The previous implementation was insufficient for checking statement
attribute mutual exclusion because attributed statements do not collect
their attributes one-at-a-time in the same way that declarations do. So
the design that was attempting to check for mutual exclusion as each
attribute was processed would not ever catch a mutual exclusion in a
statement. This was missed due to insufficient test coverage, which has
now been added for the [[likely]] and [[unlikely]] attributes.
The new approach is to check all of attributes that are to be applied
to the attributed statement in a group. This required generating
another DiagnoseMutualExclusions() function into AttrParsedAttrImpl.inc.
Just because an attribute is a statement attribute doesn't mean it's
not also a declaration attribute. In Clang, there are not currently any
DeclOrStmtAttr attributes that require mutual exclusion checking, but
downstream clients discovered this issue.
Currently, when one or more attributes are mutually exclusive, the
developer adding the attribute has to manually emit diagnostics. In
practice, this is highly error prone, especially for declaration
attributes, because such checking is not trivial. Redeclarations
require you to write a "merge" function to diagnose mutually exclusive
attributes and most attributes get this wrong.
This patch introduces a table-generated way to specify that a group of
two or more attributes are mutually exclusive:
def : MutualExclusions<[Attr1, Attr2, Attr3]>;
This works for both statement and declaration attributes (but not type
attributes) and the checking is done either from the common attribute
diagnostic checking code or from within mergeDeclAttribute() when
merging redeclarations.
Clang currently automates a fair amount of diagnostic checking for
declaration attributes based on the declarations in Attr.td. It checks
for things like subject appertainment, number of arguments, language
options, etc. This patch uses the same machinery to perform diagnostic
checking on statement attributes.
This attribute permits a typedef to be associated with a class template
specialization as a preferred way of naming that class template
specialization. This permits us to specify that (for example) the
preferred way to express 'std::basic_string<char>' is as 'std::string'.
The attribute is applied to the various class templates in libc++ that have
corresponding well-known typedef names.
This is a re-commit. The previous commit was reverted because it exposed
a pre-existing bug that has since been fixed / worked around; see
PR48434.
Differential Revision: https://reviews.llvm.org/D91311
This change exposed a pre-existing issue with deserialization cycles
caused by a combination of attributes and template instantiations
violating the deserialization ordering restrictions; see PR48434 for
details.
A previous commit attempted to work around PR48434, but appears to have
only been a partial fix, and fixing this properly seems non-trivial.
Backing out for now to unblock things.
This reverts commit 98f76adf4e and
commit a64c26a47a.
This is really just a workaround for a more fundamental issue in the way
we deserialize attributes. See PR48434 for details.
Also fix tablegen code generator to produce more correct indentation to
resolve buildbot issues with -Werror=misleading-indentation firing
inside the generated code.
This attribute permits a typedef to be associated with a class template
specialization as a preferred way of naming that class template
specialization. This permits us to specify that (for example) the
preferred way to express 'std::basic_string<char>' is as 'std::string'.
The attribute is applied to the various class templates in libc++ that have
corresponding well-known typedef names.
Differential Revision: https://reviews.llvm.org/D91311
There are two factory functions used to create a semantic attribute,
Create() and CreateImplicit(). CreateImplicit() does not need to
specify the source range of the attribute since it's an implicitly-
generated attribute. The same logic does not apply to Create(), so
this removes the default argument from those declarations to avoid
accidentally creating a semantic attribute without source location
information.
ns_error_domain can be used by, e.g. NS_ERROR_ENUM, in order to
identify a global declaration representing the domain constant.
Introduces the attribute, Sema handling, diagnostics, and test case.
This is cherry-picked from a14779f504
and adapted to updated Clang APIs.
Reviewed By: gribozavr2, aaron.ballman
Differential Revision: https://reviews.llvm.org/D84005
WG14 N2481 was adopted with minor modifications at the latest WG14 meetings.
The only modification to the paper was to correct the date for the deprecated
attribute to be 201904L (the corrected date value will be present in WG14
N2553 when it gets published).
ClangAttrEmitter.cpp generates ParsedAttr derived classes with virtual overrides in them (which end up in AttrParsedAttrImpl.inc); this patch ensures these generated functions are marked override, and not (redundantly) virtual.
I hesitate to say NFC since this does of course affect the behavior of the generator code, but the generated code behaves the same as it did before, so it's NFC in that sense.
Differential Revision: https://reviews.llvm.org/D83616
GCC 10.1 introduced support for the [[]] style spelling of attributes in C
mode. Similar to how GCC supports __attribute__((foo)) as [[gnu::foo]] in
C++ mode, it now supports the same spelling in C mode as well. This patch
makes a change in Clang so that when you use the GCC attribute spelling,
the attribute is automatically available in all three spellings by default.
However, like Clang, GCC has some attributes it only recognizes in C++ mode
(specifically, abi_tag and init_priority), which this patch also honors.
Currently square-bracket-style (CXX11/C2X) attribute names are normalised to
start with :: if they don't have a namespace. This is a bit odd, as such
names are rejected when parsing, so don't do this.
Differential Revision: https://reviews.llvm.org/D76704
This makes it possible for plugin attributes to actually do something, and also
removes a lot of boilerplate for simple attributes in SemaDeclAttr.cpp.
Differential Revision: https://reviews.llvm.org/D31342
Discovered in a downstream, it is often useful to have slightly
different semantics for an attribute based on its namespace, however our
spelling infrastructure doesn't consider namespace when deciding to
elide the enum list. The result is that the solution for a case where
an attribute has slightly different semantics based on a namespace
requires checking against the integer value, which is fragile.
This patch makes us always emit the spelling enum if there is more than
1 and we're generating the header.
Differential Revision: https://reviews.llvm.org/D76289
The name field is optional if the custom code is supplied, so this updates the
documentation for LangOpt and introduces a tablegen warning if both custom code
and a language option name are supplied.
After this change, clang spends ~200ms parsing Attrs.inc instead of
~560ms. A large part of the cost was from the StringSwitch
instantiations, but this is a good way to avoid similar problems in the
future.
Reviewed By: aaron.ballman, rjmccall
Differential Revision: https://reviews.llvm.org/D76040
When constructing a ParsedAttr the ParsedAttrInfo gets looked up in the
AttrInfoMap, which is auto-generated using tablegen. If that lookup fails then
we look through the ParsedAttrInfos that plugins have added to the registry and
check if any has a spelling that matches.
Differential Revision: https://reviews.llvm.org/D31338
This doesn't do anything on its own, but it's the first step towards
allowing plugins to define attributes. It does simplify the
ParsedAttrInfo generation in ClangAttrEmitter a little though.
Differential Revision: https://reviews.llvm.org/D31337
This patch implements an almost complete handling of OpenMP
contexts/traits such that we can reuse most of the logic in Flang
through the OMPContext.{h,cpp} in llvm/Frontend/OpenMP.
All but construct SIMD specifiers, e.g., inbranch, and the device ISA
selector are define in `llvm/lib/Frontend/OpenMP/OMPKinds.def`. From
these definitions we generate the enum classes `TraitSet`,
`TraitSelector`, and `TraitProperty` as well as conversion and helper
functions in `llvm/lib/Frontend/OpenMP/OMPContext.{h,cpp}`.
The above enum classes are used in the parser, sema, and the AST
attribute. The latter is not a collection of multiple primitive variant
arguments that contain encodings via numbers and strings but instead a
tree that mirrors the `match` clause (see `struct OpenMPTraitInfo`).
The changes to the parser make it more forgiving when wrong syntax is
read and they also resulted in more specialized diagnostics. The tests
are updated and the core issues are detected as before. Here and
elsewhere this patch tries to be generic, thus we do not distinguish
what selector set, selector, or property is parsed except if they do
behave exceptionally, as for example `user={condition(EXPR)}` does.
The sema logic changed in two ways: First, the OMPDeclareVariantAttr
representation changed, as mentioned above, and the sema was adjusted to
work with the new `OpenMPTraitInfo`. Second, the matching and scoring
logic moved into `OMPContext.{h,cpp}`. It is implemented on a flat
representation of the `match` clause that is not tied to clang.
`OpenMPTraitInfo` provides a method to generate this flat structure (see
`struct VariantMatchInfo`) by computing integer score values and boolean
user conditions from the `clang::Expr` we keep for them.
The OpenMP context is now an explicit object (see `struct OMPContext`).
This is in anticipation of construct traits that need to be tracked. The
OpenMP context, as well as the `VariantMatchInfo`, are basically made up
of a set of active or respectively required traits, e.g., 'host', and an
ordered container of constructs which allows duplication. Matching and
scoring is kept as generic as possible to allow easy extension in the
future.
---
Test changes:
The messages checked in `OpenMP/declare_variant_messages.{c,cpp}` have
been auto generated to match the new warnings and notes of the parser.
The "subset" checks were reversed causing the wrong version to be
picked. The tests have been adjusted to correct this.
We do not print scores if the user did not provide one.
We print spaces to make lists in the `match` clause more legible.
Reviewers: kiranchandramohan, ABataev, RaviNarayanaswamy, gtbercea, grokos, sdmitriev, JonChesterfield, hfinkel, fghanim
Subscribers: merge_guards_bot, rampitec, mgorny, hiraditya, aheejin, fedor.sergeev, simoncook, bollu, guansong, dexonsmith, jfb, s.egerton, llvm-commits, cfe-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D71830
This is how it should've been and brings it more in line with
std::string_view. There should be no functional change here.
This is mostly mechanical from a custom clang-tidy check, with a lot of
manual fixups. It uncovers a lot of minor inefficiencies.
This doesn't actually modify StringRef yet, I'll do that in a follow-up.
There are three significant changes here:
- Most of the methods to read various embedded structures (`APInt`,
`NestedNameSpecifier`, `DeclarationName`, etc.) have been moved
from `ASTReader` to `ASTRecordReader`. This cleans up quite a
bit of code which was passing around `(F, Record, Idx)` arguments
everywhere or doing explicit indexing, and it nicely parallels
how it works on the writer side. It also sets us up to then move
most of these methods into the `BasicReader`s that I'm introducing
as part of abstract serialization.
As part of this, several of the top-level reader methods (e.g.
`readTypeRecord`) have been converted to use `ASTRecordReader`
internally, which is a nice readability improvement.
- I've standardized most of these method names on `readFoo` rather
than `ReadFoo` (used in some of the helper structures) or `GetFoo`
(used for some specific types for no apparent reason).
- I've changed a few of these methods to return their result instead
of reading into an argument passed by reference. This is partly
for general consistency and partly because it will make the
metaprogramming easier with abstract serialization.
r371875 moved some functionality around to a Basic header file, but
didn't move its definitions as well. This patch moves some things
around so that shared library building can work.
llvm-svn: 371985
Apparently Clang complains about the name hiding here in a way that my
GCC build does not, so a shocking number of buildbots decided to tell me
about it. Change the name of the variable to prevent the name hiding
and hope we don't have to fix this again.
llvm-svn: 371876
In order to enable future improvements to our attribute diagnostics,
this moves info from ParsedAttr into CommonAttributeInfo, then makes
this type the base of the *Attr and ParsedAttr types. Quite a bit of
refactoring took place, including removing a bunch of redundant Spelling
Index propogation.
Differential Revision: https://reviews.llvm.org/D67368
llvm-svn: 371875
Now that we've moved to C++14, we no longer need the llvm::make_unique
implementation from STLExtras.h. This patch is a mechanical replacement
of (hopefully) all the llvm::make_unique instances across the monorepo.
Differential revision: https://reviews.llvm.org/D66259
llvm-svn: 368942
Summary:
This is the first part of work announced in
"[RFC] Adding lifetime analysis to clang" [0],
i.e. the addition of the [[gsl::Owner(T)]] and
[[gsl::Pointer(T)]] attributes, which
will enable user-defined types to participate in
the lifetime analysis (which will be part of the
next PR).
The type `T` here is called "DerefType" in the paper,
and denotes the type that an Owner owns and a Pointer
points to. E.g. `std::vector<int>` should be annotated
with `[[gsl::Owner(int)]]` and
a `std::vector<int>::iterator` with `[[gsl::Pointer(int)]]`.
[0] http://lists.llvm.org/pipermail/cfe-dev/2018-November/060355.html
Reviewers: gribozavr
Subscribers: xazax.hun, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D63954
llvm-svn: 367040
Summary:
Add support for the C++2a [[no_unique_address]] attribute for targets using the Itanium C++ ABI.
This depends on D63371.
Reviewers: rjmccall, aaron.ballman
Subscribers: dschuff, aheejin, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D63451
llvm-svn: 363976
Swift requires certain classes to be not just initialized lazily on first
use, but actually allocated lazily using information that is only available
at runtime. This is incompatible with ObjC class initialization, or at least
not efficiently compatible, because there is no meaningful class symbol
that can be put in a class-ref variable at load time. This leaves ObjC
code unable to access such classes, which is undesirable.
objc_class_stub says that class references should be resolved by calling
a new ObjC runtime function with a pointer to a new "class stub" structure.
Non-ObjC compilers (like Swift) can simply emit this structure when ObjC
interop is required for a class that cannot be statically allocated,
then apply this attribute to the `@interface` in the generated ObjC header
for the class.
This attribute can be thought of as a generalization of the existing
`objc_runtime_visible` attribute which permits more efficient class
resolution as well as supporting the additon of categories to the class.
Subclassing these classes from ObjC is currently not allowed.
Patch by Slava Pestov!
llvm-svn: 362054
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
With commit r351627, LLVM gained the ability to apply (existing) IPO
optimizations on indirections through callbacks, or transitive calls.
The general idea is that we use an abstraction to hide the middle man
and represent the callback call in the context of the initial caller.
It is described in more detail in the commit message of the LLVM patch
r351627, the llvm::AbstractCallSite class description, and the
language reference section on callback-metadata.
This commit enables clang to emit !callback metadata that is
understood by LLVM. It does so in three different cases:
1) For known broker functions declarations that are directly
generated, e.g., __kmpc_fork_call for the OpenMP pragma parallel.
2) For known broker functions that are identified by their name and
source location through the builtin detection, e.g.,
pthread_create from the POSIX thread API.
3) For user annotated functions that carry the "callback(callee, ...)"
attribute. The attribute has to include the name, or index, of
the callback callee and how the passed arguments can be
identified (as many as the callback callee has). See the callback
attribute documentation for detailed information.
Differential Revision: https://reviews.llvm.org/D55483
llvm-svn: 351629
Remove now-vestigial dumpType and dumpBareDeclRef methods. The old
tablegen generated code used to expect them to be present, but the new
generated code has no such requirement.
Reviewers: aaron.ballman
Subscribers: mgorny, cfe-commits
Differential Revision: https://reviews.llvm.org/D55492
llvm-svn: 350958
Aaron Ballman