723 Commits

Author SHA1 Message Date
Akira Hatanaka
a3283a92ae
[PAC] Add support for __ptrauth type qualifier (#100830)
The qualifier allows programmer to directly control how pointers are
signed when they are stored in a particular variable.

The qualifier takes three arguments: the signing key, a flag specifying
whether address discrimination should be used, and a non-negative
integer that is used for additional discrimination.

```
typedef void (*my_callback)(const void*);
my_callback __ptrauth(ptrauth_key_process_dependent_code, 1, 0xe27a) callback;
```

Co-Authored-By: John McCall rjmccall@apple.com
2025-04-15 12:54:25 -07:00
Mariya Podchishchaeva
88d0b0835d
[MS][clang] Revert vector deleting destructors support (#135611)
Finding operator delete[] is still problematic, without it the extension
is a security hazard, so reverting until the problem with operator
delete[] is figured out.

This reverts the following PRs:
Reland [MS][clang] Add support for vector deleting destructors (llvm#133451)
[MS][clang] Make sure vector deleting dtor calls correct operator delete (llvm#133950)
[MS][clang] Fix crash on deletion of array of pointers (llvm#134088)
[clang] Do not diagnose unused deleted operator delete[] (llvm#134357)
[MS][clang] Error about ambiguous operator delete[] only when required (llvm#135041)
2025-04-14 14:17:36 +02:00
Oliver Hunt
1cd59264aa
[RFC] Initial implementation of P2719 (#113510)
This is a basic implementation of P2719: "Type-aware allocation and
deallocation functions" described at http://wg21.link/P2719

The proposal includes some more details but the basic change in
functionality is the addition of support for an additional implicit
parameter in operators `new` and `delete` to act as a type tag. Tag is
of type `std::type_identity<T>` where T is the concrete type being
allocated. So for example, a custom type specific allocator for `int`
say can be provided by the declaration of

  void *operator new(std::type_identity<int>, size_t, std::align_val_t);
  void  operator delete(std::type_identity<int>, void*, size_t, std::align_val_t);

However this becomes more powerful by specifying templated declarations,
for example

template <typename T> void *operator new(std::type_identity<T>, size_t, std::align_val_t);
template <typename T> void operator delete(std::type_identity<T>, void*, size_t, std::align_val_t););

Where the operators being resolved will be the concrete type being
operated over (NB. A completely unconstrained global definition as above
is not recommended as it triggers many problems similar to a general
override of the global operators).

These type aware operators can be declared as either free functions or
in class, and can be specified with or without the other implicit
parameters, with overload resolution performed according to the existing
standard parameter prioritisation, only with type parameterised
operators having higher precedence than non-type aware operators. The
only exception is destroying_delete which for reasons discussed in the
paper we do not support type-aware variants by default.
2025-04-10 17:13:10 -07:00
Mariya Podchishchaeva
16a1d5d51f
[clang] Do not diagnose unused deleted operator delete[] (#134357)
For vector deleting dtors support we now also search and save operator
delete[]. Avoid diagnosing deleted operator delete[] when doing that
because vector deleting dtors are only called when delete[] is present
and whenever delete[] is present in the TU it will be diagnosed
correctly.

Fixes https://github.com/llvm/llvm-project/issues/134265
2025-04-04 14:44:44 +02:00
Matheus Izvekov
49fd0bf35d
[clang] support pack expansions for trailing requires clauses (#133190) 2025-04-03 12:36:15 -03:00
Mariya Podchishchaeva
8a691cc615
[MS][clang] Make sure vector deleting dtor calls correct operator delete (#133950)
During additional testing I spotted that vector deleting dtor calls
operator delete, not operator delete[] when performing array deletion.
This patch fixes that.
2025-04-02 09:25:43 +02:00
Jason Rice
f7c71f1622
[Clang][P1061] Consolidate ResolvedUnpexandedPackExpr into FunctionParmPackExpr (#125394)
This merges the functionality of ResolvedUnexpandedPackExpr into
FunctionParmPackExpr. I also added a test to show that
https://github.com/llvm/llvm-project/issues/125103 should be fixed with
this. I put the removal of ResolvedUnexpandedPackExpr in its own commit.
Let me know what you think.

Fixes #125103
2025-02-18 09:42:24 +01:00
Chris B
761d422441
[HLSL] Implement HLSL intialization list support (#123141)
This PR implements HLSL's initialization list behvaior as specified in
the draft language specifcation under

[*Decl.Init.Agg*](https://microsoft.github.io/hlsl-specs/specs/hlsl.html#Decl.Init.Agg).

This behavior is a bit unusual for C/C++ because intermediate braces in
initializer lists are ignored and a whole array of additional
conversions occur unintuitively to how initializaiton works in C.

The implementaiton in this PR generates a valid C/C++ initialization
list AST for the HLSL initializer so that there are no changes required
to Clang's CodeGen to support this. This design will also allow us to
use Clang's rewrite to convert HLSL initializers to valid C/C++
initializers that are equivalent. It does have the downside that it will
generate often redundant accesses during codegen. The IR optimizer is
extremely good at eliminating those so this will have no impact on the
final executable performance.

There is some opportunity for optimizing the initializer list generation
that we could consider in subsequent commits. One notable opportunity
would be to identify aggregate objects that occur in the same place in
both initializers and do not require converison, those aggregates could
be initialized as aggregates rather than fully scalarized.

Closes #56067

---------

Co-authored-by: Finn Plummer <50529406+inbelic@users.noreply.github.com>
Co-authored-by: Helena Kotas <hekotas@microsoft.com>
Co-authored-by: Justin Bogner <mail@justinbogner.com>
2025-02-15 13:21:36 -06:00
Jason Rice
abc8812df0
[Clang][P1061] Add stuctured binding packs (#121417)
This is an implementation of P1061 Structure Bindings Introduce a Pack
without the ability to use packs outside of templates. There is a couple
of ways the AST could have been sliced so let me know what you think.
The only part of this change that I am unsure of is the
serialization/deserialization stuff. I followed the implementation of
other Exprs, but I do not really know how it is tested. Thank you for
your time considering this.

---------

Co-authored-by: Yanzuo Liu <zwuis@outlook.com>
2025-01-29 21:43:52 +01:00
antangelo
f94c481543
[clang] Track source deduction guide for alias template deduction guides (#123875)
For deduction guides generated from alias template CTAD, store the
deduction guide they were originated from. The source kind is also
maintained for future expansion in CTAD from inherited constructors.

This tracking is required to determine whether an alias template already
has a deduction guide corresponding to some deduction guide on the
original template, in order to support deduction guides for the alias
from deduction guides declared after the initial usage.
2025-01-27 18:59:12 -05:00
Kazu Hirata
563c7c5539
[clang] Migrate away from PointerUnion::dyn_cast (NFC) (#124425)
Note that PointerUnion::dyn_cast has been soft deprecated in
PointerUnion.h:

  // FIXME: Replace the uses of is(), get() and dyn_cast() with
  //        isa<T>, cast<T> and the llvm::dyn_cast<T>

This patch migrates uses of PointerUnion::dyn_cast to
dyn_cast_if_present (see the definition of PointerUnion::dyn_cast).
Note that we cannot use dyn_cast in any of the migrations in this
patch; placing

  assert(!X.isNull());

just before any of dyn_cast_if_present in this patch triggers some
failure in check-clang.
2025-01-25 14:05:01 -08:00
higher-performance
1594413d5e
Add Clang attribute to ensure that fields are initialized explicitly (#102040)
This is a new Clang-specific attribute to ensure that field
initializations are performed explicitly.

For example, if we have
```
struct B {
  [[clang::explicit]] int f1;
};
```
then the diagnostic would trigger if we do `B b{};`:
```
field 'f1' is left uninitialized, but was marked as requiring initialization
```

This prevents callers from accidentally forgetting to initialize fields,
particularly when new fields are added to the class.
2025-01-14 13:31:12 -05:00
Timm Baeder
cfe26358e3
Reapply "[clang] Avoid re-evaluating field bitwidth" (#122289) 2025-01-11 07:12:37 +01:00
Aaron Ballman
5ff7f479a1
[C++20] Destroying delete and deleted destructors (#118800)
When a destroying delete overload is selected, the destructor is not
automatically called. Therefore, the destructor can be deleted without
causing the program to be ill-formed.

Fixes #46818
2025-01-09 08:29:19 -05:00
Timm Bäder
59bdea24b0 Revert "[clang] Avoid re-evaluating field bitwidth (#117732)"
This reverts commit 81fc3add1e627c23b7270fe2739cdacc09063e54.

This breaks some LLDB tests, e.g.
SymbolFile/DWARF/x86/no_unique_address-with-bitfields.cpp:

lldb: ../llvm-project/clang/lib/AST/Decl.cpp:4604: unsigned int clang::FieldDecl::getBitWidthValue() const: Assertion `isa<ConstantExpr>(getBitWidth())' failed.
2025-01-08 15:09:52 +01:00
Timm Baeder
81fc3add1e
[clang] Avoid re-evaluating field bitwidth (#117732)
Save the bitwidth value as a `ConstantExpr` with the value set. Remove
the `ASTContext` parameter from `getBitWidthValue()`, so the latter
simply returns the value from the `ConstantExpr` instead of
constant-evaluating the bitwidth expression every time it is called.
2025-01-08 14:45:19 +01:00
Vladislav Belov
e1cb316cfd
Reapply "[clang] Fix name lookup for dependent bases" (#118003)
Unlike the previous version
(https://github.com/llvm/llvm-project/pull/114978), this patch also
removes an unnecessary assert that causes Clang to crash when compiling
such tests. (clang/lib/AST/DeclCXX.cpp)

https://lab.llvm.org/buildbot/#/builders/52/builds/4021

```c++
template <class T> 
class X {
public:
  X() = default;
  virtual ~X() = default;

  virtual int foo(int x, int y, T &entry) = 0;

  void bar() {
    struct Y : public X<T> {
      Y() : X() {}

      int foo(int, int, T &) override {
        return 42;
      }
    };
  }
};
```

the assertions: 

```c++
llvm-project/clang/lib/AST/DeclCXX.cpp:2508: void clang::CXXMethodDecl::addOverriddenMethod(const CXXMethodDecl *): Assertion `!MD->getParent()->isDependentContext() && "Can't add an overridden method to a class template!"' failed.
```

I believe that this assert is unnecessary and contradicts the logic of
this patch. After its removal, Clang was successfully built using
itself, and all tests passed.
2024-12-03 16:46:01 +03:00
A. Jiang
63c5a422f0
[Clang] Fix constexpr-ness on implicitly deleted destructors (#116359)
In C++20, a defaulted but implicitly deleted destructor is constexpr if
and only if the class has no virtual base class. This hasn't been
changed in C++23 by P2448R2.

Constexpr-ness on a deleted destructor affects almost nothing. The
`__is_literal` intrinsic is related, while the corresponding
`std::is_literal_type(_v)` utility has been removed in C++20. A recently
added example in `test/AST/ByteCode/cxx23.cpp` will become valid, and
the example is already accepted by GCC.

Clang currently behaves correctly in C++23 mode, because the
constexpr-ness on defaulted destructor is relaxed by P2448R2. But we
should make similar relaxation for an implicitly deleted destructor.

Fixes #85550.
2024-11-28 09:19:02 +08:00
Kazu Hirata
63d9ef5e37
[AST] Migrate away from PointerUnion::{is,get} (NFC) (#117469)
Note that PointerUnion::{is,get} have been soft deprecated in
PointerUnion.h:

  // FIXME: Replace the uses of is(), get() and dyn_cast() with
  //        isa<T>, cast<T> and the llvm::dyn_cast<T>

I'm not touching PointerUnion::dyn_cast for now because it's a bit
complicated; we could blindly migrate it to dyn_cast_if_present, but
we should probably use dyn_cast when the operand is known to be
non-null.
2024-11-24 07:28:20 -08:00
Kazu Hirata
dec6324cb0
[AST] Remove unused includes (NFC) (#116549)
Identified with misc-include-cleaner.
2024-11-17 09:36:48 -08:00
Krystian Stasiowski
44ab3805b5
Revert "Reapply "[Clang][Sema] Refactor collection of multi-level template argument lists (#106585, #111173)" (#111852)" (#115159)
This reverts commit 2bb3d3a3f32ffaef3d9b6a27db7f1941f0cb1136.
2024-11-06 09:25:29 -05:00
Krystian Stasiowski
79f4d8f014
Revert "Reapply "[Clang][Sema] Always use latest redeclaration of primary template" (#114569)" (#115156)
This reverts commit b24650e814e55d90acfc40acf045456c98f32b9c.
2024-11-06 08:38:59 -05:00
Krystian Stasiowski
b24650e814
Reapply "[Clang][Sema] Always use latest redeclaration of primary template" (#114569)
This patch reapplies #114258, fixing an infinite recursion bug in
`ASTImporter` that occurs when importing the primary template of a class
template specialization when the latest redeclaration of that template
is a friend declaration in the primary template.
2024-11-01 16:15:33 -04:00
Felipe de Azevedo Piovezan
4afa978756
Revert "[Clang][Sema] Always use latest redeclaration of primary template" (#114304)
Clang importer doesn't seem to work well with this change, see
discussion in the original PR.

Reverts llvm/llvm-project#114258
2024-10-30 14:04:26 -07:00
Krystian Stasiowski
90786adade
[Clang][Sema] Always use latest redeclaration of primary template (#114258)
This patch fixes a couple of regressions introduced in #111852.

Consider:

```
template<typename T>
struct A
{
    template<bool U>
    static constexpr bool f() requires U
    {
        return true;
    }
};

template<>
template<bool U>
constexpr bool A<short>::f() requires U
{
    return A<long>::f<U>();
}

template<>
template<bool U>
constexpr bool A<long>::f() requires U
{
    return true;
}

static_assert(A<short>::f<true>()); // crash here
```

This crashes because when collecting template arguments from the _first_
declaration of `A<long>::f<true>` for constraint checking, we don't add
the template arguments from the enclosing class template specialization
because there exists another redeclaration that is a member
specialization.

This also fixes the following example, which happens for a similar
reason:
```
// input.cppm

export module input;

export template<int N>
constexpr int f();

template<int N>
struct A {
  template<int J>
  friend constexpr int f();
};

template struct A<0>;

template<int N>
constexpr int f() {
  return N;
}
```

```
// input.cpp

import input;

static_assert(f<1>() == 1); // error: static assertion failed
```
2024-10-30 14:50:40 -04:00
Jay Foad
4dd55c567a
[clang] Use {} instead of std::nullopt to initialize empty ArrayRef (#109399)
Follow up to #109133.
2024-10-24 10:23:40 +01:00
Helena Kotas
9b984554d7
[HLSL][NFC] Move IsIntangibleType from SemaHLSL to Type to make it accessible outside of Sema (#113206)
Moves `IsIntangibleType` from SemaHLSL to Type class and renames it to
`isHLSLIntangibleType`. The existing `isHLSLIntangibleType` is renamed
to `isHLSLBuiltinIntangibleType` and updated to return true only for the
builtin `__hlsl_resource_t` type.

This change makes `isHLSLIntangibleType` functionality accessible
outside of Sema, for example from clang CodeGen.
2024-10-22 16:32:09 -07:00
Rajveer Singh Bharadwaj
73057349a2
[clang] Allow class with anonymous union member to be const-default-constructible even if a union member has a default member initializer (#95854) (#96301)
Resolves #95854

-- As per https://eel.is/c++draft/dcl.init#general-8.3
2024-10-22 10:31:20 +02:00
Helena Kotas
3b4512074e
[HLSL] Make HLSLAttributedResourceType canonical and add code paths to convert HLSL types to DirectX target types (#110327)
Translates `RWBuffer` and `StructuredBuffer` resources buffer types to
DirectX target types `dx.TypedBuffer` and `dx.RawBuffer`.

Includes a change of `HLSLAttributesResourceType` from 'sugar' type to
full canonical type. This is required for codegen and other clang
infrastructure to work property on HLSL resource types.

Fixes #95952 (part 2/2)
2024-10-15 13:38:15 -07:00
Krystian Stasiowski
2bb3d3a3f3
Reapply "[Clang][Sema] Refactor collection of multi-level template argument lists (#106585, #111173)" (#111852)
This patch reapplies #111173, fixing a bug when instantiating dependent
expressions that name a member template that is later explicitly
specialized for a class specialization that is implicitly instantiated.

The bug is addressed by adding the `hasMemberSpecialization` function,
which return `true` if _any_ redeclaration is a member specialization.
This is then used when determining the instantiation pattern for a
specialization of a template, and when collecting template arguments for
a specialization of a template.
2024-10-11 14:08:06 -04:00
Krystian Stasiowski
1dff3309fd
Revert "Reapply "[Clang][Sema] Refactor collection of multi-level template argument lists (#106585)" (#111173)" (#111766)
This reverts commit 4da8ac34f76e707ab94380b94f616457cfd2cb83.
2024-10-09 17:49:32 -04:00
Krystian Stasiowski
4da8ac34f7
Reapply "[Clang][Sema] Refactor collection of multi-level template argument lists (#106585)" (#111173)
Reapplies #106585, fixing an issue where non-dependent names of member
templates appearing prior to that member template being explicitly
specialized for an implicitly instantiated class template specialization
would incorrectly use the definition of the explicitly specialized
member template.
2024-10-08 10:14:09 -04:00
Sirraide
f01364ebc8
[Clang] Instantiate the correct lambda call operator (#110446)
This is a fix for the following issue: when a lambda’s class type is
merged across modules (e.g. because it is defined in a template in the
GMF of some module `A`, and some other module `B` both imports `A` and
has the same template in its GMF), then `getLambdaCallOperator()` might
return the wrong operator (e.g. while compiling `B`, the lambda’s class
type would be the one attached to `B`’s GMF, but the call operator ends
up being the one attached to `A`’s GMF).

This causes issues in situations where the call operator is in a
template and accesses declarations in the surrounding context: when
those declarations are instantated, a mapping is introduced from the
original node in the template to that of the instantiation. If such an
instantiation happens in `B`, and we then try to instantiate `A`’s call
operator, any nodes in that call operator refer to declarations in the
template in `A`, but the `LocalInstantiationScope` only contains
mappings for declarations in `B`! This causes the following assertion
(for godbolt links and more, see the issue below):

```
Assertion `isa<LabelDecl>(D) && "declaration not instantiated in this scope"' failed.
```

We now walk the redecl chain of the call operator to find the
one that is in the same module as the record decl.

This fixes #110401.
2024-10-08 13:34:00 +02:00
Younan Zhang
915df1ae41
[Clang] Implement CWG 2707 "Deduction guides cannot have a trailing requires-clause" (#110473)
Closes https://github.com/llvm/llvm-project/issues/98595
2024-10-01 07:27:15 +08:00
Helena Kotas
9efe377307
[HLSL] Implement '__builtin_hlsl_is_intangible' type trait (#104544)
Implements `__builtin_hlsl_is_intangible` type trait.

HLSL intangible types are special implementation-defined types such as
resource handles or samplers. Any class that is an array of intangible
type or contains base class or members of intangible types is also an
intangible type.

Fixes #[102954](https://github.com/llvm/llvm-project/issues/102954)
2024-09-04 16:03:13 -07:00
Mital Ashok
5d7357cc9e
[Clang] Fix definition of layout-compatible to ignore empty classes (#92103)
Also changes the behaviour of `__builtin_is_layout_compatible`

None of the historic nor the current definition of layout-compatible
classes mention anything about base classes (other than implicitly
through being standard-layout) and are defined in terms of members, not
direct members.
2024-08-01 18:05:46 +04:00
Oleksandr T.
430b254503
[Clang] Do not attempt to access the DefinitionData of an incomplete type (#99998)
We were asserting here because we were trying to access the 
`DefinitionData` of an incomplete type in the `Visit` lambda in 
`CXXRecordDecl::hasSubobjectAtOffsetZeroOfEmptyBaseType`.

The code that creates `FieldDecl`s always marks them as invalid 
if their type is incomplete, so checking whether the field decl 
whose type we’re about to look at is invalid fixes this issue.

Fixes #99868.
2024-07-23 10:40:12 +02:00
Krystian Stasiowski
e6ec7c8f74
[Clang][AST] Move NamespaceDecl bits to DeclContext (#98567)
Currently, `NamespaceDecl` has a member `AnonOrFirstNamespaceAndFlags`
which stores a few pieces of data:
- a bit indicating whether the namespace was declared `inline`, and
- a bit indicating whether the namespace was declared as a
_nested-namespace-definition_, and
- a pointer a `NamespaceDecl` that either stores:
- a pointer to the first declaration of that namespace if the
declaration is no the first declaration, or
- a pointer to the unnamed namespace that inhabits the namespace
otherwise.

`Redeclarable` already stores a pointer to the first declaration of an
entity, so it's unnecessary to store this in `NamespaceDecl`.
`DeclContext` has 8 bytes in which various bitfields can be stored for a
declaration, so it's not necessary to store these in `NamespaceDecl`
either. We only need to store a pointer to the unnamed namespace that
inhabits the first declaration of a namespace. This patch moves the two
bits currently stored in `NamespaceDecl` to `DeclContext`, and only
stores a pointer to the unnamed namespace that inhabits a namespace in
the first declaration of that namespace. Since `getOriginalNamespace`
always returns the same `NamespaceDecl` as `getFirstDecl`, this function
is removed to avoid confusion.
2024-07-15 13:57:56 -04:00
MagentaTreehouse
a66275090e
[Clang] [NFC] Use range-based for loops (#96831)
Use range-based for loops. In addition, extracted a loop from
`CXXRecordDecl::completeDefinition` to eliminate the `Done` flag, and
only construct `MyFinalOverriders` when `FinalOverriders` is null.
2024-07-01 14:55:23 +02:00
Chuanqi Xu
5a0181f568 [serialization] no transitive decl change (#92083)
Following of https://github.com/llvm/llvm-project/pull/86912

The motivation of the patch series is that, for a module interface unit
`X`, when the dependent modules of `X` changes, if the changes is not
relevant with `X`, we hope the BMI of `X` won't change. For the specific
patch, we hope if the changes was about irrelevant declaration changes,
we hope the BMI of `X` won't change. **However**, I found the patch
itself is not very useful in practice, since the adding or removing
declarations, will change the state of identifiers and types in most
cases.

That said, for the most simple example,

```
// partA.cppm
export module m:partA;

// partA.v1.cppm
export module m:partA;
export void a() {}

// partB.cppm
export module m:partB;
export void b() {}

// m.cppm
export module m;
export import :partA;
export import :partB;

// onlyUseB;
export module onlyUseB;
import m;
export inline void onluUseB() {
    b();
}
```

the BMI of `onlyUseB` will change after we change the implementation of
`partA.cppm` to `partA.v1.cppm`. Since `partA.v1.cppm` introduces new
identifiers and types (the function prototype).

So in this patch, we have to write the tests as:

```
// partA.cppm
export module m:partA;
export int getA() { ... }
export int getA2(int) { ... }

// partA.v1.cppm
export module m:partA;
export int getA() { ... }
export int getA(int) { ... }
export int getA2(int) { ... }

// partB.cppm
export module m:partB;
export void b() {}

// m.cppm
export module m;
export import :partA;
export import :partB;

// onlyUseB;
export module onlyUseB;
import m;
export inline void onluUseB() {
    b();
}
```

so that the new introduced declaration `int getA(int)` doesn't introduce
new identifiers and types, then the BMI of `onlyUseB` can keep
unchanged.

While it looks not so great, the patch should be the base of the patch
to erase the transitive change for identifiers and types since I don't
know how can we introduce new types and identifiers without introducing
new declarations. Given how tightly the relationship between
declarations, types and identifiers, I think we can only reach the ideal
state after we made the series for all of the three entties.

The design of the patch is similar to
https://github.com/llvm/llvm-project/pull/86912, which extends the
32-bit DeclID to 64-bit and use the higher bits to store the module file
index and the lower bits to store the Local Decl ID.

A slight difference is that we only use 48 bits to store the new DeclID
since we try to use the higher 16 bits to store the module ID in the
prefix of Decl class. Previously, we use 32 bits to store the module ID
and 32 bits to store the DeclID. I don't want to allocate additional
space so I tried to make the additional space the same as 64 bits. An
potential interesting thing here is about the relationship between the
module ID and the module file index. I feel we can get the module file
index by the module ID. But I didn't prove it or implement it. Since I
want to make the patch itself as small as possible. We can make it in
the future if we want.

Another change in the patch is the new concept Decl Index, which means
the index of the very big array `DeclsLoaded` in ASTReader. Previously,
the index of a loaded declaration is simply the Decl ID minus
PREDEFINED_DECL_NUMs. So there are some places they got used
ambiguously. But this patch tried to split these two concepts.

As https://github.com/llvm/llvm-project/pull/86912 did, the change will
increase the on-disk PCM file sizes. As the declaration ID may be the
most IDs in the PCM file, this can have the biggest impact on the size.
In my experiments, this change will bring 6.6% increase of the on-disk
PCM size. No compile-time performance regression observed. Given the
benefits in the motivation example, I think the cost is worthwhile.
2024-06-07 20:21:55 +08:00
Chuanqi Xu
4f70c5ec4a Revert "[serialization] no transitive decl change (#92083)"
This reverts commit 5c104879c1a98eeb845c03e7c45206bd48e88f0c.

The ArmV7 bot is complaining the change breaks the alignment.
2024-06-07 11:29:09 +08:00
Chuanqi Xu
5c104879c1 [serialization] no transitive decl change (#92083)
Following of https://github.com/llvm/llvm-project/pull/86912

The motivation of the patch series is that, for a module interface unit
`X`, when the dependent modules of `X` changes, if the changes is not
relevant with `X`, we hope the BMI of `X` won't change. For the specific
patch, we hope if the changes was about irrelevant declaration changes,
we hope the BMI of `X` won't change. **However**, I found the patch
itself is not very useful in practice, since the adding or removing
declarations, will change the state of identifiers and types in most
cases.

That said, for the most simple example,

```
// partA.cppm
export module m:partA;

// partA.v1.cppm
export module m:partA;
export void a() {}

// partB.cppm
export module m:partB;
export void b() {}

// m.cppm
export module m;
export import :partA;
export import :partB;

// onlyUseB;
export module onlyUseB;
import m;
export inline void onluUseB() {
    b();
}
```

the BMI of `onlyUseB` will change after we change the implementation of
`partA.cppm` to `partA.v1.cppm`. Since `partA.v1.cppm` introduces new
identifiers and types (the function prototype).

So in this patch, we have to write the tests as:

```
// partA.cppm
export module m:partA;
export int getA() { ... }
export int getA2(int) { ... }

// partA.v1.cppm
export module m:partA;
export int getA() { ... }
export int getA(int) { ... }
export int getA2(int) { ... }

// partB.cppm
export module m:partB;
export void b() {}

// m.cppm
export module m;
export import :partA;
export import :partB;

// onlyUseB;
export module onlyUseB;
import m;
export inline void onluUseB() {
    b();
}
```

so that the new introduced declaration `int getA(int)` doesn't introduce
new identifiers and types, then the BMI of `onlyUseB` can keep
unchanged.

While it looks not so great, the patch should be the base of the patch
to erase the transitive change for identifiers and types since I don't
know how can we introduce new types and identifiers without introducing
new declarations. Given how tightly the relationship between
declarations, types and identifiers, I think we can only reach the ideal
state after we made the series for all of the three entties.

The design of the patch is similar to
https://github.com/llvm/llvm-project/pull/86912, which extends the
32-bit DeclID to 64-bit and use the higher bits to store the module file
index and the lower bits to store the Local Decl ID.

A slight difference is that we only use 48 bits to store the new DeclID
since we try to use the higher 16 bits to store the module ID in the
prefix of Decl class. Previously, we use 32 bits to store the module ID
and 32 bits to store the DeclID. I don't want to allocate additional
space so I tried to make the additional space the same as 64 bits. An
potential interesting thing here is about the relationship between the
module ID and the module file index. I feel we can get the module file
index by the module ID. But I didn't prove it or implement it. Since I
want to make the patch itself as small as possible. We can make it in
the future if we want.

Another change in the patch is the new concept Decl Index, which means
the index of the very big array `DeclsLoaded` in ASTReader. Previously,
the index of a loaded declaration is simply the Decl ID minus
PREDEFINED_DECL_NUMs. So there are some places they got used
ambiguously. But this patch tried to split these two concepts.

As https://github.com/llvm/llvm-project/pull/86912 did, the change will
increase the on-disk PCM file sizes. As the declaration ID may be the
most IDs in the PCM file, this can have the biggest impact on the size.
In my experiments, this change will bring 6.6% increase of the on-disk
PCM size. No compile-time performance regression observed. Given the
benefits in the motivation example, I think the cost is worthwhile.
2024-06-07 10:47:53 +08:00
Chuanqi Xu
d86cc73bbf [NFC] [Serialization] Avoid using DeclID directly as much as possible
This patch tries to remove all the direct use of DeclID except the real
low level reading and writing. All the use of DeclID is converted to
the use of LocalDeclID or GlobalDeclID. This is helpful to increase the
readability and type safety.
2024-04-25 14:59:09 +08:00
Chuanqi Xu
72b58146b1 Revert "[NFC] [Serialization] Avoid using DeclID directly as much as possible"
This reverts commit 42070a5c092ed420bf92ebf38229c594885e94c7.

I forgot to touch lldb.
2024-04-25 14:26:07 +08:00
Chuanqi Xu
42070a5c09 [NFC] [Serialization] Avoid using DeclID directly as much as possible
This patch tries to remove all the direct use of DeclID except the real
low level reading and writing. All the use of DeclID is converted to
the use of LocalDeclID or GlobalDeclID. This is helpful to increase the
readability and type safety.
2024-04-25 14:14:05 +08:00
Chuanqi Xu
c2a98fdeb3
[NFC] Move DeclID from serialization/ASTBitCodes.h to AST/DeclID.h (#89873)
Previously, the DeclID is defined in serialization/ASTBitCodes.h under
clang::serialization namespace. However, actually the DeclID is not
purely used in serialization part. The DeclID is already widely used in
AST and all around the clang project via classes like `LazyPtrDecl` or
calling `ExternalASTSource::getExernalDecl()`. All such uses are via the
raw underlying type of `DeclID` as `uint32_t`. This is not pretty good.

This patch moves the DeclID class family to a new header `AST/DeclID.h`
so that the whole project can use the wrapped class `DeclID`,
`GlobalDeclID` and `LocalDeclID` instead of the raw underlying type.
This can improve the readability and the type safety.
2024-04-25 13:53:22 +08:00
Chuanqi Xu
aac695da42 [NFC] [Serialization] Use semantical type 'DeclID' for 'CreateDeserialized'
Previously we use 'unsigned' as the type of ID in 'CreateDeserialized'.

And the type of `DeclID` in serialization is 'uint32_t', so there is
minor inconsistency.

Also more importantly, if we want to extend the type of DeclID from
uint32_t to uint64_t, we may be in trouble due to we forgot updating the
a lot of 'CreateDeserialized'.

So this patch tries to use semantical type 'DeclID' for
'*Decl::CreateDeserialized' to make sure it is tightly consistent.
2024-04-19 16:24:47 +08:00
Timm Baeder
3d56ea05b6
[clang][NFC] Fix FieldDecl::isUnnamedBitfield() capitalization (#89048)
We always capitalize bitfield as "BitField".
2024-04-18 07:39:29 +02:00
Nikolas Klauser
367f355fbf
Reapply "[clang] Fix crash when declaring invalid lambda member" (#85427)
This re-applies #74110 with the crashing code disabled in C++11. I'll
try to fix the new crash in it's own patch.
2024-03-16 12:36:33 +01:00
Amy Huang
f9a1478200
Reapply "[Clang][C++23] Implement P2448R2 ..." (#85136) (#85145)
This reverts commit 003e292f9895a9cf4e30688269efa668d1fcbb09 because
there were dependent changes in the codebase that now fail.
2024-03-13 23:15:01 +00:00