/* Audio Library for Teensy 3.X * Copyright (c) 2014, Paul Stoffregen, paul@pjrc.com * * Development of this audio library was funded by PJRC.COM, LLC by sales of * Teensy and Audio Adaptor boards. Please support PJRC's efforts to develop * open source software by purchasing Teensy or other PJRC products. * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice, development funding notice, and this permission * notice shall be included in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ #include #ifdef __cplusplus extern "C" const uint16_t sqrt_integer_guess_table[]; #else extern const uint16_t sqrt_integer_guess_table[]; #endif inline uint32_t sqrt_uint32(uint32_t in) __attribute__((always_inline,unused)); inline uint32_t sqrt_uint32(uint32_t in) { uint32_t n = sqrt_integer_guess_table[__builtin_clz(in)]; n = ((in / n) + n) / 2; n = ((in / n) + n) / 2; n = ((in / n) + n) / 2; return n; } inline uint32_t sqrt_uint32_approx(uint32_t in) __attribute__((always_inline,unused)); inline uint32_t sqrt_uint32_approx(uint32_t in) { uint32_t n = sqrt_integer_guess_table[__builtin_clz(in)]; n = ((in / n) + n) / 2; n = ((in / n) + n) / 2; return n; }