6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-12-15 20:29:48 +00:00
Code Issues Projects Releases Wiki Activity
35e88e57ea
llvm-6502/test/Transforms/ObjCARC/allocas.ll

301 lines
7.5 KiB
LLVM
Raw Normal View History

[objc-arc-opts] In the presense of an alloca unconditionally remove RR pairs if and only if we are both KnownSafeBU/KnownSafeTD rather than just either or. In the presense of a block being initialized, the frontend will emit the objc_retain on the original pointer and the release on the pointer loaded from the alloca. The optimizer will through the provenance analysis realize that the two are related (albiet different), but since we only require KnownSafe in one direction, will match the inner retain on the original pointer with the guard release on the original pointer. This is fixed by ensuring that in the presense of allocas we only unconditionally remove pointers if both our retain and our release are KnownSafe (i.e. we are KnownSafe in both directions) since we must deal with the possibility that the frontend will emit what (to the optimizer) appears to be unbalanced retain/releases. An example of the miscompile is: %A = alloca retain(%x) retain(%x) <--- Inner Retain store %x, %A %y = load %A ... DO STUFF ... release(%y) call void @use(%x) release(%x) <--- Guarding Release getting optimized to: %A = alloca retain(%x) store %x, %A %y = load %A ... DO STUFF ... release(%y) call void @use(%x) rdar://13750319 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181743 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-13 23:49:42 +00:00
; RUN: opt -objc-arc -S < %s | FileCheck %s
declare i8* @objc_retain(i8*)
declare i8* @objc_retainAutoreleasedReturnValue(i8*)
declare void @objc_release(i8*)
declare i8* @objc_autorelease(i8*)
declare i8* @objc_autoreleaseReturnValue(i8*)
declare void @objc_autoreleasePoolPop(i8*)
declare i8* @objc_autoreleasePoolPush()
declare i8* @objc_retainBlock(i8*)
declare i8* @objc_retainedObject(i8*)
declare i8* @objc_unretainedObject(i8*)
declare i8* @objc_unretainedPointer(i8*)
declare void @use_pointer(i8*)
declare void @callee()
declare void @callee_fnptr(void ()*)
declare void @invokee()
declare i8* @returner()
declare void @bar(i32 ()*)
declare void @use_alloca(i8**)
declare void @llvm.dbg.value(metadata, i64, metadata)
declare i8* @objc_msgSend(i8*, i8*, ...)
; In the presense of allocas, unconditionally remove retain/release pairs only
; if they are known safe in both directions. This prevents matching up an inner
; retain with the boundary guarding release in the following situation:
;
; %A = alloca
; retain(%x)
; retain(%x) <--- Inner Retain
; store %x, %A
; %y = load %A
; ... DO STUFF ...
; release(%y)
; release(%x) <--- Guarding Release
;
; rdar://13750319
; CHECK: define void @test1a(i8* %x)
; CHECK: @objc_retain(i8* %x)
; CHECK: @objc_retain(i8* %x)
; CHECK: @objc_release(i8* %y)
; CHECK: @objc_release(i8* %x)
; CHECK: ret void
; CHECK: }
define void @test1a(i8* %x) {
entry:
%A = alloca i8*
tail call i8* @objc_retain(i8* %x)
tail call i8* @objc_retain(i8* %x)
store i8* %x, i8** %A, align 8
%y = load i8** %A
call void @use_alloca(i8** %A)
call void @objc_release(i8* %y), !clang.imprecise_release !0
call void @use_pointer(i8* %x)
call void @objc_release(i8* %x), !clang.imprecise_release !0
ret void
}
; CHECK: define void @test1b(i8* %x)
; CHECK: @objc_retain(i8* %x)
; CHECK: @objc_retain(i8* %x)
; CHECK: @objc_release(i8* %y)
; CHECK: @objc_release(i8* %x)
; CHECK: ret void
; CHECK: }
define void @test1b(i8* %x) {
entry:
%A = alloca i8*
%gep = getelementptr i8** %A, i32 0
tail call i8* @objc_retain(i8* %x)
tail call i8* @objc_retain(i8* %x)
store i8* %x, i8** %gep, align 8
%y = load i8** %A
call void @use_alloca(i8** %A)
call void @objc_release(i8* %y), !clang.imprecise_release !0
call void @use_pointer(i8* %x)
call void @objc_release(i8* %x), !clang.imprecise_release !0
ret void
}
; CHECK: define void @test1c(i8* %x)
; CHECK: @objc_retain(i8* %x)
; CHECK: @objc_retain(i8* %x)
; CHECK: @objc_release(i8* %y)
; CHECK: @objc_release(i8* %x)
; CHECK: ret void
; CHECK: }
define void @test1c(i8* %x) {
entry:
%A = alloca i8*, i32 3
%gep = getelementptr i8** %A, i32 2
tail call i8* @objc_retain(i8* %x)
tail call i8* @objc_retain(i8* %x)
store i8* %x, i8** %gep, align 8
%y = load i8** %gep
call void @use_alloca(i8** %A)
call void @objc_release(i8* %y), !clang.imprecise_release !0
call void @use_pointer(i8* %x)
call void @objc_release(i8* %x), !clang.imprecise_release !0
ret void
}
; CHECK: define void @test1d(i8* %x)
; CHECK: @objc_retain(i8* %x)
; CHECK: @objc_retain(i8* %x)
; CHECK: @objc_release(i8* %y)
; CHECK: @objc_release(i8* %x)
; CHECK: ret void
; CHECK: }
define void @test1d(i8* %x) {
entry:
br i1 undef, label %use_allocaA, label %use_allocaB
use_allocaA:
%allocaA = alloca i8*
br label %exit
use_allocaB:
%allocaB = alloca i8*
br label %exit
exit:
%A = phi i8** [ %allocaA, %use_allocaA ], [ %allocaB, %use_allocaB ]
%gep = getelementptr i8** %A, i32 0
tail call i8* @objc_retain(i8* %x)
tail call i8* @objc_retain(i8* %x)
store i8* %x, i8** %gep, align 8
%y = load i8** %gep
call void @use_alloca(i8** %A)
call void @objc_release(i8* %y), !clang.imprecise_release !0
call void @use_pointer(i8* %x)
call void @objc_release(i8* %x), !clang.imprecise_release !0
ret void
}
; CHECK: define void @test1e(i8* %x)
; CHECK: @objc_retain(i8* %x)
; CHECK: @objc_retain(i8* %x)
; CHECK: @objc_release(i8* %y)
; CHECK: @objc_release(i8* %x)
; CHECK: ret void
; CHECK: }
define void @test1e(i8* %x) {
entry:
br i1 undef, label %use_allocaA, label %use_allocaB
use_allocaA:
%allocaA = alloca i8*, i32 4
br label %exit
use_allocaB:
%allocaB = alloca i8*, i32 4
br label %exit
exit:
%A = phi i8** [ %allocaA, %use_allocaA ], [ %allocaB, %use_allocaB ]
%gep = getelementptr i8** %A, i32 2
tail call i8* @objc_retain(i8* %x)
tail call i8* @objc_retain(i8* %x)
store i8* %x, i8** %gep, align 8
%y = load i8** %gep
call void @use_alloca(i8** %A)
call void @objc_release(i8* %y), !clang.imprecise_release !0
call void @use_pointer(i8* %x)
call void @objc_release(i8* %x), !clang.imprecise_release !0
ret void
}
; CHECK: define void @test1f(i8* %x)
; CHECK: @objc_retain(i8* %x)
; CHECK: @objc_retain(i8* %x)
; CHECK: @objc_release(i8* %y)
; CHECK: @objc_release(i8* %x)
; CHECK: ret void
; CHECK: }
define void @test1f(i8* %x) {
entry:
%allocaOne = alloca i8*
%allocaTwo = alloca i8*
%A = select i1 undef, i8** %allocaOne, i8** %allocaTwo
tail call i8* @objc_retain(i8* %x)
tail call i8* @objc_retain(i8* %x)
store i8* %x, i8** %A, align 8
%y = load i8** %A
call void @use_alloca(i8** %A)
call void @objc_release(i8* %y), !clang.imprecise_release !0
call void @use_pointer(i8* %x)
call void @objc_release(i8* %x), !clang.imprecise_release !0
ret void
}
[objc-arc] Make sure that multiple owners is propogated correctly through the pass via the usage of a global data structure. rdar://13750319 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182669 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-24 20:44:02 +00:00
; Make sure that if a store is in a different basic block we handle known safe
; conservatively.
; CHECK: define void @test2a(i8* %x)
; CHECK: @objc_retain(i8* %x)
; CHECK: @objc_retain(i8* %x)
; CHECK: @objc_release(i8* %y)
; CHECK: @objc_release(i8* %x)
; CHECK: ret void
; CHECK: }
define void @test2a(i8* %x) {
entry:
%A = alloca i8*
store i8* %x, i8** %A, align 8
%y = load i8** %A
br label %bb1
bb1:
br label %bb2
bb2:
br label %bb3
bb3:
tail call i8* @objc_retain(i8* %x)
tail call i8* @objc_retain(i8* %x)
call void @use_alloca(i8** %A)
call void @objc_release(i8* %y), !clang.imprecise_release !0
call void @use_pointer(i8* %x)
call void @objc_release(i8* %x), !clang.imprecise_release !0
ret void
}
; CHECK: define void @test2b(i8* %x)
; CHECK: @objc_retain(i8* %x)
; CHECK: @objc_retain(i8* %x)
; CHECK: @objc_release(i8* %y)
; CHECK: @objc_release(i8* %x)
; CHECK: ret void
; CHECK: }
define void @test2b(i8* %x) {
entry:
%A = alloca i8*
%gep1 = getelementptr i8** %A, i32 0
store i8* %x, i8** %gep1, align 8
%gep2 = getelementptr i8** %A, i32 0
%y = load i8** %gep2
br label %bb1
bb1:
br label %bb2
bb2:
br label %bb3
bb3:
tail call i8* @objc_retain(i8* %x)
tail call i8* @objc_retain(i8* %x)
call void @use_alloca(i8** %A)
call void @objc_release(i8* %y), !clang.imprecise_release !0
call void @use_pointer(i8* %x)
call void @objc_release(i8* %x), !clang.imprecise_release !0
ret void
}
; CHECK: define void @test2c(i8* %x)
; CHECK: @objc_retain(i8* %x)
; CHECK: @objc_retain(i8* %x)
; CHECK: @objc_release(i8* %y)
; CHECK: @objc_release(i8* %x)
; CHECK: ret void
; CHECK: }
define void @test2c(i8* %x) {
entry:
%A = alloca i8*, i32 3
%gep1 = getelementptr i8** %A, i32 2
store i8* %x, i8** %gep1, align 8
%gep2 = getelementptr i8** %A, i32 2
%y = load i8** %gep2
tail call i8* @objc_retain(i8* %x)
br label %bb1
bb1:
br label %bb2
bb2:
br label %bb3
bb3:
tail call i8* @objc_retain(i8* %x)
call void @use_alloca(i8** %A)
call void @objc_release(i8* %y), !clang.imprecise_release !0
call void @use_pointer(i8* %x)
call void @objc_release(i8* %x), !clang.imprecise_release !0
ret void
}
[objc-arc-opts] In the presense of an alloca unconditionally remove RR pairs if and only if we are both KnownSafeBU/KnownSafeTD rather than just either or. In the presense of a block being initialized, the frontend will emit the objc_retain on the original pointer and the release on the pointer loaded from the alloca. The optimizer will through the provenance analysis realize that the two are related (albiet different), but since we only require KnownSafe in one direction, will match the inner retain on the original pointer with the guard release on the original pointer. This is fixed by ensuring that in the presense of allocas we only unconditionally remove pointers if both our retain and our release are KnownSafe (i.e. we are KnownSafe in both directions) since we must deal with the possibility that the frontend will emit what (to the optimizer) appears to be unbalanced retain/releases. An example of the miscompile is: %A = alloca retain(%x) retain(%x) <--- Inner Retain store %x, %A %y = load %A ... DO STUFF ... release(%y) call void @use(%x) release(%x) <--- Guarding Release getting optimized to: %A = alloca retain(%x) store %x, %A %y = load %A ... DO STUFF ... release(%y) call void @use(%x) rdar://13750319 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@181743 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-13 23:49:42 +00:00
!0 = metadata !{}
declare i32 @__gxx_personality_v0(...)
Reference in New Issue Copy Permalink