Source code for pacman.operations.router_compressors.ordered_covering_router_compressor.utils
# Copyright (c) 2017 The University of Manchester
#
# 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
#
# https://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.
"""
based on
https://github.com/project-rig/rig/blob/master/rig/routing_table/utils.py
"""
[docs]def intersect(key_a, mask_a, key_b, mask_b):
"""
Return if key-mask pairs intersect (i.e., would both match some of the
same keys).
For example, the key-mask pairs ``00XX`` and ``001X`` both match the keys
``0010`` and ``0011`` (i.e., they do intersect)::
>>> intersect(0b0000, 0b1100, 0b0010, 0b1110)
True
But the key-mask pairs ``00XX`` and ``11XX`` do not match any of the same
keys (i.e., they do not intersect)::
>>> intersect(0b0000, 0b1100, 0b1100, 0b1100)
False
:param int key_a:
:param int mask_a: The first key-mask pair
:param int key_b:
:param int mask_b: The second key-mask pair
:rtype: bool
:return: True if the two key-mask pairs intersect, otherwise False.
"""
return (key_a & mask_b) == (key_b & mask_a)