# 🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨 # This file was automatically generated from src/transformers/models/gemma3/modular_gemma3.py. # Do NOT edit this file manually as any edits will be overwritten by the generation of # the file from the modular. If any change should be done, please apply the change to the # modular_gemma3.py file directly. One of our CI enforces this. # 🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨 # Copyright 2025 Google Inc. HuggingFace Inc. 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. from collections.abc import Callable from dataclasses import dataclass from typing import Optional import torch import torch.nn as nn import torch.nn.functional as F from transformers import initialization as init from transformers.activations import ACT2FN from transformers.cache_utils import Cache, DynamicCache from transformers.configuration_utils import PreTrainedConfig from transformers.generation import GenerationMixin from transformers.integrations import use_kernel_func_from_hub, use_kernelized_func from transformers.masking_utils import create_causal_mask, create_masks_for_generate, create_sliding_window_causal_mask from transformers.modeling_layers import GenericForSequenceClassification, GradientCheckpointingLayer from transformers.modeling_outputs import ( BaseModelOutputWithPast, BaseModelOutputWithPooling, CausalLMOutputWithPast, SequenceClassifierOutputWithPast, ) from transformers.modeling_rope_utils import ROPE_INIT_FUNCTIONS, dynamic_rope_update from transformers.modeling_utils import ALL_ATTENTION_FUNCTIONS, PreTrainedModel from transformers.processing_utils import Unpack from transformers.utils import ModelOutput, TransformersKwargs, auto_docstring, can_return_tuple, torch_compilable_check from transformers.utils.generic import maybe_autocast, merge_with_config_defaults from transformers.utils.output_capturing import capture_outputs from transformers import AutoModel from configuration_gemma3 import Gemma3Config, Gemma3TextConfig from p28_modules import LTIInjection, StabilityMonitor, ReadOnlyCache @auto_docstring( custom_intro=""" Base class for Gemma3 outputs, with hidden states and attentions. """ ) @dataclass class Gemma3ModelOutputWithPast(BaseModelOutputWithPast): r""" image_hidden_states (`torch.FloatTensor`, *optional*): A `torch.FloatTensor` of size `(batch_size, num_images, sequence_length, hidden_size)`. image_hidden_states of the model produced by the vision encoder and after projecting the last hidden state. """ image_hidden_states: torch.FloatTensor | None = None @auto_docstring( custom_intro=""" Base class for Gemma3 causal language model (or autoregressive) outputs. """ ) @dataclass class Gemma3CausalLMOutputWithPast(ModelOutput): r""" loss (`torch.FloatTensor` of shape `(1,)`, *optional*, returned when `labels` is provided): Language modeling loss (for next-token prediction). logits (`torch.FloatTensor` of shape `(batch_size, sequence_length, config.text_config.vocab_size)`): Prediction scores of the language modeling head (scores for each vocabulary token before SoftMax). past_key_values (`Cache`, *optional*, returned when `use_cache=True` is passed or when `config.use_cache=True`): It is a [`~cache_utils.Cache`] instance. For more details, see our [kv cache guide](https://huggingface.co/docs/transformers/en/kv_cache). Contains pre-computed hidden-states (key and values in the self-attention blocks) that can be used (see `past_key_values` input) to speed up sequential decoding. image_hidden_states (`torch.FloatTensor`, *optional*): A `torch.FloatTensor` of size `(batch_size, num_images, sequence_length, hidden_size)`. image_hidden_states of the model produced by the vision encoder after projecting last hidden state. """ loss: torch.FloatTensor | None = None logits: torch.FloatTensor | None = None past_key_values: Cache | None = None hidden_states: tuple[torch.FloatTensor] | None = None attentions: tuple[torch.FloatTensor] | None = None image_hidden_states: torch.FloatTensor | None = None class Gemma3TextScaledWordEmbedding(nn.Embedding): """ This module overrides nn.Embeddings' forward by multiplying with embeddings scale. """ def __init__(self, num_embeddings: int, embedding_dim: int, padding_idx: int, embed_scale: float = 1.0): super().__init__(num_embeddings, embedding_dim, padding_idx) self.scalar_embed_scale = embed_scale self.register_buffer("embed_scale", torch.tensor(embed_scale), persistent=False) def forward(self, input_ids: torch.Tensor): return super().forward(input_ids) * self.embed_scale.to(self.weight.dtype) class Gemma3MLP(nn.Module): def __init__(self, config: Gemma3TextConfig): super().__init__() self.config = config self.hidden_size = config.hidden_size self.intermediate_size = config.intermediate_size self.gate_proj = nn.Linear(self.hidden_size, self.intermediate_size, bias=False) self.up_proj = nn.Linear(self.hidden_size, self.intermediate_size, bias=False) self.down_proj = nn.Linear(self.intermediate_size, self.hidden_size, bias=False) self.act_fn = ACT2FN[config.hidden_activation] def forward(self, x): down_proj = self.down_proj(self.act_fn(self.gate_proj(x)) * self.up_proj(x)) return down_proj class Gemma3RMSNorm(nn.Module): def __init__(self, dim: int, eps: float = 1e-6): super().__init__() self.eps = eps self.weight = nn.Parameter(torch.zeros(dim)) def _norm(self, x): return x * torch.rsqrt(x.pow(2).mean(-1, keepdim=True) + self.eps) def forward(self, x): output = self._norm(x.float()) # Llama does x.to(float16) * w whilst Gemma3 is (x * w).to(float16) # See https://github.com/huggingface/transformers/pull/29402 output = output * (1.0 + self.weight.float()) return output.type_as(x) def extra_repr(self): return f"{tuple(self.weight.shape)}, eps={self.eps}" class Gemma3RotaryEmbedding(nn.Module): inv_freq: torch.Tensor # fix linting for `register_buffer` def __init__(self, config: Gemma3TextConfig): super().__init__() self.max_seq_len_cached = config.max_position_embeddings self.original_max_seq_len = config.max_position_embeddings self.config = config self.layer_types = list(set(config.layer_types)) self.rope_type = {} for layer_type in self.layer_types: rope_params = self.config.rope_parameters[layer_type] if rope_params is None: continue self.rope_type[layer_type] = rope_params["rope_type"] rope_init_fn: Callable = self.compute_default_rope_parameters if self.rope_type[layer_type] != "default": rope_init_fn = ROPE_INIT_FUNCTIONS[self.rope_type[layer_type]] curr_inv_freq, curr_attention_scaling = rope_init_fn(self.config, layer_type=layer_type) self.register_buffer(f"{layer_type}_inv_freq", curr_inv_freq, persistent=False) self.register_buffer(f"{layer_type}_original_inv_freq", curr_inv_freq.clone(), persistent=False) setattr(self, f"{layer_type}_attention_scaling", curr_attention_scaling) @staticmethod def compute_default_rope_parameters( config: Gemma3TextConfig | None = None, device: Optional["torch.device"] = None, seq_len: int | None = None, layer_type: str | None = None, ) -> tuple["torch.Tensor", float]: """ Computes the inverse frequencies according to the original RoPE implementation Args: config ([`~transformers.PreTrainedConfig`]): The model configuration. device (`torch.device`): The device to use for initialization of the inverse frequencies. seq_len (`int`, *optional*): The current sequence length. Unused for this type of RoPE. layer_type (`str`, *optional*): The current layer type if the model has different RoPE parameters per type. Should not be used unless `config.layer_types is not None` Returns: Tuple of (`torch.Tensor`, `float`), containing the inverse frequencies for the RoPE embeddings and the post-processing scaling factor applied to the computed cos/sin (unused in this type of RoPE). """ # For backward compatibility standardize the `rope_parameters_dict` if it uses old format base = config.rope_parameters[layer_type]["rope_theta"] dim = getattr(config, "head_dim", None) or config.hidden_size // config.num_attention_heads attention_factor = 1.0 # Unused in this type of RoPE # Compute the inverse frequencies inv_freq = 1.0 / ( base ** (torch.arange(0, dim, 2, dtype=torch.int64).to(device=device, dtype=torch.float) / dim) ) return inv_freq, attention_factor @torch.no_grad() @dynamic_rope_update # power user: used with advanced RoPE types (e.g. dynamic rope) def forward(self, x, position_ids, layer_type=None): inv_freq = getattr(self, f"{layer_type}_inv_freq") attention_scaling = getattr(self, f"{layer_type}_attention_scaling") inv_freq_expanded = inv_freq[None, :, None].float().expand(position_ids.shape[0], -1, 1).to(x.device) position_ids_expanded = position_ids[:, None, :].float() device_type = x.device.type if isinstance(x.device.type, str) and x.device.type != "mps" else "cpu" with maybe_autocast(device_type=device_type, enabled=False): # Force float32 freqs = (inv_freq_expanded.float() @ position_ids_expanded.float()).transpose(1, 2) emb = torch.cat((freqs, freqs), dim=-1) cos = emb.cos() * attention_scaling sin = emb.sin() * attention_scaling return cos.to(dtype=x.dtype), sin.to(dtype=x.dtype) def rotate_half(x): """Rotates half the hidden dims of the input.""" x1 = x[..., : x.shape[-1] // 2] x2 = x[..., x.shape[-1] // 2 :] return torch.cat((-x2, x1), dim=-1) @use_kernel_func_from_hub("rotary_pos_emb") def apply_rotary_pos_emb(q, k, cos, sin, unsqueeze_dim=1): """Applies Rotary Position Embedding to the query and key tensors. Args: q (`torch.Tensor`): The query tensor. k (`torch.Tensor`): The key tensor. cos (`torch.Tensor`): The cosine part of the rotary embedding. sin (`torch.Tensor`): The sine part of the rotary embedding. unsqueeze_dim (`int`, *optional*, defaults to 1): The 'unsqueeze_dim' argument specifies the dimension along which to unsqueeze cos[position_ids] and sin[position_ids] so that they can be properly broadcasted to the dimensions of q and k. For example, note that cos[position_ids] and sin[position_ids] have the shape [batch_size, seq_len, head_dim]. Then, if q and k have the shape [batch_size, heads, seq_len, head_dim], then setting unsqueeze_dim=1 makes cos[position_ids] and sin[position_ids] broadcastable to the shapes of q and k. Similarly, if q and k have the shape [batch_size, seq_len, heads, head_dim], then set unsqueeze_dim=2. Returns: `tuple(torch.Tensor)` comprising of the query and key tensors rotated using the Rotary Position Embedding. """ cos = cos.unsqueeze(unsqueeze_dim) sin = sin.unsqueeze(unsqueeze_dim) q_embed = (q * cos) + (rotate_half(q) * sin) k_embed = (k * cos) + (rotate_half(k) * sin) return q_embed, k_embed def repeat_kv(hidden_states: torch.Tensor, n_rep: int) -> torch.Tensor: """ This is the equivalent of torch.repeat_interleave(x, dim=1, repeats=n_rep). The hidden states go from (batch, num_key_value_heads, seqlen, head_dim) to (batch, num_attention_heads, seqlen, head_dim) """ batch, num_key_value_heads, slen, head_dim = hidden_states.shape if n_rep == 1: return hidden_states hidden_states = hidden_states[:, :, None, :, :].expand(batch, num_key_value_heads, n_rep, slen, head_dim) return hidden_states.reshape(batch, num_key_value_heads * n_rep, slen, head_dim) def eager_attention_forward( module: nn.Module, query: torch.Tensor, key: torch.Tensor, value: torch.Tensor, attention_mask: torch.Tensor | None, dropout: float | int = 0.0, scaling: float | None = None, softcap: float | None = None, **kwargs, ) -> tuple[torch.Tensor, torch.Tensor]: if scaling is None: scaling = module.head_dim**-0.5 key_states = repeat_kv(key, module.num_key_value_groups) value_states = repeat_kv(value, module.num_key_value_groups) attn_weights = torch.matmul(query, key_states.transpose(2, 3)) * scaling if softcap is not None: attn_weights = attn_weights / softcap attn_weights = torch.tanh(attn_weights) attn_weights = attn_weights * softcap if attention_mask is not None: attn_weights = attn_weights + attention_mask # upcast attention to fp32 attn_weights = nn.functional.softmax(attn_weights, dim=-1, dtype=torch.float32).to(query.dtype) attn_weights = nn.functional.dropout(attn_weights, p=dropout, training=module.training) attn_output = torch.matmul(attn_weights, value_states) attn_output = attn_output.transpose(1, 2).contiguous() return attn_output, attn_weights @use_kernelized_func(apply_rotary_pos_emb) class Gemma3Attention(nn.Module): """Multi-headed attention from 'Attention Is All You Need' paper""" def __init__(self, config: Gemma3TextConfig, layer_idx: int): super().__init__() self.layer_type = config.layer_types[layer_idx] if hasattr(config, "layer_types") else None self.config = config self.layer_idx = layer_idx self.head_dim = getattr(config, "head_dim", config.hidden_size // config.num_attention_heads) self.num_key_value_groups = config.num_attention_heads // config.num_key_value_heads self.scaling = config.query_pre_attn_scalar**-0.5 self.attention_dropout = self.config.attention_dropout self.is_causal = not self.config.use_bidirectional_attention self.q_proj = nn.Linear( config.hidden_size, config.num_attention_heads * self.head_dim, bias=config.attention_bias ) self.k_proj = nn.Linear( config.hidden_size, config.num_key_value_heads * self.head_dim, bias=config.attention_bias ) self.v_proj = nn.Linear( config.hidden_size, config.num_key_value_heads * self.head_dim, bias=config.attention_bias ) self.o_proj = nn.Linear( config.num_attention_heads * self.head_dim, config.hidden_size, bias=config.attention_bias ) self.attn_logit_softcapping = self.config.attn_logit_softcapping self.sliding_window = config.sliding_window if self.layer_type == "sliding_attention" else None self.is_sliding = self.layer_type == "sliding_attention" self.q_norm = Gemma3RMSNorm(dim=config.head_dim, eps=config.rms_norm_eps) self.k_norm = Gemma3RMSNorm(dim=config.head_dim, eps=config.rms_norm_eps) def forward( self, hidden_states: torch.Tensor, position_embeddings: torch.Tensor = None, attention_mask: torch.Tensor | None = None, past_key_values: Cache | None = None, **kwargs: Unpack[TransformersKwargs], ) -> tuple[torch.Tensor, torch.Tensor | None, tuple[torch.Tensor] | None]: input_shape = hidden_states.shape[:-1] hidden_shape = (*input_shape, -1, self.head_dim) query_states = self.q_proj(hidden_states).view(hidden_shape).transpose(1, 2) key_states = self.k_proj(hidden_states).view(hidden_shape).transpose(1, 2) value_states = self.v_proj(hidden_states).view(hidden_shape).transpose(1, 2) query_states = self.q_norm(query_states) key_states = self.k_norm(key_states) cos, sin = position_embeddings query_states, key_states = apply_rotary_pos_emb(query_states, key_states, cos, sin) if past_key_values is not None: key_states, value_states = past_key_values.update(key_states, value_states, self.layer_idx) attention_interface: Callable = ALL_ATTENTION_FUNCTIONS.get_interface( self.config._attn_implementation, eager_attention_forward ) attn_output, attn_weights = attention_interface( self, query_states, key_states, value_states, attention_mask, dropout=self.attention_dropout if self.training else 0.0, scaling=self.scaling, sliding_window=self.sliding_window, **kwargs, ) attn_output = attn_output.reshape(*input_shape, -1).contiguous() attn_output = self.o_proj(attn_output) return attn_output, attn_weights class Gemma3DecoderLayer(GradientCheckpointingLayer): def __init__(self, config: Gemma3TextConfig, layer_idx: int): super().__init__() self.config = config self.hidden_size = config.hidden_size self.layer_idx = layer_idx self.self_attn = Gemma3Attention(config=config, layer_idx=layer_idx) self.mlp = Gemma3MLP(config) self.input_layernorm = Gemma3RMSNorm(self.hidden_size, eps=config.rms_norm_eps) self.post_attention_layernorm = Gemma3RMSNorm(self.hidden_size, eps=config.rms_norm_eps) self.pre_feedforward_layernorm = Gemma3RMSNorm(self.hidden_size, eps=config.rms_norm_eps) self.post_feedforward_layernorm = Gemma3RMSNorm(self.hidden_size, eps=config.rms_norm_eps) def forward( self, hidden_states: torch.Tensor, position_embeddings: torch.Tensor = None, attention_mask: torch.Tensor | None = None, position_ids: torch.LongTensor | None = None, past_key_values: Cache | None = None, **kwargs: Unpack[TransformersKwargs], ) -> tuple[torch.FloatTensor, tuple[torch.FloatTensor, torch.FloatTensor] | None]: residual = hidden_states hidden_states = self.input_layernorm(hidden_states) hidden_states, _ = self.self_attn( hidden_states=hidden_states, position_embeddings=position_embeddings, attention_mask=attention_mask, position_ids=position_ids, past_key_values=past_key_values, **kwargs, ) hidden_states = self.post_attention_layernorm(hidden_states) hidden_states = residual + hidden_states residual = hidden_states hidden_states = self.pre_feedforward_layernorm(hidden_states) hidden_states = self.mlp(hidden_states) hidden_states = self.post_feedforward_layernorm(hidden_states) hidden_states = residual + hidden_states return hidden_states @auto_docstring class Gemma3PreTrainedModel(PreTrainedModel): config: Gemma3Config base_model_prefix = "model" supports_gradient_checkpointing = True _no_split_modules = [ "Gemma3DecoderLayer", "SiglipVisionEmbeddings", "SiglipEncoderLayer", "SiglipMultiheadAttentionPoolingHead", ] _skip_keys_device_placement = ["past_key_values"] _supports_flash_attn = True _supports_sdpa = True _supports_flex_attn = True _can_compile_fullgraph = True _supports_attention_backend = True _can_record_outputs = { "hidden_states": Gemma3DecoderLayer, "attentions": Gemma3Attention, } input_modalities = ("image", "text") @torch.no_grad() def _init_weights(self, module): super()._init_weights(module) if isinstance(module, Gemma3MultiModalProjector): init.zeros_(module.mm_input_projection_weight) # We initialize with 0s to be 1 centered as the RMSNorm here does (1 + weight) elif "RMSNorm" in module.__class__.__name__: init.zeros_(module.weight) elif isinstance(module, Gemma3TextScaledWordEmbedding): init.constant_(module.embed_scale, module.scalar_embed_scale) elif isinstance(module, Gemma3RotaryEmbedding): for layer_type in module.layer_types: rope_init_fn = module.compute_default_rope_parameters if module.rope_type[layer_type] != "default": rope_init_fn = ROPE_INIT_FUNCTIONS[module.rope_type[layer_type]] curr_inv_freq, _ = rope_init_fn(module.config, layer_type=layer_type) init.copy_(getattr(module, f"{layer_type}_inv_freq"), curr_inv_freq) init.copy_(getattr(module, f"{layer_type}_original_inv_freq"), curr_inv_freq) def _bidirectional_window_overlay(sliding_window: int) -> Callable[[int, int, int, int], bool]: """ Enables a bidirectional mask within the sliding window. """ def inner_mask(batch_idx: int, head_idx: int, q_idx: int, kv_idx: int) -> bool: """A token can attend to any other token if their absolute distance is within the (exclusive) sliding window size (distance < sliding_window).""" return abs(q_idx - kv_idx) < sliding_window return inner_mask @auto_docstring class Gemma3TextModel(Gemma3PreTrainedModel): config: Gemma3TextConfig input_modalities = ("text",) def __init__(self, config: Gemma3TextConfig): super().__init__(config) self.padding_idx = config.pad_token_id self.vocab_size = config.vocab_size # Gemma3 downcasts the below to bfloat16, causing sqrt(3072)=55.4256 to become 55.5. See https://github.com/huggingface/transformers/pull/29402 self.embed_tokens = Gemma3TextScaledWordEmbedding( config.vocab_size, config.hidden_size, self.padding_idx, embed_scale=self.config.hidden_size**0.5 ) self.layers = nn.ModuleList( [Gemma3DecoderLayer(config, layer_idx) for layer_idx in range(config.num_hidden_layers)] ) self.norm = Gemma3RMSNorm(config.hidden_size, eps=config.rms_norm_eps) self.rotary_emb = Gemma3RotaryEmbedding(config) self.gradient_checkpointing = False # p2.8 Core Components (Pure Zero-Shot) self.p28_injection = LTIInjection(config.hidden_size) self.p28_refine_weight = 0.05 # Winning RefineWeight from Sweep # p2.8 Runtime Metrics (Heuristic-based) self._phi_log = 1.0 self._lambda_log = 0.0 # Initialize weights and apply final processing self.post_init() # Ensure custom modules are in the right dtype if hasattr(config, "torch_dtype") and config.torch_dtype is not None: self.p28_injection.to(config.torch_dtype) @merge_with_config_defaults @capture_outputs @auto_docstring def forward( self, input_ids: torch.LongTensor | None = None, attention_mask: torch.Tensor | None = None, position_ids: torch.LongTensor | None = None, past_key_values: Cache | None = None, inputs_embeds: torch.FloatTensor | None = None, use_cache: bool | None = None, **kwargs: Unpack[TransformersKwargs], ) -> BaseModelOutputWithPast: if (input_ids is None) ^ (inputs_embeds is not None): raise ValueError("You must specify exactly one of input_ids or inputs_embeds") if inputs_embeds is None: inputs_embeds = self.embed_tokens(input_ids) if use_cache and past_key_values is None: past_key_values = DynamicCache(config=self.config) if position_ids is None: past_seen_tokens = past_key_values.get_seq_length() if past_key_values is not None else 0 position_ids = torch.arange(inputs_embeds.shape[1], device=inputs_embeds.device) + past_seen_tokens position_ids = position_ids.unsqueeze(0) # It may already have been prepared by e.g. `generate` if not isinstance(causal_mask_mapping := attention_mask, dict): # Prepare mask arguments mask_kwargs = { "config": self.config, "inputs_embeds": inputs_embeds, "attention_mask": attention_mask, "past_key_values": past_key_values, "position_ids": position_ids, } sliding_mask_kwargs = mask_kwargs.copy() if self.config.use_bidirectional_attention: mask_kwargs["or_mask_function"] = lambda *args: torch.tensor(True, dtype=torch.bool) sliding_mask_kwargs["or_mask_function"] = _bidirectional_window_overlay(self.config.sliding_window) # Create the masks causal_mask_mapping = { "full_attention": create_causal_mask(**mask_kwargs), "sliding_attention": create_sliding_window_causal_mask(**sliding_mask_kwargs), } # embed positions hidden_states = inputs_embeds position_embeddings = {} for layer_type in set(self.config.layer_types): position_embeddings[layer_type] = self.rotary_emb(hidden_states, position_ids, layer_type) # --- START p2.8 ARCHITECTURE --- # 1. Prelude (Layers 0-5) for i in range(6): hidden_states = self.layers[i]( hidden_states, attention_mask=causal_mask_mapping[self.config.layer_types[i]], position_embeddings=position_embeddings[self.config.layer_types[i]], position_ids=position_ids, past_key_values=past_key_values, **kwargs, ) # 2. Recurrent Block (Layers 6-11) e_static = hidden_states.clone() # Anchor snapshot h = hidden_states B, T, D = h.shape phi_history = [] phi = 1.0 loop_outputs = [] n_loops_base = 2 t = 0 while t < 4: # Hard limit for safety h_prev = h.clone() # Mode Selection: Linear State Progression (LSP) if t == 0: e_mode = e_static else: phi_val = max(0.0, min(1.0, phi)) alpha = max(0.0, min(0.5, (1.0 - phi_val) * 2.0)) e_mode = (1.0 - alpha) * e_static + alpha * h_prev.clone() # p5.1: Context-Preserving KV-Sync if t == 0: current_past = past_key_values elif past_key_values is not None: current_past = ReadOnlyCache(past_key_values) else: current_past = None trans_out = h for i_loop in range(6, 12): l_type = self.config.layer_types[i_loop] layer_out = self.layers[i_loop]( trans_out, attention_mask=causal_mask_mapping[l_type], position_embeddings=position_embeddings[l_type], position_ids=position_ids, past_key_values=current_past, **kwargs, ) trans_out = layer_out[0] if isinstance(layer_out, (tuple, list)) else layer_out # Injection h = self.p28_injection(h_prev, e_mode, trans_out) phi_tensor = StabilityMonitor.calculate_phi(h, h_prev) phi = phi_tensor.item() phi_history.append(phi_tensor) # p4.0: Lambda-Gated State Reset (LGSR) lambda_val = StabilityMonitor.detect_lambda(h, e_static).item() # p5.2: Orthogonal Thinking (OT) if t > 0: dot_he = (h * e_static).sum(dim=-1, keepdim=True) dot_ee = (e_static * e_static).sum(dim=-1, keepdim=True) proj = (dot_he / (dot_ee + 1e-6)) * e_static ortho = h - proj # Dampen Identity drift, keep Orthogonal logic h = 0.95 * proj + 1.05 * ortho if lambda_val > 0.55: h = 0.8 * h + 0.2 * e_static # Pull back to manifold loop_outputs.append(h.clone()) t += 1 # Dynamic Expansion Logic if t == n_loops_base: avg_phi = torch.stack(phi_history).mean().item() if avg_phi < 0.85: # threshold from DEFAULT_PHI_LOOP_THRESHOLD continue else: break elif t >= n_loops_base + 1: break # Final Normalized Blend (Signal Preservation) phi0 = phi_history[0].item() # p4.1: Quadratic Beta Interpolation (QBI) Approximation b_min = 0.05 b_max = 0.18 beta_final = b_min + (b_max - b_min) * (phi0 ** 2) if len(loop_outputs) > 1: h_base = loop_outputs[0] h_t1 = loop_outputs[1] if len(loop_outputs) > 2: h_t2 = loop_outputs[2] h_refined = 0.7 * h_t1 + 0.3 * h_t2 beta_final = beta_final * 0.8 else: h_refined = h_t1 hidden_states = (1.0 - beta_final) * h_base + beta_final * h_refined else: hidden_states = loop_outputs[0] # Store diagnostics self._phi_log = torch.stack(phi_history).mean().item() self._lambda_log = StabilityMonitor.detect_lambda(hidden_states, e_static).item() # 3. Coda (Layers 12-17) for i in range(12, 18): hidden_states = self.layers[i]( hidden_states, attention_mask=causal_mask_mapping[self.config.layer_types[i]], position_embeddings=position_embeddings[self.config.layer_types[i]], position_ids=position_ids, past_key_values=past_key_values, **kwargs, ) # --- END p2.8 ARCHITECTURE --- hidden_states = self.norm(hidden_states) return BaseModelOutputWithPast( last_hidden_state=hidden_states, past_key_values=past_key_values, ) @auto_docstring class Gemma3ForCausalLM(Gemma3PreTrainedModel, GenerationMixin): _tied_weights_keys = {"lm_head.weight": "model.embed_tokens.weight"} _tp_plan = {"lm_head": "colwise_gather_output"} _pp_plan = {"lm_head": (["hidden_states"], ["logits"])} config: Gemma3TextConfig def __init__(self, config: Gemma3TextConfig): super().__init__(config) self.model = Gemma3TextModel(config) self.vocab_size = config.vocab_size self.lm_head = nn.Linear(config.hidden_size, config.vocab_size, bias=False) # Initialize weights and apply final processing self.post_init() @can_return_tuple @auto_docstring def forward( self, input_ids: torch.LongTensor | None = None, attention_mask: torch.Tensor | None = None, position_ids: torch.LongTensor | None = None, past_key_values: Cache | None = None, inputs_embeds: torch.FloatTensor | None = None, labels: torch.LongTensor | None = None, use_cache: bool | None = None, logits_to_keep: int | torch.Tensor = 0, **kwargs: Unpack[TransformersKwargs], ) -> CausalLMOutputWithPast: r""" Example: ```python >>> from transformers import AutoTokenizer, Gemma3ForCausalLM >>> model = Gemma3ForCausalLM.from_pretrained("google/gemma-2-9b") >>> tokenizer = AutoTokenizer.from_pretrained("google/gemma-2-9b") >>> prompt = "What is your favorite condiment?" >>> inputs = tokenizer(prompt, return_tensors="pt") >>> # Generate >>> generate_ids = model.generate(inputs.input_ids, max_length=30) >>> tokenizer.batch_decode(generate_ids, skip_special_tokens=True, clean_up_tokenization_spaces=False)[0] "What is your favorite condiment?" ```""" # decoder outputs consists of (dec_features, layer_state, dec_hidden, dec_attn) outputs: BaseModelOutputWithPast = self.model( input_ids=input_ids, attention_mask=attention_mask, position_ids=position_ids, past_key_values=past_key_values, inputs_embeds=inputs_embeds, use_cache=use_cache, **kwargs, ) hidden_states = outputs.last_hidden_state # Only compute necessary logits, and do not upcast them to float if we are not computing the loss slice_indices = slice(-logits_to_keep, None) if isinstance(logits_to_keep, int) else logits_to_keep logits = self.lm_head(hidden_states[:, slice_indices, :]) if self.config.final_logit_softcapping is not None: logits = logits / self.config.final_logit_softcapping logits = torch.tanh(logits) logits = logits * self.config.final_logit_softcapping loss = None if labels is not None: loss = self.loss_function(logits, labels, self.vocab_size, **kwargs) return CausalLMOutputWithPast( loss=loss, logits=logits, past_key_values=outputs.past_key_values, hidden_states=outputs.hidden_states, attentions=outputs.attentions, ) class Gemma3MultiModalProjector(nn.Module): def __init__(self, config: Gemma3Config): super().__init__() self.mm_input_projection_weight = nn.Parameter( torch.zeros(config.vision_config.hidden_size, config.text_config.hidden_size) ) self.mm_soft_emb_norm = Gemma3RMSNorm( config.vision_config.hidden_size, eps=config.vision_config.layer_norm_eps ) self.patches_per_image = int(config.vision_config.image_size // config.vision_config.patch_size) self.tokens_per_side = int(config.mm_tokens_per_image**0.5) self.kernel_size = self.patches_per_image // self.tokens_per_side self.avg_pool = nn.AvgPool2d(kernel_size=self.kernel_size, stride=self.kernel_size) def forward(self, vision_outputs: torch.Tensor): batch_size, _, hidden_size = vision_outputs.shape reshaped_vision_outputs = vision_outputs.transpose(1, 2) reshaped_vision_outputs = reshaped_vision_outputs.reshape( batch_size, hidden_size, self.patches_per_image, self.patches_per_image ) reshaped_vision_outputs = reshaped_vision_outputs.contiguous() pooled_vision_outputs = self.avg_pool(reshaped_vision_outputs) pooled_vision_outputs = pooled_vision_outputs.flatten(2) pooled_vision_outputs = pooled_vision_outputs.transpose(1, 2) normed_vision_outputs = self.mm_soft_emb_norm(pooled_vision_outputs) projected_vision_outputs = torch.matmul(normed_vision_outputs, self.mm_input_projection_weight) return projected_vision_outputs.type_as(vision_outputs) def get_block_sequence_ids_for_mask(token_type_ids: torch.Tensor, device: torch.device | None = None) -> torch.Tensor: # First find where a new image block starts: 1 if image and previous not image # The images cannot attend to future images, but can attend to all prev images and to itself bidirectionally is_image = (token_type_ids == 1).to(device=device) is_previous_image = nn.functional.pad(is_image, (1, 0), value=0)[:, :-1] new_image_start = is_image & ~is_previous_image group_ids = torch.cumsum(new_image_start.int(), dim=1) - 1 block_sequence_ids = torch.where(is_image, group_ids, -1) return block_sequence_ids @auto_docstring( custom_intro=""" The Base Gemma3 model which consists of a vision backbone and a language model without language modeling head., """ ) class Gemma3Model(Gemma3PreTrainedModel): # we are filtering the logits/labels so we shouldn't divide the loss based on num_items_in_batch accepts_loss_kwargs = False def __init__(self, config: Gemma3Config): super().__init__(config) self.vision_tower = AutoModel.from_config(config=config.vision_config) self.multi_modal_projector = Gemma3MultiModalProjector(config) self.vocab_size = config.text_config.vocab_size language_model = AutoModel.from_config(config=config.text_config) self.language_model = language_model self.post_init() @can_return_tuple @auto_docstring(custom_intro="Projects the last hidden state from the vision model into language model space.") def get_image_features( self, pixel_values: torch.FloatTensor, **kwargs: Unpack[TransformersKwargs] ) -> tuple | BaseModelOutputWithPooling: vision_outputs = self.vision_tower(pixel_values=pixel_values, return_dict=True, **kwargs) last_hidden_state = vision_outputs.last_hidden_state vision_outputs.pooler_output = self.multi_modal_projector(last_hidden_state) return vision_outputs def get_placeholder_mask( self, input_ids: torch.LongTensor, inputs_embeds: torch.FloatTensor, image_features: torch.FloatTensor ): """ Obtains multimodal placeholder mask from `input_ids` or `inputs_embeds`, and checks that the placeholder token count is equal to the length of multimodal features. If the lengths are different, an error is raised. """ if input_ids is None: special_image_mask = inputs_embeds == self.get_input_embeddings()( torch.tensor(self.config.image_token_id, dtype=torch.long, device=inputs_embeds.device) ) special_image_mask = special_image_mask.all(-1) else: special_image_mask = input_ids == self.config.image_token_id n_image_tokens = special_image_mask.sum() n_image_features = image_features.shape[0] * image_features.shape[1] special_image_mask = special_image_mask.unsqueeze(-1).expand_as(inputs_embeds).to(inputs_embeds.device) torch_compilable_check( inputs_embeds[special_image_mask].numel() == image_features.numel(), f"Image features and image tokens do not match, tokens: {n_image_tokens}, features: {n_image_features}", ) return special_image_mask @can_return_tuple @auto_docstring def forward( self, input_ids: torch.LongTensor | None = None, pixel_values: torch.FloatTensor | None = None, attention_mask: torch.Tensor | None = None, position_ids: torch.LongTensor | None = None, past_key_values: Cache | None = None, token_type_ids: torch.LongTensor | None = None, inputs_embeds: torch.FloatTensor | None = None, labels: torch.LongTensor | None = None, use_cache: bool | None = None, **lm_kwargs: Unpack[TransformersKwargs], ) -> tuple | Gemma3ModelOutputWithPast: r""" labels (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*): Labels for computing the masked language modeling loss. Indices should either be in `[0, ..., config.text_config.vocab_size]` or -100 (see `input_ids` docstring). Tokens with indices set to `-100` are ignored (masked), the loss is only computed for the tokens with labels in `[0, ..., config.text_config.vocab_size]`. Example: ```python >>> from PIL import Image >>> import httpx >>> from io import BytesIO >>> from transformers import AutoProcessor, Gemma3ForConditionalGeneration >>> model = Gemma3ForConditionalGeneration.from_pretrained("google/gemma32-3b-mix-224") >>> processor = AutoProcessor.from_pretrained("google/gemma32-3b-mix-224") >>> prompt = "Where is the cat standing?" >>> url = "https://huggingface.co/datasets/huggingface/documentation-images/resolve/main/pipeline-cat-chonk.jpeg" >>> with httpx.stream("GET", url) as response: ... image = Image.open(BytesIO(response.read())) >>> inputs = processor(images=image, text=prompt, return_tensors="pt") >>> # Generate >>> generate_ids = model.generate(**inputs,) >>> processor.batch_decode(generate_ids, skip_special_tokens=True, clean_up_tokenization_spaces=False)[0] "Where is the cat standing?\nsnow" ```""" if (input_ids is None) ^ (inputs_embeds is not None): raise ValueError("You must specify exactly one of input_ids or inputs_embeds") # Replace image id with PAD if the image token if OOV, to avoid index-errors if input_ids is not None and self.config.image_token_id >= self.vocab_size: special_image_mask = input_ids == self.config.image_token_id llm_input_ids = input_ids.clone() llm_input_ids[special_image_mask] = 0 else: llm_input_ids = input_ids if inputs_embeds is None: inputs_embeds = self.get_input_embeddings()(llm_input_ids) # Merge text and images if pixel_values is not None: image_features = self.get_image_features(pixel_values, return_dict=True).pooler_output image_features = image_features.to(inputs_embeds.device, inputs_embeds.dtype) special_image_mask = self.get_placeholder_mask( input_ids, inputs_embeds=inputs_embeds, image_features=image_features ) inputs_embeds = inputs_embeds.masked_scatter(special_image_mask, image_features) # It may already have been prepared by e.g. `generate` if not isinstance(causal_mask_mapping := attention_mask, dict): mask_kwargs = { "config": self.config.get_text_config(), "inputs_embeds": inputs_embeds, "attention_mask": attention_mask, "past_key_values": past_key_values, "position_ids": position_ids, } if token_type_ids is not None: mask_kwargs["block_sequence_ids"] = get_block_sequence_ids_for_mask( token_type_ids, device=inputs_embeds.device ) # Create the masks sliding_mask_kwargs = mask_kwargs.copy() causal_mask_mapping = { "full_attention": create_causal_mask(**mask_kwargs), "sliding_attention": create_sliding_window_causal_mask(**sliding_mask_kwargs), } outputs = self.language_model( attention_mask=causal_mask_mapping, position_ids=position_ids, past_key_values=past_key_values, inputs_embeds=inputs_embeds, use_cache=use_cache, return_dict=True, **lm_kwargs, ) return Gemma3ModelOutputWithPast( last_hidden_state=outputs.last_hidden_state, past_key_values=outputs.past_key_values, hidden_states=outputs.hidden_states, attentions=outputs.attentions, image_hidden_states=image_features if pixel_values is not None else None, ) @auto_docstring( custom_intro=""" The Base Gemma3 model which consists of a vision backbone and a language model without language modeling head., """ ) class Gemma3ForConditionalGeneration(Gemma3PreTrainedModel, GenerationMixin): _tied_weights_keys = {"lm_head.weight": "model.language_model.embed_tokens.weight"} # we are filtering the logits/labels so we shouldn't divide the loss based on num_items_in_batch # Fix: https://github.com/huggingface/transformers/issues/40564 accepts_loss_kwargs = False def __init__(self, config: Gemma3Config): super().__init__(config) self.model = Gemma3Model(config) self.lm_head = nn.Linear(config.text_config.hidden_size, config.text_config.vocab_size, bias=False) self.post_init() @auto_docstring def get_image_features(self, pixel_values: torch.FloatTensor, **kwargs: Unpack[TransformersKwargs]): return self.model.get_image_features(pixel_values, **kwargs) @can_return_tuple @auto_docstring def forward( self, input_ids: torch.LongTensor | None = None, pixel_values: torch.FloatTensor | None = None, attention_mask: torch.Tensor | None = None, position_ids: torch.LongTensor | None = None, past_key_values: Cache | None = None, token_type_ids: torch.LongTensor | None = None, inputs_embeds: torch.FloatTensor | None = None, labels: torch.LongTensor | None = None, use_cache: bool | None = None, logits_to_keep: int | torch.Tensor = 0, **lm_kwargs: Unpack[TransformersKwargs], ) -> tuple | Gemma3CausalLMOutputWithPast: r""" labels (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*): Labels for computing the masked language modeling loss. Indices should either be in `[0, ..., config.text_config.vocab_size]` or -100 (see `input_ids` docstring). Tokens with indices set to `-100` are ignored (masked), the loss is only computed for the tokens with labels in `[0, ..., config.text_config.vocab_size]`. Example: ```python >>> from PIL import Image >>> import httpx >>> from io import BytesIO >>> from transformers import AutoProcessor, Gemma3ForConditionalGeneration >>> model = Gemma3ForConditionalGeneration.from_pretrained("google/gemma-3-4b-it") >>> processor = AutoProcessor.from_pretrained("google/gemma-3-4b-it") >>> messages = [ ... { ... "role": "system", ... "content": [ ... {"type": "text", "text": "You are a helpful assistant."} ... ] ... }, ... { ... "role": "user", "content": [ ... {"type": "image", "url": "https://huggingface.co/datasets/huggingface/documentation-images/resolve/main/pipeline-cat-chonk.jpeg"}, ... {"type": "text", "text": "Where is the cat standing?"}, ... ] ... }, ... ] >>> inputs = processor.apply_chat_template( ... messages, ... tokenize=True, ... return_dict=True, ... return_tensors="pt", ... add_generation_prompt=True ... ) >>> # Generate >>> generate_ids = model.generate(**inputs) >>> processor.batch_decode(generate_ids, skip_special_tokens=True, clean_up_tokenization_spaces=False)[0] "user\nYou are a helpful assistant.\n\n\n\n\n\nWhere is the cat standing?\nmodel\nBased on the image, the cat is standing in a snowy area, likely outdoors. It appears to" ``` """ outputs = self.model( input_ids=input_ids, pixel_values=pixel_values, token_type_ids=token_type_ids, attention_mask=attention_mask, position_ids=position_ids, past_key_values=past_key_values, inputs_embeds=inputs_embeds, use_cache=use_cache, labels=labels, return_dict=True, **lm_kwargs, ) hidden_states = outputs[0] # Only compute necessary logits, and do not upcast them to float if we are not computing the loss slice_indices = slice(-logits_to_keep, None) if isinstance(logits_to_keep, int) else logits_to_keep logits = self.lm_head(hidden_states[:, slice_indices, :]) loss = None if labels is not None: # Upcast to float if we need to compute the loss to avoid potential precision issues logits = logits.float() shift_logits = logits[..., :-1, :] shift_labels = labels[..., 1:] if attention_mask is not None: # we use the input attention mask to shift the logits and labels, because it is 2D. # we also crop attn mask in case it is longer, which happens in PrefixTuning with peft shift_attention_mask = attention_mask[:, -shift_logits.shape[1] :].to(logits.device) shift_logits = shift_logits[shift_attention_mask.to(logits.device) != 0].contiguous() shift_labels = shift_labels[shift_attention_mask.to(shift_labels.device) != 0].contiguous() else: shift_logits = shift_logits.contiguous() shift_labels = shift_labels.contiguous() # Flatten the tokens loss_fct = nn.CrossEntropyLoss() flat_logits = shift_logits.view(-1, self.config.text_config.vocab_size) flat_labels = shift_labels.view(-1).to(shift_logits.device) loss = loss_fct(flat_logits, flat_labels) return Gemma3CausalLMOutputWithPast( loss=loss, logits=logits, past_key_values=outputs.past_key_values, hidden_states=outputs.hidden_states, attentions=outputs.attentions, image_hidden_states=outputs.image_hidden_states, ) def prepare_inputs_for_generation( self, input_ids, past_key_values=None, inputs_embeds=None, position_ids=None, pixel_values=None, attention_mask=None, token_type_ids=None, use_cache=True, logits_to_keep=None, labels=None, is_first_iteration=False, **kwargs, ): # Overwritten -- custom `pixel_values` handling model_inputs = super().prepare_inputs_for_generation( input_ids, past_key_values=past_key_values, inputs_embeds=inputs_embeds, attention_mask=attention_mask, position_ids=position_ids, use_cache=use_cache, logits_to_keep=logits_to_keep, token_type_ids=token_type_ids, is_first_iteration=is_first_iteration, **kwargs, ) # Pixel values are used only in the first iteration if available # In subsequent iterations, they are already merged with text and cached # NOTE: first iteration doesn't have to be prefill, it can be the first # iteration with a question and cached system prompt (continue generate from cache). NOTE: use_cache=False needs pixel_values always if is_first_iteration or not use_cache: model_inputs["pixel_values"] = pixel_values else: # Don't pass to not apply bidirectional mask on top model_inputs["token_type_ids"] = None return model_inputs @staticmethod def create_masks_for_generate( config: PreTrainedConfig, inputs_embeds: torch.Tensor, attention_mask: torch.Tensor | None, past_key_values: Cache | None, position_ids: torch.Tensor | None, token_type_ids: torch.Tensor | None = None, is_first_iteration: bool | None = False, **kwargs, ) -> dict: mask_kwargs = { "config": config.get_text_config(), "inputs_embeds": inputs_embeds, "attention_mask": attention_mask, "past_key_values": past_key_values, "position_ids": position_ids, } if token_type_ids is not None: mask_kwargs["block_sequence_ids"] = get_block_sequence_ids_for_mask( token_type_ids, device=inputs_embeds.device ) return create_masks_for_generate(**mask_kwargs) @auto_docstring( custom_intro=""" Gemma3TextForSequenceClassification is a text-only sequence classification model that works with Gemma3TextConfig. It uses the generic sequence classification implementation for efficiency and consistency.""" ) class Gemma3TextForSequenceClassification(GenericForSequenceClassification, Gemma3PreTrainedModel): config: Gemma3TextConfig input_modalities = ("text",) class Gemma3ForSequenceClassification(GenericForSequenceClassification, Gemma3PreTrainedModel): def forward( self, input_ids: torch.LongTensor | None = None, pixel_values: torch.FloatTensor | None = None, attention_mask: torch.Tensor | None = None, position_ids: torch.LongTensor | None = None, past_key_values: Cache | None = None, token_type_ids: torch.LongTensor | None = None, inputs_embeds: torch.FloatTensor | None = None, labels: torch.LongTensor | None = None, **kwargs: Unpack[TransformersKwargs], ) -> SequenceClassifierOutputWithPast: return super().forward( input_ids=input_ids, attention_mask=attention_mask, position_ids=position_ids, past_key_values=past_key_values, inputs_embeds=inputs_embeds, pixel_values=pixel_values, token_type_ids=token_type_ids, labels=labels, **kwargs, ) __all__ = [ "Gemma3PreTrainedModel", "Gemma3TextModel", "Gemma3ForCausalLM", "Gemma3ForConditionalGeneration", "Gemma3Model", "Gemma3ForSequenceClassification", "Gemma3TextForSequenceClassification", ]