[llvm] [llvm]Add a simple Telemetry framework (PR #102323)

[Alina Sbirlea via llvm-commits]

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@@ -0,0 +1,678 @@
+//===- llvm/unittest/Telemetry/TelemetryTest.cpp - Telemetry unittests ---===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Telemetry/Telemetry.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/IR/Constants.h"
+#include "llvm/IR/DataLayout.h"
+#include "llvm/IR/DebugInfoMetadata.h"
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/Module.h"
+#include "llvm/Support/Casting.h"
+#include "llvm/Support/Error.h"
+#include "llvm/Support/JSON.h"
+#include "llvm/Support/SourceMgr.h"
+#include "llvm/Support/raw_ostream.h"
+#include "gtest/gtest.h"
+#include <chrono>
+#include <ctime>
+#include <vector>
+
+// Testing parameters.
+// These are set by each test to force certain outcomes.
+// Since the tests may run in parallel, each test will have
+// its own TestContext populated.
+struct TestContext {
+  // Controlling whether there should be an Exit error (if so, what the
+  // expected exit message/description should be).
+  bool HasExitError = false;
+  std::string ExitMsg = "";
+
+  // Controllilng whether there is a vendor-provided config for
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alinas wrote:

```suggestion
  // Controlling whether there is a vendor-provided config for
```

https://github.com/llvm/llvm-project/pull/102323