SharedRegion

The threadsafe version of the Region allocator. Allocations and deallocations are lock-free based using core.atomic.cas.

shared

struct SharedRegion (

ParentAllocator = NullAllocator

uint minAlign = platformAlignment

Flag!"growDownwards" growDownwards = No.growDownwards

) {

ParentAllocator parent;

this(ubyte[] store);

this(size_t n);

size_t goodAllocSize(size_t n);

alias alignment = minAlign;

void[] allocate(size_t n);

bool deallocate(void[] b);

void[] alignedAllocate(size_t n, uint a);

Ternary owns(void[] b);

Ternary empty();

}

Constructors

this this(ubyte[] store)
this(size_t n): Constructs a region backed by a user-provided store. Assumes the memory was allocated with ParentAllocator (if different from `NullAllocator`).

Destructor

~this ~this(): If ParentAllocator is not `NullAllocator` and defines deallocate, the region defines a destructor that uses ParentAllocator.deallocate to free the memory chunk.

Members

Aliases

alignment alias alignment = minAlign: Alignment offered.

Functions

alignedAllocate void[] alignedAllocate(size_t n, uint a): Allocates n bytes of memory aligned at alignment a.
allocate void[] allocate(size_t n): Allocates n bytes of memory. The allocation is served by atomically incrementing a pointer which keeps track of the current used space.
deallocate bool deallocate(void[] b): Deallocates b. This works only if b was obtained as the last call to allocate; otherwise (i.e. another allocation has occurred since) it does nothing.
empty Ternary empty(): Returns Ternary.yes if no memory has been allocated in this region, Ternary.no otherwise. (Never returns Ternary.unknown.)
goodAllocSize size_t goodAllocSize(size_t n): Rounds the given size to a multiple of the alignment
owns Ternary owns(void[] b): Queries whether b has been allocated with this region.

Variables

parent ParentAllocator parent;: The parent allocator. Depending on whether ParentAllocator holds state or not, this is a member variable or an alias for ParentAllocator.instance.

Meta

Source

See Implementation

nxt region_allocator functions

structs