @llvm.objc.retain(i8* %newValue) nounwind
tail call void @llvm.objc.release(i8* %unrelated_ptr) nounwind, !clang.imprecise_release !0
%x1 = load i8*, i8** @x, align 8
tail call void @llvm.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
}
; Make sure that we don't perform the optimization when we just have a call.
;
; CHECK-LABEL: define i1 @test10(i8* %newValue, i8* %foo, i8* %unrelated_ptr) {
; CHECK-NOT: llvm.objc.storeStrong
define i1 @test10(i8* %newValue, i8* %foo, i8* %unrelated_ptr) {
entry:
%x0 = tail call i8* @llvm.objc.retain(i8* %newValue) nounwind
call void @use_pointer(i8* %unrelated_ptr)
%x1 = load i8*, i8** @x, align 8
tail call void @llvm.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
}
; Make sure we form the store strong if the use in between the retain
; and the store does not touch reference counts.
; CHECK-LABEL: define i1 @test11(i8* %newValue, i8* %foo, i8* %unrelated_ptr) {
; CHECK: llvm.objc.storeStrong
define i1 @test11(i8* %newValue, i8* %foo, i8* %unrelated_ptr) {
entry:
%x0 = tail call i8* @llvm.objc.retain(i8* %newValue) nounwind
%t = icmp eq i8* %newValue, %foo
%x1 = load i8*, i8** @x, align 8
tail call void @llvm.objc.release(i8* %x1) nounwind, !clang.imprecise_release !0
store i8* %newValue, i8** @x, align 8
ret i1 %t
}
; Make sure that we form the store strong even if there are bitcasts on
; the pointers.
; CHECK-LABEL: define void @test12(
; CHECK: entry:
; CHECK-NEXT: %p16 = bitcast i8** @x to i16**
; CHECK-NEXT: %tmp16 = load i16*, i16** %p16, align 8
; CHECK-NEXT: %tmp8 = bitcast i16* %tmp16 to i8*
; CHECK-NEXT: %p32 = bitcast i8** @x to i32**
; CHECK-NEXT: %v32 = bitcast i8* %p to i32*
; CHECK-NEXT: %0 = bitcast i16** %p16 to i8**
; CHECK-NEXT: tail call void @llvm.objc.storeStrong(i8** %0, i8* %p)
; CHECK-NEXT: ret void
; CHECK-NEXT: }
define void @test12(i8* %p) {
entry:
%retain = tail call i8* @llvm.objc.retain(i8* %p) nounwind
%p16 = bitcast i8** @x to i16**
%tmp16 = load i16*, i16** %p16, align 8
%tmp8 = bitcast i16* %tmp16 to i8*
%p32 = bitcast i8** @x to i32**
%v32 = bitcast i8* %retain to i32*
store i32* %v32, i32** %p32, align 8
tail call void @llvm.objc.release(i8* %tmp8) nounwind
ret void
}
; This used to crash.
; CHECK-LABEL: define i8* @test13(
; CHECK: tail call void @llvm.objc.storeStrong(i8** %{{.*}}, i8* %[[NEW:.*]])
; CHECK-NEXT: ret i8* %[[NEW]]
define i8* @test13(i8* %a0, i8* %a1, i8** %addr, i8* %new) {
%old = load i8*, i8** %addr, align 8
call void @llvm.objc.release(i8* %old)
%retained = call i8* @llvm.objc.retain(i8* %new)
store i8* %retained, i8** %addr, align 8
ret i8* %retained
}
; Cannot form a storeStrong call because it's unsafe to move the release call to
; the store.
; CHECK-LABEL: define void @test14(
; CHECK: %[[V0:.*]] = load i8*, i8** %a
; CHECK: %[[V1:.*]] = call i8* @llvm.objc.retain(i8* %p)
; CHECK: store i8* %[[V1]], i8** %a
; CHECK: %[[V2:.*]] = call i8* @llvm.objc.retain(i8* %[[V0]])
; CHECK: call void @llvm.objc.release(i8* %[[V2]])
define void @test14(i8** %a, i8* %p) {
%v0 = load i8*, i8** %a, align 8
%v1 = call i8* @llvm.objc.retain(i8* %p)
store i8* %p, i8** %a, align 8
%v2 = call i8* @llvm.objc.retain(i8* %v0)
call void @llvm.objc.release(i8* %v0)
ret void
}
!0 = !{}
; CHECK: attributes [[NUW]] = { nounwind }
|
