This reverts commit e1933a04 until I can look
into bot failures.

Return value of the system call was not returned normally.
It was discussed at https://reviews.llvm.org/D105169.

Newer GLIBC uses sysconf to get SIGSTKSZ.

This commit adds a new plugin, GDBJITDebugInfoRegistrationPlugin, that checks
for objects containing debug info and registers any debug info found via the
GDB JIT registration API.

To enable this registration without redundantly representing non-debug sections
this plugin synthesizes a new embedded object within a section of the LinkGraph.
An allocation action is used to make the registration call.

Currently MachO only. ELF users can still use the DebugObjectManagerPlugin. The
two are likely to be merged in the near future.

The if-check above deleted part guarantees that StoreOffset <= LoadOffset
and that StoreOffset + StoreSize >= LoadOffset + LoadSize, and given that
LoadOffset + LoadSize > LoadOffset when LoadSize > 0. Thus, this shows
StoreOffset + StoreSize > LoadOffset is guaranteed given LoadSize > 0,
while it could be meaningless to have a type with nonpositive size, so that
the check could be removed.

Part of revision D100179
Reviewed By: nikic

This reverts commit f0cf544d.

Just a small change to fix:

```
/home/buildbot/as-builder-4/llvm-clang-x86_64-expensive-checks-ubuntu/llvm-project/llvm/lib/Support/VirtualFileSystem.cpp: In static member function ‘static llvm::ErrorOr<std::unique_ptr<llvm::vfs::File> > llvm::vfs::File::getWithPath(llvm::ErrorOr<std::unique_ptr<llvm::vfs::File> >, const llvm::Twine&)’:
/home/buildbot/as-builder-4/llvm-clang-x86_64-expensive-checks-ubuntu/llvm-project/llvm/lib/Support/VirtualFileSystem.cpp:2084:10: error: could not convert ‘F’ from ‘std::unique_ptr<llvm::vfs::File>’ to ‘llvm::ErrorOr<std::unique_ptr<llvm::vfs::File> >’
   return F;
          ^
```

Differential Revision: https://reviews.llvm.org/D113832

Mostly replace uses of `container.size()` with `container.empty()` in
conditionals when applicable.

While here, unhide function-arg-placeholders flag. It's reasonable to want and
maybe we should consider making it default.

Fixes https://github.com/clangd/clangd/issues/922

Differential Revision: https://reviews.llvm.org/D113765

c17d9b4b added REQUIRES lines to a lot of Arm and AArch64
test, but added them to the very beginning, before the existing
update_cc_test_checks lines. This just moves them later so as to not
mess up the existing ordering when the checks are regenerated.

```
/work/omp-vega20-0/openmp-offload-amdgpu-runtime/llvm.src/llvm/lib/Support/VirtualFileSystem.cpp: In static member function 'static llvm::ErrorOr<std::unique_ptr<llvm::vfs::File> > llvm::vfs::File::getWithPath(llvm::ErrorOr<std::unique_ptr<llvm::vfs::File> >, const llvm::Twine&)':
/work/omp-vega20-0/openmp-offload-amdgpu-runtime/llvm.src/llvm/lib/Support/VirtualFileSystem.cpp:2084:10: error: could not convert 'F' from 'std::unique_ptr<llvm::vfs::File>' to 'llvm::ErrorOr<std::unique_ptr<llvm::vfs::File> >'
   return F;
          ^
```

This reverts commit c9721756.

D112904 fixed some code alignment issues, but it seems only line was
omitted. (Found while resolving merge conflicts for my own patches.)

This is a follow up to 0be9ca7c to make
paths in the case of falling back to the external file system use the
original format, preserving relative paths, and allow the external
filesystem to canonicalize them if needed.

Reviewed By: dexonsmith

Differential Revision: https://reviews.llvm.org/D109128

This reverts commit cef1e07c.

It broke the windows bot.

Regenerate with -NEXT checks to make a future diff clearer.

This patch rewrites checks in a few debug info tests to avoid using
'CHECK-NOT: {{DW_TAG|NULL}}'. It proposes `--impicit-check-not=DW_TAG`
instead, as it makes the checks clearer, and easier to analyze and update.

Differential Revision: https://reviews.llvm.org/D113652

https://bugs.llvm.org/show_bug.cgi?id=52228

For multilevel namespaces in C# get their content indented when NamespaceIndentation: None is set, where as single level namespaces are formatted correctly.

Reviewed By: HazardyKnusperkeks, jbcoe

Differential Revision: https://reviews.llvm.org/D112887

For AVX512 targets without VLX, we have to widen 128/256-bit vectors to 512-bits to use some specific AVX512 instructions (or some other instructions with predicates etc.).

I've pulled out the widening code from LowerFunnelShift into the helper function, so we can convert some other widening patterns in the future.

SCEVLoopGuardRewriter doesn't need to copy the rewrite map. It can just
hold a const reference instead, to avoid an unnecessary copy.

We used to mmap C++ shadow stack as part of the trace region
before ed7f3f5b ("tsan: move shadow stack into ThreadState"),
which moved the shadow stack into TLS. This started causing
timeouts and OOMs on some of our internal tests that repeatedly
create and destroy thousands of threads.
Allocate C++ shadow stack with mmap and small pages again.
This prevents the observed timeouts and OOMs.
But we now need to be more careful with interceptors that
run after thread finalization because FuncEntry/Exit and
TraceAddEvent all need the shadow stack.

Reviewed By: vitalybuka

Differential Revision: https://reviews.llvm.org/D113786

This reverts commit afafa883.

-pthread was not the fix. Symbols removed from GLIBC 2.34
Fixed with e60b3fce.

Reviewed By: pengfei

Differential Revision: https://reviews.llvm.org/D113817

Only search within the requested section, and allow one-past-then-end addresses.

This is needed to support section-end-address references to sections with no
symbols in them.

Change FileError to pass through the error code from the Error it wraps.
This allows APIs that return ECError to transition to FileError without
changing returned std::error_code.

This was extracted from https://reviews.llvm.org/D109345.

Differential Revision: https://reviews.llvm.org/D113225

Fix the const-ness of `iterator_facade_base::operator->` and
`iterator_facade_base::operator[]`. This is a follow-up to
1b651be0, which fixed const-ness of
various iterator adaptors.

Iterators, like the pointers that they generalize, have two types of
`const`.

  - The `const` qualifier on members indicates whether the iterator
    itself can be changed. This is analagous to `int *const`.
  - The `const` qualifier on return values of `operator*()`,
    `operator[]()`, and `operator->()` controls whether the the
    pointed-to value can be changed. This is analogous to `const int*`.

If an iterator facade returns a handle to its own state, then T (and
PointerT and ReferenceT) should usually be const-qualified. Otherwise,
if clients are expected to modify the state itself, the field can be
declared mutable or a const_cast can be used.

VarStreamArrayIterator returns a reference to a just-computed internal
value. Change it to iterate over `const ValueType` to avoid allowing
clients to mutate the internal state, and to drop the
non-`const`-qualified operator*().

The removed operator*() was from 175d70ee to get
iterator_facade_base::operator->() working, and this fixes the root
cause instead: setting `T` to `const ValueType` causes
iterator_facade_base to infer `PointerT` as `const ValueType*`.

Ironically, this is the last blocker for removing the const-incorrect
overload of `iterator_facade_base::operator->()`, whose presence
triggered adding the workaround in the first place :).

Differential Revision: https://reviews.llvm.org/D113797

Switch to using config.root.native_target to determine if tests are
supported.  This is a canonical form of the arch from the target
triple.

Reviewed By: lhames, DavidSpickett

Differential Revision: https://reviews.llvm.org/D110788

```
/Users/ksmiley/dev/llvm-project/lld/MachO/Symbols.cpp:43:27: warning: field 'external' will be initialized after field 'weakDefCanBeHidden' [-Wreorder-ctor]
      weakDef(isWeakDef), external(isExternal),
                          ^
1 warning generated.
```

Differential Revision: https://reviews.llvm.org/D113823

Previously this would crash. Fixes https://bugs.llvm.org/show_bug.cgi?id=51877

Differential Revision: https://reviews.llvm.org/D113819

autohide symbols behaves similarly to private_extern symbols.
However, LD64 allows exporting autohide symbols. LLD currently does not.
This patch allows LLD to export them.

Differential Revision: https://reviews.llvm.org/D113167

This implements the following changes:
* AutoType retains sugared deduced-as-type.
* Template argument deduction machinery analyses the sugared type all the way
down. It would previously lose the sugar on first recursion.
* Undeduced AutoType will be properly canonicalized, including the constraint
template arguments.
* Remove the decltype node created from the decltype(auto) deduction.

As a result, we start seeing sugared types in a lot more test cases,
including some which showed very unfriendly `type-parameter-*-*` types.

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Reviewed By: rsmith

Differential Revision: https://reviews.llvm.org/D110216

[X86][ABI] Change the alignment of f80 in 32-bit calling convention to meet with different data layout

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D113739

It fails to detect a single leak with GLIBC 2.34.

(Split from D113167)
Benchmarking on one of our large apps which exports a few thousands symbols,
this showed an improvement of ~17%.

x ./LLD_no_parallel.txt
+ ./LLD_with_parallel.txt

    N           Min           Max        Median           Avg        Stddev
x  10         84.01         89.41         88.64        87.693     1.7424061
+  10          71.9         74.29         72.63        72.753    0.77734663
Difference at 95.0% confidence
	-14.94 +/- 1.26763
	-17.0367% +/- 1.44553%
	(Student's t, pooled s = 1.34912)

(wallclock)

Differential Revision: https://reviews.llvm.org/D113820