Skip to content

fix: use single precision for dtoa with f32 #2908

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 10 commits into from
Feb 8, 2025
Merged

fix: use single precision for dtoa with f32 #2908

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
10 commits
Select commit Hold shift + click to select a range
c7cb718
fix: use single precision for dtoa with f32
mattjohnsonpint Feb 6, 2025
75b8ab8
Update existing dtoa tests
mattjohnsonpint Feb 6, 2025
c50ecc1
re-create other text fixtures
mattjohnsonpint Feb 6, 2025
65ebc46
re-create test fixture on Linux
mattjohnsonpint Feb 6, 2025
91929af
.
mattjohnsonpint Feb 6, 2025
09013bc
.
mattjohnsonpint Feb 7, 2025
bf9a07b
.
mattjohnsonpint Feb 7, 2025
55db705
remove dtoa32/dtoa64
mattjohnsonpint Feb 7, 2025
043c480
handle integers as f64, error for non-numeric types
mattjohnsonpint Feb 7, 2025
9e8cba5
simplify
mattjohnsonpint Feb 7, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
58 changes: 41 additions & 17 deletions std/assembly/util/number.ts
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -474,7 +474,7 @@ export function itoa64(value: i64, radix: i32): String {
@lazy let _frc_minus: u64 = 0;

// @ts-ignore: decorator
@lazy let _frc_plus: u64 = 0;
@lazy let _frc_plus: u64 = 0;

// @ts-ignore: decorator
@lazy let _frc_pow: u64 = 0;
Expand Down Expand Up @@ -511,14 +511,14 @@ function umul64e(e1: i32, e2: i32): i32 {

// @ts-ignore: decorator
@inline
function normalizedBoundaries(f: u64, e: i32): void {
function normalizedBoundaries(f: u64, e: i32, isSingle: bool): void {
let frc = (f << 1) + 1;
let exp = e - 1;
let off = <i32>clz<u64>(frc);
frc <<= off;
exp -= off;

let m = 1 + i32(f == 0x0010000000000000);
let m = 1 + i32(f == (isSingle ? 0x00800000 : 0x0010000000000000));

_frc_plus = frc;
_frc_minus = ((f << m) - 1) << e - m - exp;
Expand Down Expand Up @@ -559,16 +559,26 @@ function getCachedPower(minExp: i32): void {

// @ts-ignore: decorator
@inline
function grisu2(value: f64, buffer: usize, sign: i32): i32 {
function grisu2(value: f64, buffer: usize, sign: i32, isSingle: bool): i32 {
let frc: u64;
let exp: i32;

// frexp routine
let uv = reinterpret<u64>(value);
let exp = i32((uv & 0x7FF0000000000000) >>> 52);
let sid = uv & 0x000FFFFFFFFFFFFF;
let frc = (u64(exp != 0) << 52) + sid;
exp = select<i32>(exp, 1, exp) - (0x3FF + 52);
if (isSingle) {
let uv = reinterpret<u32>(<f32>value);
exp = (uv & 0x7F800000) >>> 23;
let sid = uv & 0x007FFFFF;
frc = (u64(exp != 0) << 23) + sid;
exp = (exp || 1) - (0x7F + 23);
} else {
let uv = reinterpret<u64>(value);
exp = i32((uv & 0x7FF0000000000000) >>> 52);
let sid = uv & 0x000FFFFFFFFFFFFF;
frc = (u64(exp != 0) << 52) + sid;
exp = (exp || 1) - (0x3FF + 52);
}

normalizedBoundaries(frc, exp);
normalizedBoundaries(frc, exp, isSingle);
getCachedPower(_exp);

// normalize
Expand Down Expand Up @@ -716,28 +726,35 @@ function prettify(buffer: usize, length: i32, k: i32): i32 {
}
}

function dtoa_core(buffer: usize, value: f64): i32 {
function dtoa_core(buffer: usize, value: f64, isSingle: bool): i32 {
let sign = i32(value < 0);
if (sign) {
value = -value;
store<u16>(buffer, CharCode.MINUS);
}
// assert(value > 0 && value <= 1.7976931348623157e308);
let len = grisu2(value, buffer, sign);
// assert(value > 0 && value <= (isSingle ? f32.MAX_VALUE : f64.MAX_VALUE));
let len = grisu2(value, buffer, sign, isSingle);
len = prettify(buffer + (sign << 1), len - sign, _K);
return len + sign;
}

// @ts-ignore: decorator
@lazy @inline const dtoa_buf = memory.data(MAX_DOUBLE_LENGTH << 1);

export function dtoa(value: f64): String {
export function dtoa<T extends number>(value: T): String {
const isSingle = isFloat<T>() && sizeof<T>() == 4;
return dtoa_impl(value, isSingle);
}

// @ts-ignore: decorator
@inline
function dtoa_impl(value: f64, isSingle: bool): String {
if (value == 0) return "0.0";
if (!isFinite(value)) {
if (isNaN(value)) return "NaN";
return select<String>("-Infinity", "Infinity", value < 0);
}
let size = dtoa_core(dtoa_buf, value) << 1;
let size = dtoa_core(dtoa_buf, value, isSingle) << 1;
let result = changetype<String>(__new(size, idof<String>()));
memory.copy(changetype<usize>(result), dtoa_buf, size);
return result;
Expand Down Expand Up @@ -821,7 +838,14 @@ export function itoa_buffered<T extends number>(buffer: usize, value: T): u32 {
return sign + decimals;
}

export function dtoa_buffered(buffer: usize, value: f64): u32 {
export function dtoa_buffered<T extends number>(buffer: usize, value: T): u32 {
const isSingle = isFloat<T>() && sizeof<T>() == 4;
return dtoa_buffered_impl(buffer, value, isSingle);
}

// @ts-ignore: decorator
@inline
function dtoa_buffered_impl(buffer: usize, value: f64, isSingle: bool): u32 {
if (value == 0) {
store<u16>(buffer, CharCode._0);
store<u16>(buffer, CharCode.DOT, 2);
Expand All @@ -845,5 +869,5 @@ export function dtoa_buffered(buffer: usize, value: f64): u32 {
return 8 + u32(sign);
}
}
return dtoa_core(buffer, value);
return dtoa_core(buffer, value, isSingle);
}
Loading