MiniCPM implementation (#685)

* Added support for the MiniCPM architecture

* Added support for the MiniCPM architecture

* Updated utils.py and LORA.md

* Updated utils.py and LORA.md

* Update implementation details for MiniCPM architecture

* Cleaning up

* fixed the missing lm.head layer problem

* Refactor Model class to dynamically handle tied and untied word embeddings

* Quick update

* added a dynamic rope scaling base calucaltion

* Added support for the MiniCPM architecture

* Added support for the MiniCPM architecture

* Updated utils.py and LORA.md

* Updated utils.py and LORA.md

* Update implementation details for MiniCPM architecture

* Cleaning up

* fixed the missing lm.head layer problem

* Refactor Model class to dynamically handle tied and untied word embeddings

* added a dynamic rope scaling base calucaltion

* quick fix and clean up

* clean up again

* removed the MiniCPMNorm class as its not used

* forgot something, sorry

* format

* version bump

---------

Co-authored-by: Awni Hannun <awni@apple.com>
This commit is contained in:
Gökdeniz Gülmez
2024-04-26 00:29:28 +02:00
committed by GitHub
parent 685012c2ad
commit 2c1c9e9024
4 changed files with 251 additions and 22 deletions

View File

@@ -0,0 +1,212 @@
from dataclasses import dataclass
from typing import Dict, Optional, Tuple, Union
import mlx.core as mx
import mlx.nn as nn
import numpy as np
from .base import BaseModelArgs
@dataclass
class ModelArgs(BaseModelArgs):
model_type: str
hidden_size: int
dim_model_base: int
num_hidden_layers: int
intermediate_size: int
num_attention_heads: int
rms_norm_eps: float
vocab_size: int
num_key_value_heads: int
max_position_embeddings: int
scale_depth: float
scale_emb: float
rope_theta: float = 1000000.0
rope_traditional: bool = False
rope_scaling: Optional[Dict[str, Union[str, float]]] = None
tie_word_embeddings: bool = False
class MLP(nn.Module):
def __init__(self, args):
super().__init__()
self.gate_proj = nn.Linear(args.hidden_size, args.intermediate_size, bias=False)
self.up_proj = nn.Linear(args.hidden_size, args.intermediate_size, bias=False)
self.down_proj = nn.Linear(args.intermediate_size, args.hidden_size, bias=False)
def __call__(self, x):
return self.down_proj(nn.silu(self.gate_proj(x)) * self.up_proj(x))
class Attention(nn.Module):
def __init__(self, args: ModelArgs):
super().__init__()
self.args = args
self.hidden_size = args.hidden_size
self.num_heads = n_heads = args.num_attention_heads
self.rope_theta = args.rope_theta
self.max_position_embeddings = args.max_position_embeddings
self.head_dim = head_dim = args.hidden_size // n_heads
self.scale = head_dim**-0.5
self.num_key_value_heads = args.num_key_value_heads
self.num_key_value_groups = self.num_heads // self.num_key_value_heads
self.q_proj = nn.Linear(
self.hidden_size, self.num_heads * self.head_dim, bias=False
)
self.k_proj = nn.Linear(
self.hidden_size, self.num_key_value_heads * self.head_dim, bias=False
)
self.v_proj = nn.Linear(
self.hidden_size, self.num_key_value_heads * self.head_dim, bias=False
)
self.o_proj = nn.Linear(
self.num_heads * self.head_dim, self.hidden_size, bias=False
)
rope_scale = (
1 / args.rope_scaling["factor"]
if args.rope_scaling is not None and args.rope_scaling["type"] == "linear"
else 1
)
self.rope = nn.RoPE(
dims=self.head_dim,
traditional=args.rope_traditional,
base=self.rope_theta,
scale=rope_scale,
)
def __call__(
self,
x: mx.array,
mask: Optional[mx.array] = None,
cache: Optional[Tuple[mx.array, mx.array]] = None,
):
B, L, _ = x.shape
queries, keys, values = self.q_proj(x), self.k_proj(x), self.v_proj(x)
queries = queries.reshape(B, L, self.num_heads, -1).transpose(0, 2, 1, 3)
keys = keys.reshape(B, L, self.num_key_value_heads, -1).transpose(0, 2, 1, 3)
values = values.reshape(B, L, self.num_key_value_heads, -1).transpose(
0, 2, 1, 3
)
if cache is not None:
key_cache, value_cache = cache
queries = self.rope(queries, offset=key_cache.shape[2])
keys = self.rope(keys, offset=key_cache.shape[2])
keys = mx.concatenate([key_cache, keys], axis=2)
values = mx.concatenate([value_cache, values], axis=2)
else:
queries = self.rope(queries)
keys = self.rope(keys)
attn_output = mx.fast.scaled_dot_product_attention(
queries, keys, values, scale=self.scale, mask=mask
)
attn_output = attn_output.transpose(0, 2, 1, 3).reshape(B, L, -1)
return self.o_proj(attn_output), (keys, values)
class DecoderLayer(nn.Module):
def __init__(self, args: ModelArgs):
super().__init__()
self.args = args
self.hidden_size = args.hidden_size
self.num_hidden_layers = args.num_hidden_layers
self.self_attn = Attention(args)
self.mlp = MLP(args)
self.input_layernorm = nn.RMSNorm(args.hidden_size, eps=args.rms_norm_eps)
self.post_attention_layernorm = nn.RMSNorm(
args.hidden_size, eps=args.rms_norm_eps
)
self.scale_depth = args.scale_depth
self.num_hidden_layers = args.num_hidden_layers
def __call__(
self,
x: mx.array,
mask: Optional[mx.array] = None,
cache: Optional[Tuple[mx.array, mx.array]] = None,
) -> mx.array:
r, cache = self.self_attn(self.input_layernorm(x), mask, cache)
h = x + r * (self.scale_depth / np.sqrt(self.num_hidden_layers))
r = self.mlp(self.post_attention_layernorm(h))
out = h + r * (self.scale_depth / np.sqrt(self.num_hidden_layers))
return out, cache
class MiniCPMModel(nn.Module):
def __init__(self, args: ModelArgs):
super().__init__()
self.args = args
self.vocab_size = args.vocab_size
assert self.vocab_size > 0
self.embed_tokens = nn.Embedding(args.vocab_size, args.hidden_size)
self.layers = [DecoderLayer(args) for _ in range(args.num_hidden_layers)]
self.norm = nn.RMSNorm(args.hidden_size, eps=args.rms_norm_eps)
def __call__(
self,
inputs: mx.array,
cache=None,
):
h = self.embed_tokens(inputs) * self.args.scale_emb
mask = None
if h.shape[1] > 1:
mask = nn.MultiHeadAttention.create_additive_causal_mask(h.shape[1])
mask = mask.astype(h.dtype)
if cache is None:
cache = [None] * len(self.layers)
for e, layer in enumerate(self.layers):
h, cache[e] = layer(h, mask, cache[e])
return self.norm(h), cache
class Model(nn.Module):
def __init__(self, args: ModelArgs):
super().__init__()
self.args = args
self.model_type = args.model_type
self.model = MiniCPMModel(args)
if not self.args.tie_word_embeddings:
self.lm_head = nn.Linear(args.hidden_size, args.vocab_size, bias=False)
def __call__(
self,
inputs: mx.array,
cache=None,
):
out, cache = self.model(inputs, cache)
if not self.args.tie_word_embeddings:
out = self.lm_head(out / (self.args.hidden_size / self.args.dim_model_base))
else:
out = out @ self.model.embed_tokens.weight.T
return out, cache
def sanitize(self, weights):
if "lm_head.weight" not in weights:
weights["lm_head.weight"] = weights["model.embed_tokens.weight"]
return weights
@property
def layers(self):
return self.model.layers