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fixed
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use parse::<primitives> instead of naive multiply accumulate

This commit is contained in:
Trevor Spiteri 2019-08-09 23:13:44 +02:00
parent 5459750f6d
commit 76a8e07f54
1 changed files with 19 additions and 24 deletions
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43
src/from_str.rs
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@ -318,11 +318,13 @@ macro_rules! impl_from_str_signed {
} else {
($one << (nbits - 1)) - 1
};
let mut acc = 0;
for c in int.chars() {
acc = acc * 10 + (c as u8 - b'0') as $DoubleBits;
err!(acc > max_abs_int, Overflow);
}
let mut acc = match int.parse::<$DoubleBits>() {
Ok(i) => {
err!(i > max_abs_int, Overflow);
i
}
Err(_) => err!(Overflow),
};
if whole_frac {
acc += 1;
err!(acc > max_abs_int, Overflow);
@ -367,11 +369,13 @@ macro_rules! impl_from_str_unsigned {
return Ok(0);
}
let max_abs_int = ($one << nbits) - 1;
let mut acc = 0;
for c in int.chars() {
acc = acc * 10 + (c as u8 - b'0') as $DoubleBits;
err!(acc > max_abs_int, Overflow);
}
let mut acc = match int.parse::<$DoubleBits>() {
Ok(i) => {
err!(i > max_abs_int, Overflow);
i
}
Err(_) => err!(Overflow),
};
if whole_frac {
acc += 1;
err!(acc > max_abs_int, Overflow);
@ -383,19 +387,10 @@ macro_rules! impl_from_str_unsigned {
if frac.is_empty() {
return Some(0);
}
let mut digits = $dec_frac_digits;
let mut acc = 0;
for c in frac.chars() {
if digits == 0 {
break;
}
digits -= 1;
acc = acc * 10 + (c as u8 - b'0') as $DoubleBits;
}
if digits > 0 {
acc *= ($one * 10).pow(digits);
}
$decode_frac(acc, <$Bits as SealedInt>::NBITS - nbits)
let end = cmp::min(frac.len(), $dec_frac_digits);
let rem = $dec_frac_digits - end;
let i = frac[..end].parse::<$DoubleBits>().unwrap() * ($one * 10).pow(rem as u32);
$decode_frac(i, <$Bits as SealedInt>::NBITS - nbits)
}
};
}
@ -654,7 +649,7 @@ mod tests {
fn check_dec27() {
let two_pow = 64f64.exp2();
let limit = 1_000_000_000_000_000_000_000_000_000;
for iter in 0..1_000_000 {
for iter in 0..200_000 {
for &i in &[
iter,
limit / 4 - 1 - iter,