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#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#
from aitemplate import backend
from aitemplate.backend import registry
from aitemplate.compiler.base import Operator, Tensor
from aitemplate.compiler.dtype import normalize_dtype
[docs]class cast(Operator):
"""
Returns the cast of input tensor to specified type.
Only the conversion between any pair of float16, bfloat16,
and float32 dtypes is supported.
Args:
x (Tensor): the source tensor
dtype (str): the target type for the cast operator
Returns:
Tensor: a tensor with the type converted to the
specified dtype.
"""
def __init__(self) -> None:
super().__init__()
self._attrs["op"] = "cast"
self._attrs["has_profiler"] = False
def __call__(
self,
x: Tensor,
dtype: str = "bfloat16",
) -> Tensor:
x_dtype = normalize_dtype(x._attrs["dtype"])
dtype = normalize_dtype(dtype)
if x_dtype not in ("float16", "bfloat16", "float32", "bool"):
raise TypeError(
f"Expected dtype for x must be float16,bfloat16 or float32 , but got {x_dtype}."
)
if dtype not in ("float16", "bfloat16", "float32"):
raise TypeError(
f"Expected dtype to cast must be float16,bfloat16 or float32 , but got {dtype}."
)
if dtype == x_dtype:
return x
self._attrs["inputs"] = [x]
self._attrs["cast_dtype"] = dtype
self._set_depth()
output_shape = x._attrs["shape"]
output = Tensor(
output_shape,
src_ops={self},
dtype=dtype,
)
self._attrs["outputs"] = [output]
return output
[docs] def gen_function(self) -> str:
target = backend.target.Target.current()
func_key = f"{target.name()}.{self._attrs['op']}.gen_function"
func = registry.get(func_key)
return func(self._attrs)