- The FP8 scalar type (`__mfp8`) was described as a vector type
- The FP8 vector types were described/assumed to have integer element
type (the element type ought to be `__mfp8`)
- Add support for `m` type specifier (denoting `__mfp8`) in
`DecodeTypeFromStr` and create builtin function prototypes using that
specifier, instead of `int8_t`
Reimplement Neon FP8 vector types using attribute `neon_vector_type`
instead of having them as builtin types.
This allows to implement FP8 Neon intrinsics without the need to add
special cases for these types when using `__builtin_shufflevector`
or bitcast (using C-style cast operator) between vectors, both
extensively used in the generated code in `arm_neon.h`.
Similar to arm_sve_vector_bits, the mangling of function types is
implemented as a pseudo template if there are any SME attributes
present, i.e.
`__SME_ATTRS<normal_function_type, sme_state>`
For example, the following function:
`void f(svint8_t (*fn)() __arm_streaming) { fn(); }`
would be mangled as:
`_Z1fP11__SME_ATTRSIFu10__SVInt8_tELj1EE`
See https://github.com/ARM-software/acle/pull/358
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)
Recently, Solaris bootstrap got broken because Solaris uses a
non-standard mangling of `std::tm` and a few others. This was fixed with
a hack in PR #100724. The Solaris ABI requires mangling `std::tm` as
`tm` and similarly for `std::div_t`, `std::ldiv_t`, and `std::lconv`,
which is what this patch implements. The hack needs to stay in place to
allow building with older versions of `clang`.
Tested on `amd64-pc-solaris2.11`, `sparcv9-sun-solaris2.11` (2-stage
builds with both `clang-19` and `gcc-14` as build compiler), and
`x86_64-pc-linux-gnu`.
The 'tile' clause shares quite a bit of the rules with 'collapse', so a
followup patch will add those tests/behaviors. This patch deals with
adding the AST node.
The 'tile' clause takes a series of integer constant expressions, or *.
The asterisk is now represented by a new OpenACCAsteriskSizeExpr node,
else this clause is very similar to others.
Fix#108015
The `mangleNameOrStandardSubstitution` function does not add the RD type
into the substitution, which causes the mangling of the \<base type\> to
be incorrect.
Rename `mangleNameOrStandardSubstitution` to `mangleCXXRecordDecl` and add `Record` as a substitution
Some switch statements require all SVE builtin types to be manually
specified. This patch refactors the SVE_*_TYPE macros so that such code
can be generated during preprocessing.
I've tried to establish a minimal interface that covers all types where
no special information is required and then created a set of macros that
are dedicated to specific datatypes (i.e. int, float).
This patch is groundwork to simplify the changing of SVE tuple types to
become struct based as well as work to support the FP8 ACLE.
This extends default argument deduction to cover class templates as
well, applying only to partial ordering, adding to the provisional
wording introduced in https://github.com/llvm/llvm-project/pull/89807.
This solves some ambuguity introduced in P0522 regarding how template
template parameters are partially ordered, and should reduce the
negative impact of enabling `-frelaxed-template-template-args` by
default.
Given the following example:
```C++
template <class T1, class T2 = float> struct A;
template <class T3> struct B;
template <template <class T4> class TT1, class T5> struct B<TT1<T5>>; // #1
template <class T6, class T7> struct B<A<T6, T7>>; // #2
template struct B<A<int>>;
```
Prior to P0522, `#2` was picked. Afterwards, this became ambiguous. This
patch restores the pre-P0522 behavior, `#2` is picked again.
HLSL output parameters are denoted with the `inout` and `out` keywords
in the function declaration. When an argument to an output parameter is
constructed a temporary value is constructed for the argument.
For `inout` pamameters the argument is initialized via copy-initialization
from the argument lvalue expression to the parameter type. For `out`
parameters the argument is not initialized before the call.
In both cases on return of the function the temporary value is written
back to the argument lvalue expression through an implicit assignment
binary operator with casting as required.
This change introduces a new HLSLOutArgExpr ast node which represents
the output argument behavior. The OutArgExpr has three defined children:
- An OpaqueValueExpr of the argument lvalue expression.
- An OpaqueValueExpr of the copy-initialized parameter.
- A BinaryOpExpr assigning the first with the value of the second.
Fixes#87526
---------
Co-authored-by: Damyan Pepper <damyanp@microsoft.com>
Co-authored-by: John McCall <rjmccall@gmail.com>
Introducing `HLSLAttributedResourceType` - a new type that is similar to
`AttributedType` but with additional data specific to HLSL resources.
`AttributeType` currently only stores an attribute kind and no
additional data from the type attribute parameters. This does not really
work for HLSL resources since its type attributes contain non-boolean
values that need to be retained as well.
For example:
```
template <typename T> class RWBuffer {
__hlsl_resource_t [[hlsl::resource_class(uav)]] [[hlsl::is_rov]] handle;
};
```
The data `HLSLAttributedResourceType` needs to eventually store are:
- resource class (SRV, UAV, CBuffer, Sampler)
- texture dimension(1-3)
- flags is_rov, is_array, is_feedback and is_multisample
- contained type
All of these values except contained type will be stored in
`HLSLAttributedResourceType::Attributes` struct and accessed
individually via the fields. There is also `Data` alias that covers all
of these values as a `unsigned` which is used for hashing and the AST
type serialization.
During type attribute processing all HLSL type attributes will be
validated and collected by SemaHLSL (by
`SemaHLSL::handleResourceTypeAttr`) and in the end combined into a
single `HLSLAttributedResourceType` instance (in
`SemaHLSL::ProcessResourceTypeAttributes`). `SemaHLSL` will also need to
short-term store the `TypeLoc` information for the new type that will be
grabbed by `TypeSpecLocFiller` soon after the type is created.
Part 1/2 of #104861
As agreed on https://github.com/itanium-cxx-abi/cxx-abi/issues/109 these
placeholders should be mangled as a `template-prefix` production.
```
<template-prefix> ::= <template unqualified-name> # global template
::= <prefix> <template unqualified-name> # nested template
::= <template-param> # template template parameter
::= <substitution>
```
Previous to this patch, the template template parameter case was not
handled, and template template parameters were incorrectly being handled
as unqualified-names.
Before #95202, DeducedTemplateType was not canonicalized correctly, so
that template template parameter declarations were retained
uncanonicalized.
After #95202, they are correctly canonicalized, but this now leads to
these TTPs being anonymous entities, where the mangling implementation
correctly doesn't expect an anonymous declaration of this kind, leading
to a crash.
Fixes#106182.
Enabling __ptr32 keyword to support in Clang for z/OS. It is represented
by addrspace(1) in LLVM IR. Unlike existing implementation, __ptr32 is
not mangled into symbol names for z/OS.
HLSL has a set of intangible types which are described in in the
[draft HLSL Specification
(**[Basic.types]**)](https://microsoft.github.io/hlsl-specs/specs/hlsl.pdf):
There are special implementation-defined types such as handle types,
which fall into a category of standard intangible types. Intangible
types are types that have no defined object representation or value
representation, as such the size is unknown at compile time.
A class type T is an intangible class type if it contains an base
classes or members of intangible class type, standard intangible type,
or arrays of such types. Standard intangible types and intangible class
types are collectively called intangible
types([9](https://microsoft.github.io/hlsl-specs/specs/hlsl.html#Intangible)).
This PR implements one standard intangible type `__hlsl_resource_t`
and sets up the infrastructure that will make it easier to add more
in the future, such as samplers or raytracing payload handles. The
HLSL intangible types are declared in
`clang/include/clang/Basic/HLSLIntangibleTypes.def` and this file is
included with related macro definition in most places that require edits
when a new type is added.
The new types are added as keywords and not typedefs to make sure they
cannot be redeclared, and they can only be declared in builtin implicit
headers. The `__hlsl_resource_t` type represents a handle to a memory
resource and it is going to be used in builtin HLSL buffer types like this:
template <typename T>
class RWBuffer {
[[hlsl::contained_type(T)]]
[[hlsl::is_rov(false)]]
[[hlsl::resource_class(uav)]]
__hlsl_resource_t Handle;
};
Part 1/3 of llvm/llvm-project#90631.
---------
Co-authored-by: Justin Bogner <mail@justinbogner.com>
The builtin computes the discriminator for a type, which can be used to
sign/authenticate function pointers and member function pointers.
If the type passed to the builtin is a C++ member function pointer type,
the result is the discriminator used to signed member function pointers
of that type. If the type is a function, function pointer, or function
reference type, the result is the discriminator used to sign functions
of that type. It is ill-formed to use this builtin with any other type.
A call to this function is an integer constant expression.
Co-Authored-By: John McCall rjmccall@apple.com
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.
This reverts commit ce4aada6e2135e29839f672a6599db628b53295d and a
follow-up patch 8ef26f1289bf069ccc0d6383f2f4c0116a1206c1.
This new warning can not be fully suppressed by the
`-Wno-missing-dependent-template-keyword` flag, this gives developer no
time to do the cleanup in a large codebase, see https://github.com/llvm/llvm-project/pull/98547#issuecomment-2228250884
Reapplies #92957, fixing an instance where the `template` keyword was
missing prior to a dependent name in `llvm/ADT/ArrayRef.h`. An
_alias-declaration_ is used to work around a bug affecting GCC releases
before 11.1 (see https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94799) which
rejects the use of the `template` keyword prior to the
_nested-name-specifier_ in the class member access.
CWG1835 was one of the many core issues resolved by P1787R6: "Declarations and where to
find them" (http://wg21.link/p1787r6). Its resolution changes how
member-qualified names (as defined by [basic.lookup.qual.general] p2) are looked
up. This patch implementation that resolution.
Previously, an _identifier_ following `.` or `->` would be first looked
up in the type of the object expression (i.e. qualified lookup), and
then in the context of the _postfix-expression_ (i.e. unqualified
lookup) if nothing was found; the result of the second lookup was
required to name a class template. Notably, this second lookup would
occur even when the object expression was dependent, and its result
would be used to determine whether a `<` token is the start of a
_template-argument_list_.
The new wording in [basic.lookup.qual.general] p2 states:
> A member-qualified name is the (unique) component name, if any, of
> - an _unqualified-id_ or
> - a _nested-name-specifier_ of the form _`type-name ::`_ or
_`namespace-name ::`_
>
> in the id-expression of a class member access expression. A
***qualified name*** is
> - a member-qualified name or
> - the terminal name of
> - a _qualified-id_,
> - a _using-declarator_,
> - a _typename-specifier_,
> - a _qualified-namespace-specifier_, or
> - a _nested-name-specifier_, _elaborated-type-specifier_, or
_class-or-decltype_ that has a _nested-name-specifier_.
>
> The _lookup context_ of a member-qualified name is the type of its
associated object expression (considered dependent if the object
expression is type-dependent). The lookup context of any other qualified
name is the type, template, or namespace nominated by the preceding
_nested-name-specifier_.
And [basic.lookup.qual.general] p3 now states:
> _Qualified name lookup_ in a class, namespace, or enumeration performs
a search of the scope associated with it except as specified below.
Unless otherwise specified, a qualified name undergoes qualified name
lookup in its lookup context from the point where it appears unless the
lookup context either is dependent and is not the current instantiation
or is not a class or class template. If nothing is found by qualified
lookup for a member-qualified name that is the terminal name of a
_nested-name-specifier_ and is not dependent, it undergoes unqualified
lookup.
In non-standardese terms, these two paragraphs essentially state the
following:
- A name that immediately follows `.` or `->` in a class member access
expression is a member-qualified name
- A member-qualified name will be first looked up in the type of the
object expression `T` unless `T` is a dependent type that is _not_ the
current instantiation, e.g.
```
template<typename T>
struct A
{
void f(T* t)
{
this->x; // type of the object expression is 'A<T>'. although 'A<T>' is dependent, it is the
// current instantiation so we look up 'x' in the template definition context.
t->y; // type of the object expression is 'T' ('->' is transformed to '.' per [expr.ref]).
// 'T' is dependent and is *not* the current instantiation, so we lookup 'y' in the
// template instantiation context.
}
};
```
- If the first lookup finds nothing and:
- the member-qualified name is the first component of a
_nested-name-specifier_ (which could be an _identifier_ or a
_simple-template-id_), and either:
- the type of the object expression is the current instantiation and it
has no dependent base classes, or
- the type of the object expression is not dependent
then we lookup the name again, this time via unqualified lookup.
Although the second (unqualified) lookup is stated not to occur when the
member-qualified name is dependent, a dependent name will _not_ be
dependent once the template is instantiated, so the second lookup must
"occur" during instantiation if qualified lookup does not find anything.
This means that we must perform the second (unqualified) lookup during
parsing even when the type of the object expression is dependent, but
those results are _not_ used to determine whether a `<` token is the
start of a _template-argument_list_; they are stored so we can replicate
the second lookup during instantiation.
In even simpler terms (paraphrasing the meeting minutes from the review of P1787; see https://wiki.edg.com/bin/view/Wg21summer2020/P1787%28Lookup%29Review2020-06-15Through2020-06-18):
- Unqualified lookup always happens for the first name in a
_nested-name-specifier_ that follows `.` or `->`
- The result of that lookup is only used to determine whether `<` is the
start of a _template-argument-list_ if the first (qualified) lookup
found nothing and the lookup context:
- is not dependent, or
- is the current instantiation and has no dependent base classes.
An example:
```
struct A
{
void f();
};
template<typename T>
using B = A;
template<typename T>
struct C : A
{
template<typename U>
void g();
void h(T* t)
{
this->g<int>(); // ok, '<' is the start of a template-argument-list ('g' was found via qualified lookup in the current instantiation)
this->B<void>::f(); // ok, '<' is the start of a template-argument-list (current instantiation has no dependent bases, 'B' was found via unqualified lookup)
t->g<int>(); // error: '<' means less than (unqualified lookup does not occur for a member-qualified name that isn't the first component of a nested-name-specifier)
t->B<void>::f(); // error: '<' means less than (unqualified lookup does not occur if the name is dependent)
t->template B<void>::f(); // ok: '<' is the start of a template-argument-list ('template' keyword used)
}
};
```
Some additional notes:
- Per [basic.lookup.qual.general] p1, lookup for a
member-qualified name only considers namespaces, types, and templates
whose specializations are types if it's an _identifier_ followed by
`::`; lookup for the component name of a _simple-template-id_ followed
by `::` is _not_ subject to this rule.
- The wording which specifies when the second unqualified lookup occurs
appears to be paradoxical. We are supposed to do it only for the first
component name of a _nested-name-specifier_ that follows `.` or `->`
when qualified lookup finds nothing. However, when that name is followed
by `<` (potentially starting a _simple-template-id_) we don't _know_
whether it will be the start of a _nested-name-specifier_ until we do
the lookup -- but we aren't supposed to do the lookup until we know it's
part of a _nested-name-specifier_! ***However***, since we only do the
second lookup when the first lookup finds nothing (and the name isn't
dependent), ***and*** since neither lookup is type-only, the only valid
option is for the name to be the _template-name_ in a
_simple-template-id_ that is followed by `::` (it can't be an
_unqualified-id_ naming a member because we already determined that the
lookup context doesn't have a member with that name). Thus, we can lock
into the _nested-name-specifier_ interpretation and do the second lookup
without having to know whether the _simple-template-id_ will be followed
by `::` yet.
Virtual function pointer entries in v-tables are signed with address
discrimination in addition to declaration-based discrimination, where an
integer discriminator the string hash (see
`ptrauth_string_discriminator`) of the mangled name of the overridden
method. This notably provides diversity based on the full signature of
the overridden method, including the method name and parameter types.
This patch introduces ItaniumVTableContext logic to find the original
declaration of the overridden method.
On AArch64, these pointers are signed using the `IA` key (the
process-independent code key.)
V-table pointers can be signed with either no discrimination, or a
similar scheme using address and decl-based discrimination. In this
case, the integer discriminator is the string hash of the mangled
v-table identifier of the class that originally introduced the vtable
pointer.
On AArch64, these pointers are signed using the `DA` key (the
process-independent data key.)
Not using discrimination allows attackers to simply copy valid v-table
pointers from one object to another. However, using a uniform
discriminator of 0 does have positive performance and code-size
implications on AArch64, and diversity for the most important v-table
access pattern (virtual dispatch) is already better assured by the
signing schemas used on the virtual functions. It is also known that
some code in practice copies objects containing v-tables with `memcpy`,
and while this is not permitted formally, it is something that may be
invasive to eliminate.
This is controlled by:
```
-fptrauth-vtable-pointer-type-discrimination
-fptrauth-vtable-pointer-address-discrimination
```
In addition, this provides fine-grained controls in the
ptrauth_vtable_pointer attribute, which allows overriding the default
ptrauth schema for vtable pointers on a given class hierarchy, e.g.:
```
[[clang::ptrauth_vtable_pointer(no_authentication, no_address_discrimination,
no_extra_discrimination)]]
[[clang::ptrauth_vtable_pointer(default_key, default_address_discrimination,
custom_discrimination, 0xf00d)]]
```
The override is then mangled as a parametrized vendor extension:
```
"__vtptrauth" I
<key>
<addressDiscriminated>
<extraDiscriminator>
E
```
To support this attribute, this patch adds a small extension to the
attribute-emitter tablegen backend.
Note that there are known areas where signing is either missing
altogether or can be strengthened. Some will be addressed in later
changes (e.g., member function pointers, some RTTI).
`dynamic_cast` in particular is handled by emitting an artificial
v-table pointer load (in a way that always authenticates it) before the
runtime call itself, as the runtime doesn't have enough information
today to properly authenticate it. Instead, the runtime is currently
expected to strip the v-table pointer.
---------
Co-authored-by: John McCall <rjmccall@apple.com>
Co-authored-by: Ahmed Bougacha <ahmed@bougacha.org>
This commit implements the entirety of the now-accepted [N3017
-Preprocessor
Embed](https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3017.htm) and
its sister C++ paper [p1967](https://wg21.link/p1967). It implements
everything in the specification, and includes an implementation that
drastically improves the time it takes to embed data in specific
scenarios (the initialization of character type arrays). The mechanisms
used to do this are used under the "as-if" rule, and in general when the
system cannot detect it is initializing an array object in a variable
declaration, will generate EmbedExpr AST node which will be expanded by
AST consumers (CodeGen or constant expression evaluators) or expand
embed directive as a comma expression.
This reverts commit
682d461d5a.
---------
Co-authored-by: The Phantom Derpstorm <phdofthehouse@gmail.com>
Co-authored-by: Aaron Ballman <aaron@aaronballman.com>
Co-authored-by: cor3ntin <corentinjabot@gmail.com>
Co-authored-by: H. Vetinari <h.vetinari@gmx.com>
This patch adds a new builtin type for AMDGPU's buffer rsrc data type,
which is effectively an AS 8 pointer. This is needed because we'd like
to expose certain intrinsics to users via builtins which take buffer
rsrc as argument.
This commit implements the entirety of the now-accepted [N3017 -
Preprocessor
Embed](https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3017.htm) and
its sister C++ paper [p1967](https://wg21.link/p1967). It implements
everything in the specification, and includes an implementation that
drastically improves the time it takes to embed data in specific
scenarios (the initialization of character type arrays). The mechanisms
used to do this are used under the "as-if" rule, and in general when the
system cannot detect it is initializing an array object in a variable
declaration, will generate EmbedExpr AST node which will be expanded
by AST consumers (CodeGen or constant expression evaluators) or
expand embed directive as a comma expression.
---------
Co-authored-by: Aaron Ballman <aaron@aaronballman.com>
Co-authored-by: cor3ntin <corentinjabot@gmail.com>
Co-authored-by: H. Vetinari <h.vetinari@gmx.com>
Co-authored-by: Podchishchaeva, Mariya <mariya.podchishchaeva@intel.com>
OpenACC is going to need an array sections implementation that is a
simpler version/more restrictive version of the OpenMP version.
This patch moves `OMPArraySectionExpr` to `Expr.h` and renames it `ArraySectionExpr`,
then adds an enum to choose between the two.
This also fixes a couple of 'drive-by' issues that I discovered on the way,
but leaves the OpenACC Sema parts reasonably unimplemented (no semantic
analysis implementation), as that will be a followup patch.
HLSL constant sized array function parameters do not decay to pointers.
Instead constant sized array types are preserved as unique types for
overload resolution, template instantiation and name mangling.
This implements the change by adding a new `ArrayParameterType` which
represents a non-decaying `ConstantArrayType`. The new type behaves the
same as `ConstantArrayType` except that it does not decay to a pointer.
Values of `ConstantArrayType` in HLSL decay during overload resolution
via a new `HLSLArrayRValue` cast to `ArrayParameterType`.
`ArrayParamterType` values are passed indirectly by-value to functions
in IR generation resulting in callee generated memcpy instructions.
The behavior of HLSL function calls is documented in the [draft language
specification](https://microsoft.github.io/hlsl-specs/specs/hlsl.pdf)
under the Expr.Post.Call heading.
Additionally the design of this implementation approach is documented in
[Clang's
documentation](https://clang.llvm.org/docs/HLSL/FunctionCalls.html)
Resolves#70123
[RISCV] RISCV vector calling convention (1/2)
This is the vector calling convention based on
https://github.com/riscv-non-isa/riscv-elf-psabi-doc,
the idea is to split between "scalar" callee-saved registers
and "vector" callee-saved registers. "scalar" ones remain the
original strategy, however, "vector" ones are handled together
with RVV objects.
The stack layout would be:
|--------------------------| <-- FP
| callee-allocated save |
| area for register varargs|
|--------------------------|
| callee-saved registers | <-- scalar callee-saved
| (scalar) |
|--------------------------|
| RVV alignment padding |
|--------------------------|
| callee-saved registers | <-- vector callee-saved
| (vector) |
|--------------------------|
| RVV objects |
|--------------------------|
| padding before RVV |
|--------------------------|
| scalar local variables |
|--------------------------| <-- BP
| variable size objects |
|--------------------------| <-- SP
Note: This patch doesn't contain "tuple" type, e.g. vint32m1x2.
It will be handled in https://github.com/riscv-non-isa/riscv-elf-psabi-doc (2/2).
Differential Revision: https://reviews.llvm.org/D154576
In `-fbounds-safety`, bounds annotations are considered type attributes
rather than declaration attributes. Constructing them as type attributes
allows us to extend the attribute to apply nested pointers, which is
essential to annotate functions that involve out parameters: `void
foo(int *__counted_by(*out_count) *out_buf, int *out_count)`.
We introduce a new sugar type to support bounds annotated types,
`CountAttributedType`. In order to maintain extra data (the bounds
expression and the dependent declaration information) that is not
trackable in `AttributedType` we create a new type dedicate to this
functionality.
This patch also extends the parsing logic to parse the `counted_by`
argument as an expression, which will allow us to extend the model to
support arguments beyond an identifier, e.g., `__counted_by(n + m)` in
the future as specified by `-fbounds-safety`.
This also adjusts `__bdos` and array-bounds sanitizer code that already
uses `CountedByAttr` to check `CountAttributedType` instead to get the
field referred to by the attribute.
The new experimental calling convention preserve_none is the opposite
side of existing preserve_all. It tries to preserve as few general
registers as possible. So all general registers are caller saved
registers. It can also uses more general registers to pass arguments.
This attribute doesn't impact floating-point registers. Floating-point
registers still follow the c calling convention.
Currently preserve_none is supported on X86-64 only. It changes the c
calling convention in following fields:
* RSP and RBP are the only preserved general registers, all other
general registers are caller saved registers.
* We can use [RDI, RSI, RDX, RCX, R8, R9, R11, R12, R13, R14, R15, RAX]
to pass arguments.
It can improve the performance of hot tailcall chain, because many
callee saved registers' save/restore instructions can be removed if the
tail functions are using preserve_none. In my experiment in protocol
buffer, the parsing functions are improved by 3% to 10%.
Implements https://isocpp.org/files/papers/P2662R3.pdf
The feature is exposed as an extension in older language modes.
Mangling is not yet supported and that is something we will have to do before release.
Test updated to expect i8 gep.
Original message:
This adopts a similar behavior to AArch64 SVE, where bool vectors are
represented as a vector of chars with 1/8 the number of elements. This
ensures the vector always occupies a power of 2 number of bytes.
A consequence of this is that vbool64_t, vbool32_t, and vool16_t can
only be used with a vector length that guarantees at least 8 bits.
This adopts a similar behavior to AArch64 SVE, where bool vectors are
represented as a vector of chars with 1/8 the number of elements. This
ensures the vector always occupies a power of 2 number of bytes.
A consequence of this is that vbool64_t, vbool32_t, and vool16_t can
only be used with a vector length that guarantees at least 8 bits.
This is a follow up to https://github.com/llvm/llvm-project/pull/71417 ,
which aims to resolve concerns brought up there. Namely, this patch
replaces `CXXNewInitializationStyle::Implicit` with a dedicated
`HasInitializer` flag. This makes `CXXNewInitializationStyle` to model
syntax again. This patch also renames `Call` and `List` to less
confusing `Parens` and `Braces`.
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.
