import math
import tempfile
import unittest
from itertools import repeat

import torch
import torch.cuda
import torch.cuda.comm as comm

from common import TestCase, get_gpu_type, to_gpu, freeze_rng_state, run_tests

if not torch.cuda.is_available():
    print('CUDA not available, skipping tests')
    import sys
    sys.exit()


def is_floating(t):
    return type(t) in [torch.FloatTensor, torch.DoubleTensor,
                       torch.cuda.FloatTensor, torch.cuda.DoubleTensor]

types = [
    torch.FloatTensor,
    torch.DoubleTensor,
    torch.LongTensor,
    torch.IntTensor,
    torch.ShortTensor,
    torch.CharTensor,
    torch.ByteTensor,
]

float_types = [
    torch.FloatTensor,
    torch.DoubleTensor
]  # TODO: add half...


def number(floating, integer, t):
    name = type(t).__name__
    if 'Double' in name or 'Float' in name or 'Half' in name:
        return floating
    else:
        return integer
# TODO: check HalfTensor

S = 10
M = 50


def make_tensor(t, *sizes):
    return t(*sizes).copy_(torch.randn(*sizes))


def small_2d(t):
    return make_tensor(t, S, S)


def small_2d_scaled(t, scale=10):
    return make_tensor(t, S, S).mul(scale)


def small_3d(t):
    return make_tensor(t, S, S, S)


def medium_1d(t):
    return make_tensor(t, M)


def medium_2d(t):
    return make_tensor(t, M, M)


def medium_2d_scaled(t, scale=10):
    return make_tensor(t, M, M).mul(scale)


def small_3d_ones(t):
    return t(S, S, S).copy_(torch.ones(S, S, S))


def small_3d_positive(t):
    min_val = 1e-3 if is_floating(t) else 2
    return make_tensor(t, S, S, S).clamp_(min_val, 120)


def small_3d_unique(t):
    return t(S, S, S).copy_(torch.range(1, S * S * S))


def small_1d_lapack(t):
    return t(1, 3).copy_(torch.range(1, 3).view(3))


def small_2d_lapack(t):
    return t(3, 3).copy_(torch.range(1, 9).view(3, 3))


def small_2d_lapack_skinny(t):
    return t(3, 4).copy_(torch.range(1, 12).view(3, 4))


def small_2d_lapack_fat(t):
    return t(4, 3).copy_(torch.range(1, 12).view(4, 3))


def new_t(*sizes):
    def tmp(t):
        return t(*sizes).copy_(torch.randn(*sizes))
    return tmp

tests = [
    ('add', small_3d, lambda t: [number(3.14, 3, t)]),
    ('add', small_3d, lambda t: [small_3d_positive(t)], 'tensor'),
    ('add', small_3d, lambda t: [number(0.2, 2, t), small_3d_positive(t)], 'scalar_tensor'),
    ('sub', small_3d, lambda t: [number(3.14, 3, t)],),
    ('sub', small_3d, lambda t: [small_3d_positive(t)], 'tensor'),
    ('mul', small_3d, lambda t: [number(3.14, 3, t)],),
    ('mul', small_3d, lambda t: [small_3d_positive(t)], 'tensor'),
    ('div', small_3d, lambda t: [number(3.14, 3, t)],),
    ('div', small_3d, lambda t: [small_3d_positive(t)], 'tensor'),
    ('pow', small_3d, lambda t: [number(3.14, 3, t)], None, float_types),
    ('pow', small_3d, lambda t: [small_3d(t).abs_()], 'tensor', float_types),
    ('addbmm', small_2d, lambda t: [small_3d(t), small_3d(t)], None, float_types),
    ('addbmm', small_2d, lambda t: [number(0.4, 2, t), small_3d(t), small_3d(t)], 'scalar'),
    ('addbmm', small_2d, lambda t: [number(0.5, 3, t), number(0.4, 2, t), small_3d(t), small_3d(t)], 'two_scalars'),
    ('baddbmm', small_3d, lambda t: [small_3d(t), small_3d(t)],),
    ('baddbmm', small_3d, lambda t: [number(0.4, 2, t), small_3d(t), small_3d(t)], 'scalar'),
    ('baddbmm', small_3d, lambda t: [number(0.5, 3, t), number(0.4, 2, t), small_3d(t), small_3d(t)], 'two_scalars'),
    ('addcdiv', small_2d_lapack, lambda t: [small_2d_lapack(t).mul(2), small_2d_lapack(t)],),
    ('addcdiv', small_2d_lapack, lambda t: [number(2.8, 1, t),
                                            small_2d_lapack(t).mul(2), small_2d_lapack(t)], 'scalar'),
    ('addcmul', small_3d, lambda t: [small_3d(t), small_3d(t)],),
    ('addcmul', small_3d, lambda t: [number(0.4, 2, t), small_3d(t), small_3d(t)], 'scalar'),
    ('addmm', medium_2d, lambda t: [medium_2d(t), medium_2d(t)],),
    ('addmm', medium_2d, lambda t: [number(0.4, 2, t), medium_2d(t), medium_2d(t)], 'scalar'),
    ('addmm', medium_2d, lambda t: [number(0.5, 3, t), number(0.4, 2, t), medium_2d(t), medium_2d(t)], 'two_scalars'),
    ('addmv', medium_1d, lambda t: [medium_2d(t), medium_1d(t)],),
    ('addmv', medium_1d, lambda t: [number(0.4, 2, t), medium_2d(t), medium_1d(t)], 'scalar'),
    ('addmv', medium_1d, lambda t: [number(0.5, 3, t), number(0.4, 2, t), medium_2d(t), medium_1d(t)], 'two_scalars'),
    ('addr', medium_2d, lambda t: [medium_1d(t), medium_1d(t)],),
    ('addr', medium_2d, lambda t: [number(0.4, 2, t), medium_1d(t), medium_1d(t)], 'scalar'),
    ('addr', medium_2d, lambda t: [number(0.5, 3, t), number(0.4, 2, t), medium_1d(t), medium_1d(t)], 'two_scalars'),
    ('atan2', medium_2d, lambda t: [medium_2d(t)], None, float_types),
    ('fmod', small_3d, lambda t: [3], 'value'),
    ('fmod', small_3d, lambda t: [small_3d_positive(t)], 'tensor'),
    ('chunk', medium_2d, lambda t: [4],),
    ('chunk', medium_2d, lambda t: [4, 1], 'dim'),
    ('clamp', medium_2d_scaled, lambda t: [-1, 5],),
    ('clone', medium_2d, lambda t: [],),
    ('contiguous', medium_2d, lambda t: [],),
    ('cross', new_t(M, 3, M), lambda t: [new_t(M, 3, M)(t)],),
    ('cumprod', small_3d, lambda t: [1],),
    ('cumsum', small_3d, lambda t: [1],),
    ('dim', small_3d, lambda t: [],),
    ('dist', small_2d, lambda t: [small_2d(t)],),
    ('dist', small_2d, lambda t: [small_2d(t), 3], '3_norm'),
    ('dist', small_2d, lambda t: [small_2d(t), 2.5], '2_5_norm'),
    ('dot', medium_1d, lambda t: [medium_1d(t)],),
    ('element_size', medium_1d, lambda t: [],),
    ('eq', small_3d_ones, lambda t: [small_3d(t)],),
    ('eq', small_3d_ones, lambda t: [small_3d_ones(t)], 'equal'),
    ('ne', small_3d_ones, lambda t: [small_3d(t)],),
    ('ne', small_3d_ones, lambda t: [small_3d_ones(t)], 'equal'),
    ('equal', small_3d_ones, lambda t: [small_3d_ones(t)], 'equal'),
    ('equal', small_3d_ones, lambda t: [small_3d(t)],),
    ('expand', new_t(M, 1, M), lambda t: [M, 4, M],),
    ('expand_as', new_t(M, 1, M), lambda t: [new_t(M, 4, M)(t)],),
    ('fill', medium_2d, lambda t: [number(3.14, 3, t)],),
    ('ge', medium_2d, lambda t: [medium_2d(t)],),
    ('le', medium_2d, lambda t: [medium_2d(t)],),
    ('gt', medium_2d, lambda t: [medium_2d(t)],),
    ('lt', medium_2d, lambda t: [medium_2d(t)],),
    ('is_contiguous', medium_2d, lambda t: [],),
    # TODO: can't check negative case - GPU copy will be contiguous
    ('is_same_size', medium_2d, lambda t: [small_3d(t)], 'negative'),
    ('is_same_size', medium_2d, lambda t: [medium_2d(t)], 'positive'),
    ('is_set_to', medium_2d, lambda t: [medium_2d(t)],),
    # TODO: positive case
    ('kthvalue', small_3d_unique, lambda t: [3],),
    ('kthvalue', small_3d_unique, lambda t: [3, 1], 'dim'),
    ('lerp', small_3d, lambda t: [small_3d(t), 0.3],),
    ('max', small_3d_unique, lambda t: [],),
    ('max', small_3d_unique, lambda t: [1], 'dim'),
    ('max', medium_2d, lambda t: [medium_2d(t)], 'elementwise'),
    ('min', small_3d_unique, lambda t: [],),
    ('min', small_3d_unique, lambda t: [1], 'dim'),
    ('min', medium_2d, lambda t: [medium_2d(t)], 'elementwise'),
    ('mean', small_3d, lambda t: [],),
    ('mean', small_3d, lambda t: [1], 'dim'),
    ('mode', small_3d, lambda t: [],),
    ('mode', small_3d, lambda t: [1], 'dim'),
    ('remainder', small_3d, lambda t: [3], 'value'),
    ('remainder', small_3d, lambda t: [small_3d_positive(t)], 'tensor'),
    ('std', small_3d, lambda t: [],),
    ('std', small_3d, lambda t: [1], 'dim'),
    ('var', small_3d, lambda t: [],),
    ('var', small_3d, lambda t: [1], 'dim'),
    ('ndimension', small_3d, lambda t: [],),
    ('nelement', small_3d, lambda t: [],),
    ('numel', small_3d, lambda t: [],),
    ('narrow', small_3d, lambda t: [1, 3, 2],),
    ('nonzero', small_3d, lambda t: [],),
    ('norm', small_3d, lambda t: [],),
    ('norm', small_3d, lambda t: [3], '3_norm'),
    ('norm', small_3d, lambda t: [3, 0], '3_norm_dim'),
    ('ones', small_3d, lambda t: [1, 2, 3, 4, 5],),
    ('permute', new_t(1, 2, 3, 4), lambda t: [2, 1, 3, 0],),
    ('prod', small_3d, lambda t: [],),
    ('prod', small_3d, lambda t: [1], 'dim'),
    ('sum', small_2d, lambda t: [],),
    ('sum', small_3d, lambda t: [1], 'dim'),
    ('renorm', small_3d, lambda t: [2, 1, 1], '2_norm'),
    ('renorm', small_3d, lambda t: [1.5, 1, 1], '1_5_norm'),
    ('repeat', small_2d, lambda t: [2, 2, 2],),
    ('size', new_t(1, 2, 3, 4), lambda t: [],),
    ('sort', small_3d_unique, lambda t: [],),
    ('sort', small_3d_unique, lambda t: [1], 'dim'),
    ('sort', small_3d_unique, lambda t: [1, True], 'dim_descending'),
    ('split', small_3d, lambda t: [2],),
    ('split', small_3d, lambda t: [2, 1], 'dim'),
    ('squeeze', new_t(1, 2, 1, 4), lambda t: [],),
    ('squeeze', new_t(1, 2, 1, 4), lambda t: [2], 'dim'),
    ('t', new_t(1, 2), lambda t: [],),
    ('transpose', new_t(1, 2, 3, 4), lambda t: [1, 2],),
    ('to_list', small_3d, lambda t: [],),
    ('topk', small_3d, lambda t: [2, 1, False, True], 'dim_sort'),
    ('topk', small_3d, lambda t: [2, 1, True, True], 'dim_desc_sort'),
    ('trace', medium_2d, lambda t: [],),
    ('tril', medium_2d, lambda t: [],),
    ('tril', medium_2d, lambda t: [2], 'positive'),
    ('tril', medium_2d, lambda t: [-2], 'negative'),
    ('triu', medium_2d, lambda t: [],),
    ('triu', medium_2d, lambda t: [2], 'positive'),
    ('triu', medium_2d, lambda t: [-2], 'negative'),
    ('view', small_3d, lambda t: [100, 10],),
    ('view_as', small_3d, lambda t: [t(100, 10)],),
    ('zero', small_3d, lambda t: [],),
    ('zeros', small_3d, lambda t: [1, 2, 3, 4],),
    ('rsqrt', lambda t: small_3d(t) + 1, lambda t: [], None, float_types),
    ('sinh', lambda t: small_3d(t).clamp(-1, 1), lambda t: [], None, float_types),
    ('tan', lambda t: small_3d(t).clamp(-1, 1), lambda t: [], None, float_types),
    # lapack tests
    ('qr', small_2d_lapack, lambda t: [], 'square', float_types),
    ('qr', small_2d_lapack_skinny, lambda t: [], 'skinny', float_types),
    ('qr', small_2d_lapack_fat, lambda t: [], 'fat', float_types),

]

# TODO: random functions, cat, gather, scatter, index*, masked*,
#       resize, resizeAs, storage_offset, storage, stride, unfold

custom_precision = {
    'addbmm': 1e-4,
    'addmm': 1e-4,
    'addmv': 1e-4,
    'addr': 1e-4,
    'baddbmm': 1e-4,
    'rsqrt': 1e-4,
    'cumprod': 1e-4,
}

simple_pointwise = [
    'abs',
    'sign',
]
for fn in simple_pointwise:
    tests.append((fn, small_3d, lambda t: []))

simple_pointwise_float = [
    'log',
    'log1p',
    'sigmoid',
    'sin',
    'sqrt',
    'tanh',
    'acos',
    'asin',
    'atan',
    'cos',
    'cosh',
    'exp',
    'reciprocal',
    'floor',
    'frac',
    'neg',
    'round',
    'trunc',
    'ceil',
]

for fn in simple_pointwise_float:
    tests.append((fn, small_3d, lambda t: [], None, float_types))

_cycles_per_ms = None


def get_cycles_per_ms():
    """Approximate number of cycles per millisecond for torch.cuda._sleep"""
    global _cycles_per_ms
    if _cycles_per_ms is None:
        start = torch.cuda.Event(enable_timing=True)
        end = torch.cuda.Event(enable_timing=True)
        start.record()
        torch.cuda._sleep(1000000)
        end.record()
        end.synchronize()
        _cycles_per_ms = 1000000 / start.elapsed_time(end)
    return _cycles_per_ms


def compare_cpu_gpu(tensor_constructor, arg_constructor, fn, t, precision=1e-5):
    def tmp(self):
        cpu_tensor = tensor_constructor(t)
        gpu_tensor = to_gpu(cpu_tensor)
        cpu_args = arg_constructor(t)
        gpu_args = [to_gpu(arg) for arg in cpu_args]
        cpu_result = getattr(cpu_tensor, fn)(*cpu_args)
        try:
            gpu_result = getattr(gpu_tensor, fn)(*gpu_args)
        except RuntimeError as e:
            reason = e.args[0]
            if 'unimplemented data type' in reason:
                raise unittest.SkipTest('unimplemented data type')
            raise
        except AttributeError as e:
            reason = e.args[0]
            if 'object has no attribute' in reason:
                raise unittest.SkipTest('unimplemented data type')
            raise
        # If one changes, another should change as well
        self.assertEqual(cpu_tensor, gpu_tensor, precision)
        self.assertEqual(cpu_args, gpu_args, precision)
        # Compare results
        self.assertEqual(cpu_result, gpu_result, precision)
    return tmp


class TestCuda(TestCase):

    def test_autogpu(self):
        if torch.cuda.device_count() > 1:
            x = torch.randn(5, 5).cuda()
            y = torch.randn(5, 5).cuda()
            self.assertEqual(x.get_device(), 0)
            self.assertEqual(x.get_device(), 0)
            with torch.cuda.device(1):
                z = torch.randn(5, 5).cuda()
                self.assertEqual(z.get_device(), 1)
                q = x.add(y)
                self.assertEqual(q.get_device(), 0)
                w = torch.randn(5, 5).cuda()
                self.assertEqual(w.get_device(), 1)
            z = z.cuda()
            self.assertEqual(z.get_device(), 0)

    @unittest.skipIf(torch.cuda.device_count() < 2, "only one GPU detected")
    def test_copy_device(self):
        x = torch.randn(5, 5).cuda()
        with torch.cuda.device(1):
            y = x.cuda()
            self.assertEqual(y.get_device(), 1)
            self.assertIs(y.cuda(), y)
            z = y.cuda(0)
            self.assertEqual(z.get_device(), 0)
            self.assertIs(z.cuda(0), z)

        x = torch.randn(5, 5)
        with torch.cuda.device(1):
            y = x.cuda()
            self.assertEqual(y.get_device(), 1)
            self.assertIs(y.cuda(), y)
            z = y.cuda(0)
            self.assertEqual(z.get_device(), 0)
            self.assertIs(z.cuda(0), z)

    def test_serialization(self):
        x = torch.randn(5, 5).cuda()
        y = torch.IntTensor(2, 5).fill_(0).cuda()
        q = [x, y, x, y.storage()]
        with tempfile.NamedTemporaryFile() as f:
            torch.save(q, f)
            f.seek(0)
            q_copy = torch.load(f)
        self.assertEqual(q_copy, q, 0)
        q_copy[0].fill_(5)
        self.assertEqual(q_copy[0], q_copy[2], 0)
        self.assertTrue(isinstance(q_copy[0], torch.cuda.DoubleTensor))
        self.assertTrue(isinstance(q_copy[1], torch.cuda.IntTensor))
        self.assertTrue(isinstance(q_copy[2], torch.cuda.DoubleTensor))
        self.assertTrue(isinstance(q_copy[3], torch.cuda.IntStorage))
        q_copy[1].fill_(10)
        self.assertTrue(q_copy[3], torch.cuda.IntStorage(10).fill_(10))

    def test_type_conversions(self):
        x = torch.randn(5, 5)
        self.assertIs(type(x.float()), torch.FloatTensor)
        self.assertIs(type(x.cuda()), torch.cuda.DoubleTensor)
        self.assertIs(type(x.cuda().float()), torch.cuda.FloatTensor)
        self.assertIs(type(x.cuda().float().cpu()), torch.FloatTensor)
        self.assertIs(type(x.cuda().float().cpu().int()), torch.IntTensor)

        y = x.storage()
        self.assertIs(type(y.float()), torch.FloatStorage)
        self.assertIs(type(y.cuda()), torch.cuda.DoubleStorage)
        self.assertIs(type(y.cuda().float()), torch.cuda.FloatStorage)
        self.assertIs(type(y.cuda().float().cpu()), torch.FloatStorage)
        self.assertIs(type(y.cuda().float().cpu().int()), torch.IntStorage)

    @unittest.skipIf(torch.cuda.device_count() < 2, "only one GPU detected")
    def test_type_conversions_same_gpu(self):
        x = torch.randn(5, 5).cuda(1)
        self.assertEqual(x.int().get_device(), 1)

    def _test_broadcast(self, input):
        if torch.cuda.device_count() < 2:
            raise unittest.SkipTest("only one GPU detected")
        result = comm.broadcast(input, (0, 1))
        for i, t in enumerate(result):
            self.assertEqual(t.get_device(), i)
            self.assertEqual(t, input)

    def test_broadcast_cpu(self):
        self._test_broadcast(torch.randn(5, 5))

    def test_broadcast_gpu(self):
        self._test_broadcast(torch.randn(5, 5))

    @unittest.skipIf(torch.cuda.device_count() < 2, "only one GPU detected")
    def test_reduce_add(self):
        x = torch.randn(5, 5)
        y = torch.randn(5, 5)
        x_cuda = x.cuda(0)
        y_cuda = y.cuda(1)
        result = comm.reduce_add((x_cuda, y_cuda))
        self.assertEqual(result.get_device(), 0)
        self.assertEqual(result.cpu(), x + y)

    def _test_scatter(self, input, chunk_sizes=None, dim=0):
        if torch.cuda.device_count() < 2:
            raise unittest.SkipTest("only one GPU detected")
        result = comm.scatter(input, (0, 1), chunk_sizes, dim)
        self.assertEqual(len(result), 2)
        if chunk_sizes is None:
            chunk_sizes = tuple(repeat(input.size(dim) // 2, 2))
        chunk_start = 0
        for i, r in enumerate(result):
            chunk_end = chunk_start + chunk_sizes[i]
            index = [slice(None, None), slice(None, None)]
            index[dim] = slice(chunk_start, chunk_end)
            self.assertEqual(r, input[tuple(index)], 0)
            chunk_start = chunk_end

    def test_scatter_cpu(self):
        self._test_scatter(torch.randn(4, 4), dim=0)

    def test_scatter_cpu_dim(self):
        self._test_scatter(torch.randn(4, 4), dim=1)

    def test_scatter_cpu_sizes(self):
        self._test_scatter(torch.randn(6, 4), chunk_sizes=(2, 4))

    def test_scatter_gpu(self):
        self._test_scatter(torch.randn(4, 4).cuda(), dim=0)

    def test_scatter_gpu_dim(self):
        self._test_scatter(torch.randn(4, 4).cuda(), dim=1)

    def test_scatter_gpu_sizes(self):
        self._test_scatter(torch.randn(6, 4).cuda(), chunk_sizes=(2, 4))

    def _test_gather(self, dim):
        if torch.cuda.device_count() < 2:
            raise unittest.SkipTest("only one GPU detected")
        x = torch.randn(2, 5).cuda(0)
        y = torch.randn(2, 5).cuda(1)
        result = comm.gather((x, y), dim)

        expected_size = list(x.size())
        expected_size[dim] += y.size(dim)
        expected_size = torch.Size(expected_size)
        self.assertEqual(result.get_device(), 0)
        self.assertEqual(result.size(), expected_size)

        index = [slice(None, None), slice(None, None)]
        index[dim] = slice(0, x.size(dim))
        self.assertEqual(result[tuple(index)], x)
        index[dim] = slice(x.size(dim), x.size(dim) + y.size(dim))
        self.assertEqual(result[tuple(index)], y)

    def test_gather(self):
        self._test_gather(0)

    def test_gather_dim(self):
        self._test_gather(1)

    def test_from_sequence(self):
        seq = [list(range(i * 4, i * 4 + 4)) for i in range(5)]
        reference = torch.range(0, 19).resize_(5, 4)
        for t in types:
            cuda_type = get_gpu_type(t)
            self.assertEqual(cuda_type(seq), reference)

    def test_manual_seed(self):
        with freeze_rng_state():
            x = torch.zeros(4, 4).float().cuda()
            torch.cuda.manual_seed(2)
            self.assertEqual(torch.cuda.initial_seed(), 2)
            x.uniform_()
            torch.cuda.manual_seed(2)
            y = x.clone().uniform_()
            self.assertEqual(x, y)
            self.assertEqual(torch.cuda.initial_seed(), 2)

    def test_serialization(self):
        x = torch.randn(4, 4).cuda()
        with tempfile.NamedTemporaryFile() as f:
            torch.save(x, f)
            f.seek(0)
            x_copy = torch.load(f)
        self.assertEqual(x_copy, x)
        self.assertIs(type(x_copy), type(x))
        self.assertEqual(x_copy.get_device(), x.get_device())

    def test_serialization_empty(self):
        x = [torch.randn(4, 4).cuda(), torch.cuda.FloatTensor()]
        with tempfile.NamedTemporaryFile() as f:
            torch.save(x, f)
            f.seek(0)
            x_copy = torch.load(f)
        for original, copy in zip(x, x_copy):
            self.assertEqual(copy, original)
            self.assertIs(type(copy), type(original))
            self.assertEqual(copy.get_device(), original.get_device())

    @unittest.skipIf(torch.cuda.device_count() < 2, "detected only one GPU")
    def test_multigpu_serialization(self):
        x = [torch.randn(4, 4).cuda(0), torch.randn(4, 4).cuda(1)]
        with tempfile.NamedTemporaryFile() as f:
            torch.save(x, f)
            f.seek(0)
            x_copy = torch.load(f)
        for original, copy in zip(x, x_copy):
            self.assertEqual(copy, original)
            self.assertIs(type(copy), type(original))
            self.assertEqual(copy.get_device(), original.get_device())

    @unittest.skipIf(torch.cuda.device_count() < 2, "detected only one GPU")
    def test_multigpu_serialization_remap(self):
        x = [torch.randn(4, 4).cuda(0), torch.randn(4, 4).cuda(1)]

        def gpu_remap(storage, location):
            if location == 'cuda:1':
                return storage.cuda(0)

        with tempfile.NamedTemporaryFile() as f:
            torch.save(x, f)
            f.seek(0)
            x_copy = torch.load(f, map_location=gpu_remap)

        for original, copy in zip(x, x_copy):
            self.assertEqual(copy, original)
            self.assertIs(type(copy), type(original))
            self.assertEqual(copy.get_device(), 0)

    @unittest.skipIf(torch.cuda.device_count() < 2, "detected only one GPU")
    def test_multigpu_serialization_remap_dict(self):
        x = [torch.randn(4, 4).cuda(0), torch.randn(4, 4).cuda(1)]
        with tempfile.NamedTemporaryFile() as f:
            torch.save(x, f)
            f.seek(0)
            x_copy = torch.load(f, map_location={'cuda:1': 'cuda:0'})
        for original, copy in zip(x, x_copy):
            self.assertEqual(copy, original)
            self.assertIs(type(copy), type(original))
            self.assertEqual(copy.get_device(), 0)

    @unittest.skipIf(torch.cuda.device_count() < 2, "detected only one GPU")
    def test_cuda_set_device(self):
        x = torch.randn(5, 5)
        with torch.cuda.device(1):
            self.assertEqual(x.cuda().get_device(), 1)
            torch.cuda.set_device(0)
            self.assertEqual(x.cuda().get_device(), 0)
            with torch.cuda.device(1):
                self.assertEqual(x.cuda().get_device(), 1)
            self.assertEqual(x.cuda().get_device(), 0)
            torch.cuda.set_device(1)
        self.assertEqual(x.cuda().get_device(), 0)

    def test_is_tensor(self):
        for t in types:
            tensor = get_gpu_type(t)()
            self.assertTrue(torch.is_tensor(tensor))
        self.assertTrue(torch.is_tensor(torch.cuda.HalfTensor()))

    def test_cuda_synchronize(self):
        torch.cuda.synchronize()

    def test_streams(self):
        default_stream = torch.cuda.current_stream()
        user_stream = torch.cuda.Stream()
        self.assertEqual(torch.cuda.current_stream(), default_stream)
        self.assertNotEqual(default_stream, user_stream)
        self.assertEqual(default_stream.cuda_stream, 0)
        self.assertNotEqual(user_stream.cuda_stream, 0)
        with torch.cuda.stream(user_stream):
            self.assertEqual(torch.cuda.current_stream(), user_stream)
        self.assertTrue(user_stream.query())
        # copy 10 MB tensor from CPU-GPU which should take some time
        tensor1 = torch.ByteTensor(10000000).pin_memory()
        tensor2 = tensor1.cuda(async=True)
        self.assertFalse(default_stream.query())
        default_stream.synchronize()
        self.assertTrue(default_stream.query())

    @unittest.skipIf(torch.cuda.device_count() < 2, "detected only one GPU")
    def test_streams_multi_gpu(self):
        default_stream = torch.cuda.current_stream()
        self.assertEqual(default_stream.device, 0)
        stream = torch.cuda.Stream(device=1)
        self.assertEqual(stream.device, 1)
        with torch.cuda.device(1):
            self.assertEqual(torch.cuda.current_stream().device, 1)
            self.assertNotEqual(torch.cuda.current_stream(), default_stream)

    @unittest.skipIf(torch.cuda.device_count() < 2, "multi-GPU not supported")
    def test_tensor_device(self):
        self.assertEqual(torch.cuda.FloatTensor(1).get_device(), 0)
        self.assertEqual(torch.cuda.FloatTensor(1, device=1).get_device(), 1)
        with torch.cuda.device(1):
            self.assertEqual(torch.cuda.FloatTensor(1).get_device(), 1)
            self.assertEqual(torch.cuda.FloatTensor(1, device=0).get_device(), 0)
            self.assertEqual(torch.cuda.FloatTensor(1, device=None).get_device(), 1)

    def test_events(self):
        stream = torch.cuda.current_stream()
        event = torch.cuda.Event(enable_timing=True)
        self.assertTrue(event.query())
        start_event = torch.cuda.Event(enable_timing=True)
        stream.record_event(start_event)
        torch.cuda._sleep(int(50 * get_cycles_per_ms()))
        stream.record_event(event)
        self.assertFalse(event.query())
        event.synchronize()
        self.assertTrue(event.query())
        self.assertGreater(start_event.elapsed_time(event), 0)

    def test_caching_pinned_memory(self):
        cycles_per_ms = get_cycles_per_ms()

        # check that allocations are re-used after deletion
        t = torch.FloatTensor([1]).pin_memory()
        ptr = t.data_ptr()
        del t
        t = torch.FloatTensor([1]).pin_memory()
        self.assertEqual(t.data_ptr(), ptr, 'allocation not reused')

        # check that the allocation is not re-used if it's in-use by a copy
        gpu_tensor = torch.cuda.FloatTensor([0])
        torch.cuda._sleep(int(50 * cycles_per_ms))  # delay the copy
        gpu_tensor.copy_(t, async=True)
        del t
        t = torch.FloatTensor([1]).pin_memory()
        self.assertNotEqual(t.data_ptr(), ptr, 'allocation re-used too soon')
        self.assertEqual(list(gpu_tensor), [1])


for decl in tests:
    for t in types:
        tensor = t()
        gpu_tensor = get_gpu_type(t)()
        if len(decl) == 3:
            name, constr, arg_constr = decl
            desc = ''
        elif len(decl) == 4:
            name, constr, arg_constr, desc = decl
        elif len(decl) == 5:
            name, constr, arg_constr, desc, type_subset = decl
            if t not in type_subset:
                continue

        precision = custom_precision.get(name, TestCuda.precision)
        for inplace in (True, False):
            if inplace:
                name_inner = name + '_'
            else:
                name_inner = name
            if not hasattr(tensor, name_inner):
                continue
            if not hasattr(gpu_tensor, name_inner):
                print("Ignoring {}, because it's not implemented by torch.cuda.{}".format(
                    name_inner, gpu_tensor.__class__.__name__))
                continue

            test_name = 'test_' + t.__name__ + '_' + name_inner
            if desc:
                test_name += '_' + desc

            assert not hasattr(TestCuda, test_name), "Duplicated test name: " + test_name
            setattr(TestCuda, test_name, compare_cpu_gpu(constr, arg_constr, name_inner, t, precision))

if __name__ == '__main__':
    run_tests()
