# pylint: disable=import-outside-toplevel, simplifiable-if-expression, unnecessary-comprehension
"""PT: PyTorch frontend."""
import itertools
+import logging
import numpy as np
from .common import infer_shape as _infer_shape
from .common import infer_value as _infer_value
+from . import qnn_torch
+
__all__ = ["from_pytorch"]
# operator implementation
def _relu():
def _impl(inputs, input_types):
data = inputs[0]
+ if input_types[0] == "quint8":
+ assert len(inputs) == 3, "Input quant param not found in op inputs"
+ input_zero_point = _expr.const(inputs[2], dtype="int32")
+ return qnn_torch.quantized_relu(data, input_zero_point)
return _op.nn.relu(data)
return _impl
data = inputs[0]
output_size = _infer_shape(inputs[1])
- return _op.nn.adaptive_avg_pool2d(
- data,
- output_size=output_size)
+ def func(x):
+ return _op.nn.adaptive_avg_pool2d(x, output_size=output_size)
+
+ if input_types[0] == "quint8":
+ return qnn_torch.quantized_adaptive_avg_2d(data, func)
+
+ return func(data)
+
return _impl
def _adaptive_max_2d():
else:
exclude = False
- return _op.mean(data, axis, keepdims, exclude)
+ def func(x):
+ return _op.mean(x, axis, keepdims, exclude)
+
+ if input_types[0] == "quint8":
+ assert len(inputs) == 6, "Input quant param not found in op inputs"
+ input_scale = _expr.const(inputs[4])
+ input_zero_point = _expr.const(inputs[5])
+ return qnn_torch.quantized_mean(data, input_scale,
+ input_zero_point, func)
+
+ return func(data)
+
return _impl
def _chunk():
else:
coord_trans = "half_pixel"
- return _op.image.resize(data, out_size, "NCHW", method, coord_trans)
+ def func(x):
+ return _op.image.resize(x, out_size, "NCHW", method, coord_trans)
+
+ if input_types[0] == "quint8":
+ import torch
+ from packaging import version
+
+ # Torch version > 1.4 changed upsampling API
+ if version.parse(torch.__version__) > version.parse("1.4.0"):
+ num_inputs = 7
+ else:
+ num_inputs = 5
+
+ assert len(inputs) == num_inputs, "Input quant param not found in op inputs"
+
+ input_scale = _expr.const(inputs[-2])
+ input_zero_point = _expr.const(inputs[-1])
+ return qnn_torch.quantized_upsample(data, input_scale,
+ input_zero_point, func)
+ return func(data)
return _impl
+
+def _expand_as():
+ def _impl(inputs, input_types):
+ # TODO: maybe fix this
+ # This assumes expand_as can be removed because TVM has broadcast op
+ msg = "aten::expand_as(...) found, assume it is part of broadcast op"
+ logging.warning(msg)
+ return inputs[0]
+ return _impl
+
+
# Helper functions for operator implementation
def _convert_data_type(input_type):
"aten::detach" : _identity(),
"aten::upsample_bilinear2d" : _upsample("bilinear"),
"aten::upsample_nearest2d" : _upsample("nearest_neighbor"),
+ "aten::expand_as" : _expand_as()
}
"prim::ListConstruct", "prim::ListUnpack",
"prim::TupleConstruct", "prim::TupleUnpack"]
known_ops += list(_convert_map.keys())
+ known_ops += list(qnn_torch.convert_map.keys())
missing = [op_name for op_name in op_names
if op_name not in known_ops]
getattr_nodes = graph.findAllNodes("prim::GetAttr", recurse=True)
params = {}
param_tensors = {}
+ packed_param_map = {}
seen = set()
for node in getattr_nodes:
full_attr = _getattr_full_name(getattrs)
full_attr_node_name = _get_output_name(getattrs[-1])
- if full_attr in state_dict:
+ if full_attr.endswith("_packed_params"): # for quantized models
+ err_msg = "parameter %s not found in state dict" % full_attr
+ assert full_attr in state_dict, err_msg
+ packed_param_map[full_attr_node_name] = full_attr
+ elif full_attr in state_dict:
torch_tensor = state_dict[full_attr]
tensor, var = _get_tensor_and_var(torch_tensor,
full_attr_node_name)
param_tensors[full_attr_node_name] = tensor
params[full_attr_node_name] = var
- return params, param_tensors
+ return params, param_tensors, packed_param_map
def parse_operators(operators, outputs, output_index_map, ret_name):
params = script_module.state_dict()
input_vars = parse_inputs(graph.inputs(), input_shapes)
- param_vars, tensors = parse_params(graph, params)
+ param_vars, tensors, packed_param_map = parse_params(graph, params)
+ tvm_params = {k: tvm.nd.array(v) for k, v in tensors.items()}
input_vars.update(param_vars)
outputs = list(input_vars.values())
output_index_map = dict(zip(input_vars.keys(), range(len(outputs))))
ret_name = _get_input_names(graph.return_node())[0]
+ # For quantized models
+ if "aten::quantize_per_tensor" in op_names:
+ weight_quant_params = qnn_torch.get_weight_quant_params(script_module)
+ qnn_torch.add_input_quant_params_to_op_inputs(graph)
+ qnn_torch.add_quant_params_to_outputs(outputs, output_index_map,
+ packed_param_map,
+ weight_quant_params)
+ qnn_torch.add_quant_params(tvm_params, weight_quant_params)
+ _convert_map.update(qnn_torch.convert_map)
+
body = parse_operators(_get_operator_nodes(graph.nodes()), outputs,
output_index_map, ret_name)
func = tvm.relay.Function(_analysis.free_vars(body), body)
- tvm_params = {k: tvm.nd.array(v) for k, v in tensors.items()}
return _module.IRModule.from_expr(func), tvm_params
--- /dev/null
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements. See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership. The ASF licenses this file
+# to you 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
+#
+# http://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.
+# pylint: disable=invalid-name, import-outside-toplevel
+""" Functions to convert quantized torch models to QNN """
+
+import numpy as np
+
+import tvm
+from tvm import relay
+from tvm.relay import expr as _expr
+from tvm.relay import op as _op
+from tvm.relay.frontend.common import infer_shape
+
+
+class QNNParam:
+ """ A placeholder for weight quantization parameters """
+
+ def __init__(self, weight, bias, scale, zero_point, param_key):
+ param_prefix = param_key[:-len("._packed_params")]
+ self.weight_var = _expr.var(param_prefix + "_weight",
+ shape=weight.shape)
+ self.weight = weight
+
+ if bias is not None:
+ self.bias_var = _expr.var(param_prefix + "_bias",
+ shape=bias.shape)
+ self.bias = bias.detach().numpy()
+ else:
+ self.bias_var = None
+ self.bias = None
+
+ self.scale = _expr.const(scale)
+ self.zero_point = _expr.const(zero_point, dtype="int32")
+
+
+def _unpack_quant_params(param_name, packed_params, unpack_func):
+ # Torch stores quantized params in a custom packed format,
+ # need to unpack and retrieve them as numpy arrays
+ qweight, bias = unpack_func(packed_params)
+ weight_np = qweight.dequantize().numpy()
+
+ import torch
+ if qweight.qscheme() == torch.per_tensor_affine:
+ param = QNNParam(weight_np, bias, qweight.q_scale(),
+ int(qweight.q_zero_point()), param_name)
+ else:
+ scales = qweight.q_per_channel_scales().numpy()
+ zero_points = qweight.q_per_channel_zero_points().numpy()
+ # This is an assumption posed by QNN
+ msg = "The values of zero points should be all zero for per channel"
+ assert np.all(zero_points == 0), msg
+ param = QNNParam(weight_np, bias, scales, 0, param_name)
+
+ return param
+
+
+def get_weight_quant_params(script_module):
+ """ Retrive and unpack weight parameters from quantized modules """
+ conv_packed_params = []
+ linear_packed_params = []
+
+ import torch
+ # conv and linear requires different unpacking function
+ # extract all conv and linear parameters separately to distinguish them
+ for name, m in script_module.named_modules():
+ if isinstance(m, torch.jit.RecursiveScriptModule):
+ if "Conv" in m.original_name:
+ conv_packed_params.append((name, m.state_dict()))
+ elif m.original_name == "LinearPackedParams":
+ linear_packed_params.append((name, m.state_dict()))
+
+ pairs = [(torch.ops.quantized.conv2d_unpack, conv_packed_params),
+ (torch.ops.quantized.linear_unpack, linear_packed_params)]
+
+ quant_params = {}
+ param_name = "_packed_params"
+ for unpack_func, params in pairs:
+ for name, state_dict in params:
+ assert len(state_dict) == 1
+ assert param_name in state_dict
+ key = name + "." + param_name
+ packed_param = state_dict[param_name]
+ quant_params[key] = _unpack_quant_params(key, packed_param,
+ unpack_func)
+
+ return quant_params
+
+
+def add_quant_params_to_outputs(outputs, output_index_map,
+ packed_param_map, quant_params):
+ """
+ Add quant params to outputs so that they can be referenced by other
+ ops later. Weights are quantized here.
+ """
+ for node_name, packed_param_name in packed_param_map.items():
+ qparam = quant_params[packed_param_name]
+ output_index_map[node_name] = len(outputs)
+ qweight = relay.qnn.op.quantize(qparam.weight_var, qparam.scale,
+ qparam.zero_point, out_dtype="int8",
+ axis=0)
+ param_tup = (qweight, qparam.scale, qparam.zero_point, qparam.bias_var)
+ outputs.append(param_tup)
+
+
+def _get_quant_param_for_input(input_value):
+ """
+ We want to know the input scale and zp of this input_value, since
+ input quant params are not explicitly passed around in torch (they
+ are embeded in a QTensor data structure, not visible statically).
+ We know that it is quantized using output scale and zp
+ of some previous quantized op. The purpose of this function
+ is to find that pair of parameters.
+ """
+ # Indices for output scale and zp
+ # For example, in quantized::conv2d(%input, %1, %2, %3, %4, %5, %6, %7),
+ # 6th and 7th arg are output scale and zp respectively.
+ output_quant_param_indices = {
+ "aten::quantize_per_tensor": (1, 2),
+ "quantized::conv2d": (6, 7),
+ "quantized::conv2d_relu": (6, 7),
+ "quantized::linear": (2, 3),
+ "quantized::linear_relu": (2, 3),
+ "quantized::add_relu": (2, 3),
+ "quantized::add": (2, 3),
+ "quantized::mul_relu": (2, 3),
+ "quantized::mul": (2, 3),
+ "quantized::cat": (2, 3),
+ "quantized::mul_scalar": (2, 3),
+ "quantized::add_scalar": (2, 3)
+ }
+
+ def dfs(current_node):
+ # trace back to find the producer of this input value
+ current_op = current_node.kind()
+ if current_op in output_quant_param_indices:
+ indices = output_quant_param_indices[current_op]
+ scale = current_node.inputsAt(indices[0])
+ zp = current_node.inputsAt(indices[1])
+ return scale, zp
+
+ # Trace back eariler nodes, dfs order
+ # Assume quantized tensor comes earlier in the args
+ for arg in current_node.inputs():
+ return dfs(arg.node())
+
+ # shouldn't happen
+ assert False, "No producer for %s" % (str(current_node))
+
+ return dfs(input_value.node())
+
+
+def _get_add_scalar_output_quant_param(input_scale, input_zero_point,
+ scalar):
+ """
+ Determine the output scale and zp of quantized::add_scalar op
+ This is used for mobilenet v3
+ Refer to aten/src/ATen/native/quantized/cpu/qadd.cpp
+ The names of variables are the same as torch impl
+ """
+ q_min = 0
+ q_max = 255
+ s = input_scale
+ z = input_zero_point
+ c = scalar
+ c_q = round(c / s)
+
+ if q_min > z - c_q:
+ s_prime = (float(q_max) - (z - c_q)) / (float(q_max) - q_min) * s
+ z_prime = q_min
+ elif q_max < z - c_q:
+ s_prime = (float(z - c_q) - q_min) / (float(q_max) - q_min) * s
+ z_prime = q_max
+ else:
+ s_prime = s
+ z_prime = z - c_q
+
+ return s_prime, z_prime
+
+
+def _get_mul_scalar_output_quant_param(input_scale, input_zero_point,
+ scalar):
+ """
+ Determine the output scale and zp of quantized::mul_scalar op
+ This is used for mobilenet v3
+ Refer to aten/src/ATen/native/quantized/cpu/qmul.cpp
+ The names of variables are the same as torch impl
+ """
+ q_min = 0
+ q_max = 255
+ self_scale = input_scale
+ self_zero_point = input_zero_point
+ other_val = scalar
+
+ if other_val > 0.0:
+ s_prime = other_val * self_scale
+ z_prime = self_zero_point
+ elif other_val == 0.0:
+ s_prime = 1.0
+ z_prime = 0
+ else:
+ s_prime = abs(other_val) * self_scale
+ z_prime = q_max - (self_zero_point - q_min)
+
+ return s_prime, z_prime
+
+
+def _add_output_quant_params_to_scalar_op(node, graph,
+ input_scale, input_zero_point,
+ scalar):
+ """
+ The output scale and zp of {add,mul}_scalar op are not explicit in the IR
+ They are required for _get_quant_param_for_input above to work correctly
+ So calculate these params using the same way torch does, and make new
+ constant nodes in the input IR. Also add these params to the inputs of
+ scalar op.
+
+ For example,
+ %6 : float = prim::Constant[value=3.]()
+ %input : QUInt8(1, 3, 224, 224) = quantized::add_scalar(%x.1, %6)
+ becomes
+ %6 : float = prim::Constant[value=3.]()
+ %7 : float = prim::Constant[value=0.015686161816120148]()
+ %8 : int = prim::Constant[value=0]()
+ %input : UInt8(1, 3, 224, 224) = quantized::add_scalar(%x.1, %6, %7, %8)
+
+ %7 and %8 are newly created output scale and zp constant nodes
+ """
+ import torch
+ operator = node.kind()
+
+ if operator == "quantized::mul_scalar":
+ out_scale, out_zero_point = \
+ _get_mul_scalar_output_quant_param(input_scale, input_zero_point,
+ scalar)
+ elif operator == "quantized::add_scalar":
+ out_scale, out_zero_point = \
+ _get_add_scalar_output_quant_param(input_scale, input_zero_point,
+ scalar)
+ else:
+ raise NotImplementedError("unsupported scalar op: %s" % operator)
+
+ # create new constant nodes and add them to graph
+ out_scale_node = graph.create("prim::Constant")
+ out_zero_point_node = graph.create("prim::Constant")
+ out_scale_node.insertBefore(node)
+ out_zero_point_node.insertBefore(node)
+ out_scale_node.f_("value", out_scale)
+ out_zero_point_node.i_("value", out_zero_point)
+ out_scale_node.output().setType(torch._C.FloatType.get())
+ out_zero_point_node.output().setType(torch._C.IntType.get())
+ node.addInput(out_scale_node.output())
+ node.addInput(out_zero_point_node.output())
+
+
+def add_input_quant_params_to_op_inputs(graph):
+ """
+ In Torch, input quant params are not explicitly passed around
+ Instead, they are stored in QTensor data structure, and retrieved
+ at runtime by each quantized ops.
+ However, they need to be known statically for QNN translation.
+ To workaround and simplify the translation of inputs, we manually add
+ input quant params to inputs of Torch quantized operators listed below.
+ See _quantized_conv2d() below for example of why this is helpful.
+
+ For example,
+ %input : QUInt8(1, 512, 7, 7) = quantized::add(%x.8, %x.9, %434, %435)
+ becomes
+ %395 : float = prim::Constant[value=0.036212071776390076]()
+ %396 : int = prim::Constant[value=0]()
+ %430 : float = prim::Constant[value=0.16080744564533234]()
+ %431 : int = prim::Constant[value=42]()
+ %input : QUInt8(1, 512, 7, 7) = quantized::add(%x.8, %x.9, %434, %435,
+ %430, %431, %395, %396)
+
+ %434, %435 are output scale and zp of quantized::add op
+ %430, %431, %395, %396 are two pairs of input (scale, zp) for two tensors
+ added by this function
+ """
+ # How many quantized tensors each op takes as inputs?
+ # A pair of (scale, zp) for each input quantized tensor will be added
+ # to the input nodes
+ num_quantized_inputs = {"quantized::conv2d": 1,
+ "quantized::conv2d_relu": 1,
+ "quantized::linear": 1,
+ "quantized::linear_relu": 1,
+ "quantized::add_relu": 2,
+ "quantized::add": 2,
+ "quantized::mul_relu": 2,
+ "quantized::mul": 2,
+ "aten::dequantize": 1,
+ "aten::mean": 1,
+ "aten::upsample_bilinear2d": 1,
+ "aten::relu_": 1,
+ "aten::relu": 1,
+ "quantized::add_scalar": 1,
+ "quantized::mul_scalar": 1,
+ 'quantized::relu6': 1}
+
+ need_input_quant_param = set(num_quantized_inputs.keys())
+ need_input_quant_param.add("quantized::cat")
+
+ for node in graph.nodes():
+ operator = node.kind()
+ if operator not in need_input_quant_param:
+ continue
+
+ input_scales = []
+ input_zero_points = []
+
+ if operator == "quantized::cat":
+ # the number of inputs to concat is not constant
+ # so handle it separately
+ inputs = node.inputsAt(0).node().inputs()
+ for inp in inputs:
+ scale, zp = _get_quant_param_for_input(inp)
+ input_scales.append(scale)
+ input_zero_points.append(zp)
+ else:
+ for i in range(num_quantized_inputs[operator]):
+ scale, zp = _get_quant_param_for_input(node.inputsAt(i))
+ input_scales.append(scale)
+ input_zero_points.append(zp)
+
+ if operator in ["quantized::add_scalar", "quantized::mul_scalar"]:
+ scalar = node.inputsAt(1).node().f("value")
+ inp_scale = input_scales[0].node().f("value")
+ inp_zero_point = input_zero_points[0].node().i("value")
+
+ # see the comments in this function above
+ _add_output_quant_params_to_scalar_op(node, graph,
+ inp_scale, inp_zero_point,
+ scalar)
+
+ for scale, zp in zip(input_scales, input_zero_points):
+ node.addInput(scale)
+ node.addInput(zp)
+
+
+def add_quant_params(params, quant_params):
+ """ Add quant parameters to TVM param map """
+ for qparam in quant_params.values():
+ params[qparam.weight_var.name_hint] = tvm.nd.array(qparam.weight)
+ if qparam.bias is not None:
+ params[qparam.bias_var.name_hint] = tvm.nd.array(qparam.bias)
+
+
+def quantized_adaptive_avg_2d(data, func_fp32):
+ # this follows tflite impl
+ inp = _op.cast(data, dtype="int32")
+ out = func_fp32(inp)
+ return _op.cast(out, "uint8")
+
+
+def quantized_mean(data, input_scale, input_zero_point, func_fp32):
+ # refer to aten/src/ATen/native/quantized/cpu/qreduction.cpp
+ dequantized = relay.qnn.op.dequantize(data, input_scale, input_zero_point)
+ out = func_fp32(dequantized)
+ return relay.qnn.op.quantize(out, input_scale, input_zero_point,
+ out_dtype="uint8", axis=1)
+
+
+def quantized_upsample(data, input_scale, input_zero_point, func_fp32):
+ # currently piggy backs to fp32, it gets identical output as torch
+ data = relay.qnn.op.dequantize(data, input_scale, input_zero_point)
+ out = func_fp32(data)
+ return relay.qnn.op.quantize(out, input_scale, input_zero_point,
+ out_dtype="uint8", axis=1)
+
+
+def quantized_relu(data, input_zero_point):
+ # refer to aten/src/ATen/native/quantized/cpu/qrelu.cpp
+ zp = _op.cast(input_zero_point, dtype="uint8")
+ return _op.tensor.maximum(data, zp)
+
+
+def _quantize_per_tensor():
+ def _impl(inputs, _):
+ return relay.qnn.op.quantize(inputs[0], _expr.const(inputs[1]),
+ _expr.const(inputs[2]), out_dtype="uint8",
+ axis=1)
+ return _impl
+
+
+def _dequantize():
+ def _impl(inputs, _):
+ assert len(inputs) == 3, "Input quant params not found in op inputs"
+ inp_scale = _expr.const(inputs[1])
+ inp_zero_point = _expr.const(inputs[2])
+ return relay.qnn.op.dequantize(inputs[0], inp_scale, inp_zero_point)
+ return _impl
+
+
+def _get_numpy(relay_const_scalar):
+ return relay_const_scalar.data.asnumpy()
+
+
+def _get_scalar(relay_const_scalar):
+ return np.asscalar(_get_numpy(relay_const_scalar))
+
+
+def _do_bias_and_requantize(output, bias, input_scale, weight_scale,
+ output_scale, output_zero_point,
+ with_relu):
+ """ Output processing for conv and linear """
+ # this is a vector for per channel case
+ requant_input_scale = _expr.const(_get_numpy(input_scale) *
+ _get_numpy(weight_scale))
+ # Torch does bias add and requanize scale in fp32
+ # refer to third_party/fbgemm/include/fbgemm/OutputProcessing-inl.h
+ # Instead, we do bias add in int32 and use qnn requantize, which needs
+ # integer input.
+ # We observed no loss in accuracy in doing this way, and it is better
+ # for tvm because bias quantization can be done at compile time
+ # Instead, the torch way requires rounding of activation at runtime
+
+ if bias is not None:
+ qbias = relay.qnn.op.quantize(bias, requant_input_scale,
+ _expr.const(0, "int32"),
+ out_dtype="int32", axis=0)
+ requantize_input = _op.nn.bias_add(output, qbias)
+ else:
+ requantize_input = output
+
+ requantized = relay.qnn.op.requantize(requantize_input,
+ requant_input_scale,
+ relay.const(0, 'int32'),
+ output_scale, output_zero_point,
+ out_dtype="int32", axis=1)
+ clip_min = 0
+ if with_relu:
+ clip_min = _get_scalar(output_zero_point)
+
+ clip = _op.tensor.clip(requantized, clip_min, 255.)
+ return _op.cast(clip, dtype="uint8")
+
+
+def _quantized_conv2d(with_relu=False):
+ def _impl(inputs, _):
+ # refer to src/ATen/native/quantized/cpu/qconv.cpp
+ # inputs[0]: input tensor
+ # inputs[1]: (weight, scale, zero_point, bias)
+ # inputs[2-5]: stride, padding, dilation, groups
+ # inputs[6]: output_scale
+ # inputs[7]: output_zero_point
+ # inputs[8]: input_scale (added manually by frontend)
+ # inputs[9]: input_zero_point (added manually by frontend)
+ weight = inputs[1][0]
+ weight_scale = inputs[1][1]
+ weight_zero_point = inputs[1][2]
+
+ output_scale = _expr.const(inputs[6])
+ output_zero_point = _expr.const(inputs[7])
+
+ assert len(inputs) == 10, "Input quant params not found in op inputs"
+ # These are manually added by add_input_quant_params_to_op_inputs above
+ # In torch, they are retrieved from QTensor data structure at runtime
+ input_scale = _expr.const(inputs[8])
+ input_zero_point = _expr.const(inputs[9])
+
+ strides, padding, dilation = inputs[2], inputs[3], inputs[4]
+ strides = infer_shape(inputs[2])
+ padding = infer_shape(inputs[3])
+ dilation = infer_shape(inputs[4])
+ groups = inputs[5]
+
+ weight_shape = infer_shape(weight)
+ kernel_size = (weight_shape[2], weight_shape[3])
+ out_channels = weight_shape[0]
+
+ if padding[0] != 0 or padding[1] != 0:
+ pad_val = _get_scalar(input_zero_point)
+ inp = _op.nn.pad(inputs[0], pad_width=((0, 0),
+ (0, 0),
+ (padding[0], padding[0]),
+ (padding[1], padding[1])),
+ pad_value=float(pad_val))
+ else:
+ inp = inputs[0]
+
+ # padding is (0, 0) because we did explicit pad op with
+ # pad value being zero point above
+ conv_out = relay.qnn.op.conv2d(inp, weight,
+ input_zero_point, weight_zero_point,
+ input_scale, weight_scale,
+ kernel_size=kernel_size,
+ dilation=dilation, strides=strides,
+ padding=(0, 0), groups=groups,
+ channels=out_channels)
+ bias_var = inputs[1][3]
+
+ return _do_bias_and_requantize(conv_out, bias_var, input_scale,
+ weight_scale, output_scale,
+ output_zero_point, with_relu)
+
+ return _impl
+
+
+def _linear(with_relu=False):
+ # similar to conv
+ def _impl(inputs, _):
+ weight = inputs[1][0]
+ weight_scale = inputs[1][1]
+ weight_zero_point = inputs[1][2]
+ output_scale = _expr.const(inputs[2])
+ output_zero_point = _expr.const(inputs[3])
+ assert len(inputs) == 6, "Input quant params not found in op inputs"
+ # Manually added by add_input_quant_params_to_op_inputs above
+ input_scale = _expr.const(inputs[4])
+ input_zero_point = _expr.const(inputs[5])
+
+ weight_shape = infer_shape(weight)
+ dense = relay.qnn.op.dense(inputs[0], weight,
+ input_zero_point, weight_zero_point,
+ input_scale, weight_scale,
+ units=weight_shape[0])
+ bias_var = inputs[1][3]
+
+ return _do_bias_and_requantize(dense, bias_var, input_scale,
+ weight_scale, output_scale,
+ output_zero_point, with_relu)
+
+ return _impl
+
+
+def _binop(relay_op, with_relu=False):
+ # refer to aten/src/ATen/native/quantized/cpu/{qadd, qmul}.cpp
+ # they piggy backs to fp32 math by dequantize -> fp32 math -> quantize
+ def _impl(inputs, _):
+ output_scale = _expr.const(inputs[2])
+ output_zero_point = _expr.const(inputs[3])
+ assert len(inputs) == 8, "Input quant params not found in op inputs"
+ # Manually added by add_input_quant_params_to_op_inputs above
+ input_scale_lhs = _expr.const(inputs[4])
+ input_zero_point_lhs = _expr.const(inputs[5])
+ input_scale_rhs = _expr.const(inputs[6])
+ input_zero_point_rhs = _expr.const(inputs[7])
+ lhs = inputs[0]
+ rhs = inputs[1]
+
+ if isinstance(lhs, _expr.Call) and lhs.op.name == 'qnn.quantize':
+ lhs = lhs.args[0]
+ else:
+ lhs = relay.qnn.op.dequantize(lhs,
+ input_scale_lhs,
+ input_zero_point_lhs)
+
+ if isinstance(rhs, _expr.Call) and rhs.op.name == 'qnn.quantize':
+ rhs = rhs.args[0]
+ else:
+ rhs = relay.qnn.op.dequantize(rhs,
+ input_scale_rhs,
+ input_zero_point_rhs)
+ fp32_out = relay_op(lhs, rhs)
+
+ if with_relu:
+ fp32_out = _op.nn.relu(fp32_out)
+
+ return relay.qnn.op.quantize(fp32_out,
+ output_scale,
+ output_zero_point,
+ axis=-1,
+ out_dtype="uint8")
+ return _impl
+
+
+def _cat():
+ # refer to aten/src/ATen/native/quantized/cpu/qconcat.cpp
+ # for concat they also piggy backs to fp32(!)
+ # dequantize -> fp32 math -> quantize
+ # we can also use QNN concat op. we observed no change in accuracy
+ def _impl(inputs, _):
+ axis = inputs[1]
+ output_scale = _expr.const(inputs[2])
+ output_zero_point = _expr.const(inputs[3])
+ num_inputs = (len(inputs) - 4) // 2
+ dequantized = []
+
+ for i in range(0, num_inputs):
+ inp_scale = _expr.const(inputs[4+i*2])
+ inp_zp = _expr.const(inputs[4+i*2+1])
+ dequantized.append(relay.qnn.op.dequantize(inputs[0][i],
+ inp_scale, inp_zp))
+
+ concat = _op.tensor.concatenate(dequantized, axis=axis)
+ return relay.qnn.op.quantize(concat, output_scale, output_zero_point,
+ axis=1, out_dtype="uint8")
+
+ return _impl
+
+
+def _add_scalar():
+ # this is used for mobilenet v3
+ def _impl(inputs, _):
+ # refer to aten/src/ATen/native/quantized/cpu/qadd.cpp
+ assert len(inputs) == 6, "Input quant params not found in op inputs"
+ s = inputs[4]
+ z = inputs[5]
+ c = inputs[1]
+ c_q = round(c / s)
+ q_min = 0
+ q_max = 255
+
+ # math for calculating output scale and zp are already done
+ # during _add_output_quant_params_to_scalar_op above
+ out_scale = _expr.const(inputs[2])
+ out_zp = _expr.const(inputs[3])
+
+ if q_min > z - c_q or q_max < z - c_q:
+ dequant = relay.qnn.op.dequantize(inputs[0],
+ _expr.const(s), _expr.const(z))
+ dequantized_add = _op.tensor.add(dequant, _expr.const(c_q * s))
+ return relay.qnn.op.quantize(dequantized_add, out_scale, out_zp,
+ axis=1, out_dtype="uint8")
+ # only scale change
+ return inputs[0]
+
+ return _impl
+
+
+def quantize_scalar(data, scale, zero_point):
+ # used to quantize 6., in mobilenet v3
+ transformed = zero_point + data / scale
+ return max(0, min(round(transformed), 255))
+
+
+def _relu6():
+ # refer to src/ATen/native/quantized/cpu/qrelu.cpp
+ def _impl(inputs, _):
+ assert len(inputs) == 4, "Input quant params not found in op inputs"
+ input_scale = inputs[2]
+ input_zero_point = inputs[3]
+ six = quantize_scalar(6., input_scale, input_zero_point)
+ return _op.tensor.clip(inputs[0], input_zero_point, six)
+ return _impl
+
+
+def _mul_scalar():
+ # this is used for mobilenet v3
+ def _impl(inputs, _):
+ # refer to aten/src/ATen/native/quantized/cpu/qmul.cpp
+ # math for calculating output scale and zp are already done
+ # during _add_output_quant_params_to_scalar_op above
+ assert len(inputs) == 6, "Input quant params not found in op inputs"
+ other_val = inputs[1] # scalar
+
+ if other_val > 0.0:
+ # only scale change
+ return inputs[0]
+ if other_val == 0.0:
+ shape = infer_shape(inputs[0])
+ return _op.full(_expr.const(0), shape, dtype="uint8")
+
+ # negative scale case
+ q_min = 0
+ q_max = 255
+ bias = _expr.const(q_max + q_min, dtype="int8")
+ int8 = bias - _op.cast(inputs[0], "int8")
+ return _op.cast(int8, "uint8")
+
+ return _impl
+
+
+convert_map = {
+ 'aten::quantize_per_tensor': _quantize_per_tensor(),
+ 'quantized::conv2d_relu': _quantized_conv2d(True),
+ 'aten::dequantize': _dequantize(),
+ 'quantized::conv2d': _quantized_conv2d(),
+ 'quantized::add_relu': _binop(relay.add, True),
+ 'quantized::add': _binop(relay.add),
+ 'quantized::mul_relu': _binop(relay.multiply, True),
+ 'quantized::mul': _binop(relay.multiply),
+ 'quantized::linear': _linear(),
+ 'quantized::linear_relu': _linear(True),
+ 'quantized::cat': _cat(),
+ 'quantized::add_scalar': _add_scalar(),
+ 'quantized::mul_scalar': _mul_scalar(),
+ 'quantized::relu6': _relu6()
+}
--- /dev/null
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements. See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership. The ASF licenses this file
+# to you 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
+#
+# http://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.
+""" Tests on quantized torch model conversion """
+import os
+
+from PIL import Image
+
+import numpy as np
+
+import torch
+from torch import nn
+from torch.quantization import QuantStub, DeQuantStub
+from torch.quantization import fuse_modules, QuantWrapper
+
+import tvm
+from tvm import relay
+from tvm.relay.frontend.pytorch import get_graph_input_names
+from tvm.contrib.download import download_testdata
+
+
+def torch_version_check():
+ from packaging import version
+ return version.parse(torch.__version__) > version.parse("1.4.0")
+
+
+def get_tvm_runtime(script_module, input_name, ishape):
+
+ input_shapes = {input_name: ishape}
+ mod, params = relay.frontend.from_pytorch(script_module, input_shapes)
+
+ with relay.build_config(opt_level=3):
+ # test on only cpu for now, torch cannot run quant models on cuda
+ # also not to make CI too slow
+ json, lib, params = relay.build(mod, target="llvm", params=params)
+
+ runtime = tvm.contrib.graph_runtime.create(json, lib, tvm.cpu(0))
+ runtime.set_input(**params)
+ return runtime
+
+
+def get_qconfig(per_channel):
+ from torch.quantization.observer import MovingAverageMinMaxObserver
+ from torch.quantization.observer import default_weight_observer
+
+ if per_channel:
+ return torch.quantization.get_default_qconfig('fbgemm')
+ else:
+ act = MovingAverageMinMaxObserver.with_args(reduce_range=False)
+ return torch.quantization.QConfig(activation=act,
+ weight=default_weight_observer)
+
+
+def quantize_model(model, inp, per_channel=False, dummy=True):
+ model.fuse_model()
+ model.qconfig = get_qconfig(per_channel)
+ torch.quantization.prepare(model, inplace=True)
+ model(inp)
+ torch.quantization.convert(model, inplace=True)
+
+
+class ConvBn(nn.Module):
+ def __init__(self, with_relu=False):
+ super().__init__()
+ layers = [nn.Conv2d(3, 32, 3, bias=True),
+ nn.BatchNorm2d(32)]
+ if with_relu:
+ layers.append(nn.ReLU())
+ self.conv = nn.Sequential(*layers)
+ self.quant_wrap = QuantWrapper(self.conv)
+ self.with_relu = with_relu
+
+ def forward(self, x):
+ return self.quant_wrap(x)
+
+ def fuse_model(self):
+ indices = ["0", "1"]
+ if self.with_relu:
+ indices.append("2")
+ fuse_modules(self.conv, indices, inplace=True)
+
+
+class Linear(nn.Module):
+ def __init__(self, with_relu=False):
+ super().__init__()
+ layers = [nn.Linear(16, 32)]
+ if with_relu:
+ layers.append(nn.ReLU())
+ self.fc = nn.Sequential(*layers)
+ self.quant_wrap = QuantWrapper(self.fc)
+ self.with_relu = with_relu
+
+ def forward(self, x):
+ return self.quant_wrap(x)
+
+ def fuse_model(self):
+ if self.with_relu:
+ fuse_modules(self.fc, ["0", "1"], inplace=True)
+
+
+class ReLU(nn.Module):
+ def __init__(self):
+ super().__init__()
+ self.relu = QuantWrapper(nn.ReLU())
+
+ def forward(self, x):
+ return self.relu(x)
+
+ def fuse_model(self):
+ pass
+
+
+# Mobilenet V3 related modules
+class Hsigmoid(nn.Module):
+ def __init__(self, inplace=True, add_stub=False):
+ super().__init__()
+ self.float_op = nn.quantized.FloatFunctional()
+ self.relu6 = nn.ReLU6(inplace=inplace)
+ self.quant = QuantStub()
+ self.dequant = DeQuantStub()
+ self.add_stub = add_stub
+
+ def forward(self, x):
+ if self.add_stub:
+ x = self.quant(x)
+ relu6 = self.relu6(self.float_op.add_scalar(x, 3.))
+ mul = self.float_op.mul_scalar(relu6, 1/6.)
+ if self.add_stub:
+ mul = self.dequant(mul)
+ return mul
+
+ def fuse_model(self):
+ pass
+
+
+class Hswish(nn.Module):
+ def __init__(self, inplace=True, add_stub=False):
+ super(Hswish, self).__init__()
+ self.float_op = nn.quantized.FloatFunctional()
+ self.hsigmoid = Hsigmoid(inplace, add_stub=False)
+ self.quant = QuantStub()
+ self.dequant = DeQuantStub()
+ self.add_stub = add_stub
+
+ def forward(self, x):
+ if self.add_stub:
+ x = self.quant(x)
+ mul = self.float_op.mul(x, self.hsigmoid(x))
+ if self.add_stub:
+ mul = self.dequant(mul)
+ return mul
+
+ def fuse_model(self):
+ pass
+
+
+class SqueezeExcite(nn.Module):
+ def __init__(self, channel, reduction=4, add_stub=False):
+ super(SqueezeExcite, self).__init__()
+ self.avg_pool = nn.AdaptiveAvgPool2d(1)
+ self.fc = nn.Sequential(
+ nn.Linear(channel, channel // reduction, bias=False),
+ nn.ReLU(inplace=True),
+ nn.Linear(channel // reduction, channel, bias=False),
+ Hsigmoid(add_stub=False)
+ )
+ self.fmul = nn.quantized.FloatFunctional()
+ self.quant = QuantStub()
+ self.dequant = DeQuantStub()
+ self.add_stub = add_stub
+
+ def forward(self, x):
+ b, c, _, _ = x.size()
+ if self.add_stub:
+ x = self.quant(x)
+ y = self.avg_pool(x).view(b, c)
+ y = self.fc(y).view(b, c, 1, 1)
+ out = self.fmul.mul(x, y.expand_as(x))
+ if self.add_stub:
+ return self.dequant(out)
+ else:
+ return out
+
+ def fuse_model(self):
+ fuse_modules(self.fc, ["0", "1"], inplace=True)
+
+
+# test on quantized::mul_scalar with negative scale
+class MulScalarNegative(nn.Module):
+ def __init__(self, ):
+ super().__init__()
+ self.float_op = nn.quantized.FloatFunctional()
+ self.quant = QuantStub()
+ self.dequant = DeQuantStub()
+
+ def forward(self, x):
+ x = self.quant(x)
+ mul = self.float_op.mul_scalar(x, -0.3)
+ return self.dequant(mul)
+
+ def fuse_model(self):
+ pass
+
+
+class UpsamplingBilinear(nn.Module):
+ def __init__(self):
+ super().__init__()
+ self.relu = QuantWrapper(nn.ReLU())
+ self.quant = QuantStub()
+ self.dequant = DeQuantStub()
+
+ def forward(self, x):
+ x = self.quant(x)
+ upsample = nn.functional.interpolate(x, scale_factor=2,
+ mode='bilinear',
+ align_corners=True)
+ return self.dequant(upsample)
+
+ def fuse_model(self):
+ pass
+
+
+def test_quantized_modules():
+ imagenet_ishape = (1, 3, 224, 224)
+
+ qmodules = [
+ ("relu", imagenet_ishape, ReLU(), False),
+ ("upsample bilinear", (1, 3, 64, 64), UpsamplingBilinear(), False),
+ ]
+
+ for per_channel in [False, True]:
+ if per_channel:
+ postfix = ", per_channel"
+ else:
+ postfix = ""
+
+ qmodules += [
+ ("conv_bn" + postfix, imagenet_ishape, ConvBn(), per_channel),
+ ("conv_bn_relu" + postfix, imagenet_ishape, ConvBn(with_relu=True), per_channel),
+ ("linear" + postfix, (16, 16), Linear(), per_channel),
+ ("linear_relu" + postfix, (16, 16), Linear(with_relu=True), per_channel)
+ ]
+
+ if torch_version_check():
+ qmodules += [
+ ("hsigmoid", imagenet_ishape, Hsigmoid(add_stub=True), False),
+ ("hswish", imagenet_ishape, Hswish(add_stub=True), False),
+ ("semodule", (1, 16, 64, 64), SqueezeExcite(16, add_stub=True), False),
+ ("semodule, per_channel", (1, 16, 64, 64), SqueezeExcite(16, add_stub=True), True),
+ ("mul_scalar negative", imagenet_ishape, MulScalarNegative(), False)
+ ]
+ else:
+ print("Skipping tests that require torch > 1.4")
+
+ for (module_name, ishape, raw_module, per_channel) in qmodules:
+ raw_module.eval()
+ inp = torch.rand(ishape)
+
+ quantize_model(raw_module, inp, per_channel=per_channel, dummy=True)
+ script_module = torch.jit.trace(raw_module, inp).eval()
+
+ with torch.no_grad():
+ pt_result = script_module(inp.clone()).numpy()
+
+ input_name = get_graph_input_names(script_module)[0]
+
+ runtime = get_tvm_runtime(script_module, input_name, ishape)
+ runtime.set_input(input_name, inp.numpy().copy())
+ runtime.run()
+ tvm_result = runtime.get_output(0).asnumpy()
+
+ max_abs_diff = np.max(np.abs(tvm_result - pt_result))
+ mean_abs_diff = np.mean(np.abs(tvm_result - pt_result))
+ num_identical = np.sum(tvm_result == pt_result)
+ match_ratio = num_identical / float(np.prod(tvm_result.shape))
+
+ print(module_name, max_abs_diff, mean_abs_diff, match_ratio)
+
+ # sample outputs
+ """
+ relu 0.0039215684 2.6052087e-08 0.9999933567176871
+ upsample bilinear 0.0 0.0 1.0
+ conv_bn 0.22062653 0.011478779 0.6909348115006899
+ conv_bn_relu 0.3700896 0.010921672 0.7489366477964451
+ linear 0.15987062 0.009231662 0.794921875
+ linear_relu 0.14180502 0.0053220326 0.8828125
+ conv_bn, per_channel 0.01654929 2.9486866e-06 0.9998218235127019
+ conv_bn_relu, per_channel 0.009089053 1.4926576e-06 0.9998357732732732
+ linear, per_channel 0.0 0.0 1.0
+ linear_relu, per_channel 0.0 0.0 1.0
+ hsigmoid 0.002614379 0.00020525524 0.9214896896258503
+ hswish 0.0052286386 0.00063522335 0.7587359162414966
+ semodule, per_channel 0.0039885044 0.0008620687 0.7838592529296875
+ mul_scalar negative 0.0011764616 7.815566e-09 0.9999933567176871
+ """
+
+ # we cannot make any guarantee on how close the raw output is to torch
+ # tvm.testing.assert_allclose(tvm_result, pt_result, rtol=1e-1, atol=1e-1)
+
+
+def test_quantized_imagenet():
+ def get_transform():
+ import torchvision.transforms as transforms
+ normalize = transforms.Normalize(mean=[0.485, 0.456, 0.406],
+ std=[0.229, 0.224, 0.225])
+ return transforms.Compose([
+ transforms.Resize(256),
+ transforms.CenterCrop(224),
+ transforms.ToTensor(),
+ normalize,
+ ])
+
+ def get_real_image(im_height, im_width):
+ repo_base = 'https://github.com/dmlc/web-data/raw/master/tensorflow/models/InceptionV1/'
+ img_name = 'elephant-299.jpg'
+ image_url = os.path.join(repo_base, img_name)
+ img_path = download_testdata(image_url, img_name, module='data')
+ return Image.open(img_path).resize((im_height, im_width))
+
+ def get_imagenet_input():
+ im = get_real_image(224, 224)
+ preprocess = get_transform()
+ pt_tensor = preprocess(im)
+ return np.expand_dims(pt_tensor.numpy(), 0)
+
+ from torchvision.models.quantization import resnet as qresnet
+ from torchvision.models.quantization import mobilenet as qmobilenet
+ from torchvision.models.quantization import inception as qinception
+ from torchvision.models.quantization import googlenet as qgooglenet
+
+ qmodels = []
+
+ for per_channel in [False, True]:
+ qmodels += [
+ ("resnet18", qresnet.resnet18(pretrained=True), per_channel),
+ ("mobilenet_v2", qmobilenet.mobilenet_v2(pretrained=True), per_channel),
+ ("inception_v3", qinception.inception_v3(pretrained=True), per_channel),
+ ("googlenet", qgooglenet(pretrained=True), per_channel),
+ ]
+
+ results = []
+
+ for (model_name, raw_model, per_channel) in qmodels:
+ raw_model.eval()
+
+ if per_channel:
+ model_name += ", per channel quantization"
+ else:
+ model_name += ", per tensor quantization"
+
+ inp = get_imagenet_input()
+ pt_inp = torch.from_numpy(inp)
+
+ quantize_model(raw_model, pt_inp, per_channel=per_channel, dummy=False)
+ script_module = torch.jit.trace(raw_model, pt_inp).eval()
+
+ with torch.no_grad():
+ pt_result = script_module(pt_inp).numpy()
+
+ input_name = get_graph_input_names(script_module)[0]
+ runtime = get_tvm_runtime(script_module, input_name, (1, 3, 224, 224))
+ runtime.set_input(input_name, inp)
+ runtime.run()
+
+ tvm_result = runtime.get_output(0).asnumpy()
+
+ results.append((model_name, pt_result[0], tvm_result[0]))
+
+ for (model_name, pt_result, tvm_result) in results:
+ max_abs_diff = np.max(np.abs(tvm_result - pt_result))
+ mean_abs_diff = np.mean(np.abs(tvm_result - pt_result))
+ num_identical = np.sum(tvm_result == pt_result)
+ pt_top3_labels = np.argsort(pt_result)[::-1][:3]
+ tvm_top3_labels = np.argsort(pt_result)[::-1][:3]
+
+ print("\nModel name: %s" % model_name)
+ print("PyTorch top3 label:", pt_top3_labels)
+ print("TVM top3 label:", tvm_top3_labels)
+ print("max abs diff:", max_abs_diff)
+ print("mean abs_diff:", mean_abs_diff)
+ print("%d in 1000 raw outputs identical." % num_identical)
+
+ assert set(pt_top3_labels) == set(tvm_top3_labels)
+
+ # sample outputs
+ """
+ Model name: resnet18, per tensor quantization
+ PyTorch top3 label: [386 101 385]
+ TVM top3 label: [386 101 385]
+ max abs diff: 0.65681696
+ mean abs_diff: 0.14055882
+ 236 in 1000 raw outputs identical.
+
+ Model name: mobilenet_v2, per tensor quantization
+ PyTorch top3 label: [101 386 385]
+ TVM top3 label: [101 386 385]
+ max abs diff: 2.1262953
+ mean abs_diff: 0.41025686
+ 101 in 1000 raw outputs identical.
+
+ Model name: inception_v3, per tensor quantization
+ PyTorch top3 label: [101 386 385]
+ TVM top3 label: [101 386 385]
+ max abs diff: 0.9994669
+ mean abs_diff: 0.098697364
+ 272 in 1000 raw outputs identical.
+
+ Model name: googlenet, per tensor quantization
+ PyTorch top3 label: [101 386 385]
+ TVM top3 label: [101 386 385]
+ max abs diff: 0.28248847
+ mean abs_diff: 0.0634469
+ 274 in 1000 raw outputs identical.
+
+ Model name: resnet18, per channel quantization
+ PyTorch top3 label: [101 386 385]
+ TVM top3 label: [101 386 385]
+ max abs diff: 0.65908074
+ mean abs_diff: 0.1274223
+ 469 in 1000 raw outputs identical.
+
+ Model name: mobilenet_v2, per channel quantization
+ PyTorch top3 label: [101 386 385]
+ TVM top3 label: [101 386 385]
+ max abs diff: 0.71120834
+ mean abs_diff: 0.15883648
+ 423 in 1000 raw outputs identical.
+
+ Model name: inception_v3, per channel quantization
+ PyTorch top3 label: [386 101 385]
+ TVM top3 label: [386 101 385]
+ max abs diff: 1.3372154
+ mean abs_diff: 0.1225224
+ 401 in 1000 raw outputs identical.
+
+ Model name: googlenet, per channel quantization
+ PyTorch top3 label: [101 386 385]
+ TVM top3 label: [101 386 385]
+ max abs diff: 0.34015465
+ mean abs_diff: 0.054197952
+ 558 in 1000 raw outputs identical.
+ """