* flax gpt2

* combine masks

* handle shared embeds

* add causal LM sample

* style

* add tests

* style

* fix imports, docs, quality

* don't use cache

* add cache

* add cache 1st version

* make use cache work

* start adding test for generation

* finish generation loop compilation

* rewrite test

* finish

* update

* update

* apply sylvains suggestions

* update

* refactor

* fix typo

Co-authored-by: Patrick von Platen <patrick.v.platen@gmail.com>
This commit is contained in:
Suraj Patil 2021-05-19 03:20:51 +05:30 committed by GitHub
parent eb3e072a3b
commit ca33278fdb
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13 changed files with 1106 additions and 12 deletions

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@ -355,7 +355,7 @@ Flax), PyTorch, and/or TensorFlow.
+-----------------------------+----------------+----------------+-----------------+--------------------+--------------+
| OpenAI GPT | ✅ | ✅ | ✅ | ✅ | ❌ |
+-----------------------------+----------------+----------------+-----------------+--------------------+--------------+
| OpenAI GPT-2 | ✅ | ✅ | ✅ | ✅ | |
| OpenAI GPT-2 | ✅ | ✅ | ✅ | ✅ | |
+-----------------------------+----------------+----------------+-----------------+--------------------+--------------+
| Pegasus | ✅ | ✅ | ✅ | ✅ | ❌ |
+-----------------------------+----------------+----------------+-----------------+--------------------+--------------+

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@ -205,6 +205,13 @@ FlaxAutoModel
:members:
FlaxAutoModelForCausalLM
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.. autoclass:: transformers.FlaxAutoModelForCausalLM
:members:
FlaxAutoModelForPreTraining
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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@ -139,3 +139,17 @@ TFSequenceClassifierOutputWithPast
.. autoclass:: transformers.modeling_tf_outputs.TFSequenceClassifierOutputWithPast
:members:
FlaxGPT2Model
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.. autoclass:: transformers.FlaxGPT2Model
:members: __call__
FlaxGPT2LMHeadModel
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.. autoclass:: transformers.FlaxGPT2LMHeadModel
:members: __call__

View File

@ -1409,6 +1409,7 @@ if is_flax_available():
_import_structure["modeling_flax_utils"] = ["FlaxPreTrainedModel"]
_import_structure["models.auto"].extend(
[
"FLAX_MODEL_FOR_CAUSAL_LM_MAPPING",
"FLAX_MODEL_FOR_MASKED_LM_MAPPING",
"FLAX_MODEL_FOR_MULTIPLE_CHOICE_MAPPING",
"FLAX_MODEL_FOR_NEXT_SENTENCE_PREDICTION_MAPPING",
@ -1418,6 +1419,7 @@ if is_flax_available():
"FLAX_MODEL_FOR_TOKEN_CLASSIFICATION_MAPPING",
"FLAX_MODEL_MAPPING",
"FlaxAutoModel",
"FlaxAutoModelForCausalLM",
"FlaxAutoModelForMaskedLM",
"FlaxAutoModelForMultipleChoice",
"FlaxAutoModelForNextSentencePrediction",
@ -1452,6 +1454,7 @@ if is_flax_available():
"FlaxElectraPreTrainedModel",
]
)
_import_structure["models.gpt2"].extend(["FlaxGPT2LMHeadModel", "FlaxGPT2Model"])
_import_structure["models.roberta"].extend(
[
"FlaxRobertaForMaskedLM",
@ -2634,6 +2637,7 @@ if TYPE_CHECKING:
if is_flax_available():
from .modeling_flax_utils import FlaxPreTrainedModel
from .models.auto import (
FLAX_MODEL_FOR_CAUSAL_LM_MAPPING,
FLAX_MODEL_FOR_MASKED_LM_MAPPING,
FLAX_MODEL_FOR_MULTIPLE_CHOICE_MAPPING,
FLAX_MODEL_FOR_NEXT_SENTENCE_PREDICTION_MAPPING,
@ -2643,6 +2647,7 @@ if TYPE_CHECKING:
FLAX_MODEL_FOR_TOKEN_CLASSIFICATION_MAPPING,
FLAX_MODEL_MAPPING,
FlaxAutoModel,
FlaxAutoModelForCausalLM,
FlaxAutoModelForMaskedLM,
FlaxAutoModelForMultipleChoice,
FlaxAutoModelForNextSentencePrediction,
@ -2672,6 +2677,7 @@ if TYPE_CHECKING:
FlaxElectraModel,
FlaxElectraPreTrainedModel,
)
from .models.gpt2 import FlaxGPT2LMHeadModel, FlaxGPT2Model
from .models.roberta import (
FlaxRobertaForMaskedLM,
FlaxRobertaForMultipleChoice,

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@ -1038,6 +1038,20 @@ FLAX_MULTIPLE_CHOICE_SAMPLE = r"""
>>> logits = outputs.logits
"""
FLAX_CAUSAL_LM_SAMPLE = r"""
Example::
>>> from transformers import {tokenizer_class}, {model_class}
>>> tokenizer = {tokenizer_class}.from_pretrained('{checkpoint}')
>>> model = {model_class}.from_pretrained('{checkpoint}')
>>> inputs = tokenizer("Hello, my dog is cute", return_tensors="jax")
>>> outputs = model(**inputs, labels=inputs["input_ids"])
>>> logits = outputs.logits
"""
FLAX_SAMPLE_DOCSTRINGS = {
"SequenceClassification": FLAX_SEQUENCE_CLASSIFICATION_SAMPLE,
"QuestionAnswering": FLAX_QUESTION_ANSWERING_SAMPLE,
@ -1045,6 +1059,7 @@ FLAX_SAMPLE_DOCSTRINGS = {
"MultipleChoice": FLAX_MULTIPLE_CHOICE_SAMPLE,
"MaskedLM": FLAX_MASKED_LM_SAMPLE,
"BaseModel": FLAX_BASE_MODEL_SAMPLE,
"LMHead": FLAX_CAUSAL_LM_SAMPLE,
}

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@ -13,7 +13,7 @@
# limitations under the License.
from dataclasses import dataclass
from typing import Optional, Tuple
from typing import Dict, Optional, Tuple
import jaxlib.xla_extension as jax_xla
@ -46,6 +46,36 @@ class FlaxBaseModelOutput(ModelOutput):
attentions: Optional[Tuple[jax_xla.DeviceArray]] = None
@dataclass
class FlaxBaseModelOutputWithPast(ModelOutput):
"""
Base class for model's outputs, with potential hidden states and attentions.
Args:
last_hidden_state (:obj:`jax_xla.DeviceArray` of shape :obj:`(batch_size, sequence_length, hidden_size)`):
Sequence of hidden-states at the output of the last layer of the model.
past_key_values (:obj:`Dict[str, jax_xla.DeviceArray]`):
Dictionary of pre-computed hidden-states (key and values in the attention blocks) that can be used for fast
auto-regressive decoding. Pre-computed key and value hidden-states are of shape `[batch_size, max_length]`.
hidden_states (:obj:`tuple(jax_xla.DeviceArray)`, `optional`, returned when ``output_hidden_states=True`` is passed or when ``config.output_hidden_states=True``):
Tuple of :obj:`jax_xla.DeviceArray` (one for the output of the embeddings + one for the output of each
layer) of shape :obj:`(batch_size, sequence_length, hidden_size)`.
Hidden-states of the model at the output of each layer plus the initial embedding outputs.
attentions (:obj:`tuple(jax_xla.DeviceArray)`, `optional`, returned when ``output_attentions=True`` is passed or when ``config.output_attentions=True``):
Tuple of :obj:`jax_xla.DeviceArray` (one for each layer) of shape :obj:`(batch_size, num_heads,
sequence_length, sequence_length)`.
Attentions weights after the attention softmax, used to compute the weighted average in the self-attention
heads.
"""
last_hidden_state: jax_xla.DeviceArray = None
past_key_values: Optional[Dict[str, jax_xla.DeviceArray]] = None
hidden_states: Optional[Tuple[jax_xla.DeviceArray]] = None
attentions: Optional[Tuple[jax_xla.DeviceArray]] = None
@dataclass
class FlaxBaseModelOutputWithPooling(ModelOutput):
"""
@ -103,6 +133,9 @@ class FlaxMaskedLMOutput(ModelOutput):
attentions: Optional[Tuple[jax_xla.DeviceArray]] = None
FlaxCausalLMOutput = FlaxMaskedLMOutput
@dataclass
class FlaxNextSentencePredictorOutput(ModelOutput):
"""

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@ -85,6 +85,7 @@ if is_tf_available():
if is_flax_available():
_import_structure["modeling_flax_auto"] = [
"FLAX_MODEL_FOR_CAUSAL_LM_MAPPING",
"FLAX_MODEL_FOR_MASKED_LM_MAPPING",
"FLAX_MODEL_FOR_MULTIPLE_CHOICE_MAPPING",
"FLAX_MODEL_FOR_NEXT_SENTENCE_PREDICTION_MAPPING",
@ -94,6 +95,7 @@ if is_flax_available():
"FLAX_MODEL_FOR_TOKEN_CLASSIFICATION_MAPPING",
"FLAX_MODEL_MAPPING",
"FlaxAutoModel",
"FlaxAutoModelForCausalLM",
"FlaxAutoModelForMaskedLM",
"FlaxAutoModelForMultipleChoice",
"FlaxAutoModelForNextSentencePrediction",
@ -167,6 +169,7 @@ if TYPE_CHECKING:
if is_flax_available():
from .modeling_flax_auto import (
FLAX_MODEL_FOR_CAUSAL_LM_MAPPING,
FLAX_MODEL_FOR_MASKED_LM_MAPPING,
FLAX_MODEL_FOR_MULTIPLE_CHOICE_MAPPING,
FLAX_MODEL_FOR_NEXT_SENTENCE_PREDICTION_MAPPING,
@ -176,6 +179,7 @@ if TYPE_CHECKING:
FLAX_MODEL_FOR_TOKEN_CLASSIFICATION_MAPPING,
FLAX_MODEL_MAPPING,
FlaxAutoModel,
FlaxAutoModelForCausalLM,
FlaxAutoModelForMaskedLM,
FlaxAutoModelForMultipleChoice,
FlaxAutoModelForNextSentencePrediction,

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@ -37,6 +37,7 @@ from ..electra.modeling_flax_electra import (
FlaxElectraForTokenClassification,
FlaxElectraModel,
)
from ..gpt2.modeling_flax_gpt2 import FlaxGPT2LMHeadModel, FlaxGPT2Model
from ..roberta.modeling_flax_roberta import (
FlaxRobertaForMaskedLM,
FlaxRobertaForMultipleChoice,
@ -46,7 +47,7 @@ from ..roberta.modeling_flax_roberta import (
FlaxRobertaModel,
)
from .auto_factory import auto_class_factory
from .configuration_auto import BertConfig, ElectraConfig, RobertaConfig
from .configuration_auto import BertConfig, ElectraConfig, GPT2Config, RobertaConfig
logger = logging.get_logger(__name__)
@ -57,6 +58,7 @@ FLAX_MODEL_MAPPING = OrderedDict(
# Base model mapping
(RobertaConfig, FlaxRobertaModel),
(BertConfig, FlaxBertModel),
(GPT2Config, FlaxGPT2Model),
(ElectraConfig, FlaxElectraModel),
]
)
@ -79,6 +81,13 @@ FLAX_MODEL_FOR_MASKED_LM_MAPPING = OrderedDict(
]
)
FLAX_MODEL_FOR_CAUSAL_LM_MAPPING = OrderedDict(
[
# Model for Causal LM mapping
(GPT2Config, FlaxGPT2LMHeadModel)
]
)
FLAX_MODEL_FOR_SEQUENCE_CLASSIFICATION_MAPPING = OrderedDict(
[
# Model for Sequence Classification mapping
@ -123,6 +132,10 @@ FLAX_MODEL_FOR_NEXT_SENTENCE_PREDICTION_MAPPING = OrderedDict(
FlaxAutoModel = auto_class_factory("FlaxAutoModel", FLAX_MODEL_MAPPING)
FlaxAutoModelForCausalLM = auto_class_factory(
"FlaxAutoModelForCausalLM", FLAX_MODEL_FOR_CAUSAL_LM_MAPPING, head_doc="causal language modeling"
)
FlaxAutoModelForPreTraining = auto_class_factory(
"FlaxAutoModelForPreTraining", FLAX_MODEL_FOR_PRETRAINING_MAPPING, head_doc="pretraining"
)

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@ -18,7 +18,13 @@
from typing import TYPE_CHECKING
from ...file_utils import _BaseLazyModule, is_tf_available, is_tokenizers_available, is_torch_available
from ...file_utils import (
_BaseLazyModule,
is_flax_available,
is_tf_available,
is_tokenizers_available,
is_torch_available,
)
_import_structure = {
@ -51,6 +57,8 @@ if is_tf_available():
"TFGPT2PreTrainedModel",
]
if is_flax_available():
_import_structure["modeling_flax_gpt2"] = ["FlaxGPT2LMHeadModel", "FlaxGPT2Model"]
if TYPE_CHECKING:
from .configuration_gpt2 import GPT2_PRETRAINED_CONFIG_ARCHIVE_MAP, GPT2Config
@ -81,6 +89,9 @@ if TYPE_CHECKING:
TFGPT2PreTrainedModel,
)
if is_flax_available():
from .modeling_flax_gpt2 import FlaxGPT2LMHeadModel, FlaxGPT2Model
else:
import importlib
import os

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@ -0,0 +1,633 @@
# coding=utf-8
# Copyright 2021 The Google Flax Team Authors and The HuggingFace Inc. team.
#
# 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
#
# 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.
from typing import Any, Optional, Tuple
import flax.linen as nn
import jax
import jax.numpy as jnp
from flax.core.frozen_dict import FrozenDict, unfreeze
from flax.linen import combine_masks, dot_product_attention, make_causal_mask
from flax.traverse_util import flatten_dict
from jax import lax
from ...file_utils import add_start_docstrings, add_start_docstrings_to_model_forward
from ...modeling_flax_outputs import FlaxBaseModelOutput, FlaxBaseModelOutputWithPast, FlaxCausalLMOutput
from ...modeling_flax_utils import ACT2FN, FlaxPreTrainedModel, append_call_sample_docstring
from ...utils import logging
from .configuration_gpt2 import GPT2Config
logger = logging.get_logger(__name__)
_CHECKPOINT_FOR_DOC = "gpt2"
_CONFIG_FOR_DOC = "GPT2Config"
_TOKENIZER_FOR_DOC = "GPT2Tokenizer"
GPT2_START_DOCSTRING = r"""
This model inherits from :class:`~transformers.FlaxPreTrainedModel`. Check the superclass documentation for the
generic methods the library implements for all its model (such as downloading or saving, resizing the input
embeddings, pruning heads etc.)
This model is also a Flax Linen `flax.nn.Module
<https://flax.readthedocs.io/en/latest/_autosummary/flax.nn.module.html>`__ subclass. Use it as a regular Flax
Module and refer to the Flax documentation for all matter related to general usage and behavior.
Finally, this model supports inherent JAX features such as:
- `Just-In-Time (JIT) compilation <https://jax.readthedocs.io/en/latest/jax.html#just-in-time-compilation-jit>`__
- `Automatic Differentiation <https://jax.readthedocs.io/en/latest/jax.html#automatic-differentiation>`__
- `Vectorization <https://jax.readthedocs.io/en/latest/jax.html#vectorization-vmap>`__
- `Parallelization <https://jax.readthedocs.io/en/latest/jax.html#parallelization-pmap>`__
Parameters:
config (:class:`~transformers.GPT2Config`): Model configuration class with all the parameters of the model.
Initializing with a config file does not load the weights associated with the model, only the
configuration. Check out the :meth:`~transformers.FlaxPreTrainedModel.from_pretrained` method to load the
model weights.
"""
GPT2_INPUTS_DOCSTRING = r"""
Args:
input_ids (:obj:`numpy.ndarray` of shape :obj:`(batch_size, input_ids_length)`):
:obj:`input_ids_length` = ``sequence_length``. Indices of input sequence tokens in the vocabulary.
Indices can be obtained using :class:`~transformers.GPT2Tokenizer`. See
:meth:`transformers.PreTrainedTokenizer.encode` and :meth:`transformers.PreTrainedTokenizer.__call__` for
details.
`What are input IDs? <../glossary.html#input-ids>`__
attention_mask (:obj:`numpy.ndarray` of shape :obj:`(batch_size, sequence_length)`, `optional`):
Mask to avoid performing attention on padding token indices. Mask values selected in ``[0, 1]``:
- 1 for tokens that are **not masked**,
- 0 for tokens that are **masked**.
`What are attention masks? <../glossary.html#attention-mask>`__
position_ids (:obj:`numpy.ndarray` of shape :obj:`(batch_size, sequence_length)`, `optional`):
Indices of positions of each input sequence tokens in the position embeddings. Selected in the range ``[0,
config.max_position_embeddings - 1]``.
past_key_values (:obj:`Dict[str, np.ndarray]`, `optional`, returned by ``init_cache`` or when passing previous ``past_key_values``):
Dictionary of pre-computed hidden-states (key and values in the attention blocks) that can be used for fast
auto-regressive decoding. Pre-computed key and value hidden-states are of shape `[batch_size, max_length]`.
output_attentions (:obj:`bool`, `optional`):
Whether or not to return the attentions tensors of all attention layers. See ``attentions`` under returned
tensors for more detail.
output_hidden_states (:obj:`bool`, `optional`):
Whether or not to return the hidden states of all layers. See ``hidden_states`` under returned tensors for
more detail.
return_dict (:obj:`bool`, `optional`):
Whether or not to return a :class:`~transformers.file_utils.ModelOutput` instead of a plain tuple.
"""
class FlaxConv1D(nn.Module):
features: int
use_bias: bool = True
dtype: Any = jnp.float32
precision: Any = None
@nn.compact
def __call__(self, inputs):
inputs = jnp.asarray(inputs, self.dtype)
kernel = self.param("kernel", jax.nn.initializers.normal(stddev=0.02), (self.features, inputs.shape[-1]))
kernel = jnp.asarray(kernel.transpose(), self.dtype)
y = lax.dot_general(inputs, kernel, (((inputs.ndim - 1,), (0,)), ((), ())), precision=self.precision)
if self.use_bias:
bias = self.param("bias", jax.nn.initializers.zeros, (self.features,))
bias = jnp.asarray(bias, self.dtype)
y = y + bias
return y
class FlaxGPT2Attention(nn.Module):
config: GPT2Config
dtype: jnp.dtype = jnp.float32
def setup(self):
config = self.config
self.embed_dim = config.hidden_size
self.num_heads = config.num_attention_heads
self.head_dim = self.embed_dim // self.num_heads
self.c_attn = FlaxConv1D(features=3 * self.embed_dim, dtype=self.dtype)
self.c_proj = FlaxConv1D(self.embed_dim, dtype=self.dtype)
self.resid_dropout = nn.Dropout(rate=config.resid_pdrop)
self.causal_mask = make_causal_mask(jnp.ones((1, config.max_position_embeddings), dtype="bool"), dtype="bool")
def _split_heads(self, hidden_states):
return hidden_states.reshape(hidden_states.shape[:2] + (self.num_heads, self.head_dim))
def _merge_heads(self, hidden_states):
return hidden_states.reshape(hidden_states.shape[:2] + (self.embed_dim,))
@nn.compact
def _concatenate_to_cache(self, key, value, query, attention_mask):
"""
This function takes projected key, value states from a single input token and concatenates the states to cached
states from previous steps. This function is slighly adapted from the official Flax repository:
https://github.com/google/flax/blob/491ce18759622506588784b4fca0e4bf05f8c8cd/flax/linen/attention.py#L252
"""
# detect if we're initializing by absence of existing cache data.
is_initialized = self.has_variable("cache", "cached_key")
cached_key = self.variable("cache", "cached_key", jnp.zeros, key.shape, key.dtype)
cached_value = self.variable("cache", "cached_value", jnp.zeros, value.shape, value.dtype)
cache_index = self.variable("cache", "cache_index", lambda: jnp.array(0, dtype=jnp.int32))
if is_initialized:
*batch_dims, max_length, num_heads, depth_per_head = cached_key.value.shape
# update key, value caches with our new 1d spatial slices
cur_index = cache_index.value
indices = (0,) * len(batch_dims) + (cur_index, 0, 0)
key = lax.dynamic_update_slice(cached_key.value, key, indices)
value = lax.dynamic_update_slice(cached_value.value, value, indices)
cached_key.value = key
cached_value.value = value
num_updated_cache_vectors = query.shape[1]
cache_index.value = cache_index.value + num_updated_cache_vectors
# causal mask for cached decoder self-attention: our single query position should only attend to those key positions that have already been generated and cached, not the remaining zero elements.
pad_mask = jnp.broadcast_to(
jnp.arange(max_length) < cur_index + num_updated_cache_vectors,
tuple(batch_dims) + (1, num_updated_cache_vectors, max_length),
)
attention_mask = combine_masks(pad_mask, attention_mask)
return key, value, attention_mask
def __call__(
self,
hidden_states,
attention_mask=None,
deterministic: bool = True,
init_cache: bool = False,
output_attentions: bool = False,
):
qkv_out = self.c_attn(hidden_states)
query, key, value = jnp.split(qkv_out, 3, axis=2)
query = self._split_heads(query)
key = self._split_heads(key)
value = self._split_heads(value)
query_length, key_length = query.shape[1], key.shape[1]
if self.has_variable("cache", "cached_key"):
mask_shift = self.variables["cache"]["cache_index"]
max_decoder_length = self.variables["cache"]["cached_key"].shape[1]
causal_mask = lax.dynamic_slice(
self.causal_mask, (0, 0, mask_shift, 0), (1, 1, query_length, max_decoder_length)
)
else:
causal_mask = self.causal_mask[:, :, :query_length, :key_length]
batch_size = hidden_states.shape[0]
causal_mask = jnp.broadcast_to(causal_mask, (batch_size,) + causal_mask.shape[1:])
attention_mask = jnp.broadcast_to(jnp.expand_dims(attention_mask, axis=(-3, -2)), causal_mask.shape)
attention_mask = combine_masks(attention_mask, causal_mask)
dropout_rng = None
if not deterministic and self.config.attn_pdrop > 0.0:
dropout_rng = self.make_rng("dropout")
# During fast autoregressive decoding, we feed one position at a time,
# and cache the keys and values step by step.
if self.has_variable("cache", "cached_key") or init_cache:
key, value, attention_mask = self._concatenate_to_cache(key, value, query, attention_mask)
# transform boolean mask into float mask
attention_bias = lax.select(
attention_mask > 0,
jnp.full(attention_mask.shape, 0.0).astype(self.dtype),
jnp.full(attention_mask.shape, -1e4).astype(self.dtype),
)
# usual dot product attention
attn_output = dot_product_attention(
query,
key,
value,
bias=attention_bias,
dropout_rng=dropout_rng,
dropout_rate=self.config.attn_pdrop,
deterministic=deterministic,
dtype=self.dtype,
precision=None,
)
attn_output = self._merge_heads(attn_output)
attn_output = self.c_proj(attn_output)
attn_output = self.resid_dropout(attn_output, deterministic=deterministic)
# TODO: at the moment it's not possible to retrieve attn_weights from
# dot_product_attention, but should be in the future -> add functionality then
return (attn_output,)
class FlaxGPT2MLP(nn.Module):
config: GPT2Config
intermediate_size: int
dtype: jnp.dtype = jnp.float32
def setup(self):
embed_dim = self.config.hidden_size
self.c_fc = FlaxConv1D(self.intermediate_size, dtype=self.dtype)
self.c_proj = FlaxConv1D(embed_dim, dtype=self.dtype)
self.act = ACT2FN[self.config.activation_function]
self.dropout = nn.Dropout(rate=self.config.resid_pdrop)
def __call__(self, hidden_states, deterministic: bool = True):
hidden_states = self.c_fc(hidden_states)
hidden_states = self.act(hidden_states)
hidden_states = self.c_proj(hidden_states)
hidden_states = self.dropout(hidden_states, deterministic=deterministic)
return hidden_states
class FlaxGPT2Block(nn.Module):
config: GPT2Config
dtype: jnp.dtype = jnp.float32
def setup(self):
hidden_size = self.config.hidden_size
inner_dim = self.config.n_inner if self.config.n_inner is not None else 4 * hidden_size
self.ln_1 = nn.LayerNorm(epsilon=self.config.layer_norm_epsilon, dtype=self.dtype)
self.attn = FlaxGPT2Attention(self.config, dtype=self.dtype)
self.ln_2 = nn.LayerNorm(epsilon=self.config.layer_norm_epsilon, dtype=self.dtype)
self.mlp = FlaxGPT2MLP(self.config, inner_dim, dtype=self.dtype)
def __call__(
self,
hidden_states,
attention_mask=None,
deterministic: bool = True,
init_cache: bool = False,
output_attentions: bool = False,
):
residual = hidden_states
hidden_states = self.ln_1(hidden_states)
outputs = self.attn(
hidden_states,
attention_mask=attention_mask,
deterministic=deterministic,
init_cache=init_cache,
output_attentions=output_attentions,
)
# residual connection
attn_output = outputs[0]
hidden_states = attn_output + residual
residual = hidden_states
hidden_states = self.ln_2(hidden_states)
feed_forward_hidden_states = self.mlp(hidden_states, deterministic=deterministic)
# residual connection
hidden_states = residual + feed_forward_hidden_states
return (hidden_states,) + outputs[1:]
class FlaxGPT2PreTrainedModel(FlaxPreTrainedModel):
"""
An abstract class to handle weights initialization and a simple interface for downloading and loading pretrained
models.
"""
config_class = GPT2Config
base_model_prefix = "transformer"
module_class: nn.Module = None
def __init__(
self,
config: GPT2Config,
input_shape: Tuple = (1, 1),
seed: int = 0,
dtype: jnp.dtype = jnp.float32,
**kwargs,
):
module = self.module_class(config=config, dtype=dtype, **kwargs)
super().__init__(config, module, input_shape=input_shape, seed=seed, dtype=dtype)
@property
def _attn_layer_name(self):
attn_layer_key_tuple = ("h", "0", "attn")
if self.base_model_prefix in set(self.params.keys()):
attn_layer_key_tuple = (self.base_model_prefix,) + attn_layer_key_tuple
return attn_layer_key_tuple
def init_weights(self, rng: jax.random.PRNGKey, input_shape: Tuple) -> FrozenDict:
# init input tensors
input_ids = jnp.zeros(input_shape, dtype="i4")
attention_mask = jnp.ones_like(input_ids)
position_ids = jnp.broadcast_to(jnp.arange(jnp.atleast_2d(input_ids).shape[-1]), input_shape)
params_rng, dropout_rng = jax.random.split(rng)
rngs = {"params": params_rng, "dropout": dropout_rng}
return self.module.init(rngs, input_ids, attention_mask, position_ids, return_dict=False)["params"]
def init_cache(self, batch_size, max_length):
r"""
Args:
batch_size (:obj:`int`):
batch_size used for fast auto-regressive decoding. Defines the batch size of the initialized cache.
max_length (:obj:`int`):
maximum possible length for auto-regressive decoding. Defines the sequence length of the initialized
cache.
"""
# init input variables to retrieve cache
input_ids = jnp.ones((batch_size, max_length))
attention_mask = jnp.ones_like(input_ids)
position_ids = jnp.broadcast_to(jnp.arange(jnp.atleast_2d(input_ids).shape[-1]), input_ids.shape)
init_variables = self.module.init(
jax.random.PRNGKey(0), input_ids, attention_mask, position_ids, return_dict=False, init_cache=True
)
return init_variables["cache"]
@add_start_docstrings_to_model_forward(GPT2_INPUTS_DOCSTRING)
def __call__(
self,
input_ids,
attention_mask=None,
position_ids=None,
params: dict = None,
past_key_values: dict = None,
dropout_rng: jax.random.PRNGKey = None,
train: bool = False,
output_attentions: Optional[bool] = None,
output_hidden_states: Optional[bool] = None,
return_dict: Optional[bool] = None,
):
output_attentions = output_attentions if output_attentions is not None else self.config.output_attentions
output_hidden_states = (
output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states
)
return_dict = return_dict if return_dict is not None else self.config.return_dict
batch_size, sequence_length = input_ids.shape
if position_ids is None:
if past_key_values is not None and input_ids.shape[-1] == 1:
# if `past_key_values` are passed and input_ids are longer than 1, we are in cached auto-regressive generation. It has to be made sure that position_ids are set correctly
cache_shift = flatten_dict(unfreeze(past_key_values))[self._attn_layer_name + ("cache_index",)]
position_ids = jnp.broadcast_to(
jnp.arange(self.config.max_position_embeddings)[None, :],
(batch_size, self.config.max_position_embeddings),
)
position_ids = lax.dynamic_slice(position_ids, (0, cache_shift), (batch_size, 1))
else:
position_ids = jnp.broadcast_to(jnp.arange(sequence_length)[None, :], (batch_size, sequence_length))
if attention_mask is None:
# if past_key_values are passed we need to create an attention_mask of the same length as `cache_length`
if past_key_values is not None:
cache_length = flatten_dict(unfreeze(past_key_values))[self._attn_layer_name + ("cached_key",)].shape[
1
]
else:
cache_length = sequence_length
# Note that usually one would have to put 0's in the attention_mask for x > input_ids.shape[-1] and x < cache_length. But since GPT2 uses a causal mask, those positions are masked anyways. Thus we can create a single static attention_mask here, which is more efficient for compilation
attention_mask = jnp.ones((batch_size, cache_length))
# Handle any PRNG if needed
rngs = {}
if dropout_rng is not None:
rngs["dropout"] = dropout_rng
inputs = {"params": params or self.params}
# if past_key_values are passed then cache is already initialized a private flag init_cache has to be passed down to ensure cache is used. It has to be made sure that cache is marked as mutable so that it can be changed by FlaxGPT2Attention module
if past_key_values:
inputs["cache"] = past_key_values
mutable = ["cache"]
else:
mutable = False
outputs = self.module.apply(
inputs,
jnp.array(input_ids, dtype="i4"),
jnp.array(attention_mask, dtype="i4"),
jnp.array(position_ids, dtype="i4"),
not train,
False,
output_attentions,
output_hidden_states,
return_dict,
rngs=rngs,
mutable=mutable,
)
# add updated cache to model output
if past_key_values is not None and return_dict:
outputs, past_key_values = outputs
outputs["past_key_values"] = unfreeze(past_key_values["cache"])
return outputs
elif past_key_values is not None and not return_dict:
outputs, past_key_values = outputs
outputs = outputs[:1] + (unfreeze(past_key_values["cache"]),) + outputs[1:]
return outputs
class FlaxGPT2BlockCollection(nn.Module):
config: GPT2Config
dtype: jnp.dtype = jnp.float32
def setup(self):
self.blocks = [
FlaxGPT2Block(self.config, name=str(i), dtype=self.dtype) for i in range(self.config.num_hidden_layers)
]
def __call__(
self,
hidden_states,
attention_mask=None,
deterministic: bool = True,
init_cache: bool = False,
output_attentions: bool = False,
output_hidden_states: bool = False,
return_dict: bool = True,
):
all_attentions = () if output_attentions else None
all_hidden_states = () if output_hidden_states else None
for block in self.blocks:
if output_hidden_states:
all_hidden_states += (hidden_states,)
layer_outputs = block(hidden_states, attention_mask, deterministic=deterministic, init_cache=init_cache)
hidden_states = layer_outputs[0]
if output_attentions:
all_attentions += (layer_outputs[1],)
if output_hidden_states:
all_hidden_states += (hidden_states,)
outputs = (hidden_states,)
if not return_dict:
return tuple(v for v in outputs if v is not None)
return FlaxBaseModelOutputWithPast(
last_hidden_state=hidden_states,
past_key_values=None,
hidden_states=all_hidden_states,
attentions=all_attentions,
)
class FlaxGPT2Module(nn.Module):
config: GPT2Config
dtype: jnp.dtype = jnp.float32
def setup(self):
self.embed_dim = self.config.hidden_size
self.wte = nn.Embed(
self.config.vocab_size,
self.embed_dim,
embedding_init=jax.nn.initializers.normal(stddev=self.config.initializer_range),
dtype=self.dtype,
)
self.wpe = nn.Embed(
self.config.max_position_embeddings,
self.embed_dim,
embedding_init=jax.nn.initializers.normal(stddev=self.config.initializer_range),
dtype=self.dtype,
)
self.dropout = nn.Dropout(rate=self.config.embd_pdrop)
self.h = FlaxGPT2BlockCollection(self.config, dtype=self.dtype)
self.ln_f = nn.LayerNorm(epsilon=self.config.layer_norm_epsilon, dtype=self.dtype)
def __call__(
self,
input_ids,
attention_mask,
position_ids,
deterministic=True,
init_cache: bool = False,
output_attentions: bool = False,
output_hidden_states: bool = False,
return_dict: bool = True,
):
input_embeds = self.wte(input_ids.astype("i4"))
position_embeds = self.wpe(position_ids.astype("i4"))
hidden_states = input_embeds + position_embeds
hidden_states = self.dropout(hidden_states, deterministic=deterministic)
outputs = self.h(
hidden_states,
attention_mask,
deterministic=deterministic,
init_cache=init_cache,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
return_dict=return_dict,
)
hidden_states = outputs[0]
hidden_states = self.ln_f(hidden_states)
if not return_dict:
return (hidden_states,) + outputs[1:]
return FlaxBaseModelOutput(
last_hidden_state=hidden_states,
hidden_states=outputs.hidden_states,
attentions=outputs.attentions,
)
@add_start_docstrings(
"The bare GPT2 Model transformer outputting raw hidden-states without any specific head on top.",
GPT2_START_DOCSTRING,
)
class FlaxGPT2Model(FlaxGPT2PreTrainedModel):
module_class = FlaxGPT2Module
append_call_sample_docstring(
FlaxGPT2Model, _TOKENIZER_FOR_DOC, _CHECKPOINT_FOR_DOC, FlaxBaseModelOutput, _CONFIG_FOR_DOC
)
class FlaxGPT2LMHeadModule(nn.Module):
config: GPT2Config
dtype: jnp.dtype = jnp.float32
def setup(self):
self.transformer = FlaxGPT2Module(self.config, dtype=self.dtype)
self.lm_head = nn.Dense(
self.config.vocab_size,
use_bias=False,
dtype=self.dtype,
kernel_init=jax.nn.initializers.normal(stddev=self.config.initializer_range, dtype=self.dtype),
)
def __call__(
self,
input_ids,
attention_mask,
position_ids,
deterministic: bool = True,
init_cache: bool = False,
output_attentions: bool = False,
output_hidden_states: bool = False,
return_dict: bool = True,
):
outputs = self.transformer(
input_ids,
attention_mask,
position_ids,
deterministic=deterministic,
init_cache=init_cache,
output_attentions=output_attentions,
output_hidden_states=output_hidden_states,
return_dict=return_dict,
)
hidden_states = outputs[0]
if self.config.tie_word_embeddings:
shared_kernel = self.transformer.variables["params"]["wte"]["embedding"].T
lm_logits = self.lm_head.apply({"params": {"kernel": shared_kernel}}, hidden_states)
else:
lm_logits = self.lm_head(hidden_states)
if not return_dict:
return (lm_logits,) + outputs[1:]
return FlaxCausalLMOutput(logits=lm_logits, hidden_states=outputs.hidden_states, attentions=outputs.attentions)
@add_start_docstrings(
"""
The GPT2 Model transformer with a language modeling head on top (linear layer with weights tied to the input
embeddings).
""",
GPT2_START_DOCSTRING,
)
class FlaxGPT2LMHeadModel(FlaxGPT2PreTrainedModel):
module_class = FlaxGPT2LMHeadModule
append_call_sample_docstring(
FlaxGPT2LMHeadModel, _TOKENIZER_FOR_DOC, _CHECKPOINT_FOR_DOC, FlaxCausalLMOutput, _CONFIG_FOR_DOC
)

View File

@ -11,6 +11,9 @@ class FlaxPreTrainedModel:
requires_backends(self, ["flax"])
FLAX_MODEL_FOR_CAUSAL_LM_MAPPING = None
FLAX_MODEL_FOR_MASKED_LM_MAPPING = None
@ -44,6 +47,15 @@ class FlaxAutoModel:
requires_backends(self, ["flax"])
class FlaxAutoModelForCausalLM:
def __init__(self, *args, **kwargs):
requires_backends(self, ["flax"])
@classmethod
def from_pretrained(self, *args, **kwargs):
requires_backends(self, ["flax"])
class FlaxAutoModelForMaskedLM:
def __init__(self, *args, **kwargs):
requires_backends(self, ["flax"])
@ -248,6 +260,24 @@ class FlaxElectraPreTrainedModel:
requires_backends(self, ["flax"])
class FlaxGPT2LMHeadModel:
def __init__(self, *args, **kwargs):
requires_backends(self, ["flax"])
@classmethod
def from_pretrained(self, *args, **kwargs):
requires_backends(self, ["flax"])
class FlaxGPT2Model:
def __init__(self, *args, **kwargs):
requires_backends(self, ["flax"])
@classmethod
def from_pretrained(self, *args, **kwargs):
requires_backends(self, ["flax"])
class FlaxRobertaForMaskedLM:
def __init__(self, *args, **kwargs):
requires_backends(self, ["flax"])

View File

@ -247,12 +247,8 @@ class FlaxModelTesterMixin:
model = model_class(config)
@jax.jit
def model_jitted(input_ids, attention_mask=None, token_type_ids=None):
return model(
input_ids=input_ids,
attention_mask=attention_mask,
token_type_ids=token_type_ids,
).to_tuple()
def model_jitted(input_ids, attention_mask=None, **kwargs):
return model(input_ids=input_ids, attention_mask=attention_mask, **kwargs).to_tuple()
with self.subTest("JIT Enabled"):
jitted_outputs = model_jitted(**prepared_inputs_dict)
@ -266,11 +262,11 @@ class FlaxModelTesterMixin:
self.assertEqual(jitted_output.shape, output.shape)
@jax.jit
def model_jitted_return_dict(input_ids, attention_mask=None, token_type_ids=None):
def model_jitted_return_dict(input_ids, attention_mask=None, **kwargs):
return model(
input_ids=input_ids,
attention_mask=attention_mask,
token_type_ids=token_type_ids,
**kwargs,
)
# jitted function cannot return OrderedDict

View File

@ -0,0 +1,332 @@
# Copyright 2021 The HuggingFace Team. All rights reserved.
#
# 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
#
# 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.
import tempfile
import unittest
import numpy as np
import transformers
from transformers import GPT2Config, is_flax_available, is_torch_available
from transformers.testing_utils import is_pt_flax_cross_test, require_flax, slow
from .test_modeling_flax_common import FlaxModelTesterMixin, ids_tensor, random_attention_mask
if is_flax_available():
import jax
import jax.numpy as jnp
from jax import lax
from transformers.modeling_flax_pytorch_utils import (
convert_pytorch_state_dict_to_flax,
load_flax_weights_in_pytorch_model,
)
from transformers.models.gpt2.modeling_flax_gpt2 import FlaxGPT2LMHeadModel, FlaxGPT2Model
if is_torch_available():
import torch
class FlaxGPT2ModelTester:
def __init__(
self,
parent,
batch_size=14,
seq_length=7,
is_training=True,
use_input_mask=True,
use_token_type_ids=False,
use_labels=True,
vocab_size=99,
hidden_size=32,
num_hidden_layers=5,
num_attention_heads=4,
intermediate_size=37,
hidden_act="gelu",
hidden_dropout_prob=0.1,
attention_probs_dropout_prob=0.1,
max_position_embeddings=512,
initializer_range=0.02,
):
self.parent = parent
self.batch_size = batch_size
self.seq_length = seq_length
self.is_training = is_training
self.use_input_mask = use_input_mask
self.use_token_type_ids = use_token_type_ids
self.use_labels = use_labels
self.vocab_size = vocab_size
self.hidden_size = hidden_size
self.num_hidden_layers = num_hidden_layers
self.num_attention_heads = num_attention_heads
self.intermediate_size = intermediate_size
self.hidden_act = hidden_act
self.hidden_dropout_prob = hidden_dropout_prob
self.attention_probs_dropout_prob = attention_probs_dropout_prob
self.max_position_embeddings = max_position_embeddings
self.initializer_range = initializer_range
self.scope = None
self.bos_token_id = vocab_size - 1
self.eos_token_id = vocab_size - 1
self.pad_token_id = vocab_size - 1
def prepare_config_and_inputs(self, gradient_checkpointing=False):
input_ids = ids_tensor([self.batch_size, self.seq_length], self.vocab_size)
input_mask = None
if self.use_input_mask:
input_mask = random_attention_mask([self.batch_size, self.seq_length])
config = GPT2Config(
vocab_size=self.vocab_size,
n_embd=self.hidden_size,
n_layer=self.num_hidden_layers,
n_head=self.num_attention_heads,
n_positions=self.max_position_embeddings,
n_ctx=self.max_position_embeddings,
use_cache=False,
bos_token_id=self.bos_token_id,
eos_token_id=self.eos_token_id,
pad_token_id=self.pad_token_id,
gradient_checkpointing=gradient_checkpointing,
)
return (config, input_ids, input_mask)
def prepare_config_and_inputs_for_common(self):
config_and_inputs = self.prepare_config_and_inputs()
config, input_ids, attention_mask = config_and_inputs
inputs_dict = {"input_ids": input_ids, "attention_mask": attention_mask}
return config, inputs_dict
def check_use_cache_forward(self, model_class_name, config, input_ids, attention_mask):
max_decoder_length = 20
model = model_class_name(config)
past_key_values = model.init_cache(input_ids.shape[0], max_decoder_length)
outputs_cache = model(input_ids[:, :-1], past_key_values=past_key_values)
outputs_cache_next = model(input_ids[:, -1:], past_key_values=outputs_cache.past_key_values)
outputs = model(input_ids)
diff = np.max(np.abs((outputs_cache_next[0][:, -1, :5] - outputs[0][:, -1, :5])))
self.parent.assertTrue(diff < 1e-3, msg=f"Max diff is {diff}")
def check_use_cache_forward_with_attn_mask(self, model_class_name, config, input_ids, attention_mask):
max_decoder_length = 20
model = model_class_name(config)
attention_mask_cache = jnp.concatenate(
[attention_mask, jnp.zeros((attention_mask.shape[0], max_decoder_length - attention_mask.shape[1]))],
axis=-1,
)
past_key_values = model.init_cache(input_ids.shape[0], max_decoder_length)
outputs_cache = model(input_ids[:, :-1], attention_mask=attention_mask_cache, past_key_values=past_key_values)
outputs_cache_next = model(
input_ids[:, -1:], past_key_values=outputs_cache.past_key_values, attention_mask=attention_mask_cache
)
outputs = model(input_ids, attention_mask=attention_mask)
diff = np.max(np.abs((outputs_cache_next[0][:, -1, :5] - outputs[0][:, -1, :5])))
self.parent.assertTrue(diff < 1e-3, msg=f"Max diff is {diff}")
def check_use_cache_generation(self, config, input_ids):
prompt_length = 3
model = FlaxGPT2LMHeadModel(config)
max_length = 10
batch_size = 1
prompt_ids = input_ids[:1, :prompt_length]
# put all generation logic into one function
def generate(prompt_ids):
def first_pass(prompt_ids):
logits, cache = model(prompt_ids, past_key_values=past_key_values)[:2]
next_token = jnp.argmax(logits[:, -1:], axis=-1)
return next_token, cache
def greedy_search_cond_fn(state):
cur_len, _, _, _ = state
return ~(cur_len == max_length - 1)
def greedy_search_body_fn(state):
cur_len, sequences, current_token, cache = state
next_sequences = lax.dynamic_update_slice(sequences, current_token, (0, cur_len))
next_logits, next_cache = model(current_token, past_key_values=cache)[:2]
next_token = jnp.argmax(next_logits, axis=-1)
return cur_len + 1, next_sequences, next_token, next_cache
# init tensor to be filled with generation result
init_sequences = jnp.zeros((batch_size, max_length), dtype="i4")
init_sequences = lax.dynamic_update_slice(init_sequences, prompt_ids, (0, 0))
# init past key values for cache
past_key_values = model.init_cache(batch_size, max_length)
# first pass with long prompt
next_token, cache = first_pass(prompt_ids)
# prepare state for generation loop
init_state = (jnp.array(prompt_length), init_sequences, next_token, cache)
# fast generation
_, output_sequences, final_token, _ = lax.while_loop(
greedy_search_cond_fn, greedy_search_body_fn, init_state
)
# append last token
output_sequences = lax.dynamic_update_slice(output_sequences, final_token, (0, max_length - 1))
return output_sequences
jit_generate = jax.jit(generate)
output_sequences = jit_generate(prompt_ids)
self.parent.assertEqual(output_sequences.shape, (1, max_length))
@require_flax
class FlaxGPT2ModelTest(FlaxModelTesterMixin, unittest.TestCase):
all_model_classes = (FlaxGPT2Model, FlaxGPT2LMHeadModel) if is_flax_available() else ()
def setUp(self):
self.model_tester = FlaxGPT2ModelTester(self)
def test_use_cache_forward(self):
for model_class_name in self.all_model_classes:
config, input_ids, attention_mask = self.model_tester.prepare_config_and_inputs()
self.model_tester.check_use_cache_forward(model_class_name, config, input_ids, attention_mask)
def test_use_cache_forward_with_attn_mask(self):
for model_class_name in self.all_model_classes:
config, input_ids, attention_mask = self.model_tester.prepare_config_and_inputs()
self.model_tester.check_use_cache_forward_with_attn_mask(
model_class_name, config, input_ids, attention_mask
)
def test_use_cache_generation(self):
config, input_ids, _ = self.model_tester.prepare_config_and_inputs()
self.model_tester.check_use_cache_generation(config, input_ids)
# overwrite from common since `attention_mask` in combination
# with `causal_mask` behaves slighly differently
@is_pt_flax_cross_test
def test_equivalence_pt_to_flax(self):
config, inputs_dict = self.model_tester.prepare_config_and_inputs_for_common()
for model_class in self.all_model_classes:
with self.subTest(model_class.__name__):
# prepare inputs
prepared_inputs_dict = self._prepare_for_class(inputs_dict, model_class)
pt_inputs = {k: torch.tensor(v.tolist()) for k, v in prepared_inputs_dict.items()}
# load corresponding PyTorch class
pt_model_class_name = model_class.__name__[4:] # Skip the "Flax" at the beginning
pt_model_class = getattr(transformers, pt_model_class_name)
batch_size, seq_length = pt_inputs["input_ids"].shape
rnd_start_indices = np.random.randint(0, seq_length - 1, size=(batch_size,))
for batch_idx, start_index in enumerate(rnd_start_indices):
pt_inputs["attention_mask"][batch_idx, :start_index] = 0
pt_inputs["attention_mask"][batch_idx, start_index:] = 1
prepared_inputs_dict["attention_mask"][batch_idx, :start_index] = 0
prepared_inputs_dict["attention_mask"][batch_idx, start_index:] = 1
pt_model = pt_model_class(config).eval()
fx_model = model_class(config, dtype=jnp.float32)
fx_state = convert_pytorch_state_dict_to_flax(pt_model.state_dict(), fx_model)
fx_model.params = fx_state
with torch.no_grad():
pt_outputs = pt_model(**pt_inputs).to_tuple()
fx_outputs = fx_model(**prepared_inputs_dict).to_tuple()
self.assertEqual(len(fx_outputs), len(pt_outputs), "Output lengths differ between Flax and PyTorch")
for fx_output, pt_output in zip(fx_outputs, pt_outputs):
self.assert_almost_equals(fx_output[:, -1], pt_output[:, -1].numpy(), 4e-2)
with tempfile.TemporaryDirectory() as tmpdirname:
pt_model.save_pretrained(tmpdirname)
fx_model_loaded = model_class.from_pretrained(tmpdirname, from_pt=True)
fx_outputs_loaded = fx_model_loaded(**prepared_inputs_dict).to_tuple()
self.assertEqual(
len(fx_outputs_loaded), len(pt_outputs), "Output lengths differ between Flax and PyTorch"
)
for fx_output_loaded, pt_output in zip(fx_outputs_loaded, pt_outputs):
self.assert_almost_equals(fx_output_loaded[:, -1], pt_output[:, -1].numpy(), 4e-2)
# overwrite from common since `attention_mask` in combination
# with `causal_mask` behaves slighly differently
@is_pt_flax_cross_test
def test_equivalence_flax_to_pt(self):
config, inputs_dict = self.model_tester.prepare_config_and_inputs_for_common()
for model_class in self.all_model_classes:
with self.subTest(model_class.__name__):
# prepare inputs
prepared_inputs_dict = self._prepare_for_class(inputs_dict, model_class)
pt_inputs = {k: torch.tensor(v.tolist()) for k, v in prepared_inputs_dict.items()}
# load corresponding PyTorch class
pt_model_class_name = model_class.__name__[4:] # Skip the "Flax" at the beginning
pt_model_class = getattr(transformers, pt_model_class_name)
pt_model = pt_model_class(config).eval()
fx_model = model_class(config, dtype=jnp.float32)
pt_model = load_flax_weights_in_pytorch_model(pt_model, fx_model.params)
batch_size, seq_length = pt_inputs["input_ids"].shape
rnd_start_indices = np.random.randint(0, seq_length - 1, size=(batch_size,))
for batch_idx, start_index in enumerate(rnd_start_indices):
pt_inputs["attention_mask"][batch_idx, :start_index] = 0
pt_inputs["attention_mask"][batch_idx, start_index:] = 1
prepared_inputs_dict["attention_mask"][batch_idx, :start_index] = 0
prepared_inputs_dict["attention_mask"][batch_idx, start_index:] = 1
# make sure weights are tied in PyTorch
pt_model.tie_weights()
with torch.no_grad():
pt_outputs = pt_model(**pt_inputs).to_tuple()
fx_outputs = fx_model(**prepared_inputs_dict).to_tuple()
self.assertEqual(len(fx_outputs), len(pt_outputs), "Output lengths differ between Flax and PyTorch")
for fx_output, pt_output in zip(fx_outputs, pt_outputs):
self.assert_almost_equals(fx_output[:, -1], pt_output[:, -1].numpy(), 4e-2)
with tempfile.TemporaryDirectory() as tmpdirname:
fx_model.save_pretrained(tmpdirname)
pt_model_loaded = pt_model_class.from_pretrained(tmpdirname, from_flax=True)
with torch.no_grad():
pt_outputs_loaded = pt_model_loaded(**pt_inputs).to_tuple()
self.assertEqual(
len(fx_outputs), len(pt_outputs_loaded), "Output lengths differ between Flax and PyTorch"
)
for fx_output, pt_output in zip(fx_outputs, pt_outputs_loaded):
self.assert_almost_equals(fx_output[:, -1], pt_output[:, -1].numpy(), 4e-2)
@slow
def test_model_from_pretrained(self):
for model_class_name in self.all_model_classes:
model = model_class_name.from_pretrained("gpt2", from_pt=True)
outputs = model(np.ones((1, 1)))
self.assertIsNotNone(outputs)