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

[James Henderson 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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jh7370 wrote:

I'd recommend against using binary literals, because they're incredibly hard to distinguish from one another by eye when written like this.

I don't think you need to worry about vendor types: vendor types will be defined in their downstream extensions, which shouldn't interfere with these unit tests. They can always pick values that don't clash, if there's a real issue.

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