portapack-mayhem/firmware/common/utility.cpp

137 lines
3.3 KiB
C++

/*
* Copyright (C) 2014 Jared Boone, ShareBrained Technology, Inc.
*
* This file is part of PortaPack.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street,
* Boston, MA 02110-1301, USA.
*/
#include <ch.h>
#include "utility.hpp"
#include <cstdint>
#include <cmath>
#if 0
uint32_t gcd(const uint32_t u, const uint32_t v) {
/* From http://en.wikipedia.org/wiki/Binary_GCD_algorithm */
if( u == v ) {
return u;
}
if( u == 0 ) {
return v;
}
if( v == 0 ) {
return u;
}
if( ~u & 1 ) {
if( v & 1 ) {
return gcd(u >> 1, v);
} else {
return gcd(u >> 1, v >> 1) << 1;
}
}
if( ~v & 1 ) {
return gcd(u, v >> 1);
}
if( u > v ) {
return gcd((u - v) >> 1, v);
}
return gcd((v - u) >> 1, u);
}
#endif
float complex16_mag_squared_to_dbv_norm(const float c16_mag_squared) {
constexpr float mag2_max = -32768.0f * -32768.0f + -32768.0f * -32768.0f;
constexpr float mag2_log10_max = std::log10(mag2_max);
constexpr float mag2_to_db_factor = 20.0f / 2.0f;
return (std::log10(c16_mag_squared) - mag2_log10_max) * mag2_to_db_factor;
}
/* GCD implementation derived from recursive implementation at
* http://en.wikipedia.org/wiki/Binary_GCD_algorithm
*/
static constexpr uint32_t gcd_top(const uint32_t u, const uint32_t v);
static constexpr uint32_t gcd_larger(const uint32_t u, const uint32_t v) {
return (u > v) ? gcd_top((u - v) >> 1, v) : gcd_top((v - u) >> 1, u);
}
static constexpr uint32_t gcd_u_odd_v_even(const uint32_t u, const uint32_t v) {
return (~v & 1) ? gcd_top(u, v >> 1) : gcd_larger(u, v);
}
static constexpr uint32_t gcd_v_odd(const uint32_t u, const uint32_t v) {
return (v & 1)
? gcd_top(u >> 1, v)
: (gcd_top(u >> 1, v >> 1) << 1);
}
static constexpr uint32_t gcd_u_even(const uint32_t u, const uint32_t v) {
return (~u & 1)
? gcd_v_odd(u, v)
: gcd_u_odd_v_even(u, v)
;
}
static constexpr uint32_t gcd_v_zero(const uint32_t u, const uint32_t v) {
return (v == 0) ? u : gcd_u_even(u, v);
}
static constexpr uint32_t gcd_u_zero(const uint32_t u, const uint32_t v) {
return (u == 0) ? v : gcd_v_zero(u, v);
}
static constexpr uint32_t gcd_uv_equal(const uint32_t u, const uint32_t v) {
return (u == v) ? u : gcd_u_zero(u, v);
}
static constexpr uint32_t gcd_top(const uint32_t u, const uint32_t v) {
return gcd_uv_equal(u, v);
}
uint32_t gcd(const uint32_t u, const uint32_t v) {
return gcd_top(u, v);
}
/* Memory management, overriding toolchain new, which uses malloc */
/* TODO: Move to something like "memory.cpp"! Not utility.cpp. */
void* operator new(size_t size) {
return chHeapAlloc(0x0, size);
}
void* operator new[](size_t size) {
return chHeapAlloc(0x0, size);
}
void operator delete(void* p) noexcept {
chHeapFree(p);
}
void operator delete[](void* p) noexcept {
chHeapFree(p);
}