创建 TVM 的 NDArray 的子类

tvm_ext.ivec_create

import tvm
from tvm_book.tvm_ext.libinfo import _load_lib

_LIB, _LIB_NAME = _load_lib(name="libtvm_ext.so", search_path=["outputs/libs"])
tvm._ffi._init_api("tvm_ext", __name__)

要使用此插件，外部库应执行以下操作：

1. 继承 TVM 的 NDArray 和 NDArray 容器；

2. 遵循新的对象协议以将新 NDArray 定义为引用类。

3. 在 Python 前端上，继承 tvm.nd.NDArray，并使用 tvm.register_object 注册类型。

@tvm.register_object("tvm_ext.IntVector")
class IntVec(tvm.Object):
    """Example for using extension class in c++"""

    @property
    def _tvm_handle(self):
        return self.handle.value

    def __getitem__(self, idx):
        return ivec_get(self, idx)

ivec = ivec_create(1, 2, 3)
assert isinstance(ivec, IntVec)
assert ivec[0] == 1
assert ivec[1] == 2

def ivec_cb(v2):
    assert isinstance(v2, IntVec)
    assert v2[2] == 3

tvm.runtime.convert(ivec_cb)(ivec)

tvm_ext.NDSubClass

@tvm.register_object("tvm_ext.NDSubClass")
class NDSubClass(tvm.nd.NDArrayBase):
    """Example for subclassing TVM's NDArray infrastructure.

    By inheriting TVM's NDArray, external libraries could
    leverage TVM's FFI without any modification.
    """

    @staticmethod
    def create(additional_info):
        return nd_create(additional_info)

    @property
    def additional_info(self):
        return nd_get_additional_info(self)

    def __add__(self, other):
        return nd_add_two(self, other)

a = NDSubClass.create(additional_info=3)
b = NDSubClass.create(additional_info=5)
assert isinstance(a, NDSubClass)
c = a + b
d = a + a
e = b + b
assert a.additional_info == 3
assert b.additional_info == 5
assert c.additional_info == 8
assert d.additional_info == 6
assert e.additional_info == 10