Co-authored-by: Zingam <zingam@outlook.com>

The buffer deallocation pass checks the IR ("operation preconditions")
to make sure that there is no IR that is unsupported. In such a case,
the pass signals a failure.

The pass now rejects all ops with unknown memory effects. We do not know
whether such an op allocates memory or not. Therefore, the buffer
deallocation pass does not know whether a deallocation op should be
inserted or not.

Memory effects are queried from the `MemoryEffectOpInterface` interface.
Ops that do not implement this interface but have the
`RecursiveMemoryEffects` trait do not have any side effects (apart from
the ones that their nested ops may have).

Unregistered ops are now rejected by the pass because they do not
implement the `MemoryEffectOpInterface` and neither do we know if they
have `RecursiveMemoryEffects` or not. All test cases that currently have
unregistered ops are updated to use registered ops.

Currently, if `CLANG_HAVE_LIBXML` is defined, and the version of libxml2
is above 2.12.0, there will be two warnings when building clang.

warning: initializing 'xmlErrorPtr' (aka 'struct _xmlError *') with an
expression of type 'const xmlError *' (aka 'const struct _xmlError *')
discards qualifiers

Since this commit

https://gitlab.gnome.org/GNOME/libxml2/-/commit/45470611b047db78106dcb2fdbd4164163c15ab7,
libxml2 makes cmlGetLastError return a const error. This patch follows
libxml2. Making the result a const pointer should be compatible with
versions before 2.12.0.

Tested on ArchLinux with libxml2 2.12.3 installed.

There is already a "block inserted" notification (in
`OpBuilder::Listener`), so there should also be a "block removed"
notification.

The purpose of this change is to make the listener API more mature.
There is currently a gap between what kind of IR changes can be made and
what IR changes can be listened to. At the moment, the only way to
inform listeners about "block removal" is to send a manual
`notifyOperationModified` for the parent op (e.g., by wrapping the
`eraseBlock(b)` method call in `updateRootInPlace(b->getParentOp())`).
This tells the listener that *something* has changed, but it is somewhat
of an API abuse.

nonlazybind is for declarations, not for definitions. We could test the
behavior, but the output would be misleading.

Introduce a new `argument-within-domain` category that covers cases
where the given arguments make it impossible to produce a correct result
(or create a valid object in case of constructors). While the incorrect
result doesn't create an immediate problem within the library (like e.g.
a null pointer dereference would), it always indicates a logic error in
user code and is highly likely to lead to a bug in the program once the
value is used.

Follow up to #78862

These tests control hardening mode with `ADDITIONAL_COMPILE_FLAGS`, and
always set modes which use on TRAP. So we don't need to check
`libcpp-hardening-mode=fast`, and they must always fail with the current
HWASAN implementation.

This reverts commit aa04d2b7.

Meant to push this to my fork and did not realize I was on main and not
a separate branch.

Prepare for -fno-plt implementation.

Implements parts of: `P2637R3` https://wg21.link/P2637R3
(https://eel.is/c++draft/variant.visit)

Implements:
`variant.visit()`
`variant.visit<R>()`

The tests are as close as possible to the non-member function.

To land after: https://github.com/llvm/llvm-project/pull/76268



---------

Co-authored-by: Zingam <zingam@outlook.com>

This patch disables the mlgo-utils tests on Windows builders. MLGO is
not currently supported on Windows.

These tests were failing as some of them look for specific file paths
and the path conventions are different between Linux and Windows.

This patch updates the paths in the PR labelling config for the MLGO
label. In particular, the path for the new mlgo-utils subfolder under
llvm/utils has been added and two other files that were missed in the
original introduction.

The library files in the new mlgo-utils utilities folder only depend on
absl.logging. The builtin Python logging library is a direct drop-in
replacement here, so we can just change the include and drop the test
dependency.

This test demonstrates template instantiation via the interpreter code.
In order to do that we can allocate the object on the stack and extend
its lifetime by boxing it into a clang::Value.

That avoids the subtle problem where we call the new operator on an
object only known to the interpreter and we cannot destroy it from
compiled code since there is not suitable facility in clang::Value yet.

That should resolve the asan issues that was reported in
llvm/llvm-project#76218.

Don't insert cast ops for ops in `vector.mask` region in
`VectorDropLeadUnitDim`.

… return type.

The behavior now is consistent with the non template version.
Enabled and updated old test.

The InlineOrder Heap stores a CallBase ptr and InlineHistoryID pair.
When running the `erase_if` method, InlineHistoryID is always returned
with 0. Instead, we should be retrieving it from the `InlineHistoryMap`
(similar to what is done in the `pop` implementation).

This change is completely harmless because no one is using
InlineHistoryID right now as part of the `erase_if` implementation which
is currently only used in the ModuleInliner.

The added test case has a loop that is versioned, which has a use of the
loop in an if block after the loop. The current code replaces all uses
of the loop with the new version If, but only if the parent blocks
match. As far as I can see it should be safe to replace all the uses,
then construct the result for the If with op.op.

Find object files in library search path just like Apple's linker, this
makes building with some older MacOS SDKs easier since clang runs with
`-lcrt1.10.6.o`

...in attempt to fix the FreeBSD CI.

I noticed that suddenly some tests in the latest PRs fail to compile on
FreeBSD (`SIGILL` and `SIGTRAP` not defined). This tries to resolve
the issue.

Co-authored-by: Zingam <zingam@outlook.com>

After #77883, `fast` mode uses TRAP, and HWASAN
replaces TRAP with abort or error exit code.

On a quick looks it should be possible to avoid doing
that in HWASAN, but historically this is convention for all
sanitizers. Changing this behavior may break existing
users.

Other sanitizers are not affected because they don't
install TRAP handlers by default. But if they do, they also
replace TRAP with abort/exit.

Fixes llvm/llvm-project#62904

`AlignArrayOfStructures: Left` combined with `SpacesInParentheses: true`
causes the first cell of every row to have 1 additional space.
We were only setting the first cell of the first row to be against the
left brace, now every row will be against the left brace.

When I implemented `condition_variable_any::wait`, I missed the most
important paragraph in the spec:

> The following wait functions will be notified when there is a stop
request on the passed stop_token.
> In that case the functions return immediately, returning false if the
predicate evaluates to false.

From
https://eel.is/c++draft/thread.condition#thread.condvarany.intwait-1.

Fixes #76807

There is no automatic labeling for the Extra Clang Tools, except
Clang-Tidy and ClangD.

Module documentation improvement: prebuilt module location can be directly fetched via CMake variable. (#78405)

CMake officially supports binary directory variable of installed
dependency using `FetchContent`. According to the current documentation,
it fetches `std` module and use its binary directory as hardcoded
string, `${CMAKE_BINARY_DIR}/_deps/std-build`, however it can be
replaced with `${std_BINARY_DIR}`.

Reference: https://cmake.org/cmake/help/latest/module/FetchContent.html