pytorch/test/test_jit_cuda_fuser.py
Christian Sarofeen f11c4f90c2 New CUDA Fuser: Unrolling support, interface refactor (#36435)
Summary:
Unrolling support has been added in a way that we get good performing code on GPUs. Not sure how long this link will last but an example of a generated unrolled kernel is:
https://godbolt.org/z/i0uAv3

What can be seen from there is multiple calls of "ld.global.f32" without "ld.store.f32" in between them (and vice versa). This means that we are launching multiple loads that can be run in parallel, as well as multiple stores that can be run in parallel. This can be a crucial optimization for memory bound kernels. This was generally a point of concern in TVM as an attempt of a similar kernel from TVM produces: https://godbolt.org/z/Vu97vG which surrounds load - store pairs in conditional branches preventing the benefits of unrolling.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/36435

Reviewed By: ZolotukhinM

Differential Revision: D21024011

Pulled By: soumith

fbshipit-source-id: e852e282fa7a304aba962e1926f756098c011fe0
2020-04-16 09:20:24 -07:00

143 lines
5.2 KiB
Python

from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
from __future__ import unicode_literals
import unittest
import torch
from torch.testing._internal.common_utils import run_tests, ProfilingMode, GRAPH_EXECUTOR, skipIfRocm
from test_jit import JitTestCase, RUN_CUDA
if GRAPH_EXECUTOR == ProfilingMode.PROFILING:
torch._C._jit_set_profiling_executor(True)
torch._C._jit_set_profiling_mode(True)
class TestCudaFuser(JitTestCase):
def setUp(self):
super(TestCudaFuser, self).setUp()
self.old_cpu_fuse = torch._C._jit_can_fuse_on_cpu()
self.old_gpu_fuse = torch._C._jit_can_fuse_on_gpu()
torch._C._jit_override_can_fuse_on_cpu(False)
torch._C._jit_override_can_fuse_on_gpu(False)
if(RUN_CUDA):
torch._C._jit_register_cuda_fuser()
def tearDown(self):
if(RUN_CUDA):
torch._C._jit_clear_cuda_fuser()
torch._C._jit_override_can_fuse_on_cpu(self.old_cpu_fuse)
torch._C._jit_override_can_fuse_on_gpu(self.old_gpu_fuse)
super(TestCudaFuser, self).tearDown()
def _has_cuda_fusion_group(self, graph):
has_cuda_fusion_group = False
for n in graph.nodes():
if n.kind() == 'prim::CudaFusionGroup':
has_cuda_fusion_group = True
return has_cuda_fusion_group
@unittest.skipIf(not RUN_CUDA, "requires CUDA")
@unittest.skipIf(GRAPH_EXECUTOR != ProfilingMode.PROFILING, "Requires profiling node to run cuda fuser")
@skipIfRocm
def test_const(self):
def t(x, y):
o = x + y
o = o + 2.0
return o
t_jit = torch.jit.script(t)
x = torch.randn(4, 8, dtype=torch.float, device="cuda")
y = torch.randn(4, 8, dtype=torch.float, device="cuda")
jit_o = t_jit(x, y)
jit_o = t_jit(x, y)
o = t(x, y)
self.assertEqual(o, jit_o)
self.assertTrue(self._has_cuda_fusion_group(t_jit.graph_for(x, y)))
@unittest.skipIf(not RUN_CUDA, "requires CUDA")
@unittest.skipIf(GRAPH_EXECUTOR != ProfilingMode.PROFILING, "Requires profiling node to run cuda fuser")
@skipIfRocm
def test_chunk(self):
def t(x, y, z, q):
o = x + q
x0, x1 = torch.chunk(o, 2)
o = x0 + x1
o = o + y
o = o * z
o = torch.relu(o)
return o
t_jit = torch.jit.script(t)
x = torch.randn(4, 8, dtype=torch.float, device="cuda")
y = torch.randn(2, 8, dtype=torch.float, device="cuda")
z = torch.randn(2, 8, dtype=torch.float, device="cuda")
q = torch.randn(4, 8, dtype=torch.float, device="cuda")
jit_o = t_jit(x, y, z, q)
jit_o = t_jit(x, y, z, q)
o = t(x, y, z, q)
self.assertEqual(o, jit_o)
self.assertTrue(self._has_cuda_fusion_group(t_jit.graph_for(x, y, z, q)))
@unittest.skipIf(not RUN_CUDA, "requires CUDA")
@unittest.skipIf(GRAPH_EXECUTOR != ProfilingMode.PROFILING, "Requires profiling node to run cuda fuser")
@skipIfRocm
def test_scalar_input(self):
def t(x : torch.Tensor, y : torch.Tensor, z : float):
o = x + y
o = o + z
return o
t_jit = torch.jit.script(t)
x = torch.randn(4, 8, 32, 32, dtype=torch.float, device="cuda")
y = torch.randn(4, 8, 1, 32, dtype=torch.float, device="cuda")
y = y.expand(4, 8, 32, 32)
jit_o = t_jit(x, y, 2.0)
jit_o = t_jit(x, y, 2.0)
o = t(x, y, 2.0)
self.assertEqual(o, jit_o)
self.assertTrue(self._has_cuda_fusion_group(t_jit.graph_for(x, y, 2.0)))
@unittest.skipIf(not RUN_CUDA, "requires CUDA")
@unittest.skipIf(GRAPH_EXECUTOR != ProfilingMode.PROFILING, "Requires profiling node to run cuda fuser")
@skipIfRocm
def test_broadcasting(self):
def t(x : torch.Tensor, y : torch.Tensor, z : float):
o = x + y
o = o + z
return o
t_jit = torch.jit.script(t)
x = torch.randn(4, 8, 32, 32, dtype=torch.float, device="cuda")
y = torch.randn(32, 32, dtype=torch.float, device="cuda")
jit_o = t_jit(x, y, 2.0)
jit_o = t_jit(x, y, 2.0)
o = t(x, y, 2.0)
self.assertEqual(o, jit_o)
self.assertTrue(self._has_cuda_fusion_group(t_jit.graph_for(x, y, 2.0)))
@unittest.skipIf(not RUN_CUDA, "requires CUDA")
@unittest.skipIf(GRAPH_EXECUTOR != ProfilingMode.PROFILING, "Requires profiling node to run cuda fuser")
@skipIfRocm
def test_broadcasting_multiple_output_shape(self):
def t(x : torch.Tensor, y : torch.Tensor, z : torch.Tensor):
o = x + 12
o1 = o + y
o2 = o + z
oo = o1.sum() + o2.sum()
return oo
t_jit = torch.jit.script(t)
x = torch.randn(32, 32, dtype=torch.float, device="cuda")
y = torch.randn(2, 32, 32, dtype=torch.float, device="cuda")
z = torch.randn(4, 32, 32, dtype=torch.float, device="cuda")
jit_o = t_jit(x, y, z)
jit_o = t_jit(x, y, z)
o = t(x, y, z)
self.assertEqual(o, jit_o)
# Currently cannot fuse this
self.assertFalse(self._has_cuda_fusion_group(t_jit.graph_for(x, y, z)))
if __name__ == '__main__':
run_tests()