Upload folder using huggingface_hub
Browse files- custom_generate/__init__.py +5 -0
- custom_generate/generate.py +1057 -0
- custom_generate/requirements.txt +3 -0
custom_generate/__init__.py
ADDED
|
@@ -0,0 +1,5 @@
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 1 |
+
# Custom generate function for fuzzy speculative decoding
|
| 2 |
+
from .generate import generate
|
| 3 |
+
|
| 4 |
+
__all__ = ["generate"]
|
| 5 |
+
|
custom_generate/generate.py
ADDED
|
@@ -0,0 +1,1057 @@
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| 1 |
+
# coding=utf-8
|
| 2 |
+
# Custom generate function for fuzzy speculative decoding
|
| 3 |
+
# Based on transformers.generation.utils with modifications for custom acceptance/rejection logic
|
| 4 |
+
|
| 5 |
+
import copy
|
| 6 |
+
import inspect
|
| 7 |
+
import warnings
|
| 8 |
+
from collections.abc import Callable
|
| 9 |
+
from dataclasses import dataclass
|
| 10 |
+
from typing import TYPE_CHECKING, Any, Optional, Union
|
| 11 |
+
|
| 12 |
+
import torch
|
| 13 |
+
import torch.distributed as dist
|
| 14 |
+
from torch import nn
|
| 15 |
+
|
| 16 |
+
from torch.nn.functional import kl_div, log_softmax
|
| 17 |
+
|
| 18 |
+
from transformers.cache_utils import Cache
|
| 19 |
+
from transformers.generation.candidate_generator import (
|
| 20 |
+
AssistedCandidateGenerator,
|
| 21 |
+
_prepare_attention_mask,
|
| 22 |
+
_prepare_token_type_ids,
|
| 23 |
+
)
|
| 24 |
+
from transformers.generation.configuration_utils import GenerationConfig, GenerationMode
|
| 25 |
+
from transformers.generation.logits_process import LogitsProcessorList
|
| 26 |
+
from transformers.generation.stopping_criteria import StoppingCriteriaList
|
| 27 |
+
from transformers.utils import ModelOutput, is_sklearn_available
|
| 28 |
+
|
| 29 |
+
if is_sklearn_available():
|
| 30 |
+
from sklearn.metrics import roc_curve
|
| 31 |
+
|
| 32 |
+
if TYPE_CHECKING:
|
| 33 |
+
from transformers.modeling_utils import PreTrainedModel
|
| 34 |
+
from transformers.tokenization_utils_base import PreTrainedTokenizerBase
|
| 35 |
+
from transformers.generation.streamers import BaseStreamer
|
| 36 |
+
|
| 37 |
+
# Variable names used to hold the cache at generation time
|
| 38 |
+
ALL_CACHE_NAMES = [
|
| 39 |
+
"past_key_values", # default
|
| 40 |
+
"cache_params", # mamba-based models
|
| 41 |
+
"state", # rwkv
|
| 42 |
+
"mems", # xlnet
|
| 43 |
+
"past_buckets_states", # reformer
|
| 44 |
+
]
|
| 45 |
+
|
| 46 |
+
GENERATION_MODES_MAPPING = {
|
| 47 |
+
GenerationMode.SAMPLE: "_sample",
|
| 48 |
+
GenerationMode.GREEDY_SEARCH: "_sample",
|
| 49 |
+
GenerationMode.BEAM_SEARCH: "_beam_search",
|
| 50 |
+
GenerationMode.BEAM_SAMPLE: "_beam_search",
|
| 51 |
+
GenerationMode.ASSISTED_GENERATION: "_assisted_decoding",
|
| 52 |
+
}
|
| 53 |
+
|
| 54 |
+
|
| 55 |
+
@dataclass
|
| 56 |
+
class GenerateDecoderOnlyOutput(ModelOutput):
|
| 57 |
+
"""Outputs of decoder-only generation models, when using non-beam methods."""
|
| 58 |
+
|
| 59 |
+
sequences: torch.LongTensor
|
| 60 |
+
scores: tuple[torch.FloatTensor] | None = None
|
| 61 |
+
logits: tuple[torch.FloatTensor] | None = None
|
| 62 |
+
attentions: tuple[tuple[torch.FloatTensor]] | None = None
|
| 63 |
+
hidden_states: tuple[tuple[torch.FloatTensor]] | None = None
|
| 64 |
+
past_key_values: Cache | None = None
|
| 65 |
+
|
| 66 |
+
|
| 67 |
+
@dataclass
|
| 68 |
+
class GenerateEncoderDecoderOutput(ModelOutput):
|
| 69 |
+
"""Outputs of encoder-decoder generation models, when using non-beam methods."""
|
| 70 |
+
|
| 71 |
+
sequences: torch.LongTensor
|
| 72 |
+
scores: tuple[torch.FloatTensor] | None = None
|
| 73 |
+
logits: tuple[torch.FloatTensor] | None = None
|
| 74 |
+
encoder_attentions: tuple[torch.FloatTensor] | None = None
|
| 75 |
+
encoder_hidden_states: tuple[torch.FloatTensor] | None = None
|
| 76 |
+
decoder_attentions: tuple[tuple[torch.FloatTensor]] | None = None
|
| 77 |
+
cross_attentions: tuple[tuple[torch.FloatTensor]] | None = None
|
| 78 |
+
decoder_hidden_states: tuple[tuple[torch.FloatTensor]] | None = None
|
| 79 |
+
past_key_values: Cache | None = None
|
| 80 |
+
|
| 81 |
+
|
| 82 |
+
def _split_model_outputs(outputs, new_outputs, cur_len, added_len, is_decoder_attention=False):
|
| 83 |
+
"""
|
| 84 |
+
Given the (decoder/cross attentions)/(decoder hidden states) for multiple generated tokens, splits it into a tuple
|
| 85 |
+
where each member corresponds to a single generated token.
|
| 86 |
+
"""
|
| 87 |
+
# Retrocompatibility: in our generation functions, the first iteration includes the attention/hidden states for the
|
| 88 |
+
# prompt.
|
| 89 |
+
if len(outputs) == 0:
|
| 90 |
+
new_tuple = ()
|
| 91 |
+
for layer in new_outputs:
|
| 92 |
+
last_dim_size = cur_len if is_decoder_attention else layer.shape[-1]
|
| 93 |
+
new_tuple += (layer[..., :cur_len, :last_dim_size],)
|
| 94 |
+
outputs += (new_tuple,)
|
| 95 |
+
# The first iteration contains the prompt + 1 generated token, let's update the length variables accordingly
|
| 96 |
+
cur_len += 1
|
| 97 |
+
added_len -= cur_len
|
| 98 |
+
|
| 99 |
+
for i in range(added_len):
|
| 100 |
+
new_tuple = ()
|
| 101 |
+
for layer in new_outputs:
|
| 102 |
+
last_dim_size = cur_len + i if is_decoder_attention else layer.shape[-1]
|
| 103 |
+
new_tuple += (layer[..., i : i + 1, :last_dim_size],)
|
| 104 |
+
outputs += (new_tuple,)
|
| 105 |
+
return outputs
|
| 106 |
+
|
| 107 |
+
|
| 108 |
+
class RawLogitsCandidateGenerator(AssistedCandidateGenerator):
|
| 109 |
+
"""
|
| 110 |
+
Custom candidate generator that returns both processed and raw logits from the assistant model.
|
| 111 |
+
Extends AssistedCandidateGenerator to support returning raw logits when output_logits=True.
|
| 112 |
+
"""
|
| 113 |
+
|
| 114 |
+
def __init__(self, *args, **kwargs):
|
| 115 |
+
"""Initialize the custom candidate generator."""
|
| 116 |
+
super().__init__(*args, **kwargs)
|
| 117 |
+
# Initialize probs list if sklearn is available and confidence threshold is enabled
|
| 118 |
+
if (
|
| 119 |
+
is_sklearn_available()
|
| 120 |
+
and self.assistant_generation_config.assistant_confidence_threshold
|
| 121 |
+
):
|
| 122 |
+
if not hasattr(self, 'probs'):
|
| 123 |
+
self.probs = []
|
| 124 |
+
if not hasattr(self, 'matches'):
|
| 125 |
+
self.matches = []
|
| 126 |
+
|
| 127 |
+
def get_candidates(self, input_ids: torch.LongTensor) -> tuple[torch.LongTensor, torch.FloatTensor | None, torch.FloatTensor | None]:
|
| 128 |
+
"""
|
| 129 |
+
Fetches the candidates to be tried for the current input.
|
| 130 |
+
Returns: (candidate_ids, candidate_logits_processed, candidate_logits_raw)
|
| 131 |
+
- candidate_logits_processed: Processed logits (scores) from assistant model
|
| 132 |
+
- candidate_logits_raw: Raw logits from assistant model (None if output_logits=False)
|
| 133 |
+
"""
|
| 134 |
+
input_ids = input_ids.to(self.assistant_model.device)
|
| 135 |
+
# Calculate new tokens to generate
|
| 136 |
+
min_new_tokens, max_new_tokens = self._calculate_new_tokens(input_ids)
|
| 137 |
+
if max_new_tokens == 0:
|
| 138 |
+
return input_ids, None, None
|
| 139 |
+
# Update past key values and masks
|
| 140 |
+
self._update_past_and_masks(input_ids)
|
| 141 |
+
# Generate candidates
|
| 142 |
+
generation_args = self._prepare_generation_args(input_ids, min_new_tokens, max_new_tokens)
|
| 143 |
+
candidate_ids, candidate_logits_processed, candidate_logits_raw = self._generate_candidates(generation_args)
|
| 144 |
+
return candidate_ids, candidate_logits_processed, candidate_logits_raw
|
| 145 |
+
|
| 146 |
+
def _generate_candidates(self, generation_args: dict) -> tuple[torch.LongTensor, torch.FloatTensor | None, torch.FloatTensor | None]:
|
| 147 |
+
"""Generate candidate sequences using the assistant model, returning both processed and raw logits."""
|
| 148 |
+
assistant_output = self.assistant_model.generate(**generation_args, **self.assistant_kwargs)
|
| 149 |
+
self.assistant_kwargs["past_key_values"] = assistant_output.past_key_values
|
| 150 |
+
|
| 151 |
+
# Handle sklearn confidence threshold tracking (if enabled)
|
| 152 |
+
if (
|
| 153 |
+
is_sklearn_available()
|
| 154 |
+
and self.assistant_generation_config.assistant_confidence_threshold
|
| 155 |
+
and type(self) is RawLogitsCandidateGenerator
|
| 156 |
+
):
|
| 157 |
+
scores_tensor = torch.cat(assistant_output.scores, dim=0)
|
| 158 |
+
scores_softmax = torch.softmax(scores_tensor, dim=-1)
|
| 159 |
+
ids = assistant_output.sequences[-1, -len(assistant_output.scores) :]
|
| 160 |
+
p = scores_softmax[range(len(ids)), ids]
|
| 161 |
+
self.probs.extend(p.tolist())
|
| 162 |
+
|
| 163 |
+
# Extract processed logits (scores) - always available
|
| 164 |
+
candidate_logits_processed = torch.stack(assistant_output.scores, dim=1)
|
| 165 |
+
candidate_ids = assistant_output.sequences
|
| 166 |
+
|
| 167 |
+
# Extract raw logits if available (when output_logits=True)
|
| 168 |
+
candidate_logits_raw = None
|
| 169 |
+
if self.generation_config.output_logits and hasattr(assistant_output, 'logits') and assistant_output.logits is not None:
|
| 170 |
+
candidate_logits_raw = torch.stack(assistant_output.logits, dim=1)
|
| 171 |
+
|
| 172 |
+
return candidate_ids, candidate_logits_processed, candidate_logits_raw
|
| 173 |
+
|
| 174 |
+
|
| 175 |
+
def _speculative_sampling(
|
| 176 |
+
candidate_input_ids,
|
| 177 |
+
candidate_logits,
|
| 178 |
+
candidate_length,
|
| 179 |
+
new_logits,
|
| 180 |
+
next_token_logits,
|
| 181 |
+
is_done_candidate,
|
| 182 |
+
candidate_logits_raw,
|
| 183 |
+
fsd_threshold: float = 0.0,
|
| 184 |
+
fsd_div_type: str = "kl"
|
| 185 |
+
):
|
| 186 |
+
"""
|
| 187 |
+
Applies sampling as in the speculative decoding paper (https://huggingface.co/papers/2211.17192, algorithm 1). Returns
|
| 188 |
+
the selected tokens, as well as the number of candidate matches.
|
| 189 |
+
|
| 190 |
+
NOTE: Unless otherwise stated, the variable names match those in the paper.
|
| 191 |
+
|
| 192 |
+
"""
|
| 193 |
+
new_candidate_input_ids = candidate_input_ids[:, -candidate_length:]
|
| 194 |
+
# Gets the probabilities from the logits. q_i and p_i denote the assistant and model probabilities of the tokens
|
| 195 |
+
# selected by the assistant, respectively.
|
| 196 |
+
q = candidate_logits.softmax(dim=-1)
|
| 197 |
+
q_i = q[:, torch.arange(candidate_length), new_candidate_input_ids].squeeze(0, 1)
|
| 198 |
+
p = new_logits.softmax(dim=-1)
|
| 199 |
+
p_i = p[:, torch.arange(candidate_length), new_candidate_input_ids].squeeze(0, 1)
|
| 200 |
+
probability_ratio = p_i / q_i
|
| 201 |
+
|
| 202 |
+
target_probs = next_token_logits.softmax(dim=-1)
|
| 203 |
+
cand_probs = candidate_logits_raw.softmax(dim=-1)
|
| 204 |
+
|
| 205 |
+
if fsd_div_type == "kl":
|
| 206 |
+
divs = kl_div(
|
| 207 |
+
cand_probs.log().clamp(min=-1e10), # log-probabilities of candidate distribution
|
| 208 |
+
target_probs[:, :-1, :], # probabilities of target distribution
|
| 209 |
+
reduction='none'
|
| 210 |
+
).sum(dim=-1)
|
| 211 |
+
elif fsd_div_type == "js":
|
| 212 |
+
|
| 213 |
+
m = 0.5 * (cand_probs + target_probs[:, :-1, :]) # Mixture distribution
|
| 214 |
+
|
| 215 |
+
# Compute KL(P || M) and KL(Q || M)
|
| 216 |
+
kl_pm = kl_div(
|
| 217 |
+
m.log().clamp(min=-1e10), # log-probabilities of mixture
|
| 218 |
+
cand_probs, # probabilities of candidate
|
| 219 |
+
reduction='none'
|
| 220 |
+
)
|
| 221 |
+
kl_qm = kl_div(
|
| 222 |
+
m.log().clamp(min=-1e10), # log-probabilities of mixture
|
| 223 |
+
target_probs[:, :-1, :], # probabilities of target
|
| 224 |
+
reduction='none'
|
| 225 |
+
)
|
| 226 |
+
|
| 227 |
+
divs = 0.5 * (kl_pm + kl_qm).sum(dim=-1)
|
| 228 |
+
|
| 229 |
+
elif fsd_div_type == "draft_tokens":
|
| 230 |
+
draft_token_ids = new_candidate_input_ids # shape: (batch, candidate_length)
|
| 231 |
+
draft_token_probs_candidate = cand_probs[:, torch.arange(candidate_length), draft_token_ids].squeeze(0, 1)
|
| 232 |
+
draft_token_probs_target = target_probs[:, :-1, :][:, torch.arange(candidate_length), draft_token_ids].squeeze(0,
|
| 233 |
+
1)
|
| 234 |
+
divs = (draft_token_probs_candidate - draft_token_probs_target).abs().sum(dim=-1)
|
| 235 |
+
else:
|
| 236 |
+
raise ValueError(f"Invalid fsd_div_type: {fsd_div_type}")
|
| 237 |
+
# print(f"divs: {divs}")
|
| 238 |
+
is_accepted_fsd = divs <= fsd_threshold
|
| 239 |
+
|
| 240 |
+
# When probability_ratio > 1 (i.e. q_i(x) < p_i(x), or "assistant probability of the candidate token is smaller
|
| 241 |
+
# than the model probability for the same token"), keep the token. Otherwise reject with p = 1 - probability_ratio
|
| 242 |
+
# (= keep with p = probability_ratio). Keep all the tokens until the first rejection
|
| 243 |
+
r_i = torch.rand_like(probability_ratio)
|
| 244 |
+
is_accepted_sd = r_i <= probability_ratio
|
| 245 |
+
|
| 246 |
+
is_accepted = is_accepted_fsd | is_accepted_sd
|
| 247 |
+
n_matches = ((~is_accepted).cumsum(dim=-1) < 1).sum() # this is `n` in algorithm 1
|
| 248 |
+
# print(f"is_accepted_fsd: {is_accepted_fsd}\n is_accepted_sd: {is_accepted_sd}\n is_accepted: {is_accepted}")
|
| 249 |
+
|
| 250 |
+
# Ensure we don't generate beyond max_len or an EOS token (not in algorithm 1, but needed for correct behavior)
|
| 251 |
+
if is_done_candidate and n_matches == candidate_length:
|
| 252 |
+
# Output length is assumed to be `n_matches + 1`. Since we won't generate another token with the target model
|
| 253 |
+
# due to acceptance on EOS we fix `n_matches`
|
| 254 |
+
n_matches -= 1
|
| 255 |
+
valid_tokens = new_candidate_input_ids[:, : n_matches + 1]
|
| 256 |
+
else:
|
| 257 |
+
# Next token selection: if there is a rejection, adjust the distribution from the main model before sampling.
|
| 258 |
+
gamma = candidate_logits.shape[1]
|
| 259 |
+
p_n_plus_1 = p[:, n_matches, :]
|
| 260 |
+
if n_matches < gamma:
|
| 261 |
+
q_n_plus_1 = q[:, n_matches, :]
|
| 262 |
+
p_prime = torch.clamp((p_n_plus_1 - q_n_plus_1), min=0)
|
| 263 |
+
p_prime.div_(p_prime.sum())
|
| 264 |
+
else:
|
| 265 |
+
p_prime = p_n_plus_1
|
| 266 |
+
t = torch.multinomial(p_prime, num_samples=1).squeeze(1)[None, :]
|
| 267 |
+
|
| 268 |
+
# The selected tokens include the matches (if any) plus the next sampled tokens
|
| 269 |
+
if n_matches > 0:
|
| 270 |
+
valid_tokens = torch.cat((new_candidate_input_ids[:, :n_matches], t), dim=-1)
|
| 271 |
+
else:
|
| 272 |
+
valid_tokens = t
|
| 273 |
+
|
| 274 |
+
return valid_tokens, n_matches
|
| 275 |
+
|
| 276 |
+
|
| 277 |
+
def _assisted_decoding(
|
| 278 |
+
model,
|
| 279 |
+
input_ids: torch.LongTensor,
|
| 280 |
+
logits_processor: LogitsProcessorList,
|
| 281 |
+
stopping_criteria: StoppingCriteriaList,
|
| 282 |
+
generation_config: GenerationConfig,
|
| 283 |
+
synced_gpus: bool = False,
|
| 284 |
+
streamer: Optional["BaseStreamer"] = None,
|
| 285 |
+
inputs_tensor: torch.FloatTensor | None = None,
|
| 286 |
+
assistant_model: Optional["PreTrainedModel"] = None,
|
| 287 |
+
assistant_tokenizer: Optional["PreTrainedTokenizerBase"] = None,
|
| 288 |
+
tokenizer: Optional["PreTrainedTokenizerBase"] = None,
|
| 289 |
+
fsd_threshold: float = 0.0,
|
| 290 |
+
fsd_div_type: str = "kl",
|
| 291 |
+
**model_kwargs,
|
| 292 |
+
) -> Union[GenerateDecoderOnlyOutput, GenerateEncoderDecoderOutput, torch.LongTensor]:
|
| 293 |
+
r"""
|
| 294 |
+
Generates sequences of token ids for models with a language modeling head using **greedy decoding** or
|
| 295 |
+
**sample** (depending on `do_sample`), assisted by candidate sequences. Assisted generation is an example of a
|
| 296 |
+
candidate decoding strategy. Can be used for text-decoder, text-to-text, speech-to-text, and vision-to-text
|
| 297 |
+
models.
|
| 298 |
+
"""
|
| 299 |
+
# The cache must be dynamic for assisted generation, and the check must happen AFTER preparing cache
|
| 300 |
+
if not model_kwargs["use_cache"]:
|
| 301 |
+
raise ValueError("assisted generate requires `use_cache=True`")
|
| 302 |
+
if generation_config.cache_implementation in ["static", "hybrid", "sliding_window"] or (
|
| 303 |
+
"past_key_values" in model_kwargs
|
| 304 |
+
and hasattr(model_kwargs["past_key_values"], "layers")
|
| 305 |
+
and any(getattr(l, "is_compileable", False) for l in model_kwargs["past_key_values"].layers)
|
| 306 |
+
):
|
| 307 |
+
raise ValueError("assisted generate is not supported with Static cache classes`")
|
| 308 |
+
|
| 309 |
+
# Create custom candidate generator that supports raw logits
|
| 310 |
+
# Set output_logits based on generation_config (don't force it)
|
| 311 |
+
if assistant_model is None:
|
| 312 |
+
raise ValueError("assistant_model is required for assisted generation")
|
| 313 |
+
|
| 314 |
+
|
| 315 |
+
generation_config.output_logits = True
|
| 316 |
+
candidate_generator = RawLogitsCandidateGenerator(
|
| 317 |
+
input_ids=input_ids,
|
| 318 |
+
assistant_model=assistant_model,
|
| 319 |
+
generation_config=generation_config,
|
| 320 |
+
model_kwargs=model_kwargs,
|
| 321 |
+
inputs_tensor=inputs_tensor,
|
| 322 |
+
logits_processor=logits_processor,
|
| 323 |
+
)
|
| 324 |
+
# init values
|
| 325 |
+
do_sample = generation_config.do_sample
|
| 326 |
+
output_attentions = generation_config.output_attentions
|
| 327 |
+
output_hidden_states = generation_config.output_hidden_states
|
| 328 |
+
output_scores = generation_config.output_scores
|
| 329 |
+
output_logits = generation_config.output_logits
|
| 330 |
+
return_dict_in_generate = generation_config.return_dict_in_generate
|
| 331 |
+
|
| 332 |
+
# init attention / hidden states / scores tuples
|
| 333 |
+
scores = () if (return_dict_in_generate and output_scores) else None
|
| 334 |
+
raw_logits = () if (return_dict_in_generate and output_logits) else None
|
| 335 |
+
decoder_attentions = () if (return_dict_in_generate and output_attentions) else None
|
| 336 |
+
cross_attentions = () if (return_dict_in_generate and output_attentions) else None
|
| 337 |
+
decoder_hidden_states = () if (return_dict_in_generate and output_hidden_states) else None
|
| 338 |
+
|
| 339 |
+
# if model is an encoder-decoder, retrieve encoder attention weights and hidden states
|
| 340 |
+
if return_dict_in_generate and model.config.is_encoder_decoder:
|
| 341 |
+
encoder_attentions = model_kwargs["encoder_outputs"].get("attentions") if output_attentions else None
|
| 342 |
+
encoder_hidden_states = (
|
| 343 |
+
model_kwargs["encoder_outputs"].get("hidden_states") if output_hidden_states else None
|
| 344 |
+
)
|
| 345 |
+
|
| 346 |
+
# keep track of which sequences are already finished
|
| 347 |
+
batch_size, cur_len = input_ids.shape[:2]
|
| 348 |
+
if batch_size > 1:
|
| 349 |
+
raise ValueError("assisted generate is only supported for batch_size = 1")
|
| 350 |
+
unfinished_sequences = torch.ones(batch_size, dtype=torch.long, device=input_ids.device)
|
| 351 |
+
model_kwargs = model._get_initial_cache_position(cur_len, input_ids.device, model_kwargs)
|
| 352 |
+
|
| 353 |
+
this_peer_finished = False
|
| 354 |
+
is_first_iteration = True # to preserve the same API in the output as other generation methods
|
| 355 |
+
while model._has_unfinished_sequences(this_peer_finished, synced_gpus, device=input_ids.device):
|
| 356 |
+
cur_len = input_ids.shape[1]
|
| 357 |
+
|
| 358 |
+
# 1. Fetch candidate sequences from a `CandidateGenerator` and move to the correct device
|
| 359 |
+
candidate_input_ids, candidate_logits, candidate_logits_raw = candidate_generator.get_candidates(input_ids)
|
| 360 |
+
candidate_input_ids = candidate_input_ids.to(model.device)
|
| 361 |
+
if candidate_logits is not None:
|
| 362 |
+
candidate_logits = candidate_logits.to(model.device)
|
| 363 |
+
if candidate_logits_raw is not None:
|
| 364 |
+
candidate_logits_raw = candidate_logits_raw.to(model.device)
|
| 365 |
+
|
| 366 |
+
candidate_length = candidate_input_ids.shape[1] - input_ids.shape[1]
|
| 367 |
+
is_done_candidate = stopping_criteria(candidate_input_ids, None)
|
| 368 |
+
|
| 369 |
+
# 2. Use the original model to obtain the next token logits given the candidate sequence. We obtain
|
| 370 |
+
# `candidate_length + 1` relevant logits from this process: in the event that all candidates are correct,
|
| 371 |
+
# we use this forward pass to also pick the subsequent logits in the original model.
|
| 372 |
+
|
| 373 |
+
# 2.1. Prepare the model inputs
|
| 374 |
+
candidate_kwargs = copy.copy(model_kwargs)
|
| 375 |
+
candidate_kwargs = _prepare_attention_mask(
|
| 376 |
+
candidate_kwargs, candidate_input_ids.shape[1], model.config.is_encoder_decoder
|
| 377 |
+
)
|
| 378 |
+
candidate_kwargs = _prepare_token_type_ids(candidate_kwargs, candidate_input_ids.shape[1])
|
| 379 |
+
if "cache_position" in candidate_kwargs:
|
| 380 |
+
candidate_kwargs["cache_position"] = torch.cat(
|
| 381 |
+
(
|
| 382 |
+
candidate_kwargs["cache_position"],
|
| 383 |
+
torch.arange(cur_len, cur_len + candidate_length, device=input_ids.device, dtype=torch.long),
|
| 384 |
+
),
|
| 385 |
+
dim=0,
|
| 386 |
+
)
|
| 387 |
+
|
| 388 |
+
model_inputs = model.prepare_inputs_for_generation(candidate_input_ids, **candidate_kwargs)
|
| 389 |
+
if "logits_to_keep" in model_inputs:
|
| 390 |
+
model_inputs["logits_to_keep"] = candidate_length + 1
|
| 391 |
+
|
| 392 |
+
# 2.2. Run a forward pass on the candidate sequence
|
| 393 |
+
outputs = model(**model_inputs)
|
| 394 |
+
|
| 395 |
+
# 2.3. Process the new logits
|
| 396 |
+
# .float() is needed to retain precision for later logits manipulations
|
| 397 |
+
new_logits = outputs.logits[:, -candidate_length - 1 :].to(
|
| 398 |
+
dtype=torch.float32, device=input_ids.device
|
| 399 |
+
) # excludes the input prompt if present
|
| 400 |
+
next_token_logits = new_logits.clone()
|
| 401 |
+
if len(logits_processor) > 0:
|
| 402 |
+
for i in range(candidate_length + 1):
|
| 403 |
+
new_logits[:, i, :] = logits_processor(candidate_input_ids[:, : cur_len + i], new_logits[:, i, :])
|
| 404 |
+
|
| 405 |
+
# 3. Select the accepted tokens. There are two possible cases:
|
| 406 |
+
# Case 1: `do_sample=True` and we have logits for the candidates (originally from speculative decoding)
|
| 407 |
+
# 👉 Apply algorithm 1 from the speculative decoding paper (https://huggingface.co/papers/2211.17192).
|
| 408 |
+
if do_sample and candidate_logits is not None:
|
| 409 |
+
valid_tokens, n_matches = _speculative_sampling(
|
| 410 |
+
candidate_input_ids,
|
| 411 |
+
candidate_logits,
|
| 412 |
+
candidate_length,
|
| 413 |
+
new_logits,
|
| 414 |
+
next_token_logits,
|
| 415 |
+
is_done_candidate,
|
| 416 |
+
candidate_logits_raw=candidate_logits_raw,
|
| 417 |
+
fsd_threshold=fsd_threshold,
|
| 418 |
+
fsd_div_type=fsd_div_type,
|
| 419 |
+
)
|
| 420 |
+
|
| 421 |
+
# Case 2: all other cases (originally from assisted generation) 👉 Compare the tokens selected from the
|
| 422 |
+
# original model logits with the candidate tokens. We can keep the candidate tokens until the first
|
| 423 |
+
# mismatch, or until the max length is reached.
|
| 424 |
+
else:
|
| 425 |
+
if do_sample:
|
| 426 |
+
probs = new_logits.softmax(dim=-1)
|
| 427 |
+
selected_tokens = torch.multinomial(probs[0, :, :], num_samples=1).squeeze(1)[None, :]
|
| 428 |
+
else:
|
| 429 |
+
selected_tokens = new_logits.argmax(dim=-1)
|
| 430 |
+
|
| 431 |
+
candidate_new_tokens = candidate_input_ids[:, cur_len:]
|
| 432 |
+
n_matches = ((~(candidate_new_tokens == selected_tokens[:, :-1])).cumsum(dim=-1) < 1).sum()
|
| 433 |
+
|
| 434 |
+
# Ensure we don't generate beyond max_len or an EOS token
|
| 435 |
+
if is_done_candidate and n_matches == candidate_length:
|
| 436 |
+
n_matches -= 1
|
| 437 |
+
valid_tokens = selected_tokens[:, : n_matches + 1]
|
| 438 |
+
|
| 439 |
+
# 4. Update variables according to the number of matching assistant tokens. Remember: the token generated
|
| 440 |
+
# by the model after the last candidate match is also valid, as it is generated from a correct sequence.
|
| 441 |
+
# Because of this last token, assisted generation search reduces to a normal greedy search/sample if there
|
| 442 |
+
# is no match.
|
| 443 |
+
|
| 444 |
+
# 4.1. Get the valid continuation, after the matching tokens
|
| 445 |
+
input_ids = torch.cat((input_ids, valid_tokens), dim=-1)
|
| 446 |
+
if streamer is not None:
|
| 447 |
+
streamer.put(valid_tokens.cpu())
|
| 448 |
+
new_cur_len = input_ids.shape[1]
|
| 449 |
+
|
| 450 |
+
# 4.2. Discard past key values relative to unused assistant tokens
|
| 451 |
+
outputs.past_key_values.crop(new_cur_len - 1)
|
| 452 |
+
|
| 453 |
+
# 5. Update the candidate generation strategy if needed
|
| 454 |
+
candidate_generator.update_candidate_strategy(input_ids, new_logits, n_matches)
|
| 455 |
+
|
| 456 |
+
# synced_gpus: don't waste resources running the code we don't need; kwargs must be updated before skipping
|
| 457 |
+
model_kwargs = model._update_model_kwargs_for_generation(
|
| 458 |
+
outputs,
|
| 459 |
+
model_kwargs,
|
| 460 |
+
is_encoder_decoder=model.config.is_encoder_decoder,
|
| 461 |
+
num_new_tokens=n_matches + 1,
|
| 462 |
+
)
|
| 463 |
+
if synced_gpus and this_peer_finished:
|
| 464 |
+
continue
|
| 465 |
+
|
| 466 |
+
# Store scores, attentions and hidden_states when required
|
| 467 |
+
# Assistant: modified to append one tuple element per token, as in the other generation methods.
|
| 468 |
+
if return_dict_in_generate:
|
| 469 |
+
newly_added_length = n_matches + 1
|
| 470 |
+
if output_scores:
|
| 471 |
+
scores += tuple(new_logits[:, i, :] for i in range(newly_added_length))
|
| 472 |
+
if output_logits:
|
| 473 |
+
raw_logits += tuple(next_token_logits[:, i, :] for i in range(newly_added_length))
|
| 474 |
+
|
| 475 |
+
newly_added_length = new_cur_len if is_first_iteration else newly_added_length
|
| 476 |
+
if output_attentions:
|
| 477 |
+
if model.config.is_encoder_decoder:
|
| 478 |
+
cross_attentions = _split_model_outputs(
|
| 479 |
+
cross_attentions, outputs.cross_attentions, cur_len, newly_added_length
|
| 480 |
+
)
|
| 481 |
+
decoder_attentions = _split_model_outputs(
|
| 482 |
+
decoder_attentions,
|
| 483 |
+
outputs.decoder_attentions,
|
| 484 |
+
cur_len,
|
| 485 |
+
newly_added_length,
|
| 486 |
+
is_decoder_attention=True,
|
| 487 |
+
)
|
| 488 |
+
# some (V)LLMs have hard requirement on SDPA and thus never return attn
|
| 489 |
+
elif outputs.attentions[0] is not None:
|
| 490 |
+
decoder_attentions = _split_model_outputs(
|
| 491 |
+
decoder_attentions,
|
| 492 |
+
outputs.attentions,
|
| 493 |
+
cur_len,
|
| 494 |
+
newly_added_length,
|
| 495 |
+
is_decoder_attention=True,
|
| 496 |
+
)
|
| 497 |
+
if output_hidden_states:
|
| 498 |
+
if model.config.is_encoder_decoder:
|
| 499 |
+
decoder_hidden_states = _split_model_outputs(
|
| 500 |
+
decoder_hidden_states, outputs.decoder_hidden_states, cur_len, newly_added_length
|
| 501 |
+
)
|
| 502 |
+
else:
|
| 503 |
+
decoder_hidden_states = _split_model_outputs(
|
| 504 |
+
decoder_hidden_states, outputs.hidden_states, cur_len, newly_added_length
|
| 505 |
+
)
|
| 506 |
+
|
| 507 |
+
unfinished_sequences = unfinished_sequences & ~stopping_criteria(input_ids, scores)
|
| 508 |
+
this_peer_finished = unfinished_sequences.max() == 0
|
| 509 |
+
is_first_iteration = False
|
| 510 |
+
|
| 511 |
+
if streamer is not None:
|
| 512 |
+
streamer.end()
|
| 513 |
+
|
| 514 |
+
if (
|
| 515 |
+
hasattr(candidate_generator, "assistant_model")
|
| 516 |
+
and candidate_generator.assistant_model.generation_config.num_assistant_tokens_schedule == "heuristic"
|
| 517 |
+
):
|
| 518 |
+
candidate_generator.assistant_model.generation_config.num_assistant_tokens = (
|
| 519 |
+
candidate_generator.num_assistant_tokens
|
| 520 |
+
)
|
| 521 |
+
if return_dict_in_generate:
|
| 522 |
+
cache = None
|
| 523 |
+
if any(cache_key in model_kwargs for cache_key in ALL_CACHE_NAMES):
|
| 524 |
+
cache_key = next(cache_key for cache_key in ALL_CACHE_NAMES if cache_key in model_kwargs)
|
| 525 |
+
cache = model_kwargs[cache_key]
|
| 526 |
+
if model.config.is_encoder_decoder:
|
| 527 |
+
return GenerateEncoderDecoderOutput(
|
| 528 |
+
sequences=input_ids,
|
| 529 |
+
scores=scores,
|
| 530 |
+
logits=raw_logits,
|
| 531 |
+
encoder_attentions=encoder_attentions,
|
| 532 |
+
encoder_hidden_states=encoder_hidden_states,
|
| 533 |
+
decoder_attentions=decoder_attentions,
|
| 534 |
+
cross_attentions=cross_attentions,
|
| 535 |
+
decoder_hidden_states=decoder_hidden_states,
|
| 536 |
+
past_key_values=cache,
|
| 537 |
+
)
|
| 538 |
+
else:
|
| 539 |
+
return GenerateDecoderOnlyOutput(
|
| 540 |
+
sequences=input_ids,
|
| 541 |
+
scores=scores,
|
| 542 |
+
logits=raw_logits,
|
| 543 |
+
attentions=decoder_attentions,
|
| 544 |
+
hidden_states=decoder_hidden_states,
|
| 545 |
+
past_key_values=cache,
|
| 546 |
+
)
|
| 547 |
+
else:
|
| 548 |
+
return input_ids
|
| 549 |
+
|
| 550 |
+
|
| 551 |
+
def generate(
|
| 552 |
+
model,
|
| 553 |
+
inputs: torch.Tensor | None = None,
|
| 554 |
+
generation_config: GenerationConfig | None = None,
|
| 555 |
+
logits_processor: LogitsProcessorList | None = None,
|
| 556 |
+
stopping_criteria: StoppingCriteriaList | None = None,
|
| 557 |
+
prefix_allowed_tokens_fn: Callable[[int, torch.Tensor], list[int]] | None = None,
|
| 558 |
+
synced_gpus: bool | None = None,
|
| 559 |
+
assistant_model: Optional["PreTrainedModel"] = None,
|
| 560 |
+
streamer: Optional["BaseStreamer"] = None,
|
| 561 |
+
negative_prompt_ids: torch.Tensor | None = None,
|
| 562 |
+
negative_prompt_attention_mask: torch.Tensor | None = None,
|
| 563 |
+
**kwargs,
|
| 564 |
+
) -> GenerateDecoderOnlyOutput | GenerateEncoderDecoderOutput | torch.LongTensor:
|
| 565 |
+
r"""
|
| 566 |
+
Generates sequences of token ids for models with a language modeling head.
|
| 567 |
+
|
| 568 |
+
This is a custom generate function that replaces the standard one. It supports all standard generation modes
|
| 569 |
+
and includes custom speculative decoding acceptance/rejection logic.
|
| 570 |
+
"""
|
| 571 |
+
# 1. Handle kwargs, `generation_config`, validate them and obtain generation mode
|
| 572 |
+
# Extract custom parameters before validation (they're not standard generation config params)
|
| 573 |
+
fsd_threshold = kwargs.pop("fsd_threshold", 0.0)
|
| 574 |
+
fsd_div_type = kwargs.pop("fsd_div_type", "kl")
|
| 575 |
+
|
| 576 |
+
generation_mode_kwargs = model._extract_generation_mode_kwargs(
|
| 577 |
+
None, # custom_generate
|
| 578 |
+
kwargs,
|
| 579 |
+
synced_gpus,
|
| 580 |
+
assistant_model,
|
| 581 |
+
streamer,
|
| 582 |
+
)
|
| 583 |
+
# Add custom FSD parameters to generation_mode_kwargs so they're passed to _assisted_decoding
|
| 584 |
+
generation_mode_kwargs["fsd_threshold"] = fsd_threshold
|
| 585 |
+
generation_mode_kwargs["fsd_div_type"] = fsd_div_type
|
| 586 |
+
|
| 587 |
+
# Check length values before updating the config with defaults
|
| 588 |
+
has_default_max_length = kwargs.get("max_length") is None and (
|
| 589 |
+
generation_config is None or generation_config.max_length is None
|
| 590 |
+
)
|
| 591 |
+
has_default_min_length = kwargs.get("min_length") is None and (
|
| 592 |
+
generation_config is None or generation_config.min_length is None
|
| 593 |
+
)
|
| 594 |
+
generation_config, model_kwargs = model._prepare_generation_config(generation_config, **kwargs)
|
| 595 |
+
|
| 596 |
+
generation_mode = generation_config.get_generation_mode(assistant_model)
|
| 597 |
+
# type() required to access the unbound class-level method
|
| 598 |
+
decoding_method = getattr(type(model), GENERATION_MODES_MAPPING[generation_mode])
|
| 599 |
+
|
| 600 |
+
model._validate_model_kwargs(model_kwargs.copy())
|
| 601 |
+
model._validate_generation_mode(generation_mode, generation_config, generation_mode_kwargs)
|
| 602 |
+
|
| 603 |
+
# 2. Set generation parameters if not already defined
|
| 604 |
+
logits_processor = logits_processor if logits_processor is not None else LogitsProcessorList()
|
| 605 |
+
stopping_criteria = stopping_criteria if stopping_criteria is not None else StoppingCriteriaList()
|
| 606 |
+
|
| 607 |
+
accepts_attention_mask = "attention_mask" in set(inspect.signature(model.forward).parameters.keys())
|
| 608 |
+
requires_attention_mask = "encoder_outputs" not in model_kwargs
|
| 609 |
+
kwargs_has_attention_mask = model_kwargs.get("attention_mask", None) is not None
|
| 610 |
+
|
| 611 |
+
# 3. Define model inputs
|
| 612 |
+
inputs_tensor, model_input_name, model_kwargs = model._prepare_model_inputs(
|
| 613 |
+
inputs, generation_config.bos_token_id, model_kwargs
|
| 614 |
+
)
|
| 615 |
+
# Some generation modes (e.g. assisted) need `inputs_tensor` to rerun encoder.forward()
|
| 616 |
+
if "inputs_tensor" in inspect.signature(decoding_method).parameters.keys():
|
| 617 |
+
generation_mode_kwargs["inputs_tensor"] = inputs_tensor
|
| 618 |
+
batch_size = inputs_tensor.shape[0]
|
| 619 |
+
|
| 620 |
+
device = inputs_tensor.device
|
| 621 |
+
model._prepare_special_tokens(generation_config, kwargs_has_attention_mask, device=device)
|
| 622 |
+
|
| 623 |
+
# decoder-only models must use left-padding for batched generation.
|
| 624 |
+
if not model.config.is_encoder_decoder:
|
| 625 |
+
# If `input_ids` was given, check if the last id in any sequence is `pad_token_id`
|
| 626 |
+
if (
|
| 627 |
+
generation_config._pad_token_tensor is not None
|
| 628 |
+
and batch_size > 1
|
| 629 |
+
and len(inputs_tensor.shape) == 2
|
| 630 |
+
and torch.sum(inputs_tensor[:, -1] == generation_config._pad_token_tensor) > 0
|
| 631 |
+
):
|
| 632 |
+
import logging
|
| 633 |
+
logger = logging.get_logger(__name__)
|
| 634 |
+
logger.warning(
|
| 635 |
+
"A decoder-only architecture is being used, but right-padding was detected! For correct "
|
| 636 |
+
"generation results, please set `padding_side='left'` when initializing the tokenizer."
|
| 637 |
+
)
|
| 638 |
+
|
| 639 |
+
# 4. Define other model kwargs
|
| 640 |
+
# decoder-only models with inputs_embeds forwarding must use caching
|
| 641 |
+
if not model.config.is_encoder_decoder and model_input_name == "inputs_embeds":
|
| 642 |
+
generation_config.use_cache = True
|
| 643 |
+
|
| 644 |
+
if not kwargs_has_attention_mask and requires_attention_mask and accepts_attention_mask:
|
| 645 |
+
model_kwargs["attention_mask"] = model._prepare_attention_mask_for_generation(
|
| 646 |
+
inputs_tensor, generation_config, model_kwargs
|
| 647 |
+
)
|
| 648 |
+
elif kwargs_has_attention_mask:
|
| 649 |
+
# TODO (joao): generalize this check with other types of inputs
|
| 650 |
+
if model_input_name == "input_ids" and len(model_kwargs["attention_mask"].shape) > 2:
|
| 651 |
+
raise ValueError("`attention_mask` passed to `generate` must be 2D.")
|
| 652 |
+
|
| 653 |
+
if model.config.is_encoder_decoder and "encoder_outputs" not in model_kwargs:
|
| 654 |
+
# if model is encoder decoder encoder_outputs are created and added to `model_kwargs`
|
| 655 |
+
model_kwargs = model._prepare_encoder_decoder_kwargs_for_generation(
|
| 656 |
+
inputs_tensor, model_kwargs, model_input_name, generation_config
|
| 657 |
+
)
|
| 658 |
+
|
| 659 |
+
# 5. Prepare `input_ids` which will be used for auto-regressive generation
|
| 660 |
+
if model.config.is_encoder_decoder:
|
| 661 |
+
input_ids, model_kwargs = model._prepare_decoder_input_ids_for_generation(
|
| 662 |
+
batch_size=batch_size,
|
| 663 |
+
model_input_name=model_input_name,
|
| 664 |
+
model_kwargs=model_kwargs,
|
| 665 |
+
decoder_start_token_id=generation_config._decoder_start_token_tensor,
|
| 666 |
+
device=inputs_tensor.device,
|
| 667 |
+
)
|
| 668 |
+
else:
|
| 669 |
+
input_ids = inputs_tensor if model_input_name == "input_ids" else model_kwargs.pop("input_ids")
|
| 670 |
+
|
| 671 |
+
# Expand inputs depending on the generation mode
|
| 672 |
+
input_ids, model_kwargs = model._expand_inputs_for_generation(
|
| 673 |
+
input_ids=input_ids,
|
| 674 |
+
expand_size=max(generation_config.num_beams, generation_config.num_return_sequences),
|
| 675 |
+
is_encoder_decoder=model.config.is_encoder_decoder,
|
| 676 |
+
**model_kwargs,
|
| 677 |
+
)
|
| 678 |
+
|
| 679 |
+
if generation_config.token_healing:
|
| 680 |
+
input_ids = model.heal_tokens(input_ids, generation_mode_kwargs.get("tokenizer"))
|
| 681 |
+
|
| 682 |
+
if streamer is not None:
|
| 683 |
+
streamer.put(input_ids.cpu())
|
| 684 |
+
|
| 685 |
+
# 6. Prepare `max_length` depending on other stopping criteria.
|
| 686 |
+
input_ids_length = input_ids.shape[1]
|
| 687 |
+
generation_config = model._prepare_generated_length(
|
| 688 |
+
generation_config=generation_config,
|
| 689 |
+
has_default_max_length=has_default_max_length,
|
| 690 |
+
has_default_min_length=has_default_min_length,
|
| 691 |
+
model_input_name=model_input_name,
|
| 692 |
+
inputs_tensor=inputs_tensor,
|
| 693 |
+
input_ids_length=input_ids_length,
|
| 694 |
+
)
|
| 695 |
+
|
| 696 |
+
# If the model supports `logits_to_keep` in forward(), set it to 1 to avoid computing the whole
|
| 697 |
+
# logit matrix. This can save a lot of memory during the first forward pass. Note that assisted decoding
|
| 698 |
+
# dynamically overrides this value as it can need more than the last token logits
|
| 699 |
+
if model._supports_logits_to_keep() and "logits_to_keep" not in model_kwargs:
|
| 700 |
+
model_kwargs["logits_to_keep"] = 1
|
| 701 |
+
|
| 702 |
+
model._validate_generated_length(generation_config, input_ids_length, has_default_max_length)
|
| 703 |
+
|
| 704 |
+
# 7. Prepare the cache.
|
| 705 |
+
max_cache_length = generation_config.max_length - 1
|
| 706 |
+
if (
|
| 707 |
+
inputs_tensor.shape[1] != input_ids_length
|
| 708 |
+
and model_input_name == "inputs_embeds"
|
| 709 |
+
and not model.config.is_encoder_decoder
|
| 710 |
+
):
|
| 711 |
+
max_cache_length += inputs_tensor.shape[1]
|
| 712 |
+
model._prepare_cache_for_generation(
|
| 713 |
+
generation_config, model_kwargs, generation_mode, batch_size, max_cache_length
|
| 714 |
+
)
|
| 715 |
+
|
| 716 |
+
if model.device.type != input_ids.device.type:
|
| 717 |
+
warnings.warn(
|
| 718 |
+
"You are calling .generate() with the `input_ids` being on a device type different"
|
| 719 |
+
f" than your model's device. `input_ids` is on {input_ids.device.type}, whereas the model"
|
| 720 |
+
f" is on {model.device.type}. You may experience unexpected behaviors or slower generation."
|
| 721 |
+
" Please make sure that you have put `input_ids` to the"
|
| 722 |
+
f" correct device by calling for example input_ids = input_ids.to('{model.device.type}') before"
|
| 723 |
+
" running `.generate()`.",
|
| 724 |
+
UserWarning,
|
| 725 |
+
)
|
| 726 |
+
|
| 727 |
+
# 8. Prepare logits processors and stopping criteria
|
| 728 |
+
prepared_logits_processor = model._get_logits_processor(
|
| 729 |
+
generation_config=generation_config,
|
| 730 |
+
input_ids_seq_length=input_ids_length,
|
| 731 |
+
encoder_input_ids=inputs_tensor,
|
| 732 |
+
prefix_allowed_tokens_fn=prefix_allowed_tokens_fn,
|
| 733 |
+
logits_processor=logits_processor,
|
| 734 |
+
device=inputs_tensor.device,
|
| 735 |
+
model_kwargs=model_kwargs,
|
| 736 |
+
negative_prompt_ids=negative_prompt_ids,
|
| 737 |
+
negative_prompt_attention_mask=negative_prompt_attention_mask,
|
| 738 |
+
)
|
| 739 |
+
prepared_stopping_criteria = model._get_stopping_criteria(
|
| 740 |
+
generation_config=generation_config,
|
| 741 |
+
stopping_criteria=stopping_criteria,
|
| 742 |
+
tokenizer=generation_mode_kwargs.get("tokenizer"),
|
| 743 |
+
)
|
| 744 |
+
|
| 745 |
+
# Set model_kwargs `use_cache` so we can use it later in forward runs
|
| 746 |
+
model_kwargs["use_cache"] = generation_config.use_cache
|
| 747 |
+
|
| 748 |
+
# 9. Call generation mode
|
| 749 |
+
# For assisted generation, use our custom function
|
| 750 |
+
if generation_mode == GenerationMode.ASSISTED_GENERATION:
|
| 751 |
+
result = _assisted_decoding(
|
| 752 |
+
model,
|
| 753 |
+
input_ids,
|
| 754 |
+
logits_processor=prepared_logits_processor,
|
| 755 |
+
stopping_criteria=prepared_stopping_criteria,
|
| 756 |
+
generation_config=generation_config,
|
| 757 |
+
**generation_mode_kwargs,
|
| 758 |
+
**model_kwargs,
|
| 759 |
+
)
|
| 760 |
+
else:
|
| 761 |
+
# For other modes, use the model's standard methods
|
| 762 |
+
result = decoding_method(
|
| 763 |
+
model,
|
| 764 |
+
input_ids,
|
| 765 |
+
logits_processor=prepared_logits_processor,
|
| 766 |
+
stopping_criteria=prepared_stopping_criteria,
|
| 767 |
+
generation_config=generation_config,
|
| 768 |
+
**generation_mode_kwargs,
|
| 769 |
+
**model_kwargs,
|
| 770 |
+
)
|
| 771 |
+
|
| 772 |
+
return result
|
| 773 |
+
|
| 774 |
+
|
| 775 |
+
# def _speculative_backoff_sampling(
|
| 776 |
+
# candidate_input_ids,
|
| 777 |
+
# candidate_logits,
|
| 778 |
+
# candidate_logits_unprocessed,
|
| 779 |
+
# eos_position_logits,
|
| 780 |
+
# candidate_length,
|
| 781 |
+
# new_logits,
|
| 782 |
+
# new_logits_unprocessed,# NOTE: these are unprocessed, unwarped logits
|
| 783 |
+
# is_done_candidate,
|
| 784 |
+
# div_threshold,
|
| 785 |
+
# div_type,
|
| 786 |
+
# do_sample, # this is also passed in new
|
| 787 |
+
# logits_processor: LogitsProcessorList, # these two must be passed in because we want to work with the logits before they are processed and warped
|
| 788 |
+
# logits_warper: Optional[LogitsProcessorList], # these two must be passed in because we want to work with the logits before they are processed and warped
|
| 789 |
+
# div_logits_processor: Optional[LogitsProcessorList],
|
| 790 |
+
# cur_len,
|
| 791 |
+
# eos_token_id,
|
| 792 |
+
# candidate_generator_type='classifier',
|
| 793 |
+
# ):
|
| 794 |
+
# # valid_tokens, n_matches, new_logits = _speculative_backoff_sampling(
|
| 795 |
+
# # candidate_input_ids,
|
| 796 |
+
# # candidate_logits,
|
| 797 |
+
# # candidate_logits_unprocessed,
|
| 798 |
+
# # candidate_length,
|
| 799 |
+
# # new_logits,
|
| 800 |
+
# # is_done_candidate,
|
| 801 |
+
# # kl_div_threshold,
|
| 802 |
+
# # do_sample,
|
| 803 |
+
# # logits_processor,
|
| 804 |
+
# # logits_warper,
|
| 805 |
+
# # cur_len,
|
| 806 |
+
# # )
|
| 807 |
+
# """
|
| 808 |
+
# Applies sampling as in the speculative decoding paper (https://arxiv.org/pdf/2211.17192.pdf, algorithm 1). Returns
|
| 809 |
+
# the selected tokens, as well as the number of candidate matches.
|
| 810 |
+
|
| 811 |
+
# NOTE: Unless otherwise stated, the variable names match those in the paper.
|
| 812 |
+
# """
|
| 813 |
+
|
| 814 |
+
# '''
|
| 815 |
+
# NOTE: Implementation plan -
|
| 816 |
+
# 1. implement custom assistent model class with classifier that terminates generation as soon as last generated logit is predicted to exceed distribution
|
| 817 |
+
# Is there an issue with using EOS token to terminate sequence? since large model will simply reject this token once it checks.
|
| 818 |
+
# I think this would work, since we can then use distribution generated by large model to generate next token (the position deemed as large model-necessary by classifier)
|
| 819 |
+
# 2. implement custom candidate_generator that uses this model to generate a series of candidates - DONE (other than question about do_sample - will set to sample for now)
|
| 820 |
+
|
| 821 |
+
# 3. implement this speculative_backoff_sampling class to backtrack, checking all candidates to see if they exceed the threshold. If they do, sample from large_model logits at this position (have to adjust logits as would is regular sampling)
|
| 822 |
+
# Need to make sure logit processing and warping is correct - both in terms of warping before calling this function (so that M_L sampling is correct) and in terms of having the warping not throw of the Kl divergence calculation
|
| 823 |
+
# Probably will pass original + processed logits into speculative_backoff_decoding function
|
| 824 |
+
# 4. Update cache of both assistant and target model to discard all KV values past first rejected token using cache.crop()
|
| 825 |
+
# 5. Make sure this is properly implemented within a loop, such that following all this candidate_generator is called again to generate the next batch of tokens
|
| 826 |
+
|
| 827 |
+
# '''
|
| 828 |
+
|
| 829 |
+
# initial_start_time = time.time()
|
| 830 |
+
# new_candidate_input_ids = candidate_input_ids[:, -candidate_length:]
|
| 831 |
+
# correction_term = 0
|
| 832 |
+
|
| 833 |
+
# if div_type != 'sd':
|
| 834 |
+
|
| 835 |
+
# if div_type == 'kl_div_processed' or div_type == 'js_div_processed' or div_type == 'tv_div_processed':
|
| 836 |
+
# epsilon = 1e-10
|
| 837 |
+
# q = candidate_logits.softmax(dim=-1)
|
| 838 |
+
# p = new_logits[:, :candidate_length, :].softmax(dim=-1) # need to be cropped because M_L logits include logits for ungenerated position
|
| 839 |
+
|
| 840 |
+
# q_nonzero = (p > 0).int()
|
| 841 |
+
# p_nonzero = (q > 0).int()
|
| 842 |
+
# both_nonzero = (q_nonzero & p_nonzero).int()
|
| 843 |
+
|
| 844 |
+
# # print(f"nonzero q: {q_nonzero.sum(dim=-1)}")
|
| 845 |
+
# # print(f"nonzero p: {p_nonzero.sum(dim=-1)}")
|
| 846 |
+
# # print(f"both nonzero: {both_nonzero.sum(dim=-1)}")
|
| 847 |
+
|
| 848 |
+
# q = q + epsilon
|
| 849 |
+
# p = p + epsilon
|
| 850 |
+
|
| 851 |
+
# p = p / p.sum(dim=-1, keepdim=True)
|
| 852 |
+
# q = q / q.sum(dim=-1, keepdim=True)
|
| 853 |
+
|
| 854 |
+
|
| 855 |
+
# else:
|
| 856 |
+
# q = candidate_logits_unprocessed.softmax(dim=-1)
|
| 857 |
+
# p = new_logits_unprocessed[:, :candidate_length, :].softmax(dim=-1) # need to be cropped because M_L logits include logits for ungenerated position
|
| 858 |
+
|
| 859 |
+
# if len(div_logits_processor) > 0:
|
| 860 |
+
# epsilon = 1e-10
|
| 861 |
+
# q = q + epsilon
|
| 862 |
+
# p = p + epsilon
|
| 863 |
+
|
| 864 |
+
# p = p / p.sum(dim=-1, keepdim=True)
|
| 865 |
+
# q = q / q.sum(dim=-1, keepdim=True)
|
| 866 |
+
|
| 867 |
+
# if div_type == 'kl_div' or div_type == 'kl_div_processed':
|
| 868 |
+
# divs = torch.nn.functional.kl_div(torch.log(p), q, reduction='none').sum(dim=-1) # shape = [bs, seq_len]
|
| 869 |
+
# elif div_type == 'kl_div_reversed' or div_type == 'kl_div_reversed_processed':
|
| 870 |
+
# divs = torch.nn.functional.kl_div(torch.log(q), p, reduction='none').sum(dim=-1) # shape = [bs, seq_len]
|
| 871 |
+
# elif div_type == 'js_div' or div_type == 'js_div_processed':
|
| 872 |
+
# m = 0.5 * (p + q) # Midpoint distribution
|
| 873 |
+
# divs = (0.5 * torch.nn.functional.kl_div(torch.log(p), m, reduction='none') + 0.5 * torch.nn.functional.kl_div(torch.log(q), m, reduction='none')).sum(dim=-1)
|
| 874 |
+
# elif div_type == 'tv_div' or div_type == 'tv_div_processed':
|
| 875 |
+
# divs = 0.5 * torch.abs(p - q).sum(dim=-1)
|
| 876 |
+
|
| 877 |
+
# elif div_type == 'top_p_kl_div' or div_type == 'top_p_js_div' or div_type == 'top_p_tv_div':
|
| 878 |
+
# p_sorted, p_sorted_indexes = torch.sort(p, descending=True)
|
| 879 |
+
# q_sorted = q[p_sorted_indexes]
|
| 880 |
+
|
| 881 |
+
# cum_p = torch.cumsum(p_sorted, dim=-1)
|
| 882 |
+
|
| 883 |
+
# # Identify the top-p (nucleus) indices
|
| 884 |
+
# top_p_mask = cum_p <= top_val
|
| 885 |
+
# top_p_mask[torch.argmax(cum_p > top_val)] = True # Include the first value exceeding p
|
| 886 |
+
# top_p = p_sorted[top_p_mask]
|
| 887 |
+
# top_q = q_sorted[top_p_mask]
|
| 888 |
+
|
| 889 |
+
# # Normalize the nucleus probabilities
|
| 890 |
+
# top_p = top_p / top_p.sum()
|
| 891 |
+
# top_q = top_q / top_q.sum()
|
| 892 |
+
|
| 893 |
+
# if div_type == 'top_p_kl_div':
|
| 894 |
+
# divs = torch.nn.functional.kl_div(torch.log(top_p), top_q, reduction='none').sum(dim=-1)
|
| 895 |
+
|
| 896 |
+
# if div_type == 'top_p_js_div':
|
| 897 |
+
# m = 0.5 * (top_p + top_q) # Midpoint distribution
|
| 898 |
+
# divs = (0.5 * torch.nn.functional.kl_div(torch.log(top_p), m, reduction='none') + 0.5 * torch.nn.functional.kl_div(torch.log(top_q), m, reduction='none')).sum(dim=-1)
|
| 899 |
+
|
| 900 |
+
# if div_type == 'top_p_tv_div':
|
| 901 |
+
# divs = 0.5 * torch.abs(top_p - top_q).sum(dim=-1)
|
| 902 |
+
|
| 903 |
+
# elif div_type == 'top_k_kl_div' or div_type == 'top_k_js_div' or div_type == 'top_k_tv_div':
|
| 904 |
+
# top_val = 50
|
| 905 |
+
|
| 906 |
+
# # print(f"p distr: {p}")
|
| 907 |
+
# # print(f"q distr: {q}")
|
| 908 |
+
|
| 909 |
+
# p_top_k, p_top_k_indices = torch.topk(p, top_val, dim=-1)
|
| 910 |
+
# q_top_k = torch.gather(q, -1, p_top_k_indices)
|
| 911 |
+
|
| 912 |
+
# top_k_mask = torch.zeros_like(p, dtype=torch.bool).scatter_(-1, p_top_k_indices, True)
|
| 913 |
+
|
| 914 |
+
# non_top_k_mask = ~top_k_mask # Invert the mask
|
| 915 |
+
# p_non_top_k_values = p * non_top_k_mask # Zero out the top_k values
|
| 916 |
+
# q_non_top_k_values = q * non_top_k_mask # Zero out the top_k values
|
| 917 |
+
|
| 918 |
+
# # Sum over the non-top_k positions
|
| 919 |
+
# p_non_top_k_sum = p_non_top_k_values.sum(dim=-1, keepdim=True)
|
| 920 |
+
# q_non_top_k_sum = q_non_top_k_values.sum(dim=-1, keepdim=True)
|
| 921 |
+
# # print(f"p_non_top_k_sum: {p_non_top_k_sum}")
|
| 922 |
+
|
| 923 |
+
# # p_non_top_k_sum = 1 - p_top_k.sum(dim=-1, keepdim=True)
|
| 924 |
+
# # q_non_top_k_sum = 1 - q_top_k.sum(dim=-1, keepdim=True)
|
| 925 |
+
|
| 926 |
+
# p_top_k = torch.cat((p_top_k, p_non_top_k_sum), dim=-1)
|
| 927 |
+
# q_top_k = torch.cat((q_top_k, q_non_top_k_sum), dim=-1)
|
| 928 |
+
|
| 929 |
+
# # print(f"p_top_k.shape: {p_top_k.shape}")
|
| 930 |
+
# # print(f"q_top_k.shape: {q_top_k.shape}")
|
| 931 |
+
|
| 932 |
+
# # p_top_k, p_top_k_indices = torch.topk(p, top_val, dim=-1)
|
| 933 |
+
# # q_top_k = q[:, :, p_top_k_indices]
|
| 934 |
+
|
| 935 |
+
# if div_type == 'top_k_kl_div':
|
| 936 |
+
# divs = torch.nn.functional.kl_div(torch.log(p_top_k), q_top_k, reduction='none').sum(dim=-1)
|
| 937 |
+
|
| 938 |
+
# if div_type == 'top_k_js_div':
|
| 939 |
+
# m = 0.5 * (p_top_k + q_top_k) # Midpoint distribution
|
| 940 |
+
# divs = (0.5 * torch.nn.functional.kl_div(torch.log(p_top_k), m, reduction='none') + 0.5 * torch.nn.functional.kl_div(torch.log(q_top_k), m, reduction='none')).sum(dim=-1)
|
| 941 |
+
|
| 942 |
+
# if div_type == 'top_k_tv_div':
|
| 943 |
+
# divs = 0.5 * torch.abs(p_top_k - q_top_k).sum(dim=-1)
|
| 944 |
+
|
| 945 |
+
# print(f"divs: {divs}")
|
| 946 |
+
|
| 947 |
+
# is_accepted = divs <= div_threshold
|
| 948 |
+
|
| 949 |
+
|
| 950 |
+
# print(f"divs: {divs.tolist()} threshold: {div_threshold} div_type: {div_type}")
|
| 951 |
+
|
| 952 |
+
# else:
|
| 953 |
+
# q = candidate_logits_unprocessed.softmax(dim=-1) # depends on whether processing candidate_logits or not
|
| 954 |
+
# q_i = q[:, torch.arange(candidate_length), new_candidate_input_ids].squeeze(0, 1)
|
| 955 |
+
# p = new_logits.softmax(dim=-1)
|
| 956 |
+
# p_i = p[:, torch.arange(candidate_length), new_candidate_input_ids].squeeze(0, 1)
|
| 957 |
+
# # print(f"SD in SBD - q: {q}, \np: {p}")
|
| 958 |
+
# probability_ratio = p_i / q_i
|
| 959 |
+
|
| 960 |
+
# # When probability_ratio > 1 (i.e. q_i(x) < p_i(x), or "assistant probability of the candidate token is smaller
|
| 961 |
+
# # than the model probability for the same token"), keep the token. Otherwise reject with p = 1 - probability_ratio
|
| 962 |
+
# # (= keep with p = probability_ratio). Keep all the tokens until the first rejection
|
| 963 |
+
# r_i = torch.rand_like(probability_ratio)
|
| 964 |
+
# divs = r_i
|
| 965 |
+
# is_accepted = r_i <= probability_ratio
|
| 966 |
+
|
| 967 |
+
# # print(f"kl_div: {kl_div_threshold}")
|
| 968 |
+
# acceptance_time = time.time() - initial_start_time
|
| 969 |
+
# start_time = time.time()
|
| 970 |
+
# # print(f"acceptance time: {acceptance_time}")
|
| 971 |
+
# # print(f"divs: {divs}")
|
| 972 |
+
|
| 973 |
+
# # true_kl_divs = kl_divs.clone()
|
| 974 |
+
# if eos_position_logits != None:
|
| 975 |
+
# true_divs = divs.clone()
|
| 976 |
+
# eos_position_probs = eos_position_logits.softmax(dim=-1)
|
| 977 |
+
# eos_position_div = torch.nn.functional.kl_div(torch.log(p[:, -1, :].unsqueeze(1)), eos_position_probs, reduction='none').sum(dim=-1)
|
| 978 |
+
# true_divs[:, -1] = eos_position_div
|
| 979 |
+
# else:
|
| 980 |
+
# true_divs = divs
|
| 981 |
+
|
| 982 |
+
# # print(f"divs: {true_divs.tolist()}")
|
| 983 |
+
# # print(f"div_threshold: {div_threshold}")
|
| 984 |
+
|
| 985 |
+
# # labels = (kl_divs <= kl_div_threshold).int()
|
| 986 |
+
|
| 987 |
+
# n_matches = ((~is_accepted).cumsum(dim=-1) < 1).sum() # this is `n` in algorithm 1 -
|
| 988 |
+
# # Process and warp the logits before sampling
|
| 989 |
+
# # if len(logits_processor) > 0:
|
| 990 |
+
# # for i in range(n_matches + 1):
|
| 991 |
+
# # new_logits[:, i, :] = logits_processor(candidate_input_ids[:, : cur_len + i], new_logits[:, i, :])
|
| 992 |
+
# # if do_sample and len(logits_warper) > 0:
|
| 993 |
+
# # for i in range(n_matches + 1):
|
| 994 |
+
# # new_logits[:, i, :] = logits_warper(candidate_input_ids[:, : cur_len + i], new_logits[:, i, :])
|
| 995 |
+
# logit_processing_time = time.time() - start_time
|
| 996 |
+
# start_time = time.time()
|
| 997 |
+
# # print(f"new_logits shape inside: {new_logits.shape}")
|
| 998 |
+
# # print(f"logit_processing_time: {logit_processing_time}")
|
| 999 |
+
# # print(f"candidate_generator_type: {candidate_generator_type}")
|
| 1000 |
+
|
| 1001 |
+
# if candidate_length == n_matches and new_candidate_input_ids[0, -1] == eos_token_id and candidate_generator_type != 'regular' and div_type != 'sd':
|
| 1002 |
+
# # print(f"Accepted an eos_token")
|
| 1003 |
+
# is_done_candidate = True
|
| 1004 |
+
|
| 1005 |
+
# is_done_time = time.time() - start_time
|
| 1006 |
+
# start_time = time.time()
|
| 1007 |
+
# # print(f"is_done_time: {is_done_time}")
|
| 1008 |
+
# if is_done_candidate and n_matches == candidate_length:
|
| 1009 |
+
# backoff_count = n_matches
|
| 1010 |
+
# total = candidate_length
|
| 1011 |
+
# n_matches -= 1
|
| 1012 |
+
# correction_term = 1
|
| 1013 |
+
# valid_tokens = new_candidate_input_ids[:, : n_matches + 1]
|
| 1014 |
+
|
| 1015 |
+
# else:
|
| 1016 |
+
# if div_type != 'sd':
|
| 1017 |
+
# p_n_plus_1 = new_logits.softmax(dim=-1)[:, n_matches, :] # need to reuse new_logits because want to do post processing
|
| 1018 |
+
# p_prime = p_n_plus_1 # this is the distribution at the position we must sample from to replace the first rejection
|
| 1019 |
+
|
| 1020 |
+
# # token selection
|
| 1021 |
+
# if do_sample:
|
| 1022 |
+
# next_tokens = torch.multinomial(p_prime, num_samples=1)# .squeeze(1) # check that distributions are adjusted accordingly before being passed into this.
|
| 1023 |
+
# else:
|
| 1024 |
+
# next_tokens = torch.argmax(p_prime, dim=-1)
|
| 1025 |
+
# # The selected tokens include the matches (if any) plus the next sampled tokens
|
| 1026 |
+
# if n_matches > 0:
|
| 1027 |
+
# valid_tokens = torch.cat((new_candidate_input_ids[:, :n_matches], next_tokens), dim=-1)
|
| 1028 |
+
# else:
|
| 1029 |
+
# valid_tokens = next_tokens
|
| 1030 |
+
# else:
|
| 1031 |
+
# gamma = candidate_logits.shape[1]
|
| 1032 |
+
# p_n_plus_1 = p[:, n_matches, :]
|
| 1033 |
+
# if n_matches < gamma:
|
| 1034 |
+
# q_n_plus_1 = q[:, n_matches, :]
|
| 1035 |
+
# p_prime = torch.clamp((p_n_plus_1 - q_n_plus_1), min=0)
|
| 1036 |
+
# p_prime.div_(p_prime.sum())
|
| 1037 |
+
# else:
|
| 1038 |
+
# p_prime = p_n_plus_1
|
| 1039 |
+
# # print(f"p_prime: {p_prime}")
|
| 1040 |
+
# t = torch.multinomial(p_prime, num_samples=1).squeeze(1)[None, :]
|
| 1041 |
+
|
| 1042 |
+
# # The selected tokens include the matches (if any) plus the next sampled tokens
|
| 1043 |
+
# if n_matches > 0:
|
| 1044 |
+
# valid_tokens = torch.cat((new_candidate_input_ids[:, :n_matches], t), dim=-1)
|
| 1045 |
+
# else:
|
| 1046 |
+
# valid_tokens = t
|
| 1047 |
+
|
| 1048 |
+
# print(f"SBD: candidate_length: {candidate_length}, n_matches: {n_matches}")
|
| 1049 |
+
# # if candidate_length != 5:
|
| 1050 |
+
# # print(f"prediction: {true_divs[:, -1].item() > div_threshold}")
|
| 1051 |
+
# # spec_sampling_time = (time.time() - start_time) + acceptance_time
|
| 1052 |
+
# spec_sampling_time = time.time() - start_time
|
| 1053 |
+
# # print(f"spec_sampling_time: {spec_sampling_time}")
|
| 1054 |
+
# total_time = time.time() - initial_start_time
|
| 1055 |
+
# # print(f"total_time: {total_time} == {acceptance_time + logit_processing_time + is_done_time + spec_sampling_time}")
|
| 1056 |
+
# # print(f"total_time without processing: {total_time - logit_processing_time}")
|
| 1057 |
+
# return valid_tokens, n_matches, new_logits, correction_term, true_divs, acceptance_time, spec_sampling_time
|
custom_generate/requirements.txt
ADDED
|
@@ -0,0 +1,3 @@
|
|
|
|
|
|
|
|
|
|
|
|
|
| 1 |
+
torch>=2.0.0
|
| 2 |
+
transformers>=4.40.0
|
| 3 |
+
|