[llvm] annotate interfaces in llvm/ProfileData for DLL export (#142861)

## Purpose

This patch is one in a series of code-mods that annotate LLVM’s public
interface for export. This patch annotates the `llvm/ProfileData`
library. These 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).

The bulk of these changes were generated automatically using the
[Interface Definition Scanner (IDS)](https://github.com/compnerd/ids)
tool, followed formatting with `git clang-format`.

The following manual adjustments were also applied after running IDS on
Linux:
- Manually annotate the file
`llvm/include/llvm/ProfileData/InstrProfData.inc` because it is skipped
by IDS
- Add `LLVM_TEMPLATE_ABI` and `LLVM_EXPORT_TEMPLATE` to exported
instantiated templates.
- Add `LLVM_ABI_FRIEND` to friend member functions declared with
`LLVM_ABI`
- Add `LLVM_ABI` to a small number of symbols that require export but
are not declared in headers

## 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

1 files changed, 6 insertions, 4 deletions

diff --git a/llvm/unittests/ProfileData/MemProfTest.cpp b/llvm/unittests/ProfileData/MemProfTest.cpp
index 1dbafea..b57567e 100644
--- a/llvm/unittests/ProfileData/MemProfTest.cpp
+++ b/llvm/unittests/ProfileData/MemProfTest.cpp
@@ -19,16 +19,18 @@
 #include "llvm/ProfileData/MemProfData.inc"
 #include "llvm/ProfileData/MemProfRadixTree.h"
 #include "llvm/ProfileData/MemProfReader.h"
+#include "llvm/Support/Compiler.h"
 #include "llvm/Support/raw_ostream.h"
 #include "gmock/gmock.h"
 #include "gtest/gtest.h"
 
 #include <initializer_list>
 
-extern llvm::cl::opt<float> MemProfLifetimeAccessDensityColdThreshold;
-extern llvm::cl::opt<unsigned> MemProfAveLifetimeColdThreshold;
-extern llvm::cl::opt<unsigned> MemProfMinAveLifetimeAccessDensityHotThreshold;
-extern llvm::cl::opt<bool> MemProfUseHotHints;
+LLVM_ABI extern llvm::cl::opt<float> MemProfLifetimeAccessDensityColdThreshold;
+LLVM_ABI extern llvm::cl::opt<unsigned> MemProfAveLifetimeColdThreshold;
+LLVM_ABI extern llvm::cl::opt<unsigned>
+    MemProfMinAveLifetimeAccessDensityHotThreshold;
+LLVM_ABI extern llvm::cl::opt<bool> MemProfUseHotHints;
 
 namespace llvm {
 namespace memprof {