mirror of
https://github.com/fluencelabs/assemblyscript
synced 2025-04-25 15:12:12 +00:00
753 lines
22 KiB
TypeScript
753 lines
22 KiB
TypeScript
////////////// TLSF (Two-Level Segregate Fit) Memory Allocator ////////////////
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// based on https://github.com/mattconte/tlsf - BSD (see LICENSE file) //
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///////////////////////////////////////////////////////////////////////////////
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// Configuration
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const SL_INDEX_COUNT_LOG2: u32 = 5;
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// Internal constants
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const ALIGN_SIZE_LOG2: u32 = sizeof<usize>() == 8 ? 3 : 2;
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const ALIGN_SIZE: u32 = 1 << ALIGN_SIZE_LOG2;
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const FL_INDEX_MAX: u32 = sizeof<usize>() == 8 ? 32 : 30;
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const SL_INDEX_COUNT: u32 = 1 << SL_INDEX_COUNT_LOG2;
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const FL_INDEX_SHIFT: u32 = SL_INDEX_COUNT_LOG2 + ALIGN_SIZE_LOG2;
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const FL_INDEX_COUNT: u32 = FL_INDEX_MAX - FL_INDEX_SHIFT + 1;
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const SMALL_BLOCK_SIZE: u32 = 1 << FL_INDEX_SHIFT;
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/** Block header structure. */
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@explicit
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class BlockHeader {
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/////////////////////////////// Constants ///////////////////////////////////
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// One block header is 16 bytes in WASM32 and 32 bytes in WASM64.
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static readonly SIZE: usize = 4 * sizeof<usize>();
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// Since block sizes are always at least a multiple of 4, the two least
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// significant bits of the size field are used to store the block status.
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static readonly FREE_BIT: usize = 1 << 0;
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static readonly PREV_FREE_BIT: usize = 1 << 1;
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// The size of the block header exposed to used blocks is the size field.
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// The prev_phys_block field is stored *inside* the previous free block.
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static readonly OVERHEAD: usize = sizeof<usize>();
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// User data starts directly after the size field in a used block.
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static readonly DATA_OFFSET: usize = sizeof<usize>() + sizeof<usize>();
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// A free block must be large enough to store its header minus the size of
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// the prev_phys_block field, and no larger than the number of addressable
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// bits for FL_INDEX.
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static readonly BLOCK_SIZE_MIN: usize = BlockHeader.SIZE - sizeof<usize>();
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static readonly BLOCK_SIZE_MAX: usize = <usize>1 << FL_INDEX_MAX;
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///////////////////////////////// Fields ////////////////////////////////////
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/**
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* Points to the previous physical block. Only valid if the previous block is
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* free. Actually stored at the end of the previous block.
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*/
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prev_phys_block: BlockHeader;
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/**
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* The size of this block, excluding the block header. The two least
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* significant bits are used to store the block status.
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*/
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tagged_size: usize;
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/** Next free block. Only valid if the block is free. */
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next_free: BlockHeader;
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/** Previous free block. Only valid if the block is free. */
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prev_free: BlockHeader;
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///////////////////////////////// Methods ///////////////////////////////////
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/** Gets the size of this block, excluding the block header. */
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get size(): usize {
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const tags = BlockHeader.FREE_BIT | BlockHeader.PREV_FREE_BIT;
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return this.tagged_size & ~tags;
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}
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/** Sets the size of this block, retaining tagged bits. */
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set size(size: usize) {
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const tags = BlockHeader.FREE_BIT | BlockHeader.PREV_FREE_BIT;
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this.tagged_size = size | (this.tagged_size & tags);
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}
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/** Tests if this is the last block. */
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get isLast(): bool {
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return this.size == 0;
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}
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/** Tests if this block's status is 'free'. */
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get isFree(): bool {
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return (this.tagged_size & BlockHeader.FREE_BIT) != 0;
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}
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/** Tags this block as 'free'. Careful: Does not update adjacent blocks. */
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tagFree(): void {
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this.tagged_size |= BlockHeader.FREE_BIT;
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}
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/** Tags this block as 'used'. Careful: Does not update adjacent blocks. */
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tagUsed(): void {
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this.tagged_size &= ~BlockHeader.FREE_BIT;
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}
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/** Tests if the previous block is free. */
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get isPrevFree(): bool {
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return (this.tagged_size & BlockHeader.PREV_FREE_BIT) != 0;
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}
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/** Tags this block as 'prev is free'. Does not update adjacent blocks. */
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tagPrevFree(): void {
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this.tagged_size |= BlockHeader.PREV_FREE_BIT;
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}
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/** Tags this block as 'prev is used'. Does not update adjacent blocks. */
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tagPrevUsed(): void {
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this.tagged_size &= ~BlockHeader.PREV_FREE_BIT;
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}
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/** Gets the block header matching the specified data pointer. */
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static fromDataPtr(ptr: usize): BlockHeader {
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return changetype<BlockHeader>(ptr - BlockHeader.DATA_OFFSET);
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}
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/** Returns the address of this block's data. */
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toDataPtr(): usize {
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return changetype<usize>(this) + BlockHeader.DATA_OFFSET;
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}
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/** Gets the next block after this one using the specified size. */
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static fromOffset(ptr: usize, size: usize): BlockHeader {
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return changetype<BlockHeader>(ptr + <usize>size);
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}
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/** Gets the previous block. */
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get prev(): BlockHeader {
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assert(this.isPrevFree,
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"previous block must be free"
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);
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return this.prev_phys_block;
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}
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/** Gets the next block. */
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get next(): BlockHeader {
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assert(!this.isLast,
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"last block has no next block"
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);
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return BlockHeader.fromOffset(
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this.toDataPtr(),
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this.size - BlockHeader.OVERHEAD
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);
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}
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/**
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* Links this block with its physical next block and returns the next block.
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*/
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linkNext(): BlockHeader {
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var next = this.next;
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next.prev_phys_block = this;
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return next;
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}
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/** Marks this block as being 'free'. */
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markAsFree(): void {
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var next = this.linkNext(); // Link the block to the next block, first.
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next.tagPrevFree();
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this.tagFree();
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}
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/** Marks this block as being 'used'. */
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markAsUsed(): void {
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var next = this.next;
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next.tagPrevUsed();
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this.tagUsed();
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}
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/** Tests if this block can be splitted. */
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canSplit(size: usize): bool {
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return this.size >= BlockHeader.SIZE + size;
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}
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/** Splits a block into two, the second of which is free. */
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split(size: usize): BlockHeader {
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// Calculate the amount of space left in the remaining block.
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var remain = BlockHeader.fromOffset(
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this.toDataPtr(),
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size - BlockHeader.OVERHEAD
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);
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var remain_size = this.size - (size + BlockHeader.OVERHEAD);
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assert(remain.toDataPtr() == align_ptr(remain.toDataPtr(), ALIGN_SIZE),
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"remaining block not aligned properly"
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);
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remain.size = remain_size;
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assert(remain.size >= BlockHeader.BLOCK_SIZE_MIN,
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"block split with invalid size"
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);
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this.size = size;
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remain.markAsFree();
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return remain;
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}
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/** Absorb a free block's storage into this (adjacent previous) free block. */
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absorb(block: BlockHeader): void {
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assert(!this.isLast,
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"previous block can't be last"
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);
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// Leaves tags untouched
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this.tagged_size += block.size + BlockHeader.OVERHEAD;
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this.linkNext();
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}
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}
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/** The TLSF control structure. */
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@explicit
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class Control extends BlockHeader { // Empty lists point here, indicating free
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// The control structure uses 3188 bytes in WASM32.
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static readonly SIZE: usize = (
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BlockHeader.SIZE
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+ (1 + FL_INDEX_COUNT) * sizeof<u32>()
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+ FL_INDEX_COUNT * SL_INDEX_COUNT * sizeof<usize>()
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);
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///////////////////////////////// Fields ////////////////////////////////////
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/** First level free list bitmap. */
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fl_bitmap: u32;
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/**
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* Gets the second level free list bitmap for the specified index.
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* Equivalent to `sl_bitmap[fl_index]`.
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*/
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sl_bitmap(fl_index: u32): u32 {
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const offset = BlockHeader.SIZE + sizeof<u32>();
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return load<u32>(
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changetype<usize>(this)
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+ offset
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+ fl_index * sizeof<u32>()
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);
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}
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/**
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* Sets the second level free list bitmap for the specified index.
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* Equivalent to `sl_bitmap[fl_index] = sl_map`.
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*/
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sl_bitmap_set(fl_index: u32, sl_map: u32): void {
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const offset = BlockHeader.SIZE + sizeof<u32>();
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return store<u32>(
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changetype<usize>(this)
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+ offset
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+ fl_index * sizeof<u32>(),
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sl_map
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);
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}
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/**
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* Gets the head of the free list for the specified indexes.
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* Equivalent to `blocks[fl_index][sl_index]`.
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*/
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blocks(fli: u32, sli: u32): BlockHeader {
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const offset = BlockHeader.SIZE + (1 + FL_INDEX_COUNT) * sizeof<u32>();
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return load<BlockHeader>(
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changetype<usize>(this)
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+ offset
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+ (fli * SL_INDEX_COUNT + sli) * sizeof<usize>()
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);
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}
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/**
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* Sets the head of the free list for the specified indexes.
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* Equivalent to `blocks[fl_index][sl_index] = block`.
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*/
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blocks_set(fl_index: u32, sl_index: u32, block: BlockHeader): void {
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const offset = BlockHeader.SIZE + (1 + FL_INDEX_COUNT) * sizeof<u32>();
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return store<BlockHeader>(
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changetype<usize>(this)
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+ offset
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+ (fl_index * SL_INDEX_COUNT + sl_index) * sizeof<usize>(),
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block
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);
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}
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///////////////////////////////// Methods ///////////////////////////////////
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/** Removes a given block from the free list. */
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removeBlock(block: BlockHeader): void {
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mapping_insert(block.size);
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this.removeFreeBlock(block, fl_out, sl_out);
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}
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/** Inserts a given block into the free list. */
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insertBlock(block: BlockHeader): void {
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mapping_insert(block.size);
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this.insertFreeBlock(block, fl_out, sl_out);
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}
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/** Inserts a free block into the free block list. */
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insertFreeBlock(block: BlockHeader, fl: i32, sl: i32): void {
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var current = this.blocks(fl, sl);
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assert(current,
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"free list cannot have a null entry"
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);
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assert(block,
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"cannot insert a null entry into the free list"
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);
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block.next_free = current;
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block.prev_free = this;
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current.prev_free = block;
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assert(block.toDataPtr() == align_ptr(block.toDataPtr(), ALIGN_SIZE),
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"block not aligned properly"
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);
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// Insert the new block at the head of the list, and mark the first-
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// and second-level bitmaps appropriately.
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this.blocks_set(fl, sl, block);
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this.fl_bitmap |= (1 << fl);
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this.sl_bitmap_set(fl, this.sl_bitmap(fl) | (1 << sl))
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}
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/** Removes a free block from the free list.*/
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removeFreeBlock(block: BlockHeader, fl: i32, sl: i32): void {
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var prev = block.prev_free;
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var next = block.next_free;
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assert(prev,
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"prev_free field cannot be null"
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);
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assert(next,
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"next_free field cannot be null"
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);
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next.prev_free = prev;
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prev.next_free = next;
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if (this.blocks(fl, sl) == block) {
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this.blocks_set(fl, sl, next);
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if (next == this) {
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this.sl_bitmap_set(fl, this.sl_bitmap(fl) & ~(1 << sl));
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if (!this.sl_bitmap(fl)) {
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this.fl_bitmap &= ~(1 << fl);
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}
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}
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}
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}
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/** Merges a just-freed block with an adjacent previous free block. */
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mergePrevBlock(block: BlockHeader): BlockHeader {
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if (block.isPrevFree) {
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var prev = block.prev;
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assert(prev,
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"prev physical block can't be null"
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);
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assert(prev.isFree,
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"prev block is not free though marked as such"
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);
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this.removeBlock(prev);
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prev.absorb(block);
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block = prev;
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}
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return block;
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}
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/** Merges a just-freed block with an adjacent free block. */
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mergeNextBlock(block: BlockHeader): BlockHeader {
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var next = block.next;
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assert(next,
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"next physical block can't be null"
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);
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if (next.isFree) {
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assert(!block.isLast,
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"previous block can't be last"
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);
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this.removeBlock(next);
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block.absorb(next);
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}
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return block;
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}
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/**
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* Trims any trailing block space off the end of a block and returns it to
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* the pool. */
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trimFreeBlock(block: BlockHeader, size: usize): void {
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assert(block.isFree,
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"block must be free"
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);
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if (block.canSplit(size)) {
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var remaining_block = block.split(size);
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block.linkNext();
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remaining_block.tagPrevFree();
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this.insertBlock(remaining_block);
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}
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}
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/**
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* Trims any trailing block space off the end of a used block and returns it
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* to the pool.
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*/
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trimUsedBlock(block: BlockHeader, size: usize): void {
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assert(!block.isFree,
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"block must be used"
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);
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if (block.canSplit(size)) {
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// If the next block is free, we must coalesce.
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var remaining_block = block.split(size);
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remaining_block.tagPrevUsed();
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remaining_block = this.mergeNextBlock(remaining_block);
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this.insertBlock(remaining_block);
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}
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}
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trimFreeBlockLeading(block: BlockHeader, size: usize): BlockHeader {
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var remaining_block = block;
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if (block.canSplit(size)) {
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remaining_block = block.split(size - BlockHeader.OVERHEAD);
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remaining_block.tagPrevFree();
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block.linkNext();
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this.insertBlock(block);
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}
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return remaining_block;
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}
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locateFreeBlock(size: usize): BlockHeader {
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var block = changetype<BlockHeader>(0);
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if (size) {
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mapping_search(size);
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if (fl_out < FL_INDEX_MAX) {
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block = find_suitable_block(this, fl_out, sl_out);
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}
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}
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if (block) {
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assert(block.size >= size);
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this.removeFreeBlock(block, fl_out, sl_out);
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}
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return block;
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}
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prepareUsedBlock(block: BlockHeader, size: usize): usize {
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var ptr: usize = 0;
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if (block) {
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assert(size,
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"size must be non-zero"
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);
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this.trimFreeBlock(block, size);
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block.markAsUsed();
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ptr = block.toDataPtr();
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}
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return ptr;
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}
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/**
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* Creates a TLSF control structure at the specified memory address,
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* providing the specified number of bytes.
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*/
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static create(mem: usize, bytes: usize): Control {
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if ((mem % ALIGN_SIZE) != 0)
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throw new RangeError("Memory must be aligned");
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// Clear structure and point all empty lists at the null block.
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var control = changetype<Control>(mem);
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control.next_free = control;
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control.prev_free = control;
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control.fl_bitmap = 0;
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for (var i = 0; i < FL_INDEX_COUNT; ++i) {
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control.sl_bitmap_set(i, 0);
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for (var j = 0; j < SL_INDEX_COUNT; ++j) {
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control.blocks_set(i, j, control);
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}
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}
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// Add the initial memory pool
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control.addPool(mem + Control.SIZE, bytes - Control.SIZE);
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return control;
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}
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/** Adds a pool of free memory. */
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addPool(mem: usize, bytes: usize): void {
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// Overhead of the TLSF structures in a given memory block, equal
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// to the overhead of the free block and the sentinel block.
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const pool_overhead = BlockHeader.OVERHEAD * 2;
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var pool_bytes = align_down(bytes - pool_overhead, ALIGN_SIZE);
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if ((mem % ALIGN_SIZE) != 0)
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throw new RangeError("Memory must be aligned");
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if (pool_bytes < BlockHeader.BLOCK_SIZE_MIN ||
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pool_bytes > BlockHeader.BLOCK_SIZE_MAX)
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throw new RangeError("Memory size must be between min and max");
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// Create the main free block. Offset the start of the block slightly
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// so that the prev_phys_block field falls outside of the pool -
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// it will never be used.
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var block = BlockHeader.fromOffset(mem, -BlockHeader.OVERHEAD);
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block.size = pool_bytes;
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block.tagFree();
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block.tagPrevUsed();
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this.insertBlock(block);
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// Split the block to create a zero-size sentinel block.
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var next = block.linkNext();
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next.size = 0;
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next.tagUsed();
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next.tagPrevFree();
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}
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}
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// Alignment helpers
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function align_up(x: usize, align: usize): usize {
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assert(!(align & (align - 1)),
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"must align to a power of two"
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);
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return (x + (align - 1)) & ~(align - 1);
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}
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function align_down(x: usize, align: usize): usize {
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assert(!(align & (align - 1)),
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"must align to a power of two"
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);
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return x - (x & (align - 1));
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}
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function align_ptr(ptr: usize, align: usize): usize {
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var aligned = (ptr + (align - 1)) & ~(align - 1);
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assert(!(align & (align - 1)),
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"must align to a power of two"
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);
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return aligned;
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}
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/**
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* Adjusts an allocation size to be aligned to word size, and no smaller than
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* the internal minimum.
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*/
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function adjust_request_size(size: usize, align: usize): usize {
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var adjust: usize = 0;
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if (size && size < BlockHeader.BLOCK_SIZE_MAX) {
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var aligned = align_up(size, align);
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adjust = max(aligned, BlockHeader.BLOCK_SIZE_MIN);
|
|
}
|
|
return adjust;
|
|
}
|
|
|
|
// TLSF utility functions. In most cases, these are direct translations of the
|
|
// documentation found in the white paper.
|
|
|
|
function ffs<T>(word: i32): i32 {
|
|
return word ? <i32>ctz(word) : -1;
|
|
}
|
|
|
|
function fls<T>(word: T): i32 {
|
|
return (<i32>sizeof<T>() << 3) - 1 - <i32>clz(word);
|
|
}
|
|
|
|
var fl_out: i32, sl_out: i32;
|
|
|
|
function mapping_insert(size: usize): void {
|
|
var fl: i32, sl: i32;
|
|
if (size < SMALL_BLOCK_SIZE) { // Store small blocks in first list.
|
|
fl = 0;
|
|
sl = <i32>size / (SMALL_BLOCK_SIZE / SL_INDEX_COUNT);
|
|
} else {
|
|
fl = fls<usize>(size);
|
|
sl = (<i32>size >> (fl - SL_INDEX_COUNT_LOG2)) ^ 1 << SL_INDEX_COUNT_LOG2;
|
|
fl -= FL_INDEX_SHIFT - 1;
|
|
}
|
|
fl_out = fl;
|
|
sl_out = sl;
|
|
}
|
|
|
|
function mapping_search(size: usize): void {
|
|
if (size >= SMALL_BLOCK_SIZE)
|
|
size += (1 << (fls<usize>(size) - SL_INDEX_COUNT_LOG2)) - 1;
|
|
mapping_insert(size);
|
|
}
|
|
|
|
function find_suitable_block(control: Control, fl: i32, sl: i32): BlockHeader {
|
|
// Search for a block in the list associated with the given fl/sl index
|
|
var sl_map = control.sl_bitmap(fl) & (<u32>~0 << sl);
|
|
if (!sl_map) {
|
|
// If no block exists, search in the next largest first-level list
|
|
var fl_map = control.fl_bitmap & (<u32>~0 << (fl + 1));
|
|
if (!fl_map)
|
|
return changetype<BlockHeader>(0); // Memory pool has been exhausted
|
|
fl = ctz<u32>(fl_map); // ^= ffs<u32>(fl_map) with fl_map != 0
|
|
fl_out = fl;
|
|
sl_map = control.sl_bitmap(fl);
|
|
}
|
|
assert(sl_map,
|
|
"second level bitmap is null"
|
|
);
|
|
sl = ctz<u32>(sl_map); // ^= ffs<u32>(sl_map) with sl_map != 0
|
|
sl_out = sl;
|
|
return control.blocks(fl, sl); // First block in the free list
|
|
}
|
|
|
|
// Exported interface
|
|
|
|
var TLSF: Control;
|
|
|
|
/** Requests more memory from the host environment. */
|
|
function request_memory(size: usize): void {
|
|
if (size & 0xffff) // Round size up to a full page
|
|
size = (size | 0xffff) + 1;
|
|
// At least double the memory for efficiency
|
|
var prev_pages = grow_memory(max<u32>(current_memory(), <u32>size >> 16));
|
|
if (prev_pages < 0)
|
|
unreachable(); // Out of host memory. This is bad.
|
|
var next_pages = current_memory();
|
|
TLSF.addPool(<usize>prev_pages << 16, <usize>(next_pages - prev_pages) << 16);
|
|
}
|
|
|
|
/** Allocates a chunk of memory of the given size and returns its address. */
|
|
export function allocate_memory(size: usize): usize {
|
|
if (!TLSF) // Initialize when actually used so it DCEs just fine otherwise
|
|
TLSF = Control.create(HEAP_BASE, (current_memory() << 16) - HEAP_BASE);
|
|
var control = changetype<Control>(TLSF);
|
|
var adjust = adjust_request_size(size, ALIGN_SIZE);
|
|
var block = control.locateFreeBlock(adjust);
|
|
if (!block && size > 0) {
|
|
request_memory(adjust);
|
|
block = control.locateFreeBlock(adjust);
|
|
}
|
|
return control.prepareUsedBlock(block, adjust);
|
|
}
|
|
|
|
/** Disposes a chunk of memory by its pointer. */
|
|
export function free_memory(ptr: usize): void {
|
|
if (TLSF && ptr) {
|
|
var control = changetype<Control>(TLSF);
|
|
var block = BlockHeader.fromDataPtr(ptr);
|
|
assert(!block.isFree,
|
|
"block already marked as free"
|
|
);
|
|
block.markAsFree();
|
|
block = control.mergePrevBlock(block);
|
|
block = control.mergeNextBlock(block);
|
|
control.insertBlock(block);
|
|
}
|
|
}
|
|
|
|
// Extra debugging
|
|
|
|
assert(sizeof<u32>() << 3 >= SL_INDEX_COUNT,
|
|
"SL_INDEX_COUNT must be <= number of bits in sl_bitmap's storage type"
|
|
);
|
|
assert(ALIGN_SIZE == SMALL_BLOCK_SIZE / SL_INDEX_COUNT,
|
|
"invalid alignment"
|
|
);
|
|
assert(test_ffs_fls() == 0,
|
|
"ffs/fls are not working properly"
|
|
);
|
|
|
|
function test_ffs_fls(): i32 {
|
|
var rv = 0;
|
|
rv += (ffs<u32>(0) == -1) ? 0 : 0x1;
|
|
rv += (fls<u32>(0) == -1) ? 0 : 0x2;
|
|
rv += (ffs<u32>(1) == 0) ? 0 : 0x4;
|
|
rv += (fls<u32>(1) == 0) ? 0 : 0x8;
|
|
rv += (ffs<u32>(0x80000000) == 31) ? 0 : 0x10;
|
|
rv += (ffs<u32>(0x80008000) == 15) ? 0 : 0x20;
|
|
rv += (fls<u32>(0x80000008) == 31) ? 0 : 0x40;
|
|
rv += (fls<u32>(0x7FFFFFFF) == 30) ? 0 : 0x80;
|
|
rv += (fls<u64>(0x80000000) == 31) ? 0 : 0x100;
|
|
rv += (fls<u64>(0x100000000) == 32) ? 0 : 0x200;
|
|
rv += (fls<u64>(0xffffffffffffffff) == 63) ? 0 : 0x400;
|
|
return rv;
|
|
}
|
|
|
|
function check(): i32 {
|
|
if (!TLSF)
|
|
TLSF = Control.create(HEAP_BASE, (current_memory() << 16) - HEAP_BASE);
|
|
var control = changetype<Control>(TLSF);
|
|
var status = 0;
|
|
for (var i = 0; i < FL_INDEX_COUNT; ++i) {
|
|
for (var j = 0; j < SL_INDEX_COUNT; ++j) {
|
|
var fl_map = control.fl_bitmap & (1 << i);
|
|
var sl_list = control.sl_bitmap(i);
|
|
var sl_map = sl_list & (1 << j);
|
|
var block = control.blocks(i, j);
|
|
if (!fl_map) {
|
|
if (!assert(!sl_map,
|
|
"second-level map must be null")
|
|
) --status;
|
|
}
|
|
if (!sl_map) {
|
|
if (!assert(block == control,
|
|
"block list must be null")
|
|
) --status;
|
|
} else {
|
|
if (!assert(sl_list,
|
|
"no free blocks in second-level map")
|
|
) --status;
|
|
if (!assert(block != control,
|
|
"block should not be null")
|
|
) --status;
|
|
while (block != control) {
|
|
if (!assert(block.isFree,
|
|
"block should be free")
|
|
) --status;
|
|
if (!assert(!block.isPrevFree,
|
|
"blocks should have coalesced")
|
|
) --status;
|
|
if (!assert(!block.next.isFree,
|
|
"blocks should have coalesced")
|
|
) --status;
|
|
if (!assert(block.next.isPrevFree,
|
|
"block should be free")
|
|
) --status;
|
|
if (!assert(block.size >= BlockHeader.BLOCK_SIZE_MIN,
|
|
"block < minimum size")
|
|
) --status;
|
|
mapping_insert(block.size);
|
|
if (!assert(fl_out == i && sl_out == j,
|
|
"block size indexed in wrong list")
|
|
) --status;
|
|
block = block.next_free;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
return status;
|
|
}
|
|
|
|
var integrity_prev_status: i32;
|
|
var integrity_status: i32;
|
|
|
|
function integrity_walker(ptr: usize, size: usize, used: bool): void {
|
|
var block = BlockHeader.fromDataPtr(ptr);
|
|
var this_prev_status = block.isPrevFree;
|
|
var this_status = block.isFree;
|
|
var this_block_size = block.size;
|
|
|
|
var status = 0;
|
|
if (!assert(integrity_prev_status == this_prev_status,
|
|
"prev status incorrect")
|
|
) --status;
|
|
if (!assert(size == this_block_size,
|
|
"block size incorrect")
|
|
) --status;
|
|
integrity_prev_status = this_status;
|
|
integrity_status += status;
|
|
}
|
|
|
|
function check_pool(pool: usize): i32 {
|
|
if (pool < 0x10000) { // first pool
|
|
pool = changetype<usize>(TLSF) + Control.SIZE;
|
|
}
|
|
// inlined walk_bool with static integrity_walker
|
|
integrity_prev_status = integrity_status = 0;
|
|
var block = BlockHeader.fromOffset(pool, -BlockHeader.OVERHEAD);
|
|
while (block && !block.isLast) {
|
|
integrity_walker(
|
|
block.toDataPtr(),
|
|
block.size,
|
|
!block.isFree
|
|
);
|
|
block = block.next;
|
|
}
|
|
return integrity_status;
|
|
}
|
|
|
|
// export { check, check_pool }; // Uncomment to enable in tests/index.js
|