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a0d0e21e 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 *
4ac71550
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 *
5e045b90
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"
9d9a81f0
CB
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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FC
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
YO
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
f8c7b90f 128#ifdef PERL_OLD_COPY_ON_WRITE
765f542d 129#define SV_COW_NEXT_SV(sv) INT2PTR(SV *,SvUVX(sv))
607fa7f2 130#define SV_COW_NEXT_SV_SET(current,next) SvUV_set(current, PTR2UV(next))
765f542d 131#endif
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132
133/* ============================================================================
134
135=head1 Allocation and deallocation of SVs.
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136An SV (or AV, HV, etc.) is allocated in two parts: the head (struct
137sv, av, hv...) contains type and reference count information, and for
138many types, a pointer to the body (struct xrv, xpv, xpviv...), which
139contains fields specific to each type. Some types store all they need
140in the head, so don't have a body.
141
486ec47a 142In all but the most memory-paranoid configurations (ex: PURIFY), heads
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143and bodies are allocated out of arenas, which by default are
144approximately 4K chunks of memory parcelled up into N heads or bodies.
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145Sv-bodies are allocated by their sv-type, guaranteeing size
146consistency needed to allocate safely from arrays.
147
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148For SV-heads, the first slot in each arena is reserved, and holds a
149link to the next arena, some flags, and a note of the number of slots.
150Snaked through each arena chain is a linked list of free items; when
151this becomes empty, an extra arena is allocated and divided up into N
152items which are threaded into the free list.
153
154SV-bodies are similar, but they use arena-sets by default, which
155separate the link and info from the arena itself, and reclaim the 1st
156slot in the arena. SV-bodies are further described later.
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157
158The following global variables are associated with arenas:
159
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160 PL_sv_arenaroot pointer to list of SV arenas
161 PL_sv_root pointer to list of free SV structures
645c22ef 162
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163 PL_body_arenas head of linked-list of body arenas
164 PL_body_roots[] array of pointers to list of free bodies of svtype
165 arrays are indexed by the svtype needed
93e68bfb 166
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167A few special SV heads are not allocated from an arena, but are
168instead directly created in the interpreter structure, eg PL_sv_undef.
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169The size of arenas can be changed from the default by setting
170PERL_ARENA_SIZE appropriately at compile time.
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171
172The SV arena serves the secondary purpose of allowing still-live SVs
173to be located and destroyed during final cleanup.
174
175At the lowest level, the macros new_SV() and del_SV() grab and free
176an SV head. (If debugging with -DD, del_SV() calls the function S_del_sv()
177to return the SV to the free list with error checking.) new_SV() calls
178more_sv() / sv_add_arena() to add an extra arena if the free list is empty.
179SVs in the free list have their SvTYPE field set to all ones.
180
ff276b08 181At the time of very final cleanup, sv_free_arenas() is called from
645c22ef 182perl_destruct() to physically free all the arenas allocated since the
6a93a7e5 183start of the interpreter.
645c22ef 184
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185The function visit() scans the SV arenas list, and calls a specified
186function for each SV it finds which is still live - ie which has an SvTYPE
187other than all 1's, and a non-zero SvREFCNT. visit() is used by the
188following functions (specified as [function that calls visit()] / [function
189called by visit() for each SV]):
190
191 sv_report_used() / do_report_used()
f2524eef 192 dump all remaining SVs (debugging aid)
645c22ef 193
e4487e9b 194 sv_clean_objs() / do_clean_objs(),do_clean_named_objs(),
e76981f9 195 do_clean_named_io_objs(),do_curse()
645c22ef 196 Attempt to free all objects pointed to by RVs,
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197 try to do the same for all objects indir-
198 ectly referenced by typeglobs too, and
199 then do a final sweep, cursing any
200 objects that remain. Called once from
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201 perl_destruct(), prior to calling sv_clean_all()
202 below.
203
204 sv_clean_all() / do_clean_all()
205 SvREFCNT_dec(sv) each remaining SV, possibly
206 triggering an sv_free(). It also sets the
207 SVf_BREAK flag on the SV to indicate that the
208 refcnt has been artificially lowered, and thus
209 stopping sv_free() from giving spurious warnings
210 about SVs which unexpectedly have a refcnt
211 of zero. called repeatedly from perl_destruct()
212 until there are no SVs left.
213
93e68bfb 214=head2 Arena allocator API Summary
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215
216Private API to rest of sv.c
217
218 new_SV(), del_SV(),
219
df0f0429 220 new_XPVNV(), del_XPVGV(),
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221 etc
222
223Public API:
224
8cf8f3d1 225 sv_report_used(), sv_clean_objs(), sv_clean_all(), sv_free_arenas()
645c22ef 226
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227=cut
228
3e8320cc 229 * ========================================================================= */
645c22ef 230
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231/*
232 * "A time to plant, and a time to uproot what was planted..."
233 */
234
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235#ifdef PERL_MEM_LOG
236# define MEM_LOG_NEW_SV(sv, file, line, func) \
237 Perl_mem_log_new_sv(sv, file, line, func)
238# define MEM_LOG_DEL_SV(sv, file, line, func) \
239 Perl_mem_log_del_sv(sv, file, line, func)
240#else
241# define MEM_LOG_NEW_SV(sv, file, line, func) NOOP
242# define MEM_LOG_DEL_SV(sv, file, line, func) NOOP
243#endif
244
fd0854ff 245#ifdef DEBUG_LEAKING_SCALARS
484e6108
FC
246# define FREE_SV_DEBUG_FILE(sv) STMT_START { \
247 if ((sv)->sv_debug_file) PerlMemShared_free((sv)->sv_debug_file); \
248 } STMT_END
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MHM
249# define DEBUG_SV_SERIAL(sv) \
250 DEBUG_m(PerlIO_printf(Perl_debug_log, "0x%"UVxf": (%05ld) del_SV\n", \
251 PTR2UV(sv), (long)(sv)->sv_debug_serial))
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252#else
253# define FREE_SV_DEBUG_FILE(sv)
d7a2c63c 254# define DEBUG_SV_SERIAL(sv) NOOP
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DM
255#endif
256
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NC
257#ifdef PERL_POISON
258# define SvARENA_CHAIN(sv) ((sv)->sv_u.svu_rv)
daba3364 259# define SvARENA_CHAIN_SET(sv,val) (sv)->sv_u.svu_rv = MUTABLE_SV((val))
48614a46
NC
260/* Whilst I'd love to do this, it seems that things like to check on
261 unreferenced scalars
7e337ee0 262# define POSION_SV_HEAD(sv) PoisonNew(sv, 1, struct STRUCT_SV)
48614a46 263*/
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JH
264# define POSION_SV_HEAD(sv) PoisonNew(&SvANY(sv), 1, void *), \
265 PoisonNew(&SvREFCNT(sv), 1, U32)
48614a46
NC
266#else
267# define SvARENA_CHAIN(sv) SvANY(sv)
3eef1deb 268# define SvARENA_CHAIN_SET(sv,val) SvANY(sv) = (void *)(val)
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NC
269# define POSION_SV_HEAD(sv)
270#endif
271
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DM
272/* Mark an SV head as unused, and add to free list.
273 *
274 * If SVf_BREAK is set, skip adding it to the free list, as this SV had
275 * its refcount artificially decremented during global destruction, so
276 * there may be dangling pointers to it. The last thing we want in that
277 * case is for it to be reused. */
278
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279#define plant_SV(p) \
280 STMT_START { \
990198f0 281 const U32 old_flags = SvFLAGS(p); \
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MHM
282 MEM_LOG_DEL_SV(p, __FILE__, __LINE__, FUNCTION__); \
283 DEBUG_SV_SERIAL(p); \
fd0854ff 284 FREE_SV_DEBUG_FILE(p); \
48614a46 285 POSION_SV_HEAD(p); \
053fc874 286 SvFLAGS(p) = SVTYPEMASK; \
990198f0 287 if (!(old_flags & SVf_BREAK)) { \
3eef1deb 288 SvARENA_CHAIN_SET(p, PL_sv_root); \
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289 PL_sv_root = (p); \
290 } \
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291 --PL_sv_count; \
292 } STMT_END
a0d0e21e 293
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294#define uproot_SV(p) \
295 STMT_START { \
296 (p) = PL_sv_root; \
daba3364 297 PL_sv_root = MUTABLE_SV(SvARENA_CHAIN(p)); \
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298 ++PL_sv_count; \
299 } STMT_END
300
645c22ef 301
cac9b346
NC
302/* make some more SVs by adding another arena */
303
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NC
304STATIC SV*
305S_more_sv(pTHX)
306{
307 SV* sv;
9a87bd09
NC
308 char *chunk; /* must use New here to match call to */
309 Newx(chunk,PERL_ARENA_SIZE,char); /* Safefree() in sv_free_arenas() */
310 sv_add_arena(chunk, PERL_ARENA_SIZE, 0);
cac9b346
NC
311 uproot_SV(sv);
312 return sv;
313}
314
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315/* new_SV(): return a new, empty SV head */
316
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317#ifdef DEBUG_LEAKING_SCALARS
318/* provide a real function for a debugger to play with */
319STATIC SV*
d7a2c63c 320S_new_SV(pTHX_ const char *file, int line, const char *func)
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DM
321{
322 SV* sv;
323
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324 if (PL_sv_root)
325 uproot_SV(sv);
326 else
cac9b346 327 sv = S_more_sv(aTHX);
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328 SvANY(sv) = 0;
329 SvREFCNT(sv) = 1;
330 SvFLAGS(sv) = 0;
fd0854ff 331 sv->sv_debug_optype = PL_op ? PL_op->op_type : 0;
e385c3bf
DM
332 sv->sv_debug_line = (U16) (PL_parser && PL_parser->copline != NOLINE
333 ? PL_parser->copline
334 : PL_curcop
f24aceb1
DM
335 ? CopLINE(PL_curcop)
336 : 0
e385c3bf 337 );
fd0854ff 338 sv->sv_debug_inpad = 0;
cd676548 339 sv->sv_debug_parent = NULL;
484e6108 340 sv->sv_debug_file = PL_curcop ? savesharedpv(CopFILE(PL_curcop)): NULL;
d7a2c63c
MHM
341
342 sv->sv_debug_serial = PL_sv_serial++;
343
344 MEM_LOG_NEW_SV(sv, file, line, func);
345 DEBUG_m(PerlIO_printf(Perl_debug_log, "0x%"UVxf": (%05ld) new_SV (from %s:%d [%s])\n",
346 PTR2UV(sv), (long)sv->sv_debug_serial, file, line, func));
347
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348 return sv;
349}
d7a2c63c 350# define new_SV(p) (p)=S_new_SV(aTHX_ __FILE__, __LINE__, FUNCTION__)
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351
352#else
353# define new_SV(p) \
053fc874 354 STMT_START { \
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355 if (PL_sv_root) \
356 uproot_SV(p); \
357 else \
cac9b346 358 (p) = S_more_sv(aTHX); \
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359 SvANY(p) = 0; \
360 SvREFCNT(p) = 1; \
361 SvFLAGS(p) = 0; \
d7a2c63c 362 MEM_LOG_NEW_SV(p, __FILE__, __LINE__, FUNCTION__); \
053fc874 363 } STMT_END
eba0f806 364#endif
463ee0b2 365
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366
367/* del_SV(): return an empty SV head to the free list */
368
a0d0e21e 369#ifdef DEBUGGING
4561caa4 370
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371#define del_SV(p) \
372 STMT_START { \
aea4f609 373 if (DEBUG_D_TEST) \
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374 del_sv(p); \
375 else \
376 plant_SV(p); \
053fc874 377 } STMT_END
a0d0e21e 378
76e3520e 379STATIC void
cea2e8a9 380S_del_sv(pTHX_ SV *p)
463ee0b2 381{
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NC
382 PERL_ARGS_ASSERT_DEL_SV;
383
aea4f609 384 if (DEBUG_D_TEST) {
4633a7c4 385 SV* sva;
a3b680e6 386 bool ok = 0;
daba3364 387 for (sva = PL_sv_arenaroot; sva; sva = MUTABLE_SV(SvANY(sva))) {
53c1dcc0
AL
388 const SV * const sv = sva + 1;
389 const SV * const svend = &sva[SvREFCNT(sva)];
c0ff570e 390 if (p >= sv && p < svend) {
a0d0e21e 391 ok = 1;
c0ff570e
NC
392 break;
393 }
a0d0e21e
LW
394 }
395 if (!ok) {
9b387841
NC
396 Perl_ck_warner_d(aTHX_ packWARN(WARN_INTERNAL),
397 "Attempt to free non-arena SV: 0x%"UVxf
398 pTHX__FORMAT, PTR2UV(p) pTHX__VALUE);
a0d0e21e
LW
399 return;
400 }
401 }
4561caa4 402 plant_SV(p);
463ee0b2 403}
a0d0e21e 404
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CS
405#else /* ! DEBUGGING */
406
407#define del_SV(p) plant_SV(p)
408
409#endif /* DEBUGGING */
463ee0b2 410
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411
412/*
ccfc67b7
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413=head1 SV Manipulation Functions
414
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415=for apidoc sv_add_arena
416
417Given a chunk of memory, link it to the head of the list of arenas,
418and split it into a list of free SVs.
419
420=cut
421*/
422
d2bd4e7f
NC
423static void
424S_sv_add_arena(pTHX_ char *const ptr, const U32 size, const U32 flags)
463ee0b2 425{
daba3364 426 SV *const sva = MUTABLE_SV(ptr);
eb578fdb
KW
427 SV* sv;
428 SV* svend;
4633a7c4 429
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NC
430 PERL_ARGS_ASSERT_SV_ADD_ARENA;
431
4633a7c4 432 /* The first SV in an arena isn't an SV. */
3280af22 433 SvANY(sva) = (void *) PL_sv_arenaroot; /* ptr to next arena */
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LW
434 SvREFCNT(sva) = size / sizeof(SV); /* number of SV slots */
435 SvFLAGS(sva) = flags; /* FAKE if not to be freed */
436
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437 PL_sv_arenaroot = sva;
438 PL_sv_root = sva + 1;
4633a7c4
LW
439
440 svend = &sva[SvREFCNT(sva) - 1];
441 sv = sva + 1;
463ee0b2 442 while (sv < svend) {
3eef1deb 443 SvARENA_CHAIN_SET(sv, (sv + 1));
03e36789 444#ifdef DEBUGGING
978b032e 445 SvREFCNT(sv) = 0;
03e36789 446#endif
4b69cbe3 447 /* Must always set typemask because it's always checked in on cleanup
03e36789 448 when the arenas are walked looking for objects. */
8990e307 449 SvFLAGS(sv) = SVTYPEMASK;
463ee0b2
LW
450 sv++;
451 }
3eef1deb 452 SvARENA_CHAIN_SET(sv, 0);
03e36789
NC
453#ifdef DEBUGGING
454 SvREFCNT(sv) = 0;
455#endif
4633a7c4
LW
456 SvFLAGS(sv) = SVTYPEMASK;
457}
458
055972dc
DM
459/* visit(): call the named function for each non-free SV in the arenas
460 * whose flags field matches the flags/mask args. */
645c22ef 461
5226ed68 462STATIC I32
de37a194 463S_visit(pTHX_ SVFUNC_t f, const U32 flags, const U32 mask)
8990e307 464{
4633a7c4 465 SV* sva;
5226ed68 466 I32 visited = 0;
8990e307 467
7918f24d
NC
468 PERL_ARGS_ASSERT_VISIT;
469
daba3364 470 for (sva = PL_sv_arenaroot; sva; sva = MUTABLE_SV(SvANY(sva))) {
eb578fdb
KW
471 const SV * const svend = &sva[SvREFCNT(sva)];
472 SV* sv;
4561caa4 473 for (sv = sva + 1; sv < svend; ++sv) {
e4787c0c 474 if (SvTYPE(sv) != (svtype)SVTYPEMASK
055972dc
DM
475 && (sv->sv_flags & mask) == flags
476 && SvREFCNT(sv))
477 {
942481a7 478 (*f)(aTHX_ sv);
5226ed68
JH
479 ++visited;
480 }
8990e307
LW
481 }
482 }
5226ed68 483 return visited;
8990e307
LW
484}
485
758a08c3
JH
486#ifdef DEBUGGING
487
645c22ef
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488/* called by sv_report_used() for each live SV */
489
490static void
5fa45a31 491do_report_used(pTHX_ SV *const sv)
645c22ef 492{
e4787c0c 493 if (SvTYPE(sv) != (svtype)SVTYPEMASK) {
645c22ef
DM
494 PerlIO_printf(Perl_debug_log, "****\n");
495 sv_dump(sv);
496 }
497}
758a08c3 498#endif
645c22ef
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499
500/*
501=for apidoc sv_report_used
502
fde67290 503Dump the contents of all SVs not yet freed (debugging aid).
645c22ef
DM
504
505=cut
506*/
507
8990e307 508void
864dbfa3 509Perl_sv_report_used(pTHX)
4561caa4 510{
ff270d3a 511#ifdef DEBUGGING
055972dc 512 visit(do_report_used, 0, 0);
96a5add6
AL
513#else
514 PERL_UNUSED_CONTEXT;
ff270d3a 515#endif
4561caa4
CS
516}
517
645c22ef
DM
518/* called by sv_clean_objs() for each live SV */
519
520static void
de37a194 521do_clean_objs(pTHX_ SV *const ref)
645c22ef 522{
ea724faa
NC
523 assert (SvROK(ref));
524 {
823a54a3
AL
525 SV * const target = SvRV(ref);
526 if (SvOBJECT(target)) {
527 DEBUG_D((PerlIO_printf(Perl_debug_log, "Cleaning object ref:\n "), sv_dump(ref)));
528 if (SvWEAKREF(ref)) {
529 sv_del_backref(target, ref);
530 SvWEAKREF_off(ref);
531 SvRV_set(ref, NULL);
532 } else {
533 SvROK_off(ref);
534 SvRV_set(ref, NULL);
fc2b2dca 535 SvREFCNT_dec_NN(target);
823a54a3 536 }
645c22ef
DM
537 }
538 }
645c22ef
DM
539}
540
645c22ef 541
e4487e9b
DM
542/* clear any slots in a GV which hold objects - except IO;
543 * called by sv_clean_objs() for each live GV */
544
645c22ef 545static void
f30de749 546do_clean_named_objs(pTHX_ SV *const sv)
645c22ef 547{
57ef47cc 548 SV *obj;
ea724faa 549 assert(SvTYPE(sv) == SVt_PVGV);
d011219a 550 assert(isGV_with_GP(sv));
57ef47cc
DM
551 if (!GvGP(sv))
552 return;
553
554 /* freeing GP entries may indirectly free the current GV;
555 * hold onto it while we mess with the GP slots */
556 SvREFCNT_inc(sv);
557
558 if ( ((obj = GvSV(sv) )) && SvOBJECT(obj)) {
559 DEBUG_D((PerlIO_printf(Perl_debug_log,
560 "Cleaning named glob SV object:\n "), sv_dump(obj)));
561 GvSV(sv) = NULL;
fc2b2dca 562 SvREFCNT_dec_NN(obj);
57ef47cc
DM
563 }
564 if ( ((obj = MUTABLE_SV(GvAV(sv)) )) && SvOBJECT(obj)) {
565 DEBUG_D((PerlIO_printf(Perl_debug_log,
566 "Cleaning named glob AV object:\n "), sv_dump(obj)));
567 GvAV(sv) = NULL;
fc2b2dca 568 SvREFCNT_dec_NN(obj);
57ef47cc
DM
569 }
570 if ( ((obj = MUTABLE_SV(GvHV(sv)) )) && SvOBJECT(obj)) {
571 DEBUG_D((PerlIO_printf(Perl_debug_log,
572 "Cleaning named glob HV object:\n "), sv_dump(obj)));
573 GvHV(sv) = NULL;
fc2b2dca 574 SvREFCNT_dec_NN(obj);
57ef47cc
DM
575 }
576 if ( ((obj = MUTABLE_SV(GvCV(sv)) )) && SvOBJECT(obj)) {
577 DEBUG_D((PerlIO_printf(Perl_debug_log,
578 "Cleaning named glob CV object:\n "), sv_dump(obj)));
c43ae56f 579 GvCV_set(sv, NULL);
fc2b2dca 580 SvREFCNT_dec_NN(obj);
57ef47cc 581 }
fc2b2dca 582 SvREFCNT_dec_NN(sv); /* undo the inc above */
e4487e9b
DM
583}
584
68b590d9 585/* clear any IO slots in a GV which hold objects (except stderr, defout);
e4487e9b
DM
586 * called by sv_clean_objs() for each live GV */
587
588static void
589do_clean_named_io_objs(pTHX_ SV *const sv)
590{
e4487e9b
DM
591 SV *obj;
592 assert(SvTYPE(sv) == SVt_PVGV);
593 assert(isGV_with_GP(sv));
68b590d9 594 if (!GvGP(sv) || sv == (SV*)PL_stderrgv || sv == (SV*)PL_defoutgv)
e4487e9b
DM
595 return;
596
597 SvREFCNT_inc(sv);
57ef47cc
DM
598 if ( ((obj = MUTABLE_SV(GvIO(sv)) )) && SvOBJECT(obj)) {
599 DEBUG_D((PerlIO_printf(Perl_debug_log,
600 "Cleaning named glob IO object:\n "), sv_dump(obj)));
601 GvIOp(sv) = NULL;
fc2b2dca 602 SvREFCNT_dec_NN(obj);
645c22ef 603 }
fc2b2dca 604 SvREFCNT_dec_NN(sv); /* undo the inc above */
645c22ef 605}
645c22ef 606
4155e4fe
FC
607/* Void wrapper to pass to visit() */
608static void
609do_curse(pTHX_ SV * const sv) {
c2910e6c
FC
610 if ((PL_stderrgv && GvGP(PL_stderrgv) && (SV*)GvIO(PL_stderrgv) == sv)
611 || (PL_defoutgv && GvGP(PL_defoutgv) && (SV*)GvIO(PL_defoutgv) == sv))
4155e4fe
FC
612 return;
613 (void)curse(sv, 0);
614}
615
645c22ef
DM
616/*
617=for apidoc sv_clean_objs
618
fde67290 619Attempt to destroy all objects not yet freed.
645c22ef
DM
620
621=cut
622*/
623
4561caa4 624void
864dbfa3 625Perl_sv_clean_objs(pTHX)
4561caa4 626{
68b590d9 627 GV *olddef, *olderr;
3280af22 628 PL_in_clean_objs = TRUE;
055972dc 629 visit(do_clean_objs, SVf_ROK, SVf_ROK);
e4487e9b
DM
630 /* Some barnacles may yet remain, clinging to typeglobs.
631 * Run the non-IO destructors first: they may want to output
632 * error messages, close files etc */
d011219a 633 visit(do_clean_named_objs, SVt_PVGV|SVpgv_GP, SVTYPEMASK|SVp_POK|SVpgv_GP);
e4487e9b 634 visit(do_clean_named_io_objs, SVt_PVGV|SVpgv_GP, SVTYPEMASK|SVp_POK|SVpgv_GP);
4155e4fe
FC
635 /* And if there are some very tenacious barnacles clinging to arrays,
636 closures, or what have you.... */
637 visit(do_curse, SVs_OBJECT, SVs_OBJECT);
68b590d9
DM
638 olddef = PL_defoutgv;
639 PL_defoutgv = NULL; /* disable skip of PL_defoutgv */
640 if (olddef && isGV_with_GP(olddef))
641 do_clean_named_io_objs(aTHX_ MUTABLE_SV(olddef));
642 olderr = PL_stderrgv;
643 PL_stderrgv = NULL; /* disable skip of PL_stderrgv */
644 if (olderr && isGV_with_GP(olderr))
645 do_clean_named_io_objs(aTHX_ MUTABLE_SV(olderr));
646 SvREFCNT_dec(olddef);
3280af22 647 PL_in_clean_objs = FALSE;
4561caa4
CS
648}
649
645c22ef
DM
650/* called by sv_clean_all() for each live SV */
651
652static void
de37a194 653do_clean_all(pTHX_ SV *const sv)
645c22ef 654{
daba3364 655 if (sv == (const SV *) PL_fdpid || sv == (const SV *)PL_strtab) {
cddfcddc 656 /* don't clean pid table and strtab */
d17ea597 657 return;
cddfcddc 658 }
645c22ef
DM
659 DEBUG_D((PerlIO_printf(Perl_debug_log, "Cleaning loops: SV at 0x%"UVxf"\n", PTR2UV(sv)) ));
660 SvFLAGS(sv) |= SVf_BREAK;
fc2b2dca 661 SvREFCNT_dec_NN(sv);
645c22ef
DM
662}
663
664/*
665=for apidoc sv_clean_all
666
667Decrement the refcnt of each remaining SV, possibly triggering a
fde67290 668cleanup. This function may have to be called multiple times to free
ff276b08 669SVs which are in complex self-referential hierarchies.
645c22ef
DM
670
671=cut
672*/
673
5226ed68 674I32
864dbfa3 675Perl_sv_clean_all(pTHX)
8990e307 676{
5226ed68 677 I32 cleaned;
3280af22 678 PL_in_clean_all = TRUE;
055972dc 679 cleaned = visit(do_clean_all, 0,0);
5226ed68 680 return cleaned;
8990e307 681}
463ee0b2 682
5e258f8c
JC
683/*
684 ARENASETS: a meta-arena implementation which separates arena-info
685 into struct arena_set, which contains an array of struct
686 arena_descs, each holding info for a single arena. By separating
687 the meta-info from the arena, we recover the 1st slot, formerly
688 borrowed for list management. The arena_set is about the size of an
39244528 689 arena, avoiding the needless malloc overhead of a naive linked-list.
5e258f8c
JC
690
691 The cost is 1 arena-set malloc per ~320 arena-mallocs, + the unused
692 memory in the last arena-set (1/2 on average). In trade, we get
693 back the 1st slot in each arena (ie 1.7% of a CV-arena, less for
d2a0f284 694 smaller types). The recovery of the wasted space allows use of
e15dad31
JC
695 small arenas for large, rare body types, by changing array* fields
696 in body_details_by_type[] below.
5e258f8c 697*/
5e258f8c 698struct arena_desc {
398c677b
NC
699 char *arena; /* the raw storage, allocated aligned */
700 size_t size; /* its size ~4k typ */
e5973ed5 701 svtype utype; /* bodytype stored in arena */
5e258f8c
JC
702};
703
e6148039
NC
704struct arena_set;
705
706/* Get the maximum number of elements in set[] such that struct arena_set
e15dad31 707 will fit within PERL_ARENA_SIZE, which is probably just under 4K, and
e6148039
NC
708 therefore likely to be 1 aligned memory page. */
709
710#define ARENAS_PER_SET ((PERL_ARENA_SIZE - sizeof(struct arena_set*) \
711 - 2 * sizeof(int)) / sizeof (struct arena_desc))
5e258f8c
JC
712
713struct arena_set {
714 struct arena_set* next;
0a848332
NC
715 unsigned int set_size; /* ie ARENAS_PER_SET */
716 unsigned int curr; /* index of next available arena-desc */
5e258f8c
JC
717 struct arena_desc set[ARENAS_PER_SET];
718};
719
645c22ef
DM
720/*
721=for apidoc sv_free_arenas
722
fde67290 723Deallocate the memory used by all arenas. Note that all the individual SV
645c22ef
DM
724heads and bodies within the arenas must already have been freed.
725
726=cut
7fefc6c1 727
645c22ef 728*/
4633a7c4 729void
864dbfa3 730Perl_sv_free_arenas(pTHX)
4633a7c4
LW
731{
732 SV* sva;
733 SV* svanext;
0a848332 734 unsigned int i;
4633a7c4
LW
735
736 /* Free arenas here, but be careful about fake ones. (We assume
737 contiguity of the fake ones with the corresponding real ones.) */
738
3280af22 739 for (sva = PL_sv_arenaroot; sva; sva = svanext) {
daba3364 740 svanext = MUTABLE_SV(SvANY(sva));
4633a7c4 741 while (svanext && SvFAKE(svanext))
daba3364 742 svanext = MUTABLE_SV(SvANY(svanext));
4633a7c4
LW
743
744 if (!SvFAKE(sva))
1df70142 745 Safefree(sva);
4633a7c4 746 }
93e68bfb 747
5e258f8c 748 {
0a848332
NC
749 struct arena_set *aroot = (struct arena_set*) PL_body_arenas;
750
751 while (aroot) {
752 struct arena_set *current = aroot;
753 i = aroot->curr;
754 while (i--) {
5e258f8c
JC
755 assert(aroot->set[i].arena);
756 Safefree(aroot->set[i].arena);
757 }
0a848332
NC
758 aroot = aroot->next;
759 Safefree(current);
5e258f8c
JC
760 }
761 }
dc8220bf 762 PL_body_arenas = 0;
fdda85ca 763
0a848332
NC
764 i = PERL_ARENA_ROOTS_SIZE;
765 while (i--)
93e68bfb 766 PL_body_roots[i] = 0;
93e68bfb 767
3280af22
NIS
768 PL_sv_arenaroot = 0;
769 PL_sv_root = 0;
4633a7c4
LW
770}
771
bd81e77b
NC
772/*
773 Here are mid-level routines that manage the allocation of bodies out
774 of the various arenas. There are 5 kinds of arenas:
29489e7c 775
bd81e77b
NC
776 1. SV-head arenas, which are discussed and handled above
777 2. regular body arenas
778 3. arenas for reduced-size bodies
779 4. Hash-Entry arenas
29489e7c 780
bd81e77b
NC
781 Arena types 2 & 3 are chained by body-type off an array of
782 arena-root pointers, which is indexed by svtype. Some of the
783 larger/less used body types are malloced singly, since a large
784 unused block of them is wasteful. Also, several svtypes dont have
785 bodies; the data fits into the sv-head itself. The arena-root
786 pointer thus has a few unused root-pointers (which may be hijacked
787 later for arena types 4,5)
29489e7c 788
bd81e77b
NC
789 3 differs from 2 as an optimization; some body types have several
790 unused fields in the front of the structure (which are kept in-place
791 for consistency). These bodies can be allocated in smaller chunks,
792 because the leading fields arent accessed. Pointers to such bodies
793 are decremented to point at the unused 'ghost' memory, knowing that
794 the pointers are used with offsets to the real memory.
29489e7c 795
d2a0f284
JC
796
797=head1 SV-Body Allocation
798
f554dfc5
MH
799=cut
800
d2a0f284
JC
801Allocation of SV-bodies is similar to SV-heads, differing as follows;
802the allocation mechanism is used for many body types, so is somewhat
803more complicated, it uses arena-sets, and has no need for still-live
804SV detection.
805
806At the outermost level, (new|del)_X*V macros return bodies of the
807appropriate type. These macros call either (new|del)_body_type or
808(new|del)_body_allocated macro pairs, depending on specifics of the
809type. Most body types use the former pair, the latter pair is used to
810allocate body types with "ghost fields".
811
812"ghost fields" are fields that are unused in certain types, and
69ba284b 813consequently don't need to actually exist. They are declared because
d2a0f284
JC
814they're part of a "base type", which allows use of functions as
815methods. The simplest examples are AVs and HVs, 2 aggregate types
816which don't use the fields which support SCALAR semantics.
817
69ba284b 818For these types, the arenas are carved up into appropriately sized
d2a0f284
JC
819chunks, we thus avoid wasted memory for those unaccessed members.
820When bodies are allocated, we adjust the pointer back in memory by the
69ba284b 821size of the part not allocated, so it's as if we allocated the full
d2a0f284
JC
822structure. (But things will all go boom if you write to the part that
823is "not there", because you'll be overwriting the last members of the
824preceding structure in memory.)
825
69ba284b 826We calculate the correction using the STRUCT_OFFSET macro on the first
a05ea1cf 827member present. If the allocated structure is smaller (no initial NV
69ba284b
NC
828actually allocated) then the net effect is to subtract the size of the NV
829from the pointer, to return a new pointer as if an initial NV were actually
a05ea1cf 830allocated. (We were using structures named *_allocated for this, but
69ba284b
NC
831this turned out to be a subtle bug, because a structure without an NV
832could have a lower alignment constraint, but the compiler is allowed to
833optimised accesses based on the alignment constraint of the actual pointer
834to the full structure, for example, using a single 64 bit load instruction
835because it "knows" that two adjacent 32 bit members will be 8-byte aligned.)
d2a0f284 836
a05ea1cf 837This is the same trick as was used for NV and IV bodies. Ironically it
d2a0f284 838doesn't need to be used for NV bodies any more, because NV is now at
5b306eef
DD
839the start of the structure. IV bodies, and also in some builds NV bodies,
840don't need it either, because they are no longer allocated.
d2a0f284
JC
841
842In turn, the new_body_* allocators call S_new_body(), which invokes
843new_body_inline macro, which takes a lock, and takes a body off the
1e30fcd5 844linked list at PL_body_roots[sv_type], calling Perl_more_bodies() if
d2a0f284
JC
845necessary to refresh an empty list. Then the lock is released, and
846the body is returned.
847
99816f8d 848Perl_more_bodies allocates a new arena, and carves it up into an array of N
d2a0f284
JC
849bodies, which it strings into a linked list. It looks up arena-size
850and body-size from the body_details table described below, thus
851supporting the multiple body-types.
852
853If PURIFY is defined, or PERL_ARENA_SIZE=0, arenas are not used, and
854the (new|del)_X*V macros are mapped directly to malloc/free.
855
d2a0f284
JC
856For each sv-type, struct body_details bodies_by_type[] carries
857parameters which control these aspects of SV handling:
858
859Arena_size determines whether arenas are used for this body type, and if
860so, how big they are. PURIFY or PERL_ARENA_SIZE=0 set this field to
861zero, forcing individual mallocs and frees.
862
863Body_size determines how big a body is, and therefore how many fit into
864each arena. Offset carries the body-pointer adjustment needed for
69ba284b 865"ghost fields", and is used in *_allocated macros.
d2a0f284
JC
866
867But its main purpose is to parameterize info needed in
868Perl_sv_upgrade(). The info here dramatically simplifies the function
69ba284b 869vs the implementation in 5.8.8, making it table-driven. All fields
d2a0f284
JC
870are used for this, except for arena_size.
871
872For the sv-types that have no bodies, arenas are not used, so those
873PL_body_roots[sv_type] are unused, and can be overloaded. In
874something of a special case, SVt_NULL is borrowed for HE arenas;
c6f8b1d0 875PL_body_roots[HE_SVSLOT=SVt_NULL] is filled by S_more_he, but the
d2a0f284 876bodies_by_type[SVt_NULL] slot is not used, as the table is not
c6f8b1d0 877available in hv.c.
d2a0f284 878
29489e7c
DM
879*/
880
bd81e77b 881struct body_details {
0fb58b32 882 U8 body_size; /* Size to allocate */
10666ae3 883 U8 copy; /* Size of structure to copy (may be shorter) */
5b306eef
DD
884 U8 offset; /* Size of unalloced ghost fields to first alloced field*/
885 PERL_BITFIELD8 type : 4; /* We have space for a sanity check. */
886 PERL_BITFIELD8 cant_upgrade : 1;/* Cannot upgrade this type */
887 PERL_BITFIELD8 zero_nv : 1; /* zero the NV when upgrading from this */
888 PERL_BITFIELD8 arena : 1; /* Allocated from an arena */
889 U32 arena_size; /* Size of arena to allocate */
bd81e77b 890};
29489e7c 891
bd81e77b
NC
892#define HADNV FALSE
893#define NONV TRUE
29489e7c 894
d2a0f284 895
bd81e77b
NC
896#ifdef PURIFY
897/* With -DPURFIY we allocate everything directly, and don't use arenas.
898 This seems a rather elegant way to simplify some of the code below. */
899#define HASARENA FALSE
900#else
901#define HASARENA TRUE
902#endif
903#define NOARENA FALSE
29489e7c 904
d2a0f284
JC
905/* Size the arenas to exactly fit a given number of bodies. A count
906 of 0 fits the max number bodies into a PERL_ARENA_SIZE.block,
907 simplifying the default. If count > 0, the arena is sized to fit
908 only that many bodies, allowing arenas to be used for large, rare
909 bodies (XPVFM, XPVIO) without undue waste. The arena size is
910 limited by PERL_ARENA_SIZE, so we can safely oversize the
911 declarations.
912 */
95db5f15
MB
913#define FIT_ARENA0(body_size) \
914 ((size_t)(PERL_ARENA_SIZE / body_size) * body_size)
915#define FIT_ARENAn(count,body_size) \
916 ( count * body_size <= PERL_ARENA_SIZE) \
917 ? count * body_size \
918 : FIT_ARENA0 (body_size)
919#define FIT_ARENA(count,body_size) \
cd1dc8e2 920 (U32)(count \
95db5f15 921 ? FIT_ARENAn (count, body_size) \
cd1dc8e2 922 : FIT_ARENA0 (body_size))
d2a0f284 923
bd81e77b
NC
924/* Calculate the length to copy. Specifically work out the length less any
925 final padding the compiler needed to add. See the comment in sv_upgrade
926 for why copying the padding proved to be a bug. */
29489e7c 927
bd81e77b
NC
928#define copy_length(type, last_member) \
929 STRUCT_OFFSET(type, last_member) \
daba3364 930 + sizeof (((type*)SvANY((const SV *)0))->last_member)
29489e7c 931
bd81e77b 932static const struct body_details bodies_by_type[] = {
829cd18a
NC
933 /* HEs use this offset for their arena. */
934 { 0, 0, 0, SVt_NULL, FALSE, NONV, NOARENA, 0 },
d2a0f284 935
db93c0c4
NC
936 /* IVs are in the head, so the allocation size is 0. */
937 { 0,
d2a0f284 938 sizeof(IV), /* This is used to copy out the IV body. */
10666ae3 939 STRUCT_OFFSET(XPVIV, xiv_iv), SVt_IV, FALSE, NONV,
db93c0c4 940 NOARENA /* IVS don't need an arena */, 0
d2a0f284
JC
941 },
942
5b306eef
DD
943#if NVSIZE <= IVSIZE
944 { 0, sizeof(NV),
945 STRUCT_OFFSET(XPVNV, xnv_u),
946 SVt_NV, FALSE, HADNV, NOARENA, 0 },
947#else
6e128786
NC
948 { sizeof(NV), sizeof(NV),
949 STRUCT_OFFSET(XPVNV, xnv_u),
950 SVt_NV, FALSE, HADNV, HASARENA, FIT_ARENA(0, sizeof(NV)) },
5b306eef 951#endif
d2a0f284 952
bc337e5c 953 { sizeof(XPV) - STRUCT_OFFSET(XPV, xpv_cur),
889d28b2
NC
954 copy_length(XPV, xpv_len) - STRUCT_OFFSET(XPV, xpv_cur),
955 + STRUCT_OFFSET(XPV, xpv_cur),
69ba284b 956 SVt_PV, FALSE, NONV, HASARENA,
889d28b2 957 FIT_ARENA(0, sizeof(XPV) - STRUCT_OFFSET(XPV, xpv_cur)) },
d2a0f284 958
d361b004
KW
959 { sizeof(XINVLIST) - STRUCT_OFFSET(XPV, xpv_cur),
960 copy_length(XINVLIST, is_offset) - STRUCT_OFFSET(XPV, xpv_cur),
961 + STRUCT_OFFSET(XPV, xpv_cur),
962 SVt_INVLIST, TRUE, NONV, HASARENA,
963 FIT_ARENA(0, sizeof(XINVLIST) - STRUCT_OFFSET(XPV, xpv_cur)) },
e94d9b54 964
bc337e5c 965 { sizeof(XPVIV) - STRUCT_OFFSET(XPV, xpv_cur),
889d28b2
NC
966 copy_length(XPVIV, xiv_u) - STRUCT_OFFSET(XPV, xpv_cur),
967 + STRUCT_OFFSET(XPV, xpv_cur),
968 SVt_PVIV, FALSE, NONV, HASARENA,
969 FIT_ARENA(0, sizeof(XPVIV) - STRUCT_OFFSET(XPV, xpv_cur)) },
d2a0f284 970
bc337e5c 971 { sizeof(XPVNV) - STRUCT_OFFSET(XPV, xpv_cur),
889d28b2
NC
972 copy_length(XPVNV, xnv_u) - STRUCT_OFFSET(XPV, xpv_cur),
973 + STRUCT_OFFSET(XPV, xpv_cur),
974 SVt_PVNV, FALSE, HADNV, HASARENA,
975 FIT_ARENA(0, sizeof(XPVNV) - STRUCT_OFFSET(XPV, xpv_cur)) },
d2a0f284 976
6e128786 977 { sizeof(XPVMG), copy_length(XPVMG, xnv_u), 0, SVt_PVMG, FALSE, HADNV,
d2a0f284 978 HASARENA, FIT_ARENA(0, sizeof(XPVMG)) },
4df7f6af 979
601dfd0a
NC
980 { sizeof(regexp),
981 sizeof(regexp),
982 0,
ecff11eb 983 SVt_REGEXP, TRUE, NONV, HASARENA,
eaeb1e7f 984 FIT_ARENA(0, sizeof(regexp))
5c35adbb 985 },
4df7f6af 986
10666ae3 987 { sizeof(XPVGV), sizeof(XPVGV), 0, SVt_PVGV, TRUE, HADNV,
d2a0f284
JC
988 HASARENA, FIT_ARENA(0, sizeof(XPVGV)) },
989
10666ae3 990 { sizeof(XPVLV), sizeof(XPVLV), 0, SVt_PVLV, TRUE, HADNV,
d2a0f284
JC
991 HASARENA, FIT_ARENA(0, sizeof(XPVLV)) },
992
601dfd0a 993 { sizeof(XPVAV),
4f7003f5 994 copy_length(XPVAV, xav_alloc),
601dfd0a 995 0,
69ba284b 996 SVt_PVAV, TRUE, NONV, HASARENA,
601dfd0a 997 FIT_ARENA(0, sizeof(XPVAV)) },
d2a0f284 998
601dfd0a 999 { sizeof(XPVHV),
359164a0 1000 copy_length(XPVHV, xhv_max),
601dfd0a 1001 0,
69ba284b 1002 SVt_PVHV, TRUE, NONV, HASARENA,
601dfd0a 1003 FIT_ARENA(0, sizeof(XPVHV)) },
d2a0f284 1004
601dfd0a
NC
1005 { sizeof(XPVCV),
1006 sizeof(XPVCV),
1007 0,
69ba284b 1008 SVt_PVCV, TRUE, NONV, HASARENA,
601dfd0a 1009 FIT_ARENA(0, sizeof(XPVCV)) },
69ba284b 1010
601dfd0a
NC
1011 { sizeof(XPVFM),
1012 sizeof(XPVFM),
1013 0,
69ba284b 1014 SVt_PVFM, TRUE, NONV, NOARENA,
601dfd0a 1015 FIT_ARENA(20, sizeof(XPVFM)) },
d2a0f284 1016
601dfd0a
NC
1017 { sizeof(XPVIO),
1018 sizeof(XPVIO),
1019 0,
b6f60916 1020 SVt_PVIO, TRUE, NONV, HASARENA,
601dfd0a 1021 FIT_ARENA(24, sizeof(XPVIO)) },
bd81e77b 1022};
29489e7c 1023
bd81e77b 1024#define new_body_allocated(sv_type) \
d2a0f284 1025 (void *)((char *)S_new_body(aTHX_ sv_type) \
bd81e77b 1026 - bodies_by_type[sv_type].offset)
29489e7c 1027
26359cfa
NC
1028/* return a thing to the free list */
1029
1030#define del_body(thing, root) \
1031 STMT_START { \
1032 void ** const thing_copy = (void **)thing; \
1033 *thing_copy = *root; \
1034 *root = (void*)thing_copy; \
1035 } STMT_END
29489e7c 1036
bd81e77b 1037#ifdef PURIFY
5b306eef
DD
1038#if !(NVSIZE <= IVSIZE)
1039# define new_XNV() safemalloc(sizeof(XPVNV))
1040#endif
beeec492
NC
1041#define new_XPVNV() safemalloc(sizeof(XPVNV))
1042#define new_XPVMG() safemalloc(sizeof(XPVMG))
29489e7c 1043
beeec492 1044#define del_XPVGV(p) safefree(p)
29489e7c 1045
bd81e77b 1046#else /* !PURIFY */
29489e7c 1047
5b306eef
DD
1048#if !(NVSIZE <= IVSIZE)
1049# define new_XNV() new_body_allocated(SVt_NV)
1050#endif
65ac1738 1051#define new_XPVNV() new_body_allocated(SVt_PVNV)
65ac1738 1052#define new_XPVMG() new_body_allocated(SVt_PVMG)
645c22ef 1053
26359cfa
NC
1054#define del_XPVGV(p) del_body(p + bodies_by_type[SVt_PVGV].offset, \
1055 &PL_body_roots[SVt_PVGV])
1d7c1841 1056
bd81e77b 1057#endif /* PURIFY */
93e68bfb 1058
bd81e77b 1059/* no arena for you! */
93e68bfb 1060
bd81e77b 1061#define new_NOARENA(details) \
beeec492 1062 safemalloc((details)->body_size + (details)->offset)
bd81e77b 1063#define new_NOARENAZ(details) \
beeec492 1064 safecalloc((details)->body_size + (details)->offset, 1)
d2a0f284 1065
1e30fcd5
NC
1066void *
1067Perl_more_bodies (pTHX_ const svtype sv_type, const size_t body_size,
1068 const size_t arena_size)
d2a0f284 1069{
d2a0f284 1070 void ** const root = &PL_body_roots[sv_type];
99816f8d
NC
1071 struct arena_desc *adesc;
1072 struct arena_set *aroot = (struct arena_set *) PL_body_arenas;
1073 unsigned int curr;
d2a0f284
JC
1074 char *start;
1075 const char *end;
02982131 1076 const size_t good_arena_size = Perl_malloc_good_size(arena_size);
20b7effb
JH
1077#if defined(DEBUGGING) && defined(PERL_GLOBAL_STRUCT)
1078 dVAR;
1079#endif
0b2d3faa 1080#if defined(DEBUGGING) && !defined(PERL_GLOBAL_STRUCT_PRIVATE)
23e9d66c
NC
1081 static bool done_sanity_check;
1082
0b2d3faa
JH
1083 /* PERL_GLOBAL_STRUCT_PRIVATE cannot coexist with global
1084 * variables like done_sanity_check. */
10666ae3 1085 if (!done_sanity_check) {
ea471437 1086 unsigned int i = SVt_LAST;
10666ae3
NC
1087
1088 done_sanity_check = TRUE;
1089
1090 while (i--)
1091 assert (bodies_by_type[i].type == i);
1092 }
1093#endif
1094
02982131 1095 assert(arena_size);
23e9d66c 1096
99816f8d
NC
1097 /* may need new arena-set to hold new arena */
1098 if (!aroot || aroot->curr >= aroot->set_size) {
1099 struct arena_set *newroot;
1100 Newxz(newroot, 1, struct arena_set);
1101 newroot->set_size = ARENAS_PER_SET;
1102 newroot->next = aroot;
1103 aroot = newroot;
1104 PL_body_arenas = (void *) newroot;
1105 DEBUG_m(PerlIO_printf(Perl_debug_log, "new arenaset %p\n", (void*)aroot));
1106 }
1107
1108 /* ok, now have arena-set with at least 1 empty/available arena-desc */
1109 curr = aroot->curr++;
1110 adesc = &(aroot->set[curr]);
1111 assert(!adesc->arena);
1112
1113 Newx(adesc->arena, good_arena_size, char);
1114 adesc->size = good_arena_size;
1115 adesc->utype = sv_type;
1116 DEBUG_m(PerlIO_printf(Perl_debug_log, "arena %d added: %p size %"UVuf"\n",
1117 curr, (void*)adesc->arena, (UV)good_arena_size));
1118
1119 start = (char *) adesc->arena;
d2a0f284 1120
29657bb6
NC
1121 /* Get the address of the byte after the end of the last body we can fit.
1122 Remember, this is integer division: */
02982131 1123 end = start + good_arena_size / body_size * body_size;
d2a0f284 1124
486ec47a 1125 /* computed count doesn't reflect the 1st slot reservation */
d8fca402
NC
1126#if defined(MYMALLOC) || defined(HAS_MALLOC_GOOD_SIZE)
1127 DEBUG_m(PerlIO_printf(Perl_debug_log,
1128 "arena %p end %p arena-size %d (from %d) type %d "
1129 "size %d ct %d\n",
02982131
NC
1130 (void*)start, (void*)end, (int)good_arena_size,
1131 (int)arena_size, sv_type, (int)body_size,
1132 (int)good_arena_size / (int)body_size));
d8fca402 1133#else
d2a0f284
JC
1134 DEBUG_m(PerlIO_printf(Perl_debug_log,
1135 "arena %p end %p arena-size %d type %d size %d ct %d\n",
6c9570dc 1136 (void*)start, (void*)end,
02982131
NC
1137 (int)arena_size, sv_type, (int)body_size,
1138 (int)good_arena_size / (int)body_size));
d8fca402 1139#endif
d2a0f284
JC
1140 *root = (void *)start;
1141
29657bb6
NC
1142 while (1) {
1143 /* Where the next body would start: */
d2a0f284 1144 char * const next = start + body_size;
29657bb6
NC
1145
1146 if (next >= end) {
1147 /* This is the last body: */
1148 assert(next == end);
1149
1150 *(void **)start = 0;
1151 return *root;
1152 }
1153
d2a0f284
JC
1154 *(void**) start = (void *)next;
1155 start = next;
1156 }
d2a0f284
JC
1157}
1158
1159/* grab a new thing from the free list, allocating more if necessary.
1160 The inline version is used for speed in hot routines, and the
1161 function using it serves the rest (unless PURIFY).
1162*/
1163#define new_body_inline(xpv, sv_type) \
1164 STMT_START { \
1165 void ** const r3wt = &PL_body_roots[sv_type]; \
11b79775 1166 xpv = (PTR_TBL_ENT_t*) (*((void **)(r3wt)) \
1e30fcd5 1167 ? *((void **)(r3wt)) : Perl_more_bodies(aTHX_ sv_type, \
02982131
NC
1168 bodies_by_type[sv_type].body_size,\
1169 bodies_by_type[sv_type].arena_size)); \
d2a0f284 1170 *(r3wt) = *(void**)(xpv); \
d2a0f284
JC
1171 } STMT_END
1172
1173#ifndef PURIFY
1174
1175STATIC void *
de37a194 1176S_new_body(pTHX_ const svtype sv_type)
d2a0f284 1177{
d2a0f284
JC
1178 void *xpv;
1179 new_body_inline(xpv, sv_type);
1180 return xpv;
1181}
1182
1183#endif
93e68bfb 1184
238b27b3
NC
1185static const struct body_details fake_rv =
1186 { 0, 0, 0, SVt_IV, FALSE, NONV, NOARENA, 0 };
1187
bd81e77b
NC
1188/*
1189=for apidoc sv_upgrade
93e68bfb 1190
bd81e77b
NC
1191Upgrade an SV to a more complex form. Generally adds a new body type to the
1192SV, then copies across as much information as possible from the old body.
9521ca61
FC
1193It croaks if the SV is already in a more complex form than requested. You
1194generally want to use the C<SvUPGRADE> macro wrapper, which checks the type
1195before calling C<sv_upgrade>, and hence does not croak. See also
1196C<svtype>.
93e68bfb 1197
bd81e77b 1198=cut
93e68bfb 1199*/
93e68bfb 1200
bd81e77b 1201void
5aaab254 1202Perl_sv_upgrade(pTHX_ SV *const sv, svtype new_type)
cac9b346 1203{
bd81e77b
NC
1204 void* old_body;
1205 void* new_body;
42d0e0b7 1206 const svtype old_type = SvTYPE(sv);
d2a0f284 1207 const struct body_details *new_type_details;
238b27b3 1208 const struct body_details *old_type_details
bd81e77b 1209 = bodies_by_type + old_type;
4df7f6af 1210 SV *referant = NULL;
cac9b346 1211
7918f24d
NC
1212 PERL_ARGS_ASSERT_SV_UPGRADE;
1213
1776cbe8
NC
1214 if (old_type == new_type)
1215 return;
1216
1217 /* This clause was purposefully added ahead of the early return above to
1218 the shared string hackery for (sort {$a <=> $b} keys %hash), with the
1219 inference by Nick I-S that it would fix other troublesome cases. See
1220 changes 7162, 7163 (f130fd4589cf5fbb24149cd4db4137c8326f49c1 and parent)
1221
1222 Given that shared hash key scalars are no longer PVIV, but PV, there is
1223 no longer need to unshare so as to free up the IVX slot for its proper
1224 purpose. So it's safe to move the early return earlier. */
1225
093085a8 1226 if (new_type > SVt_PVMG && SvIsCOW(sv)) {
bd81e77b
NC
1227 sv_force_normal_flags(sv, 0);
1228 }
cac9b346 1229
bd81e77b 1230 old_body = SvANY(sv);
de042e1d 1231
bd81e77b
NC
1232 /* Copying structures onto other structures that have been neatly zeroed
1233 has a subtle gotcha. Consider XPVMG
cac9b346 1234
bd81e77b
NC
1235 +------+------+------+------+------+-------+-------+
1236 | NV | CUR | LEN | IV | MAGIC | STASH |
1237 +------+------+------+------+------+-------+-------+
1238 0 4 8 12 16 20 24 28
645c22ef 1239
bd81e77b
NC
1240 where NVs are aligned to 8 bytes, so that sizeof that structure is
1241 actually 32 bytes long, with 4 bytes of padding at the end:
08742458 1242
bd81e77b
NC
1243 +------+------+------+------+------+-------+-------+------+
1244 | NV | CUR | LEN | IV | MAGIC | STASH | ??? |
1245 +------+------+------+------+------+-------+-------+------+
1246 0 4 8 12 16 20 24 28 32
08742458 1247
bd81e77b 1248 so what happens if you allocate memory for this structure:
30f9da9e 1249
bd81e77b
NC
1250 +------+------+------+------+------+-------+-------+------+------+...
1251 | NV | CUR | LEN | IV | MAGIC | STASH | GP | NAME |
1252 +------+------+------+------+------+-------+-------+------+------+...
1253 0 4 8 12 16 20 24 28 32 36
bfc44f79 1254
bd81e77b
NC
1255 zero it, then copy sizeof(XPVMG) bytes on top of it? Not quite what you
1256 expect, because you copy the area marked ??? onto GP. Now, ??? may have
1257 started out as zero once, but it's quite possible that it isn't. So now,
1258 rather than a nicely zeroed GP, you have it pointing somewhere random.
1259 Bugs ensue.
bfc44f79 1260
bd81e77b
NC
1261 (In fact, GP ends up pointing at a previous GP structure, because the
1262 principle cause of the padding in XPVMG getting garbage is a copy of
6c9e42f7
NC
1263 sizeof(XPVMG) bytes from a XPVGV structure in sv_unglob. Right now
1264 this happens to be moot because XPVGV has been re-ordered, with GP
1265 no longer after STASH)
30f9da9e 1266
bd81e77b
NC
1267 So we are careful and work out the size of used parts of all the
1268 structures. */
bfc44f79 1269
bd81e77b
NC
1270 switch (old_type) {
1271 case SVt_NULL:
1272 break;
1273 case SVt_IV:
4df7f6af
NC
1274 if (SvROK(sv)) {
1275 referant = SvRV(sv);
238b27b3
NC
1276 old_type_details = &fake_rv;
1277 if (new_type == SVt_NV)
1278 new_type = SVt_PVNV;
4df7f6af
NC
1279 } else {
1280 if (new_type < SVt_PVIV) {
1281 new_type = (new_type == SVt_NV)
1282 ? SVt_PVNV : SVt_PVIV;
1283 }
bd81e77b
NC
1284 }
1285 break;
1286 case SVt_NV:
1287 if (new_type < SVt_PVNV) {
1288 new_type = SVt_PVNV;
bd81e77b
NC
1289 }
1290 break;
bd81e77b
NC
1291 case SVt_PV:
1292 assert(new_type > SVt_PV);
1293 assert(SVt_IV < SVt_PV);
1294 assert(SVt_NV < SVt_PV);
1295 break;
1296 case SVt_PVIV:
1297 break;
1298 case SVt_PVNV:
1299 break;
1300 case SVt_PVMG:
1301 /* Because the XPVMG of PL_mess_sv isn't allocated from the arena,
1302 there's no way that it can be safely upgraded, because perl.c
1303 expects to Safefree(SvANY(PL_mess_sv)) */
1304 assert(sv != PL_mess_sv);
1305 /* This flag bit is used to mean other things in other scalar types.
1306 Given that it only has meaning inside the pad, it shouldn't be set
1307 on anything that can get upgraded. */
00b1698f 1308 assert(!SvPAD_TYPED(sv));
bd81e77b
NC
1309 break;
1310 default:
2439e033 1311 if (UNLIKELY(old_type_details->cant_upgrade))
c81225bc
NC
1312 Perl_croak(aTHX_ "Can't upgrade %s (%" UVuf ") to %" UVuf,
1313 sv_reftype(sv, 0), (UV) old_type, (UV) new_type);
bd81e77b 1314 }
3376de98 1315
2439e033 1316 if (UNLIKELY(old_type > new_type))
3376de98
NC
1317 Perl_croak(aTHX_ "sv_upgrade from type %d down to type %d",
1318 (int)old_type, (int)new_type);
1319
2fa1109b 1320 new_type_details = bodies_by_type + new_type;
645c22ef 1321
bd81e77b
NC
1322 SvFLAGS(sv) &= ~SVTYPEMASK;
1323 SvFLAGS(sv) |= new_type;
932e9ff9 1324
ab4416c0
NC
1325 /* This can't happen, as SVt_NULL is <= all values of new_type, so one of
1326 the return statements above will have triggered. */
1327 assert (new_type != SVt_NULL);
bd81e77b 1328 switch (new_type) {
bd81e77b
NC
1329 case SVt_IV:
1330 assert(old_type == SVt_NULL);
1331 SvANY(sv) = (XPVIV*)((char*)&(sv->sv_u.svu_iv) - STRUCT_OFFSET(XPVIV, xiv_iv));
1332 SvIV_set(sv, 0);
1333 return;
1334 case SVt_NV:
1335 assert(old_type == SVt_NULL);
5b306eef
DD
1336#if NVSIZE <= IVSIZE
1337 SvANY(sv) = (XPVNV*)((char*)&(sv->sv_u.svu_nv) - STRUCT_OFFSET(XPVNV, xnv_u.xnv_nv));
1338#else
bd81e77b 1339 SvANY(sv) = new_XNV();
5b306eef 1340#endif
bd81e77b
NC
1341 SvNV_set(sv, 0);
1342 return;
bd81e77b 1343 case SVt_PVHV:
bd81e77b 1344 case SVt_PVAV:
d2a0f284 1345 assert(new_type_details->body_size);
c1ae03ae
NC
1346
1347#ifndef PURIFY
1348 assert(new_type_details->arena);
d2a0f284 1349 assert(new_type_details->arena_size);
c1ae03ae 1350 /* This points to the start of the allocated area. */
d2a0f284
JC
1351 new_body_inline(new_body, new_type);
1352 Zero(new_body, new_type_details->body_size, char);
c1ae03ae
NC
1353 new_body = ((char *)new_body) - new_type_details->offset;
1354#else
1355 /* We always allocated the full length item with PURIFY. To do this
1356 we fake things so that arena is false for all 16 types.. */
1357 new_body = new_NOARENAZ(new_type_details);
1358#endif
1359 SvANY(sv) = new_body;
1360 if (new_type == SVt_PVAV) {
1361 AvMAX(sv) = -1;
1362 AvFILLp(sv) = -1;
1363 AvREAL_only(sv);
64484faa 1364 if (old_type_details->body_size) {
ac572bf4
NC
1365 AvALLOC(sv) = 0;
1366 } else {
1367 /* It will have been zeroed when the new body was allocated.
1368 Lets not write to it, in case it confuses a write-back
1369 cache. */
1370 }
78ac7dd9
NC
1371 } else {
1372 assert(!SvOK(sv));
1373 SvOK_off(sv);
1374#ifndef NODEFAULT_SHAREKEYS
1375 HvSHAREKEYS_on(sv); /* key-sharing on by default */
1376#endif
586fc6a3
SM
1377 /* start with PERL_HASH_DEFAULT_HvMAX+1 buckets: */
1378 HvMAX(sv) = PERL_HASH_DEFAULT_HvMAX;
c1ae03ae 1379 }
aeb18a1e 1380
bd81e77b
NC
1381 /* SVt_NULL isn't the only thing upgraded to AV or HV.
1382 The target created by newSVrv also is, and it can have magic.
1383 However, it never has SvPVX set.
1384 */
4df7f6af
NC
1385 if (old_type == SVt_IV) {
1386 assert(!SvROK(sv));
1387 } else if (old_type >= SVt_PV) {
bd81e77b
NC
1388 assert(SvPVX_const(sv) == 0);
1389 }
aeb18a1e 1390
bd81e77b 1391 if (old_type >= SVt_PVMG) {
e736a858 1392 SvMAGIC_set(sv, ((XPVMG*)old_body)->xmg_u.xmg_magic);
bd81e77b 1393 SvSTASH_set(sv, ((XPVMG*)old_body)->xmg_stash);
797c7171
NC
1394 } else {
1395 sv->sv_u.svu_array = NULL; /* or svu_hash */
bd81e77b
NC
1396 }
1397 break;
93e68bfb 1398
bd81e77b
NC
1399 case SVt_PVIV:
1400 /* XXX Is this still needed? Was it ever needed? Surely as there is
1401 no route from NV to PVIV, NOK can never be true */
1402 assert(!SvNOKp(sv));
1403 assert(!SvNOK(sv));
1404 case SVt_PVIO:
1405 case SVt_PVFM:
bd81e77b
NC
1406 case SVt_PVGV:
1407 case SVt_PVCV:
1408 case SVt_PVLV:
d361b004 1409 case SVt_INVLIST:
12c45b25 1410 case SVt_REGEXP:
bd81e77b
NC
1411 case SVt_PVMG:
1412 case SVt_PVNV:
1413 case SVt_PV:
93e68bfb 1414
d2a0f284 1415 assert(new_type_details->body_size);
bd81e77b
NC
1416 /* We always allocated the full length item with PURIFY. To do this
1417 we fake things so that arena is false for all 16 types.. */
1418 if(new_type_details->arena) {
1419 /* This points to the start of the allocated area. */
d2a0f284
JC
1420 new_body_inline(new_body, new_type);
1421 Zero(new_body, new_type_details->body_size, char);
bd81e77b
NC
1422 new_body = ((char *)new_body) - new_type_details->offset;
1423 } else {
1424 new_body = new_NOARENAZ(new_type_details);
1425 }
1426 SvANY(sv) = new_body;
5e2fc214 1427
bd81e77b 1428 if (old_type_details->copy) {
f9ba3d20
NC
1429 /* There is now the potential for an upgrade from something without
1430 an offset (PVNV or PVMG) to something with one (PVCV, PVFM) */
1431 int offset = old_type_details->offset;
1432 int length = old_type_details->copy;
1433
1434 if (new_type_details->offset > old_type_details->offset) {
d4c19fe8 1435 const int difference
f9ba3d20
NC
1436 = new_type_details->offset - old_type_details->offset;
1437 offset += difference;
1438 length -= difference;
1439 }
1440 assert (length >= 0);
1441
1442 Copy((char *)old_body + offset, (char *)new_body + offset, length,
1443 char);
bd81e77b
NC
1444 }
1445
1446#ifndef NV_ZERO_IS_ALLBITS_ZERO
f2524eef 1447 /* If NV 0.0 is stores as all bits 0 then Zero() already creates a
e5ce394c
NC
1448 * correct 0.0 for us. Otherwise, if the old body didn't have an
1449 * NV slot, but the new one does, then we need to initialise the
1450 * freshly created NV slot with whatever the correct bit pattern is
1451 * for 0.0 */
e22a937e
NC
1452 if (old_type_details->zero_nv && !new_type_details->zero_nv
1453 && !isGV_with_GP(sv))
bd81e77b 1454 SvNV_set(sv, 0);
82048762 1455#endif
5e2fc214 1456
2439e033 1457 if (UNLIKELY(new_type == SVt_PVIO)) {
85dca89a 1458 IO * const io = MUTABLE_IO(sv);
d963bf01 1459 GV *iogv = gv_fetchpvs("IO::File::", GV_ADD, SVt_PVHV);
85dca89a
NC
1460
1461 SvOBJECT_on(io);
1462 /* Clear the stashcache because a new IO could overrule a package
1463 name */
103f5a36 1464 DEBUG_o(Perl_deb(aTHX_ "sv_upgrade clearing PL_stashcache\n"));
85dca89a
NC
1465 hv_clear(PL_stashcache);
1466
85dca89a 1467 SvSTASH_set(io, MUTABLE_HV(SvREFCNT_inc(GvHV(iogv))));
f2524eef 1468 IoPAGE_LEN(sv) = 60;
85dca89a 1469 }
2439e033 1470 if (UNLIKELY(new_type == SVt_REGEXP))
8d919b0a
FC
1471 sv->sv_u.svu_rx = (regexp *)new_body;
1472 else if (old_type < SVt_PV) {
4df7f6af
NC
1473 /* referant will be NULL unless the old type was SVt_IV emulating
1474 SVt_RV */
1475 sv->sv_u.svu_rv = referant;
1476 }
bd81e77b
NC
1477 break;
1478 default:
afd78fd5
JH
1479 Perl_croak(aTHX_ "panic: sv_upgrade to unknown type %lu",
1480 (unsigned long)new_type);
bd81e77b 1481 }
73171d91 1482
5b306eef
DD
1483 /* if this is zero, this is a body-less SVt_NULL, SVt_IV/SVt_RV,
1484 and sometimes SVt_NV */
1485 if (old_type_details->body_size) {
bd81e77b 1486#ifdef PURIFY
beeec492 1487 safefree(old_body);
bd81e77b 1488#else
bc786448
GG
1489 /* Note that there is an assumption that all bodies of types that
1490 can be upgraded came from arenas. Only the more complex non-
1491 upgradable types are allowed to be directly malloc()ed. */
1492 assert(old_type_details->arena);
bd81e77b
NC
1493 del_body((void*)((char*)old_body + old_type_details->offset),
1494 &PL_body_roots[old_type]);
1495#endif
1496 }
1497}
73171d91 1498
bd81e77b
NC
1499/*
1500=for apidoc sv_backoff
73171d91 1501
fde67290 1502Remove any string offset. You should normally use the C<SvOOK_off> macro
bd81e77b 1503wrapper instead.
73171d91 1504
bd81e77b 1505=cut
73171d91
NC
1506*/
1507
bd81e77b 1508int
ddeaf645 1509Perl_sv_backoff(SV *const sv)
bd81e77b 1510{
69240efd 1511 STRLEN delta;
7a4bba22 1512 const char * const s = SvPVX_const(sv);
7918f24d
NC
1513
1514 PERL_ARGS_ASSERT_SV_BACKOFF;
7918f24d 1515
bd81e77b
NC
1516 assert(SvOOK(sv));
1517 assert(SvTYPE(sv) != SVt_PVHV);
1518 assert(SvTYPE(sv) != SVt_PVAV);
7a4bba22 1519
69240efd
NC
1520 SvOOK_offset(sv, delta);
1521
7a4bba22
NC
1522 SvLEN_set(sv, SvLEN(sv) + delta);
1523 SvPV_set(sv, SvPVX(sv) - delta);
1524 Move(s, SvPVX(sv), SvCUR(sv)+1, char);
bd81e77b
NC
1525 SvFLAGS(sv) &= ~SVf_OOK;
1526 return 0;
1527}
73171d91 1528
bd81e77b
NC
1529/*
1530=for apidoc sv_grow
73171d91 1531
bd81e77b
NC
1532Expands the character buffer in the SV. If necessary, uses C<sv_unref> and
1533upgrades the SV to C<SVt_PV>. Returns a pointer to the character buffer.
1534Use the C<SvGROW> wrapper instead.
93e68bfb 1535
bd81e77b
NC
1536=cut
1537*/
93e68bfb 1538
e0060e30
FC
1539static void S_sv_uncow(pTHX_ SV * const sv, const U32 flags);
1540
bd81e77b 1541char *
5aaab254 1542Perl_sv_grow(pTHX_ SV *const sv, STRLEN newlen)
bd81e77b 1543{
eb578fdb 1544 char *s;
93e68bfb 1545
7918f24d
NC
1546 PERL_ARGS_ASSERT_SV_GROW;
1547
bd81e77b
NC
1548 if (SvROK(sv))
1549 sv_unref(sv);
1550 if (SvTYPE(sv) < SVt_PV) {
1551 sv_upgrade(sv, SVt_PV);
1552 s = SvPVX_mutable(sv);
1553 }
1554 else if (SvOOK(sv)) { /* pv is offset? */
1555 sv_backoff(sv);
1556 s = SvPVX_mutable(sv);
1557 if (newlen > SvLEN(sv))
1558 newlen += 10 * (newlen - SvCUR(sv)); /* avoid copy each time */
bd81e77b
NC
1559 }
1560 else
db2c6cb3 1561 {
e0060e30 1562 if (SvIsCOW(sv)) S_sv_uncow(aTHX_ sv, 0);
bd81e77b 1563 s = SvPVX_mutable(sv);
db2c6cb3 1564 }
aeb18a1e 1565
cbcb2a16
DM
1566#ifdef PERL_NEW_COPY_ON_WRITE
1567 /* the new COW scheme uses SvPVX(sv)[SvLEN(sv)-1] (if spare)
3c239bea 1568 * to store the COW count. So in general, allocate one more byte than
cbcb2a16
DM
1569 * asked for, to make it likely this byte is always spare: and thus
1570 * make more strings COW-able.
1571 * If the new size is a big power of two, don't bother: we assume the
1572 * caller wanted a nice 2^N sized block and will be annoyed at getting
1573 * 2^N+1 */
1574 if (newlen & 0xff)
1575 newlen++;
1576#endif
1577
ce861ea7
YO
1578#if defined(PERL_USE_MALLOC_SIZE) && defined(Perl_safesysmalloc_size)
1579#define PERL_UNWARANTED_CHUMMINESS_WITH_MALLOC
1580#endif
1581
bd81e77b 1582 if (newlen > SvLEN(sv)) { /* need more room? */
f1200559 1583 STRLEN minlen = SvCUR(sv);
3c239bea 1584 minlen += (minlen >> PERL_STRLEN_EXPAND_SHIFT) + 10;
f1200559
WH
1585 if (newlen < minlen)
1586 newlen = minlen;
ce861ea7 1587#ifndef PERL_UNWARANTED_CHUMMINESS_WITH_MALLOC
7c641603
KW
1588
1589 /* Don't round up on the first allocation, as odds are pretty good that
1590 * the initial request is accurate as to what is really needed */
ce861ea7 1591 if (SvLEN(sv)) {
e8c6a474 1592 newlen = PERL_STRLEN_ROUNDUP(newlen);
ce861ea7 1593 }
bd81e77b 1594#endif
98653f18 1595 if (SvLEN(sv) && s) {
10edeb5d 1596 s = (char*)saferealloc(s, newlen);
bd81e77b
NC
1597 }
1598 else {
10edeb5d 1599 s = (char*)safemalloc(newlen);
bd81e77b
NC
1600 if (SvPVX_const(sv) && SvCUR(sv)) {
1601 Move(SvPVX_const(sv), s, (newlen < SvCUR(sv)) ? newlen : SvCUR(sv), char);
1602 }
1603 }
1604 SvPV_set(sv, s);
ce861ea7 1605#ifdef PERL_UNWARANTED_CHUMMINESS_WITH_MALLOC
98653f18
NC
1606 /* Do this here, do it once, do it right, and then we will never get
1607 called back into sv_grow() unless there really is some growing
1608 needed. */
ca7c1a29 1609 SvLEN_set(sv, Perl_safesysmalloc_size(s));
98653f18 1610#else
bd81e77b 1611 SvLEN_set(sv, newlen);
98653f18 1612#endif
bd81e77b
NC
1613 }
1614 return s;
1615}
aeb18a1e 1616
bd81e77b
NC
1617/*
1618=for apidoc sv_setiv
932e9ff9 1619
bd81e77b
NC
1620Copies an integer into the given SV, upgrading first if necessary.
1621Does not handle 'set' magic. See also C<sv_setiv_mg>.
463ee0b2 1622
bd81e77b
NC
1623=cut
1624*/
463ee0b2 1625
bd81e77b 1626void
5aaab254 1627Perl_sv_setiv(pTHX_ SV *const sv, const IV i)
bd81e77b 1628{
7918f24d
NC
1629 PERL_ARGS_ASSERT_SV_SETIV;
1630
bd81e77b
NC
1631 SV_CHECK_THINKFIRST_COW_DROP(sv);
1632 switch (SvTYPE(sv)) {
1633 case SVt_NULL:
bd81e77b 1634 case SVt_NV:
3376de98 1635 sv_upgrade(sv, SVt_IV);
bd81e77b 1636 break;
bd81e77b
NC
1637 case SVt_PV:
1638 sv_upgrade(sv, SVt_PVIV);
1639 break;
463ee0b2 1640
bd81e77b 1641 case SVt_PVGV:
6e592b3a
BM
1642 if (!isGV_with_GP(sv))
1643 break;
bd81e77b
NC
1644 case SVt_PVAV:
1645 case SVt_PVHV:
1646 case SVt_PVCV:
1647 case SVt_PVFM:
1648 case SVt_PVIO:
22e74366 1649 /* diag_listed_as: Can't coerce %s to %s in %s */
bd81e77b
NC
1650 Perl_croak(aTHX_ "Can't coerce %s to integer in %s", sv_reftype(sv,0),
1651 OP_DESC(PL_op));
42d0e0b7 1652 default: NOOP;
bd81e77b
NC
1653 }
1654 (void)SvIOK_only(sv); /* validate number */
1655 SvIV_set(sv, i);
1656 SvTAINT(sv);
1657}
932e9ff9 1658
bd81e77b
NC
1659/*
1660=for apidoc sv_setiv_mg
d33b2eba 1661
bd81e77b 1662Like C<sv_setiv>, but also handles 'set' magic.
1c846c1f 1663
bd81e77b
NC
1664=cut
1665*/
d33b2eba 1666
bd81e77b 1667void
5aaab254 1668Perl_sv_setiv_mg(pTHX_ SV *const sv, const IV i)
bd81e77b 1669{
7918f24d
NC
1670 PERL_ARGS_ASSERT_SV_SETIV_MG;
1671
bd81e77b
NC
1672 sv_setiv(sv,i);
1673 SvSETMAGIC(sv);
1674}
727879eb 1675
bd81e77b
NC
1676/*
1677=for apidoc sv_setuv
d33b2eba 1678
bd81e77b
NC
1679Copies an unsigned integer into the given SV, upgrading first if necessary.
1680Does not handle 'set' magic. See also C<sv_setuv_mg>.
9b94d1dd 1681
bd81e77b
NC
1682=cut
1683*/
d33b2eba 1684
bd81e77b 1685void
5aaab254 1686Perl_sv_setuv(pTHX_ SV *const sv, const UV u)
bd81e77b 1687{
7918f24d
NC
1688 PERL_ARGS_ASSERT_SV_SETUV;
1689
013abb9b
NC
1690 /* With the if statement to ensure that integers are stored as IVs whenever
1691 possible:
bd81e77b 1692 u=1.49 s=0.52 cu=72.49 cs=10.64 scripts=270 tests=20865
d33b2eba 1693
bd81e77b
NC
1694 without
1695 u=1.35 s=0.47 cu=73.45 cs=11.43 scripts=270 tests=20865
1c846c1f 1696
013abb9b
NC
1697 If you wish to remove the following if statement, so that this routine
1698 (and its callers) always return UVs, please benchmark to see what the
1699 effect is. Modern CPUs may be different. Or may not :-)
bd81e77b
NC
1700 */
1701 if (u <= (UV)IV_MAX) {
1702 sv_setiv(sv, (IV)u);
1703 return;
1704 }
1705 sv_setiv(sv, 0);
1706 SvIsUV_on(sv);
1707 SvUV_set(sv, u);
1708}
d33b2eba 1709
bd81e77b
NC
1710/*
1711=for apidoc sv_setuv_mg
727879eb 1712
bd81e77b 1713Like C<sv_setuv>, but also handles 'set' magic.
9b94d1dd 1714
bd81e77b
NC
1715=cut
1716*/
5e2fc214 1717
bd81e77b 1718void
5aaab254 1719Perl_sv_setuv_mg(pTHX_ SV *const sv, const UV u)
bd81e77b 1720{
7918f24d
NC
1721 PERL_ARGS_ASSERT_SV_SETUV_MG;
1722
bd81e77b
NC
1723 sv_setuv(sv,u);
1724 SvSETMAGIC(sv);
1725}
5e2fc214 1726
954c1994 1727/*
bd81e77b 1728=for apidoc sv_setnv
954c1994 1729
bd81e77b
NC
1730Copies a double into the given SV, upgrading first if necessary.
1731Does not handle 'set' magic. See also C<sv_setnv_mg>.
954c1994
GS
1732
1733=cut
1734*/
1735
63f97190 1736void
5aaab254 1737Perl_sv_setnv(pTHX_ SV *const sv, const NV num)
79072805 1738{
7918f24d
NC
1739 PERL_ARGS_ASSERT_SV_SETNV;
1740
bd81e77b
NC
1741 SV_CHECK_THINKFIRST_COW_DROP(sv);
1742 switch (SvTYPE(sv)) {
79072805 1743 case SVt_NULL:
79072805 1744 case SVt_IV:
bd81e77b 1745 sv_upgrade(sv, SVt_NV);
79072805
LW
1746 break;
1747 case SVt_PV:
79072805 1748 case SVt_PVIV:
bd81e77b 1749 sv_upgrade(sv, SVt_PVNV);
79072805 1750 break;
bd4b1eb5 1751
bd4b1eb5 1752 case SVt_PVGV:
6e592b3a
BM
1753 if (!isGV_with_GP(sv))
1754 break;
bd81e77b
NC
1755 case SVt_PVAV:
1756 case SVt_PVHV:
79072805 1757 case SVt_PVCV:
bd81e77b
NC
1758 case SVt_PVFM:
1759 case SVt_PVIO:
22e74366 1760 /* diag_listed_as: Can't coerce %s to %s in %s */
bd81e77b 1761 Perl_croak(aTHX_ "Can't coerce %s to number in %s", sv_reftype(sv,0),
94bbb3f4 1762 OP_DESC(PL_op));
42d0e0b7 1763 default: NOOP;
2068cd4d 1764 }
bd81e77b
NC
1765 SvNV_set(sv, num);
1766 (void)SvNOK_only(sv); /* validate number */
1767 SvTAINT(sv);
79072805
LW
1768}
1769
645c22ef 1770/*
bd81e77b 1771=for apidoc sv_setnv_mg
645c22ef 1772
bd81e77b 1773Like C<sv_setnv>, but also handles 'set' magic.
645c22ef
DM
1774
1775=cut
1776*/
1777
bd81e77b 1778void
5aaab254 1779Perl_sv_setnv_mg(pTHX_ SV *const sv, const NV num)
79072805 1780{
7918f24d
NC
1781 PERL_ARGS_ASSERT_SV_SETNV_MG;
1782
bd81e77b
NC
1783 sv_setnv(sv,num);
1784 SvSETMAGIC(sv);
79072805
LW
1785}
1786
3f7602fa
TC
1787/* Return a cleaned-up, printable version of sv, for non-numeric, or
1788 * not incrementable warning display.
1789 * Originally part of S_not_a_number().
1790 * The return value may be != tmpbuf.
bd81e77b 1791 */
954c1994 1792
3f7602fa
TC
1793STATIC const char *
1794S_sv_display(pTHX_ SV *const sv, char *tmpbuf, STRLEN tmpbuf_size) {
1795 const char *pv;
94463019 1796
3f7602fa 1797 PERL_ARGS_ASSERT_SV_DISPLAY;
7918f24d 1798
94463019 1799 if (DO_UTF8(sv)) {
3f7602fa 1800 SV *dsv = newSVpvs_flags("", SVs_TEMP);
472394e4 1801 pv = sv_uni_display(dsv, sv, 10, UNI_DISPLAY_ISPRINT);
94463019
JH
1802 } else {
1803 char *d = tmpbuf;
3f7602fa 1804 const char * const limit = tmpbuf + tmpbuf_size - 8;
94463019
JH
1805 /* each *s can expand to 4 chars + "...\0",
1806 i.e. need room for 8 chars */
ecdeb87c 1807
00b6aa41
AL
1808 const char *s = SvPVX_const(sv);
1809 const char * const end = s + SvCUR(sv);
1810 for ( ; s < end && d < limit; s++ ) {
94463019 1811 int ch = *s & 0xFF;
bd27cf70 1812 if (! isASCII(ch) && !isPRINT_LC(ch)) {
94463019
JH
1813 *d++ = 'M';
1814 *d++ = '-';
bd27cf70
KW
1815
1816 /* Map to ASCII "equivalent" of Latin1 */
1817 ch = LATIN1_TO_NATIVE(NATIVE_TO_LATIN1(ch) & 127);
94463019
JH
1818 }
1819 if (ch == '\n') {
1820 *d++ = '\\';
1821 *d++ = 'n';
1822 }
1823 else if (ch == '\r') {
1824 *d++ = '\\';
1825 *d++ = 'r';
1826 }
1827 else if (ch == '\f') {
1828 *d++ = '\\';
1829 *d++ = 'f';
1830 }
1831 else if (ch == '\\') {
1832 *d++ = '\\';
1833 *d++ = '\\';
1834 }
1835 else if (ch == '\0') {
1836 *d++ = '\\';
1837 *d++ = '0';
1838 }
1839 else if (isPRINT_LC(ch))
1840 *d++ = ch;
1841 else {
1842 *d++ = '^';
1843 *d++ = toCTRL(ch);
1844 }
1845 }
1846 if (s < end) {
1847 *d++ = '.';
1848 *d++ = '.';
1849 *d++ = '.';
1850 }
1851 *d = '\0';
1852 pv = tmpbuf;
a0d0e21e 1853 }
a0d0e21e 1854
3f7602fa
TC
1855 return pv;
1856}
1857
1858/* Print an "isn't numeric" warning, using a cleaned-up,
1859 * printable version of the offending string
1860 */
1861
1862STATIC void
1863S_not_a_number(pTHX_ SV *const sv)
1864{
3f7602fa
TC
1865 char tmpbuf[64];
1866 const char *pv;
1867
1868 PERL_ARGS_ASSERT_NOT_A_NUMBER;
1869
1870 pv = sv_display(sv, tmpbuf, sizeof(tmpbuf));
1871
533c011a 1872 if (PL_op)
9014280d 1873 Perl_warner(aTHX_ packWARN(WARN_NUMERIC),
734856a2 1874 /* diag_listed_as: Argument "%s" isn't numeric%s */
94463019
JH
1875 "Argument \"%s\" isn't numeric in %s", pv,
1876 OP_DESC(PL_op));
a0d0e21e 1877 else
9014280d 1878 Perl_warner(aTHX_ packWARN(WARN_NUMERIC),
734856a2 1879 /* diag_listed_as: Argument "%s" isn't numeric%s */
94463019 1880 "Argument \"%s\" isn't numeric", pv);
a0d0e21e
LW
1881}
1882
3f7602fa
TC
1883STATIC void
1884S_not_incrementable(pTHX_ SV *const sv) {
3f7602fa
TC
1885 char tmpbuf[64];
1886 const char *pv;
1887
1888 PERL_ARGS_ASSERT_NOT_INCREMENTABLE;
1889
1890 pv = sv_display(sv, tmpbuf, sizeof(tmpbuf));
1891
1892 Perl_warner(aTHX_ packWARN(WARN_NUMERIC),
1893 "Argument \"%s\" treated as 0 in increment (++)", pv);
1894}
1895
c2988b20
NC
1896/*
1897=for apidoc looks_like_number
1898
645c22ef
DM
1899Test if the content of an SV looks like a number (or is a number).
1900C<Inf> and C<Infinity> are treated as numbers (so will not issue a
f52e41ad
FC
1901non-numeric warning), even if your atof() doesn't grok them. Get-magic is
1902ignored.
c2988b20
NC
1903
1904=cut
1905*/
1906
1907I32
aad570aa 1908Perl_looks_like_number(pTHX_ SV *const sv)
c2988b20 1909{
eb578fdb 1910 const char *sbegin;
c2988b20
NC
1911 STRLEN len;
1912
7918f24d
NC
1913 PERL_ARGS_ASSERT_LOOKS_LIKE_NUMBER;
1914
f52e41ad
FC
1915 if (SvPOK(sv) || SvPOKp(sv)) {
1916 sbegin = SvPV_nomg_const(sv, len);
c2988b20 1917 }
c2988b20 1918 else
e0ab1c0e 1919 return SvFLAGS(sv) & (SVf_NOK|SVp_NOK|SVf_IOK|SVp_IOK);
c2988b20
NC
1920 return grok_number(sbegin, len, NULL);
1921}
25da4f38 1922
19f6321d
NC
1923STATIC bool
1924S_glob_2number(pTHX_ GV * const gv)
180488f8 1925{
7918f24d
NC
1926 PERL_ARGS_ASSERT_GLOB_2NUMBER;
1927
675c862f
AL
1928 /* We know that all GVs stringify to something that is not-a-number,
1929 so no need to test that. */
1930 if (ckWARN(WARN_NUMERIC))
8e629ff4
FC
1931 {
1932 SV *const buffer = sv_newmortal();
1933 gv_efullname3(buffer, gv, "*");
675c862f 1934 not_a_number(buffer);
8e629ff4 1935 }
675c862f
AL
1936 /* We just want something true to return, so that S_sv_2iuv_common
1937 can tail call us and return true. */
19f6321d 1938 return TRUE;
675c862f
AL
1939}
1940
25da4f38
IZ
1941/* Actually, ISO C leaves conversion of UV to IV undefined, but
1942 until proven guilty, assume that things are not that bad... */
1943
645c22ef
DM
1944/*
1945 NV_PRESERVES_UV:
1946
1947 As 64 bit platforms often have an NV that doesn't preserve all bits of
28e5dec8
JH
1948 an IV (an assumption perl has been based on to date) it becomes necessary
1949 to remove the assumption that the NV always carries enough precision to
1950 recreate the IV whenever needed, and that the NV is the canonical form.
1951 Instead, IV/UV and NV need to be given equal rights. So as to not lose
645c22ef 1952 precision as a side effect of conversion (which would lead to insanity
28e5dec8 1953 and the dragon(s) in t/op/numconvert.t getting very angry) the intent is
8a4a3196
KW
1954 1) to distinguish between IV/UV/NV slots that have a valid conversion cached
1955 where precision was lost, and IV/UV/NV slots that have a valid conversion
1956 which has lost no precision
645c22ef 1957 2) to ensure that if a numeric conversion to one form is requested that
28e5dec8
JH
1958 would lose precision, the precise conversion (or differently
1959 imprecise conversion) is also performed and cached, to prevent
1960 requests for different numeric formats on the same SV causing
1961 lossy conversion chains. (lossless conversion chains are perfectly
1962 acceptable (still))
1963
1964
1965 flags are used:
1966 SvIOKp is true if the IV slot contains a valid value
1967 SvIOK is true only if the IV value is accurate (UV if SvIOK_UV true)
1968 SvNOKp is true if the NV slot contains a valid value
1969 SvNOK is true only if the NV value is accurate
1970
1971 so
645c22ef 1972 while converting from PV to NV, check to see if converting that NV to an
28e5dec8
JH
1973 IV(or UV) would lose accuracy over a direct conversion from PV to
1974 IV(or UV). If it would, cache both conversions, return NV, but mark
1975 SV as IOK NOKp (ie not NOK).
1976
645c22ef 1977 While converting from PV to IV, check to see if converting that IV to an
28e5dec8
JH
1978 NV would lose accuracy over a direct conversion from PV to NV. If it
1979 would, cache both conversions, flag similarly.
1980
1981 Before, the SV value "3.2" could become NV=3.2 IV=3 NOK, IOK quite
1982 correctly because if IV & NV were set NV *always* overruled.
645c22ef
DM
1983 Now, "3.2" will become NV=3.2 IV=3 NOK, IOKp, because the flag's meaning
1984 changes - now IV and NV together means that the two are interchangeable:
28e5dec8 1985 SvIVX == (IV) SvNVX && SvNVX == (NV) SvIVX;
d460ef45 1986
645c22ef
DM
1987 The benefit of this is that operations such as pp_add know that if
1988 SvIOK is true for both left and right operands, then integer addition
1989 can be used instead of floating point (for cases where the result won't
1990 overflow). Before, floating point was always used, which could lead to
28e5dec8
JH
1991 loss of precision compared with integer addition.
1992
1993 * making IV and NV equal status should make maths accurate on 64 bit
1994 platforms
1995 * may speed up maths somewhat if pp_add and friends start to use
645c22ef 1996 integers when possible instead of fp. (Hopefully the overhead in
28e5dec8
JH
1997 looking for SvIOK and checking for overflow will not outweigh the
1998 fp to integer speedup)
1999 * will slow down integer operations (callers of SvIV) on "inaccurate"
2000 values, as the change from SvIOK to SvIOKp will cause a call into
2001 sv_2iv each time rather than a macro access direct to the IV slot
2002 * should speed up number->string conversion on integers as IV is
645c22ef 2003 favoured when IV and NV are equally accurate
28e5dec8
JH
2004
2005 ####################################################################
645c22ef
DM
2006 You had better be using SvIOK_notUV if you want an IV for arithmetic:
2007 SvIOK is true if (IV or UV), so you might be getting (IV)SvUV.
2008 On the other hand, SvUOK is true iff UV.
28e5dec8
JH
2009 ####################################################################
2010
645c22ef 2011 Your mileage will vary depending your CPU's relative fp to integer
28e5dec8
JH
2012 performance ratio.
2013*/
2014
2015#ifndef NV_PRESERVES_UV
645c22ef
DM
2016# define IS_NUMBER_UNDERFLOW_IV 1
2017# define IS_NUMBER_UNDERFLOW_UV 2
2018# define IS_NUMBER_IV_AND_UV 2
2019# define IS_NUMBER_OVERFLOW_IV 4
2020# define IS_NUMBER_OVERFLOW_UV 5
2021
2022/* sv_2iuv_non_preserve(): private routine for use by sv_2iv() and sv_2uv() */
28e5dec8
JH
2023
2024/* For sv_2nv these three cases are "SvNOK and don't bother casting" */
2025STATIC int
5aaab254 2026S_sv_2iuv_non_preserve(pTHX_ SV *const sv
47031da6
NC
2027# ifdef DEBUGGING
2028 , I32 numtype
2029# endif
2030 )
28e5dec8 2031{
7918f24d 2032 PERL_ARGS_ASSERT_SV_2IUV_NON_PRESERVE;
23491f1d 2033 PERL_UNUSED_CONTEXT;
7918f24d 2034
3f7c398e 2035 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
2036 if (SvNVX(sv) < (NV)IV_MIN) {
2037 (void)SvIOKp_on(sv);
2038 (void)SvNOK_on(sv);
45977657 2039 SvIV_set(sv, IV_MIN);
28e5dec8
JH
2040 return IS_NUMBER_UNDERFLOW_IV;
2041 }
2042 if (SvNVX(sv) > (NV)UV_MAX) {
2043 (void)SvIOKp_on(sv);
2044 (void)SvNOK_on(sv);
2045 SvIsUV_on(sv);
607fa7f2 2046 SvUV_set(sv, UV_MAX);
28e5dec8
JH
2047 return IS_NUMBER_OVERFLOW_UV;
2048 }
c2988b20
NC
2049 (void)SvIOKp_on(sv);
2050 (void)SvNOK_on(sv);
2051 /* Can't use strtol etc to convert this string. (See truth table in
2052 sv_2iv */
2053 if (SvNVX(sv) <= (UV)IV_MAX) {
45977657 2054 SvIV_set(sv, I_V(SvNVX(sv)));
659c4b96 2055 if ((NV)(SvIVX(sv)) == SvNVX(sv)) {
c2988b20
NC
2056 SvIOK_on(sv); /* Integer is precise. NOK, IOK */
2057 } else {
2058 /* Integer is imprecise. NOK, IOKp */
2059 }
2060 return SvNVX(sv) < 0 ? IS_NUMBER_UNDERFLOW_UV : IS_NUMBER_IV_AND_UV;
2061 }
2062 SvIsUV_on(sv);
607fa7f2 2063 SvUV_set(sv, U_V(SvNVX(sv)));
659c4b96 2064 if ((NV)(SvUVX(sv)) == SvNVX(sv)) {
c2988b20
NC
2065 if (SvUVX(sv) == UV_MAX) {
2066 /* As we know that NVs don't preserve UVs, UV_MAX cannot
2067 possibly be preserved by NV. Hence, it must be overflow.
2068 NOK, IOKp */
2069 return IS_NUMBER_OVERFLOW_UV;
2070 }
2071 SvIOK_on(sv); /* Integer is precise. NOK, UOK */
2072 } else {
2073 /* Integer is imprecise. NOK, IOKp */
28e5dec8 2074 }
c2988b20 2075 return IS_NUMBER_OVERFLOW_IV;
28e5dec8 2076}
645c22ef
DM
2077#endif /* !NV_PRESERVES_UV*/
2078
a13f4dff 2079/* If numtype is infnan, set the NV of the sv accordingly.
5564cd7f 2080 * If numtype is anything else, try setting the NV using Atof(PV). */
a13f4dff 2081static void
5564cd7f 2082S_sv_setnv(pTHX_ SV* sv, int numtype)
a13f4dff 2083{
07925c5e 2084 bool pok = cBOOL(SvPOK(sv));
5564cd7f 2085 bool nok = FALSE;
a13f4dff
JH
2086 if ((numtype & IS_NUMBER_INFINITY)) {
2087 SvNV_set(sv, (numtype & IS_NUMBER_NEG) ? -NV_INF : NV_INF);
5564cd7f 2088 nok = TRUE;
a13f4dff
JH
2089 }
2090 else if ((numtype & IS_NUMBER_NAN)) {
2091 SvNV_set(sv, NV_NAN);
d48bd569 2092 nok = TRUE;
a13f4dff 2093 }
d48bd569 2094 else if (pok) {
a13f4dff 2095 SvNV_set(sv, Atof(SvPVX_const(sv)));
d48bd569
JH
2096 /* Purposefully no true nok here, since we don't want to blow
2097 * away the possible IOK/UV of an existing sv. */
2098 }
5564cd7f 2099 if (nok) {
d48bd569 2100 SvNOK_only(sv); /* No IV or UV please, this is pure infnan. */
5564cd7f
JH
2101 if (pok)
2102 SvPOK_on(sv); /* PV is okay, though. */
2103 }
a13f4dff
JH
2104}
2105
af359546 2106STATIC bool
7918f24d
NC
2107S_sv_2iuv_common(pTHX_ SV *const sv)
2108{
7918f24d
NC
2109 PERL_ARGS_ASSERT_SV_2IUV_COMMON;
2110
af359546 2111 if (SvNOKp(sv)) {
28e5dec8
JH
2112 /* erm. not sure. *should* never get NOKp (without NOK) from sv_2nv
2113 * without also getting a cached IV/UV from it at the same time
2114 * (ie PV->NV conversion should detect loss of accuracy and cache
af359546
NC
2115 * IV or UV at same time to avoid this. */
2116 /* IV-over-UV optimisation - choose to cache IV if possible */
25da4f38 2117
a83034fc 2118 if (UNLIKELY(Perl_isinfnan(SvNVX(sv))))
0f83c5a4
JH
2119 return FALSE;
2120
25da4f38
IZ
2121 if (SvTYPE(sv) == SVt_NV)
2122 sv_upgrade(sv, SVt_PVNV);
2123
28e5dec8
JH
2124 (void)SvIOKp_on(sv); /* Must do this first, to clear any SvOOK */
2125 /* < not <= as for NV doesn't preserve UV, ((NV)IV_MAX+1) will almost
2126 certainly cast into the IV range at IV_MAX, whereas the correct
2127 answer is the UV IV_MAX +1. Hence < ensures that dodgy boundary
2128 cases go to UV */
2129 if (SvNVX(sv) < (NV)IV_MAX + 0.5) {
45977657 2130 SvIV_set(sv, I_V(SvNVX(sv)));
659c4b96 2131 if (SvNVX(sv) == (NV) SvIVX(sv)
28e5dec8
JH
2132#ifndef NV_PRESERVES_UV
2133 && (((UV)1 << NV_PRESERVES_UV_BITS) >
2134 (UV)(SvIVX(sv) > 0 ? SvIVX(sv) : -SvIVX(sv)))
2135 /* Don't flag it as "accurately an integer" if the number
2136 came from a (by definition imprecise) NV operation, and
2137 we're outside the range of NV integer precision */
2138#endif
2139 ) {
a43d94f2
NC
2140 if (SvNOK(sv))
2141 SvIOK_on(sv); /* Can this go wrong with rounding? NWC */
2142 else {
2143 /* scalar has trailing garbage, eg "42a" */
2144 }
28e5dec8 2145 DEBUG_c(PerlIO_printf(Perl_debug_log,
7234c960 2146 "0x%"UVxf" iv(%"NVgf" => %"IVdf") (precise)\n",
28e5dec8
JH
2147 PTR2UV(sv),
2148 SvNVX(sv),
2149 SvIVX(sv)));
2150
2151 } else {
2152 /* IV not precise. No need to convert from PV, as NV
2153 conversion would already have cached IV if it detected
2154 that PV->IV would be better than PV->NV->IV
2155 flags already correct - don't set public IOK. */
2156 DEBUG_c(PerlIO_printf(Perl_debug_log,
7234c960 2157 "0x%"UVxf" iv(%"NVgf" => %"IVdf") (imprecise)\n",
28e5dec8
JH
2158 PTR2UV(sv),
2159 SvNVX(sv),
2160 SvIVX(sv)));
2161 }
2162 /* Can the above go wrong if SvIVX == IV_MIN and SvNVX < IV_MIN,
2163 but the cast (NV)IV_MIN rounds to a the value less (more
2164 negative) than IV_MIN which happens to be equal to SvNVX ??
2165 Analogous to 0xFFFFFFFFFFFFFFFF rounding up to NV (2**64) and
2166 NV rounding back to 0xFFFFFFFFFFFFFFFF, so UVX == UV(NVX) and
2167 (NV)UVX == NVX are both true, but the values differ. :-(
2168 Hopefully for 2s complement IV_MIN is something like
2169 0x8000000000000000 which will be exact. NWC */
d460ef45 2170 }
25da4f38 2171 else {
607fa7f2 2172 SvUV_set(sv, U_V(SvNVX(sv)));
28e5dec8 2173 if (
659c4b96 2174 (SvNVX(sv) == (NV) SvUVX(sv))
28e5dec8
JH
2175#ifndef NV_PRESERVES_UV
2176 /* Make sure it's not 0xFFFFFFFFFFFFFFFF */
2177 /*&& (SvUVX(sv) != UV_MAX) irrelevant with code below */
2178 && (((UV)1 << NV_PRESERVES_UV_BITS) > SvUVX(sv))
2179 /* Don't flag it as "accurately an integer" if the number
2180 came from a (by definition imprecise) NV operation, and
2181 we're outside the range of NV integer precision */
2182#endif
a43d94f2 2183 && SvNOK(sv)
28e5dec8
JH
2184 )
2185 SvIOK_on(sv);
25da4f38 2186 SvIsUV_on(sv);
1c846c1f 2187 DEBUG_c(PerlIO_printf(Perl_debug_log,
57def98f 2188 "0x%"UVxf" 2iv(%"UVuf" => %"IVdf") (as unsigned)\n",
56431972 2189 PTR2UV(sv),
57def98f
JH
2190 SvUVX(sv),
2191 SvUVX(sv)));
25da4f38 2192 }
748a9306 2193 }
cd84013a 2194 else if (SvPOKp(sv)) {
c2988b20 2195 UV value;
504618e9 2196 const int numtype = grok_number(SvPVX_const(sv), SvCUR(sv), &value);
af359546 2197 /* We want to avoid a possible problem when we cache an IV/ a UV which
25da4f38 2198 may be later translated to an NV, and the resulting NV is not
c2988b20
NC
2199 the same as the direct translation of the initial string
2200 (eg 123.456 can shortcut to the IV 123 with atol(), but we must
2201 be careful to ensure that the value with the .456 is around if the
2202 NV value is requested in the future).
1c846c1f 2203
af359546 2204 This means that if we cache such an IV/a UV, we need to cache the
25da4f38 2205 NV as well. Moreover, we trade speed for space, and do not
28e5dec8 2206 cache the NV if we are sure it's not needed.
25da4f38 2207 */
16b7a9a4 2208
c2988b20
NC
2209 /* SVt_PVNV is one higher than SVt_PVIV, hence this order */
2210 if ((numtype & (IS_NUMBER_IN_UV | IS_NUMBER_NOT_INT))
2211 == IS_NUMBER_IN_UV) {
5e045b90 2212 /* It's definitely an integer, only upgrade to PVIV */
28e5dec8
JH
2213 if (SvTYPE(sv) < SVt_PVIV)
2214 sv_upgrade(sv, SVt_PVIV);
f7bbb42a 2215 (void)SvIOK_on(sv);
c2988b20
NC
2216 } else if (SvTYPE(sv) < SVt_PVNV)
2217 sv_upgrade(sv, SVt_PVNV);
28e5dec8 2218
a13f4dff 2219 if ((numtype & (IS_NUMBER_INFINITY | IS_NUMBER_NAN))) {
5564cd7f 2220 S_sv_setnv(aTHX_ sv, numtype);
a13f4dff
JH
2221 return FALSE;
2222 }
2223
f2524eef 2224 /* If NVs preserve UVs then we only use the UV value if we know that
c2988b20
NC
2225 we aren't going to call atof() below. If NVs don't preserve UVs
2226 then the value returned may have more precision than atof() will
2227 return, even though value isn't perfectly accurate. */
2228 if ((numtype & (IS_NUMBER_IN_UV
2229#ifdef NV_PRESERVES_UV
2230 | IS_NUMBER_NOT_INT
2231#endif
2232 )) == IS_NUMBER_IN_UV) {
2233 /* This won't turn off the public IOK flag if it was set above */
2234 (void)SvIOKp_on(sv);
2235
2236 if (!(numtype & IS_NUMBER_NEG)) {
2237 /* positive */;
2238 if (value <= (UV)IV_MAX) {
45977657 2239 SvIV_set(sv, (IV)value);
c2988b20 2240 } else {
af359546 2241 /* it didn't overflow, and it was positive. */
607fa7f2 2242 SvUV_set(sv, value);
c2988b20
NC
2243 SvIsUV_on(sv);
2244 }
2245 } else {
2246 /* 2s complement assumption */
2247 if (value <= (UV)IV_MIN) {
45977657 2248 SvIV_set(sv, -(IV)value);
c2988b20
NC
2249 } else {
2250 /* Too negative for an IV. This is a double upgrade, but
d1be9408 2251 I'm assuming it will be rare. */
c2988b20
NC
2252 if (SvTYPE(sv) < SVt_PVNV)
2253 sv_upgrade(sv, SVt_PVNV);
2254 SvNOK_on(sv);
2255 SvIOK_off(sv);
2256 SvIOKp_on(sv);
9d6ce603 2257 SvNV_set(sv, -(NV)value);
45977657 2258 SvIV_set(sv, IV_MIN);
c2988b20
NC
2259 }
2260 }
2261 }
2262 /* For !NV_PRESERVES_UV and IS_NUMBER_IN_UV and IS_NUMBER_NOT_INT we
2263 will be in the previous block to set the IV slot, and the next
2264 block to set the NV slot. So no else here. */
2265
2266 if ((numtype & (IS_NUMBER_IN_UV | IS_NUMBER_NOT_INT))
2267 != IS_NUMBER_IN_UV) {
2268 /* It wasn't an (integer that doesn't overflow the UV). */
5564cd7f 2269 S_sv_setnv(aTHX_ sv, numtype);
28e5dec8 2270
c2988b20
NC
2271 if (! numtype && ckWARN(WARN_NUMERIC))
2272 not_a_number(sv);
28e5dec8 2273
88cb8500 2274 DEBUG_c(PerlIO_printf(Perl_debug_log, "0x%"UVxf" 2iv(%" NVgf ")\n",
c2988b20 2275 PTR2UV(sv), SvNVX(sv)));
28e5dec8 2276
28e5dec8 2277#ifdef NV_PRESERVES_UV
af359546
NC
2278 (void)SvIOKp_on(sv);
2279 (void)SvNOK_on(sv);
2280 if (SvNVX(sv) < (NV)IV_MAX + 0.5) {
2281 SvIV_set(sv, I_V(SvNVX(sv)));
2282 if ((NV)(SvIVX(sv)) == SvNVX(sv)) {
2283 SvIOK_on(sv);
2284 } else {
6f207bd3 2285 NOOP; /* Integer is imprecise. NOK, IOKp */
af359546
NC
2286 }
2287 /* UV will not work better than IV */
2288 } else {
2289 if (SvNVX(sv) > (NV)UV_MAX) {
2290 SvIsUV_on(sv);
2291 /* Integer is inaccurate. NOK, IOKp, is UV */
2292 SvUV_set(sv, UV_MAX);
af359546
NC
2293 } else {
2294 SvUV_set(sv, U_V(SvNVX(sv)));
2295 /* 0xFFFFFFFFFFFFFFFF not an issue in here, NVs
2296 NV preservse UV so can do correct comparison. */
2297 if ((NV)(SvUVX(sv)) == SvNVX(sv)) {
2298 SvIOK_on(sv);
af359546 2299 } else {
6f207bd3 2300 NOOP; /* Integer is imprecise. NOK, IOKp, is UV */
af359546
NC
2301 }
2302 }
4b0c9573 2303 SvIsUV_on(sv);
af359546 2304 }
28e5dec8 2305#else /* NV_PRESERVES_UV */
c2988b20
NC
2306 if ((numtype & (IS_NUMBER_IN_UV | IS_NUMBER_NOT_INT))
2307 == (IS_NUMBER_IN_UV | IS_NUMBER_NOT_INT)) {
af359546 2308 /* The IV/UV slot will have been set from value returned by
c2988b20
NC
2309 grok_number above. The NV slot has just been set using
2310 Atof. */
560b0c46 2311 SvNOK_on(sv);
c2988b20
NC
2312 assert (SvIOKp(sv));
2313 } else {
2314 if (((UV)1 << NV_PRESERVES_UV_BITS) >
2315 U_V(SvNVX(sv) > 0 ? SvNVX(sv) : -SvNVX(sv))) {
2316 /* Small enough to preserve all bits. */
2317 (void)SvIOKp_on(sv);
2318 SvNOK_on(sv);
45977657 2319 SvIV_set(sv, I_V(SvNVX(sv)));
659c4b96 2320 if ((NV)(SvIVX(sv)) == SvNVX(sv))
c2988b20
NC
2321 SvIOK_on(sv);
2322 /* Assumption: first non-preserved integer is < IV_MAX,
2323 this NV is in the preserved range, therefore: */
2324 if (!(U_V(SvNVX(sv) > 0 ? SvNVX(sv) : -SvNVX(sv))
2325 < (UV)IV_MAX)) {
32fdb065 2326 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
2327 }
2328 } else {
2329 /* IN_UV NOT_INT
2330 0 0 already failed to read UV.
2331 0 1 already failed to read UV.
2332 1 0 you won't get here in this case. IV/UV
2333 slot set, public IOK, Atof() unneeded.
2334 1 1 already read UV.
2335 so there's no point in sv_2iuv_non_preserve() attempting
2336 to use atol, strtol, strtoul etc. */
47031da6 2337# ifdef DEBUGGING
40a17c4c 2338 sv_2iuv_non_preserve (sv, numtype);
47031da6
NC
2339# else
2340 sv_2iuv_non_preserve (sv);
2341# endif
c2988b20
NC
2342 }
2343 }
28e5dec8 2344#endif /* NV_PRESERVES_UV */
a43d94f2
NC
2345 /* It might be more code efficient to go through the entire logic above
2346 and conditionally set with SvIOKp_on() rather than SvIOK(), but it
2347 gets complex and potentially buggy, so more programmer efficient
2348 to do it this way, by turning off the public flags: */
2349 if (!numtype)
2350 SvFLAGS(sv) &= ~(SVf_IOK|SVf_NOK);
25da4f38 2351 }
af359546
NC
2352 }
2353 else {
675c862f 2354 if (isGV_with_GP(sv))
159b6efe 2355 return glob_2number(MUTABLE_GV(sv));
180488f8 2356
4f62cd62 2357 if (!PL_localizing && ckWARN(WARN_UNINITIALIZED))
af359546 2358 report_uninit(sv);
25da4f38
IZ
2359 if (SvTYPE(sv) < SVt_IV)
2360 /* Typically the caller expects that sv_any is not NULL now. */
2361 sv_upgrade(sv, SVt_IV);
af359546
NC
2362 /* Return 0 from the caller. */
2363 return TRUE;
2364 }
2365 return FALSE;
2366}
2367
2368/*
2369=for apidoc sv_2iv_flags
2370
2371Return the integer value of an SV, doing any necessary string
2372conversion. If flags includes SV_GMAGIC, does an mg_get() first.
2373Normally used via the C<SvIV(sv)> and C<SvIVx(sv)> macros.
2374
2375=cut
2376*/
2377
2378IV
5aaab254 2379Perl_sv_2iv_flags(pTHX_ SV *const sv, const I32 flags)
af359546 2380{
1061065f 2381 PERL_ARGS_ASSERT_SV_2IV_FLAGS;
4bac9ae4 2382
217f6fa3
FC
2383 assert (SvTYPE(sv) != SVt_PVAV && SvTYPE(sv) != SVt_PVHV
2384 && SvTYPE(sv) != SVt_PVFM);
2385
4bac9ae4
CS
2386 if (SvGMAGICAL(sv) && (flags & SV_GMAGIC))
2387 mg_get(sv);
2388
a83034fc 2389 if (SvNOK(sv) && UNLIKELY(Perl_isinfnan(SvNVX(sv))))
0f83c5a4
JH
2390 return 0; /* So wrong but what can we do. */
2391
4bac9ae4
CS
2392 if (SvROK(sv)) {
2393 if (SvAMAGIC(sv)) {
2394 SV * tmpstr;
2395 if (flags & SV_SKIP_OVERLOAD)
2396 return 0;
2397 tmpstr = AMG_CALLunary(sv, numer_amg);
2398 if (tmpstr && (!SvROK(tmpstr) || (SvRV(tmpstr) != SvRV(sv)))) {
2399 return SvIV(tmpstr);
2400 }
2401 }
2402 return PTR2IV(SvRV(sv));
2403 }
2404
8d919b0a 2405 if (SvVALID(sv) || isREGEXP(sv)) {
2b2b6d6d
NC
2406 /* FBMs use the space for SvIVX and SvNVX for other purposes, and use
2407 the same flag bit as SVf_IVisUV, so must not let them cache IVs.
2408 In practice they are extremely unlikely to actually get anywhere
2409 accessible by user Perl code - the only way that I'm aware of is when
2410 a constant subroutine which is used as the second argument to index.
cd84013a
FC
2411
2412 Regexps have no SvIVX and SvNVX fields.
2b2b6d6d 2413 */
8d919b0a 2414 assert(isREGEXP(sv) || SvPOKp(sv));
e20b6c3b 2415 {
71c558c3 2416 UV value;
8d919b0a
FC
2417 const char * const ptr =
2418 isREGEXP(sv) ? RX_WRAPPED((REGEXP*)sv) : SvPVX_const(sv);
0f83c5a4
JH
2419 const int numtype = grok_number(ptr, SvCUR(sv), &value);
2420
2421 assert((numtype & (IS_NUMBER_INFINITY | IS_NUMBER_NAN)) == 0);
71c558c3
NC
2422
2423 if ((numtype & (IS_NUMBER_IN_UV | IS_NUMBER_NOT_INT))
2424 == IS_NUMBER_IN_UV) {
2425 /* It's definitely an integer */
2426 if (numtype & IS_NUMBER_NEG) {
2427 if (value < (UV)IV_MIN)
2428 return -(IV)value;
2429 } else {
2430 if (value < (UV)IV_MAX)
2431 return (IV)value;
2432 }
2433 }
058b8ae2 2434
71c558c3
NC
2435 if (!numtype) {
2436 if (ckWARN(WARN_NUMERIC))
2437 not_a_number(sv);
2438 }
8d919b0a 2439 return I_V(Atof(ptr));
e20b6c3b 2440 }
4bac9ae4
CS
2441 }
2442
2443 if (SvTHINKFIRST(sv)) {
73381561 2444#ifdef PERL_OLD_COPY_ON_WRITE
af359546
NC
2445 if (SvIsCOW(sv)) {
2446 sv_force_normal_flags(sv, 0);
2447 }
73381561 2448#endif
af359546
NC
2449 if (SvREADONLY(sv) && !SvOK(sv)) {
2450 if (ckWARN(WARN_UNINITIALIZED))
2451 report_uninit(sv);
2452 return 0;
2453 }
2454 }
4bac9ae4 2455
af359546
NC
2456 if (!SvIOKp(sv)) {
2457 if (S_sv_2iuv_common(aTHX_ sv))
2458 return 0;
79072805 2459 }
4bac9ae4 2460
1d7c1841
GS
2461 DEBUG_c(PerlIO_printf(Perl_debug_log, "0x%"UVxf" 2iv(%"IVdf")\n",
2462 PTR2UV(sv),SvIVX(sv)));
25da4f38 2463 return SvIsUV(sv) ? (IV)SvUVX(sv) : SvIVX(sv);
79072805
LW
2464}
2465
645c22ef 2466/*
891f9566 2467=for apidoc sv_2uv_flags
645c22ef
DM
2468
2469Return the unsigned integer value of an SV, doing any necessary string
891f9566
YST
2470conversion. If flags includes SV_GMAGIC, does an mg_get() first.
2471Normally used via the C<SvUV(sv)> and C<SvUVx(sv)> macros.
645c22ef
DM
2472
2473=cut
2474*/
2475
ff68c719 2476UV
5aaab254 2477Perl_sv_2uv_flags(pTHX_ SV *const sv, const I32 flags)
ff68c719 2478{
1061065f 2479 PERL_ARGS_ASSERT_SV_2UV_FLAGS;
4bac9ae4
CS
2480
2481 if (SvGMAGICAL(sv) && (flags & SV_GMAGIC))
2482 mg_get(sv);
2483
a83034fc 2484 if (SvNOK(sv) && UNLIKELY(Perl_isinfnan(SvNVX(sv))))
0f83c5a4
JH
2485 return 0; /* So wrong but what can we do. */
2486
4bac9ae4
CS
2487 if (SvROK(sv)) {
2488 if (SvAMAGIC(sv)) {
2489 SV *tmpstr;
2490 if (flags & SV_SKIP_OVERLOAD)
2491 return 0;
2492 tmpstr = AMG_CALLunary(sv, numer_amg);
2493 if (tmpstr && (!SvROK(tmpstr) || (SvRV(tmpstr) != SvRV(sv)))) {
2494 return SvUV(tmpstr);
2495 }
2496 }
2497 return PTR2UV(SvRV(sv));
2498 }
2499
8d919b0a 2500 if (SvVALID(sv) || isREGEXP(sv)) {
2b2b6d6d 2501 /* FBMs use the space for SvIVX and SvNVX for other purposes, and use
cd84013a
FC
2502 the same flag bit as SVf_IVisUV, so must not let them cache IVs.
2503 Regexps have no SvIVX and SvNVX fields. */
8d919b0a 2504 assert(isREGEXP(sv) || SvPOKp(sv));
e20b6c3b 2505 {
71c558c3 2506 UV value;
8d919b0a
FC
2507 const char * const ptr =
2508 isREGEXP(sv) ? RX_WRAPPED((REGEXP*)sv) : SvPVX_const(sv);
0f83c5a4
JH
2509 const int numtype = grok_number(ptr, SvCUR(sv), &value);
2510
2511 assert((numtype & (IS_NUMBER_INFINITY | IS_NUMBER_NAN)) == 0);
71c558c3
NC
2512
2513 if ((numtype & (IS_NUMBER_IN_UV | IS_NUMBER_NOT_INT))
2514 == IS_NUMBER_IN_UV) {
2515 /* It's definitely an integer */
2516 if (!(numtype & IS_NUMBER_NEG))
2517 return value;
2518 }
058b8ae2 2519
71c558c3
NC
2520 if (!numtype) {
2521 if (ckWARN(WARN_NUMERIC))
2522 not_a_number(sv);
2523 }
8d919b0a 2524 return U_V(Atof(ptr));
e20b6c3b 2525 }
4bac9ae4
CS
2526 }
2527
2528 if (SvTHINKFIRST(sv)) {
73381561 2529#ifdef PERL_OLD_COPY_ON_WRITE
765f542d
NC
2530 if (SvIsCOW(sv)) {
2531 sv_force_normal_flags(sv, 0);
8a818333 2532 }
73381561 2533#endif
0336b60e 2534 if (SvREADONLY(sv) && !SvOK(sv)) {
0336b60e 2535 if (ckWARN(WARN_UNINITIALIZED))
29489e7c 2536 report_uninit(sv);
ff68c719
PP
2537 return 0;
2538 }
2539 }
4bac9ae4 2540
af359546
NC
2541 if (!SvIOKp(sv)) {
2542 if (S_sv_2iuv_common(aTHX_ sv))
2543 return 0;
ff68c719 2544 }
25da4f38 2545
1d7c1841
GS
2546 DEBUG_c(PerlIO_printf(Perl_debug_log, "0x%"UVxf" 2uv(%"UVuf")\n",
2547 PTR2UV(sv),SvUVX(sv)));
25da4f38 2548 return SvIsUV(sv) ? SvUVX(sv) : (UV)SvIVX(sv);
ff68c719
PP
2549}
2550
645c22ef 2551/*
196007d1 2552=for apidoc sv_2nv_flags
645c22ef
DM
2553
2554Return the num value of an SV, doing any necessary string or integer
fde67290 2555conversion. If flags includes SV_GMAGIC, does an mg_get() first.
39d5de13 2556Normally used via the C<SvNV(sv)> and C<SvNVx(sv)> macros.
645c22ef
DM
2557
2558=cut
2559*/
2560
65202027 2561NV
5aaab254 2562Perl_sv_2nv_flags(pTHX_ SV *const sv, const I32 flags)
79072805 2563{
1061065f
DD
2564 PERL_ARGS_ASSERT_SV_2NV_FLAGS;
2565
217f6fa3
FC
2566 assert (SvTYPE(sv) != SVt_PVAV && SvTYPE(sv) != SVt_PVHV
2567 && SvTYPE(sv) != SVt_PVFM);
8d919b0a 2568 if (SvGMAGICAL(sv) || SvVALID(sv) || isREGEXP(sv)) {
2b2b6d6d 2569 /* FBMs use the space for SvIVX and SvNVX for other purposes, and use
cd84013a
FC
2570 the same flag bit as SVf_IVisUV, so must not let them cache NVs.
2571 Regexps have no SvIVX and SvNVX fields. */
8d919b0a 2572 const char *ptr;
39d5de13
DM
2573 if (flags & SV_GMAGIC)
2574 mg_get(sv);
463ee0b2
LW
2575 if (SvNOKp(sv))
2576 return SvNVX(sv);
cd84013a 2577 if (SvPOKp(sv) && !SvIOKp(sv)) {
8d919b0a
FC
2578 ptr = SvPVX_const(sv);
2579 grokpv:
041457d9 2580 if (!SvIOKp(sv) && ckWARN(WARN_NUMERIC) &&
8d919b0a 2581 !grok_number(ptr, SvCUR(sv), NULL))
a0d0e21e 2582 not_a_number(sv);
8d919b0a 2583 return Atof(ptr);
a0d0e21e 2584 }
25da4f38 2585 if (SvIOKp(sv)) {
1c846c1f 2586 if (SvIsUV(sv))
65202027 2587 return (NV)SvUVX(sv);
25da4f38 2588 else
65202027 2589 return (NV)SvIVX(sv);
47a72cb8
NC
2590 }
2591 if (SvROK(sv)) {
2592 goto return_rok;
2593 }
8d919b0a
FC
2594 if (isREGEXP(sv)) {
2595 ptr = RX_WRAPPED((REGEXP *)sv);
2596 goto grokpv;
2597 }
47a72cb8
NC
2598 assert(SvTYPE(sv) >= SVt_PVMG);
2599 /* This falls through to the report_uninit near the end of the
2600 function. */
2601 } else if (SvTHINKFIRST(sv)) {
a0d0e21e 2602 if (SvROK(sv)) {
47a72cb8 2603 return_rok:
deb46114 2604 if (SvAMAGIC(sv)) {
aee036bb
DM
2605 SV *tmpstr;
2606 if (flags & SV_SKIP_OVERLOAD)
2607 return 0;
31d632c3 2608 tmpstr = AMG_CALLunary(sv, numer_amg);
deb46114
NC
2609 if (tmpstr && (!SvROK(tmpstr) || (SvRV(tmpstr) != SvRV(sv)))) {
2610 return SvNV(tmpstr);
2611 }
2612 }
2613 return PTR2NV(SvRV(sv));
a0d0e21e 2614 }
73381561 2615#ifdef PERL_OLD_COPY_ON_WRITE
765f542d
NC
2616 if (SvIsCOW(sv)) {
2617 sv_force_normal_flags(sv, 0);
8a818333 2618 }
73381561 2619#endif
0336b60e 2620 if (SvREADONLY(sv) && !SvOK(sv)) {
599cee73 2621 if (ckWARN(WARN_UNINITIALIZED))
29489e7c 2622 report_uninit(sv);
ed6116ce
LW
2623 return 0.0;
2624 }
79072805
LW
2625 }
2626 if (SvTYPE(sv) < SVt_NV) {
7e25a7e9
NC
2627 /* The logic to use SVt_PVNV if necessary is in sv_upgrade. */
2628 sv_upgrade(sv, SVt_NV);
097ee67d 2629 DEBUG_c({
f93f4e46 2630 STORE_NUMERIC_LOCAL_SET_STANDARD();
1d7c1841 2631 PerlIO_printf(Perl_debug_log,
88cb8500 2632 "0x%"UVxf" num(%" NVgf ")\n",
1d7c1841 2633 PTR2UV(sv), SvNVX(sv));
097ee67d
JH
2634 RESTORE_NUMERIC_LOCAL();
2635 });
79072805
LW
2636 }
2637 else if (SvTYPE(sv) < SVt_PVNV)
2638 sv_upgrade(sv, SVt_PVNV);
59d8ce62
NC
2639 if (SvNOKp(sv)) {
2640 return SvNVX(sv);
61604483 2641 }
59d8ce62 2642 if (SvIOKp(sv)) {
9d6ce603 2643 SvNV_set(sv, SvIsUV(sv) ? (NV)SvUVX(sv) : (NV)SvIVX(sv));
28e5dec8 2644#ifdef NV_PRESERVES_UV
a43d94f2
NC
2645 if (SvIOK(sv))
2646 SvNOK_on(sv);
2647 else
2648 SvNOKp_on(sv);
28e5dec8
JH
2649#else
2650 /* Only set the public NV OK flag if this NV preserves the IV */
2651 /* Check it's not 0xFFFFFFFFFFFFFFFF */
a43d94f2
NC
2652 if (SvIOK(sv) &&
2653 SvIsUV(sv) ? ((SvUVX(sv) != UV_MAX)&&(SvUVX(sv) == U_V(SvNVX(sv))))
28e5dec8
JH
2654 : (SvIVX(sv) == I_V(SvNVX(sv))))
2655 SvNOK_on(sv);
2656 else
2657 SvNOKp_on(sv);
2658#endif
93a17b20 2659 }
cd84013a 2660 else if (SvPOKp(sv)) {
c2988b20 2661 UV value;
3f7c398e 2662 const int numtype = grok_number(SvPVX_const(sv), SvCUR(sv), &value);
041457d9 2663 if (!SvIOKp(sv) && !numtype && ckWARN(WARN_NUMERIC))
a0d0e21e 2664 not_a_number(sv);
28e5dec8 2665#ifdef NV_PRESERVES_UV
c2988b20
NC
2666 if ((numtype & (IS_NUMBER_IN_UV | IS_NUMBER_NOT_INT))
2667 == IS_NUMBER_IN_UV) {
5e045b90 2668 /* It's definitely an integer */
9d6ce603 2669 SvNV_set(sv, (numtype & IS_NUMBER_NEG) ? -(NV)value : (NV)value);
66d83377 2670 } else {
5564cd7f 2671 S_sv_setnv(aTHX_ sv, numtype);
66d83377 2672 }
a43d94f2
NC
2673 if (numtype)
2674 SvNOK_on(sv);
2675 else
2676 SvNOKp_on(sv);
28e5dec8 2677#else
0f83c5a4
JH
2678 if ((numtype & IS_NUMBER_INFINITY)) {
2679 SvNV_set(sv, (numtype & IS_NUMBER_NEG) ? -NV_INF : NV_INF);
2680 SvNOK_on(sv);
2681 } else if ((numtype & IS_NUMBER_NAN)) {
2682 SvNV_set(sv, NV_NAN);
c2988b20
NC
2683 SvNOK_on(sv);
2684 } else {
0f83c5a4
JH
2685 SvNV_set(sv, Atof(SvPVX_const(sv)));
2686 /* Only set the public NV OK flag if this NV preserves the value in
2687 the PV at least as well as an IV/UV would.
2688 Not sure how to do this 100% reliably. */
2689 /* if that shift count is out of range then Configure's test is
2690 wonky. We shouldn't be in here with NV_PRESERVES_UV_BITS ==
2691 UV_BITS */
2692 if (((UV)1 << NV_PRESERVES_UV_BITS) >
2693 U_V(SvNVX(sv) > 0 ? SvNVX(sv) : -SvNVX(sv))) {
2694 SvNOK_on(sv); /* Definitely small enough to preserve all bits */
2695 } else if (!(numtype & IS_NUMBER_IN_UV)) {
2696 /* Can't use strtol etc to convert this string, so don't try.
2697 sv_2iv and sv_2uv will use the NV to convert, not the PV. */
2698 SvNOK_on(sv);
c2988b20 2699 } else {
0f83c5a4
JH
2700 /* value has been set. It may not be precise. */
2701 if ((numtype & IS_NUMBER_NEG) && (value > (UV)IV_MIN)) {
2702 /* 2s complement assumption for (UV)IV_MIN */
2703 SvNOK_on(sv); /* Integer is too negative. */
c2988b20 2704 } else {
0f83c5a4
JH
2705 SvNOKp_on(sv);
2706 SvIOKp_on(sv);
6fa402ec 2707
0f83c5a4
JH
2708 if (numtype & IS_NUMBER_NEG) {
2709 SvIV_set(sv, -(IV)value);
2710 } else if (value <= (UV)IV_MAX) {
2711 SvIV_set(sv, (IV)value);
2712 } else {
2713 SvUV_set(sv, value);
2714 SvIsUV_on(sv);
2715 }
c2988b20 2716
0f83c5a4
JH
2717 if (numtype & IS_NUMBER_NOT_INT) {
2718 /* I believe that even if the original PV had decimals,
2719 they are lost beyond the limit of the FP precision.
2720 However, neither is canonical, so both only get p
2721 flags. NWC, 2000/11/25 */
2722 /* Both already have p flags, so do nothing */
2723 } else {
2724 const NV nv = SvNVX(sv);
2725 if (SvNVX(sv) < (NV)IV_MAX + 0.5) {
2726 if (SvIVX(sv) == I_V(nv)) {
c2988b20 2727 SvNOK_on(sv);
0f83c5a4
JH
2728 } else {
2729 /* It had no "." so it must be integer. */
2730 }
2731 SvIOK_on(sv);
2732 } else {
2733 /* between IV_MAX and NV(UV_MAX).
2734 Could be slightly > UV_MAX */
2735
2736 if (numtype & IS_NUMBER_NOT_INT) {
2737 /* UV and NV both imprecise. */
2738 } else {
2739 const UV nv_as_uv = U_V(nv);
2740
2741 if (value == nv_as_uv && SvUVX(sv) != UV_MAX) {
2742 SvNOK_on(sv);
2743 }
2744 SvIOK_on(sv);
c2988b20
NC
2745 }
2746 }
2747 }
2748 }
2749 }
0f83c5a4
JH
2750 /* It might be more code efficient to go through the entire logic above
2751 and conditionally set with SvNOKp_on() rather than SvNOK(), but it
2752 gets complex and potentially buggy, so more programmer efficient
a43d94f2 2753 to do it this way, by turning off the public flags: */
0f83c5a4
JH
2754 if (!numtype)
2755 SvFLAGS(sv) &= ~(SVf_IOK|SVf_NOK);
2756 }
28e5dec8 2757#endif /* NV_PRESERVES_UV */
93a17b20 2758 }
79072805 2759 else {
0f83c5a4
JH
2760 if (isGV_with_GP(sv)) {
2761 glob_2number(MUTABLE_GV(sv));
2762 return 0.0;
2763 }
180488f8 2764
0f83c5a4
JH
2765 if (!PL_localizing && ckWARN(WARN_UNINITIALIZED))
2766 report_uninit(sv);
2767 assert (SvTYPE(sv) >= SVt_NV);
2768 /* Typically the caller expects that sv_any is not NULL now. */
2769 /* XXX Ilya implies that this is a bug in callers that assume this
2770 and ideally should be fixed. */
2771 return 0.0;
79072805 2772 }
097ee67d 2773 DEBUG_c({
0f83c5a4
JH
2774 STORE_NUMERIC_LOCAL_SET_STANDARD();
2775 PerlIO_printf(Perl_debug_log, "0x%"UVxf" 2nv(%" NVgf ")\n",
2776 PTR2UV(sv), SvNVX(sv));
2777 RESTORE_NUMERIC_LOCAL();
2778 });
463ee0b2 2779 return SvNVX(sv);
79072805
LW
2780}
2781
800401ee
JH
2782/*
2783=for apidoc sv_2num
2784
2785Return an SV with the numeric value of the source SV, doing any necessary
a196a5fa
JH
2786reference or overload conversion. You must use the C<SvNUM(sv)> macro to
2787access this function.
800401ee
JH
2788
2789=cut
2790*/
2791
2792SV *
5aaab254 2793Perl_sv_2num(pTHX_ SV *const sv)
800401ee 2794{
7918f24d
NC
2795 PERL_ARGS_ASSERT_SV_2NUM;
2796
b9ee0594
RGS
2797 if (!SvROK(sv))
2798 return sv;
800401ee 2799 if (SvAMAGIC(sv)) {
31d632c3 2800 SV * const tmpsv = AMG_CALLunary(sv, numer_amg);
a02ec77a 2801 TAINT_IF(tmpsv && SvTAINTED(tmpsv));
800401ee
JH
2802 if (tmpsv && (!SvROK(tmpsv) || (SvRV(tmpsv) != SvRV(sv))))
2803 return sv_2num(tmpsv);
2804 }
2805 return sv_2mortal(newSVuv(PTR2UV(SvRV(sv))));
2806}
2807
645c22ef
DM
2808/* uiv_2buf(): private routine for use by sv_2pv_flags(): print an IV or
2809 * UV as a string towards the end of buf, and return pointers to start and
2810 * end of it.
2811 *
2812 * We assume that buf is at least TYPE_CHARS(UV) long.
2813 */
2814
864dbfa3 2815static char *
5de3775c 2816S_uiv_2buf(char *const buf, const IV iv, UV uv, const int is_uv, char **const peob)
25da4f38 2817{
25da4f38 2818 char *ptr = buf + TYPE_CHARS(UV);
823a54a3 2819 char * const ebuf = ptr;
25da4f38 2820 int sign;
25da4f38 2821
7918f24d
NC
2822 PERL_ARGS_ASSERT_UIV_2BUF;
2823
25da4f38
IZ
2824 if (is_uv)
2825 sign = 0;
2826 else if (iv >= 0) {
2827 uv = iv;
2828 sign = 0;
2829 } else {
2830 uv = -iv;
2831 sign = 1;
2832 }
2833 do {
eb160463 2834 *--ptr = '0' + (char)(uv % 10);
25da4f38
IZ
2835 } while (uv /= 10);
2836 if (sign)
2837 *--ptr = '-';
2838 *peob = ebuf;
2839 return ptr;
2840}
2841
0c7e610f 2842/* Helper for sv_2pv_flags and sv_vcatpvfn_flags. If the NV is an
fde71869
JH
2843 * infinity or a not-a-number, writes the appropriate strings to the
2844 * buffer, including a zero byte. On success returns the written length,
5e85836e 2845 * excluding the zero byte, on failure (not an infinity, not a nan, or the
fb8cdbc5
JH
2846 * maxlen too small) returns zero.
2847 *
2848 * XXX for "Inf", "-Inf", and "NaN", we could have three read-only
2849 * shared string constants we point to, instead of generating a new
2850 * string for each instance. */
0c7e610f 2851STATIC size_t
5e85836e 2852S_infnan_2pv(NV nv, char* buffer, size_t maxlen) {
fb8cdbc5 2853 assert(maxlen >= 4);
5e85836e 2854 if (maxlen < 4) /* "Inf\0", "NaN\0" */
0c7e610f
JH
2855 return 0;
2856 else {
2857 char* s = buffer;
3fd158ea 2858 if (Perl_isinf(nv)) {
128eeacb
DD
2859 if (nv < 0) {
2860 if (maxlen < 5) /* "-Inf\0" */
2861 return 0;
2862 *s++ = '-';
2863 }
2864 *s++ = 'I';
2865 *s++ = 'n';
2866 *s++ = 'f';
3fd158ea
JH
2867 } else if (Perl_isnan(nv)) {
2868 *s++ = 'N';
2869 *s++ = 'a';
2870 *s++ = 'N';
2871 /* XXX optionally output the payload mantissa bits as
2872 * "(unsigned)" (to match the nan("...") C99 function,
2873 * or maybe as "(0xhhh...)" would make more sense...
2874 * provide a format string so that the user can decide?
2875 * NOTE: would affect the maxlen and assert() logic.*/
128eeacb
DD
2876 }
2877
0c7e610f
JH
2878 else
2879 return 0;
5e85836e 2880 assert((s == buffer + 3) || (s == buffer + 4));
0c7e610f 2881 *s++ = 0;
5e85836e 2882 return s - buffer - 1; /* -1: excluding the zero byte */
0c7e610f
JH
2883 }
2884}
2885
645c22ef
DM
2886/*
2887=for apidoc sv_2pv_flags
2888
ff276b08 2889Returns a pointer to the string value of an SV, and sets *lp to its length.
fde67290
FC
2890If flags includes SV_GMAGIC, does an mg_get() first. Coerces sv to a
2891string if necessary. Normally invoked via the C<SvPV_flags> macro.
2892C<sv_2pv()> and C<sv_2pv_nomg> usually end up here too.
645c22ef
DM
2893
2894=cut
2895*/
2896
8d6d96c1 2897char *
5aaab254 2898Perl_sv_2pv_flags(pTHX_ SV *const sv, STRLEN *const lp, const I32 flags)
8d6d96c1 2899{
eb578fdb 2900 char *s;
79072805 2901
1061065f
DD
2902 PERL_ARGS_ASSERT_SV_2PV_FLAGS;
2903
217f6fa3
FC
2904 assert (SvTYPE(sv) != SVt_PVAV && SvTYPE(sv) != SVt_PVHV
2905 && SvTYPE(sv) != SVt_PVFM);
4bac9ae4
CS
2906 if (SvGMAGICAL(sv) && (flags & SV_GMAGIC))
2907 mg_get(sv);
2908 if (SvROK(sv)) {
2909 if (SvAMAGIC(sv)) {
2910 SV *tmpstr;
2911 if (flags & SV_SKIP_OVERLOAD)
2912 return NULL;
2913 tmpstr = AMG_CALLunary(sv, string_amg);
2914 TAINT_IF(tmpstr && SvTAINTED(tmpstr));
2915 if (tmpstr && (!SvROK(tmpstr) || (SvRV(tmpstr) != SvRV(sv)))) {
2916 /* Unwrap this: */
2917 /* char *pv = lp ? SvPV(tmpstr, *lp) : SvPV_nolen(tmpstr);
2918 */
75dfc8ec 2919
4bac9ae4
CS
2920 char *pv;
2921 if ((SvFLAGS(tmpstr) & (SVf_POK)) == SVf_POK) {
2922 if (flags & SV_CONST_RETURN) {
2923 pv = (char *) SvPVX_const(tmpstr);
50adf7d2 2924 } else {
4bac9ae4
CS
2925 pv = (flags & SV_MUTABLE_RETURN)
2926 ? SvPVX_mutable(tmpstr) : SvPVX(tmpstr);
50adf7d2 2927 }
4bac9ae4
CS
2928 if (lp)
2929 *lp = SvCUR(tmpstr);
2930 } else {
2931 pv = sv_2pv_flags(tmpstr, lp, flags);
50adf7d2 2932 }
4bac9ae4
CS
2933 if (SvUTF8(tmpstr))
2934 SvUTF8_on(sv);
2935 else
2936 SvUTF8_off(sv);
2937 return pv;
deb46114 2938 }
4bac9ae4
CS
2939 }
2940 {
2941 STRLEN len;
2942 char *retval;
2943 char *buffer;
2944 SV *const referent = SvRV(sv);
2945
2946 if (!referent) {
2947 len = 7;
2948 retval = buffer = savepvn("NULLREF", len);
2949 } else if (SvTYPE(referent) == SVt_REGEXP &&
2950 (!(PL_curcop->cop_hints & HINT_NO_AMAGIC) ||
2951 amagic_is_enabled(string_amg))) {
2952 REGEXP * const re = (REGEXP *)MUTABLE_PTR(referent);
2953
2954 assert(re);
67d2d14d 2955
4bac9ae4
CS
2956 /* If the regex is UTF-8 we want the containing scalar to
2957 have an UTF-8 flag too */
2958 if (RX_UTF8(re))
2959 SvUTF8_on(sv);
2960 else
2961 SvUTF8_off(sv);
67d2d14d 2962
4bac9ae4
CS
2963 if (lp)
2964 *lp = RX_WRAPLEN(re);
67d2d14d 2965
4bac9ae4
CS
2966 return RX_WRAPPED(re);
2967 } else {
2968 const char *const typestr = sv_reftype(referent, 0);
2969 const STRLEN typelen = strlen(typestr);
2970 UV addr = PTR2UV(referent);
2971 const char *stashname = NULL;
2972 STRLEN stashnamelen = 0; /* hush, gcc */
2973 const char *buffer_end;
2974
2975 if (SvOBJECT(referent)) {
2976 const HEK *const name = HvNAME_HEK(SvSTASH(referent));
2977
2978 if (name) {
2979 stashname = HEK_KEY(name);
2980 stashnamelen = HEK_LEN(name);
2981
2982 if (HEK_UTF8(name)) {
2983 SvUTF8_on(sv);
fafee734 2984 } else {
4bac9ae4 2985 SvUTF8_off(sv);
fafee734 2986 }
fafee734 2987 } else {
4bac9ae4
CS
2988 stashname = "__ANON__";
2989 stashnamelen = 8;
fafee734 2990 }
4bac9ae4
CS
2991 len = stashnamelen + 1 /* = */ + typelen + 3 /* (0x */
2992 + 2 * sizeof(UV) + 2 /* )\0 */;
2993 } else {
2994 len = typelen + 3 /* (0x */
2995 + 2 * sizeof(UV) + 2 /* )\0 */;
2996 }
fafee734 2997
4bac9ae4
CS
2998 Newx(buffer, len, char);
2999 buffer_end = retval = buffer + len;
3000
3001 /* Working backwards */
3002 *--retval = '\0';
3003 *--retval = ')';
3004 do {
3005 *--retval = PL_hexdigit[addr & 15];
3006 } while (addr >>= 4);
3007 *--retval = 'x';
3008 *--retval = '0';
3009 *--retval = '(';
3010
3011 retval -= typelen;
3012 memcpy(retval, typestr, typelen);
3013
3014 if (stashname) {
3015 *--retval = '=';
3016 retval -= stashnamelen;
3017 memcpy(retval, stashname, stashnamelen);
c080367d 3018 }
4bac9ae4
CS
3019 /* retval may not necessarily have reached the start of the
3020 buffer here. */
3021 assert (retval >= buffer);
3022
3023 len = buffer_end - retval - 1; /* -1 for that \0 */
463ee0b2 3024 }
cdb061a3 3025 if (lp)
4bac9ae4
CS
3026 *lp = len;
3027 SAVEFREEPV(buffer);
3028 return retval;
79072805 3029 }
79072805 3030 }
4bac9ae4
CS
3031
3032 if (SvPOKp(sv)) {
3033 if (lp)
3034 *lp = SvCUR(sv);
3035 if (flags & SV_MUTABLE_RETURN)
3036 return SvPVX_mutable(sv);
3037 if (flags & SV_CONST_RETURN)
3038 return (char *)SvPVX_const(sv);
3039 return SvPVX(sv);
3040 }
3041
3042 if (SvIOK(sv)) {
28e5dec8
JH
3043 /* I'm assuming that if both IV and NV are equally valid then
3044 converting the IV is going to be more efficient */
e1ec3a88 3045 const U32 isUIOK = SvIsUV(sv);
28e5dec8
JH
3046 char buf[TYPE_CHARS(UV)];
3047 char *ebuf, *ptr;
97a130b8 3048 STRLEN len;
28e5dec8
JH
3049
3050 if (SvTYPE(sv) < SVt_PVIV)
3051 sv_upgrade(sv, SVt_PVIV);
4ea1d550 3052 ptr = uiv_2buf(buf, SvIVX(sv), SvUVX(sv), isUIOK, &ebuf);
97a130b8 3053 len = ebuf - ptr;
5902b6a9 3054 /* inlined from sv_setpvn */
97a130b8
NC
3055 s = SvGROW_mutable(sv, len + 1);
3056 Move(ptr, s, len, char);
3057 s += len;
28e5dec8 3058 *s = '\0';
b127e37e 3059 SvPOK_on(sv);
28e5dec8 3060 }
4bac9ae4 3061 else if (SvNOK(sv)) {
79072805
LW
3062 if (SvTYPE(sv) < SVt_PVNV)
3063 sv_upgrade(sv, SVt_PVNV);
128eeacb
DD
3064 if (SvNVX(sv) == 0.0
3065#if defined(NAN_COMPARE_BROKEN) && defined(Perl_isnan)
0f83c5a4 3066 /* XXX Create SvNVXeq(sv, x)? Or just SvNVXzero(sv)? */
128eeacb
DD
3067 && !Perl_isnan(SvNVX(sv))
3068#endif
3069 ) {
29912d93
NC
3070 s = SvGROW_mutable(sv, 2);
3071 *s++ = '0';
3072 *s = '\0';
3073 } else {
5e85836e 3074 STRLEN len;
fb8cdbc5 3075 STRLEN size = 5; /* "-Inf\0" */
0c7e610f 3076
fb8cdbc5 3077 s = SvGROW_mutable(sv, size);
5e85836e 3078 len = S_infnan_2pv(SvNVX(sv), s, size);
fb8cdbc5 3079 if (len > 0) {
0c7e610f 3080 s += len;
fb8cdbc5
JH
3081 SvPOK_on(sv);
3082 }
0c7e610f 3083 else {
0c7e610f 3084 /* some Xenix systems wipe out errno here */
fb8cdbc5
JH
3085 dSAVE_ERRNO;
3086
3840bff0
JH
3087 size =
3088 1 + /* sign */
3089 1 + /* "." */
3090 NV_DIG +
3091 1 + /* "e" */
3092 1 + /* sign */
3093 5 + /* exponent digits */
3094 1 + /* \0 */
3095 2; /* paranoia */
b127e37e 3096
fb8cdbc5 3097 s = SvGROW_mutable(sv, size);
b127e37e 3098#ifndef USE_LOCALE_NUMERIC
a4eca1d4
JH
3099 SNPRINTF_G(SvNVX(sv), s, SvLEN(sv), NV_DIG);
3100
0c7e610f
JH
3101 SvPOK_on(sv);
3102#else
28acfe03 3103 {
3840bff0 3104 bool local_radix;
0c7e610f 3105 DECLARE_STORE_LC_NUMERIC_SET_TO_NEEDED();
3840bff0
JH
3106
3107 local_radix =
3108 PL_numeric_local &&
3109 PL_numeric_radix_sv &&
3110 SvUTF8(PL_numeric_radix_sv);
3111 if (local_radix && SvLEN(PL_numeric_radix_sv) > 1) {
3112 size += SvLEN(PL_numeric_radix_sv) - 1;
3113 s = SvGROW_mutable(sv, size);
3114 }
3115
a4eca1d4 3116 SNPRINTF_G(SvNVX(sv), s, SvLEN(sv), NV_DIG);
0c7e610f
JH
3117
3118 /* If the radix character is UTF-8, and actually is in the
3119 * output, turn on the UTF-8 flag for the scalar */
3840bff0
JH
3120 if (local_radix &&
3121 instr(s, SvPVX_const(PL_numeric_radix_sv))) {
3122 SvUTF8_on(sv);
3123 }
3124
0c7e610f 3125 RESTORE_LC_NUMERIC();
28acfe03 3126 }
68e8f474 3127
0c7e610f
JH
3128 /* We don't call SvPOK_on(), because it may come to
3129 * pass that the locale changes so that the
3130 * stringification we just did is no longer correct. We
3131 * will have to re-stringify every time it is needed */
b127e37e 3132#endif
0c7e610f
JH
3133 RESTORE_ERRNO;
3134 }
3135 while (*s) s++;
bbce6d69 3136 }
79072805 3137 }
4bac9ae4
CS
3138 else if (isGV_with_GP(sv)) {
3139 GV *const gv = MUTABLE_GV(sv);
3140 SV *const buffer = sv_newmortal();
8d1c3e26 3141
4bac9ae4 3142 gv_efullname3(buffer, gv, "*");
180488f8 3143
4bac9ae4
CS
3144 assert(SvPOK(buffer));
3145 if (SvUTF8(buffer))
3146 SvUTF8_on(sv);
3147 if (lp)
3148 *lp = SvCUR(buffer);
3149 return SvPVX(buffer);
3150 }
8d919b0a
FC
3151 else if (isREGEXP(sv)) {
3152 if (lp) *lp = RX_WRAPLEN((REGEXP *)sv);
3153 return RX_WRAPPED((REGEXP *)sv);
3154 }
4bac9ae4 3155 else {
cdb061a3 3156 if (lp)
00b6aa41 3157 *lp = 0;
9f621bb0
NC
3158 if (flags & SV_UNDEF_RETURNS_NULL)
3159 return NULL;
4f62cd62 3160 if (!PL_localizing && ckWARN(WARN_UNINITIALIZED))
9f621bb0 3161 report_uninit(sv);
4bac9ae4
CS
3162 /* Typically the caller expects that sv_any is not NULL now. */
3163 if (!SvREADONLY(sv) && SvTYPE(sv) < SVt_PV)
25da4f38 3164 sv_upgrade(sv, SVt_PV);
73d840c0 3165 return (char *)"";
79072805 3166 }
4bac9ae4 3167
cdb061a3 3168 {
823a54a3 3169 const STRLEN len = s - SvPVX_const(sv);
cdb061a3
NC
3170 if (lp)
3171 *lp = len;
3172 SvCUR_set(sv, len);
3173 }
1d7c1841 3174 DEBUG_c(PerlIO_printf(Perl_debug_log, "0x%"UVxf" 2pv(%s)\n",
3f7c398e 3175 PTR2UV(sv),SvPVX_const(sv)));
4d84ee25
NC
3176 if (flags & SV_CONST_RETURN)
3177 return (char *)SvPVX_const(sv);
10516c54
NC
3178 if (flags & SV_MUTABLE_RETURN)
3179 return SvPVX_mutable(sv);
463ee0b2
LW
3180 return SvPVX(sv);
3181}
3182
645c22ef 3183/*
6050d10e
JP
3184=for apidoc sv_copypv
3185
3186Copies a stringified representation of the source SV into the
3187destination SV. Automatically performs any necessary mg_get and
54f0641b 3188coercion of numeric values into strings. Guaranteed to preserve
2575c402 3189UTF8 flag even from overloaded objects. Similar in nature to
54f0641b
NIS
3190sv_2pv[_flags] but operates directly on an SV instead of just the
3191string. Mostly uses sv_2pv_flags to do its work, except when that
6050d10e
JP
3192would lose the UTF-8'ness of the PV.
3193
4bac9ae4
CS
3194=for apidoc sv_copypv_nomg
3195
3196Like sv_copypv, but doesn't invoke get magic first.
3197
3198=for apidoc sv_copypv_flags
3199
3200Implementation of sv_copypv and sv_copypv_nomg. Calls get magic iff flags
3201include SV_GMAGIC.
3202
6050d10e
JP
3203=cut
3204*/
3205
3206void
5aaab254 3207Perl_sv_copypv(pTHX_ SV *const dsv, SV *const ssv)
6050d10e 3208{
4bac9ae4
CS
3209 PERL_ARGS_ASSERT_SV_COPYPV;
3210
3211 sv_copypv_flags(dsv, ssv, 0);
3212}
3213
3214void
5aaab254 3215Perl_sv_copypv_flags(pTHX_ SV *const dsv, SV *const ssv, const I32 flags)
4bac9ae4 3216{
446eaa42 3217 STRLEN len;
4bac9ae4 3218 const char *s;
7918f24d 3219
4bac9ae4 3220 PERL_ARGS_ASSERT_SV_COPYPV_FLAGS;
7918f24d 3221
c77ed9ca 3222 s = SvPV_flags_const(ssv,len,(flags & SV_GMAGIC));
cb50f42d 3223 sv_setpvn(dsv,s,len);
446eaa42 3224 if (SvUTF8(ssv))
cb50f42d 3225 SvUTF8_on(dsv);
446eaa42 3226 else
cb50f42d 3227 SvUTF8_off(dsv);
6050d10e
JP
3228}
3229
3230/*
645c22ef
DM
3231=for apidoc sv_2pvbyte
3232
3233Return a pointer to the byte-encoded representation of the SV, and set *lp
1e54db1a 3234to its length. May cause the SV to be downgraded from UTF-8 as a
645c22ef
DM
3235side-effect.
3236
3237Usually accessed via the C<SvPVbyte> macro.
3238
3239=cut
3240*/
3241
7340a771 3242char *
5aaab254 3243Perl_sv_2pvbyte(pTHX_ SV *sv, STRLEN *const lp)
7340a771 3244{
7918f24d
NC
3245 PERL_ARGS_ASSERT_SV_2PVBYTE;
3246
48120f8f 3247 SvGETMAGIC(sv);
4499db73
FC
3248 if (((SvREADONLY(sv) || SvFAKE(sv)) && !SvIsCOW(sv))
3249 || isGV_with_GP(sv) || SvROK(sv)) {
a901b181 3250 SV *sv2 = sv_newmortal();
48120f8f 3251 sv_copypv_nomg(sv2,sv);
a901b181
FC
3252 sv = sv2;
3253 }
0875d2fe 3254 sv_utf8_downgrade(sv,0);
71eb6d8c 3255 return lp ? SvPV_nomg(sv,*lp) : SvPV_nomg_nolen(sv);
7340a771
GS
3256}
3257
645c22ef 3258/*
035cbb0e
RGS
3259=for apidoc sv_2pvutf8
3260
3261Return a pointer to the UTF-8-encoded representation of the SV, and set *lp
3262to its length. May cause the SV to be upgraded to UTF-8 as a side-effect.
3263
3264Usually accessed via the C<SvPVutf8> macro.
3265
3266=cut
3267*/
645c22ef 3268
7340a771 3269char *
5aaab254 3270Perl_sv_2pvutf8(pTHX_ SV *sv, STRLEN *const lp)
7340a771 3271{
7918f24d
NC
3272 PERL_ARGS_ASSERT_SV_2PVUTF8;
3273
4499db73
FC
3274 if (((SvREADONLY(sv) || SvFAKE(sv)) && !SvIsCOW(sv))
3275 || isGV_with_GP(sv) || SvROK(sv))
fe46cbda 3276 sv = sv_mortalcopy(sv);
4bac9ae4
CS
3277 else
3278 SvGETMAGIC(sv);
3279 sv_utf8_upgrade_nomg(sv);
c3ec315f 3280 return lp ? SvPV_nomg(sv,*lp) : SvPV_nomg_nolen(sv);
7340a771 3281}
1c846c1f 3282
7ee2227d 3283
645c22ef
DM
3284/*
3285=for apidoc sv_2bool
3286
06c841cf
FC
3287This macro is only used by sv_true() or its macro equivalent, and only if
3288the latter's argument is neither SvPOK, SvIOK nor SvNOK.
3289It calls sv_2bool_flags with the SV_GMAGIC flag.
3290
3291=for apidoc sv_2bool_flags
3292
3293This function is only used by sv_true() and friends, and only if
fde67290 3294the latter's argument is neither SvPOK, SvIOK nor SvNOK. If the flags
06c841cf
FC
3295contain SV_GMAGIC, then it does an mg_get() first.
3296
645c22ef
DM
3297
3298=cut
3299*/
3300
463ee0b2 3301bool
9d176cd8 3302Perl_sv_2bool_flags(pTHX_ SV *sv, I32 flags)
463ee0b2 3303{
06c841cf 3304 PERL_ARGS_ASSERT_SV_2BOOL_FLAGS;
7918f24d 3305
9d176cd8 3306 restart:
06c841cf 3307 if(flags & SV_GMAGIC) SvGETMAGIC(sv);
463ee0b2 3308
a0d0e21e
LW
3309 if (!SvOK(sv))
3310 return 0;
3311 if (SvROK(sv)) {
fabdb6c0 3312 if (SvAMAGIC(sv)) {
31d632c3 3313 SV * const tmpsv = AMG_CALLunary(sv, bool__amg);
9d176cd8
DD
3314 if (tmpsv && (!SvROK(tmpsv) || (SvRV(tmpsv) != SvRV(sv)))) {
3315 bool svb;
3316 sv = tmpsv;
3317 if(SvGMAGICAL(sv)) {
3318 flags = SV_GMAGIC;
3319 goto restart; /* call sv_2bool */
3320 }
3321 /* expanded SvTRUE_common(sv, (flags = 0, goto restart)) */
3322 else if(!SvOK(sv)) {
3323 svb = 0;
3324 }
3325 else if(SvPOK(sv)) {
3326 svb = SvPVXtrue(sv);
3327 }
3328 else if((SvFLAGS(sv) & (SVf_IOK|SVf_NOK))) {
3329 svb = (SvIOK(sv) && SvIVX(sv) != 0)
659c4b96 3330 || (SvNOK(sv) && SvNVX(sv) != 0.0);
9d176cd8
DD
3331 }
3332 else {
3333 flags = 0;
3334 goto restart; /* call sv_2bool_nomg */
3335 }
3336 return cBOOL(svb);
3337 }
fabdb6c0
AL
3338 }
3339 return SvRV(sv) != 0;
a0d0e21e 3340 }
85b7d9b3
FC
3341 if (isREGEXP(sv))
3342 return
3343 RX_WRAPLEN(sv) > 1 || (RX_WRAPLEN(sv) && *RX_WRAPPED(sv) != '0');
4bac9ae4 3344 return SvTRUE_common(sv, isGV_with_GP(sv) ? 1 : 0);
79072805
LW
3345}
3346
c461cf8f
JH
3347/*
3348=for apidoc sv_utf8_upgrade
3349
78ea37eb 3350Converts the PV of an SV to its UTF-8-encoded form.
645c22ef 3351Forces the SV to string form if it is not already.
2bbc8d55 3352Will C<mg_get> on C<sv> if appropriate.
4411f3b6 3353Always sets the SvUTF8 flag to avoid future validity checks even
2bbc8d55
SP
3354if the whole string is the same in UTF-8 as not.
3355Returns the number of bytes in the converted string
c461cf8f 3356
0efd0472 3357This is not a general purpose byte encoding to Unicode interface:
13a6c0e0
JH
3358use the Encode extension for that.
3359
fe749c9a
KW
3360=for apidoc sv_utf8_upgrade_nomg
3361
fde67290 3362Like sv_utf8_upgrade, but doesn't do magic on C<sv>.
fe749c9a 3363
8d6d96c1
HS
3364=for apidoc sv_utf8_upgrade_flags
3365
78ea37eb 3366Converts the PV of an SV to its UTF-8-encoded form.
645c22ef 3367Forces the SV to string form if it is not already.
8d6d96c1 3368Always sets the SvUTF8 flag to avoid future validity checks even
960b0271
FC
3369if all the bytes are invariant in UTF-8.
3370If C<flags> has C<SV_GMAGIC> bit set,
2bbc8d55 3371will C<mg_get> on C<sv> if appropriate, else not.
2a590426
KW
3372
3373If C<flags> has SV_FORCE_UTF8_UPGRADE set, this function assumes that the PV
3374will expand when converted to UTF-8, and skips the extra work of checking for
3375that. Typically this flag is used by a routine that has already parsed the
3376string and found such characters, and passes this information on so that the
3377work doesn't have to be repeated.
3378
3379Returns the number of bytes in the converted string.
8d6d96c1 3380
0efd0472 3381This is not a general purpose byte encoding to Unicode interface:
13a6c0e0
JH
3382use the Encode extension for that.
3383
2a590426 3384=for apidoc sv_utf8_upgrade_flags_grow
b3ab6785 3385
2a590426
KW
3386Like sv_utf8_upgrade_flags, but has an additional parameter C<extra>, which is
3387the number of unused bytes the string of 'sv' is guaranteed to have free after
3388it upon return. This allows the caller to reserve extra space that it intends
3389to fill, to avoid extra grows.
b3ab6785 3390
2a590426
KW
3391C<sv_utf8_upgrade>, C<sv_utf8_upgrade_nomg>, and C<sv_utf8_upgrade_flags>
3392are implemented in terms of this function.
3393
3394Returns the number of bytes in the converted string (not including the spares).
3395
3396=cut
b3ab6785
KW
3397
3398(One might think that the calling routine could pass in the position of the
2a590426
KW
3399first variant character when it has set SV_FORCE_UTF8_UPGRADE, so it wouldn't
3400have to be found again. But that is not the case, because typically when the
3401caller is likely to use this flag, it won't be calling this routine unless it
3402finds something that won't fit into a byte. Otherwise it tries to not upgrade
3403and just use bytes. But some things that do fit into a byte are variants in
3404utf8, and the caller may not have been keeping track of these.)
b3ab6785 3405
6602b933
KW
3406If the routine itself changes the string, it adds a trailing C<NUL>. Such a
3407C<NUL> isn't guaranteed due to having other routines do the work in some input
3408cases, or if the input is already flagged as being in utf8.
b3ab6785
KW
3409
3410The speed of this could perhaps be improved for many cases if someone wanted to
3411write a fast function that counts the number of variant characters in a string,
3412especially if it could return the position of the first one.
3413
8d6d96c1
HS
3414*/
3415
3416STRLEN
5aaab254 3417Perl_sv_utf8_upgrade_flags_grow(pTHX_ SV *const sv, const I32 flags, STRLEN extra)
8d6d96c1 3418{
b3ab6785 3419 PERL_ARGS_ASSERT_SV_UTF8_UPGRADE_FLAGS_GROW;
7918f24d 3420
808c356f
RGS
3421 if (sv == &PL_sv_undef)
3422 return 0;
892f9127 3423 if (!SvPOK_nog(sv)) {
e0e62c2a 3424 STRLEN len = 0;
d52b7888
NC
3425 if (SvREADONLY(sv) && (SvPOKp(sv) || SvIOKp(sv) || SvNOKp(sv))) {
3426 (void) sv_2pv_flags(sv,&len, flags);
b3ab6785
KW
3427 if (SvUTF8(sv)) {
3428 if (extra) SvGROW(sv, SvCUR(sv) + extra);
d52b7888 3429 return len;
b3ab6785 3430 }
d52b7888 3431 } else {
33fb6f35 3432 (void) SvPV_force_flags(sv,len,flags & SV_GMAGIC);
d52b7888 3433 }
e0e62c2a 3434 }
4411f3b6 3435
f5cee72b 3436 if (SvUTF8(sv)) {
b3ab6785 3437 if (extra) SvGROW(sv, SvCUR(sv) + extra);
5fec3b1d 3438 return SvCUR(sv);
f5cee72b 3439 }
5fec3b1d 3440
765f542d 3441 if (SvIsCOW(sv)) {
c56ed9f6 3442 S_sv_uncow(aTHX_ sv, 0);
db42d148
NIS
3443 }
3444
b3ab6785 3445 if (PL_encoding && !(flags & SV_UTF8_NO_ENCODING)) {
799ef3cb 3446 sv_recode_to_utf8(sv, PL_encoding);
b3ab6785
KW
3447 if (extra) SvGROW(sv, SvCUR(sv) + extra);
3448 return SvCUR(sv);
3449 }
3450
4e93345f
KW
3451 if (SvCUR(sv) == 0) {
3452 if (extra) SvGROW(sv, extra);
3453 } else { /* Assume Latin-1/EBCDIC */
c4e7c712 3454 /* This function could be much more efficient if we
2bbc8d55 3455 * had a FLAG in SVs to signal if there are any variant
c4e7c712 3456 * chars in the PV. Given that there isn't such a flag
b3ab6785
KW
3457 * make the loop as fast as possible (although there are certainly ways
3458 * to speed this up, eg. through vectorization) */
3459 U8 * s = (U8 *) SvPVX_const(sv);
3460 U8 * e = (U8 *) SvEND(sv);
3461 U8 *t = s;
3462 STRLEN two_byte_count = 0;
c4e7c712 3463
b3ab6785
KW
3464 if (flags & SV_FORCE_UTF8_UPGRADE) goto must_be_utf8;
3465
3466 /* See if really will need to convert to utf8. We mustn't rely on our
3467 * incoming SV being well formed and having a trailing '\0', as certain
3468 * code in pp_formline can send us partially built SVs. */
3469
c4e7c712 3470 while (t < e) {
53c1dcc0 3471 const U8 ch = *t++;
6f2d5cbc 3472 if (NATIVE_BYTE_IS_INVARIANT(ch)) continue;
b3ab6785
KW
3473
3474 t--; /* t already incremented; re-point to first variant */
3475 two_byte_count = 1;
3476 goto must_be_utf8;
c4e7c712 3477 }
b3ab6785
KW
3478
3479 /* utf8 conversion not needed because all are invariants. Mark as
3480 * UTF-8 even if no variant - saves scanning loop */
c4e7c712 3481 SvUTF8_on(sv);
7f0bfbea 3482 if (extra) SvGROW(sv, SvCUR(sv) + extra);
b3ab6785
KW
3483 return SvCUR(sv);
3484
3485must_be_utf8:
3486
3487 /* Here, the string should be converted to utf8, either because of an
3488 * input flag (two_byte_count = 0), or because a character that
3489 * requires 2 bytes was found (two_byte_count = 1). t points either to
3490 * the beginning of the string (if we didn't examine anything), or to
3491 * the first variant. In either case, everything from s to t - 1 will
3492 * occupy only 1 byte each on output.
3493 *
3494 * There are two main ways to convert. One is to create a new string
3495 * and go through the input starting from the beginning, appending each
3496 * converted value onto the new string as we go along. It's probably
3497 * best to allocate enough space in the string for the worst possible
3498 * case rather than possibly running out of space and having to
3499 * reallocate and then copy what we've done so far. Since everything
3500 * from s to t - 1 is invariant, the destination can be initialized
3501 * with these using a fast memory copy
3502 *
3503 * The other way is to figure out exactly how big the string should be
3504 * by parsing the entire input. Then you don't have to make it big
3505 * enough to handle the worst possible case, and more importantly, if
3506 * the string you already have is large enough, you don't have to
3507 * allocate a new string, you can copy the last character in the input
3508 * string to the final position(s) that will be occupied by the
3509 * converted string and go backwards, stopping at t, since everything
3510 * before that is invariant.
3511 *
3512 * There are advantages and disadvantages to each method.
3513 *
3514 * In the first method, we can allocate a new string, do the memory
3515 * copy from the s to t - 1, and then proceed through the rest of the
3516 * string byte-by-byte.
3517 *
3518 * In the second method, we proceed through the rest of the input
3519 * string just calculating how big the converted string will be. Then
3520 * there are two cases:
3521 * 1) if the string has enough extra space to handle the converted
3522 * value. We go backwards through the string, converting until we
3523 * get to the position we are at now, and then stop. If this
3524 * position is far enough along in the string, this method is
3525 * faster than the other method. If the memory copy were the same
3526 * speed as the byte-by-byte loop, that position would be about
3527 * half-way, as at the half-way mark, parsing to the end and back
3528 * is one complete string's parse, the same amount as starting
3529 * over and going all the way through. Actually, it would be
3530 * somewhat less than half-way, as it's faster to just count bytes
3531 * than to also copy, and we don't have the overhead of allocating
3532 * a new string, changing the scalar to use it, and freeing the
3533 * existing one. But if the memory copy is fast, the break-even
3534 * point is somewhere after half way. The counting loop could be
3535 * sped up by vectorization, etc, to move the break-even point
3536 * further towards the beginning.
3537 * 2) if the string doesn't have enough space to handle the converted
3538 * value. A new string will have to be allocated, and one might
3539 * as well, given that, start from the beginning doing the first
3540 * method. We've spent extra time parsing the string and in
3541 * exchange all we've gotten is that we know precisely how big to
3542 * make the new one. Perl is more optimized for time than space,
3543 * so this case is a loser.
3544 * So what I've decided to do is not use the 2nd method unless it is
3545 * guaranteed that a new string won't have to be allocated, assuming
3546 * the worst case. I also decided not to put any more conditions on it
3547 * than this, for now. It seems likely that, since the worst case is
3548 * twice as big as the unknown portion of the string (plus 1), we won't
3549 * be guaranteed enough space, causing us to go to the first method,
3550 * unless the string is short, or the first variant character is near
3551 * the end of it. In either of these cases, it seems best to use the
3552 * 2nd method. The only circumstance I can think of where this would
3553 * be really slower is if the string had once had much more data in it
3554 * than it does now, but there is still a substantial amount in it */
3555
3556 {
3557 STRLEN invariant_head = t - s;
3558 STRLEN size = invariant_head + (e - t) * 2 + 1 + extra;
3559 if (SvLEN(sv) < size) {
3560
3561 /* Here, have decided to allocate a new string */
3562
3563 U8 *dst;
3564 U8 *d;
3565
3566 Newx(dst, size, U8);
3567
3568 /* If no known invariants at the beginning of the input string,
3569 * set so starts from there. Otherwise, can use memory copy to
3570 * get up to where we are now, and then start from here */
3571
5b26a7b3 3572 if (invariant_head == 0) {
b3ab6785
KW
3573 d = dst;
3574 } else {
3575 Copy(s, dst, invariant_head, char);
3576 d = dst + invariant_head;
3577 }
3578
3579 while (t < e) {
55d09dc8
KW
3580 append_utf8_from_native_byte(*t, &d);
3581 t++;
b3ab6785
KW
3582 }
3583 *d = '\0';
3584 SvPV_free(sv); /* No longer using pre-existing string */
3585 SvPV_set(sv, (char*)dst);
3586 SvCUR_set(sv, d - dst);
3587 SvLEN_set(sv, size);
3588 } else {
3589
3590 /* Here, have decided to get the exact size of the string.
3591 * Currently this happens only when we know that there is
3592 * guaranteed enough space to fit the converted string, so
3593 * don't have to worry about growing. If two_byte_count is 0,
3594 * then t points to the first byte of the string which hasn't
3595 * been examined yet. Otherwise two_byte_count is 1, and t
3596 * points to the first byte in the string that will expand to
3597 * two. Depending on this, start examining at t or 1 after t.
3598 * */
3599