src/fixed_point.cpp


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#include "fixed_point.h"
#include <cstdlib>
#include <cstdio>

fp_t fp_t::operator+(const fp_t& other) const {
    return {(std::int32_t)((std::uint32_t)raw + (std::uint32_t)other.raw)};
}

fp_t fp_t::operator-(const fp_t& other) const {
    return {(std::int32_t)((std::uint32_t)raw - (std::uint32_t)other.raw)};
}

fp_t fp_t::operator*(const fp_t& other) const {
    std::int32_t result;
    std::int64_t temp;
    temp = (std::int64_t)raw * (std::int64_t)other.raw;
    temp += fp_t::K;
    result = (std::int32_t)(temp >> fp_t::Q);
    return {result};
}

fp_t fp_t::operator/(const fp_t& other) const {
    if (other.raw == 0) {
        std::fprintf(stderr, "fp_t: division by zero\n");
        std::abort();
    }
    std::int64_t temp = (std::int64_t)raw << fp_t::Q;

    if ((temp >= 0 && other.raw >= 0) || (temp < 0 && other.raw < 0)) {
        temp += (other.raw / 2);
    } else {
        temp -= (other.raw / 2);
    }
    return {(std::int32_t)(temp / other.raw)};
}

bool fp_t::operator==(const fp_t& other) const {
    return raw == other.raw;
}