Do you have an example under windows?

[yeyuxmf]

The custom layer uses JIT mechanism to invoke on the c++ side, which seems to require registration in scripts, such as:
.# include <torch/script.h>
Torch:: Tensor warp_perspective (torch:: Tensor image, torch:: Tensor warp){
Torch:: Tensor output = torch:: add (image, warp);
Return output. clone ();
}
Static auto registry=
Torch:: jit:: Register Operators ("my_ops:: warp_perspective", & warp_perspective);

This is the application under Ubuntu. Do you have an example under windows?I don't know how to run the example provided in extension-script under Windows.

[soumith]

cc: @peterjc123

[peterjc123]

Have you experienced any error when using this piece of code? The suggested way is to write a CMake script like this and then mkdir build && cmake .. and cmake --build ..

[yeyuxmf]

@peterjc123 Thank you very much for your answer. First, I tried this under the Windows platform. It can be compiled and passed. But the problem is that I want to use torch. jit. script mechanism to export the model, so that it can be easily deployed in c++ end.I couldn't successfully export the model.
The code is as follows：
import torch
import warp_perspective

@torch.jit.script
def compute(x, y):
x = torch.ops.my_ops.warp_perspective.forward(y, y)
return x.matmul(y)

print(compute.graph)
print(compute(torch.randn(8, 8), torch.randn(8, 8)))
compute.save("example.pt")

The implementation code of the custom warp_perspective function is as follows(warp_perspective .cpp):
#include <torch/script.h>
#include <torch/extension.h>
torch::Tensor warp_perspective_forward(torch::Tensor image, torch::Tensor warp) {
torch::Tensor output = torch::add(image, warp);
return output.clone();
}
static auto registry =
torch::jit::RegisterOperators("my_ops::warp_perspective", &warp_perspective_forward);
PYBIND11_MODULE(TORCH_EXTENSION_NAME, m) {
m.def("forward", &warp_perspective_forward, "WARP_PERSPECTIVE forward (CUDA)");
}

[peterjc123]

@huang229 So the issue is on the python side, right? What error does it throw?

[yeyuxmf]

@peterjc123 I think the problem is that the warp_perspective function has not been successfully registered in the JIT mechanism.Therefore, the JIT mechanism cannot be used to export the model on the python port.I don't know what to do.

[peterjc123]

If you remove x = torch.ops.my_ops.warp_perspective.forward(y, y), can you manage to export the model?

[yeyuxmf]

x= torch::add(y, y) The model can be successfully derived.

[peterjc123]

Okay, another question, will x = torch.ops.my_ops.warp_perspective.forward(y, y) work when not wrapped up with @torch.jit.script?

[yeyuxmf]

yes.This is a direct error report.
The error is as follows：
File "D:\python-3.7.3\lib\site-packages\torch\jit_init_.py", line 1077, in _compile_function
script_fn = torch._C._jit_script_compile(qualified_name, ast, _rcb, get_default_args(fn))

[yeyuxmf]

There is no save attribute without using the @torch.jit.script model.

[peterjc123]

I think there should be something wrong with the jit compiler code. It will be easier to deal with if you could post a full C++ stack trace.

[yeyuxmf]

@peterjc123 Successful compilation of scripts (warp_perspective.cpp).There are no errors displayed.I feel that the following code doesn't work under Windows.
static auto registry = torch::jit::RegisterOperators("my_ops::warp_perspective", &warp_perspective_forward);

The errors completed when exporting the model are as follows:
Connected to pydev debugger (build 191.6605.12)
Traceback (most recent call last):
File "D:\PyCharm Community Edition 2019.1.1\helpers\pydev\pydevd.py", line 1741, in
main()
File "D:\PyCharm Community Edition 2019.1.1\helpers\pydev\pydevd.py", line 1735, in main
globals = debugger.run(setup['file'], None, None, is_module)
File "D:\PyCharm Community Edition 2019.1.1\helpers\pydev\pydevd.py", line 1135, in run
pydev_imports.execfile(file, globals, locals) # execute the script
File "D:\PyCharm Community Edition 2019.1.1\helpers\pydev_pydev_imps_pydev_execfile.py", line 18, in execfile
exec(compile(contents+"\n", file, 'exec'), glob, loc)
File "D:/vs+opencv/tmp/script.py", line 4, in
@torch.jit.script
File "D:\python-3.7.3\lib\site-packages\torch\jit_init_.py", line 1181, in script
return _compile_function(fn=obj, qualified_name=qualified_name, _frames_up=_frames_up + 1, _rcb=rcb)
File "D:\python-3.7.3\lib\site-packages\torch\jit_init.py", line 1077, in _compile_function
script_fn = torch._C._jit_script_compile(qualified_name, ast, _rcb, get_default_args(fn))
RuntimeError:
attribute lookup is not defined on builtin:
at D:/vs+opencv/tmp/script.py:6:9
@torch.jit.script
def compute(x, y):
x = torch.ops.my_ops.warp_perspective.forward(y, y)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ <--- HERE
return x.matmul(y)

[peterjc123]

cc @ezyang Do you know what might be the reason? I'm not so familiar with the JIT things here.

[yeyuxmf]

Here's all my code:
It contains three scripts: setup.py, cpp, script.py.
cpp：
#include <torch/script.h>
#include <torch/extension.h>
torch::Tensor warp_perspective_forward(torch::Tensor image, torch::Tensor warp) {
torch::Tensor output = torch::add(image, warp);
return output.clone();
}
static auto registry =
torch::jit::RegisterOperators("my_ops::warp_perspective", &warp_perspective_forward);
PYBIND11_MODULE(TORCH_EXTENSION_NAME, m) {
m.def("forward", &warp_perspective_forward, "WARP_PERSPECTIVE forward (CUDA)");
}

setup.py：
from setuptools import setup
from torch.utils.cpp_extension import BuildExtension, CppExtension

setup(
name="warp_perspective",
ext_modules=[
CppExtension(
"warp_perspective",
["example_app/warp_perspective/op.cpp"],
)
],
cmdclass={"build_ext": BuildExtension},
)

script.py：
import torch
import warp_perspective

@torch.jit.script
def compute(x, y):
x = torch.ops.my_ops.warp_perspective.forward(y, y)
return x.matmul(y)

print(compute.graph)
print(compute(torch.randn(8, 8), torch.randn(8, 8)))
compute.save("example.pt")

[yeyuxmf]

@peterjc123 Thank you very much for taking the time to help me.
@ezyang Hello, I want to achieve this function under the Windows system.