Module types 

Core size constants, mirroring mimalloc v2.4.5 include/mimalloc/types.h.

Only constants verified against the oracle header live here. Anything still unverified is introduced in the milestone that implements it, alongside the G2 differential test that pins it (plan §4). In particular the full bin geometry (bin(size) mapping) lands in M2 pinned by mi_good_size equality.

Constants

BIN_FULL

The full-page queue index (MI_BIN_FULL = BIN_HUGE + 1).

BIN_HUGE

Index of the largest size bin (MI_BIN_HUGE = 73). Bins 1..=BIN_HUGE hold size-class page queues; BIN_FULL is the queue of full pages.

INTPTR_SIZE

Word size in bytes (MI_INTPTR_SIZE). We target 64-bit first.

LARGE_OBJ_SIZE_MAX

Largest object served from an in-segment large page (MI_LARGE_OBJ_SIZE_MAX = SEGMENT_SIZE/2 = 16 MiB). Above this a dedicated huge segment is used.

MAX_ALIGN_SIZE

Guaranteed natural alignment of every allocation (MI_MAX_ALIGN_SIZE = 16): mi_malloc(n) for n >= 16 returns 16-byte-aligned memory, matching max_align_t expectations of C callers.

MEDIUM_OBJ_SIZE_MAX

Largest binned object (MI_MEDIUM_OBJ_SIZE_MAX = 64 KiB) — G2-verified: the oracle’s mi_good_size switches to page-rounding above this.

MEDIUM_PAGE_SIZE

Medium page size in bytes.

MEDIUM_PAGE_SLICES

A medium page spans 8 slices (MI_MEDIUM_PAGE_SIZE = 512 KiB).

SEGMENT_SIZE

Segment size (MI_SEGMENT_SIZE = 32 MiB on 64-bit): the unit of OS/arena allocation, and the shift+mask that takes any block pointer to its segment (which is why segments are segment-size-aligned).

SEGMENT_SLICE_SIZE

Segment slice size (MI_SEGMENT_SLICE_SIZE = 64 KiB on 64-bit): the granularity v2 segments are carved in. A small page is one slice.

SLICES_PER_SEGMENT

Slices per segment (MI_SLICES_PER_SEGMENT = 512).

SMALL_OBJ_SIZE_MAX

Largest object served from a small page (MI_SMALL_OBJ_SIZE_MAX = 8 KiB).

SMALL_PAGE_SIZE

A small page is one slice (MI_SMALL_PAGE_SIZE = 64 KiB).

SMALL_SIZE_MAX

Maximum “small” allocation in bytes (MI_SMALL_SIZE_MAX = 1 KiB on 64-bit). mi_malloc_small / mi_zalloc_small require size <= SMALL_SIZE_MAX.

SMALL_WSIZE_MAX

Maximum “small” allocation in machine words (MI_SMALL_WSIZE_MAX = 128).

Functions

wsize_from_size

Size in machine words, rounded up (_mi_wsize_from_size).