1 /*
2 * SPDX-FileCopyrightText: Copyright 2024 Arm Limited and/or its affiliates <open-source-office.com>
3 *
4 * SPDX-License-Identifier: Apache-2.0
5 *
6 * Licensed under the Apache License, Version 2.0 (the License); you may
7 * not use this file except in compliance with the License.
8 * You may obtain a copy of the License at
9 *
10 * www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing, software
13 * distributed under the License is distributed on an AS IS BASIS, WITHOUT
14 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 * See the License for the specific language governing permissions and
16 * limitations under the License.
17 */
18
19 /* ----------------------------------------------------------------------
20 * Project: CMSIS NN Library
21 * Title: arm_nn_lstm_step_s16.c
22 * Description: Update LSTM function for a single iteration step.
23 *
24 * $Date: 26 March 2024
25 * $Revision: V.1.0.0
26 *
27 * Target : Arm(R) M-Profile Architecture
28 *
29 * -------------------------------------------------------------------- */
30 #include "arm_nnfunctions.h"
31 #include "arm_nnsupportfunctions.h"
32
33 /**
34 * @ingroup groupSupport
35 */
36
37 /**
38 * @addtogroup supportLSTM
39 * @{
40 */
41
42 /*
43 * Calculate the output state tensor of an LSTM step, s16 input/output/weights and s16 internal buffers version.
44 * Refer to header file for details.
45 */
arm_nn_lstm_step_s16(const int16_t * data_in,const int16_t * hidden_in,int16_t * hidden_out,const cmsis_nn_lstm_params * params,cmsis_nn_lstm_context * buffers,const int32_t batch_offset)46 arm_cmsis_nn_status arm_nn_lstm_step_s16(const int16_t *data_in,
47 const int16_t *hidden_in,
48 int16_t *hidden_out,
49 const cmsis_nn_lstm_params *params,
50 cmsis_nn_lstm_context *buffers,
51 const int32_t batch_offset)
52 {
53 int16_t *forget_gate = buffers->temp1;
54 int16_t *input_gate = buffers->temp1;
55 int16_t *cell_gate = buffers->temp2;
56 int16_t *output_gate = buffers->temp1;
57 int16_t *hidden_temp = buffers->temp2;
58
59 int16_t *cell_state = buffers->cell_state;
60
61 arm_nn_lstm_calculate_gate_s16(data_in, hidden_in, ¶ms->forget_gate, params, forget_gate, batch_offset);
62
63 // Calculate first term of cell state in place early to maximise reuse of scratch-buffers
64 arm_elementwise_mul_s16(forget_gate,
65 cell_state,
66 0,
67 0,
68 cell_state,
69 0,
70 params->forget_to_cell_multiplier,
71 params->forget_to_cell_shift,
72 NN_Q15_MIN,
73 NN_Q15_MAX,
74 params->hidden_size * params->batch_size);
75
76 arm_nn_lstm_calculate_gate_s16(data_in, hidden_in, ¶ms->input_gate, params, input_gate, batch_offset);
77
78 arm_nn_lstm_calculate_gate_s16(data_in, hidden_in, ¶ms->cell_gate, params, cell_gate, batch_offset);
79
80 // Reminder of cell state calculation, multiply and add to previous result.
81 arm_elementwise_mul_acc_s16(forget_gate,
82 cell_gate,
83 0,
84 0,
85 cell_state,
86 0,
87 params->input_to_cell_multiplier,
88 params->input_to_cell_shift,
89 -params->cell_clip,
90 params->cell_clip,
91 params->hidden_size * params->batch_size);
92
93 arm_nn_lstm_calculate_gate_s16(data_in, hidden_in, ¶ms->output_gate, params, output_gate, batch_offset);
94
95 // Calculate hidden state directly to output.
96 arm_nn_activation_s16(
97 cell_state, hidden_temp, params->hidden_size * params->batch_size, params->cell_scale_power + 12, ARM_TANH);
98 arm_elementwise_mul_s16_batch_offset(output_gate,
99 hidden_temp,
100 hidden_out,
101 params->output_offset,
102 params->output_multiplier,
103 params->output_shift,
104 params->hidden_size,
105 params->batch_size,
106 batch_offset);
107
108 return ARM_CMSIS_NN_SUCCESS;
109 }
110 /**
111 * @} end of supportLSTM group
112 */
113
