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
C++17's CTAD obsoletes `makeMatcher` (and many `make*` functions like
it).
The deduction guide is written out explicitly to avoid
`-Wctad-maybe-unsupported` warnings.
Introduce a type alias for the commonly used `std::pair<FileID,
unsigned>` to improve code readability, and make it easier for future
updates (64-bit source locations).
These are identified by misc-include-cleaner. I've filtered out those
that break builds. Also, I'm staying away from llvm-config.h,
config.h, and Compiler.h, which likely cause platform- or
compiler-specific build failures.
Use `getParenOrBraceRange()` to get the location of the opening paren or
braces instead of searching backwards from the first argument.
For implicit construction, get the range surrounding the first and last
arguments.
Since `raw_string_ostream` doesn't own the string buffer, it is
desirable (in terms of memory safety) for users to directly reference
the string buffer rather than use `raw_string_ostream::str()`.
Work towards TODO comment to remove `raw_string_ostream::str()`.
When there is `>>` in source from the right brackets of a nested
template, the end location of the inner template points into a scratch
space with a single `>` token. This prevents the lexer from seeing the
`>>` token in the original source.
However, this causes the range to appear to be partially in a macro, and
is problematic if we are trying to avoid ranges with any macro
expansions.
This change detects these split tokens in token ranges, converting it to the
corresponding character range without the expansion.
This patch replaces uses of StringRef::{starts,ends}with with
StringRef::{starts,ends}_with for consistency with
std::{string,string_view}::{starts,ends}_with in C++20.
I'm planning to deprecate and eventually remove
StringRef::{starts,ends}with.
Previously, where `name` was applied to a template-specialization TypeLoc, it
returned the entire specialization (name, brackets, args) rather than just the
name identifier. With this change, exactly the name token is selected.
Differential Revision: https://reviews.llvm.org/D158771
With the addition of `getFileRange`, we rename `getRangeForEdit` as
`getFileRangeForEdit` for consistency in the API.
Depends on D141634
Differential Revision: https://reviews.llvm.org/D141636
Add a `getFileRange` function alongside the existing `getRangeForEdit`
as a way to get a contiguous range within a single file (similar to
`getRangeForEdit`) but without the restriction that it cannot be in a
system header.
This can be used where a tool may want to use the range to extract the
source text. In such cases, we don't want to restrict this from
pulling from system headers.
Differential Revision: https://reviews.llvm.org/D141634
This commit resolves the FIXME around the behavior of
`Lexer::makeFileCharRange` that `getRangeForEdit` inherits around
source locations in macro expansions.
We add a flag to `getRangeForEdit` that allows a caller to disable the
behavior, and instead uses the spelling location instead, with checks
to ensure that the source locations are not within a macro definition.
Differential Revision: https://reviews.llvm.org/D139676
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
Right now we can only add a single warning, notes are not possible.
Apparently some provisions were made to allow notes, but they were never
propagated all the way to the diagnostics.
Differential Revision: https://reviews.llvm.org/D128807
Given that we provide an EditGenerator edit(ASTEdit), we can't ever be
sure that the user won't give us an empty replacement.
Differential Revision: https://reviews.llvm.org/D128887
Support `TransformerResult<void>` in the consumer callback, which
allows generic code to more naturally use the `Transformer` interface
(instead of needing to specialize on `void`).
This also delete the specialization that existed within `Transformer`
itself, instead replacing it with an `std::function` adapter.
Reviewed By: ymandel
Differential Revision: https://reviews.llvm.org/D122499
Change RewriteRule from holding an `Explanation` to being able to generate
arbitrary metadata. Where TransformerClangTidyCheck was interested in a string
description for the diagnostic, other tools may be interested in richer metadata
at a higher level of abstraction than at the edit level (which is currently
available as ASTEdit::Metadata).
Reviewed By: ymandel
Differential Revision: https://reviews.llvm.org/D120360
Change RewriteRule from holding an `Explanation` to being able to generate
arbitrary metadata. Where TransformerClangTidyCheck was interested in a string
description for the diagnostic, other tools may be interested in richer metadata
at a higher level of abstraction than at the edit level (which is currently
available as ASTEdit::Metadata).
Reviewed By: ymandel
Differential Revision: https://reviews.llvm.org/D120360
Previously, Transformer would invoke the consumer once per file modified per
match, in addition to any errors encountered. The consumer is not aware of which
AtomicChanges come from any particular match. It is unclear which sets of edits
may be related or whether an error invalidates any previously emitted changes.
Modify the signature of the consumer to accept a set of changes. This keeps
related changes (i.e. all edits from a single match) together, and clarifies
that errors don't produce partial changes.
Reviewed By: ymandel
Differential Revision: https://reviews.llvm.org/D119745
This patch adds a `buildAccess` function, which constructs a string with the
proper operator to use based on the expression's form and type. It also adds two
predicates related to smart pointers, which are needed by `buildAccess` but are
also of general value.
We deprecate `buildDot` and `buildArrow` in favor of the more general
`buildAccess`. These will be removed in a future patch.
Differential Revision: https://reviews.llvm.org/D116377
Adds `selectBound`, a `Stencil` combinator that allows the user to supply multiple alternative cases, discriminated by bound node IDs.
Differential Revision: https://reviews.llvm.org/D111708
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.
Currently, `access` doesn't recognize a dereferenced smart pointer. So,
`access(e, "field")` where `e = *x`, yields:
* `x->field`, for normal-pointer x,
* `(*x).field`, for smart-pointer x.
This patch normalizes handling of smart pointer to match normal pointer, when
the smart pointer type supports `->`.
Differential Revision: https://reviews.llvm.org/D104390
Currently, the implementation combines OOP and overloads, using a template to
tie the two together. In practice, this has proven confusing with no
benefits. This patch simplifies the code to use standard OOP design (a
collection of classes deriving from an interface).
Differential Revision: https://reviews.llvm.org/D104317
This patch changes the default range used to anchor the include insertion to use
an expansion loc. This ensures that the location is valid, when the user relies
on the default range.
Driveby: extend a FIXME for a problem that was emphasized by this change; fix some spellings.
Differential Revision: https://reviews.llvm.org/D93703
Stencils `maybeDeref` and `maybeAddressOf` are designed to handle nodes that may
be pointers. Currently, they only handle native pointers. This patch extends the
support to recognize smart pointers and handle them as well.
Differential Revision: https://reviews.llvm.org/D93637
A number of declarations were leftover after the move from `clang::tooling` to
`clang::transformer`. This patch removes those declarations and upgrades the
handful of references to the deprecated declarations.
Differential Revision: https://reviews.llvm.org/D92340
Currently, `node` only includes the semicolon for (some) statements. However,
declarations have the same issue of (potentially) trailing semicolons, so `node`
should behave the same for them.
Differential Revision: https://reviews.llvm.org/D91872