File size: 5,886 Bytes
786f6a6 |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 |
""" Activations (memory-efficient w/ custom autograd)
A collection of activations fn and modules with a common interface so that they can
easily be swapped. All have an `inplace` arg even if not used.
These activations are not compatible with jit scripting or ONNX export of the model, please use either
the JIT or basic versions of the activations.
Hacked together by / Copyright 2020 Ross Wightman
"""
import torch
from torch import nn as nn
from torch.nn import functional as F
@torch.jit.script
def swish_jit_fwd(x):
return x.mul(torch.sigmoid(x))
@torch.jit.script
def swish_jit_bwd(x, grad_output):
x_sigmoid = torch.sigmoid(x)
return grad_output * (x_sigmoid * (1 + x * (1 - x_sigmoid)))
class SwishJitAutoFn(torch.autograd.Function):
""" torch.jit.script optimised Swish w/ memory-efficient checkpoint
Inspired by conversation btw Jeremy Howard & Adam Pazske
https://twitter.com/jeremyphoward/status/1188251041835315200
"""
@staticmethod
def symbolic(g, x):
return g.op("Mul", x, g.op("Sigmoid", x))
@staticmethod
def forward(ctx, x):
ctx.save_for_backward(x)
return swish_jit_fwd(x)
@staticmethod
def backward(ctx, grad_output):
x = ctx.saved_tensors[0]
return swish_jit_bwd(x, grad_output)
def swish_me(x, inplace=False):
return SwishJitAutoFn.apply(x)
class SwishMe(nn.Module):
def __init__(self, inplace: bool = False):
super(SwishMe, self).__init__()
def forward(self, x):
return SwishJitAutoFn.apply(x)
@torch.jit.script
def mish_jit_fwd(x):
return x.mul(torch.tanh(F.softplus(x)))
@torch.jit.script
def mish_jit_bwd(x, grad_output):
x_sigmoid = torch.sigmoid(x)
x_tanh_sp = F.softplus(x).tanh()
return grad_output.mul(x_tanh_sp + x * x_sigmoid * (1 - x_tanh_sp * x_tanh_sp))
class MishJitAutoFn(torch.autograd.Function):
""" Mish: A Self Regularized Non-Monotonic Neural Activation Function - https://arxiv.org/abs/1908.08681
A memory efficient, jit scripted variant of Mish
"""
@staticmethod
def forward(ctx, x):
ctx.save_for_backward(x)
return mish_jit_fwd(x)
@staticmethod
def backward(ctx, grad_output):
x = ctx.saved_tensors[0]
return mish_jit_bwd(x, grad_output)
def mish_me(x, inplace=False):
return MishJitAutoFn.apply(x)
class MishMe(nn.Module):
def __init__(self, inplace: bool = False):
super(MishMe, self).__init__()
def forward(self, x):
return MishJitAutoFn.apply(x)
@torch.jit.script
def hard_sigmoid_jit_fwd(x, inplace: bool = False):
return (x + 3).clamp(min=0, max=6).div(6.)
@torch.jit.script
def hard_sigmoid_jit_bwd(x, grad_output):
m = torch.ones_like(x) * ((x >= -3.) & (x <= 3.)) / 6.
return grad_output * m
class HardSigmoidJitAutoFn(torch.autograd.Function):
@staticmethod
def forward(ctx, x):
ctx.save_for_backward(x)
return hard_sigmoid_jit_fwd(x)
@staticmethod
def backward(ctx, grad_output):
x = ctx.saved_tensors[0]
return hard_sigmoid_jit_bwd(x, grad_output)
def hard_sigmoid_me(x, inplace: bool = False):
return HardSigmoidJitAutoFn.apply(x)
class HardSigmoidMe(nn.Module):
def __init__(self, inplace: bool = False):
super(HardSigmoidMe, self).__init__()
def forward(self, x):
return HardSigmoidJitAutoFn.apply(x)
@torch.jit.script
def hard_swish_jit_fwd(x):
return x * (x + 3).clamp(min=0, max=6).div(6.)
@torch.jit.script
def hard_swish_jit_bwd(x, grad_output):
m = torch.ones_like(x) * (x >= 3.)
m = torch.where((x >= -3.) & (x <= 3.), x / 3. + .5, m)
return grad_output * m
class HardSwishJitAutoFn(torch.autograd.Function):
"""A memory efficient, jit-scripted HardSwish activation"""
@staticmethod
def forward(ctx, x):
ctx.save_for_backward(x)
return hard_swish_jit_fwd(x)
@staticmethod
def backward(ctx, grad_output):
x = ctx.saved_tensors[0]
return hard_swish_jit_bwd(x, grad_output)
@staticmethod
def symbolic(g, self):
input = g.op("Add", self, g.op('Constant', value_t=torch.tensor(3, dtype=torch.float)))
hardtanh_ = g.op("Clip", input, g.op('Constant', value_t=torch.tensor(0, dtype=torch.float)), g.op('Constant', value_t=torch.tensor(6, dtype=torch.float)))
hardtanh_ = g.op("Div", hardtanh_, g.op('Constant', value_t=torch.tensor(6, dtype=torch.float)))
return g.op("Mul", self, hardtanh_)
def hard_swish_me(x, inplace=False):
return HardSwishJitAutoFn.apply(x)
class HardSwishMe(nn.Module):
def __init__(self, inplace: bool = False):
super(HardSwishMe, self).__init__()
def forward(self, x):
return HardSwishJitAutoFn.apply(x)
@torch.jit.script
def hard_mish_jit_fwd(x):
return 0.5 * x * (x + 2).clamp(min=0, max=2)
@torch.jit.script
def hard_mish_jit_bwd(x, grad_output):
m = torch.ones_like(x) * (x >= -2.)
m = torch.where((x >= -2.) & (x <= 0.), x + 1., m)
return grad_output * m
class HardMishJitAutoFn(torch.autograd.Function):
""" A memory efficient, jit scripted variant of Hard Mish
Experimental, based on notes by Mish author Diganta Misra at
https://github.com/digantamisra98/H-Mish/blob/0da20d4bc58e696b6803f2523c58d3c8a82782d0/README.md
"""
@staticmethod
def forward(ctx, x):
ctx.save_for_backward(x)
return hard_mish_jit_fwd(x)
@staticmethod
def backward(ctx, grad_output):
x = ctx.saved_tensors[0]
return hard_mish_jit_bwd(x, grad_output)
def hard_mish_me(x, inplace: bool = False):
return HardMishJitAutoFn.apply(x)
class HardMishMe(nn.Module):
def __init__(self, inplace: bool = False):
super(HardMishMe, self).__init__()
def forward(self, x):
return HardMishJitAutoFn.apply(x)
|