95 Commits

Author SHA1 Message Date
Matheus Izvekov
91cdd35008
[clang] Improve nested name specifier AST representation (#147835)
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:

![image](https://github.com/user-attachments/assets/700dce98-2cab-4aa8-97d1-b038c0bee831)

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
2025-08-09 05:06:53 -03:00
Younan Zhang
9ef2ac3ad1
[clangd] Handle lambda scopes inside Node::getDeclContext() (#76329)
We used to consider the `DeclContext` for selection nodes inside a
lambda as the enclosing scope of the lambda expression, rather than the
lambda itself.

For example,

```cpp
void foo();
auto lambda = [] {
  return ^foo();
};
```

where `N` is the selection node for the expression `foo()`,
`N.getDeclContext()` returns the `TranslationUnitDecl` previously, which
IMO is wrong, since the method `operator()` of the lambda is closer.

Incidentally, this fixes a glitch in add-using-declaration tweaks.
(Thanks @HighCommander4 for the test case.)
2024-01-11 16:59:18 +08:00
Sam McCall
a8c9b9f140 [clangd] Support ConceptReference in generic AST wrangling code
Now we can store it in DynTypedNode, we can target these nodes
(SelectionTree) and resolve them (FindTarget).
This makes Hover, go-to-def etc work in all(?) cases.

Also support it in DumpAST.

Differential Revision: https://reviews.llvm.org/D159299
2023-09-04 14:58:25 +02:00
serge-sans-paille
984b800a03
Move from llvm::makeArrayRef to ArrayRef deduction guides - last part
This is a follow-up to https://reviews.llvm.org/D140896, split into
several parts as it touches a lot of files.

Differential Revision: https://reviews.llvm.org/D141298
2023-01-10 11:47:43 +01:00
Kazu Hirata
f71ffd3b73 [clang-tools-extra] Use std::optional instead of llvm::Optional (NFC)
This patch replaces (llvm::|)Optional< with std::optional<.  I'll post
a separate patch to clean up the "using" declarations, #include
"llvm/ADT/Optional.h", etc.

This is part of an effort to migrate from llvm::Optional to
std::optional:

https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716
2023-01-07 20:19:42 -08:00
Kazu Hirata
71f557355d [clang-tools-extra] Add #include <optional> (NFC)
This patch adds #include <optional> to those files containing
llvm::Optional<...> or Optional<...>.

I'll post a separate patch to actually replace llvm::Optional with
std::optional.

This is part of an effort to migrate from llvm::Optional to
std::optional:

https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716
2023-01-07 20:02:20 -08:00
Kazu Hirata
059a23c0f0 [clang-tools-extra] Use std::nullopt instead of None (NFC)
This patch mechanically replaces None with std::nullopt where the
compiler would warn if None were deprecated.  The intent is to reduce
the amount of manual work required in migrating from Optional to
std::optional.

This is part of an effort to migrate from llvm::Optional to
std::optional:

https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716
2022-12-03 11:54:50 -08:00
Rageking8
c8f4792510
Fix dupe word typos
This revision fixes typos where there are 2 consecutive words which are duplicated.
There should be no code changes in this revision (only changes to comments and docs).
Do let me know if there are any undesirable changes in this revision. Thanks.
2022-11-08 15:29:12 +01:00
Sam McCall
62116c8f0b [clangd] consider ~^foo() to target the destructor, not the type
This behavior was once deliberate, but i've yet to find someone who likes it.
The reference behavior is unchanged: the `foo` within ~foo is still considered
a reference to the type. This means rename etc still works.

fixes https://github.com/clangd/clangd/issues/179

Differential Revision: https://reviews.llvm.org/D136212
2022-10-19 14:12:31 +02:00
Sam McCall
13b2a0c69b [clangd] Support hover on __func__ etc (PredefinedExpr)
Expose these as variables as that's what the standard calls them (and D131175).

To make this work, we also fix a bug in SelectionTree: PredefinedExpr has
an implicit/invisible StringLiteral, and SelectionTree should not traverse
implicit things.

Reviewed By: ckandeler

Differential Revision: https://reviews.llvm.org/D132135
2022-08-19 14:51:46 +02:00
Ilya Biryukov
2b833d4086 [AST] Improve traversal of concepts and concept requirements
- Do not traverse concept decl inside `AutoType`. We only traverse
  declaration and definitions, not references to a declaration.
- Do not visit implicit AST node the relevant traversal mode.
- Add traversal extension points for concept requirements.
- Renamed `TraverseConceptReference` to mark as helper to share
  the code. Having an extension point there seems confusing given that
  there are many concept refences in the AST that do not call the
  helper. Those are `AutoType`, `AutoTypeLoc` and constraint requirements.

Only clangd code requires an update.

There are no use-cases for concept requirement traversals yet, but
I added them in the earlier version of the patch and decided to keep
them for completeness.

Reviewed By: sammccall

Differential Revision: https://reviews.llvm.org/D124532
2022-04-28 09:33:26 +00:00
Christopher Di Bella
e9a902c7f7 Revert "Revert "Revert "[clang][pp] adds '#pragma include_instead'"""
> Includes regression test for problem noted by @hans.
> is reverts commit 973de71.
>
> Differential Revision: https://reviews.llvm.org/D106898

Feature implemented as-is is fairly expensive and hasn't been used by
libc++. A potential reimplementation is possible if libc++ become
interested in this feature again.

Differential Revision: https://reviews.llvm.org/D123885
2022-04-22 16:37:20 +00:00
David Goldman
54a962bbfe [clangd] Use ObjCProtocolLoc for generalized ObjC protocol support
This removes clangd's existing workaround in favor of proper support
via the newly added `ObjCProtocolLoc`. This improves support by
allowing clangd to properly identify which protocol is selected
now that `ObjCProtocolLoc` gets its own ASTNode.

Differential Revision: https://reviews.llvm.org/D119366
2022-02-18 15:24:00 -05:00
Haojian Wu
4cb1686bfe [clangd] Fix a selection tree crash for unmatched-bracket code.
Fixes https://github.com/clangd/clangd/issues/999

Differential Revision: https://reviews.llvm.org/D118322
2022-01-27 21:21:40 +01:00
Haojian Wu
55b702c37b [clangd] NFC, emit source ranges in selection debug messages.
It will make the output more versbose, but I found that these are useful
information when debugging selection tree.

Differential Revision: https://reviews.llvm.org/D117475
2022-01-19 16:06:58 +01:00
Jan Svoboda
c6fb636667 [clangd][clang-tidy] Remove uses of std::vector<bool>
LLVM Programmer’s Manual strongly discourages the use of `std::vector<bool>` and suggests `llvm::BitVector` as a possible replacement.

This patch does just that for clangd and clang-tidy.

Reviewed By: dexonsmith

Differential Revision: https://reviews.llvm.org/D117119
2022-01-18 17:59:40 +01:00
Haojian Wu
fd598e1859 [clangd] Bring back early-claim approach to fix a selection-tree regression.
The early-claim hack was removed in 96f5cc1ee417f863f85756d1e56b1bed1bd76a7e,
we see a regression about captured var-decl in lambda.

Fixes https://github.com/clangd/clangd/issues/990.

Differential Revision: https://reviews.llvm.org/D117472
2022-01-18 10:22:26 +01:00
Sam McCall
4dedd82cc9 Re-land [clangd] Elide even more checks in SelectionTree.
This reverts commit 1093b9f2e9842982d97534940a643e3a4657c60b.

Fix added for implicit-include case.
2022-01-17 15:26:28 +01:00
Kadir Cetinkaya
1093b9f2e9
Revert "[clangd] Elide even more checks in SelectionTree."
This reverts commit 07f9fb8b51417ec3e6f46508e1b5ef78287b32ad.
2022-01-14 14:32:43 +01:00
Sam McCall
07f9fb8b51 [clangd] Elide even more checks in SelectionTree.
During pop() we convert nodes into spans of expanded syntax::Tokens.
If we precompute a range of plausible (expanded) tokens, then we can do an
extremely cheap approximate hit-test against it, because syntax::Tokens are
ordered by pointer.

This would seem not to buy anything (we don't enter nodes unless they overlap
the selection), but in fact the spans we have are for *newly* claimed ranges
(i.e. those unclaimed by any child node).

So if you have:
   { { [[2+2]]; } }
then all of the CompoundStmts pass the hit test and are pushed, but we skip
full hit-testing of the brackets during pop() as they lie outside the range.

This is ~10x average speedup for selectiontree on a bad case I've seen
(large gtest file).

Differential Revision: https://reviews.llvm.org/D117107
2022-01-13 22:27:51 +01:00
Sam McCall
fc7a9f36a9 [clangd] Ignore cvr-qualifiers in selection.
The AST doesn't track their locations, and the default behavior of attributing
them to the lexically-enclosing node is sloppy and often inaccurate.

Also add a couple of passing test cases for declarators that weren't obvious.

Differential Revision: https://reviews.llvm.org/D117185
2022-01-13 15:08:50 +01:00
Sam McCall
2b2dbe6126 [clangd] Selection: Prune gtest TEST()s earlier
When searching for AST nodes that may overlap the selection, mayHit() was only
attempting to prune nodes whose begin/end are both in the main file.

While failing to prune never gives wrong results, it hurts performance.
In GTest unit-tests, `TEST()` macros at the top level declare classes.
These were never pruned and we traversed *every* such class for any selection.

We fix this by reasoning about what tokens such a node might claim.
They must lie within its ultimate macro expansion range, so if this doesn't
overlap with the selection, we can prune the node.

Differential Revision: https://reviews.llvm.org/D116978
2022-01-13 13:58:42 +01:00
Sam McCall
1e9b837585 [clangd] Save more getFileID in Selection
This saves about 10% of SelectionVisitor::pop().
2022-01-11 11:01:54 +01:00
Sam McCall
22ac067b2d [clangd] Small optimization in SelectionTree
This seems to be strictly faster in all cases. Before fixing D116978 it
was one of the hot paths, and may become one again.
2022-01-11 10:18:44 +01:00
Haojian Wu
4a4b8e4f99 [AST] Add more source information for DecltypeTypeLoc.
Adds the paren source location, and removes the hack in clangd.

Differential Revision: https://reviews.llvm.org/D116793
2022-01-10 09:34:18 +01:00
Sam McCall
bb10e03fba
[clangd] Refine comment on declarator ranges 2022-01-05 16:00:13 +01:00
Haojian Wu
7632d19ada [clangd] Fix typos in the SelectionTree comment. 2022-01-05 15:50:07 +01:00
Sam McCall
96f5cc1ee4 [clangd] Handle declarators more consistently in Selection.
Because declarators nest inside-out, we logically need to claim tokens for
parent declarators logically before child ones.
This is the ultimate reason we had problems with DeclaratorDecl, ArrayType etc.

However actually changing the order of traversal is hard, especially for nodes
that have both declarator and non-declarator children.
Since there's only a few TypeLocs corresponding to declarators, we just
have them claim the exact tokens rather than rely on nesting.

This fixes handling of complex declarators, like
`int (*Fun(OuterT^ype))(InnerType);`.

This avoids the need for the DeclaratorDecl early-claim hack, which is
removed.
Unfortunately the DeclaratorDecl early-claims were covering up an AST
anomaly around CXXConstructExpr, so we need to fix that up too.

Based on D116623 and D116618

Differential Revision: https://reviews.llvm.org/D116630
2022-01-05 15:40:47 +01:00
Haojian Wu
cb9ccd38c5 [clangd] Move the selection decltype hack to getSourceRange.
Previously, it was in canSafelySkipNode, which is only used to decide
whether we should descend into it and its children, and we still used
the incomplete Decltypeloc.getSourceRange() to claim tokens, which will
cause some tokens were not claimed correctly.

Separate a change of https://reviews.llvm.org/D116536

Reviewed By: sammccall

Differential Revision: https://reviews.llvm.org/D116586
2022-01-04 12:11:58 +01:00
Haojian Wu
20f8f46c60 [clangd] Fix selection on multi-dimensional array.
This involves separating out the concepts of "which tokens should we
descend into this node for" vs "which tokens should this node claim".

Reviewed By: sammccall

Differential Revision: https://reviews.llvm.org/D116218
2022-01-04 11:53:42 +01:00
Christian Kühnel
7aa2ce0fab [NFC][clangd] fix clang-tidy finding on isa_and_nonnull
This is a cleanup of the only llvm-prefer-isa-or-dyn-cast-in-conditionals finding in the clangd code base. This patch was created by automatically applying the fixes from clang-tidy.

Differential Revision: https://reviews.llvm.org/D113899
2021-11-18 09:16:54 +00:00
Christian Kühnel
ec4a2c9565 [NFC][clangd] cleanup llvm-else-after-return findings
Cleanup of clang-tidy findings: removing "else" after a return statement
to improve readability of the code.

This patch was created by applying the clang-tidy fixes automatically.

Differential Revision: https://reviews.llvm.org/D113892
2021-11-17 14:37:03 +00:00
Kadir Cetinkaya
3d735480bd
[clangd] SelectionTree should prefer lexical declcontext
This is important especially for code that tries to traverse scopes as
written in code, which is the contract SelectionTree tries to satisfy.

Differential Revision: https://reviews.llvm.org/D112712
2021-10-28 17:39:35 +02:00
Kadir Cetinkaya
512aa84850
[clangd] Handle members of anon structs in SelectionTree
References to fields inside anon structs contain an implicit children
for the container, which has the same SourceLocation with the field.
This was resulting in SelectionTree always picking the anon-struct rather than
the field as the selection.

This patch prevents that by claiming the range for the field early.

https://github.com/clangd/clangd/issues/877.

Differential Revision: https://reviews.llvm.org/D110825
2021-10-01 12:38:18 +02:00
Sam McCall
bb81e7083d [clangd] Add basic support for attributes (selection, hover)
These aren't terribly common, but we currently mishandle them badly.
Not only do we not recogize the attributes themselves, but we often end up
selecting some node other than the parent (because source ranges aren't accurate
in the presence of attributes).

Differential Revision: https://reviews.llvm.org/D89785
2021-08-06 22:49:14 +02:00
David Blaikie
1def2579e1 PR51018: Remove explicit conversions from SmallString to StringRef to future-proof against C++23
C++23 will make these conversions ambiguous - so fix them to make the
codebase forward-compatible with C++23 (& a follow-up change I've made
will make this ambiguous/invalid even in <C++23 so we don't regress
this & it generally improves the code anyway)
2021-07-08 13:37:57 -07:00
Sam McCall
bb41f85691 [clangd] Correct SelectionTree behavior around anonymous field access.
struct A { struct { int b; }; };
A().^b;

This should be considered a reference to b, but currently it's
considered a reference to the anonymous struct field.

Fixes https://github.com/clangd/clangd/issues/798

Differential Revision: https://reviews.llvm.org/D104376
2021-06-30 17:34:48 +02:00
Nathan James
d92413a45e
[clangd] Selection handles CXXBaseSpecifier
Selection now includes the virtual and access modifier as part of their range for cxx base specifiers.

Reviewed By: sammccall

Differential Revision: https://reviews.llvm.org/D95231
2021-01-26 18:58:53 +00:00
Alexander Kornienko
027899dab6 Remove references to the ast_type_traits namespace
Follow up to cd62511496938e33c061c90796dd23a5288ff843 /
https://reviews.llvm.org/D74499

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D92994
2020-12-11 00:58:46 +01:00
Kirill Bobyrev
ee02e20c08
[clangd] NFC: Use SmallVector<T> where possible
SmallVector<T> with default size is now the recommended version (D92522).

Reviewed By: sammccall

Differential Revision: https://reviews.llvm.org/D92788
2020-12-10 13:36:49 +01:00
Haojian Wu
1df0677e6a [clangd] Add language metrics for recovery AST usage.
Differential Revision: https://reviews.llvm.org/D92157
2020-12-07 10:52:05 +01:00
David Goldman
d5c022d846 [clangd][ObjC] Support nullability annotations
Nullability annotations are implmented using attributes; previusly
clangd would skip over AttributedTypeLoc since their location
points to the attribute instead of the modified type.

Also add some test cases for this.

Differential Revision: https://reviews.llvm.org/D89579
2020-10-20 17:36:32 -04:00
Nathan Ridge
70d583ad12 [clangd] Have template template arguments target their referenced template decl
Fixes https://github.com/clangd/clangd/issues/473

Differential Revision: https://reviews.llvm.org/D85503
2020-08-10 13:27:23 -04:00
Haojian Wu
61d664c938 Fix clangd build, NFC 2020-07-20 15:13:20 +02:00
Sam McCall
72f2fb1db4 [clangd] Exclude preprocessed-to-nothing tokens from selection
This prevents selection of empty preprocessor entities (like #define directives,
or text in disabled sections) creating a selection in the parent element.

Summary: Based on D83508 by Aleksandr Platonov.

Reviewers: ArcsinX, kadircet

Subscribers: ilya-biryukov, MaskRay, jkorous, arphaman, usaxena95, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D84012
2020-07-20 14:50:12 +02:00
Haojian Wu
26cf6c1513 [clangd] Add metrics for recovery-expr type propagation.
Differential Revision: https://reviews.llvm.org/D83657
2020-07-13 11:26:45 +02:00
Sam McCall
e3e15836af [clangd] Tidy up SelectionTree dumps with newlines 2020-05-19 01:48:01 +02:00
Haojian Wu
774acdfb8c [clangd] Add metrics for selection tree and recovery expressions.
Reviewers: sammccall

Subscribers: ilya-biryukov, MaskRay, jkorous, arphaman, kadircet, usaxena95, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D79701
2020-05-12 16:14:48 +02:00
Sam McCall
ad97ccf6b2 [clangd] Move non-clang base pieces into separate support/ lib. NFCI
Summary:
This enforces layering, reduces a sprawling clangd/ directory, and makes life
easier for embedders.

Reviewers: kbobyrev

Subscribers: mgorny, ilya-biryukov, javed.absar, MaskRay, jkorous, arphaman, jfb, kadircet, usaxena95, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D79014
2020-04-29 15:57:12 +02:00
Kadir Cetinkaya
e6b8181895
[clangd] Fix early selection for non-vardecl declarators
Summary:
Selection tree was performing an early claim only for VarDecls, but
there are other cases where we can have declarators, e.g. FieldDecls. This patch
extends the early claim logic to all types of declarators.

Fixes https://github.com/clangd/clangd/issues/292

Reviewers: sammccall

Subscribers: ilya-biryukov, MaskRay, jkorous, arphaman, usaxena95, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D75106
2020-03-04 11:01:35 +01:00