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Function name typo in malloc.c
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a0d0e21e 1/* malloc.c
8d063cd8 2 *
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3 */
4
87c6202a 5/*
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6 * 'The Chamber of Records,' said Gimli. 'I guess that is where we now stand.'
7 *
cdad3b53 8 * [p.321 of _The Lord of the Rings_, II/v: "The Bridge of Khazad-Dûm"]
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9 */
10
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11/* This file contains Perl's own implementation of the malloc library.
12 * It is used if Configure decides that, on your platform, Perl's
13 * version is better than the OS's, or if you give Configure the
14 * -Dusemymalloc command-line option.
15 */
16
d31a8517 17/*
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18 Here are some notes on configuring Perl's malloc.
19
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20 There are two macros which serve as bulk disablers of advanced
21 features of this malloc: NO_FANCY_MALLOC, PLAIN_MALLOC (undef by
22 default). Look in the list of default values below to understand
23 their exact effect. Defining NO_FANCY_MALLOC returns malloc.c to the
24 state of the malloc in Perl 5.004. Additionally defining PLAIN_MALLOC
25 returns it to the state as of Perl 5.000.
26
27 Note that some of the settings below may be ignored in the code based
28 on values of other macros. The PERL_CORE symbol is only defined when
29 perl itself is being compiled (so malloc can make some assumptions
30 about perl's facilities being available to it).
31
32 Each config option has a short description, followed by its name,
33 default value, and a comment about the default (if applicable). Some
34 options take a precise value, while the others are just boolean.
35 The boolean ones are listed first.
36
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37 # Read configuration settings from malloc_cfg.h
38 HAVE_MALLOC_CFG_H undef
39
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40 # Enable code for an emergency memory pool in $^M. See perlvar.pod
41 # for a description of $^M.
b9e5552c 42 PERL_EMERGENCY_SBRK !PLAIN_MALLOC
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43
44 # Enable code for printing memory statistics.
b9e5552c 45 DEBUGGING_MSTATS !PLAIN_MALLOC
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46
47 # Move allocation info for small buckets into separate areas.
48 # Memory optimization (especially for small allocations, of the
49 # less than 64 bytes). Since perl usually makes a large number
50 # of small allocations, this is usually a win.
51 PACK_MALLOC (!PLAIN_MALLOC && !RCHECK)
52
53 # Add one page to big powers of two when calculating bucket size.
54 # This is targeted at big allocations, as are common in image
55 # processing.
56 TWO_POT_OPTIMIZE !PLAIN_MALLOC
57
58 # Use intermediate bucket sizes between powers-of-two. This is
59 # generally a memory optimization, and a (small) speed pessimization.
60 BUCKETS_ROOT2 !NO_FANCY_MALLOC
61
62 # Do not check small deallocations for bad free(). Memory
63 # and speed optimization, error reporting pessimization.
64 IGNORE_SMALL_BAD_FREE (!NO_FANCY_MALLOC && !RCHECK)
65
66 # Use table lookup to decide in which bucket a given allocation will go.
67 SMALL_BUCKET_VIA_TABLE !NO_FANCY_MALLOC
68
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69 # Use a perl-defined sbrk() instead of the (presumably broken or
70 # missing) system-supplied sbrk().
71 USE_PERL_SBRK undef
72
73 # Use system malloc() (or calloc() etc.) to emulate sbrk(). Normally
74 # only used with broken sbrk()s.
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75 PERL_SBRK_VIA_MALLOC undef
76
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77 # Which allocator to use if PERL_SBRK_VIA_MALLOC
78 SYSTEM_ALLOC(a) malloc(a)
79
9ee81ef6 80 # Minimal alignment (in bytes, should be a power of 2) of SYSTEM_ALLOC
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81 SYSTEM_ALLOC_ALIGNMENT MEM_ALIGNBYTES
82
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83 # Disable memory overwrite checking with DEBUGGING. Memory and speed
84 # optimization, error reporting pessimization.
85 NO_RCHECK undef
86
87 # Enable memory overwrite checking with DEBUGGING. Memory and speed
88 # pessimization, error reporting optimization
89 RCHECK (DEBUGGING && !NO_RCHECK)
90
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91 # Do not overwrite uninit areas with DEBUGGING. Speed
92 # optimization, error reporting pessimization
93 NO_MFILL undef
94
95 # Overwrite uninit areas with DEBUGGING. Speed
96 # pessimization, error reporting optimization
97 MALLOC_FILL (DEBUGGING && !NO_RCHECK && !NO_MFILL)
98
99 # Do not check overwritten uninit areas with DEBUGGING. Speed
100 # optimization, error reporting pessimization
101 NO_FILL_CHECK undef
102
103 # Check overwritten uninit areas with DEBUGGING. Speed
104 # pessimization, error reporting optimization
105 MALLOC_FILL_CHECK (DEBUGGING && !NO_RCHECK && !NO_FILL_CHECK)
106
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107 # Failed allocations bigger than this size croak (if
108 # PERL_EMERGENCY_SBRK is enabled) without touching $^M. See
109 # perlvar.pod for a description of $^M.
110 BIG_SIZE (1<<16) # 64K
111
112 # Starting from this power of two, add an extra page to the
113 # size of the bucket. This enables optimized allocations of sizes
114 # close to powers of 2. Note that the value is indexed at 0.
115 FIRST_BIG_POW2 15 # 32K, 16K is used too often
116
117 # Estimate of minimal memory footprint. malloc uses this value to
118 # request the most reasonable largest blocks of memory from the system.
119 FIRST_SBRK (48*1024)
120
121 # Round up sbrk()s to multiples of this.
122 MIN_SBRK 2048
123
124 # Round up sbrk()s to multiples of this percent of footprint.
125 MIN_SBRK_FRAC 3
126
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127 # Round up sbrk()s to multiples of this multiple of 1/1000 of footprint.
128 MIN_SBRK_FRAC1000 (10 * MIN_SBRK_FRAC)
129
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130 # Add this much memory to big powers of two to get the bucket size.
131 PERL_PAGESIZE 4096
132
133 # This many sbrk() discontinuities should be tolerated even
134 # from the start without deciding that sbrk() is usually
135 # discontinuous.
136 SBRK_ALLOW_FAILURES 3
137
138 # This many continuous sbrk()s compensate for one discontinuous one.
139 SBRK_FAILURE_PRICE 50
140
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141 # Some configurations may ask for 12-byte-or-so allocations which
142 # require 8-byte alignment (?!). In such situation one needs to
143 # define this to disable 12-byte bucket (will increase memory footprint)
144 STRICT_ALIGNMENT undef
145
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146 # Do not allow configuration of runtime options at runtime
147 NO_MALLOC_DYNAMIC_CFG undef
148
149 # Do not allow configuration of runtime options via $ENV{PERL_MALLOC_OPT}
150 NO_PERL_MALLOC_ENV undef
151
152 [The variable consists of ;-separated parts of the form CODE=VALUE
153 with 1-character codes F, M, f, A, P, G, d, a, c for runtime
154 configuration of FIRST_SBRK, MIN_SBRK, MIN_SBRK_FRAC1000,
155 SBRK_ALLOW_FAILURES, SBRK_FAILURE_PRICE, sbrk_goodness,
156 filldead, fillalive, fillcheck. The last 3 are for DEBUGGING
157 build, and allow switching the tests for free()ed memory read,
158 uninit memory reads, and free()ed memory write.]
159
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160 This implementation assumes that calling PerlIO_printf() does not
161 result in any memory allocation calls (used during a panic).
162
163 */
164
741df71a 165
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166#ifdef HAVE_MALLOC_CFG_H
167# include "malloc_cfg.h"
168#endif
169
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170#ifndef NO_FANCY_MALLOC
171# ifndef SMALL_BUCKET_VIA_TABLE
172# define SMALL_BUCKET_VIA_TABLE
173# endif
174# ifndef BUCKETS_ROOT2
175# define BUCKETS_ROOT2
176# endif
177# ifndef IGNORE_SMALL_BAD_FREE
178# define IGNORE_SMALL_BAD_FREE
179# endif
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180#endif
181
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182#ifndef PLAIN_MALLOC /* Bulk enable features */
183# ifndef PACK_MALLOC
184# define PACK_MALLOC
185# endif
186# ifndef TWO_POT_OPTIMIZE
187# define TWO_POT_OPTIMIZE
188# endif
b9e5552c 189# ifndef PERL_EMERGENCY_SBRK
d720c441 190# define PERL_EMERGENCY_SBRK
e8bc2b5c 191# endif
b9e5552c 192# ifndef DEBUGGING_MSTATS
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193# define DEBUGGING_MSTATS
194# endif
195#endif
196
197#define MIN_BUC_POW2 (sizeof(void*) > 4 ? 3 : 2) /* Allow for 4-byte arena. */
198#define MIN_BUCKET (MIN_BUC_POW2 * BUCKETS_PER_POW2)
199
562aee6b 200#define LOG_OF_MIN_ARENA 11
e8bc2b5c 201
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202#if defined(DEBUGGING) && !defined(NO_RCHECK)
203# define RCHECK
204#endif
205#if defined(DEBUGGING) && !defined(NO_RCHECK) && !defined(NO_MFILL) && !defined(MALLOC_FILL)
206# define MALLOC_FILL
207#endif
208#if defined(DEBUGGING) && !defined(NO_RCHECK) && !defined(NO_FILL_CHECK) && !defined(MALLOC_FILL_CHECK)
209# define MALLOC_FILL_CHECK
210#endif
211#if defined(RCHECK) && defined(IGNORE_SMALL_BAD_FREE)
212# undef IGNORE_SMALL_BAD_FREE
213#endif
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214/*
215 * malloc.c (Caltech) 2/21/82
216 * Chris Kingsley, kingsley@cit-20.
217 *
218 * This is a very fast storage allocator. It allocates blocks of a small
219 * number of different sizes, and keeps free lists of each size. Blocks that
220 * don't exactly fit are passed up to the next larger size. In this
221 * implementation, the available sizes are 2^n-4 (or 2^n-12) bytes long.
cf5c4ad8 222 * If PACK_MALLOC is defined, small blocks are 2^n bytes long.
8d063cd8 223 * This is designed for use in a program that uses vast quantities of memory,
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224 * but bombs when it runs out.
225 *
4eb8286e 226 * Modifications Copyright Ilya Zakharevich 1996-99.
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227 *
228 * Still very quick, but much more thrifty. (Std config is 10% slower
229 * than it was, and takes 67% of old heap size for typical usage.)
230 *
231 * Allocations of small blocks are now table-driven to many different
486ec47a 232 * buckets. Sizes of really big buckets are increased to accommodate
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233 * common size=power-of-2 blocks. Running-out-of-memory is made into
234 * an exception. Deeply configurable and thread-safe.
235 *
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236 */
237
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238#include "EXTERN.h"
239#define PERL_IN_MALLOC_C
240#include "perl.h"
241#if defined(PERL_IMPLICIT_CONTEXT)
cea2e8a9 242# define croak Perl_croak_nocontext
b022d2d2 243# define croak2 Perl_croak_nocontext
cea2e8a9 244# define warn Perl_warn_nocontext
b022d2d2 245# define warn2 Perl_warn_nocontext
b9e5552c 246#else
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247# define croak2 croak
248# define warn2 warn
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249#endif
250#ifdef USE_ITHREADS
22f7c9c9 251# define PERL_MAYBE_ALIVE PL_thr_key
d720c441 252#else
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253# define PERL_MAYBE_ALIVE 1
254#endif
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255
256#ifndef MUTEX_LOCK
257# define MUTEX_LOCK(l)
258#endif
259
260#ifndef MUTEX_UNLOCK
261# define MUTEX_UNLOCK(l)
262#endif
263
741df71a 264#ifndef MALLOC_LOCK
efc57feb 265# define MALLOC_LOCK MUTEX_LOCK(&PL_malloc_mutex)
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266#endif
267
268#ifndef MALLOC_UNLOCK
efc57feb 269# define MALLOC_UNLOCK MUTEX_UNLOCK(&PL_malloc_mutex)
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270#endif
271
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272# ifndef fatalcroak /* make depend */
273# define fatalcroak(mess) (write(2, (mess), strlen(mess)), exit(2))
274# endif
275
760ac839 276#ifdef DEBUGGING
e8bc2b5c 277# undef DEBUG_m
51a5ed28 278# define DEBUG_m(a) \
0b250b9e 279 STMT_START { \
22f7c9c9 280 if (PERL_MAYBE_ALIVE && PERL_GET_THX) { \
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281 dTHX; \
282 if (DEBUG_m_TEST) { \
283 PL_debug &= ~DEBUG_m_FLAG; \
284 a; \
285 PL_debug |= DEBUG_m_FLAG; \
286 } \
287 } \
0b250b9e 288 } STMT_END
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289#endif
290
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291#ifdef PERL_IMPLICIT_CONTEXT
292# define PERL_IS_ALIVE aTHX
293#else
294# define PERL_IS_ALIVE TRUE
295#endif
296
297
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298/*
299 * Layout of memory:
300 * ~~~~~~~~~~~~~~~~
301 * The memory is broken into "blocks" which occupy multiples of 2K (and
302 * generally speaking, have size "close" to a power of 2). The addresses
303 * of such *unused* blocks are kept in nextf[i] with big enough i. (nextf
304 * is an array of linked lists.) (Addresses of used blocks are not known.)
305 *
4ad56ec9 306 * Moreover, since the algorithm may try to "bite" smaller blocks out
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307 * of unused bigger ones, there are also regions of "irregular" size,
308 * managed separately, by a linked list chunk_chain.
309 *
310 * The third type of storage is the sbrk()ed-but-not-yet-used space, its
311 * end and size are kept in last_sbrk_top and sbrked_remains.
312 *
313 * Growing blocks "in place":
314 * ~~~~~~~~~~~~~~~~~~~~~~~~~
315 * The address of the block with the greatest address is kept in last_op
316 * (if not known, last_op is 0). If it is known that the memory above
317 * last_op is not continuous, or contains a chunk from chunk_chain,
318 * last_op is set to 0.
319 *
320 * The chunk with address last_op may be grown by expanding into
321 * sbrk()ed-but-not-yet-used space, or trying to sbrk() more continuous
322 * memory.
323 *
324 * Management of last_op:
325 * ~~~~~~~~~~~~~~~~~~~~~
326 *
327 * free() never changes the boundaries of blocks, so is not relevant.
328 *
329 * The only way realloc() may change the boundaries of blocks is if it
330 * grows a block "in place". However, in the case of success such a
331 * chunk is automatically last_op, and it remains last_op. In the case
332 * of failure getpages_adjacent() clears last_op.
333 *
334 * malloc() may change blocks by calling morecore() only.
335 *
336 * morecore() may create new blocks by:
337 * a) biting pieces from chunk_chain (cannot create one above last_op);
338 * b) biting a piece from an unused block (if block was last_op, this
339 * may create a chunk from chain above last_op, thus last_op is
340 * invalidated in such a case).
341 * c) biting of sbrk()ed-but-not-yet-used space. This creates
342 * a block which is last_op.
343 * d) Allocating new pages by calling getpages();
344 *
345 * getpages() creates a new block. It marks last_op at the bottom of
346 * the chunk of memory it returns.
347 *
348 * Active pages footprint:
349 * ~~~~~~~~~~~~~~~~~~~~~~
350 * Note that we do not need to traverse the lists in nextf[i], just take
351 * the first element of this list. However, we *need* to traverse the
352 * list in chunk_chain, but most the time it should be a very short one,
353 * so we do not step on a lot of pages we are not going to use.
354 *
355 * Flaws:
356 * ~~~~~
357 * get_from_bigger_buckets(): forget to increment price => Quite
358 * aggressive.
359 */
360
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361/* I don't much care whether these are defined in sys/types.h--LAW */
362
363#define u_char unsigned char
364#define u_int unsigned int
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365/*
366 * I removed the definition of u_bigint which appeared to be u_bigint = UV
367 * u_bigint was only used in TWOK_MASKED and TWOK_SHIFT
368 * where I have used PTR2UV. RMB
369 */
135863df 370#define u_short unsigned short
8d063cd8 371
562aee6b 372#if defined(RCHECK) && defined(PACK_MALLOC)
e8bc2b5c 373# undef PACK_MALLOC
cf5c4ad8 374#endif
375
8d063cd8 376/*
cf5c4ad8 377 * The description below is applicable if PACK_MALLOC is not defined.
378 *
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379 * The overhead on a block is at least 4 bytes. When free, this space
380 * contains a pointer to the next free block, and the bottom two bits must
381 * be zero. When in use, the first byte is set to MAGIC, and the second
382 * byte is the size index. The remaining bytes are for alignment.
383 * If range checking is enabled and the size of the block fits
384 * in two bytes, then the top two bytes hold the size of the requested block
385 * plus the range checking words, and the header word MINUS ONE.
386 */
387union overhead {
388 union overhead *ov_next; /* when free */
85e6fe83 389#if MEM_ALIGNBYTES > 4
c623bd54 390 double strut; /* alignment problems */
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391# if MEM_ALIGNBYTES > 8
392 char sstrut[MEM_ALIGNBYTES]; /* for the sizing */
393# endif
a687059c 394#endif
8d063cd8 395 struct {
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396/*
397 * Keep the ovu_index and ovu_magic in this order, having a char
398 * field first gives alignment indigestion in some systems, such as
399 * MachTen.
400 */
8d063cd8 401 u_char ovu_index; /* bucket # */
b72ff565 402 u_char ovu_magic; /* magic number */
8d063cd8 403#ifdef RCHECK
d0bbed78 404 /* Subtract one to fit into u_short for an extra bucket */
22f7c9c9 405 u_short ovu_size; /* block size (requested + overhead - 1) */
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406 u_int ovu_rmagic; /* range magic number */
407#endif
408 } ovu;
409#define ov_magic ovu.ovu_magic
410#define ov_index ovu.ovu_index
411#define ov_size ovu.ovu_size
412#define ov_rmagic ovu.ovu_rmagic
413};
414
415#define MAGIC 0xff /* magic # on accounting info */
416#define RMAGIC 0x55555555 /* magic # on range info */
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417#define RMAGIC_C 0x55 /* magic # on range info */
418
8d063cd8 419#ifdef RCHECK
d0bbed78 420# define RMAGIC_SZ sizeof (u_int) /* Overhead at end of bucket */
c2a5c2d2 421# ifdef TWO_POT_OPTIMIZE
22f7c9c9 422# define MAX_SHORT_BUCKET (12 * BUCKETS_PER_POW2) /* size-1 fits in short */
c2a5c2d2 423# else
e8bc2b5c 424# define MAX_SHORT_BUCKET (13 * BUCKETS_PER_POW2)
c2a5c2d2 425# endif
8d063cd8 426#else
d0bbed78 427# define RMAGIC_SZ 0
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428#endif
429
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430#if !defined(PACK_MALLOC) && defined(BUCKETS_ROOT2)
431# undef BUCKETS_ROOT2
432#endif
433
434#ifdef BUCKETS_ROOT2
435# define BUCKET_TABLE_SHIFT 2
436# define BUCKET_POW2_SHIFT 1
437# define BUCKETS_PER_POW2 2
438#else
439# define BUCKET_TABLE_SHIFT MIN_BUC_POW2
440# define BUCKET_POW2_SHIFT 0
441# define BUCKETS_PER_POW2 1
442#endif
443
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444#if !defined(MEM_ALIGNBYTES) || ((MEM_ALIGNBYTES > 4) && !defined(STRICT_ALIGNMENT))
445/* Figure out the alignment of void*. */
446struct aligner {
447 char c;
448 void *p;
449};
8c2f25b1 450# define ALIGN_SMALL ((IV)((caddr_t)&(((struct aligner*)0)->p)))
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451#else
452# define ALIGN_SMALL MEM_ALIGNBYTES
453#endif
454
455#define IF_ALIGN_8(yes,no) ((ALIGN_SMALL>4) ? (yes) : (no))
456
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457#ifdef BUCKETS_ROOT2
458# define MAX_BUCKET_BY_TABLE 13
a3b680e6 459static const u_short buck_size[MAX_BUCKET_BY_TABLE + 1] =
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460 {
461 0, 0, 0, 0, 4, 4, 8, 12, 16, 24, 32, 48, 64, 80,
462 };
d0bbed78 463# define BUCKET_SIZE_NO_SURPLUS(i) ((i) % 2 ? buck_size[i] : (1 << ((i) >> BUCKET_POW2_SHIFT)))
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464# define BUCKET_SIZE_REAL(i) ((i) <= MAX_BUCKET_BY_TABLE \
465 ? buck_size[i] \
466 : ((1 << ((i) >> BUCKET_POW2_SHIFT)) \
467 - MEM_OVERHEAD(i) \
468 + POW2_OPTIMIZE_SURPLUS(i)))
469#else
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470# define BUCKET_SIZE_NO_SURPLUS(i) (1 << ((i) >> BUCKET_POW2_SHIFT))
471# define BUCKET_SIZE(i) (BUCKET_SIZE_NO_SURPLUS(i) + POW2_OPTIMIZE_SURPLUS(i))
472# define BUCKET_SIZE_REAL(i) (BUCKET_SIZE(i) - MEM_OVERHEAD(i))
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473#endif
474
475
cf5c4ad8 476#ifdef PACK_MALLOC
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477/* In this case there are several possible layout of arenas depending
478 * on the size. Arenas are of sizes multiple to 2K, 2K-aligned, and
479 * have a size close to a power of 2.
480 *
481 * Arenas of the size >= 4K keep one chunk only. Arenas of size 2K
482 * may keep one chunk or multiple chunks. Here are the possible
483 * layouts of arenas:
484 *
485 * # One chunk only, chunksize 2^k + SOMETHING - ALIGN, k >= 11
486 *
487 * INDEX MAGIC1 UNUSED CHUNK1
488 *
489 * # Multichunk with sanity checking and chunksize 2^k-ALIGN, k>7
490 *
491 * INDEX MAGIC1 MAGIC2 MAGIC3 UNUSED CHUNK1 CHUNK2 CHUNK3 ...
492 *
493 * # Multichunk with sanity checking and size 2^k-ALIGN, k=7
494 *
495 * INDEX MAGIC1 MAGIC2 MAGIC3 UNUSED CHUNK1 UNUSED CHUNK2 CHUNK3 ...
496 *
497 * # Multichunk with sanity checking and size up to 80
498 *
499 * INDEX UNUSED MAGIC1 UNUSED MAGIC2 UNUSED ... CHUNK1 CHUNK2 CHUNK3 ...
500 *
501 * # No sanity check (usually up to 48=byte-long buckets)
502 * INDEX UNUSED CHUNK1 CHUNK2 ...
503 *
504 * Above INDEX and MAGIC are one-byte-long. Sizes of UNUSED are
505 * appropriate to keep algorithms simple and memory aligned. INDEX
506 * encodes the size of the chunk, while MAGICn encodes state (used,
507 * free or non-managed-by-us-so-it-indicates-a-bug) of CHUNKn. MAGIC
508 * is used for sanity checking purposes only. SOMETHING is 0 or 4K
486ec47a 509 * (to make size of big CHUNK accommodate allocations for powers of two
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510 * better).
511 *
512 * [There is no need to alignment between chunks, since C rules ensure
513 * that structs which need 2^k alignment have sizeof which is
514 * divisible by 2^k. Thus as far as the last chunk is aligned at the
515 * end of the arena, and 2K-alignment does not contradict things,
516 * everything is going to be OK for sizes of chunks 2^n and 2^n +
517 * 2^k. Say, 80-bit buckets will be 16-bit aligned, and as far as we
518 * put allocations for requests in 65..80 range, all is fine.
519 *
520 * Note, however, that standard malloc() puts more strict
521 * requirements than the above C rules. Moreover, our algorithms of
522 * realloc() may break this idyll, but we suppose that realloc() does
523 * need not change alignment.]
524 *
525 * Is very important to make calculation of the offset of MAGICm as
526 * quick as possible, since it is done on each malloc()/free(). In
527 * fact it is so quick that it has quite little effect on the speed of
528 * doing malloc()/free(). [By default] We forego such calculations
529 * for small chunks, but only to save extra 3% of memory, not because
530 * of speed considerations.
531 *
532 * Here is the algorithm [which is the same for all the allocations
533 * schemes above], see OV_MAGIC(block,bucket). Let OFFSETm be the
534 * offset of the CHUNKm from the start of ARENA. Then offset of
535 * MAGICm is (OFFSET1 >> SHIFT) + ADDOFFSET. Here SHIFT and ADDOFFSET
536 * are numbers which depend on the size of the chunks only.
537 *
538 * Let as check some sanity conditions. Numbers OFFSETm>>SHIFT are
539 * different for all the chunks in the arena if 2^SHIFT is not greater
540 * than size of the chunks in the arena. MAGIC1 will not overwrite
541 * INDEX provided ADDOFFSET is >0 if OFFSET1 < 2^SHIFT. MAGIClast
542 * will not overwrite CHUNK1 if OFFSET1 > (OFFSETlast >> SHIFT) +
543 * ADDOFFSET.
544 *
545 * Make SHIFT the maximal possible (there is no point in making it
546 * smaller). Since OFFSETlast is 2K - CHUNKSIZE, above restrictions
547 * give restrictions on OFFSET1 and on ADDOFFSET.
548 *
549 * In particular, for chunks of size 2^k with k>=6 we can put
550 * ADDOFFSET to be from 0 to 2^k - 2^(11-k), and have
551 * OFFSET1==chunksize. For chunks of size 80 OFFSET1 of 2K%80=48 is
552 * large enough to have ADDOFFSET between 1 and 16 (similarly for 96,
553 * when ADDOFFSET should be 1). In particular, keeping MAGICs for
554 * these sizes gives no additional size penalty.
555 *
556 * However, for chunks of size 2^k with k<=5 this gives OFFSET1 >=
557 * ADDOFSET + 2^(11-k). Keeping ADDOFFSET 0 allows for 2^(11-k)-2^(11-2k)
558 * chunks per arena. This is smaller than 2^(11-k) - 1 which are
559 * needed if no MAGIC is kept. [In fact, having a negative ADDOFFSET
560 * would allow for slightly more buckets per arena for k=2,3.]
561 *
562 * Similarly, for chunks of size 3/2*2^k with k<=5 MAGICs would span
563 * the area up to 2^(11-k)+ADDOFFSET. For k=4 this give optimal
564 * ADDOFFSET as -7..0. For k=3 ADDOFFSET can go up to 4 (with tiny
565 * savings for negative ADDOFFSET). For k=5 ADDOFFSET can go -1..16
566 * (with no savings for negative values).
cf5c4ad8 567 *
4ad56ec9
IZ
568 * In particular, keeping ADDOFFSET 0 for sizes of chunks up to 2^6
569 * leads to tiny pessimizations in case of sizes 4, 8, 12, 24, and
570 * leads to no contradictions except for size=80 (or 96.)
cf5c4ad8 571 *
4ad56ec9
IZ
572 * However, it also makes sense to keep no magic for sizes 48 or less.
573 * This is what we do. In this case one needs ADDOFFSET>=1 also for
574 * chunksizes 12, 24, and 48, unless one gets one less chunk per
575 * arena.
576 *
577 * The algo of OV_MAGIC(block,bucket) keeps ADDOFFSET 0 until
578 * chunksize of 64, then makes it 1.
cf5c4ad8 579 *
4ad56ec9
IZ
580 * This allows for an additional optimization: the above scheme leads
581 * to giant overheads for sizes 128 or more (one whole chunk needs to
582 * be sacrifised to keep INDEX). Instead we use chunks not of size
583 * 2^k, but of size 2^k-ALIGN. If we pack these chunks at the end of
584 * the arena, then the beginnings are still in different 2^k-long
585 * sections of the arena if k>=7 for ALIGN==4, and k>=8 if ALIGN=8.
586 * Thus for k>7 the above algo of calculating the offset of the magic
587 * will still give different answers for different chunks. And to
588 * avoid the overrun of MAGIC1 into INDEX, one needs ADDOFFSET of >=1.
589 * In the case k=7 we just move the first chunk an extra ALIGN
590 * backward inside the ARENA (this is done once per arena lifetime,
591 * thus is not a big overhead). */
e8bc2b5c
GS
592# define MAX_PACKED_POW2 6
593# define MAX_PACKED (MAX_PACKED_POW2 * BUCKETS_PER_POW2 + BUCKET_POW2_SHIFT)
594# define MAX_POW2_ALGO ((1<<(MAX_PACKED_POW2 + 1)) - M_OVERHEAD)
595# define TWOK_MASK ((1<<LOG_OF_MIN_ARENA) - 1)
56431972
RB
596# define TWOK_MASKED(x) (PTR2UV(x) & ~TWOK_MASK)
597# define TWOK_SHIFT(x) (PTR2UV(x) & TWOK_MASK)
598# define OV_INDEXp(block) (INT2PTR(u_char*,TWOK_MASKED(block)))
cf5c4ad8 599# define OV_INDEX(block) (*OV_INDEXp(block))
600# define OV_MAGIC(block,bucket) (*(OV_INDEXp(block) + \
e8bc2b5c
GS
601 (TWOK_SHIFT(block)>> \
602 (bucket>>BUCKET_POW2_SHIFT)) + \
603 (bucket >= MIN_NEEDS_SHIFT ? 1 : 0)))
604 /* A bucket can have a shift smaller than it size, we need to
605 shift its magic number so it will not overwrite index: */
606# ifdef BUCKETS_ROOT2
607# define MIN_NEEDS_SHIFT (7*BUCKETS_PER_POW2 - 1) /* Shift 80 greater than chunk 64. */
608# else
609# define MIN_NEEDS_SHIFT (7*BUCKETS_PER_POW2) /* Shift 128 greater than chunk 32. */
610# endif
cf5c4ad8 611# define CHUNK_SHIFT 0
612
e8bc2b5c
GS
613/* Number of active buckets of given ordinal. */
614#ifdef IGNORE_SMALL_BAD_FREE
615#define FIRST_BUCKET_WITH_CHECK (6 * BUCKETS_PER_POW2) /* 64 */
616# define N_BLKS(bucket) ( (bucket) < FIRST_BUCKET_WITH_CHECK \
d0bbed78 617 ? ((1<<LOG_OF_MIN_ARENA) - 1)/BUCKET_SIZE_NO_SURPLUS(bucket) \
e8bc2b5c
GS
618 : n_blks[bucket] )
619#else
620# define N_BLKS(bucket) n_blks[bucket]
621#endif
622
a3b680e6 623static const u_short n_blks[LOG_OF_MIN_ARENA * BUCKETS_PER_POW2] =
e8bc2b5c
GS
624 {
625# if BUCKETS_PER_POW2==1
626 0, 0,
627 (MIN_BUC_POW2==2 ? 384 : 0),
628 224, 120, 62, 31, 16, 8, 4, 2
629# else
630 0, 0, 0, 0,
631 (MIN_BUC_POW2==2 ? 384 : 0), (MIN_BUC_POW2==2 ? 384 : 0), /* 4, 4 */
632 224, 149, 120, 80, 62, 41, 31, 25, 16, 16, 8, 8, 4, 4, 2, 2
633# endif
634 };
635
636/* Shift of the first bucket with the given ordinal inside 2K chunk. */
637#ifdef IGNORE_SMALL_BAD_FREE
638# define BLK_SHIFT(bucket) ( (bucket) < FIRST_BUCKET_WITH_CHECK \
639 ? ((1<<LOG_OF_MIN_ARENA) \
d0bbed78 640 - BUCKET_SIZE_NO_SURPLUS(bucket) * N_BLKS(bucket)) \
e8bc2b5c
GS
641 : blk_shift[bucket])
642#else
643# define BLK_SHIFT(bucket) blk_shift[bucket]
644#endif
645
a3b680e6 646static const u_short blk_shift[LOG_OF_MIN_ARENA * BUCKETS_PER_POW2] =
e8bc2b5c
GS
647 {
648# if BUCKETS_PER_POW2==1
649 0, 0,
650 (MIN_BUC_POW2==2 ? 512 : 0),
651 256, 128, 64, 64, /* 8 to 64 */
652 16*sizeof(union overhead),
653 8*sizeof(union overhead),
654 4*sizeof(union overhead),
655 2*sizeof(union overhead),
656# else
657 0, 0, 0, 0,
658 (MIN_BUC_POW2==2 ? 512 : 0), (MIN_BUC_POW2==2 ? 512 : 0),
659 256, 260, 128, 128, 64, 80, 64, 48, /* 8 to 96 */
660 16*sizeof(union overhead), 16*sizeof(union overhead),
661 8*sizeof(union overhead), 8*sizeof(union overhead),
662 4*sizeof(union overhead), 4*sizeof(union overhead),
663 2*sizeof(union overhead), 2*sizeof(union overhead),
664# endif
665 };
cf5c4ad8 666
5bbd1ef5
IZ
667# define NEEDED_ALIGNMENT 0x800 /* 2k boundaries */
668# define WANTED_ALIGNMENT 0x800 /* 2k boundaries */
669
cf5c4ad8 670#else /* !PACK_MALLOC */
671
672# define OV_MAGIC(block,bucket) (block)->ov_magic
673# define OV_INDEX(block) (block)->ov_index
674# define CHUNK_SHIFT 1
e8bc2b5c 675# define MAX_PACKED -1
5bbd1ef5
IZ
676# define NEEDED_ALIGNMENT MEM_ALIGNBYTES
677# define WANTED_ALIGNMENT 0x400 /* 1k boundaries */
678
cf5c4ad8 679#endif /* !PACK_MALLOC */
680
d0bbed78 681#define M_OVERHEAD (sizeof(union overhead) + RMAGIC_SZ) /* overhead at start+end */
e8bc2b5c
GS
682
683#ifdef PACK_MALLOC
684# define MEM_OVERHEAD(bucket) \
685 (bucket <= MAX_PACKED ? 0 : M_OVERHEAD)
686# ifdef SMALL_BUCKET_VIA_TABLE
687# define START_SHIFTS_BUCKET ((MAX_PACKED_POW2 + 1) * BUCKETS_PER_POW2)
688# define START_SHIFT MAX_PACKED_POW2
689# ifdef BUCKETS_ROOT2 /* Chunks of size 3*2^n. */
690# define SIZE_TABLE_MAX 80
691# else
692# define SIZE_TABLE_MAX 64
693# endif
a3b680e6 694static const char bucket_of[] =
e8bc2b5c
GS
695 {
696# ifdef BUCKETS_ROOT2 /* Chunks of size 3*2^n. */
697 /* 0 to 15 in 4-byte increments. */
698 (sizeof(void*) > 4 ? 6 : 5), /* 4/8, 5-th bucket for better reports */
699 6, /* 8 */
274c7500 700 IF_ALIGN_8(8,7), 8, /* 16/12, 16 */
e8bc2b5c
GS
701 9, 9, 10, 10, /* 24, 32 */
702 11, 11, 11, 11, /* 48 */
703 12, 12, 12, 12, /* 64 */
704 13, 13, 13, 13, /* 80 */
705 13, 13, 13, 13 /* 80 */
706# else /* !BUCKETS_ROOT2 */
707 /* 0 to 15 in 4-byte increments. */
708 (sizeof(void*) > 4 ? 3 : 2),
709 3,
710 4, 4,
711 5, 5, 5, 5,
712 6, 6, 6, 6,
713 6, 6, 6, 6
714# endif /* !BUCKETS_ROOT2 */
715 };
716# else /* !SMALL_BUCKET_VIA_TABLE */
717# define START_SHIFTS_BUCKET MIN_BUCKET
718# define START_SHIFT (MIN_BUC_POW2 - 1)
719# endif /* !SMALL_BUCKET_VIA_TABLE */
720#else /* !PACK_MALLOC */
721# define MEM_OVERHEAD(bucket) M_OVERHEAD
722# ifdef SMALL_BUCKET_VIA_TABLE
723# undef SMALL_BUCKET_VIA_TABLE
724# endif
725# define START_SHIFTS_BUCKET MIN_BUCKET
726# define START_SHIFT (MIN_BUC_POW2 - 1)
727#endif /* !PACK_MALLOC */
cf5c4ad8 728
8d063cd8 729/*
55497cff 730 * Big allocations are often of the size 2^n bytes. To make them a
731 * little bit better, make blocks of size 2^n+pagesize for big n.
732 */
733
734#ifdef TWO_POT_OPTIMIZE
735
5f05dabc 736# ifndef PERL_PAGESIZE
737# define PERL_PAGESIZE 4096
738# endif
e8bc2b5c
GS
739# ifndef FIRST_BIG_POW2
740# define FIRST_BIG_POW2 15 /* 32K, 16K is used too often. */
5f05dabc 741# endif
e8bc2b5c 742# define FIRST_BIG_BLOCK (1<<FIRST_BIG_POW2)
55497cff 743/* If this value or more, check against bigger blocks. */
744# define FIRST_BIG_BOUND (FIRST_BIG_BLOCK - M_OVERHEAD)
745/* If less than this value, goes into 2^n-overhead-block. */
746# define LAST_SMALL_BOUND ((FIRST_BIG_BLOCK>>1) - M_OVERHEAD)
747
e8bc2b5c
GS
748# define POW2_OPTIMIZE_ADJUST(nbytes) \
749 ((nbytes >= FIRST_BIG_BOUND) ? nbytes -= PERL_PAGESIZE : 0)
750# define POW2_OPTIMIZE_SURPLUS(bucket) \
751 ((bucket >= FIRST_BIG_POW2 * BUCKETS_PER_POW2) ? PERL_PAGESIZE : 0)
752
753#else /* !TWO_POT_OPTIMIZE */
754# define POW2_OPTIMIZE_ADJUST(nbytes)
755# define POW2_OPTIMIZE_SURPLUS(bucket) 0
756#endif /* !TWO_POT_OPTIMIZE */
757
b9e5552c 758#ifdef HAS_64K_LIMIT
e8bc2b5c
GS
759# define BARK_64K_LIMIT(what,nbytes,size) \
760 if (nbytes > 0xffff) { \
761 PerlIO_printf(PerlIO_stderr(), \
762 "%s too large: %lx\n", what, size); \
763 my_exit(1); \
764 }
b9e5552c 765#else /* !HAS_64K_LIMIT */
e8bc2b5c 766# define BARK_64K_LIMIT(what,nbytes,size)
b9e5552c 767#endif /* !HAS_64K_LIMIT */
55497cff 768
e8bc2b5c
GS
769#ifndef MIN_SBRK
770# define MIN_SBRK 2048
771#endif
772
773#ifndef FIRST_SBRK
d720c441 774# define FIRST_SBRK (48*1024)
e8bc2b5c
GS
775#endif
776
777/* Minimal sbrk in percents of what is already alloced. */
778#ifndef MIN_SBRK_FRAC
779# define MIN_SBRK_FRAC 3
780#endif
781
782#ifndef SBRK_ALLOW_FAILURES
783# define SBRK_ALLOW_FAILURES 3
784#endif
55497cff 785
e8bc2b5c
GS
786#ifndef SBRK_FAILURE_PRICE
787# define SBRK_FAILURE_PRICE 50
55497cff 788#endif
789
5aaab254 790static void morecore (int bucket);
24dd13bf 791# if defined(DEBUGGING)
9dbded1f 792static void botch (const char *diag, const char *s, const char *file, int line);
24dd13bf
JH
793# endif
794static void add_to_chain (void *p, MEM_SIZE size, MEM_SIZE chip);
795static void* get_from_chain (MEM_SIZE size);
796static void* get_from_bigger_buckets(int bucket, MEM_SIZE size);
797static union overhead *getpages (MEM_SIZE needed, int *nblksp, int bucket);
798static int getpages_adjacent(MEM_SIZE require);
799
3541dd58 800#ifdef I_MACH_CTHREADS
772fe5b3
HM
801# undef MUTEX_LOCK
802# define MUTEX_LOCK(m) STMT_START { if (*m) mutex_lock(*m); } STMT_END
803# undef MUTEX_UNLOCK
804# define MUTEX_UNLOCK(m) STMT_START { if (*m) mutex_unlock(*m); } STMT_END
3541dd58
HM
805#endif
806
22f7c9c9
JH
807#ifndef PTRSIZE
808# define PTRSIZE sizeof(void*)
809#endif
810
b022d2d2
IZ
811#ifndef BITS_IN_PTR
812# define BITS_IN_PTR (8*PTRSIZE)
813#endif
814
815/*
816 * nextf[i] is the pointer to the next free block of size 2^i. The
817 * smallest allocatable block is 8 bytes. The overhead information
818 * precedes the data area returned to the user.
819 */
820#define NBUCKETS (BITS_IN_PTR*BUCKETS_PER_POW2 + 1)
821static union overhead *nextf[NBUCKETS];
822
823#if defined(PURIFY) && !defined(USE_PERL_SBRK)
824# define USE_PERL_SBRK
825#endif
826
827#ifdef USE_PERL_SBRK
3f270f98 828# define sbrk(a) Perl_sbrk(a)
b022d2d2 829Malloc_t Perl_sbrk (int size);
b022d2d2 830#else
3f270f98 831# ifndef HAS_SBRK_PROTO /* <unistd.h> usually takes care of this */
b022d2d2 832extern Malloc_t sbrk(int);
3f270f98 833# endif
ef9f17be 834#endif
b022d2d2 835
22f7c9c9
JH
836#ifndef MIN_SBRK_FRAC1000 /* Backward compatibility */
837# define MIN_SBRK_FRAC1000 (MIN_SBRK_FRAC * 10)
838#endif
839
840#ifndef START_EXTERN_C
841# ifdef __cplusplus
842# define START_EXTERN_C extern "C" {
843# else
844# define START_EXTERN_C
845# endif
846#endif
847
848#ifndef END_EXTERN_C
849# ifdef __cplusplus
850# define END_EXTERN_C };
851# else
852# define END_EXTERN_C
853# endif
854#endif
855
856#include "malloc_ctl.h"
857
858#ifndef NO_MALLOC_DYNAMIC_CFG
859# define PERL_MALLOC_OPT_CHARS "FMfAPGdac"
860
41ad8e42
JH
861# ifndef FILL_DEAD_DEFAULT
862# define FILL_DEAD_DEFAULT 1
863# endif
864# ifndef FILL_ALIVE_DEFAULT
865# define FILL_ALIVE_DEFAULT 1
866# endif
867# ifndef FILL_CHECK_DEFAULT
868# define FILL_CHECK_DEFAULT 1
869# endif
870
22f7c9c9
JH
871static IV MallocCfg[MallocCfg_last] = {
872 FIRST_SBRK,
873 MIN_SBRK,
874 MIN_SBRK_FRAC,
875 SBRK_ALLOW_FAILURES,
876 SBRK_FAILURE_PRICE,
877 SBRK_ALLOW_FAILURES * SBRK_FAILURE_PRICE, /* sbrk_goodness */
41ad8e42
JH
878 FILL_DEAD_DEFAULT, /* FILL_DEAD */
879 FILL_ALIVE_DEFAULT, /* FILL_ALIVE */
880 FILL_CHECK_DEFAULT, /* FILL_CHECK */
22f7c9c9
JH
881 0, /* MallocCfg_skip_cfg_env */
882 0, /* MallocCfg_cfg_env_read */
883 0, /* MallocCfg_emergency_buffer_size */
884 0, /* MallocCfg_emergency_buffer_prepared_size */
885 0 /* MallocCfg_emergency_buffer_last_req */
886};
887IV *MallocCfg_ptr = MallocCfg;
888
6af660ee
IZ
889static char* MallocCfgP[MallocCfg_last] = {
890 0, /* MallocCfgP_emergency_buffer */
891 0, /* MallocCfgP_emergency_buffer_prepared */
892};
893char **MallocCfgP_ptr = MallocCfgP;
894
22f7c9c9
JH
895# undef MIN_SBRK
896# undef FIRST_SBRK
897# undef MIN_SBRK_FRAC1000
898# undef SBRK_ALLOW_FAILURES
899# undef SBRK_FAILURE_PRICE
900
901# define MIN_SBRK MallocCfg[MallocCfg_MIN_SBRK]
902# define FIRST_SBRK MallocCfg[MallocCfg_FIRST_SBRK]
903# define MIN_SBRK_FRAC1000 MallocCfg[MallocCfg_MIN_SBRK_FRAC1000]
904# define SBRK_ALLOW_FAILURES MallocCfg[MallocCfg_SBRK_ALLOW_FAILURES]
905# define SBRK_FAILURE_PRICE MallocCfg[MallocCfg_SBRK_FAILURE_PRICE]
906
907# define sbrk_goodness MallocCfg[MallocCfg_sbrk_goodness]
908
909# define emergency_buffer_size MallocCfg[MallocCfg_emergency_buffer_size]
910# define emergency_buffer_last_req MallocCfg[MallocCfg_emergency_buffer_last_req]
911
912# define FILL_DEAD MallocCfg[MallocCfg_filldead]
913# define FILL_ALIVE MallocCfg[MallocCfg_fillalive]
914# define FILL_CHECK_CFG MallocCfg[MallocCfg_fillcheck]
915# define FILL_CHECK (FILL_DEAD && FILL_CHECK_CFG)
916
6af660ee
IZ
917# define emergency_buffer MallocCfgP[MallocCfgP_emergency_buffer]
918# define emergency_buffer_prepared MallocCfgP[MallocCfgP_emergency_buffer_prepared]
919
22f7c9c9
JH
920#else /* defined(NO_MALLOC_DYNAMIC_CFG) */
921
922# define FILL_DEAD 1
923# define FILL_ALIVE 1
924# define FILL_CHECK 1
925static int sbrk_goodness = SBRK_ALLOW_FAILURES * SBRK_FAILURE_PRICE;
926
927# define NO_PERL_MALLOC_ENV
928
929#endif
930
b022d2d2
IZ
931#ifdef DEBUGGING_MSTATS
932/*
933 * nmalloc[i] is the difference between the number of mallocs and frees
934 * for a given block size.
935 */
936static u_int nmalloc[NBUCKETS];
937static u_int sbrk_slack;
938static u_int start_slack;
939#else /* !( defined DEBUGGING_MSTATS ) */
940# define sbrk_slack 0
941#endif
942
943static u_int goodsbrk;
944
22f7c9c9 945#ifdef PERL_EMERGENCY_SBRK
febabd2a
DD
946
947# ifndef BIG_SIZE
948# define BIG_SIZE (1<<16) /* 64K */
949# endif
950
22f7c9c9 951# ifdef NO_MALLOC_DYNAMIC_CFG
55497cff 952static MEM_SIZE emergency_buffer_size;
22f7c9c9
JH
953 /* 0 if the last request for more memory succeeded.
954 Otherwise the size of the failing request. */
955static MEM_SIZE emergency_buffer_last_req;
6af660ee
IZ
956static char *emergency_buffer;
957static char *emergency_buffer_prepared;
22f7c9c9
JH
958# endif
959
960# ifndef emergency_sbrk_croak
961# define emergency_sbrk_croak croak2
962# endif
963
22f7c9c9
JH
964static char *
965perl_get_emergency_buffer(IV *size)
966{
967 dTHX;
968 /* First offense, give a possibility to recover by dieing. */
969 /* No malloc involved here: */
22f7c9c9
JH
970 SV *sv;
971 char *pv;
a4fc7abc 972 GV **gvp = (GV**)hv_fetchs(PL_defstash, "^M", FALSE);
22f7c9c9 973
a4fc7abc 974 if (!gvp) gvp = (GV**)hv_fetchs(PL_defstash, "\015", FALSE);
22f7c9c9
JH
975 if (!gvp || !(sv = GvSV(*gvp)) || !SvPOK(sv)
976 || (SvLEN(sv) < (1<<LOG_OF_MIN_ARENA) - M_OVERHEAD))
977 return NULL; /* Now die die die... */
978 /* Got it, now detach SvPV: */
4b1c440c 979 pv = SvPV_nolen(sv);
22f7c9c9
JH
980 /* Check alignment: */
981 if ((PTR2UV(pv) - sizeof(union overhead)) & (NEEDED_ALIGNMENT - 1)) {
982 PerlIO_puts(PerlIO_stderr(),"Bad alignment of $^M!\n");
983 return NULL; /* die die die */
984 }
985
986 SvPOK_off(sv);
bd61b366 987 SvPV_set(sv, NULL);
87a1ef3d
SP
988 SvCUR_set(sv, 0);
989 SvLEN_set(sv, 0);
22f7c9c9
JH
990 *size = malloced_size(pv) + M_OVERHEAD;
991 return pv - sizeof(union overhead);
992}
b9e5552c 993# define PERL_GET_EMERGENCY_BUFFER(p) perl_get_emergency_buffer(p)
22f7c9c9
JH
994
995# ifndef NO_MALLOC_DYNAMIC_CFG
996static char *
997get_emergency_buffer(IV *size)
998{
999 char *pv = emergency_buffer_prepared;
1000
1001 *size = MallocCfg[MallocCfg_emergency_buffer_prepared_size];
1002 emergency_buffer_prepared = 0;
1003 MallocCfg[MallocCfg_emergency_buffer_prepared_size] = 0;
1004 return pv;
1005}
1006
1007/* Returns 0 on success, -1 on bad alignment, -2 if not implemented */
1008int
1009set_emergency_buffer(char *b, IV size)
1010{
1011 if (PTR2UV(b) & (NEEDED_ALIGNMENT - 1))
1012 return -1;
1013 if (MallocCfg[MallocCfg_emergency_buffer_prepared_size])
1014 add_to_chain((void*)emergency_buffer_prepared,
1015 MallocCfg[MallocCfg_emergency_buffer_prepared_size], 0);
1016 emergency_buffer_prepared = b;
1017 MallocCfg[MallocCfg_emergency_buffer_prepared_size] = size;
1018 return 0;
1019}
1020# define GET_EMERGENCY_BUFFER(p) get_emergency_buffer(p)
1021# else /* NO_MALLOC_DYNAMIC_CFG */
1022# define GET_EMERGENCY_BUFFER(p) NULL
1023int
1024set_emergency_buffer(char *b, IV size)
1025{
1026 return -1;
1027}
1028# endif
55497cff 1029
cea2e8a9
GS
1030static Malloc_t
1031emergency_sbrk(MEM_SIZE size)
55497cff 1032{
28ac10b1
IZ
1033 MEM_SIZE rsize = (((size - 1)>>LOG_OF_MIN_ARENA) + 1)<<LOG_OF_MIN_ARENA;
1034
22f7c9c9 1035 if (size >= BIG_SIZE
575fbe19
SH
1036 && (!emergency_buffer_last_req ||
1037 (size < (MEM_SIZE)emergency_buffer_last_req))) {
b022d2d2 1038 /* Give the possibility to recover, but avoid an infinite cycle. */
741df71a 1039 MALLOC_UNLOCK;
22f7c9c9
JH
1040 emergency_buffer_last_req = size;
1041 emergency_sbrk_croak("Out of memory during \"large\" request for %"UVuf" bytes, total sbrk() is %"UVuf" bytes", (UV)size, (UV)(goodsbrk + sbrk_slack));
55497cff 1042 }
1043
575fbe19 1044 if ((MEM_SIZE)emergency_buffer_size >= rsize) {
28ac10b1
IZ
1045 char *old = emergency_buffer;
1046
1047 emergency_buffer_size -= rsize;
1048 emergency_buffer += rsize;
1049 return old;
1050 } else {
55497cff 1051 /* First offense, give a possibility to recover by dieing. */
1052 /* No malloc involved here: */
22f7c9c9
JH
1053 IV Size;
1054 char *pv = GET_EMERGENCY_BUFFER(&Size);
28ac10b1 1055 int have = 0;
55497cff 1056
28ac10b1
IZ
1057 if (emergency_buffer_size) {
1058 add_to_chain(emergency_buffer, emergency_buffer_size, 0);
1059 emergency_buffer_size = 0;
bd61b366 1060 emergency_buffer = NULL;
28ac10b1
IZ
1061 have = 1;
1062 }
22f7c9c9
JH
1063
1064 if (!pv)
1065 pv = PERL_GET_EMERGENCY_BUFFER(&Size);
1066 if (!pv) {
28ac10b1
IZ
1067 if (have)
1068 goto do_croak;
55497cff 1069 return (char *)-1; /* Now die die die... */
28ac10b1 1070 }
22f7c9c9 1071
55497cff 1072 /* Check alignment: */
22f7c9c9
JH
1073 if (PTR2UV(pv) & (NEEDED_ALIGNMENT - 1)) {
1074 dTHX;
1075
55497cff 1076 PerlIO_puts(PerlIO_stderr(),"Bad alignment of $^M!\n");
bbce6d69 1077 return (char *)-1; /* die die die */
55497cff 1078 }
1079
22f7c9c9
JH
1080 emergency_buffer = pv;
1081 emergency_buffer_size = Size;
55497cff 1082 }
28ac10b1 1083 do_croak:
741df71a 1084 MALLOC_UNLOCK;
22f7c9c9 1085 emergency_sbrk_croak("Out of memory during request for %"UVuf" bytes, total sbrk() is %"UVuf" bytes", (UV)size, (UV)(goodsbrk + sbrk_slack));
118e2215 1086 assert(0); /* NOTREACHED */
bd61b366 1087 return NULL;
55497cff 1088}
1089
22f7c9c9 1090#else /* !defined(PERL_EMERGENCY_SBRK) */
55497cff 1091# define emergency_sbrk(size) -1
22f7c9c9
JH
1092#endif /* defined PERL_EMERGENCY_SBRK */
1093
7cd83f65
CB
1094/* Don't use PerlIO buffered writes as they allocate memory. */
1095#define MYMALLOC_WRITE2STDERR(s) PerlLIO_write(PerlIO_fileno(PerlIO_stderr()),s,strlen(s))
55497cff 1096
760ac839 1097#ifdef DEBUGGING
3541dd58 1098#undef ASSERT
e7e7e0a5
DM
1099#define ASSERT(p,diag) if (!(p)) botch(diag,STRINGIFY(p),__FILE__,__LINE__);
1100
cea2e8a9 1101static void
9dbded1f 1102botch(const char *diag, const char *s, const char *file, int line)
8d063cd8 1103{
899be101 1104 dVAR;
9dbded1f 1105 dTHX;
22f7c9c9
JH
1106 if (!(PERL_MAYBE_ALIVE && PERL_GET_THX))
1107 goto do_write;
1108 else {
22f7c9c9 1109 if (PerlIO_printf(PerlIO_stderr(),
67920cb2 1110 "assertion botched (%s?): %s %s:%d\n",
066d1a89 1111 diag, s, file, line) != 0) {
22f7c9c9 1112 do_write: /* Can be initializing interpreter */
7cd83f65
CB
1113 MYMALLOC_WRITE2STDERR("assertion botched (");
1114 MYMALLOC_WRITE2STDERR(diag);
1115 MYMALLOC_WRITE2STDERR("?): ");
1116 MYMALLOC_WRITE2STDERR(s);
1117 MYMALLOC_WRITE2STDERR(" (");
1118 MYMALLOC_WRITE2STDERR(file);
1119 MYMALLOC_WRITE2STDERR(":");
6bf964e1
JH
1120 {
1121 char linebuf[10];
1122 char *s = linebuf + sizeof(linebuf) - 1;
1123 int n = line;
1124 *s = 0;
1125 do {
1126 *--s = '0' + (n % 10);
1127 } while (n /= 10);
7cd83f65 1128 MYMALLOC_WRITE2STDERR(s);
6bf964e1 1129 }
7cd83f65 1130 MYMALLOC_WRITE2STDERR(")\n");
22f7c9c9 1131 }
3028581b 1132 PerlProc_abort();
22f7c9c9 1133 }
8d063cd8
LW
1134}
1135#else
3541dd58 1136#define ASSERT(p, diag)
8d063cd8
LW
1137#endif
1138
22f7c9c9
JH
1139#ifdef MALLOC_FILL
1140/* Fill should be long enough to cover long */
1141static void
1142fill_pat_4bytes(unsigned char *s, size_t nbytes, const unsigned char *fill)
1143{
1144 unsigned char *e = s + nbytes;
1145 long *lp;
b464bac0 1146 const long lfill = *(long*)fill;
22f7c9c9
JH
1147
1148 if (PTR2UV(s) & (sizeof(long)-1)) { /* Align the pattern */
1149 int shift = sizeof(long) - (PTR2UV(s) & (sizeof(long)-1));
1150 unsigned const char *f = fill + sizeof(long) - shift;
1151 unsigned char *e1 = s + shift;
1152
1153 while (s < e1)
1154 *s++ = *f++;
1155 }
1156 lp = (long*)s;
1157 while ((unsigned char*)(lp + 1) <= e)
1158 *lp++ = lfill;
1159 s = (unsigned char*)lp;
1160 while (s < e)
1161 *s++ = *fill++;
1162}
1163/* Just malloc()ed */
1164static const unsigned char fill_feedadad[] =
1165 {0xFE, 0xED, 0xAD, 0xAD, 0xFE, 0xED, 0xAD, 0xAD,
1166 0xFE, 0xED, 0xAD, 0xAD, 0xFE, 0xED, 0xAD, 0xAD};
1167/* Just free()ed */
1168static const unsigned char fill_deadbeef[] =
1169 {0xDE, 0xAD, 0xBE, 0xEF, 0xDE, 0xAD, 0xBE, 0xEF,
1170 0xDE, 0xAD, 0xBE, 0xEF, 0xDE, 0xAD, 0xBE, 0xEF};
1171# define FILL_DEADBEEF(s, n) \
1172 (void)(FILL_DEAD? (fill_pat_4bytes((s), (n), fill_deadbeef), 0) : 0)
1173# define FILL_FEEDADAD(s, n) \
1174 (void)(FILL_ALIVE? (fill_pat_4bytes((s), (n), fill_feedadad), 0) : 0)
1175#else
1176# define FILL_DEADBEEF(s, n) ((void)0)
1177# define FILL_FEEDADAD(s, n) ((void)0)
1178# undef MALLOC_FILL_CHECK
1179#endif
1180
1181#ifdef MALLOC_FILL_CHECK
1182static int
1183cmp_pat_4bytes(unsigned char *s, size_t nbytes, const unsigned char *fill)
1184{
1185 unsigned char *e = s + nbytes;
1186 long *lp;
b464bac0 1187 const long lfill = *(long*)fill;
22f7c9c9
JH
1188
1189 if (PTR2UV(s) & (sizeof(long)-1)) { /* Align the pattern */
1190 int shift = sizeof(long) - (PTR2UV(s) & (sizeof(long)-1));
1191 unsigned const char *f = fill + sizeof(long) - shift;
1192 unsigned char *e1 = s + shift;
1193
1194 while (s < e1)
1195 if (*s++ != *f++)
1196 return 1;
1197 }
1198 lp = (long*)s;
1199 while ((unsigned char*)(lp + 1) <= e)
1200 if (*lp++ != lfill)
1201 return 1;
1202 s = (unsigned char*)lp;
1203 while (s < e)
1204 if (*s++ != *fill++)
1205 return 1;
1206 return 0;
1207}
1208# define FILLCHECK_DEADBEEF(s, n) \
1209 ASSERT(!FILL_CHECK || !cmp_pat_4bytes(s, n, fill_deadbeef), \
1210 "free()ed/realloc()ed-away memory was overwritten")
1211#else
1212# define FILLCHECK_DEADBEEF(s, n) ((void)0)
1213#endif
1214
64107180 1215int
0eccc83d 1216S_adjust_size_and_find_bucket(size_t *nbytes_p)
8d063cd8 1217{
64107180
NC
1218 MEM_SIZE shiftr;
1219 int bucket;
1220 size_t nbytes = *nbytes_p;
45d8adaa 1221
8d063cd8
LW
1222 /*
1223 * Convert amount of memory requested into
1224 * closest block size stored in hash buckets
1225 * which satisfies request. Account for
1226 * space used per block for accounting.
1227 */
cf5c4ad8 1228#ifdef PACK_MALLOC
e8bc2b5c
GS
1229# ifdef SMALL_BUCKET_VIA_TABLE
1230 if (nbytes == 0)
1231 bucket = MIN_BUCKET;
1232 else if (nbytes <= SIZE_TABLE_MAX) {
1233 bucket = bucket_of[(nbytes - 1) >> BUCKET_TABLE_SHIFT];
1234 } else
1235# else
043bf814
RB
1236 if (nbytes == 0)
1237 nbytes = 1;
e8bc2b5c
GS
1238 if (nbytes <= MAX_POW2_ALGO) goto do_shifts;
1239 else
1240# endif
55497cff 1241#endif
e8bc2b5c
GS
1242 {
1243 POW2_OPTIMIZE_ADJUST(nbytes);
1244 nbytes += M_OVERHEAD;
1245 nbytes = (nbytes + 3) &~ 3;
516a5887 1246#if defined(PACK_MALLOC) && !defined(SMALL_BUCKET_VIA_TABLE)
e8bc2b5c 1247 do_shifts:
516a5887 1248#endif
e8bc2b5c
GS
1249 shiftr = (nbytes - 1) >> START_SHIFT;
1250 bucket = START_SHIFTS_BUCKET;
1251 /* apart from this loop, this is O(1) */
1252 while (shiftr >>= 1)
1253 bucket += BUCKETS_PER_POW2;
cf5c4ad8 1254 }
64107180
NC
1255 *nbytes_p = nbytes;
1256 return bucket;
1257}
1258
1259Malloc_t
1260Perl_malloc(size_t nbytes)
1261{
1262 dVAR;
eb578fdb
KW
1263 union overhead *p;
1264 int bucket;
64107180
NC
1265
1266#if defined(DEBUGGING) || defined(RCHECK)
1267 MEM_SIZE size = nbytes;
1268#endif
1269
1270 BARK_64K_LIMIT("Allocation",nbytes,nbytes);
1271#ifdef DEBUGGING
1272 if ((long)nbytes < 0)
1273 croak("%s", "panic: malloc");
1274#endif
1275
0eccc83d 1276 bucket = S_adjust_size_and_find_bucket(&nbytes);
4ad56ec9 1277 MALLOC_LOCK;
8d063cd8
LW
1278 /*
1279 * If nothing in hash bucket right now,
1280 * request more memory from the system.
1281 */
1282 if (nextf[bucket] == NULL)
1283 morecore(bucket);
e8bc2b5c 1284 if ((p = nextf[bucket]) == NULL) {
741df71a 1285 MALLOC_UNLOCK;
0b250b9e
GS
1286 {
1287 dTHX;
1288 if (!PL_nomemok) {
febabd2a 1289#if defined(PLAIN_MALLOC) && defined(NO_FANCY_MALLOC)
7cd83f65 1290 MYMALLOC_WRITE2STDERR("Out of memory!\n");
febabd2a 1291#else
b022d2d2
IZ
1292 char buff[80];
1293 char *eb = buff + sizeof(buff) - 1;
1294 char *s = eb;
1295 size_t n = nbytes;
1296
7cd83f65 1297 MYMALLOC_WRITE2STDERR("Out of memory during request for ");
b022d2d2
IZ
1298#if defined(DEBUGGING) || defined(RCHECK)
1299 n = size;
1300#endif
1301 *s = 0;
1302 do {
1303 *--s = '0' + (n % 10);
1304 } while (n /= 10);
7cd83f65
CB
1305 MYMALLOC_WRITE2STDERR(s);
1306 MYMALLOC_WRITE2STDERR(" bytes, total sbrk() is ");
b022d2d2
IZ
1307 s = eb;
1308 n = goodsbrk + sbrk_slack;
1309 do {
1310 *--s = '0' + (n % 10);
1311 } while (n /= 10);
7cd83f65
CB
1312 MYMALLOC_WRITE2STDERR(s);
1313 MYMALLOC_WRITE2STDERR(" bytes!\n");
febabd2a 1314#endif /* defined(PLAIN_MALLOC) && defined(NO_FANCY_MALLOC) */
0b250b9e
GS
1315 my_exit(1);
1316 }
ee0007ab 1317 }
4ad56ec9 1318 return (NULL);
45d8adaa
LW
1319 }
1320
8d063cd8 1321 /* remove from linked list */
22f7c9c9
JH
1322#ifdef DEBUGGING
1323 if ( (PTR2UV(p) & (MEM_ALIGNBYTES - 1))
1324 /* Can't get this low */
1325 || (p && PTR2UV(p) < (1<<LOG_OF_MIN_ARENA)) ) {
e8cd8248 1326 dTHX;
b900a521 1327 PerlIO_printf(PerlIO_stderr(),
7fa2f4f1
GS
1328 "Unaligned pointer in the free chain 0x%"UVxf"\n",
1329 PTR2UV(p));
1330 }
22f7c9c9
JH
1331 if ( (PTR2UV(p->ov_next) & (MEM_ALIGNBYTES - 1))
1332 || (p->ov_next && PTR2UV(p->ov_next) < (1<<LOG_OF_MIN_ARENA)) ) {
e8cd8248 1333 dTHX;
7fa2f4f1 1334 PerlIO_printf(PerlIO_stderr(),
a0288114 1335 "Unaligned \"next\" pointer in the free "
d2560b70 1336 "chain 0x%"UVxf" at 0x%"UVxf"\n",
7fa2f4f1 1337 PTR2UV(p->ov_next), PTR2UV(p));
32e30700 1338 }
bf38876a
LW
1339#endif
1340 nextf[bucket] = p->ov_next;
4ad56ec9
IZ
1341
1342 MALLOC_UNLOCK;
1343
51a5ed28
HS
1344 DEBUG_m(PerlIO_printf(Perl_debug_log,
1345 "0x%"UVxf": (%05lu) malloc %ld bytes\n",
253fdc3f 1346 PTR2UV((Malloc_t)(p + CHUNK_SHIFT)), (unsigned long)(PL_an++),
51a5ed28
HS
1347 (long)size));
1348
22f7c9c9 1349 FILLCHECK_DEADBEEF((unsigned char*)(p + CHUNK_SHIFT),
d0bbed78 1350 BUCKET_SIZE_REAL(bucket) + RMAGIC_SZ);
22f7c9c9 1351
e8bc2b5c
GS
1352#ifdef IGNORE_SMALL_BAD_FREE
1353 if (bucket >= FIRST_BUCKET_WITH_CHECK)
1354#endif
1355 OV_MAGIC(p, bucket) = MAGIC;
cf5c4ad8 1356#ifndef PACK_MALLOC
1357 OV_INDEX(p) = bucket;
1358#endif
8d063cd8
LW
1359#ifdef RCHECK
1360 /*
1361 * Record allocated size of block and
1362 * bound space with magic numbers.
1363 */
8d063cd8 1364 p->ov_rmagic = RMAGIC;
e8bc2b5c
GS
1365 if (bucket <= MAX_SHORT_BUCKET) {
1366 int i;
1367
1368 nbytes = size + M_OVERHEAD;
1369 p->ov_size = nbytes - 1;
d0bbed78
IZ
1370 if ((i = nbytes & (RMAGIC_SZ-1))) {
1371 i = RMAGIC_SZ - i;
1372 while (i--) /* nbytes - RMAGIC_SZ is end of alloced area */
1373 ((caddr_t)p + nbytes - RMAGIC_SZ)[i] = RMAGIC_C;
e8bc2b5c 1374 }
d0bbed78
IZ
1375 /* Same at RMAGIC_SZ-aligned RMAGIC */
1376 nbytes = (nbytes + RMAGIC_SZ - 1) & ~(RMAGIC_SZ - 1);
1377 ((u_int *)((caddr_t)p + nbytes))[-1] = RMAGIC;
e8bc2b5c 1378 }
22f7c9c9 1379 FILL_FEEDADAD((unsigned char *)(p + CHUNK_SHIFT), size);
8d063cd8 1380#endif
cf5c4ad8 1381 return ((Malloc_t)(p + CHUNK_SHIFT));
8d063cd8
LW
1382}
1383
e8bc2b5c
GS
1384static char *last_sbrk_top;
1385static char *last_op; /* This arena can be easily extended. */
6e21dc91 1386static MEM_SIZE sbrked_remains;
e8bc2b5c
GS
1387
1388#ifdef DEBUGGING_MSTATS
1389static int sbrks;
1390#endif
1391
1392struct chunk_chain_s {
1393 struct chunk_chain_s *next;
1394 MEM_SIZE size;
1395};
1396static struct chunk_chain_s *chunk_chain;
1397static int n_chunks;
1398static char max_bucket;
1399
1400/* Cutoff a piece of one of the chunks in the chain. Prefer smaller chunk. */
cea2e8a9
GS
1401static void *
1402get_from_chain(MEM_SIZE size)
e8bc2b5c
GS
1403{
1404 struct chunk_chain_s *elt = chunk_chain, **oldp = &chunk_chain;
1405 struct chunk_chain_s **oldgoodp = NULL;
1406 long min_remain = LONG_MAX;
1407
1408 while (elt) {
1409 if (elt->size >= size) {
1410 long remains = elt->size - size;
1411 if (remains >= 0 && remains < min_remain) {
1412 oldgoodp = oldp;
1413 min_remain = remains;
1414 }
1415 if (remains == 0) {
1416 break;
1417 }
1418 }
1419 oldp = &( elt->next );
1420 elt = elt->next;
1421 }
1422 if (!oldgoodp) return NULL;
1423 if (min_remain) {
1424 void *ret = *oldgoodp;
1425 struct chunk_chain_s *next = (*oldgoodp)->next;
1426
1427 *oldgoodp = (struct chunk_chain_s *)((char*)ret + size);
1428 (*oldgoodp)->size = min_remain;
1429 (*oldgoodp)->next = next;
1430 return ret;
1431 } else {
1432 void *ret = *oldgoodp;
1433 *oldgoodp = (*oldgoodp)->next;
1434 n_chunks--;
1435 return ret;
1436 }
1437}
1438
cea2e8a9
GS
1439static void
1440add_to_chain(void *p, MEM_SIZE size, MEM_SIZE chip)
e8bc2b5c
GS
1441{
1442 struct chunk_chain_s *next = chunk_chain;
1443 char *cp = (char*)p;
1444
1445 cp += chip;
1446 chunk_chain = (struct chunk_chain_s *)cp;
1447 chunk_chain->size = size - chip;
1448 chunk_chain->next = next;
1449 n_chunks++;
1450}
1451
cea2e8a9
GS
1452static void *
1453get_from_bigger_buckets(int bucket, MEM_SIZE size)
e8bc2b5c
GS
1454{
1455 int price = 1;
1456 static int bucketprice[NBUCKETS];
1457 while (bucket <= max_bucket) {
1458 /* We postpone stealing from bigger buckets until we want it
1459 often enough. */
1460 if (nextf[bucket] && bucketprice[bucket]++ >= price) {
1461 /* Steal it! */
1462 void *ret = (void*)(nextf[bucket] - 1 + CHUNK_SHIFT);
1463 bucketprice[bucket] = 0;
1464 if (((char*)nextf[bucket]) - M_OVERHEAD == last_op) {
1465 last_op = NULL; /* Disable optimization */
1466 }
1467 nextf[bucket] = nextf[bucket]->ov_next;
1468#ifdef DEBUGGING_MSTATS
1469 nmalloc[bucket]--;
1470 start_slack -= M_OVERHEAD;
1471#endif
d0bbed78 1472 add_to_chain(ret, (BUCKET_SIZE_NO_SURPLUS(bucket) +
e8bc2b5c
GS
1473 POW2_OPTIMIZE_SURPLUS(bucket)),
1474 size);
1475 return ret;
1476 }
1477 bucket++;
1478 }
1479 return NULL;
1480}
1481
cea2e8a9 1482static union overhead *
c7374474 1483getpages(MEM_SIZE needed, int *nblksp, int bucket)
fa423c5b 1484{
899be101 1485 dVAR;
fa423c5b
IZ
1486 /* Need to do (possibly expensive) system call. Try to
1487 optimize it for rare calling. */
1488 MEM_SIZE require = needed - sbrked_remains;
1489 char *cp;
1490 union overhead *ovp;
c7374474 1491 MEM_SIZE slack = 0;
fa423c5b 1492
22f7c9c9 1493 if (sbrk_goodness > 0) {
575fbe19 1494 if (!last_sbrk_top && require < (MEM_SIZE)FIRST_SBRK)
fa423c5b 1495 require = FIRST_SBRK;
575fbe19 1496 else if (require < (MEM_SIZE)MIN_SBRK) require = MIN_SBRK;
fa423c5b 1497
8c2f25b1 1498 if (require < (Size_t)(goodsbrk * MIN_SBRK_FRAC1000 / 1000))
22f7c9c9 1499 require = goodsbrk * MIN_SBRK_FRAC1000 / 1000;
fa423c5b
IZ
1500 require = ((require - 1 + MIN_SBRK) / MIN_SBRK) * MIN_SBRK;
1501 } else {
1502 require = needed;
1503 last_sbrk_top = 0;
1504 sbrked_remains = 0;
1505 }
1506
1507 DEBUG_m(PerlIO_printf(Perl_debug_log,
1508 "sbrk(%ld) for %ld-byte-long arena\n",
1509 (long)require, (long) needed));
1510 cp = (char *)sbrk(require);
1511#ifdef DEBUGGING_MSTATS
1512 sbrks++;
1513#endif
1514 if (cp == last_sbrk_top) {
1515 /* Common case, anything is fine. */
22f7c9c9 1516 sbrk_goodness++;
fa423c5b 1517 ovp = (union overhead *) (cp - sbrked_remains);
e9397286 1518 last_op = cp - sbrked_remains;
fa423c5b
IZ
1519 sbrked_remains = require - (needed - sbrked_remains);
1520 } else if (cp == (char *)-1) { /* no more room! */
1521 ovp = (union overhead *)emergency_sbrk(needed);
1522 if (ovp == (union overhead *)-1)
1523 return 0;
e9397286
GS
1524 if (((char*)ovp) > last_op) { /* Cannot happen with current emergency_sbrk() */
1525 last_op = 0;
1526 }
fa423c5b
IZ
1527 return ovp;
1528 } else { /* Non-continuous or first sbrk(). */
1529 long add = sbrked_remains;
1530 char *newcp;
1531
1532 if (sbrked_remains) { /* Put rest into chain, we
1533 cannot use it right now. */
1534 add_to_chain((void*)(last_sbrk_top - sbrked_remains),
1535 sbrked_remains, 0);
1536 }
1537
1538 /* Second, check alignment. */
1539 slack = 0;
1540
5bbd1ef5
IZ
1541 /* WANTED_ALIGNMENT may be more than NEEDED_ALIGNMENT, but this may
1542 improve performance of memory access. */
56431972
RB
1543 if (PTR2UV(cp) & (WANTED_ALIGNMENT - 1)) { /* Not aligned. */
1544 slack = WANTED_ALIGNMENT - (PTR2UV(cp) & (WANTED_ALIGNMENT - 1));
fa423c5b
IZ
1545 add += slack;
1546 }
fa423c5b
IZ
1547
1548 if (add) {
1549 DEBUG_m(PerlIO_printf(Perl_debug_log,
1550 "sbrk(%ld) to fix non-continuous/off-page sbrk:\n\t%ld for alignement,\t%ld were assumed to come from the tail of the previous sbrk\n",
1551 (long)add, (long) slack,
1552 (long) sbrked_remains));
1553 newcp = (char *)sbrk(add);
1554#if defined(DEBUGGING_MSTATS)
1555 sbrks++;
1556 sbrk_slack += add;
1557#endif
1558 if (newcp != cp + require) {
1559 /* Too bad: even rounding sbrk() is not continuous.*/
1560 DEBUG_m(PerlIO_printf(Perl_debug_log,
1561 "failed to fix bad sbrk()\n"));
1562#ifdef PACK_MALLOC
1563 if (slack) {
741df71a 1564 MALLOC_UNLOCK;
5bbd1ef5 1565 fatalcroak("panic: Off-page sbrk\n");
fa423c5b
IZ
1566 }
1567#endif
1568 if (sbrked_remains) {
1569 /* Try again. */
1570#if defined(DEBUGGING_MSTATS)
1571 sbrk_slack += require;
1572#endif
1573 require = needed;
1574 DEBUG_m(PerlIO_printf(Perl_debug_log,
1575 "straight sbrk(%ld)\n",
1576 (long)require));
1577 cp = (char *)sbrk(require);
1578#ifdef DEBUGGING_MSTATS
1579 sbrks++;
1580#endif
1581 if (cp == (char *)-1)
1582 return 0;
1583 }
22f7c9c9 1584 sbrk_goodness = -1; /* Disable optimization!
fa423c5b
IZ
1585 Continue with not-aligned... */
1586 } else {
1587 cp += slack;
1588 require += sbrked_remains;
1589 }
1590 }
1591
1592 if (last_sbrk_top) {
22f7c9c9 1593 sbrk_goodness -= SBRK_FAILURE_PRICE;
fa423c5b
IZ
1594 }
1595
1596 ovp = (union overhead *) cp;
1597 /*
1598 * Round up to minimum allocation size boundary
1599 * and deduct from block count to reflect.
1600 */
1601
5bbd1ef5 1602# if NEEDED_ALIGNMENT > MEM_ALIGNBYTES
56431972 1603 if (PTR2UV(ovp) & (NEEDED_ALIGNMENT - 1))
5bbd1ef5
IZ
1604 fatalcroak("Misalignment of sbrk()\n");
1605 else
1606# endif
56431972 1607 if (PTR2UV(ovp) & (MEM_ALIGNBYTES - 1)) {
fa423c5b 1608 DEBUG_m(PerlIO_printf(Perl_debug_log,
486ec47a 1609 "fixing sbrk(): %d bytes off machine alignment\n",
56431972
RB
1610 (int)(PTR2UV(ovp) & (MEM_ALIGNBYTES - 1))));
1611 ovp = INT2PTR(union overhead *,(PTR2UV(ovp) + MEM_ALIGNBYTES) &
5bbd1ef5 1612 (MEM_ALIGNBYTES - 1));
fa423c5b
IZ
1613 (*nblksp)--;
1614# if defined(DEBUGGING_MSTATS)
1615 /* This is only approx. if TWO_POT_OPTIMIZE: */
5bbd1ef5 1616 sbrk_slack += (1 << (bucket >> BUCKET_POW2_SHIFT));
fa423c5b
IZ
1617# endif
1618 }
a0288114 1619 ; /* Finish "else" */
fa423c5b 1620 sbrked_remains = require - needed;
e9397286 1621 last_op = cp;
fa423c5b 1622 }
febabd2a 1623#if !defined(PLAIN_MALLOC) && !defined(NO_FANCY_MALLOC)
22f7c9c9 1624 emergency_buffer_last_req = 0;
febabd2a 1625#endif
fa423c5b 1626 last_sbrk_top = cp + require;
fa423c5b
IZ
1627#ifdef DEBUGGING_MSTATS
1628 goodsbrk += require;
1629#endif
1630 return ovp;
1631}
1632
cea2e8a9 1633static int
c7374474 1634getpages_adjacent(MEM_SIZE require)
fa423c5b
IZ
1635{
1636 if (require <= sbrked_remains) {
1637 sbrked_remains -= require;
1638 } else {
1639 char *cp;
1640
1641 require -= sbrked_remains;
1642 /* We do not try to optimize sbrks here, we go for place. */
1643 cp = (char*) sbrk(require);
1644#ifdef DEBUGGING_MSTATS
1645 sbrks++;
1646 goodsbrk += require;
1647#endif
1648 if (cp == last_sbrk_top) {
1649 sbrked_remains = 0;
1650 last_sbrk_top = cp + require;
1651 } else {
28ac10b1
IZ
1652 if (cp == (char*)-1) { /* Out of memory */
1653#ifdef DEBUGGING_MSTATS
1654 goodsbrk -= require;
1655#endif
1656 return 0;
1657 }
fa423c5b
IZ
1658 /* Report the failure: */
1659 if (sbrked_remains)
1660 add_to_chain((void*)(last_sbrk_top - sbrked_remains),
1661 sbrked_remains, 0);
1662 add_to_chain((void*)cp, require, 0);
22f7c9c9 1663 sbrk_goodness -= SBRK_FAILURE_PRICE;
fa423c5b
IZ
1664 sbrked_remains = 0;
1665 last_sbrk_top = 0;
1666 last_op = 0;
1667 return 0;
1668 }
1669 }
1670
1671 return 1;
1672}
1673
8d063cd8
LW
1674/*
1675 * Allocate more memory to the indicated bucket.
1676 */
cea2e8a9 1677static void
5aaab254 1678morecore(int bucket)
8d063cd8 1679{
899be101 1680 dVAR;
eb578fdb
KW
1681 union overhead *ovp;
1682 int rnu; /* 2^rnu bytes will be requested */
fa423c5b 1683 int nblks; /* become nblks blocks of the desired size */
eb578fdb 1684 MEM_SIZE siz, needed;
22f7c9c9 1685 static int were_called = 0;
8d063cd8
LW
1686
1687 if (nextf[bucket])
1688 return;
22f7c9c9
JH
1689#ifndef NO_PERL_MALLOC_ENV
1690 if (!were_called) {
1691 /* It's the our first time. Initialize ourselves */
1692 were_called = 1; /* Avoid a loop */
1693 if (!MallocCfg[MallocCfg_skip_cfg_env]) {
1694 char *s = getenv("PERL_MALLOC_OPT"), *t = s, *off;
1695 const char *opts = PERL_MALLOC_OPT_CHARS;
1696 int changed = 0;
1697
1698 while ( t && t[0] && t[1] == '='
1699 && ((off = strchr(opts, *t))) ) {
1700 IV val = 0;
1701
1702 t += 2;
1703 while (*t <= '9' && *t >= '0')
1704 val = 10*val + *t++ - '0';
1705 if (!*t || *t == ';') {
1706 if (MallocCfg[off - opts] != val)
1707 changed = 1;
1708 MallocCfg[off - opts] = val;
1709 if (*t)
1710 t++;
1711 }
1712 }
1713 if (t && *t) {
89229eb4 1714 dTHX;
7cd83f65
CB
1715 MYMALLOC_WRITE2STDERR("Unrecognized part of PERL_MALLOC_OPT: \"");
1716 MYMALLOC_WRITE2STDERR(t);
1717 MYMALLOC_WRITE2STDERR("\"\n");
22f7c9c9
JH
1718 }
1719 if (changed)
1720 MallocCfg[MallocCfg_cfg_env_read] = 1;
1721 }
1722 }
1723#endif
e8bc2b5c 1724 if (bucket == sizeof(MEM_SIZE)*8*BUCKETS_PER_POW2) {
741df71a 1725 MALLOC_UNLOCK;
d720c441 1726 croak("%s", "Out of memory during ridiculously large request");
55497cff 1727 }
d720c441 1728 if (bucket > max_bucket)
e8bc2b5c 1729 max_bucket = bucket;
d720c441 1730
e8bc2b5c
GS
1731 rnu = ( (bucket <= (LOG_OF_MIN_ARENA << BUCKET_POW2_SHIFT))
1732 ? LOG_OF_MIN_ARENA
1733 : (bucket >> BUCKET_POW2_SHIFT) );
1734 /* This may be overwritten later: */
1735 nblks = 1 << (rnu - (bucket >> BUCKET_POW2_SHIFT)); /* how many blocks to get */
1736 needed = ((MEM_SIZE)1 << rnu) + POW2_OPTIMIZE_SURPLUS(bucket);
1737 if (nextf[rnu << BUCKET_POW2_SHIFT]) { /* 2048b bucket. */
1738 ovp = nextf[rnu << BUCKET_POW2_SHIFT] - 1 + CHUNK_SHIFT;
1739 nextf[rnu << BUCKET_POW2_SHIFT]
1740 = nextf[rnu << BUCKET_POW2_SHIFT]->ov_next;
1741#ifdef DEBUGGING_MSTATS
1742 nmalloc[rnu << BUCKET_POW2_SHIFT]--;
1743 start_slack -= M_OVERHEAD;
1744#endif
1745 DEBUG_m(PerlIO_printf(Perl_debug_log,
1746 "stealing %ld bytes from %ld arena\n",
1747 (long) needed, (long) rnu << BUCKET_POW2_SHIFT));
1748 } else if (chunk_chain
1749 && (ovp = (union overhead*) get_from_chain(needed))) {
1750 DEBUG_m(PerlIO_printf(Perl_debug_log,
1751 "stealing %ld bytes from chain\n",
1752 (long) needed));
d720c441
IZ
1753 } else if ( (ovp = (union overhead*)
1754 get_from_bigger_buckets((rnu << BUCKET_POW2_SHIFT) + 1,
1755 needed)) ) {
e8bc2b5c
GS
1756 DEBUG_m(PerlIO_printf(Perl_debug_log,
1757 "stealing %ld bytes from bigger buckets\n",
1758 (long) needed));
1759 } else if (needed <= sbrked_remains) {
1760 ovp = (union overhead *)(last_sbrk_top - sbrked_remains);
1761 sbrked_remains -= needed;
1762 last_op = (char*)ovp;
fa423c5b
IZ
1763 } else
1764 ovp = getpages(needed, &nblks, bucket);
e8bc2b5c 1765
fa423c5b
IZ
1766 if (!ovp)
1767 return;
22f7c9c9 1768 FILL_DEADBEEF((unsigned char*)ovp, needed);
e8bc2b5c 1769
8d063cd8
LW
1770 /*
1771 * Add new memory allocated to that on
1772 * free list for this hash bucket.
1773 */
d0bbed78 1774 siz = BUCKET_SIZE_NO_SURPLUS(bucket); /* No surplus if nblks > 1 */
cf5c4ad8 1775#ifdef PACK_MALLOC
72aaf631 1776 *(u_char*)ovp = bucket; /* Fill index. */
e8bc2b5c
GS
1777 if (bucket <= MAX_PACKED) {
1778 ovp = (union overhead *) ((char*)ovp + BLK_SHIFT(bucket));
1779 nblks = N_BLKS(bucket);
cf5c4ad8 1780# ifdef DEBUGGING_MSTATS
e8bc2b5c 1781 start_slack += BLK_SHIFT(bucket);
cf5c4ad8 1782# endif
e8bc2b5c
GS
1783 } else if (bucket < LOG_OF_MIN_ARENA * BUCKETS_PER_POW2) {
1784 ovp = (union overhead *) ((char*)ovp + BLK_SHIFT(bucket));
cf5c4ad8 1785 siz -= sizeof(union overhead);
72aaf631 1786 } else ovp++; /* One chunk per block. */
e8bc2b5c 1787#endif /* PACK_MALLOC */
72aaf631 1788 nextf[bucket] = ovp;
5f05dabc 1789#ifdef DEBUGGING_MSTATS
1790 nmalloc[bucket] += nblks;
e8bc2b5c
GS
1791 if (bucket > MAX_PACKED) {
1792 start_slack += M_OVERHEAD * nblks;
1793 }
5f05dabc 1794#endif
22f7c9c9 1795
8d063cd8 1796 while (--nblks > 0) {
72aaf631
MB
1797 ovp->ov_next = (union overhead *)((caddr_t)ovp + siz);
1798 ovp = (union overhead *)((caddr_t)ovp + siz);
8d063cd8 1799 }
8595d6f1 1800 /* Not all sbrks return zeroed memory.*/
72aaf631 1801 ovp->ov_next = (union overhead *)NULL;
cf5c4ad8 1802#ifdef PACK_MALLOC
e8bc2b5c
GS
1803 if (bucket == 7*BUCKETS_PER_POW2) { /* Special case, explanation is above. */
1804 union overhead *n_op = nextf[7*BUCKETS_PER_POW2]->ov_next;
1805 nextf[7*BUCKETS_PER_POW2] =
1806 (union overhead *)((caddr_t)nextf[7*BUCKETS_PER_POW2]
1807 - sizeof(union overhead));
1808 nextf[7*BUCKETS_PER_POW2]->ov_next = n_op;
cf5c4ad8 1809 }
1810#endif /* !PACK_MALLOC */
8d063cd8
LW
1811}
1812
94b6baf5 1813Free_t
667e2948 1814Perl_mfree(Malloc_t where)
cea2e8a9 1815{
899be101 1816 dVAR;
eb578fdb
KW
1817 MEM_SIZE size;
1818 union overhead *ovp;
667e2948 1819 char *cp = (char*)where;
cf5c4ad8 1820#ifdef PACK_MALLOC
1821 u_char bucket;
1822#endif
8d063cd8 1823
e8bc2b5c 1824 DEBUG_m(PerlIO_printf(Perl_debug_log,
b900a521
JH
1825 "0x%"UVxf": (%05lu) free\n",
1826 PTR2UV(cp), (unsigned long)(PL_an++)));
45d8adaa 1827
cf5c4ad8 1828 if (cp == NULL)
1829 return;
22f7c9c9
JH
1830#ifdef DEBUGGING
1831 if (PTR2UV(cp) & (MEM_ALIGNBYTES - 1))
1832 croak("%s", "wrong alignment in free()");
1833#endif
72aaf631 1834 ovp = (union overhead *)((caddr_t)cp
e8bc2b5c 1835 - sizeof (union overhead) * CHUNK_SHIFT);
cf5c4ad8 1836#ifdef PACK_MALLOC
72aaf631 1837 bucket = OV_INDEX(ovp);
cf5c4ad8 1838#endif
e8bc2b5c
GS
1839#ifdef IGNORE_SMALL_BAD_FREE
1840 if ((bucket >= FIRST_BUCKET_WITH_CHECK)
1841 && (OV_MAGIC(ovp, bucket) != MAGIC))
1842#else
1843 if (OV_MAGIC(ovp, bucket) != MAGIC)
1844#endif
1845 {
68dc0745 1846 static int bad_free_warn = -1;
cf5c4ad8 1847 if (bad_free_warn == -1) {
e8cd8248 1848 dTHX;
5fd9e9a4 1849 char *pbf = PerlEnv_getenv("PERL_BADFREE");
cf5c4ad8 1850 bad_free_warn = (pbf) ? atoi(pbf) : 1;
1851 }
1852 if (!bad_free_warn)
1853 return;
8990e307 1854#ifdef RCHECK
e8cd8248
GS
1855 {
1856 dTHX;
9b387841
NC
1857 if (!PERL_IS_ALIVE || !PL_curcop)
1858 Perl_ck_warner_d(aTHX_ packWARN(WARN_MALLOC), "%s free() ignored (RMAGIC, PERL_CORE)",
1859 ovp->ov_rmagic == RMAGIC - 1 ?
1860 "Duplicate" : "Bad");
2ba999ec 1861 }
e476b1b5 1862#else
2ba999ec
GS
1863 {
1864 dTHX;
9b387841
NC
1865 if (!PERL_IS_ALIVE || !PL_curcop)
1866 Perl_ck_warner_d(aTHX_ packWARN(WARN_MALLOC), "%s", "Bad free() ignored (PERL_CORE)");
2ba999ec 1867 }
e476b1b5 1868#endif
8d063cd8 1869 return; /* sanity */
e8bc2b5c 1870 }
8d063cd8 1871#ifdef RCHECK
3541dd58 1872 ASSERT(ovp->ov_rmagic == RMAGIC, "chunk's head overwrite");
e8bc2b5c
GS
1873 if (OV_INDEX(ovp) <= MAX_SHORT_BUCKET) {
1874 int i;
1875 MEM_SIZE nbytes = ovp->ov_size + 1;
1876
d0bbed78
IZ
1877 if ((i = nbytes & (RMAGIC_SZ-1))) {
1878 i = RMAGIC_SZ - i;
1879 while (i--) { /* nbytes - RMAGIC_SZ is end of alloced area */
1880 ASSERT(((caddr_t)ovp + nbytes - RMAGIC_SZ)[i] == RMAGIC_C,
1881 "chunk's tail overwrite");
e8bc2b5c
GS
1882 }
1883 }
d0bbed78
IZ
1884 /* Same at RMAGIC_SZ-aligned RMAGIC */
1885 nbytes = (nbytes + (RMAGIC_SZ-1)) & ~(RMAGIC_SZ-1);
1886 ASSERT(((u_int *)((caddr_t)ovp + nbytes))[-1] == RMAGIC,
1887 "chunk's tail overwrite");
1888 FILLCHECK_DEADBEEF((unsigned char*)((caddr_t)ovp + nbytes),
1889 BUCKET_SIZE(OV_INDEX(ovp)) - nbytes);
e8bc2b5c 1890 }
d0bbed78
IZ
1891 FILL_DEADBEEF((unsigned char*)(ovp+CHUNK_SHIFT),
1892 BUCKET_SIZE_REAL(OV_INDEX(ovp)) + RMAGIC_SZ);
72aaf631 1893 ovp->ov_rmagic = RMAGIC - 1;
8d063cd8 1894#endif
3541dd58 1895 ASSERT(OV_INDEX(ovp) < NBUCKETS, "chunk's head overwrite");
72aaf631 1896 size = OV_INDEX(ovp);
4ad56ec9
IZ
1897
1898 MALLOC_LOCK;
72aaf631
MB
1899 ovp->ov_next = nextf[size];
1900 nextf[size] = ovp;
741df71a 1901 MALLOC_UNLOCK;
8d063cd8
LW
1902}
1903
4ad56ec9
IZ
1904/* There is no need to do any locking in realloc (with an exception of
1905 trying to grow in place if we are at the end of the chain).
1906 If somebody calls us from a different thread with the same address,
1907 we are sole anyway. */
8d063cd8 1908
2304df62 1909Malloc_t
86058a2d 1910Perl_realloc(void *mp, size_t nbytes)
cea2e8a9 1911{
899be101 1912 dVAR;
eb578fdb 1913 MEM_SIZE onb;
72aaf631 1914 union overhead *ovp;
d720c441
IZ
1915 char *res;
1916 int prev_bucket;
eb578fdb 1917 int bucket;
4ad56ec9
IZ
1918 int incr; /* 1 if does not fit, -1 if "easily" fits in a
1919 smaller bucket, otherwise 0. */
352d5a3a 1920 char *cp = (char*)mp;
8d063cd8 1921
b9e5552c 1922#ifdef DEBUGGING
ee0007ab 1923 MEM_SIZE size = nbytes;
45d8adaa 1924
45d8adaa 1925 if ((long)nbytes < 0)
cea2e8a9 1926 croak("%s", "panic: realloc");
45d8adaa 1927#endif
e8bc2b5c
GS
1928
1929 BARK_64K_LIMIT("Reallocation",nbytes,size);
1930 if (!cp)
86058a2d 1931 return Perl_malloc(nbytes);
45d8adaa 1932
72aaf631 1933 ovp = (union overhead *)((caddr_t)cp
e8bc2b5c
GS
1934 - sizeof (union overhead) * CHUNK_SHIFT);
1935 bucket = OV_INDEX(ovp);
4ad56ec9 1936
e8bc2b5c 1937#ifdef IGNORE_SMALL_BAD_FREE
4ad56ec9
IZ
1938 if ((bucket >= FIRST_BUCKET_WITH_CHECK)
1939 && (OV_MAGIC(ovp, bucket) != MAGIC))
e8bc2b5c 1940#else
4ad56ec9 1941 if (OV_MAGIC(ovp, bucket) != MAGIC)
e8bc2b5c 1942#endif
4ad56ec9
IZ
1943 {
1944 static int bad_free_warn = -1;
1945 if (bad_free_warn == -1) {
e8cd8248 1946 dTHX;
4ad56ec9
IZ
1947 char *pbf = PerlEnv_getenv("PERL_BADFREE");
1948 bad_free_warn = (pbf) ? atoi(pbf) : 1;
1949 }
1950 if (!bad_free_warn)
bd61b366 1951 return NULL;
4ad56ec9 1952#ifdef RCHECK
e8cd8248
GS
1953 {
1954 dTHX;
9b387841
NC
1955 if (!PERL_IS_ALIVE || !PL_curcop)
1956 Perl_ck_warner_d(aTHX_ packWARN(WARN_MALLOC), "%srealloc() %signored",
1957 (ovp->ov_rmagic == RMAGIC - 1 ? "" : "Bad "),
1958 ovp->ov_rmagic == RMAGIC - 1
1959 ? "of freed memory " : "");
2ba999ec 1960 }
e476b1b5 1961#else
2ba999ec
GS
1962 {
1963 dTHX;
9b387841
NC
1964 if (!PERL_IS_ALIVE || !PL_curcop)
1965 Perl_ck_warner_d(aTHX_ packWARN(WARN_MALLOC), "%s",
1966 "Bad realloc() ignored");
2ba999ec 1967 }
e476b1b5 1968#endif
bd61b366 1969 return NULL; /* sanity */
4ad56ec9
IZ
1970 }
1971
e8bc2b5c 1972 onb = BUCKET_SIZE_REAL(bucket);
55497cff 1973 /*
1974 * avoid the copy if same size block.
486ec47a 1975 * We are not aggressive with boundary cases. Note that it might
e8bc2b5c 1976 * (for a small number of cases) give false negative if
55497cff 1977 * both new size and old one are in the bucket for
e8bc2b5c
GS
1978 * FIRST_BIG_POW2, but the new one is near the lower end.
1979 *
1980 * We do not try to go to 1.5 times smaller bucket so far.
55497cff 1981 */
e8bc2b5c
GS
1982 if (nbytes > onb) incr = 1;
1983 else {
1984#ifdef DO_NOT_TRY_HARDER_WHEN_SHRINKING
1985 if ( /* This is a little bit pessimal if PACK_MALLOC: */
1986 nbytes > ( (onb >> 1) - M_OVERHEAD )
1987# ifdef TWO_POT_OPTIMIZE
1988 || (bucket == FIRST_BIG_POW2 && nbytes >= LAST_SMALL_BOUND )
1989# endif
1990 )
1991#else /* !DO_NOT_TRY_HARDER_WHEN_SHRINKING */
1992 prev_bucket = ( (bucket > MAX_PACKED + 1)
1993 ? bucket - BUCKETS_PER_POW2
1994 : bucket - 1);
1995 if (nbytes > BUCKET_SIZE_REAL(prev_bucket))
1996#endif /* !DO_NOT_TRY_HARDER_WHEN_SHRINKING */
1997 incr = 0;
1998 else incr = -1;
1999 }
2ce36478 2000#ifdef STRESS_REALLOC
4ad56ec9 2001 goto hard_way;
2ce36478 2002#endif
4ad56ec9 2003 if (incr == 0) {
852c2e52 2004 inplace_label:
a687059c
LW
2005#ifdef RCHECK
2006 /*
2007 * Record new allocated size of block and
2008 * bound space with magic numbers.
2009 */
72aaf631 2010 if (OV_INDEX(ovp) <= MAX_SHORT_BUCKET) {
e8bc2b5c
GS
2011 int i, nb = ovp->ov_size + 1;
2012
d0bbed78
IZ
2013 if ((i = nb & (RMAGIC_SZ-1))) {
2014 i = RMAGIC_SZ - i;
2015 while (i--) { /* nb - RMAGIC_SZ is end of alloced area */
2016 ASSERT(((caddr_t)ovp + nb - RMAGIC_SZ)[i] == RMAGIC_C, "chunk's tail overwrite");
e8bc2b5c
GS
2017 }
2018 }
d0bbed78
IZ
2019 /* Same at RMAGIC_SZ-aligned RMAGIC */
2020 nb = (nb + (RMAGIC_SZ-1)) & ~(RMAGIC_SZ-1);
2021 ASSERT(((u_int *)((caddr_t)ovp + nb))[-1] == RMAGIC,
2022 "chunk's tail overwrite");
2023 FILLCHECK_DEADBEEF((unsigned char*)((caddr_t)ovp + nb),
2024 BUCKET_SIZE(OV_INDEX(ovp)) - nb);
22f7c9c9
JH
2025 if (nbytes > ovp->ov_size + 1 - M_OVERHEAD)
2026 FILL_FEEDADAD((unsigned char*)cp + ovp->ov_size + 1 - M_OVERHEAD,
2027 nbytes - (ovp->ov_size + 1 - M_OVERHEAD));
2028 else
2029 FILL_DEADBEEF((unsigned char*)cp + nbytes,
d0bbed78 2030 nb - M_OVERHEAD + RMAGIC_SZ - nbytes);
a687059c
LW
2031 /*
2032 * Convert amount of memory requested into
2033 * closest block size stored in hash buckets
2034 * which satisfies request. Account for
2035 * space used per block for accounting.
2036 */
cf5c4ad8 2037 nbytes += M_OVERHEAD;
72aaf631 2038 ovp->ov_size = nbytes - 1;
d0bbed78
IZ
2039 if ((i = nbytes & (RMAGIC_SZ-1))) {
2040 i = RMAGIC_SZ - i;
2041 while (i--) /* nbytes - RMAGIC_SZ is end of alloced area */
2042 ((caddr_t)ovp + nbytes - RMAGIC_SZ)[i]
e8bc2b5c
GS
2043 = RMAGIC_C;
2044 }
d0bbed78
IZ
2045 /* Same at RMAGIC_SZ-aligned RMAGIC */
2046 nbytes = (nbytes + (RMAGIC_SZ-1)) & ~(RMAGIC_SZ - 1);
2047 ((u_int *)((caddr_t)ovp + nbytes))[-1] = RMAGIC;
a687059c
LW
2048 }
2049#endif
45d8adaa 2050 res = cp;
42ac124e 2051 DEBUG_m(PerlIO_printf(Perl_debug_log,
b900a521
JH
2052 "0x%"UVxf": (%05lu) realloc %ld bytes inplace\n",
2053 PTR2UV(res),(unsigned long)(PL_an++),
42ac124e 2054 (long)size));
e8bc2b5c
GS
2055 } else if (incr == 1 && (cp - M_OVERHEAD == last_op)
2056 && (onb > (1 << LOG_OF_MIN_ARENA))) {
2057 MEM_SIZE require, newarena = nbytes, pow;
2058 int shiftr;
2059
2060 POW2_OPTIMIZE_ADJUST(newarena);
2061 newarena = newarena + M_OVERHEAD;
2062 /* newarena = (newarena + 3) &~ 3; */
2063 shiftr = (newarena - 1) >> LOG_OF_MIN_ARENA;
2064 pow = LOG_OF_MIN_ARENA + 1;
2065 /* apart from this loop, this is O(1) */
2066 while (shiftr >>= 1)
2067 pow++;
2068 newarena = (1 << pow) + POW2_OPTIMIZE_SURPLUS(pow * BUCKETS_PER_POW2);
2069 require = newarena - onb - M_OVERHEAD;
2070
4ad56ec9
IZ
2071 MALLOC_LOCK;
2072 if (cp - M_OVERHEAD == last_op /* We *still* are the last chunk */
2073 && getpages_adjacent(require)) {
e8bc2b5c 2074#ifdef DEBUGGING_MSTATS
fa423c5b
IZ
2075 nmalloc[bucket]--;
2076 nmalloc[pow * BUCKETS_PER_POW2]++;
e8bc2b5c 2077#endif
532939df 2078 if (pow * BUCKETS_PER_POW2 > (MEM_SIZE)max_bucket)
a73918ec 2079 max_bucket = pow * BUCKETS_PER_POW2;
4d6cd4d8 2080 *(cp - M_OVERHEAD) = pow * BUCKETS_PER_POW2; /* Fill index. */
4ad56ec9 2081 MALLOC_UNLOCK;
fa423c5b 2082 goto inplace_label;
4ad56ec9
IZ
2083 } else {
2084 MALLOC_UNLOCK;
fa423c5b 2085 goto hard_way;
4ad56ec9 2086 }
e8bc2b5c
GS
2087 } else {
2088 hard_way:
42ac124e 2089 DEBUG_m(PerlIO_printf(Perl_debug_log,
b900a521
JH
2090 "0x%"UVxf": (%05lu) realloc %ld bytes the hard way\n",
2091 PTR2UV(cp),(unsigned long)(PL_an++),
42ac124e 2092 (long)size));
86058a2d 2093 if ((res = (char*)Perl_malloc(nbytes)) == NULL)
e8bc2b5c
GS
2094 return (NULL);
2095 if (cp != res) /* common optimization */
2096 Copy(cp, res, (MEM_SIZE)(nbytes<onb?nbytes:onb), char);
4ad56ec9 2097 Perl_mfree(cp);
45d8adaa 2098 }
2304df62 2099 return ((Malloc_t)res);
8d063cd8
LW
2100}
2101
cf5c4ad8 2102Malloc_t
5aaab254 2103Perl_calloc(size_t elements, size_t size)
cf5c4ad8 2104{
2105 long sz = elements * size;
86058a2d 2106 Malloc_t p = Perl_malloc(sz);
cf5c4ad8 2107
2108 if (p) {
2109 memset((void*)p, 0, sz);
2110 }
2111 return p;
2112}
2113
4ad56ec9
IZ
2114char *
2115Perl_strdup(const char *s)
2116{
2117 MEM_SIZE l = strlen(s);
b48f1ba5 2118 char *s1 = (char *)Perl_malloc(l+1);
4ad56ec9 2119
667e2948 2120 return (char *)CopyD(s, s1, (MEM_SIZE)(l+1), char);
4ad56ec9
IZ
2121}
2122
4ad56ec9
IZ
2123int
2124Perl_putenv(char *a)
2125{
2126 /* Sometimes system's putenv conflicts with my_setenv() - this is system
2127 malloc vs Perl's free(). */
2128 dTHX;
2129 char *var;
2130 char *val = a;
2131 MEM_SIZE l;
2132 char buf[80];
2133
2134 while (*val && *val != '=')
2135 val++;
2136 if (!*val)
2137 return -1;
2138 l = val - a;
2139 if (l < sizeof(buf))
2140 var = buf;
2141 else
667e2948 2142 var = (char *)Perl_malloc(l + 1);
4ad56ec9 2143 Copy(a, var, l, char);
b48f1ba5
GS
2144 var[l + 1] = 0;
2145 my_setenv(var, val+1);
4ad56ec9
IZ
2146 if (var != buf)
2147 Perl_mfree(var);
2148 return 0;
2149}
4ad56ec9 2150
e8bc2b5c 2151MEM_SIZE
cea2e8a9 2152Perl_malloced_size(void *p)
e8bc2b5c 2153{
44f8325f 2154 union overhead * const ovp = (union overhead *)
8d6dde3e 2155 ((caddr_t)p - sizeof (union overhead) * CHUNK_SHIFT);
b464bac0 2156 const int bucket = OV_INDEX(ovp);
7918f24d
NC
2157
2158 PERL_ARGS_ASSERT_MALLOCED_SIZE;
2159
8d6dde3e
IZ
2160#ifdef RCHECK
2161 /* The caller wants to have a complete control over the chunk,
2162 disable the memory checking inside the chunk. */
2163 if (bucket <= MAX_SHORT_BUCKET) {
b464bac0 2164 const MEM_SIZE size = BUCKET_SIZE_REAL(bucket);
8d6dde3e 2165 ovp->ov_size = size + M_OVERHEAD - 1;
d0bbed78 2166 *((u_int *)((caddr_t)ovp + size + M_OVERHEAD - RMAGIC_SZ)) = RMAGIC;
8d6dde3e
IZ
2167 }
2168#endif
e8bc2b5c
GS
2169 return BUCKET_SIZE_REAL(bucket);
2170}
2171
64107180
NC
2172
2173MEM_SIZE
2174Perl_malloc_good_size(size_t wanted)
2175{
0eccc83d 2176 return BUCKET_SIZE_REAL(S_adjust_size_and_find_bucket(&wanted));
64107180
NC
2177}
2178
e8bc2b5c
GS
2179# ifdef BUCKETS_ROOT2
2180# define MIN_EVEN_REPORT 6
2181# else
2182# define MIN_EVEN_REPORT MIN_BUCKET
2183# endif
827e134a
GS
2184
2185int
2186Perl_get_mstats(pTHX_ perl_mstats_t *buf, int buflen, int level)
8d063cd8 2187{
df31f264 2188#ifdef DEBUGGING_MSTATS
eb578fdb
KW
2189 int i, j;
2190 union overhead *p;
4ad56ec9 2191 struct chunk_chain_s* nextchain;
8d063cd8 2192
7918f24d
NC
2193 PERL_ARGS_ASSERT_GET_MSTATS;
2194
827e134a
GS
2195 buf->topbucket = buf->topbucket_ev = buf->topbucket_odd
2196 = buf->totfree = buf->total = buf->total_chain = 0;
2197
2198 buf->minbucket = MIN_BUCKET;
4ad56ec9 2199 MALLOC_LOCK;
e8bc2b5c 2200 for (i = MIN_BUCKET ; i < NBUCKETS; i++) {
8d063cd8
LW
2201 for (j = 0, p = nextf[i]; p; p = p->ov_next, j++)
2202 ;
827e134a
GS
2203 if (i < buflen) {
2204 buf->nfree[i] = j;
2205 buf->ntotal[i] = nmalloc[i];
2206 }
2207 buf->totfree += j * BUCKET_SIZE_REAL(i);
2208 buf->total += nmalloc[i] * BUCKET_SIZE_REAL(i);
e8bc2b5c 2209 if (nmalloc[i]) {
827e134a
GS
2210 i % 2 ? (buf->topbucket_odd = i) : (buf->topbucket_ev = i);
2211 buf->topbucket = i;
e8bc2b5c 2212 }
c07a80fd 2213 }
4ad56ec9
IZ
2214 nextchain = chunk_chain;
2215 while (nextchain) {
827e134a 2216 buf->total_chain += nextchain->size;
4ad56ec9
IZ
2217 nextchain = nextchain->next;
2218 }
827e134a
GS
2219 buf->total_sbrk = goodsbrk + sbrk_slack;
2220 buf->sbrks = sbrks;
22f7c9c9 2221 buf->sbrk_good = sbrk_goodness;
827e134a
GS
2222 buf->sbrk_slack = sbrk_slack;
2223 buf->start_slack = start_slack;
2224 buf->sbrked_remains = sbrked_remains;
4ad56ec9 2225 MALLOC_UNLOCK;
880b20b6 2226 buf->nbuckets = NBUCKETS;
827e134a
GS
2227 if (level) {
2228 for (i = MIN_BUCKET ; i < NBUCKETS; i++) {
2229 if (i >= buflen)
2230 break;
d0bbed78 2231 buf->bucket_mem_size[i] = BUCKET_SIZE_NO_SURPLUS(i);
827e134a
GS
2232 buf->bucket_available_size[i] = BUCKET_SIZE_REAL(i);
2233 }
2234 }
3128eefe
SR
2235#else /* defined DEBUGGING_MSTATS */
2236 PerlIO_printf(Perl_error_log, "perl not compiled with DEBUGGING_MSTATS\n");
827e134a 2237#endif /* defined DEBUGGING_MSTATS */
fe52b3b7 2238 return 0; /* XXX unused */
827e134a
GS
2239}
2240/*
2241 * mstats - print out statistics about malloc
2242 *
2243 * Prints two lines of numbers, one showing the length of the free list
2244 * for each size category, the second showing the number of mallocs -
2245 * frees for each size category.
2246 */
2247void
6e9b0e18 2248Perl_dump_mstats(pTHX_ const char *s)
827e134a
GS
2249{
2250#ifdef DEBUGGING_MSTATS
eb578fdb 2251 int i;
827e134a 2252 perl_mstats_t buffer;
880b20b6
IZ
2253 UV nf[NBUCKETS];
2254 UV nt[NBUCKETS];
827e134a 2255
7918f24d
NC
2256 PERL_ARGS_ASSERT_DUMP_MSTATS;
2257
827e134a
GS
2258 buffer.nfree = nf;
2259 buffer.ntotal = nt;
2260 get_mstats(&buffer, NBUCKETS, 0);
2261
c07a80fd 2262 if (s)
bf49b057 2263 PerlIO_printf(Perl_error_log,
880b20b6 2264 "Memory allocation statistics %s (buckets %"IVdf"(%"IVdf")..%"IVdf"(%"IVdf")\n",
e8bc2b5c 2265 s,
880b20b6 2266 (IV)BUCKET_SIZE_REAL(MIN_BUCKET),
d0bbed78 2267 (IV)BUCKET_SIZE_NO_SURPLUS(MIN_BUCKET),
880b20b6 2268 (IV)BUCKET_SIZE_REAL(buffer.topbucket),
d0bbed78 2269 (IV)BUCKET_SIZE_NO_SURPLUS(buffer.topbucket));
880b20b6 2270 PerlIO_printf(Perl_error_log, "%8"IVdf" free:", buffer.totfree);
827e134a 2271 for (i = MIN_EVEN_REPORT; i <= buffer.topbucket; i += BUCKETS_PER_POW2) {
bf49b057 2272 PerlIO_printf(Perl_error_log,
e8bc2b5c 2273 ((i < 8*BUCKETS_PER_POW2 || i == 10*BUCKETS_PER_POW2)
880b20b6
IZ
2274 ? " %5"UVuf
2275 : ((i < 12*BUCKETS_PER_POW2) ? " %3"UVuf : " %"UVuf)),
827e134a 2276 buffer.nfree[i]);
e8bc2b5c
GS
2277 }
2278#ifdef BUCKETS_ROOT2
bf49b057 2279 PerlIO_printf(Perl_error_log, "\n\t ");
827e134a 2280 for (i = MIN_BUCKET + 1; i <= buffer.topbucket_odd; i += BUCKETS_PER_POW2) {
bf49b057 2281 PerlIO_printf(Perl_error_log,
e8bc2b5c 2282 ((i < 8*BUCKETS_PER_POW2 || i == 10*BUCKETS_PER_POW2)
880b20b6
IZ
2283 ? " %5"UVuf
2284 : ((i < 12*BUCKETS_PER_POW2) ? " %3"UVuf : " %"UVuf)),
827e134a 2285 buffer.nfree[i]);
8d063cd8 2286 }
e8bc2b5c 2287#endif
880b20b6 2288 PerlIO_printf(Perl_error_log, "\n%8"IVdf" used:", buffer.total - buffer.totfree);
827e134a 2289 for (i = MIN_EVEN_REPORT; i <= buffer.topbucket; i += BUCKETS_PER_POW2) {
bf49b057 2290 PerlIO_printf(Perl_error_log,
e8bc2b5c 2291 ((i < 8*BUCKETS_PER_POW2 || i == 10*BUCKETS_PER_POW2)
880b20b6
IZ
2292 ? " %5"IVdf
2293 : ((i < 12*BUCKETS_PER_POW2) ? " %3"IVdf : " %"IVdf)),
827e134a 2294 buffer.ntotal[i] - buffer.nfree[i]);
c07a80fd 2295 }
e8bc2b5c 2296#ifdef BUCKETS_ROOT2
bf49b057 2297 PerlIO_printf(Perl_error_log, "\n\t ");
827e134a 2298 for (i = MIN_BUCKET + 1; i <= buffer.topbucket_odd; i += BUCKETS_PER_POW2) {
bf49b057 2299 PerlIO_printf(Perl_error_log,
e8bc2b5c 2300 ((i < 8*BUCKETS_PER_POW2 || i == 10*BUCKETS_PER_POW2)
880b20b6
IZ
2301 ? " %5"IVdf
2302 : ((i < 12*BUCKETS_PER_POW2) ? " %3"IVdf : " %"IVdf)),
827e134a 2303 buffer.ntotal[i] - buffer.nfree[i]);
e8bc2b5c
GS
2304 }
2305#endif
880b20b6 2306 PerlIO_printf(Perl_error_log, "\nTotal sbrk(): %"IVdf"/%"IVdf":%"IVdf". Odd ends: pad+heads+chain+tail: %"IVdf"+%"IVdf"+%"IVdf"+%"IVdf".\n",
827e134a
GS
2307 buffer.total_sbrk, buffer.sbrks, buffer.sbrk_good,
2308 buffer.sbrk_slack, buffer.start_slack,
2309 buffer.total_chain, buffer.sbrked_remains);
3128eefe
SR
2310#else /* DEBUGGING_MSTATS */
2311 PerlIO_printf(Perl_error_log, "%s: perl not compiled with DEBUGGING_MSTATS\n",s);
df31f264 2312#endif /* DEBUGGING_MSTATS */
c07a80fd 2313}
cf5c4ad8 2314
cf5c4ad8 2315#ifdef USE_PERL_SBRK
2316
e94c1c05 2317# if defined(NeXT) || defined(__NeXT__) || defined(PURIFY)
38ac2dc8 2318# define PERL_SBRK_VIA_MALLOC
38ac2dc8
DD
2319# endif
2320
760ac839 2321# ifdef PERL_SBRK_VIA_MALLOC
cf5c4ad8 2322
2323/* it may seem schizophrenic to use perl's malloc and let it call system */
2324/* malloc, the reason for that is only the 3.2 version of the OS that had */
2325/* frequent core dumps within nxzonefreenolock. This sbrk routine put an */
2326/* end to the cores */
2327
38ac2dc8
DD
2328# ifndef SYSTEM_ALLOC
2329# define SYSTEM_ALLOC(a) malloc(a)
2330# endif
5bbd1ef5
IZ
2331# ifndef SYSTEM_ALLOC_ALIGNMENT
2332# define SYSTEM_ALLOC_ALIGNMENT MEM_ALIGNBYTES
2333# endif
cf5c4ad8 2334
760ac839 2335# endif /* PERL_SBRK_VIA_MALLOC */
cf5c4ad8 2336
2337static IV Perl_sbrk_oldchunk;
2338static long Perl_sbrk_oldsize;
2339
760ac839
LW
2340# define PERLSBRK_32_K (1<<15)
2341# define PERLSBRK_64_K (1<<16)
cf5c4ad8 2342
b63effbb 2343Malloc_t
df0003d4 2344Perl_sbrk(int size)
cf5c4ad8 2345{
2346 IV got;
2347 int small, reqsize;
2348
2349 if (!size) return 0;
cf5c4ad8 2350 reqsize = size; /* just for the DEBUG_m statement */
57569e04
HM
2351#ifdef PACK_MALLOC
2352 size = (size + 0x7ff) & ~0x7ff;
2353#endif
cf5c4ad8 2354 if (size <= Perl_sbrk_oldsize) {
2355 got = Perl_sbrk_oldchunk;
2356 Perl_sbrk_oldchunk += size;
2357 Perl_sbrk_oldsize -= size;
2358 } else {
2359 if (size >= PERLSBRK_32_K) {
2360 small = 0;
2361 } else {
cf5c4ad8 2362 size = PERLSBRK_64_K;
2363 small = 1;
2364 }
5bbd1ef5
IZ
2365# if NEEDED_ALIGNMENT > SYSTEM_ALLOC_ALIGNMENT
2366 size += NEEDED_ALIGNMENT - SYSTEM_ALLOC_ALIGNMENT;
2367# endif
cf5c4ad8 2368 got = (IV)SYSTEM_ALLOC(size);
5bbd1ef5 2369# if NEEDED_ALIGNMENT > SYSTEM_ALLOC_ALIGNMENT
5a7d6335 2370 got = (got + NEEDED_ALIGNMENT - 1) & ~(NEEDED_ALIGNMENT - 1);
5bbd1ef5 2371# endif
cf5c4ad8 2372 if (small) {
2373 /* Chunk is small, register the rest for future allocs. */
2374 Perl_sbrk_oldchunk = got + reqsize;
2375 Perl_sbrk_oldsize = size - reqsize;
2376 }
2377 }
2378
b900a521
JH
2379 DEBUG_m(PerlIO_printf(Perl_debug_log, "sbrk malloc size %ld (reqsize %ld), left size %ld, give addr 0x%"UVxf"\n",
2380 size, reqsize, Perl_sbrk_oldsize, PTR2UV(got)));
cf5c4ad8 2381
2382 return (void *)got;
2383}
2384
2385#endif /* ! defined USE_PERL_SBRK */
66610fdd
RGS
2386
2387/*
2388 * Local variables:
2389 * c-indentation-style: bsd
2390 * c-basic-offset: 4
14d04a33 2391 * indent-tabs-mode: nil
66610fdd
RGS
2392 * End:
2393 *
14d04a33 2394 * ex: set ts=8 sts=4 sw=4 et:
37442d52 2395 */