koboldcpp/conversion/gpt2.py
Piotr Wilkin (ilintar) cc7200bf12
Refactor: convert_hf_to_gguf.py (#17114)
* move conversion code to a dedicated conversion directory and split the files akin to the src/models architecture

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Co-authored-by: Sigbjørn Skjæret <sigbjorn.skjaeret@scala.com>
2026-05-15 15:18:12 +02:00

78 lines
3.2 KiB
Python

from __future__ import annotations
from typing import Iterable, TYPE_CHECKING
import torch
if TYPE_CHECKING:
from torch import Tensor
from .base import ModelBase, TextModel, gguf, logger
@ModelBase.register("GPT2LMHeadModel")
class GPT2Model(TextModel):
model_arch = gguf.MODEL_ARCH.GPT2
def set_gguf_parameters(self):
self.gguf_writer.add_block_count(self.block_count)
self.gguf_writer.add_context_length(self.hparams["n_ctx"])
self.gguf_writer.add_embedding_length(self.hparams["n_embd"])
self.gguf_writer.add_feed_forward_length(4 * self.hparams["n_embd"])
self.gguf_writer.add_head_count(self.hparams["n_head"])
self.gguf_writer.add_layer_norm_eps(self.hparams["layer_norm_epsilon"])
self.gguf_writer.add_file_type(self.ftype)
def modify_tensors(self, data_torch: Tensor, name: str, bid: int | None) -> Iterable[tuple[str, Tensor]]:
# we don't need these
if name.endswith((".attn.bias", ".attn.masked_bias")):
yield from super().modify_tensors(data_torch, name, bid)
return
if name.endswith((".c_attn.weight", ".c_proj.weight", ".c_fc.weight", ".c_proj.weight")):
data_torch = data_torch.transpose(1, 0)
new_name = self.map_tensor_name(name)
yield from super().modify_tensors(data_torch, new_name, bid)
@ModelBase.register("RuGPT3XLForCausalLM")
class RuGPT3XLModel(TextModel):
model_arch = gguf.MODEL_ARCH.GPT2
_qkv_parts: list[dict[str, Tensor]] | None = None
def modify_tensors(self, data_torch: Tensor, name: str, bid: int | None) -> Iterable[tuple[str, Tensor]]:
# Fuse separate Q, K, V projections into a single QKV tensor
if ".self_attn.q_proj." in name or ".self_attn.k_proj." in name or ".self_attn.v_proj." in name:
suffix = "weight" if name.endswith(".weight") else "bias"
part = "q" if ".q_proj." in name else ("k" if ".k_proj." in name else "v")
key = f"{part}.{suffix}"
assert bid is not None
if self._qkv_parts is None:
self._qkv_parts = [{} for _ in range(self.block_count)]
self._qkv_parts[bid][key] = data_torch
q_key, k_key, v_key = f"q.{suffix}", f"k.{suffix}", f"v.{suffix}"
if all(k in self._qkv_parts[bid] for k in [q_key, k_key, v_key]):
q = self._qkv_parts[bid].pop(q_key)
k = self._qkv_parts[bid].pop(k_key)
v = self._qkv_parts[bid].pop(v_key)
data_torch = torch.cat([q, k, v], dim=0)
name = self.format_tensor_name(gguf.MODEL_TENSOR.ATTN_QKV, bid, f".{suffix}")
logger.debug(f"Fused Q/K/V {suffix} for layer {bid} -> {name}")
else:
return
yield from super().modify_tensors(data_torch, name, bid)
def prepare_tensors(self):
super().prepare_tensors()
if self._qkv_parts is not None:
# flatten `list[dict[str, Tensor]]` into `list[str]`
parts = [f"({i}){k}" for i, d in enumerate(self._qkv_parts) for k in d.keys()]
if len(parts) > 0:
raise ValueError(f"Unprocessed Q/K/V parts: {parts}")