Skip to content

Make page_size a runtime value #13

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
rdunnington merged 1 commit into from
Jul 31, 2025
Merged

Make page_size a runtime value #13

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
21 changes: 11 additions & 10 deletions stable_array.zig
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -28,16 +28,15 @@ pub fn StableArrayAligned(comptime T: type, comptime _alignment: u29) type {
pub const VariableSlice = [*]align(alignment) T;

pub const k_sizeof: usize = if (alignment > @sizeOf(T)) alignment else @sizeOf(T);
pub const page_size: usize = heap.pageSize();
pub const alignment = _alignment;

items: Slice,
capacity: usize,
max_virtual_alloc_bytes: usize,
page_size: usize,

pub fn getPageSize(self: *Self) usize {
_ = self;
return Self.page_size;
return self.page_size;
}

pub fn getAlignment(self: *Self) usize {
Expand All @@ -46,11 +45,13 @@ pub fn StableArrayAligned(comptime T: type, comptime _alignment: u29) type {
}

pub fn init(max_virtual_alloc_bytes: usize) Self {
const page_size = heap.pageSize();
assert(@mod(max_virtual_alloc_bytes, page_size) == 0); // max_virtual_alloc_bytes must be a multiple of page_size
return Self{
.items = &[_]T{},
.capacity = 0,
.max_virtual_alloc_bytes = max_virtual_alloc_bytes,
.page_size = page_size,
};
}

Expand Down Expand Up @@ -208,8 +209,8 @@ pub fn StableArrayAligned(comptime T: type, comptime _alignment: u29) type {
pub fn shrinkAndFree(self: *Self, new_len: usize) void {
assert(new_len <= self.items.len);

const new_capacity_bytes = calcBytesUsedForCapacity(new_len);
const current_capacity_bytes: usize = calcBytesUsedForCapacity(self.capacity);
const new_capacity_bytes = self.calcBytesUsedForCapacity(new_len);
const current_capacity_bytes: usize = self.calcBytesUsedForCapacity(self.capacity);

if (new_capacity_bytes < current_capacity_bytes) {
const bytes_to_free: usize = current_capacity_bytes - new_capacity_bytes;
Expand Down Expand Up @@ -268,8 +269,8 @@ pub fn StableArrayAligned(comptime T: type, comptime _alignment: u29) type {
}

pub fn ensureTotalCapacity(self: *Self, new_capacity: usize) AllocError!void {
const new_capacity_bytes = calcBytesUsedForCapacity(new_capacity);
const current_capacity_bytes: usize = calcBytesUsedForCapacity(self.capacity);
const new_capacity_bytes = self.calcBytesUsedForCapacity(new_capacity);
const current_capacity_bytes: usize = self.calcBytesUsedForCapacity(self.capacity);

if (current_capacity_bytes < new_capacity_bytes) {
if (self.capacity == 0) {
Expand Down Expand Up @@ -349,11 +350,11 @@ pub fn StableArrayAligned(comptime T: type, comptime _alignment: u29) type {
}

pub fn calcTotalUsedBytes(self: Self) usize {
return calcBytesUsedForCapacity(self.capacity);
return self.calcBytesUsedForCapacity(self.capacity);
}

fn calcBytesUsedForCapacity(capacity: usize) usize {
return mem.alignForward(usize, k_sizeof * capacity, page_size);
fn calcBytesUsedForCapacity(self: Self, capacity: usize) usize {
return mem.alignForward(usize, k_sizeof * capacity, self.page_size);
}
};
}
Expand Down
Loading