Commit 1b62469ec93f78dbcebc90187eb9be795986d66f | zig

author	schtvn <schteven.codes@gmail.com> 2025-02-17 06:37:19-08:00
committer	GitHub <noreply@github.com> 2025-02-17 15:37:19+01:00
log	1b62469ec93f78dbcebc90187eb9be795986d66f
tree	b01e12ee0a9141e01024667a0a1d6ba63ce2354e
parent	d7b93c78769360c954a364613c1c1b382020da0a
signature	Signed by PGP key B5690EEEBB952194

Fix build failure in sbrk allocator, caused by #20511

2 files changed, 26 insertions(+), 7 deletions(-)

lib
- std
  - heap.zig
  - heap
    sbrk_allocator.zig

lib/std/heap.zig+1

...	...	@@ -989,6 +989,7 @@ test {
989	989	_ = GeneralPurposeAllocator;
990	990	_ = FixedBufferAllocator;
991	991	_ = ThreadSafeAllocator;
	992	_ = SbrkAllocator;
992	993	if (builtin.target.isWasm()) {
993	994	_ = WasmAllocator;
994	995	}

lib/std/heap/sbrk_allocator.zig+25-7

...	...	@@ -11,6 +11,7 @@ pub fn SbrkAllocator(comptime sbrk: *const fn (n: usize) usize) type {
11	11	pub const vtable: Allocator.VTable = .{
12	12	.alloc = alloc,
13	13	.resize = resize,
	14	.remap = remap,
14	15	.free = free,
15	16	};
16	17
...	...	@@ -39,14 +40,13 @@ pub fn SbrkAllocator(comptime sbrk: *const fn (n: usize) usize) type {
39	40
40	41	// TODO don't do the naive locking strategy
41	42	var lock: std.Thread.Mutex = .{};
42		fn alloc(ctx: anyopaque, len: usize, log2_align: u8, return_address: usize) ?[]u8 {
	43	fn alloc(ctx: anyopaque, len: usize, alignment: mem.Alignment, return_address: usize) ?[]u8 {
43	44	_ = ctx;
44	45	_ = return_address;
45	46	lock.lock();
46	47	defer lock.unlock();
47	48	// Make room for the freelist next pointer.
48		const alignment = @as(usize, 1) << @as(Allocator.Log2Align, @intCast(log2_align));
49		const actual_len = @max(len +\| @sizeOf(usize), alignment);
	49	const actual_len = @max(len +\| @sizeOf(usize), alignment.toByteUnits());
50	50	const slot_size = math.ceilPowerOfTwo(usize, actual_len) catch return null;
51	51	const class = math.log2(slot_size) - min_class;
52	52	if (class < size_class_count) {
...	...	@@ -82,7 +82,7 @@ pub fn SbrkAllocator(comptime sbrk: *const fn (n: usize) usize) type {
82	82	fn resize(
83	83	ctx: *anyopaque,
84	84	buf: []u8,
85		log2_buf_align: u8,
	85	alignment: mem.Alignment,
86	86	new_len: usize,
87	87	return_address: usize,
88	88	) bool {
...	...	@@ -92,7 +92,7 @@ pub fn SbrkAllocator(comptime sbrk: *const fn (n: usize) usize) type {
92	92	defer lock.unlock();
93	93	// We don't want to move anything from one size class to another, but we
94	94	// can recover bytes in between powers of two.
95		const buf_align = @as(usize, 1) << @as(Allocator.Log2Align, @intCast(log2_buf_align));
	95	const buf_align = alignment.toByteUnits();
96	96	const old_actual_len = @max(buf.len + @sizeOf(usize), buf_align);
97	97	const new_actual_len = @max(new_len +\| @sizeOf(usize), buf_align);
98	98	const old_small_slot_size = math.ceilPowerOfTwoAssert(usize, old_actual_len);
...	...	@@ -109,17 +109,27 @@ pub fn SbrkAllocator(comptime sbrk: *const fn (n: usize) usize) type {
109	109	}
110	110	}
111	111
	112	fn remap(
	113	context: *anyopaque,
	114	memory: []u8,
	115	alignment: mem.Alignment,
	116	new_len: usize,
	117	return_address: usize,
	118	) ?[*]u8 {
	119	return if (resize(context, memory, alignment, new_len, return_address)) memory.ptr else null;
	120	}
	121
112	122	fn free(
113	123	ctx: *anyopaque,
114	124	buf: []u8,
115		log2_buf_align: u8,
	125	alignment: mem.Alignment,
116	126	return_address: usize,
117	127	) void {
118	128	_ = ctx;
119	129	_ = return_address;
120	130	lock.lock();
121	131	defer lock.unlock();
122		const buf_align = @as(usize, 1) << @as(Allocator.Log2Align, @intCast(log2_buf_align));
	132	const buf_align = alignment.toByteUnits();
123	133	const actual_len = @max(buf.len + @sizeOf(usize), buf_align);
124	134	const slot_size = math.ceilPowerOfTwoAssert(usize, actual_len);
125	135	const class = math.log2(slot_size) - min_class;
...	...	@@ -158,3 +168,11 @@ pub fn SbrkAllocator(comptime sbrk: *const fn (n: usize) usize) type {
158	168	}
159	169	};
160	170	}
	171
	172	test SbrkAllocator {
	173	_ = SbrkAllocator(struct {
	174	fn sbrk(_: usize) usize {
	175	return 0;
	176	}
	177	}.sbrk);
	178	}