This attribute, called "objc_externally_retained", exposes clang's
notion of pseudo-__strong variables in ARC. Pseudo-strong variables
"borrow" their initializer, meaning that they don't retain/release
it, instead assuming that someone else is keeping their value alive.
If a function is annotated with this attribute, implicitly strong
parameters of that function aren't implicitly retained/released in
the function body, and are implicitly const. This is useful to expose
for performance reasons, most functions don't need the extra safety
of the retain/release, so programmers can opt out as needed.
This attribute can also apply to declarations of local variables,
with similar effect.
Differential revision: https://reviews.llvm.org/D55865
llvm-svn: 350422
r348687 converted [Foo alloc] to objc_alloc(Foo). However the objc runtime method only takes a Class, not an arbitrary pointer.
This makes sure we are messaging a class before we convert these messages.
rdar://problem/46943703
llvm-svn: 350224
'\1'.
'@' can't be used in block descriptors' symbol names since it is
reserved on ELF platforms as a separator between symbol names and symbol
versions.
See the discussion here: https://reviews.llvm.org/D50783.
Differential Revision: https://reviews.llvm.org/D54539
llvm-svn: 350157
We were not emitting a protocol definition while generating the category
method list. This was fine in most cases, because something else in the
library typically referenced any given protocol, but it caused linker
failures if the category was the only reference to a given protocol.
llvm-svn: 350130
It is faster to directly call the ObjC runtime for methods such as retain/release instead of sending a message to those functions.
Differential Revision: https://reviews.llvm.org/D55869
Reviewed By: rjmccall
llvm-svn: 349952
Calls to this function are deleted in the ARC optimizer. However when the ARC
optimizer was updated to use intrinsics instead of functions (r349534), the corresponding
clang change (r349535) to use intrinsics missed this one so it wasn't being deleted.
llvm-svn: 349782
It is faster to directly call the ObjC runtime for methods such as alloc/allocWithZone instead of sending a message to those functions.
This patch adds support for converting messages to alloc/allocWithZone to their equivalent runtime calls.
Tests included for the positive case of applying this transformation, negative tests that we ensure we only convert "alloc" to objc_alloc, not "alloc2", and also a driver test to ensure we enable this only for supported runtime versions.
Reviewed By: rjmccall
https://reviews.llvm.org/D55349
llvm-svn: 348687
Function calls without a !dbg location inside a function that has a
DISubprogram make it impossible to construct inline information and
are rejected by the verifier. This patch ensures that sanitizer check
function calls have a !dbg location, by carrying forward the location
of the preceding instruction or by inserting an artificial location if
necessary.
This fixes a crash when compiling the attached testcase with -Os.
rdar://problem/45311226
Differential Revision: https://reviews.llvm.org/D53459
Note: This reapllies r344915, modified to reuse the IRBuilder's
DebugLoc if one exists instead of picking the one from CGDebugInfo
since the latter may get reset when emitting thunks such as block
helpers in the middle of emitting another function.
llvm-svn: 347810
Some ObjC users declare a extern variable named OBJC_CLASS_$_Foo, then use it's
address as a Class. I.e., one could define isInstanceOfF:
BOOL isInstanceOfF(id c) {
extern void OBJC_CLASS_$_F;
return [c class] == (Class)&OBJC_CLASS_$_F;
}
This leads to asserts in clang CodeGen if there is an @implementation of F in
the same TU as an instance of this pattern, because CodeGen assumes that a
variable named OBJC_CLASS_$_* has the right type. This commit fixes the problem
by RAUWing the old (incorrectly typed) global with a new global, then removing
the old global.
rdar://45077269
Differential revision: https://reviews.llvm.org/D53154
llvm-svn: 344373
of a non-trivial C struct, copy the preceding trivial fields that
haven't been copied.
This commit fixes a bug where the instructions used to copy the
preceding trivial fields were emitted inside the loop body.
rdar://problem/44185064
llvm-svn: 343556
from those that aren't.
This patch changes the way __block variables that aren't captured by
escaping blocks are handled:
- Since non-escaping blocks on the stack never get copied to the heap
(see https://reviews.llvm.org/D49303), Sema shouldn't error out when
the type of a non-escaping __block variable doesn't have an accessible
copy constructor.
- IRGen doesn't have to use the specialized byref structure (see
https://clang.llvm.org/docs/Block-ABI-Apple.html#id8) for a
non-escaping __block variable anymore. Instead IRGen can emit the
variable as a normal variable and copy the reference to the block
literal. Byref copy/dispose helpers aren't needed either.
This reapplies r343518 after fixing a use-after-free bug in function
Sema::ActOnBlockStmtExpr where the BlockScopeInfo was dereferenced after
it was popped and deleted.
rdar://problem/39352313
Differential Revision: https://reviews.llvm.org/D51564
llvm-svn: 343542
from those that aren't.
This patch changes the way __block variables that aren't captured by
escaping blocks are handled:
- Since non-escaping blocks on the stack never get copied to the heap
(see https://reviews.llvm.org/D49303), Sema shouldn't error out when
the type of a non-escaping __block variable doesn't have an accessible
copy constructor.
- IRGen doesn't have to use the specialized byref structure (see
https://clang.llvm.org/docs/Block-ABI-Apple.html#id8) for a
non-escaping __block variable anymore. Instead IRGen can emit the
variable as a normal variable and copy the reference to the block
literal. Byref copy/dispose helpers aren't needed either.
This reapplies r341754, which was reverted in r341757 because it broke a
couple of bots. r341754 was calling markEscapingByrefs after the call to
PopFunctionScopeInfo, which caused the popped function scope to be
cleared out when the following code was compiled, for example:
$ cat test.m
struct A {
id data[10];
};
void foo() {
__block A v;
^{ (void)v; };
}
This commit calls markEscapingByrefs before calling PopFunctionScopeInfo
to prevent that from happening.
rdar://problem/39352313
Differential Revision: https://reviews.llvm.org/D51564
llvm-svn: 343518
Summary:
Some lines have a hit counter where they should not have one.
Cleanup stuff is located to the last line of the body which is most of the time a '}'.
And Exception stuff is added at the beginning of a function and at the end (represented by '{' and '}').
So in such cases, the DebugLoc used in GCOVProfiling.cpp must be marked as not covered.
This patch is a followup of https://reviews.llvm.org/D49915.
Tests in projects/compiler_rt are fixed by: https://reviews.llvm.org/D49917
Reviewers: marco-c, davidxl
Reviewed By: marco-c
Subscribers: dblaikie, cfe-commits, sylvestre.ledru
Differential Revision: https://reviews.llvm.org/D49916
llvm-svn: 342717
This patch removes the last reason why DIFlagBlockByrefStruct from
Clang by directly implementing the drilling into the member type done
in DwarfDebug::DbgVariable::getType() into the frontend.
rdar://problem/31629055
Differential Revision: https://reviews.llvm.org/D51807
llvm-svn: 341842
from those that aren't.
This patch changes the way __block variables that aren't captured by
escaping blocks are handled:
- Since non-escaping blocks on the stack never get copied to the heap
(see https://reviews.llvm.org/D49303), Sema shouldn't error out when
the type of a non-escaping __block variable doesn't have an accessible
copy constructor.
- IRGen doesn't have to use the specialized byref structure (see
https://clang.llvm.org/docs/Block-ABI-Apple.html#id8) for a
non-escaping __block variable anymore. Instead IRGen can emit the
variable as a normal variable and copy the reference to the block
literal. Byref copy/dispose helpers aren't needed either.
rdar://problem/39352313
Differential Revision: https://reviews.llvm.org/D51564
llvm-svn: 341754
expression
Clang emits invalid protocol metadata when a @protocol expression is used with a
forward-declared protocol. The protocol metadata is missing protocol conformance
list of the protocol since we don't have access to the definition of it in the
compiled translation unit. The linker then might end up picking the invalid
metadata when linking which will lead to incorrect runtime protocol conformance
checks.
This commit makes sure that Clang fails to compile code that uses a @protocol
expression with a forward-declared protocol. This ensures that Clang does not
emit invalid protocol metadata. I added an extra assert in CodeGen to ensure
that this kind of issue won't happen in other places.
rdar://32787811
Differential Revision: https://reviews.llvm.org/D49462
llvm-svn: 340102
Currently, clang generates a new block descriptor global variable for
each new block literal. This commit merges block descriptors that are
identical inside and across translation units using the same approach
taken in r339438.
To enable merging identical block descriptors, the size and signature of
the block and information about the captures are encoded into the name
of the block descriptor variable. Also, the block descriptor variable is
marked as linkonce_odr and unnamed_addr.
rdar://problem/42640703
Differential Revision: https://reviews.llvm.org/D50783
llvm-svn: 340041
Summary:
This probably fixes PR35277, though there may be other sources of
nondeterminism (this was the only case of iterating over a DenseMap).
It's difficult to provide a test case for this, because it shows up only
on systems with ASLR enabled.
Reviewers: rjmccall
Reviewed By: rjmccall
Subscribers: bmwiedemann, mgrang, cfe-commits
Differential Revision: https://reviews.llvm.org/D50559
llvm-svn: 339668
Clang generates copy and dispose helper functions for each block literal
on the stack. Often these functions are equivalent for different blocks.
This commit makes changes to merge equivalent copy and dispose helper
functions and reduce code size.
To enable merging equivalent copy/dispose functions, the captured object
infomation is encoded into the helper function name. This allows IRGen
to check whether an equivalent helper function has already been emitted
and reuse the function instead of generating a new helper function
whenever a block is defined. In addition, the helper functions are
marked as linkonce_odr to enable merging helper functions that have the
same name across translation units and marked as unnamed_addr to enable
the linker's deduplication pass to merge functions that have different
names but the same content.
rdar://problem/42640608
Differential Revision: https://reviews.llvm.org/D50152
llvm-svn: 339438
Summary:
Introduces funclet-based unwinding for Objective-C and fixes an issue
where global blocks can't have their isa pointers initialised on
Windows.
After discussion with Dustin, this changes the name mangling of
Objective-C types to prevent a C++ catch statement of type struct X*
from catching an Objective-C object of type X*.
Reviewers: rjmccall, DHowett-MSFT
Reviewed By: rjmccall, DHowett-MSFT
Subscribers: mgrang, mstorsjo, smeenai, cfe-commits
Differential Revision: https://reviews.llvm.org/D50144
llvm-svn: 339428
When an exception is thrown in a block copy helper function, captured
objects that have previously been copied should be destructed or
released. Similarly, captured objects that are yet to be released should
be released when an exception is thrown in a dispose helper function.
rdar://problem/42410255
Differential Revision: https://reviews.llvm.org/D49718
llvm-svn: 338041
no-ops.
A non-escaping block on the stack will never be called after its
lifetime ends, so it doesn't have to be copied to the heap. To prevent
a non-escaping block from being copied to the heap, this patch sets
field 'isa' of the block object to NSConcreteGlobalBlock and sets the
BLOCK_IS_GLOBAL bit of field 'flags', which causes the runtime to treat
the block as if it were a global block (calling _Block_copy on the block
just returns the original block and calling _Block_release is a no-op).
Also, a new flag bit 'BLOCK_IS_NOESCAPE' is added, which allows the
runtime or tools to distinguish between true global blocks and
non-escaping blocks.
rdar://problem/39352313
Differential Revision: https://reviews.llvm.org/D49303
llvm-svn: 337580
As brought up during the discussion of the DWARF5 accelerator tables,
there is currently no way to associate Objective-C methods with the
interface they belong to, other than the .apple_objc accelerator table.
After due consideration we came to the conclusion that it makes more
sense to follow Pavel's suggestion of just emitting this information in
the .debug_info section. One concern was that categories were
emitted in the .apple_names as well, but it turns out that LLDB doesn't
rely on the accelerator tables for this information.
This patch changes the codegen behavior to emit subprograms for
structure types, like we do for C++. This will result in the
DW_TAG_subprogram being nested as a child under its
DW_TAG_structure_type. This behavior is only enabled for DWARF5 and
later, so we can have a unique code path in LLDB with regards to
obtaining the class methods.
This was tested on the LLDB side and doesn't lead to a regression.
There's already code in place to deal with member functions in C++,
which deals with this transparently.
For more background please refer to the discussion on the mailing list:
http://lists.llvm.org/pipermail/llvm-dev/2018-June/123986.html
Differential revision: https://reviews.llvm.org/D48241
llvm-svn: 335757
When the return type of an ObjC-style block literals is deduced, pick
the candidate type with the strictest nullability annotation applicable
to every other candidate.
This suppresses a UBSan false-positive in situations where a too-strict
nullability would be deduced, despite the fact that the returned value
would be implicitly cast to _Nullable.
rdar://41317163
llvm-svn: 335572
The windows-msvc target is meant to be ABI compatible with MSVC,
including the exception handling. Ensure that a windows-msvc triple
always equates to the MSVC personality being used.
This mostly affects the GNUStep and ObjFW Obj-C runtimes. To the best of
my knowledge, those are normally not used with windows-msvc triples. I
believe WinObjC is based on GNUStep (or it at least uses libobjc2), but
that also takes the approach of wrapping Obj-C exceptions in C++
exceptions, so the MSVC personality function is the right one to use
there as well.
Differential Revision: https://reviews.llvm.org/D47862
llvm-svn: 334253
The windows-msvc target is used for MSVC ABI compatibility, including
the exceptions model. It doesn't make sense to pair a windows-msvc
target with a non-MSVC exception model. This would previously cause an
assertion failure; explicitly error out for it in the frontend instead.
This also allows us to reduce the matrix of target/exception models a
bit (see the modified tests), and we can possibly simplify some of the
personality code in a follow-up.
Differential Revision: https://reviews.llvm.org/D47853
llvm-svn: 334243
Summary:
This includes initial support for the (hopefully final) updated Objective-C ABI, developed here:
https://github.com/davidchisnall/clang-gnustep-abi-2
It also includes some cleanups and refactoring from older GNU ABIs.
The current version is ELF only, other formats to follow.
Reviewers: rjmccall, DHowett-MSFT
Reviewed By: rjmccall
Subscribers: smeenai, cfe-commits
Differential Revision: https://reviews.llvm.org/D46052
llvm-svn: 332950
objc_begin_catch/objc_end_catch are specific to the Itanium ABI, so we
should be using an Itanium triple for this test.
Additionally, while I'm here, convert the run line to invoke the
compiler directly rather than going through the driver.
llvm-svn: 332777
volatile array field is copied.
The crash occurs because method 'visitArray' passes a null FieldDecl to
method 'visit' and some of the methods called downstream expect a
non-null FieldDecl to be passed.
This reapplies r330151 with a fix to the test case.
rdar://problem/33599681
llvm-svn: 330155
volatile array field is copied.
The crash occurs because method 'visitArray' passes a null FieldDecl to
method 'visit' and some of the methods called downstream expect a
non-null FieldDecl to be passed.
rdar://problem/33599681
llvm-svn: 330151
Summary:
Protocols that were being referenced but could not be fully realized were being emitted without `properties`/`optional_properties`. Since all v3 protocols must be 9 processor words wide, the lack of these fields is catastrophic for the runtime.
As an example, the runtime cannot know [here](https://github.com/gnustep/libobjc2/blob/master/protocol.c#L73) that `properties` and `optional_properties` are invalid.
Reviewers: rjmccall, theraven
Reviewed By: rjmccall, theraven
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D45305
llvm-svn: 329882
identifier.
This patch fixes a few places in CGObjCMac.cpp where the class
identifier was used instead of the name specified by objc_runtime_name.
rdar://problem/37910822
Differential Revision: https://reviews.llvm.org/D45101
llvm-svn: 329128
This commit generalizes NRVO to cover C structs (both trivial and
non-trivial structs).
rdar://problem/33599681
Differential Revision: https://reviews.llvm.org/D44968
llvm-svn: 328809
source expressions when iterating over a PseudoObjectExpr's semantic
subexpression list.
Previously the loop in emitPseudoObjectExpr would emit the IR for each
OpaqueValueExpr that was in a PseudoObjectExpr's semantic-form
expression list and use the result when the OpaqueValueExpr later
appeared in other expressions. This caused an assertion failure when
AggExprEmitter tried to copy the result of an OpaqueValueExpr and the
copied type didn't have trivial copy/move constructors or assignment
operators.
This patch adds flag IsUnique to OpaqueValueExpr which indicates it is a
unique reference to its source expression (it is not used in multiple
places). The loop in emitPseudoObjectExpr ignores OpaqueValueExprs that
are unique and CodeGen visitors simply traverse the source expressions
of such OpaqueValueExprs.
rdar://problem/34363596
Differential Revision: https://reviews.llvm.org/D39562
llvm-svn: 327939
This patch uses the infrastructure added in r326307 for enabling
non-trivial fields to be declared in C structs to allow __weak fields in
C structs in ARC.
This recommits r327206, which was reverted because it caused
module-enabled builders to fail. I discovered that the
CXXRecordDecl::CanPassInRegisters flag wasn't being set correctly in
some cases after I moved it to RecordDecl.
Thanks to Eric Liu for helping me investigate the bug.
rdar://problem/33599681
https://reviews.llvm.org/D44095
llvm-svn: 327870
setting the NonTrivialToPrimitive* flags of a record.
Union fields that have non-trivial Objective-C ownership qualifications
are normally not legal, but if the union is declared in a system header,
the fields are annotated with attribute "unavailable".
rdar://problem/38431072
llvm-svn: 327464