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give REGEXP SVs the POK flag again
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5356d32e 1/* sv.c
79072805 2 *
1129b882 3 * Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
83706693
RGS
4 * 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 by Larry Wall
5 * and others
79072805
LW
6 *
7 * You may distribute under the terms of either the GNU General Public
8 * License or the Artistic License, as specified in the README file.
9 *
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TC
10 */
11
12/*
13 * 'I wonder what the Entish is for "yes" and "no",' he thought.
14 * --Pippin
15 *
16 * [p.480 of _The Lord of the Rings_, III/iv: "Treebeard"]
17 */
18
19/*
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20 *
21 *
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AMS
22 * This file contains the code that creates, manipulates and destroys
23 * scalar values (SVs). The other types (AV, HV, GV, etc.) reuse the
24 * structure of an SV, so their creation and destruction is handled
25 * here; higher-level functions are in av.c, hv.c, and so on. Opcode
26 * level functions (eg. substr, split, join) for each of the types are
27 * in the pp*.c files.
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LW
28 */
29
30#include "EXTERN.h"
864dbfa3 31#define PERL_IN_SV_C
79072805 32#include "perl.h"
d2f185dc 33#include "regcomp.h"
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34#ifdef __VMS
35# include <rms.h>
36#endif
79072805 37
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38#ifdef __Lynx__
39/* Missing proto on LynxOS */
40 char *gconvert(double, int, int, char *);
41#endif
42
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43#ifdef USE_QUADMATH
44# define SNPRINTF_G(nv, buffer, size, ndig) \
45 quadmath_snprintf(buffer, size, "%.*Qg", (int)ndig, (NV)(nv))
46#else
47# define SNPRINTF_G(nv, buffer, size, ndig) \
48 PERL_UNUSED_RESULT(Gconvert((NV)(nv), (int)ndig, 0, buffer))
49#endif
50
9f53080a 51#ifndef SV_COW_THRESHOLD
e8c6a474 52# define SV_COW_THRESHOLD 0 /* COW iff len > K */
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53#endif
54#ifndef SV_COWBUF_THRESHOLD
e8c6a474 55# define SV_COWBUF_THRESHOLD 1250 /* COW iff len > K */
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56#endif
57#ifndef SV_COW_MAX_WASTE_THRESHOLD
e8c6a474 58# define SV_COW_MAX_WASTE_THRESHOLD 80 /* COW iff (len - cur) < K */
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59#endif
60#ifndef SV_COWBUF_WASTE_THRESHOLD
e8c6a474 61# define SV_COWBUF_WASTE_THRESHOLD 80 /* COW iff (len - cur) < K */
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62#endif
63#ifndef SV_COW_MAX_WASTE_FACTOR_THRESHOLD
e8c6a474 64# define SV_COW_MAX_WASTE_FACTOR_THRESHOLD 2 /* COW iff len < (cur * K) */
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65#endif
66#ifndef SV_COWBUF_WASTE_FACTOR_THRESHOLD
e8c6a474 67# define SV_COWBUF_WASTE_FACTOR_THRESHOLD 2 /* COW iff len < (cur * K) */
e8c6a474
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68#endif
69/* Work around compiler warnings about unsigned >= THRESHOLD when thres-
70 hold is 0. */
71#if SV_COW_THRESHOLD
72# define GE_COW_THRESHOLD(cur) ((cur) >= SV_COW_THRESHOLD)
73#else
74# define GE_COW_THRESHOLD(cur) 1
75#endif
76#if SV_COWBUF_THRESHOLD
77# define GE_COWBUF_THRESHOLD(cur) ((cur) >= SV_COWBUF_THRESHOLD)
78#else
79# define GE_COWBUF_THRESHOLD(cur) 1
80#endif
81#if SV_COW_MAX_WASTE_THRESHOLD
82# define GE_COW_MAX_WASTE_THRESHOLD(cur,len) (((len)-(cur)) < SV_COW_MAX_WASTE_THRESHOLD)
83#else
84# define GE_COW_MAX_WASTE_THRESHOLD(cur,len) 1
85#endif
86#if SV_COWBUF_WASTE_THRESHOLD
87# define GE_COWBUF_WASTE_THRESHOLD(cur,len) (((len)-(cur)) < SV_COWBUF_WASTE_THRESHOLD)
88#else
89# define GE_COWBUF_WASTE_THRESHOLD(cur,len) 1
90#endif
91#if SV_COW_MAX_WASTE_FACTOR_THRESHOLD
92# define GE_COW_MAX_WASTE_FACTOR_THRESHOLD(cur,len) ((len) < SV_COW_MAX_WASTE_FACTOR_THRESHOLD * (cur))
93#else
94# define GE_COW_MAX_WASTE_FACTOR_THRESHOLD(cur,len) 1
95#endif
96#if SV_COWBUF_WASTE_FACTOR_THRESHOLD
97# define GE_COWBUF_WASTE_FACTOR_THRESHOLD(cur,len) ((len) < SV_COWBUF_WASTE_FACTOR_THRESHOLD * (cur))
98#else
99# define GE_COWBUF_WASTE_FACTOR_THRESHOLD(cur,len) 1
100#endif
101
102#define CHECK_COW_THRESHOLD(cur,len) (\
103 GE_COW_THRESHOLD((cur)) && \
104 GE_COW_MAX_WASTE_THRESHOLD((cur),(len)) && \
105 GE_COW_MAX_WASTE_FACTOR_THRESHOLD((cur),(len)) \
106)
107#define CHECK_COWBUF_THRESHOLD(cur,len) (\
108 GE_COWBUF_THRESHOLD((cur)) && \
109 GE_COWBUF_WASTE_THRESHOLD((cur),(len)) && \
110 GE_COWBUF_WASTE_FACTOR_THRESHOLD((cur),(len)) \
111)
cca0492e 112
e23c8137 113#ifdef PERL_UTF8_CACHE_ASSERT
ab455f60 114/* if adding more checks watch out for the following tests:
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115 * t/op/index.t t/op/length.t t/op/pat.t t/op/substr.t
116 * lib/utf8.t lib/Unicode/Collate/t/index.t
117 * --jhi
118 */
6f207bd3 119# define ASSERT_UTF8_CACHE(cache) \
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120 STMT_START { if (cache) { assert((cache)[0] <= (cache)[1]); \
121 assert((cache)[2] <= (cache)[3]); \
122 assert((cache)[3] <= (cache)[1]);} \
123 } STMT_END
e23c8137 124#else
6f207bd3 125# define ASSERT_UTF8_CACHE(cache) NOOP
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126#endif
127
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128static const char S_destroy[] = "DESTROY";
129#define S_destroy_len (sizeof(S_destroy)-1)
130
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131/* ============================================================================
132
133=head1 Allocation and deallocation of SVs.
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134An SV (or AV, HV, etc.) is allocated in two parts: the head (struct
135sv, av, hv...) contains type and reference count information, and for
136many types, a pointer to the body (struct xrv, xpv, xpviv...), which
137contains fields specific to each type. Some types store all they need
138in the head, so don't have a body.
139
486ec47a 140In all but the most memory-paranoid configurations (ex: PURIFY), heads
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141and bodies are allocated out of arenas, which by default are
142approximately 4K chunks of memory parcelled up into N heads or bodies.
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143Sv-bodies are allocated by their sv-type, guaranteeing size
144consistency needed to allocate safely from arrays.
145
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146For SV-heads, the first slot in each arena is reserved, and holds a
147link to the next arena, some flags, and a note of the number of slots.
148Snaked through each arena chain is a linked list of free items; when
149this becomes empty, an extra arena is allocated and divided up into N
150items which are threaded into the free list.
151
152SV-bodies are similar, but they use arena-sets by default, which
153separate the link and info from the arena itself, and reclaim the 1st
154slot in the arena. SV-bodies are further described later.
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155
156The following global variables are associated with arenas:
157
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158 PL_sv_arenaroot pointer to list of SV arenas
159 PL_sv_root pointer to list of free SV structures
645c22ef 160
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161 PL_body_arenas head of linked-list of body arenas
162 PL_body_roots[] array of pointers to list of free bodies of svtype
163 arrays are indexed by the svtype needed
93e68bfb 164
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165A few special SV heads are not allocated from an arena, but are
166instead directly created in the interpreter structure, eg PL_sv_undef.
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167The size of arenas can be changed from the default by setting
168PERL_ARENA_SIZE appropriately at compile time.
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169
170The SV arena serves the secondary purpose of allowing still-live SVs
171to be located and destroyed during final cleanup.
172
173At the lowest level, the macros new_SV() and del_SV() grab and free
174an SV head. (If debugging with -DD, del_SV() calls the function S_del_sv()
175to return the SV to the free list with error checking.) new_SV() calls
176more_sv() / sv_add_arena() to add an extra arena if the free list is empty.
177SVs in the free list have their SvTYPE field set to all ones.
178
ff276b08 179At the time of very final cleanup, sv_free_arenas() is called from
645c22ef 180perl_destruct() to physically free all the arenas allocated since the
6a93a7e5 181start of the interpreter.
645c22ef 182
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183The function visit() scans the SV arenas list, and calls a specified
184function for each SV it finds which is still live - ie which has an SvTYPE
185other than all 1's, and a non-zero SvREFCNT. visit() is used by the
186following functions (specified as [function that calls visit()] / [function
187called by visit() for each SV]):
188
189 sv_report_used() / do_report_used()
f2524eef 190 dump all remaining SVs (debugging aid)
645c22ef 191
e4487e9b 192 sv_clean_objs() / do_clean_objs(),do_clean_named_objs(),
e76981f9 193 do_clean_named_io_objs(),do_curse()
645c22ef 194 Attempt to free all objects pointed to by RVs,
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195 try to do the same for all objects indir-
196 ectly referenced by typeglobs too, and
197 then do a final sweep, cursing any
198 objects that remain. Called once from
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199 perl_destruct(), prior to calling sv_clean_all()
200 below.
201
202 sv_clean_all() / do_clean_all()
203 SvREFCNT_dec(sv) each remaining SV, possibly
204 triggering an sv_free(). It also sets the
205 SVf_BREAK flag on the SV to indicate that the
206 refcnt has been artificially lowered, and thus
207 stopping sv_free() from giving spurious warnings
208 about SVs which unexpectedly have a refcnt
209 of zero. called repeatedly from perl_destruct()
210 until there are no SVs left.
211
93e68bfb 212=head2 Arena allocator API Summary
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213
214Private API to rest of sv.c
215
216 new_SV(), del_SV(),
217
df0f0429 218 new_XPVNV(), del_XPVGV(),
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219 etc
220
221Public API:
222
8cf8f3d1 223 sv_report_used(), sv_clean_objs(), sv_clean_all(), sv_free_arenas()
645c22ef 224
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225=cut
226
3e8320cc 227 * ========================================================================= */
645c22ef 228
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229/*
230 * "A time to plant, and a time to uproot what was planted..."
231 */
232
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233#ifdef PERL_MEM_LOG
234# define MEM_LOG_NEW_SV(sv, file, line, func) \
235 Perl_mem_log_new_sv(sv, file, line, func)
236# define MEM_LOG_DEL_SV(sv, file, line, func) \
237 Perl_mem_log_del_sv(sv, file, line, func)
238#else
239# define MEM_LOG_NEW_SV(sv, file, line, func) NOOP
240# define MEM_LOG_DEL_SV(sv, file, line, func) NOOP
241#endif
242
fd0854ff 243#ifdef DEBUG_LEAKING_SCALARS
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FC
244# define FREE_SV_DEBUG_FILE(sv) STMT_START { \
245 if ((sv)->sv_debug_file) PerlMemShared_free((sv)->sv_debug_file); \
246 } STMT_END
d7a2c63c 247# define DEBUG_SV_SERIAL(sv) \
147e3846 248 DEBUG_m(PerlIO_printf(Perl_debug_log, "0x%" UVxf ": (%05ld) del_SV\n", \
d7a2c63c 249 PTR2UV(sv), (long)(sv)->sv_debug_serial))
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250#else
251# define FREE_SV_DEBUG_FILE(sv)
d7a2c63c 252# define DEBUG_SV_SERIAL(sv) NOOP
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253#endif
254
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255#ifdef PERL_POISON
256# define SvARENA_CHAIN(sv) ((sv)->sv_u.svu_rv)
daba3364 257# define SvARENA_CHAIN_SET(sv,val) (sv)->sv_u.svu_rv = MUTABLE_SV((val))
48614a46
NC
258/* Whilst I'd love to do this, it seems that things like to check on
259 unreferenced scalars
ce5dbf61 260# define POISON_SV_HEAD(sv) PoisonNew(sv, 1, struct STRUCT_SV)
48614a46 261*/
ce5dbf61 262# define POISON_SV_HEAD(sv) PoisonNew(&SvANY(sv), 1, void *), \
7e337ee0 263 PoisonNew(&SvREFCNT(sv), 1, U32)
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NC
264#else
265# define SvARENA_CHAIN(sv) SvANY(sv)
3eef1deb 266# define SvARENA_CHAIN_SET(sv,val) SvANY(sv) = (void *)(val)
ce5dbf61 267# define POISON_SV_HEAD(sv)
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268#endif
269
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270/* Mark an SV head as unused, and add to free list.
271 *
272 * If SVf_BREAK is set, skip adding it to the free list, as this SV had
273 * its refcount artificially decremented during global destruction, so
274 * there may be dangling pointers to it. The last thing we want in that
275 * case is for it to be reused. */
276
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277#define plant_SV(p) \
278 STMT_START { \
990198f0 279 const U32 old_flags = SvFLAGS(p); \
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280 MEM_LOG_DEL_SV(p, __FILE__, __LINE__, FUNCTION__); \
281 DEBUG_SV_SERIAL(p); \
fd0854ff 282 FREE_SV_DEBUG_FILE(p); \
ce5dbf61 283 POISON_SV_HEAD(p); \
053fc874 284 SvFLAGS(p) = SVTYPEMASK; \
990198f0 285 if (!(old_flags & SVf_BREAK)) { \
3eef1deb 286 SvARENA_CHAIN_SET(p, PL_sv_root); \
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287 PL_sv_root = (p); \
288 } \
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289 --PL_sv_count; \
290 } STMT_END
a0d0e21e 291
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292#define uproot_SV(p) \
293 STMT_START { \
294 (p) = PL_sv_root; \
daba3364 295 PL_sv_root = MUTABLE_SV(SvARENA_CHAIN(p)); \
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296 ++PL_sv_count; \
297 } STMT_END
298
645c22ef 299
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300/* make some more SVs by adding another arena */
301
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302STATIC SV*
303S_more_sv(pTHX)
304{
305 SV* sv;
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306 char *chunk; /* must use New here to match call to */
307 Newx(chunk,PERL_ARENA_SIZE,char); /* Safefree() in sv_free_arenas() */
308 sv_add_arena(chunk, PERL_ARENA_SIZE, 0);
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309 uproot_SV(sv);
310 return sv;
311}
312
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313/* new_SV(): return a new, empty SV head */
314
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315#ifdef DEBUG_LEAKING_SCALARS
316/* provide a real function for a debugger to play with */
317STATIC SV*
d7a2c63c 318S_new_SV(pTHX_ const char *file, int line, const char *func)
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319{
320 SV* sv;
321
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322 if (PL_sv_root)
323 uproot_SV(sv);
324 else
cac9b346 325 sv = S_more_sv(aTHX);
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326 SvANY(sv) = 0;
327 SvREFCNT(sv) = 1;
328 SvFLAGS(sv) = 0;
fd0854ff 329 sv->sv_debug_optype = PL_op ? PL_op->op_type : 0;
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330 sv->sv_debug_line = (U16) (PL_parser && PL_parser->copline != NOLINE
331 ? PL_parser->copline
332 : PL_curcop
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DM
333 ? CopLINE(PL_curcop)
334 : 0
e385c3bf 335 );
fd0854ff 336 sv->sv_debug_inpad = 0;
cd676548 337 sv->sv_debug_parent = NULL;
484e6108 338 sv->sv_debug_file = PL_curcop ? savesharedpv(CopFILE(PL_curcop)): NULL;
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339
340 sv->sv_debug_serial = PL_sv_serial++;
341
342 MEM_LOG_NEW_SV(sv, file, line, func);
147e3846 343 DEBUG_m(PerlIO_printf(Perl_debug_log, "0x%" UVxf ": (%05ld) new_SV (from %s:%d [%s])\n",
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344 PTR2UV(sv), (long)sv->sv_debug_serial, file, line, func));
345
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346 return sv;
347}
d7a2c63c 348# define new_SV(p) (p)=S_new_SV(aTHX_ __FILE__, __LINE__, FUNCTION__)
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349
350#else
351# define new_SV(p) \
053fc874 352 STMT_START { \
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353 if (PL_sv_root) \
354 uproot_SV(p); \
355 else \
cac9b346 356 (p) = S_more_sv(aTHX); \
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357 SvANY(p) = 0; \
358 SvREFCNT(p) = 1; \
359 SvFLAGS(p) = 0; \
d7a2c63c 360 MEM_LOG_NEW_SV(p, __FILE__, __LINE__, FUNCTION__); \
053fc874 361 } STMT_END
eba0f806 362#endif
463ee0b2 363
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364
365/* del_SV(): return an empty SV head to the free list */
366
a0d0e21e 367#ifdef DEBUGGING
4561caa4 368
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369#define del_SV(p) \
370 STMT_START { \
aea4f609 371 if (DEBUG_D_TEST) \
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372 del_sv(p); \
373 else \
374 plant_SV(p); \
053fc874 375 } STMT_END
a0d0e21e 376
76e3520e 377STATIC void
cea2e8a9 378S_del_sv(pTHX_ SV *p)
463ee0b2 379{
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380 PERL_ARGS_ASSERT_DEL_SV;
381
aea4f609 382 if (DEBUG_D_TEST) {
4633a7c4 383 SV* sva;
a3b680e6 384 bool ok = 0;
daba3364 385 for (sva = PL_sv_arenaroot; sva; sva = MUTABLE_SV(SvANY(sva))) {
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AL
386 const SV * const sv = sva + 1;
387 const SV * const svend = &sva[SvREFCNT(sva)];
c0ff570e 388 if (p >= sv && p < svend) {
a0d0e21e 389 ok = 1;
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NC
390 break;
391 }
a0d0e21e
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392 }
393 if (!ok) {
9b387841 394 Perl_ck_warner_d(aTHX_ packWARN(WARN_INTERNAL),
147e3846 395 "Attempt to free non-arena SV: 0x%" UVxf
9b387841 396 pTHX__FORMAT, PTR2UV(p) pTHX__VALUE);
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397 return;
398 }
399 }
4561caa4 400 plant_SV(p);
463ee0b2 401}
a0d0e21e 402
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403#else /* ! DEBUGGING */
404
405#define del_SV(p) plant_SV(p)
406
407#endif /* DEBUGGING */
463ee0b2 408
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409
410/*
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411=head1 SV Manipulation Functions
412
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413=for apidoc sv_add_arena
414
415Given a chunk of memory, link it to the head of the list of arenas,
416and split it into a list of free SVs.
417
418=cut
419*/
420
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NC
421static void
422S_sv_add_arena(pTHX_ char *const ptr, const U32 size, const U32 flags)
463ee0b2 423{
daba3364 424 SV *const sva = MUTABLE_SV(ptr);
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425 SV* sv;
426 SV* svend;
4633a7c4 427
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NC
428 PERL_ARGS_ASSERT_SV_ADD_ARENA;
429
4633a7c4 430 /* The first SV in an arena isn't an SV. */
3280af22 431 SvANY(sva) = (void *) PL_sv_arenaroot; /* ptr to next arena */
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432 SvREFCNT(sva) = size / sizeof(SV); /* number of SV slots */
433 SvFLAGS(sva) = flags; /* FAKE if not to be freed */
434
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435 PL_sv_arenaroot = sva;
436 PL_sv_root = sva + 1;
4633a7c4
LW
437
438 svend = &sva[SvREFCNT(sva) - 1];
439 sv = sva + 1;
463ee0b2 440 while (sv < svend) {
3eef1deb 441 SvARENA_CHAIN_SET(sv, (sv + 1));
03e36789 442#ifdef DEBUGGING
978b032e 443 SvREFCNT(sv) = 0;
03e36789 444#endif
4b69cbe3 445 /* Must always set typemask because it's always checked in on cleanup
03e36789 446 when the arenas are walked looking for objects. */
8990e307 447 SvFLAGS(sv) = SVTYPEMASK;
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448 sv++;
449 }
3eef1deb 450 SvARENA_CHAIN_SET(sv, 0);
03e36789
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451#ifdef DEBUGGING
452 SvREFCNT(sv) = 0;
453#endif
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454 SvFLAGS(sv) = SVTYPEMASK;
455}
456
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457/* visit(): call the named function for each non-free SV in the arenas
458 * whose flags field matches the flags/mask args. */
645c22ef 459
5226ed68 460STATIC I32
de37a194 461S_visit(pTHX_ SVFUNC_t f, const U32 flags, const U32 mask)
8990e307 462{
4633a7c4 463 SV* sva;
5226ed68 464 I32 visited = 0;
8990e307 465
7918f24d
NC
466 PERL_ARGS_ASSERT_VISIT;
467
daba3364 468 for (sva = PL_sv_arenaroot; sva; sva = MUTABLE_SV(SvANY(sva))) {
eb578fdb
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469 const SV * const svend = &sva[SvREFCNT(sva)];
470 SV* sv;
4561caa4 471 for (sv = sva + 1; sv < svend; ++sv) {
e4787c0c 472 if (SvTYPE(sv) != (svtype)SVTYPEMASK
055972dc
DM
473 && (sv->sv_flags & mask) == flags
474 && SvREFCNT(sv))
475 {
942481a7 476 (*f)(aTHX_ sv);
5226ed68
JH
477 ++visited;
478 }
8990e307
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479 }
480 }
5226ed68 481 return visited;
8990e307
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482}
483
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484#ifdef DEBUGGING
485
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486/* called by sv_report_used() for each live SV */
487
488static void
5fa45a31 489do_report_used(pTHX_ SV *const sv)
645c22ef 490{
e4787c0c 491 if (SvTYPE(sv) != (svtype)SVTYPEMASK) {
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DM
492 PerlIO_printf(Perl_debug_log, "****\n");
493 sv_dump(sv);
494 }
495}
758a08c3 496#endif
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497
498/*
499=for apidoc sv_report_used
500
fde67290 501Dump the contents of all SVs not yet freed (debugging aid).
645c22ef
DM
502
503=cut
504*/
505
8990e307 506void
864dbfa3 507Perl_sv_report_used(pTHX)
4561caa4 508{
ff270d3a 509#ifdef DEBUGGING
055972dc 510 visit(do_report_used, 0, 0);
96a5add6
AL
511#else
512 PERL_UNUSED_CONTEXT;
ff270d3a 513#endif
4561caa4
CS
514}
515
645c22ef
DM
516/* called by sv_clean_objs() for each live SV */
517
518static void
de37a194 519do_clean_objs(pTHX_ SV *const ref)
645c22ef 520{
ea724faa
NC
521 assert (SvROK(ref));
522 {
823a54a3
AL
523 SV * const target = SvRV(ref);
524 if (SvOBJECT(target)) {
525 DEBUG_D((PerlIO_printf(Perl_debug_log, "Cleaning object ref:\n "), sv_dump(ref)));
526 if (SvWEAKREF(ref)) {
527 sv_del_backref(target, ref);
528 SvWEAKREF_off(ref);
529 SvRV_set(ref, NULL);
530 } else {
531 SvROK_off(ref);
532 SvRV_set(ref, NULL);
fc2b2dca 533 SvREFCNT_dec_NN(target);
823a54a3 534 }
645c22ef
DM
535 }
536 }
645c22ef
DM
537}
538
645c22ef 539
e4487e9b
DM
540/* clear any slots in a GV which hold objects - except IO;
541 * called by sv_clean_objs() for each live GV */
542
645c22ef 543static void
f30de749 544do_clean_named_objs(pTHX_ SV *const sv)
645c22ef 545{
57ef47cc 546 SV *obj;
ea724faa 547 assert(SvTYPE(sv) == SVt_PVGV);
d011219a 548 assert(isGV_with_GP(sv));
57ef47cc
DM
549 if (!GvGP(sv))
550 return;
551
552 /* freeing GP entries may indirectly free the current GV;
553 * hold onto it while we mess with the GP slots */
554 SvREFCNT_inc(sv);
555
556 if ( ((obj = GvSV(sv) )) && SvOBJECT(obj)) {
557 DEBUG_D((PerlIO_printf(Perl_debug_log,
558 "Cleaning named glob SV object:\n "), sv_dump(obj)));
559 GvSV(sv) = NULL;
fc2b2dca 560 SvREFCNT_dec_NN(obj);
57ef47cc
DM
561 }
562 if ( ((obj = MUTABLE_SV(GvAV(sv)) )) && SvOBJECT(obj)) {
563 DEBUG_D((PerlIO_printf(Perl_debug_log,
564 "Cleaning named glob AV object:\n "), sv_dump(obj)));
565 GvAV(sv) = NULL;
fc2b2dca 566 SvREFCNT_dec_NN(obj);
57ef47cc
DM
567 }
568 if ( ((obj = MUTABLE_SV(GvHV(sv)) )) && SvOBJECT(obj)) {
569 DEBUG_D((PerlIO_printf(Perl_debug_log,
570 "Cleaning named glob HV object:\n "), sv_dump(obj)));
571 GvHV(sv) = NULL;
fc2b2dca 572 SvREFCNT_dec_NN(obj);
57ef47cc
DM
573 }
574 if ( ((obj = MUTABLE_SV(GvCV(sv)) )) && SvOBJECT(obj)) {
575 DEBUG_D((PerlIO_printf(Perl_debug_log,
576 "Cleaning named glob CV object:\n "), sv_dump(obj)));
c43ae56f 577 GvCV_set(sv, NULL);
fc2b2dca 578 SvREFCNT_dec_NN(obj);
57ef47cc 579 }
fc2b2dca 580 SvREFCNT_dec_NN(sv); /* undo the inc above */
e4487e9b
DM
581}
582
68b590d9 583/* clear any IO slots in a GV which hold objects (except stderr, defout);
e4487e9b
DM
584 * called by sv_clean_objs() for each live GV */
585
586static void
587do_clean_named_io_objs(pTHX_ SV *const sv)
588{
e4487e9b
DM
589 SV *obj;
590 assert(SvTYPE(sv) == SVt_PVGV);
591 assert(isGV_with_GP(sv));
68b590d9 592 if (!GvGP(sv) || sv == (SV*)PL_stderrgv || sv == (SV*)PL_defoutgv)
e4487e9b
DM
593 return;
594
595 SvREFCNT_inc(sv);
57ef47cc
DM
596 if ( ((obj = MUTABLE_SV(GvIO(sv)) )) && SvOBJECT(obj)) {
597 DEBUG_D((PerlIO_printf(Perl_debug_log,
598 "Cleaning named glob IO object:\n "), sv_dump(obj)));
599 GvIOp(sv) = NULL;
fc2b2dca 600 SvREFCNT_dec_NN(obj);
645c22ef 601 }
fc2b2dca 602 SvREFCNT_dec_NN(sv); /* undo the inc above */
645c22ef 603}
645c22ef 604
4155e4fe
FC
605/* Void wrapper to pass to visit() */
606static void
607do_curse(pTHX_ SV * const sv) {
c2910e6c
FC
608 if ((PL_stderrgv && GvGP(PL_stderrgv) && (SV*)GvIO(PL_stderrgv) == sv)
609 || (PL_defoutgv && GvGP(PL_defoutgv) && (SV*)GvIO(PL_defoutgv) == sv))
4155e4fe
FC
610 return;
611 (void)curse(sv, 0);
612}
613
645c22ef
DM
614/*
615=for apidoc sv_clean_objs
616
fde67290 617Attempt to destroy all objects not yet freed.
645c22ef
DM
618
619=cut
620*/
621
4561caa4 622void
864dbfa3 623Perl_sv_clean_objs(pTHX)
4561caa4 624{
68b590d9 625 GV *olddef, *olderr;
3280af22 626 PL_in_clean_objs = TRUE;
055972dc 627 visit(do_clean_objs, SVf_ROK, SVf_ROK);
e4487e9b
DM
628 /* Some barnacles may yet remain, clinging to typeglobs.
629 * Run the non-IO destructors first: they may want to output
630 * error messages, close files etc */
d011219a 631 visit(do_clean_named_objs, SVt_PVGV|SVpgv_GP, SVTYPEMASK|SVp_POK|SVpgv_GP);
e4487e9b 632 visit(do_clean_named_io_objs, SVt_PVGV|SVpgv_GP, SVTYPEMASK|SVp_POK|SVpgv_GP);
4155e4fe
FC
633 /* And if there are some very tenacious barnacles clinging to arrays,
634 closures, or what have you.... */
635 visit(do_curse, SVs_OBJECT, SVs_OBJECT);
68b590d9
DM
636 olddef = PL_defoutgv;
637 PL_defoutgv = NULL; /* disable skip of PL_defoutgv */
638 if (olddef && isGV_with_GP(olddef))
639 do_clean_named_io_objs(aTHX_ MUTABLE_SV(olddef));
640 olderr = PL_stderrgv;
641 PL_stderrgv = NULL; /* disable skip of PL_stderrgv */
642 if (olderr && isGV_with_GP(olderr))
643 do_clean_named_io_objs(aTHX_ MUTABLE_SV(olderr));
644 SvREFCNT_dec(olddef);
3280af22 645 PL_in_clean_objs = FALSE;
4561caa4
CS
646}
647
645c22ef
DM
648/* called by sv_clean_all() for each live SV */
649
650static void
de37a194 651do_clean_all(pTHX_ SV *const sv)
645c22ef 652{
daba3364 653 if (sv == (const SV *) PL_fdpid || sv == (const SV *)PL_strtab) {
cddfcddc 654 /* don't clean pid table and strtab */
d17ea597 655 return;
cddfcddc 656 }
147e3846 657 DEBUG_D((PerlIO_printf(Perl_debug_log, "Cleaning loops: SV at 0x%" UVxf "\n", PTR2UV(sv)) ));
645c22ef 658 SvFLAGS(sv) |= SVf_BREAK;
fc2b2dca 659 SvREFCNT_dec_NN(sv);
645c22ef
DM
660}
661
662/*
663=for apidoc sv_clean_all
664
665Decrement the refcnt of each remaining SV, possibly triggering a
fde67290 666cleanup. This function may have to be called multiple times to free
ff276b08 667SVs which are in complex self-referential hierarchies.
645c22ef
DM
668
669=cut
670*/
671
5226ed68 672I32
864dbfa3 673Perl_sv_clean_all(pTHX)
8990e307 674{
5226ed68 675 I32 cleaned;
3280af22 676 PL_in_clean_all = TRUE;
055972dc 677 cleaned = visit(do_clean_all, 0,0);
5226ed68 678 return cleaned;
8990e307 679}
463ee0b2 680
5e258f8c
JC
681/*
682 ARENASETS: a meta-arena implementation which separates arena-info
683 into struct arena_set, which contains an array of struct
684 arena_descs, each holding info for a single arena. By separating
685 the meta-info from the arena, we recover the 1st slot, formerly
686 borrowed for list management. The arena_set is about the size of an
39244528 687 arena, avoiding the needless malloc overhead of a naive linked-list.
5e258f8c
JC
688
689 The cost is 1 arena-set malloc per ~320 arena-mallocs, + the unused
690 memory in the last arena-set (1/2 on average). In trade, we get
691 back the 1st slot in each arena (ie 1.7% of a CV-arena, less for
d2a0f284 692 smaller types). The recovery of the wasted space allows use of
e15dad31
JC
693 small arenas for large, rare body types, by changing array* fields
694 in body_details_by_type[] below.
5e258f8c 695*/
5e258f8c 696struct arena_desc {
398c677b
NC
697 char *arena; /* the raw storage, allocated aligned */
698 size_t size; /* its size ~4k typ */
e5973ed5 699 svtype utype; /* bodytype stored in arena */
5e258f8c
JC
700};
701
e6148039
NC
702struct arena_set;
703
704/* Get the maximum number of elements in set[] such that struct arena_set
e15dad31 705 will fit within PERL_ARENA_SIZE, which is probably just under 4K, and
e6148039
NC
706 therefore likely to be 1 aligned memory page. */
707
708#define ARENAS_PER_SET ((PERL_ARENA_SIZE - sizeof(struct arena_set*) \
709 - 2 * sizeof(int)) / sizeof (struct arena_desc))
5e258f8c
JC
710
711struct arena_set {
712 struct arena_set* next;
0a848332
NC
713 unsigned int set_size; /* ie ARENAS_PER_SET */
714 unsigned int curr; /* index of next available arena-desc */
5e258f8c
JC
715 struct arena_desc set[ARENAS_PER_SET];
716};
717
645c22ef
DM
718/*
719=for apidoc sv_free_arenas
720
fde67290 721Deallocate the memory used by all arenas. Note that all the individual SV
645c22ef
DM
722heads and bodies within the arenas must already have been freed.
723
724=cut
7fefc6c1 725
645c22ef 726*/
4633a7c4 727void
864dbfa3 728Perl_sv_free_arenas(pTHX)
4633a7c4
LW
729{
730 SV* sva;
731 SV* svanext;
0a848332 732 unsigned int i;
4633a7c4
LW
733
734 /* Free arenas here, but be careful about fake ones. (We assume
735 contiguity of the fake ones with the corresponding real ones.) */
736
3280af22 737 for (sva = PL_sv_arenaroot; sva; sva = svanext) {
daba3364 738 svanext = MUTABLE_SV(SvANY(sva));
4633a7c4 739 while (svanext && SvFAKE(svanext))
daba3364 740 svanext = MUTABLE_SV(SvANY(svanext));
4633a7c4
LW
741
742 if (!SvFAKE(sva))
1df70142 743 Safefree(sva);
4633a7c4 744 }
93e68bfb 745
5e258f8c 746 {
0a848332
NC
747 struct arena_set *aroot = (struct arena_set*) PL_body_arenas;
748
749 while (aroot) {
750 struct arena_set *current = aroot;
751 i = aroot->curr;
752 while (i--) {
5e258f8c
JC
753 assert(aroot->set[i].arena);
754 Safefree(aroot->set[i].arena);
755 }
0a848332
NC
756 aroot = aroot->next;
757 Safefree(current);
5e258f8c
JC
758 }
759 }
dc8220bf 760 PL_body_arenas = 0;
fdda85ca 761
0a848332
NC
762 i = PERL_ARENA_ROOTS_SIZE;
763 while (i--)
93e68bfb 764 PL_body_roots[i] = 0;
93e68bfb 765
3280af22
NIS
766 PL_sv_arenaroot = 0;
767 PL_sv_root = 0;
4633a7c4
LW
768}
769
bd81e77b
NC
770/*
771 Here are mid-level routines that manage the allocation of bodies out
772 of the various arenas. There are 5 kinds of arenas:
29489e7c 773
bd81e77b
NC
774 1. SV-head arenas, which are discussed and handled above
775 2. regular body arenas
776 3. arenas for reduced-size bodies
777 4. Hash-Entry arenas
29489e7c 778
bd81e77b
NC
779 Arena types 2 & 3 are chained by body-type off an array of
780 arena-root pointers, which is indexed by svtype. Some of the
781 larger/less used body types are malloced singly, since a large
782 unused block of them is wasteful. Also, several svtypes dont have
783 bodies; the data fits into the sv-head itself. The arena-root
784 pointer thus has a few unused root-pointers (which may be hijacked
785 later for arena types 4,5)
29489e7c 786
bd81e77b
NC
787 3 differs from 2 as an optimization; some body types have several
788 unused fields in the front of the structure (which are kept in-place
789 for consistency). These bodies can be allocated in smaller chunks,
790 because the leading fields arent accessed. Pointers to such bodies
791 are decremented to point at the unused 'ghost' memory, knowing that
792 the pointers are used with offsets to the real memory.
29489e7c 793
d2a0f284
JC
794
795=head1 SV-Body Allocation
796
f554dfc5
MH
797=cut
798
d2a0f284
JC
799Allocation of SV-bodies is similar to SV-heads, differing as follows;
800the allocation mechanism is used for many body types, so is somewhat
801more complicated, it uses arena-sets, and has no need for still-live
802SV detection.
803
804At the outermost level, (new|del)_X*V macros return bodies of the
805appropriate type. These macros call either (new|del)_body_type or
806(new|del)_body_allocated macro pairs, depending on specifics of the
807type. Most body types use the former pair, the latter pair is used to
808allocate body types with "ghost fields".
809
810"ghost fields" are fields that are unused in certain types, and
69ba284b 811consequently don't need to actually exist. They are declared because
d2a0f284
JC
812they're part of a "base type", which allows use of functions as
813methods. The simplest examples are AVs and HVs, 2 aggregate types
814which don't use the fields which support SCALAR semantics.
815
69ba284b 816For these types, the arenas are carved up into appropriately sized
d2a0f284
JC
817chunks, we thus avoid wasted memory for those unaccessed members.
818When bodies are allocated, we adjust the pointer back in memory by the
69ba284b 819size of the part not allocated, so it's as if we allocated the full
d2a0f284
JC
820structure. (But things will all go boom if you write to the part that
821is "not there", because you'll be overwriting the last members of the
822preceding structure in memory.)
823
69ba284b 824We calculate the correction using the STRUCT_OFFSET macro on the first
a05ea1cf 825member present. If the allocated structure is smaller (no initial NV
69ba284b
NC
826actually allocated) then the net effect is to subtract the size of the NV
827from the pointer, to return a new pointer as if an initial NV were actually
a05ea1cf 828allocated. (We were using structures named *_allocated for this, but
69ba284b
NC
829this turned out to be a subtle bug, because a structure without an NV
830could have a lower alignment constraint, but the compiler is allowed to
831optimised accesses based on the alignment constraint of the actual pointer
832to the full structure, for example, using a single 64 bit load instruction
833because it "knows" that two adjacent 32 bit members will be 8-byte aligned.)
d2a0f284 834
a05ea1cf 835This is the same trick as was used for NV and IV bodies. Ironically it
d2a0f284 836doesn't need to be used for NV bodies any more, because NV is now at
5b306eef
DD
837the start of the structure. IV bodies, and also in some builds NV bodies,
838don't need it either, because they are no longer allocated.
d2a0f284
JC
839
840In turn, the new_body_* allocators call S_new_body(), which invokes
841new_body_inline macro, which takes a lock, and takes a body off the
1e30fcd5 842linked list at PL_body_roots[sv_type], calling Perl_more_bodies() if
d2a0f284
JC
843necessary to refresh an empty list. Then the lock is released, and
844the body is returned.
845
99816f8d 846Perl_more_bodies allocates a new arena, and carves it up into an array of N
d2a0f284
JC
847bodies, which it strings into a linked list. It looks up arena-size
848and body-size from the body_details table described below, thus
849supporting the multiple body-types.
850
851If PURIFY is defined, or PERL_ARENA_SIZE=0, arenas are not used, and
852the (new|del)_X*V macros are mapped directly to malloc/free.
853
d2a0f284
JC
854For each sv-type, struct body_details bodies_by_type[] carries
855parameters which control these aspects of SV handling:
856
857Arena_size determines whether arenas are used for this body type, and if
858so, how big they are. PURIFY or PERL_ARENA_SIZE=0 set this field to
859zero, forcing individual mallocs and frees.
860
861Body_size determines how big a body is, and therefore how many fit into
862each arena. Offset carries the body-pointer adjustment needed for
69ba284b 863"ghost fields", and is used in *_allocated macros.
d2a0f284
JC
864
865But its main purpose is to parameterize info needed in
866Perl_sv_upgrade(). The info here dramatically simplifies the function
69ba284b 867vs the implementation in 5.8.8, making it table-driven. All fields
d2a0f284
JC
868are used for this, except for arena_size.
869
870For the sv-types that have no bodies, arenas are not used, so those
871PL_body_roots[sv_type] are unused, and can be overloaded. In
872something of a special case, SVt_NULL is borrowed for HE arenas;
c6f8b1d0 873PL_body_roots[HE_SVSLOT=SVt_NULL] is filled by S_more_he, but the
d2a0f284 874bodies_by_type[SVt_NULL] slot is not used, as the table is not
c6f8b1d0 875available in hv.c.
d2a0f284 876
29489e7c
DM
877*/
878
bd81e77b 879struct body_details {
0fb58b32 880 U8 body_size; /* Size to allocate */
10666ae3 881 U8 copy; /* Size of structure to copy (may be shorter) */
5b306eef
DD
882 U8 offset; /* Size of unalloced ghost fields to first alloced field*/
883 PERL_BITFIELD8 type : 4; /* We have space for a sanity check. */
884 PERL_BITFIELD8 cant_upgrade : 1;/* Cannot upgrade this type */
885 PERL_BITFIELD8 zero_nv : 1; /* zero the NV when upgrading from this */
886 PERL_BITFIELD8 arena : 1; /* Allocated from an arena */
887 U32 arena_size; /* Size of arena to allocate */
bd81e77b 888};
29489e7c 889
bd81e77b
NC
890#define HADNV FALSE
891#define NONV TRUE
29489e7c 892
d2a0f284 893
bd81e77b
NC
894#ifdef PURIFY
895/* With -DPURFIY we allocate everything directly, and don't use arenas.
896 This seems a rather elegant way to simplify some of the code below. */
897#define HASARENA FALSE
898#else
899#define HASARENA TRUE
900#endif
901#define NOARENA FALSE
29489e7c 902
d2a0f284
JC
903/* Size the arenas to exactly fit a given number of bodies. A count
904 of 0 fits the max number bodies into a PERL_ARENA_SIZE.block,
905 simplifying the default. If count > 0, the arena is sized to fit
906 only that many bodies, allowing arenas to be used for large, rare
907 bodies (XPVFM, XPVIO) without undue waste. The arena size is
908 limited by PERL_ARENA_SIZE, so we can safely oversize the
909 declarations.
910 */
95db5f15
MB
911#define FIT_ARENA0(body_size) \
912 ((size_t)(PERL_ARENA_SIZE / body_size) * body_size)
913#define FIT_ARENAn(count,body_size) \
914 ( count * body_size <= PERL_ARENA_SIZE) \
915 ? count * body_size \
916 : FIT_ARENA0 (body_size)
917#define FIT_ARENA(count,body_size) \
cd1dc8e2 918 (U32)(count \
95db5f15 919 ? FIT_ARENAn (count, body_size) \
cd1dc8e2 920 : FIT_ARENA0 (body_size))
d2a0f284 921
bd81e77b
NC
922/* Calculate the length to copy. Specifically work out the length less any
923 final padding the compiler needed to add. See the comment in sv_upgrade
924 for why copying the padding proved to be a bug. */
29489e7c 925
bd81e77b
NC
926#define copy_length(type, last_member) \
927 STRUCT_OFFSET(type, last_member) \
daba3364 928 + sizeof (((type*)SvANY((const SV *)0))->last_member)
29489e7c 929
bd81e77b 930static const struct body_details bodies_by_type[] = {
829cd18a
NC
931 /* HEs use this offset for their arena. */
932 { 0, 0, 0, SVt_NULL, FALSE, NONV, NOARENA, 0 },
d2a0f284 933
db93c0c4
NC
934 /* IVs are in the head, so the allocation size is 0. */
935 { 0,
d2a0f284 936 sizeof(IV), /* This is used to copy out the IV body. */
10666ae3 937 STRUCT_OFFSET(XPVIV, xiv_iv), SVt_IV, FALSE, NONV,
db93c0c4 938 NOARENA /* IVS don't need an arena */, 0
d2a0f284
JC
939 },
940
5b306eef
DD
941#if NVSIZE <= IVSIZE
942 { 0, sizeof(NV),
943 STRUCT_OFFSET(XPVNV, xnv_u),
944 SVt_NV, FALSE, HADNV, NOARENA, 0 },
945#else
6e128786
NC
946 { sizeof(NV), sizeof(NV),
947 STRUCT_OFFSET(XPVNV, xnv_u),
948 SVt_NV, FALSE, HADNV, HASARENA, FIT_ARENA(0, sizeof(NV)) },
5b306eef 949#endif
d2a0f284 950
bc337e5c 951 { sizeof(XPV) - STRUCT_OFFSET(XPV, xpv_cur),
889d28b2
NC
952 copy_length(XPV, xpv_len) - STRUCT_OFFSET(XPV, xpv_cur),
953 + STRUCT_OFFSET(XPV, xpv_cur),
69ba284b 954 SVt_PV, FALSE, NONV, HASARENA,
889d28b2 955 FIT_ARENA(0, sizeof(XPV) - STRUCT_OFFSET(XPV, xpv_cur)) },
d2a0f284 956
d361b004
KW
957 { sizeof(XINVLIST) - STRUCT_OFFSET(XPV, xpv_cur),
958 copy_length(XINVLIST, is_offset) - STRUCT_OFFSET(XPV, xpv_cur),
959 + STRUCT_OFFSET(XPV, xpv_cur),
960 SVt_INVLIST, TRUE, NONV, HASARENA,
961 FIT_ARENA(0, sizeof(XINVLIST) - STRUCT_OFFSET(XPV, xpv_cur)) },
e94d9b54 962
bc337e5c 963 { sizeof(XPVIV) - STRUCT_OFFSET(XPV, xpv_cur),
889d28b2
NC
964 copy_length(XPVIV, xiv_u) - STRUCT_OFFSET(XPV, xpv_cur),
965 + STRUCT_OFFSET(XPV, xpv_cur),
966 SVt_PVIV, FALSE, NONV, HASARENA,
967 FIT_ARENA(0, sizeof(XPVIV) - STRUCT_OFFSET(XPV, xpv_cur)) },
d2a0f284 968
bc337e5c 969 { sizeof(XPVNV) - STRUCT_OFFSET(XPV, xpv_cur),
889d28b2
NC
970 copy_length(XPVNV, xnv_u) - STRUCT_OFFSET(XPV, xpv_cur),
971 + STRUCT_OFFSET(XPV, xpv_cur),
972 SVt_PVNV, FALSE, HADNV, HASARENA,
973 FIT_ARENA(0, sizeof(XPVNV) - STRUCT_OFFSET(XPV, xpv_cur)) },
d2a0f284 974
6e128786 975 { sizeof(XPVMG), copy_length(XPVMG, xnv_u), 0, SVt_PVMG, FALSE, HADNV,
d2a0f284 976 HASARENA, FIT_ARENA(0, sizeof(XPVMG)) },
4df7f6af 977
601dfd0a
NC
978 { sizeof(regexp),
979 sizeof(regexp),
980 0,
ecff11eb 981 SVt_REGEXP, TRUE, NONV, HASARENA,
eaeb1e7f 982 FIT_ARENA(0, sizeof(regexp))
5c35adbb 983 },
4df7f6af 984
10666ae3 985 { sizeof(XPVGV), sizeof(XPVGV), 0, SVt_PVGV, TRUE, HADNV,
d2a0f284
JC
986 HASARENA, FIT_ARENA(0, sizeof(XPVGV)) },
987
10666ae3 988 { sizeof(XPVLV), sizeof(XPVLV), 0, SVt_PVLV, TRUE, HADNV,
d2a0f284
JC
989 HASARENA, FIT_ARENA(0, sizeof(XPVLV)) },
990
601dfd0a 991 { sizeof(XPVAV),
4f7003f5 992 copy_length(XPVAV, xav_alloc),
601dfd0a 993 0,
69ba284b 994 SVt_PVAV, TRUE, NONV, HASARENA,
601dfd0a 995 FIT_ARENA(0, sizeof(XPVAV)) },
d2a0f284 996
601dfd0a 997 { sizeof(XPVHV),
359164a0 998 copy_length(XPVHV, xhv_max),
601dfd0a 999 0,
69ba284b 1000 SVt_PVHV, TRUE, NONV, HASARENA,
601dfd0a 1001 FIT_ARENA(0, sizeof(XPVHV)) },
d2a0f284 1002
601dfd0a
NC
1003 { sizeof(XPVCV),
1004 sizeof(XPVCV),
1005 0,
69ba284b 1006 SVt_PVCV, TRUE, NONV, HASARENA,
601dfd0a 1007 FIT_ARENA(0, sizeof(XPVCV)) },
69ba284b 1008
601dfd0a
NC
1009 { sizeof(XPVFM),
1010 sizeof(XPVFM),
1011 0,
69ba284b 1012 SVt_PVFM, TRUE, NONV, NOARENA,
601dfd0a 1013 FIT_ARENA(20, sizeof(XPVFM)) },
d2a0f284 1014
601dfd0a
NC
1015 { sizeof(XPVIO),
1016 sizeof(XPVIO),
1017 0,
b6f60916 1018 SVt_PVIO, TRUE, NONV, HASARENA,
601dfd0a 1019 FIT_ARENA(24, sizeof(XPVIO)) },
bd81e77b 1020};
29489e7c 1021
bd81e77b 1022#define new_body_allocated(sv_type) \
d2a0f284 1023 (void *)((char *)S_new_body(aTHX_ sv_type) \
bd81e77b 1024 - bodies_by_type[sv_type].offset)
29489e7c 1025
26359cfa
NC
1026/* return a thing to the free list */
1027
1028#define del_body(thing, root) \
1029 STMT_START { \
1030 void ** const thing_copy = (void **)thing; \
1031 *thing_copy = *root; \
1032 *root = (void*)thing_copy; \
1033 } STMT_END
29489e7c 1034
bd81e77b 1035#ifdef PURIFY
5b306eef
DD
1036#if !(NVSIZE <= IVSIZE)
1037# define new_XNV() safemalloc(sizeof(XPVNV))
1038#endif
beeec492
NC
1039#define new_XPVNV() safemalloc(sizeof(XPVNV))
1040#define new_XPVMG() safemalloc(sizeof(XPVMG))
29489e7c 1041
beeec492 1042#define del_XPVGV(p) safefree(p)
29489e7c 1043
bd81e77b 1044#else /* !PURIFY */
29489e7c 1045
5b306eef
DD
1046#if !(NVSIZE <= IVSIZE)
1047# define new_XNV() new_body_allocated(SVt_NV)
1048#endif
65ac1738 1049#define new_XPVNV() new_body_allocated(SVt_PVNV)
65ac1738 1050#define new_XPVMG() new_body_allocated(SVt_PVMG)
645c22ef 1051
26359cfa
NC
1052#define del_XPVGV(p) del_body(p + bodies_by_type[SVt_PVGV].offset, \
1053 &PL_body_roots[SVt_PVGV])
1d7c1841 1054
bd81e77b 1055#endif /* PURIFY */
93e68bfb 1056
bd81e77b 1057/* no arena for you! */
93e68bfb 1058
bd81e77b 1059#define new_NOARENA(details) \
beeec492 1060 safemalloc((details)->body_size + (details)->offset)
bd81e77b 1061#define new_NOARENAZ(details) \
beeec492 1062 safecalloc((details)->body_size + (details)->offset, 1)
d2a0f284 1063
1e30fcd5
NC
1064void *
1065Perl_more_bodies (pTHX_ const svtype sv_type, const size_t body_size,
1066 const size_t arena_size)
d2a0f284 1067{
d2a0f284 1068 void ** const root = &PL_body_roots[sv_type];
99816f8d
NC
1069 struct arena_desc *adesc;
1070 struct arena_set *aroot = (struct arena_set *) PL_body_arenas;
1071 unsigned int curr;
d2a0f284
JC
1072 char *start;
1073 const char *end;
02982131 1074 const size_t good_arena_size = Perl_malloc_good_size(arena_size);
20b7effb
JH
1075#if defined(DEBUGGING) && defined(PERL_GLOBAL_STRUCT)
1076 dVAR;
1077#endif
0b2d3faa 1078#if defined(DEBUGGING) && !defined(PERL_GLOBAL_STRUCT_PRIVATE)
23e9d66c
NC
1079 static bool done_sanity_check;
1080
0b2d3faa
JH
1081 /* PERL_GLOBAL_STRUCT_PRIVATE cannot coexist with global
1082 * variables like done_sanity_check. */
10666ae3 1083 if (!done_sanity_check) {
ea471437 1084 unsigned int i = SVt_LAST;
10666ae3
NC
1085
1086 done_sanity_check = TRUE;
1087
1088 while (i--)
1089 assert (bodies_by_type[i].type == i);
1090 }
1091#endif
1092
02982131 1093 assert(arena_size);
23e9d66c 1094
99816f8d
NC
1095 /* may need new arena-set to hold new arena */
1096 if (!aroot || aroot->curr >= aroot->set_size) {
1097 struct arena_set *newroot;
1098 Newxz(newroot, 1, struct arena_set);
1099 newroot->set_size = ARENAS_PER_SET;
1100 newroot->next = aroot;
1101 aroot = newroot;
1102 PL_body_arenas = (void *) newroot;
1103 DEBUG_m(PerlIO_printf(Perl_debug_log, "new arenaset %p\n", (void*)aroot));
1104 }
1105
1106 /* ok, now have arena-set with at least 1 empty/available arena-desc */
1107 curr = aroot->curr++;
1108 adesc = &(aroot->set[curr]);
1109 assert(!adesc->arena);
1110
1111 Newx(adesc->arena, good_arena_size, char);
1112 adesc->size = good_arena_size;
1113 adesc->utype = sv_type;
147e3846 1114 DEBUG_m(PerlIO_printf(Perl_debug_log, "arena %d added: %p size %" UVuf "\n",
99816f8d
NC
1115 curr, (void*)adesc->arena, (UV)good_arena_size));
1116
1117 start = (char *) adesc->arena;
d2a0f284 1118
29657bb6
NC
1119 /* Get the address of the byte after the end of the last body we can fit.
1120 Remember, this is integer division: */
02982131 1121 end = start + good_arena_size / body_size * body_size;
d2a0f284 1122
486ec47a 1123 /* computed count doesn't reflect the 1st slot reservation */
d8fca402
NC
1124#if defined(MYMALLOC) || defined(HAS_MALLOC_GOOD_SIZE)
1125 DEBUG_m(PerlIO_printf(Perl_debug_log,
1126 "arena %p end %p arena-size %d (from %d) type %d "
1127 "size %d ct %d\n",
02982131
NC
1128 (void*)start, (void*)end, (int)good_arena_size,
1129 (int)arena_size, sv_type, (int)body_size,
1130 (int)good_arena_size / (int)body_size));
d8fca402 1131#else
d2a0f284
JC
1132 DEBUG_m(PerlIO_printf(Perl_debug_log,
1133 "arena %p end %p arena-size %d type %d size %d ct %d\n",
6c9570dc 1134 (void*)start, (void*)end,
02982131
NC
1135 (int)arena_size, sv_type, (int)body_size,
1136 (int)good_arena_size / (int)body_size));
d8fca402 1137#endif
d2a0f284
JC
1138 *root = (void *)start;
1139
29657bb6
NC
1140 while (1) {
1141 /* Where the next body would start: */
d2a0f284 1142 char * const next = start + body_size;
29657bb6
NC
1143
1144 if (next >= end) {
1145 /* This is the last body: */
1146 assert(next == end);
1147
1148 *(void **)start = 0;
1149 return *root;
1150 }
1151
d2a0f284
JC
1152 *(void**) start = (void *)next;
1153 start = next;
1154 }
d2a0f284
JC
1155}
1156
1157/* grab a new thing from the free list, allocating more if necessary.
1158 The inline version is used for speed in hot routines, and the
1159 function using it serves the rest (unless PURIFY).
1160*/
1161#define new_body_inline(xpv, sv_type) \
1162 STMT_START { \
1163 void ** const r3wt = &PL_body_roots[sv_type]; \
11b79775 1164 xpv = (PTR_TBL_ENT_t*) (*((void **)(r3wt)) \
1e30fcd5 1165 ? *((void **)(r3wt)) : Perl_more_bodies(aTHX_ sv_type, \
02982131
NC
1166 bodies_by_type[sv_type].body_size,\
1167 bodies_by_type[sv_type].arena_size)); \
d2a0f284 1168 *(r3wt) = *(void**)(xpv); \
d2a0f284
JC
1169 } STMT_END
1170
1171#ifndef PURIFY
1172
1173STATIC void *
de37a194 1174S_new_body(pTHX_ const svtype sv_type)
d2a0f284 1175{
d2a0f284
JC
1176 void *xpv;
1177 new_body_inline(xpv, sv_type);
1178 return xpv;
1179}
1180
1181#endif
93e68bfb 1182
238b27b3
NC
1183static const struct body_details fake_rv =
1184 { 0, 0, 0, SVt_IV, FALSE, NONV, NOARENA, 0 };
1185
bd81e77b
NC
1186/*
1187=for apidoc sv_upgrade
93e68bfb 1188
bd81e77b
NC
1189Upgrade an SV to a more complex form. Generally adds a new body type to the
1190SV, then copies across as much information as possible from the old body.
9521ca61
FC
1191It croaks if the SV is already in a more complex form than requested. You
1192generally want to use the C<SvUPGRADE> macro wrapper, which checks the type
1193before calling C<sv_upgrade>, and hence does not croak. See also
fbe13c60 1194C<L</svtype>>.
93e68bfb 1195
bd81e77b 1196=cut
93e68bfb 1197*/
93e68bfb 1198
bd81e77b 1199void
5aaab254 1200Perl_sv_upgrade(pTHX_ SV *const sv, svtype new_type)
cac9b346 1201{
bd81e77b
NC
1202 void* old_body;
1203 void* new_body;
42d0e0b7 1204 const svtype old_type = SvTYPE(sv);
d2a0f284 1205 const struct body_details *new_type_details;
238b27b3 1206 const struct body_details *old_type_details
bd81e77b 1207 = bodies_by_type + old_type;
ed7df46e 1208 SV *referent = NULL;
cac9b346 1209
7918f24d
NC
1210 PERL_ARGS_ASSERT_SV_UPGRADE;
1211
1776cbe8
NC
1212 if (old_type == new_type)
1213 return;
1214
1215 /* This clause was purposefully added ahead of the early return above to
1216 the shared string hackery for (sort {$a <=> $b} keys %hash), with the
1217 inference by Nick I-S that it would fix other troublesome cases. See
1218 changes 7162, 7163 (f130fd4589cf5fbb24149cd4db4137c8326f49c1 and parent)
1219
1220 Given that shared hash key scalars are no longer PVIV, but PV, there is
1221 no longer need to unshare so as to free up the IVX slot for its proper
1222 purpose. So it's safe to move the early return earlier. */
1223
093085a8 1224 if (new_type > SVt_PVMG && SvIsCOW(sv)) {
bd81e77b
NC
1225 sv_force_normal_flags(sv, 0);
1226 }
cac9b346 1227
bd81e77b 1228 old_body = SvANY(sv);
de042e1d 1229
bd81e77b
NC
1230 /* Copying structures onto other structures that have been neatly zeroed
1231 has a subtle gotcha. Consider XPVMG
cac9b346 1232
bd81e77b
NC
1233 +------+------+------+------+------+-------+-------+
1234 | NV | CUR | LEN | IV | MAGIC | STASH |
1235 +------+------+------+------+------+-------+-------+
1236 0 4 8 12 16 20 24 28
645c22ef 1237
bd81e77b
NC
1238 where NVs are aligned to 8 bytes, so that sizeof that structure is
1239 actually 32 bytes long, with 4 bytes of padding at the end:
08742458 1240
bd81e77b
NC
1241 +------+------+------+------+------+-------+-------+------+
1242 | NV | CUR | LEN | IV | MAGIC | STASH | ??? |
1243 +------+------+------+------+------+-------+-------+------+
1244 0 4 8 12 16 20 24 28 32
08742458 1245
bd81e77b 1246 so what happens if you allocate memory for this structure:
30f9da9e 1247
bd81e77b
NC
1248 +------+------+------+------+------+-------+-------+------+------+...
1249 | NV | CUR | LEN | IV | MAGIC | STASH | GP | NAME |
1250 +------+------+------+------+------+-------+-------+------+------+...
1251 0 4 8 12 16 20 24 28 32 36
bfc44f79 1252
bd81e77b
NC
1253 zero it, then copy sizeof(XPVMG) bytes on top of it? Not quite what you
1254 expect, because you copy the area marked ??? onto GP. Now, ??? may have
1255 started out as zero once, but it's quite possible that it isn't. So now,
1256 rather than a nicely zeroed GP, you have it pointing somewhere random.
1257 Bugs ensue.
bfc44f79 1258
bd81e77b
NC
1259 (In fact, GP ends up pointing at a previous GP structure, because the
1260 principle cause of the padding in XPVMG getting garbage is a copy of
6c9e42f7
NC
1261 sizeof(XPVMG) bytes from a XPVGV structure in sv_unglob. Right now
1262 this happens to be moot because XPVGV has been re-ordered, with GP
1263 no longer after STASH)
30f9da9e 1264
bd81e77b
NC
1265 So we are careful and work out the size of used parts of all the
1266 structures. */
bfc44f79 1267
bd81e77b
NC
1268 switch (old_type) {
1269 case SVt_NULL:
1270 break;
1271 case SVt_IV:
4df7f6af 1272 if (SvROK(sv)) {
ed7df46e 1273 referent = SvRV(sv);
238b27b3
NC
1274 old_type_details = &fake_rv;
1275 if (new_type == SVt_NV)
1276 new_type = SVt_PVNV;
4df7f6af
NC
1277 } else {
1278 if (new_type < SVt_PVIV) {
1279 new_type = (new_type == SVt_NV)
1280 ? SVt_PVNV : SVt_PVIV;
1281 }
bd81e77b
NC
1282 }
1283 break;
1284 case SVt_NV:
1285 if (new_type < SVt_PVNV) {
1286 new_type = SVt_PVNV;
bd81e77b
NC
1287 }
1288 break;
bd81e77b
NC
1289 case SVt_PV:
1290 assert(new_type > SVt_PV);
6d59e610
LM
1291 STATIC_ASSERT_STMT(SVt_IV < SVt_PV);
1292 STATIC_ASSERT_STMT(SVt_NV < SVt_PV);
bd81e77b
NC
1293 break;
1294 case SVt_PVIV:
1295 break;
1296 case SVt_PVNV:
1297 break;
1298 case SVt_PVMG:
1299 /* Because the XPVMG of PL_mess_sv isn't allocated from the arena,
1300 there's no way that it can be safely upgraded, because perl.c
1301 expects to Safefree(SvANY(PL_mess_sv)) */
1302 assert(sv != PL_mess_sv);
bd81e77b
NC
1303 break;
1304 default:
2439e033 1305 if (UNLIKELY(old_type_details->cant_upgrade))
c81225bc
NC
1306 Perl_croak(aTHX_ "Can't upgrade %s (%" UVuf ") to %" UVuf,
1307 sv_reftype(sv, 0), (UV) old_type, (UV) new_type);
bd81e77b 1308 }
3376de98 1309
2439e033 1310 if (UNLIKELY(old_type > new_type))
3376de98
NC
1311 Perl_croak(aTHX_ "sv_upgrade from type %d down to type %d",
1312 (int)old_type, (int)new_type);
1313
2fa1109b 1314 new_type_details = bodies_by_type + new_type;
645c22ef 1315
bd81e77b
NC
1316 SvFLAGS(sv) &= ~SVTYPEMASK;
1317 SvFLAGS(sv) |= new_type;
932e9ff9 1318
ab4416c0
NC
1319 /* This can't happen, as SVt_NULL is <= all values of new_type, so one of
1320 the return statements above will have triggered. */
1321 assert (new_type != SVt_NULL);
bd81e77b 1322 switch (new_type) {
bd81e77b
NC
1323 case SVt_IV:
1324 assert(old_type == SVt_NULL);
dc6369ef 1325 SET_SVANY_FOR_BODYLESS_IV(sv);
bd81e77b
NC
1326 SvIV_set(sv, 0);
1327 return;
1328 case SVt_NV:
1329 assert(old_type == SVt_NULL);
5b306eef 1330#if NVSIZE <= IVSIZE
dc6369ef 1331 SET_SVANY_FOR_BODYLESS_NV(sv);
5b306eef 1332#else
bd81e77b 1333 SvANY(sv) = new_XNV();
5b306eef 1334#endif
bd81e77b
NC
1335 SvNV_set(sv, 0);
1336 return;
bd81e77b 1337 case SVt_PVHV:
bd81e77b 1338 case SVt_PVAV:
d2a0f284 1339 assert(new_type_details->body_size);
c1ae03ae
NC
1340
1341#ifndef PURIFY
1342 assert(new_type_details->arena);
d2a0f284 1343 assert(new_type_details->arena_size);
c1ae03ae 1344 /* This points to the start of the allocated area. */
d2a0f284
JC
1345 new_body_inline(new_body, new_type);
1346 Zero(new_body, new_type_details->body_size, char);
c1ae03ae
NC
1347 new_body = ((char *)new_body) - new_type_details->offset;
1348#else
1349 /* We always allocated the full length item with PURIFY. To do this
1350 we fake things so that arena is false for all 16 types.. */
1351 new_body = new_NOARENAZ(new_type_details);
1352#endif
1353 SvANY(sv) = new_body;
1354 if (new_type == SVt_PVAV) {
1355 AvMAX(sv) = -1;
1356 AvFILLp(sv) = -1;
1357 AvREAL_only(sv);
64484faa 1358 if (old_type_details->body_size) {
ac572bf4
NC
1359 AvALLOC(sv) = 0;
1360 } else {
1361 /* It will have been zeroed when the new body was allocated.
1362 Lets not write to it, in case it confuses a write-back
1363 cache. */
1364 }
78ac7dd9
NC
1365 } else {
1366 assert(!SvOK(sv));
1367 SvOK_off(sv);
1368#ifndef NODEFAULT_SHAREKEYS
1369 HvSHAREKEYS_on(sv); /* key-sharing on by default */
1370#endif
586fc6a3
SM
1371 /* start with PERL_HASH_DEFAULT_HvMAX+1 buckets: */
1372 HvMAX(sv) = PERL_HASH_DEFAULT_HvMAX;
c1ae03ae 1373 }
aeb18a1e 1374
bd81e77b
NC
1375 /* SVt_NULL isn't the only thing upgraded to AV or HV.
1376 The target created by newSVrv also is, and it can have magic.
1377 However, it never has SvPVX set.
1378 */
4df7f6af
NC
1379 if (old_type == SVt_IV) {
1380 assert(!SvROK(sv));
1381 } else if (old_type >= SVt_PV) {
bd81e77b
NC
1382 assert(SvPVX_const(sv) == 0);
1383 }
aeb18a1e 1384
bd81e77b 1385 if (old_type >= SVt_PVMG) {
e736a858 1386 SvMAGIC_set(sv, ((XPVMG*)old_body)->xmg_u.xmg_magic);
bd81e77b 1387 SvSTASH_set(sv, ((XPVMG*)old_body)->xmg_stash);
797c7171
NC
1388 } else {
1389 sv->sv_u.svu_array = NULL; /* or svu_hash */
bd81e77b
NC
1390 }
1391 break;
93e68bfb 1392
bd81e77b
NC
1393 case SVt_PVIV:
1394 /* XXX Is this still needed? Was it ever needed? Surely as there is
1395 no route from NV to PVIV, NOK can never be true */
1396 assert(!SvNOKp(sv));
1397 assert(!SvNOK(sv));
2b5060ae 1398 /* FALLTHROUGH */
bd81e77b
NC
1399 case SVt_PVIO:
1400 case SVt_PVFM:
bd81e77b
NC
1401 case SVt_PVGV:
1402 case SVt_PVCV:
1403 case SVt_PVLV:
d361b004 1404 case SVt_INVLIST:
12c45b25 1405 case SVt_REGEXP:
bd81e77b
NC
1406 case SVt_PVMG:
1407 case SVt_PVNV:
1408 case SVt_PV:
93e68bfb 1409
d2a0f284 1410 assert(new_type_details->body_size);
bd81e77b
NC
1411 /* We always allocated the full length item with PURIFY. To do this
1412 we fake things so that arena is false for all 16 types.. */
1413 if(new_type_details->arena) {
1414 /* This points to the start of the allocated area. */
d2a0f284
JC
1415 new_body_inline(new_body, new_type);
1416 Zero(new_body, new_type_details->body_size, char);
bd81e77b
NC
1417 new_body = ((char *)new_body) - new_type_details->offset;
1418 } else {
1419 new_body = new_NOARENAZ(new_type_details);
1420 }
1421 SvANY(sv) = new_body;
5e2fc214 1422
bd81e77b 1423 if (old_type_details->copy) {
f9ba3d20
NC
1424 /* There is now the potential for an upgrade from something without
1425 an offset (PVNV or PVMG) to something with one (PVCV, PVFM) */
1426 int offset = old_type_details->offset;
1427 int length = old_type_details->copy;
1428
1429 if (new_type_details->offset > old_type_details->offset) {
d4c19fe8 1430 const int difference
f9ba3d20
NC
1431 = new_type_details->offset - old_type_details->offset;
1432 offset += difference;
1433 length -= difference;
1434 }
1435 assert (length >= 0);
1436
1437 Copy((char *)old_body + offset, (char *)new_body + offset, length,
1438 char);
bd81e77b
NC
1439 }
1440
1441#ifndef NV_ZERO_IS_ALLBITS_ZERO
f2524eef 1442 /* If NV 0.0 is stores as all bits 0 then Zero() already creates a
e5ce394c
NC
1443 * correct 0.0 for us. Otherwise, if the old body didn't have an
1444 * NV slot, but the new one does, then we need to initialise the
1445 * freshly created NV slot with whatever the correct bit pattern is
1446 * for 0.0 */
e22a937e
NC
1447 if (old_type_details->zero_nv && !new_type_details->zero_nv
1448 && !isGV_with_GP(sv))
bd81e77b 1449 SvNV_set(sv, 0);
82048762 1450#endif
5e2fc214 1451
2439e033 1452 if (UNLIKELY(new_type == SVt_PVIO)) {
85dca89a 1453 IO * const io = MUTABLE_IO(sv);
d963bf01 1454 GV *iogv = gv_fetchpvs("IO::File::", GV_ADD, SVt_PVHV);
85dca89a
NC
1455
1456 SvOBJECT_on(io);
1457 /* Clear the stashcache because a new IO could overrule a package
1458 name */
103f5a36 1459 DEBUG_o(Perl_deb(aTHX_ "sv_upgrade clearing PL_stashcache\n"));
85dca89a
NC
1460 hv_clear(PL_stashcache);
1461
85dca89a 1462 SvSTASH_set(io, MUTABLE_HV(SvREFCNT_inc(GvHV(iogv))));
f2524eef 1463 IoPAGE_LEN(sv) = 60;
85dca89a 1464 }
df6b4bd5 1465 if (old_type < SVt_PV) {
ed7df46e 1466 /* referent will be NULL unless the old type was SVt_IV emulating
4df7f6af 1467 SVt_RV */
ed7df46e 1468 sv->sv_u.svu_rv = referent;
4df7f6af 1469 }
bd81e77b
NC
1470 break;
1471 default:
afd78fd5
JH
1472 Perl_croak(aTHX_ "panic: sv_upgrade to unknown type %lu",
1473 (unsigned long)new_type);
bd81e77b 1474 }
73171d91 1475
5b306eef
DD
1476 /* if this is zero, this is a body-less SVt_NULL, SVt_IV/SVt_RV,
1477 and sometimes SVt_NV */
1478 if (old_type_details->body_size) {
bd81e77b 1479#ifdef PURIFY
beeec492 1480 safefree(old_body);
bd81e77b 1481#else
bc786448
GG
1482 /* Note that there is an assumption that all bodies of types that
1483 can be upgraded came from arenas. Only the more complex non-
1484 upgradable types are allowed to be directly malloc()ed. */
1485 assert(old_type_details->arena);
bd81e77b
NC
1486 del_body((void*)((char*)old_body + old_type_details->offset),
1487 &PL_body_roots[old_type]);
1488#endif
1489 }
1490}
73171d91 1491
bd81e77b
NC
1492/*
1493=for apidoc sv_backoff
73171d91 1494
fde67290 1495Remove any string offset. You should normally use the C<SvOOK_off> macro
bd81e77b 1496wrapper instead.
73171d91 1497
bd81e77b 1498=cut
73171d91
NC
1499*/
1500
fa7a1e49
DD
1501/* prior to 5.000 stable, this function returned the new OOK-less SvFLAGS
1502 prior to 5.23.4 this function always returned 0
1503*/
1504
1505void
ddeaf645 1506Perl_sv_backoff(SV *const sv)
bd81e77b 1507{
69240efd 1508 STRLEN delta;
7a4bba22 1509 const char * const s = SvPVX_const(sv);
7918f24d
NC
1510
1511 PERL_ARGS_ASSERT_SV_BACKOFF;
7918f24d 1512
bd81e77b
NC
1513 assert(SvOOK(sv));
1514 assert(SvTYPE(sv) != SVt_PVHV);
1515 assert(SvTYPE(sv) != SVt_PVAV);
7a4bba22 1516
69240efd
NC
1517 SvOOK_offset(sv, delta);
1518
7a4bba22
NC
1519 SvLEN_set(sv, SvLEN(sv) + delta);
1520 SvPV_set(sv, SvPVX(sv) - delta);
bd81e77b 1521 SvFLAGS(sv) &= ~SVf_OOK;
fa7a1e49
DD
1522 Move(s, SvPVX(sv), SvCUR(sv)+1, char);
1523 return;
bd81e77b 1524}
73171d91 1525
03885497
DM
1526
1527/* forward declaration */
1528static void S_sv_uncow(pTHX_ SV * const sv, const U32 flags);
1529
1530
bd81e77b
NC
1531/*
1532=for apidoc sv_grow
73171d91 1533
bd81e77b
NC
1534Expands the character buffer in the SV. If necessary, uses C<sv_unref> and
1535upgrades the SV to C<SVt_PV>. Returns a pointer to the character buffer.
1536Use the C<SvGROW> wrapper instead.
93e68bfb 1537
bd81e77b
NC
1538=cut
1539*/
93e68bfb 1540
e0060e30 1541
bd81e77b 1542char *
5aaab254 1543Perl_sv_grow(pTHX_ SV *const sv, STRLEN newlen)
bd81e77b 1544{
eb578fdb 1545 char *s;
93e68bfb 1546
7918f24d
NC
1547 PERL_ARGS_ASSERT_SV_GROW;
1548
bd81e77b
NC
1549 if (SvROK(sv))
1550 sv_unref(sv);
1551 if (SvTYPE(sv) < SVt_PV) {
1552 sv_upgrade(sv, SVt_PV);
1553 s = SvPVX_mutable(sv);
1554 }
1555 else if (SvOOK(sv)) { /* pv is offset? */
1556 sv_backoff(sv);
1557 s = SvPVX_mutable(sv);
1558 if (newlen > SvLEN(sv))
1559 newlen += 10 * (newlen - SvCUR(sv)); /* avoid copy each time */
bd81e77b
NC
1560 }
1561 else
db2c6cb3 1562 {
e0060e30 1563 if (SvIsCOW(sv)) S_sv_uncow(aTHX_ sv, 0);
bd81e77b 1564 s = SvPVX_mutable(sv);
db2c6cb3 1565 }
aeb18a1e 1566
93c10d60 1567#ifdef PERL_COPY_ON_WRITE
cbcb2a16 1568 /* the new COW scheme uses SvPVX(sv)[SvLEN(sv)-1] (if spare)
3c239bea 1569 * to store the COW count. So in general, allocate one more byte than
cbcb2a16
DM
1570 * asked for, to make it likely this byte is always spare: and thus
1571 * make more strings COW-able.
fe546b38 1572 *
fa8f4f85
TC
1573 * Only increment if the allocation isn't MEM_SIZE_MAX,
1574 * otherwise it will wrap to 0.
1575 */
fe546b38 1576 if ( newlen != MEM_SIZE_MAX )
cbcb2a16
DM
1577 newlen++;
1578#endif
1579
ce861ea7
YO
1580#if defined(PERL_USE_MALLOC_SIZE) && defined(Perl_safesysmalloc_size)
1581#define PERL_UNWARANTED_CHUMMINESS_WITH_MALLOC
1582#endif
1583
bd81e77b 1584 if (newlen > SvLEN(sv)) { /* need more room? */
f1200559 1585 STRLEN minlen = SvCUR(sv);
3c239bea 1586 minlen += (minlen >> PERL_STRLEN_EXPAND_SHIFT) + 10;
f1200559
WH
1587 if (newlen < minlen)
1588 newlen = minlen;
ce861ea7 1589#ifndef PERL_UNWARANTED_CHUMMINESS_WITH_MALLOC
7c641603
KW
1590
1591 /* Don't round up on the first allocation, as odds are pretty good that
1592 * the initial request is accurate as to what is really needed */
ce861ea7 1593 if (SvLEN(sv)) {
9efda33a
TC
1594 STRLEN rounded = PERL_STRLEN_ROUNDUP(newlen);
1595 if (rounded > newlen)
1596 newlen = rounded;
ce861ea7 1597 }
bd81e77b 1598#endif
98653f18 1599 if (SvLEN(sv) && s) {
10edeb5d 1600 s = (char*)saferealloc(s, newlen);
bd81e77b
NC
1601 }
1602 else {
10edeb5d 1603 s = (char*)safemalloc(newlen);
bd81e77b 1604 if (SvPVX_const(sv) && SvCUR(sv)) {
0a5fcc38 1605 Move(SvPVX_const(sv), s, SvCUR(sv), char);
bd81e77b
NC
1606 }
1607 }
1608 SvPV_set(sv, s);
ce861ea7 1609#ifdef PERL_UNWARANTED_CHUMMINESS_WITH_MALLOC
98653f18
NC
1610 /* Do this here, do it once, do it right, and then we will never get
1611 called back into sv_grow() unless there really is some growing
1612 needed. */
ca7c1a29 1613 SvLEN_set(sv, Perl_safesysmalloc_size(s));
98653f18 1614#else
bd81e77b 1615 SvLEN_set(sv, newlen);
98653f18 1616#endif
bd81e77b
NC
1617 }
1618 return s;
1619}
aeb18a1e 1620
bd81e77b
NC
1621/*
1622=for apidoc sv_setiv
932e9ff9 1623
bd81e77b 1624Copies an integer into the given SV, upgrading first if necessary.
fbe13c60 1625Does not handle 'set' magic. See also C<L</sv_setiv_mg>>.
463ee0b2 1626
bd81e77b
NC
1627=cut
1628*/
463ee0b2 1629
bd81e77b 1630void
5aaab254 1631Perl_sv_setiv(pTHX_ SV *const sv, const IV i)
bd81e77b 1632{
7918f24d
NC
1633 PERL_ARGS_ASSERT_SV_SETIV;
1634
bd81e77b
NC
1635 SV_CHECK_THINKFIRST_COW_DROP(sv);
1636 switch (SvTYPE(sv)) {
1637 case SVt_NULL:
bd81e77b 1638 case SVt_NV:
3376de98 1639 sv_upgrade(sv, SVt_IV);
bd81e77b 1640 break;
bd81e77b
NC
1641 case SVt_PV:
1642 sv_upgrade(sv, SVt_PVIV);
1643 break;
463ee0b2 1644
bd81e77b 1645 case SVt_PVGV:
6e592b3a
BM
1646 if (!isGV_with_GP(sv))
1647 break;
bd81e77b
NC
1648 case SVt_PVAV:
1649 case SVt_PVHV:
1650 case SVt_PVCV:
1651 case SVt_PVFM:
1652 case SVt_PVIO:
22e74366 1653 /* diag_listed_as: Can't coerce %s to %s in %s */
bd81e77b
NC
1654 Perl_croak(aTHX_ "Can't coerce %s to integer in %s", sv_reftype(sv,0),
1655 OP_DESC(PL_op));
c9a0dcdc 1656 NOT_REACHED; /* NOTREACHED */
0103ca14 1657 break;
42d0e0b7 1658 default: NOOP;
bd81e77b
NC
1659 }
1660 (void)SvIOK_only(sv); /* validate number */
1661 SvIV_set(sv, i);
1662 SvTAINT(sv);
1663}
932e9ff9 1664
bd81e77b
NC
1665/*
1666=for apidoc sv_setiv_mg
d33b2eba 1667
bd81e77b 1668Like C<sv_setiv>, but also handles 'set' magic.
1c846c1f 1669
bd81e77b
NC
1670=cut
1671*/
d33b2eba 1672
bd81e77b 1673void
5aaab254 1674Perl_sv_setiv_mg(pTHX_ SV *const sv, const IV i)
bd81e77b 1675{
7918f24d
NC
1676 PERL_ARGS_ASSERT_SV_SETIV_MG;
1677
bd81e77b
NC
1678 sv_setiv(sv,i);
1679 SvSETMAGIC(sv);
1680}
727879eb 1681
bd81e77b
NC
1682/*
1683=for apidoc sv_setuv
d33b2eba 1684
bd81e77b 1685Copies an unsigned integer into the given SV, upgrading first if necessary.
fbe13c60 1686Does not handle 'set' magic. See also C<L</sv_setuv_mg>>.
9b94d1dd 1687
bd81e77b
NC
1688=cut
1689*/
d33b2eba 1690
bd81e77b 1691void
5aaab254 1692Perl_sv_setuv(pTHX_ SV *const sv, const UV u)
bd81e77b 1693{
7918f24d
NC
1694 PERL_ARGS_ASSERT_SV_SETUV;
1695
013abb9b
NC
1696 /* With the if statement to ensure that integers are stored as IVs whenever
1697 possible:
bd81e77b 1698 u=1.49 s=0.52 cu=72.49 cs=10.64 scripts=270 tests=20865
d33b2eba 1699
bd81e77b
NC
1700 without
1701 u=1.35 s=0.47 cu=73.45 cs=11.43 scripts=270 tests=20865
1c846c1f 1702
013abb9b
NC
1703 If you wish to remove the following if statement, so that this routine
1704 (and its callers) always return UVs, please benchmark to see what the
1705 effect is. Modern CPUs may be different. Or may not :-)
bd81e77b
NC
1706 */
1707 if (u <= (UV)IV_MAX) {
1708 sv_setiv(sv, (IV)u);
1709 return;
1710 }
1711 sv_setiv(sv, 0);
1712 SvIsUV_on(sv);
1713 SvUV_set(sv, u);
1714}
d33b2eba 1715
bd81e77b
NC
1716/*
1717=for apidoc sv_setuv_mg
727879eb 1718
bd81e77b 1719Like C<sv_setuv>, but also handles 'set' magic.
9b94d1dd 1720
bd81e77b
NC
1721=cut
1722*/
5e2fc214 1723
bd81e77b 1724void
5aaab254 1725Perl_sv_setuv_mg(pTHX_ SV *const sv, const UV u)
bd81e77b 1726{
7918f24d
NC
1727 PERL_ARGS_ASSERT_SV_SETUV_MG;
1728
bd81e77b
NC
1729 sv_setuv(sv,u);
1730 SvSETMAGIC(sv);
1731}
5e2fc214 1732
954c1994 1733/*
bd81e77b 1734=for apidoc sv_setnv
954c1994 1735
bd81e77b 1736Copies a double into the given SV, upgrading first if necessary.
fbe13c60 1737Does not handle 'set' magic. See also C<L</sv_setnv_mg>>.
954c1994
GS
1738
1739=cut
1740*/
1741
63f97190 1742void
5aaab254 1743Perl_sv_setnv(pTHX_ SV *const sv, const NV num)
79072805 1744{
7918f24d
NC
1745 PERL_ARGS_ASSERT_SV_SETNV;
1746
bd81e77b
NC
1747 SV_CHECK_THINKFIRST_COW_DROP(sv);
1748 switch (SvTYPE(sv)) {
79072805 1749 case SVt_NULL:
79072805 1750 case SVt_IV:
bd81e77b 1751 sv_upgrade(sv, SVt_NV);
79072805
LW
1752 break;
1753 case SVt_PV:
79072805 1754 case SVt_PVIV:
bd81e77b 1755 sv_upgrade(sv, SVt_PVNV);
79072805 1756 break;
bd4b1eb5 1757
bd4b1eb5 1758 case SVt_PVGV:
6e592b3a
BM
1759 if (!isGV_with_GP(sv))
1760 break;
bd81e77b
NC
1761 case SVt_PVAV:
1762 case SVt_PVHV:
79072805 1763 case SVt_PVCV:
bd81e77b
NC
1764 case SVt_PVFM:
1765 case SVt_PVIO:
22e74366 1766 /* diag_listed_as: Can't coerce %s to %s in %s */
bd81e77b 1767 Perl_croak(aTHX_ "Can't coerce %s to number in %s", sv_reftype(sv,0),
94bbb3f4 1768 OP_DESC(PL_op));
c9a0dcdc 1769 NOT_REACHED; /* NOTREACHED */
0103ca14 1770 break;
42d0e0b7 1771 default: NOOP;
2068cd4d 1772 }
bd81e77b
NC
1773 SvNV_set(sv, num);
1774 (void)SvNOK_only(sv); /* validate number */
1775 SvTAINT(sv);
79072805
LW
1776}
1777
645c22ef 1778/*
bd81e77b 1779=for apidoc sv_setnv_mg
645c22ef 1780
bd81e77b 1781Like C<sv_setnv>, but also handles 'set' magic.
645c22ef
DM
1782
1783=cut
1784*/
1785
bd81e77b 1786void
5aaab254 1787Perl_sv_setnv_mg(pTHX_ SV *const sv, const NV num)
79072805 1788{
7918f24d
NC
1789 PERL_ARGS_ASSERT_SV_SETNV_MG;
1790
bd81e77b
NC
1791 sv_setnv(sv,num);
1792 SvSETMAGIC(sv);
79072805
LW
1793}
1794
3f7602fa
TC
1795/* Return a cleaned-up, printable version of sv, for non-numeric, or
1796 * not incrementable warning display.
1797 * Originally part of S_not_a_number().
1798 * The return value may be != tmpbuf.
bd81e77b 1799 */
954c1994 1800
3f7602fa
TC
1801STATIC const char *
1802S_sv_display(pTHX_ SV *const sv, char *tmpbuf, STRLEN tmpbuf_size) {
1803 const char *pv;
94463019 1804
3f7602fa 1805 PERL_ARGS_ASSERT_SV_DISPLAY;
7918f24d 1806
94463019 1807 if (DO_UTF8(sv)) {
3f7602fa 1808 SV *dsv = newSVpvs_flags("", SVs_TEMP);
37b8cdd1 1809 pv = sv_uni_display(dsv, sv, 32, UNI_DISPLAY_ISPRINT);
94463019
JH
1810 } else {
1811 char *d = tmpbuf;
3f7602fa 1812 const char * const limit = tmpbuf + tmpbuf_size - 8;
94463019
JH
1813 /* each *s can expand to 4 chars + "...\0",
1814 i.e. need room for 8 chars */
ecdeb87c 1815
00b6aa41
AL
1816 const char *s = SvPVX_const(sv);
1817 const char * const end = s + SvCUR(sv);
1818 for ( ; s < end && d < limit; s++ ) {
94463019 1819 int ch = *s & 0xFF;
bd27cf70 1820 if (! isASCII(ch) && !isPRINT_LC(ch)) {
94463019
JH
1821 *d++ = 'M';
1822 *d++ = '-';
bd27cf70
KW
1823
1824 /* Map to ASCII "equivalent" of Latin1 */
1825 ch = LATIN1_TO_NATIVE(NATIVE_TO_LATIN1(ch) & 127);
94463019
JH
1826 }
1827 if (ch == '\n') {
1828 *d++ = '\\';
1829 *d++ = 'n';
1830 }
1831 else if (ch == '\r') {
1832 *d++ = '\\';
1833 *d++ = 'r';
1834 }
1835 else if (ch == '\f') {
1836 *d++ = '\\';
1837 *d++ = 'f';
1838 }
1839 else if (ch == '\\') {
1840 *d++ = '\\';
1841 *d++ = '\\';
1842 }
1843 else if (ch == '\0') {
1844 *d++ = '\\';
1845 *d++ = '0';
1846 }
1847 else if (isPRINT_LC(ch))
1848 *d++ = ch;
1849 else {
1850 *d++ = '^';
1851 *d++ = toCTRL(ch);
1852 }
1853 }
1854 if (s < end) {
1855 *d++ = '.';
1856 *d++ = '.';
1857 *d++ = '.';
1858 }
1859 *d = '\0';
1860 pv = tmpbuf;
a0d0e21e 1861 }
a0d0e21e 1862
3f7602fa
TC
1863 return pv;
1864}
1865
1866/* Print an "isn't numeric" warning, using a cleaned-up,
1867 * printable version of the offending string
1868 */
1869
1870STATIC void
1871S_not_a_number(pTHX_ SV *const sv)
1872{
3f7602fa
TC
1873 char tmpbuf[64];
1874 const char *pv;
1875
1876 PERL_ARGS_ASSERT_NOT_A_NUMBER;
1877
1878 pv = sv_display(sv, tmpbuf, sizeof(tmpbuf));
1879
533c011a 1880 if (PL_op)
9014280d 1881 Perl_warner(aTHX_ packWARN(WARN_NUMERIC),
734856a2 1882 /* diag_listed_as: Argument "%s" isn't numeric%s */
94463019
JH
1883 "Argument \"%s\" isn't numeric in %s", pv,
1884 OP_DESC(PL_op));
a0d0e21e 1885 else
9014280d 1886 Perl_warner(aTHX_ packWARN(WARN_NUMERIC),
734856a2 1887 /* diag_listed_as: Argument "%s" isn't numeric%s */
94463019 1888 "Argument \"%s\" isn't numeric", pv);
a0d0e21e
LW
1889}
1890
3f7602fa
TC
1891STATIC void
1892S_not_incrementable(pTHX_ SV *const sv) {
3f7602fa
TC
1893 char tmpbuf[64];
1894 const char *pv;
1895
1896 PERL_ARGS_ASSERT_NOT_INCREMENTABLE;
1897
1898 pv = sv_display(sv, tmpbuf, sizeof(tmpbuf));
1899
1900 Perl_warner(aTHX_ packWARN(WARN_NUMERIC),
1901 "Argument \"%s\" treated as 0 in increment (++)", pv);
1902}
1903
c2988b20
NC
1904/*
1905=for apidoc looks_like_number
1906
645c22ef
DM
1907Test if the content of an SV looks like a number (or is a number).
1908C<Inf> and C<Infinity> are treated as numbers (so will not issue a
796b6530 1909non-numeric warning), even if your C<atof()> doesn't grok them. Get-magic is
f52e41ad 1910ignored.
c2988b20
NC
1911
1912=cut
1913*/
1914
1915I32
aad570aa 1916Perl_looks_like_number(pTHX_ SV *const sv)
c2988b20 1917{
eb578fdb 1918 const char *sbegin;
c2988b20 1919 STRLEN len;
ea2485eb 1920 int numtype;
c2988b20 1921
7918f24d
NC
1922 PERL_ARGS_ASSERT_LOOKS_LIKE_NUMBER;
1923
f52e41ad
FC
1924 if (SvPOK(sv) || SvPOKp(sv)) {
1925 sbegin = SvPV_nomg_const(sv, len);
c2988b20 1926 }
c2988b20 1927 else
e0ab1c0e 1928 return SvFLAGS(sv) & (SVf_NOK|SVp_NOK|SVf_IOK|SVp_IOK);
ea2485eb
JH
1929 numtype = grok_number(sbegin, len, NULL);
1930 return ((numtype & IS_NUMBER_TRAILING)) ? 0 : numtype;
c2988b20 1931}
25da4f38 1932
19f6321d
NC
1933STATIC bool
1934S_glob_2number(pTHX_ GV * const gv)
180488f8 1935{
7918f24d
NC
1936 PERL_ARGS_ASSERT_GLOB_2NUMBER;
1937
675c862f
AL
1938 /* We know that all GVs stringify to something that is not-a-number,
1939 so no need to test that. */
1940 if (ckWARN(WARN_NUMERIC))
8e629ff4
FC
1941 {
1942 SV *const buffer = sv_newmortal();
1943 gv_efullname3(buffer, gv, "*");
675c862f 1944 not_a_number(buffer);
8e629ff4 1945 }
675c862f
AL
1946 /* We just want something true to return, so that S_sv_2iuv_common
1947 can tail call us and return true. */
19f6321d 1948 return TRUE;
675c862f
AL
1949}
1950
25da4f38
IZ
1951/* Actually, ISO C leaves conversion of UV to IV undefined, but
1952 until proven guilty, assume that things are not that bad... */
1953
645c22ef
DM
1954/*
1955 NV_PRESERVES_UV:
1956
1957 As 64 bit platforms often have an NV that doesn't preserve all bits of
28e5dec8
JH
1958 an IV (an assumption perl has been based on to date) it becomes necessary
1959 to remove the assumption that the NV always carries enough precision to
1960 recreate the IV whenever needed, and that the NV is the canonical form.
1961 Instead, IV/UV and NV need to be given equal rights. So as to not lose
645c22ef 1962 precision as a side effect of conversion (which would lead to insanity
28e5dec8 1963 and the dragon(s) in t/op/numconvert.t getting very angry) the intent is
8a4a3196
KW
1964 1) to distinguish between IV/UV/NV slots that have a valid conversion cached
1965 where precision was lost, and IV/UV/NV slots that have a valid conversion
1966 which has lost no precision
645c22ef 1967 2) to ensure that if a numeric conversion to one form is requested that
28e5dec8
JH
1968 would lose precision, the precise conversion (or differently
1969 imprecise conversion) is also performed and cached, to prevent
1970 requests for different numeric formats on the same SV causing
1971 lossy conversion chains. (lossless conversion chains are perfectly
1972 acceptable (still))
1973
1974
1975 flags are used:
1976 SvIOKp is true if the IV slot contains a valid value
1977 SvIOK is true only if the IV value is accurate (UV if SvIOK_UV true)
1978 SvNOKp is true if the NV slot contains a valid value
1979 SvNOK is true only if the NV value is accurate
1980
1981 so
645c22ef 1982 while converting from PV to NV, check to see if converting that NV to an
28e5dec8
JH
1983 IV(or UV) would lose accuracy over a direct conversion from PV to
1984 IV(or UV). If it would, cache both conversions, return NV, but mark
1985 SV as IOK NOKp (ie not NOK).
1986
645c22ef 1987 While converting from PV to IV, check to see if converting that IV to an
28e5dec8
JH
1988 NV would lose accuracy over a direct conversion from PV to NV. If it
1989 would, cache both conversions, flag similarly.
1990
1991 Before, the SV value "3.2" could become NV=3.2 IV=3 NOK, IOK quite
1992 correctly because if IV & NV were set NV *always* overruled.
645c22ef
DM
1993 Now, "3.2" will become NV=3.2 IV=3 NOK, IOKp, because the flag's meaning
1994 changes - now IV and NV together means that the two are interchangeable:
28e5dec8 1995 SvIVX == (IV) SvNVX && SvNVX == (NV) SvIVX;
d460ef45 1996
645c22ef
DM
1997 The benefit of this is that operations such as pp_add know that if
1998 SvIOK is true for both left and right operands, then integer addition
1999 can be used instead of floating point (for cases where the result won't
2000 overflow). Before, floating point was always used, which could lead to
28e5dec8
JH
2001 loss of precision compared with integer addition.
2002
2003 * making IV and NV equal status should make maths accurate on 64 bit
2004 platforms
2005 * may speed up maths somewhat if pp_add and friends start to use
645c22ef 2006 integers when possible instead of fp. (Hopefully the overhead in
28e5dec8
JH
2007 looking for SvIOK and checking for overflow will not outweigh the
2008 fp to integer speedup)
2009 * will slow down integer operations (callers of SvIV) on "inaccurate"
2010 values, as the change from SvIOK to SvIOKp will cause a call into
2011 sv_2iv each time rather than a macro access direct to the IV slot
2012 * should speed up number->string conversion on integers as IV is
645c22ef 2013 favoured when IV and NV are equally accurate
28e5dec8
JH
2014
2015 ####################################################################
645c22ef
DM
2016 You had better be using SvIOK_notUV if you want an IV for arithmetic:
2017 SvIOK is true if (IV or UV), so you might be getting (IV)SvUV.
2018 On the other hand, SvUOK is true iff UV.
28e5dec8
JH
2019 ####################################################################
2020
645c22ef 2021 Your mileage will vary depending your CPU's relative fp to integer
28e5dec8
JH
2022 performance ratio.
2023*/
2024
2025#ifndef NV_PRESERVES_UV
645c22ef
DM
2026# define IS_NUMBER_UNDERFLOW_IV 1
2027# define IS_NUMBER_UNDERFLOW_UV 2
2028# define IS_NUMBER_IV_AND_UV 2
2029# define IS_NUMBER_OVERFLOW_IV 4
2030# define IS_NUMBER_OVERFLOW_UV 5
2031
2032/* sv_2iuv_non_preserve(): private routine for use by sv_2iv() and sv_2uv() */
28e5dec8
JH
2033
2034/* For sv_2nv these three cases are "SvNOK and don't bother casting" */
2035STATIC int
5aaab254 2036S_sv_2iuv_non_preserve(pTHX_ SV *const sv
47031da6
NC
2037# ifdef DEBUGGING
2038 , I32 numtype
2039# endif
2040 )
28e5dec8 2041{
7918f24d 2042 PERL_ARGS_ASSERT_SV_2IUV_NON_PRESERVE;
23491f1d 2043 PERL_UNUSED_CONTEXT;
7918f24d 2044
147e3846 2045 DEBUG_c(PerlIO_printf(Perl_debug_log,"sv_2iuv_non '%s', IV=0x%" UVxf " NV=%" NVgf " inttype=%" UVXf "\n", SvPVX_const(sv), SvIVX(sv), SvNVX(sv), (UV)numtype));
28e5dec8
JH
2046 if (SvNVX(sv) < (NV)IV_MIN) {
2047 (void)SvIOKp_on(sv);
2048 (void)SvNOK_on(sv);
45977657 2049 SvIV_set(sv, IV_MIN);
28e5dec8
JH
2050 return IS_NUMBER_UNDERFLOW_IV;
2051 }
2052 if (SvNVX(sv) > (NV)UV_MAX) {
2053 (void)SvIOKp_on(sv);
2054 (void)SvNOK_on(sv);
2055 SvIsUV_on(sv);
607fa7f2 2056 SvUV_set(sv, UV_MAX);
28e5dec8
JH
2057 return IS_NUMBER_OVERFLOW_UV;
2058 }
c2988b20
NC
2059 (void)SvIOKp_on(sv);
2060 (void)SvNOK_on(sv);
2061 /* Can't use strtol etc to convert this string. (See truth table in
2062 sv_2iv */
2063 if (SvNVX(sv) <= (UV)IV_MAX) {
45977657 2064 SvIV_set(sv, I_V(SvNVX(sv)));
659c4b96 2065 if ((NV)(SvIVX(sv)) == SvNVX(sv)) {
c2988b20
NC
2066 SvIOK_on(sv); /* Integer is precise. NOK, IOK */
2067 } else {
2068 /* Integer is imprecise. NOK, IOKp */
2069 }
2070 return SvNVX(sv) < 0 ? IS_NUMBER_UNDERFLOW_UV : IS_NUMBER_IV_AND_UV;
2071 }
2072 SvIsUV_on(sv);
607fa7f2 2073 SvUV_set(sv, U_V(SvNVX(sv)));
659c4b96 2074 if ((NV)(SvUVX(sv)) == SvNVX(sv)) {
c2988b20
NC
2075 if (SvUVX(sv) == UV_MAX) {
2076 /* As we know that NVs don't preserve UVs, UV_MAX cannot
2077 possibly be preserved by NV. Hence, it must be overflow.
2078 NOK, IOKp */
2079 return IS_NUMBER_OVERFLOW_UV;
2080 }
2081 SvIOK_on(sv); /* Integer is precise. NOK, UOK */
2082 } else {
2083 /* Integer is imprecise. NOK, IOKp */
28e5dec8 2084 }
c2988b20 2085 return IS_NUMBER_OVERFLOW_IV;
28e5dec8 2086}
645c22ef
DM
2087#endif /* !NV_PRESERVES_UV*/
2088
a13f4dff 2089/* If numtype is infnan, set the NV of the sv accordingly.
5564cd7f 2090 * If numtype is anything else, try setting the NV using Atof(PV). */
3c81f0b3
DD
2091#ifdef USING_MSVC6
2092# pragma warning(push)
2093# pragma warning(disable:4756;disable:4056)
2094#endif
a13f4dff 2095static void
3823048b 2096S_sv_setnv(pTHX_ SV* sv, int numtype)
a13f4dff 2097{
07925c5e 2098 bool pok = cBOOL(SvPOK(sv));
5564cd7f 2099 bool nok = FALSE;
a7157111 2100#ifdef NV_INF
a13f4dff
JH
2101 if ((numtype & IS_NUMBER_INFINITY)) {
2102 SvNV_set(sv, (numtype & IS_NUMBER_NEG) ? -NV_INF : NV_INF);
5564cd7f 2103 nok = TRUE;
a7157111
JH
2104 } else
2105#endif
2106#ifdef NV_NAN
2107 if ((numtype & IS_NUMBER_NAN)) {
3823048b 2108 SvNV_set(sv, NV_NAN);
d48bd569 2109 nok = TRUE;
a7157111
JH
2110 } else
2111#endif
2112 if (pok) {
a13f4dff 2113 SvNV_set(sv, Atof(SvPVX_const(sv)));
d48bd569
JH
2114 /* Purposefully no true nok here, since we don't want to blow
2115 * away the possible IOK/UV of an existing sv. */
2116 }
5564cd7f 2117 if (nok) {
d48bd569 2118 SvNOK_only(sv); /* No IV or UV please, this is pure infnan. */
5564cd7f
JH
2119 if (pok)
2120 SvPOK_on(sv); /* PV is okay, though. */
2121 }
a13f4dff 2122}
3c81f0b3
DD
2123#ifdef USING_MSVC6
2124# pragma warning(pop)
2125#endif
a13f4dff 2126
af359546 2127STATIC bool
7918f24d
NC
2128S_sv_2iuv_common(pTHX_ SV *const sv)
2129{
7918f24d
NC
2130 PERL_ARGS_ASSERT_SV_2IUV_COMMON;
2131
af359546 2132 if (SvNOKp(sv)) {
28e5dec8
JH
2133 /* erm. not sure. *should* never get NOKp (without NOK) from sv_2nv
2134 * without also getting a cached IV/UV from it at the same time
2135 * (ie PV->NV conversion should detect loss of accuracy and cache
af359546
NC
2136 * IV or UV at same time to avoid this. */
2137 /* IV-over-UV optimisation - choose to cache IV if possible */
25da4f38
IZ
2138
2139 if (SvTYPE(sv) == SVt_NV)
2140 sv_upgrade(sv, SVt_PVNV);
2141
28e5dec8
JH
2142 (void)SvIOKp_on(sv); /* Must do this first, to clear any SvOOK */
2143 /* < not <= as for NV doesn't preserve UV, ((NV)IV_MAX+1) will almost
2144 certainly cast into the IV range at IV_MAX, whereas the correct
2145 answer is the UV IV_MAX +1. Hence < ensures that dodgy boundary
2146 cases go to UV */
e91de695
JH
2147#if defined(NAN_COMPARE_BROKEN) && defined(Perl_isnan)
2148 if (Perl_isnan(SvNVX(sv))) {
2149 SvUV_set(sv, 0);
2150 SvIsUV_on(sv);
2151 return FALSE;
2152 }
2153#endif
28e5dec8 2154 if (SvNVX(sv) < (NV)IV_MAX + 0.5) {
45977657 2155 SvIV_set(sv, I_V(SvNVX(sv)));
659c4b96 2156 if (SvNVX(sv) == (NV) SvIVX(sv)
28e5dec8 2157#ifndef NV_PRESERVES_UV
53e2bfb7 2158 && SvIVX(sv) != IV_MIN /* avoid negating IV_MIN below */
28e5dec8
JH
2159 && (((UV)1 << NV_PRESERVES_UV_BITS) >
2160 (UV)(SvIVX(sv) > 0 ? SvIVX(sv) : -SvIVX(sv)))
2161 /* Don't flag it as "accurately an integer" if the number
2162 came from a (by definition imprecise) NV operation, and
2163 we're outside the range of NV integer precision */
2164#endif
2165 ) {
a43d94f2
NC
2166 if (SvNOK(sv))
2167 SvIOK_on(sv); /* Can this go wrong with rounding? NWC */
2168 else {
2169 /* scalar has trailing garbage, eg "42a" */
2170 }
28e5dec8 2171 DEBUG_c(PerlIO_printf(Perl_debug_log,
147e3846 2172 "0x%" UVxf " iv(%" NVgf " => %" IVdf ") (precise)\n",
28e5dec8
JH
2173 PTR2UV(sv),
2174 SvNVX(sv),
2175 SvIVX(sv)));
2176
2177 } else {
2178 /* IV not precise. No need to convert from PV, as NV
2179 conversion would already have cached IV if it detected
2180 that PV->IV would be better than PV->NV->IV
2181 flags already correct - don't set public IOK. */
2182 DEBUG_c(PerlIO_printf(Perl_debug_log,
147e3846 2183 "0x%" UVxf " iv(%" NVgf " => %" IVdf ") (imprecise)\n",
28e5dec8
JH
2184 PTR2UV(sv),
2185 SvNVX(sv),
2186 SvIVX(sv)));
2187 }
2188 /* Can the above go wrong if SvIVX == IV_MIN and SvNVX < IV_MIN,
2189 but the cast (NV)IV_MIN rounds to a the value less (more
2190 negative) than IV_MIN which happens to be equal to SvNVX ??
2191 Analogous to 0xFFFFFFFFFFFFFFFF rounding up to NV (2**64) and
2192 NV rounding back to 0xFFFFFFFFFFFFFFFF, so UVX == UV(NVX) and
2193 (NV)UVX == NVX are both true, but the values differ. :-(
2194 Hopefully for 2s complement IV_MIN is something like
2195 0x8000000000000000 which will be exact. NWC */
d460ef45 2196 }
25da4f38 2197 else {
607fa7f2 2198 SvUV_set(sv, U_V(SvNVX(sv)));
28e5dec8 2199 if (
659c4b96 2200 (SvNVX(sv) == (NV) SvUVX(sv))
28e5dec8
JH
2201#ifndef NV_PRESERVES_UV
2202 /* Make sure it's not 0xFFFFFFFFFFFFFFFF */
2203 /*&& (SvUVX(sv) != UV_MAX) irrelevant with code below */
2204 && (((UV)1 << NV_PRESERVES_UV_BITS) > SvUVX(sv))
2205 /* Don't flag it as "accurately an integer" if the number
2206 came from a (by definition imprecise) NV operation, and
2207 we're outside the range of NV integer precision */
2208#endif
a43d94f2 2209 && SvNOK(sv)
28e5dec8
JH
2210 )
2211 SvIOK_on(sv);
25da4f38 2212 SvIsUV_on(sv);
1c846c1f 2213 DEBUG_c(PerlIO_printf(Perl_debug_log,
147e3846 2214 "0x%" UVxf " 2iv(%" UVuf " => %" IVdf ") (as unsigned)\n",
56431972 2215 PTR2UV(sv),
57def98f
JH
2216 SvUVX(sv),
2217 SvUVX(sv)));
25da4f38 2218 }
748a9306 2219 }
cd84013a 2220 else if (SvPOKp(sv)) {
c2988b20 2221 UV value;
80e5abf2
DM
2222 int numtype;
2223 const char *s = SvPVX_const(sv);
2224 const STRLEN cur = SvCUR(sv);
2225
2226 /* short-cut for a single digit string like "1" */
2227
2228 if (cur == 1) {
2229 char c = *s;
2230 if (isDIGIT(c)) {
2231 if (SvTYPE(sv) < SVt_PVIV)
2232 sv_upgrade(sv, SVt_PVIV);
2233 (void)SvIOK_on(sv);
2234 SvIV_set(sv, (IV)(c - '0'));
2235 return FALSE;
2236 }
2237 }
2238
2239 numtype = grok_number(s, cur, &value);
af359546 2240 /* We want to avoid a possible problem when we cache an IV/ a UV which
25da4f38 2241 may be later translated to an NV, and the resulting NV is not
c2988b20
NC
2242 the same as the direct translation of the initial string
2243 (eg 123.456 can shortcut to the IV 123 with atol(), but we must
2244 be careful to ensure that the value with the .456 is around if the
2245 NV value is requested in the future).
1c846c1f 2246
af359546 2247 This means that if we cache such an IV/a UV, we need to cache the
25da4f38 2248 NV as well. Moreover, we trade speed for space, and do not
28e5dec8 2249 cache the NV if we are sure it's not needed.
25da4f38 2250 */
16b7a9a4 2251
c2988b20
NC
2252 /* SVt_PVNV is one higher than SVt_PVIV, hence this order */
2253 if ((numtype & (IS_NUMBER_IN_UV | IS_NUMBER_NOT_INT))
2254 == IS_NUMBER_IN_UV) {
5e045b90 2255 /* It's definitely an integer, only upgrade to PVIV */
28e5dec8
JH
2256 if (SvTYPE(sv) < SVt_PVIV)
2257 sv_upgrade(sv, SVt_PVIV);
f7bbb42a 2258 (void)SvIOK_on(sv);
c2988b20
NC
2259 } else if (SvTYPE(sv) < SVt_PVNV)
2260 sv_upgrade(sv, SVt_PVNV);
28e5dec8 2261
a13f4dff 2262 if ((numtype & (IS_NUMBER_INFINITY | IS_NUMBER_NAN))) {
75a57a38 2263 if (ckWARN(WARN_NUMERIC) && ((numtype & IS_NUMBER_TRAILING)))
6b322424 2264 not_a_number(sv);
3823048b 2265 S_sv_setnv(aTHX_ sv, numtype);
a13f4dff
JH
2266 return FALSE;
2267 }
2268
f2524eef 2269 /* If NVs preserve UVs then we only use the UV value if we know that
c2988b20
NC
2270 we aren't going to call atof() below. If NVs don't preserve UVs
2271 then the value returned may have more precision than atof() will
2272 return, even though value isn't perfectly accurate. */
2273 if ((numtype & (IS_NUMBER_IN_UV
2274#ifdef NV_PRESERVES_UV
2275 | IS_NUMBER_NOT_INT
2276#endif
2277 )) == IS_NUMBER_IN_UV) {
2278 /* This won't turn off the public IOK flag if it was set above */
2279 (void)SvIOKp_on(sv);
2280
2281 if (!(numtype & IS_NUMBER_NEG)) {
2282 /* positive */;
2283 if (value <= (UV)IV_MAX) {
45977657 2284 SvIV_set(sv, (IV)value);
c2988b20 2285 } else {
af359546 2286 /* it didn't overflow, and it was positive. */
607fa7f2 2287 SvUV_set(sv, value);
c2988b20
NC
2288 SvIsUV_on(sv);
2289 }
2290 } else {
2291 /* 2s complement assumption */
2292 if (value <= (UV)IV_MIN) {
53e2bfb7
DM
2293 SvIV_set(sv, value == (UV)IV_MIN
2294 ? IV_MIN : -(IV)value);
c2988b20
NC
2295 } else {
2296 /* Too negative for an IV. This is a double upgrade, but
d1be9408 2297 I'm assuming it will be rare. */
c2988b20
NC
2298 if (SvTYPE(sv) < SVt_PVNV)
2299 sv_upgrade(sv, SVt_PVNV);
2300 SvNOK_on(sv);
2301 SvIOK_off(sv);
2302 SvIOKp_on(sv);
9d6ce603 2303 SvNV_set(sv, -(NV)value);
45977657 2304 SvIV_set(sv, IV_MIN);
c2988b20
NC
2305 }
2306 }
2307 }
2308 /* For !NV_PRESERVES_UV and IS_NUMBER_IN_UV and IS_NUMBER_NOT_INT we
2309 will be in the previous block to set the IV slot, and the next
2310 block to set the NV slot. So no else here. */
2311
2312 if ((numtype & (IS_NUMBER_IN_UV | IS_NUMBER_NOT_INT))
2313 != IS_NUMBER_IN_UV) {
2314 /* It wasn't an (integer that doesn't overflow the UV). */
3823048b 2315 S_sv_setnv(aTHX_ sv, numtype);
28e5dec8 2316
c2988b20
NC
2317 if (! numtype && ckWARN(WARN_NUMERIC))
2318 not_a_number(sv);
28e5dec8 2319
147e3846 2320 DEBUG_c(PerlIO_printf(Perl_debug_log, "0x%" UVxf " 2iv(%" NVgf ")\n",
c2988b20 2321 PTR2UV(sv), SvNVX(sv)));
28e5dec8 2322
28e5dec8 2323#ifdef NV_PRESERVES_UV
af359546
NC
2324 (void)SvIOKp_on(sv);
2325 (void)SvNOK_on(sv);
e91de695
JH
2326#if defined(NAN_COMPARE_BROKEN) && defined(Perl_isnan)
2327 if (Perl_isnan(SvNVX(sv))) {
2328 SvUV_set(sv, 0);
2329 SvIsUV_on(sv);
2330 return FALSE;
2331 }
2332#endif
af359546
NC
2333 if (SvNVX(sv) < (NV)IV_MAX + 0.5) {
2334 SvIV_set(sv, I_V(SvNVX(sv)));
2335 if ((NV)(SvIVX(sv)) == SvNVX(sv)) {
2336 SvIOK_on(sv);
2337 } else {
6f207bd3 2338 NOOP; /* Integer is imprecise. NOK, IOKp */
af359546
NC
2339 }
2340 /* UV will not work better than IV */
2341 } else {
2342 if (SvNVX(sv) > (NV)UV_MAX) {
2343 SvIsUV_on(sv);
2344 /* Integer is inaccurate. NOK, IOKp, is UV */
2345 SvUV_set(sv, UV_MAX);
af359546
NC
2346 } else {
2347 SvUV_set(sv, U_V(SvNVX(sv)));
2348 /* 0xFFFFFFFFFFFFFFFF not an issue in here, NVs
2349 NV preservse UV so can do correct comparison. */
2350 if ((NV)(SvUVX(sv)) == SvNVX(sv)) {
2351 SvIOK_on(sv);
af359546 2352 } else {
6f207bd3 2353 NOOP; /* Integer is imprecise. NOK, IOKp, is UV */
af359546
NC
2354 }
2355 }
4b0c9573 2356 SvIsUV_on(sv);
af359546 2357 }
28e5dec8 2358#else /* NV_PRESERVES_UV */
c2988b20
NC
2359 if ((numtype & (IS_NUMBER_IN_UV | IS_NUMBER_NOT_INT))
2360 == (IS_NUMBER_IN_UV | IS_NUMBER_NOT_INT)) {
af359546 2361 /* The IV/UV slot will have been set from value returned by
c2988b20
NC
2362 grok_number above. The NV slot has just been set using
2363 Atof. */
560b0c46 2364 SvNOK_on(sv);
c2988b20
NC
2365 assert (SvIOKp(sv));
2366 } else {
2367 if (((UV)1 << NV_PRESERVES_UV_BITS) >
2368 U_V(SvNVX(sv) > 0 ? SvNVX(sv) : -SvNVX(sv))) {
2369 /* Small enough to preserve all bits. */
2370 (void)SvIOKp_on(sv);
2371 SvNOK_on(sv);
45977657 2372 SvIV_set(sv, I_V(SvNVX(sv)));
659c4b96 2373 if ((NV)(SvIVX(sv)) == SvNVX(sv))
c2988b20
NC
2374 SvIOK_on(sv);
2375 /* Assumption: first non-preserved integer is < IV_MAX,
2376 this NV is in the preserved range, therefore: */
2377 if (!(U_V(SvNVX(sv) > 0 ? SvNVX(sv) : -SvNVX(sv))
2378 < (UV)IV_MAX)) {
147e3846 2379 Perl_croak(aTHX_ "sv_2iv assumed (U_V(fabs((double)SvNVX(sv))) < (UV)IV_MAX) but SvNVX(sv)=%" NVgf " U_V is 0x%" UVxf ", IV_MAX is 0x%" UVxf "\n", SvNVX(sv), U_V(SvNVX(sv)), (UV)IV_MAX);
c2988b20
NC
2380 }
2381 } else {
2382 /* IN_UV NOT_INT
2383 0 0 already failed to read UV.
2384 0 1 already failed to read UV.
2385 1 0 you won't get here in this case. IV/UV
2386 slot set, public IOK, Atof() unneeded.
2387 1 1 already read UV.
2388 so there's no point in sv_2iuv_non_preserve() attempting
2389 to use atol, strtol, strtoul etc. */
47031da6 2390# ifdef DEBUGGING
40a17c4c 2391 sv_2iuv_non_preserve (sv, numtype);
47031da6
NC
2392# else
2393 sv_2iuv_non_preserve (sv);
2394# endif
c2988b20
NC
2395 }
2396 }
28e5dec8 2397#endif /* NV_PRESERVES_UV */
a43d94f2
NC
2398 /* It might be more code efficient to go through the entire logic above
2399 and conditionally set with SvIOKp_on() rather than SvIOK(), but it
2400 gets complex and potentially buggy, so more programmer efficient
2401 to do it this way, by turning off the public flags: */
2402 if (!numtype)
2403 SvFLAGS(sv) &= ~(SVf_IOK|SVf_NOK);
25da4f38 2404 }
af359546
NC
2405 }
2406 else {
675c862f 2407 if (isGV_with_GP(sv))
159b6efe 2408 return glob_2number(MUTABLE_GV(sv));
180488f8 2409
4f62cd62 2410 if (!PL_localizing && ckWARN(WARN_UNINITIALIZED))
af359546 2411 report_uninit(sv);
25da4f38
IZ
2412 if (SvTYPE(sv) < SVt_IV)
2413 /* Typically the caller expects that sv_any is not NULL now. */
2414 sv_upgrade(sv, SVt_IV);
af359546
NC
2415 /* Return 0 from the caller. */
2416 return TRUE;
2417 }
2418 return FALSE;
2419}
2420
2421/*
2422=for apidoc sv_2iv_flags
2423
2424Return the integer value of an SV, doing any necessary string
c5608a1f 2425conversion. If C<flags> has the C<SV_GMAGIC> bit set, does an C<mg_get()> first.
af359546
NC
2426Normally used via the C<SvIV(sv)> and C<SvIVx(sv)> macros.
2427
2428=cut
2429*/
2430
2431IV
5aaab254 2432Perl_sv_2iv_flags(pTHX_ SV *const sv, const I32 flags)
af359546 2433{
1061065f 2434 PERL_ARGS_ASSERT_SV_2IV_FLAGS;
4bac9ae4 2435
217f6fa3
FC
2436 assert (SvTYPE(sv) != SVt_PVAV && SvTYPE(sv) != SVt_PVHV
2437 && SvTYPE(sv) != SVt_PVFM);
2438
4bac9ae4
CS
2439 if (SvGMAGICAL(sv) && (flags & SV_GMAGIC))
2440 mg_get(sv);
2441
2442 if (SvROK(sv)) {
2443 if (SvAMAGIC(sv)) {
2444 SV * tmpstr;
2445 if (flags & SV_SKIP_OVERLOAD)
2446 return 0;
2447 tmpstr = AMG_CALLunary(sv, numer_amg);
2448 if (tmpstr && (!SvROK(tmpstr) || (SvRV(tmpstr) != SvRV(sv)))) {
2449 return SvIV(tmpstr);
2450 }
2451 }
2452 return PTR2IV(SvRV(sv));
2453 }
2454
8d919b0a 2455 if (SvVALID(sv) || isREGEXP(sv)) {
4e8879f3
DM
2456 /* FBMs use the space for SvIVX and SvNVX for other purposes, so
2457 must not let them cache IVs.
2b2b6d6d
NC
2458 In practice they are extremely unlikely to actually get anywhere
2459 accessible by user Perl code - the only way that I'm aware of is when
2460 a constant subroutine which is used as the second argument to index.
cd84013a
FC
2461
2462 Regexps have no SvIVX and SvNVX fields.
2b2b6d6d 2463 */
df6b4bd5 2464 assert(SvPOKp(sv));
e20b6c3b 2465 {
71c558c3 2466 UV value;
8d919b0a
FC
2467 const char * const ptr =
2468 isREGEXP(sv) ? RX_WRAPPED((REGEXP*)sv) : SvPVX_const(sv);
e91de695
JH
2469 const int numtype
2470 = grok_number(ptr, SvCUR(sv), &value);
71c558c3
NC
2471
2472 if ((numtype & (IS_NUMBER_IN_UV | IS_NUMBER_NOT_INT))
2473 == IS_NUMBER_IN_UV) {
2474 /* It's definitely an integer */
2475 if (numtype & IS_NUMBER_NEG) {
2476 if (value < (UV)IV_MIN)
2477 return -(IV)value;
2478 } else {
2479 if (value < (UV)IV_MAX)
2480 return (IV)value;
2481 }
2482 }
058b8ae2 2483
e91de695
JH
2484 /* Quite wrong but no good choices. */
2485 if ((numtype & IS_NUMBER_INFINITY)) {
2486 return (numtype & IS_NUMBER_NEG) ? IV_MIN : IV_MAX;
2487 } else if ((numtype & IS_NUMBER_NAN)) {
2488 return 0; /* So wrong. */
2489 }
2490
71c558c3
NC
2491 if (!numtype) {
2492 if (ckWARN(WARN_NUMERIC))
2493 not_a_number(sv);
2494 }
8d919b0a 2495 return I_V(Atof(ptr));
e20b6c3b 2496 }
4bac9ae4
CS
2497 }
2498
2499 if (SvTHINKFIRST(sv)) {
af359546
NC
2500 if (SvREADONLY(sv) && !SvOK(sv)) {
2501 if (ckWARN(WARN_UNINITIALIZED))
2502 report_uninit(sv);
2503 return 0;
2504 }
2505 }
4bac9ae4 2506
af359546
NC
2507 if (!SvIOKp(sv)) {
2508 if (S_sv_2iuv_common(aTHX_ sv))
2509 return 0;
79072805 2510 }
4bac9ae4 2511
147e3846 2512 DEBUG_c(PerlIO_printf(Perl_debug_log, "0x%" UVxf " 2iv(%" IVdf ")\n",
1d7c1841 2513 PTR2UV(sv),SvIVX(sv)));
25da4f38 2514 return SvIsUV(sv) ? (IV)SvUVX(sv) : SvIVX(sv);
79072805
LW
2515}
2516
645c22ef 2517/*
891f9566 2518=for apidoc sv_2uv_flags
645c22ef
DM
2519
2520Return the unsigned integer value of an SV, doing any necessary string
c5608a1f 2521conversion. If C<flags> has the C<SV_GMAGIC> bit set, does an C<mg_get()> first.
891f9566 2522Normally used via the C<SvUV(sv)> and C<SvUVx(sv)> macros.
645c22ef
DM
2523
2524=cut
2525*/
2526
ff68c719 2527UV
5aaab254 2528Perl_sv_2uv_flags(pTHX_ SV *const sv, const I32 flags)
ff68c719 2529{
1061065f 2530 PERL_ARGS_ASSERT_SV_2UV_FLAGS;
4bac9ae4
CS
2531
2532 if (SvGMAGICAL(sv) && (flags & SV_GMAGIC))
2533 mg_get(sv);
2534
2535 if (SvROK(sv)) {
2536 if (SvAMAGIC(sv)) {
2537 SV *tmpstr;
2538 if (flags & SV_SKIP_OVERLOAD)
2539 return 0;
2540 tmpstr = AMG_CALLunary(sv, numer_amg);
2541 if (tmpstr && (!SvROK(tmpstr) || (SvRV(tmpstr) != SvRV(sv)))) {
2542 return SvUV(tmpstr);
2543 }
2544 }
2545 return PTR2UV(SvRV(sv));
2546 }
2547
8d919b0a 2548 if (SvVALID(sv) || isREGEXP(sv)) {
2b2b6d6d 2549 /* FBMs use the space for SvIVX and SvNVX for other purposes, and use
cd84013a
FC
2550 the same flag bit as SVf_IVisUV, so must not let them cache IVs.
2551 Regexps have no SvIVX and SvNVX fields. */
df6b4bd5 2552 assert(SvPOKp(sv));
e20b6c3b 2553 {
71c558c3 2554 UV value;
8d919b0a
FC
2555 const char * const ptr =
2556 isREGEXP(sv) ? RX_WRAPPED((REGEXP*)sv) : SvPVX_const(sv);
e91de695
JH
2557 const int numtype
2558 = grok_number(ptr, SvCUR(sv), &value);
71c558c3
NC
2559
2560 if ((numtype & (IS_NUMBER_IN_UV | IS_NUMBER_NOT_INT))
2561 == IS_NUMBER_IN_UV) {
2562 /* It's definitely an integer */
2563 if (!(numtype & IS_NUMBER_NEG))
2564 return value;
2565 }
058b8ae2 2566
e91de695
JH
2567 /* Quite wrong but no good choices. */
2568 if ((numtype & IS_NUMBER_INFINITY)) {
2569 return UV_MAX; /* So wrong. */
2570 } else if ((numtype & IS_NUMBER_NAN)) {
2571 return 0; /* So wrong. */
2572 }
2573
71c558c3
NC
2574 if (!numtype) {
2575 if (ckWARN(WARN_NUMERIC))
2576 not_a_number(sv);
2577 }
8d919b0a 2578 return U_V(Atof(ptr));
e20b6c3b 2579 }
4bac9ae4
CS
2580 }
2581
2582 if (SvTHINKFIRST(sv)) {
0336b60e 2583 if (SvREADONLY(sv) && !SvOK(sv)) {
0336b60e 2584 if (ckWARN(WARN_UNINITIALIZED))
29489e7c 2585 report_uninit(sv);
ff68c719
PP
2586 return 0;
2587 }
2588 }
4bac9ae4 2589
af359546
NC
2590 if (!SvIOKp(sv)) {
2591 if (S_sv_2iuv_common(aTHX_ sv))
2592 return 0;
ff68c719 2593 }
25da4f38 2594
147e3846 2595 DEBUG_c(PerlIO_printf(Perl_debug_log, "0x%" UVxf " 2uv(%" UVuf ")\n",
1d7c1841 2596 PTR2UV(sv),SvUVX(sv)));
25da4f38 2597 return SvIsUV(sv) ? SvUVX(sv) : (UV)SvIVX(sv);
ff68c719
PP
2598}
2599
645c22ef 2600/*
196007d1 2601=for apidoc sv_2nv_flags
645c22ef
DM
2602
2603Return the num value of an SV, doing any necessary string or integer
c5608a1f 2604conversion. If C<flags> has the C<SV_GMAGIC> bit set, does an C<mg_get()> first.
39d5de13 2605Normally used via the C<SvNV(sv)> and C<SvNVx(sv)> macros.
645c22ef
DM
2606
2607=cut
2608*/
2609
65202027 2610NV
5aaab254 2611Perl_sv_2nv_flags(pTHX_ SV *const sv, const I32 flags)
79072805 2612{
1061065f
DD
2613 PERL_ARGS_ASSERT_SV_2NV_FLAGS;
2614
217f6fa3
FC
2615 assert (SvTYPE(sv) != SVt_PVAV && SvTYPE(sv) != SVt_PVHV
2616 && SvTYPE(sv) != SVt_PVFM);
8d919b0a 2617 if (SvGMAGICAL(sv) || SvVALID(sv) || isREGEXP(sv)) {
2b2b6d6d 2618 /* FBMs use the space for SvIVX and SvNVX for other purposes, and use
cd84013a
FC
2619 the same flag bit as SVf_IVisUV, so must not let them cache NVs.
2620 Regexps have no SvIVX and SvNVX fields. */
8d919b0a 2621 const char *ptr;
39d5de13
DM
2622 if (flags & SV_GMAGIC)
2623 mg_get(sv);
463ee0b2
LW
2624 if (SvNOKp(sv))
2625 return SvNVX(sv);
cd84013a 2626 if (SvPOKp(sv) && !SvIOKp(sv)) {
8d919b0a 2627 ptr = SvPVX_const(sv);
041457d9 2628 if (!SvIOKp(sv) && ckWARN(WARN_NUMERIC) &&
8d919b0a 2629 !grok_number(ptr, SvCUR(sv), NULL))
a0d0e21e 2630 not_a_number(sv);
8d919b0a 2631 return Atof(ptr);
a0d0e21e 2632 }
25da4f38 2633 if (SvIOKp(sv)) {
1c846c1f 2634 if (SvIsUV(sv))
65202027 2635 return (NV)SvUVX(sv);
25da4f38 2636 else
65202027 2637 return (NV)SvIVX(sv);
47a72cb8
NC
2638 }
2639 if (SvROK(sv)) {
2640 goto return_rok;
2641 }
2642 assert(SvTYPE(sv) >= SVt_PVMG);
2643 /* This falls through to the report_uninit near the end of the
2644 function. */
2645 } else if (SvTHINKFIRST(sv)) {
a0d0e21e 2646 if (SvROK(sv)) {
47a72cb8 2647 return_rok:
deb46114 2648 if (SvAMAGIC(sv)) {
aee036bb
DM
2649 SV *tmpstr;
2650 if (flags & SV_SKIP_OVERLOAD)
2651 return 0;
31d632c3 2652 tmpstr = AMG_CALLunary(sv, numer_amg);
deb46114
NC
2653 if (tmpstr && (!SvROK(tmpstr) || (SvRV(tmpstr) != SvRV(sv)))) {
2654 return SvNV(tmpstr);
2655 }
2656 }
2657 return PTR2NV(SvRV(sv));
a0d0e21e 2658 }
0336b60e 2659 if (SvREADONLY(sv) && !SvOK(sv)) {
599cee73 2660 if (ckWARN(WARN_UNINITIALIZED))
29489e7c 2661 report_uninit(sv);
ed6116ce
LW
2662 return 0.0;
2663 }
79072805
LW
2664 }
2665 if (SvTYPE(sv) < SVt_NV) {
7e25a7e9
NC
2666 /* The logic to use SVt_PVNV if necessary is in sv_upgrade. */
2667 sv_upgrade(sv, SVt_NV);
097ee67d 2668 DEBUG_c({
f93f4e46 2669 STORE_NUMERIC_LOCAL_SET_STANDARD();
1d7c1841 2670 PerlIO_printf(Perl_debug_log,
147e3846 2671 "0x%" UVxf " num(%" NVgf ")\n",
1d7c1841 2672 PTR2UV(sv), SvNVX(sv));
097ee67d
JH
2673 RESTORE_NUMERIC_LOCAL();
2674 });
79072805
LW
2675 }
2676 else if (SvTYPE(sv) < SVt_PVNV)
2677 sv_upgrade(sv, SVt_PVNV);
59d8ce62
NC
2678 if (SvNOKp(sv)) {
2679 return SvNVX(sv);
61604483 2680 }
59d8ce62 2681 if (SvIOKp(sv)) {
9d6ce603 2682 SvNV_set(sv, SvIsUV(sv) ? (NV)SvUVX(sv) : (NV)SvIVX(sv));
28e5dec8 2683#ifdef NV_PRESERVES_UV
a43d94f2
NC
2684 if (SvIOK(sv))
2685 SvNOK_on(sv);
2686 else
2687 SvNOKp_on(sv);
28e5dec8
JH
2688#else
2689 /* Only set the public NV OK flag if this NV preserves the IV */
2690 /* Check it's not 0xFFFFFFFFFFFFFFFF */
a43d94f2
NC
2691 if (SvIOK(sv) &&
2692 SvIsUV(sv) ? ((SvUVX(sv) != UV_MAX)&&(SvUVX(sv) == U_V(SvNVX(sv))))
28e5dec8
JH
2693 : (SvIVX(sv) == I_V(SvNVX(sv))))
2694 SvNOK_on(sv);
2695 else
2696 SvNOKp_on(sv);
2697#endif
93a17b20 2698 }
cd84013a 2699 else if (SvPOKp(sv)) {
c2988b20 2700 UV value;
3823048b 2701 const int numtype = grok_number(SvPVX_const(sv), SvCUR(sv), &value);
041457d9 2702 if (!SvIOKp(sv) && !numtype && ckWARN(WARN_NUMERIC))
a0d0e21e 2703 not_a_number(sv);
28e5dec8 2704#ifdef NV_PRESERVES_UV
c2988b20
NC
2705 if ((numtype & (IS_NUMBER_IN_UV | IS_NUMBER_NOT_INT))
2706 == IS_NUMBER_IN_UV) {
5e045b90 2707 /* It's definitely an integer */
9d6ce603 2708 SvNV_set(sv, (numtype & IS_NUMBER_NEG) ? -(NV)value : (NV)value);
66d83377 2709 } else {
3823048b 2710 S_sv_setnv(aTHX_ sv, numtype);
66d83377 2711 }
a43d94f2
NC
2712 if (numtype)
2713 SvNOK_on(sv);
2714 else
2715 SvNOKp_on(sv);
28e5dec8 2716#else
e91de695
JH
2717 SvNV_set(sv, Atof(SvPVX_const(sv)));
2718 /* Only set the public NV OK flag if this NV preserves the value in
2719 the PV at least as well as an IV/UV would.
2720 Not sure how to do this 100% reliably. */
2721 /* if that shift count is out of range then Configure's test is
2722 wonky. We shouldn't be in here with NV_PRESERVES_UV_BITS ==
2723 UV_BITS */
2724 if (((UV)1 << NV_PRESERVES_UV_BITS) >
2725 U_V(SvNVX(sv) > 0 ? SvNVX(sv) : -SvNVX(sv))) {
2726 SvNOK_on(sv); /* Definitely small enough to preserve all bits */
2727 } else if (!(numtype & IS_NUMBER_IN_UV)) {
2728 /* Can't use strtol etc to convert this string, so don't try.
2729 sv_2iv and sv_2uv will use the NV to convert, not the PV. */
c2988b20
NC
2730 SvNOK_on(sv);
2731 } else {
e91de695 2732 /* value has been set. It may not be precise. */
53e2bfb7 2733 if ((numtype & IS_NUMBER_NEG) && (value >= (UV)IV_MIN)) {
e91de695
JH
2734 /* 2s complement assumption for (UV)IV_MIN */
2735 SvNOK_on(sv); /* Integer is too negative. */
c2988b20 2736 } else {
e91de695
JH
2737 SvNOKp_on(sv);
2738 SvIOKp_on(sv);
6fa402ec 2739
e91de695 2740 if (numtype & IS_NUMBER_NEG) {
02b08bbc
DM
2741 /* -IV_MIN is undefined, but we should never reach
2742 * this point with both IS_NUMBER_NEG and value ==
2743 * (UV)IV_MIN */
2744 assert(value != (UV)IV_MIN);
e91de695
JH
2745 SvIV_set(sv, -(IV)value);
2746 } else if (value <= (UV)IV_MAX) {
2747 SvIV_set(sv, (IV)value);
2748 } else {
2749 SvUV_set(sv, value);
2750 SvIsUV_on(sv);
2751 }
c2988b20 2752
e91de695
JH
2753 if (numtype & IS_NUMBER_NOT_INT) {
2754 /* I believe that even if the original PV had decimals,
2755 they are lost beyond the limit of the FP precision.
2756 However, neither is canonical, so both only get p
2757 flags. NWC, 2000/11/25 */
2758 /* Both already have p flags, so do nothing */
2759 } else {
2760 const NV nv = SvNVX(sv);
2761 /* XXX should this spot have NAN_COMPARE_BROKEN, too? */
2762 if (SvNVX(sv) < (NV)IV_MAX + 0.5) {
2763 if (SvIVX(sv) == I_V(nv)) {
2764 SvNOK_on(sv);
2765 } else {
2766 /* It had no "." so it must be integer. */
2767 }
2768 SvIOK_on(sv);
0f83c5a4 2769 } else {
e91de695
JH
2770 /* between IV_MAX and NV(UV_MAX).
2771 Could be slightly > UV_MAX */
2772
2773 if (numtype & IS_NUMBER_NOT_INT) {
2774 /* UV and NV both imprecise. */
0f83c5a4 2775 } else {
e91de695
JH
2776 const UV nv_as_uv = U_V(nv);
2777
2778 if (value == nv_as_uv && SvUVX(sv) != UV_MAX) {
2779 SvNOK_on(sv);
c2988b20 2780 }
e91de695 2781 SvIOK_on(sv);
c2988b20
NC
2782 }
2783 }
2784 }
2785 }
0f83c5a4 2786 }
e91de695
JH
2787 /* It might be more code efficient to go through the entire logic above
2788 and conditionally set with SvNOKp_on() rather than SvNOK(), but it
2789 gets complex and potentially buggy, so more programmer efficient
2790 to do it this way, by turning off the public flags: */
2791 if (!numtype)
2792 SvFLAGS(sv) &= ~(SVf_IOK|SVf_NOK);
28e5dec8 2793#endif /* NV_PRESERVES_UV */
93a17b20 2794 }
79072805 2795 else {
e91de695
JH
2796 if (isGV_with_GP(sv)) {
2797 glob_2number(MUTABLE_GV(sv));
2798 return 0.0;
2799 }
180488f8 2800
e91de695
JH
2801 if (!PL_localizing && ckWARN(WARN_UNINITIALIZED))
2802 report_uninit(sv);
2803 assert (SvTYPE(sv) >= SVt_NV);
2804 /* Typically the caller expects that sv_any is not NULL now. */
2805 /* XXX Ilya implies that this is a bug in callers that assume this
2806 and ideally should be fixed. */
2807 return 0.0;
79072805 2808 }
097ee67d 2809 DEBUG_c({
e91de695 2810 STORE_NUMERIC_LOCAL_SET_STANDARD();
147e3846 2811 PerlIO_printf(Perl_debug_log, "0x%" UVxf " 2nv(%" NVgf ")\n",
e91de695
JH
2812 PTR2UV(sv), SvNVX(sv));
2813 RESTORE_NUMERIC_LOCAL();
2814 });
463ee0b2 2815 return SvNVX(sv);
79072805
LW
2816}
2817
800401ee
JH
2818/*
2819=for apidoc sv_2num
2820
2821Return an SV with the numeric value of the source SV, doing any necessary
d024d1a7
FC
2822reference or overload conversion. The caller is expected to have handled
2823get-magic already.
800401ee
JH
2824
2825=cut
2826*/
2827
2828SV *
5aaab254 2829Perl_sv_2num(pTHX_ SV *const sv)
800401ee 2830{
7918f24d
NC
2831 PERL_ARGS_ASSERT_SV_2NUM;
2832
b9ee0594
RGS
2833 if (!SvROK(sv))
2834 return sv;
800401ee 2835 if (SvAMAGIC(sv)) {
31d632c3 2836 SV * const tmpsv = AMG_CALLunary(sv, numer_amg);
a02ec77a 2837 TAINT_IF(tmpsv && SvTAINTED(tmpsv));
800401ee
JH
2838 if (tmpsv && (!SvROK(tmpsv) || (SvRV(tmpsv) != SvRV(sv))))
2839 return sv_2num(tmpsv);
2840 }
2841 return sv_2mortal(newSVuv(PTR2UV(SvRV(sv))));
2842}
2843
645c22ef
DM
2844/* uiv_2buf(): private routine for use by sv_2pv_flags(): print an IV or
2845 * UV as a string towards the end of buf, and return pointers to start and
2846 * end of it.
2847 *
2848 * We assume that buf is at least TYPE_CHARS(UV) long.
2849 */
2850
864dbfa3 2851static char *
5de3775c 2852S_uiv_2buf(char *const buf, const IV iv, UV uv, const int is_uv, char **const peob)
25da4f38 2853{
25da4f38 2854 char *ptr = buf + TYPE_CHARS(UV);
823a54a3 2855 char * const ebuf = ptr;
25da4f38 2856 int sign;
25da4f38 2857
7918f24d
NC
2858 PERL_ARGS_ASSERT_UIV_2BUF;
2859
25da4f38
IZ
2860 if (is_uv)
2861 sign = 0;
2862 else if (iv >= 0) {
2863 uv = iv;
2864 sign = 0;
2865 } else {
53e2bfb7 2866 uv = (iv == IV_MIN) ? (UV)iv : (UV)(-iv);
25da4f38
IZ
2867 sign = 1;
2868 }
2869 do {
eb160463 2870 *--ptr = '0' + (char)(uv % 10);
25da4f38
IZ
2871 } while (uv /= 10);
2872 if (sign)
2873 *--ptr = '-';
2874 *peob = ebuf;
2875 return ptr;
2876}
2877
bfaa02d5
JH
2878/* Helper for sv_2pv_flags and sv_vcatpvfn_flags. If the NV is an
2879 * infinity or a not-a-number, writes the appropriate strings to the
2880 * buffer, including a zero byte. On success returns the written length,
3bde2d43
JH
2881 * excluding the zero byte, on failure (not an infinity, not a nan)
2882 * returns zero, assert-fails on maxlen being too short.
3823048b
JH
2883 *
2884 * XXX for "Inf", "-Inf", and "NaN", we could have three read-only
2885 * shared string constants we point to, instead of generating a new
2886 * string for each instance. */
bfaa02d5 2887STATIC size_t
3823048b 2888S_infnan_2pv(NV nv, char* buffer, size_t maxlen, char plus) {
3bde2d43 2889 char* s = buffer;
bfaa02d5 2890 assert(maxlen >= 4);
3bde2d43
JH
2891 if (Perl_isinf(nv)) {
2892 if (nv < 0) {
2893 if (maxlen < 5) /* "-Inf\0" */
2894 return 0;
2895 *s++ = '-';
2896 } else if (plus) {
2897 *s++ = '+';
6e915616 2898 }
3bde2d43
JH
2899 *s++ = 'I';
2900 *s++ = 'n';
2901 *s++ = 'f';
2902 }
2903 else if (Perl_isnan(nv)) {
2904 *s++ = 'N';
2905 *s++ = 'a';
2906 *s++ = 'N';
2907 /* XXX optionally output the payload mantissa bits as
2908 * "(unsigned)" (to match the nan("...") C99 function,
2909 * or maybe as "(0xhhh...)" would make more sense...
2910 * provide a format string so that the user can decide?
2911 * NOTE: would affect the maxlen and assert() logic.*/
2912 }
2913 else {
2914 return 0;
bfaa02d5 2915 }
3bde2d43 2916 assert((s == buffer + 3) || (s == buffer + 4));
defe49c8
AL
2917 *s = 0;
2918 return s - buffer;
bfaa02d5
JH
2919}
2920
2921/*
2922=for apidoc sv_2pv_flags
2923
796b6530 2924Returns a pointer to the string value of an SV, and sets C<*lp> to its length.
c5608a1f 2925If flags has the C<SV_GMAGIC> bit set, does an C<mg_get()> first. Coerces C<sv> to a
bfaa02d5
JH
2926string if necessary. Normally invoked via the C<SvPV_flags> macro.
2927C<sv_2pv()> and C<sv_2pv_nomg> usually end up here too.
2928
2929=cut
2930*/
2931
2932char *
2933Perl_sv_2pv_flags(pTHX_ SV *const sv, STRLEN *const lp, const I32 flags)
2934{
2935 char *s;
2936
2937 PERL_ARGS_ASSERT_SV_2PV_FLAGS;
2938
2939 assert (SvTYPE(sv) != SVt_PVAV && SvTYPE(sv) != SVt_PVHV
2940 && SvTYPE(sv) != SVt_PVFM);
2941 if (SvGMAGICAL(sv) && (flags & SV_GMAGIC))
2942 mg_get(sv);
2943 if (SvROK(sv)) {
2944 if (SvAMAGIC(sv)) {
2945 SV *tmpstr;
2946 if (flags & SV_SKIP_OVERLOAD)
2947 return NULL;
2948 tmpstr = AMG_CALLunary(sv, string_amg);
2949 TAINT_IF(tmpstr && SvTAINTED(tmpstr));
2950 if (tmpstr && (!SvROK(tmpstr) || (SvRV(tmpstr) != SvRV(sv)))) {
2951 /* Unwrap this: */
2952 /* char *pv = lp ? SvPV(tmpstr, *lp) : SvPV_nolen(tmpstr);
2953 */
2954
2955 char *pv;
2956 if ((SvFLAGS(tmpstr) & (SVf_POK)) == SVf_POK) {
2957 if (flags & SV_CONST_RETURN) {
2958 pv = (char *) SvPVX_const(tmpstr);
2959 } else {
2960 pv = (flags & SV_MUTABLE_RETURN)
2961 ? SvPVX_mutable(tmpstr) : SvPVX(tmpstr);
2962 }
2963 if (lp)
2964 *lp = SvCUR(tmpstr);
2965 } else {
2966 pv = sv_2pv_flags(tmpstr, lp, flags);
2967 }
2968 if (SvUTF8(tmpstr))
2969 SvUTF8_on(sv);
2970 else
2971 SvUTF8_off(sv);
2972 return pv;
2973 }
2974 }
2975 {
2976 STRLEN len;
2977 char *retval;
2978 char *buffer;
2979 SV *const referent = SvRV(sv);
2980
2981 if (!referent) {
2982 len = 7;
2983 retval = buffer = savepvn("NULLREF", len);
2984 } else if (SvTYPE(referent) == SVt_REGEXP &&
2985 (!(PL_curcop->cop_hints & HINT_NO_AMAGIC) ||
2986 amagic_is_enabled(string_amg))) {
2987 REGEXP * const re = (REGEXP *)MUTABLE_PTR(referent);
2988
2989 assert(re);
2990
2991 /* If the regex is UTF-8 we want the containing scalar to
2992 have an UTF-8 flag too */
2993 if (RX_UTF8(re))
2994 SvUTF8_on(sv);
2995 else
2996 SvUTF8_off(sv);
2997
2998 if (lp)
2999 *lp = RX_WRAPLEN(re);
3000
3001 return RX_WRAPPED(re);
3002 } else {
3003 const char *const typestr = sv_reftype(referent, 0);
3004 const STRLEN typelen = strlen(typestr);
3005 UV addr = PTR2UV(referent);
3006 const char *stashname = NULL;
3007 STRLEN stashnamelen = 0; /* hush, gcc */
3008 const char *buffer_end;
3009
3010 if (SvOBJECT(referent)) {
3011 const HEK *const name = HvNAME_HEK(SvSTASH(referent));
3012
3013 if (name) {
3014 stashname = HEK_KEY(name);
3015 stashnamelen = HEK_LEN(name);
3016
3017 if (HEK_UTF8(name)) {
3018 SvUTF8_on(sv);
3019 } else {
3020 SvUTF8_off(sv);
3021 }
3022 } else {
3023 stashname = "__ANON__";
3024 stashnamelen = 8;
3025 }
3026 len = stashnamelen + 1 /* = */ + typelen + 3 /* (0x */
3027 + 2 * sizeof(UV) + 2 /* )\0 */;
3028 } else {
3029 len = typelen + 3 /* (0x */
3030 + 2 * sizeof(UV) + 2 /* )\0 */;
3031 }
fafee734 3032
4bac9ae4
CS
3033 Newx(buffer, len, char);
3034 buffer_end = retval = buffer + len;
3035
3036 /* Working backwards */
3037 *--retval = '\0';
3038 *--retval = ')';
3039 do {
3040 *--retval = PL_hexdigit[addr & 15];
3041 } while (addr >>= 4);
3042 *--retval = 'x';
3043 *--retval = '0';
3044 *--retval = '(';
3045
3046 retval -= typelen;
3047 memcpy(retval, typestr, typelen);
3048
3049 if (stashname) {
3050 *--retval = '=';
3051 retval -= stashnamelen;
3052 memcpy(retval, stashname, stashnamelen);
c080367d 3053 }
4bac9ae4
CS
3054 /* retval may not necessarily have reached the start of the
3055 buffer here. */
3056 assert (retval >= buffer);
3057
3058 len = buffer_end - retval - 1; /* -1 for that \0 */
463ee0b2 3059 }
cdb061a3 3060 if (lp)
4bac9ae4
CS
3061 *lp = len;
3062 SAVEFREEPV(buffer);
3063 return retval;
79072805 3064 }
79072805 3065 }
4bac9ae4
CS
3066
3067 if (SvPOKp(sv)) {
3068 if (lp)
3069 *lp = SvCUR(sv);
3070 if (flags & SV_MUTABLE_RETURN)
3071 return SvPVX_mutable(sv);
3072 if (flags & SV_CONST_RETURN)
3073 return (char *)SvPVX_const(sv);
3074 return SvPVX(sv);
3075 }
3076
3077 if (SvIOK(sv)) {
28e5dec8
JH
3078 /* I'm assuming that if both IV and NV are equally valid then
3079 converting the IV is going to be more efficient */
e1ec3a88 3080 const U32 isUIOK = SvIsUV(sv);
28e5dec8
JH
3081 char buf[TYPE_CHARS(UV)];
3082 char *ebuf, *ptr;
97a130b8 3083 STRLEN len;
28e5dec8
JH
3084
3085 if (SvTYPE(sv) < SVt_PVIV)
3086 sv_upgrade(sv, SVt_PVIV);
4ea1d550 3087 ptr = uiv_2buf(buf, SvIVX(sv), SvUVX(sv), isUIOK, &ebuf);
97a130b8 3088 len = ebuf - ptr;
5902b6a9 3089 /* inlined from sv_setpvn */
97a130b8
NC
3090 s = SvGROW_mutable(sv, len + 1);
3091 Move(ptr, s, len, char);
3092 s += len;
28e5dec8 3093 *s = '\0';
b127e37e 3094 SvPOK_on(sv);
28e5dec8 3095 }
4bac9ae4 3096 else if (SvNOK(sv)) {
79072805
LW
3097 if (SvTYPE(sv) < SVt_PVNV)
3098 sv_upgrade(sv, SVt_PVNV);
128eeacb
DD
3099 if (SvNVX(sv) == 0.0
3100#if defined(NAN_COMPARE_BROKEN) && defined(Perl_isnan)
3101 && !Perl_isnan(SvNVX(sv))
3102#endif
3103 ) {
29912d93
NC
3104 s = SvGROW_mutable(sv, 2);
3105 *s++ = '0';
3106 *s = '\0';
3107 } else {
5e85836e 3108 STRLEN len;
fb8cdbc5 3109 STRLEN size = 5; /* "-Inf\0" */
0c7e610f 3110
fb8cdbc5 3111 s = SvGROW_mutable(sv, size);
3823048b 3112 len = S_infnan_2pv(SvNVX(sv), s, size, 0);
fb8cdbc5 3113 if (len > 0) {
0c7e610f 3114 s += len;
fb8cdbc5
JH
3115 SvPOK_on(sv);
3116 }
0c7e610f 3117 else {
0c7e610f 3118 /* some Xenix systems wipe out errno here */
fb8cdbc5
JH
3119 dSAVE_ERRNO;
3120
3840bff0
JH
3121 size =
3122 1 + /* sign */
3123 1 + /* "." */
3124 NV_DIG +
3125 1 + /* "e" */
3126 1 + /* sign */
3127 5 + /* exponent digits */
3128 1 + /* \0 */
3129 2; /* paranoia */
b127e37e 3130
fb8cdbc5 3131 s = SvGROW_mutable(sv, size);
b127e37e 3132#ifndef USE_LOCALE_NUMERIC
a4eca1d4
JH
3133 SNPRINTF_G(SvNVX(sv), s, SvLEN(sv), NV_DIG);
3134
0c7e610f
JH
3135 SvPOK_on(sv);
3136#else
28acfe03 3137 {
3840bff0 3138 bool local_radix;
67d796ae
KW
3139 DECLARATION_FOR_LC_NUMERIC_MANIPULATION;
3140 STORE_LC_NUMERIC_SET_TO_NEEDED();
3840bff0 3141
3dbc6af5 3142 local_radix = PL_numeric_local && PL_numeric_radix_sv;
4c039fd8
DM
3143 if (local_radix && SvCUR(PL_numeric_radix_sv) > 1) {
3144 size += SvCUR(PL_numeric_radix_sv) - 1;
3840bff0
JH
3145 s = SvGROW_mutable(sv, size);
3146 }
3147
a4eca1d4 3148 SNPRINTF_G(SvNVX(sv), s, SvLEN(sv), NV_DIG);
0c7e610f
JH
3149
3150 /* If the radix character is UTF-8, and actually is in the
3151 * output, turn on the UTF-8 flag for the scalar */
3dbc6af5
KW
3152 if ( local_radix
3153 && SvUTF8(PL_numeric_radix_sv)
3154 && instr(s, SvPVX_const(PL_numeric_radix_sv)))
3155 {
3840bff0
JH
3156 SvUTF8_on(sv);
3157 }
3158
0c7e610f 3159 RESTORE_LC_NUMERIC();
28acfe03 3160 }
68e8f474 3161
0c7e610f
JH
3162 /* We don't call SvPOK_on(), because it may come to
3163 * pass that the locale changes so that the
3164 * stringification we just did is no longer correct. We
3165 * will have to re-stringify every time it is needed */
b127e37e 3166#endif
0c7e610f
JH
3167 RESTORE_ERRNO;
3168 }
3169 while (*s) s++;
bbce6d69 3170 }
79072805 3171 }
4bac9ae4
CS
3172 else if (isGV_with_GP(sv)) {
3173 GV *const gv = MUTABLE_GV(sv);
3174 SV *const buffer = sv_newmortal();
8d1c3e26 3175
4bac9ae4 3176 gv_efullname3(buffer, gv, "*");
180488f8 3177
4bac9ae4
CS
3178 assert(SvPOK(buffer));
3179 if (SvUTF8(buffer))
3180 SvUTF8_on(sv);
1097da16
TC
3181 else
3182 SvUTF8_off(sv);
4bac9ae4
CS
3183 if (lp)
3184 *lp = SvCUR(buffer);
3185 return SvPVX(buffer);
3186 }
3187 else {
cdb061a3 3188 if (lp)
00b6aa41 3189 *lp = 0;
9f621bb0
NC
3190 if (flags & SV_UNDEF_RETURNS_NULL)
3191 return NULL;
4f62cd62 3192 if (!PL_localizing && ckWARN(WARN_UNINITIALIZED))
9f621bb0 3193 report_uninit(sv);
4bac9ae4
CS
3194 /* Typically the caller expects that sv_any is not NULL now. */
3195 if (!SvREADONLY(sv) && SvTYPE(sv) < SVt_PV)
25da4f38 3196 sv_upgrade(sv, SVt_PV);
73d840c0 3197 return (char *)"";
79072805 3198 }
4bac9ae4 3199
cdb061a3 3200 {
823a54a3 3201 const STRLEN len = s - SvPVX_const(sv);
cdb061a3
NC
3202 if (lp)
3203 *lp = len;
3204 SvCUR_set(sv, len);
3205 }
147e3846 3206 DEBUG_c(PerlIO_printf(Perl_debug_log, "0x%" UVxf " 2pv(%s)\n",
3f7c398e 3207 PTR2UV(sv),SvPVX_const(sv)));
4d84ee25
NC
3208 if (flags & SV_CONST_RETURN)
3209 return (char *)SvPVX_const(sv);
10516c54
NC
3210 if (flags & SV_MUTABLE_RETURN)
3211 return SvPVX_mutable(sv);
463ee0b2
LW
3212 return SvPVX(sv);
3213}
3214
645c22ef 3215/*
6050d10e
JP
3216=for apidoc sv_copypv
3217
3218Copies a stringified representation of the source SV into the
796b6530 3219destination SV. Automatically performs any necessary C<mg_get> and
54f0641b 3220coercion of numeric values into strings. Guaranteed to preserve
796b6530
KW
3221C<UTF8> flag even from overloaded objects. Similar in nature to
3222C<sv_2pv[_flags]> but operates directly on an SV instead of just the
3223string. Mostly uses C<sv_2pv_flags> to do its work, except when that
6050d10e
JP
3224would lose the UTF-8'ness of the PV.
3225
4bac9ae4
CS
3226=for apidoc sv_copypv_nomg
3227
796b6530 3228Like C<sv_copypv>, but doesn't invoke get magic first.
4bac9ae4
CS
3229
3230=for apidoc sv_copypv_flags
3231
796b6530 3232Implementation of C<sv_copypv> and C<sv_copypv_nomg>. Calls get magic iff flags
c5608a1f 3233has the C<SV_GMAGIC> bit set.
4bac9ae4 3234
6050d10e
JP
3235=cut
3236*/
3237
3238void
5aaab254 3239Perl_sv_copypv_flags(pTHX_ SV *const dsv, SV *const ssv, const I32 flags)
4bac9ae4 3240{
446eaa42 3241 STRLEN len;
4bac9ae4 3242 const char *s;
7918f24d 3243
4bac9ae4 3244 PERL_ARGS_ASSERT_SV_COPYPV_FLAGS;
7918f24d 3245
c77ed9ca 3246 s = SvPV_flags_const(ssv,len,(flags & SV_GMAGIC));
cb50f42d 3247 sv_setpvn(dsv,s,len);
446eaa42 3248 if (SvUTF8(ssv))
cb50f42d 3249 SvUTF8_on(dsv);
446eaa42 3250 else
cb50f42d 3251 SvUTF8_off(dsv);
6050d10e
JP
3252}
3253
3254/*
645c22ef
DM
3255=for apidoc sv_2pvbyte
3256
796b6530 3257Return a pointer to the byte-encoded representation of the SV, and set C<*lp>
1e54db1a 3258to its length. May cause the SV to be downgraded from UTF-8 as a
645c22ef
DM
3259side-effect.
3260
3261Usually accessed via the C<SvPVbyte> macro.
3262
3263=cut
3264*/
3265
7340a771 3266char *
5aaab254 3267Perl_sv_2pvbyte(pTHX_ SV *sv, STRLEN *const lp)
7340a771 3268{
7918f24d
NC
3269 PERL_ARGS_ASSERT_SV_2PVBYTE;
3270
48120f8f 3271 SvGETMAGIC(sv);
4499db73
FC
3272 if (((SvREADONLY(sv) || SvFAKE(sv)) && !SvIsCOW(sv))
3273 || isGV_with_GP(sv) || SvROK(sv)) {
a901b181 3274 SV *sv2 = sv_newmortal();
48120f8f 3275 sv_copypv_nomg(sv2,sv);
a901b181
FC
3276 sv = sv2;
3277 }
0875d2fe 3278 sv_utf8_downgrade(sv,0);
71eb6d8c 3279 return lp ? SvPV_nomg(sv,*lp) : SvPV_nomg_nolen(sv);
7340a771
GS
3280}
3281
645c22ef 3282/*
035cbb0e
RGS
3283=for apidoc sv_2pvutf8
3284
796b6530 3285Return a pointer to the UTF-8-encoded representation of the SV, and set C<*lp>
035cbb0e
RGS
3286to its length. May cause the SV to be upgraded to UTF-8 as a side-effect.
3287
3288Usually accessed via the C<SvPVutf8> macro.
3289
3290=cut
3291*/
645c22ef 3292
7340a771 3293char *
5aaab254 3294Perl_sv_2pvutf8(pTHX_ SV *sv, STRLEN *const lp)
7340a771 3295{
7918f24d
NC
3296 PERL_ARGS_ASSERT_SV_2PVUTF8;
3297
4499db73
FC
3298 if (((SvREADONLY(sv) || SvFAKE(sv)) && !SvIsCOW(sv))
3299 || isGV_with_GP(sv) || SvROK(sv))
fe46cbda 3300 sv = sv_mortalcopy(sv);
4bac9ae4
CS
3301 else
3302 SvGETMAGIC(sv);
3303 sv_utf8_upgrade_nomg(sv);
c3ec315f 3304 return lp ? SvPV_nomg(sv,*lp) : SvPV_nomg_nolen(sv);
7340a771 3305}
1c846c1f 3306
7ee2227d 3307
645c22ef
DM
3308/*
3309=for apidoc sv_2bool
3310
796b6530
KW
3311This macro is only used by C<sv_true()> or its macro equivalent, and only if
3312the latter's argument is neither C<SvPOK>, C<SvIOK> nor C<SvNOK>.
3313It calls C<sv_2bool_flags> with the C<SV_GMAGIC> flag.
06c841cf
FC
3314
3315=for apidoc sv_2bool_flags
3316
796b6530
KW
3317This function is only used by C<sv_true()> and friends, and only if
3318the latter's argument is neither C<SvPOK>, C<SvIOK> nor C<SvNOK>. If the flags
3319contain C<SV_GMAGIC>, then it does an C<mg_get()> first.
06c841cf 3320
645c22ef
DM
3321
3322=cut
3323*/
3324
463ee0b2 3325bool
9d176cd8 3326Perl_sv_2bool_flags(pTHX_ SV *sv, I32 flags)
463ee0b2 3327{
06c841cf 3328 PERL_ARGS_ASSERT_SV_2BOOL_FLAGS;
7918f24d 3329
9d176cd8 3330 restart:
06c841cf 3331 if(flags & SV_GMAGIC) SvGETMAGIC(sv);
463ee0b2 3332
a0d0e21e
LW
3333 if (!SvOK(sv))
3334 return 0;
3335 if (SvROK(sv)) {
fabdb6c0 3336 if (SvAMAGIC(sv)) {
31d632c3 3337 SV * const tmpsv = AMG_CALLunary(sv, bool__amg);
9d176cd8
DD
3338 if (tmpsv && (!SvROK(tmpsv) || (SvRV(tmpsv) != SvRV(sv)))) {
3339 bool svb;
3340 sv = tmpsv;
3341 if(SvGMAGICAL(sv)) {
3342 flags = SV_GMAGIC;
3343 goto restart; /* call sv_2bool */
3344 }
3345 /* expanded SvTRUE_common(sv, (flags = 0, goto restart)) */
3346 else if(!SvOK(sv)) {
3347 svb = 0;
3348 }
3349 else if(SvPOK(sv)) {
3350 svb = SvPVXtrue(sv);
3351 }
3352 else if((SvFLAGS(sv) & (SVf_IOK|SVf_NOK))) {
3353 svb = (SvIOK(sv) && SvIVX(sv) != 0)
659c4b96 3354 || (SvNOK(sv) && SvNVX(sv) != 0.0);
9d176cd8
DD
3355 }
3356 else {
3357 flags = 0;
3358 goto restart; /* call sv_2bool_nomg */
3359 }
3360 return cBOOL(svb);
3361 }
fabdb6c0 3362 }
e8f01ee5
DM
3363 assert(SvRV(sv));
3364 return TRUE;
a0d0e21e 3365 }
85b7d9b3
FC
3366 if (isREGEXP(sv))
3367 return
3368 RX_WRAPLEN(sv) > 1 || (RX_WRAPLEN(sv) && *RX_WRAPPED(sv) != '0');
4bac9ae4 3369 return SvTRUE_common(sv, isGV_with_GP(sv) ? 1 : 0);
79072805
LW
3370}
3371
c461cf8f
JH
3372/*
3373=for apidoc sv_utf8_upgrade
3374
78ea37eb 3375Converts the PV of an SV to its UTF-8-encoded form.
645c22ef 3376Forces the SV to string form if it is not already.
2bbc8d55 3377Will C<mg_get> on C<sv> if appropriate.
796b6530 3378Always sets the C<SvUTF8> flag to avoid future validity checks even
2bbc8d55
SP
3379if the whole string is the same in UTF-8 as not.
3380Returns the number of bytes in the converted string
c461cf8f 3381
0efd0472 3382This is not a general purpose byte encoding to Unicode interface:
13a6c0e0
JH
3383use the Encode extension for that.
3384
fe749c9a
KW
3385=for apidoc sv_utf8_upgrade_nomg
3386
796b6530 3387Like C<sv_utf8_upgrade>, but doesn't do magic on C<sv>.
fe749c9a 3388
8d6d96c1
HS
3389=for apidoc sv_utf8_upgrade_flags
3390
78ea37eb 3391Converts the PV of an SV to its UTF-8-encoded form.
645c22ef 3392Forces the SV to string form if it is not already.
8d6d96c1 3393Always sets the SvUTF8 flag to avoid future validity checks even
960b0271
FC
3394if all the bytes are invariant in UTF-8.
3395If C<flags> has C<SV_GMAGIC> bit set,
2bbc8d55 3396will C<mg_get> on C<sv> if appropriate, else not.
2a590426 3397
796b6530 3398If C<flags> has C<SV_FORCE_UTF8_UPGRADE> set, this function assumes that the PV
2a590426
KW
3399will expand when converted to UTF-8, and skips the extra work of checking for
3400that. Typically this flag is used by a routine that has already parsed the
3401string and found such characters, and passes this information on so that the
3402work doesn't have to be repeated.
3403
3404Returns the number of bytes in the converted string.
8d6d96c1 3405
0efd0472 3406This is not a general purpose byte encoding to Unicode interface:
13a6c0e0
JH
3407use the Encode extension for that.
3408
2a590426 3409=for apidoc sv_utf8_upgrade_flags_grow
b3ab6785 3410
796b6530
KW
3411Like C<sv_utf8_upgrade_flags>, but has an additional parameter C<extra>, which is
3412the number of unused bytes the string of C<sv> is guaranteed to have free after
2a590426
KW
3413it upon return. This allows the caller to reserve extra space that it intends
3414to fill, to avoid extra grows.
b3ab6785 3415
2a590426
KW
3416C<sv_utf8_upgrade>, C<sv_utf8_upgrade_nomg>, and C<sv_utf8_upgrade_flags>
3417are implemented in terms of this function.
3418
3419Returns the number of bytes in the converted string (not including the spares).
3420
3421=cut
b3ab6785
KW
3422
3423(One might think that the calling routine could pass in the position of the
2a590426
KW
3424first variant character when it has set SV_FORCE_UTF8_UPGRADE, so it wouldn't
3425have to be found again. But that is not the case, because typically when the
3426caller is likely to use this flag, it won't be calling this routine unless it
3427finds something that won't fit into a byte. Otherwise it tries to not upgrade
3428and just use bytes. But some things that do fit into a byte are variants in
3429utf8, and the caller may not have been keeping track of these.)
b3ab6785 3430
6602b933
KW
3431If the routine itself changes the string, it adds a trailing C<NUL>. Such a
3432C<NUL> isn't guaranteed due to having other routines do the work in some input
3433cases, or if the input is already flagged as being in utf8.
b3ab6785
KW
3434
3435The speed of this could perhaps be improved for many cases if someone wanted to
3436write a fast function that counts the number of variant characters in a string,
3437especially if it could return the position of the first one.
3438
8d6d96c1
HS
3439*/
3440
3441STRLEN
5aaab254 3442Perl_sv_utf8_upgrade_flags_grow(pTHX_ SV *const sv, const I32 flags, STRLEN extra)
8d6d96c1 3443{
b3ab6785 3444 PERL_ARGS_ASSERT_SV_UTF8_UPGRADE_FLAGS_GROW;
7918f24d 3445
808c356f
RGS
3446 if (sv == &PL_sv_undef)
3447 return 0;
892f9127 3448 if (!SvPOK_nog(sv)) {
e0e62c2a 3449 STRLEN len = 0;
d52b7888
NC
3450 if (SvREADONLY(sv) && (SvPOKp(sv) || SvIOKp(sv) || SvNOKp(sv))) {
3451 (void) sv_2pv_flags(sv,&len, flags);
b3ab6785
KW
3452 if (SvUTF8(sv)) {
3453 if (extra) SvGROW(sv, SvCUR(sv) + extra);
d52b7888 3454 return len;
b3ab6785 3455 }
d52b7888 3456 } else {
33fb6f35 3457 (void) SvPV_force_flags(sv,len,flags & SV_GMAGIC);
d52b7888 3458 }
e0e62c2a 3459 }
4411f3b6 3460
f5cee72b 3461 if (SvUTF8(sv)) {
b3ab6785 3462 if (extra) SvGROW(sv, SvCUR(sv) + extra);
5fec3b1d 3463 return SvCUR(sv);
f5cee72b 3464 }
5fec3b1d 3465
765f542d 3466 if (SvIsCOW(sv)) {
c56ed9f6 3467 S_sv_uncow(aTHX_ sv, 0);
db42d148
NIS
3468 }
3469
4e93345f
KW
3470 if (SvCUR(sv) == 0) {
3471 if (extra) SvGROW(sv, extra);
3472 } else { /* Assume Latin-1/EBCDIC */
c4e7c712 3473 /* This function could be much more efficient if we
2bbc8d55 3474 * had a FLAG in SVs to signal if there are any variant
c4e7c712 3475 * chars in the PV. Given that there isn't such a flag
b3ab6785
KW
3476 * make the loop as fast as possible (although there are certainly ways
3477 * to speed this up, eg. through vectorization) */
3478 U8 * s = (U8 *) SvPVX_const(sv);
3479 U8 * e = (U8 *) SvEND(sv);
3480 U8 *t = s;
dc772057 3481 STRLEN two_byte_count;
c4e7c712 3482
dc772057
KW
3483 if (flags & SV_FORCE_UTF8_UPGRADE) {
3484 two_byte_count = 0;
3485 }
3486 else {
3487 if (is_utf8_invariant_string_loc(s, SvCUR(sv), (const U8 **) &t)) {
3488
3489 /* utf8 conversion not needed because all are invariants. Mark
3490 * as UTF-8 even if no variant - saves scanning loop */
3491 SvUTF8_on(sv);
3492 if (extra) SvGROW(sv, SvCUR(sv) + extra);
3493 return SvCUR(sv);
3494 }
b3ab6785 3495
dc772057
KW
3496 /* Here, there is at least one variant, and t points to the first
3497 * one */
3498 two_byte_count = 1;
3499 }
b3ab6785 3500
dc772057
KW
3501 /* Note that the incoming SV may not have a trailing '\0', as certain
3502 * code in pp_formline can send us partially built SVs.
3503 *
3504 * Here, the string should be converted to utf8, either because of an
3505 * input flag (which causes two_byte_count to be set to 0), or because
3506 * a character that requires 2 bytes was found (two_byte_count = 1). t
3507 * points either to the beginning of the string (if we didn't examine
3508 * anything), or to the first variant. In either case, everything from
3509 * s to t - 1 will occupy only 1 byte each on output.
b3ab6785
KW
3510 *
3511 * There are two main ways to convert. One is to create a new string
3512 * and go through the input starting from the beginning, appending each
3513 * converted value onto the new string as we go along. It's probably
3514 * best to allocate enough space in the string for the worst possible
3515 * case rather than possibly running out of space and having to
3516 * reallocate and then copy what we've done so far. Since everything
3517 * from s to t - 1 is invariant, the destination can be initialized
3518 * with these using a fast memory copy
3519 *
76d1063e 3520 * The other way is to figure out exactly how big the string should be,
b3ab6785
KW
3521 * by parsing the entire input. Then you don't have to make it big
3522 * enough to handle the worst possible case, and more importantly, if
3523 * the string you already have is large enough, you don't have to
3524 * allocate a new string, you can copy the last character in the input
3525 * string to the final position(s) that will be occupied by the
3526 * converted string and go backwards, stopping at t, since everything
3527 * before that is invariant.
3528 *
3529 * There are advantages and disadvantages to each method.
3530 *
3531 * In the first method, we can allocate a new string, do the memory
3532 * copy from the s to t - 1, and then proceed through the rest of the
3533 * string byte-by-byte.
3534 *
3535 * In the second method, we proceed through the rest of the input
3536 * string just calculating how big the converted string will be. Then
3537 * there are two cases:
3538 * 1) if the string has enough extra space to handle the converted
3539 * value. We go backwards through the string, converting until we
3540 * get to the position we are at now, and then stop. If this
3541 * position is far enough along in the string, this method is
76d1063e
KW
3542 * faster than the first method above. If the memory copy were
3543 * the same speed as the byte-by-byte loop, that position would be
3544 * about half-way, as at the half-way mark, parsing to the end and
3545 * back is one complete string's parse, the same amount as
3546 * starting over and going all the way through. Actually, it
3547 * would be somewhat less than half-way, as it's faster to just
3548 * count bytes than to also copy, and we don't have the overhead
3549 * of allocating a new string, changing the scalar to use it, and
3550 * freeing the existing one. But if the memory copy is fast, the
3551 * break-even point is somewhere after half way. The counting
3552 * loop could be sped up by vectorization, etc, to move the
3553 * break-even point further towards the beginning.
b3ab6785
KW
3554 * 2) if the string doesn't have enough space to handle the converted
3555 * value. A new string will have to be allocated, and one might
3556 * as well, given that, start from the beginning doing the first
3557 * method. We've spent extra time parsing the string and in
3558 * exchange all we've gotten is that we know precisely how big to
3559 * make the new one. Perl is more optimized for time than space,
3560 * so this case is a loser.
3561 * So what I've decided to do is not use the 2nd method unless it is
3562 * guaranteed that a new string won't have to be allocated, assuming
3563 * the worst case. I also decided not to put any more conditions on it
3564 * than this, for now. It seems likely that, since the worst case is
3565 * twice as big as the unknown portion of the string (plus 1), we won't
3566 * be guaranteed enough space, causing us to go to the first method,
3567 * unless the string is short, or the first variant character is near
3568 * the end of it. In either of these cases, it seems best to use the
3569 * 2nd method. The only circumstance I can think of where this would
3570 * be really slower is if the string had once had much more data in it
3571 * than it does now, but there is still a substantial amount in it */
3572
3573 {
3574 STRLEN invariant_head = t - s;
3575 STRLEN size = invariant_head + (e - t) * 2 + 1 + extra;
3576 if (SvLEN(sv) < size) {
3577
3578 /* Here, have decided to allocate a new string */
3579
3580 U8 *dst;
3581 U8 *d;
3582
3583 Newx(dst, size, U8);
3584
3585 /* If no known invariants at the beginning of the input string,
3586 * set so starts from there. Otherwise, can use memory copy to
3587 * get up to where we are now, and then start from here */
3588
5b26a7b3 3589 if (invariant_head == 0) {