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

[Vy Nguyen via llvm-commits]

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@@ -0,0 +1,651 @@
+//===- 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 be run in parellel, these should probably
+// be thread_local.
+static thread_local bool HasExitError = false;
+static thread_local std::string ExitMsg = "";
+static thread_local bool HasVendorConfig = false;
+static thread_local bool SanitizeData = false;
+static thread_local std::string Buffer = "";
+static thread_local std::vector<llvm::json::Object> EmittedJsons;
+static thread_local std::string ExpectedUuid = "";
+
+namespace llvm {
+namespace telemetry {
+namespace vendor_code {
+
+// Generate unique (but deterministic "uuid" for testing purposes).
+static std::string nextUuid() {
+  static std::atomic<int> seed = 1111;
+  return std::to_string(seed.fetch_add(1, std::memory_order_acquire));
+}
+
+struct VendorEntryKind {
+  // TODO: should avoid dup with other vendors' Types?
+  static const KindType VendorCommon = 0b010101000;
+  static const KindType Startup = 0b010101001;
+  static const KindType Exit = 0b010101010;
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oontvoo wrote:

It was supposed to be lined up, in which case, it was easier to see the difference (and the common bit, since the classof() needs to allow members of the sublcasses to pass for the base class, too)

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