src/base/coroutine.test.cc - public/gem5 - Git at Google

 /*
  * Copyright (c) 2018 ARM Limited
  * All rights reserved
  *
  * The license below extends only to copyright in the software and shall
  * not be construed as granting a license to any other intellectual
  * property including but not limited to intellectual property relating
  * to a hardware implementation of the functionality of the software
  * licensed hereunder.  You may use the software subject to the license
  * terms below provided that you ensure that this notice is replicated
  * unmodified and in its entirety in all distributions of the software,
  * modified or unmodified, in source code or in binary form.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met: redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer;
  * redistributions in binary form must reproduce the above copyright
  * notice, this list of conditions and the following disclaimer in the
  * documentation and/or other materials provided with the distribution;
  * neither the name of the copyright holders nor the names of its
  * contributors may be used to endorse or promote products derived from
  * this software without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */

 #include <gtest/gtest.h>

 #include "base/coroutine.hh"

 using namespace gem5;

 /**
  * This test is checking if the Coroutine, once it's created
  * it doesn't start since the second argument of the constructor
  * (run_coroutine) is set to false
  */
 TEST(Coroutine, Unstarted)
 {
     auto yielding_task =
     [] (Coroutine<void, void>::CallerType& yield)
     {
         yield();
     };

     const bool start_upon_creation = false;
     Coroutine<void, void> coro(yielding_task, start_upon_creation);

     ASSERT_FALSE(coro.started());
 }

 /**
  * This test is checking if the Coroutine, once it yields
  * back to the caller, it is still marked as not finished.
  */
 TEST(Coroutine, Unfinished)
 {
     auto yielding_task =
     [] (Coroutine<void, void>::CallerType& yield)
     {
         yield();
     };

     Coroutine<void, void> coro(yielding_task);
     ASSERT_TRUE(coro);
 }

 /**
  * This test is checking the parameter passing interface of a
  * coroutine which takes an integer as an argument.
  * Coroutine::operator() and CallerType::get() are the tested
  * APIS.
  */
 TEST(Coroutine, Passing)
 {
     const std::vector<int> input{ 1, 2, 3 };
     const std::vector<int> expected_values = input;

     auto passing_task =
     [&expected_values] (Coroutine<int, void>::CallerType& yield)
     {
         int argument;

         for (const auto expected : expected_values) {
             argument = yield.get();
             ASSERT_EQ(argument, expected);
         }
     };

     Coroutine<int, void> coro(passing_task);
     ASSERT_TRUE(coro);

     for (const auto val : input) {
         coro(val);
     }
 }

 /**
  * This test is checking the yielding interface of a coroutine
  * which takes no argument and returns integers.
  * Coroutine::get() and CallerType::operator() are the tested
  * APIS.
  */
 TEST(Coroutine, Returning)
 {
     const std::vector<int> output{ 1, 2, 3 };
     const std::vector<int> expected_values = output;

     auto returning_task =
     [&output] (Coroutine<void, int>::CallerType& yield)
     {
         for (const auto ret : output) {
             yield(ret);
         }
     };

     Coroutine<void, int> coro(returning_task);
     ASSERT_TRUE(coro);

     for (const auto expected : expected_values) {
         int returned = coro.get();
         ASSERT_EQ(returned, expected);
     }
 }

 /**
  * This test is still supposed to test the returning interface
  * of the the Coroutine, proving how coroutine can be used
  * for generators.
  * The coroutine is computing the first #steps of the fibonacci
  * sequence and it is yielding back results one number per time.
  */
 TEST(Coroutine, Fibonacci)
 {
     const std::vector<int> expected_values{
         1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233 };

     const int steps = expected_values.size();

     auto fibonacci_task =
     [steps] (Coroutine<void, int>::CallerType& yield)
     {
         int prev = 0;
         int current = 1;

         for (auto iter = 0; iter < steps; iter++) {
             int sum = prev + current;
             yield(sum);

             prev = current;
             current = sum;
         }
     };

     Coroutine<void, int> coro(fibonacci_task);
     ASSERT_TRUE(coro);

     for (const auto expected : expected_values) {
         ASSERT_TRUE(coro);
         int returned = coro.get();
         ASSERT_EQ(returned, expected);
     }
 }

 /**
  * This test is using a bi-channel coroutine (accepting and
  * yielding values) for testing a cooperative task.
  * The caller and the coroutine have a string each; they are
  * composing a new string by merging the strings together one
  * character per time.
  * The result string is hence passed back and forth between the
  * coroutine and the caller.
  */
 TEST(Coroutine, Cooperative)
 {
     const std::string caller_str("HloWrd");
     const std::string coro_str("el ol!");
     const std::string expected("Hello World!");

     auto cooperative_task =
     [&coro_str] (Coroutine<std::string, std::string>::CallerType& yield)
     {
         for (auto& appended_c : coro_str) {
             auto old_str = yield.get();
             yield(old_str + appended_c);
         }
     };

     Coroutine<std::string, std::string> coro(cooperative_task);

     std::string result;
     for (auto& c : caller_str) {
         ASSERT_TRUE(coro);
         result += c;
         result = coro(result).get();
     }

     ASSERT_EQ(result, expected);
 }

 /**
  * This test is testing nested coroutines by using one inner and one
  * outer coroutine. It basically ensures that yielding from the inner
  * coroutine returns to the outer coroutine (mid-layer of execution) and
  * not to the outer caller.
  */
 TEST(Coroutine, Nested)
 {
     const std::string wrong("Inner");
     const std::string expected("Inner + Outer");

     auto inner_task =
     [] (Coroutine<void, std::string>::CallerType& yield)
     {
         std::string inner_string("Inner");
         yield(inner_string);
     };

     auto outer_task =
     [&inner_task] (Coroutine<void, std::string>::CallerType& yield)
     {
         Coroutine<void, std::string> coro(inner_task);
         std::string inner_string = coro.get();

         std::string outer_string("Outer");
         yield(inner_string + " + " + outer_string);
     };


     Coroutine<void, std::string> coro(outer_task);
     ASSERT_TRUE(coro);

     std::string result = coro.get();

     ASSERT_NE(result, wrong);
     ASSERT_EQ(result, expected);
 }

 /**
  * This test is stressing the scenario where two distinct fibers are
  * calling the same coroutine.  First the test instantiates (and runs) a
  * coroutine, then spawns another one and it passes it a reference to
  * the first coroutine. Once the new coroutine calls the first coroutine
  * and the first coroutine yields, we are expecting execution flow to
  * be yielded to the second caller (the second coroutine) and not the
  * original caller (the test itself)
  */
 TEST(Coroutine, TwoCallers)
 {
     bool valid_return = false;

     Coroutine<void, void> callee{[]
         (Coroutine<void, void>::CallerType& yield)
     {
         yield();
         yield();
     }};

     Coroutine<void, void> other_caller{[&callee, &valid_return]
         (Coroutine<void, void>::CallerType& yield)
     {
         callee();
         valid_return = true;
         yield();
     }};

     ASSERT_TRUE(valid_return);
 }
	/*
	* Copyright (c) 2018 ARM Limited
	* All rights reserved
	*
	* The license below extends only to copyright in the software and shall
	* not be construed as granting a license to any other intellectual
	* property including but not limited to intellectual property relating
	* to a hardware implementation of the functionality of the software
	* licensed hereunder. You may use the software subject to the license
	* terms below provided that you ensure that this notice is replicated
	* unmodified and in its entirety in all distributions of the software,
	* modified or unmodified, in source code or in binary form.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions are
	* met: redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer;
	* redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution;
	* neither the name of the copyright holders nor the names of its
	* contributors may be used to endorse or promote products derived from
	* this software without specific prior written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
	* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
	* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	*/

	#include <gtest/gtest.h>

	#include "base/coroutine.hh"

	using namespace gem5;

	/**
	* This test is checking if the Coroutine, once it's created
	* it doesn't start since the second argument of the constructor
	* (run_coroutine) is set to false
	*/
	TEST(Coroutine, Unstarted)
	{
	auto yielding_task =
	[] (Coroutine<void, void>::CallerType& yield)
	{
	yield();
	};

	const bool start_upon_creation = false;
	Coroutine<void, void> coro(yielding_task, start_upon_creation);

	ASSERT_FALSE(coro.started());
	}

	/**
	* This test is checking if the Coroutine, once it yields
	* back to the caller, it is still marked as not finished.
	*/
	TEST(Coroutine, Unfinished)
	{
	auto yielding_task =
	[] (Coroutine<void, void>::CallerType& yield)
	{
	yield();
	};

	Coroutine<void, void> coro(yielding_task);
	ASSERT_TRUE(coro);
	}

	/**
	* This test is checking the parameter passing interface of a
	* coroutine which takes an integer as an argument.
	* Coroutine::operator() and CallerType::get() are the tested
	* APIS.
	*/
	TEST(Coroutine, Passing)
	{
	const std::vector<int> input{ 1, 2, 3 };
	const std::vector<int> expected_values = input;

	auto passing_task =
	[&expected_values] (Coroutine<int, void>::CallerType& yield)
	{
	int argument;

	for (const auto expected : expected_values) {
	argument = yield.get();
	ASSERT_EQ(argument, expected);
	}
	};

	Coroutine<int, void> coro(passing_task);
	ASSERT_TRUE(coro);

	for (const auto val : input) {
	coro(val);
	}
	}

	/**
	* This test is checking the yielding interface of a coroutine
	* which takes no argument and returns integers.
	* Coroutine::get() and CallerType::operator() are the tested
	* APIS.
	*/
	TEST(Coroutine, Returning)
	{
	const std::vector<int> output{ 1, 2, 3 };
	const std::vector<int> expected_values = output;

	auto returning_task =
	[&output] (Coroutine<void, int>::CallerType& yield)
	{
	for (const auto ret : output) {
	yield(ret);
	}
	};

	Coroutine<void, int> coro(returning_task);
	ASSERT_TRUE(coro);

	for (const auto expected : expected_values) {
	int returned = coro.get();
	ASSERT_EQ(returned, expected);
	}
	}

	/**
	* This test is still supposed to test the returning interface
	* of the the Coroutine, proving how coroutine can be used
	* for generators.
	* The coroutine is computing the first #steps of the fibonacci
	* sequence and it is yielding back results one number per time.
	*/
	TEST(Coroutine, Fibonacci)
	{
	const std::vector<int> expected_values{
	1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233 };

	const int steps = expected_values.size();

	auto fibonacci_task =
	[steps] (Coroutine<void, int>::CallerType& yield)
	{
	int prev = 0;
	int current = 1;

	for (auto iter = 0; iter < steps; iter++) {
	int sum = prev + current;
	yield(sum);

	prev = current;
	current = sum;
	}
	};

	Coroutine<void, int> coro(fibonacci_task);
	ASSERT_TRUE(coro);

	for (const auto expected : expected_values) {
	ASSERT_TRUE(coro);
	int returned = coro.get();
	ASSERT_EQ(returned, expected);
	}
	}

	/**
	* This test is using a bi-channel coroutine (accepting and
	* yielding values) for testing a cooperative task.
	* The caller and the coroutine have a string each; they are
	* composing a new string by merging the strings together one
	* character per time.
	* The result string is hence passed back and forth between the
	* coroutine and the caller.
	*/
	TEST(Coroutine, Cooperative)
	{
	const std::string caller_str("HloWrd");
	const std::string coro_str("el ol!");
	const std::string expected("Hello World!");

	auto cooperative_task =
	[&coro_str] (Coroutine<std::string, std::string>::CallerType& yield)
	{
	for (auto& appended_c : coro_str) {
	auto old_str = yield.get();
	yield(old_str + appended_c);
	}
	};

	Coroutine<std::string, std::string> coro(cooperative_task);

	std::string result;
	for (auto& c : caller_str) {
	ASSERT_TRUE(coro);
	result += c;
	result = coro(result).get();
	}

	ASSERT_EQ(result, expected);
	}

	/**
	* This test is testing nested coroutines by using one inner and one
	* outer coroutine. It basically ensures that yielding from the inner
	* coroutine returns to the outer coroutine (mid-layer of execution) and
	* not to the outer caller.
	*/
	TEST(Coroutine, Nested)
	{
	const std::string wrong("Inner");
	const std::string expected("Inner + Outer");

	auto inner_task =
	[] (Coroutine<void, std::string>::CallerType& yield)
	{
	std::string inner_string("Inner");
	yield(inner_string);
	};

	auto outer_task =
	[&inner_task] (Coroutine<void, std::string>::CallerType& yield)
	{
	Coroutine<void, std::string> coro(inner_task);
	std::string inner_string = coro.get();

	std::string outer_string("Outer");
	yield(inner_string + " + " + outer_string);
	};


	Coroutine<void, std::string> coro(outer_task);
	ASSERT_TRUE(coro);

	std::string result = coro.get();

	ASSERT_NE(result, wrong);
	ASSERT_EQ(result, expected);
	}

	/**
	* This test is stressing the scenario where two distinct fibers are
	* calling the same coroutine. First the test instantiates (and runs) a
	* coroutine, then spawns another one and it passes it a reference to
	* the first coroutine. Once the new coroutine calls the first coroutine
	* and the first coroutine yields, we are expecting execution flow to
	* be yielded to the second caller (the second coroutine) and not the
	* original caller (the test itself)
	*/
	TEST(Coroutine, TwoCallers)
	{
	bool valid_return = false;

	Coroutine<void, void> callee{[]
	(Coroutine<void, void>::CallerType& yield)
	{
	yield();
	yield();
	}};

	Coroutine<void, void> other_caller{[&callee, &valid_return]
	(Coroutine<void, void>::CallerType& yield)
	{
	callee();
	valid_return = true;
	yield();
	}};

	ASSERT_TRUE(valid_return);
	}