onnxruntime/onnxruntime/python/tools/transformers/fusion_gpt_attention.py
Tianlei Wu 1f304fbee7
Attention with past and no unidirectional mask (#5557)
* Update fusions to support shared node, and mask of all ones
2020-10-21 20:12:02 -07:00

243 lines
12 KiB
Python

#-------------------------------------------------------------------------
# Copyright (c) Microsoft Corporation. All rights reserved.
# Licensed under the MIT License.
#--------------------------------------------------------------------------
import numpy as np
from logging import getLogger
from onnx import helper, numpy_helper, TensorProto
from onnx_model import OnnxModel
from fusion_base import Fusion
from fusion_utils import FusionUtils
logger = getLogger(__name__)
class FusionGptAttention(Fusion):
"""
Fuse GPT-2 Attention with past state subgraph into one Attention node.
This does not support attention_mask graph input right now.
"""
def __init__(self, model: OnnxModel, num_heads: int):
super().__init__(model, "Attention", "LayerNormalization", "with past")
self.num_heads = num_heads
self.utils = FusionUtils(model)
self.casted_attention_mask = {} # map from name of attention mask to the name that casted to int32
def create_attention_node(self, gemm, gemm_qkv, past, present, input, output, mask, is_unidirectional):
attention_node_name = self.model.create_node_name('GptAttention')
attention_node = helper.make_node('Attention',
inputs=[input, gemm.input[1], gemm.input[2], mask, past],
outputs=[attention_node_name + "_output", present],
name=attention_node_name)
attention_node.domain = "com.microsoft"
attention_node.attribute.extend([
helper.make_attribute("num_heads", self.num_heads),
helper.make_attribute("unidirectional", 1 if is_unidirectional else 0)
])
matmul_node = helper.make_node('MatMul',
inputs=[attention_node_name + "_output", gemm_qkv.input[1]],
outputs=[attention_node_name + "_matmul_output"],
name=attention_node_name + "_matmul")
add_node = helper.make_node('Add',
inputs=[attention_node_name + "_matmul_output", gemm_qkv.input[2]],
outputs=[output],
name=attention_node_name + "_add")
self.nodes_to_add.extend([attention_node, matmul_node, add_node])
def fuse(self, normalize_node, input_name_to_nodes, output_name_to_node):
past = None
present = None
return_indice = []
qkv_nodes = self.model.match_parent_path(
normalize_node,
['Add', 'Reshape', 'Gemm', 'Reshape', 'Reshape', 'Transpose', 'MatMul'],
[0, None, 0, 0, 0, 0, 0],
output_name_to_node=output_name_to_node,
return_indice=return_indice
) # yapf: disable
if qkv_nodes is None:
return
(add_qkv, reshape_qkv, gemm_qkv, reshape_1, reshape_2, transpose_qkv, matmul_qkv) = qkv_nodes
another_input = add_qkv.input[1 - return_indice[0]]
v_nodes = self.model.match_parent_path(
matmul_qkv,
['Concat', 'Transpose', 'Reshape', 'Split', 'Reshape', 'Gemm', 'Reshape'],
[1, 1, 0, 0, 0, 0, 0]) # yapf: disable
if v_nodes is None:
logger.debug("fuse_attention: failed to match v path")
return
(concat_v, transpose_v, reshape_v, split_v, reshape_after_gemm, gemm, reshape_before_gemm) = v_nodes
# concat <-- Gather(indices=1) <-- past
# |
# unsqueeze
# |
# concat --> present
gather_v = self.model.get_parent(concat_v, 0, output_name_to_node)
if gather_v.op_type != 'Gather':
logger.info("expect Gather for past")
return
if not self.model.find_constant_input(gather_v, 1) == 1:
logger.info("expect indices=1 for Gather of past")
return
past = gather_v.input[0]
if not self.model.find_graph_input(past):
logger.info("expect past to be graph input")
return
unsqueeze_present_v = self.model.find_first_child_by_type(concat_v,
'Unsqueeze',
input_name_to_nodes,
recursive=False)
if not unsqueeze_present_v:
logger.info("expect unsqueeze for present")
return
concat_present = self.model.find_first_child_by_type(unsqueeze_present_v,
'Concat',
input_name_to_nodes,
recursive=False)
if not concat_present:
logger.info("expect concat for present")
return
present = concat_present.output[0]
if not self.model.find_graph_output(present):
logger.info("expect present to be graph input")
return
layernorm_before_attention = self.model.get_parent(reshape_before_gemm, 0, output_name_to_node)
if layernorm_before_attention is None or layernorm_before_attention.op_type != 'LayerNormalization':
logger.debug(f"failed to get layernorm before gemm. Got {layernorm_before_attention.op_type}")
return
if not another_input in layernorm_before_attention.input:
logger.debug("Add and LayerNormalization shall have one same input")
return
is_unidirectional = True
slice_mask = None
input_mask_nodes = None
qk_nodes = self.model.match_parent_path(matmul_qkv, ['Softmax', 'Sub', 'Mul', 'Div', 'MatMul'], [0, 0, 0, 0, 0])
if qk_nodes is not None:
(softmax_qk, sub_qk, mul_qk, div_qk, matmul_qk) = qk_nodes
mask_nodes = self.model.match_parent_path(
sub_qk,
['Mul', 'Sub', 'Slice', 'Slice', 'Unsqueeze', 'Sub', 'Squeeze', 'Slice', 'Shape', 'Div'],
[1, 0, 1, 0, 1, 0, 0, 0, 0, 0]) # yapf: disable
if mask_nodes is None:
logger.debug("fuse_attention: failed to match unidirectional mask path")
return
div_mask = mask_nodes[-1]
slice_mask = mask_nodes[3]
if div_qk != div_mask:
logger.debug("fuse_attention: skip since div_qk != div_mask")
return
else:
# New pattern for gpt2 from PyTorch 1.5.0 and Transformers 2.9.0.
i, qk_nodes, _ = self.model.match_parent_paths(
matmul_qkv, [(['Softmax', 'Where', 'Div', 'MatMul'], [0, 0, 1, 0]),
(['Softmax', 'Add', 'Where', 'Div', 'MatMul'], [0, 0, 0, 1, 0])], output_name_to_node)
if qk_nodes is None:
logger.debug("fuse_attention: failed to match qk nodes")
return
where_qk = qk_nodes[-3]
div_qk = qk_nodes[-2]
matmul_qk = qk_nodes[-1]
if i == 1:
add_qk = qk_nodes[1]
_, input_mask_nodes, _ = self.model.match_parent_paths(
add_qk, [(['Mul', 'Sub', 'Cast', 'Unsqueeze', 'Unsqueeze', 'Reshape'], [1, 0, 1, 0, 0, 0]),
(['Mul', 'Sub', 'Unsqueeze', 'Unsqueeze', 'Reshape'], [1, 0, 1, 0, 0])],
output_name_to_node)
if input_mask_nodes is None:
logger.debug("fuse_attention: failed to match input attention mask path")
return
mask_nodes = self.model.match_parent_path(
where_qk,
['Cast', 'Slice', 'Slice', 'Unsqueeze', 'Sub', 'Squeeze', 'Slice', 'Shape', 'Div'],
[ 0, 0, 0, 1, 0, 0, 0, 0, 0]) # yapf: disable
if mask_nodes is None:
logger.debug("fuse_attention: failed to match mask path")
return
div_mask = mask_nodes[-1]
slice_mask = mask_nodes[2]
if div_qk != div_mask:
logger.debug("fuse_attention: skip since div_qk != div_mask")
return
# Validate that the mask data is either lower triangular (unidirectional) or all ones
mask_data = numpy_helper.to_array(self.model.get_initializer(slice_mask.input[0]))
if not (len(mask_data.shape) == 4 and mask_data.shape[:2] == (1, 1)
and mask_data.shape[2] == mask_data.shape[3]):
logger.debug("fuse_attention: skip since mask shape is not 1x1xWxW")
return
if np.allclose(mask_data, np.ones_like(mask_data)):
is_unidirectional = False
elif not np.allclose(mask_data, np.tril(np.ones_like(mask_data))):
logger.debug("fuse_attention: skip since mask is neither lower triangular nor ones")
return
q_nodes = self.model.match_parent_path(matmul_qk, ['Transpose', 'Reshape', 'Split'], [0, 0, 0])
if q_nodes is None:
logger.debug("fuse_attention: failed to match q path")
return
(transpose_q, reshape_q, split_q) = q_nodes
if split_v != split_q:
logger.debug("fuse_attention: skip since split_v != split_q")
return
k_nodes = self.model.match_parent_path(matmul_qk, ['Concat', 'Transpose', 'Reshape', 'Split'], [1, 1, 0, 0])
if k_nodes is None:
logger.debug("fuse_attention: failed to match k path")
return
(concat_k, transpose_k, reshape_k, split_k) = k_nodes
if split_v != split_k:
logger.debug("fuse_attention: skip since split_v != split_k")
return
# concat_k <-- Transpose (perm=0,1,3,2) <-- Gather(axes=0, indices=0) <-- past
# |
# Transpose (perm=0,1,3,2)
# |
# unsqueeze
# |
# concat --> present
past_k_nodes = self.model.match_parent_path(concat_k, ['Transpose', 'Gather'], [0, 0])
if past_k_nodes is None:
logger.debug("fuse_attention: failed to match past_k_nodes path")
return
gather_past_k = past_k_nodes[-1]
if not self.model.find_constant_input(gather_past_k, 0) == 1:
logger.info("expect indices=0 for Gather k of past")
return
past_k = gather_past_k.input[0]
if past != past_k:
logger.info("expect past to be same")
return
attention_mask_input_name = ''
if input_mask_nodes is not None:
input_name = input_mask_nodes[-1].input[0]
if input_name in self.casted_attention_mask:
attention_mask_input_name = self.casted_attention_mask[input_name]
elif self.model.find_graph_input(input_name):
casted, attention_mask_input_name = self.utils.cast_graph_input_to_int32(input_name)
self.casted_attention_mask[input_name] = attention_mask_input_name
else:
attention_mask_input_name, cast_node = self.utils.cast_input_to_int32(input_name)
self.casted_attention_mask[input_name] = attention_mask_input_name
self.create_attention_node(gemm, gemm_qkv, past, present, layernorm_before_attention.output[0],
reshape_qkv.output[0], attention_mask_input_name, is_unidirectional)
# we rely on prune_graph() to clean old subgraph nodes:
# qk_nodes + q_nodes + k_nodes + v_nodes + mask_nodes + [reshape_qkv, transpose_qkv, matmul_qkv]
self.prune_graph = True