Skip to content

refactor(allocator): disable fixed size allocators on unsupported platforms #12272

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
graphite-app merged 1 commit into from
Jul 14, 2025
Merged

refactor(allocator): disable fixed size allocators on unsupported platforms #12272

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
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
16 changes: 1 addition & 15 deletions crates/oxc_allocator/src/fixed_size.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -7,14 +7,8 @@ use std::{

use crate::Allocator;

// Only 64-bit little-endian platforms are supported at present
const IS_SUPPORTED_PLATFORM: bool =
cfg!(all(target_pointer_width = "64", target_endian = "little"));

const TWO_GIB: usize = 1 << 31;
// `1 << 32`.
// We use `IS_SUPPORTED_PLATFORM as usize * 32` to avoid compilation failure on 32-bit platforms.
const FOUR_GIB: usize = 1 << (IS_SUPPORTED_PLATFORM as usize * 32);
const FOUR_GIB: usize = 1 << 32;

// What we ideally want is an allocation 2 GiB in size, aligned on 4 GiB.
// But system allocator on Mac OS refuses allocations with 4 GiB alignment.
Expand Down Expand Up @@ -61,15 +55,7 @@ pub struct FixedSizeAllocator {

impl FixedSizeAllocator {
/// Create a new [`FixedSizeAllocator`].
///
/// # Panics
/// Panics if not a 64-bit little-endian platform.
pub fn new() -> Self {
assert!(
IS_SUPPORTED_PLATFORM,
"Fixed size allocators are only supported on 64-bit little-endian platforms"
);

// Allocate block of memory.
// SAFETY: Layout does not have zero size.
let alloc_ptr = unsafe { System.alloc(ALLOC_LAYOUT) };
Expand Down
9 changes: 8 additions & 1 deletion crates/oxc_allocator/src/lib.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -21,6 +21,7 @@
//!
//! * `fixed_size` - Makes [`AllocatorPool`] create large fixed-size allocators, instead of
//! flexibly-sized ones.
//! Only supported on 64-bit little-endian platforms at present.
//! Usage of this feature is not advisable, and it will be removed as soon as we're able to.
//!
//! * `disable_fixed_size` - Disables `fixed_size` feature.
Expand All @@ -36,7 +37,13 @@ mod allocator_api2;
mod boxed;
mod clone_in;
mod convert;
#[cfg(all(feature = "fixed_size", not(feature = "disable_fixed_size")))]
// Fixed size allocators are only supported on 64-bit little-endian platforms at present
#[cfg(all(
feature = "fixed_size",
not(feature = "disable_fixed_size"),
target_pointer_width = "64",
target_endian = "little"
))]
mod fixed_size;
#[cfg(feature = "from_raw_parts")]
mod from_raw_parts;
Expand Down
14 changes: 12 additions & 2 deletions crates/oxc_allocator/src/pool.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -73,7 +73,12 @@ impl Drop for AllocatorGuard<'_> {
}
}

#[cfg(any(not(feature = "fixed_size"), feature = "disable_fixed_size"))]
#[cfg(not(all(
feature = "fixed_size",
not(feature = "disable_fixed_size"),
target_pointer_width = "64",
target_endian = "little"
)))]
mod wrapper {
use crate::Allocator;

Expand Down Expand Up @@ -105,7 +110,12 @@ mod wrapper {
}
}

#[cfg(all(feature = "fixed_size", not(feature = "disable_fixed_size")))]
#[cfg(all(
feature = "fixed_size",
not(feature = "disable_fixed_size"),
target_pointer_width = "64",
target_endian = "little"
))]
mod wrapper {
use crate::{
Allocator,
Expand Down
Loading