add some code

managed_components/espressif__esp-dsp/modules/math/sqrt/float/dsps_sqrt_f32_ansi.c

@@ -0,0 +1,56 @@
+// Copyright 2018-2019 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "dsps_sqrt.h"
+#include <math.h>
+
+
+inline float dsps_sqrtf_f32_ansi(float f)
+{
+    int result;
+    int *f_ptr = (int *)&f;
+    result = 0x1fbb4000 + (*f_ptr >> 1);
+    const int *p = &result;
+    float *f_result = (float *)p;
+    return *f_result;
+}
+
+esp_err_t dsps_sqrt_f32_ansi(const float *input, float *output, int len)
+{
+    if (NULL == input) {
+        return ESP_ERR_DSP_PARAM_OUTOFRANGE;
+    }
+    if (NULL == output) {
+        return ESP_ERR_DSP_PARAM_OUTOFRANGE;
+    }
+
+    for (int i = 0 ; i < len ; i++) {
+        output[i] = dsps_sqrtf_f32_ansi(input[i]);
+    }
+    return ESP_OK;
+}
+
+float dsps_inverted_sqrtf_f32_ansi(float data )
+{
+    const float x2 = data * 0.5F;
+    const float threehalfs = 1.5F;
+
+    union {
+        float f;
+        uint32_t i;
+    } conv = {data}; // member 'f' set to value of 'data'.
+    conv.i  = 0x5f3759df - ( conv.i >> 1 );
+    conv.f  *= ( threehalfs - ( x2 * conv.f * conv.f ) );
+    return conv.f;
+}

managed_components/espressif__esp-dsp/modules/math/sqrt/include/dsps_sqrt.h

@@ -0,0 +1,91 @@
+// Copyright 2018-2019 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef _dsps_sqrt_H_
+#define _dsps_sqrt_H_
+#include "dsp_err.h"
+
+
+#ifdef __cplusplus
+extern "C"
+{
+#endif
+
+/**@{*/
+/**
+ * @brief   square root approximation
+ *
+ * The function takes square root approximation
+ * x[i] ~ sqrt(y[i]); i=[0..len)
+ * The implementation use ANSI C and could be compiled and run on any platform
+ *
+ * @param[in] input: input array
+ * @param output: output array
+ * @param len: amount of operations for arrays
+ *
+ * @return
+ *      - ESP_OK on success
+ *      - One of the error codes from DSP library
+ */
+esp_err_t dsps_sqrt_f32_ansi(const float *input, float *output, int len);
+//esp_err_t dsps_sqrt_s32_ansi(const int32_t *input, int16_t *output, int len);
+
+/**@{*/
+/**
+ * @brief   square root approximation
+ *
+ * The function takes square root approximation
+ * x ~ sqrt(y);
+ * The implementation use ANSI C and could be compiled and run on any platform
+ *
+ * @param[in] data: input value
+ *
+ * @return
+ *      - square root value
+ */
+float dsps_sqrtf_f32_ansi(const float data);
+
+
+/**@{*/
+/**
+ * @brief   inverted square root approximation
+ *
+ * The function takes inverted square root approximation
+ * x ~ 1/sqrt(y);
+ * The implementation use ANSI C and could be compiled and run on any platform
+ *
+ * @param[in] data: input value
+ *
+ * @return
+ *      - inverted square root value
+ */
+float dsps_inverted_sqrtf_f32_ansi(float data );
+/**@}*/
+
+#ifdef __cplusplus
+}
+#endif
+
+
+#ifdef CONFIG_DSP_OPTIMIZED
+#define dsps_sqrt_f32 dsps_sqrt_f32_ansi
+#define dsps_sqrtf_f32 dsps_sqrtf_f32_ansi
+#define dsps_inverted_sqrtf_f32 dsps_inverted_sqrtf_f32_ansi
+#else
+#define dsps_sqrt_f32 dsps_sqrt_f32_ansi
+#define dsps_sqrtf_f32 dsps_sqrtf_f32_ansi
+#define dsps_inverted_sqrtf_f32 dsps_inverted_sqrtf_f32_ansi
+#endif
+
+#endif // _dsps_sqrt_H_

managed_components/espressif__esp-dsp/modules/math/sqrt/test/test_dsps_sqrt_f32_ansi.c

@@ -0,0 +1,81 @@
+// Copyright 2018-2023 Espressif Systems (Shanghai) PTE LTD
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include <string.h>
+#include "unity.h"
+#include "dsp_platform.h"
+#include "esp_log.h"
+
+#include "dsp_tests.h"
+#include "dsps_sqrt.h"
+#include "esp_attr.h"
+
+static const char *TAG = "dsps_sqrt";
+
+TEST_CASE("dsps_sqrtf_f32_ansi functionality", "[dsps]")
+{
+    float max_err = -1000;
+    float max_value = 0;
+    float min_err = 0;
+    float min_value = (float)INT32_MAX;
+    int test_points = 100000;
+    for (size_t i = 0; i < test_points; i++) {
+        float test_value = rand();
+        // if (test_value > max_value) max_value = test_value;
+        // if (test_value < min_value) min_value = test_value;
+        float x = sqrtf(test_value);
+        float y = dsps_sqrtf_f32(test_value);
+        float error = 20 * log10f(fabs((x - y) / x) + 0.000001);
+        if (error > max_err) {
+            max_err = error;
+            max_value = test_value;
+        }
+        if (error < min_err) {
+            min_err = error;
+            min_value = test_value;
+        }
+        if (error > -25) {
+            ESP_LOGE(TAG, "dsps_sqrtf_f32_ansi: error = %f dB,  value = %f (0x%8.8x)\n", error, test_value, (int)test_value);
+            TEST_ASSERT_EQUAL(x, y);
+        }
+    }
+    ESP_LOGI(TAG, "dsps_sqrtf_f32_ansi: max error = %f dB,   min error = %f dB, max_value = %f (0x%8.8x), min_value = %f (0x%8.8x)\n", max_err, min_err, max_value, (int)max_value, min_value, (int)min_value);
+}
+
+TEST_CASE("dsps_sqrt_f32_ansi functionality", "[dsps]")
+{
+    int n = 256;
+    float *x = (float *)malloc(sizeof(float) * n);
+    float *result = (float *)malloc(sizeof(float) * n);
+    float *y = (float *)malloc(sizeof(float) * n);
+    for (int i = 0 ; i < n ; i++) {
+        y[i] = i * 10;
+        x[i] = y[i] * y[i];
+    }
+    unsigned int start_b = dsp_get_cpu_cycle_count();
+    dsps_sqrt_f32_ansi(x, result, n);
+    float cycles = dsp_get_cpu_cycle_count() - start_b;
+
+    for (int i = 0 ; i < n ; i++) {
+        //printf("Result[%i] = %f, expected = %f,  diff = %f\n", i, result[i], y[i], 20*logf(fabs((result[i] - y[i])/y[i]) + 0.000001));
+        float error = 20 * log10f(fabs((result[i] - y[i]) / y[i]) + 0.000001);
+        if (error > -25) {
+            TEST_ASSERT_EQUAL(result[i], y[i]);
+        }
+    }
+    ESP_LOGI(TAG, "dsps_sqrt_f32_ansi - %f cycles for %i samples \n", cycles, n);
+    free(x);
+    free(y);
+    free(result);
+}