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Aluode/PerceptionLabPortable

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1# Copyright 2020 The HuggingFace Team. All rights reserved.2#3# Licensed under the Apache License, Version 2.0 (the "License");4# you may not use this file except in compliance with the License.5# You may obtain a copy of the License at6#7#     http://www.apache.org/licenses/LICENSE-2.08#9# Unless required by applicable law or agreed to in writing, software10# distributed under the License is distributed on an "AS IS" BASIS,11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.12# See the License for the specific language governing permissions and13# limitations under the License.14 15import functools16import math17from collections import OrderedDict18 19import torch20from torch import Tensor, nn21 22from .integrations.hub_kernels import use_kernel_forward_from_hub23from .utils import logging24from .utils.import_utils import is_torchdynamo_compiling25 26 27logger = logging.get_logger(__name__)28 29 30@use_kernel_forward_from_hub("GeluTanh")31class GELUTanh(nn.Module):32    """33    A fast C implementation of the tanh approximation of the GeLU activation function. See34    https://huggingface.co/papers/1606.08415.35 36    This implementation is equivalent to NewGELU and FastGELU but much faster. However, it is not an exact numerical37    match due to rounding errors.38    """39 40    def __init__(self, use_gelu_tanh_python: bool = False):41        super().__init__()42        if use_gelu_tanh_python:43            self.act = self._gelu_tanh_python44        else:45            self.act = functools.partial(nn.functional.gelu, approximate="tanh")46 47    def _gelu_tanh_python(self, input: Tensor) -> Tensor:48        return input * 0.5 * (1.0 + torch.tanh(math.sqrt(2.0 / math.pi) * (input + 0.044715 * torch.pow(input, 3.0))))49 50    def forward(self, input: Tensor) -> Tensor:51        return self.act(input)52 53 54@use_kernel_forward_from_hub("NewGELU")55class NewGELUActivation(nn.Module):56    """57    Implementation of the GELU activation function currently in Google BERT repo (identical to OpenAI GPT). Also see58    the Gaussian Error Linear Units paper: https://huggingface.co/papers/1606.0841559    """60 61    def forward(self, input: Tensor) -> Tensor:62        return 0.5 * input * (1.0 + torch.tanh(math.sqrt(2.0 / math.pi) * (input + 0.044715 * torch.pow(input, 3.0))))63 64 65@use_kernel_forward_from_hub("GeLU")66class GELUActivation(nn.Module):67    """68    Original Implementation of the GELU activation function in Google BERT repo when initially created. For69    information: OpenAI GPT's GELU is slightly different (and gives slightly different results): 0.5 * x * (1 +70    torch.tanh(math.sqrt(2 / math.pi) * (x + 0.044715 * torch.pow(x, 3)))) This is now written in C in nn.functional71    Also see the Gaussian Error Linear Units paper: https://huggingface.co/papers/1606.0841572    """73 74    def __init__(self, use_gelu_python: bool = False):75        super().__init__()76        if use_gelu_python:77            self.act = self._gelu_python78        else:79            self.act = nn.functional.gelu80 81    def _gelu_python(self, input: Tensor) -> Tensor:82        return input * 0.5 * (1.0 + torch.erf(input / math.sqrt(2.0)))83 84    def forward(self, input: Tensor) -> Tensor:85        return self.act(input)86 87 88@use_kernel_forward_from_hub("SiLU")89class SiLUActivation(nn.Module):90    """91    See Gaussian Error Linear Units (Hendrycks et al., https://arxiv.org/abs/1606.08415) where the SiLU (Sigmoid Linear92    Unit) was originally introduced and coined, and see Sigmoid-Weighted Linear Units for Neural Network Function93    Approximation in Reinforcement Learning (Elfwing et al., https://arxiv.org/abs/1702.03118) and Swish: a Self-Gated94    Activation Function (Ramachandran et al., https://arxiv.org/abs/1710.05941v1) where the SiLU was experimented with95    later.96    """97 98    def forward(self, input: Tensor) -> Tensor:99        return nn.functional.silu(input)100 101 102@use_kernel_forward_from_hub("FastGELU")103class FastGELUActivation(nn.Module):104    """105    Applies GELU approximation that is slower than QuickGELU but more accurate. See: https://github.com/hendrycks/GELUs106    """107 108    def forward(self, input: Tensor) -> Tensor:109        return 0.5 * input * (1.0 + torch.tanh(input * 0.7978845608 * (1.0 + 0.044715 * input * input)))110 111 112@use_kernel_forward_from_hub("QuickGELU")113class QuickGELUActivation(nn.Module):114    """115    Applies GELU approximation that is fast but somewhat inaccurate. See: https://github.com/hendrycks/GELUs116    """117 118    def forward(self, input: Tensor) -> Tensor:119        return input * torch.sigmoid(1.702 * input)120 121 122class ClippedGELUActivation(nn.Module):123    """124    Clip the range of possible GeLU outputs between [min, max]. This is especially useful for quantization purpose, as125    it allows mapping negatives values in the GeLU spectrum. For more information on this trick, please refer to126    https://huggingface.co/papers/2004.09602.127 128    Gaussian Error Linear Unit. Original Implementation of the gelu activation function in Google Bert repo when129    initially created.130 131    For information: OpenAI GPT's gelu is slightly different (and gives slightly different results): 0.5 * x * (1 +132    torch.tanh(math.sqrt(2 / math.pi) * (x + 0.044715 * torch.pow(x, 3)))). See https://huggingface.co/papers/1606.08415133    """134 135    def __init__(self, min: float, max: float):136        if min > max:137            raise ValueError(f"min should be < max (got min: {min}, max: {max})")138 139        super().__init__()140        self.min = min141        self.max = max142 143    def forward(self, x: Tensor) -> Tensor:144        return torch.clip(gelu(x), self.min, self.max)145 146 147class AccurateGELUActivation(nn.Module):148    """149    Applies GELU approximation that is faster than default and more accurate than QuickGELU. See:150    https://github.com/hendrycks/GELUs151 152    Implemented along with MEGA (Moving Average Equipped Gated Attention)153    """154 155    def __init__(self):156        super().__init__()157        self.precomputed_constant = math.sqrt(2 / math.pi)158 159    def forward(self, input: Tensor) -> Tensor:160        return 0.5 * input * (1 + torch.tanh(self.precomputed_constant * (input + 0.044715 * torch.pow(input, 3))))161 162 163class MishActivation(nn.Module):164    """165    See Mish: A Self-Regularized Non-Monotonic Activation Function (Misra., https://huggingface.co/papers/1908.08681). Also166    visit the official repository for the paper: https://github.com/digantamisra98/Mish167    """168 169    def __init__(self):170        super().__init__()171        self.act = nn.functional.mish172 173    def _mish_python(self, input: Tensor) -> Tensor:174        return input * torch.tanh(nn.functional.softplus(input))175 176    def forward(self, input: Tensor) -> Tensor:177        return self.act(input)178 179 180class LinearActivation(nn.Module):181    """182    Applies the linear activation function, i.e. forwarding input directly to output.183    """184 185    def forward(self, input: Tensor) -> Tensor:186        return input187 188 189class LaplaceActivation(nn.Module):190    """191    Applies elementwise activation based on Laplace function, introduced in MEGA as an attention activation. See192    https://huggingface.co/papers/2209.10655193 194    Inspired by squared relu, but with bounded range and gradient for better stability195    """196 197    def forward(self, input, mu=0.707107, sigma=0.282095):198        input = (input - mu).div(sigma * math.sqrt(2.0))199        return 0.5 * (1.0 + torch.erf(input))200 201 202class ReLUSquaredActivation(nn.Module):203    """204    Applies the relu^2 activation introduced in https://huggingface.co/papers/2109.08668v2205    """206 207    def forward(self, input):208        relu_applied = nn.functional.relu(input)209        squared = torch.square(relu_applied)210        return squared211 212 213class ClassInstantier(OrderedDict):214    def __getitem__(self, key):215        content = super().__getitem__(key)216        cls, kwargs = content if isinstance(content, tuple) else (content, {})217        return cls(**kwargs)218 219 220class XIELUActivation(nn.Module):221    """222    Applies the xIELU activation function introduced in https://arxiv.org/abs/2411.13010223 224    If the user has installed the nickjbrowning/XIELU wheel, we import xIELU CUDA225    Otherwise, we emit a single warning and use xIELU Python226    """227 228    def __init__(229        self,230        alpha_p_init=0.8,231        alpha_n_init=0.8,232        beta=0.5,233        eps=-1e-6,234        dtype=torch.bfloat16,235        with_vector_loads=False,236    ):237        super().__init__()238        self.alpha_p = nn.Parameter(torch.log(torch.expm1(torch.tensor(alpha_p_init, dtype=dtype))).unsqueeze(0))239        self.alpha_n = nn.Parameter(240            torch.log(torch.expm1(torch.tensor(alpha_n_init - beta, dtype=dtype))).unsqueeze(0)241        )242        self.register_buffer("beta", torch.tensor(beta, dtype=dtype))243        self.register_buffer("eps", torch.tensor(eps, dtype=dtype))244        self.with_vector_loads = with_vector_loads245        # Temporary until xIELU CUDA fully implemented246        self._beta_scalar = float(self.beta.detach().cpu().float().item())247        self._eps_scalar = float(self.eps.detach().cpu().float().item())248 249        self._xielu_cuda_obj = None250        try:251            import xielu.ops  # noqa: F401252 253            self._xielu_cuda_obj = torch.classes.xielu.XIELU()254            msg = "Using experimental xIELU CUDA."255            try:256                from torch._dynamo import allow_in_graph257 258                self._xielu_cuda_fn = allow_in_graph(self._xielu_cuda)259                msg += " Enabled torch._dynamo for xIELU CUDA."260            except Exception as err:261                msg += f" Could not enable torch._dynamo for xIELU ({err}) - this may result in slower performance."262                self._xielu_cuda_fn = self._xielu_cuda263            logger.warning_once(msg)264        except Exception as err:265            logger.warning_once(266                "CUDA-fused xIELU not available (%s) – falling back to a Python version.\n"267                "For CUDA xIELU (experimental), `pip install git+https://github.com/nickjbrowning/XIELU`",268                str(err),269            )270 271    def _xielu_python(self, x: Tensor) -> Tensor:272        alpha_p = nn.functional.softplus(self.alpha_p)273        alpha_n = self.beta + nn.functional.softplus(self.alpha_n)274        return torch.where(275            x > 0,276            alpha_p * x * x + self.beta * x,277            (torch.expm1(torch.min(x, self.eps)) - x) * alpha_n + self.beta * x,278        )279 280    def _xielu_cuda(self, x: Tensor) -> Tensor:281        """Firewall function to prevent torch.compile from seeing .item() calls"""282        original_shape = x.shape283        # CUDA kernel expects 3D tensors, reshape if needed284        while x.dim() < 3:285            x = x.unsqueeze(0)286        if x.dim() > 3:287            x = x.view(-1, 1, x.size(-1))288        if original_shape != x.shape:289            logger.warning_once(290                "Warning: xIELU input tensor expects 3 dimensions but got (shape: %s). Reshaping to (shape: %s).",291                original_shape,292                x.shape,293            )294        result = self._xielu_cuda_obj.forward(295            x,296            self.alpha_p.to(x.dtype),297            self.alpha_n.to(x.dtype),298            # Temporary until xIELU CUDA fully implemented -> self.{beta,eps}.item()299            self._beta_scalar,300            self._eps_scalar,301            self.with_vector_loads,302        )303        return result.view(original_shape)304 305    def forward(self, input: Tensor) -> Tensor:306        if self._xielu_cuda_obj is not None and input.is_cuda:307            if not is_torchdynamo_compiling():308                return self._xielu_cuda_fn(input)309            else:310                logger.warning_once("torch._dynamo is compiling, using Python version of xIELU.")311        return self._xielu_python(input)312 313 314ACT2CLS = {315    "gelu": GELUActivation,316    "gelu_10": (ClippedGELUActivation, {"min": -10, "max": 10}),317    "gelu_fast": FastGELUActivation,318    "gelu_new": NewGELUActivation,319    "gelu_python": (GELUActivation, {"use_gelu_python": True}),320    "gelu_pytorch_tanh": GELUTanh,321    "gelu_python_tanh": (GELUTanh, {"use_gelu_tanh_python": True}),322    "gelu_accurate": AccurateGELUActivation,323    "laplace": LaplaceActivation,324    "leaky_relu": nn.LeakyReLU,325    "linear": LinearActivation,326    "mish": MishActivation,327    "quick_gelu": QuickGELUActivation,328    "relu": nn.ReLU,329    "relu2": ReLUSquaredActivation,330    "relu6": nn.ReLU6,331    "sigmoid": nn.Sigmoid,332    "silu": SiLUActivation,333    "swish": nn.SiLU,334    "tanh": nn.Tanh,335    "prelu": nn.PReLU,336    "xielu": XIELUActivation,337}338ACT2FN = ClassInstantier(ACT2CLS)339 340 341def get_activation(activation_string):342    if activation_string in ACT2FN:343        return ACT2FN[activation_string]344    else:345        raise KeyError(f"function {activation_string} not found in ACT2FN mapping {list(ACT2FN.keys())}")346 347 348# For backwards compatibility with: from activations import gelu_python349gelu_python = get_activation("gelu_python")350gelu_new = get_activation("gelu_new")351gelu = get_activation("gelu")352gelu_fast = get_activation("gelu_fast")353quick_gelu = get_activation("quick_gelu")354silu = get_activation("silu")355mish = get_activation("mish")356linear_act = get_activation("linear")357 
Aluode/PerceptionLabPortable · CoolFace