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volk_32fc_s32f_power_spectrum_32f.h
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/* -*- c++ -*- */
/*
* Copyright 2012, 2014 Free Software Foundation, Inc.
*
* This file is part of VOLK
*
* SPDX-License-Identifier: LGPL-3.0-or-later
*/
#ifndef INCLUDED_volk_32fc_s32f_power_spectrum_32f_a_H
#define INCLUDED_volk_32fc_s32f_power_spectrum_32f_a_H
#include <inttypes.h>
#include <math.h>
#include <stdio.h>
#ifdef LV_HAVE_GENERIC
static inline void
volk_32fc_s32f_power_spectrum_32f_generic(float* logPowerOutput,
const lv_32fc_t* complexFFTInput,
const float normalizationFactor,
unsigned int num_points)
{
// Calculate the Power of the complex point
const float normFactSq = 1.0 / (normalizationFactor * normalizationFactor);
// Calculate dBm
// 50 ohm load assumption
// 10 * log10 (v^2 / (2 * 50.0 * .001)) = 10 * log10( v^2 * 10)
// 75 ohm load assumption
// 10 * log10 (v^2 / (2 * 75.0 * .001)) = 10 * log10( v^2 * 15)
/*
* For generic reference, the code below is a volk-optimized
* approach that also leverages a faster log2 calculation
* to calculate the log10:
* n*log10(x) = n*log2(x)/log2(10) = (n/log2(10)) * log2(x)
*
* Generic code:
*
* const float real = *inputPtr++ * iNormalizationFactor;
* const float imag = *inputPtr++ * iNormalizationFactor;
* realFFTDataPointsPtr = 10.0*log10f(((real * real) + (imag * imag)) + 1e-20);
* realFFTDataPointsPtr++;
*
*/
// Calc mag^2
volk_32fc_magnitude_squared_32f(logPowerOutput, complexFFTInput, num_points);
// Finish ((real * real) + (imag * imag)) calculation:
volk_32f_s32f_multiply_32f(logPowerOutput, logPowerOutput, normFactSq, num_points);
// The following calculates 10*log10(x) = 10*log2(x)/log2(10) = (10/log2(10))
// * log2(x)
volk_32f_log2_32f(logPowerOutput, logPowerOutput, num_points);
volk_32f_s32f_multiply_32f(
logPowerOutput, logPowerOutput, volk_log2to10factor, num_points);
}
#endif /* LV_HAVE_GENERIC */
#ifdef LV_HAVE_NEON
#include <arm_neon.h>
#include <volk/volk_neon_intrinsics.h>
static inline void
volk_32fc_s32f_power_spectrum_32f_neon(float* logPowerOutput,
const lv_32fc_t* complexFFTInput,
const float normalizationFactor,
unsigned int num_points)
{
float* logPowerOutputPtr = logPowerOutput;
const lv_32fc_t* complexFFTInputPtr = complexFFTInput;
const float iNormalizationFactor = 1.0 / normalizationFactor;
unsigned int number;
unsigned int quarter_points = num_points / 4;
float32x4x2_t fft_vec;
float32x4_t log_pwr_vec;
float32x4_t mag_squared_vec;
const float inv_ln10_10 = 4.34294481903f; // 10.0/ln(10.)
for (number = 0; number < quarter_points; number++) {
// Load
fft_vec = vld2q_f32((float*)complexFFTInputPtr);
// Prefetch next 4
__VOLK_PREFETCH(complexFFTInputPtr + 4);
// Normalize
fft_vec.val[0] = vmulq_n_f32(fft_vec.val[0], iNormalizationFactor);
fft_vec.val[1] = vmulq_n_f32(fft_vec.val[1], iNormalizationFactor);
mag_squared_vec = _vmagnitudesquaredq_f32(fft_vec);
log_pwr_vec = vmulq_n_f32(_vlogq_f32(mag_squared_vec), inv_ln10_10);
// Store
vst1q_f32(logPowerOutputPtr, log_pwr_vec);
// Move pointers ahead
complexFFTInputPtr += 4;
logPowerOutputPtr += 4;
}
// deal with the rest
for (number = quarter_points * 4; number < num_points; number++) {
const float real = lv_creal(*complexFFTInputPtr) * iNormalizationFactor;
const float imag = lv_cimag(*complexFFTInputPtr) * iNormalizationFactor;
*logPowerOutputPtr =
volk_log2to10factor * log2f_non_ieee(((real * real) + (imag * imag)));
complexFFTInputPtr++;
logPowerOutputPtr++;
}
}
#endif /* LV_HAVE_NEON */
#ifdef LV_HAVE_RVV
#include <riscv_vector.h>
#ifndef LOG_POLY_DEGREE
#define LOG_POLY_DEGREE 6
#endif
static inline void volk_32fc_s32f_power_spectrum_32f_rvv(float* logPowerOutput,
const lv_32fc_t* complexFFTInput,
const float normalizationFactor,
unsigned int num_points)
{
size_t vlmax = __riscv_vsetvlmax_e32m2();
#if LOG_POLY_DEGREE == 6
const vfloat32m2_t c5 = __riscv_vfmv_v_f_f32m2(3.1157899f, vlmax);
const vfloat32m2_t c4 = __riscv_vfmv_v_f_f32m2(-3.3241990f, vlmax);
const vfloat32m2_t c3 = __riscv_vfmv_v_f_f32m2(2.5988452f, vlmax);
const vfloat32m2_t c2 = __riscv_vfmv_v_f_f32m2(-1.2315303f, vlmax);
const vfloat32m2_t c1 = __riscv_vfmv_v_f_f32m2(3.1821337e-1f, vlmax);
const vfloat32m2_t c0 = __riscv_vfmv_v_f_f32m2(-3.4436006e-2f, vlmax);
#elif LOG_POLY_DEGREE == 5
const vfloat32m2_t c4 = __riscv_vfmv_v_f_f32m2(2.8882704548164776201f, vlmax);
const vfloat32m2_t c3 = __riscv_vfmv_v_f_f32m2(-2.52074962577807006663f, vlmax);
const vfloat32m2_t c2 = __riscv_vfmv_v_f_f32m2(1.48116647521213171641f, vlmax);
const vfloat32m2_t c1 = __riscv_vfmv_v_f_f32m2(-0.465725644288844778798f, vlmax);
const vfloat32m2_t c0 = __riscv_vfmv_v_f_f32m2(0.0596515482674574969533f, vlmax);
#elif LOG_POLY_DEGREE == 4
const vfloat32m2_t c3 = __riscv_vfmv_v_f_f32m2(2.61761038894603480148f, vlmax);
const vfloat32m2_t c2 = __riscv_vfmv_v_f_f32m2(-1.75647175389045657003f, vlmax);
const vfloat32m2_t c1 = __riscv_vfmv_v_f_f32m2(0.688243882994381274313f, vlmax);
const vfloat32m2_t c0 = __riscv_vfmv_v_f_f32m2(-0.107254423828329604454f, vlmax);
#elif LOG_POLY_DEGREE == 3
const vfloat32m2_t c2 = __riscv_vfmv_v_f_f32m2(2.28330284476918490682f, vlmax);
const vfloat32m2_t c1 = __riscv_vfmv_v_f_f32m2(-1.04913055217340124191f, vlmax);
const vfloat32m2_t c0 = __riscv_vfmv_v_f_f32m2(0.204446009836232697516f, vlmax);
#else
#error
#endif
const vfloat32m2_t cf1 = __riscv_vfmv_v_f_f32m2(1.0f, vlmax);
const vint32m2_t m1 = __riscv_vreinterpret_i32m2(cf1);
const vint32m2_t m2 = __riscv_vmv_v_x_i32m2(0x7FFFFF, vlmax);
const vint32m2_t c127 = __riscv_vmv_v_x_i32m2(127, vlmax);
const float normFactSq = 1.0 / (normalizationFactor * normalizationFactor);
size_t n = num_points;
for (size_t vl; n > 0; n -= vl, complexFFTInput += vl, logPowerOutput += vl) {
vl = __riscv_vsetvl_e32m2(n);
vuint64m4_t vc = __riscv_vle64_v_u64m4((const uint64_t*)complexFFTInput, vl);
vfloat32m2_t vr = __riscv_vreinterpret_f32m2(__riscv_vnsrl(vc, 0, vl));
vfloat32m2_t vi = __riscv_vreinterpret_f32m2(__riscv_vnsrl(vc, 32, vl));
vfloat32m2_t v = __riscv_vfmacc(__riscv_vfmul(vi, vi, vl), vr, vr, vl);
v = __riscv_vfmul(v, normFactSq, vl);
vfloat32m2_t a = __riscv_vfabs(v, vl);
vfloat32m2_t exp = __riscv_vfcvt_f(
__riscv_vsub(__riscv_vsra(__riscv_vreinterpret_i32m2(a), 23, vl), c127, vl),
vl);
vfloat32m2_t frac = __riscv_vreinterpret_f32m2(
__riscv_vor(__riscv_vand(__riscv_vreinterpret_i32m2(v), m2, vl), m1, vl));
vfloat32m2_t mant = c0;
mant = __riscv_vfmadd(mant, frac, c1, vl);
mant = __riscv_vfmadd(mant, frac, c2, vl);
#if LOG_POLY_DEGREE >= 4
mant = __riscv_vfmadd(mant, frac, c3, vl);
#if LOG_POLY_DEGREE >= 5
mant = __riscv_vfmadd(mant, frac, c4, vl);
#if LOG_POLY_DEGREE >= 6
mant = __riscv_vfmadd(mant, frac, c5, vl);
#endif
#endif
#endif
v = __riscv_vfmacc(exp, mant, __riscv_vfsub(frac, cf1, vl), vl);
v = __riscv_vfmul(v, volk_log2to10factor, vl);
__riscv_vse32(logPowerOutput, v, vl);
}
}
#endif /*LV_HAVE_RVV*/
#ifdef LV_HAVE_RVVSEG
#include <riscv_vector.h>
#ifndef LOG_POLY_DEGREE
#define LOG_POLY_DEGREE 6
#endif
static inline void
volk_32fc_s32f_power_spectrum_32f_rvvseg(float* logPowerOutput,
const lv_32fc_t* complexFFTInput,
const float normalizationFactor,
unsigned int num_points)
{
size_t vlmax = __riscv_vsetvlmax_e32m2();
#if LOG_POLY_DEGREE == 6
const vfloat32m2_t c5 = __riscv_vfmv_v_f_f32m2(3.1157899f, vlmax);
const vfloat32m2_t c4 = __riscv_vfmv_v_f_f32m2(-3.3241990f, vlmax);
const vfloat32m2_t c3 = __riscv_vfmv_v_f_f32m2(2.5988452f, vlmax);
const vfloat32m2_t c2 = __riscv_vfmv_v_f_f32m2(-1.2315303f, vlmax);
const vfloat32m2_t c1 = __riscv_vfmv_v_f_f32m2(3.1821337e-1f, vlmax);
const vfloat32m2_t c0 = __riscv_vfmv_v_f_f32m2(-3.4436006e-2f, vlmax);
#elif LOG_POLY_DEGREE == 5
const vfloat32m2_t c4 = __riscv_vfmv_v_f_f32m2(2.8882704548164776201f, vlmax);
const vfloat32m2_t c3 = __riscv_vfmv_v_f_f32m2(-2.52074962577807006663f, vlmax);
const vfloat32m2_t c2 = __riscv_vfmv_v_f_f32m2(1.48116647521213171641f, vlmax);
const vfloat32m2_t c1 = __riscv_vfmv_v_f_f32m2(-0.465725644288844778798f, vlmax);
const vfloat32m2_t c0 = __riscv_vfmv_v_f_f32m2(0.0596515482674574969533f, vlmax);
#elif LOG_POLY_DEGREE == 4
const vfloat32m2_t c3 = __riscv_vfmv_v_f_f32m2(2.61761038894603480148f, vlmax);
const vfloat32m2_t c2 = __riscv_vfmv_v_f_f32m2(-1.75647175389045657003f, vlmax);
const vfloat32m2_t c1 = __riscv_vfmv_v_f_f32m2(0.688243882994381274313f, vlmax);
const vfloat32m2_t c0 = __riscv_vfmv_v_f_f32m2(-0.107254423828329604454f, vlmax);
#elif LOG_POLY_DEGREE == 3
const vfloat32m2_t c2 = __riscv_vfmv_v_f_f32m2(2.28330284476918490682f, vlmax);
const vfloat32m2_t c1 = __riscv_vfmv_v_f_f32m2(-1.04913055217340124191f, vlmax);
const vfloat32m2_t c0 = __riscv_vfmv_v_f_f32m2(0.204446009836232697516f, vlmax);
#else
#error
#endif
const vfloat32m2_t cf1 = __riscv_vfmv_v_f_f32m2(1.0f, vlmax);
const vint32m2_t m1 = __riscv_vreinterpret_i32m2(cf1);
const vint32m2_t m2 = __riscv_vmv_v_x_i32m2(0x7FFFFF, vlmax);
const vint32m2_t c127 = __riscv_vmv_v_x_i32m2(127, vlmax);
const float normFactSq = 1.0 / (normalizationFactor * normalizationFactor);
size_t n = num_points;
for (size_t vl; n > 0; n -= vl, complexFFTInput += vl, logPowerOutput += vl) {
vl = __riscv_vsetvl_e32m2(n);
vfloat32m2x2_t vc =
__riscv_vlseg2e32_v_f32m2x2((const float*)complexFFTInput, vl);
vfloat32m2_t vr = __riscv_vget_f32m2(vc, 0);
vfloat32m2_t vi = __riscv_vget_f32m2(vc, 1);
vfloat32m2_t v = __riscv_vfmacc(__riscv_vfmul(vi, vi, vl), vr, vr, vl);
v = __riscv_vfmul(v, normFactSq, vl);
vfloat32m2_t a = __riscv_vfabs(v, vl);
vfloat32m2_t exp = __riscv_vfcvt_f(
__riscv_vsub(__riscv_vsra(__riscv_vreinterpret_i32m2(a), 23, vl), c127, vl),
vl);
vfloat32m2_t frac = __riscv_vreinterpret_f32m2(
__riscv_vor(__riscv_vand(__riscv_vreinterpret_i32m2(v), m2, vl), m1, vl));
vfloat32m2_t mant = c0;
mant = __riscv_vfmadd(mant, frac, c1, vl);
mant = __riscv_vfmadd(mant, frac, c2, vl);
#if LOG_POLY_DEGREE >= 4
mant = __riscv_vfmadd(mant, frac, c3, vl);
#if LOG_POLY_DEGREE >= 5
mant = __riscv_vfmadd(mant, frac, c4, vl);
#if LOG_POLY_DEGREE >= 6
mant = __riscv_vfmadd(mant, frac, c5, vl);
#endif
#endif
#endif
v = __riscv_vfmacc(exp, mant, __riscv_vfsub(frac, cf1, vl), vl);
v = __riscv_vfmul(v, volk_log2to10factor, vl);
__riscv_vse32(logPowerOutput, v, vl);
}
}
#endif /*LV_HAVE_RVVSEG*/
#endif /* INCLUDED_volk_32fc_s32f_power_spectrum_32f_a_H */