/* -*- c++ -*- */
/*
 * Copyright 2012, 2014 Free Software Foundation, Inc.
 *
 * This file is part of VOLK
 *
 * SPDX-License-Identifier: GPL-3.0-or-later
 */

/*!
 * \page volk_32f_s32f_power_32f
 *
 * \b Overview
 *
 * Takes each input vector value to the specified power and stores the
 * results in the return vector.
 *
 * <b>Dispatcher Prototype</b>
 * \code
 * void volk_32f_s32f_power_32f(float* cVector, const float* aVector, const float power,
 * unsigned int num_points) \endcode
 *
 * \b Inputs
 * \li aVector: The input vector of floats.
 * \li power: The power to raise the input value to.
 * \li num_points: The number of data points.
 *
 * \b Outputs
 * \li cVector: The output vector.
 *
 * \b Example
 * Square the numbers (0,9)
 * \code
 *   int N = 10;
 *   unsigned int alignment = volk_get_alignment();
 *   float* increasing = (float*)volk_malloc(sizeof(float)*N, alignment);
 *   float* out = (float*)volk_malloc(sizeof(float)*N, alignment);
 *
 *
 *   for(unsigned int ii = 0; ii < N; ++ii){
 *       increasing[ii] = (float)ii;
 *   }
 *
 *   // Normalize by the smallest delta (0.2 in this example)
 *   float scale = 2.0f;
 *
 *   volk_32f_s32f_power_32f(out, increasing, scale, N);
 *
 *   for(unsigned int ii = 0; ii < N; ++ii){
 *       printf("out[%u] = %f\n", ii, out[ii]);
 *   }
 *
 *   volk_free(increasing);
 *   volk_free(out);
 * \endcode
 */

#ifndef INCLUDED_volk_32f_s32f_power_32f_a_H
#define INCLUDED_volk_32f_s32f_power_32f_a_H

#include <inttypes.h>
#include <math.h>
#include <stdio.h>

#ifdef LV_HAVE_SSE4_1
#include <tmmintrin.h>

#ifdef LV_HAVE_LIB_SIMDMATH
#include <simdmath.h>
#endif /* LV_HAVE_LIB_SIMDMATH */

static inline void volk_32f_s32f_power_32f_a_sse4_1(float* cVector,
                                                    const float* aVector,
                                                    const float power,
                                                    unsigned int num_points)
{
    unsigned int number = 0;

    float* cPtr = cVector;
    const float* aPtr = aVector;

#ifdef LV_HAVE_LIB_SIMDMATH
    const unsigned int quarterPoints = num_points / 4;
    __m128 vPower = _mm_set_ps1(power);
    __m128 zeroValue = _mm_setzero_ps();
    __m128 signMask;
    __m128 negatedValues;
    __m128 negativeOneToPower = _mm_set_ps1(powf(-1, power));
    __m128 onesMask = _mm_set_ps1(1);

    __m128 aVal, cVal;
    for (; number < quarterPoints; number++) {

        aVal = _mm_load_ps(aPtr);
        signMask = _mm_cmplt_ps(aVal, zeroValue);
        negatedValues = _mm_sub_ps(zeroValue, aVal);
        aVal = _mm_blendv_ps(aVal, negatedValues, signMask);

        // powf4 doesn't support negative values in the base, so we mask them off and then
        // apply the negative after
        cVal = powf4(aVal, vPower); // Takes each input value to the specified power

        cVal = _mm_mul_ps(_mm_blendv_ps(onesMask, negativeOneToPower, signMask), cVal);

        _mm_store_ps(cPtr, cVal); // Store the results back into the C container

        aPtr += 4;
        cPtr += 4;
    }

    number = quarterPoints * 4;
#endif /* LV_HAVE_LIB_SIMDMATH */

    for (; number < num_points; number++) {
        *cPtr++ = powf((*aPtr++), power);
    }
}

#endif /* LV_HAVE_SSE4_1 */


#ifdef LV_HAVE_SSE
#include <xmmintrin.h>

#ifdef LV_HAVE_LIB_SIMDMATH
#include <simdmath.h>
#endif /* LV_HAVE_LIB_SIMDMATH */

static inline void volk_32f_s32f_power_32f_a_sse(float* cVector,
                                                 const float* aVector,
                                                 const float power,
                                                 unsigned int num_points)
{
    unsigned int number = 0;

    float* cPtr = cVector;
    const float* aPtr = aVector;

#ifdef LV_HAVE_LIB_SIMDMATH
    const unsigned int quarterPoints = num_points / 4;
    __m128 vPower = _mm_set_ps1(power);
    __m128 zeroValue = _mm_setzero_ps();
    __m128 signMask;
    __m128 negatedValues;
    __m128 negativeOneToPower = _mm_set_ps1(powf(-1, power));
    __m128 onesMask = _mm_set_ps1(1);

    __m128 aVal, cVal;
    for (; number < quarterPoints; number++) {

        aVal = _mm_load_ps(aPtr);
        signMask = _mm_cmplt_ps(aVal, zeroValue);
        negatedValues = _mm_sub_ps(zeroValue, aVal);
        aVal =
            _mm_or_ps(_mm_andnot_ps(signMask, aVal), _mm_and_ps(signMask, negatedValues));

        // powf4 doesn't support negative values in the base, so we mask them off and then
        // apply the negative after
        cVal = powf4(aVal, vPower); // Takes each input value to the specified power

        cVal = _mm_mul_ps(_mm_or_ps(_mm_andnot_ps(signMask, onesMask),
                                    _mm_and_ps(signMask, negativeOneToPower)),
                          cVal);

        _mm_store_ps(cPtr, cVal); // Store the results back into the C container

        aPtr += 4;
        cPtr += 4;
    }

    number = quarterPoints * 4;
#endif /* LV_HAVE_LIB_SIMDMATH */

    for (; number < num_points; number++) {
        *cPtr++ = powf((*aPtr++), power);
    }
}

#endif /* LV_HAVE_SSE */


#ifdef LV_HAVE_GENERIC

static inline void volk_32f_s32f_power_32f_generic(float* cVector,
                                                   const float* aVector,
                                                   const float power,
                                                   unsigned int num_points)
{
    float* cPtr = cVector;
    const float* aPtr = aVector;
    unsigned int number = 0;

    for (number = 0; number < num_points; number++) {
        *cPtr++ = powf((*aPtr++), power);
    }
}
#endif /* LV_HAVE_GENERIC */


#endif /* INCLUDED_volk_32f_s32f_power_32f_a_H */
