ai-content-maker/.venv/Lib/site-packages/torch/ao/quantization/pt2e/utils.py

541 lines
21 KiB
Python

import operator
import types
import torch
from torch._export import capture_pre_autograd_graph
from torch.fx import (
GraphModule,
Node,
)
from torch.nn.utils.fusion import fuse_conv_bn_weights
from typing import Any, Callable, Dict, Optional, Tuple, List, Union
from torch.utils._pytree import LeafSpec
from torch.export.unflatten import _AttrKind, _assign_attr
# Makes sure that quantized_decomposed ops are registered
from torch.ao.quantization.fx._decomposed import quantized_decomposed_lib # noqa: F401
from torch.ao.quantization.quantizer import QuantizationAnnotation
__all__ = [
"fold_bn_weights_into_conv_node",
"get_aten_graph_module",
"remove_tensor_overload_for_qdq_ops",
]
_QUANTIZE_OPS = [
torch.ops.quantized_decomposed.quantize_per_tensor.default,
torch.ops.quantized_decomposed.quantize_per_tensor.tensor,
torch.ops.quantized_decomposed.quantize_per_channel.default,
]
_DEQUANTIZE_OPS = [
torch.ops.quantized_decomposed.dequantize_per_tensor.default,
torch.ops.quantized_decomposed.dequantize_per_tensor.tensor,
torch.ops.quantized_decomposed.dequantize_per_channel.default,
]
# Example inputs for conv-bn1d patterns
_conv1d_bn_example_inputs = (
torch.randn(1, 1, 3), # x
torch.randn(1, 1, 1), # conv_weight
torch.randn(1), # conv_bias
torch.randn(1), # bn_weight
torch.randn(1), # bn_bias
torch.randn(1), # bn_running_mean
torch.randn(1), # bn_running_var
)
# Example inputs for conv-bn2d patterns
_conv2d_bn_example_inputs = (
torch.randn(1, 1, 3, 3), # x
torch.randn(1, 1, 1, 1), # conv_weight
torch.randn(1), # conv_bias
torch.randn(1), # bn_weight
torch.randn(1), # bn_bias
torch.randn(1), # bn_running_mean
torch.randn(1), # bn_running_var
)
def _is_connected(source: torch.fx.Node, dest: torch.fx.Node) -> bool:
"""
Assuming dest is one of the ops inserted by quant workflow, this function
finds if source and dest are connected. Assumption is that only quant workflow
inserted ops exist between source and dest
"""
quant_workflow_ops = _QUANTIZE_OPS + _DEQUANTIZE_OPS
quant_workflow_ops.append(torch.ops.quantized_decomposed.choose_qparams.tensor)
while dest.target in quant_workflow_ops:
if not isinstance(dest.args[0], torch.fx.Node):
raise ValueError(f"expected arg[0] of quant workflow ops to be a node but found {dest.args[0]}")
dest = dest.args[0]
return (dest == source)
def _find_q_dq_node_for_user(
produer: torch.fx.Node, user: torch.fx.Node
) -> Tuple[Any, Any]:
"""
Find q, dq pair corresponding to [producer -> q -> dq -> user]
Utils works by finding dq arg of user and ensuring it is connected to
producer
"""
dq_node = None
for n in user.args:
if isinstance(n, torch.fx.Node) and n.op == "call_function" and n.target in _DEQUANTIZE_OPS:
if _is_connected(produer, n):
dq_node = n
break
if dq_node is None:
for n in user.kwargs:
if isinstance(n, torch.fx.Node) and n.op == "call_function" and n.target in _DEQUANTIZE_OPS:
if _is_connected(produer, n):
dq_node = n
break
if dq_node is None:
return (None, None)
q_node = None
if dq_node.args[0].op == "call_function" and dq_node.args[0].target in _QUANTIZE_OPS:
q_node = dq_node.args[0]
return (q_node, dq_node)
def _is_sym_size_node(node: Node):
return (
node.op == "call_function"
and node.target == torch.ops.aten.sym_size.default
or node.target == torch.ops.aten.sym_numel.default
or node.target == torch.ops.aten.sym_numel
or node.target == torch.ops.aten.sym_size
)
def _filter_sym_size_users(node: torch.fx.Node) -> List[torch.fx.Node]:
node_users = list(filter((lambda x: (_is_sym_size_node(x) is False)), node.users))
return node_users
def _is_valid_annotation(annotation: QuantizationAnnotation) -> bool:
if annotation is None:
return False
input_qspec_map = annotation.input_qspec_map
output_qspec = annotation.output_qspec
if len(input_qspec_map) == 0 and output_qspec is None:
return False
return True
def _get_tensor_constant_from_node(node, m):
if node is None:
return None
assert node.op == "get_attr"
target_atoms = node.target.split('.')
attr_itr = m
for i, atom in enumerate(target_atoms):
if not hasattr(attr_itr, atom):
raise RuntimeError(f"Node referenced nonexistent target {'.'.join(target_atoms[:i])}")
attr_itr = getattr(attr_itr, atom)
return attr_itr
def _get_all_arguments(orig_args, orig_kwargs, args_schema):
all_args = []
for i, schema in enumerate(args_schema):
if schema.name in orig_kwargs:
all_args.append(orig_kwargs[schema.name])
elif not schema.kwarg_only and i < len(orig_args):
all_args.append(orig_args[i])
else:
all_args.append(schema.default_value)
return all_args
def _is_supported_batch_norm_for_training(node: Node):
"""
Return True if the given node refers to an aten batch norm op QAT supports.
"""
supported_ops = [
torch.ops.aten._native_batch_norm_legit.default,
# Note: we won't need this op anymore after batch norm consolidation
# For now, we need to continue to support it because it gives better
# training numerics than `_native_batch_norm_legit`
torch.ops.aten.cudnn_batch_norm.default,
torch.ops.aten.miopen_batch_norm.default,
]
return node.target in supported_ops
# TODO: rename this to _is_conv_node
def _is_conv(n: Node):
"""
Return whether the node refers to an aten conv op.
"""
return n.op == "call_function" and n.target in [
torch.ops.aten.conv1d.default,
torch.ops.aten.conv2d.default,
]
# TODO: rename this to _is_conv_transpose_node
def _is_conv_transpose(n: Node):
"""
Return whether the node refers to an aten conv_transpose op.
"""
return n.op == "call_function" and n.target in [
torch.ops.aten.conv_transpose1d,
torch.ops.aten.conv_transpose2d,
]
def _is_bn_node(n: Node):
return _is_supported_batch_norm_for_training(n) or n.target == torch.ops.aten._native_batch_norm_legit_no_training.default
def fold_bn_weights_into_conv_node(
conv_node: Node,
conv_weight_node: Node,
conv_bias_node: Optional[Node],
bn_node: Node,
m: GraphModule
) -> None:
# conv args: input, weight, bias, stride, padding, dilation, ...
conv_w = _get_tensor_constant_from_node(conv_weight_node, m)
conv_b = _get_tensor_constant_from_node(conv_bias_node, m)
transpose = _is_conv_transpose(conv_node)
# eval bn args: input, weight, bias, running mean, running var, momentum, eps
# train bn args: input, weight, bias, running mean, running var, training, momentum, eps
bn_args_schema = bn_node.target._schema.arguments # type: ignore[union-attr]
bn_args = _get_all_arguments(bn_node.args, bn_node.kwargs, bn_args_schema)
bn_w = _get_tensor_constant_from_node(bn_args[1], m)
bn_b = _get_tensor_constant_from_node(bn_args[2], m)
bn_rm = _get_tensor_constant_from_node(bn_args[3], m)
bn_rv = _get_tensor_constant_from_node(bn_args[4], m)
if bn_node.target == torch.ops.aten._native_batch_norm_legit_no_training.default:
eps_arg_index = 6
elif _is_supported_batch_norm_for_training(bn_node):
eps_arg_index = 7
else:
raise ValueError("BN node target is unexpected ", bn_node.target)
bn_eps = bn_args[eps_arg_index]
fused_weight, fused_bias = fuse_conv_bn_weights(conv_w, conv_b, bn_rm, bn_rv, bn_eps, bn_w, bn_b, transpose=transpose)
# update the weight and bias for conv
conv_args = list(conv_node.args)
# filling in the default bias argument
if len(conv_args) == 2:
conv_args.append(None)
# calling data since the fused_weight and fused_bias are nn.Parameter
weight_attr_name = conv_weight_node.target
assert isinstance(weight_attr_name, str)
_assign_attr(fused_weight, m, weight_attr_name, _AttrKind.PARAMETER)
if conv_bias_node is not None:
bias_attr_name = conv_bias_node.target
_assign_attr(fused_bias, m, str(bias_attr_name), _AttrKind.PARAMETER)
else:
bias_attr_name = weight_attr_name + "_bias"
_assign_attr(fused_bias, m, bias_attr_name, _AttrKind.PARAMETER)
with m.graph.inserting_before(conv_node):
get_bias_node = m.graph.get_attr(bias_attr_name)
# NOTE: here we assume the bias of conv is not quantized!
conv_args[2] = get_bias_node
conv_node.args = tuple(conv_args)
# native_batch_norm has 3 outputs, we expect getitem calls on the output
# and we want to replace the uses of getitem 0 with the output of conv
#
# Before:
# conv -> bn - (first output) -> users1
# \ - (second output) -> users2
# \ - (third output) -> users3
# After:
# conv -> (first output) -> users1
# bn -
# \ - (second output) -> users2
# \ - (third output) -> users3
# if users2 and users3 are empty then bn will be removed through dead code elimination
for user in bn_node.users:
if user.op != "call_function" or user.target != operator.getitem or user.args[1] != 0:
continue
user.replace_all_uses_with(conv_node)
# fuse conv bn weights, inplace modification of the graph_module and graph
def _fuse_conv_bn_(m: GraphModule) -> None:
has_bn = any(_is_bn_node(n) for n in m.graph.nodes)
if not has_bn:
return
for n in m.graph.nodes:
if n.op != "call_function" or n.target != torch.ops.aten._native_batch_norm_legit_no_training.default:
continue
bn_node = n
n = bn_node.args[0]
if not _is_conv(n):
continue
conv_node = n
conv_weight_node = conv_node.args[1]
conv_bias_node = conv_node.args[2] if len(conv_node.args) > 2 else None
fold_bn_weights_into_conv_node(conv_node, conv_weight_node, conv_bias_node, bn_node, m)
m.graph.eliminate_dead_code()
m.recompile()
def _get_node_name_to_scope(model: GraphModule) -> Dict[str, Tuple[str, type]]:
# TODO: move this information to fx node itself
node_name_to_scope: Dict[str, Tuple[str, type]] = {}
for n in model.graph.nodes:
nn_module_stack = n.meta.get("nn_module_stack", None)
current_scope = ("", type(None))
if nn_module_stack:
bt = list(nn_module_stack.values())[-1]
current_scope = (bt[0].split(".")[-1], bt[1])
node_name_to_scope[n.name] = current_scope
return node_name_to_scope
def get_aten_graph_module(
pattern: Callable,
example_inputs: Tuple[Any, ...],
is_cuda: bool = False,
**kwargs,
) -> GraphModule:
"""
Convert the pattern to an FX graph with decomposed aten ops.
"""
if is_cuda:
example_inputs = tuple([x.cuda() if isinstance(x, torch.Tensor) else x for x in example_inputs])
aten_pattern = capture_pre_autograd_graph(
pattern,
example_inputs,
kwargs,
)
aten_pattern.graph.eliminate_dead_code()
aten_pattern.recompile()
return aten_pattern
def remove_tensor_overload_for_qdq_ops(match_pattern: GraphModule) -> None:
""" Remove .tensor overload for quantize/dequantize ops so that we can
use the match_pattern that we get from torchdynamo export to match the output of convert_pt2e
"""
_MAP = {
torch.ops.quantized_decomposed.quantize_per_tensor.default: torch.ops.quantized_decomposed.quantize_per_tensor,
torch.ops.quantized_decomposed.dequantize_per_tensor.default: torch.ops.quantized_decomposed.dequantize_per_tensor,
torch.ops.quantized_decomposed.quantize_per_tensor.tensor: torch.ops.quantized_decomposed.quantize_per_tensor,
torch.ops.quantized_decomposed.dequantize_per_tensor.tensor: torch.ops.quantized_decomposed.dequantize_per_tensor,
torch.ops.quantized_decomposed.quantize_per_tensor.tensor2: torch.ops.quantized_decomposed.quantize_per_tensor,
torch.ops.quantized_decomposed.dequantize_per_tensor.tensor2: torch.ops.quantized_decomposed.dequantize_per_tensor,
torch.ops.quantized_decomposed.quantize_per_channel.default: torch.ops.quantized_decomposed.quantize_per_channel,
torch.ops.quantized_decomposed.dequantize_per_channel.default: torch.ops.quantized_decomposed.dequantize_per_channel,
torch.ops.aten.clamp.Tensor: torch.ops.aten.clamp,
}
for n in match_pattern.graph.nodes:
if n.op != "call_function":
continue
if n.target in _MAP:
n.target = _MAP[n.target]
def _is_literal(arg):
if isinstance(arg, (int, float)):
return True
if isinstance(arg, (tuple, list)):
return all(map(_is_literal, arg))
return False
def _replace_literals_with_new_placeholders(
gm: torch.fx.GraphModule,
merge_dup: bool = False,
exclude_literals: Optional[List[Any]] = None
):
"""Replace the literals in the graph with placeholder nodes that's created on the fly while we
traverse the graph, so that the literal arguments in the graph can be matched and replaced
To use this, the pattern and replacement graph should have the exact same number of literal args
and they should be used in the exact same order in the pattern and replacement graph.
If the literal arguments are not used in the same order in pattern and replacement graph, please
use `_replace_literals_with_existing_placeholders` instead
Args:
`gm`: input GraphModule that we'll transform
`merge_dup`: boolean flag to indicate that if the same literal appears multiple times in
the graph, whether they should correspond to the same placeholder or not
`exclude_literals`: a list of literals that will not be replaced with placeholders
Example:
# 1. Original Graph
def pattern(self, x):
return x + 3
def replacement(self, x):
return x - 3
example_inputs = (torch.randn(1, 3, 3, 3),)
pattern_gm = get_aten_graph_module(pattern, example_inputs)
replacement_gm = get_aten_graph_module(pattern, example_inptus)
# 2. Before calling replace literals we'll see the following graph:
def pattern(self, x):
return x + 3
def replacement(self, x):
return x - 3
pattern_gm = _replace_literals_with_new_placeholders(pattern_gm)
replacement_gm = _replace_literals_with_new_placeholders(replacement_gm)
# 3. After replacing literals with new placeholder nodes
def pattern(self, x, new_ph):
return x + new_ph
def pattern(self, x, new_ph):
return x - new_ph
"""
last_ph = None
cnt = 0
literal_to_ph: Dict[Union[float, bool, int, torch.dtype], Node] = {}
if exclude_literals is None:
exclude_literals = []
in_spec = gm._in_spec
args_spec = in_spec.children_specs[0]
for node in gm.graph.nodes:
if node.op == "placeholder":
last_ph = node
cnt += 1
continue
with gm.graph.inserting_after(last_ph):
new_args = []
for arg in node.args:
if _is_literal(arg) and arg not in exclude_literals:
if merge_dup and arg in literal_to_ph:
new_args.append(literal_to_ph[arg])
else:
ph_node = gm.graph.placeholder("arg" + str(cnt))
new_args.append(ph_node)
args_spec.children_specs.append(LeafSpec())
cnt += 1
if merge_dup:
literal_to_ph[arg] = ph_node
else:
new_args.append(arg)
new_args = tuple(new_args)
node.args = new_args
# Update `num_nodes`, `num_leaves`, `num_children`.
args_spec.__post_init__()
in_spec.__post_init__()
return gm
def _replace_literals_with_existing_placeholders(
gm: torch.fx.GraphModule,
exclude_literals: Optional[List[Any]] = None,
literal_to_ph_idx: Optional[Dict[Union[float, int, bool, torch.dtype], int]] = None
):
"""Replace the literals in the graph with **existing** placeholder nodes, so that the literal arguments
in the graph can be matched and replaced
To use this, all literal args in the graph should be unique and each of them should correspond
to exactly one placeholder node
# 1. Original Graph
def pattern(self, x_i8, scale, zero_point, quant_min, quant_max):
return torch.dequantize_per_tensor(x_i8, scale, zero_point, quant_min, quant_max)
def replacement(x_i8, scale, zero_point, quant_min, quant_max):
x_i8 = torch.clamp(x_i8, quant_min, quant_max)
return ((x_i8.to(torch.float32) - zero_point) * scale).to(dtype=torch.float32)
example_inputs = (
torch.randn(1, 3, 3, 3),
1.0,
0,
-128,
127,
)
pattern_gm = get_aten_graph_module(pattern, example_inputs)
replacement_gm = get_aten_graph_module(pattern, example_inptus)
# 2. Before calling replace literals we'll see the following graph:
def pattern(self, x_i8, scale, zero_point, quant_min, quant_max):
# scale/zero_point/quant_min/quant_max are burnt in since they are scalar values
return torch.dequantize_per_tensor(x_i8, 1.0, 0, -128, 127)
def replacement(x_i8, scale, zero_point, quant_min, quant_max):
# scale/zero_point/quant_min/quant_max are burnt in since they are scalar values
x_i8 = torch.clamp(x_i8, -128, 127)
return ((x_i8.to(torch.float32) - 0) * 1.0).to(dtype=torch.float32)
# Note that literal args appear in different order in pattern and replacement graph, so
# we can't use _replace_literals_with_new_placeholders
literal_to_ph_idx = {1.0: 1, 0: 2, -128: 3, 127: 4}
pattern_gm = _replace_literals_with_existing_placeholders(pattern_gm, literal_to_ph_idx)
replacement_gm = _replace_literals_with_existing_placeholders(replacement_gm, literal_to_ph_idx)
# 3. After replacing literals with existing placeholder nodes
def pattern(self, x_i8, scale, zero_point, quant_min, quant_max):
# scale/zero_point/quant_min/quant_max are burnt in since they are scalar values
return torch.dequantize_per_tensor(x_i8, scale, zero_point, quant_min, quant_max)
def replacement(x_i8, scale, zero_point, quant_min, quant_max):
# scale/zero_point/quant_min/quant_max are burnt in since they are scalar values
x_i8 = torch.clamp(x_i8, quant_min, quant_max)
return ((x_i8.to(torch.float32) - zero_point) * scale).to(dtype=torch.float32)
"""
if exclude_literals is None:
exclude_literals = []
if literal_to_ph_idx is None:
literal_to_ph_idx = {}
phs = [node for node in gm.graph.nodes if node.op == "placeholder"]
for node in gm.graph.nodes:
if node.op != "call_function":
continue
new_args = []
for arg in node.args:
if _is_literal(arg) and arg not in exclude_literals and arg in literal_to_ph_idx:
ph_idx = literal_to_ph_idx[arg]
ph_node = phs[ph_idx]
new_args.append(ph_node)
else:
new_args.append(arg)
new_args = tuple(new_args)
node.args = new_args
return gm
# TODO: Handle this in export itself and don't wrap the model in another GraphModule
# in prepare and convert
def _disallow_eval_train(model: GraphModule):
"""
Disallow calling `model.train()` or `model.eval()` on the given GraphModule.
This is useful for exported models, where these methods don't actually behave as expected.
"""
error_message = \
"""
Calling train() or eval() is not supported for exported models.
Please call `torch.ao.quantization.move_exported_model_to_train(model)` (or eval) instead.
If you cannot replace the calls to `model.train()` and `model.eval()`, you may override
the behavior for these methods by calling `torch.ao.quantization.allow_exported_model_train_eval(model)`,
which does the above automatically for you. Note that this has limited effect on switching
behavior between train and eval modes, and should be used only for special ops such as dropout
and batchnorm.
"""
def _train(self, mode: bool = True):
raise NotImplementedError(error_message)
def _eval(self, mode: bool = True):
raise NotImplementedError(error_message)
model.train = types.MethodType(_train, model) # type: ignore[method-assign]
model.eval = types.MethodType(_eval, model) # type: ignore[method-assign]
return model