1 /*
2  * Copyright (c) 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 #if defined(__aarch64__) && defined(__ARM_FEATURE_FP16_VECTOR_ARITHMETIC)
25 
26 #include <arm_neon.h>
27 #include <cstddef>
28 
29 namespace arm_conv {
30 namespace winograd {
31 namespace input_transform {
32 
a64_fp16_6x6(const unsigned int n_channels,const __fp16 * const input_base,const size_t input_row_stride,const size_t input_col_stride,__fp16 * outptr,const size_t matrix_stride)33 void a64_fp16_6x6(
34     const unsigned int n_channels,
35     const __fp16* const input_base,
36     const size_t input_row_stride,
37     const size_t input_col_stride,
38     __fp16* outptr,
39     const size_t matrix_stride
40 )
41 {
42     constexpr int inner_tile_rows = 6;
43     constexpr int inner_tile_cols = 6;
44 
45     // Get pointers into the input tile
46     const __fp16 *x_ptrs[inner_tile_rows][inner_tile_cols];
47     for (int i = 0, xi = 0; i < inner_tile_rows; i++, xi++)
48     {
49         // Get a pointer into the row
50         const __fp16* const row_ptr = input_base + xi*input_row_stride;
51 
52         for (int j = 0, xj = 0; j < inner_tile_cols; j++, xj++)
53         {
54             x_ptrs[i][j] = row_ptr + xj*input_col_stride;
55         }
56     }
57 
58     // Matrices used/computed in this kernel.
59     __fp16 x[inner_tile_rows][inner_tile_cols];
60     __fp16 XTx[inner_tile_rows][inner_tile_cols];
61     __fp16 U[inner_tile_rows][inner_tile_cols];
62     for (int i = 0; i < inner_tile_rows; i++)
63     {
64         for (int j = 0; j < inner_tile_cols; j++)
65         {
66             x[i][j] = XTx[i][j] = 0.0f;
67         }
68     }
69 
70     // Perform the Winograd input transformation for each channel in the input
71     // tensor.
72     int channels_remaining = n_channels;
73     for (; channels_remaining >= 8; channels_remaining -= 8)
74     {
75         // Matrices used/computed in this kernel
76         float16x8_t x[inner_tile_rows][inner_tile_cols];
77         float16x8_t XTx[inner_tile_rows][inner_tile_cols];
78         float16x8_t U[inner_tile_rows][inner_tile_cols];
79         for (int i = 0; i < inner_tile_rows; i++)
80         {
81             for (int j = 0; j < inner_tile_cols; j++)
82             {
83                 x[i][j] = vdupq_n_f16(0.0f);
84                 XTx[i][j] = vdupq_n_f16(0.0f);
85             }
86         }
87 
88         // Read a 6x6 tile in the Winograd domain
89         for (int i = 0; i < inner_tile_rows; i++)
90         {
91             for (int j = 0; j < inner_tile_cols; j++)
92             {
93                 x[i][j] = vld1q_f16(x_ptrs[i][j]);
94                 x_ptrs[i][j] += 8;
95             }
96         }
97 
98         // Compute XT . x
99         for (int j = 0; j < inner_tile_cols; j++)
100         {
101             // XTx[0][j] =  4*x[0][j] + -5*x[2][j] +  1*x[4][j];
102             XTx[0][j] = vsubq_f16(vaddq_f16(x[4][j], vmulq_f16(x[0][j], vdupq_n_f16(4.0f))), vmulq_f16(x[2][j], vdupq_n_f16(5.0f)));
103 
104             // XTx[1][j] = -4*x[1][j] + -4*x[2][j] +  1*x[3][j] +  1*x[4][j];
105             XTx[1][j] = vsubq_f16(vaddq_f16(x[3][j], x[4][j]), vmulq_f16(vaddq_f16(x[1][j], x[2][j]),  vdupq_n_f16(4.0f)));
106 
107             // XTx[2][j] =  4*x[1][j] + -4*x[2][j] + -1*x[3][j] +  1*x[4][j];
108             XTx[2][j] = vaddq_f16(vsubq_f16(x[4][j], x[3][j]), vmulq_f16(vsubq_f16(x[1][j], x[2][j]), vdupq_n_f16(4.0f)));
109 
110             // XTx[3][j] = -2*x[1][j] + -1*x[2][j] +  2*x[3][j] +  1*x[4][j];
111             XTx[3][j] = vaddq_f16(vsubq_f16(x[4][j], x[2][j]), vmulq_f16(vsubq_f16(x[3][j], x[1][j]), vdupq_n_f16(2.0f)));
112 
113             // XTx[4][j] =  2*x[1][j] + -1*x[2][j] + -2*x[3][j] +  1*x[4][j];
114             XTx[4][j] = vaddq_f16(vsubq_f16(x[4][j], x[2][j]), vmulq_f16(vsubq_f16(x[1][j], x[3][j]), vdupq_n_f16(2.0f)));
115 
116             // XTx[5][j] =  4*x[1][j] + -5*x[3][j] +  1*x[5][j];
117             XTx[5][j] = vsubq_f16(vaddq_f16(x[5][j], vmulq_f16(x[1][j], vdupq_n_f16(4.0f))), vmulq_f16(x[3][j], vdupq_n_f16(5.0f)));
118         }
119 
120         // Compute U = XT . x . X
121         for (int i = 0; i < inner_tile_rows; i++)
122         {
123             // U[i][0] =  4*XTx[i][0] + -5*XTx[i][2] +  1*XTx[i][4];
124             U[i][0] = vsubq_f16(vaddq_f16(XTx[i][4], vmulq_f16(XTx[i][0], vdupq_n_f16(4.0f))), vmulq_f16(XTx[i][2], vdupq_n_f16(5.0f)));
125 
126             // U[i][1] = -4*XTx[i][1] + -4*XTx[i][2] +  1*XTx[i][3] +  1*XTx[i][4];
127             U[i][1] = vsubq_f16(vaddq_f16(XTx[i][3], XTx[i][4]), vmulq_f16(vaddq_f16(XTx[i][1], XTx[i][2]), vdupq_n_f16(4.0f)));
128 
129             // U[i][2] =  4*XTx[i][1] + -4*XTx[i][2] + -1*XTx[i][3] +  1*XTx[i][4];
130             U[i][2] = vaddq_f16(vsubq_f16(XTx[i][4], XTx[i][3]), vmulq_f16(vsubq_f16(XTx[i][1], XTx[i][2]), vdupq_n_f16(4.0f)));
131 
132             // U[i][3] = -2*XTx[i][1] + -1*XTx[i][2] +  2*XTx[i][3] +  1*XTx[i][4];
133             U[i][3] = vaddq_f16(vsubq_f16(XTx[i][4], XTx[i][2]), vmulq_f16(vsubq_f16(XTx[i][3], XTx[i][1]), vdupq_n_f16(2.0f)));
134 
135             // U[i][4] =  2*XTx[i][1] + -1*XTx[i][2] + -2*XTx[i][3] +  1*XTx[i][4];
136             U[i][4] = vaddq_f16(vsubq_f16(XTx[i][4], XTx[i][2]), vmulq_f16(vsubq_f16(XTx[i][1], XTx[i][3]), vdupq_n_f16(2.0f)));
137 
138             // U[i][5] =  4*XTx[i][1] + -5*XTx[i][3] +  1*XTx[i][5];
139             U[i][5] = vsubq_f16(vaddq_f16(XTx[i][5], vmulq_f16(XTx[i][1], vdupq_n_f16(4.0f))), vmulq_f16(XTx[i][3], vdupq_n_f16(5.0f)));
140         }
141 
142         // Store the transformed matrix
143         for (int i = 0, m = 0; i < inner_tile_rows; i++)
144         {
145             for (int j = 0; j < inner_tile_cols; j++, m++)
146             {
147                 vst1q_f16(outptr + m*matrix_stride, U[i][j]);
148             }
149         }
150         outptr += 8;
151     }
152     for (; channels_remaining >= 4; channels_remaining -= 4)
153     {
154         // Matrices used/computed in this kernel
155         float16x4_t x[inner_tile_rows][inner_tile_cols];
156         float16x4_t XTx[inner_tile_rows][inner_tile_cols];
157         float16x4_t U[inner_tile_rows][inner_tile_cols];
158         for (int i = 0; i < inner_tile_rows; i++)
159         {
160             for (int j = 0; j < inner_tile_cols; j++)
161             {
162                 x[i][j] = vdup_n_f16(0.0f);
163                 XTx[i][j] = vdup_n_f16(0.0f);
164             }
165         }
166 
167         // Read a 6x6 tile in the Winograd domain
168         for (int i = 0; i < inner_tile_rows; i++)
169         {
170             for (int j = 0; j < inner_tile_cols; j++)
171             {
172                 x[i][j] = vld1_f16(x_ptrs[i][j]);
173                 x_ptrs[i][j] += 4;
174             }
175         }
176 
177         // Compute XT . x
178         for (int j = 0; j < inner_tile_cols; j++)
179         {
180             // XTx[0][j] =  4*x[0][j] + -5*x[2][j] +  1*x[4][j];
181             XTx[0][j] = vsub_f16(vadd_f16(x[4][j], vmul_f16(x[0][j], vdup_n_f16(4.0f))), vmul_f16(x[2][j], vdup_n_f16(5.0f)));
182 
183             // XTx[1][j] = -4*x[1][j] + -4*x[2][j] +  1*x[3][j] +  1*x[4][j];
184             XTx[1][j] = vsub_f16(vadd_f16(x[3][j], x[4][j]), vmul_f16(vadd_f16(x[1][j], x[2][j]),  vdup_n_f16(4.0f)));
185 
186             // XTx[2][j] =  4*x[1][j] + -4*x[2][j] + -1*x[3][j] +  1*x[4][j];
187             XTx[2][j] = vadd_f16(vsub_f16(x[4][j], x[3][j]), vmul_f16(vsub_f16(x[1][j], x[2][j]), vdup_n_f16(4.0f)));
188 
189             // XTx[3][j] = -2*x[1][j] + -1*x[2][j] +  2*x[3][j] +  1*x[4][j];
190             XTx[3][j] = vadd_f16(vsub_f16(x[4][j], x[2][j]), vmul_f16(vsub_f16(x[3][j], x[1][j]), vdup_n_f16(2.0f)));
191 
192             // XTx[4][j] =  2*x[1][j] + -1*x[2][j] + -2*x[3][j] +  1*x[4][j];
193             XTx[4][j] = vadd_f16(vsub_f16(x[4][j], x[2][j]), vmul_f16(vsub_f16(x[1][j], x[3][j]), vdup_n_f16(2.0f)));
194 
195             // XTx[5][j] =  4*x[1][j] + -5*x[3][j] +  1*x[5][j];
196             XTx[5][j] = vsub_f16(vadd_f16(x[5][j], vmul_f16(x[1][j], vdup_n_f16(4.0f))), vmul_f16(x[3][j], vdup_n_f16(5.0f)));
197         }
198 
199         // Compute U = XT . x . X
200         for (int i = 0; i < inner_tile_rows; i++)
201         {
202             // U[i][0] =  4*XTx[i][0] + -5*XTx[i][2] +  1*XTx[i][4];
203             U[i][0] = vsub_f16(vadd_f16(XTx[i][4], vmul_f16(XTx[i][0], vdup_n_f16(4.0f))), vmul_f16(XTx[i][2], vdup_n_f16(5.0f)));
204 
205             // U[i][1] = -4*XTx[i][1] + -4*XTx[i][2] +  1*XTx[i][3] +  1*XTx[i][4];
206             U[i][1] = vsub_f16(vadd_f16(XTx[i][3], XTx[i][4]), vmul_f16(vadd_f16(XTx[i][1], XTx[i][2]), vdup_n_f16(4.0f)));
207 
208             // U[i][2] =  4*XTx[i][1] + -4*XTx[i][2] + -1*XTx[i][3] +  1*XTx[i][4];
209             U[i][2] = vadd_f16(vsub_f16(XTx[i][4], XTx[i][3]), vmul_f16(vsub_f16(XTx[i][1], XTx[i][2]), vdup_n_f16(4.0f)));
210 
211             // U[i][3] = -2*XTx[i][1] + -1*XTx[i][2] +  2*XTx[i][3] +  1*XTx[i][4];
212             U[i][3] = vadd_f16(vsub_f16(XTx[i][4], XTx[i][2]), vmul_f16(vsub_f16(XTx[i][3], XTx[i][1]), vdup_n_f16(2.0f)));
213 
214             // U[i][4] =  2*XTx[i][1] + -1*XTx[i][2] + -2*XTx[i][3] +  1*XTx[i][4];
215             U[i][4] = vadd_f16(vsub_f16(XTx[i][4], XTx[i][2]), vmul_f16(vsub_f16(XTx[i][1], XTx[i][3]), vdup_n_f16(2.0f)));
216 
217             // U[i][5] =  4*XTx[i][1] + -5*XTx[i][3] +  1*XTx[i][5];
218             U[i][5] = vsub_f16(vadd_f16(XTx[i][5], vmul_f16(XTx[i][1], vdup_n_f16(4.0f))), vmul_f16(XTx[i][3], vdup_n_f16(5.0f)));
219         }
220 
221         // Store the transformed matrix
222         for (int i = 0, m = 0; i < inner_tile_rows; i++)
223         {
224             for (int j = 0; j < inner_tile_cols; j++, m++)
225             {
226                 vst1_f16(outptr + m*matrix_stride, U[i][j]);
227             }
228         }
229         outptr += 4;
230     }
231     for (; channels_remaining; channels_remaining--)
232     {
233         // Load x
234         for (int i = 0; i < inner_tile_rows; i++)
235         {
236             for (int j = 0; j < inner_tile_cols; j++)
237             {
238                 x[i][j] = *(x_ptrs[i][j]++);
239             }
240         }
241 
242         // Compute XT . x
243         for (int j = 0; j < inner_tile_cols; j++)
244         {
245             XTx[0][j] =  4*x[0][j] + -5*x[2][j] +  1*x[4][j];
246             XTx[1][j] = -4*x[1][j] + -4*x[2][j] +  1*x[3][j] +  1*x[4][j];
247             XTx[2][j] =  4*x[1][j] + -4*x[2][j] + -1*x[3][j] +  1*x[4][j];
248             XTx[3][j] = -2*x[1][j] + -1*x[2][j] +  2*x[3][j] +  1*x[4][j];
249             XTx[4][j] =  2*x[1][j] + -1*x[2][j] + -2*x[3][j] +  1*x[4][j];
250             XTx[5][j] =  4*x[1][j] + -5*x[3][j] +  1*x[5][j];
251         }
252 
253         // Compute U = XT . x . X
254         for (int i = 0; i < inner_tile_rows; i++)
255         {
256             U[i][0] =  4*XTx[i][0] + -5*XTx[i][2] +  1*XTx[i][4];
257             U[i][1] = -4*XTx[i][1] + -4*XTx[i][2] +  1*XTx[i][3] +  1*XTx[i][4];
258             U[i][2] =  4*XTx[i][1] + -4*XTx[i][2] + -1*XTx[i][3] +  1*XTx[i][4];
259             U[i][3] = -2*XTx[i][1] + -1*XTx[i][2] +  2*XTx[i][3] +  1*XTx[i][4];
260             U[i][4] =  2*XTx[i][1] + -1*XTx[i][2] + -2*XTx[i][3] +  1*XTx[i][4];
261             U[i][5] =  4*XTx[i][1] + -5*XTx[i][3] +  1*XTx[i][5];
262         }
263 
264         // Store the transformed matrix
265         for (int i = 0, m = 0; i < inner_tile_rows; i++)
266         {
267             for (int j = 0; j < inner_tile_cols; j++, m++)
268             {
269                 *(outptr + m*matrix_stride) = U[i][j];
270             }
271         }
272         outptr++;
273     }
274 }
275 
276 }  // namespace input_transform
277 }  // namespace winograd
278 }  // namespace arm_conv
279 
280 #endif // defined(__aarch64__) && defined(__ARM_FEATURE_FP16_VECTOR_ARITHMETIC)
281