# --------------------------------------------------------------------------
# Copyright (c) Microsoft Corporation. All rights reserved.
# Licensed under the MIT License.
# --------------------------------------------------------------------------
from __future__ import annotations
from typing import Any
import numpy as np
import onnx
from ..quant_utils import (
TENSOR_NAME_QUANT_SUFFIX,
QuantizedValue,
QuantizedValueType,
attribute_to_kwarg,
quantize_nparray,
)
from .base_operator import QuantOperatorBase
from .qdq_base_operator import QDQOperatorBase
class QPad(QuantOperatorBase):
def __init__(self, onnx_quantizer, onnx_node):
super().__init__(onnx_quantizer, onnx_node)
def quantize(self):
node = self.node
assert node.op_type == "Pad"
# Only after version 11, it has the optional constant_value
# If input[0] is not quantized, do not quanitize this node
if (self.quantizer.opset_version < 11) or (node.input[0] not in self.quantizer.quantized_value_map):
super().quantize()
return
quantized_input_value = self.quantizer.quantized_value_map[node.input[0]]
kwargs = {}
for attribute in node.attribute:
kv = attribute_to_kwarg(attribute)
kwargs.update(kv)
if "mode" not in kwargs or kwargs["mode"] == b"constant":
if len(node.input) > 2 and node.input[2] != "": # There is 3rd input 'constant_value'
zp_tensor = self.quantizer.model.get_initializer(quantized_input_value.zp_name)
scale_tensor = self.quantizer.model.get_initializer(quantized_input_value.scale_name)
if zp_tensor is None or scale_tensor is None:
super().quantize()
return
padding_constant_initializer = self.quantizer.model.get_initializer(node.input[2])
if padding_constant_initializer is not None:
zp_array = onnx.numpy_helper.to_array(zp_tensor)
zp_value = zp_array.item() if zp_array.ndim == 0 else zp_array[0]
scale_array = onnx.numpy_helper.to_array(scale_tensor)
scale_value = scale_array.item() if scale_array.ndim == 0 else scale_array[0]
padding_constant_array = onnx.numpy_helper.to_array(padding_constant_initializer)
quantized_padding_constant_array = quantize_nparray(
self.quantizer.activation_qType,
padding_constant_array,
scale_value,
zp_value,
)
quantized_padding_constant_name = node.input[2] + TENSOR_NAME_QUANT_SUFFIX
quantized_padding_constant_initializer = onnx.numpy_helper.from_array(
quantized_padding_constant_array,
quantized_padding_constant_name,
)
# Suppose this padding constant initializer only used by the node
self.quantizer.model.remove_initializer(padding_constant_initializer)
self.quantizer.model.add_initializer(quantized_padding_constant_initializer)
node.input[2] = quantized_padding_constant_name
else:
# TODO: check quantize_inputs after sub graph is supported
pad_value_qnodes = self.quantizer._get_quantize_input_nodes(
node,
2,
self.quantizer.activation_qType,
quantized_input_value.scale_name,
quantized_input_value.zp_name,
initial_type=scale_tensor.data_type,
)
self.quantizer.new_nodes.extend(pad_value_qnodes)
node.input[2] = pad_value_qnodes[0].output[0]
else:
# In quantized format, the `zero` before quantization is mapped
# to quantized_input_value.zp_name. Thus, padding 0 to
# original tensor should become padding zero point to quantized
# tensor.
if len(node.input) == 2:
# Feed quantization's zero point to padding node.
node.input.append(quantized_input_value.zp_name)
else:
# Assign quantization's zero point to padding node.
assert node.input[2] == ""
node.input[2] = quantized_input_value.zp_name
# Create an entry for output quantized value
quantized_output_value = QuantizedValue(
node.output[0],
node.output[0] + TENSOR_NAME_QUANT_SUFFIX,
quantized_input_value.scale_name,
quantized_input_value.zp_name,
QuantizedValueType.Input,
)
self.quantizer.quantized_value_map[node.output[0]] = quantized_output_value
node.input[0] = quantized_input_value.q_name
node.output[0] = quantized_output_value.q_name
self.quantizer.new_nodes += [node]
class QDQPad(QDQOperatorBase):
def __init__(self, onnx_quantizer, onnx_node):
super().__init__(onnx_quantizer, onnx_node)
def _get_pad_const_val(self, attrs_dict: dict[str, Any]) -> np.ndarray | None:
"""
Returns the Pad's constant padding value. Returns `None` if the padding value is
not constant (i.e., comes from a dynamic input).
"""
const_val = None
onnx_tensor_type = self.quantizer.model.get_tensor_type(self.node.input[0])
if onnx_tensor_type is None:
return None
np_dtype = onnx.helper.tensor_dtype_to_np_dtype(onnx_tensor_type.elem_type)
if self.quantizer.opset_version < 11:
const_val = np.array(attrs_dict.get("value", 0), dtype=np_dtype)
elif len(self.node.input) >= 3 and self.node.input[2]:
const_val = self.quantizer.model.get_constant_value(self.node.input[2])
else:
const_val = np.array(0, dtype=np_dtype)
return const_val
def _should_quantize_output_same_as_input(self) -> bool:
"""
Returns true if Pad's output should use the same quantization parameters as input[0]
"""
attrs_dict = {}
for attribute in self.node.attribute:
kv = attribute_to_kwarg(attribute)
attrs_dict.update(kv)
pad_mode = attrs_dict.get("mode", b"constant")
if pad_mode in (b"reflect", b"edge", b"wrap"):
# These modes pad the output with a value that already exists in the input.
# So, we can quantize the output the same as the input.
return True
# For 'constant' mode, if padding with 0, we can also quantize the output the same as the input
# because our quantization floating-point range always includes 0.
if pad_mode == b"constant":
pad_val = self._get_pad_const_val(attrs_dict)
if pad_val is not None and pad_val.dtype in (np.float32, np.float16):
return float(pad_val.item()) == 0
return False
def quantize(self):
assert self.node.op_type == "Pad"
for input_name in self.node.input:
if input_name:
self.quantizer.quantize_activation_tensor(input_name)
if not self.disable_qdq_for_node_output:
if self._should_quantize_output_same_as_input():
self.quantizer.quantize_output_same_as_input(self.node.output[0], self.node.input[0], self.node.name)
else:
self.quantizer.quantize_activation_tensor(self.node.output[0])