In a previous commit, the llvm-config-defined macro
LLVM_ENABLE_DEBUGLOC_COVERAGE_TRACKING was renamed to
LLVM_ENABLE_DEBUGLOC_TRACKING_COVERAGE. One instance of this in Clang
remains unchanged; this patch renames it, and adds an explicit
llvm-config inclusion to ensure the define doesn't silently get removed.

NFC outside of coverage tracking builds, which we do not currently test.

Co-authored-by: Kazu Hirata <kazu@google.com>

## Purpose
This patch is one in a series of code-mods that annotate LLVM’s public
interface for export. This patch ensures a few `cl::opt` declarations
are properly annotated with `LLVM_ABI`. The annotations currently have
no meaningful impact on the LLVM build; however, they are a prerequisite
to support an LLVM Windows DLL (shared library) build.

## Background
This effort is tracked in #109483. Additional context is provided in
[this
discourse](https://discourse.llvm.org/t/psa-annotating-llvm-public-interface/85307),
and documentation for `LLVM_ABI` and related annotations is found in the
LLVM repo
[here](https://github.com/llvm/llvm-project/blob/main/llvm/docs/InterfaceExportAnnotations.rst).

## Overview
- Remove local `extern` declarations of `llvm::PrintPipelinePasses`
because it is already correctly declared with an `LLVM_ABI` annotation
in `llvm\Passes\PassBuilder.h`. Leaving these declarations results in a
gcc compile warning unless they are also annotated with `LLVM_ABI`.
- Similarly, remove local `extern` declarations of
`ProfileSummaryCutoffHot` and `UseContextLessSummary` from
`llvm/tools/llvm-profgen/ProfileGenerator.cpp` since they are declared
with `LLVM_ABI` in `llvm\ProfileData\ProfileCommon.h`.
- Explicitly annotate the extern declaration of `ProfileCorrelate` in
`clang/lib/CodeGen/BackendUtil.cpp` since it is not declared in a
header. The definition of `ProfileCorrelate` in
`llvm\lib\Transforms\Instrumentation\InstrProfiling.cpp` is already
annotated with `LLVM_ABI`.

## Validation
Local builds and tests to validate cross-platform compatibility. This
included llvm, clang, and lldb on the following configurations:

- Windows with MSVC
- Windows with Clang
- Linux with GCC
- Linux with Clang
- Darwin with Clang

This PR resubmits the changes from #136098, which was previously
reverted due to a build failure during the linking stage:

```
undefined reference to `llvm::DebugInfoCorrelate'  
undefined reference to `llvm::ProfileCorrelate'
```

The root cause was that `llvm/lib/Frontend/Driver/CodeGenOptions.cpp`
references symbols from the `Instrumentation` component, but the
`LINK_COMPONENTS` in the `llvm/lib/Frontend/CMakeLists.txt` for
`LLVMFrontendDriver` did not include it. As a result, linking failed in
configurations where these components were not transitively linked.

### Fix:

This updated patch explicitly adds `Instrumentation` to
`LINK_COMPONENTS` in the relevant `llvm/lib/Frontend/CMakeLists.txt`
file to ensure the required symbols are properly resolved.

---------

Co-authored-by: ict-ql <168183727+ict-ql@users.noreply.github.com>
Co-authored-by: Chyaka <52224511+liliumshade@users.noreply.github.com>
Co-authored-by: Tarun Prabhu <tarunprabhu@gmail.com>

When using `-fcs-generate-profile` with distributed thin-lto in the same
fashion we do for local thin-lto, we hit the following assertion:


https://github.com/llvm/llvm-project/blob/6041c745f32e8fd60ed24e29e7d919d8d1c87ca6/llvm/lib/Support/PGOOptions.cpp#L36

Using local thin-lto with LLD for MachO, we set the missing path
automatically to a default value: https://reviews.llvm.org/D151589. In
this fix we add the same behavior.

---------

Co-authored-by: Nuri Amari <nuriamari@fb.com>

Most of the recent development on the MemProfiler has been on the Use part. The instrumentation has been quite stable for a while. As the complexity of the use grows (with undrifting, diagnostics etc) I figured it would be good to separate these two implementations.

Reverts llvm/llvm-project#136098

This patch implements IR-based Profile-Guided Optimization support in
Flang through the following flags:

- `-fprofile-generate` for instrumentation-based profile generation

- `-fprofile-use=<dir>/file` for profile-guided optimization

Resolves #74216 (implements IR PGO support phase)

**Key changes:**

- Frontend flag handling aligned with Clang/GCC semantics

- Instrumentation hooks into LLVM PGO infrastructure

- LIT tests verifying:

    - Instrumentation metadata generation

    - Profile loading from specified path

    - Branch weight attribution (IR checks)

**Tests:**

- Added gcc-flag-compatibility.f90 test module verifying:

    -  Flag parsing boundary conditions

    -  IR-level profile annotation consistency

    -  Profile input path normalization rules

- SPEC2006 benchmark results will be shared in comments

For details on LLVM's PGO framework, refer to [Clang PGO
Documentation](https://clang.llvm.org/docs/UsersManual.html#profile-guided-optimization).

This implementation was developed by [XSCC Compiler
Team](https://github.com/orgs/OpenXiangShan/teams/xscc).

---------

Co-authored-by: ict-ql <168183727+ict-ql@users.noreply.github.com>
Co-authored-by: Tom Eccles <t@freedommail.info>

These are identified by misc-include-cleaner.  I've filtered out those
that break builds.  Also, I'm staying away from llvm-config.h,
config.h, and Compiler.h, which likely cause platform- or
compiler-specific build failures.

Normally -fsanitize-coverage=stack-depth inserts inline arithmetic to
update thread_local __sancov_lowest_stack. To support stack depth
tracking in the Linux kernel, which does not implement traditional
thread_local storage, provide the option to call a function instead.

This matches the existing "stackleak" implementation that is supported
in Linux via a GCC plugin. To make this coverage more performant, a
minimum estimated stack depth can be chosen to enable the callback mode,
skipping instrumentation of functions with smaller stacks.

With -fsanitize-coverage-stack-depth-callback-min set greater than 0,
the __sanitize_cov_stack_depth() callback will be injected when the
estimated stack depth is greater than or equal to the given minimum.