This patch fixes problems that pop up when clang emits DbgRecords
instead of debug intrinsics.
Note: this doesn't mean clang is emitting DbgRecords yet, because the
modules it creates are still always in the old debug mode. That will
come in a future patch.
Depends on #84739
This patch fixes problems that pop up when clang emits DbgRecords
instead of debug intrinsics.
Note: this doesn't mean clang is emitting DbgRecords yet, because the
modules it creates are still always in the old debug mode. That will
come in a future patch.
Depends on #84739
As of now, we only check if a class directly inherits from NSObject to
determine if said class has fixed offsets and can therefore "opt-out"
from the non-fragile ABI for ivars.
However, if an NSObject subclass has fixed offsets, then so must the
subclasses of that subclass, so this allows us to optimize instances of
subclasses of subclasses that inherit from NSObject and so on.
To determine this, we need to find that the compiler can see the
implementation of each intermediate class, as that means it is
statically linked.
Fixes: #81369
This patch canonicalizes getelementptr instructions with constant
indices to use the `i8` source element type. This makes it easier for
optimizations to recognize that two GEPs are identical, because they
don't need to see past many different ways to express the same offset.
This is a first step towards
https://discourse.llvm.org/t/rfc-replacing-getelementptr-with-ptradd/68699.
This is limited to constant GEPs only for now, as they have a clear
canonical form, while we're not yet sure how exactly to deal with
variable indices.
The test llvm/test/Transforms/PhaseOrdering/switch_with_geps.ll gives
two representative examples of the kind of optimization improvement we
expect from this change. In the first test SimplifyCFG can now realize
that all switch branches are actually the same. In the second test it
can convert it into simple arithmetic. These are representative of
common optimization failures we see in Rust.
Fixes https://github.com/llvm/llvm-project/issues/69841.
These will be supported in the upcoming 2.2 release and so are gated on
that version.
Direct methods call `objc_send_initialize` if they are class methods
that may not have called initialize. This is guarded by checking for the
class flag bit that is set on initialisation in the class. This bit now
forms part of the ABI, but it's been stable for 30+ years so that's fine
as a contract going forwards.
Type encodings are part of symbol names in the Objective C ABI. Replace
characters which are reseved in symbol names:
- ELF: avoid including '@' characters in type encodings
- Windows: avoid including '=' characters in type encodings
Set the writable and dead_on_unwind attributes for sret arguments. These
indicate that the argument points to writable memory (and it's legal to
introduce spurious writes to it on entry to the function) and that the
argument memory will not be used if the call unwinds.
This enables additional MemCpyOpt/DSE/LICM optimizations.
The GNUstep Objective C runtime (libobjc2) is adding support for the GNU
ABI on Windows (more specifically, MinGW). The libobjc2 runtime uses C++
exceptions in that configuration; this PR updates clang to act
accordingly.
The corresponding change to libobjc2 is here:
https://github.com/gnustep/libobjc2/pull/267
Mark instance variable offset symbols with `dllexport`/`dllimport` if
they are not hidden and the interface declaration is marked with
`dllexport`/`dllimport`, when using the GNUstep 2.x ABI.
/cc @davidchisnall
* Mark SVE ACLE types as substitution candidates.
* Change mangling of svbfloat16_t from __SVBFloat16_t to
__SVBfloat16_t.
https://github.com/ARM-software/abi-aa/blob/main/aapcs64/aapcs64.rst
This is an ABI break with the old behaviour available via
"-fclang-abi-compat=17".
Add a new attribute, "?", to the property attribute string for
properties of protocols that are declared @optional.
(Previously https://reviews.llvm.org/D135273)
rdar://100463524
We have a new policy in place making links to private resources
something we try to avoid in source and test files. Normally, we'd
organically switch to the new policy rather than make a sweeping change
across a project. However, Clang is in a somewhat special circumstance
currently: recently, I've had several new contributors run into rdar
links around test code which their patch was changing the behavior of.
This turns out to be a surprisingly bad experience, especially for
newer folks, for a handful of reasons: not understanding what the link
is and feeling intimidated by it, wondering whether their changes are
actually breaking something important to a downstream in some way,
having to hunt down strangers not involved with the patch to impose on
them for help, accidental pressure from asking for potentially private
IP to be made public, etc. Because folks run into these links entirely
by chance (through fixing bugs or working on new features), there's not
really a set of problematic links to focus on -- all of the links have
basically the same potential for causing these problems. As a result,
this is an omnibus patch to remove all such links.
This was not a mechanical change; it was done by manually searching for
rdar, radar, radr, and other variants to find all the various
problematic links. From there, I tried to retain or reword the
surrounding comments so that we would lose as little context as
possible. However, because most links were just a plain link with no
supporting context, the majority of the changes are simple removals.
Differential Review: https://reviews.llvm.org/D158071
This allows use with non-0 address space stacks. llvm_ptr_ty should
never be used. This could use some more percolation up through mlir,
but this is enough to fix existing tests.
https://reviews.llvm.org/D156666
This is an ongoing series of commits that are reformatting our
Python code.
Reformatting is done with `black`.
If you end up having problems merging this commit because you
have made changes to a python file, the best way to handle that
is to run git checkout --ours <yourfile> and then reformat it
with black.
If you run into any problems, post to discourse about it and
we will try to help.
RFC Thread below:
https://discourse.llvm.org/t/rfc-document-and-standardize-python-code-style
Reviewed By: MatzeB
Differential Revision: https://reviews.llvm.org/D150761
This switches everything to use the memory attribute proposed in
https://discourse.llvm.org/t/rfc-unify-memory-effect-attributes/65579.
The old argmemonly, inaccessiblememonly and inaccessiblemem_or_argmemonly
attributes are dropped. The readnone, readonly and writeonly attributes
are restricted to parameters only.
The old attributes are auto-upgraded both in bitcode and IR.
The bitcode upgrade is a policy requirement that has to be retained
indefinitely. The IR upgrade is mainly there so it's not necessary
to update all tests using memory attributes in this patch, which
is already large enough. We could drop that part after migrating
tests, or retain it longer term, to make it easier to import IR
from older LLVM versions.
High-level Function/CallBase APIs like doesNotAccessMemory() or
setDoesNotAccessMemory() are mapped transparently to the memory
attribute. Code that directly manipulates attributes (e.g. via
AttributeList) on the other hand needs to switch to working with
the memory attribute instead.
Differential Revision: https://reviews.llvm.org/D135780
functions in getter/setter functions of non-trivial C struct properties
This fixes a bug where the getter/setter functions were doing a trivial
copy instead of calling the synthesized functions that copy non-trivial
C struct types.
This fixes https://github.com/llvm/llvm-project/issues/56680.
Differential Revision: https://reviews.llvm.org/D131701
This fixes a bug from https://reviews.llvm.org/D131424 that removed the implicit `_cmd` parameter as an argument to `objc_direct` method implementations. In many cases the generated getter/setter will call `objc_getProperty` or `objc_setProperty`, both of which require the selector of the getter/setter; since `_cmd` didn't automatically have backing storage, attempting to load the address asserted.
For direct property generated getters/setters, this now passes an undefined/uninitialized/poison value as the `_cmd` argument to `objc_getProperty`/`objc_setProperty`. Prior to removing the `_cmd` argument from the ABI of direct methods, it was left uninitialized/undefined; although references within hand-implemented methods would load the selector in the method prologue, generated getters/setters never did and just forwarded the undefined value that was passed as the argument.
This change keeps the generated code mostly similar to before, passing an uninitialized/undefined/poison value; for setters, the value argument may be moved to another register.
Added a test that triggers the assert prior to the implementation code.
Differential Revision: https://reviews.llvm.org/D135091
When `objc_direct` methods were implemented, the implicit `_cmd` parameter was left as an argument to the method implementation function, but was unset by callers; if the method body referenced the `_cmd` variable, a selector load would be emitted inside the body. However, this leaves an unused argument in the ABI, and is unnecessary.
This change removes the empty/unset argument, and if `_cmd` is referenced inside an `objc_direct` method it will emit local storage for the implicit variable. From the ABI perspective, `objc_direct` methods will have the implicit `self` parameter, immediately followed by whatever explicit arguments are defined on the method, rather than having one unset/undefined register in the middle.
Differential Revision: https://reviews.llvm.org/D131424
5ab6ee7599 assumed that if `RValue::isScalar()` returns true then `RValue::getScalarVal` will return a valid value. This is not the case when the return value is `void` and so void message returns would crash if they hit this path. This is triggered only for cases where the nil-handling path needs to do something non-trivial (destroy arguments that should be consumed by the callee).
Reviewed By: triplef
Differential Revision: https://reviews.llvm.org/D123898
Clang has traditionally allowed C programs to implicitly convert
integers to pointers and pointers to integers, despite it not being
valid to do so except under special circumstances (like converting the
integer 0, which is the null pointer constant, to a pointer). In C89,
this would result in undefined behavior per 3.3.4, and in C99 this rule
was strengthened to be a constraint violation instead. Constraint
violations are most often handled as an error.
This patch changes the warning to default to an error in all C modes
(it is already an error in C++). This gives us better security posture
by calling out potential programmer mistakes in code but still allows
users who need this behavior to use -Wno-error=int-conversion to retain
the warning behavior, or -Wno-int-conversion to silence the diagnostic
entirely.
Differential Revision: https://reviews.llvm.org/D129881
Some code [0] consider that trailing arrays are flexible, whatever their size.
Support for these legacy code has been introduced in
f8f6324983 but it prevents evaluation of
__builtin_object_size and __builtin_dynamic_object_size in some legit cases.
Introduce -fstrict-flex-arrays=<n> to have stricter conformance when it is
desirable.
n = 0: current behavior, any trailing array member is a flexible array. The default.
n = 1: any trailing array member of undefined, 0 or 1 size is a flexible array member
n = 2: any trailing array member of undefined or 0 size is a flexible array member
This takes into account two specificities of clang: array bounds as macro id
disqualify FAM, as well as non standard layout.
Similar patch for gcc discuss here: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101836
[0] https://docs.freebsd.org/en/books/developers-handbook/sockets/#sockets-essential-functions
This reverts commit 4e545bdb35.
The newly added test is the third infinite combine loop caused by
this change. In this case, it's a combination of the branch to
common dest and jump threading folds that keeps peeling off loop
iterations.
The core problem here is that we ideally would not thread over
loop backedges, both because it is potentially non-profitable
(it may break canonical loop structure) and because it may result
in these kinds of loops. Unfortunately, due to the lack of a
dominator tree in SimplifyCFG, there is no good way to prevent
this. While we have LoopHeaders, this is an optional structure and
we don't do a good job of keeping it up to date. It would be fine
for a profitability check, but is not suitable for a correctness
check.
So for now I'm just giving up here, as I don't see a good way to
robustly prevent infinite combine loops.
Fixes https://github.com/llvm/llvm-project/issues/56203.
Some code [0] consider that trailing arrays are flexible, whatever their size.
Support for these legacy code has been introduced in
f8f6324983 but it prevents evaluation of
__builtin_object_size and __builtin_dynamic_object_size in some legit cases.
Introduce -fstrict-flex-arrays=<n> to have stricter conformance when it is
desirable.
n = 0: current behavior, any trailing array member is a flexible array. The default.
n = 1: any trailing array member of undefined, 0 or 1 size is a flexible array member
n = 2: any trailing array member of undefined or 0 size is a flexible array member
n = 3: any trailing array member of undefined size is a flexible array member (strict c99 conformance)
Similar patch for gcc discuss here: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101836
[0] https://docs.freebsd.org/en/books/developers-handbook/sockets/#sockets-essential-functions
Instead, just pop the cleanups at the end of the asm statement.
This fixes an assertion failure in BuildStmtExpr. It also fixes a bug
where blocks and C compound literals were destructed at the end of the
asm statement instead of at the end of the enclosing scope.
Differential Revision: https://reviews.llvm.org/D125936
