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
This offloads some test changes from another PR in order to facilitate
review.
- Adds some new tests.
- Cleans stray spaces and newlines on existing tests.
- Regenerates some AST json dumps, as the generator now includes
offsets.
These are an artifact of how types are structured but serve little
purpose, merely showing that the type is sugared in some way. For
example, ElaboratedType's existence means struct S gets printed as
'struct S':'struct S' in the AST, which is unnecessary visual clutter.
Note that skipping the second print when the types have the same string
matches what we do for diagnostics, where the aka will be skipped.
This patch adds -Wno-strict-prototypes to all of the test cases that
use functions without prototypes, but not as the primary concern of the
test. e.g., attributes testing whether they can/cannot be applied to a
function without a prototype, etc.
This is done in preparation for enabling -Wstrict-prototypes by
default.
None of these tests are really intended to test the file offset as much
as to test the structure. Making the regex allows this test to work
even if the file is checked out with CRLF line endings.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D119362
Mangled names are not meaningful for variables with local storage,
and may not be well defined (getting the mangled name for VLA
crashes the mangler). As such, do not include them in the JSON
dump.
This allows running update_cc_test_checks on some OpenMP tests again.
Fixes https://github.com/llvm/llvm-project/issues/49111.
Differential Revision: https://reviews.llvm.org/D116169
Without this, the combination of `-ast-dump=json` and `-ast-dump-filter FILTER` produces invalid JSON: the first line is a string that says `Dumping $SOME_DECL_NAME: `.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D108441
This renames the expression value categories from rvalue to prvalue,
keeping nomenclature consistent with C++11 onwards.
C++ has the most complicated taxonomy here, and every other language
only uses a subset of it, so it's less confusing to use the C++ names
consistently, and mentally remap to the C names when working on that
context (prvalue -> rvalue, no xvalues, etc).
Renames:
* VK_RValue -> VK_PRValue
* Expr::isRValue -> Expr::isPRValue
* SK_QualificationConversionRValue -> SK_QualificationConversionPRValue
* JSON AST Dumper Expression nodes value category: "rvalue" -> "prvalue"
Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
Reviewed By: rsmith
Differential Revision: https://reviews.llvm.org/D103720
Currently TypePrinter lumps anonymous classes and unnamed classes in one group "anonymous" this is not correct and can be confusing in some contexts.
Differential Revision: https://reviews.llvm.org/D96807
I missed clangd test suite and may need some time to get those working, so reverting for now.
This reverts commit ecb90b55454ee94733481247486729a504aa43a1.
Currently TypePrinter lumps anonymous classes and unnamed classes in one group "anonymous" this is not correct and can be confusing in some contexts.
Differential Revision: https://reviews.llvm.org/D96807
With https://reviews.llvm.org/D63376, we began storing the APValue
directly into the ConstantExpr object so that we could reuse the
calculated value later. However, it missed a case when not in C++11
mode but the expression is known to be constant.
I am planning to use this feature to make update_cc_test_checks.py less fragile
by obtaining the mangled names directly from -ast-dump=json. Currently,
it uses c-index-test which ignores the -triple=, etc. arguments that are
in the RUN: line and therefore does not generate checks for some targets.
The AST dump tests were updated using the following command:
`python $LLVM_BINDIR/gen_ast_dump_json_test.py --update --source $LLVM_SRC/clang/test/AST/*-json.*`
Reviewers: aaron.ballman
Reviewed By: aaron.ballman
Subscribers: rsmith, MaskRay, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D69564
This adds information about the offset within the source file to the given source location as well as information about the include file a location is from. These pieces of information allow for more efficient post-processing of JSON AST dumps.
llvm-svn: 374921
Because of multiple inheritance, a DeclContext pointer does not produce
the same pointer representation as a Decl pointer that references the
same AST Node.
When dumping the parentDeclContextId field of a node, convert the pointer
to Decl* first, so the id can be used to find the AST node it references.
Patch by Bert Belder.
llvm-svn: 370970
Rather than create JSON objects for source locations and ranges, we instead stream them out directly. This allows us to elide duplicate information (without JSON field reordering causing an issue) like file names and line numbers, similar to the text dump. This also adds token length information when dumping the source location.
llvm-svn: 364226
This also details what filters, if any, were used to generate the test output. Updates all the current JSON testing files to include the automated note.
llvm-svn: 364055