1 /*
2 * Copyright (c) 2020-2022 Arm Limited.
3 *
4 * SPDX-License-Identifier: MIT
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to
8 * deal in the Software without restriction, including without limitation the
9 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
10 * sell copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in all
14 * copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
19 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
22 * SOFTWARE.
23 */
24 #include "arm_compute/core/Helpers.h"
25 #include "arm_compute/core/Window.h"
26 #include "src/core/NEON/wrapper/wrapper.h"
27 namespace arm_compute
28 {
29 namespace cpu
30 {
31 /** Constant parameters needed by the activation implementation.
32 * These parameters differ for each floating type
33 *
34 * @note This are passed as a struct as C++ does not allow float as a template parameter until C++20
35 **/
36 struct ActFpImplParams
37 {
38 float delta; /**< Minimum delta needed to avoid NaN on corner-cases of elementary functions */
39 int step_x; /**< Window step at the x dimension */
40 };
41
42 #ifndef __aarch64__
mask_float_vector(const float32x4_t & in,const uint32x4_t & mask)43 inline float32x4_t mask_float_vector(const float32x4_t &in, const uint32x4_t &mask)
44 {
45 auto int_in = vreinterpretq_u32_f32(in);
46 return vreinterpretq_f32_u32(wrapper::vand(int_in, mask));
47 }
48 #if defined(__ARM_FEATURE_FP16_VECTOR_ARITHMETIC) && defined(ENABLE_FP16_KERNELS)
mask_float_vector(const float16x8_t & in,const uint16x8_t & mask)49 inline float16x8_t mask_float_vector(const float16x8_t &in, const uint16x8_t &mask)
50 {
51 auto int_in = vreinterpretq_u16_f16(in);
52 return vreinterpretq_f16_u16(wrapper::vand(int_in, mask));
53 }
54 #endif //defined(__ARM_FEATURE_FP16_VECTOR_ARITHMETIC) && defined(ENABLE_FP16_KERNELS)
55 #endif /* __aarch64__ */
56
57 template <typename T, const ActFpImplParams &P>
fp_neon_activation_impl(const ITensor * src,ITensor * dst,const ActivationLayerInfo & act_info,const Window & window)58 void fp_neon_activation_impl(const ITensor *src, ITensor *dst, const ActivationLayerInfo &act_info, const Window &window)
59 {
60 /** SIMD vector tag type. */
61 using ExactTagType = typename arm_compute::wrapper::traits::neon_bitvector_tag_t<T, wrapper::traits::BitWidth::W128>;
62 constexpr int window_step_x = P.step_x;
63 const auto window_start_x = static_cast<int>(window.x().start());
64 const auto window_end_x = static_cast<int>(window.x().end());
65 const ActivationLayerInfo::ActivationFunction act = act_info.activation();
66 Window win_collapsed = window.collapse_if_possible(window, Window::DimZ);
67 win_collapsed.set(Window::DimX, Window::Dimension(0, 1, 1));
68 Iterator input(src, win_collapsed);
69 Iterator output(dst, win_collapsed);
70 // In case of non-aarch64, a small delta value is added to the input
71 // to prevent NAN values caused by zeros in inputs to SQRT.
72 // In case of aarh64, we call vsqrt directly, so we don't use delta.
73 #ifndef __aarch64__
74 const auto delta = wrapper::vdup_n(static_cast<T>(P.delta), ExactTagType {});
75 #else /* #ifndef __aarch64__ */
76 const auto const_inv_2 = wrapper::vdup_n(static_cast<T>(0.5f), ExactTagType {});
77 const auto const_inv_sqrt_2 = wrapper::vdup_n(static_cast<T>(0.70710678118f), ExactTagType{});
78 #endif /* __aarch64__ */
79 const auto const_1 = wrapper::vdup_n(static_cast<T>(1.f), ExactTagType {});
80 const auto const_0 = wrapper::vdup_n(static_cast<T>(0.f), ExactTagType{});
81 const auto const_6 = wrapper::vdup_n(static_cast<T>(6.f), ExactTagType{});
82 const auto const_3 = wrapper::vdup_n(static_cast<T>(3.f), ExactTagType{});
83 const auto const_inv_6 = wrapper::vdup_n(static_cast<T>(0.166666667f), ExactTagType{});
84 constexpr float soft_relu_thresh = 12.f;
85 const auto vsoft_relu_thresh = wrapper::vdup_n(static_cast<T>(soft_relu_thresh), ExactTagType{});
86 const auto va = wrapper::vdup_n(static_cast<T>(act_info.a()), ExactTagType{});
87 const auto vb = wrapper::vdup_n(static_cast<T>(act_info.b()), ExactTagType{});
88 const auto a = static_cast<T>(act_info.a());
89 const auto b = static_cast<T>(act_info.b());
90 execute_window_loop(win_collapsed, [&](const Coordinates &)
91 {
92 const auto input_ptr = reinterpret_cast<const T *>(input.ptr());
93 const auto output_ptr = reinterpret_cast<T *>(output.ptr());
94 wrapper::traits::neon_bitvector_t<T, wrapper::traits::BitWidth::W128> tmp;
95 // Compute S elements per iteration
96 int x = window_start_x;
97 for(; x <= (window_end_x - window_step_x); x += window_step_x)
98 {
99 const auto vin = wrapper::vloadq(input_ptr + x);
100 switch(act)
101 {
102 case ActivationLayerInfo::ActivationFunction::ABS:
103 tmp = wrapper::vabs(vin);
104 break;
105 case ActivationLayerInfo::ActivationFunction::LINEAR:
106 tmp = wrapper::vmla(vb, va, vin);
107 break;
108 case ActivationLayerInfo::ActivationFunction::LOGISTIC:
109 tmp = wrapper::vinv(wrapper::vadd(const_1, wrapper::vexpq(wrapper::vneg(vin))));
110 break;
111 case ActivationLayerInfo::ActivationFunction::RELU:
112 tmp = wrapper::vmax(const_0, vin);
113 break;
114 case ActivationLayerInfo::ActivationFunction::BOUNDED_RELU:
115 tmp = wrapper::vmin(va, wrapper::vmax(const_0, vin));
116 break;
117 case ActivationLayerInfo::ActivationFunction::LU_BOUNDED_RELU:
118 tmp = wrapper::vmin(va, wrapper::vmax(vb, vin));
119 break;
120 case ActivationLayerInfo::ActivationFunction::LEAKY_RELU:
121 tmp = wrapper::vbsl(wrapper::vcgt(vin, const_0), vin, wrapper::vmul(va, vin));
122 break;
123 case ActivationLayerInfo::ActivationFunction::SOFT_RELU:
124 tmp = wrapper::vbsl(wrapper::vcgt(vin, vsoft_relu_thresh), vin, wrapper::vlog(wrapper::vadd(const_1, wrapper::vexpq(vin))));
125 break;
126 case ActivationLayerInfo::ActivationFunction::ELU:
127 tmp = wrapper::vbsl(wrapper::vcge(vin, const_0), vin, wrapper::vmul(va, wrapper::vsub(wrapper::vexpq(vin), const_1)));
128 break;
129 case ActivationLayerInfo::ActivationFunction::SQRT:
130 #ifdef __aarch64__
131 tmp = wrapper::vsqrt(vin);
132 #else /* __aarch64__ */
133 {
134 const auto bitmask = wrapper::vceq(vin, wrapper::vdup_n(0.f, ExactTagType{}));
135 tmp = wrapper::vinv(wrapper::vinvsqrt(wrapper::vadd(vin, mask_float_vector(delta, bitmask))));
136 tmp = mask_float_vector(tmp, wrapper::vnot(bitmask));
137 }
138 #endif /* __aarch64__ */
139 break;
140 case ActivationLayerInfo::ActivationFunction::SQUARE:
141 tmp = wrapper::vmul(vin, vin);
142 break;
143 case ActivationLayerInfo::ActivationFunction::TANH:
144 tmp = wrapper::vmul(va, wrapper::vtanh(wrapper::vmul(vb, vin)));
145 break;
146 case ActivationLayerInfo::ActivationFunction::IDENTITY:
147 tmp = vin;
148 break;
149 case ActivationLayerInfo::ActivationFunction::HARD_SWISH:
150 tmp = wrapper::vmul(vin, wrapper::vmul(const_inv_6, wrapper::vmin(const_6, wrapper::vmax(const_0, wrapper::vadd(vin, const_3)))));
151 break;
152 case ActivationLayerInfo::ActivationFunction::SWISH:
153 tmp = wrapper::vmul(vin, wrapper::vinv(wrapper::vadd(const_1, wrapper::vexpq(wrapper::vneg(wrapper::vmul(va, vin))))));
154 break;
155 #ifdef __aarch64__
156 case ActivationLayerInfo::ActivationFunction::GELU:
157 tmp = wrapper::vmul(vin, wrapper::vmul(const_inv_2, wrapper::vadd(const_1, wrapper::verf(wrapper::vmul(vin, const_inv_sqrt_2)))));
158 break;
159 #endif /* __aarch64__ */
160 default:
161 ARM_COMPUTE_ERROR("Unsupported activation function");
162 }
163 wrapper::vstore(output_ptr + x, tmp);
164 }
165 // Compute left-over elements
166 for(; x < window_end_x; ++x)
167 {
168 const T in = *(reinterpret_cast<const T *>(input_ptr + x));
169 T tmp;
170 switch(act)
171 {
172 case ActivationLayerInfo::ActivationFunction::ABS:
173 tmp = std::abs(in);
174 break;
175 case ActivationLayerInfo::ActivationFunction::LINEAR:
176 tmp = a * in + b;
177 break;
178 case ActivationLayerInfo::ActivationFunction::LOGISTIC:
179 tmp = static_cast<T>(1) / (static_cast<T>(1) + std::exp(-in));
180 break;
181 case ActivationLayerInfo::ActivationFunction::RELU:
182 tmp = std::max<T>(static_cast<T>(0), in);
183 break;
184 case ActivationLayerInfo::ActivationFunction::BOUNDED_RELU:
185 tmp = std::min<T>(a, std::max(static_cast<T>(0), in));
186 break;
187 case ActivationLayerInfo::ActivationFunction::LU_BOUNDED_RELU:
188 tmp = std::min<T>(a, std::max<T>(b, in));
189 break;
190 case ActivationLayerInfo::ActivationFunction::LEAKY_RELU:
191 tmp = (in > 0) ? in : a * in;
192 break;
193 case ActivationLayerInfo::ActivationFunction::SOFT_RELU:
194 tmp = (in > soft_relu_thresh) ? in : std::log(static_cast<T>(1) + std::exp(in));
195 break;
196 case ActivationLayerInfo::ActivationFunction::ELU:
197 tmp = (in >= 0) ? in : a * (std::exp(in) - 1);
198 break;
199 case ActivationLayerInfo::ActivationFunction::SQRT:
200 tmp = std::sqrt(in);
201 break;
202 case ActivationLayerInfo::ActivationFunction::SQUARE:
203 tmp = in * in;
204 break;
205 case ActivationLayerInfo::ActivationFunction::TANH:
206 tmp = a * std::tanh(b * in);
207 break;
208 case ActivationLayerInfo::ActivationFunction::IDENTITY:
209 tmp = in;
210 break;
211 case ActivationLayerInfo::ActivationFunction::HARD_SWISH:
212 tmp = in * ((std::min(std::max((in + 3), 0.0f), 6.0f)) * 0.166666667f);
213 break;
214 case ActivationLayerInfo::ActivationFunction::SWISH:
215 tmp = in / (static_cast<T>(1) + std::exp(-a*in));
216 break;
217 case ActivationLayerInfo::ActivationFunction::GELU:
218 tmp = in * static_cast<T>(0.5f * (1.0f + erff(static_cast<float>(in) / 1.41421356237f)));
219 break;
220 default:
221 ARM_COMPUTE_ERROR("Unsupported activation function");
222 }
223 *(output_ptr + x) = tmp;
224 }
225 },
226 input, output);
227 }
228 } // namespace cpu
229 } // namespace arm_compute
230