pytorch/torch/distributed/_pycute/int_tuple.py
fduwjj 232dd65c15 [CuTe] Change the logic of pycute manipulation ops like coalesce, complement from co-lex to lex (#162690)
PyTorch tensor iteration (.view, contiguous, broadcasting) and NumPy array indexing all follow lexicographic (row-major) order. In Lexicographic (lex) on (i0, i1, …, i{k-1}): the leftmost index(stride is larger) changes fastest and the rightmost index changes slowest and usually last dim is contiguous.

However original pycute is all based on co-lex, after porting their code into pytorch and some cosmetic change, we now make it lex so that we can use it for use cases like device mesh internal bookkeeping and other stuff as well.

Changes included in this PR:
1. We changes all API ported in, included prefix_product(stride inferring and rename it to suffix_product), idx2crd, crd2idx, coalesce, composition, complement, right_inverse and left_inverse to make sure they are working in the lex way.
2. Added more unit test cases for some API mentioned above since existing unit tests do not have full coverage.
3. One bug fix inside composition, which will lead to infinite recursive call.

Pull Request resolved: https://github.com/pytorch/pytorch/pull/162690
Approved by: https://github.com/ezyang
ghstack dependencies: #162413, #162534, #162414
2025-09-16 19:53:45 +00:00

256 lines
9.2 KiB
Python

#################################################################################################
#
# Copyright (c) 2023 - 2025 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
# SPDX-License-Identifier: BSD-3-Clause
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
# 1. Redistributions of source code must retain the above copyright notice, this
# list of conditions and the following disclaimer.
#
# 2. Redistributions in binary form must reproduce the above copyright notice,
# this list of conditions and the following disclaimer in the documentation
# and/or other materials provided with the distribution.
#
# 3. Neither the name of the copyright holder nor the names of its
# contributors may be used to endorse or promote products derived from
# this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#
#################################################################################################
"""
Functions for manipulating IntTuples
"""
from functools import reduce
from itertools import chain
from typing import Optional, Union
from typing_extensions import TypeAlias, TypeIs
from .typing import Integer
# Type aliases for better readability
IntTuple: TypeAlias = Union[int, tuple["IntTuple", ...]]
def is_int(x: object) -> TypeIs[int]:
return isinstance(x, Integer)
def is_tuple(x: object) -> TypeIs[tuple]:
return isinstance(x, tuple)
def flatten(t: IntTuple) -> tuple[int, ...]:
if is_tuple(t):
if len(t) == 0:
return ()
else:
return tuple(i for a in t for i in flatten(a))
else:
return (t,)
def signum(a: int) -> int:
return bool(a > 0) - bool(a < 0)
def product(a: IntTuple) -> int:
if is_tuple(a):
return reduce(lambda val, elem: val * product(elem), a, 1)
else:
return a
def inner_product(a: IntTuple, b: IntTuple) -> int:
if is_tuple(a) and is_tuple(b): # tuple tuple
assert len(a) == len(b)
return sum(inner_product(x, y) for x, y in zip(a, b))
else: # "int" "int"
assert not is_tuple(a) and not is_tuple(b)
return a * b
def tuple_max(a: IntTuple) -> int:
if is_tuple(a):
return max(tuple_max(x) for x in a)
else:
return a
def elem_scale(a: IntTuple, b: IntTuple) -> IntTuple:
if is_tuple(a):
if is_tuple(b): # tuple tuple
assert len(a) == len(b)
return tuple(elem_scale(x, y) for x, y in zip(a, b))
else: # tuple "int"
raise AssertionError("Invalid combination: tuple with int")
else:
if is_tuple(b): # "int" tuple
return elem_scale(a, product(b))
else: # "int" "int"
return a * b
# Inclusive prefix ceil div with output congruent to input a
def shape_div(a: IntTuple, b: IntTuple) -> IntTuple:
if is_tuple(a):
if is_tuple(b): # tuple tuple
assert len(a) == len(b)
return tuple(shape_div(x, y) for x, y in zip(a, b))
else: # tuple "int"
# r = [shape_div(a[0],b)] + [shape_div(a[i],b := shape_div(b, product(a[i-1]))) for i in range(1,len(a))]
r = []
for v in a:
r.append(shape_div(v, b))
b = shape_div(b, product(v))
return tuple(r)
else:
if is_tuple(b): # "int" tuple
return shape_div(a, product(b))
else: # "int" "int"
assert a % b == 0 or b % a == 0
return (a + b - 1) // b
# Exclusive suffix product with output congruent to input a (lexicographic)
def suffix_product(a: IntTuple, init: IntTuple = 1) -> IntTuple:
# TODO: With all these length asserts, may want to create a zip_strict wrapper.
if is_tuple(a):
if is_tuple(init): # tuple tuple
assert len(a) == len(init)
return tuple(suffix_product(x, i) for x, i in zip(a, init))
else: # tuple "int"
# Process from right to left for lexicographic ordering
# r = [prefix_product(a[len(a)-1],init)] +
# [prefix_product(a[i],init := init * product(a[i+1])) for i in range(len(a)-1,0)].reverse()
r = []
# Calculate products from right to left, appending to list
for i in range(len(a) - 1, -1, -1):
r.append(suffix_product(a[i], init))
init = init * product(a[i])
# Reverse to get correct lexicographic order
r.reverse()
return tuple(r)
else:
if is_tuple(init): # "int" tuple
raise AssertionError("Invalid combination: int with tuple init")
else: # "int" "int"
return init
def idx2crd(
idx: IntTuple, shape: IntTuple, stride: Optional[IntTuple] = None
) -> IntTuple:
if stride is None:
stride = suffix_product(shape)
if is_tuple(idx):
if is_tuple(shape) and is_tuple(stride): # tuple tuple tuple
assert len(idx) == len(shape) and len(stride) == len(shape)
return tuple(idx2crd(i, s, d) for i, s, d in zip(idx, shape, stride))
else: # tuple "int" "int"
raise AssertionError("Invalid combination: tuple with int stride")
else:
if is_tuple(shape) and is_tuple(stride): # "int" tuple tuple
assert len(shape) == len(stride)
return tuple(idx2crd(idx, s, d) for s, d in zip(shape, stride))
else: # "int" "int" "int"
assert not is_tuple(shape) and not is_tuple(stride)
return (idx // stride) % shape # all are ints after type checks
def crd2idx(
crd: Optional[IntTuple], shape: IntTuple, stride: Optional[IntTuple] = None
) -> int:
if stride is None:
stride = suffix_product(shape)
if is_tuple(crd):
if is_tuple(shape) and is_tuple(stride): # tuple tuple tuple
assert len(crd) == len(shape) and len(stride) == len(shape)
return sum(crd2idx(c, s, d) for c, s, d in zip(crd, shape, stride))
else: # tuple "int" "int"
raise AssertionError(f"Invalid combination: crd={crd}, shape={shape}")
else:
if crd is None:
crd = 0
if is_tuple(shape) and is_tuple(stride): # "int" tuple tuple
assert len(shape) == len(stride)
result = 0
# Process from right to left for lexicographic ordering
for i in range(len(shape) - 1, 0, -1):
result += crd2idx(crd % product(shape[i]), shape[i], stride[i])
crd = crd // product(shape[i])
return result + crd2idx(crd, shape[0], stride[0])
else: # "int" "int" "int"
assert not is_tuple(shape) and not is_tuple(stride)
return crd * stride # all are ints after type checks
# Transform crd into the dst_shape's iteration space
def crd2crd(
crd: IntTuple, dst_shape: IntTuple, src_shape: Optional[IntTuple] = None
) -> IntTuple:
if is_tuple(crd):
if is_tuple(dst_shape): # tuple tuple
assert len(crd) == len(dst_shape)
return tuple(crd2crd(x, y) for x, y in zip(crd, dst_shape))
else: # tuple "int"
# Ambiguous unless we have src_shape
assert src_shape is not None
return crd2idx(crd, src_shape)
else:
if is_tuple(dst_shape): # "int" tuple
return idx2crd(crd, dst_shape)
else: # "int" "int"
assert crd < dst_shape
return crd
# Filter trg according to crd: keep only elements of trg that are paired with None
def slice_(crd: Union[None, tuple, int], trg: Union[tuple, int]) -> Union[tuple, int]:
if is_tuple(crd):
if is_tuple(trg): # tuple tuple
assert len(crd) == len(trg)
# match C++ behavior of `filter_tuple` using `tuple_cat(...)`
return tuple(
chain(
*filter( # type: ignore[arg-type] # filter returns Iterator which is compatible
lambda x: x != (),
[slice_(c, s) for c, s in zip(crd, trg)],
)
)
)
else:
raise AssertionError("Invalid combination: tuple crd with int trg")
elif crd is None:
# match C++ behavior `return cute::tuple<B>{b};`
return (trg,)
else:
return ()
# Determine if None appears at any of an int_tuples' terminals
def has_none(a: Union[None, tuple, int]) -> bool:
if is_tuple(a):
return any(has_none(v) for v in a)
else:
return a is None