### 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>

The epoll_wait functions are syscall wrappers that were requested by
upstream users. This patch adds them, as well as their header and types.

The tests are currently incomplete since they require epoll_create to
properly test epoll_wait. That will be added in a followup patch since
this one is already very large.

The current implementation of DebugNames is _only_ using hashes to
compute the bucket number. Once inside the bucket, it reverts back to
string comparisons, even though not all hashes inside a bucket are
identical.

This commit changes the behavior so that we check the hash before
comparing strings. Such check is so important that it speeds up a simple
benchmark by 20%. In other words, the following expression evaluation
time goes from 1100ms to 850ms.

```
bin/lldb \
		--batch \
		-o "b CodeGenFunction::GenerateCode" \
		-o run \
		-o "expr Fn" \
		-- \
		clang++ -c -g test.cpp -o /dev/null &> output
```

(Note, these numbers are considering the usage of IDX_parent)

If the input is non-zero, this intrinsic should also return a non-zero
value.

The alignment is directly encoded in the attribute. There doesn't seem
to be a good reason to give the possible alignments a name.

ConstantExpr does not use HungOffUses. If we know that the Instruction
the Operator subclass can represent also does not use HungOffUses, we
can be more efficient than falling back to User::getOperand.

Enable the fusion of parallel loops also when the 1st loop contains
multiple write accesses to the same buffer, if the accesses are always
on the same indices.
Fix LIT test cases whose loops were not being fused.

Signed-off-by: Fabrizio Indirli <Fabrizio.Indirli@arm.com>

Number of threads will automatically be set to a good value

This PR fixes https://github.com/llvm/llvm-project/issues/79057 and
improves code generation for opaque pointers by replacing the culprit
SPIRVGlobalRegistry::getOpTypePointer() call with a more appropriate
SPIRVGlobalRegistry::getOrCreateSPIRVPointerType() call. The latter
function works together with the `DuplicatesTracker`
(`SPIRVGeneralDuplicatesTracker DT;` from `class SPIRVGlobalRegistry`)
to trace existence of previous definitions of opaque pointers. This
allows to produce just one `OpTypePointer` command for all identical
opaque pointers definitions and to return the very same type record for
subsequent `SPIRVGlobalRegistry::createSPIRVType()` invocations.

This PR alone improves code generation by producing a single needed
definition per all opaque pointers to i8 of the same address space
instead of multiple identical definitions produced before the patch.
From the root cause analysis of
https://github.com/llvm/llvm-project/issues/79057 we see also that this
PR resolves the problem of inconsistency between keeping multiple
instruction for identical opaque pointer types and just a single record
for all such instructions in the `DuplicatesTracker`, and so it also
resolves the issue with crashes on creation of a struct with opaque
pointer fields due to the fact that now such struct fields refer to the
same operand `<id>` having a required record in the data structure used
for dependencies analysis (see
https://github.com/llvm/llvm-project/issues/79057).

prevent undefined behaviour of SPIR-V Backend non-asserts builds when dealing with token type (#78437)

The goal of this PR is to fix the issue when use of token type in LLVM
intrinsic causes undefined behavior of SPIR-V Backend code generator
when assertions are disabled:
https://github.com/llvm/llvm-project/issues/78434

Among possible fix options, discussed in the
https://github.com/llvm/llvm-project/issues/78434 issue description, the
option to generate a meaningful error before execution arrives at the
`llvm_unreachable` call looks like a better solution for now, because
SPIR-V doesn't support token type anyway without additional extensions.

The PR is to generate a user-friendly error message and exit without
generating a stack dump when such a usage of token type was detected
that would lead to undefined behavior of SPIR-V Backend code generator.

The goal of this PR is to fix the issue of global unnamed variables
causing SPIR-V Backend code generation to crash:
https://github.com/llvm/llvm-project/issues/78278

The reason for the crash is that GlobalValue's getGlobalIdentifier()
would fail for unnamed global variable when trying to access the first
character of the name (see lib/IR/Globals.cpp:150). This leads to assert
in Debug and undefined behaviour in Release builds.

The proposed fix generates a name of an unnamed global variable as
__unnamed_<unsigned number>, in a style of similar existing LLVM
implementation (see lib/IR/Mangler.cpp:131). A new class member variable
is added into `SPIRVInstructionSelector` class to keep track of the
number we give to anonymous global values to generate the same name
every time when this is needed.

The patch adds a new LIT test with the smallest implementation of
reproducer ll code.

This PR adds lowering the reference to a function that returns a
procedure pointer. It also fixed intrinsic ASSOCIATED to take such
argument.

---------

Co-authored-by: jeanPerier <jperier@nvidia.com>

To build libc docs:
- Configure with `-DLLVM_ENABLE_SPHINX=ON -DLIBC_INCLUDE_DOCS=ON`
- Build with `ninja docs-libc-html`

After #75103, `MLPrgramTransforms` depends on `BufferizationDialect`.
Also fix an unrelated compile error in `GreedyPatternRewriteDriver.cpp`.
(This was not failing on CI. I may be running an old compiler locally.)

To share code for folding broadcast in #79761

Currently cast from FP to int is implemented by clamping on the min and
max
integer values in the floating-point domain and then converting to
integer. However, the max int values are often non representable in the
floating-point input type due to lack of mantissa bits.

This patch instead use a select acting on a compare against max int + 1
which is representable in floating-point. It also has a special lowering
for cases where the integer range is wider than the floating-point range
to clamp the infinite values.

This function is used in `jitlink-check` lines in LIT tests. In #78371 I
missed to swap initial instruction bytes for systems that store the
constants as big-endian.

This folded casts into `memref.transpose` without updating the result
type of the transpose op, which resulted in IR that failed to verify for
statically sized memrefs.

i.e.

```mlir
%cast = memref.cast %0 : memref<?x4xf32> to memref<?x?xf32>
%transpose = memref.transpose %cast : memref<?x?xf32> to memref<?x?xf32>
```

would fold to:

```mlir
// Fails verification:
%transpose = memref.transpose %cast : memref<?x4xf32> to memref<?x?xf32>
```

There is currently no lowering out of `ml_program` in the LLVM
repository. This change adds a lowering to `memref` so that it can be
lowered all the way to LLVM. This lowering was taken from the [reference
backend in
torch-mlir](https://github.com/llvm/torch-mlir/commit/f41695360019bde71d52ca7548944d5488779e12
).

I had tried implementing the `BufferizableOpInterface` for `ml_program`
instead of adding a new pass but that did not work because
`OneShotBufferize` does not visit module-level ops like
`ml_program.global`.

[clang-format] Support of TableGen tokens with unary operator like form, bang operators and numeric literals. (#78996)

Adds the support for tokens that have forms like unary operators.
- bang operators:  `!name`
- cond operator: `!cond`
- numeric literals: `+1`, `-1`
cond operator are one of bang operators but is distinguished because it has very specific syntax.

Summary:
This test was added to test the generated header. Unfortunately this
doesn't work if the header is never generated. Add a check to make sure
the user has included it in the list of headers.

There are assumptions of matching/consistent paths of execution under SPMD that allow to have pure collective communication operations.

'arm64ecpe' was chosen arbitrarily as gcc MinGW doesn't provide EC
support.

The 'gang' clause takes a 'gang-arg-list', which is one of three 'tag'
values, followed by either an 'int-expr' or a 'size-expr', both of which
we already have parsing functions for.

The optional tag values are only slightly complicated, as one is a
keyword (static), so mild modifications needed to be made for that.

I got tripped twice after: 7b462251
Let's at least mention these in the `Contributing.rst` doc.

This aligns std::deque with std::vector w.r.t. hardening checks. There's
probably more that can be done with iterators, but start with this.

This caught a bug with one of libc++'s tests. One of the erase calls in
asan_caterpillar.pass.cpp was a no-op because the iterators were in the
other order. (deque::erase happened to cleanly do nothing when the
distance is negative.)

Fixes #63809

Summary:
Recent patches have added some missing intrinsic functions NVPTX. This
patch gets rid of all the remaining uses of inline assembly. The one
change that wasn't directly replaced with a built-in was the `pack` and
`unpack` implementations. However, using the generic C implementation is
equivalent to the output SASS when run through PTXAS.

Change the implementation of getLastCalleeSavedAlias to use RegUnits
instead of register aliases. This is much faster on targets like AMDGPU
which define a very large number of overlapping register tuples.

No functional change intended. If PhysReg overlaps multiple CSRs then
getLastCalleeSavedAlias(PhysReg) could conceivably return a different
arbitrary one, but currently it is only used for some debug printing
anyway.

Differential Revision: https://reviews.llvm.org/D146734

Add custom combine to lower load <3 x i8> as the more efficient sequence
below:
   ldrb wX, [x0, #2]
   ldrh wY, [x0]
   orr wX, wY, wX, lsl #16
   fmov s0, wX

At the moment, there are almost no cases in which such vector operations
will be generated automatically. The motivating case is non-power-of-2
SLP vectorization: https://github.com/llvm/llvm-project/pull/77790

Adds unsafe-fp-math, no-infs-fp-math, no-nans-fp-math,
approx-func-fp-math, and no-signed-zeros-fp-math function attributes.

This allows code generators using the LLVMIR dialect to match the
codegen of Clang.

This patch fix connection for LLDB for remote gdb server running on
RISC-V.

You can test connection with OpenOCD or qemu-riscv64.