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use crate::digit_table::*;
use core::ptr;
#[cfg_attr(feature = "no-panic", inline)]
pub unsafe fn write_mantissa_long(mut output: u64, mut result: *mut u8) {
if (output >> 32) != 0 {
// One expensive 64-bit division.
let mut output2 = (output - 100_000_000 * (output / 100_000_000)) as u32;
output /= 100_000_000;
let c = output2 % 10_000;
output2 /= 10_000;
let d = output2 % 10_000;
let c0 = (c % 100) << 1;
let c1 = (c / 100) << 1;
let d0 = (d % 100) << 1;
let d1 = (d / 100) << 1;
ptr::copy_nonoverlapping(
DIGIT_TABLE.as_ptr().offset(c0 as isize),
result.offset(-2),
2,
);
ptr::copy_nonoverlapping(
DIGIT_TABLE.as_ptr().offset(c1 as isize),
result.offset(-4),
2,
);
ptr::copy_nonoverlapping(
DIGIT_TABLE.as_ptr().offset(d0 as isize),
result.offset(-6),
2,
);
ptr::copy_nonoverlapping(
DIGIT_TABLE.as_ptr().offset(d1 as isize),
result.offset(-8),
2,
);
result = result.offset(-8);
}
write_mantissa(output as u32, result);
}
#[cfg_attr(feature = "no-panic", inline)]
pub unsafe fn write_mantissa(mut output: u32, mut result: *mut u8) {
while output >= 10_000 {
let c = output - 10_000 * (output / 10_000);
output /= 10_000;
let c0 = (c % 100) << 1;
let c1 = (c / 100) << 1;
ptr::copy_nonoverlapping(
DIGIT_TABLE.as_ptr().offset(c0 as isize),
result.offset(-2),
2,
);
ptr::copy_nonoverlapping(
DIGIT_TABLE.as_ptr().offset(c1 as isize),
result.offset(-4),
2,
);
result = result.offset(-4);
}
if output >= 100 {
let c = (output % 100) << 1;
output /= 100;
ptr::copy_nonoverlapping(
DIGIT_TABLE.as_ptr().offset(c as isize),
result.offset(-2),
2,
);
result = result.offset(-2);
}
if output >= 10 {
let c = output << 1;
ptr::copy_nonoverlapping(
DIGIT_TABLE.as_ptr().offset(c as isize),
result.offset(-2),
2,
);
} else {
*result.offset(-1) = b'0' + output as u8;
}
}