[llvm] [llvm][Support] Add ExponentialBackoff helper (PR #81206)

[Michael Spencer via llvm-commits]

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@@ -0,0 +1,31 @@
+//===- unittests/ExponentialBackoffTest.cpp -------------------------------===//
+//
+// 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/Support/ExponentialBackoff.h"
+#include "gtest/gtest.h"
+#include <chrono>
+
+using namespace llvm;
+using namespace std::chrono_literals;
+
+namespace {
+
+TEST(ExponentialBackoffTest, Timeout) {
+  auto Start = std::chrono::steady_clock::now();
+  // Use short enough times that this test runs quickly.
+  ExponentialBackoff Backoff(100ms, 1ms, 10ms);
+  do {
+  } while (Backoff.waitForNextAttempt());
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Bigcheese wrote:

Yeah, I was concerned about edge cases with virtual machines or other weirdness. I locally checked and it seemed reasonable. Thanks.

https://github.com/llvm/llvm-project/pull/81206