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
…heck
One typically only wants to perform renaming operations in user code,
not in system headers (which are out of the user's control). Let's skip
those altogether.
This leads to performance improvements in clang-tidy. As a benchmark, I
run all checks on a .cpp file that #includes all C++ standard headers.
On trunk:
```
Suppressed 213362 warnings (213362 in non-user code).
real 0m14.422s
user 0m14.236s
sys 0m0.184s
```
On this patch:
```
Suppressed 75411 warnings (75411 in non-user code).
real 0m12.472s
user 0m12.334s
sys 0m0.136s
```
Co-authored-by: Carlos Gálvez <carlos.galvez@zenseact.com>
Add `NamespaceBaseDecl` as common base class of `NamespaceDecl` and
`NamespaceAliasDecl`. This simplifies `NestedNameSpecifier` a bit.
Co-authored-by: Matheus Izvekov <mizvekov@gmail.com>
Added `.clang-tidy` config as discussed in
[RFC](https://discourse.llvm.org/t/rfc-create-hardened-clang-tidy-config-for-clang-tidy-directory/87247).
Added `bugprone`, `readability`, `modernize`, `performance` checks that
didn't create many warnings.
Fixed minor warnings to make `/clang-tidy` directory complaint with
`clang-tidy-20`.
Disabled checks will be enabled in future PRs after fixing their
warnings.
Member function templates defined out-of-line were resulting in
conflicting naming failures with overlapping usage sets. With this
change, out-of-line definitions are treated as a usage of the failure
which is the inline declaration.
I'm planning to remove StringRef::equals in favor of
StringRef::operator==.
- StringRef::operator==/!= outnumber StringRef::equals by a factor of
276 under llvm-project/ in terms of their usage.
- The elimination of StringRef::equals brings StringRef closer to
std::string_view, which has operator== but not equals.
- S == "foo" is more readable than S.equals("foo"), especially for
!Long.Expression.equals("str") vs Long.Expression != "str".
The handling of renaming failures and multiple usages related to those
failures is currently spread over several functions. Identifying the
failure NamedDecl for a given usage is also duplicated, once when
creating failures and again when identify usages. There are currently
two ways to a failed NamedDecl from a usage: use the canonical decl or
use the overridden method. With new methods about to be added, a cleanup
was in order.
The data flow is simplified as follows:
* The visitor always forwards NamedDecls to addUsage(NamedDecl).
* addUsage(NamedDecl) determines the failed NamedDecl and determines
potential new names based on that failure. Usages are registered using
addUsage(NamingCheckId).
* addUsage(NamingCheckId) is now protected and its single responsibility
is maintaining the integrity of the failure/usage map.
Some functions allow a null SourceManager, no SourceManager, or a
SourceManager in an inconsistent argument position. Since SourceManager
is generally not null and it doesn't make sense to apply renaming
without one, these inconsistencies are now gone.
Although the identifier-naming.cpp lit test expected macro arguments not
to be renamed, the code seemed to already allow it. The code was simply
not being exercised because a SourceManager argument wasn't being
provided. With this change, renaming of macro arguments that expand to
renamable decls is permitted.
Typedef rename were not properly handled when typedef were used behind
pointer, or as a part of function type. Additionally because entire
function were passed as an source-range, when function started with
macro, such change were not marked for a fix.
Removed workaround and used proper TypedefTypeLoc instead.
Fixes#55156, #54699
Refactor RenamerClangTidyCheck to achieve better performance
by removing object copies, duplicated function calls and by
using RecursiveASTVisitor.
Measured -72% execution time on bugprone-reserved-identifier.
Reviewed By: njames93
Differential Revision: https://reviews.llvm.org/D149723
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
This patch replaces those occurrences of NoneType that would trigger
an error if the definition of NoneType were missing in None.h.
To keep this patch focused, I am deliberately not replacing None with
std::nullopt in this patch or updating comments. They will be
addressed in subsequent patches.
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
Differential Revision: https://reviews.llvm.org/D138539
This fixes a problem where __va_list_tag was not correctly imported,
possibly leading to multiple definitions with different types.
This adds __va_list_tag to it's proper scope, so that the ASTImporter
can find it.
Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>
Differential Revision: https://reviews.llvm.org/D136886
Run clang-tidy on all source files under `clang-tools-extra/clang-tidy`
with `-header-filter=clang-tidy.*` and make suggested corrections.
Differential Revision: https://reviews.llvm.org/D112864
Rename methods to clearly signal when they only deal with ASCII,
simplify the parsing of identifier, and use start/continue instead of
head/body for consistency with Unicode terminology.
The patch adjusts the existing `llvm::DenseMap<unsigned, T>` and
`llvm::DenseSet<unsigned>` objects that store source locations, so
that they use `SourceLocation` directly instead of `unsigned`.
This patch relies on the `DenseMapInfo` trait added in D89719.
It also replaces the construction of `SourceLocation` objects from
the constants -1 and -2 with calls to the trait's methods `getEmptyKey`
and `getTombstoneKey` where appropriate.
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D69840
Prevent fixes being displayed if usages are found in the scratch buffer.
See [[ https://bugs.llvm.org/show_bug.cgi?id=46219 | Fix-It hints are being generated in the ScratchBuffer ]].
It may be wise down the line to put in a general fix in clang-tidy to prevent ScratchBuffer replacements being applied, but for now this will help.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D82162
This changes the behavious of `RenamerClangTidyCheck` based checks by grouping declarations of the same thing into 1 warning where it is first declared.
This cleans up clang-tidy output and prevents issues where 1 fix-it couldn't be applied, yet all other warnings(and fix-its) for the same declaration would be applied.
The old behaviour of forward declaring a class without defining it isn't affected, i.e. no warnings will be emitted for that case.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D82059
Summary:
Sometimes in templated code Member references are reported as `DependentScopeMemberExpr` because that's what the standard dictates, however in many trivial cases it is easy to resolve the reference to its actual Member.
Take this code:
```
template<typename T>
class A{
int value;
A& operator=(const A& Other){
value = Other.value;
this->value = Other.value;
return *this;
}
};
```
When ran with `clang-tidy file.cpp -checks=readability-identifier-naming --config="{CheckOptions: [{key: readability-identifier-naming.MemberPrefix, value: m_}]}" -fix`
Current behaviour:
```
template<typename T>
class A{
int m_value;
A& operator=(const A& Other){
m_value = Other.value;
this->value = Other.value;
return *this;
}
};
```
As `this->value` and `Other.value` are Dependent they are ignored when creating the fix-its, however this can easily be resolved.
Proposed behaviour:
```
template<typename T>
class A{
int m_value;
A& operator=(const A& Other){
m_value = Other.m_value;
this->m_value = Other.m_value;
return *this;
}
};
```
Reviewers: aaron.ballman, JonasToth, alexfh, hokein, gribozavr2
Reviewed By: aaron.ballman
Subscribers: merge_guards_bot, xazax.hun, cfe-commits
Tags: #clang, #clang-tools-extra
Differential Revision: https://reviews.llvm.org/D73052
This reverts commit 27e3671ff49b72640f89c34a415412e400503442.
This was an accidental push, and the author requested a revert on IRC as
their local branch is in a bad state.
Summary:
Typically most main functions have the signature:
```
int main(int argc, char *argv[])
```
To stick with convention when renaming parameters we should ignore the `argc` and `argv` names even if the parameter style says they should be renamed. This patch addresses this by checking all ParmVarDecls if they form part of a function with a signature that matches main `int name(int argc, char * argv[], (optional char *env[]))`
Reviewers: aaron.ballman, JonasToth, alexfh, hokein
Reviewed By: aaron.ballman
Subscribers: Mordante, merge_guards_bot, xazax.hun, kristof.beyls, cfe-commits
Tags: #clang, #clang-tools-extra
Differential Revision: https://reviews.llvm.org/D73098
Before this patch, readability-identifier-naming contained a significant amount
of logic for (a) checking the style of identifiers, followed by (b) renaming/
applying fix-its. This patch factors out (b) into a separate base class so that
it can be reused by other checks that want to do renaming. This also cleans up
readability-identifier-naming significantly, since now it only needs to be
concerned with the interesting details of (a).
