1576 Commits

Author SHA1 Message Date
Mariya Podchishchaeva
aced81c0a5
[C23] Implement N3018: The constexpr specifier for object definitions (#73099)
The implementation mostly reuses C++ code paths where possible,
including narrowing check in order to provide diagnostic messages in
case initializer for constexpr variable is not exactly representable in
target type.

The following won't work due to lack of support for other features:
- Diagnosing of underspecified declarations involving constexpr
- Constexpr attached to compound literals

Also due to lack of support for char8_t some of examples with utf-8
strings don't work properly.

Fixes https://github.com/llvm/llvm-project/issues/64742
2024-03-06 09:46:35 +01:00
Sirraide
d23ef9ef36
[Clang] [Sema] Handle placeholders in '.*' expressions (#83103)
When analysing whether we should handle a binary expression as an
overloaded operator call or a builtin operator, we were calling
`checkPlaceholderForOverload()`, which takes care of any placeholders
that are not overload sets—which would usually make sense since those
need to be handled as part of overload resolution.

Unfortunately, we were also doing that for `.*`, which is not
overloadable, and then proceeding to create a builtin operator anyway,
which would crash if the RHS happened to be an unresolved overload set
(due hitting an assertion in `CreateBuiltinBinOp()`—specifically, in one
of its callees—in the `.*` case that makes sure its arguments aren’t
placeholders).

This pr instead makes it so we check for *all* placeholders early if the
operator is `.*`.

It’s worth noting that,
1. In the `.*` case, we now additionally also check for *any*
placeholders (not just non-overload-sets) in the LHS; this shouldn’t
make a difference, however—at least I couldn’t think of a way to trigger
the assertion with an overload set as the LHS of `.*`; it is worth
noting that the assertion in question would also complain if the LHS
happened to be of placeholder type, though.
2. There is another case in which we also don’t perform overload
resolution—namely `=` if the LHS is not of class or enumeration type
after handling non-overload-set placeholders—as in the `.*` case, but
similarly to 1., I first couldn’t think of a way of getting this case to
crash, and secondly, `CreateBuiltinBinOp()` doesn’t seem to care about
placeholders in the LHS or RHS in the `=` case (from what I can tell,
it, or rather one of its callees, only checks that the LHS is not a
pseudo-object type, but those will have already been handled by the call
to `checkPlaceholderForOverload()` by the time we get to this function),
so I don’t think this case suffers from the same problem.

This fixes #53815.

---------

Co-authored-by: Aaron Ballman <aaron@aaronballman.com>
2024-02-27 14:19:44 -05:00
Farzon Lotfi
a870a48c09
[HLSL] Fix casting asserts (#82827)
There are two issues here. first `ICK_Floating_Integral` were always
defaulting to `CK_FloatingToIntegral` for vectors regardless of
direction of cast. Check was scalar only so added a vec float check to
the conditional.

Second issue was float to int casts were resolving to
ICK_Integral_Promotion when they need to be resolving to
CK_FloatingToIntegral. This was fixed by changing the ordering of
conversion checks.

This fixes #82826
2024-02-26 16:12:13 -06:00
Chris B
5c57fd717d
[HLSL] Vector standard conversions (#71098)
HLSL supports vector truncation and element conversions as part of
standard conversion sequences. The vector truncation conversion is a C++
second conversion in the conversion sequence. If a vector truncation is
in a conversion sequence an element conversion may occur after it before
the standard C++ third conversion.

Vector element conversions can be boolean conversions, floating point or
integral conversions or promotions.

[HLSL Draft
Specification](https://microsoft.github.io/hlsl-specs/specs/hlsl.pdf)

---------

Co-authored-by: Aaron Ballman <aaron@aaronballman.com>
2024-02-15 14:58:06 -06:00
Chris Bieneman
a1155f68f5 [NFC] Clang-format const array declarations
This just updates indentation of constant array declarations to be
style conformant.
2024-02-15 13:16:21 -06:00
Vlad Serebrennikov
dfbe2bca1d
[clang][NFC] Refactor Sema::TemplateDeductionResult (#81398)
This patch converts `Sema::TemplateDeductionResult` into a scoped enum
in namespace scope, making it eligible for forward declaring. This is
useful in certain contexts, such as `preferred_type` annotations on
bit-fields.
2024-02-12 21:27:58 +04:00
Sirraide
52bf531630
[Clang][Sema] Fix out-of-bounds access (#80978)
Trying to compile a C-style variadic member function with an explicit
object parameter was crashing in Sema because of an out-of-bounds
access.

This fixes #80971.
2024-02-07 15:12:15 +01:00
PiJoules
5b780c8c6c
Diagnose invalid fixed point conversion (#80763) 2024-02-06 11:29:30 -08:00
Younan Zhang
141de74959
[clang][Sema] Populate function template depth at AddTemplateOverloadCandidate (#80395)
This is yet another one-line patch to fix crashes on constraint
substitution.

```cpp
template <class, class> struct formatter;

template <class, class> struct basic_format_context {};

template <typename CharType>
concept has_format_function = format(basic_format_context<CharType, CharType>());

template <typename ValueType, typename CharType>
  requires has_format_function<CharType>
struct formatter<ValueType, CharType> {
  template <typename OutputIt>
  CharType format(basic_format_context<OutputIt, CharType>);
};
```

In this case, we would build up a `RecoveryExpr` for a call within a
constraint expression due to the absence of viable functions. The
heuristic algorithm attempted to find such a function inside of a
ClassTemplatePartialSpecialization, from which we started to substitute
its requires-expression, and it succeeded with a FunctionTemplate such
that

1) It has only one parameter, which is dependent.
2) The only one parameter depends on two template parameters. They are,
in canonical form, `<template-parameter-1-0>` and
`<template-parameter-0-1>` respectively.

Before we emit an error, we still want to recover the most viable
functions. This goes downhill to deducing template parameters against
its arguments, where we would collect the argument type with the same
depth as the parameter type into a Deduced set. The size of the set is
presumed to be that of function template parameters, which is 1 in this
case. However, since we haven't yet properly set the template depth
before the dance, we'll end up putting the type for
`<template-parameter-0-1>` to the second position of Deduced set, which
is unfortunately an access violation!

The bug seems to appear since clang 12.0.

This fixes [the
case](https://github.com/llvm/llvm-project/issues/58548#issuecomment-1287935336).
2024-02-03 16:14:48 +08:00
Tianlan Zhou
ee01a2c399
[clang] static operators should evaluate object argument (reland) (#80108)
This re-applies 30155fc0 with a fix for clangd.

### Description

clang don't evaluate the object argument of `static operator()` and
`static operator[]` currently, for example:

```cpp
#include <iostream>

struct Foo {
    static int operator()(int x, int y) {
        std::cout << "Foo::operator()" << std::endl;
        return x + y;
    }
    static int operator[](int x, int y) {
        std::cout << "Foo::operator[]" << std::endl;
        return x + y;
    }
};
Foo getFoo() {
    std::cout << "getFoo()" << std::endl;
    return {};
}
int main() {
    std::cout << getFoo()(1, 2) << std::endl;
    std::cout << getFoo()[1, 2] << std::endl;
}
```

`getFoo()` is expected to be called, but clang don't call it currently
(17.0.6). This PR fixes this issue.

Fixes #67976, reland #68485.

### Walkthrough

- **clang/lib/Sema/SemaOverload.cpp**
- **`Sema::CreateOverloadedArraySubscriptExpr` &
`Sema::BuildCallToObjectOfClassType`**
Previously clang generate `CallExpr` for static operators, ignoring the
object argument. In this PR `CXXOperatorCallExpr` is generated for
static operators instead, with the object argument as the first
argument.
  - **`TryObjectArgumentInitialization`**
`const` / `volatile` objects are allowed for static methods, so that we
can call static operators on them.
- **clang/lib/CodeGen/CGExpr.cpp**
  - **`CodeGenFunction::EmitCall`**
CodeGen changes for `CXXOperatorCallExpr` with static operators: emit
and ignore the object argument first, then emit the operator call.
- **clang/lib/AST/ExprConstant.cpp**
  - **`‎ExprEvaluatorBase::handleCallExpr‎`**
Evaluation of static operators in constexpr also need some small changes
to work, so that the arguments won't be out of position.
- **clang/lib/Sema/SemaChecking.cpp**
  - **`Sema::CheckFunctionCall`**
Code for argument checking also need to be modify, or it will fail the
test `clang/test/SemaCXX/overloaded-operator-decl.cpp`.
- **clang-tools-extra/clangd/InlayHints.cpp**
  - **`InlayHintVisitor::VisitCallExpr`**
Now that the `CXXOperatorCallExpr` for static operators also have object
argument, we should also take care of this situation in clangd.

### Tests

- **Added:**
    - **clang/test/AST/ast-dump-static-operators.cpp**
      Verify the AST generated for static operators.
    - **clang/test/SemaCXX/cxx2b-static-operator.cpp**
Static operators should be able to be called on const / volatile
objects.
- **Modified:**
    - **clang/test/CodeGenCXX/cxx2b-static-call-operator.cpp**
    - **clang/test/CodeGenCXX/cxx2b-static-subscript-operator.cpp**
      Matching the new CodeGen.

### Documentation

- **clang/docs/ReleaseNotes.rst**
  Update release notes.

---------

Co-authored-by: Shafik Yaghmour <shafik@users.noreply.github.com>
Co-authored-by: cor3ntin <corentinjabot@gmail.com>
Co-authored-by: Aaron Ballman <aaron@aaronballman.com>
2024-01-31 15:27:06 +08:00
Aaron Ballman
201eb2b577 Revert "[clang] static operators should evaluate object argument (#68485)"
This reverts commit 30155fc0ef4fbdce2d79434aaae8d58b2fabb20a.

It seems to have broken some tests in clangd:
http://45.33.8.238/linux/129484/step_9.txt
2024-01-30 13:38:18 -05:00
Tianlan Zhou
30155fc0ef
[clang] static operators should evaluate object argument (#68485)
### Description

clang don't evaluate the object argument of `static operator()` and
`static operator[]` currently, for example:

```cpp
#include <iostream>

struct Foo {
    static int operator()(int x, int y) {
        std::cout << "Foo::operator()" << std::endl;
        return x + y;
    }
    static int operator[](int x, int y) {
        std::cout << "Foo::operator[]" << std::endl;
        return x + y;
    }
};
Foo getFoo() {
    std::cout << "getFoo()" << std::endl;
    return {};
}
int main() {
    std::cout << getFoo()(1, 2) << std::endl;
    std::cout << getFoo()[1, 2] << std::endl;
}
```

`getFoo()` is expected to be called, but clang don't call it currently
(17.0.2). This PR fixes this issue.

Fixes #67976.

### Walkthrough

- **clang/lib/Sema/SemaOverload.cpp**
- **`Sema::CreateOverloadedArraySubscriptExpr` &
`Sema::BuildCallToObjectOfClassType`**
Previously clang generate `CallExpr` for static operators, ignoring the
object argument. In this PR `CXXOperatorCallExpr` is generated for
static operators instead, with the object argument as the first
argument.
  - **`TryObjectArgumentInitialization`**
`const` / `volatile` objects are allowed for static methods, so that we
can call static operators on them.
- **clang/lib/CodeGen/CGExpr.cpp**
  - **`CodeGenFunction::EmitCall`**
CodeGen changes for `CXXOperatorCallExpr` with static operators: emit
and ignore the object argument first, then emit the operator call.
- **clang/lib/AST/ExprConstant.cpp**
  - **`‎ExprEvaluatorBase::handleCallExpr‎`**
Evaluation of static operators in constexpr also need some small changes
to work, so that the arguments won't be out of position.
- **clang/lib/Sema/SemaChecking.cpp**
  - **`Sema::CheckFunctionCall`**
Code for argument checking also need to be modify, or it will fail the
test `clang/test/SemaCXX/overloaded-operator-decl.cpp`.

### Tests

- **Added:**
    - **clang/test/AST/ast-dump-static-operators.cpp**
      Verify the AST generated for static operators.
    - **clang/test/SemaCXX/cxx2b-static-operator.cpp**
Static operators should be able to be called on const / volatile
objects.
- **Modified:**
    - **clang/test/CodeGenCXX/cxx2b-static-call-operator.cpp**
    - **clang/test/CodeGenCXX/cxx2b-static-subscript-operator.cpp**
      Matching the new CodeGen.

### Documentation

- **clang/docs/ReleaseNotes.rst**
  Update release notes.

---------

Co-authored-by: Shafik Yaghmour <shafik@users.noreply.github.com>
Co-authored-by: cor3ntin <corentinjabot@gmail.com>
Co-authored-by: Aaron Ballman <aaron@aaronballman.com>
2024-01-30 13:09:05 -05:00
Alexander Kornienko
6e4930c675 Revert "[SemaCXX] Implement CWG2137 (list-initialization from objects of the same type) (#77768)"
This reverts commit 924701311aa79180e86ad8ce43d253f27d25ec7d. Causes compilation
errors on valid code, see
https://github.com/llvm/llvm-project/pull/77768#issuecomment-1908062472.
2024-01-24 21:42:38 +01:00
Mariya Podchishchaeva
11d1310b57
[clang] Fix assertion failure with deleted overloaded unary operators (#78316)
When emitting notes related to wrong number of arguments do not consider
object argument.

Fixes https://github.com/llvm/llvm-project/issues/78314
2024-01-22 10:06:26 +01:00
Andrey Ali Khan Bolshakov
5518a9d767
[c++20] P1907R1: Support for generalized non-type template arguments of scalar type. (#78041)
Previously committed as 9e08e51a20d0d2b1c5724bb17e969d036fced4cd, and
reverted because a dependency commit was reverted, then committed again
as 4b574008aef5a7235c1f894ab065fe300d26e786 and reverted again because
"dependency commit" 5a391d38ac6c561ba908334d427f26124ed9132e was
reverted. But it doesn't seem that 5a391d38ac6c was a real dependency
for this.

This commit incorporates 4b574008aef5a7235c1f894ab065fe300d26e786 and
18e093faf726d15f210ab4917142beec51848258 by Richard Smith (@zygoloid),
with some minor fixes, most notably:

- `UncommonValue` renamed to `StructuralValue`

- `VK_PRValue` instead of `VK_RValue` as default kind in lvalue and
member pointer handling branch in
`BuildExpressionFromNonTypeTemplateArgumentValue`;

- handling of `StructuralValue` in `IsTypeDeclaredInsideVisitor`;

- filling in `SugaredConverted` along with `CanonicalConverted`
parameter in `Sema::CheckTemplateArgument`;

- minor cleanup in
`TemplateInstantiator::transformNonTypeTemplateParmRef`;

- `TemplateArgument` constructors refactored;

- `ODRHash` calculation for `UncommonValue`;

- USR generation for `UncommonValue`;

- more correct MS compatibility mangling algorithm (tested on MSVC ver.
19.35; toolset ver. 143);

- IR emitting fixed on using a subobject as a template argument when the
corresponding template parameter is used in an lvalue context;

- `noundef` attribute and opaque pointers in `template-arguments` test;

- analysis for C++17 mode is turned off for templates in
`warn-bool-conversion` test; in C++17 and C++20 mode, array reference
used as a template argument of pointer type produces template argument
of UncommonValue type, and
`BuildExpressionFromNonTypeTemplateArgumentValue` makes
`OpaqueValueExpr` for it, and `DiagnoseAlwaysNonNullPointer` cannot see
through it; despite of "These cases should not warn" comment, I'm not
sure about correct behavior; I'd expect a suggestion to replace `if` by
`if constexpr`;

- `temp.arg.nontype/p1.cpp` and `dr18xx.cpp` tests fixed.
2024-01-21 21:28:57 +01:00
Mital Ashok
924701311a
[SemaCXX] Implement CWG2137 (list-initialization from objects of the same type) (#77768)
Closes #77638, #24186

Rebased from <https://reviews.llvm.org/D156032>, see there for more
information.

Implements wording change in [CWG2137](https://wg21.link/CWG2137) in the
first commit.

This also implements an approach to [CWG2311](https://wg21.link/CWG2311)
in the second commit, because too much code that relies on `T{ T_prvalue}` 
being an elision would break. Because that issue is still open and
the CWG issue doesn't provide wording to fix the issue, there may be
different behaviours on other compilers.
2024-01-19 21:10:51 +01:00
cor3ntin
e90e43fb9c
[Clang][NFC] Rename CXXMethodDecl::isPure -> is VirtualPure (#78463)
To avoid any possible confusion with the notion of pure function and the
gnu::pure attribute.
2024-01-18 15:30:58 +01:00
cor3ntin
c58bc24fcf
[Clang] Only compare template params of potential overload after checking their decl context (#78139)
Fixes a regression from 69066ab3 in which we compared the template lists
of potential overloads before checkings their declaration contexts.

This would cause a crash when doing constraint substitution as part of
that template check, because we would try to refer to not yet
instantiated entities (the underlying cause is unclear).

This patch reorders (again) when we look at template parameter so we
don't do it when checkings friends in different lexical contexts.

Fixes #77953
Fixes #78101
2024-01-16 00:56:42 +01:00
Sander de Smalen
8e7f073eb4
[Clang][AArch64] Change SME attributes for shared/new/preserved state. (#76971)
This patch replaces the `__arm_new_za`, `__arm_shared_za` and
`__arm_preserves_za` attributes in favour of:
* `__arm_new("za")`
* `__arm_in("za")`
* `__arm_out("za")`
* `__arm_inout("za")`
* `__arm_preserves("za")`

As described in https://github.com/ARM-software/acle/pull/276.

One change is that `__arm_in/out/inout/preserves(S)` are all mutually
exclusive, whereas previously it was fine to write `__arm_shared_za
__arm_preserves_za`. This case is now represented with `__arm_in("za")`.

The current implementation uses the same LLVM attributes under the hood,
since `__arm_in/out/inout` are all variations of "shared ZA", so can use
the existing `aarch64_pstate_za_shared` attribute in LLVM.

#77941 will add support for the new "zt0" state as introduced
with SME2.
2024-01-15 09:41:32 +00:00
Utkarsh Saxena
460ff58f62
[clang] Reapply Handle templated operators with reversed arguments (#72213)
Re-applies https://github.com/llvm/llvm-project/pull/69595 with extra
[diff](79181efd0d)
### New changes

Further relax ambiguities with a warning for member operators of a
template class (primary templates of such ops do not match). Eg:
```cpp
template <class T>
struct S {
    template <typename OtherT>
    bool operator==(const OtherT &rhs); 
};
struct A : S<int> {};
struct B : S<bool> {};
bool x = A{} == B{}; // accepted with a warning.
```

This is important for making llvm build using previous clang versions in
C++20 mode (eg: this makes the commit
e558be51bab051d1471d92e967f8a2aecc13567a keep working with a warning
instead of an error).

### Description from https://github.com/llvm/llvm-project/pull/69595

https://github.com/llvm/llvm-project/pull/68999 correctly computed
conversion sequence for reversed args to a template operator. This was a
breaking change as code, previously accepted in C++17, starts to break
in C++20.

Example:
```cpp
struct P {};
template<class S> bool operator==(const P&, const S &);

struct A : public P {};
struct B : public P {};
bool check(A a, B b) { return a == b; }  // This is now ambiguous in C++20.
```

In order to minimise widespread breakages, as a clang extension, we had
previously accepted such ambiguities with a warning
(`-Wambiguous-reversed-operator`) for non-template operators. Due to the
same reasons, we extend this relaxation for template operators.

Fixes https://github.com/llvm/llvm-project/issues/53954
2024-01-12 15:03:01 +01:00
Andrey Ali Khan Bolshakov
79e17cd014
[clang] Improve bit-field in ref NTTP diagnostic (#71077)
Prior to this, attempts to bind a bit-field to an NTTP of reference type
produced an error because references to subobjects in NTTPs are
disallowed. But C++20 allows references to subobjects in NTTPs generally
(see
[P1907R1](https://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p1907r1.html)).
Without this change, implementing P1907R1 would cause a bug allowing
bit-fields to be bound to reference template arguments.

Extracted from https://reviews.llvm.org/D140996
2024-01-09 18:14:17 +01:00
cor3ntin
69066ab319
[Clang] Fix IsOverload for function templates (#77323)
Functions which correspond but have different template parameter lists
are not redeclarations.

Fixes a regression introduced by af4751

(The patch just moves the template parameters check above if the
signature check)

Fixes #76358
2024-01-08 16:58:48 +01:00
Timm Bäder
f0f16be77e [clang][Sema][NFC] Clean up BuildOverloadedCallExpr 2024-01-08 15:04:52 +01:00
Haojian Wu
10b5b5d6e2
[clang] Fix a crash when referencing the result if the overload fails (#77288)
after 20a05677f9394d4bc9467fe7bc93a4ebd3aeda61

If the overload fails, the `Best` might point to the `end()`,
referencing it leads to asan crashes.
2024-01-08 11:49:36 +01:00
Mariya Podchishchaeva
20a05677f9
[clang] Accept recursive non-dependent calls to functions with deduced return type (#75456)
Treat such calls as dependent since it is much easier to implement.

Fixes https://github.com/llvm/llvm-project/issues/71015
2024-01-05 13:14:51 +01:00
cor3ntin
f40d25151c
[Clang] Implement P2308R1 - Template Parameter Initialization. (#73103)
https://wiki.edg.com/pub/Wg21kona2023/StrawPolls/p2308r1.html

This implements P2308R1 as a DR and resolves CWG2459, CWG2450 and
CWG2049.


Fixes #73666
Fixes #58434 
Fixes #41227
Fixes #49978
Fixes #36296
2023-12-01 17:44:22 +01:00
cor3ntin
205f53010d
[Clang] CWG2789 Overload resolution with implicit and explicit object… (#73493)
… member functions

Implement the resolution to CWG2789 from
https://wiki.edg.com/pub/Wg21kona2023/StrawPolls/p3046r0.html

The DR page is not updated because the issue has not made it to a
published list yet.
2023-11-28 13:30:18 +01:00
Yaxun (Sam) Liu
22078bd9f6 Revert "[CUDA][HIP] ignore implicit host/device attr for override (#72815)"
This reverts commit a1e2c6566305061c115954b048f2957c8d55cb5b.

Revert this patch due to regression. A testcase is:

`template <typename T>
class C {
    explicit C() {};
};

template <> C<int>::C() {};
`
2023-11-22 21:04:55 -05:00
Yaxun (Sam) Liu
a1e2c65663
[CUDA][HIP] ignore implicit host/device attr for override (#72815)
When deciding whether a previous function declaration is an overload or
override, implicit host/device attrs should not be considered.

This fixes the failure for the following code:

`template <typename T>
class C {
    explicit C() {};
};

template <> C<int>::C() {};
`

The issue was introduced by
https://github.com/llvm/llvm-project/pull/72394

sine the template specialization is treated as overload due to implicit
host/device attrs are considered for overload/override differentiation.
2023-11-20 16:06:48 -05:00
PiJoules
b2d62c9a58
[clang] Ensure fixed point conversions work in C++ (#68344) 2023-11-16 13:11:15 -08:00
Ilya Biryukov
18a0313149 [Sema] Fix strict ordering in overload candidate comparisons
This is a follow-up to febf5c97bba7910e796041c9518fce01f31ae826 and
another instance of #64121.

The added test only fails if Clang is built with libc++ and a enabled
debug check for strict weak ordering.
2023-11-10 17:12:24 +01:00
Vlad Serebrennikov
8775947633
[clang][NFC] Refactor clang::Linkage (#71049)
This patch introduces a new enumerator `Invalid = 0`, shifting other enumerators by +1. Contrary to how it might sound, this actually affirms status quo of how this enum is stored in `clang::Decl`:
```
  /// If 0, we have not computed the linkage of this declaration.
  /// Otherwise, it is the linkage + 1.
  mutable unsigned CacheValidAndLinkage : 3;
```
This patch makes debuggers to not be mistaken about enumerator stored in this bit-field. It also converts `clang::Linkage` to a scoped enum.
2023-11-02 20:57:29 +04:00
Vlad Serebrennikov
49fd28d960 [clang][NFC] Refactor ArrayType::ArraySizeModifier
This patch moves `ArraySizeModifier` before `Type` declaration so that it's complete at `ArrayTypeBitfields` declaration. It's also converted to scoped enum along the way.
2023-10-31 18:06:34 +03:00
Utkarsh Saxena
b997ff41c1
Revert [clang] Handle templated operators with reversed arguments and [STLExtras] Undo C++20 hack (#69937)
This breaks C++20 build of LLVM by clang 17 and earlier.
Next steps should be reduce error to a warning for
https://godbolt.org/z/s99bvq4sG
b100ca6f219fda1fed5b92aba8471aa9a6ef8906 or similar should be reapplied
after the bug fix reached clang-18.
2023-10-23 18:09:56 +02:00
Utkarsh Saxena
9330261143
Use the correct namespace for looking up matching operator!= (#68922)
`S.getScopeForContext` determins the **active** scope associated with
the given `declContext`.
This fails to find the matching `operator!=` if candidate `operator==`
was found via ADL since that scope is not active.

Instead, just directly lookup using the namespace decl of `operator==`

Fixes #68901
2023-10-23 14:10:06 +02:00
Ilya Biryukov
febf5c97bb [Sema] Change order of displayed overloads in diagnostics
Make it a strict weak order.

Fixes #64121.

Current implementation uses the definition of ordering from the C++ Standard.
The definition provides only a partial order and cannot be used in sorting
algorithms.

The debug builds of libc++ are capable of detecting that problem
and this failure was found when building Clang with libc++ and
those extra checks enabled, see #64121.

The new ordering is a strict weak order and still
pushes most interesting functions to the start of the list.
In some cases, it leads to better results, e.g.

```
struct Foo {
  operator int();
  operator const char*();
};

void test() { Foo() - Foo(); }
```

Now produces a list with two most relevant builtin operators at the top,
i.e. `operator-(int, int)` and `operator-(const char*, const char*)`.
Previously `operator-(const char*, const char*)` was the first element,
but `operator-(int, int)` was only the 13th element in the output.
This is a consequence of `stable_sort` now being able to compare those
two candidates, which are indistinguishable in the semantic partial order
despite being two local minimums in their respective comparable
subsets.

However, new implementation does not take into account some aspects of
C++ semantics, e.g. which function template is more specialized. This
can also lead to worse ordering sometimes.

Reviewed By: #clang-language-wg, aaron.ballman

Differential Revision: https://reviews.llvm.org/D159351
2023-10-23 12:59:59 +02:00
Utkarsh Saxena
47747da634
[clang] Handle templated operators with reversed arguments (#69595)
https://github.com/llvm/llvm-project/pull/68999 correctly computed
conversion sequence for reversed args to a template operators. This was
a breaking change as code, previously accepted in C++17, starts to break
in C++20.

Example:
```cpp
struct P {};
template<class S> bool operator==(const P&, const S &);

struct A : public P {};
struct B : public P {};
bool check(A a, B b) { return a == b; }  // This is now ambiguous in C++20.
```

In order to minimise widespread breakages, as a clang extension, we had
previously accepted such ambiguities with a warning
(`-Wambiguous-reversed-operator`) for non-template operators. Due to the
same reasons, we extend this relaxation for template operators.

Fixes https://github.com/llvm/llvm-project/issues/53954
2023-10-20 14:40:25 +02:00
Dmitry Chernenkov
a3a0f59a1e Revert "Correctly compute conversion seq for args to fn with reversed param order (#68999)"
This reverts commit e6d0b126c824222fca2f31a2ba571c2ee2bb4760.

See PR for reason

https://github.com/llvm/llvm-project/pull/68999#issuecomment-1768541660
2023-10-18 14:13:48 +00:00
Utkarsh Saxena
e6d0b126c8
Correctly compute conversion seq for args to fn with reversed param order (#68999)
We associated conversion seq for args (when reversed) to the wrong
index.
This lead to clang believing reversed `operator==` a worse overload
candidate than the `operator==` without reversed args when both these
candidate were ambiguous.

Fixes https://github.com/llvm/llvm-project/issues/53954
2023-10-17 20:53:42 +02:00
Botond István Hprváth
66c19167f1
[clang] Choose non-templated ctor as deduction guide unambiguously (#66487)
If there are two guides, one of them generated from a non-templated
constructor
and the other from a templated constructor, then the standard gives
priority to
the first. Clang detected ambiguity before, now the correct guide is
chosen.
The correct behavior is described in this paper:
http://wg21.link/P0620R0

Example for the bug: http://godbolt.org/z/ee3e9qG78

As an unrelated minor change, fix the issue
https://github.com/llvm/llvm-project/issues/64020,
which could've led to incorrect behavior if further development inserted
code after a call to
`isAddressSpaceSubsetOf()`, which specified the two parameters in the
wrong order.

---------

Co-authored-by: hobois <horvath.botond.istvan@gmial.com>
2023-10-04 09:11:43 -07:00
Corentin Jabot
af4751738d [C++] Implement "Deducing this" (P0847R7)
This patch implements P0847R7 (partially),
CWG2561 and CWG2653.

Reviewed By: aaron.ballman, #clang-language-wg

Differential Revision: https://reviews.llvm.org/D140828
2023-10-02 14:33:02 +02:00
Guillot Tony
624c130578 [Clang][C] Fixed a bug where we reject an _Atomic qualified integer in a switch statment
We are currently rejecting an _Atomic qualified integer in a switch statment.
This fixes the issue by doing an Lvalue conversion before trying to match on the type.
Fixes #65557

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D159522
2023-09-20 19:19:02 +02:00
Takuya Shimizu
cf51876dd9
[clang][MSExtentions] Fix invalid overload failure about the loss of __unaligned qualifier (#65248)
Loss of `__unaligned` qualifier does not invalidate overload candidates.
This fixes a regression reported in https://reviews.llvm.org/D153690

Reviewed By: cor3ntin, AaronBallman
PR: https://github.com/llvm/llvm-project/pull/65248
2023-09-08 13:22:07 +09:00
Yaxun (Sam) Liu
9b7763821a
Reland "[CUDA][HIP] Fix overloading resolution in global var init" (#65606)
https://reviews.llvm.org/D158247 caused regressions for HIP on Windows
and was reverted.

A reduced test case is:

```
typedef void (__stdcall* funcTy)();
void invoke(funcTy f);

static void __stdcall callee() noexcept {
}

void foo() {
   invoke(callee);
}
```

It is due to clang missing handling host/device attributes for calling
convention at a few places

This patch fixes that.
2023-09-07 23:18:30 -04:00
Chris Bieneman
400d3261a0 [HLSL] Cleanup support for this as an l-value
The goal of this change is to clean up some of the code surrounding
HLSL using CXXThisExpr as a non-pointer l-value. This change cleans up
a bunch of assumptions and inconsistencies around how the type of
`this` is handled through the AST and code generation.

This change is be mostly NFC for HLSL, and completely NFC for other
language modes.

This change introduces a new member to query for the this object's type
and seeks to clarify the normal usages of the this type.

With the introudction of HLSL to clang, CXXThisExpr may now be an
l-value and behave like a reference type rather than C++'s normal
method of it being an r-value of pointer type.

With this change there are now three ways in which a caller might need
to query the type of `this`:

* The type of the `CXXThisExpr`
* The type of the object `this` referrs to
* The type of the implicit (or explicit) `this` argument

This change codifies those three ways you may need to query
respectively as:

* CXXMethodDecl::getThisType()
* CXXMethodDecl::getThisObjectType()
* CXXMethodDecl::getThisArgType()

This change then revisits all uses of `getThisType()`, and in cases
where the only use was to resolve the pointee type, it replaces the
call with `getThisObjectType()`. In other cases it evaluates whether
the desired returned type is the type of the `this` expr, or the type
of the `this` function argument. The `this` expr type is used for
creating additional expr AST nodes and for member lookup, while the
argument type is used mostly for code generation.

Additionally some cases that used `getThisType` in simple queries could
be substituted for `getThisObjectType`. Since `getThisType` is
implemented in terms of `getThisObjectType` calling the later should be
more efficient if the former isn't needed.

Reviewed By: aaron.ballman, bogner

Differential Revision: https://reviews.llvm.org/D159247
2023-09-05 19:38:50 -05:00
Yaxun (Sam) Liu
27313b68ef Revert "[CUDA][HIP] Fix overloading resolution in global variable initializer"
This reverts commit de0df639724b10001ea9a74539381ea494296be9.

It was reverted due to regression in HIP unit test on Windows:

 In file included from C:\hip-tests\catch\unit\graph\hipGraphClone.cc:37:

 In file included from C:\hip-tests\catch\.\include\hip_test_common.hh:24:

 In file included from C:\hip-tests\catch\.\include/hip_test_context.hh:24:

 In file included from C:/install/native/Release/x64/hip/include\hip/hip_runtime.h:54:

 C:/dk/win\vc\14.31.31107\include\thread:76:70: error: cannot initialize a parameter of type '_beginthreadex_proc_type' (aka 'unsigned int (*)(void *) __attribute__((stdcall))') with an lvalue of type 'const unsigned int (*)(void *) noexcept __attribute__((stdcall))': different exception specifications

    76 |             reinterpret_cast<void*>(_CSTD _beginthreadex(nullptr, 0, _Invoker_proc, _Decay_copied.get(), 0, &_Thr._Id));

       |                                                                      ^~~~~~~~~~~~~

 C:\hip-tests\catch\unit\graph\hipGraphClone.cc:290:21) &>' requested here

    90 |         _Start(_STD forward<_Fn>(_Fx), _STD forward<_Args>(_Ax)...);

       |         ^

 C:\hip-tests\catch\unit\graph\hipGraphClone.cc:290:21) &, 0>' requested here

   311 |     std::thread t(lambdaFunc);

       |                 ^

 C:/dk/win\ms_wdk\e22621\Include\10.0.22621.0\ucrt\process.h:99:40: note: passing argument to parameter '_StartAddress' here

    99 |     _In_      _beginthreadex_proc_type _StartAddress,

       |                                        ^

 1 error generated when compiling for gfx1030.
2023-08-31 09:02:49 -04:00
Yaxun (Sam) Liu
de0df63972 [CUDA][HIP] Fix overloading resolution in global variable initializer
Currently, clang does not resolve certain overloaded functions correctly in the initializer
of global variables, e.g.

template<typename T1, typename U>
T1 mypow(T1, U);

__attribute__((device)) double mypow(double, int);

double t_extent = mypow(1.0, 2);

In the above example, mypow is supposed to resolve to the host version
but clang resolves it to the device version instead, and emits an error
(https://godbolt.org/z/17xxzaa67).

However, if the variable is assigned in a host function, there is no error.
The discrepancy in overloading resolution inside and outside of
a function is due to clang not accounting for the host/device target
when resolving functions called in the initializer of a global variable.

This patch introduces a global host/device target context for CUDA/HIP
for functions called outside of functions. For global variable initialization,
it is determined by the host/device attribute of the variable. For other
situations, a default value of host_device is sufficient.

Reviewed by: Artem Belevich

Differential Revision: https://reviews.llvm.org/D158247

Fixes: SWDEV-416731
2023-08-29 10:17:24 -04:00
Yaxun (Sam) Liu
ea72a4e654 [CUDA][HIP] Fix template argument deduction
nvcc allows using std::malloc and std::free in device code.
When std::malloc or std::free is passed as a template
function argument with template argument deduction,
there is no diagnostics. e.g.

__global__ void kern() {
    void *p = std::malloc(1);
    std::free(p);
}
int main()
{

    std::shared_ptr<float> a;
    a = std::shared_ptr<float>(
      (float*)std::malloc(sizeof(float) * 100),
      std::free
    );
    return 0;
}
However, the same code fails to compile with clang
(https://godbolt.org/z/1roGvo6YY). The reason is
that clang does not have logic to choose a function
argument from an overloaded set of candidates
based on host/device attributes for template argument
deduction.

Currently, clang does have a logic to choose a candidate
based on the constraints of the candidates. This patch
extends that logic to account for the CUDA host/device-based
preference.

Reviewed by: Artem Belevich

Differential Revision: https://reviews.llvm.org/D154300
2023-08-08 17:39:01 -04:00
Sander de Smalen
28b5f3087a [Clang][AArch64] Add/implement ACLE keywords for SME.
This patch adds all the language-level function keywords defined in:

  https://github.com/ARM-software/acle/pull/188 (merged)
  https://github.com/ARM-software/acle/pull/261 (update after D148700 landed)

The keywords are used to control PSTATE.ZA and PSTATE.SM, which are
respectively used for enabling the use of the ZA matrix array and Streaming
mode. This information needs to be available on call sites, since the use
of ZA or streaming mode may have to be enabled or disabled around the
call-site (depending on the IR attributes set on the caller and the
callee). For calls to functions from a function pointer, there is no IR
declaration available, so the IR attributes must be added explicitly to the
call-site.

With the exception of '__arm_locally_streaming' and '__arm_new_za' the
information is part of the function's interface, not just the function
definition, and thus needs to be propagated through the
FunctionProtoType::ExtProtoInfo.

This patch adds the defintions of these keywords, as well as codegen and
semantic analysis to ensure conversions between function pointers are valid
and that no conflicting keywords are set. For example, '__arm_streaming'
and '__arm_streaming_compatible' are mutually exclusive.

Differential Revision: https://reviews.llvm.org/D127762
2023-08-08 07:00:59 +00:00
Podchishchaeva, Mariya
af91092c44 [clang] Do not crash on use of a variadic overloaded operator
Just exit instead.
Fixes https://github.com/llvm/llvm-project/issues/42535

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D156244
2023-08-04 01:44:10 -07:00