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axmol/scripting/lua/luajit/LuaJIT-2.0.1/src/lj_alloc.c

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/*
** Bundled memory allocator.
**
** Beware: this is a HEAVILY CUSTOMIZED version of dlmalloc.
** The original bears the following remark:
**
** This is a version (aka dlmalloc) of malloc/free/realloc written by
** Doug Lea and released to the public domain, as explained at
** http://creativecommons.org/licenses/publicdomain.
**
** * Version pre-2.8.4 Wed Mar 29 19:46:29 2006 (dl at gee)
**
** No additional copyright is claimed over the customizations.
** Please do NOT bother the original author about this version here!
**
** If you want to use dlmalloc in another project, you should get
** the original from: ftp://gee.cs.oswego.edu/pub/misc/
** For thread-safe derivatives, take a look at:
** - ptmalloc: http://www.malloc.de/
** - nedmalloc: http://www.nedprod.com/programs/portable/nedmalloc/
*/
#define lj_alloc_c
#define LUA_CORE
/* To get the mremap prototype. Must be defined before any system includes. */
#if defined(__linux__) && !defined(_GNU_SOURCE)
#define _GNU_SOURCE
#endif
#include "lj_def.h"
#include "lj_arch.h"
#include "lj_alloc.h"
#ifndef LUAJIT_USE_SYSMALLOC
#define MAX_SIZE_T (~(size_t)0)
#define MALLOC_ALIGNMENT ((size_t)8U)
#define DEFAULT_GRANULARITY ((size_t)128U * (size_t)1024U)
#define DEFAULT_TRIM_THRESHOLD ((size_t)2U * (size_t)1024U * (size_t)1024U)
#define DEFAULT_MMAP_THRESHOLD ((size_t)128U * (size_t)1024U)
#define MAX_RELEASE_CHECK_RATE 255
/* ------------------- size_t and alignment properties -------------------- */
/* The byte and bit size of a size_t */
#define SIZE_T_SIZE (sizeof(size_t))
#define SIZE_T_BITSIZE (sizeof(size_t) << 3)
/* Some constants coerced to size_t */
/* Annoying but necessary to avoid errors on some platforms */
#define SIZE_T_ZERO ((size_t)0)
#define SIZE_T_ONE ((size_t)1)
#define SIZE_T_TWO ((size_t)2)
#define TWO_SIZE_T_SIZES (SIZE_T_SIZE<<1)
#define FOUR_SIZE_T_SIZES (SIZE_T_SIZE<<2)
#define SIX_SIZE_T_SIZES (FOUR_SIZE_T_SIZES+TWO_SIZE_T_SIZES)
/* The bit mask value corresponding to MALLOC_ALIGNMENT */
#define CHUNK_ALIGN_MASK (MALLOC_ALIGNMENT - SIZE_T_ONE)
/* the number of bytes to offset an address to align it */
#define align_offset(A)\
((((size_t)(A) & CHUNK_ALIGN_MASK) == 0)? 0 :\
((MALLOC_ALIGNMENT - ((size_t)(A) & CHUNK_ALIGN_MASK)) & CHUNK_ALIGN_MASK))
/* -------------------------- MMAP support ------------------------------- */
#define MFAIL ((void *)(MAX_SIZE_T))
#define CMFAIL ((char *)(MFAIL)) /* defined for convenience */
#define IS_DIRECT_BIT (SIZE_T_ONE)
#if LJ_TARGET_WINDOWS
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#if LJ_64
/* Undocumented, but hey, that's what we all love so much about Windows. */
typedef long (*PNTAVM)(HANDLE handle, void **addr, ULONG zbits,
size_t *size, ULONG alloctype, ULONG prot);
static PNTAVM ntavm;
/* Number of top bits of the lower 32 bits of an address that must be zero.
** Apparently 0 gives us full 64 bit addresses and 1 gives us the lower 2GB.
*/
#define NTAVM_ZEROBITS 1
static void INIT_MMAP(void)
{
ntavm = (PNTAVM)GetProcAddress(GetModuleHandleA("ntdll.dll"),
"NtAllocateVirtualMemory");
}
/* Win64 32 bit MMAP via NtAllocateVirtualMemory. */
static LJ_AINLINE void *CALL_MMAP(size_t size)
{
DWORD olderr = GetLastError();
void *ptr = NULL;
long st = ntavm(INVALID_HANDLE_VALUE, &ptr, NTAVM_ZEROBITS, &size,
MEM_RESERVE|MEM_COMMIT, PAGE_READWRITE);
SetLastError(olderr);
return st == 0 ? ptr : MFAIL;
}
/* For direct MMAP, use MEM_TOP_DOWN to minimize interference */
static LJ_AINLINE void *DIRECT_MMAP(size_t size)
{
DWORD olderr = GetLastError();
void *ptr = NULL;
long st = ntavm(INVALID_HANDLE_VALUE, &ptr, NTAVM_ZEROBITS, &size,
MEM_RESERVE|MEM_COMMIT|MEM_TOP_DOWN, PAGE_READWRITE);
SetLastError(olderr);
return st == 0 ? ptr : MFAIL;
}
#else
#define INIT_MMAP() ((void)0)
/* Win32 MMAP via VirtualAlloc */
static LJ_AINLINE void *CALL_MMAP(size_t size)
{
DWORD olderr = GetLastError();
void *ptr = VirtualAlloc(0, size, MEM_RESERVE|MEM_COMMIT, PAGE_READWRITE);
SetLastError(olderr);
return ptr ? ptr : MFAIL;
}
/* For direct MMAP, use MEM_TOP_DOWN to minimize interference */
static LJ_AINLINE void *DIRECT_MMAP(size_t size)
{
DWORD olderr = GetLastError();
void *ptr = VirtualAlloc(0, size, MEM_RESERVE|MEM_COMMIT|MEM_TOP_DOWN,
PAGE_READWRITE);
SetLastError(olderr);
return ptr ? ptr : MFAIL;
}
#endif
/* This function supports releasing coalesed segments */
static LJ_AINLINE int CALL_MUNMAP(void *ptr, size_t size)
{
DWORD olderr = GetLastError();
MEMORY_BASIC_INFORMATION minfo;
char *cptr = (char *)ptr;
while (size) {
if (VirtualQuery(cptr, &minfo, sizeof(minfo)) == 0)
return -1;
if (minfo.BaseAddress != cptr || minfo.AllocationBase != cptr ||
minfo.State != MEM_COMMIT || minfo.RegionSize > size)
return -1;
if (VirtualFree(cptr, 0, MEM_RELEASE) == 0)
return -1;
cptr += minfo.RegionSize;
size -= minfo.RegionSize;
}
SetLastError(olderr);
return 0;
}
#else
#include <errno.h>
#include <sys/mman.h>
#define MMAP_PROT (PROT_READ|PROT_WRITE)
#if !defined(MAP_ANONYMOUS) && defined(MAP_ANON)
#define MAP_ANONYMOUS MAP_ANON
#endif
#define MMAP_FLAGS (MAP_PRIVATE|MAP_ANONYMOUS)
#if LJ_64
/* 64 bit mode needs special support for allocating memory in the lower 2GB. */
#if LJ_TARGET_LINUX
/* Actually this only gives us max. 1GB in current Linux kernels. */
static LJ_AINLINE void *CALL_MMAP(size_t size)
{
int olderr = errno;
void *ptr = mmap(NULL, size, MMAP_PROT, MAP_32BIT|MMAP_FLAGS, -1, 0);
errno = olderr;
return ptr;
}
#elif LJ_TARGET_OSX || defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__OpenBSD__)
/* OSX and FreeBSD mmap() use a naive first-fit linear search.
** That's perfect for us. Except that -pagezero_size must be set for OSX,
** otherwise the lower 4GB are blocked. And the 32GB RLIMIT_DATA needs
** to be reduced to 250MB on FreeBSD.
*/
#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__OpenBSD__)
#include <sys/resource.h>
#define MMAP_REGION_START ((uintptr_t)0x10000000)
#else
#define MMAP_REGION_START ((uintptr_t)0x10000)
#endif
#define MMAP_REGION_END ((uintptr_t)0x80000000)
static LJ_AINLINE void *CALL_MMAP(size_t size)
{
int olderr = errno;
/* Hint for next allocation. Doesn't need to be thread-safe. */
static uintptr_t alloc_hint = MMAP_REGION_START;
int retry = 0;
#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
static int rlimit_modified = 0;
if (LJ_UNLIKELY(rlimit_modified == 0)) {
struct rlimit rlim;
rlim.rlim_cur = rlim.rlim_max = MMAP_REGION_START;
setrlimit(RLIMIT_DATA, &rlim); /* Ignore result. May fail below. */
rlimit_modified = 1;
}
#endif
for (;;) {
void *p = mmap((void *)alloc_hint, size, MMAP_PROT, MMAP_FLAGS, -1, 0);
if ((uintptr_t)p >= MMAP_REGION_START &&
(uintptr_t)p + size < MMAP_REGION_END) {
alloc_hint = (uintptr_t)p + size;
errno = olderr;
return p;
}
if (p != CMFAIL) munmap(p, size);
if (retry) break;
retry = 1;
alloc_hint = MMAP_REGION_START;
}
errno = olderr;
return CMFAIL;
}
#else
#error "NYI: need an equivalent of MAP_32BIT for this 64 bit OS"
#endif
#else
/* 32 bit mode is easy. */
static LJ_AINLINE void *CALL_MMAP(size_t size)
{
int olderr = errno;
void *ptr = mmap(NULL, size, MMAP_PROT, MMAP_FLAGS, -1, 0);
errno = olderr;
return ptr;
}
#endif
#define INIT_MMAP() ((void)0)
#define DIRECT_MMAP(s) CALL_MMAP(s)
static LJ_AINLINE int CALL_MUNMAP(void *ptr, size_t size)
{
int olderr = errno;
int ret = munmap(ptr, size);
errno = olderr;
return ret;
}
#if LJ_TARGET_LINUX
/* Need to define _GNU_SOURCE to get the mremap prototype. */
static LJ_AINLINE void *CALL_MREMAP_(void *ptr, size_t osz, size_t nsz,
int flags)
{
int olderr = errno;
ptr = mremap(ptr, osz, nsz, flags);
errno = olderr;
return ptr;
}
#define CALL_MREMAP(addr, osz, nsz, mv) CALL_MREMAP_((addr), (osz), (nsz), (mv))
#define CALL_MREMAP_NOMOVE 0
#define CALL_MREMAP_MAYMOVE 1
#if LJ_64
#define CALL_MREMAP_MV CALL_MREMAP_NOMOVE
#else
#define CALL_MREMAP_MV CALL_MREMAP_MAYMOVE
#endif
#endif
#endif
#ifndef CALL_MREMAP
#define CALL_MREMAP(addr, osz, nsz, mv) ((void)osz, MFAIL)
#endif
/* ----------------------- Chunk representations ------------------------ */
struct malloc_chunk {
size_t prev_foot; /* Size of previous chunk (if free). */
size_t head; /* Size and inuse bits. */
struct malloc_chunk *fd; /* double links -- used only if free. */
struct malloc_chunk *bk;
};
typedef struct malloc_chunk mchunk;
typedef struct malloc_chunk *mchunkptr;
typedef struct malloc_chunk *sbinptr; /* The type of bins of chunks */
typedef size_t bindex_t; /* Described below */
typedef unsigned int binmap_t; /* Described below */
typedef unsigned int flag_t; /* The type of various bit flag sets */
/* ------------------- Chunks sizes and alignments ----------------------- */
#define MCHUNK_SIZE (sizeof(mchunk))
#define CHUNK_OVERHEAD (SIZE_T_SIZE)
/* Direct chunks need a second word of overhead ... */
#define DIRECT_CHUNK_OVERHEAD (TWO_SIZE_T_SIZES)
/* ... and additional padding for fake next-chunk at foot */
#define DIRECT_FOOT_PAD (FOUR_SIZE_T_SIZES)
/* The smallest size we can malloc is an aligned minimal chunk */
#define MIN_CHUNK_SIZE\
((MCHUNK_SIZE + CHUNK_ALIGN_MASK) & ~CHUNK_ALIGN_MASK)
/* conversion from malloc headers to user pointers, and back */
#define chunk2mem(p) ((void *)((char *)(p) + TWO_SIZE_T_SIZES))
#define mem2chunk(mem) ((mchunkptr)((char *)(mem) - TWO_SIZE_T_SIZES))
/* chunk associated with aligned address A */
#define align_as_chunk(A) (mchunkptr)((A) + align_offset(chunk2mem(A)))
/* Bounds on request (not chunk) sizes. */
#define MAX_REQUEST ((~MIN_CHUNK_SIZE+1) << 2)
#define MIN_REQUEST (MIN_CHUNK_SIZE - CHUNK_OVERHEAD - SIZE_T_ONE)
/* pad request bytes into a usable size */
#define pad_request(req) \
(((req) + CHUNK_OVERHEAD + CHUNK_ALIGN_MASK) & ~CHUNK_ALIGN_MASK)
/* pad request, checking for minimum (but not maximum) */
#define request2size(req) \
(((req) < MIN_REQUEST)? MIN_CHUNK_SIZE : pad_request(req))
/* ------------------ Operations on head and foot fields ----------------- */
#define PINUSE_BIT (SIZE_T_ONE)
#define CINUSE_BIT (SIZE_T_TWO)
#define INUSE_BITS (PINUSE_BIT|CINUSE_BIT)
/* Head value for fenceposts */
#define FENCEPOST_HEAD (INUSE_BITS|SIZE_T_SIZE)
/* extraction of fields from head words */
#define cinuse(p) ((p)->head & CINUSE_BIT)
#define pinuse(p) ((p)->head & PINUSE_BIT)
#define chunksize(p) ((p)->head & ~(INUSE_BITS))
#define clear_pinuse(p) ((p)->head &= ~PINUSE_BIT)
#define clear_cinuse(p) ((p)->head &= ~CINUSE_BIT)
/* Treat space at ptr +/- offset as a chunk */
#define chunk_plus_offset(p, s) ((mchunkptr)(((char *)(p)) + (s)))
#define chunk_minus_offset(p, s) ((mchunkptr)(((char *)(p)) - (s)))
/* Ptr to next or previous physical malloc_chunk. */
#define next_chunk(p) ((mchunkptr)(((char *)(p)) + ((p)->head & ~INUSE_BITS)))
#define prev_chunk(p) ((mchunkptr)(((char *)(p)) - ((p)->prev_foot) ))
/* extract next chunk's pinuse bit */
#define next_pinuse(p) ((next_chunk(p)->head) & PINUSE_BIT)
/* Get/set size at footer */
#define get_foot(p, s) (((mchunkptr)((char *)(p) + (s)))->prev_foot)
#define set_foot(p, s) (((mchunkptr)((char *)(p) + (s)))->prev_foot = (s))
/* Set size, pinuse bit, and foot */
#define set_size_and_pinuse_of_free_chunk(p, s)\
((p)->head = (s|PINUSE_BIT), set_foot(p, s))
/* Set size, pinuse bit, foot, and clear next pinuse */
#define set_free_with_pinuse(p, s, n)\
(clear_pinuse(n), set_size_and_pinuse_of_free_chunk(p, s))
#define is_direct(p)\
(!((p)->head & PINUSE_BIT) && ((p)->prev_foot & IS_DIRECT_BIT))
/* Get the internal overhead associated with chunk p */
#define overhead_for(p)\
(is_direct(p)? DIRECT_CHUNK_OVERHEAD : CHUNK_OVERHEAD)
/* ---------------------- Overlaid data structures ----------------------- */
struct malloc_tree_chunk {
/* The first four fields must be compatible with malloc_chunk */
size_t prev_foot;
size_t head;
struct malloc_tree_chunk *fd;
struct malloc_tree_chunk *bk;
struct malloc_tree_chunk *child[2];
struct malloc_tree_chunk *parent;
bindex_t index;
};
typedef struct malloc_tree_chunk tchunk;
typedef struct malloc_tree_chunk *tchunkptr;
typedef struct malloc_tree_chunk *tbinptr; /* The type of bins of trees */
/* A little helper macro for trees */
#define leftmost_child(t) ((t)->child[0] != 0? (t)->child[0] : (t)->child[1])
/* ----------------------------- Segments -------------------------------- */
struct malloc_segment {
char *base; /* base address */
size_t size; /* allocated size */
struct malloc_segment *next; /* ptr to next segment */
};
typedef struct malloc_segment msegment;
typedef struct malloc_segment *msegmentptr;
/* ---------------------------- malloc_state ----------------------------- */
/* Bin types, widths and sizes */
#define NSMALLBINS (32U)
#define NTREEBINS (32U)
#define SMALLBIN_SHIFT (3U)
#define SMALLBIN_WIDTH (SIZE_T_ONE << SMALLBIN_SHIFT)
#define TREEBIN_SHIFT (8U)
#define MIN_LARGE_SIZE (SIZE_T_ONE << TREEBIN_SHIFT)
#define MAX_SMALL_SIZE (MIN_LARGE_SIZE - SIZE_T_ONE)
#define MAX_SMALL_REQUEST (MAX_SMALL_SIZE - CHUNK_ALIGN_MASK - CHUNK_OVERHEAD)
struct malloc_state {
binmap_t smallmap;
binmap_t treemap;
size_t dvsize;
size_t topsize;
mchunkptr dv;
mchunkptr top;
size_t trim_check;
size_t release_checks;
mchunkptr smallbins[(NSMALLBINS+1)*2];
tbinptr treebins[NTREEBINS];
msegment seg;
};
typedef struct malloc_state *mstate;
#define is_initialized(M) ((M)->top != 0)
/* -------------------------- system alloc setup ------------------------- */
/* page-align a size */
#define page_align(S)\
(((S) + (LJ_PAGESIZE - SIZE_T_ONE)) & ~(LJ_PAGESIZE - SIZE_T_ONE))
/* granularity-align a size */
#define granularity_align(S)\
(((S) + (DEFAULT_GRANULARITY - SIZE_T_ONE))\
& ~(DEFAULT_GRANULARITY - SIZE_T_ONE))
#if LJ_TARGET_WINDOWS
#define mmap_align(S) granularity_align(S)
#else
#define mmap_align(S) page_align(S)
#endif
/* True if segment S holds address A */
#define segment_holds(S, A)\
((char *)(A) >= S->base && (char *)(A) < S->base + S->size)
/* Return segment holding given address */
static msegmentptr segment_holding(mstate m, char *addr)
{
msegmentptr sp = &m->seg;
for (;;) {
if (addr >= sp->base && addr < sp->base + sp->size)
return sp;
if ((sp = sp->next) == 0)
return 0;
}
}
/* Return true if segment contains a segment link */
static int has_segment_link(mstate m, msegmentptr ss)
{
msegmentptr sp = &m->seg;
for (;;) {
if ((char *)sp >= ss->base && (char *)sp < ss->base + ss->size)
return 1;
if ((sp = sp->next) == 0)
return 0;
}
}
/*
TOP_FOOT_SIZE is padding at the end of a segment, including space
that may be needed to place segment records and fenceposts when new
noncontiguous segments are added.
*/
#define TOP_FOOT_SIZE\
(align_offset(chunk2mem(0))+pad_request(sizeof(struct malloc_segment))+MIN_CHUNK_SIZE)
/* ---------------------------- Indexing Bins ---------------------------- */
#define is_small(s) (((s) >> SMALLBIN_SHIFT) < NSMALLBINS)
#define small_index(s) ((s) >> SMALLBIN_SHIFT)
#define small_index2size(i) ((i) << SMALLBIN_SHIFT)
#define MIN_SMALL_INDEX (small_index(MIN_CHUNK_SIZE))
/* addressing by index. See above about smallbin repositioning */
#define smallbin_at(M, i) ((sbinptr)((char *)&((M)->smallbins[(i)<<1])))
#define treebin_at(M,i) (&((M)->treebins[i]))
/* assign tree index for size S to variable I */
#define compute_tree_index(S, I)\
{\
unsigned int X = (unsigned int)(S >> TREEBIN_SHIFT);\
if (X == 0) {\
I = 0;\
} else if (X > 0xFFFF) {\
I = NTREEBINS-1;\
} else {\
unsigned int K = lj_fls(X);\
I = (bindex_t)((K << 1) + ((S >> (K + (TREEBIN_SHIFT-1)) & 1)));\
}\
}
/* Bit representing maximum resolved size in a treebin at i */
#define bit_for_tree_index(i) \
(i == NTREEBINS-1)? (SIZE_T_BITSIZE-1) : (((i) >> 1) + TREEBIN_SHIFT - 2)
/* Shift placing maximum resolved bit in a treebin at i as sign bit */
#define leftshift_for_tree_index(i) \
((i == NTREEBINS-1)? 0 : \
((SIZE_T_BITSIZE-SIZE_T_ONE) - (((i) >> 1) + TREEBIN_SHIFT - 2)))
/* The size of the smallest chunk held in bin with index i */
#define minsize_for_tree_index(i) \
((SIZE_T_ONE << (((i) >> 1) + TREEBIN_SHIFT)) | \
(((size_t)((i) & SIZE_T_ONE)) << (((i) >> 1) + TREEBIN_SHIFT - 1)))
/* ------------------------ Operations on bin maps ----------------------- */
/* bit corresponding to given index */
#define idx2bit(i) ((binmap_t)(1) << (i))
/* Mark/Clear bits with given index */
#define mark_smallmap(M,i) ((M)->smallmap |= idx2bit(i))
#define clear_smallmap(M,i) ((M)->smallmap &= ~idx2bit(i))
#define smallmap_is_marked(M,i) ((M)->smallmap & idx2bit(i))
#define mark_treemap(M,i) ((M)->treemap |= idx2bit(i))
#define clear_treemap(M,i) ((M)->treemap &= ~idx2bit(i))
#define treemap_is_marked(M,i) ((M)->treemap & idx2bit(i))
/* mask with all bits to left of least bit of x on */
#define left_bits(x) ((x<<1) | (~(x<<1)+1))
/* Set cinuse bit and pinuse bit of next chunk */
#define set_inuse(M,p,s)\
((p)->head = (((p)->head & PINUSE_BIT)|s|CINUSE_BIT),\
((mchunkptr)(((char *)(p)) + (s)))->head |= PINUSE_BIT)
/* Set cinuse and pinuse of this chunk and pinuse of next chunk */
#define set_inuse_and_pinuse(M,p,s)\
((p)->head = (s|PINUSE_BIT|CINUSE_BIT),\
((mchunkptr)(((char *)(p)) + (s)))->head |= PINUSE_BIT)
/* Set size, cinuse and pinuse bit of this chunk */
#define set_size_and_pinuse_of_inuse_chunk(M, p, s)\
((p)->head = (s|PINUSE_BIT|CINUSE_BIT))
/* ----------------------- Operations on smallbins ----------------------- */
/* Link a free chunk into a smallbin */
#define insert_small_chunk(M, P, S) {\
bindex_t I = small_index(S);\
mchunkptr B = smallbin_at(M, I);\
mchunkptr F = B;\
if (!smallmap_is_marked(M, I))\
mark_smallmap(M, I);\
else\
F = B->fd;\
B->fd = P;\
F->bk = P;\
P->fd = F;\
P->bk = B;\
}
/* Unlink a chunk from a smallbin */
#define unlink_small_chunk(M, P, S) {\
mchunkptr F = P->fd;\
mchunkptr B = P->bk;\
bindex_t I = small_index(S);\
if (F == B) {\
clear_smallmap(M, I);\
} else {\
F->bk = B;\
B->fd = F;\
}\
}
/* Unlink the first chunk from a smallbin */
#define unlink_first_small_chunk(M, B, P, I) {\
mchunkptr F = P->fd;\
if (B == F) {\
clear_smallmap(M, I);\
} else {\
B->fd = F;\
F->bk = B;\
}\
}
/* Replace dv node, binning the old one */
/* Used only when dvsize known to be small */
#define replace_dv(M, P, S) {\
size_t DVS = M->dvsize;\
if (DVS != 0) {\
mchunkptr DV = M->dv;\
insert_small_chunk(M, DV, DVS);\
}\
M->dvsize = S;\
M->dv = P;\
}
/* ------------------------- Operations on trees ------------------------- */
/* Insert chunk into tree */
#define insert_large_chunk(M, X, S) {\
tbinptr *H;\
bindex_t I;\
compute_tree_index(S, I);\
H = treebin_at(M, I);\
X->index = I;\
X->child[0] = X->child[1] = 0;\
if (!treemap_is_marked(M, I)) {\
mark_treemap(M, I);\
*H = X;\
X->parent = (tchunkptr)H;\
X->fd = X->bk = X;\
} else {\
tchunkptr T = *H;\
size_t K = S << leftshift_for_tree_index(I);\
for (;;) {\
if (chunksize(T) != S) {\
tchunkptr *C = &(T->child[(K >> (SIZE_T_BITSIZE-SIZE_T_ONE)) & 1]);\
K <<= 1;\
if (*C != 0) {\
T = *C;\
} else {\
*C = X;\
X->parent = T;\
X->fd = X->bk = X;\
break;\
}\
} else {\
tchunkptr F = T->fd;\
T->fd = F->bk = X;\
X->fd = F;\
X->bk = T;\
X->parent = 0;\
break;\
}\
}\
}\
}
#define unlink_large_chunk(M, X) {\
tchunkptr XP = X->parent;\
tchunkptr R;\
if (X->bk != X) {\
tchunkptr F = X->fd;\
R = X->bk;\
F->bk = R;\
R->fd = F;\
} else {\
tchunkptr *RP;\
if (((R = *(RP = &(X->child[1]))) != 0) ||\
((R = *(RP = &(X->child[0]))) != 0)) {\
tchunkptr *CP;\
while ((*(CP = &(R->child[1])) != 0) ||\
(*(CP = &(R->child[0])) != 0)) {\
R = *(RP = CP);\
}\
*RP = 0;\
}\
}\
if (XP != 0) {\
tbinptr *H = treebin_at(M, X->index);\
if (X == *H) {\
if ((*H = R) == 0) \
clear_treemap(M, X->index);\
} else {\
if (XP->child[0] == X) \
XP->child[0] = R;\
else \
XP->child[1] = R;\
}\
if (R != 0) {\
tchunkptr C0, C1;\
R->parent = XP;\
if ((C0 = X->child[0]) != 0) {\
R->child[0] = C0;\
C0->parent = R;\
}\
if ((C1 = X->child[1]) != 0) {\
R->child[1] = C1;\
C1->parent = R;\
}\
}\
}\
}
/* Relays to large vs small bin operations */
#define insert_chunk(M, P, S)\
if (is_small(S)) { insert_small_chunk(M, P, S)\
} else { tchunkptr TP = (tchunkptr)(P); insert_large_chunk(M, TP, S); }
#define unlink_chunk(M, P, S)\
if (is_small(S)) { unlink_small_chunk(M, P, S)\
} else { tchunkptr TP = (tchunkptr)(P); unlink_large_chunk(M, TP); }
/* ----------------------- Direct-mmapping chunks ----------------------- */
static void *direct_alloc(size_t nb)
{
size_t mmsize = mmap_align(nb + SIX_SIZE_T_SIZES + CHUNK_ALIGN_MASK);
if (LJ_LIKELY(mmsize > nb)) { /* Check for wrap around 0 */
char *mm = (char *)(DIRECT_MMAP(mmsize));
if (mm != CMFAIL) {
size_t offset = align_offset(chunk2mem(mm));
size_t psize = mmsize - offset - DIRECT_FOOT_PAD;
mchunkptr p = (mchunkptr)(mm + offset);
p->prev_foot = offset | IS_DIRECT_BIT;
p->head = psize|CINUSE_BIT;
chunk_plus_offset(p, psize)->head = FENCEPOST_HEAD;
chunk_plus_offset(p, psize+SIZE_T_SIZE)->head = 0;
return chunk2mem(p);
}
}
return NULL;
}
static mchunkptr direct_resize(mchunkptr oldp, size_t nb)
{
size_t oldsize = chunksize(oldp);
if (is_small(nb)) /* Can't shrink direct regions below small size */
return NULL;
/* Keep old chunk if big enough but not too big */
if (oldsize >= nb + SIZE_T_SIZE &&
(oldsize - nb) <= (DEFAULT_GRANULARITY >> 1)) {
return oldp;
} else {
size_t offset = oldp->prev_foot & ~IS_DIRECT_BIT;
size_t oldmmsize = oldsize + offset + DIRECT_FOOT_PAD;
size_t newmmsize = mmap_align(nb + SIX_SIZE_T_SIZES + CHUNK_ALIGN_MASK);
char *cp = (char *)CALL_MREMAP((char *)oldp - offset,
oldmmsize, newmmsize, CALL_MREMAP_MV);
if (cp != CMFAIL) {
mchunkptr newp = (mchunkptr)(cp + offset);
size_t psize = newmmsize - offset - DIRECT_FOOT_PAD;
newp->head = psize|CINUSE_BIT;
chunk_plus_offset(newp, psize)->head = FENCEPOST_HEAD;
chunk_plus_offset(newp, psize+SIZE_T_SIZE)->head = 0;
return newp;
}
}
return NULL;
}
/* -------------------------- mspace management -------------------------- */
/* Initialize top chunk and its size */
static void init_top(mstate m, mchunkptr p, size_t psize)
{
/* Ensure alignment */
size_t offset = align_offset(chunk2mem(p));
p = (mchunkptr)((char *)p + offset);
psize -= offset;
m->top = p;
m->topsize = psize;
p->head = psize | PINUSE_BIT;
/* set size of fake trailing chunk holding overhead space only once */
chunk_plus_offset(p, psize)->head = TOP_FOOT_SIZE;
m->trim_check = DEFAULT_TRIM_THRESHOLD; /* reset on each update */
}
/* Initialize bins for a new mstate that is otherwise zeroed out */
static void init_bins(mstate m)
{
/* Establish circular links for smallbins */
bindex_t i;
for (i = 0; i < NSMALLBINS; i++) {
sbinptr bin = smallbin_at(m,i);
bin->fd = bin->bk = bin;
}
}
/* Allocate chunk and prepend remainder with chunk in successor base. */
static void *prepend_alloc(mstate m, char *newbase, char *oldbase, size_t nb)
{
mchunkptr p = align_as_chunk(newbase);
mchunkptr oldfirst = align_as_chunk(oldbase);
size_t psize = (size_t)((char *)oldfirst - (char *)p);
mchunkptr q = chunk_plus_offset(p, nb);
size_t qsize = psize - nb;
set_size_and_pinuse_of_inuse_chunk(m, p, nb);
/* consolidate remainder with first chunk of old base */
if (oldfirst == m->top) {
size_t tsize = m->topsize += qsize;
m->top = q;
q->head = tsize | PINUSE_BIT;
} else if (oldfirst == m->dv) {
size_t dsize = m->dvsize += qsize;
m->dv = q;
set_size_and_pinuse_of_free_chunk(q, dsize);
} else {
if (!cinuse(oldfirst)) {
size_t nsize = chunksize(oldfirst);
unlink_chunk(m, oldfirst, nsize);
oldfirst = chunk_plus_offset(oldfirst, nsize);
qsize += nsize;
}
set_free_with_pinuse(q, qsize, oldfirst);
insert_chunk(m, q, qsize);
}
return chunk2mem(p);
}
/* Add a segment to hold a new noncontiguous region */
static void add_segment(mstate m, char *tbase, size_t tsize)
{
/* Determine locations and sizes of segment, fenceposts, old top */
char *old_top = (char *)m->top;
msegmentptr oldsp = segment_holding(m, old_top);
char *old_end = oldsp->base + oldsp->size;
size_t ssize = pad_request(sizeof(struct malloc_segment));
char *rawsp = old_end - (ssize + FOUR_SIZE_T_SIZES + CHUNK_ALIGN_MASK);
size_t offset = align_offset(chunk2mem(rawsp));
char *asp = rawsp + offset;
char *csp = (asp < (old_top + MIN_CHUNK_SIZE))? old_top : asp;
mchunkptr sp = (mchunkptr)csp;
msegmentptr ss = (msegmentptr)(chunk2mem(sp));
mchunkptr tnext = chunk_plus_offset(sp, ssize);
mchunkptr p = tnext;
/* reset top to new space */
init_top(m, (mchunkptr)tbase, tsize - TOP_FOOT_SIZE);
/* Set up segment record */
set_size_and_pinuse_of_inuse_chunk(m, sp, ssize);
*ss = m->seg; /* Push current record */
m->seg.base = tbase;
m->seg.size = tsize;
m->seg.next = ss;
/* Insert trailing fenceposts */
for (;;) {
mchunkptr nextp = chunk_plus_offset(p, SIZE_T_SIZE);
p->head = FENCEPOST_HEAD;
if ((char *)(&(nextp->head)) < old_end)
p = nextp;
else
break;
}
/* Insert the rest of old top into a bin as an ordinary free chunk */
if (csp != old_top) {
mchunkptr q = (mchunkptr)old_top;
size_t psize = (size_t)(csp - old_top);
mchunkptr tn = chunk_plus_offset(q, psize);
set_free_with_pinuse(q, psize, tn);
insert_chunk(m, q, psize);
}
}
/* -------------------------- System allocation -------------------------- */
static void *alloc_sys(mstate m, size_t nb)
{
char *tbase = CMFAIL;
size_t tsize = 0;
/* Directly map large chunks */
if (LJ_UNLIKELY(nb >= DEFAULT_MMAP_THRESHOLD)) {
void *mem = direct_alloc(nb);
if (mem != 0)
return mem;
}
{
size_t req = nb + TOP_FOOT_SIZE + SIZE_T_ONE;
size_t rsize = granularity_align(req);
if (LJ_LIKELY(rsize > nb)) { /* Fail if wraps around zero */
char *mp = (char *)(CALL_MMAP(rsize));
if (mp != CMFAIL) {
tbase = mp;
tsize = rsize;
}
}
}
if (tbase != CMFAIL) {
msegmentptr sp = &m->seg;
/* Try to merge with an existing segment */
while (sp != 0 && tbase != sp->base + sp->size)
sp = sp->next;
if (sp != 0 && segment_holds(sp, m->top)) { /* append */
sp->size += tsize;
init_top(m, m->top, m->topsize + tsize);
} else {
sp = &m->seg;
while (sp != 0 && sp->base != tbase + tsize)
sp = sp->next;
if (sp != 0) {
char *oldbase = sp->base;
sp->base = tbase;
sp->size += tsize;
return prepend_alloc(m, tbase, oldbase, nb);
} else {
add_segment(m, tbase, tsize);
}
}
if (nb < m->topsize) { /* Allocate from new or extended top space */
size_t rsize = m->topsize -= nb;
mchunkptr p = m->top;
mchunkptr r = m->top = chunk_plus_offset(p, nb);
r->head = rsize | PINUSE_BIT;
set_size_and_pinuse_of_inuse_chunk(m, p, nb);
return chunk2mem(p);
}
}
return NULL;
}
/* ----------------------- system deallocation -------------------------- */
/* Unmap and unlink any mmapped segments that don't contain used chunks */
static size_t release_unused_segments(mstate m)
{
size_t released = 0;
size_t nsegs = 0;
msegmentptr pred = &m->seg;
msegmentptr sp = pred->next;
while (sp != 0) {
char *base = sp->base;
size_t size = sp->size;
msegmentptr next = sp->next;
nsegs++;
{
mchunkptr p = align_as_chunk(base);
size_t psize = chunksize(p);
/* Can unmap if first chunk holds entire segment and not pinned */
if (!cinuse(p) && (char *)p + psize >= base + size - TOP_FOOT_SIZE) {
tchunkptr tp = (tchunkptr)p;
if (p == m->dv) {
m->dv = 0;
m->dvsize = 0;
} else {
unlink_large_chunk(m, tp);
}
if (CALL_MUNMAP(base, size) == 0) {
released += size;
/* unlink obsoleted record */
sp = pred;
sp->next = next;
} else { /* back out if cannot unmap */
insert_large_chunk(m, tp, psize);
}
}
}
pred = sp;
sp = next;
}
/* Reset check counter */
m->release_checks = nsegs > MAX_RELEASE_CHECK_RATE ?
nsegs : MAX_RELEASE_CHECK_RATE;
return released;
}
static int alloc_trim(mstate m, size_t pad)
{
size_t released = 0;
if (pad < MAX_REQUEST && is_initialized(m)) {
pad += TOP_FOOT_SIZE; /* ensure enough room for segment overhead */
if (m->topsize > pad) {
/* Shrink top space in granularity-size units, keeping at least one */
size_t unit = DEFAULT_GRANULARITY;
size_t extra = ((m->topsize - pad + (unit - SIZE_T_ONE)) / unit -
SIZE_T_ONE) * unit;
msegmentptr sp = segment_holding(m, (char *)m->top);
if (sp->size >= extra &&
!has_segment_link(m, sp)) { /* can't shrink if pinned */
size_t newsize = sp->size - extra;
/* Prefer mremap, fall back to munmap */
if ((CALL_MREMAP(sp->base, sp->size, newsize, CALL_MREMAP_NOMOVE) != MFAIL) ||
(CALL_MUNMAP(sp->base + newsize, extra) == 0)) {
released = extra;
}
}
if (released != 0) {
sp->size -= released;
init_top(m, m->top, m->topsize - released);
}
}
/* Unmap any unused mmapped segments */
released += release_unused_segments(m);
/* On failure, disable autotrim to avoid repeated failed future calls */
if (released == 0 && m->topsize > m->trim_check)
m->trim_check = MAX_SIZE_T;
}
return (released != 0)? 1 : 0;
}
/* ---------------------------- malloc support --------------------------- */
/* allocate a large request from the best fitting chunk in a treebin */
static void *tmalloc_large(mstate m, size_t nb)
{
tchunkptr v = 0;
size_t rsize = ~nb+1; /* Unsigned negation */
tchunkptr t;
bindex_t idx;
compute_tree_index(nb, idx);
if ((t = *treebin_at(m, idx)) != 0) {
/* Traverse tree for this bin looking for node with size == nb */
size_t sizebits = nb << leftshift_for_tree_index(idx);
tchunkptr rst = 0; /* The deepest untaken right subtree */
for (;;) {
tchunkptr rt;
size_t trem = chunksize(t) - nb;
if (trem < rsize) {
v = t;
if ((rsize = trem) == 0)
break;
}
rt = t->child[1];
t = t->child[(sizebits >> (SIZE_T_BITSIZE-SIZE_T_ONE)) & 1];
if (rt != 0 && rt != t)
rst = rt;
if (t == 0) {
t = rst; /* set t to least subtree holding sizes > nb */
break;
}
sizebits <<= 1;
}
}
if (t == 0 && v == 0) { /* set t to root of next non-empty treebin */
binmap_t leftbits = left_bits(idx2bit(idx)) & m->treemap;
if (leftbits != 0)
t = *treebin_at(m, lj_ffs(leftbits));
}
while (t != 0) { /* find smallest of tree or subtree */
size_t trem = chunksize(t) - nb;
if (trem < rsize) {
rsize = trem;
v = t;
}
t = leftmost_child(t);
}
/* If dv is a better fit, return NULL so malloc will use it */
if (v != 0 && rsize < (size_t)(m->dvsize - nb)) {
mchunkptr r = chunk_plus_offset(v, nb);
unlink_large_chunk(m, v);
if (rsize < MIN_CHUNK_SIZE) {
set_inuse_and_pinuse(m, v, (rsize + nb));
} else {
set_size_and_pinuse_of_inuse_chunk(m, v, nb);
set_size_and_pinuse_of_free_chunk(r, rsize);
insert_chunk(m, r, rsize);
}
return chunk2mem(v);
}
return NULL;
}
/* allocate a small request from the best fitting chunk in a treebin */
static void *tmalloc_small(mstate m, size_t nb)
{
tchunkptr t, v;
mchunkptr r;
size_t rsize;
bindex_t i = lj_ffs(m->treemap);
v = t = *treebin_at(m, i);
rsize = chunksize(t) - nb;
while ((t = leftmost_child(t)) != 0) {
size_t trem = chunksize(t) - nb;
if (trem < rsize) {
rsize = trem;
v = t;
}
}
r = chunk_plus_offset(v, nb);
unlink_large_chunk(m, v);
if (rsize < MIN_CHUNK_SIZE) {
set_inuse_and_pinuse(m, v, (rsize + nb));
} else {
set_size_and_pinuse_of_inuse_chunk(m, v, nb);
set_size_and_pinuse_of_free_chunk(r, rsize);
replace_dv(m, r, rsize);
}
return chunk2mem(v);
}
/* ----------------------------------------------------------------------- */
void *lj_alloc_create(void)
{
size_t tsize = DEFAULT_GRANULARITY;
char *tbase;
INIT_MMAP();
tbase = (char *)(CALL_MMAP(tsize));
if (tbase != CMFAIL) {
size_t msize = pad_request(sizeof(struct malloc_state));
mchunkptr mn;
mchunkptr msp = align_as_chunk(tbase);
mstate m = (mstate)(chunk2mem(msp));
memset(m, 0, msize);
msp->head = (msize|PINUSE_BIT|CINUSE_BIT);
m->seg.base = tbase;
m->seg.size = tsize;
m->release_checks = MAX_RELEASE_CHECK_RATE;
init_bins(m);
mn = next_chunk(mem2chunk(m));
init_top(m, mn, (size_t)((tbase + tsize) - (char *)mn) - TOP_FOOT_SIZE);
return m;
}
return NULL;
}
void lj_alloc_destroy(void *msp)
{
mstate ms = (mstate)msp;
msegmentptr sp = &ms->seg;
while (sp != 0) {
char *base = sp->base;
size_t size = sp->size;
sp = sp->next;
CALL_MUNMAP(base, size);
}
}
static LJ_NOINLINE void *lj_alloc_malloc(void *msp, size_t nsize)
{
mstate ms = (mstate)msp;
void *mem;
size_t nb;
if (nsize <= MAX_SMALL_REQUEST) {
bindex_t idx;
binmap_t smallbits;
nb = (nsize < MIN_REQUEST)? MIN_CHUNK_SIZE : pad_request(nsize);
idx = small_index(nb);
smallbits = ms->smallmap >> idx;
if ((smallbits & 0x3U) != 0) { /* Remainderless fit to a smallbin. */
mchunkptr b, p;
idx += ~smallbits & 1; /* Uses next bin if idx empty */
b = smallbin_at(ms, idx);
p = b->fd;
unlink_first_small_chunk(ms, b, p, idx);
set_inuse_and_pinuse(ms, p, small_index2size(idx));
mem = chunk2mem(p);
return mem;
} else if (nb > ms->dvsize) {
if (smallbits != 0) { /* Use chunk in next nonempty smallbin */
mchunkptr b, p, r;
size_t rsize;
binmap_t leftbits = (smallbits << idx) & left_bits(idx2bit(idx));
bindex_t i = lj_ffs(leftbits);
b = smallbin_at(ms, i);
p = b->fd;
unlink_first_small_chunk(ms, b, p, i);
rsize = small_index2size(i) - nb;
/* Fit here cannot be remainderless if 4byte sizes */
if (SIZE_T_SIZE != 4 && rsize < MIN_CHUNK_SIZE) {
set_inuse_and_pinuse(ms, p, small_index2size(i));
} else {
set_size_and_pinuse_of_inuse_chunk(ms, p, nb);
r = chunk_plus_offset(p, nb);
set_size_and_pinuse_of_free_chunk(r, rsize);
replace_dv(ms, r, rsize);
}
mem = chunk2mem(p);
return mem;
} else if (ms->treemap != 0 && (mem = tmalloc_small(ms, nb)) != 0) {
return mem;
}
}
} else if (nsize >= MAX_REQUEST) {
nb = MAX_SIZE_T; /* Too big to allocate. Force failure (in sys alloc) */
} else {
nb = pad_request(nsize);
if (ms->treemap != 0 && (mem = tmalloc_large(ms, nb)) != 0) {
return mem;
}
}
if (nb <= ms->dvsize) {
size_t rsize = ms->dvsize - nb;
mchunkptr p = ms->dv;
if (rsize >= MIN_CHUNK_SIZE) { /* split dv */
mchunkptr r = ms->dv = chunk_plus_offset(p, nb);
ms->dvsize = rsize;
set_size_and_pinuse_of_free_chunk(r, rsize);
set_size_and_pinuse_of_inuse_chunk(ms, p, nb);
} else { /* exhaust dv */
size_t dvs = ms->dvsize;
ms->dvsize = 0;
ms->dv = 0;
set_inuse_and_pinuse(ms, p, dvs);
}
mem = chunk2mem(p);
return mem;
} else if (nb < ms->topsize) { /* Split top */
size_t rsize = ms->topsize -= nb;
mchunkptr p = ms->top;
mchunkptr r = ms->top = chunk_plus_offset(p, nb);
r->head = rsize | PINUSE_BIT;
set_size_and_pinuse_of_inuse_chunk(ms, p, nb);
mem = chunk2mem(p);
return mem;
}
return alloc_sys(ms, nb);
}
static LJ_NOINLINE void *lj_alloc_free(void *msp, void *ptr)
{
if (ptr != 0) {
mchunkptr p = mem2chunk(ptr);
mstate fm = (mstate)msp;
size_t psize = chunksize(p);
mchunkptr next = chunk_plus_offset(p, psize);
if (!pinuse(p)) {
size_t prevsize = p->prev_foot;
if ((prevsize & IS_DIRECT_BIT) != 0) {
prevsize &= ~IS_DIRECT_BIT;
psize += prevsize + DIRECT_FOOT_PAD;
CALL_MUNMAP((char *)p - prevsize, psize);
return NULL;
} else {
mchunkptr prev = chunk_minus_offset(p, prevsize);
psize += prevsize;
p = prev;
/* consolidate backward */
if (p != fm->dv) {
unlink_chunk(fm, p, prevsize);
} else if ((next->head & INUSE_BITS) == INUSE_BITS) {
fm->dvsize = psize;
set_free_with_pinuse(p, psize, next);
return NULL;
}
}
}
if (!cinuse(next)) { /* consolidate forward */
if (next == fm->top) {
size_t tsize = fm->topsize += psize;
fm->top = p;
p->head = tsize | PINUSE_BIT;
if (p == fm->dv) {
fm->dv = 0;
fm->dvsize = 0;
}
if (tsize > fm->trim_check)
alloc_trim(fm, 0);
return NULL;
} else if (next == fm->dv) {
size_t dsize = fm->dvsize += psize;
fm->dv = p;
set_size_and_pinuse_of_free_chunk(p, dsize);
return NULL;
} else {
size_t nsize = chunksize(next);
psize += nsize;
unlink_chunk(fm, next, nsize);
set_size_and_pinuse_of_free_chunk(p, psize);
if (p == fm->dv) {
fm->dvsize = psize;
return NULL;
}
}
} else {
set_free_with_pinuse(p, psize, next);
}
if (is_small(psize)) {
insert_small_chunk(fm, p, psize);
} else {
tchunkptr tp = (tchunkptr)p;
insert_large_chunk(fm, tp, psize);
if (--fm->release_checks == 0)
release_unused_segments(fm);
}
}
return NULL;
}
static LJ_NOINLINE void *lj_alloc_realloc(void *msp, void *ptr, size_t nsize)
{
if (nsize >= MAX_REQUEST) {
return NULL;
} else {
mstate m = (mstate)msp;
mchunkptr oldp = mem2chunk(ptr);
size_t oldsize = chunksize(oldp);
mchunkptr next = chunk_plus_offset(oldp, oldsize);
mchunkptr newp = 0;
size_t nb = request2size(nsize);
/* Try to either shrink or extend into top. Else malloc-copy-free */
if (is_direct(oldp)) {
newp = direct_resize(oldp, nb); /* this may return NULL. */
} else if (oldsize >= nb) { /* already big enough */
size_t rsize = oldsize - nb;
newp = oldp;
if (rsize >= MIN_CHUNK_SIZE) {
mchunkptr rem = chunk_plus_offset(newp, nb);
set_inuse(m, newp, nb);
set_inuse(m, rem, rsize);
lj_alloc_free(m, chunk2mem(rem));
}
} else if (next == m->top && oldsize + m->topsize > nb) {
/* Expand into top */
size_t newsize = oldsize + m->topsize;
size_t newtopsize = newsize - nb;
mchunkptr newtop = chunk_plus_offset(oldp, nb);
set_inuse(m, oldp, nb);
newtop->head = newtopsize |PINUSE_BIT;
m->top = newtop;
m->topsize = newtopsize;
newp = oldp;
}
if (newp != 0) {
return chunk2mem(newp);
} else {
void *newmem = lj_alloc_malloc(m, nsize);
if (newmem != 0) {
size_t oc = oldsize - overhead_for(oldp);
memcpy(newmem, ptr, oc < nsize ? oc : nsize);
lj_alloc_free(m, ptr);
}
return newmem;
}
}
}
void *lj_alloc_f(void *msp, void *ptr, size_t osize, size_t nsize)
{
(void)osize;
if (nsize == 0) {
return lj_alloc_free(msp, ptr);
} else if (ptr == NULL) {
return lj_alloc_malloc(msp, nsize);
} else {
return lj_alloc_realloc(msp, ptr, nsize);
}
}
#endif
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