Module neuralops.attentions.regla_attention

Refined Gated Linear Attention (ReGLA) – Production-Hardened (v2).

Functions

def apply_rotary_pos_emb(q: torch.Tensor, k: torch.Tensor, cos: torch.Tensor, sin: torch.Tensor) ‑> tuple[torch.Tensor, torch.Tensor]
Expand source code
def apply_rotary_pos_emb(
    q: torch.Tensor,
    k: torch.Tensor,
    cos: torch.Tensor,
    sin: torch.Tensor,
) -> tuple[torch.Tensor, torch.Tensor]:
    if cos is None or sin is None:
        return q, k

    if cos.dim() == 2:
        cos = cos.unsqueeze(0).unsqueeze(0)
        sin = sin.unsqueeze(0).unsqueeze(0)
    elif cos.dim() == 3:
        cos = cos.unsqueeze(1)
        sin = sin.unsqueeze(1)

    while cos.dim() < q.dim():
        cos = cos.unsqueeze(0)
        sin = sin.unsqueeze(0)

    if cos.shape[-2] != q.shape[-2]:
        raise ValueError(f"RoPE seq len mismatch: cos {cos.shape[-2]} vs q {q.shape[-2]}")

    rotary_dim = cos.shape[-1]
    head_dim = q.shape[-1]

    if rotary_dim <= head_dim:
        q_rot, q_pass = q[..., :rotary_dim], q[..., rotary_dim:]
        k_rot, k_pass = k[..., :rotary_dim], k[..., rotary_dim:]
        cos_q = cos.to(q_rot.dtype)
        sin_q = sin.to(q_rot.dtype)
        cos_k = cos.to(k_rot.dtype)
        sin_k = sin.to(k_rot.dtype)
        q_rot_embed = (q_rot * cos_q) + (_rotate_half(q_rot) * sin_q)
        k_rot_embed = (k_rot * cos_k) + (_rotate_half(k_rot) * sin_k)
        q = torch.cat([q_rot_embed, q_pass], dim=-1) if q_pass.numel() > 0 else q_rot_embed
        k = torch.cat([k_rot_embed, k_pass], dim=-1) if k_pass.numel() > 0 else k_rot_embed
    else:
        cos_cut = cos[..., :head_dim].to(q.dtype)
        sin_cut = sin[..., :head_dim].to(q.dtype)
        q = (q * cos_cut) + (_rotate_half(q) * sin_cut)
        cos_k = cos[..., :head_dim].to(k.dtype)
        sin_k = sin[..., :head_dim].to(k.dtype)
        k = (k * cos_k) + (_rotate_half(k) * sin_k)

    return q, k
def inject_regla(model: torch.nn.modules.module.Module | None = None,
layer: torch.nn.modules.module.Module | None = None,
model_config: Any = None,
comp_config: Any = None,
layer_idx: int = 0,
total_layers: int = 12,
old_attn: torch.nn.modules.module.Module | None = None,
**kwargs: Any)
Expand source code
@ATTENTION_REGISTRY.register("regla")
@ATTENTION_REGISTRY.register("regla_attention")
@ATTENTION_REGISTRY.register("regla_inject")
@ATTENTION_REGISTRY.register("inject_regla")
def inject_regla(
    model: nn.Module | None = None,
    layer: nn.Module | None = None,
    model_config: Any = None,
    comp_config: Any = None,
    layer_idx: int = 0,
    total_layers: int = 12,
    old_attn: nn.Module | None = None,
    _depth: int = 0,
    **kwargs: Any,
):
    if _depth > 8:
        logger.warning("inject_regla: max recursion depth exceeded.")
        return None

    target = layer if layer is not None else model
    if target is None:
        target = kwargs.get("model", kwargs.get("layer"))
    if target is None:
        return None

    cfg = model_config if model_config is not None else getattr(target, "config", None)

    # Whole model traversal
    layer_list = None
    if hasattr(target, "distilbert") and hasattr(target.distilbert, "transformer"):
        layer_list = target.distilbert.transformer.layer
    elif hasattr(target, "roberta") and hasattr(target.roberta, "encoder"):
        layer_list = target.roberta.encoder.layer
    elif hasattr(target, "transformer") and hasattr(target.transformer, "h"):
        layer_list = target.transformer.h
    elif hasattr(target, "h") and isinstance(target.h, (nn.ModuleList, list)):
        layer_list = target.h
    elif hasattr(target, "model") and hasattr(target.model, "layers"):
        layer_list = target.model.layers
    elif hasattr(target, "encoder") and hasattr(target.encoder, "layer"):
        layer_list = target.encoder.layer
    elif (
        hasattr(target, "bert")
        and hasattr(target.bert, "encoder")
        and hasattr(target.bert.encoder, "layer")
    ):
        layer_list = target.bert.encoder.layer
    elif hasattr(target, "layers") and isinstance(target.layers, (nn.ModuleList, list)):
        layer_list = target.layers

    if layer_list is not None:
        num_injected = 0
        tot = len(layer_list)
        for idx, lyr in enumerate(layer_list):
            res = inject_regla(
                layer=lyr,
                model_config=cfg,
                comp_config=comp_config,
                layer_idx=idx,
                total_layers=tot,
                _depth=_depth + 1,
                **kwargs,
            )
            if res is not None:
                num_injected += 1
        return target if num_injected > 0 else None

    # Single layer injection
    try:
        src_attn = old_attn
        if src_attn is None:
            for attr in ("attention", "self_attn", "attn", "self"):
                if hasattr(target, attr):
                    cand = getattr(target, attr)
                    if isinstance(cand, nn.Module) and cand is not target:
                        # RE-18: pass the OUTER container (cand) so copy_weights
                        # can extract output projection for nested models.
                        src_attn = cand
                        break
        if src_attn is None:
            src_attn = target

        if isinstance(src_attn, ReGLAAttention) or "ReGLA" in src_attn.__class__.__name__:
            return None

        c_name = src_attn.__class__.__name__
        if "DeltaNet" in c_name or "LinearAttention" in c_name:
            return None

        if cfg is None and hasattr(src_attn, "config"):
            cfg = src_attn.config

        hidden_size = (
            kwargs.get("hidden_size")
            or getattr(src_attn, "hidden_size", None)
            or getattr(src_attn, "embed_dim", None)
            or (
                src_attn.q_proj.in_features
                if hasattr(src_attn, "q_proj") and hasattr(src_attn.q_proj, "in_features")
                else None
            )
            or (
                src_attn.query.in_features
                if hasattr(src_attn, "query") and hasattr(src_attn.query, "in_features")
                else None
            )
            or (
                src_attn.q_lin.in_features
                if hasattr(src_attn, "q_lin") and hasattr(src_attn.q_lin, "in_features")
                else None
            )
            or (target.in_features if hasattr(target, "in_features") else None)
            or _cfg_get(cfg, "hidden_size", 768)
        )
        num_heads = (
            kwargs.get("num_heads")
            or kwargs.get("num_attention_heads")
            or getattr(src_attn, "num_heads", None)
            or getattr(src_attn, "num_attention_heads", None)
            or _cfg_get(cfg, "num_attention_heads", 12)
        )

        # RE-19: propagate kernel_size, chunk_size, rank from comp_config
        attn_kwargs = {}
        if comp_config is not None:
            for key in ("kernel_size", "chunk_size", "rank"):
                val = getattr(comp_config, key, None)
                if val is not None:
                    attn_kwargs[key] = val

        kwargs.pop("hidden_size", None)
        kwargs.pop("num_heads", None)
        kwargs.pop("d_model", None)
        new_attn = ReGLAAttention(
            config=cfg,
            pretrained_attn=src_attn if src_attn is not target else None,
            hidden_size=hidden_size,
            num_heads=num_heads,
            **attn_kwargs,
            **kwargs,
        )

        p = next(src_attn.parameters(), None)
        if p is not None:
            new_attn.to(device=p.device, dtype=p.dtype)

        # RE-20: ensure out_proj is Identity when attaching to nested encoder
        if hasattr(target, "attention"):
            if hasattr(target.attention, "self"):
                new_attn.is_nested_encoder = True
                if not isinstance(new_attn.out_proj, nn.Identity):
                    new_attn.out_proj = nn.Identity()
                target.attention.self = new_attn
            else:
                new_attn.is_nested_encoder = False
                target.attention = new_attn
        elif hasattr(target, "self_attn"):
            new_attn.is_nested_encoder = False
            target.self_attn = new_attn
        elif hasattr(target, "attn"):
            new_attn.is_nested_encoder = False
            target.attn = new_attn
        elif hasattr(target, "self"):
            new_attn.is_nested_encoder = True
            if not isinstance(new_attn.out_proj, nn.Identity):
                new_attn.out_proj = nn.Identity()
            target.self = new_attn

        return new_attn
    except Exception as e:
        logger.exception("inject_regla failed at layer %d: %s", layer_idx, e)
        return None
def inject_regla_attention(model: torch.nn.modules.module.Module | None = None,
layer: torch.nn.modules.module.Module | None = None,
model_config: Any = None,
comp_config: Any = None,
layer_idx: int = 0,
total_layers: int = 12,
old_attn: torch.nn.modules.module.Module | None = None,
**kwargs: Any)
Expand source code
@ATTENTION_REGISTRY.register("regla")
@ATTENTION_REGISTRY.register("regla_attention")
@ATTENTION_REGISTRY.register("regla_inject")
@ATTENTION_REGISTRY.register("inject_regla")
def inject_regla(
    model: nn.Module | None = None,
    layer: nn.Module | None = None,
    model_config: Any = None,
    comp_config: Any = None,
    layer_idx: int = 0,
    total_layers: int = 12,
    old_attn: nn.Module | None = None,
    _depth: int = 0,
    **kwargs: Any,
):
    if _depth > 8:
        logger.warning("inject_regla: max recursion depth exceeded.")
        return None

    target = layer if layer is not None else model
    if target is None:
        target = kwargs.get("model", kwargs.get("layer"))
    if target is None:
        return None

    cfg = model_config if model_config is not None else getattr(target, "config", None)

    # Whole model traversal
    layer_list = None
    if hasattr(target, "distilbert") and hasattr(target.distilbert, "transformer"):
        layer_list = target.distilbert.transformer.layer
    elif hasattr(target, "roberta") and hasattr(target.roberta, "encoder"):
        layer_list = target.roberta.encoder.layer
    elif hasattr(target, "transformer") and hasattr(target.transformer, "h"):
        layer_list = target.transformer.h
    elif hasattr(target, "h") and isinstance(target.h, (nn.ModuleList, list)):
        layer_list = target.h
    elif hasattr(target, "model") and hasattr(target.model, "layers"):
        layer_list = target.model.layers
    elif hasattr(target, "encoder") and hasattr(target.encoder, "layer"):
        layer_list = target.encoder.layer
    elif (
        hasattr(target, "bert")
        and hasattr(target.bert, "encoder")
        and hasattr(target.bert.encoder, "layer")
    ):
        layer_list = target.bert.encoder.layer
    elif hasattr(target, "layers") and isinstance(target.layers, (nn.ModuleList, list)):
        layer_list = target.layers

    if layer_list is not None:
        num_injected = 0
        tot = len(layer_list)
        for idx, lyr in enumerate(layer_list):
            res = inject_regla(
                layer=lyr,
                model_config=cfg,
                comp_config=comp_config,
                layer_idx=idx,
                total_layers=tot,
                _depth=_depth + 1,
                **kwargs,
            )
            if res is not None:
                num_injected += 1
        return target if num_injected > 0 else None

    # Single layer injection
    try:
        src_attn = old_attn
        if src_attn is None:
            for attr in ("attention", "self_attn", "attn", "self"):
                if hasattr(target, attr):
                    cand = getattr(target, attr)
                    if isinstance(cand, nn.Module) and cand is not target:
                        # RE-18: pass the OUTER container (cand) so copy_weights
                        # can extract output projection for nested models.
                        src_attn = cand
                        break
        if src_attn is None:
            src_attn = target

        if isinstance(src_attn, ReGLAAttention) or "ReGLA" in src_attn.__class__.__name__:
            return None

        c_name = src_attn.__class__.__name__
        if "DeltaNet" in c_name or "LinearAttention" in c_name:
            return None

        if cfg is None and hasattr(src_attn, "config"):
            cfg = src_attn.config

        hidden_size = (
            kwargs.get("hidden_size")
            or getattr(src_attn, "hidden_size", None)
            or getattr(src_attn, "embed_dim", None)
            or (
                src_attn.q_proj.in_features
                if hasattr(src_attn, "q_proj") and hasattr(src_attn.q_proj, "in_features")
                else None
            )
            or (
                src_attn.query.in_features
                if hasattr(src_attn, "query") and hasattr(src_attn.query, "in_features")
                else None
            )
            or (
                src_attn.q_lin.in_features
                if hasattr(src_attn, "q_lin") and hasattr(src_attn.q_lin, "in_features")
                else None
            )
            or (target.in_features if hasattr(target, "in_features") else None)
            or _cfg_get(cfg, "hidden_size", 768)
        )
        num_heads = (
            kwargs.get("num_heads")
            or kwargs.get("num_attention_heads")
            or getattr(src_attn, "num_heads", None)
            or getattr(src_attn, "num_attention_heads", None)
            or _cfg_get(cfg, "num_attention_heads", 12)
        )

        # RE-19: propagate kernel_size, chunk_size, rank from comp_config
        attn_kwargs = {}
        if comp_config is not None:
            for key in ("kernel_size", "chunk_size", "rank"):
                val = getattr(comp_config, key, None)
                if val is not None:
                    attn_kwargs[key] = val

        kwargs.pop("hidden_size", None)
        kwargs.pop("num_heads", None)
        kwargs.pop("d_model", None)
        new_attn = ReGLAAttention(
            config=cfg,
            pretrained_attn=src_attn if src_attn is not target else None,
            hidden_size=hidden_size,
            num_heads=num_heads,
            **attn_kwargs,
            **kwargs,
        )

        p = next(src_attn.parameters(), None)
        if p is not None:
            new_attn.to(device=p.device, dtype=p.dtype)

        # RE-20: ensure out_proj is Identity when attaching to nested encoder
        if hasattr(target, "attention"):
            if hasattr(target.attention, "self"):
                new_attn.is_nested_encoder = True
                if not isinstance(new_attn.out_proj, nn.Identity):
                    new_attn.out_proj = nn.Identity()
                target.attention.self = new_attn
            else:
                new_attn.is_nested_encoder = False
                target.attention = new_attn
        elif hasattr(target, "self_attn"):
            new_attn.is_nested_encoder = False
            target.self_attn = new_attn
        elif hasattr(target, "attn"):
            new_attn.is_nested_encoder = False
            target.attn = new_attn
        elif hasattr(target, "self"):
            new_attn.is_nested_encoder = True
            if not isinstance(new_attn.out_proj, nn.Identity):
                new_attn.out_proj = nn.Identity()
            target.self = new_attn

        return new_attn
    except Exception as e:
        logger.exception("inject_regla failed at layer %d: %s", layer_idx, e)
        return None

Classes

class LoRALinear (in_features: int,
out_features: int,
bias: bool = True,
lora_rank: int = 16,
lora_alpha: float = 32.0,
freeze_base: bool = False,
device: torch.device | None = None,
dtype: torch.dtype | None = None)
Expand source code
class LoRALinear(nn.Module):
    def __init__(
        self,
        in_features: int,
        out_features: int,
        bias: bool = True,
        lora_rank: int = 16,
        lora_alpha: float = 32.0,
        freeze_base: bool = False,
        device: torch.device | None = None,
        dtype: torch.dtype | None = None,
    ) -> None:
        super().__init__()
        factory_kwargs = {"device": device, "dtype": dtype}
        self.in_features = int(in_features)
        self.out_features = int(out_features)
        self.lora_rank = int(lora_rank) if lora_rank and lora_rank > 0 else 0
        self.lora_alpha = float(lora_alpha)
        self.lora_scaling = (self.lora_alpha / self.lora_rank) if self.lora_rank > 0 else 1.0
        self.freeze_base = freeze_base

        self.weight = nn.Parameter(torch.empty((out_features, in_features), **factory_kwargs))
        if bias:
            self.bias = nn.Parameter(torch.empty(out_features, **factory_kwargs))
        else:
            self.register_parameter("bias", None)

        if self.lora_rank > 0:
            self.lora_A = nn.Parameter(torch.empty((self.lora_rank, in_features), **factory_kwargs))
            self.lora_B = nn.Parameter(
                torch.empty((out_features, self.lora_rank), **factory_kwargs)
            )
        else:
            self.register_parameter("lora_A", None)
            self.register_parameter("lora_B", None)

        self.reset_parameters()
        if freeze_base:
            self.freeze_base_weights()

    def reset_parameters(self) -> None:
        nn.init.kaiming_uniform_(self.weight, a=math.sqrt(5))
        if self.bias is not None:
            fan_in, _ = nn.init._calculate_fan_in_and_fan_out(self.weight)
            bound = 1 / math.sqrt(fan_in) if fan_in > 0 else 0
            nn.init.uniform_(self.bias, -bound, bound)
        if self.lora_rank > 0 and self.lora_A is not None:
            nn.init.kaiming_uniform_(self.lora_A, a=math.sqrt(5))
            self.lora_A.requires_grad = True
        if self.lora_rank > 0 and self.lora_B is not None:
            nn.init.zeros_(self.lora_B)
            self.lora_B.requires_grad = True

    def freeze_base_weights(self) -> None:
        self.weight.requires_grad = False
        if self.bias is not None:
            self.bias.requires_grad = False
        if self.lora_rank > 0:
            if self.lora_A is not None:
                self.lora_A.requires_grad = True
            if self.lora_B is not None:
                self.lora_B.requires_grad = True

    def forward(self, x: torch.Tensor) -> torch.Tensor:
        target_dtype = x.dtype
        w = self.weight.to(target_dtype) if self.weight.dtype != target_dtype else self.weight
        b = (
            self.bias.to(target_dtype)
            if (self.bias is not None and self.bias.dtype != target_dtype)
            else self.bias
        )
        out = F.linear(x, w, b)
        if self.lora_rank > 0 and self.lora_A is not None and self.lora_B is not None:
            a = self.lora_A.to(target_dtype) if self.lora_A.dtype != target_dtype else self.lora_A
            bb = self.lora_B.to(target_dtype) if self.lora_B.dtype != target_dtype else self.lora_B
            lora_out = F.linear(F.linear(x, a), bb) * self.lora_scaling
            out = out + lora_out
        return out.to(target_dtype)

Base class for all neural network modules.

Your models should also subclass this class.

Modules can also contain other Modules, allowing them to be nested in a tree structure. You can assign the submodules as regular attributes::

import torch.nn as nn
import torch.nn.functional as F


class Model(nn.Module):
    def __init__(self) -> None:
        super().__init__()
        self.conv1 = nn.Conv2d(1, 20, 5)
        self.conv2 = nn.Conv2d(20, 20, 5)

    def forward(self, x):
        x = F.relu(self.conv1(x))
        return F.relu(self.conv2(x))

Submodules assigned in this way will be registered, and will also have their parameters converted when you call :meth:to, etc.

Note

As per the example above, an __init__() call to the parent class must be made before assignment on the child.

:ivar training: Boolean represents whether this module is in training or evaluation mode. :vartype training: bool

Initialize internal Module state, shared by both nn.Module and ScriptModule.

Ancestors

  • torch.nn.modules.module.Module

Methods

def forward(self, x: torch.Tensor) ‑> torch.Tensor
Expand source code
def forward(self, x: torch.Tensor) -> torch.Tensor:
    target_dtype = x.dtype
    w = self.weight.to(target_dtype) if self.weight.dtype != target_dtype else self.weight
    b = (
        self.bias.to(target_dtype)
        if (self.bias is not None and self.bias.dtype != target_dtype)
        else self.bias
    )
    out = F.linear(x, w, b)
    if self.lora_rank > 0 and self.lora_A is not None and self.lora_B is not None:
        a = self.lora_A.to(target_dtype) if self.lora_A.dtype != target_dtype else self.lora_A
        bb = self.lora_B.to(target_dtype) if self.lora_B.dtype != target_dtype else self.lora_B
        lora_out = F.linear(F.linear(x, a), bb) * self.lora_scaling
        out = out + lora_out
    return out.to(target_dtype)

Define the computation performed at every call.

Should be overridden by all subclasses.

Note

Although the recipe for forward pass needs to be defined within this function, one should call the :class:Module instance afterwards instead of this since the former takes care of running the registered hooks while the latter silently ignores them.

def freeze_base_weights(self) ‑> None
Expand source code
def freeze_base_weights(self) -> None:
    self.weight.requires_grad = False
    if self.bias is not None:
        self.bias.requires_grad = False
    if self.lora_rank > 0:
        if self.lora_A is not None:
            self.lora_A.requires_grad = True
        if self.lora_B is not None:
            self.lora_B.requires_grad = True
def reset_parameters(self) ‑> None
Expand source code
def reset_parameters(self) -> None:
    nn.init.kaiming_uniform_(self.weight, a=math.sqrt(5))
    if self.bias is not None:
        fan_in, _ = nn.init._calculate_fan_in_and_fan_out(self.weight)
        bound = 1 / math.sqrt(fan_in) if fan_in > 0 else 0
        nn.init.uniform_(self.bias, -bound, bound)
    if self.lora_rank > 0 and self.lora_A is not None:
        nn.init.kaiming_uniform_(self.lora_A, a=math.sqrt(5))
        self.lora_A.requires_grad = True
    if self.lora_rank > 0 and self.lora_B is not None:
        nn.init.zeros_(self.lora_B)
        self.lora_B.requires_grad = True
class ReGLAAttention (config: Any | None = None,
rank: int = 64,
kernel_size: int = 3,
pretrained_attn: torch.nn.modules.module.Module | None = None,
hidden_size: int | None = None,
num_heads: int | None = None,
is_decoder: bool | None = None,
chunk_size: int = 64,
**kwargs: Any)
Expand source code
@ATTENTION_REGISTRY.register("regla_class")
@ATTENTION_REGISTRY.register("regla_attention_class")
class ReGLAAttention(BaseAttention):
    is_custom_attention: bool = True

    def __init__(
        self,
        config: Any | None = None,
        rank: int = 64,
        kernel_size: int = 3,
        pretrained_attn: nn.Module | None = None,
        hidden_size: int | None = None,
        num_heads: int | None = None,
        is_decoder: bool | None = None,
        chunk_size: int = 64,
        **kwargs: Any,
    ) -> None:
        try:
            super().__init__(config, rank)
        except TypeError:
            super().__init__(config)

        comp_config = getattr(config, "compression_config", None) if config else None
        src = pretrained_attn if pretrained_attn is not None else kwargs.get("source_attn")

        # -------- hidden_size --------
        dim = hidden_size
        if dim is None:
            dim = _cfg_get(config, "hidden_size", kwargs.get("hidden_size", 768))
        self.dim = int(dim)

        # -------- num_heads --------
        n_heads = num_heads
        if n_heads is None:
            n_heads = _cfg_get(config, "num_attention_heads", kwargs.get("num_attention_heads", 12))
        if n_heads is None and src is not None:
            n_heads = getattr(
                src,
                "num_heads",
                getattr(src, "num_attention_heads", getattr(src, "n_head", None)),
            )
        if n_heads is None:
            n_heads = max(1, self.dim // 64)
        self.num_heads = max(1, int(n_heads))

        # -------- head_dim --------
        cfg_hd = _cfg_get(config, "head_dim", None)
        if cfg_hd is not None:
            self.head_dim = int(cfg_hd)
        elif src is not None:
            self.head_dim = None
            for attr in ("q_proj", "query", "q_lin"):
                if hasattr(src, attr):
                    qw = getattr(src, attr)
                    w = getattr(qw, "weight", None)
                    if w is not None:
                        self.head_dim = int(w.shape[0] // self.num_heads)
                        break
            if self.head_dim is None:
                self.head_dim = self.dim // self.num_heads
        else:
            self.head_dim = self.dim // self.num_heads

        if self.dim % self.num_heads != 0:
            self.head_dim = self.dim // self.num_heads

        # -------- num_kv_heads --------
        self.num_kv_heads = int(
            _cfg_get(
                config,
                "num_key_value_heads",
                kwargs.get("num_key_value_heads", self.num_heads),
            )
        )
        self.num_kv_heads = max(1, min(self.num_kv_heads, self.num_heads))
        self.kv_repeat = max(1, self.num_heads // self.num_kv_heads)

        self.all_head_size = self.num_heads * self.head_dim
        self.all_kv_head_size = self.num_kv_heads * self.head_dim

        self.kernel_size = int(kernel_size)
        self.chunk_size = max(1, int(chunk_size))

        self.conv_scale = nn.Parameter(torch.zeros(1))

        # -------- is_decoder --------
        if is_decoder is not None:
            self.is_decoder = bool(is_decoder)
        else:
            mt = str(_cfg_get(config, "model_type", "") or "").lower()
            self.is_decoder = (
                bool(_cfg_get(config, "is_decoder", False))
                or bool(_cfg_get(config, "causal", False))
                or any(
                    mt.startswith(p)
                    for p in (
                        "gpt",
                        "qwen",
                        "llama",
                        "mistral",
                        "gemma",
                        "phi",
                        "opt",
                        "bloom",
                        "falcon",
                    )
                )
                or (src is not None and hasattr(src, "c_attn"))
                or bool(kwargs.get("is_causal", False))
            )
        self.is_causal = self.is_decoder
        self.is_nested_encoder = False

        # -------- LoRA config --------
        self.lora_rank = int(
            _cfg_get(
                config,
                "lora_rank",
                _cfg_get(comp_config, "lora_rank", kwargs.get("lora_rank", 8)),
            )
        )
        self.lora_alpha = float(
            _cfg_get(
                config,
                "lora_alpha",
                _cfg_get(comp_config, "lora_alpha", kwargs.get("lora_alpha", 32.0)),
            )
        )
        self.freeze_base = self.lora_rank > 0

        # -------- device/dtype --------
        target_dtype = kwargs.get("dtype")
        target_device = kwargs.get("device")
        if target_dtype is None and src is not None:
            p = next(src.parameters(), None)
            if p is not None:
                target_dtype = p.dtype
                if target_device is None:
                    target_device = p.device
        if target_dtype is None:
            target_dtype = torch.float32

        # -------- projections --------
        self.q_proj = LoRALinear(
            self.dim,
            self.all_head_size,
            bias=True,
            lora_rank=self.lora_rank,
            lora_alpha=self.lora_alpha,
            freeze_base=self.freeze_base,
            device=target_device,
            dtype=target_dtype,
        )
        self.k_proj = LoRALinear(
            self.dim,
            self.all_kv_head_size,
            bias=True,
            lora_rank=self.lora_rank,
            lora_alpha=self.lora_alpha,
            freeze_base=self.freeze_base,
            device=target_device,
            dtype=target_dtype,
        )
        self.v_proj = LoRALinear(
            self.dim,
            self.all_kv_head_size,
            bias=True,
            lora_rank=self.lora_rank,
            lora_alpha=self.lora_alpha,
            freeze_base=self.freeze_base,
            device=target_device,
            dtype=target_dtype,
        )
        self.gate_proj = LoRALinear(
            self.dim,
            self.all_kv_head_size,
            bias=True,
            lora_rank=self.lora_rank,
            lora_alpha=self.lora_alpha,
            freeze_base=self.freeze_base,
            device=target_device,
            dtype=target_dtype,
        )
        self.out_proj = LoRALinear(
            self.all_head_size,
            self.dim,
            bias=True,
            lora_rank=self.lora_rank,
            lora_alpha=self.lora_alpha,
            freeze_base=self.freeze_base,
            device=target_device,
            dtype=target_dtype,
        )

        # Aliases
        self.query = self.q_proj
        self.key = self.k_proj
        self.value = self.v_proj
        self.q_lin = self.q_proj
        self.k_lin = self.k_proj
        self.v_lin = self.v_proj
        self.out_lin = self.out_proj
        self.dense = self.out_proj

        # Conv1d
        self.conv = nn.Conv1d(
            in_channels=self.dim,
            out_channels=self.dim,
            kernel_size=self.kernel_size,
            groups=self.dim,
            bias=True,
            device=target_device,
            dtype=target_dtype,
        )

        with torch.no_grad():
            nn.init.normal_(self.gate_proj.weight, mean=0.0, std=0.02)
            if self.gate_proj.bias is not None:
                self.gate_proj.bias.zero_()

        if src is not None:
            self.copy_weights(src)

    # ------------------------------------------------------------------
    def copy_weights(self, src: Any) -> None:
        if src is None:
            return

        cls_name = src.__class__.__name__
        has_out_lin = hasattr(src, "out_lin") or hasattr(src, "c_proj") or hasattr(src, "o_proj")
        is_nested = False
        if (
            (
                hasattr(src, "self")
                and hasattr(src.self, "query")
                and hasattr(src, "output")
                and hasattr(src.output, "dense")
            )
            or (
                cls_name
                in [
                    "BertSelfAttention",
                    "RobertaSelfAttention",
                    "XLMRobertaSelfAttention",
                    "ElectraSelfAttention",
                    "DebertaSelfAttention",
                ]
                or (cls_name.endswith("SelfAttention") and "distil" not in cls_name.lower())
            )
            and not has_out_lin
        ):
            is_nested = True
        self.is_nested_encoder = bool(is_nested)

        extracted: dict[str, tuple[torch.Tensor | None, torch.Tensor | None]] = {
            "q": (None, None),
            "k": (None, None),
            "v": (None, None),
            "o": (None, None),
        }

        def _unwrap_linear(layer: Any) -> Any:
            return getattr(layer, "base_layer", layer)

        # GPT-2 fused
        if hasattr(src, "c_attn") and src.c_attn is not None:
            c_attn_mod = _unwrap_linear(src.c_attn)
            c_w = c_attn_mod.weight.data.clone() if hasattr(c_attn_mod, "weight") else None
            if c_w is not None:
                if (
                    c_attn_mod.__class__.__name__ == "Conv1D"
                    or hasattr(c_attn_mod, "nf")
                    or (c_w.ndim == 2 and c_w.shape[0] < c_w.shape[1])
                ):
                    c_w = c_w.t().contiguous()
                split_size = c_w.size(0) // 3
                bias_mod = getattr(c_attn_mod, "bias", None)
                c_b = bias_mod.data.clone() if bias_mod is not None else None
                extracted["q"] = (
                    c_w[:split_size, :],
                    c_b[:split_size] if c_b is not None else None,
                )
                extracted["k"] = (
                    c_w[split_size : 2 * split_size, :],
                    c_b[split_size : 2 * split_size] if c_b is not None else None,
                )
                extracted["v"] = (
                    c_w[2 * split_size :, :],
                    c_b[2 * split_size :] if c_b is not None else None,
                )

            if hasattr(src, "c_proj") and src.c_proj is not None:
                c_proj_mod = _unwrap_linear(src.c_proj)
                o_w = c_proj_mod.weight.data.clone() if hasattr(c_proj_mod, "weight") else None
                if o_w is not None:
                    if (
                        c_proj_mod.__class__.__name__ == "Conv1D"
                        or hasattr(c_proj_mod, "nf")
                        or (o_w.ndim == 2 and o_w.shape[0] < o_w.shape[1])
                    ):
                        o_w = o_w.t().contiguous()
                    bias_o = getattr(c_proj_mod, "bias", None)
                    extracted["o"] = (
                        o_w,
                        bias_o.data.clone() if bias_o is not None else None,
                    )

        # RoBERTa nested (outer container)
        elif hasattr(src, "self") and hasattr(src.self, "query"):
            s = src.self
            for proj_key, sub_name in (("q", "query"), ("k", "key"), ("v", "value")):
                mod = getattr(s, sub_name, None)
                if mod is not None and hasattr(mod, "weight"):
                    extracted[proj_key] = (
                        mod.weight.data.clone(),
                        mod.bias.data.clone() if mod.bias is not None else None,
                    )
            if hasattr(src, "output") and hasattr(src.output, "dense"):
                out_mod = src.output.dense
                extracted["o"] = (
                    out_mod.weight.data.clone(),
                    out_mod.bias.data.clone() if out_mod.bias is not None else None,
                )

        # Flat modules
        else:
            proj_candidates = {
                "q": ["q_lin", "q_proj", "query"],
                "k": ["k_lin", "k_proj", "key"],
                "v": ["v_lin", "v_proj", "value"],
                "o": ["out_lin", "out_proj", "dense", "o_proj"],
            }
            for proj_key, names in proj_candidates.items():
                for name in names:
                    if hasattr(src, name):
                        mod = getattr(src, name)
                        if mod is not None and hasattr(mod, "weight"):
                            extracted[proj_key] = (
                                mod.weight.data.clone(),
                                mod.bias.data.clone() if mod.bias is not None else None,
                            )
                            break

        missing = [
            k
            for k, (w, _) in extracted.items()
            if w is None and (k != "o" or not self.is_nested_encoder)
        ]
        if missing:
            try:
                from neuralops.core.adapters import UniversalAdapter

                adapter = UniversalAdapter()
                for k in missing:
                    w, b = adapter.get_weight_bias(src, k)
                    if w is not None:
                        extracted[k] = (
                            w.data.clone(),
                            b.data.clone() if b is not None else None,
                        )
            except Exception as e:
                logger.debug("UniversalAdapter failed: %s", e)

        missing_after = [
            k
            for k, (w, _) in extracted.items()
            if w is None and (k != "o" or not self.is_nested_encoder)
        ]
        if missing_after:
            raise RuntimeError(
                f"ReGLAAttention.copy_weights: missing {missing_after} from {cls_name}."
            )

        with torch.no_grad():
            for proj_key, target_mod in (
                ("q", self.q_proj),
                ("k", self.k_proj),
                ("v", self.v_proj),
                ("o", self.out_proj),
            ):
                w, b = extracted[proj_key]
                if w is None:
                    if proj_key == "o" and self.is_nested_encoder:
                        nn.init.eye_(target_mod.weight)
                        if target_mod.bias is not None:
                            target_mod.bias.zero_()
                    continue

                if w.ndim != 2:
                    w = w.reshape(w.size(0), -1)

                if (
                    w.shape != target_mod.weight.shape
                    and target_mod.weight.shape == w.t().contiguous().shape
                ):
                    w = w.t().contiguous()

                out_d = min(target_mod.weight.size(0), w.size(0))
                in_d = min(target_mod.weight.size(1), w.size(1))
                target_mod.weight.data[:out_d, :in_d].copy_(
                    w[:out_d, :in_d].to(
                        device=target_mod.weight.device, dtype=target_mod.weight.dtype
                    )
                )

                if b is not None and target_mod.bias is not None:
                    min_b = min(target_mod.bias.numel(), b.numel())
                    target_mod.bias.data[:min_b].copy_(
                        b[:min_b].to(device=target_mod.bias.device, dtype=target_mod.bias.dtype)
                    )
                elif target_mod.bias is not None:
                    target_mod.bias.data.zero_()

                w_norm = float(torch.norm(target_mod.weight.data).item())
                if w_norm < 1e-4:
                    logger.warning(
                        "ReGLAAttention: weight for '%s' has near-zero norm (%.2e)",
                        proj_key,
                        w_norm,
                    )

                if self.freeze_base:
                    target_mod.freeze_base_weights()

    # ------------------------------------------------------------------
    def forward(
        self,
        hidden_states: torch.Tensor,
        attention_mask: torch.Tensor | None = None,
        head_mask: torch.Tensor | None = None,
        encoder_hidden_states: torch.Tensor | None = None,
        position_embeddings: tuple[torch.Tensor, torch.Tensor] | None = None,
        past_key_value: Any | None = None,
        output_attentions: bool | None = False,
        layer_idx: int = 0,
        *args: Any,
        **kwargs: Any,
    ):
        if encoder_hidden_states is not None:
            raise NotImplementedError("ReGLAAttention does not support cross-attention")

        x = hidden_states
        B, L, D = x.shape
        device = x.device
        dtype = x.dtype

        q = (
            self.q_proj(x)
            .view(B, L, self.num_heads, self.head_dim)
            .permute(0, 2, 1, 3)
            .contiguous()
        )
        k = (
            self.k_proj(x)
            .view(B, L, self.num_kv_heads, self.head_dim)
            .permute(0, 2, 1, 3)
            .contiguous()
        )
        v = (
            self.v_proj(x)
            .view(B, L, self.num_kv_heads, self.head_dim)
            .permute(0, 2, 1, 3)
            .contiguous()
        )
        g = (
            self.gate_proj(x)
            .view(B, L, self.num_kv_heads, self.head_dim)
            .permute(0, 2, 1, 3)
            .contiguous()
        )

        # RoPE with past_len offset
        if position_embeddings is None:
            position_embeddings = kwargs.get("position_embeddings")
        if position_embeddings is not None:
            cos, sin = position_embeddings
            past_len = 0
            if past_key_value is not None:
                if isinstance(past_key_value, (tuple, list)) and len(past_key_value) >= 1:
                    past_len = past_key_value[0].shape[-2]
                elif hasattr(past_key_value, "key_cache") and past_key_value.key_cache:
                    past_len = past_key_value.key_cache[0].shape[-2]
            cos = cos[..., past_len : past_len + L, :]
            sin = sin[..., past_len : past_len + L, :]
            q, k = apply_rotary_pos_emb(q, k, cos, sin)

        # GQA expansion
        if self.num_heads != self.num_kv_heads:
            k = repeat_kv(k, self.kv_repeat)
            v = repeat_kv(v, self.kv_repeat)
            g = repeat_kv(g, self.kv_repeat)

        # Non-negative kernel activation & gating
        q_act = F.elu(q.float()) + 1.0
        k_act = F.elu(k.float()) + 1.0
        g_sig = torch.sigmoid(g.float())

        # Valid mask
        if attention_mask is not None:
            if attention_mask.dim() == 2:
                valid_mask = (
                    (attention_mask > 0)
                    if not attention_mask.dtype.is_floating_point
                    else (attention_mask > -1e4)
                )
            elif attention_mask.dim() == 4:
                if attention_mask.dtype.is_floating_point:
                    valid_mask = (attention_mask > -1e4).any(dim=-2).squeeze(1)
                else:
                    valid_mask = attention_mask.bool().any(dim=-2).squeeze(1)
            else:
                valid_mask = torch.ones(B, L, device=device, dtype=torch.bool)
        else:
            valid_mask = torch.ones(B, L, device=device, dtype=torch.bool)

        mask_4d = valid_mask[:, None, :, None].to(q_act.dtype)
        k_gated = k_act * g_sig * mask_4d
        v_gated = v.float() * g_sig * mask_4d

        is_causal = self.is_decoder or kwargs.get("is_causal", False)

        if is_causal:
            chunk = self.chunk_size
            S = torch.zeros(
                B,
                self.num_heads,
                self.head_dim,
                self.head_dim,
                device=device,
                dtype=q_act.dtype,
            )
            Z = torch.zeros(B, self.num_heads, self.head_dim, device=device, dtype=q_act.dtype)
            out_list = []

            for start in range(0, L, chunk):
                end = min(start + chunk, L)
                q_c = q_act[:, :, start:end]
                k_c = k_gated[:, :, start:end]
                v_c = v_gated[:, :, start:end]

                intra_kv = torch.cumsum(k_c.unsqueeze(-1) * v_c.unsqueeze(-2), dim=2)
                num_intra = (q_c.unsqueeze(-2) @ intra_kv).squeeze(-2)
                num_inter = (q_c.unsqueeze(-2) @ S.unsqueeze(2)).squeeze(-2)
                num = num_intra + num_inter

                z_intra = torch.cumsum(k_c, dim=2)
                den = (q_c * (z_intra + Z.unsqueeze(2))).sum(-1, keepdim=True).clamp(min=1e-4)
                out_list.append(num / den)

                S = S + (k_c.unsqueeze(-1) * v_c.unsqueeze(-2)).sum(dim=2)
                Z = Z + k_c.sum(dim=2)

            out = torch.cat(out_list, dim=2)
        else:
            kv = torch.matmul(k_gated.transpose(-2, -1).contiguous(), v_gated)
            z = k_gated.sum(dim=2, keepdim=True)
            num = torch.matmul(q_act, kv)
            den = (q_act * z).sum(-1, keepdim=True).clamp(min=1e-4)
            out = num / den

        out = out * mask_4d

        if head_mask is not None:
            if head_mask.dim() == 1:
                hm = head_mask.view(1, -1, 1, 1)
            elif head_mask.dim() == 2:
                hm = head_mask.unsqueeze(-1).unsqueeze(-1)
            elif head_mask.dim() == 3:
                hm = head_mask[:, :, :1].unsqueeze(-1)
            else:
                hm = head_mask
            out = out * hm.to(out.dtype)

        out = out.permute(0, 2, 1, 3).contiguous().view(B, L, self.all_head_size).to(dtype)

        # Depthwise 1D conv branch
        x_in = (x * valid_mask.unsqueeze(-1).to(dtype)).permute(0, 2, 1)
        conv_w = self.conv.weight.to(dtype)
        conv_b = self.conv.bias.to(dtype) if self.conv.bias is not None else None
        if is_causal:
            x_pad = F.pad(x_in, (self.kernel_size - 1, 0))
            loc = F.conv1d(
                x_pad,
                conv_w,
                conv_b,
                stride=self.conv.stride,
                padding=self.conv.padding,
                dilation=self.conv.dilation,
                groups=self.conv.groups,
            ).permute(0, 2, 1)
        else:
            p = self.kernel_size // 2
            x_pad = F.pad(x_in, (p, p))
            loc = F.conv1d(
                x_pad,
                conv_w,
                conv_b,
                stride=self.conv.stride,
                padding=self.conv.padding,
                dilation=self.conv.dilation,
                groups=self.conv.groups,
            ).permute(0, 2, 1)

        if loc.shape[-1] != self.dim:
            raise RuntimeError(
                f"ReGLAAttention: conv output dim {loc.shape[-1]} != hidden dim {self.dim}"
            )

        fused = (out.to(dtype) + self.conv_scale.to(dtype) * loc.to(dtype)).to(dtype)
        fused = fused * valid_mask.unsqueeze(-1).to(dtype)

        if self.is_nested_encoder:
            output = fused
        else:
            output = self.out_proj(fused)

        if output.shape[-1] != D:
            raise RuntimeError(f"ReGLAAttention: output dim {output.shape[-1]} != input {D}")

        return output.to(dtype), None

Every custom attention module must inherit from this.

Initialize internal Module state, shared by both nn.Module and ScriptModule.

Ancestors

Class variables

var is_custom_attention : bool

The type of the None singleton.

Inherited members