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Fixes setting of a Time to a float.

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Thomas Harte 2019-06-05 14:43:34 -04:00
parent 511d292e73
commit 08671ed69c
1 changed files with 31 additions and 17 deletions
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48
Storage/Storage.hpp
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@ -252,26 +252,40 @@ struct Time {
}
inline void install_float(float value) {
// Grab the float's native mantissa and exponent.
int exponent;
float mantissa = frexpf(value, &exponent);
float loaded_mantissa = ldexpf(mantissa, 24);
const float mantissa = frexpf(value, &exponent);
uint64_t result_length;
uint64_t result_clock_rate;
if(exponent < 0) {
int right_shift = -exponent;
result_length = (uint64_t)loaded_mantissa >> right_shift;
result_clock_rate = 1;
} else {
if(exponent <= 24) {
result_length = (uint64_t)loaded_mantissa;
result_clock_rate = 1 << (24 - exponent);
} else {
result_length = std::numeric_limits<uint64_t>::max();
result_clock_rate = 1;
}
// Turn the mantissa into an int, and adjust the exponent
// appropriately.
const uint64_t loaded_mantissa = uint64_t(ldexpf(mantissa, 24));
const auto relative_exponent = exponent - 24;
// If the mantissa is negative and its absolute value fits within a 64-bit integer,
// just load up.
if(relative_exponent <= 0 && relative_exponent > -64) {
install_result(loaded_mantissa, uint64_t(1 << -relative_exponent));
return;
}
// If the exponent is positive but doesn't cause loaded_mantissa to overflow,
// install with the natural encoding.
if(relative_exponent > 0 && relative_exponent < (64 - 24)) {
install_result(loaded_mantissa << relative_exponent, 1);
return;
}
// Otherwise, if this number is too large to store, store the maximum value.
if(relative_exponent > 0) {
install_result(std::numeric_limits<uint64_t>::max(), 1);
return;
}
// If the number is too small to store accurately, store 0.
if(relative_exponent < 0) {
install_result(0, 1);
return;
}
install_result(result_length, result_clock_rate);
}
};