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gen/scalable_malloc.c Libc-391 /dev/null
--- Libc/Libc-391/gen/scalable_malloc.c
+++ /dev/null
@@ -1,3882 +0,0 @@
-/*
- * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
- *
- * @APPLE_LICENSE_HEADER_START@
- * 
- * This file contains Original Code and/or Modifications of Original Code
- * as defined in and that are subject to the Apple Public Source License
- * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
- * file.
- * 
- * The Original Code and all software distributed under the License are
- * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
- * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
- * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
- * Please see the License for the specific language governing rights and
- * limitations under the License.
- * 
- * @APPLE_LICENSE_HEADER_END@
- */
-
-/* Author: Bertrand Serlet, August 1999 */
-
-#include "scalable_malloc.h"
-
-#include <pthread_internals.h>
-
-#include <unistd.h>
-#include <libc.h>
-#include <mach/vm_statistics.h>
-#include <mach/mach_init.h>
-
-/*********************	DEFINITIONS	************************/
-
-#define DEBUG_MALLOC	0	// set to one to debug malloc itself
-
-#define DEBUG_CLIENT	0	// set to one to help debug a nasty memory smasher
-
-#if DEBUG_MALLOC
-#warning DEBUG_MALLOC ENABLED
-# define INLINE
-# define ALWAYSINLINE
-# define CHECK_LOCKED(szone, fun)						\
-do {										\
-    if (__is_threaded && TRY_LOCK(szone->lock)) {				\
-	malloc_printf("*** lock was not set %p in %s\n", szone->lock, fun);	\
-    }										\
-} while (0)
-#else
-# define INLINE	__inline__
-# define ALWAYSINLINE __attribute__((always_inline))
-# define CHECK_LOCKED(szone, fun)	{}
-#endif
-
-/*
- * Access to global variables is slow, so optimise our handling of vm_page_size
- * and vm_page_shift.
- */
-#define _vm_page_size 	vm_page_size	/* to get to the originals */
-#define _vm_page_shift	vm_page_shift
-#define vm_page_size	4096		/* our normal working sizes */
-#define vm_page_shift	12
-
-typedef unsigned short msize_t; // a size in multiples of SHIFT_SMALL_QUANTUM or SHIFT_TINY_QUANTUM
-
-/*
- * Note that in the LP64 case, this is 24 bytes, necessitating the 32-byte tiny grain size.
- */
-typedef struct {
-    uintptr_t	checksum;
-    void	*previous;
-    void	*next;
-} free_list_t;
-
-typedef struct {
-    uintptr_t 	address_and_num_pages;
-    // this type represents both an address and a number of pages
-    // the low bits are the number of pages; the high bits are the address
-    // note that the exact number of bits used for depends on the page size
-    // also, this cannot represent pointers larger than 1 << (vm_page_shift * 2)
-} compact_range_t;
-
-typedef unsigned char	grain_t;
-
-#define CHECK_REGIONS			(1 << 31)
-
-#ifdef __LP64__
-# define CHECKSUM_MAGIC			0xdeadbeef0badc0de
-#else
-# define CHECKSUM_MAGIC			0x357B
-#endif
-
-#define MAX_RECORDER_BUFFER	256
-
-/*********************	DEFINITIONS for tiny	************************/
-
-/*
- * Memory in the Tiny range is allocated from regions (heaps) pointed to by the szone's tiny_regions
- * pointer.
- *
- * Each region is laid out as a heap (1MB in 32-bit mode, 2MB in 64-bit mode), followed by a header
- * block.  The header block is arranged:
- *
- * 0x0
- * 	header bits
- * 0x2000
- *	0xffffffff pad word
- * 0x2004
- *	in-use bits
- * 0x4004
- *	pad word (not written)
- *
- * Each bitfield comprises NUM_TINY_BLOCKS bits, and refers to the corresponding TINY_QUANTUM block
- * within the heap.
- *
- * The bitfields are used to encode the state of memory within the heap.  The header bit indicates
- * that the corresponding quantum is the first quantum in a block (either in use or free).  The
- * in-use bit is set for the header if the block has been handed out (allocated).  If the header
- * bit is not set, the in-use bit is invalid.
- *
- * The szone maintains an array of 32 freelists, each of which is used to hold free objects
- * of the corresponding quantum size.
- *
- * A free block is laid out as:
- *
- * Offset (32-bit mode)	(64-bit mode)
- * 0x0			0x0
- *					checksum
- * 0x4			0x08
- *					previous
- * 0x8			0x10
- *					next
- * 0xc			0x18
- *					size (in quantum counts)
- * end - 2		end - 2
- *					size (in quantum counts)
- * end			end
- *
- * All fields are pointer-sized, except for the size which is an unsigned short.
- *
- */
-
-#ifdef __LP64__
-# define SHIFT_TINY_QUANTUM			5	// Required to fit free_list_t
-#else
-# define SHIFT_TINY_QUANTUM			4	// Required for AltiVec
-#endif
-#define	TINY_QUANTUM				(1 << SHIFT_TINY_QUANTUM)
-
-#define FOLLOWING_TINY_PTR(ptr,msize)		(((unsigned char *)(ptr)) + ((msize) << SHIFT_TINY_QUANTUM))
-
-#define NUM_TINY_SLOTS				32	// number of slots for free-lists
-
-#define SHIFT_NUM_TINY_BLOCKS			16
-#define NUM_TINY_BLOCKS				(1 << SHIFT_NUM_TINY_BLOCKS)
-#define TINY_BLOCKS_ALIGN			(SHIFT_NUM_TINY_BLOCKS + SHIFT_TINY_QUANTUM)
-
-/*
- * Enough room for the data, followed by the bit arrays (2-bits per block) plus 2 words of padding
- * as our bitmap operators overflow, plus rounding to the nearest page.
- */
-#define TINY_REGION_SIZE	((NUM_TINY_BLOCKS * TINY_QUANTUM + (NUM_TINY_BLOCKS >> 2) + 8 + vm_page_size - 1) & ~ (vm_page_size - 1))
-
-/*
- * Obtain the size of a free tiny block (in msize_t units).
- */
-#ifdef __LP64__
-# define TINY_FREE_SIZE(ptr)			(((msize_t *)(ptr))[14])
-#else
-# define TINY_FREE_SIZE(ptr)			(((msize_t *)(ptr))[6])
-#endif
-/*
- * The size is also kept at the very end of a free block.
- */
-#define TINY_PREVIOUS_MSIZE(ptr)		((msize_t *)(ptr))[-1]
-
-/*
- * Beginning and end pointers for a region's heap.
- */
-#define TINY_REGION_ADDRESS(region)		((void *)(region))
-#define TINY_REGION_END(region)			(TINY_REGION_ADDRESS(region) + (1 << TINY_BLOCKS_ALIGN))
-
-/*
- * Locate the heap base for a pointer known to be within a tiny region.
- */
-#define TINY_REGION_FOR_PTR(_p)			((void *)((uintptr_t)(_p) & ~((1 << TINY_BLOCKS_ALIGN) - 1)))
-
-/*
- * Convert between byte and msize units.
- */
-#define TINY_BYTES_FOR_MSIZE(_m)		((_m) << SHIFT_TINY_QUANTUM)
-#define TINY_MSIZE_FOR_BYTES(_b)		((_b) >> SHIFT_TINY_QUANTUM)
-
-/*
- * Locate the block header for a pointer known to be within a tiny region.
- */
-#define TINY_BLOCK_HEADER_FOR_PTR(_p)		((void *)(((((uintptr_t)(_p)) >> TINY_BLOCKS_ALIGN) + 1) << TINY_BLOCKS_ALIGN))
-
-/*
- * Locate the inuse map for a given block header pointer.
- */  
-#define TINY_INUSE_FOR_HEADER(_h)		((void *)((uintptr_t)(_h) + (NUM_TINY_BLOCKS >> 3) + 4))
-
-/*
- * Compute the bitmap index for a pointer known to be within a tiny region.
- */
-#define TINY_INDEX_FOR_PTR(_p) 			(((uintptr_t)(_p) >> SHIFT_TINY_QUANTUM) & (NUM_TINY_BLOCKS - 1))
-
-typedef void *tiny_region_t;
-
-#define INITIAL_NUM_TINY_REGIONS		24	// must be even for szone to be aligned
-
-#define TINY_CACHE	1	// This governs a last-free cache of 1 that bypasses the free-list
-
-#if ! TINY_CACHE
-#warning TINY_CACHE turned off
-#endif
-
-/*********************	DEFINITIONS for small	************************/
-
-/*
- * Memory in the Small range is allocated from regions (heaps) pointed to by the szone's small_regions
- * pointer.
- *
- * Each region is laid out as a heap (8MB in 32-bit and 64-bit mode), followed by the metadata array.
- * The array is arranged as an array of shorts, one for each SMALL_QUANTUM in the heap.
- *
- * The MSB of each short is set for the first quantum in a free block.  The low 15 bits encode the
- * block size (in SMALL_QUANTUM units), or are zero if the quantum is not the first in a block.
- *
- * The szone maintains an array of 32 freelists, each of which is used to hold free objects
- * of the corresponding quantum size.
- *
- * A free block is laid out as:
- *
- * Offset (32-bit mode)	(64-bit mode)
- * 0x0			0x0
- *					checksum
- * 0x4			0x08
- *					previous
- * 0x8			0x10
- *					next
- * 0xc			0x18
- *					size (in quantum counts)
- * end - 2		end - 2
- *					size (in quantum counts)
- * end			end
- *
- * All fields are pointer-sized, except for the size which is an unsigned short.
- *
- */
-
-#define SMALL_IS_FREE				(1 << 15)
-
-#define	SHIFT_SMALL_QUANTUM			(SHIFT_TINY_QUANTUM + 5)	// 9
-#define	SMALL_QUANTUM				(1 << SHIFT_SMALL_QUANTUM) // 512 bytes
-
-#define FOLLOWING_SMALL_PTR(ptr,msize)		(((unsigned char *)(ptr)) + ((msize) << SHIFT_SMALL_QUANTUM))
-
-#define NUM_SMALL_SLOTS				32	// number of slots for free-lists
-
-/*
- * We can only represent up to 1<<15 for msize; but we choose to stay even below that to avoid the
- * convention msize=0 => msize = (1<<15)
- */
-#define SHIFT_NUM_SMALL_BLOCKS			14
-#define NUM_SMALL_BLOCKS			(1 << SHIFT_NUM_SMALL_BLOCKS)
-#define SMALL_BLOCKS_ALIGN			(SHIFT_NUM_SMALL_BLOCKS + SHIFT_SMALL_QUANTUM) // 23
-#define SMALL_REGION_SIZE			(NUM_SMALL_BLOCKS * SMALL_QUANTUM + NUM_SMALL_BLOCKS * 2)	// data + meta data
-
-#define SMALL_PREVIOUS_MSIZE(ptr)		((msize_t *)(ptr))[-1]
-
-/*
- * Convert between byte and msize units.
- */
-#define SMALL_BYTES_FOR_MSIZE(_m)		((_m) << SHIFT_SMALL_QUANTUM)
-#define SMALL_MSIZE_FOR_BYTES(_b)		((_b) >> SHIFT_SMALL_QUANTUM)
-
-
-#define SMALL_REGION_ADDRESS(region)		((unsigned char *)region)
-#define SMALL_REGION_END(region)		(SMALL_REGION_ADDRESS(region) + (1 << SMALL_BLOCKS_ALIGN))
-
-/*
- * Locate the heap base for a pointer known to be within a small region.
- */
-#define SMALL_REGION_FOR_PTR(_p)		((void *)((uintptr_t)(_p) & ~((1 << SMALL_BLOCKS_ALIGN) - 1)))
-
-/*
- * Locate the metadata base for a pointer known to be within a small region.
- */
-#define SMALL_META_HEADER_FOR_PTR(_p)		((msize_t *)(((((uintptr_t)(_p)) >> SMALL_BLOCKS_ALIGN) + 1) << SMALL_BLOCKS_ALIGN))
-
-/*
- * Compute the metadata index for a pointer known to be within a small region.
- */
-#define SMALL_META_INDEX_FOR_PTR(_p)	       (((uintptr_t)(_p) >> SHIFT_SMALL_QUANTUM) & (NUM_SMALL_BLOCKS - 1))
-
-/*
- * Find the metadata word for a pointer known to be within a small region.
- */
-#define SMALL_METADATA_FOR_PTR(_p)		(SMALL_META_HEADER_FOR_PTR(_p) + SMALL_META_INDEX_FOR_PTR(_p))
-
-/*
- * Determine whether a pointer known to be within a small region points to memory which is free.
- */
-#define SMALL_PTR_IS_FREE(_p)			(*SMALL_METADATA_FOR_PTR(_p) & SMALL_IS_FREE)
-
-/*
- * Extract the msize value for a pointer known to be within a small region.
- */
-#define SMALL_PTR_SIZE(_p)			(*SMALL_METADATA_FOR_PTR(_p) & ~SMALL_IS_FREE)
-
-typedef void * small_region_t;
-
-#define INITIAL_NUM_SMALL_REGIONS		6	// must be even for szone to be aligned
-
-#define PROTECT_SMALL				0	// Should be 0: 1 is too slow for normal use
-
-#define SMALL_CACHE	1
-#if !SMALL_CACHE
-#warning SMALL_CACHE turned off
-#endif
-
-/*********************	DEFINITIONS for large	************************/
-
-#define LARGE_THRESHOLD			(15 * 1024) // at or above this use "large"
-
-#if (LARGE_THRESHOLD > NUM_SMALL_SLOTS * SMALL_QUANTUM)
-#error LARGE_THRESHOLD should always be less than NUM_SMALL_SLOTS * SMALL_QUANTUM
-#endif
-
-#define VM_COPY_THRESHOLD		(40 * 1024)
-    // When all memory is touched after a copy, vm_copy() is always a lose
-    // But if the memory is only read, vm_copy() wins over memmove() at 3 or 4 pages (on a G3/300MHz)
-    // This must be larger than LARGE_THRESHOLD
-
-/*
- * Given a large_entry, return the address of the allocated block.
- */
-#define LARGE_ENTRY_ADDRESS(entry)					\
-    (void *)(((entry).address_and_num_pages >> vm_page_shift) << vm_page_shift)
-
-/*
- * Given a large entry, return the number of pages or bytes in the allocated block.
- */
-#define LARGE_ENTRY_NUM_PAGES(entry)					\
-    ((entry).address_and_num_pages & (vm_page_size - 1))
-#define LARGE_ENTRY_SIZE(entry)						\
-    (LARGE_ENTRY_NUM_PAGES(entry) << vm_page_shift)
-
-/*
- * Compare a pointer with a large entry.
- */
-#define LARGE_ENTRY_MATCHES(entry,ptr)					\
-    ((((entry).address_and_num_pages - (uintptr_t)(ptr)) >> vm_page_shift) == 0)
-
-#define LARGE_ENTRY_IS_EMPTY(entry)	(((entry).address_and_num_pages) == 0)
-
-typedef compact_range_t large_entry_t;
-
-/*********************	DEFINITIONS for huge	************************/
-
-typedef vm_range_t huge_entry_t;
-
-/*********************	zone itself	************************/
-
-typedef struct {
-    malloc_zone_t	basic_zone;
-    pthread_lock_t	lock;
-    unsigned		debug_flags;
-    void		*log_address;
-
-    /* Regions for tiny objects */
-    unsigned		num_tiny_regions;
-    tiny_region_t	*tiny_regions;
-    void		*last_tiny_free; // low SHIFT_TINY_QUANTUM indicate the msize
-    unsigned		tiny_bitmap; // cache of the 32 free lists
-    free_list_t		*tiny_free_list[NUM_TINY_SLOTS]; // 31 free lists for 1*TINY_QUANTUM to 31*TINY_QUANTUM plus 1 for larger than 32*SMALL_QUANTUM
-    size_t		tiny_bytes_free_at_end; // the last free region in the last block is treated as a big block in use that is not accounted for
-    unsigned		num_tiny_objects;
-    size_t		num_bytes_in_tiny_objects;
-
-    /* Regions for small objects */
-    unsigned		num_small_regions;
-    small_region_t	*small_regions;
-    void		*last_small_free; // low SHIFT_SMALL_QUANTUM indicate the msize
-    unsigned		small_bitmap; // cache of the free list
-    free_list_t		*small_free_list[NUM_SMALL_SLOTS];
-    size_t		small_bytes_free_at_end; // the last free region in the last block is treated as a big block in use that is not accounted for
-    unsigned		num_small_objects;
-    size_t		num_bytes_in_small_objects;
-
-    /* large objects: vm_page_shift <= log2(size) < 2 *vm_page_shift */
-    unsigned		num_large_objects_in_use;
-    unsigned		num_large_entries;
-    large_entry_t	*large_entries; // hashed by location; null entries don't count
-    size_t		num_bytes_in_large_objects;
-    
-    /* huge objects: log2(size) >= 2 *vm_page_shift */
-    unsigned		num_huge_entries;
-    huge_entry_t	*huge_entries;
-    size_t		num_bytes_in_huge_objects;
-
-    /* Initial region list */
-    tiny_region_t	initial_tiny_regions[INITIAL_NUM_TINY_REGIONS];
-    small_region_t	initial_small_regions[INITIAL_NUM_SMALL_REGIONS];
-} szone_t;
-
-#if DEBUG_MALLOC || DEBUG_CLIENT
-static void		szone_sleep(void);
-#endif
-static void		szone_error(szone_t *szone, const char *msg, const void *ptr);
-static void		protect(szone_t *szone, void *address, size_t size, unsigned protection, unsigned debug_flags);
-static void		*allocate_pages(szone_t *szone, size_t size, unsigned char align, unsigned debug_flags, int vm_page_label);
-static void		deallocate_pages(szone_t *szone, void *addr, size_t size, unsigned debug_flags);
-static kern_return_t	_szone_default_reader(task_t task, vm_address_t address, vm_size_t size, void **ptr);
-
-static INLINE void	free_list_checksum(szone_t *szone, free_list_t *ptr, const char *msg) ALWAYSINLINE;
-static INLINE void	free_list_set_checksum(szone_t *szone, free_list_t *ptr) ALWAYSINLINE;
-static unsigned		free_list_count(const free_list_t *ptr);
-
-static INLINE msize_t	get_tiny_meta_header(const void *ptr, boolean_t *is_free) ALWAYSINLINE;
-static INLINE void	set_tiny_meta_header_in_use(const void *ptr, msize_t msize) ALWAYSINLINE;
-static INLINE void	set_tiny_meta_header_middle(const void *ptr) ALWAYSINLINE;
-static INLINE void	set_tiny_meta_header_free(const void *ptr, msize_t msize) ALWAYSINLINE;
-static INLINE boolean_t	tiny_meta_header_is_free(const void *ptr) ALWAYSINLINE;
-static INLINE void	*tiny_previous_preceding_free(void *ptr, msize_t *prev_msize) ALWAYSINLINE;
-static INLINE void	tiny_free_list_add_ptr(szone_t *szone, void *ptr, msize_t msize) ALWAYSINLINE;
-static INLINE void	tiny_free_list_remove_ptr(szone_t *szone, void *ptr, msize_t msize) ALWAYSINLINE;
-static INLINE tiny_region_t *tiny_region_for_ptr_no_lock(szone_t *szone, const void *ptr) ALWAYSINLINE;
-static INLINE void	tiny_free_no_lock(szone_t *szone, tiny_region_t *region, void *ptr, msize_t msize) ALWAYSINLINE;
-static void		*tiny_malloc_from_region_no_lock(szone_t *szone, msize_t msize);
-static INLINE boolean_t	try_realloc_tiny_in_place(szone_t *szone, void *ptr, size_t old_size, size_t new_size) ALWAYSINLINE;
-static boolean_t	tiny_check_region(szone_t *szone, tiny_region_t *region);
-static kern_return_t	tiny_in_use_enumerator(task_t task, void *context, unsigned type_mask, vm_address_t region_address, unsigned short num_regions, size_t tiny_bytes_free_at_end, memory_reader_t reader, vm_range_recorder_t recorder);
-static INLINE void	*tiny_malloc_from_free_list(szone_t *szone, msize_t msize) ALWAYSINLINE;
-static INLINE void	*tiny_malloc_should_clear(szone_t *szone, msize_t msize, boolean_t cleared_requested) ALWAYSINLINE;
-static INLINE void	free_tiny(szone_t *szone, void *ptr, tiny_region_t *tiny_region) ALWAYSINLINE;
-static void		print_tiny_free_list(szone_t *szone);
-static void		print_tiny_region(boolean_t verbose, tiny_region_t region, size_t bytes_at_end);
-static boolean_t	tiny_free_list_check(szone_t *szone, grain_t slot);
-
-static INLINE void	small_meta_header_set_is_free(msize_t *meta_headers, unsigned index, msize_t msize) ALWAYSINLINE;
-static INLINE void	small_meta_header_set_in_use(msize_t *meta_headers, msize_t index, msize_t msize) ALWAYSINLINE;
-static INLINE void	small_meta_header_set_middle(msize_t *meta_headers, msize_t index) ALWAYSINLINE;
-static void		small_free_list_add_ptr(szone_t *szone, void *ptr, msize_t msize);
-static void		small_free_list_remove_ptr(szone_t *szone, void *ptr, msize_t msize);
-static INLINE small_region_t *small_region_for_ptr_no_lock(szone_t *szone, const void *ptr) ALWAYSINLINE;
-static INLINE void	small_free_no_lock(szone_t *szone, small_region_t *region, void *ptr, msize_t msize) ALWAYSINLINE;
-static void		*small_malloc_from_region_no_lock(szone_t *szone, msize_t msize);
-static INLINE boolean_t	try_realloc_small_in_place(szone_t *szone, void *ptr, size_t old_size, size_t new_size) ALWAYSINLINE;
-static boolean_t	szone_check_small_region(szone_t *szone, small_region_t *region);
-static kern_return_t	small_in_use_enumerator(task_t task, void *context, unsigned type_mask, vm_address_t region_address, unsigned short num_regions, size_t small_bytes_free_at_end, memory_reader_t reader, vm_range_recorder_t recorder);
-static INLINE void	*small_malloc_from_free_list(szone_t *szone, msize_t msize) ALWAYSINLINE;
-static INLINE void	*small_malloc_should_clear(szone_t *szone, msize_t msize, boolean_t cleared_requested) ALWAYSINLINE;
-static INLINE void	*small_malloc_cleared_no_lock(szone_t *szone, msize_t msize) ALWAYSINLINE;
-static INLINE void	free_small(szone_t *szone, void *ptr, small_region_t *small_region) ALWAYSINLINE;
-static void		print_small_free_list(szone_t *szone);
-static void		print_small_region(szone_t *szone, boolean_t verbose, small_region_t *region, size_t bytes_at_end);
-static boolean_t	small_free_list_check(szone_t *szone, grain_t grain);
-
-#if DEBUG_MALLOC
-static void		large_debug_print(szone_t *szone);
-#endif
-static large_entry_t	*large_entry_for_pointer_no_lock(szone_t *szone, const void *ptr);
-static void		large_entry_insert_no_lock(szone_t *szone, large_entry_t range);
-static INLINE void	large_entries_rehash_after_entry_no_lock(szone_t *szone, large_entry_t *entry) ALWAYSINLINE;
-static INLINE large_entry_t *large_entries_alloc_no_lock(szone_t *szone, unsigned num) ALWAYSINLINE;
-static void		large_entries_free_no_lock(szone_t *szone, large_entry_t *entries, unsigned num, vm_range_t *range_to_deallocate);
-static void		large_entries_grow_no_lock(szone_t *szone, vm_range_t *range_to_deallocate);
-static vm_range_t	large_free_no_lock(szone_t *szone, large_entry_t *entry);
-static kern_return_t	large_in_use_enumerator(task_t task, void *context, unsigned type_mask, vm_address_t large_entries_address, unsigned num_entries, memory_reader_t reader, vm_range_recorder_t recorder);
-static huge_entry_t	*huge_entry_for_pointer_no_lock(szone_t *szone, const void *ptr);
-static boolean_t	huge_entry_append(szone_t *szone, huge_entry_t huge);
-static kern_return_t	huge_in_use_enumerator(task_t task, void *context, unsigned type_mask, vm_address_t huge_entries_address, unsigned num_entries, memory_reader_t reader, vm_range_recorder_t recorder);
-static void		*large_and_huge_malloc(szone_t *szone, unsigned num_pages);
-static INLINE void	free_large_or_huge(szone_t *szone, void *ptr) ALWAYSINLINE;
-static INLINE int	try_realloc_large_or_huge_in_place(szone_t *szone, void *ptr, size_t old_size, size_t new_size) ALWAYSINLINE;
-
-static void		szone_free(szone_t *szone, void *ptr);
-static INLINE void	*szone_malloc_should_clear(szone_t *szone, size_t size, boolean_t cleared_requested) ALWAYSINLINE;
-static void		*szone_malloc(szone_t *szone, size_t size);
-static void		*szone_calloc(szone_t *szone, size_t num_items, size_t size);
-static void		*szone_valloc(szone_t *szone, size_t size);
-static size_t		szone_size(szone_t *szone, const void *ptr);
-static void		*szone_realloc(szone_t *szone, void *ptr, size_t new_size);
-static unsigned		szone_batch_malloc(szone_t *szone, size_t size, void **results, unsigned count);
-static void		szone_batch_free(szone_t *szone, void **to_be_freed, unsigned count);
-static void		szone_destroy(szone_t *szone);
-static size_t		szone_good_size(szone_t *szone, size_t size);
-
-static boolean_t	szone_check_all(szone_t *szone, const char *function);
-static boolean_t	szone_check(szone_t *szone);
-static kern_return_t	szone_ptr_in_use_enumerator(task_t task, void *context, unsigned type_mask, vm_address_t zone_address, memory_reader_t reader, vm_range_recorder_t recorder);
-static void		szone_print(szone_t *szone, boolean_t verbose);
-static void		szone_log(malloc_zone_t *zone, void *log_address);
-static void		szone_force_lock(szone_t *szone);
-static void		szone_force_unlock(szone_t *szone);
-
-static void		szone_statistics(szone_t *szone, malloc_statistics_t *stats);
-
-static void		*frozen_malloc(szone_t *zone, size_t new_size);
-static void		*frozen_calloc(szone_t *zone, size_t num_items, size_t size);
-static void		*frozen_valloc(szone_t *zone, size_t new_size);
-static void		*frozen_realloc(szone_t *zone, void *ptr, size_t new_size);
-static void		frozen_free(szone_t *zone, void *ptr);
-static void		frozen_destroy(szone_t *zone);
-
-#if DEBUG_MALLOC
-# define LOG(szone,ptr)							\
-    (szone->log_address && (((uintptr_t)szone->log_address == -1) || (szone->log_address == (void *)(ptr))))
-#else
-# define LOG(szone,ptr)		0
-#endif
-
-#define SZONE_LOCK(szone)						\
-	do {								\
-	    LOCK(szone->lock);						\
-	} while (0)
-
-#define SZONE_UNLOCK(szone)						\
-	do {								\
-	    UNLOCK(szone->lock);					\
-	} while (0)
-
-#define LOCK_AND_NOTE_LOCKED(szone,locked)				\
-do {									\
-    CHECK(szone, __PRETTY_FUNCTION__);					\
-    locked = 1; SZONE_LOCK(szone);					\
-} while (0)
-
-#if DEBUG_MALLOC || DEBUG_CLIENT
-# define CHECK(szone,fun)						\
-    if ((szone)->debug_flags & CHECK_REGIONS) szone_check_all(szone, fun)
-#else
-# define CHECK(szone,fun)	do {} while (0)
-#endif
-
-/*********************	VERY LOW LEVEL UTILITIES  ************************/
-
-#if DEBUG_MALLOC || DEBUG_CLIENT
-static void
-szone_sleep(void)
-{
-
-    if (getenv("MallocErrorSleep")) {
-	malloc_printf("*** sleeping to help debug\n");
-	sleep(3600); // to help debug
-    }
-}
-#endif
-
-static void
-szone_error(szone_t *szone, const char *msg, const void *ptr)
-{
-
-    if (szone) SZONE_UNLOCK(szone);
-    if (ptr) {
-	malloc_printf("*** error for object %p: %s\n", ptr, msg);
-    } else {
-	malloc_printf("*** error: %s\n", msg);
-    }
-    malloc_printf("*** set a breakpoint in szone_error to debug\n");
-#if DEBUG_MALLOC
-    szone_print(szone, 1);
-    szone_sleep();
-#endif
-#if DEBUG_CLIENT
-    szone_sleep();
-#endif
-}
-
-static void
-protect(szone_t *szone, void *address, size_t size, unsigned protection, unsigned debug_flags)
-{
-    kern_return_t	err;
-
-    if (!(debug_flags & SCALABLE_MALLOC_DONT_PROTECT_PRELUDE)) {
-	err = vm_protect(mach_task_self(), (vm_address_t)(uintptr_t)address - vm_page_size, vm_page_size, 0, protection);
-	if (err) {
-	    malloc_printf("*** can't protect(%p) region for prelude guard page at %p\n",
-	      protection,address - (1 << vm_page_shift));
-	}
-    }
-    if (!(debug_flags & SCALABLE_MALLOC_DONT_PROTECT_POSTLUDE)) {
-	err = vm_protect(mach_task_self(), (vm_address_t)(uintptr_t)address + size, vm_page_size, 0, protection);
-	if (err) {
-	    malloc_printf("*** can't protect(%p) region for postlude guard page at %p\n",
-	      protection, address + size);
-	}
-    }
-}
-
-static void *
-allocate_pages(szone_t *szone, size_t size, unsigned char align, unsigned debug_flags, int vm_page_label)
-{
-    // align specifies a desired alignment (as a log) or 0 if no alignment requested
-    kern_return_t	err;
-    vm_address_t	vm_addr;
-    uintptr_t		addr, aligned_address;
-    boolean_t		add_guard_pages = debug_flags & SCALABLE_MALLOC_ADD_GUARD_PAGES;
-    size_t		allocation_size = round_page(size);
-    size_t		delta;
-    
-    if (align) add_guard_pages = 0; // too cumbersome to deal with that
-    if (!allocation_size) allocation_size = 1 << vm_page_shift;
-    if (add_guard_pages) allocation_size += 2 * (1 << vm_page_shift);
-    if (align) allocation_size += (size_t)1 << align;
-    err = vm_allocate(mach_task_self(), &vm_addr, allocation_size, vm_page_label | 1);
-    if (err) {
-	malloc_printf("*** vm_allocate(size=%lld) failed (error code=%d)\n", (long long)size, err);
-	szone_error(szone, "can't allocate region", NULL);
-	return NULL;
-    }
-    addr = (uintptr_t)vm_addr;
-    if (align) {
-	aligned_address = (addr + ((uintptr_t)1 << align) - 1) & ~ (((uintptr_t)1 << align) - 1);
-	if (aligned_address != addr) {
-	    delta = aligned_address - addr;
-	    err = vm_deallocate(mach_task_self(), (vm_address_t)addr, delta);
-	    if (err)
-		malloc_printf("*** freeing unaligned header failed with %d\n", err);
-	    addr = aligned_address;
-	    allocation_size -= delta;
-	}
-	if (allocation_size > size) {
-	    err = vm_deallocate(mach_task_self(), (vm_address_t)addr + size, allocation_size - size);
-	    if (err)
-		malloc_printf("*** freeing unaligned footer failed with %d\n", err);
-	}
-    }
-    if (add_guard_pages) {
-	addr += (uintptr_t)1 << vm_page_shift;
-	protect(szone, (void *)addr, size, 0, debug_flags);
-    }
-    return (void *)addr;
-}
-
-static void
-deallocate_pages(szone_t *szone, void *addr, size_t size, unsigned debug_flags)
-{
-    kern_return_t	err;
-    boolean_t		add_guard_pages = debug_flags & SCALABLE_MALLOC_ADD_GUARD_PAGES;
-
-    if (add_guard_pages) {
-	addr -= 1 << vm_page_shift;
-	size += 2 * (1 << vm_page_shift);
-    }
-    err = vm_deallocate(mach_task_self(), (vm_address_t)addr, size);
-    if (err && szone)
-	szone_error(szone, "Can't deallocate_pages region", addr);
-}
-
-static kern_return_t
-_szone_default_reader(task_t task, vm_address_t address, vm_size_t size, void **ptr)
-{
-    *ptr = (void *)address;
-    return 0;
-}
-
-static INLINE void
-free_list_checksum(szone_t *szone, free_list_t *ptr, const char *msg)
-{
-    // We always checksum, as testing whether to do it (based on szone->debug_flags) is as fast as
-    // doing it
-    // XXX not necessarily true for LP64 case
-    if (ptr->checksum != (((uintptr_t)ptr->previous) ^ ((uintptr_t)ptr->next) ^ CHECKSUM_MAGIC)) {
-#if DEBUG_MALLOC
-	malloc_printf("*** incorrect checksum: %s\n", msg);
-#endif
-	szone_error(szone, "incorrect checksum for freed object "
-	  "- object was probably modified after being freed, break at szone_error to debug", ptr);
-    }
-}
-
-static INLINE void
-free_list_set_checksum(szone_t *szone, free_list_t *ptr)
-{
-    // We always set checksum, as testing whether to do it (based on
-    // szone->debug_flags) is slower than just doing it
-    // XXX not necessarily true for LP64 case
-    ptr->checksum = ((uintptr_t)ptr->previous) ^ ((uintptr_t)ptr->next) ^ CHECKSUM_MAGIC;
-}
-
-static unsigned
-free_list_count(const free_list_t *ptr)
-{
-    unsigned	count = 0;
-
-    while (ptr) {
-	count++;
-	ptr = ptr->next;
-    }
-    return count;
-}
-
-/* XXX inconsistent use of BITMAP32 and BITARRAY operations could be cleaned up */
-
-#define BITMAP32_SET(bitmap,bit) 	(bitmap |= 1 << (bit))
-#define BITMAP32_CLR(bitmap,bit)	(bitmap &= ~ (1 << (bit)))
-#define BITMAP32_BIT(bitmap,bit) 	((bitmap >> (bit)) & 1)
-
-#define BITMAP32_FFS(bitmap) (ffs(bitmap))
-    // returns bit # of first bit that's one, starting at 1 (returns 0 if !bitmap)
-
-/*********************	TINY FREE LIST UTILITIES	************************/
-
-// We encode the meta-headers as follows:
-// Each quantum has an associated set of 2 bits:
-// block_header when 1 says this block is the beginning of a block
-// in_use when 1 says this block is in use
-// so a block in use of size 3 is 1-1 0-X 0-X
-// for a free block TINY_FREE_SIZE(ptr) carries the size and the bits are 1-0 X-X X-X
-// for a block middle the bits are 0-0
-
-// Attention double evaluation for these
-#define BITARRAY_SET(bits,index)	(bits[index>>3] |= (1 << (index & 7)))
-#define BITARRAY_CLR(bits,index)	(bits[index>>3] &= ~(1 << (index & 7)))
-#define BITARRAY_BIT(bits,index)	(((bits[index>>3]) >> (index & 7)) & 1)
-
-// Following is for start<8 and end<=start+32
-#define BITARRAY_MCLR_LESS_32(bits,start,end)				\
-do {									\
-    unsigned char	*_bits = (bits);				\
-    unsigned	_end = (end);						\
-    switch (_end >> 3) {						\
-	case 4: _bits[4] &= ~ ((1 << (_end - 32)) - 1); _end = 32;	\
-	case 3: _bits[3] &= ~ ((1 << (_end - 24)) - 1); _end = 24;	\
-	case 2: _bits[2] &= ~ ((1 << (_end - 16)) - 1); _end = 16;	\
-	case 1: _bits[1] &= ~ ((1 << (_end - 8)) - 1); _end = 8;	\
-	case 0: _bits[0] &= ~ ((1 << _end) - (1 << (start)));		\
-    }									\
-} while (0)
-
-#if 0	// Simple but slow version
-#warning Slow version in effect
-#define BITARRAY_MCLR(bits,index,num)					\
-do {									\
-    unsigned	_ctr = (num);						\
-    unsigned	_cur = (index);						\
-									\
-    while (_ctr--) {BITARRAY_CLR(bits,_cur); _cur++; }			\
-} while (0)
-#else
-
-// Following is for num <= 32
-#define BITARRAY_MCLR(bits,index,num)					\
-do {									\
-    unsigned		_index = (index);				\
-    unsigned char	*_rebased = (bits) + (_index >> 3);		\
-									\
-    _index &= 7;							\
-    BITARRAY_MCLR_LESS_32(_rebased, _index, _index + (num));		\
-} while (0)
-#endif
-
-static INLINE msize_t
-get_tiny_meta_header(const void *ptr, boolean_t *is_free)
-{
-    // returns msize and is_free
-    // may return 0 for the msize component (meaning 65536)
-    unsigned char	*block_header;
-    unsigned char	*in_use;
-    msize_t		index;
-    unsigned		byte_index;
-
-    block_header = TINY_BLOCK_HEADER_FOR_PTR(ptr);
-    index = TINY_INDEX_FOR_PTR(ptr);
-    byte_index = index >> 3;
-      
-    block_header += byte_index;
-    index &= 7;
-    *is_free = 0;
-    if (!BITMAP32_BIT(*block_header, index))
-	return 0;
-    in_use = TINY_INUSE_FOR_HEADER(block_header);
-    if (!BITMAP32_BIT(*in_use, index)) {
-	*is_free = 1;
-	return TINY_FREE_SIZE(ptr);
-    }
-    uint32_t	*addr = (uint32_t *)((uintptr_t)block_header & ~3);
-    uint32_t	word0 = OSReadLittleInt32(addr, 0) >> index;
-    uint32_t	word1 = OSReadLittleInt32(addr, 4) << (8 - index);
-    uint32_t	bits = (((uintptr_t)block_header & 3) * 8);	// precision loss on LP64 OK here
-    uint32_t	word = (word0 >> bits) | (word1 << (24 - bits));
-    uint32_t	result = ffs(word >> 1);
-    return result;
-}
-
-static INLINE void
-set_tiny_meta_header_in_use(const void *ptr, msize_t msize)
-{
-    unsigned char	*block_header;
-    unsigned char	*in_use;
-    msize_t		index;
-    unsigned		byte_index;
-    msize_t		clr_msize;
-    unsigned		end_bit;
-	
-    block_header = TINY_BLOCK_HEADER_FOR_PTR(ptr);
-    index = TINY_INDEX_FOR_PTR(ptr);
-    byte_index = index >> 3;
-    
-#if DEBUG_MALLOC
-    if (msize >= 32)
-	malloc_printf("set_tiny_meta_header_in_use() invariant broken %p %d\n", ptr, msize);
-    if ((unsigned)index + (unsigned)msize > 0x10000)
-	malloc_printf("set_tiny_meta_header_in_use() invariant broken (2) %p %d\n", ptr, msize);
-#endif
-    block_header += byte_index;
-    index &= 7;
-    BITMAP32_SET(*block_header, index); 
-    in_use = TINY_INUSE_FOR_HEADER(block_header);
-    BITMAP32_SET(*in_use, index); 
-    index++; 
-    clr_msize = msize-1;
-    if (clr_msize) {
-	byte_index = index >> 3;
-	block_header += byte_index; in_use += byte_index;
-	index &= 7;
-	end_bit = index + clr_msize;
-	BITARRAY_MCLR_LESS_32(block_header, index, end_bit);
-	BITARRAY_MCLR_LESS_32(in_use, index, end_bit);
-    }
-    BITARRAY_SET(block_header, index+clr_msize); // we set the block_header bit for the following block to reaffirm next block is a block
-#if DEBUG_MALLOC
-    {
-	boolean_t ff;
-	msize_t	mf;
-	
-	mf = get_tiny_meta_header(ptr, &ff);
-	if (msize != mf) {
-	    malloc_printf("setting header for tiny in_use %p : %d\n", ptr, msize);
-	    malloc_printf("reading header for tiny %p : %d %d\n", ptr, mf, ff);
-	}
-    }
-#endif
-}
-
-static INLINE void
-set_tiny_meta_header_middle(const void *ptr)
-{
-    // indicates this block is in the middle of an in use block
-    unsigned char	*block_header;
-    unsigned char	*in_use;
-    msize_t		index;
-
-    block_header = TINY_BLOCK_HEADER_FOR_PTR(ptr);
-    in_use = TINY_INUSE_FOR_HEADER(block_header);
-    index = TINY_INDEX_FOR_PTR(ptr);
-
-    BITARRAY_CLR(block_header, index);
-    BITARRAY_CLR(in_use, index); 
-    TINY_FREE_SIZE(ptr) = 0;
-}
-
-static INLINE void
-set_tiny_meta_header_free(const void *ptr, msize_t msize)
-{
-    // !msize is acceptable and means 65536
-    unsigned char	*block_header;
-    unsigned char	*in_use;
-    msize_t		index;
-
-    block_header = TINY_BLOCK_HEADER_FOR_PTR(ptr);
-    in_use = TINY_INUSE_FOR_HEADER(block_header);
-    index = TINY_INDEX_FOR_PTR(ptr);
-
-#if DEBUG_MALLOC
-    if ((unsigned)index + (unsigned)msize > 0x10000) {
-	malloc_printf("setting header for tiny free %p msize too large: %d\n", ptr, msize);
-    }
-#endif
-    BITARRAY_SET(block_header, index); BITARRAY_CLR(in_use, index); 
-    TINY_FREE_SIZE(ptr) = msize;
-    // mark the end of this block
-    if (msize) {	// msize==0 => the whole region is free
-	void	*follower = FOLLOWING_TINY_PTR(ptr, msize);
-	TINY_PREVIOUS_MSIZE(follower) = msize;
-    }
-#if DEBUG_MALLOC
-    boolean_t	ff;
-    msize_t	mf = get_tiny_meta_header(ptr, &ff);
-    if ((msize != mf) || !ff) {
-	malloc_printf("setting header for tiny free %p : %d\n", ptr, msize);
-	malloc_printf("reading header for tiny %p : %d %d\n", ptr, mf, ff);
-    }
-#endif
-}
-
-static INLINE boolean_t
-tiny_meta_header_is_free(const void *ptr)
-{
-    // returns msize and is_free shifted by 16
-    // may return 0 for the msize component (meaning 65536)
-    unsigned char	*block_header;
-    unsigned char	*in_use;
-    msize_t		index;
-
-    block_header = TINY_BLOCK_HEADER_FOR_PTR(ptr);
-    in_use = TINY_INUSE_FOR_HEADER(block_header);
-    index = TINY_INDEX_FOR_PTR(ptr);
-    if (!BITARRAY_BIT(block_header, index))
-	return 0;
-    return !BITARRAY_BIT(in_use, index);
-}
-
-static INLINE void *
-tiny_previous_preceding_free(void *ptr, msize_t *prev_msize)
-{
-    // returns the previous block, assuming and verifying it's free
-    unsigned char	*block_header;
-    unsigned char	*in_use;
-    msize_t		index;
-    msize_t		previous_msize;
-    msize_t		previous_index;
-    void		*previous_ptr;
-
-    block_header = TINY_BLOCK_HEADER_FOR_PTR(ptr);
-    in_use = TINY_INUSE_FOR_HEADER(block_header);
-    index = TINY_INDEX_FOR_PTR(ptr);
-    
-    if (!index)
-	return NULL;
-    if ((previous_msize = TINY_PREVIOUS_MSIZE(ptr)) > index)
-	return NULL;
-    
-    previous_index = index - previous_msize;
-    previous_ptr = (void *)(TINY_REGION_FOR_PTR(ptr) + TINY_BYTES_FOR_MSIZE(previous_index));
-    if (TINY_FREE_SIZE(previous_ptr) != previous_msize)
-	return NULL;
-
-    if (!BITARRAY_BIT(block_header, previous_index))
-	return NULL;
-    if (BITARRAY_BIT(in_use, previous_index))
-	return NULL;
-    
-    // conservative check did match true check
-    *prev_msize = previous_msize;
-    return previous_ptr;
-}
-
-static INLINE void
-tiny_free_list_add_ptr(szone_t *szone, void *ptr, msize_t msize)
-{
-    // Adds an item to the proper free list
-    // Also marks the meta-header of the block properly
-    // Assumes szone has been locked
-    grain_t	slot = (!msize || (msize >= NUM_TINY_SLOTS)) ? NUM_TINY_SLOTS - 1 : msize - 1;
-    free_list_t	*free_ptr = ptr;
-    free_list_t	*free_head = szone->tiny_free_list[slot];
-
-#if DEBUG_MALLOC
-    if (LOG(szone,ptr)) {
-	malloc_printf("in tiny_free_list_add_ptr(), ptr=%p, msize=%d\n", ptr, msize);
-    }
-    if (((unsigned)ptr) & (TINY_QUANTUM - 1)) {
-	szone_error(szone, "tiny_free_list_add_ptr: Unaligned ptr", ptr);
-    }
-#endif
-    set_tiny_meta_header_free(ptr, msize);
-    if (free_head) {
-	free_list_checksum(szone, free_head, __PRETTY_FUNCTION__);
-#if DEBUG_MALLOC
-	if (free_head->previous) {
-	    malloc_printf("ptr=%p slot=%d free_head=%p previous=%p\n", ptr, slot, free_head, free_head->previous);
-	    szone_error(szone, "tiny_free_list_add_ptr: Internal invariant broken (free_head->previous)", ptr);
-	}
-	if (! tiny_meta_header_is_free(free_head)) {
-	    malloc_printf("ptr=%p slot=%d free_head=%p\n", ptr, slot, free_head);
-	    szone_error(szone, "tiny_free_list_add_ptr: Internal invariant broken (free_head is not a free pointer)", ptr);
-	}
-#endif
-	free_head->previous = free_ptr;
-	free_list_set_checksum(szone, free_head);
-    } else {
-	BITMAP32_SET(szone->tiny_bitmap, slot);
-    }
-    free_ptr->previous = NULL;
-    free_ptr->next = free_head;
-    free_list_set_checksum(szone, free_ptr);
-    szone->tiny_free_list[slot] = free_ptr;
-}
-
-static INLINE void
-tiny_free_list_remove_ptr(szone_t *szone, void *ptr, msize_t msize)
-{
-    // Removes item in the proper free list
-    // msize could be read, but all callers have it so we pass it in
-    // Assumes szone has been locked
-    grain_t	slot = (!msize || (msize >= NUM_TINY_SLOTS)) ? NUM_TINY_SLOTS - 1 : msize - 1;
-    free_list_t	*free_ptr = ptr;
-    free_list_t	*next = free_ptr->next;
-    free_list_t	*previous = free_ptr->previous;
-
-#if DEBUG_MALLOC
-    if (LOG(szone,ptr)) {
-	malloc_printf("In tiny_free_list_remove_ptr(), ptr=%p, msize=%d\n", ptr, msize);
-    }
-#endif
-    free_list_checksum(szone, free_ptr, __PRETTY_FUNCTION__);
-    if (!previous) {
-	// The block to remove is the head of the free list
-#if DEBUG_MALLOC
-	if (szone->tiny_free_list[slot] != ptr) {
-	    malloc_printf("ptr=%p slot=%d msize=%d szone->tiny_free_list[slot]=%p\n",
-	      ptr, slot, msize, szone->tiny_free_list[slot]);
-	    szone_error(szone, "tiny_free_list_remove_ptr: Internal invariant broken (szone->tiny_free_list[slot])", ptr);
-	    return;
-	}
-#endif
-	szone->tiny_free_list[slot] = next;
-	if (!next) BITMAP32_CLR(szone->tiny_bitmap, slot);
-    } else {
-	previous->next = next;
-	free_list_set_checksum(szone, previous);
-    }
-    if (next) {
-	next->previous = previous;
-	free_list_set_checksum(szone, next);
-    }
-}
-
-/*
- * Find the tiny region containing (ptr) (if any).
- *
- * We take advantage of the knowledge that tiny regions are always (1 << TINY_BLOCKS_ALIGN) aligned.
- */
-static INLINE tiny_region_t *
-tiny_region_for_ptr_no_lock(szone_t *szone, const void *ptr)
-{
-    tiny_region_t *region;
-    tiny_region_t rbase;
-    int	i;
-    
-    /* mask off irrelevant lower bits */
-    rbase = TINY_REGION_FOR_PTR(ptr);
-    /* iterate over allocated regions - XXX not terribly efficient for large number of regions */
-    for (i = szone->num_tiny_regions, region = szone->tiny_regions; i > 0; i--, region++)
-	if (rbase == *region)
-	    return(region);
-    return(NULL);
-}
-
-static INLINE void
-tiny_free_no_lock(szone_t *szone, tiny_region_t *region, void *ptr, msize_t msize)
-{
-    size_t	original_size = TINY_BYTES_FOR_MSIZE(msize);
-    void	*next_block = ((char *)ptr + original_size);
-    msize_t	previous_msize;
-    void	*previous;
-    msize_t	next_msize;
-    free_list_t	*big_free_block;
-    free_list_t	*after_next_block;
-    free_list_t	*before_next_block;
-
-#if DEBUG_MALLOC
-    if (LOG(szone,ptr)) {
-	malloc_printf("in tiny_free_no_lock(), ptr=%p, msize=%d\n", ptr, msize);
-    }
-    if (! msize) {
-	malloc_printf("in tiny_free_no_lock(), ptr=%p, msize=%d\n", ptr, msize);
-	szone_error(szone, "trying to free tiny block that is too small", ptr);
-    }
-#endif
-    // We try to coalesce this block with the preceeding one
-    previous = tiny_previous_preceding_free(ptr, &previous_msize);
-    if (previous) {
-#if DEBUG_MALLOC
-	if (LOG(szone, ptr) || LOG(szone,previous)) { 
-	    malloc_printf("in tiny_free_no_lock(), coalesced backwards for %p previous=%p\n", ptr, previous);
-	}
-#endif
-	tiny_free_list_remove_ptr(szone, previous, previous_msize);
-	ptr = previous;
-	msize += previous_msize;
-    }
-    // We try to coalesce with the next block
-    if ((next_block < TINY_REGION_END(*region)) && tiny_meta_header_is_free(next_block)) {
-	// The next block is free, we coalesce
-	next_msize = TINY_FREE_SIZE(next_block);
-#if DEBUG_MALLOC
-	if (LOG(szone, ptr) || LOG(szone, next_block)) {
-	    malloc_printf("in tiny_free_no_lock(), for ptr=%p, msize=%d coalesced forward=%p next_msize=%d\n",
-	      ptr, msize, next_block, next_msize);
-	}
-#endif
-	if (next_msize >= NUM_TINY_SLOTS) {
-	    // we take a short cut here to avoid removing next_block from the slot 31 freelist and then adding ptr back to slot 31
-	    msize += next_msize;
-	    big_free_block = (free_list_t *)next_block;
-	    after_next_block = big_free_block->next;
-	    before_next_block = big_free_block->previous;
-	    free_list_checksum(szone, big_free_block, __PRETTY_FUNCTION__);
-	    if (!before_next_block) {
-		szone->tiny_free_list[NUM_TINY_SLOTS-1] = ptr;
-	    } else {
-		before_next_block->next = ptr;
-		free_list_set_checksum(szone, before_next_block);
-	    }
-	    if (after_next_block) {
-		after_next_block->previous = ptr;
-		free_list_set_checksum(szone, after_next_block);
-	    }
-	    ((free_list_t *)ptr)->previous = before_next_block;
-	    ((free_list_t *)ptr)->next = after_next_block;
-	    free_list_set_checksum(szone, ptr);
-	    set_tiny_meta_header_free(ptr, msize);
-	    set_tiny_meta_header_middle(big_free_block); // clear the meta_header to enable coalescing backwards
-	    goto tiny_free_ending;
-	}
-	tiny_free_list_remove_ptr(szone, next_block, next_msize);
-	set_tiny_meta_header_middle(next_block); // clear the meta_header to enable coalescing backwards
-	msize += next_msize;
-    }
-    if ((szone->debug_flags & SCALABLE_MALLOC_DO_SCRIBBLE) && msize) {
-	memset(ptr, 0x55, TINY_BYTES_FOR_MSIZE(msize));
-    }
-    tiny_free_list_add_ptr(szone, ptr, msize);
-  tiny_free_ending:
-    // When in proper debug mode we write on the memory to help debug memory smashers
-    szone->num_tiny_objects--;
-    szone->num_bytes_in_tiny_objects -= original_size; // we use original_size and not msize to avoid double counting the coalesced blocks
-}
-
-static void *
-tiny_malloc_from_region_no_lock(szone_t *szone, msize_t msize)
-{
-    tiny_region_t	last_region, *new_regions;
-    void		*last_block, *ptr, *aligned_address;
-
-    // Allocates from the last region or a freshly allocated region
-    // Before anything we transform the tiny_bytes_free_at_end - if any - to a regular free block
-    if (szone->tiny_bytes_free_at_end) {
-	last_region = szone->tiny_regions[szone->num_tiny_regions-1];
-	last_block = TINY_REGION_END(last_region) - szone->tiny_bytes_free_at_end;
-	tiny_free_list_add_ptr(szone, last_block, TINY_MSIZE_FOR_BYTES(szone->tiny_bytes_free_at_end));
-	szone->tiny_bytes_free_at_end = 0;
-    }
-    // time to create a new region
-    aligned_address = allocate_pages(szone, TINY_REGION_SIZE, TINY_BLOCKS_ALIGN, 0, VM_MAKE_TAG(VM_MEMORY_MALLOC_TINY));
-    if (!aligned_address) {
-	// out of memory!
-	return NULL;
-    }
-    // We set the padding after block_header to be all 1
-    ((uint32_t *)(aligned_address + (1 << TINY_BLOCKS_ALIGN) + (NUM_TINY_BLOCKS >> 3)))[0] = ~0;
-    if (szone->num_tiny_regions == INITIAL_NUM_TINY_REGIONS) {
-	// XXX logic here fails after initial reallocation of tiny regions is exhausted (approx 4GB of
-	// tiny allocations)
-	new_regions = small_malloc_from_region_no_lock(szone, 16); // 16 * 512 bytes is plenty of tiny regions (more than 4,000)
-	if (!new_regions) return NULL;
-	memcpy(new_regions, szone->tiny_regions, INITIAL_NUM_TINY_REGIONS * sizeof(tiny_region_t));
-	szone->tiny_regions = new_regions; // we set the pointer after it's all ready to enable enumeration from another thread without locking
-    }
-    szone->tiny_regions[szone->num_tiny_regions] = aligned_address;
-    szone->num_tiny_regions ++; // we set the number after the pointer is all ready to enable enumeration from another thread without taking the lock
-    ptr = aligned_address; 
-    set_tiny_meta_header_in_use(ptr, msize);
-    szone->num_tiny_objects++;
-    szone->num_bytes_in_tiny_objects += TINY_BYTES_FOR_MSIZE(msize);
-    // We put a header on the last block so that it appears in use (for coalescing, etc...)
-    set_tiny_meta_header_in_use(ptr + TINY_BYTES_FOR_MSIZE(msize), 1);
-    szone->tiny_bytes_free_at_end = TINY_BYTES_FOR_MSIZE(NUM_TINY_BLOCKS - msize);
-#if DEBUG_MALLOC
-    if (LOG(szone,ptr)) {
-	malloc_printf("in tiny_malloc_from_region_no_lock(), ptr=%p, msize=%d\n", ptr, msize);
-    }
-#endif
-    return ptr;
-}
-
-static INLINE boolean_t
-try_realloc_tiny_in_place(szone_t *szone, void *ptr, size_t old_size, size_t new_size)
-{
-    // returns 1 on success
-    msize_t	index;
-    msize_t	old_msize;
-    unsigned	next_index;
-    void	*next_block;
-    boolean_t	is_free;
-    msize_t	next_msize, coalesced_msize, leftover_msize;
-    void	*leftover;
-
-    index = TINY_INDEX_FOR_PTR(ptr);
-    old_msize = TINY_MSIZE_FOR_BYTES(old_size);
-    next_index = index + old_msize;
-    
-    if (next_index >= NUM_TINY_BLOCKS) {
-	return 0;
-    }
-    next_block = (char *)ptr + old_size;
-    SZONE_LOCK(szone);
-    is_free = tiny_meta_header_is_free(next_block);
-    if (!is_free) {
-	SZONE_UNLOCK(szone);
-	return 0; // next_block is in use;
-    }
-    next_msize = TINY_FREE_SIZE(next_block);
-    if (old_size + TINY_MSIZE_FOR_BYTES(next_msize) < new_size) {
-	SZONE_UNLOCK(szone);
-	return 0; // even with next block, not enough
-    }
-    tiny_free_list_remove_ptr(szone, next_block, next_msize);
-    set_tiny_meta_header_middle(next_block); // clear the meta_header to enable coalescing backwards
-    coalesced_msize = TINY_MSIZE_FOR_BYTES(new_size - old_size + TINY_QUANTUM - 1);
-    leftover_msize = next_msize - coalesced_msize;
-    if (leftover_msize) {
-	leftover = next_block + TINY_BYTES_FOR_MSIZE(coalesced_msize);
-	tiny_free_list_add_ptr(szone, leftover, leftover_msize);
-    }
-    set_tiny_meta_header_in_use(ptr, old_msize + coalesced_msize);
-#if DEBUG_MALLOC
-    if (LOG(szone,ptr)) {
-	malloc_printf("in try_realloc_tiny_in_place(), ptr=%p, msize=%d\n", ptr, old_msize + coalesced_msize);
-    }
-#endif
-    szone->num_bytes_in_tiny_objects += TINY_BYTES_FOR_MSIZE(coalesced_msize);
-    SZONE_UNLOCK(szone);
-    CHECK(szone, __PRETTY_FUNCTION__);
-    return 1;
-}
-
-static boolean_t
-tiny_check_region(szone_t *szone, tiny_region_t *region)
-{
-    uintptr_t		start, ptr, region_end, follower;
-    boolean_t		prev_free = 0;
-    boolean_t		is_free;
-    msize_t		msize;
-    free_list_t		*free_head;
-
-    /* establish region limits */
-    start = (uintptr_t)TINY_REGION_ADDRESS(*region);
-    ptr = start;
-    region_end = (uintptr_t)TINY_REGION_END(*region);
-
-    /*
-     * The last region may have a trailing chunk which has not been converted into inuse/freelist
-     * blocks yet.
-     */
-    if (region == szone->tiny_regions + szone->num_tiny_regions - 1)
-	    region_end -= szone->tiny_bytes_free_at_end;
-
-
-    /*
-     * Scan blocks within the region.
-     */
-    while (ptr < region_end) {
-	/*
-	 * If the first block is free, and its size is 65536 (msize = 0) then the entire region is
-	 * free.
-	 */
-	msize = get_tiny_meta_header((void *)ptr, &is_free);
-	if (is_free && !msize && (ptr == start)) {
-	    return 1;
-	}
-
-	/*
-	 * If the block's size is 65536 (msize = 0) then since we're not the first entry the size is
-	 * corrupt.
-	 */
-	if (!msize) {
-	    malloc_printf("*** invariant broken for tiny block %p this msize=%d - size is too small\n",
-	      ptr, msize);
-	    return 0;
-	}
-
-	if (!is_free) {
-	    /*
-	     * In use blocks cannot be more than 31 quanta large.
-	     */
-	    prev_free = 0;
-	    if (msize > 31 * TINY_QUANTUM) {
-		malloc_printf("*** invariant broken for %p this tiny msize=%d[%p] - size is too large\n",
-		  ptr, msize, msize);
-		return 0;
-	    }
-	    /* move to next block */
-	    ptr += TINY_BYTES_FOR_MSIZE(msize);
-	} else {
-	    /*
-	     * Free blocks must have been coalesced, we cannot have a free block following another
-	     * free block.
-	     */
-	    if (prev_free) {
-		malloc_printf("*** invariant broken for free block %p this tiny msize=%d: two free blocks in a row\n",
-		  ptr, msize);
-		return 0;
-	    }
-	    prev_free = 1;
-	    /*
-	     * Check the integrity of this block's entry in its freelist.
-	     */
-	    free_head = (free_list_t *)ptr;
-	    free_list_checksum(szone, free_head, __PRETTY_FUNCTION__);
-	    if (free_head->previous && !tiny_meta_header_is_free(free_head->previous)) {
-		malloc_printf("*** invariant broken for %p (previous %p is not a free pointer)\n",
-		  ptr, free_head->previous);
-		return 0;
-	    }
-	    if (free_head->next && !tiny_meta_header_is_free(free_head->next)) {
-		malloc_printf("*** invariant broken for %p (next in free list %p is not a free pointer)\n",
-		  ptr, free_head->next);
-		return 0;
-	    }
-	    /*
-	     * Check the free block's trailing size value.
-	     */
-	    follower = (uintptr_t)FOLLOWING_TINY_PTR(ptr, msize);
-	    if ((follower != region_end) && (TINY_PREVIOUS_MSIZE(follower) != msize)) {
-		malloc_printf("*** invariant broken for tiny free %p followed by %p in region [%p-%p] "
-		  "(end marker incorrect) should be %d; in fact %d\n",
-		  ptr, follower, TINY_REGION_ADDRESS(*region), region_end, msize, TINY_PREVIOUS_MSIZE(follower));
-		return 0;
-	    }
-	    /* move to next block */
-	    ptr = follower;
-	}
-    }
-    /*
-     * Ensure that we scanned the entire region
-     */
-    if (ptr != region_end) {
-	malloc_printf("*** invariant broken for region end %p - %p\n", ptr, region_end);
-	return 0;
-    }
-    /*
-     * Check the trailing block's integrity.
-     */
-    if (region == szone->tiny_regions + szone->num_tiny_regions - 1) {
-	if (szone->tiny_bytes_free_at_end) {
-	    msize = get_tiny_meta_header((void *)ptr, &is_free);
-	    if (is_free || (msize != 1)) {
-		malloc_printf("*** invariant broken for blocker block %p - %d %d\n", ptr, msize, is_free);
-	    }
-	}
-    }
-    return 1;
-}
-
-static kern_return_t
-tiny_in_use_enumerator(task_t task, void *context, unsigned type_mask, vm_address_t region_address, unsigned short num_regions, size_t tiny_bytes_free_at_end, memory_reader_t reader, vm_range_recorder_t recorder)
-{
-    tiny_region_t	*regions;
-    unsigned		index = 0;
-    vm_range_t		buffer[MAX_RECORDER_BUFFER];
-    unsigned		count = 0;
-    kern_return_t	err;
-    tiny_region_t	region;
-    vm_range_t		range;
-    vm_range_t		admin_range;
-    vm_range_t		ptr_range;
-    unsigned char	*mapped_region;
-    unsigned char	*block_header;
-    unsigned char	*in_use;
-    unsigned		block_index;
-    unsigned		block_limit;
-    boolean_t		is_free;
-    msize_t		msize;
-    void		*mapped_ptr;
-    unsigned 		bit;
-    
-    err = reader(task, region_address, sizeof(tiny_region_t) * num_regions, (void **)&regions);
-    if (err) return err;
-    while (index < num_regions) {
-	// unsigned		num_in_use = 0;
-	// unsigned		num_free = 0;
-	region = regions[index];
-	range.address = (vm_address_t)TINY_REGION_ADDRESS(region);
-	range.size = (vm_size_t)TINY_REGION_SIZE;
-	if (type_mask & MALLOC_ADMIN_REGION_RANGE_TYPE) {
-	    admin_range.address = range.address + (1 << TINY_BLOCKS_ALIGN);
-	    admin_range.size = range.size - (1 << TINY_BLOCKS_ALIGN);
-	    recorder(task, context, MALLOC_ADMIN_REGION_RANGE_TYPE, &admin_range, 1);
-	}
-	if (type_mask & (MALLOC_PTR_REGION_RANGE_TYPE | MALLOC_ADMIN_REGION_RANGE_TYPE)) {
-	    ptr_range.address = range.address;
-	    ptr_range.size = 1 << TINY_BLOCKS_ALIGN;
-	    recorder(task, context, MALLOC_PTR_REGION_RANGE_TYPE, &ptr_range, 1);
-	}
-	if (type_mask & MALLOC_PTR_IN_USE_RANGE_TYPE) {
-	    err = reader(task, range.address, range.size, (void **)&mapped_region);
-	    if (err)
-		return err;
-	    block_header = (unsigned char *)(mapped_region + (1 << TINY_BLOCKS_ALIGN));
-	    in_use = block_header + (NUM_TINY_BLOCKS >> 3) + 4;
-	    block_index = 0;
-	    block_limit = NUM_TINY_BLOCKS;
-	    if (index == num_regions - 1)
-		block_limit -= TINY_MSIZE_FOR_BYTES(tiny_bytes_free_at_end);
-	    while (block_index < block_limit) {
-		is_free = !BITARRAY_BIT(in_use, block_index);
-		if (is_free) {
-		    mapped_ptr = mapped_region + TINY_BYTES_FOR_MSIZE(block_index);
-		    msize = TINY_FREE_SIZE(mapped_ptr);
-		    if (!msize)
-			break;
-		} else {
-		    msize = 1; 
-		    bit = block_index + 1;
-		    while (! BITARRAY_BIT(block_header, bit)) {
-			bit++;
-			msize ++;
-		    }
-		    buffer[count].address = range.address + TINY_BYTES_FOR_MSIZE(block_index);
-		    buffer[count].size = TINY_BYTES_FOR_MSIZE(msize);
-		    count++;
-		    if (count >= MAX_RECORDER_BUFFER) {
-			recorder(task, context, MALLOC_PTR_IN_USE_RANGE_TYPE, buffer, count);
-			count = 0;
-		    }
-		}
-		block_index += msize;
-	    }
-	}
-	index++;
-    }
-    if (count) {
-	recorder(task, context, MALLOC_PTR_IN_USE_RANGE_TYPE, buffer, count);
-    }
-    return 0;
-}
-
-static INLINE void *
-tiny_malloc_from_free_list(szone_t *szone, msize_t msize)
-{
-    // Assumes we've locked the region
-    free_list_t		*ptr;
-    msize_t		this_msize;
-    grain_t		slot = msize - 1;
-    free_list_t		**free_list = szone->tiny_free_list;
-    free_list_t		**the_slot = free_list + slot;
-    free_list_t		*next;
-    free_list_t		**limit;
-    unsigned		bitmap;
-    msize_t		leftover_msize;
-    free_list_t		*leftover_ptr;
-
-    /*
-     * Look for an exact match by checking the freelist for this msize.
-     */
-    ptr = *the_slot;
-    if (ptr) {
-	next = ptr->next;
-	if (next) {
-	    next->previous = NULL;
-	    free_list_set_checksum(szone, next);
-	}
-	*the_slot = next;
-	this_msize = msize;
-#if DEBUG_MALLOC
-	if (LOG(szone, ptr)) {
-	    malloc_printf("in tiny_malloc_from_free_list(), exact match ptr=%p, this_msize=%d\n", ptr, this_msize);
-	}
-#endif
-	goto return_tiny_alloc;
-    }
-
-    /*
-     * Iterate over freelists for larger blocks looking for the next-largest block.
-     */
-    bitmap = szone->tiny_bitmap & ~ ((1 << slot) - 1);
-    if (!bitmap)
-	goto try_tiny_malloc_from_end;
-    slot = BITMAP32_FFS(bitmap) - 1;
-    limit = free_list + NUM_TINY_SLOTS - 1;
-    free_list += slot;
-    while (free_list < limit) {
-	// try bigger grains
-	ptr = *free_list;
-	if (ptr) {
-	    next = ptr->next;
-	    if (next) {
-		next->previous = NULL;
-		free_list_set_checksum(szone, next);
-	    }
-	    *free_list = next;
-	    this_msize = TINY_FREE_SIZE(ptr);
-#if DEBUG_MALLOC
-	    if (LOG(szone, ptr)) {
-		malloc_printf("in tiny_malloc_from_free_list(), bigger grain ptr=%p, msize=%d this_msize=%d\n", ptr, msize, this_msize);
-	    }
-#endif
-	    goto add_leftover_and_proceed;
-	}
-	free_list++;
-    }
-    // we are now looking at the last slot (31)
-    ptr = *limit;
-    if (ptr) {
-	this_msize = TINY_FREE_SIZE(ptr);
-	next = ptr->next;
-	if (this_msize - msize >= NUM_TINY_SLOTS) {
-	    // the leftover will go back to the free list, so we optimize by modifying the free list rather than removing the head and then adding back
-	    leftover_msize = this_msize - msize;
-	    leftover_ptr = (free_list_t *)((unsigned char *)ptr + TINY_BYTES_FOR_MSIZE(msize));
-	    *limit = leftover_ptr;
-	    if (next) {
-		next->previous = leftover_ptr;
-		free_list_set_checksum(szone, next);
-	    }
-	    leftover_ptr->next = next;
-	    leftover_ptr->previous = NULL;
-	    free_list_set_checksum(szone, leftover_ptr);
-	    set_tiny_meta_header_free(leftover_ptr, leftover_msize);
-#if DEBUG_MALLOC
-	    if (LOG(szone,ptr)) {
-		malloc_printf("in tiny_malloc_from_free_list(), last slot ptr=%p, msize=%d this_msize=%d\n", ptr, msize, this_msize);
-	    }
-#endif
-	    this_msize = msize;
-	    goto return_tiny_alloc;
-	}
-	*limit = next;
-	if (next) {
-	    next->previous = NULL;
-	    free_list_set_checksum(szone, next);
-	}
-	goto add_leftover_and_proceed;
-    }
-try_tiny_malloc_from_end:
-    // Let's see if we can use szone->tiny_bytes_free_at_end
-    if (szone->tiny_bytes_free_at_end >= TINY_BYTES_FOR_MSIZE(msize)) {
-	ptr = (free_list_t *)(TINY_REGION_END(szone->tiny_regions[szone->num_tiny_regions-1]) - szone->tiny_bytes_free_at_end);
-	szone->tiny_bytes_free_at_end -= TINY_BYTES_FOR_MSIZE(msize);
-	if (szone->tiny_bytes_free_at_end) {
-	    // let's add an in use block after ptr to serve as boundary
-	    set_tiny_meta_header_in_use((unsigned char *)ptr + TINY_BYTES_FOR_MSIZE(msize), 1);
-	}
-	this_msize = msize;
-#if DEBUG_MALLOC
-	if (LOG(szone, ptr)) {
-	    malloc_printf("in tiny_malloc_from_free_list(), from end ptr=%p, msize=%d\n", ptr, msize);
-	}
-#endif
-	goto return_tiny_alloc;
-    }
-    return NULL;
-add_leftover_and_proceed:
-    if (!this_msize || (this_msize > msize)) {
-	leftover_msize = this_msize - msize;
-	leftover_ptr = (free_list_t *)((unsigned char *)ptr + TINY_BYTES_FOR_MSIZE(msize));
-#if DEBUG_MALLOC
-	if (LOG(szone,ptr)) {
-	    malloc_printf("in tiny_malloc_from_free_list(), adding leftover ptr=%p, this_msize=%d\n", ptr, this_msize);
-	}
-#endif
-	tiny_free_list_add_ptr(szone, leftover_ptr, leftover_msize);
-	this_msize = msize;
-    }
-return_tiny_alloc:
-    szone->num_tiny_objects++;
-    szone->num_bytes_in_tiny_objects += TINY_BYTES_FOR_MSIZE(this_msize);
-#if DEBUG_MALLOC
-    if (LOG(szone,ptr)) {
-	malloc_printf("in tiny_malloc_from_free_list(), ptr=%p, this_msize=%d, msize=%d\n", ptr, this_msize, msize);
-    }
-#endif
-    set_tiny_meta_header_in_use(ptr, this_msize);
-    return ptr;
-}
-
-static INLINE void *
-tiny_malloc_should_clear(szone_t *szone, msize_t msize, boolean_t cleared_requested)
-{
-    boolean_t	locked = 0;
-    void	*ptr;
-
-#if DEBUG_MALLOC
-    if (!msize) {
-	szone_error(szone, "invariant broken (!msize) in allocation (region)", NULL);
-	return(NULL);
-    }
-#endif
-#if TINY_CACHE
-    ptr = szone->last_tiny_free;
-    if ((((uintptr_t)ptr) & (TINY_QUANTUM - 1)) == msize) {
-	// we have a candidate - let's lock to make sure
-	LOCK_AND_NOTE_LOCKED(szone, locked);
-	if (ptr == szone->last_tiny_free) {
-	    szone->last_tiny_free = NULL;
-	    SZONE_UNLOCK(szone);
-	    CHECK(szone, __PRETTY_FUNCTION__);
-	    ptr = (void *)((uintptr_t)ptr & ~ (TINY_QUANTUM - 1));
-	    if (cleared_requested) {
-		memset(ptr, 0, TINY_BYTES_FOR_MSIZE(msize));
-	    }
-#if DEBUG_MALLOC
-	    if (LOG(szone,ptr)) {
-		malloc_printf("in tiny_malloc_should_clear(), tiny cache ptr=%p, msize=%d\n", ptr, msize);
-	    }
-#endif
-	    return ptr;
-	}
-    }
-#endif
-    // Except in rare occasions where we need to add a new region, we are going to end up locking, so we might as well lock right away to avoid doing unnecessary optimistic probes
-    if (!locked) LOCK_AND_NOTE_LOCKED(szone, locked);
-    ptr = tiny_malloc_from_free_list(szone, msize);
-    if (ptr) {
-	SZONE_UNLOCK(szone);
-	CHECK(szone, __PRETTY_FUNCTION__);
-	if (cleared_requested) {
-	    memset(ptr, 0, TINY_BYTES_FOR_MSIZE(msize));
-	}
-	return ptr;
-    }
-    ptr = tiny_malloc_from_region_no_lock(szone, msize);
-    // we don't clear because this freshly allocated space is pristine
-    SZONE_UNLOCK(szone);
-    CHECK(szone, __PRETTY_FUNCTION__);
-    return ptr;
-}
-
-static INLINE void
-free_tiny(szone_t *szone, void *ptr, tiny_region_t *tiny_region)
-{
-    msize_t	msize;
-    boolean_t	is_free;
-#if TINY_CACHE
-    void *ptr2;
-#endif
-
-    // ptr is known to be in tiny_region
-    SZONE_LOCK(szone);
-#if TINY_CACHE
-    ptr2 = szone->last_tiny_free;
-    /* check that we don't already have this pointer in the cache */
-    if (ptr == (void *)((uintptr_t)ptr2 & ~ (TINY_QUANTUM - 1))) {
-	szone_error(szone, "double free", ptr);
-	return;
-    }
-#endif /* TINY_CACHE */
-    msize = get_tiny_meta_header(ptr, &is_free);
-    if (is_free) {
-	szone_error(szone, "double free", ptr);
-	return;
-    }
-#if DEBUG_MALLOC
-    if (!msize) {
-	malloc_printf("*** szone_free() block in use is too large: %p\n", ptr);
-	return;
-    }
-#endif
-#if TINY_CACHE
-    if (msize < TINY_QUANTUM) {	// to see if the bits fit in the last 4 bits
-	szone->last_tiny_free = (void *)(((uintptr_t)ptr) | msize);
-	if (!ptr2) {
-	    SZONE_UNLOCK(szone);
-	    CHECK(szone, __PRETTY_FUNCTION__);
-	    return;
-	}
-	msize = (uintptr_t)ptr2 & (TINY_QUANTUM - 1);
-	ptr = (void *)(((uintptr_t)ptr2) & ~(TINY_QUANTUM - 1));
-	tiny_region = tiny_region_for_ptr_no_lock(szone, ptr);
-	if (!tiny_region) {
-	    szone_error(szone, "double free (tiny cache)", ptr);
-	}
-    }
-#endif
-    tiny_free_no_lock(szone, tiny_region, ptr, msize);
-    SZONE_UNLOCK(szone);
-    CHECK(szone, __PRETTY_FUNCTION__);
-}
-
-static void
-print_tiny_free_list(szone_t *szone)
-{
-    grain_t	slot = 0;
-    free_list_t	*ptr;
-
-    malloc_printf("tiny free sizes: ");
-    while (slot < NUM_TINY_SLOTS) {
-	ptr = szone->tiny_free_list[slot];
-	if (ptr) {
-	    malloc_printf("%s%y[%d]; ", (slot == NUM_TINY_SLOTS-1) ? ">=" : "", (slot+1)*TINY_QUANTUM, free_list_count(ptr));
-	}
-	slot++;
-    }
-}
-
-static void
-print_tiny_region(boolean_t verbose, tiny_region_t region, size_t bytes_at_end)
-{
-    unsigned	counts[1024];
-    unsigned	in_use = 0;
-    uintptr_t	start = (uintptr_t)TINY_REGION_ADDRESS(region);
-    uintptr_t	current = start;
-    uintptr_t	limit =  (uintptr_t)TINY_REGION_END(region) - bytes_at_end;
-    boolean_t	is_free;
-    msize_t	msize;
-    unsigned	ci;
-    
-    memset(counts, 0, 1024 * sizeof(unsigned));
-    while (current < limit) {
-	msize = get_tiny_meta_header((void *)current, &is_free);
-	if (is_free & !msize && (current == start)) {
-	    // first block is all free
-	    break;
-	}
-	if (!msize) {
-	    malloc_printf("*** error with %p: msize=%d\n", (void *)current, (unsigned)msize);
-	    break;
-	}
-	if (!is_free) {
-	    // block in use
-	    if (msize > 32)
-		malloc_printf("*** error at %p msize for in_use is %d\n", (void *)current, msize);
-	    if (msize < 1024)
-		counts[msize]++;
-	    in_use++;
-	}
-	current += TINY_BYTES_FOR_MSIZE(msize);
-    }
-    malloc_printf("Tiny region [%p-%p, %y]\t", (void *)start, TINY_REGION_END(region), (int)TINY_REGION_SIZE);
-    malloc_printf("In_use=%d ", in_use);
-    if (bytes_at_end) malloc_printf("untouched=%y ", bytes_at_end);
-    if (verbose && in_use) {
-	malloc_printf("\tSizes in use: ");
-	for (ci = 0; ci < 1024; ci++)
-	    if (counts[ci])
-		malloc_printf("%d[%d]", TINY_BYTES_FOR_MSIZE(ci), counts[ci]);
-    }
-    malloc_printf("\n");
-}
-
-static boolean_t
-tiny_free_list_check(szone_t *szone, grain_t slot)
-{
-    unsigned	count = 0;
-    free_list_t	*ptr = szone->tiny_free_list[slot];
-    free_list_t	*previous = NULL;
-    boolean_t	is_free;
-
-    CHECK_LOCKED(szone, __PRETTY_FUNCTION__);
-    while (ptr) {
-	free_list_checksum(szone, ptr, __PRETTY_FUNCTION__);
-	is_free = tiny_meta_header_is_free(ptr);
-	if (! is_free) {
-	    malloc_printf("*** in-use ptr in free list slot=%d count=%d ptr=%p\n", slot, count, ptr);
-	    return 0;
-	}
-	if (((uintptr_t)ptr) & (TINY_QUANTUM - 1)) {
-	    malloc_printf("*** inaligned ptr in free list slot=%d  count=%d ptr=%p\n", slot, count, ptr);
-	    return 0;
-	}
-	if (!tiny_region_for_ptr_no_lock(szone, ptr)) {
-	    malloc_printf("*** itr not in szone slot=%d  count=%d ptr=%p\n", slot, count, ptr);
-	    return 0;
-	}
-	if (ptr->previous != previous) {
-	    malloc_printf("*** irevious incorrectly set slot=%d  count=%d ptr=%p\n", slot, count, ptr);
-	    return 0;
-	}
-	previous = ptr;
-	ptr = ptr->next;
-	count++;
-    }
-    return 1;
-}
-
-/*********************	SMALL FREE LIST UTILITIES	************************/
-
-/*
- * Mark a block as free.  Only the first quantum of a block is marked thusly,
- * the remainder are marked "middle".
- */
-static INLINE void
-small_meta_header_set_is_free(msize_t *meta_headers, unsigned index, msize_t msize)
-{
-
-    meta_headers[index] = msize | SMALL_IS_FREE;
-}
-
-/*
- * Mark a block as in use.  Only the first quantum of a block is marked thusly,
- * the remainder are marked "middle".
- */
-static INLINE void
-small_meta_header_set_in_use(msize_t *meta_headers, msize_t index, msize_t msize)
-{
-
-    meta_headers[index] = msize;
-}
-
-/*
- * Mark a quantum as being the second or later in a block.
- */
-static INLINE void
-small_meta_header_set_middle(msize_t *meta_headers, msize_t index)
-{
-
-    meta_headers[index] = 0;
-}
-
-// Adds an item to the proper free list
-// Also marks the header of the block properly
-// Assumes szone has been locked    
-static void
-small_free_list_add_ptr(szone_t *szone, void *ptr, msize_t msize)
-{
-    grain_t	grain = (msize <= NUM_SMALL_SLOTS) ? msize - 1 : NUM_SMALL_SLOTS - 1;
-    free_list_t	*free_ptr = ptr;
-    free_list_t	*free_head = szone->small_free_list[grain];
-    void	*follower;
-
-    CHECK_LOCKED(szone, __PRETTY_FUNCTION__);
-#if DEBUG_MALLOC
-    if (LOG(szone,ptr)) {
-	malloc_printf("in small_free_list_add_ptr(), ptr=%p, msize=%d\n", ptr, msize);
-    }
-    if (((uintptr_t)ptr) & (SMALL_QUANTUM - 1)) {
-	szone_error(szone, "small_free_list_add_ptr: Unaligned ptr", ptr);
-    }
-#endif
-    if (free_head) {
-	free_list_checksum(szone, free_head, __PRETTY_FUNCTION__);
-#if DEBUG_MALLOC
-	if (free_head->previous) {
-	    malloc_printf("ptr=%p grain=%d free_head=%p previous=%p\n",
-	      ptr, grain, free_head, free_head->previous);
-	    szone_error(szone, "small_free_list_add_ptr: Internal invariant broken (free_head->previous)", ptr);
-	}
-	if (!SMALL_PTR_IS_FREE(free_head)) {
-	    malloc_printf("ptr=%p grain=%d free_head=%p\n", ptr, grain, free_head);
-	    szone_error(szone, "small_free_list_add_ptr: Internal invariant broken (free_head is not a free pointer)", ptr);
-	}
-#endif
-	free_head->previous = free_ptr;
-	free_list_set_checksum(szone, free_head);
-    } else {
-	BITMAP32_SET(szone->small_bitmap, grain);
-    }
-    free_ptr->previous = NULL;
-    free_ptr->next = free_head;
-    free_list_set_checksum(szone, free_ptr);
-    szone->small_free_list[grain] = free_ptr;
-    follower = ptr + SMALL_BYTES_FOR_MSIZE(msize);
-    SMALL_PREVIOUS_MSIZE(follower) = msize;
-}
-
-// Removes item in the proper free list
-// msize could be read, but all callers have it so we pass it in
-// Assumes szone has been locked
-static void
-small_free_list_remove_ptr(szone_t *szone, void *ptr, msize_t msize)
-{
-    grain_t	grain = (msize <= NUM_SMALL_SLOTS) ? msize - 1 : NUM_SMALL_SLOTS - 1;
-    free_list_t	*free_ptr = ptr;
-    free_list_t	*next = free_ptr->next;
-    free_list_t	*previous = free_ptr->previous;
-
-    CHECK_LOCKED(szone, __PRETTY_FUNCTION__);
-#if DEBUG_MALLOC
-    if (LOG(szone,ptr)) {
-	malloc_printf("in small_free_list_remove_ptr(), ptr=%p, msize=%d\n", ptr, msize);
-    }
-#endif
-    free_list_checksum(szone, free_ptr, __PRETTY_FUNCTION__);
-    if (!previous) {
-#if DEBUG_MALLOC
-	if (szone->small_free_list[grain] != ptr) {
-	    malloc_printf("ptr=%p grain=%d msize=%d szone->small_free_list[grain]=%p\n",
-	      ptr, grain, msize, szone->small_free_list[grain]);
-	    szone_error(szone, "small_free_list_remove_ptr: Internal invariant broken (szone->small_free_list[grain])", ptr);
-	    return;
-	}
-#endif
-	szone->small_free_list[grain] = next;
-	if (!next) BITMAP32_CLR(szone->small_bitmap, grain);
-    } else {
-	previous->next = next;
-	free_list_set_checksum(szone, previous);
-    }
-    if (next) {
-	next->previous = previous;
-	free_list_set_checksum(szone, next);
-    }
-}
-
-static INLINE small_region_t *
-small_region_for_ptr_no_lock(szone_t *szone, const void *ptr)
-{
-    small_region_t	*region;
-    small_region_t	rbase;
-    int			i;
-    
-    /* find assumed heap/region base */
-    rbase = SMALL_REGION_FOR_PTR(ptr);
-
-    /* scan existing regions for a match */
-    for (i = szone->num_small_regions, region = szone->small_regions; i > 0; i--, region++)
-	if (rbase == *region)
-	    return(region);
-    return(NULL);
-}
-
-static INLINE void
-small_free_no_lock(szone_t *szone, small_region_t *region, void *ptr, msize_t msize)
-{
-    msize_t		*meta_headers = SMALL_META_HEADER_FOR_PTR(ptr);
-    unsigned		index = SMALL_META_INDEX_FOR_PTR(ptr);
-    size_t		original_size = SMALL_BYTES_FOR_MSIZE(msize);
-    unsigned char	*next_block = ((unsigned char *)ptr + original_size);
-    msize_t		next_index = index + msize;
-    msize_t		previous_msize, next_msize;
-    void		*previous;
-
-    // Assumes locked
-    CHECK_LOCKED(szone, __PRETTY_FUNCTION__);
-#if DEBUG_MALLOC
-    if (LOG(szone,ptr)) {
-	malloc_printf("in small_free_no_lock(), ptr=%p, msize=%d\n", ptr, msize);
-    }
-    if (! msize) {
-	malloc_printf("in small_free_no_lock(), ptr=%p, msize=%d\n", ptr, msize);
-	szone_error(szone, "trying to free small block that is too small", ptr);
-    }
-#endif
-    // We try to coalesce this block with the preceeding one
-    if (index && (SMALL_PREVIOUS_MSIZE(ptr) <= index)) {
-	previous_msize = SMALL_PREVIOUS_MSIZE(ptr);
-	if (meta_headers[index - previous_msize] == (previous_msize | SMALL_IS_FREE)) {
-	    previous = ptr - SMALL_BYTES_FOR_MSIZE(previous_msize);
-	    // previous is really to be coalesced
-#if DEBUG_MALLOC
-	    if (LOG(szone, ptr) || LOG(szone,previous)) { 
-		malloc_printf("in small_free_no_lock(), coalesced backwards for %p previous=%p\n", ptr, previous);
-	    }
-#endif
-	    small_free_list_remove_ptr(szone, previous, previous_msize);
-	    small_meta_header_set_middle(meta_headers, index);
-	    ptr = previous;
-	    msize += previous_msize;
-	    index -= previous_msize;
-	}
-    }
-    // We try to coalesce with the next block
-    if ((next_block < SMALL_REGION_END(*region)) && (meta_headers[next_index] & SMALL_IS_FREE)) {
-	// next block is free, we coalesce
-	next_msize = meta_headers[next_index] & ~ SMALL_IS_FREE;
-#if DEBUG_MALLOC
-	if (LOG(szone,ptr)) malloc_printf("In small_free_no_lock(), for ptr=%p, msize=%d coalesced next block=%p next_msize=%d\n", ptr, msize, next_block, next_msize);
-#endif
-	small_free_list_remove_ptr(szone, next_block, next_msize);
-	small_meta_header_set_middle(meta_headers, next_index);
-	msize += next_msize;
-    }
-    if (szone->debug_flags & SCALABLE_MALLOC_DO_SCRIBBLE) {
-	if (!msize) {
-	    szone_error(szone, "incorrect size information - block header was damaged", ptr);
-	} else {
-	    memset(ptr, 0x55, SMALL_BYTES_FOR_MSIZE(msize));
-	}
-    }
-    small_free_list_add_ptr(szone, ptr, msize);
-    small_meta_header_set_is_free(meta_headers, index, msize);
-    szone->num_small_objects--;
-    szone->num_bytes_in_small_objects -= original_size; // we use original_size and not msize to avoid double counting the coalesced blocks
-}
-
-static void *
-small_malloc_from_region_no_lock(szone_t *szone, msize_t msize)
-{
-    small_region_t	last_region;
-    void		*last_block;
-    void		*ptr;
-    void 		*new_address;
-    msize_t		*meta_headers;
-    msize_t		index ;
-    size_t		region_capacity;
-    msize_t		new_msize;
-    small_region_t	*new_regions;
-    msize_t		msize_left;
-
-    // Allocates from the last region or a freshly allocated region
-    CHECK_LOCKED(szone, __PRETTY_FUNCTION__);
-    // Before anything we transform the small_bytes_free_at_end - if any - to a regular free block
-    if (szone->small_bytes_free_at_end) {
-	last_region = szone->small_regions[szone->num_small_regions - 1];
-	last_block = (void *)(SMALL_REGION_END(last_region) - szone->small_bytes_free_at_end);
-	small_free_list_add_ptr(szone, last_block, SMALL_MSIZE_FOR_BYTES(szone->small_bytes_free_at_end));
-	*SMALL_METADATA_FOR_PTR(last_block) = SMALL_MSIZE_FOR_BYTES(szone->small_bytes_free_at_end) | SMALL_IS_FREE;
-	szone->small_bytes_free_at_end = 0;
-    }
-    // time to create a new region
-    new_address = allocate_pages(szone, SMALL_REGION_SIZE, SMALL_BLOCKS_ALIGN, 0, VM_MAKE_TAG(VM_MEMORY_MALLOC_SMALL));
-    if (!new_address) {
-	// out of memory!
-	return NULL;
-    }
-    ptr = new_address;
-    meta_headers = SMALL_META_HEADER_FOR_PTR(ptr);
-    index = 0;
-    if (szone->num_small_regions == INITIAL_NUM_SMALL_REGIONS) {
-	// time to grow the number of regions
-	region_capacity = (1 << (32 - SMALL_BLOCKS_ALIGN)) - 20; // that is for sure the maximum number of small regions we can have
-	new_msize = (region_capacity * sizeof(small_region_t) + SMALL_QUANTUM - 1) / SMALL_QUANTUM;
-	new_regions = ptr;
-	small_meta_header_set_in_use(meta_headers, index, new_msize);
-	szone->num_small_objects++;
-	szone->num_bytes_in_small_objects += SMALL_BYTES_FOR_MSIZE(new_msize);
-	memcpy(new_regions, szone->small_regions, INITIAL_NUM_SMALL_REGIONS * sizeof(small_region_t));
-	// We intentionally leak the previous regions pointer to avoid multi-threading crashes if
-	// another thread was reading it (unlocked) while we are changing it.
-	szone->small_regions = new_regions; // note we set this pointer after it's all set
-	ptr += SMALL_BYTES_FOR_MSIZE(new_msize);
-	index = new_msize;
-    }
-    szone->small_regions[szone->num_small_regions] = new_address;
-    // we bump the number of regions AFTER we have changes the regions pointer to enable finding a
-    // small region without taking the lock
-    // XXX naive assumption assumes memory ordering coherence between this and other CPUs
-    szone->num_small_regions++;
-    small_meta_header_set_in_use(meta_headers, index, msize);
-    msize_left = NUM_SMALL_BLOCKS - index;
-    szone->num_small_objects++;
-    szone->num_bytes_in_small_objects += SMALL_BYTES_FOR_MSIZE(msize);
-    // add a big free block
-    index += msize; msize_left -= msize;
-    meta_headers[index] = msize_left;
-    szone->small_bytes_free_at_end = SMALL_BYTES_FOR_MSIZE(msize_left);
-    return ptr;
-}
-
-static INLINE boolean_t
-try_realloc_small_in_place(szone_t *szone, void *ptr, size_t old_size, size_t new_size)
-{
-    // returns 1 on success
-    msize_t	*meta_headers = SMALL_META_HEADER_FOR_PTR(ptr);
-    unsigned	index = SMALL_META_INDEX_FOR_PTR(ptr);
-    msize_t	old_msize = SMALL_MSIZE_FOR_BYTES(old_size);
-    msize_t	new_msize = SMALL_MSIZE_FOR_BYTES(new_size + SMALL_QUANTUM - 1);
-    void	*next_block = (char *)ptr + old_size;
-    unsigned	next_index = index + old_msize;
-    msize_t	next_msize_and_free;
-    msize_t	next_msize;
-    msize_t	leftover_msize;
-    void	*leftover;
-    unsigned	leftover_index;
-
-    if (next_index >= NUM_SMALL_BLOCKS) {
-	return 0;
-    }
-#if DEBUG_MALLOC
-    if ((uintptr_t)next_block & (SMALL_QUANTUM - 1)) {
-	szone_error(szone, "internal invariant broken in realloc(next_block)", next_block);
-    }
-    if (meta_headers[index] != old_msize)
-	malloc_printf("*** try_realloc_small_in_place incorrect old %d %d\n",
-	  meta_headers[index], old_msize);
-#endif
-    SZONE_LOCK(szone);
-    /*
-     * Look for a free block immediately afterwards.  If it's large enough, we can consume (part of)
-     * it.
-     */
-    next_msize_and_free = meta_headers[next_index];
-    next_msize = next_msize_and_free & ~ SMALL_IS_FREE;
-    if (!(next_msize_and_free & SMALL_IS_FREE) || (old_msize + next_msize < new_msize)) {
-	SZONE_UNLOCK(szone);
-	return 0;
-    }
-    /*
-     * The following block is big enough; pull it from its freelist and chop off enough to satisfy
-     * our needs.
-     */
-    small_free_list_remove_ptr(szone, next_block, next_msize);
-    small_meta_header_set_middle(meta_headers, next_index);
-    leftover_msize = old_msize + next_msize - new_msize;
-    if (leftover_msize) {
-	/* there's some left, so put the remainder back */
-	leftover = (unsigned char *)ptr + SMALL_BYTES_FOR_MSIZE(new_msize);
-	small_free_list_add_ptr(szone, leftover, leftover_msize);
-	leftover_index = index + new_msize;
-	small_meta_header_set_is_free(meta_headers, leftover_index, leftover_msize);
-    }
-#if DEBUG_MALLOC
-    if (SMALL_BYTES_FOR_MSIZE(new_msize) >= LARGE_THRESHOLD) {
-	malloc_printf("*** realloc in place for %p exceeded msize=%d\n", new_msize);
-    }
-#endif
-    small_meta_header_set_in_use(meta_headers, index, new_msize);
-#if DEBUG_MALLOC
-    if (LOG(szone,ptr)) {
-	malloc_printf("in szone_realloc(), ptr=%p, msize=%d\n", ptr, *SMALL_METADATA_FOR_PTR(ptr));
-    }
-#endif
-    szone->num_bytes_in_small_objects += SMALL_BYTES_FOR_MSIZE(new_msize - old_msize);
-    SZONE_UNLOCK(szone);
-    CHECK(szone, __PRETTY_FUNCTION__);
-    return 1;
-}
-
-static boolean_t
-szone_check_small_region(szone_t *szone, small_region_t *region)
-{
-    unsigned char	*ptr = SMALL_REGION_ADDRESS(*region);
-    msize_t		*meta_headers = SMALL_META_HEADER_FOR_PTR(ptr);
-    unsigned char	*region_end = SMALL_REGION_END(*region);
-    msize_t		prev_free = 0;
-    unsigned		index;
-    msize_t		msize_and_free;
-    msize_t		msize;
-    free_list_t		*free_head;
-    msize_t		*follower;
-
-    CHECK_LOCKED(szone, __PRETTY_FUNCTION__);
-    if (region == szone->small_regions + szone->num_small_regions - 1) region_end -= szone->small_bytes_free_at_end;
-    while (ptr < region_end) {
-	index = SMALL_META_INDEX_FOR_PTR(ptr);
-	msize_and_free = meta_headers[index];
-	if (!(msize_and_free & SMALL_IS_FREE)) {
-	    // block is in use
-	    msize = msize_and_free;
-	    if (!msize) {
-		malloc_printf("*** invariant broken: null msize ptr=%p region#=%d num_small_regions=%d end=%p\n",
-		  ptr, region - szone->small_regions, szone->num_small_regions, (void *)region_end);
-		return 0;
-	    }
-	    if (msize > (LARGE_THRESHOLD / SMALL_QUANTUM)) {
-		malloc_printf("*** invariant broken for %p this small msize=%d - size is too large\n",
-		  ptr, msize_and_free);
-		return 0;
-	    }
-	    ptr += SMALL_BYTES_FOR_MSIZE(msize);
-	    prev_free = 0;
-	} else {
-	    // free pointer
-	    msize = msize_and_free & ~ SMALL_IS_FREE;
-	    free_head = (free_list_t *)ptr;
-	    follower = (msize_t *)FOLLOWING_SMALL_PTR(ptr, msize);
-	    if (!msize) {
-		malloc_printf("*** invariant broken for free block %p this msize=%d\n", ptr, msize);
-		return 0;
-	    }
-	    if (prev_free) {
-		malloc_printf("*** invariant broken for %p (2 free in a row)\n", ptr);
-		return 0;
-	    }
-	    free_list_checksum(szone, free_head, __PRETTY_FUNCTION__);
-	    if (free_head->previous && !SMALL_PTR_IS_FREE(free_head->previous)) {
-		malloc_printf("*** invariant broken for %p (previous %p is not a free pointer)\n",
-		  ptr, free_head->previous);
-		return 0;
-	    }
-	    if (free_head->next && !SMALL_PTR_IS_FREE(free_head->next)) {
-		malloc_printf("*** invariant broken for %p (next is not a free pointer)\n", ptr);
-		return 0;
-	    }
-	    if (SMALL_PREVIOUS_MSIZE(follower) != msize) {
-		malloc_printf("*** invariant broken for small free %p followed by %p in region [%p-%p] "
-		  "(end marker incorrect) should be %d; in fact %d\n",
-		  ptr, follower, SMALL_REGION_ADDRESS(*region), region_end, msize, SMALL_PREVIOUS_MSIZE(follower));
-		return 0;
-	    }
-	    ptr = (unsigned char *)follower;
-	    prev_free = SMALL_IS_FREE;
-	}
-    }
-    return 1;
-}
-
-static kern_return_t
-small_in_use_enumerator(task_t task, void *context, unsigned type_mask, vm_address_t region_address, unsigned short num_regions, size_t small_bytes_free_at_end, memory_reader_t reader, vm_range_recorder_t recorder)
-{
-    small_region_t	*regions;
-    unsigned		index = 0;
-    vm_range_t		buffer[MAX_RECORDER_BUFFER];
-    unsigned		count = 0;
-    kern_return_t	err;
-    small_region_t	region;
-    vm_range_t		range;
-    vm_range_t		admin_range;
-    vm_range_t		ptr_range;
-    unsigned char	*mapped_region;
-    msize_t		*block_header;
-    unsigned		block_index;
-    unsigned		block_limit;
-    msize_t		msize_and_free;
-    msize_t		msize;
-
-    err = reader(task, region_address, sizeof(small_region_t) * num_regions, (void **)&regions);
-    if (err) return err;
-    while (index < num_regions) {
-	region = regions[index];
-	range.address = (vm_address_t)SMALL_REGION_ADDRESS(region);
-	range.size = SMALL_REGION_SIZE;
-	if (type_mask & MALLOC_ADMIN_REGION_RANGE_TYPE) {
-	    admin_range.address = range.address + (1 << SMALL_BLOCKS_ALIGN);
-	    admin_range.size = range.size - (1 << SMALL_BLOCKS_ALIGN);
-	    recorder(task, context, MALLOC_ADMIN_REGION_RANGE_TYPE, &admin_range, 1);
-	}
-	if (type_mask & (MALLOC_PTR_REGION_RANGE_TYPE | MALLOC_ADMIN_REGION_RANGE_TYPE)) {
-	    ptr_range.address = range.address;
-	    ptr_range.size = 1 << SMALL_BLOCKS_ALIGN;
-	    recorder(task, context, MALLOC_PTR_REGION_RANGE_TYPE, &ptr_range, 1);
-	}
-	if (type_mask & MALLOC_PTR_IN_USE_RANGE_TYPE) {
-	    err = reader(task, range.address, range.size, (void **)&mapped_region);
-	    if (err) return err;
-	    block_header = (msize_t *)(mapped_region + (1 << SMALL_BLOCKS_ALIGN));
-	    block_index = 0;
-	    block_limit = NUM_SMALL_BLOCKS;
-	    if (index == num_regions - 1)
-		block_limit -= SMALL_MSIZE_FOR_BYTES(small_bytes_free_at_end);
-	    while (block_index < block_limit) {
-		msize_and_free = block_header[block_index];
-		msize = msize_and_free & ~ SMALL_IS_FREE;
-		if (! (msize_and_free & SMALL_IS_FREE)) {
-		    // Block in use
-		    buffer[count].address = range.address + SMALL_BYTES_FOR_MSIZE(block_index);
-		    buffer[count].size = SMALL_BYTES_FOR_MSIZE(msize);
-		    count++;
-		    if (count >= MAX_RECORDER_BUFFER) {
-			recorder(task, context, MALLOC_PTR_IN_USE_RANGE_TYPE, buffer, count);
-			count = 0;
-		    }
-		}
-		block_index += msize;
-	    }
-	}
-	index++;
-    }
-    if (count) {
-	recorder(task, context, MALLOC_PTR_IN_USE_RANGE_TYPE, buffer, count);
-    }
-    return 0;
-}
-
-static INLINE void *
-small_malloc_from_free_list(szone_t *szone, msize_t msize)
-{
-    grain_t	grain = (msize <= NUM_SMALL_SLOTS) ? msize - 1 : NUM_SMALL_SLOTS - 1;
-    unsigned	bitmap = szone->small_bitmap & ~ ((1 << grain) - 1);
-    void	*ptr;
-    msize_t	this_msize;
-    free_list_t	**free_list;
-    free_list_t	**limit;
-    free_list_t	*next;
-    msize_t	leftover_msize;
-    void	*leftover_ptr;
-    msize_t	*meta_headers;
-    unsigned	leftover_index;
-
-    // Assumes locked
-    CHECK_LOCKED(szone, __PRETTY_FUNCTION__);
-    
-    if (!bitmap) goto try_small_from_end;
-    grain = BITMAP32_FFS(bitmap) - 1;
-    // first try the small grains
-    limit = szone->small_free_list + NUM_SMALL_SLOTS - 1;
-    free_list = szone->small_free_list + grain;
-    while (free_list < limit) {
-	// try bigger grains
-	ptr = *free_list;
-	if (ptr) {
-	    next = ((free_list_t *)ptr)->next;
-	    if (next) {
-		next->previous = NULL;
-		free_list_set_checksum(szone, next);
-	    }
-	    *free_list = next;
-	    this_msize = SMALL_PTR_SIZE(ptr);
-	    goto add_leftover_and_proceed;
-	}
-	free_list++;
-    }
-    // We now check the large grains for one that is big enough
-    ptr = *free_list;
-    while (ptr) {
-	this_msize = SMALL_PTR_SIZE(ptr);
-	if (this_msize >= msize) {
-	    small_free_list_remove_ptr(szone, ptr, this_msize);
-	    goto add_leftover_and_proceed;
-	}
-	ptr = ((free_list_t *)ptr)->next;
-    }
-try_small_from_end:
-    // Let's see if we can use szone->small_bytes_free_at_end
-    if (szone->small_bytes_free_at_end >= SMALL_BYTES_FOR_MSIZE(msize)) {
-	ptr = (void *)(SMALL_REGION_END(szone->small_regions[szone->num_small_regions-1]) - szone->small_bytes_free_at_end);
-	szone->small_bytes_free_at_end -= SMALL_BYTES_FOR_MSIZE(msize);
-	if (szone->small_bytes_free_at_end) {
-	    // let's mark this block as in use to serve as boundary
-	    *SMALL_METADATA_FOR_PTR(ptr + SMALL_BYTES_FOR_MSIZE(msize)) = SMALL_MSIZE_FOR_BYTES(szone->small_bytes_free_at_end);
-	}
-	this_msize = msize;
-	goto return_small_alloc;
-    }
-    return NULL;
-add_leftover_and_proceed:
-    if (this_msize > msize) {
-	leftover_msize = this_msize - msize;
-	leftover_ptr = ptr + SMALL_BYTES_FOR_MSIZE(msize);
-#if DEBUG_MALLOC
-	if (LOG(szone,ptr)) {
-	    malloc_printf("in small_malloc_from_free_list(), adding leftover ptr=%p, this_msize=%d\n", ptr, this_msize);
-	}
-#endif
-	small_free_list_add_ptr(szone, leftover_ptr, leftover_msize);
-	meta_headers = SMALL_META_HEADER_FOR_PTR(leftover_ptr);
-	leftover_index = SMALL_META_INDEX_FOR_PTR(leftover_ptr);
-	small_meta_header_set_is_free(meta_headers, leftover_index, leftover_msize);
-	this_msize = msize;
-    }
-return_small_alloc:
-    szone->num_small_objects++;
-    szone->num_bytes_in_small_objects += SMALL_BYTES_FOR_MSIZE(this_msize);
-#if DEBUG_MALLOC
-    if (LOG(szone,ptr)) {
-	malloc_printf("in small_malloc_from_free_list(), ptr=%p, this_msize=%d, msize=%d\n", ptr, this_msize, msize);
-    }
-#endif
-    *SMALL_METADATA_FOR_PTR(ptr) = this_msize;
-    return ptr;
-}
-
-static INLINE void *
-small_malloc_should_clear(szone_t *szone, msize_t msize, boolean_t cleared_requested)
-{
-    boolean_t	locked = 0;
-#if SMALL_CACHE
-    void	*ptr;
-#endif
-    
-#if SMALL_CACHE
-    ptr = (void *)szone->last_small_free;
-    if ((((uintptr_t)ptr) & (SMALL_QUANTUM - 1)) == msize) {
-	// we have a candidate - let's lock to make sure
-	LOCK_AND_NOTE_LOCKED(szone, locked);
-	if (ptr == (void *)szone->last_small_free) {
-	    szone->last_small_free = NULL;
-	    SZONE_UNLOCK(szone);
-	    CHECK(szone, __PRETTY_FUNCTION__);
-	    ptr = (void *)((uintptr_t)ptr & ~ (SMALL_QUANTUM - 1));
-	    if (cleared_requested) {
-		memset(ptr, 0, SMALL_BYTES_FOR_MSIZE(msize));
-	    }
-	    return ptr;
-	}
-    }
-#endif
-    // Except in rare occasions where we need to add a new region, we are going to end up locking,
-    // so we might as well lock right away to avoid doing unnecessary optimistic probes
-    if (!locked) LOCK_AND_NOTE_LOCKED(szone, locked);
-    ptr = small_malloc_from_free_list(szone, msize);
-    if (ptr) {
-	SZONE_UNLOCK(szone);
-	CHECK(szone, __PRETTY_FUNCTION__);
-	if (cleared_requested) {
-	    memset(ptr, 0, SMALL_BYTES_FOR_MSIZE(msize));
-	}
-	return ptr;
-    }
-    ptr = small_malloc_from_region_no_lock(szone, msize);
-    // we don't clear because this freshly allocated space is pristine
-    SZONE_UNLOCK(szone);
-    CHECK(szone, __PRETTY_FUNCTION__);
-    return ptr;
-}
-
-// tries to allocate a small, cleared block
-static INLINE void *
-small_malloc_cleared_no_lock(szone_t *szone, msize_t msize)
-{
-    void	*ptr;
-
-    // Assumes already locked
-    CHECK_LOCKED(szone, __PRETTY_FUNCTION__);
-    ptr = small_malloc_from_free_list(szone, msize);
-    if (ptr) {
-	memset(ptr, 0, SMALL_BYTES_FOR_MSIZE(msize));
-	return ptr;
-    } else {
-	ptr = small_malloc_from_region_no_lock(szone, msize);
-	// we don't clear because this freshly allocated space is pristine
-    }
-    return ptr;
-}
-
-static INLINE void
-free_small(szone_t *szone, void *ptr, small_region_t *small_region)
-{
-    msize_t		msize_and_free;
-#if SMALL_CACHE
-    void		*ptr2;
-#endif
-    
-    // ptr is known to be in small_region
-    msize_and_free = *SMALL_METADATA_FOR_PTR(ptr);
-    if (msize_and_free & SMALL_IS_FREE) {
-	szone_error(szone, "Object already freed being freed", ptr);
-	return;
-    }
-    CHECK(szone, __PRETTY_FUNCTION__);
-    SZONE_LOCK(szone);
-#if SMALL_CACHE
-    ptr2 = szone->last_small_free;
-    szone->last_small_free = (void *)(((uintptr_t)ptr) | msize_and_free);
-    if (!ptr2) {
-	SZONE_UNLOCK(szone);
-	CHECK(szone, __PRETTY_FUNCTION__);
-	return;
-    }
-    msize_and_free = (uintptr_t)ptr2 & (SMALL_QUANTUM - 1);
-    ptr = (void *)(((uintptr_t)ptr2) & ~ (SMALL_QUANTUM - 1));
-    small_region = small_region_for_ptr_no_lock(szone, ptr);
-    if (!small_region) {
-	szone_error(szone, "double free (small cache)", ptr);
-	return;
-    }
-#endif
-    small_free_no_lock(szone, small_region, ptr, msize_and_free);
-    SZONE_UNLOCK(szone);
-    CHECK(szone, __PRETTY_FUNCTION__);
-}
-
-static void
-print_small_free_list(szone_t *szone)
-{
-    grain_t		grain = 0;
-    free_list_t		*ptr;
-    
-    malloc_printf("small free sizes: ");
-    while (grain < NUM_SMALL_SLOTS) {
-	ptr = szone->small_free_list[grain];
-	if (ptr) {
-	    malloc_printf("%s%y[%d]; ", (grain == NUM_SMALL_SLOTS-1) ? ">=" : "", (grain + 1) * SMALL_QUANTUM, free_list_count(ptr));
-	}
-	grain++;
-    }
-    malloc_printf("\n");
-}
-
-static void
-print_small_region(szone_t *szone, boolean_t verbose, small_region_t *region, size_t bytes_at_end)
-{
-    unsigned		counts[1024];
-    unsigned		in_use = 0;
-    void		*start = SMALL_REGION_ADDRESS(*region);
-    void		*limit = SMALL_REGION_END(*region) - bytes_at_end;
-    msize_t		msize_and_free;
-    msize_t		msize;
-    unsigned		ci;
-
-    memset(counts, 0, 1024 * sizeof(unsigned));
-    while (start < limit) {
-	msize_and_free = *SMALL_METADATA_FOR_PTR(start);
-	msize = msize_and_free & ~ SMALL_IS_FREE;
-	if (!(msize_and_free & SMALL_IS_FREE)) {
-	    // block in use
-	    if (msize < 1024)
-		counts[msize]++;
-	    in_use++;
-	}
-	start += SMALL_BYTES_FOR_MSIZE(msize);
-    }
-    malloc_printf("Small region [%p-%p, %y]\tIn_use=%d ",
-      SMALL_REGION_ADDRESS(*region), SMALL_REGION_END(*region), (int)SMALL_REGION_SIZE, in_use);
-    if (bytes_at_end)
-	malloc_printf("Untouched=%y ", bytes_at_end);
-    if (verbose && in_use) {
-	malloc_printf("\n\tSizes in use: "); 
-	for (ci = 0; ci < 1024; ci++)
-	    if (counts[ci])
-		malloc_printf("%d[%d] ", SMALL_BYTES_FOR_MSIZE(ci), counts[ci]);
-    }
-    malloc_printf("\n");
-}
-
-static boolean_t
-small_free_list_check(szone_t *szone, grain_t grain)
-{
-    unsigned	count = 0;
-    free_list_t	*ptr = szone->small_free_list[grain];
-    free_list_t	*previous = NULL;
-    msize_t	msize_and_free;
-
-    CHECK_LOCKED(szone, __PRETTY_FUNCTION__);
-    while (ptr) {
-	msize_and_free = *SMALL_METADATA_FOR_PTR(ptr);
-	count++;
-	if (!(msize_and_free & SMALL_IS_FREE)) {
-	    malloc_printf("*** in-use ptr in free list grain=%d count=%d ptr=%p\n", grain, count, ptr);
-	    return 0;
-	}
-	if (((uintptr_t)ptr) & (SMALL_QUANTUM - 1)) {
-	    malloc_printf("*** unaligned ptr in free list grain=%d  count=%d ptr=%p\n", grain, count, ptr);
-	    return 0;
-	}
-	if (!small_region_for_ptr_no_lock(szone, ptr)) {
-	    malloc_printf("*** ptr not in szone grain=%d  count=%d ptr=%p\n", grain, count, ptr);
-	    return 0;
-	}
-	free_list_checksum(szone, ptr, __PRETTY_FUNCTION__);
-	if (ptr->previous != previous) {
-	    malloc_printf("*** previous incorrectly set grain=%d  count=%d ptr=%p\n", grain, count, ptr);
-	    return 0;
-	}
-	previous = ptr;
-	ptr = ptr->next;
-    }
-    return 1;
-}
-
-/*********************	LARGE ENTRY UTILITIES	************************/
-
-#if DEBUG_MALLOC
-
-static void
-large_debug_print(szone_t *szone)
-{
-    unsigned		num_large_entries = szone->num_large_entries;
-    unsigned		index = num_large_entries;
-    large_entry_t	*range;
-
-    for (index = 0, range = szone->large_entries; index < szone->num_large_entries; index++, range++)
-	if (!LARGE_ENTRY_IS_EMPTY(*range))
-	    malloc_printf("%d: %p(%y);  ", index, LARGE_ENTRY_ADDRESS(*range), LARGE_ENTRY_SIZE(*range));
-
-    malloc_printf("\n");
-}
-#endif
-
-/*
- * Scan the hash ring looking for an entry for the given pointer.
- */
-static large_entry_t *
-large_entry_for_pointer_no_lock(szone_t *szone, const void *ptr)
-{
-    // result only valid with lock held
-    unsigned		num_large_entries = szone->num_large_entries;
-    unsigned		hash_index;
-    unsigned		index;
-    large_entry_t	*range;
-
-    if (!num_large_entries)
-	return NULL;
-    hash_index = ((uintptr_t)ptr >> vm_page_shift) % num_large_entries;
-    index = hash_index;
-    do {
-	range = szone->large_entries + index;
-	if (LARGE_ENTRY_MATCHES(*range, ptr))
-	    return range;
-	if (LARGE_ENTRY_IS_EMPTY(*range))
-	    return NULL; // end of chain
-	index++;
-	if (index == num_large_entries)
-	    index = 0;
-    } while (index != hash_index);
-    return NULL;
-}
-
-static void
-large_entry_insert_no_lock(szone_t *szone, large_entry_t range)
-{
-    unsigned		num_large_entries = szone->num_large_entries;
-    unsigned		hash_index = (range.address_and_num_pages >> vm_page_shift) % num_large_entries;
-    unsigned		index = hash_index;
-    large_entry_t	*entry;
-
-    do {
-	entry = szone->large_entries + index;
-	if (LARGE_ENTRY_IS_EMPTY(*entry)) {
-	    *entry = range;
-	    return; // end of chain
-	}
-	index++;
-	if (index == num_large_entries)
-	    index = 0;
-    } while (index != hash_index);
-}
-
-static INLINE void
-large_entries_rehash_after_entry_no_lock(szone_t *szone, large_entry_t *entry)
-{
-    unsigned		num_large_entries = szone->num_large_entries;
-    unsigned		hash_index = entry - szone->large_entries;
-    unsigned		index = hash_index;
-    large_entry_t	range;
-
-    do {
-	index++;
-	if (index == num_large_entries)
-	    index = 0;
-	range = szone->large_entries[index];
-	if (LARGE_ENTRY_IS_EMPTY(range))
-	    return;
-	szone->large_entries[index].address_and_num_pages = 0;
-	large_entry_insert_no_lock(szone, range); // this will reinsert in the
-						  // proper place
-    } while (index != hash_index);
-}
-
-static INLINE large_entry_t *
-large_entries_alloc_no_lock(szone_t *szone, unsigned num)
-{
-    size_t	size = num * sizeof(large_entry_t);
-    boolean_t	is_vm_allocation = size >= LARGE_THRESHOLD;
-
-    if (is_vm_allocation) {
-	// Note that we allocate memory (via a system call) under a spin lock
-	// That is certainly evil, however it's very rare in the lifetime of a process
-	// The alternative would slow down the normal case
-	return (void *)allocate_pages(szone, round_page(size), 0, 0, VM_MAKE_TAG(VM_MEMORY_MALLOC_LARGE));
-    } else {
-	return small_malloc_cleared_no_lock(szone, SMALL_MSIZE_FOR_BYTES(size + SMALL_QUANTUM - 1));
-    }
-}
-
-static void
-large_entries_free_no_lock(szone_t *szone, large_entry_t *entries, unsigned num, vm_range_t *range_to_deallocate)
-{
-    // returns range to deallocate
-    size_t		size = num * sizeof(large_entry_t);
-    boolean_t		is_vm_allocation = size >= LARGE_THRESHOLD;
-    small_region_t	*region;
-    msize_t		msize_and_free;
-    
-    if (is_vm_allocation) {
-	range_to_deallocate->address = (vm_address_t)entries;
-	range_to_deallocate->size = round_page(size);
-    } else {
-	range_to_deallocate->size = 0;
-	region = small_region_for_ptr_no_lock(szone, entries);
-	msize_and_free = *SMALL_METADATA_FOR_PTR(entries);
-	if (msize_and_free & SMALL_IS_FREE) {
-	    szone_error(szone, "object already freed being freed", entries);
-	    return;
-	}
-	small_free_no_lock(szone, region, entries, msize_and_free);
-    }
-}
-
-static void
-large_entries_grow_no_lock(szone_t *szone, vm_range_t *range_to_deallocate)
-{
-    // sets range_to_deallocate
-    unsigned		old_num_entries = szone->num_large_entries;
-    large_entry_t	*old_entries = szone->large_entries;
-    unsigned		new_num_entries = (old_num_entries) ? old_num_entries * 2 + 1 : 63; // always an odd number for good hashing
-    large_entry_t	*new_entries = large_entries_alloc_no_lock(szone, new_num_entries);
-    unsigned		index = old_num_entries;
-    large_entry_t	oldRange;
-
-    szone->num_large_entries = new_num_entries;
-    szone->large_entries = new_entries;
-
-    /* rehash entries into the new list */
-    while (index--) {
-	oldRange = old_entries[index];
-	if (!LARGE_ENTRY_IS_EMPTY(oldRange)) {
-	    large_entry_insert_no_lock(szone, oldRange);
-	}
-    }
-    if (old_entries) {
-	large_entries_free_no_lock(szone, old_entries, old_num_entries, range_to_deallocate);
-    } else {
-	range_to_deallocate->size = 0;
-    }
-}
-
-// frees the specific entry in the size table
-// returns a range to truly deallocate
-static vm_range_t
-large_free_no_lock(szone_t *szone, large_entry_t *entry)
-{
-    vm_range_t		range;
-    
-    range.address = (vm_address_t)LARGE_ENTRY_ADDRESS(*entry);
-    range.size = (vm_size_t)LARGE_ENTRY_SIZE(*entry);
-    szone->num_large_objects_in_use--;
-    szone->num_bytes_in_large_objects -= range.size;
-    if (szone->debug_flags & SCALABLE_MALLOC_ADD_GUARD_PAGES) {
-	protect(szone, (void *)range.address, range.size, VM_PROT_READ | VM_PROT_WRITE, szone->debug_flags);
-	range.address -= vm_page_size;
-	range.size += 2 * vm_page_size;
-    }
-    entry->address_and_num_pages = 0;
-    large_entries_rehash_after_entry_no_lock(szone, entry);
-#if DEBUG_MALLOC
-    if (large_entry_for_pointer_no_lock(szone, (void *)range.address)) {
-	malloc_printf("*** freed entry %p still in use; num_large_entries=%d\n",
-	  range.address, szone->num_large_entries);
-	large_debug_print(szone);
-	szone_sleep();
-    }
-#endif
-    return range;
-}
-
-static kern_return_t
-large_in_use_enumerator(task_t task, void *context, unsigned type_mask, vm_address_t large_entries_address, unsigned num_entries, memory_reader_t reader, vm_range_recorder_t recorder)
-{
-    unsigned		index = 0;
-    vm_range_t		buffer[MAX_RECORDER_BUFFER];
-    unsigned		count = 0;
-    large_entry_t	*entries;
-    kern_return_t	err;
-    vm_range_t		range;
-    large_entry_t	entry;
-
-    err = reader(task, large_entries_address, sizeof(large_entry_t) * num_entries, (void **)&entries);
-    if (err)
-	return err;
-    index = num_entries;
-    if ((type_mask & MALLOC_ADMIN_REGION_RANGE_TYPE) &&
-      (num_entries * sizeof(large_entry_t) >= LARGE_THRESHOLD)) {
-	range.address = large_entries_address;
-	range.size = round_page(num_entries * sizeof(large_entry_t));
-	recorder(task, context, MALLOC_ADMIN_REGION_RANGE_TYPE, &range, 1);
-    }
-    if (type_mask & (MALLOC_PTR_IN_USE_RANGE_TYPE | MALLOC_PTR_REGION_RANGE_TYPE))
-	while (index--) {
-	    entry = entries[index];
-	    if (!LARGE_ENTRY_IS_EMPTY(entry)) {
-		range.address = (vm_address_t)LARGE_ENTRY_ADDRESS(entry);
-		range.size = (vm_size_t)LARGE_ENTRY_SIZE(entry);
-		buffer[count++] = range;
-		if (count >= MAX_RECORDER_BUFFER) {
-		    recorder(task, context, MALLOC_PTR_IN_USE_RANGE_TYPE | MALLOC_PTR_REGION_RANGE_TYPE, buffer, count);
-		    count = 0;
-		}
-	    }
-	}
-    if (count) {
-	recorder(task, context, MALLOC_PTR_IN_USE_RANGE_TYPE
-	  | MALLOC_PTR_REGION_RANGE_TYPE, buffer, count);
-    }
-    return 0;
-}
-
-/*********************	HUGE ENTRY UTILITIES	************************/
-
-static huge_entry_t *
-huge_entry_for_pointer_no_lock(szone_t *szone, const void *ptr)
-{
-    unsigned		index;
-    huge_entry_t	*huge;
-
-    for (index = szone->num_huge_entries, huge = szone->huge_entries;
-	 index > 0;
-	 index--, huge++) {
-    
-	if ((void *)huge->address == ptr)
-	    return huge;
-    }
-    return NULL;
-}
-
-static boolean_t
-huge_entry_append(szone_t *szone, huge_entry_t huge)
-{
-    huge_entry_t	*new_huge_entries = NULL, *old_huge_entries;
-    unsigned		num_huge_entries;
-    
-    // We do a little dance with locking because doing allocation (even in the
-    // default szone) may cause something to get freed in this szone, with a
-    // deadlock
-    // Returns 1 on success
-    SZONE_LOCK(szone);
-    for (;;) {
-	num_huge_entries = szone->num_huge_entries;
-	SZONE_UNLOCK(szone);
-	/* check for counter wrap */
-	if ((num_huge_entries + 1) < num_huge_entries)
-		return 0;
-	/* stale allocation from last time around the loop? */
-	if (new_huge_entries)
-	    szone_free(szone, new_huge_entries);
-	new_huge_entries = szone_malloc(szone, (num_huge_entries + 1) * sizeof(huge_entry_t));
-	if (new_huge_entries == NULL)
-	    return 0;
-	SZONE_LOCK(szone);
-	if (num_huge_entries == szone->num_huge_entries) {
-	    // No change - our malloc still applies
-	    old_huge_entries = szone->huge_entries;
-	    if (num_huge_entries) {
-		memcpy(new_huge_entries, old_huge_entries, num_huge_entries * sizeof(huge_entry_t));
-	    }
-	    new_huge_entries[szone->num_huge_entries++] = huge;
-	    szone->huge_entries = new_huge_entries;
-	    SZONE_UNLOCK(szone);
-	    szone_free(szone, old_huge_entries);
-	    return 1;
-	}
-	// try again!
-    }
-}
-
-static kern_return_t
-huge_in_use_enumerator(task_t task, void *context, unsigned type_mask, vm_address_t huge_entries_address, unsigned num_entries, memory_reader_t reader, vm_range_recorder_t recorder)
-{
-    huge_entry_t	*entries;
-    kern_return_t	err;
-    
-    err = reader(task, huge_entries_address, sizeof(huge_entry_t) * num_entries, (void **)&entries);
-    if (err)
-	return err;
-    if (num_entries)
-	recorder(task, context, MALLOC_PTR_IN_USE_RANGE_TYPE | MALLOC_PTR_REGION_RANGE_TYPE, entries, num_entries);
-
-    return 0;
-}
-
-static void *
-large_and_huge_malloc(szone_t *szone, unsigned num_pages)
-{
-    void		*addr;
-    vm_range_t		range_to_deallocate;
-    huge_entry_t	huge_entry;
-    size_t		size;
-    large_entry_t	large_entry;
-    
-    if (!num_pages)
-	    num_pages = 1; // minimal allocation size for this szone
-    size = (size_t)num_pages << vm_page_shift;
-    range_to_deallocate.size = 0;
-    if (num_pages >= (1 << vm_page_shift)) {
-	addr = allocate_pages(szone, size, 0, szone->debug_flags, VM_MAKE_TAG(VM_MEMORY_MALLOC_HUGE));
-	if (addr == NULL)
-	    return NULL;
-	huge_entry.size = size;
-	huge_entry.address = (vm_address_t)addr;
-	if (!huge_entry_append(szone, huge_entry))
-	    return NULL;	// we are leaking the allocation here
-	SZONE_LOCK(szone);
-	szone->num_bytes_in_huge_objects += size;
-    } else {
-
-	addr = allocate_pages(szone, size, 0, szone->debug_flags, VM_MAKE_TAG(VM_MEMORY_MALLOC_LARGE));
-#if DEBUG_MALLOC
-	if (LOG(szone, addr))
-	    malloc_printf("in szone_malloc true large allocation at %p for %y\n", (void *)addr, size);
-#endif
-	SZONE_LOCK(szone);
-	if (addr == NULL) {
-	    SZONE_UNLOCK(szone);
-	    return NULL;
-	}
-#if DEBUG_MALLOC
-	if (large_entry_for_pointer_no_lock(szone, addr)) {
-	    malloc_printf("freshly allocated is already in use: %p\n", addr);
-	    large_debug_print(szone);
-	    szone_sleep();
-	}
-#endif
-	if ((szone->num_large_objects_in_use + 1) * 4 > szone->num_large_entries) {
-	    // density of hash table too high; grow table
-	    // we do that under lock to avoid a race
-	    large_entries_grow_no_lock(szone, &range_to_deallocate);
-	}
-	large_entry.address_and_num_pages = (uintptr_t)addr | num_pages;
-#if DEBUG_MALLOC
-	if (large_entry_for_pointer_no_lock(szone, addr)) {
-	    malloc_printf("entry about to be added already in use: %p\n", addr);
-	    large_debug_print(szone);
-	    szone_sleep();
-	}
-#endif
-	large_entry_insert_no_lock(szone, large_entry);
-#if DEBUG_MALLOC
-	if (!large_entry_for_pointer_no_lock(szone, (void *)addr)) {
-	    malloc_printf("can't find entry just added\n");
-	    large_debug_print(szone);
-	    szone_sleep();
-	}
-#endif
-	szone->num_large_objects_in_use ++;
-	szone->num_bytes_in_large_objects += size;
-    }
-    SZONE_UNLOCK(szone);
-    if (range_to_deallocate.size) {
-	deallocate_pages(szone, (void *)range_to_deallocate.address, range_to_deallocate.size, 0); // we deallocate outside the lock
-    }
-    return (void *)addr;
-}
-
-static INLINE void
-free_large_or_huge(szone_t *szone, void *ptr)
-{
-    // We have established ptr is page-aligned and not tiny nor small
-    large_entry_t	*entry;
-    vm_range_t		vm_range_to_deallocate;
-    huge_entry_t	*huge;
-    
-    SZONE_LOCK(szone);
-    entry = large_entry_for_pointer_no_lock(szone, ptr);
-    if (entry) {
-	vm_range_to_deallocate = large_free_no_lock(szone, entry);
-#if DEBUG_MALLOC
-	if (large_entry_for_pointer_no_lock(szone, ptr)) {
-	    malloc_printf("*** just after freeing %p still in use num_large_entries=%d\n", ptr, szone->num_large_entries);
-	    large_debug_print(szone);
-	    szone_sleep();
-	}
-#endif
-    } else if ((huge = huge_entry_for_pointer_no_lock(szone, ptr))) {
-	vm_range_to_deallocate = *huge;
-	*huge = szone->huge_entries[--szone->num_huge_entries]; // last entry fills that spot
-	szone->num_bytes_in_huge_objects -= (size_t)vm_range_to_deallocate.size;
-    } else {
-#if DEBUG_MALLOC
-	large_debug_print(szone);
-#endif
-	szone_error(szone, "pointer being freed was not allocated", ptr);
-	return;
-    }
-    SZONE_UNLOCK(szone); // we release the lock asap
-    CHECK(szone, __PRETTY_FUNCTION__);
-    // we deallocate_pages, including guard pages
-    if (vm_range_to_deallocate.address) {
-#if DEBUG_MALLOC
-	if (large_entry_for_pointer_no_lock(szone, (void *)vm_range_to_deallocate.address)) {
-	    malloc_printf("*** invariant broken: %p still in use num_large_entries=%d\n", vm_range_to_deallocate.address, szone->num_large_entries);
-	    large_debug_print(szone);
-	    szone_sleep();
-	}
-#endif
-	deallocate_pages(szone, (void *)vm_range_to_deallocate.address, (size_t)vm_range_to_deallocate.size, 0);
-    }
-}
-
-static INLINE int
-try_realloc_large_or_huge_in_place(szone_t *szone, void *ptr, size_t old_size, size_t new_size)
-{
-    vm_address_t	addr = (vm_address_t)ptr + old_size;
-    large_entry_t	*large_entry, saved_entry;
-    huge_entry_t	*huge_entry, huge;
-    kern_return_t	err;
-
-#if DEBUG_MALLOC
-    if (old_size != ((old_size >> vm_page_shift) << vm_page_shift)) {
-	malloc_printf("*** old_size is %d\n", old_size);
-    }
-#endif
-    SZONE_LOCK(szone);
-    large_entry = large_entry_for_pointer_no_lock(szone, (void *)addr);
-    SZONE_UNLOCK(szone);
-    if (large_entry) {
-	return 0; // large pointer already exists in table - extension is not going to work
-    }
-    new_size = round_page(new_size);
-    /*
-     * Ask for allocation at a specific address, and mark as realloc
-     * to request coalescing with previous realloc'ed extensions.
-     */
-    err = vm_allocate(mach_task_self(), &addr, new_size - old_size, VM_MAKE_TAG(VM_MEMORY_REALLOC));
-    if (err != KERN_SUCCESS) {
-	return 0;
-    }
-    SZONE_LOCK(szone);
-    /*
-     * If the new size is still under the large/huge threshold, we can just
-     * extend the existing large block.
-     *
-     * Note: this logic is predicated on the understanding that an allocated
-     * block can never really shrink, so that the new size will always be 
-     * larger than the old size.
-     *
-     * Note: the use of 1 << vm_page_shift here has to do with the subdivision
-     * of the bits in the large_entry_t, and not the size of a page (directly).
-     */
-    if ((new_size >> vm_page_shift) < (1 << vm_page_shift)) {
-	/* extend existing large entry */
-	large_entry = large_entry_for_pointer_no_lock(szone, ptr);
-	if (!large_entry) {
-	    szone_error(szone, "large entry reallocated is not properly in table", ptr);
-	    /* XXX will cause fault on next reference to entry */
-	}
-	large_entry->address_and_num_pages = (uintptr_t)ptr | (new_size >> vm_page_shift);
-	szone->num_bytes_in_large_objects += new_size - old_size;
-    } else if ((old_size >> vm_page_shift) >= (1 << vm_page_shift)) {
-	/* extend existing huge entry */
-	huge_entry = huge_entry_for_pointer_no_lock(szone, ptr);
-	if (!huge_entry) {
-	    szone_error(szone, "huge entry reallocated is not properly in table", ptr);
-	    /* XXX will cause fault on next reference to huge_entry */
-	}
-	huge_entry->size = new_size;
-	szone->num_bytes_in_huge_objects += new_size - old_size;
-    } else {
-	/* need to convert large entry to huge entry */
-
-	/* release large entry, note we still have the VM allocation */
-	large_entry = large_entry_for_pointer_no_lock(szone, ptr);
-	saved_entry = *large_entry; // in case we need to put it back
-	large_free_no_lock(szone, large_entry);
-	szone->num_bytes_in_large_objects -= old_size;
-
-	/* and get a huge entry */
-	huge.address = (vm_address_t)ptr;
-	huge.size = new_size;	/* fix up size */
-	SZONE_UNLOCK(szone);
-	if (huge_entry_append(szone, huge)) {
-	    szone->num_bytes_in_huge_objects += new_size;
-	    return 1; // success!
-	}
-	SZONE_LOCK(szone);
-	// we leak memory (the extra space appended) but data structures are correct
-	large_entry_insert_no_lock(szone, saved_entry); // this will reinsert the large entry
-    }
-    SZONE_UNLOCK(szone); // we release the lock asap
-    return 1;
-}
-
-/*********************	Zone call backs	************************/
-
-static void
-szone_free(szone_t *szone, void *ptr)
-{
-    tiny_region_t	*tiny_region;
-    small_region_t	*small_region;
-
-#if DEBUG_MALLOC
-    if (LOG(szone, ptr))
-	malloc_printf("in szone_free with %p\n", ptr);
-#endif
-    if (!ptr)
-	return;
-    /*
-     * Try to free to a tiny region.
-     */
-    if ((uintptr_t)ptr & (TINY_QUANTUM - 1)) {
-	szone_error(szone, "Non-aligned pointer being freed", ptr);
-	return;
-    }
-    if ((tiny_region = tiny_region_for_ptr_no_lock(szone, ptr)) != NULL) {
-	free_tiny(szone, ptr, tiny_region);
-	return;
-    }
-
-    /*
-     * Try to free to a small region.
-     */
-    if ((uintptr_t)ptr & (SMALL_QUANTUM - 1)) {
-	szone_error(szone, "Non-aligned pointer being freed (2)", ptr);
-	return;
-    }
-    if ((small_region = small_region_for_ptr_no_lock(szone, ptr)) != NULL) {
-	free_small(szone, ptr, small_region);
-	return;
-    }
-
-    /* check that it's a legal large/huge allocation */
-    if ((uintptr_t)ptr & (vm_page_size - 1)) {
-	szone_error(szone, "non-page-aligned, non-allocated pointer being freed", ptr);
-	return;
-    }
-    free_large_or_huge(szone, ptr);
-}
-
-static INLINE void *
-szone_malloc_should_clear(szone_t *szone, size_t size, boolean_t cleared_requested)
-{
-    void	*ptr;
-    msize_t	msize;
-    unsigned	num_pages;
-
-    if (size <= 31*TINY_QUANTUM) {
-	// think tiny
-	msize = TINY_MSIZE_FOR_BYTES(size + TINY_QUANTUM - 1);
-	if (!msize)
-	    msize = 1;
-	ptr = tiny_malloc_should_clear(szone, msize, cleared_requested);
-    } else if (!((szone->debug_flags & SCALABLE_MALLOC_ADD_GUARD_PAGES) && PROTECT_SMALL) && (size < LARGE_THRESHOLD)) {
-	// think small
-	msize = SMALL_MSIZE_FOR_BYTES(size + SMALL_QUANTUM - 1);
-	if (! msize) msize = 1;
-	ptr = small_malloc_should_clear(szone, msize, cleared_requested);
-    } else {
-	// large or huge
-	num_pages = round_page(size) >> vm_page_shift;
-	ptr = large_and_huge_malloc(szone, num_pages);
-    }
-#if DEBUG_MALLOC
-    if (LOG(szone, ptr))
-	malloc_printf("szone_malloc returned %p\n", ptr);
-#endif
-    /*
-     * If requested, scribble on allocated memory.
-     */
-    if ((szone->debug_flags & SCALABLE_MALLOC_DO_SCRIBBLE) && ptr && !cleared_requested && size)
-	memset(ptr, 0xaa, size);
-
-    return ptr;
-}
-
-static void *
-szone_malloc(szone_t *szone, size_t size) {
-    return szone_malloc_should_clear(szone, size, 0);
-}
-
-static void *
-szone_calloc(szone_t *szone, size_t num_items, size_t size)
-{
-    return szone_malloc_should_clear(szone, num_items * size, 1);
-}
-
-static void *
-szone_valloc(szone_t *szone, size_t size)
-{
-    void	*ptr;
-    unsigned	num_pages;
-    
-    num_pages = round_page(size) >> vm_page_shift;
-    ptr = large_and_huge_malloc(szone, num_pages);
-#if DEBUG_MALLOC
-    if (LOG(szone, ptr))
-	malloc_printf("szone_valloc returned %p\n", ptr);
-#endif
-    return ptr;
-}
-
-static size_t
-szone_size(szone_t *szone, const void *ptr)
-{
-    size_t		size = 0;
-    boolean_t		is_free;
-    msize_t		msize, msize_and_free;
-    large_entry_t	*entry;
-    huge_entry_t	*huge;
-    
-    if (!ptr)
-	return 0;
-#if DEBUG_MALLOC
-    if (LOG(szone, ptr)) {
-	malloc_printf("in szone_size for %p (szone=%p)\n", ptr, szone);
-    }
-#endif
-
-    /*
-     * Look for it in a tiny region.
-     */
-    if ((uintptr_t)ptr & (TINY_QUANTUM - 1))
-	return 0;
-    if (tiny_region_for_ptr_no_lock(szone, ptr)) {
-	msize = get_tiny_meta_header(ptr, &is_free);
-	return (is_free) ? 0 : TINY_BYTES_FOR_MSIZE(msize);
-    }
-    
-    /*
-     * Look for it in a small region.
-     */
-    if ((uintptr_t)ptr & (SMALL_QUANTUM - 1))
-	return 0;
-    if (small_region_for_ptr_no_lock(szone, ptr)) {
-	msize_and_free = *SMALL_METADATA_FOR_PTR(ptr);
-	return (msize_and_free & SMALL_IS_FREE) ? 0 : SMALL_BYTES_FOR_MSIZE(msize_and_free);
-    }
-
-    /*
-     * If not page-aligned, it cannot have come from a large or huge allocation.
-     */
-    if ((uintptr_t)ptr & (vm_page_size - 1))
-	return(0);
-
-    /*
-     * Look for it in a large or huge entry.
-     */
-    SZONE_LOCK(szone);
-    entry = large_entry_for_pointer_no_lock(szone, ptr);
-    if (entry) {
-	size = LARGE_ENTRY_SIZE(*entry);
-    } else if ((huge = huge_entry_for_pointer_no_lock(szone, ptr))) {
-	size = huge->size;
-    }
-    SZONE_UNLOCK(szone); 
-#if DEBUG_MALLOC
-    if (LOG(szone, ptr)) {
-	malloc_printf("szone_size for %p returned %d\n", ptr, (unsigned)size);
-    }
-#endif
-    return size;
-}
-
-static void *
-szone_realloc(szone_t *szone, void *ptr, size_t new_size)
-{
-    size_t		old_size;
-    void		*new_ptr;
-    
-#if DEBUG_MALLOC
-    if (LOG(szone, ptr)) {
-	malloc_printf("in szone_realloc for %p, %d\n", ptr, (unsigned)new_size);
-    }
-#endif
-    if (!ptr) {
-	ptr = szone_malloc(szone, new_size);
-	return ptr;
-    }
-    old_size = szone_size(szone, ptr);
-    if (!old_size) {
-	szone_error(szone, "pointer being reallocated was not allocated", ptr);
-	return NULL;
-    }
-    /* we never shrink an allocation */
-    if (old_size >= new_size)
-	return ptr;
-
-    /*
-     * If the old and new sizes both suit the tiny allocator, try to reallocate in-place.
-     */
-    if ((new_size + TINY_QUANTUM - 1) <= 31 * TINY_QUANTUM) {
-	if (try_realloc_tiny_in_place(szone, ptr, old_size, new_size)) {
-	    return ptr;
-	}
-
-	/*
-	 * If the old and new sizes both suit the small allocator, and we're not protecting the
-	 * small allocations, try to reallocate in-place.
-	 */
-    } else if (!((szone->debug_flags & SCALABLE_MALLOC_ADD_GUARD_PAGES) && PROTECT_SMALL) &&
-      ((new_size + SMALL_QUANTUM - 1) < LARGE_THRESHOLD) &&
-      (old_size > 31 * TINY_QUANTUM)) {
-	if (try_realloc_small_in_place(szone, ptr, old_size, new_size)) {
-	    return ptr;
-	}
-
-	/*
-	 * If the allocation's a large or huge allocation, try to reallocate in-place there.
-	 */
-    } else if (!((szone->debug_flags & SCALABLE_MALLOC_ADD_GUARD_PAGES) && PROTECT_SMALL) && (old_size > LARGE_THRESHOLD)) {
-	if (try_realloc_large_or_huge_in_place(szone, ptr, old_size, new_size)) {
-	    return ptr;
-	}
-    }
-
-    /*
-     * Can't reallocate in place for whatever reason; allocate a new buffer and copy.
-     */
-    new_ptr = szone_malloc(szone, new_size);
-    if (new_ptr == NULL)
-	return NULL;
-
-    /*
-     * If the allocation's large enough, try to copy using VM.  If that fails, or
-     * if it's too small, just copy by hand.
-     */
-    if ((old_size < VM_COPY_THRESHOLD) ||
-      vm_copy(mach_task_self(), (vm_address_t)ptr, old_size, (vm_address_t)new_ptr))
-	memcpy(new_ptr, ptr, old_size);
-    szone_free(szone, ptr);
-    
-#if DEBUG_MALLOC
-    if (LOG(szone, ptr)) {
-	malloc_printf("szone_realloc returned %p for %d\n", new_ptr, (unsigned)new_size);
-    }
-#endif
-    return new_ptr;
-}
-
-// given a size, returns pointers capable of holding that size
-// returns the number of pointers allocated
-// may return 0 - this function will do best attempts, but just that
-static unsigned
-szone_batch_malloc(szone_t *szone, size_t size, void **results, unsigned count)
-{
-    msize_t		msize = TINY_MSIZE_FOR_BYTES(size + TINY_QUANTUM - 1);
-    size_t		chunk_size = TINY_BYTES_FOR_MSIZE(msize);
-    free_list_t		**free_list = szone->tiny_free_list + msize - 1;
-    free_list_t		*ptr = *free_list;
-    unsigned		found = 0;
-
-    if (size > 31*TINY_QUANTUM)
-	return 0; // only bother implementing this for tiny
-    if (!msize)
-	msize = 1;
-    CHECK(szone, __PRETTY_FUNCTION__);
-    SZONE_LOCK(szone); // might as well lock right here to avoid concurrency issues
-    while (found < count) {
-	if (!ptr)
-	    break;
-	*results++ = ptr;
-	found++;
-	set_tiny_meta_header_in_use(ptr, msize);
-	ptr = ptr->next;
-    }
-    if (ptr) {
-	ptr->previous = NULL;
-	free_list_set_checksum(szone, ptr);
-    }
-    *free_list = ptr;
-
-    // Note that we could allocate from the free lists for larger msize
-    // But that may un-necessarily fragment - so we might as well let the client do that
-    // We could also allocate from szone->tiny_bytes_free_at_end
-    // But that means we'll "eat-up" the untouched area faster, increasing the working set
-    // So we just return what we have and just that
-    szone->num_tiny_objects += found;
-    szone->num_bytes_in_tiny_objects += chunk_size * found;
-    SZONE_UNLOCK(szone);
-    return found;
-}
-
-static void
-szone_batch_free(szone_t *szone, void **to_be_freed, unsigned count)
-{
-    unsigned		cc = 0;
-    void		*ptr;
-    tiny_region_t	*tiny_region;
-    boolean_t		is_free;
-    msize_t		msize;
-
-    // frees all the pointers in to_be_freed
-    // note that to_be_freed may be overwritten during the process
-    if (!count)
-	return;
-    CHECK(szone, __PRETTY_FUNCTION__);
-    SZONE_LOCK(szone);
-    while (cc < count) {
-	ptr = to_be_freed[cc];
-	/* XXX this really slows us down */
-	tiny_region = tiny_region_for_ptr_no_lock(szone, ptr);
-	if (tiny_region) {
-	    // this is a tiny pointer
-	    msize = get_tiny_meta_header(ptr, &is_free);
-	    if (is_free)
-		break; // a double free; let the standard free deal with it
-	    tiny_free_no_lock(szone, tiny_region, ptr, msize);
-	    to_be_freed[cc] = NULL;
-	}
-	cc++;
-    }
-    SZONE_UNLOCK(szone);
-    CHECK(szone, __PRETTY_FUNCTION__);
-    while (count--) {
-	ptr = to_be_freed[count];
-	if (ptr)
-	    szone_free(szone, ptr);
-    }
-}
-
-static void
-szone_destroy(szone_t *szone)
-{
-    unsigned		index;
-    small_region_t	pended_region = 0;
-    large_entry_t	*large;
-    vm_range_t		range_to_deallocate;
-    huge_entry_t	*huge;
-    tiny_region_t	tiny_region;
-    small_region_t	small_region;
-
-    /* destroy large entries */
-    index = szone->num_large_entries;
-    while (index--) {
-	large = szone->large_entries + index;
-	if (!LARGE_ENTRY_IS_EMPTY(*large)) {
-	    // we deallocate_pages, including guard pages
-	    deallocate_pages(szone, (void *)LARGE_ENTRY_ADDRESS(*large), LARGE_ENTRY_SIZE(*large), szone->debug_flags);
-	}
-    }
-    if (szone->num_large_entries * sizeof(large_entry_t) >= LARGE_THRESHOLD) {
-	// we do not free in the small chunk case
-	large_entries_free_no_lock(szone, szone->large_entries, szone->num_large_entries, &range_to_deallocate);
-	if (range_to_deallocate.size)
-	    deallocate_pages(szone, (void *)range_to_deallocate.address, (size_t)range_to_deallocate.size, 0);
-    }
-
-    /* destroy huge entries */
-    index = szone->num_huge_entries;
-    while (index--) {
-	huge = szone->huge_entries + index;
-	deallocate_pages(szone, (void *)huge->address, huge->size, szone->debug_flags);
-    }
-    
-    /* destroy tiny regions */
-    index = szone->num_tiny_regions;
-    while (index--) {
-        tiny_region = szone->tiny_regions[index];
-	deallocate_pages(szone, TINY_REGION_ADDRESS(tiny_region), TINY_REGION_SIZE, 0);
-    }
-    /* destroy small regions; region 0 must go last as it contains the szone */
-    index = szone->num_small_regions;
-    while (index--) {
-        small_region = szone->small_regions[index];
-	/*
-	 * If we've allocated more than the basic set of small regions, avoid destroying the
-	 * region that contains the array.
-	 */
-	if ((index > 0) &&
-	  (SMALL_REGION_FOR_PTR(szone->small_regions) == SMALL_REGION_ADDRESS(small_region))) {
-		pended_region = small_region;
-	} else {
-		deallocate_pages(szone, (void *)SMALL_REGION_ADDRESS(small_region), SMALL_REGION_SIZE, 0);
-	}
-    }
-    if (pended_region)
-        deallocate_pages(NULL, (void *)SMALL_REGION_ADDRESS(pended_region), SMALL_REGION_SIZE, 0);
-}
-
-static size_t
-szone_good_size(szone_t *szone, size_t size)
-{
-    msize_t	msize;
-    unsigned	num_pages;
-    
-    if (size <= 31 * TINY_QUANTUM) {
-	// think tiny
-	msize = TINY_MSIZE_FOR_BYTES(size + TINY_QUANTUM - 1);
-	if (! msize) msize = 1;
-	return TINY_BYTES_FOR_MSIZE(msize);
-    }
-    if (!((szone->debug_flags & SCALABLE_MALLOC_ADD_GUARD_PAGES) && PROTECT_SMALL) && (size < LARGE_THRESHOLD)) {
-	// think small
-	msize = SMALL_MSIZE_FOR_BYTES(size + SMALL_QUANTUM - 1);
-	if (! msize) msize = 1;
-	return SMALL_BYTES_FOR_MSIZE(msize);
-    } else {
-	num_pages = round_page(size) >> vm_page_shift;
-	if (!num_pages)
-	    num_pages = 1; // minimal allocation size for this
-	return num_pages << vm_page_shift;
-    }
-}
-
-unsigned szone_check_counter = 0;
-unsigned szone_check_start = 0;
-unsigned szone_check_modulo = 1;
-
-static boolean_t
-szone_check_all(szone_t *szone, const char *function)
-{
-    int			index;
-    tiny_region_t	*tiny;
-    small_region_t	*small;
-    
-    SZONE_LOCK(szone);
-    CHECK_LOCKED(szone, __PRETTY_FUNCTION__);
-
-    /* check tiny regions - chould check region count */
-    for (index = szone->num_tiny_regions - 1, tiny = szone->tiny_regions;
-	 index >= 0;
-	 index--, tiny++) {
-	if (!tiny_check_region(szone, tiny)) {
-	    SZONE_UNLOCK(szone);
-	    szone->debug_flags &= ~ CHECK_REGIONS;
-	    malloc_printf("*** tiny region %d incorrect szone_check_all(%s) counter=%d\n",
-		szone->num_tiny_regions - index, function, szone_check_counter);
-	    szone_error(szone, "check: tiny region incorrect", NULL);
-	    return 0;
-	}
-    }
-
-    for (index = NUM_TINY_SLOTS - 1; index >= 0; index--) {
-	if (!tiny_free_list_check(szone, index)) {
-	    SZONE_UNLOCK(szone);
-	    szone->debug_flags &= ~ CHECK_REGIONS;
-	    malloc_printf("*** tiny free list incorrect (slot=%d) szone_check_all(%s) counter=%d\n",
-	      index, function, szone_check_counter);
-	    szone_error(szone, "check: tiny free list incorrect", NULL);
-	    return 0;
-	}
-    }
-
-    /* check small regions - could check region count */
-    for (index = szone->num_small_regions - 1, small = szone->small_regions;
-	 index >= 0;
-	 index--, small++) {
-	if (!szone_check_small_region(szone, small)) {
-	    SZONE_UNLOCK(szone);
-	    szone->debug_flags &= ~ CHECK_REGIONS;
-	    malloc_printf("*** small region %d incorrect szone_check_all(%s) counter=%d\n",
-	      szone->num_small_regions, index, function, szone_check_counter);
-	    szone_error(szone, "check: small region incorrect", NULL);
-	    return 0;
-	}
-    }
-    for (index = NUM_SMALL_SLOTS - 1; index >= 0; index--) {
-	if (!small_free_list_check(szone, index)) {
-	    SZONE_UNLOCK(szone);
-	    szone->debug_flags &= ~ CHECK_REGIONS;
-	    malloc_printf("*** small free list incorrect (grain=%d) szone_check_all(%s) counter=%d\n", index, function, szone_check_counter);
-	    szone_error(szone, "check: small free list incorrect", NULL);
-	    return 0;
-	}
-    }
-    SZONE_UNLOCK(szone);
-    // szone_print(szone, 1);
-    return 1;
-}
-
-static boolean_t
-szone_check(szone_t *szone)
-{
-
-    if ((++szone_check_counter % 10000) == 0)
-	malloc_printf("at szone_check counter=%d\n", szone_check_counter);
-    if (szone_check_counter < szone_check_start)
-	return 1;
-    if (szone_check_counter % szone_check_modulo)
-	return 1;
-    return szone_check_all(szone, "");
-}
-
-static kern_return_t
-szone_ptr_in_use_enumerator(task_t task, void *context, unsigned type_mask, vm_address_t zone_address, memory_reader_t reader, vm_range_recorder_t recorder)
-{
-    szone_t		*szone;
-    kern_return_t	err;
-    
-    if (!reader) reader = _szone_default_reader;
-    err = reader(task, zone_address, sizeof(szone_t), (void **)&szone);
-    if (err) return err;
-    err = tiny_in_use_enumerator(task, context, type_mask,
-      (vm_address_t)szone->tiny_regions, szone->num_tiny_regions, szone->tiny_bytes_free_at_end , reader, recorder);
-    if (err) return err;
-    err = small_in_use_enumerator(task, context, type_mask,
-      (vm_address_t)szone->small_regions, szone->num_small_regions, szone->small_bytes_free_at_end , reader, recorder);
-    if (err) return err;
-    err = large_in_use_enumerator(task, context, type_mask,
-      (vm_address_t)szone->large_entries, szone->num_large_entries, reader,
-      recorder);
-    if (err) return err;
-    err = huge_in_use_enumerator(task, context, type_mask,
-      (vm_address_t)szone->huge_entries, szone->num_huge_entries, reader,
-      recorder);
-    return err;
-}
-
-// Following method is deprecated:  use scalable_zone_statistics instead
-void
-scalable_zone_info(malloc_zone_t *zone, unsigned *info_to_fill, unsigned count)
-{
-    szone_t	*szone = (void *)zone;
-    unsigned	info[13];
-    
-    // We do not lock to facilitate debug
-    info[4] = szone->num_tiny_objects;
-    info[5] = szone->num_bytes_in_tiny_objects;
-    info[6] = szone->num_small_objects;
-    info[7] = szone->num_bytes_in_small_objects;
-    info[8] = szone->num_large_objects_in_use;
-    info[9] = szone->num_bytes_in_large_objects;
-    info[10] = szone->num_huge_entries;
-    info[11] = szone->num_bytes_in_huge_objects;
-    info[12] = szone->debug_flags;
-    info[0] = info[4] + info[6] + info[8] + info[10];
-    info[1] = info[5] + info[7] + info[9] + info[11];
-    info[3] = szone->num_tiny_regions * TINY_REGION_SIZE + szone->num_small_regions * SMALL_REGION_SIZE + info[9] + info[11];
-    info[2] = info[3] - szone->tiny_bytes_free_at_end - szone->small_bytes_free_at_end;
-    memcpy(info_to_fill, info, sizeof(unsigned)*count);
-}
-
-static void
-szone_print(szone_t *szone, boolean_t verbose)
-{
-    unsigned		info[13];
-    unsigned		index = 0;
-    tiny_region_t	*region;
-    
-    SZONE_LOCK(szone);
-    scalable_zone_info((void *)szone, info, 13);
-    malloc_printf("Scalable zone %p: inUse=%d(%y) touched=%y allocated=%y flags=%d\n",
-      szone, info[0], info[1], info[2], info[3], info[12]);
-    malloc_printf("\ttiny=%d(%y) small=%d(%y) large=%d(%y) huge=%d(%y)\n",
-      info[4], info[5], info[6], info[7], info[8], info[9], info[10], info[11]);
-    // tiny
-    malloc_printf("%d tiny regions: \n", szone->num_tiny_regions);
-    while (index < szone->num_tiny_regions) {
-	region = szone->tiny_regions + index;
-	print_tiny_region(verbose, *region, (index == szone->num_tiny_regions - 1) ? szone->tiny_bytes_free_at_end : 0);
-	index++;
-    }
-    if (verbose) print_tiny_free_list(szone);
-    // small
-    malloc_printf("%d small regions: \n", szone->num_small_regions);
-    index = 0; 
-    while (index < szone->num_small_regions) {
-	region = szone->small_regions + index;
-	print_small_region(szone, verbose, region, (index == szone->num_small_regions - 1) ? szone->small_bytes_free_at_end : 0);
-	index++;
-    }
-    if (verbose)
-	print_small_free_list(szone);
-    SZONE_UNLOCK(szone);
-}
-
-static void
-szone_log(malloc_zone_t *zone, void *log_address)
-{
-    szone_t	*szone = (szone_t *)zone;
-
-    szone->log_address = log_address;
-}
-
-static void
-szone_force_lock(szone_t *szone)
-{
-    SZONE_LOCK(szone);
-}
-
-static void
-szone_force_unlock(szone_t *szone)
-{
-    SZONE_UNLOCK(szone);
-}
-
-boolean_t
-scalable_zone_statistics(malloc_zone_t *zone, malloc_statistics_t *stats, unsigned subzone)
-{
-    szone_t *szone = (szone_t *)zone;
-    
-    switch (subzone) {
-	case 0:	
-	    stats->blocks_in_use = szone->num_tiny_objects;
-	    stats->size_in_use = szone->num_bytes_in_tiny_objects;
-	    stats->size_allocated = szone->num_tiny_regions * TINY_REGION_SIZE;
-	    stats->max_size_in_use = stats->size_allocated - szone->tiny_bytes_free_at_end;
-	    return 1;
-	case 1:	
-	    stats->blocks_in_use = szone->num_small_objects;
-	    stats->size_in_use = szone->num_bytes_in_small_objects;
-	    stats->size_allocated = szone->num_small_regions * SMALL_REGION_SIZE;
-	    stats->max_size_in_use = stats->size_allocated - szone->small_bytes_free_at_end;
-	    return 1;
-	case 2:
-	    stats->blocks_in_use = szone->num_large_objects_in_use;
-	    stats->size_in_use = szone->num_bytes_in_large_objects;
-	    stats->max_size_in_use = stats->size_allocated = stats->size_in_use;
-	    return 1;
-	case 3:
-	    stats->blocks_in_use = szone->num_huge_entries;
-	    stats->size_in_use = szone->num_bytes_in_huge_objects;
-	    stats->max_size_in_use = stats->size_allocated = stats->size_in_use;
-	    return 1;
-    }
-    return 0;
-}
-
-static void
-szone_statistics(szone_t *szone, malloc_statistics_t *stats)
-{
-    size_t	big_and_huge;
-    
-    stats->blocks_in_use =
-      szone->num_tiny_objects +
-      szone->num_small_objects +
-      szone->num_large_objects_in_use +
-      szone->num_huge_entries;
-    big_and_huge = szone->num_bytes_in_large_objects + szone->num_bytes_in_huge_objects;
-    stats->size_in_use = szone->num_bytes_in_tiny_objects + szone->num_bytes_in_small_objects + big_and_huge;
-    stats->max_size_in_use = stats->size_allocated =
-      szone->num_tiny_regions * TINY_REGION_SIZE +
-      szone->num_small_regions * SMALL_REGION_SIZE +
-      big_and_huge ; 
-
-    // Now we account for the untouched areas
-    stats->max_size_in_use -= szone->tiny_bytes_free_at_end;
-    stats->max_size_in_use -= szone->small_bytes_free_at_end;
-}
-
-static const struct malloc_introspection_t szone_introspect = {
-    (void *)szone_ptr_in_use_enumerator,
-    (void *)szone_good_size,
-    (void *)szone_check,
-    (void *)szone_print,
-    szone_log,
-    (void *)szone_force_lock,
-    (void *)szone_force_unlock,
-    (void *)szone_statistics
-}; // marked as const to spare the DATA section
-
-malloc_zone_t *
-create_scalable_zone(size_t initial_size, unsigned debug_flags)
-{
-    szone_t		*szone;
-    size_t		msize;
-    size_t		msize_used;
-    msize_t		free_msize;
-
-    /*
-     * Sanity-check our build-time assumptions about the size of a page.
-     * Since we have sized various things assuming the default page size,
-     * attempting to determine it dynamically is not useful.
-     */
-    if ((vm_page_size != _vm_page_size) || (vm_page_shift != _vm_page_shift)) {
-	malloc_printf("*** FATAL ERROR - machine page size does not match our assumptions.\n");
-	exit(-1);
-    }
-
-    /* get memory for the zone */
-    szone = allocate_pages(NULL, SMALL_REGION_SIZE, SMALL_BLOCKS_ALIGN, 0, VM_MAKE_TAG(VM_MEMORY_MALLOC));
-    if (!szone)
-	return NULL;
-    /* set up the szone structure */
-    szone->tiny_regions = szone->initial_tiny_regions;
-    szone->small_regions = szone->initial_small_regions;
-    msize_used = msize; szone->num_small_objects++;
-    szone->basic_zone.version = 3;
-    szone->basic_zone.size = (void *)szone_size;
-    szone->basic_zone.malloc = (void *)szone_malloc;
-    szone->basic_zone.calloc = (void *)szone_calloc;
-    szone->basic_zone.valloc = (void *)szone_valloc;
-    szone->basic_zone.free = (void *)szone_free;
-    szone->basic_zone.realloc = (void *)szone_realloc;
-    szone->basic_zone.destroy = (void *)szone_destroy;
-    szone->basic_zone.batch_malloc = (void *)szone_batch_malloc;
-    szone->basic_zone.batch_free = (void *)szone_batch_free;
-    szone->basic_zone.introspect = (struct malloc_introspection_t *)&szone_introspect;
-    szone->debug_flags = debug_flags;
-
-    /* as the szone is allocated out of the first tiny, region, reflect that allocation */
-    szone->small_regions[0] = szone;
-    szone->num_small_regions = 1;
-    msize = SMALL_MSIZE_FOR_BYTES(sizeof(szone_t) + SMALL_QUANTUM - 1);
-    free_msize = NUM_SMALL_BLOCKS - msize;
-    *SMALL_METADATA_FOR_PTR(szone) = msize;
-    *(SMALL_METADATA_FOR_PTR(szone) + msize) = free_msize;
-    szone->small_bytes_free_at_end = SMALL_BYTES_FOR_MSIZE(free_msize);
-
-    LOCK_INIT(szone->lock);
-#if 0
-#warning CHECK_REGIONS enabled
-    debug_flags |= CHECK_REGIONS;
-#endif
-#if 0
-#warning LOG enabled
-    szone->log_address = ~0;
-#endif
-    CHECK(szone, __PRETTY_FUNCTION__);
-    return (malloc_zone_t *)szone;
-}
-
-/********* Support code for emacs unexec ************/
-
-/* History of freezedry version numbers:
- *
- * 1) Old malloc (before the scalable malloc implementation in this file
- *    existed).
- * 2) Original freezedrying code for scalable malloc.  This code was apparently
- *    based on the old freezedrying code and was fundamentally flawed in its
- *    assumption that tracking allocated memory regions was adequate to fake
- *    operations on freezedried memory.  This doesn't work, since scalable
- *    malloc does not store flags in front of large page-aligned allocations.
- * 3) Original szone-based freezedrying code.
- * 4) Fresher malloc with tiny zone
- * 5) 32/64bit compatible malloc
- *
- * No version backward compatibility is provided, but the version number does
- * make it possible for malloc_jumpstart() to return an error if the application
- * was freezedried with an older version of malloc.
- */
-#define MALLOC_FREEZEDRY_VERSION 5
-
-typedef struct {
-    unsigned version;
-    unsigned nszones;
-    szone_t *szones;
-} malloc_frozen;
-
-static void *
-frozen_malloc(szone_t *zone, size_t new_size)
-{
-    return malloc(new_size);
-}
-
-static void *
-frozen_calloc(szone_t *zone, size_t num_items, size_t size)
-{
-    return calloc(num_items, size);
-}
-
-static void *
-frozen_valloc(szone_t *zone, size_t new_size)
-{
-    return valloc(new_size);
-}
-
-static void *
-frozen_realloc(szone_t *zone, void *ptr, size_t new_size)
-{
-    size_t	old_size = szone_size(zone, ptr);
-    void	*new_ptr;
-    
-    if (new_size <= old_size) {
-	return ptr;
-    }
-    new_ptr = malloc(new_size);
-    if (old_size > 0) {
-	memcpy(new_ptr, ptr, old_size);
-    }
-    return new_ptr;
-}
-
-static void
-frozen_free(szone_t *zone, void *ptr)
-{
-}
-
-static void
-frozen_destroy(szone_t *zone)
-{
-}
-
-/********* Pseudo-private API for emacs unexec ************/
-
-/*
- * malloc_freezedry() records all of the szones in use, so that they can be
- * partially reconstituted by malloc_jumpstart().  Due to the differences
- * between reconstituted memory regions and those created by the szone code,
- * care is taken not to reallocate from the freezedried memory, except in the
- * case of a non-growing realloc().
- *
- * Due to the flexibility provided by the zone registration mechanism, it is
- * impossible to implement generic freezedrying for any zone type.  This code
- * only handles applications that use the szone allocator, so malloc_freezedry()
- * returns 0 (error) if any non-szone zones are encountered.
- */
-
-uintptr_t
-malloc_freezedry(void)
-{
-    extern unsigned malloc_num_zones;
-    extern malloc_zone_t **malloc_zones;
-    malloc_frozen *data;
-    unsigned i;
-
-    /* Allocate space in which to store the freezedry state. */
-    data = (malloc_frozen *) malloc(sizeof(malloc_frozen));
-
-    /* Set freezedry version number so that malloc_jumpstart() can check for compatibility. */
-    data->version = MALLOC_FREEZEDRY_VERSION;
-
-    /* Allocate the array of szone pointers. */
-    data->nszones = malloc_num_zones;
-    data->szones = (szone_t *) calloc(malloc_num_zones, sizeof(szone_t));
-
-    /*
-     * Fill in the array of szone structures.  They are copied rather than
-     * referenced, since the originals are likely to be clobbered during malloc
-     * initialization.
-     */
-    for (i = 0; i < malloc_num_zones; i++) {
-	if (strcmp(malloc_zones[i]->zone_name, "DefaultMallocZone")) {
-	    /* Unknown zone type. */
-	    free(data->szones);
-	    free(data);
-	    return 0;
-	}
-	memcpy(&data->szones[i], malloc_zones[i], sizeof(szone_t));
-    }
-
-    return((uintptr_t)data);
-}
-
-int
-malloc_jumpstart(uintptr_t cookie)
-{
-    malloc_frozen *data = (malloc_frozen *)cookie;
-    unsigned i;
-
-    if (data->version != MALLOC_FREEZEDRY_VERSION) {
-	/* Unsupported freezedry version. */
-	return 1;
-    }
-
-    for (i = 0; i < data->nszones; i++) {
-	/* Set function pointers.  Even the functions that stay the same must be
-	 * set, since there are no guarantees that they will be mapped to the
-	 * same addresses. */
-	data->szones[i].basic_zone.size = (void *) szone_size;
-	data->szones[i].basic_zone.malloc = (void *) frozen_malloc;
-	data->szones[i].basic_zone.calloc = (void *) frozen_calloc;
-	data->szones[i].basic_zone.valloc = (void *) frozen_valloc;
-	data->szones[i].basic_zone.free = (void *) frozen_free;
-	data->szones[i].basic_zone.realloc = (void *) frozen_realloc;
-	data->szones[i].basic_zone.destroy = (void *) frozen_destroy;
-	data->szones[i].basic_zone.introspect = (struct malloc_introspection_t *)&szone_introspect;
-
-	/* Register the freezedried zone. */
-	malloc_zone_register(&data->szones[i].basic_zone);
-    }
-
-    return 0;
-}
-