///
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namespace arm_compute
{
namespace test
{
/**
@page tests Validation and benchmarks tests

@tableofcontents

@section tests_overview Overview

Benchmark and validation tests are based on the same framework to setup and run
the tests. In addition to running simple, self-contained test functions the
framework supports fixtures and data test cases. The former allows to share
common setup routines between various backends thus reducing the amount of
duplicated code. The latter can be used to parameterize tests or fixtures with
different inputs, e.g. different tensor shapes. One limitation is that
tests/fixtures cannot be parameterized based on the data type if static type
information is needed within the test (e.g. to validate the results).

@note By default tests are not built. To enable them you need to add validation_tests=1 and / or benchmark_tests=1 to your SCons line.

@note Tests are not included in the pre-built binary archive, you have to build them from sources.

@subsection tests_overview_structure Directory structure

    .
    `-- tests <- Top level test directory. All files in here are shared among validation and benchmark.
        |-- framework <- Underlying test framework.
        |-- CL             \
        |-- GLES_COMPUTE   \
        |-- NEON -> Backend specific files with helper functions etc.
        |-- benchmark <- Top level directory for the benchmarking files.
        |   |-- fixtures <- Fixtures for benchmark tests.
        |   |-- CL <- OpenCL backend test cases on a function level.
        |   |-- GLES_COMPUTE <- Same of OpenGL ES
        |   `-- NEON <- Same for NEON
        |-- datasets <- Datasets for benchmark and validation tests.
        |-- main.cpp <- Main entry point for the tests. Currently shared between validation and benchmarking.
        `-- validation -> Top level directory for validation files.
            |-- CPP -> C++ reference code
            |-- CL             \
            |-- GLES_COMPUTE   \
            |-- NEON -> Backend specific test cases
            `-- fixtures -> Fixtures shared among all backends. Used to setup target function and tensors.

@subsection tests_overview_fixtures Fixtures

Fixtures can be used to share common setup, teardown or even run tasks among
multiple test cases. For that purpose a fixture can define a `setup`,
`teardown` and `run` method. Additionally the constructor and destructor might
also be customized.

An instance of the fixture is created immediately before the actual test is
executed. After construction the @ref framework::Fixture::setup method is called. Then the test
function or the fixtures `run` method is invoked. After test execution the
@ref framework::Fixture::teardown method is called and lastly the fixture is destructed.

@subsubsection tests_overview_fixtures_fixture Fixture

Fixtures for non-parameterized test are straightforward. The custom fixture
class has to inherit from @ref framework::Fixture and choose to implement any of the
`setup`, `teardown` or `run` methods. None of the methods takes any arguments
or returns anything.

    class CustomFixture : public framework::Fixture
    {
        void setup()
        {
            _ptr = malloc(4000);
        }

        void run()
        {
            ARM_COMPUTE_ASSERT(_ptr != nullptr);
        }

        void teardown()
        {
            free(_ptr);
        }

        void *_ptr;
    };

@subsubsection tests_overview_fixtures_data_fixture Data fixture

The advantage of a parameterized fixture is that arguments can be passed to the setup method at runtime. To make this possible the setup method has to be a template with a type parameter for every argument (though the template parameter doesn't have to be used). All other methods remain the same.

    class CustomFixture : public framework::Fixture
    {
    #ifdef ALTERNATIVE_DECLARATION
        template <typename ...>
        void setup(size_t size)
        {
            _ptr = malloc(size);
        }
    #else
        template <typename T>
        void setup(T size)
        {
            _ptr = malloc(size);
        }
    #endif

        void run()
        {
            ARM_COMPUTE_ASSERT(_ptr != nullptr);
        }

        void teardown()
        {
            free(_ptr);
        }

        void *_ptr;
    };

@subsection tests_overview_test_cases Test cases

All following commands can be optionally prefixed with `EXPECTED_FAILURE_` or
`DISABLED_`.

@subsubsection tests_overview_test_cases_test_case Test case

A simple test case function taking no inputs and having no (shared) state.

- First argument is the name of the test case (has to be unique within the
  enclosing test suite).
- Second argument is the dataset mode in which the test will be active.


    TEST_CASE(TestCaseName, DatasetMode::PRECOMMIT)
    {
        ARM_COMPUTE_ASSERT_EQUAL(1 + 1, 2);
    }

@subsubsection tests_overview_test_cases_fixture_fixture_test_case Fixture test case

A simple test case function taking no inputs that inherits from a fixture. The
test case will have access to all public and protected members of the fixture.
Only the setup and teardown methods of the fixture will be used. The body of
this function will be used as test function.

- First argument is the name of the test case (has to be unique within the
  enclosing test suite).
- Second argument is the class name of the fixture.
- Third argument is the dataset mode in which the test will be active.


    class FixtureName : public framework::Fixture
    {
        public:
            void setup() override
            {
                _one = 1;
            }

        protected:
            int _one;
    };

    FIXTURE_TEST_CASE(TestCaseName, FixtureName, DatasetMode::PRECOMMIT)
    {
        ARM_COMPUTE_ASSERT_EQUAL(_one + 1, 2);
    }

@subsubsection tests_overview_test_cases_fixture_register_fixture_test_case Registering a fixture as test case

Allows to use a fixture directly as test case. Instead of defining a new test
function the run method of the fixture will be executed.

- First argument is the name of the test case (has to be unique within the
  enclosing test suite).
- Second argument is the class name of the fixture.
- Third argument is the dataset mode in which the test will be active.


    class FixtureName : public framework::Fixture
    {
        public:
            void setup() override
            {
                _one = 1;
            }

            void run() override
            {
                ARM_COMPUTE_ASSERT_EQUAL(_one + 1, 2);
            }

        protected:
            int _one;
    };

    REGISTER_FIXTURE_TEST_CASE(TestCaseName, FixtureName, DatasetMode::PRECOMMIT);


@subsubsection tests_overview_test_cases_data_test_case Data test case

A parameterized test case function that has no (shared) state. The dataset will
be used to generate versions of the test case with different inputs.

- First argument is the name of the test case (has to be unique within the
  enclosing test suite).
- Second argument is the dataset mode in which the test will be active.
- Third argument is the dataset.
- Further arguments specify names of the arguments to the test function. The
  number must match the arity of the dataset.


    DATA_TEST_CASE(TestCaseName, DatasetMode::PRECOMMIT, framework::make("Numbers", {1, 2, 3}), num)
    {
        ARM_COMPUTE_ASSERT(num < 4);
    }

@subsubsection tests_overview_test_cases_fixture_data_test_case Fixture data test case

A parameterized test case that inherits from a fixture. The test case will have
access to all public and protected members of the fixture. Only the setup and
teardown methods of the fixture will be used. The setup method of the fixture
needs to be a template and has to accept inputs from the dataset as arguments.
The body of this function will be used as test function. The dataset will be
used to generate versions of the test case with different inputs.

- First argument is the name of the test case (has to be unique within the
  enclosing test suite).
- Second argument is the class name of the fixture.
- Third argument is the dataset mode in which the test will be active.
- Fourth argument is the dataset.


    class FixtureName : public framework::Fixture
    {
        public:
            template <typename T>
            void setup(T num)
            {
                _num = num;
            }

        protected:
            int _num;
    };

    FIXTURE_DATA_TEST_CASE(TestCaseName, FixtureName, DatasetMode::PRECOMMIT, framework::make("Numbers", {1, 2, 3}))
    {
        ARM_COMPUTE_ASSERT(_num < 4);
    }

@subsubsection tests_overview_test_cases_register_fixture_data_test_case Registering a fixture as data test case

Allows to use a fixture directly as parameterized test case. Instead of
defining a new test function the run method of the fixture will be executed.
The setup method of the fixture needs to be a template and has to accept inputs
from the dataset as arguments. The dataset will be used to generate versions of
the test case with different inputs.

- First argument is the name of the test case (has to be unique within the
  enclosing test suite).
- Second argument is the class name of the fixture.
- Third argument is the dataset mode in which the test will be active.
- Fourth argument is the dataset.


    class FixtureName : public framework::Fixture
    {
        public:
            template <typename T>
            void setup(T num)
            {
                _num = num;
            }

            void run() override
            {
                ARM_COMPUTE_ASSERT(_num < 4);
            }

        protected:
            int _num;
    };

    REGISTER_FIXTURE_DATA_TEST_CASE(TestCaseName, FixtureName, DatasetMode::PRECOMMIT, framework::make("Numbers", {1, 2, 3}));

@section writing_tests Writing validation tests

Before starting a new test case have a look at the existing ones. They should
provide a good overview how test cases are structured.

- The C++ reference needs to be added to `tests/validation/CPP/`. The
  reference function is typically a template parameterized by the underlying
  value type of the `SimpleTensor`. This makes it easy to specialise for
  different data types.
- If all backends have a common interface it makes sense to share the setup
  code. This can be done by adding a fixture in
  `tests/validation/fixtures/`. Inside of the `setup` method of a fixture
  the tensors can be created and initialised and the function can be configured
  and run. The actual test will only have to validate the results. To be shared
  among multiple backends the fixture class is usually a template that accepts
  the specific types (data, tensor class, function class etc.) as parameters.
- The actual test cases need to be added for each backend individually.
  Typically the will be multiple tests for different data types and for
  different execution modes, e.g. precommit and nightly.

@section tests_running_tests Running tests
@subsection tests_running_tests_benchmark_and_validation Benchmarking and validation suites
@subsubsection tests_running_tests_benchmarking_filter Filter tests
All tests can be run by invoking

    ./arm_compute_benchmark ./data

where `./data` contains the assets needed by the tests.

If only a subset of the tests has to be executed the `--filter` option takes a
regular expression to select matching tests.

    ./arm_compute_benchmark --filter='^NEON/.*AlexNet' ./data

@note Filtering will be much faster if the regular expression starts from the start ("^") or end ("$") of the line.

Additionally each test has a test id which can be used as a filter, too.
However, the test id is not guaranteed to be stable when new tests are added.
Only for a specific build the same the test will keep its id.

    ./arm_compute_benchmark --filter-id=10 ./data

All available tests can be displayed with the `--list-tests` switch.

    ./arm_compute_benchmark --list-tests

More options can be found in the `--help` message.

@subsubsection tests_running_tests_benchmarking_runtime Runtime
By default every test is run once on a single thread. The number of iterations
can be controlled via the `--iterations` option and the number of threads via
`--threads`.

@subsubsection tests_running_tests_benchmarking_output Output
By default the benchmarking results are printed in a human readable format on
the command line. The colored output can be disabled via `--no-color-output`.
As an alternative output format JSON is supported and can be selected via
`--log-format=json`. To write the output to a file instead of stdout the
`--log-file` option can be used.

@subsubsection tests_running_tests_benchmarking_mode Mode
Tests contain different datasets of different sizes, some of which will take several hours to run.
You can select which datasets to use by using the `--mode` option, we recommed you use `--mode=precommit` to start with.

@subsubsection tests_running_tests_benchmarking_instruments Instruments
You can use the `--instruments` option to select one or more instruments to measure the execution time of the benchmark tests.

`PMU` will try to read the CPU PMU events from the kernel (They need to be enabled on your platform)

`MALI` will try to collect Mali hardware performance counters. (You need to have a recent enough Mali driver)

`WALL_CLOCK_TIMER` will measure time using `gettimeofday`: this should work on all platforms.

You can pass a combinations of these instruments: `--instruments=PMU,MALI,WALL_CLOCK_TIMER`

@note You need to make sure the instruments have been selected at compile time using the `pmu=1` or `mali=1` scons options.

@subsubsection tests_running_examples Examples

To run all the precommit validation tests:

	LD_LIBRARY_PATH=. ./arm_compute_validation --mode=precommit

To run the OpenCL precommit validation tests:

	LD_LIBRARY_PATH=. ./arm_compute_validation --mode=precommit --filter="^CL.*"

To run the NEON precommit benchmark tests with PMU and Wall Clock timer in miliseconds instruments enabled:

	LD_LIBRARY_PATH=. ./arm_compute_benchmark --mode=precommit --filter="^NEON.*" --instruments="pmu,wall_clock_timer_ms" --iterations=10

To run the OpenCL precommit benchmark tests with OpenCL kernel timers in miliseconds enabled:

	LD_LIBRARY_PATH=. ./arm_compute_benchmark --mode=precommit --filter="^CL.*" --instruments="opencl_timer_ms" --iterations=10

@note You might need to export the path to OpenCL library as well in your LD_LIBRARY_PATH if Compute Library was built with OpenCL enabled.
*/
} // namespace test
} // namespace arm_compute
