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diff --git a/include/internal/benchmark/detail/catch_run_for_at_least.hpp b/include/internal/benchmark/detail/catch_run_for_at_least.hpp
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+++ b/include/internal/benchmark/detail/catch_run_for_at_least.hpp
@@ -0,0 +1,65 @@
+/*
+ *  Created by Joachim on 16/04/2019.
+ *  Adapted from donated nonius code.
+ *
+ *  Distributed under the Boost Software License, Version 1.0. (See accompanying
+ *  file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+ */
+
+// Run a function for a minimum amount of time
+
+#ifndef TWOBLUECUBES_CATCH_RUN_FOR_AT_LEAST_HPP_INCLUDED
+#define TWOBLUECUBES_CATCH_RUN_FOR_AT_LEAST_HPP_INCLUDED
+
+#include "../catch_clock.hpp"
+#include "../catch_chronometer.hpp"
+#include "catch_measure.hpp"
+#include "catch_complete_invoke.hpp"
+#include "catch_timing.hpp"
+#include "../../catch_meta.hpp"
+
+#include <utility>
+#include <type_traits>
+
+namespace Catch {
+    namespace Benchmark {
+        namespace Detail {
+            template <typename Clock, typename Fun>
+            TimingOf<Clock, Fun(int)> measure_one(Fun&& fun, int iters, std::false_type) {
+                return Detail::measure<Clock>(fun, iters);
+            }
+            template <typename Clock, typename Fun>
+            TimingOf<Clock, Fun(Chronometer)> measure_one(Fun&& fun, int iters, std::true_type) {
+                Detail::ChronometerModel<Clock> meter;
+                auto&& result = Detail::complete_invoke(fun, Chronometer(meter, iters));
+
+                return { meter.elapsed(), std::move(result), iters };
+            }
+
+            template <typename Clock, typename Fun>
+            using run_for_at_least_argument_t = typename std::conditional<is_callable<Fun(Chronometer)>::value, Chronometer, int>::type;
+
+            struct optimized_away_error : std::exception {
+                const char* what() const noexcept override {
+                    return "could not measure benchmark, maybe it was optimized away";
+                }
+            };
+
+            template <typename Clock, typename Fun>
+            TimingOf<Clock, Fun(run_for_at_least_argument_t<Clock, Fun>)> run_for_at_least(ClockDuration<Clock> how_long, int seed, Fun&& fun) {
+                auto iters = seed;
+                while (iters < (1 << 30)) {
+                    auto&& Timing = measure_one<Clock>(fun, iters, is_callable<Fun(Chronometer)>());
+
+                    if (Timing.elapsed >= how_long) {
+                        return { Timing.elapsed, std::move(Timing.result), iters };
+                    }
+                    iters *= 2;
+                }
+                throw optimized_away_error{};
+            }
+        } // namespace Detail
+    } // namespace Benchmark
+} // namespace Catch
+
+#endif // TWOBLUECUBES_CATCH_RUN_FOR_AT_LEAST_HPP_INCLUDED