DriverTrac/venv/lib/python3.12/site-packages/jax/_src/hijax.py
2025-11-28 09:08:33 +05:30

300 lines
9.0 KiB
Python

# Copyright 2025 The JAX Authors.
#
# 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.
from __future__ import annotations
from dataclasses import dataclass
import itertools as it
from typing import Any
from jax._src import core
from jax._src.effects import Effect
from jax._src.interpreters import ad
from jax._src.interpreters import partial_eval as pe
from jax._src import ad_util
from jax._src.util import safe_zip, safe_map
from jax._src.tree_util import tree_flatten, tree_unflatten, tree_leaves
map, unsafe_map = safe_map, map
zip, unsafe_zip = safe_zip, zip
PyTreeDef = Any
LoVal = Any
HiVal = Any
# Hijax extension API
LoType = core.AbstractValue
QDD = core.QuasiDynamicData
ShapedArray = core.ShapedArray
class HiPrimitive(core.Primitive):
def __init__(self, name):
self.name = name
ad.primitive_jvps[self] = self.jvp
ad.primitive_transposes[self] = self.transpose
pe.custom_staging_rules[self] = self.staging
def staging(self, trace, source_info, *args, **kwargs):
trace.frame.is_high = True
return trace.default_process_primitive(
self, args, kwargs, source_info=source_info)
def is_high(self, **params) -> bool:
return True
def is_effectful(self, params) -> bool: # type: ignore
return False # default immutable
# type checking and forward type propagation
def abstract_eval(self, *arg_avals, **params):
assert False, "must override"
# lowering implements the primitive in terms of lojax inputs/outputs/ops
def to_lojax(self, *lotypes_wrapped_in_hitypes, **params):
assert False, "must override"
# autodiff interface
def jvp(self, primals, tangents, **params):
assert False, "must override"
# transposition is only required if the primitive is linear in some inputs
def transpose(self, *args, **params):
assert False, "must override"
class HiType(core.AbstractValue):
has_qdd = False # immutable
# type equality
def __hash__(self): assert False, "must override"
def __eq__(self, other): assert False, "must override"
# lowering from hijax type to lojax types
def lo_ty(self) -> list[core.AbstractValue]:
assert False, "must override"
# define lowering from hijax value to lojax values and back (like pytrees)
def lower_val(self, hi_val: HiVal) -> list[LoVal]:
assert False, "must override"
def raise_val(self, *lo_vals: LoVal) -> HiVal:
assert False, "must override"
# autodiff interface
def to_tangent_aval(self) -> HiType:
assert False, "must override"
# the next two are required if this type is itself a tangent type
def vspace_zero(self) -> HiVal:
assert False, "must override"
def vspace_add(self, x: HiVal, y: HiVal) -> HiVal:
assert False, "must override"
class MutableHiType(core.AbstractValue):
has_qdd = True # mutable and potentially type-changing
type_state = core.aval_method(core.cur_qdd)
# type equality
def __hash__(self): assert False, "must override"
def __eq__(self, other): assert False, "must override"
# define lowering from (mutable) hijax type to (immutable) lojax types
def lo_ty_qdd(self, state: QDD) -> list[core.AbstractValue]:
assert False, "must override"
# define lowering from hijax value to lojax values and back, depending on qdd
def new_from_loval(self, state: QDD, *vals: LoVal) -> HiVal:
assert False, "must override"
def read_loval(self, state: QDD, val: HiVal) -> list[LoVal]:
assert False, "must override"
# define how to mutate/set the mutable hijax value given immutable lojax vals
def update_from_loval(self, state: QDD, val: HiVal, *lo_vals: LoVal) -> None:
assert False, "must override"
# autodiff interface
def to_tangent_aval(self) -> HiType:
assert False, "must override"
def register_hitype(val_cls, typeof_fn) -> None:
core.pytype_aval_mappings[val_cls] = typeof_fn
def hijax_method(f):
return core.aval_method(f)
# Boxes
## Box API
def new_box():
(), treedef = tree_flatten(None)
return new_box_p.bind(treedef=treedef)
def box_get(box):
tys = core.cur_qdd(box)
leaf_vals = box_get_p.bind(box, avals=tuple(tys.leaf_avals))
return tree_unflatten(tys.treedef, leaf_vals)
def box_set(box, val):
leaves, treedef = tree_flatten(val)
box_set_p.bind(box, *leaves, treedef=treedef)
## Box implementation
@dataclass(frozen=True)
class BoxTypeState(QDD):
leaf_avals: tuple[core.AbstractValue, ...]
treedef: PyTreeDef
def to_tangent_qdd(self):
leaf_avals = tuple(a.to_tangent_aval() for a in self.leaf_avals)
return BoxTypeState(leaf_avals, self.treedef)
def normalize(self):
leaf_types = tuple(a.normalize() for a in self.leaf_avals)
return BoxTypeState(leaf_types, self.treedef)
class BoxTy(MutableHiType):
has_qdd = True
# forwarded to value
get = core.aval_method(box_get)
set = core.aval_method(box_set)
# aval interface: hashability and str_short
def __hash__(self): return hash(BoxTy)
def __eq__(self, other): return isinstance(other, BoxTy)
def str_short(self, short_dtypes=False, **_) -> str: # type: ignore
return 'BoxTy'
# mutable interface
def lo_ty_qdd(self, box_state):
return [lo_ty for t in box_state.leaf_avals for lo_ty in t.lo_ty()]
def new_from_loval(self, box_state: BoxTypeState, *lo_vals) -> Box: # type: ignore
lo_vals_ = iter(lo_vals)
hi_vals = [hi_ty.raise_val(*it.islice(lo_vals_, len(hi_ty.lo_ty()))) # type: ignore
for hi_ty in box_state.leaf_avals]
assert next(lo_vals_, None) is None
return Box(tree_unflatten(box_state.treedef, hi_vals)) # will be mutated
def read_loval(self, box_state: BoxTypeState, box) -> list: # type: ignore
leaf_vals, treedef = tree_flatten(box_get(box))
assert treedef == box_state.treedef
return [lo_val for hi_ty, hi_val in zip(box_state.leaf_avals, leaf_vals)
for lo_val in hi_ty.lower_val(hi_val)] # type: ignore
def update_from_loval(self, box_state: BoxTypeState, box, *lo_vals) -> None: # type: ignore
lo_vals_ = iter(lo_vals)
hi_vals = [hi_ty.raise_val(*it.islice(lo_vals_, len(hi_ty.lo_ty()))) # type: ignore
for hi_ty in box_state.leaf_avals]
assert next(lo_vals_, None) is None
box_set(box, tree_unflatten(box_state.treedef, hi_vals))
def to_tangent_aval(self):
return BoxTy()
class Box: # noqa: F811
def __init__(self, val):
self._val = val
def get(self):
return box_get(self)
def set(self, val):
box_set(self, val)
def cur_qdd(self):
return self.type_state()
@property
def ty(self):
return BoxTy()
def type_state(self):
leaves, treedef = tree_flatten(self._val)
leaf_avals = tuple(map(core.typeof, leaves))
return BoxTypeState(leaf_avals, treedef)
register_hitype(Box, lambda b: b.ty)
box_effect = Effect()
class NewBox(HiPrimitive):
def is_high(self, *, treedef) -> bool: return True # type: ignore
def abstract_eval(self, *, treedef):
leaves, treedef = tree_flatten(None)
qdd = BoxTypeState(tuple(leaves), treedef)
return core.AvalQDD(BoxTy(), qdd), {box_effect}
def to_lojax(_, *, treedef):
return Box(None)
def jvp(_, primals, tangents, *, treedef):
assert False # TODO
def transpose(_, *args, treedef):
assert False # TODO
new_box_p = NewBox('new_box')
class BoxSet(HiPrimitive):
multiple_results = True
def is_high(self, *, treedef) -> bool: return True # type: ignore
def abstract_eval(self, box_ty, *leaf_avals, treedef):
box_ty.mutable_qdd.update(BoxTypeState(leaf_avals, treedef))
return [], {box_effect} # TODO better typechecking...
def to_lojax(_, box, *leaves, treedef):
box._val = tree_unflatten(treedef, leaves)
return []
def jvp(_, primals, tangents, *, treedef):
box, *vals = primals
box_dot, *val_dots = tangents
if type(box_dot) is ad_util.Zero:
raise Exception("can't differentiate Box.set operation, "
"did you forget jax.lax.stop_gradient?")
box_set_p.bind(box, *vals, treedef=treedef)
box_set_p.bind(box_dot, *val_dots, treedef=treedef)
return [], []
def transpose(_, *args, treedef):
assert False # TODO
box_set_p = BoxSet('box_set')
class BoxGet(HiPrimitive):
multiple_results = True
def abstract_eval(self, box_ty, *, avals):
return avals, {box_effect}
def to_lojax(_, box, *, avals):
return tree_leaves(box._val)
def jvp(_, primals, tangents, *, avals):
(box,), (box_dot,) = primals, tangents
return (
box_get_p.bind(box, avals=avals),
box_get_p.bind(box_dot, avals=tuple(a.to_tangent_aval() for a in avals))
)
def transpose(_, *args):
assert False # TODO
box_get_p = BoxGet('box_get')