This is a major change on how we represent nested name qualifications in
the AST.
* The nested name specifier itself and how it's stored is changed. The
prefixes for types are handled within the type hierarchy, which makes
canonicalization for them super cheap, no memory allocation required.
Also translating a type into nested name specifier form becomes a no-op.
An identifier is stored as a DependentNameType. The nested name
specifier gains a lightweight handle class, to be used instead of
passing around pointers, which is similar to what is implemented for
TemplateName. There is still one free bit available, and this handle can
be used within a PointerUnion and PointerIntPair, which should keep
bit-packing aficionados happy.
* The ElaboratedType node is removed, all type nodes in which it could
previously apply to can now store the elaborated keyword and name
qualifier, tail allocating when present.
* TagTypes can now point to the exact declaration found when producing
these, as opposed to the previous situation of there only existing one
TagType per entity. This increases the amount of type sugar retained,
and can have several applications, for example in tracking module
ownership, and other tools which care about source file origins, such as
IWYU. These TagTypes are lazily allocated, in order to limit the
increase in AST size.
This patch offers a great performance benefit.
It greatly improves compilation time for
[stdexec](https://github.com/NVIDIA/stdexec). For one datapoint, for
`test_on2.cpp` in that project, which is the slowest compiling test,
this patch improves `-c` compilation time by about 7.2%, with the
`-fsyntax-only` improvement being at ~12%.
This has great results on compile-time-tracker as well:

This patch also further enables other optimziations in the future, and
will reduce the performance impact of template specialization resugaring
when that lands.
It has some other miscelaneous drive-by fixes.
About the review: Yes the patch is huge, sorry about that. Part of the
reason is that I started by the nested name specifier part, before the
ElaboratedType part, but that had a huge performance downside, as
ElaboratedType is a big performance hog. I didn't have the steam to go
back and change the patch after the fact.
There is also a lot of internal API changes, and it made sense to remove
ElaboratedType in one go, versus removing it from one type at a time, as
that would present much more churn to the users. Also, the nested name
specifier having a different API avoids missing changes related to how
prefixes work now, which could make existing code compile but not work.
How to review: The important changes are all in
`clang/include/clang/AST` and `clang/lib/AST`, with also important
changes in `clang/lib/Sema/TreeTransform.h`.
The rest and bulk of the changes are mostly consequences of the changes
in API.
PS: TagType::getDecl is renamed to `getOriginalDecl` in this patch, just
for easier to rebasing. I plan to rename it back after this lands.
Fixes#136624
Fixes https://github.com/llvm/llvm-project/issues/43179
Fixes https://github.com/llvm/llvm-project/issues/68670
Fixes https://github.com/llvm/llvm-project/issues/92757
Add `NamespaceBaseDecl` as common base class of `NamespaceDecl` and
`NamespaceAliasDecl`. This simplifies `NestedNameSpecifier` a bit.
Co-authored-by: Matheus Izvekov <mizvekov@gmail.com>
The subheading for a destructor contained only the identifier. The tilde
must also be included as it is necessary to differentiate the destructor
from any constructors present.
rdar://129587608
Pointer types in function signatures must place the asterisk before the
identifier without a space in between. This patch removes the space and
also ensures that pointers to pointers are formatted correctly.
rdar://131780418
rdar://154533037
This PR fixes two crashes in ExtractAPI that occur when decls are
requested via libclang:
- A null-dereference would sometimes happen in
`DeclarationFragmentsBuilder::getFragmentsForClassTemplateSpecialization`
when the template being processed was loaded indirectly via a typedef,
with parameters filled in. The first commit loads the template parameter
locations ahead of time to perform a null check before dereferencing.
- An assertion (or another null-dereference) was happening in
`CXXRecordDecl::bases` when processing a forward-declaration (i.e. a
record without a definition). The second commit guards the use of
`bases` in `ExtractAPIVisitorBase::getBases` by first checking that the
decl in question has a complete definition.
The added test `extract-api-cursor-cpp` adds tests for these two
scenarios to protect against the crash in the future.
Fixes rdar://140592475, fixes rdar://123430367
When an anonymous type has a typedef we normally use the typedef's name
in places where we expect a named identifier in the symbol graph. This
extends this logic to apply to subheadings.
rdar://136690614
As specified in the docs,
1) raw_string_ostream is always unbuffered and
2) the underlying buffer may be used directly
( 65b13610a5226b84889b923bae884ba395ad084d for further reference )
* Don't call raw_string_ostream::flush(), which is essentially a no-op.
* Avoid unneeded calls to raw_string_ostream::str(), to avoid excess indirection.
Extension SGFs require the module system to be enabled in order to discover which module defines the extended external type.
This patch ensures the following:
- Associate symbols with their top level module name, and that only top level modules are considered as modules for emitting extension SGFs.
- Ensure we don't drop macro definitions that came from a submodule. To this end look at all defined macros in `PPCalbacks::EndOfMainFile` instead of relying on `PPCallbacks::MacroDefined` being called to detect a macro definition.
This is an enabler for https://github.com/llvm/llvm-project/pull/92855
This allows an NTTP default argument to be set as an arbitrary
TemplateArgument, not just an expression.
This allows template parameter packs to have default arguments in the
AST, even though the language proper doesn't support the syntax for it.
This allows NTTP default arguments to be other kinds of arguments, like
packs, integral constants, and such.
This is an enabler for a future patch.
This allows an type-parameter default argument to be set as an arbitrary
TemplateArgument, not just a type.
This allows template parameter packs to have default arguments in the
AST, even though the language proper doesn't support the syntax for it.
This will be used in a later patch which synthesizes template parameter
lists with arbitrary default arguments taken from template
specializations.
There are a few places we used SubsType, because we only had a type, now
we use SubstTemplateArgument.
SubstTemplateArgument was missing arguments for setting Instantiation
location and entity names.
Adding those is needed so we don't regress in diagnostics.
Previously we only generated declaration fragments for template type
parameters/arguments, this adds supports for most other possible
template parameters/arguments.
rdar://127732598
This changes the handling of anonymous TagDecls to the following rules:
- If the TagDecl is embedded in the declaration for some VarDecl (this
is the only possibility for RecordDecls), then pretend the child decls
belong to the VarDecl
- If it's an EnumDecl proceed as we did previously, i.e., embed it in
the enclosing DeclContext.
Additionally this fixes a few issues with declaration fragments not
consistently including "{ ... }" for anonymous TagDecls. To make testing
these additions easier this patch fixes some text declaration fragments
merging issues and updates tests accordingly.
rdar://121436298
Reenables b31414bf4f9898f7817a9fcf8a91f62ec26f3eaf.
Also adds a new warning for missing `--symbol-graph-dir` arg when
`--emit-extension-symbol-graphs` is provided. This also reverts the
commit that removed.
The names of template arguments in partial specializations or parameters
used as types might be mangled according to index and depth. Instead of
looping through parameter lists to find matches like we do now, they can
be deduced via their QualTypes or as written from the AST.
This extends ExtractAPI to take into account symbols defined in categories to types defined in an external module.
This introduces 2 new command line flags, `--symbol-graph-dir=DIR` and `--emit-extension-symbol-graphs`, when used together this generates additional symbol graph files at `DIR/ExtendedModule@ProductName.symbols.json` for each external module that is extended in this way.
Additionally this makes some cleanups to tests to make them more resilient and cleans up the `APISet` data structure.
When generating declaration fragments for types that use typedefs to
pointer types ensure that we keep the user-defined typedef form instead
of desugaring the typedef.
rdar://102137655
Ensure that block types get represented correctly in declaration
fragments, as block parameter names are important for documentation
clients we need a separate system from getFragmentsForType in order to
have access to full ParmVarDecls for the parameters.
rdar://118257401
This patch moves ElaboratedTypeKeyword before `Type` definition so that the enum is complete where bit-field for it is declared. It also converts it to scoped enum and removes `ETK_` prefix.
This patch moves `ArraySizeModifier` before `Type` declaration so that it's complete at `ArrayTypeBitfields` declaration. It's also converted to scoped enum along the way.
getFragmentsForType resulted in a bool typeIdentifier fragment to be spelled "_Bool".
This fixes the spelling to be "bool" and checks it in C and C++.
Reviewed By: dang
Differential Revision: https://reviews.llvm.org/D158474
Visit and serialize C++ fields by checking if a var template's context is a CXXRecordDecl in VisitVarTemplateDecl.
Depends on D158027
Reviewed By: dang
Differential Revision: https://reviews.llvm.org/D158029
Add records, serialization for global function templates and their specializations
Depends on D157350
Reviewed By: dang
Differential Revision: https://reviews.llvm.org/D157579
Serialize global C++ variable templates and specializations.
Depends on D157076
Reviewed By: dang
Differential Revision: https://reviews.llvm.org/D157350
Add has_template template, DeclarationFragmentBuilder functions, and tests for class templates, specializations/partial specs, and concepts.
Depends on D157007
Reviewed By: dang
Differential Revision: https://reviews.llvm.org/D157076
Reintroduce D153557 with fix for use-after-free from f4de606ef271 and minor changes.
Reviewed By: dang
Differential Revision: https://reviews.llvm.org/D157007
Use CRTP to enable creating statically dispatched subclasses of
ExtractAPIVisitor.
This enables adding extension points and customising the behavior more
easily.
This is used in CXExtractAPI.cpp to create a specialized visitor for
Libclang as well as streamlining the batch implementation in ExtractAPIConsumer.cpp
This is mainly adding an entry point to `SymbolGraphSerializer` at
`serializeSingleSymbolSGF` and exposing the necessary data to make this
possible. Additionaly there are some changes to how symbol kinds and
path components are serialized to make the usage more ergonomic in
`serializeSingleSymbolSGF`.
On the libclang side this introduces APIs to:
- create an APISet from a TU
- dispose of an APISet
- query an APISet for a single symbol SGF for a given USR.
- generate a single symbol SGF for a given CXCursor, this only traverses
the necessary AST nodes to construct the result as oppposed as going
through the entire AST.
Differential Revision: https://reviews.llvm.org/D139115