Source code for easydel.modules.grok_1.modeling_grok_1

# Copyright 2025 The EasyDeL Author @erfanzar (Erfan Zare Chavoshi).
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# Licensed under the Apache License, Version 2.0 (the "License");
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#     https://www.apache.org/licenses/LICENSE-2.0
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from functools import cached_property

import chex
import jax
import jax.numpy as jnp
from eformer import common_types
from eformer.escale import apply_logical_sharding
from ejkernel.types import MaskInfo
from flax import nnx as nn
from jax.ad_checkpoint import checkpoint_name
from jaxtyping import Array, Bool, Float, Int

from easydel.infra.base_module import EasyDeLBaseModule
from easydel.infra.factory import TaskType, register_module
from easydel.infra.loss_utils import auxiliary_load_balancing_loss_func
from easydel.infra.modeling_outputs import AttentionLayerOutput, DecoderLayerOutput, MoeCausalLMOutput, MoeModelOutput
from easydel.infra.utils import auto_remat, block_wise_ffn, get_dot_general_by_bits
from easydel.layers.attention import AttentionModule, FlexibleAttentionModule
from easydel.layers.base_modules import BaseCausalLMModule
from easydel.layers.caching import (
    RaggedPagesCache,
    RaggedPagesCacheView,
    RaggedPagesMetadata,
    TransformerCache,
    TransformerCacheView,
    TransformerMetadata,
)
from easydel.layers.linear import ColumnParallelLinear, RowParallelLinear
from easydel.layers.norms import RMSNorm as FlaxGrok1RMSNorm

from .grok_1_configuration import Grok1Config


[docs]class Grok1Attention(AttentionModule): """Grok-1 Attention module. This module implements the multi-head attention mechanism with rotary position embeddings used in the Grok-1 model. Attributes: config (Grok1Config): Configuration object for the model. layer_index (int): The index of the current layer. dtype (jnp.dtype): Data type for computations. param_dtype (jnp.dtype): Data type for parameters. precision (jax.lax.PrecisionLike): Precision setting for JAX operations. rngs (nn.Rngs): Random number generators. """ def __init__( self, config: Grok1Config, layer_index: int, dtype: jnp.dtype = jnp.bfloat16, param_dtype: jnp.dtype = jnp.bfloat16, precision: jax.lax.PrecisionLike = None, *, rngs: nn.Rngs, ): super().__init__(config=config) self.dtype = dtype self.param_dtype = param_dtype self.precision = precision self.rngs = rngs self.layer_index = layer_index self.hidden_size = config.hidden_size self.head_dim = self.config.hidden_size // self.config.num_attention_heads self.num_key_value_groups = self.config.num_attention_heads // self.config.num_key_value_heads if self.num_key_value_groups == 1: assert self.config.num_attention_heads == self.config.num_key_value_heads self.q_proj = ColumnParallelLinear( config.hidden_size, config.num_attention_heads * self.head_dim, dtype=dtype, param_dtype=param_dtype, use_bias=False, kernel_init=jax.nn.initializers.normal(config.initializer_range), precision=self.precision, rngs=rngs, **get_dot_general_by_bits(config.bits, config.easy_method), ) self.k_proj = ColumnParallelLinear( config.hidden_size, config.num_key_value_heads * self.head_dim, dtype=dtype, param_dtype=param_dtype, use_bias=False, kernel_init=jax.nn.initializers.normal(config.initializer_range), precision=self.precision, rngs=rngs, **get_dot_general_by_bits(config.bits, config.easy_method), ) self.v_proj = ColumnParallelLinear( config.hidden_size, config.num_key_value_heads * self.head_dim, dtype=dtype, param_dtype=param_dtype, use_bias=False, kernel_init=jax.nn.initializers.normal(config.initializer_range), precision=self.precision, rngs=rngs, **get_dot_general_by_bits(config.bits, config.easy_method), ) self.o_proj = RowParallelLinear( config.num_attention_heads * self.head_dim, config.hidden_size, dtype=dtype, param_dtype=param_dtype, use_bias=False, kernel_init=jax.nn.initializers.normal(config.initializer_range), precision=self.precision, rngs=rngs, **get_dot_general_by_bits(config.bits, config.easy_method), ) self.rotary = self.config.get_basic_rope(self.dtype, self.head_dim, self.head_dim, True) self.attention_performer = FlexibleAttentionModule( rngs=rngs, base_config=config, softmax_scale=self.head_dim**-0.5, dropout_prob=config.attention_dropout, ) self.resid_dropout = nn.Dropout(rate=config.resid_pdrop) def _merge_heads(self, hidden_states): """ Merges the attention heads into a single hidden state tensor. Args: hidden_states (chex.Array): The hidden states with separate head dimensions. Returns: chex.Array: The hidden states with merged head dimensions. """ return hidden_states.reshape((*hidden_states.shape[:2], self.hidden_size)) def __call__( self, hidden_states: Float[Array, "batch seq_len hidden_dim"], mask_info: MaskInfo | None, position_ids: Int[Array, "batch seq_len"], mode: common_types.RUNTIME_MODE_TYPES, # type:ignore cache_view: TransformerCacheView | RaggedPagesCacheView | None = None, cache_metadata: TransformerMetadata | RaggedPagesMetadata | None = None, output_attentions: bool = False, frequencies: Float[Array, "seq_len head_dim"] | None = None, ): """Forward pass of the Grok1Attention module. Args: hidden_states (chex.Array): Input hidden states. attention_mask (chex.Array): Mask to apply on the attention scores. position_ids (chex.Array): Position indices for the tokens. causal_mask (chex.Array, optional): Causal mask for ensuring autoregressive behavior. cache_view (tp.Optional[TransformerCacheView | RaggedPagesCacheView], optional): Cache view for key/value states. cache_metadata (tp.Optional[TransformerMetadata | RaggedPagesMetadata], optional): Metadata for cache handling. segment_ids (tp.Optional[chex.Array], optional): Segment IDs for segment-based attention. output_attentions (bool, optional): Whether to return attention weights. fcm_mask (tp.Optional[chex.Array], optional): Forward causal mask. frequencies (tp.Optional[chex.Array], optional): Precomputed rotary frequencies. Returns: tp.Tuple[chex.Array, tp.Optional[chex.Array]]: A tuple containing the attention output and optionally the attention weights. """ batch_size, sequence_length = hidden_states.shape[:2] query_states, key_states, value_states = ( checkpoint_name(self.q_proj(hidden_states), "attn_query"), checkpoint_name(self.k_proj(hidden_states), "attn_key"), checkpoint_name(self.v_proj(hidden_states), "attn_value"), ) query_states = query_states.reshape(batch_size, sequence_length, self.config.num_attention_heads, self.head_dim) key_states = key_states.reshape(batch_size, sequence_length, self.config.num_key_value_heads, self.head_dim) value_states = value_states.reshape(batch_size, sequence_length, self.config.num_key_value_heads, self.head_dim) query_states, key_states, value_states = self.apply_qkv_shardings(query_states, key_states, value_states) query_states, key_states = self.rotary( positions=position_ids, query=query_states, key=key_states, frequencies=frequencies, ) ( key_states, value_states, mask_info, init_attention_bias, cache_view, cache_metadata, ) = self.concatenate( query=query_states, key=key_states, value=value_states, cache_view=cache_view, cache_metadata=cache_metadata, mask_info=mask_info, ) attentions = self.attention_performer.forward( query_states=query_states, key_states=key_states, value_states=value_states, mode=mode, bias=None, cache_metadata=cache_metadata, cache_view=cache_view, init_bias=init_attention_bias, mask_info=mask_info, causal=True, ) attn_output = self.shard_attention_prod(self._merge_heads(attentions.attention_outputs)) attn_output = checkpoint_name(self.o_proj(attn_output), "attn_output") attn_output = self.resid_dropout(attn_output) return AttentionLayerOutput( attention_output=attn_output, attention_weight=attentions.attention_weights if output_attentions else None, cache_view=cache_view, )
[docs]class Grok1BLockSparseMLP(nn.Module): """Grok-1 Block Sparse MLP module. This module implements the specific MLP structure used within the sparse Mixture of Experts layer in the Grok-1 model. Attributes: config (Grok1Config): Configuration object for the model. dtype (jnp.dtype): Data type for computations. param_dtype (jnp.dtype): Data type for parameters. precision (jax.lax.PrecisionLike): Precision setting for JAX operations. rngs (nn.Rngs): Random number generators. """ def __init__( self, config: Grok1Config, dtype: jnp.dtype = jnp.bfloat16, param_dtype: jnp.dtype = jnp.bfloat16, precision: jax.lax.PrecisionLike = None, *, rngs: nn.Rngs, ): super().__init__() self.config = config self.dtype = dtype self.param_dtype = param_dtype self.precision = precision self.rngs = rngs self.linear = ColumnParallelLinear( config.hidden_size, config.intermediate_size, dtype=dtype, param_dtype=param_dtype, use_bias=False, kernel_init=jax.nn.initializers.normal(config.initializer_range), precision=self.precision, rngs=rngs, **get_dot_general_by_bits(config.bits, config.easy_method), ) self.linear_1 = RowParallelLinear( config.intermediate_size, config.hidden_size, dtype=dtype, param_dtype=param_dtype, use_bias=False, kernel_init=jax.nn.initializers.normal(config.initializer_range), precision=self.precision, rngs=rngs, **get_dot_general_by_bits(config.bits, config.easy_method), ) self.linear_v = ColumnParallelLinear( config.hidden_size, config.intermediate_size, dtype=dtype, param_dtype=param_dtype, use_bias=False, kernel_init=jax.nn.initializers.normal(config.initializer_range), precision=self.precision, rngs=rngs, **get_dot_general_by_bits(config.bits, config.easy_method), ) def __call__(self, hidden_states: Float[Array, "batch seq_len hidden_dim"]) -> jnp.ndarray: """Forward pass of the Grok1BLockSparseMLP module. Args: hidden_states (chex.Array): Input hidden states. Returns: chex.Array: Output hidden states after processing through the block sparse MLP. """ hidden_states = apply_logical_sharding( hidden_states, dynamic_axes=common_types.HiddenStateSharding, partition_manager=self.config.partition_manager, ) gate = checkpoint_name(nn.gelu(self.linear(hidden_states)), "mlp_gate") up = checkpoint_name(self.linear_v(hidden_states), "mlp_up") hidden_states = checkpoint_name(self.linear_1(gate * up), "mlp_down") hidden_states = apply_logical_sharding( hidden_states, dynamic_axes=common_types.HiddenStateSharding, partition_manager=self.config.partition_manager, ) return checkpoint_name(hidden_states, "mlp_output")
[docs]class Grok1SparseMoeBlock(nn.Module): """Grok-1 Sparse Mixture of Experts (MoE) block. This module implements the sparse MoE layer used in Grok-1. It routes tokens to a subset of experts based on learned gating weights. Attributes: config (Grok1Config): Configuration object for the model. dtype (jnp.dtype): Data type for computations. param_dtype (jnp.dtype): Data type for parameters. precision (jax.lax.PrecisionLike): Precision setting for JAX operations. rngs (nn.Rngs): Random number generators. """ def __init__( self, config: Grok1Config, dtype: jnp.dtype = jnp.bfloat16, param_dtype: jnp.dtype = jnp.bfloat16, precision: jax.lax.PrecisionLike = None, *, rngs: nn.Rngs, ): super().__init__() self.config = config self.dtype = dtype self.param_dtype = param_dtype self.precision = precision self.rngs = rngs self.gate = ColumnParallelLinear( self.config.hidden_size, self.config.num_experts, use_bias=False, dtype=dtype, param_dtype=param_dtype, precision=precision, kernel_init=nn.initializers.normal(), rngs=rngs, ) self.experts = [ Grok1BLockSparseMLP( config=config, dtype=dtype, param_dtype=param_dtype, precision=precision, rngs=rngs, ) for i in range(self.config.num_experts) ] def __call__(self, hidden_states: Float[Array, "batch seq_len hidden_dim"]) -> tuple[chex.Array, chex.Array]: """Forward pass of the Grok1SparseMoeBlock. Args: hidden_states (chex.Array): Input hidden states. Returns: tp.Tuple[chex.Array, chex.Array]: A tuple containing the output hidden states and the router logits. """ hidden_states = apply_logical_sharding( hidden_states, dynamic_axes=common_types.HiddenStateSharding, partition_manager=self.config.partition_manager, ) router_logits = checkpoint_name( self.gate(hidden_states).astype(jnp.promote_types(self.dtype, jnp.float32)), "moe_router_logits" ) routing_weights, selected_experts = jax.lax.top_k(router_logits, k=self.config.num_experts_per_tok) routing_weights = jax.nn.softmax(routing_weights.astype(jnp.promote_types(self.dtype, jnp.float32)), axis=-1) final_hidden_state = jnp.zeros_like(hidden_states) for index in range(self.config.num_experts): expert_layer_output = ( block_wise_ffn( self.experts[index], hidden_states, self.config.scan_mlp_chunk_size, ) if self.config.use_scan_mlp else self.experts[index](hidden_states) ) expert_layer_output_exp = ( jnp.sum( jnp.multiply( selected_experts == index, routing_weights, ), axis=-1, )[:, :, None] * expert_layer_output ) final_hidden_state += expert_layer_output_exp return (checkpoint_name(final_hidden_state, "moe_expert_output"), router_logits)
[docs]class Grok1DecoderLayer(nn.Module): """Grok-1 Transformer Decoder Layer. This module represents a single decoder layer in the Grok-1 model, combining self-attention and a sparse MoE block with residual connections and layer normalization. Attributes: config (Grok1Config): Configuration object for the model. dtype (jnp.dtype): Data type for computations. param_dtype (jnp.dtype): Data type for parameters. precision (jax.lax.PrecisionLike): Precision setting for JAX operations. rngs (nn.Rngs): Random number generators. """ def __init__( self, config: Grok1Config, layer_index: int, dtype: jnp.dtype = jnp.bfloat16, param_dtype: jnp.dtype = jnp.bfloat16, precision: jax.lax.PrecisionLike = None, *, rngs: nn.Rngs, ): super().__init__() self.config = config self.layer_index = layer_index self.dtype = dtype self.param_dtype = param_dtype self.precision = precision self.rngs = rngs attn_block = Grok1Attention mlp_block = Grok1SparseMoeBlock attn_block, mlp_block = auto_remat( attn_block, mlp_block, policy=config.gradient_checkpointing, save_names=config.gradient_checkpointing_targets, exclude_names=config.gradient_checkpointing_targets, ) self.attn = attn_block( config=self.config, layer_index=layer_index, dtype=dtype, param_dtype=param_dtype, precision=precision, rngs=rngs, ) self.moe_block = mlp_block( config=config, dtype=dtype, param_dtype=param_dtype, precision=precision, rngs=rngs, ) self.pre_attn_norm = FlaxGrok1RMSNorm( dim=self.config.hidden_size, eps=self.config.rms_norm_eps, dtype=dtype, param_dtype=param_dtype, rngs=rngs, ) self.post_attn_norm = FlaxGrok1RMSNorm( dim=self.config.hidden_size, eps=self.config.rms_norm_eps, dtype=dtype, param_dtype=param_dtype, rngs=rngs, ) self.pre_moe_norm = FlaxGrok1RMSNorm( dim=self.config.hidden_size, eps=self.config.rms_norm_eps, dtype=dtype, param_dtype=param_dtype, rngs=rngs, ) self.post_moe_norm = FlaxGrok1RMSNorm( dim=self.config.hidden_size, eps=self.config.rms_norm_eps, dtype=dtype, param_dtype=param_dtype, rngs=rngs, ) def __call__( self, hidden_states: Float[Array, "batch seq_len hidden_dim"], mask_info: MaskInfo, position_ids: Int[Array, "batch seq_len"], mode: common_types.RUNTIME_MODE_TYPES, # type:ignore cache_view: TransformerCacheView | RaggedPagesCacheView | None = None, cache_metadata: TransformerMetadata | RaggedPagesMetadata | None = None, output_attentions: bool = False, output_router_logits: bool = False, frequencies: Float[Array, "seq_len head_dim"] | None = None, ) -> DecoderLayerOutput: """Forward pass of the Grok1DecoderLayer module. Args: hidden_states (chex.Array): Input hidden states. attention_mask (chex.Array): Mask to apply on the attention scores. position_ids (chex.Array): Position indices for the tokens. causal_mask (chex.Array, optional): Causal mask for ensuring autoregressive behavior. cache_view (tp.Optional[TransformerCacheView | RaggedPagesCacheView], optional): Cache view for key/value states. cache_metadata (tp.Optional[TransformerMetadata | RaggedPagesMetadata], optional): Metadata for cache handling. segment_ids (tp.Optional[chex.Array], optional): Segment IDs for segment-based attention. output_attentions (bool, optional): Whether to return attention weights. Defaults to False. output_router_logits (bool, optional): Whether to return router logits from the MoE layer. Defaults to False. fcm_mask (tp.Optional[chex.Array], optional): Forward causal mask. Defaults to None. frequencies (tp.Optional[chex.Array], optional): Precomputed rotary frequencies. Returns: tp.Tuple[chex.Array, tp.Optional[chex.Array], tp.Optional[chex.Array]]: A tuple containing the output hidden states, optionally the attention weights, and optionally the router logits. """ residual = hidden_states hidden_states = self.pre_attn_norm(hidden_states) attn_outputs = self.attn( hidden_states, mask_info, position_ids, mode, cache_view, cache_metadata, output_attentions, frequencies, ) hidden_states = attn_outputs.attention_output hidden_states = self.post_attn_norm(hidden_states) hidden_states = checkpoint_name(residual + hidden_states, "residual") residual = hidden_states hidden_states = self.pre_moe_norm(hidden_states) hidden_states, router_logits = self.moe_block(hidden_states) hidden_states = self.post_moe_norm(hidden_states) hidden_states = checkpoint_name(residual + hidden_states, "residual") hidden_states = checkpoint_name(hidden_states, "layer_output") return DecoderLayerOutput( hidden_states=hidden_states, attention_weight=attn_outputs.attention_weight, router_logits=router_logits if output_router_logits else None, cache_view=attn_outputs.cache_view, )
[docs]@register_module(TaskType.BASE_MODULE, config=Grok1Config, model_type="grok-1") class Grok1Model(EasyDeLBaseModule): """Grok-1 model implementation. This class implements the main Grok-1 transformer model architecture, consisting of an embedding layer, multiple Grok1DecoderLayer layers (with sparse MoE), and a final RMS normalization layer. Attributes: config (Grok1Config): Configuration object for the model. dtype (jnp.dtype): Data type for computations. param_dtype (jnp.dtype): Data type for parameters. precision (jax.lax.PrecisionLike): Precision setting for JAX operations. rngs (nn.Rngs): Random number generators. """ def __init__( self, config: Grok1Config, dtype: jnp.dtype = jnp.bfloat16, param_dtype: jnp.dtype = jnp.bfloat16, precision: jax.lax.PrecisionLike = None, *, rngs: nn.Rngs, ): super().__init__( config=config, dtype=dtype, param_dtype=param_dtype, precision=precision, rngs=rngs, ) embed_block = auto_remat( nn.Embed, policy=config.gradient_checkpointing, save_names=config.gradient_checkpointing_targets, exclude_names=config.gradient_checkpointing_targets, ) self.embed_tokens = embed_block( self.config.vocab_size, self.config.hidden_size, dtype=dtype, param_dtype=param_dtype, rngs=rngs, ) self.layers = [ Grok1DecoderLayer( layer_index=layer_index, config=config, dtype=dtype, param_dtype=param_dtype, precision=precision, rngs=rngs, ) for layer_index in range(self.config.num_hidden_layers) ] self.norm = FlaxGrok1RMSNorm( self.config.hidden_size, eps=self.config.rms_norm_eps, dtype=dtype, param_dtype=param_dtype, rngs=rngs, ) @cached_property def frequencies(self): return self.config.get_basic_frequencies( head_size=self.config.hidden_size // self.config.num_attention_heads, base=self.config.rope_theta, ) def __call__( self, input_ids: Int[Array, "batch seq_len"] | None = None, inputs_embeds: Float[Array, "batch seq_len hidden_dim"] | None = None, attention_mask: Bool[Array, "batch seq_len"] | None = None, mask_info: MaskInfo | None = None, position_ids: Int[Array, "batch seq_len"] | None = None, output_attentions: bool | None = None, output_hidden_states: bool | None = None, output_router_logits: bool | None = None, mode: common_types.RUNTIME_MODE_TYPES | None = None, # type:ignore past_key_values: TransformerCache | RaggedPagesCache | None = None, cache_metadata: TransformerMetadata | RaggedPagesMetadata | None = None, ) -> MoeModelOutput: """Forward pass through the Grok1Model. Args: input_ids (chex.Array, optional): Input token IDs, shape (batch_size, sequence_length). inputs_embeds (chex.Array, optional): Input embeddings, shape (batch_size, sequence_length, hidden_size). attention_mask (chex.Array, optional): Mask to avoid attention on padding tokens. position_ids (chex.Array, optional): Indices of positions of each input sequence token. segment_ids (chex.Array, optional): Segment token indices for segment embeddings. output_attentions (bool, optional): Whether to return attention weights. output_hidden_states (bool, optional): Whether to return hidden states of all layers. output_router_logits (bool, optional): Whether to return router logits from MoE layers. past_key_values (TransformerCache | RaggedPagesCache, optional): Cache containing precomputed key/value states. cache_metadata (TransformerMetadata | RaggedPagesMetadata, optional): Metadata for cache handling. Returns: MoeModelOutput: Model outputs (last hidden state, optional hidden states, optional attentions, optional router logits) """ output_attentions = output_attentions if output_attentions is not None else self.config.output_attentions output_router_logits = ( output_router_logits if output_router_logits is not None else self.config.output_router_logits ) output_hidden_states = ( output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states ) all_hidden_states = () if output_hidden_states else None all_self_attns = () if output_attentions else None all_router_logits = () if output_router_logits else None if output_router_logits is None: output_router_logits = self.config.output_router_logits if (input_ids is None) ^ (inputs_embeds is not None): raise ValueError( "You cannot specify both input_ids and inputs_embeds at the same time, and must specify either one" ) if inputs_embeds is None: inputs_embeds = checkpoint_name(self.embed_tokens(input_ids.astype("i4")), "embeddings") sequence_length = inputs_embeds.shape[1] mask_info = MaskInfo.dynamic_init( mask_info=mask_info, input_ids=input_ids, inputs_embeds=inputs_embeds, attention_mask=attention_mask, ) if position_ids is None: position_ids = mask_info.q_position_ids hidden_states = inputs_embeds if mode is None: mode = ( common_types.MODE_DECODE if sequence_length == 1 and past_key_values is not None else common_types.MODE_TRAIN ) if past_key_values is None: past_key_values = TransformerCache.init_empty(len(self.layers)) hidden_states = apply_logical_sharding( hidden_states, dynamic_axes=common_types.HiddenStateSharding, partition_manager=self.config.partition_manager, ) for idx, block in enumerate(self.layers): if output_hidden_states: all_hidden_states += (hidden_states,) layer_outputs = block( hidden_states=hidden_states, mask_info=mask_info, position_ids=position_ids, output_attentions=output_attentions, output_router_logits=output_router_logits, mode=mode, cache_view=past_key_values.view[idx], cache_metadata=cache_metadata, frequencies=self.frequencies, ) hidden_states = layer_outputs.hidden_states if output_attentions: all_self_attns += (layer_outputs.attention_weight,) if output_router_logits: all_router_logits += (layer_outputs.router_logits,) past_key_values[idx] = layer_outputs.cache_view hidden_states = self.norm(hidden_states) hidden_states = checkpoint_name(hidden_states, "model_output") if output_hidden_states: all_hidden_states += (hidden_states,) return MoeModelOutput( last_hidden_state=hidden_states, hidden_states=all_hidden_states, attentions=all_self_attns, router_logits=all_router_logits, past_key_values=past_key_values, )
[docs] def get_encoder(self): """ Returns the encoder part of the model's graph definition. Decoder-Only models don't have an encoder. """ raise NotImplementedError("This is a decoder-only model and does not have an encoder.")
[docs] def get_decoder(self): """ Returns the decoder part of the model's graph definition. """ return self
[docs] def get_lm_head(self): """ Returns the language model head of the module. Base Models don't have a Language Model Head. """ raise NotImplementedError("The base model does not have a language model head.")
[docs] def get_embedding(self): """ Returns the embedding layer of the module. """ return self.embed_tokens
[docs]@register_module(TaskType.CAUSAL_LM, config=Grok1Config, model_type="grok-1") class Grok1ForCausalLM(BaseCausalLMModule[Grok1Model, Grok1Config]): """Grok-1 model with a language modeling head. This model extends the base Grok1Model by adding a linear layer on top to predict the next token in a sequence, making it suitable for causal language modeling tasks. It also includes handling for the Mixture of Experts auxiliary loss. Attributes: config (Grok1Config): Configuration object for the model. dtype (jnp.dtype): Data type for computations. param_dtype (jnp.dtype): Data type for parameters. precision (jax.lax.PrecisionLike): Precision setting for JAX operations. rngs (nn.Rngs): Random number generators. """ _task_type = TaskType.CAUSAL_LM _model_type = "grok-1" _config_class = Grok1Config def __init__( self, config: Grok1Config, dtype: jnp.dtype = jnp.bfloat16, param_dtype: jnp.dtype = jnp.bfloat16, precision: jax.lax.PrecisionLike = None, *, rngs: nn.Rngs, ): super().__init__( config=config, base_model_class=Grok1Model, base_model_name="model", dtype=dtype, param_dtype=param_dtype, precision=precision, rngs=rngs, lm_head_bias=False, router_aux_loss_coef=getattr(config, "router_aux_loss_coef", None), ) self.output_multiplier_scale = self.config.output_multiplier_scale def __call__( self, input_ids: Int[Array, "batch seq_len"] | None = None, inputs_embeds: Float[Array, "batch seq_len hidden_dim"] | None = None, attention_mask: Bool[Array, "batch seq_len"] | None = None, mask_info: MaskInfo | None = None, position_ids: Int[Array, "batch seq_len"] | None = None, output_attentions: bool | None = None, output_hidden_states: bool | None = None, output_router_logits: bool | None = None, mode: common_types.RUNTIME_MODE_TYPES | None = None, past_key_values: TransformerCache | RaggedPagesCache | None = None, cache_metadata: TransformerMetadata | RaggedPagesMetadata | None = None, apply_lm_head: bool = True, ) -> MoeCausalLMOutput: """Forward pass through the Grok1ForCausalLM model. Args: input_ids (chex.Array, optional): Input token IDs, shape (batch_size, sequence_length). inputs_embeds (chex.Array, optional): Input embeddings, shape (batch_size, sequence_length, hidden_size). attention_mask (chex.Array, optional): Mask to avoid attention on padding tokens. position_ids (chex.Array, optional): Indices of positions of each input sequence token. output_attentions (bool, optional): Whether to return attention weights. output_hidden_states (bool, optional): Whether to return hidden states of all layers. output_router_logits (bool, optional): Whether to return router logits from MoE layers. past_key_values (TransformerCache | RaggedPagesCache, optional): Cache containing precomputed key/value states. cache_metadata (TransformerMetadata | RaggedPagesMetadata, optional): Metadata for cache handling. Returns: MoeCausalLMOutput: Model outputs (logits, optional auxiliary loss, optional hidden states, optional attentions, optional router logits) """ return self.forward_moe( input_ids=input_ids, inputs_embeds=inputs_embeds, attention_mask=attention_mask, mask_info=mask_info, position_ids=position_ids, mode=mode, past_key_values=past_key_values, cache_metadata=cache_metadata, apply_lm_head=apply_lm_head, output_attentions=output_attentions, output_hidden_states=output_hidden_states, output_router_logits=output_router_logits, aux_loss_fn=self._compute_aux_loss, ) def _compute_aux_loss(self, outputs, attention_mask): """Compute auxiliary loss for load balancing.""" if outputs.router_logits is None: return None aux_loss = auxiliary_load_balancing_loss_func( gate_logits=outputs.router_logits, num_experts=self.config.num_experts, top_k=self.config.num_experts_per_tok, attention_mask=attention_mask, ) return aux_loss + (aux_loss * self.config.router_aux_loss_coef)
[docs] def apply_lm_head(self, hidden_states: Float[Array, "batch seq_len hidden_dim"]) -> chex.Array: """Apply LM head with Grok-1's output multiplier scale.""" lm_logits = super().apply_lm_head(hidden_states) lm_logits = lm_logits * self.output_multiplier_scale return lm_logits