This rename was made as part of
https://github.com/llvm/llvm-project/pull/147835 in order to ease
rebasing the PR, and give a nice window for other patches to get rebased
as well.
It has been a while already, so lets go ahead and rename it back.
A previous change to support HLSL strict availability had an unintended
side effect of silencing deprecation warnings. This change fixes that
issue and adds test coverage.
Fixes#132978
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
Do not warn on deprecated member used in an implicit definition (such as a defaulted special member function).
Co-authored-by: Corentin Jabot <corentinjabot@gmail.com>
Fixes#147293
This undoes part of 3e4e3b17c14c15c23c0ed18ca9165b42b1b13ae3 which added
the "Omitting a deprecated constant is ok; it should never materialize."
logic.
That seems wrong: deprecated means the enumerator is likely to be
removed in future versions, not that it cannot materialize.
Also move warnings about the use of deprecated enumerators in switch cases
behind a separate flag, -Wdeprecated-switch-case, for users who wish to
handle such enums explicitly and suppress the warning.
There are some limitations.
Because we only know which partial specialization to refer to when
instantiating, and because we can't instantiate the class before we
require a complete type, we can only use the partial specialization once
we have a complete class.
Similarly, because we don't know if a class is ever going to be
complete, we always warn on availability of the primary. Therefore, we
only warn for the partial specialization if we did not warn on the
primary.
I considered alternatives to address that second limitation:
- Delay warnings to the end of the TU
- Tracking where each availability attribute originally comes from.
However, both of these have drawbacks, and the use case is probably less
motivated than wanting to deprecate the use of a specific
specialization.
Fixes#44496
At present, `__builtin_available` is really restrictive with its use.
Overall, this seems like a good thing, since the analyses behind it are
not very expensive.
That said, it's very straightforward to support these two cases:
```
if ((__builtin_available(foo, *))) {
// ...
}
```
and
```
if (!__builtin_available(foo, *)) {
// ...
} else {
// ...
}
```
Seems nice to do so.
Apple's API_AVAILABLE macro has its own notion of platform names which
are supported by \_\_API_AVAILABLE_PLATFORM_<name> macros. They don't
follow a consistent naming convention, but there's at least one that
matches a valid availability attribute platform name. Instead of
lowercasing the source spelling name, search for a defined macro and use
that in the fix-it.
This patch adds an assertion in the DiagnoseDeclAvailabilit() function
to ensure that the expected availability attribute is not null before
they are passed to hasMatchingEnvironmentOrNone() to prevent potential
null pointer dereferences and improve the robustness of the availability
diagnostics process.
Implements HLSL availability diagnostics' strict mode.
HLSL availability diagnostics emits errors or warning when unavailable
shader APIs are used. Unavailable shader APIs are APIs that are exposed
in HLSL code but are not available in the target shader stage or shader
model version.
In the strict mode the compiler emits an error when an unavailable API
is found in any function regardless of whether it is reachable from the
shader entry point or not. This mode is enabled by
``-fhlsl-strict-availability``.
See HLSL Availability Diagnostics design doc
[here](https://github.com/llvm/llvm-project/blob/main/clang/docs/HLSL/AvailabilityDiagnostics.rst)
for more details.
Fixes#90096
The availability attributes are stored on the function declarations. The
code was looking for them in the function template declarations. This
resulted in spuriously diagnosing (non-strict) availablity issues in
contexts that are not available.
Co-authored-by: Gabor Horvath <gaborh@apple.com>
Implements HLSL availability diagnostics' default and relaxed mode.
HLSL availability diagnostics emits errors or warning when unavailable
shader APIs are used. Unavailable shader APIs are APIs that are exposed
in HLSL code but are not available in the target shader stage or shader
model version.
In the default mode the compiler emits an error when an unavailable API
is found in a code that is reachable from the shader entry point
function. In the future this check will also extended to exported
library functions (#92073). The relaxed diagnostic mode is the same
except the compiler emits a warning. This mode is enabled by
``-Wno-error=hlsl-availability``.
See HLSL Availability Diagnostics design doc
[here](https://github.com/llvm/llvm-project/blob/main/clang/docs/HLSL/AvailabilityDiagnostics.rst)
for more details.
Fixes#90095
Availability diagnostic in instantiated template functions was
intentionally skipped in the original
[commit](5cd57177a5)
years ago with a FIXME note.
I ran into this when working on diagnostics for HLSL. When I remove the
skip, it seems to be working just fine outputting expected messages. So,
unless I am missing something, I would keep it enabled and use it for
checking availability in HLSL templates as well.
Add `environment` parameter to Clang availability attribute. The allowed
values for this parameter are a subset of values allowed in the
`llvm::Triple` environment component. If the `environment` parameters is
present, the declared availability attribute applies only to targets
with the same platform and environment.
This new parameter will be initially used for annotating HLSL functions
for the `shadermodel` platform because in HLSL built-in function
availability can depend not just on the shader model version (mapped to
`llvm::Triple::OSType`) but also on the target shader stage (mapped to
`llvm::Triple::EnvironmentType`). See example in #89802 and
microsoft/hlsl-specs#204 for more details.
The environment parameter is currently supported only for HLSL.
Fixes#89802
When the top of the instantiation stack is in user code.
The goal of this PR is to allow deprecation of some char_traits
specializations in libc++ as done in https://reviews.llvm.org/D157058
which was later reverted by
https://github.com/llvm/llvm-project/pull/66153#issuecomment-1719578384
as Clang never emitted the libc++ warnings.
Because Clang likes to eagerly instantiate, we can look for the location
of the top of the instantiation stack, and emit a warning if that
location is in user code.
The warning emission is forced by temporarily instructing the diag
engine not to silence warning in system headers.
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
Some HLSL functionality is gated on the target shader model version.
Enabling the use of availability markup allows us to diagnose
availability issues easily in the frontend.
Reviewed By: erichkeane
Differential Revision: https://reviews.llvm.org/D134067
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.
We now make up a TypeLoc for the class receiver to simplify visiting,
notably for indexing, availability, and clangd.
Differential Revision: https://reviews.llvm.org/D101645
This fixes both https://bugs.llvm.org/show_bug.cgi?id=50309 and https://bugs.llvm.org/show_bug.cgi?id=50310.
Previously, lambdas inside functions would mark their own bodies for later analysis when encountering a potentially unavailable decl, without taking into consideration that the entire lambda itself might be correctly guarded inside an @available check. The same applied to inner class member functions. Blocks happened to work as expected already, since Sema::getEnclosingFunction() skips through block scopes.
This patch instead simply and conservatively marks the entire outermost function scope for search, and removes some special-case logic that prevented DiagnoseUnguardedAvailabilityViolations from traversing down into lambdas and nested functions. This correctly accounts for arbitrarily nested lambdas, inner classes, and blocks that may be inside appropriate @available checks at any ancestor level. It also treats all potential availability violations inside functions consistently, without being overly sensitive to the current DeclContext, which previously caused issues where e.g. nested struct members were warned about twice.
DiagnoseUnguardedAvailabilityViolations now has more work to do in some cases, particularly in functions with many (possibly deeply) nested lambdas and classes, but the big-O is the same, and the simplicity of the approach and the fact that it fixes at least two bugs feels like a strong win.
Differential Revision: https://reviews.llvm.org/D102338
This is how it should've been and brings it more in line with
std::string_view. There should be no functional change here.
This is mostly mechanical from a custom clang-tidy check, with a lot of
manual fixups. It uncovers a lot of minor inefficiencies.
This doesn't actually modify StringRef yet, I'll do that in a follow-up.
Reduces compile time of SemaDeclAttr.cpp down to 28s from 50s. The new
TU does a few RecursiveASTVisitor instantiations, so it takes 30s.
Reviewed By: rsmith
Differential Revision: https://reviews.llvm.org/D73385