xref: /openbsd-src/gnu/usr.bin/perl/op.h (revision 50b7afb2c2c0993b0894d4e34bf857cb13ed9c80)
1 /*    op.h
2  *
3  *    Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
4  *    2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 by Larry Wall and others
5  *
6  *    You may distribute under the terms of either the GNU General Public
7  *    License or the Artistic License, as specified in the README file.
8  *
9  */
10 
11 /*
12  * The fields of BASEOP are:
13  *	op_next		Pointer to next ppcode to execute after this one.
14  *			(Top level pre-grafted op points to first op,
15  *			but this is replaced when op is grafted in, when
16  *			this op will point to the real next op, and the new
17  *			parent takes over role of remembering starting op.)
18  *	op_ppaddr	Pointer to current ppcode's function.
19  *	op_type		The type of the operation.
20  *	op_opt		Whether or not the op has been optimised by the
21  *			peephole optimiser.
22  *	op_slabbed	allocated via opslab
23  *	op_static	tell op_free() to skip PerlMemShared_free(), when
24  *                      !op_slabbed.
25  *	op_savefree	on savestack via SAVEFREEOP
26  *	op_spare	Three spare bits
27  *	op_flags	Flags common to all operations.  See OPf_* below.
28  *	op_private	Flags peculiar to a particular operation (BUT,
29  *			by default, set to the number of children until
30  *			the operation is privatized by a check routine,
31  *			which may or may not check number of children).
32  */
33 #include "op_reg_common.h"
34 
35 #define OPCODE U16
36 
37 #ifdef PERL_MAD
38 #  define MADPROP_IN_BASEOP	MADPROP*	op_madprop;
39 #else
40 #  define MADPROP_IN_BASEOP
41 #endif
42 
43 typedef PERL_BITFIELD16 Optype;
44 
45 #ifdef BASEOP_DEFINITION
46 #define BASEOP BASEOP_DEFINITION
47 #else
48 #define BASEOP				\
49     OP*		op_next;		\
50     OP*		op_sibling;		\
51     OP*		(*op_ppaddr)(pTHX);	\
52     MADPROP_IN_BASEOP			\
53     PADOFFSET	op_targ;		\
54     PERL_BITFIELD16 op_type:9;		\
55     PERL_BITFIELD16 op_opt:1;		\
56     PERL_BITFIELD16 op_slabbed:1;	\
57     PERL_BITFIELD16 op_savefree:1;	\
58     PERL_BITFIELD16 op_static:1;	\
59     PERL_BITFIELD16 op_spare:3;		\
60     U8		op_flags;		\
61     U8		op_private;
62 #endif
63 
64 /* If op_type:9 is changed to :10, also change PUSHEVAL in cop.h.
65    Also, if the type of op_type is ever changed (e.g. to PERL_BITFIELD32)
66    then all the other bit-fields before/after it should change their
67    types too to let VC pack them into the same 4 byte integer.*/
68 
69 /* for efficiency, requires OPf_WANT_VOID == G_VOID etc */
70 #define OP_GIMME(op,dfl) \
71 	(((op)->op_flags & OPf_WANT) ? ((op)->op_flags & OPf_WANT) : dfl)
72 
73 #define OP_GIMME_REVERSE(flags)	((flags) & G_WANT)
74 
75 /*
76 =head1 "Gimme" Values
77 
78 =for apidoc Amn|U32|GIMME_V
79 The XSUB-writer's equivalent to Perl's C<wantarray>.  Returns C<G_VOID>,
80 C<G_SCALAR> or C<G_ARRAY> for void, scalar or list context,
81 respectively. See L<perlcall> for a usage example.
82 
83 =for apidoc Amn|U32|GIMME
84 A backward-compatible version of C<GIMME_V> which can only return
85 C<G_SCALAR> or C<G_ARRAY>; in a void context, it returns C<G_SCALAR>.
86 Deprecated.  Use C<GIMME_V> instead.
87 
88 =cut
89 */
90 
91 #define GIMME_V		OP_GIMME(PL_op, block_gimme())
92 
93 /* Public flags */
94 
95 #define OPf_WANT	3	/* Mask for "want" bits: */
96 #define  OPf_WANT_VOID	 1	/*   Want nothing */
97 #define  OPf_WANT_SCALAR 2	/*   Want single value */
98 #define  OPf_WANT_LIST	 3	/*   Want list of any length */
99 #define OPf_KIDS	4	/* There is a firstborn child. */
100 #define OPf_PARENS	8	/* This operator was parenthesized. */
101 				/*  (Or block needs explicit scope entry.) */
102 #define OPf_REF		16	/* Certified reference. */
103 				/*  (Return container, not containee). */
104 #define OPf_MOD		32	/* Will modify (lvalue). */
105 #define OPf_STACKED	64	/* Some arg is arriving on the stack. */
106 #define OPf_SPECIAL	128	/* Do something weird for this op: */
107 				/*  On local LVAL, don't init local value. */
108 				/*  On OP_SORT, subroutine is inlined. */
109 				/*  On OP_NOT, inversion was implicit. */
110 				/*  On OP_LEAVE, don't restore curpm. */
111 				/*  On truncate, we truncate filehandle */
112 				/*  On control verbs, we saw no label */
113 				/*  On flipflop, we saw ... instead of .. */
114 				/*  On UNOPs, saw bare parens, e.g. eof(). */
115 				/*  On OP_ENTERSUB || OP_NULL, saw a "do". */
116 				/*  On OP_EXISTS, treat av as av, not avhv.  */
117 				/*  On OP_(ENTER|LEAVE)EVAL, don't clear $@ */
118                                 /*  On pushre, rx is used as part of split, e.g. split " " */
119 				/*  On regcomp, "use re 'eval'" was in scope */
120 				/*  On OP_READLINE, was <$filehandle> */
121 				/*  On RV2[ACGHS]V, don't create GV--in
122 				    defined()*/
123 				/*  On OP_DBSTATE, indicates breakpoint
124 				 *    (runtime property) */
125 				/*  On OP_REQUIRE, was seen as CORE::require */
126 				/*  On OP_(ENTER|LEAVE)WHEN, there's
127 				    no condition */
128 				/*  On OP_SMARTMATCH, an implicit smartmatch */
129 				/*  On OP_ANONHASH and OP_ANONLIST, create a
130 				    reference to the new anon hash or array */
131 				/*  On OP_HELEM and OP_HSLICE, localization will be followed
132 				    by assignment, so do not wipe the target if it is special
133 				    (e.g. a glob or a magic SV) */
134 				/*  On OP_MATCH, OP_SUBST & OP_TRANS, the
135 				    operand of a logical or conditional
136 				    that was optimised away, so it should
137 				    not be bound via =~ */
138 				/*  On OP_CONST, from a constant CV */
139 				/*  On OP_GLOB, two meanings:
140 				    - Before ck_glob, called as CORE::glob
141 				    - After ck_glob, use Perl glob function
142 			         */
143                                 /*  On OP_PADRANGE, push @_ */
144 
145 /* old names; don't use in new code, but don't break them, either */
146 #define OPf_LIST	OPf_WANT_LIST
147 #define OPf_KNOW	OPf_WANT
148 
149 #define GIMME \
150 	  (PL_op->op_flags & OPf_WANT					\
151 	   ? ((PL_op->op_flags & OPf_WANT) == OPf_WANT_LIST		\
152 	      ? G_ARRAY							\
153 	      : G_SCALAR)						\
154 	   : dowantarray())
155 
156 /* Lower bits of op_private often carry the number of arguments, as
157  * set by newBINOP, newUNOP and ck_fun */
158 
159 /* NOTE: OP_NEXTSTATE and OP_DBSTATE (i.e. COPs) carry NATIVE_HINTS
160  * in op_private */
161 
162 /* Private for lvalues */
163 #define OPpLVAL_INTRO	128	/* Lvalue must be localized or lvalue sub */
164 
165 /* Private for OPs with TARGLEX */
166   /* (lower bits may carry MAXARG) */
167 #define OPpTARGET_MY		16	/* Target is PADMY. */
168 
169 /* Private for OP_LEAVE, OP_LEAVESUB, OP_LEAVESUBLV and OP_LEAVEWRITE */
170 #define OPpREFCOUNTED		64	/* op_targ carries a refcount */
171 
172 /* Private for OP_AASSIGN */
173 #define OPpASSIGN_COMMON	64	/* Left & right have syms in common. */
174 
175 /* Private for OP_SASSIGN */
176 #define OPpASSIGN_BACKWARDS	64	/* Left & right switched. */
177 #define OPpASSIGN_CV_TO_GV	128	/* Possible optimisation for constants. */
178 
179 /* Private for OP_MATCH and OP_SUBST{,CONT} */
180 #define OPpRUNTIME		64	/* Pattern coming in on the stack */
181 
182 /* Private for OP_TRANS */
183 #define OPpTRANS_FROM_UTF	1
184 #define OPpTRANS_TO_UTF		2
185 #define OPpTRANS_IDENTICAL	4	/* right side is same as left */
186 #define OPpTRANS_SQUASH		8
187     /* 16 is used for OPpTARGET_MY */
188 #define OPpTRANS_COMPLEMENT	32
189 #define OPpTRANS_GROWS		64
190 #define OPpTRANS_DELETE		128
191 #define OPpTRANS_ALL	(OPpTRANS_FROM_UTF|OPpTRANS_TO_UTF|OPpTRANS_IDENTICAL|OPpTRANS_SQUASH|OPpTRANS_COMPLEMENT|OPpTRANS_GROWS|OPpTRANS_DELETE)
192 
193 /* Private for OP_REPEAT */
194 #define OPpREPEAT_DOLIST	64	/* List replication. */
195 
196 /* Private for OP_RV2GV, OP_RV2SV, OP_AELEM, OP_HELEM, OP_PADSV */
197 #define OPpDEREF		(32|64)	/* autovivify: Want ref to something: */
198 #define OPpDEREF_AV		32	/*   Want ref to AV. */
199 #define OPpDEREF_HV		64	/*   Want ref to HV. */
200 #define OPpDEREF_SV		(32|64)	/*   Want ref to SV. */
201 
202   /* OP_ENTERSUB only */
203 #define OPpENTERSUB_DB		16	/* Debug subroutine. */
204 #define OPpENTERSUB_HASTARG	4	/* Called from OP tree. */
205 #define OPpENTERSUB_INARGS	1	/* Lval used as arg to a sub. */
206 /* used by OPpDEREF             (32|64) */
207 /* used by HINT_STRICT_SUBS     2          */
208   /* Mask for OP_ENTERSUB flags, the absence of which must be propagated
209      in dynamic context */
210 #define OPpENTERSUB_LVAL_MASK (OPpLVAL_INTRO|OPpENTERSUB_INARGS)
211 
212   /* OP_RV2CV only */
213 #define OPpENTERSUB_AMPER	8	/* Used & form to call. */
214 #define OPpENTERSUB_NOPAREN	128	/* bare sub call (without parens) */
215 #define OPpMAY_RETURN_CONSTANT	1	/* If a constant sub, return the constant */
216 
217   /* OP_GV only */
218 #define OPpEARLY_CV		32	/* foo() called before sub foo was parsed */
219   /* OP_?ELEM only */
220 #define OPpLVAL_DEFER		16	/* Defer creation of array/hash elem */
221   /* OP_RV2[SAH]V, OP_GVSV, OP_ENTERITER only */
222 #define OPpOUR_INTRO		16	/* Variable was in an our() */
223   /* OP_RV2[AGH]V, OP_PAD[AH]V, OP_[AH]ELEM, OP_[AH]SLICE OP_AV2ARYLEN,
224      OP_R?KEYS, OP_SUBSTR, OP_POS, OP_VEC */
225 #define OPpMAYBE_LVSUB		8	/* We might be an lvalue to return */
226   /* OP_RV2HV and OP_PADHV */
227 #define OPpTRUEBOOL		32	/* %hash in (%hash || $foo) in
228 					   void context */
229 #define OPpMAYBE_TRUEBOOL	64	/* %hash in (%hash || $foo) where
230 					   cx is not known till run time */
231 
232   /* OP_SUBSTR only */
233 #define OPpSUBSTR_REPL_FIRST	16	/* 1st arg is replacement string */
234 
235   /* OP_PADSV only */
236 #define OPpPAD_STATE		16	/* is a "state" pad */
237   /* for OP_RV2?V, lower bits carry hints (currently only HINT_STRICT_REFS) */
238 
239   /* OP_PADRANGE only */
240   /* bit 7 is OPpLVAL_INTRO */
241 #define OPpPADRANGE_COUNTMASK	127	/* bits 6..0 hold target range, */
242 #define OPpPADRANGE_COUNTSHIFT	7	/* 7 bits in total */
243 
244   /* OP_RV2GV only */
245 #define OPpDONT_INIT_GV		4	/* Call gv_fetchpv with GV_NOINIT */
246 /* (Therefore will return whatever is currently in the symbol table, not
247    guaranteed to be a PVGV)  */
248 #define OPpALLOW_FAKE		16	/* OK to return fake glob */
249 
250 /* Private for OP_ENTERITER and OP_ITER */
251 #define OPpITER_REVERSED	4	/* for (reverse ...) */
252 #define OPpITER_DEF		8	/* for $_ or for my $_ */
253 
254 /* Private for OP_CONST */
255 #define	OPpCONST_NOVER		2	/* no 6; */
256 #define	OPpCONST_SHORTCIRCUIT	4	/* eg the constant 5 in (5 || foo) */
257 #define	OPpCONST_STRICT		8	/* bareword subject to strict 'subs' */
258 #define OPpCONST_ENTERED	16	/* Has been entered as symbol. */
259 #define OPpCONST_BARE		64	/* Was a bare word (filehandle?). */
260 #define OPpCONST_FOLDED		128	/* Result of constant folding */
261 
262 /* Private for OP_FLIP/FLOP */
263 #define OPpFLIP_LINENUM		64	/* Range arg potentially a line num. */
264 
265 /* Private for OP_LIST */
266 #define OPpLIST_GUESSED		64	/* Guessed that pushmark was needed. */
267 
268 /* Private for OP_DELETE */
269 #define OPpSLICE		64	/* Operating on a list of keys */
270 /* Also OPpLVAL_INTRO (128) */
271 
272 /* Private for OP_EXISTS */
273 #define OPpEXISTS_SUB		64	/* Checking for &sub, not {} or [].  */
274 
275 /* Private for OP_SORT */
276 #define OPpSORT_NUMERIC		1	/* Optimized away { $a <=> $b } */
277 #define OPpSORT_INTEGER		2	/* Ditto while under "use integer" */
278 #define OPpSORT_REVERSE		4	/* Reversed sort */
279 #define OPpSORT_INPLACE		8	/* sort in-place; eg @a = sort @a */
280 #define OPpSORT_DESCEND		16	/* Descending sort */
281 #define OPpSORT_QSORT		32	/* Use quicksort (not mergesort) */
282 #define OPpSORT_STABLE		64	/* Use a stable algorithm */
283 
284 /* Private for OP_REVERSE */
285 #define OPpREVERSE_INPLACE	8	/* reverse in-place (@a = reverse @a) */
286 
287 /* Private for OP_OPEN and OP_BACKTICK */
288 #define OPpOPEN_IN_RAW		16	/* binmode(F,":raw") on input fh */
289 #define OPpOPEN_IN_CRLF		32	/* binmode(F,":crlf") on input fh */
290 #define OPpOPEN_OUT_RAW		64	/* binmode(F,":raw") on output fh */
291 #define OPpOPEN_OUT_CRLF	128	/* binmode(F,":crlf") on output fh */
292 
293 /* Private for OP_EXIT, HUSH also for OP_DIE */
294 #define OPpHUSH_VMSISH		64	/* hush DCL exit msg vmsish mode*/
295 #define OPpEXIT_VMSISH		128	/* exit(0) vs. exit(1) vmsish mode*/
296 
297 /* Private for OP_FTXXX */
298 #define OPpFT_ACCESS		2	/* use filetest 'access' */
299 #define OPpFT_STACKED		4	/* stacked filetest, as "-f" in "-f -x $f" */
300 #define OPpFT_STACKING		8	/* stacking filetest, as "-x" in "-f -x $f" */
301 #define OPpFT_AFTER_t		16	/* previous op was -t */
302 
303 /* Private for OP_(MAP|GREP)(WHILE|START) */
304 #define OPpGREP_LEX		2	/* iterate over lexical $_ */
305 
306 /* Private for OP_ENTEREVAL */
307 #define OPpEVAL_HAS_HH		2	/* Does it have a copy of %^H */
308 #define OPpEVAL_UNICODE		4
309 #define OPpEVAL_BYTES		8
310 #define OPpEVAL_COPHH		16	/* Construct %^H from cop hints */
311 #define OPpEVAL_RE_REPARSING	32	/* eval_sv(..., G_RE_REPARSING) */
312 
313 /* Private for OP_CALLER, OP_WANTARRAY and OP_RUNCV */
314 #define OPpOFFBYONE		128	/* Treat caller(1) as caller(2) */
315 
316 /* Private for OP_COREARGS */
317 /* These must not conflict with OPpDONT_INIT_GV or OPpALLOW_FAKE.
318    See pp.c:S_rv2gv. */
319 #define OPpCOREARGS_DEREF1	1	/* Arg 1 is a handle constructor */
320 #define OPpCOREARGS_DEREF2	2	/* Arg 2 is a handle constructor */
321 #define OPpCOREARGS_SCALARMOD	64	/* \$ rather than \[$@%*] */
322 #define OPpCOREARGS_PUSHMARK	128	/* Call pp_pushmark */
323 
324 /* Private for OP_(LAST|REDO|NEXT|GOTO|DUMP) */
325 #define OPpPV_IS_UTF8		128	/* label is in UTF8 */
326 
327 struct op {
328     BASEOP
329 };
330 
331 struct unop {
332     BASEOP
333     OP *	op_first;
334 };
335 
336 struct binop {
337     BASEOP
338     OP *	op_first;
339     OP *	op_last;
340 };
341 
342 struct logop {
343     BASEOP
344     OP *	op_first;
345     OP *	op_other;
346 };
347 
348 struct listop {
349     BASEOP
350     OP *	op_first;
351     OP *	op_last;
352 };
353 
354 struct pmop {
355     BASEOP
356     OP *	op_first;
357     OP *	op_last;
358 #ifdef USE_ITHREADS
359     IV          op_pmoffset;
360 #else
361     REGEXP *    op_pmregexp;            /* compiled expression */
362 #endif
363     U32         op_pmflags;
364     union {
365 	OP *	op_pmreplroot;		/* For OP_SUBST */
366 #ifdef USE_ITHREADS
367 	PADOFFSET  op_pmtargetoff;	/* For OP_PUSHRE */
368 #else
369 	GV *	op_pmtargetgv;
370 #endif
371     }	op_pmreplrootu;
372     union {
373 	OP *	op_pmreplstart;	/* Only used in OP_SUBST */
374 #ifdef USE_ITHREADS
375 	PADOFFSET op_pmstashoff; /* Only used in OP_MATCH, with PMf_ONCE set */
376 #else
377 	HV *	op_pmstash;
378 #endif
379     }		op_pmstashstartu;
380     OP *	op_code_list;	/* list of (?{}) code blocks */
381 };
382 
383 #ifdef USE_ITHREADS
384 #define PM_GETRE(o)	(SvTYPE(PL_regex_pad[(o)->op_pmoffset]) == SVt_REGEXP \
385 		 	 ? (REGEXP*)(PL_regex_pad[(o)->op_pmoffset]) : NULL)
386 /* The assignment is just to enforce type safety (or at least get a warning).
387  */
388 /* With first class regexps not via a reference one needs to assign
389    &PL_sv_undef under ithreads. (This would probably work unthreaded, but NULL
390    is cheaper. I guess we could allow NULL, but the check above would get
391    more complex, and we'd have an AV with (SV*)NULL in it, which feels bad */
392 /* BEWARE - something that calls this macro passes (r) which has a side
393    effect.  */
394 #define PM_SETRE(o,r)	STMT_START {					\
395                             REGEXP *const _pm_setre = (r);		\
396                             assert(_pm_setre);				\
397 			    PL_regex_pad[(o)->op_pmoffset] = MUTABLE_SV(_pm_setre); \
398                         } STMT_END
399 #else
400 #define PM_GETRE(o)     ((o)->op_pmregexp)
401 #define PM_SETRE(o,r)   ((o)->op_pmregexp = (r))
402 #endif
403 
404 /* Leave some space, so future bit allocations can go either in the shared or
405  * unshared area without affecting binary compatibility */
406 #define PMf_BASE_SHIFT (_RXf_PMf_SHIFT_NEXT+6)
407 
408 /* 'use re "taint"' in scope: taint $1 etc. if target tainted */
409 #define PMf_RETAINT	(1<<(PMf_BASE_SHIFT+0))
410 
411 /* match successfully only once per reset, with related flag RXf_USED in
412  * re->extflags holding state.  This is used only for ?? matches, and only on
413  * OP_MATCH and OP_QR */
414 #define PMf_ONCE	(1<<(PMf_BASE_SHIFT+1))
415 
416 /* PMf_ONCE, i.e. ?pat?, has matched successfully.  Not used under threading. */
417 #define PMf_USED        (1<<(PMf_BASE_SHIFT+3))
418 
419 /* subst replacement is constant */
420 #define PMf_CONST	(1<<(PMf_BASE_SHIFT+4))
421 
422 /* keep 1st runtime pattern forever */
423 #define PMf_KEEP	(1<<(PMf_BASE_SHIFT+5))
424 
425 #define PMf_GLOBAL	(1<<(PMf_BASE_SHIFT+6))	/* pattern had a g modifier */
426 
427 /* don't reset pos() if //g fails */
428 #define PMf_CONTINUE	(1<<(PMf_BASE_SHIFT+7))
429 
430 /* evaluating replacement as expr */
431 #define PMf_EVAL	(1<<(PMf_BASE_SHIFT+8))
432 
433 /* Return substituted string instead of modifying it. */
434 #define PMf_NONDESTRUCT	(1<<(PMf_BASE_SHIFT+9))
435 
436 /* the pattern has a CV attached (currently only under qr/...(?{}).../) */
437 #define PMf_HAS_CV	(1<<(PMf_BASE_SHIFT+10))
438 
439 /* op_code_list is private; don't free it etc. It may well point to
440  * code within another sub, with different pad etc */
441 #define PMf_CODELIST_PRIVATE	(1<<(PMf_BASE_SHIFT+11))
442 
443 /* the PMOP is a QR (we should be able to detect that from the op type,
444  * but the regex compilation API passes just the pm flags, not the op
445  * itself */
446 #define PMf_IS_QR	(1<<(PMf_BASE_SHIFT+12))
447 #define PMf_USE_RE_EVAL	(1<<(PMf_BASE_SHIFT+13)) /* use re'eval' in scope */
448 
449 #if PMf_BASE_SHIFT+13 > 31
450 #   error Too many PMf_ bits used.  See above and regnodes.h for any spare in middle
451 #endif
452 
453 #ifdef USE_ITHREADS
454 
455 #  define PmopSTASH(o)         ((o)->op_pmflags & PMf_ONCE                         \
456                                 ? PL_stashpad[(o)->op_pmstashstartu.op_pmstashoff]   \
457                                 : NULL)
458 #  define PmopSTASH_set(o,hv)	\
459 	(assert_((o)->op_pmflags & PMf_ONCE)				\
460 	 (o)->op_pmstashstartu.op_pmstashoff =				\
461 	    (hv) ? alloccopstash(hv) : 0)
462 #else
463 #  define PmopSTASH(o)							\
464     (((o)->op_pmflags & PMf_ONCE) ? (o)->op_pmstashstartu.op_pmstash : NULL)
465 #  if defined (DEBUGGING) && defined(__GNUC__) && !defined(PERL_GCC_BRACE_GROUPS_FORBIDDEN)
466 #    define PmopSTASH_set(o,hv)		({				\
467 	assert((o)->op_pmflags & PMf_ONCE);				\
468 	((o)->op_pmstashstartu.op_pmstash = (hv));			\
469     })
470 #  else
471 #    define PmopSTASH_set(o,hv)	((o)->op_pmstashstartu.op_pmstash = (hv))
472 #  endif
473 #endif
474 #define PmopSTASHPV(o)	(PmopSTASH(o) ? HvNAME_get(PmopSTASH(o)) : NULL)
475    /* op_pmstashstartu.op_pmstash is not refcounted */
476 #define PmopSTASHPV_set(o,pv)	PmopSTASH_set((o), gv_stashpv(pv,GV_ADD))
477 
478 struct svop {
479     BASEOP
480     SV *	op_sv;
481 };
482 
483 struct padop {
484     BASEOP
485     PADOFFSET	op_padix;
486 };
487 
488 struct pvop {
489     BASEOP
490     char *	op_pv;
491 };
492 
493 struct loop {
494     BASEOP
495     OP *	op_first;
496     OP *	op_last;
497     OP *	op_redoop;
498     OP *	op_nextop;
499     OP *	op_lastop;
500 };
501 
502 #define cUNOPx(o)	((UNOP*)o)
503 #define cBINOPx(o)	((BINOP*)o)
504 #define cLISTOPx(o)	((LISTOP*)o)
505 #define cLOGOPx(o)	((LOGOP*)o)
506 #define cPMOPx(o)	((PMOP*)o)
507 #define cSVOPx(o)	((SVOP*)o)
508 #define cPADOPx(o)	((PADOP*)o)
509 #define cPVOPx(o)	((PVOP*)o)
510 #define cCOPx(o)	((COP*)o)
511 #define cLOOPx(o)	((LOOP*)o)
512 
513 #define cUNOP		cUNOPx(PL_op)
514 #define cBINOP		cBINOPx(PL_op)
515 #define cLISTOP		cLISTOPx(PL_op)
516 #define cLOGOP		cLOGOPx(PL_op)
517 #define cPMOP		cPMOPx(PL_op)
518 #define cSVOP		cSVOPx(PL_op)
519 #define cPADOP		cPADOPx(PL_op)
520 #define cPVOP		cPVOPx(PL_op)
521 #define cCOP		cCOPx(PL_op)
522 #define cLOOP		cLOOPx(PL_op)
523 
524 #define cUNOPo		cUNOPx(o)
525 #define cBINOPo		cBINOPx(o)
526 #define cLISTOPo	cLISTOPx(o)
527 #define cLOGOPo		cLOGOPx(o)
528 #define cPMOPo		cPMOPx(o)
529 #define cSVOPo		cSVOPx(o)
530 #define cPADOPo		cPADOPx(o)
531 #define cPVOPo		cPVOPx(o)
532 #define cCOPo		cCOPx(o)
533 #define cLOOPo		cLOOPx(o)
534 
535 #define kUNOP		cUNOPx(kid)
536 #define kBINOP		cBINOPx(kid)
537 #define kLISTOP		cLISTOPx(kid)
538 #define kLOGOP		cLOGOPx(kid)
539 #define kPMOP		cPMOPx(kid)
540 #define kSVOP		cSVOPx(kid)
541 #define kPADOP		cPADOPx(kid)
542 #define kPVOP		cPVOPx(kid)
543 #define kCOP		cCOPx(kid)
544 #define kLOOP		cLOOPx(kid)
545 
546 
547 #ifdef USE_ITHREADS
548 #  define	cGVOPx_gv(o)	((GV*)PAD_SVl(cPADOPx(o)->op_padix))
549 #  define	IS_PADGV(v)	(v && SvTYPE(v) == SVt_PVGV && isGV_with_GP(v) \
550 				 && GvIN_PAD(v))
551 #  define	IS_PADCONST(v) \
552 	(v && (SvREADONLY(v) || (SvIsCOW(v) && !SvLEN(v))))
553 #  define	cSVOPx_sv(v)	(cSVOPx(v)->op_sv \
554 				 ? cSVOPx(v)->op_sv : PAD_SVl((v)->op_targ))
555 #  define	cSVOPx_svp(v)	(cSVOPx(v)->op_sv \
556 				 ? &cSVOPx(v)->op_sv : &PAD_SVl((v)->op_targ))
557 #else
558 #  define	cGVOPx_gv(o)	((GV*)cSVOPx(o)->op_sv)
559 #  define	IS_PADGV(v)	FALSE
560 #  define	IS_PADCONST(v)	FALSE
561 #  define	cSVOPx_sv(v)	(cSVOPx(v)->op_sv)
562 #  define	cSVOPx_svp(v)	(&cSVOPx(v)->op_sv)
563 #endif
564 
565 #define	cGVOP_gv		cGVOPx_gv(PL_op)
566 #define	cGVOPo_gv		cGVOPx_gv(o)
567 #define	kGVOP_gv		cGVOPx_gv(kid)
568 #define cSVOP_sv		cSVOPx_sv(PL_op)
569 #define cSVOPo_sv		cSVOPx_sv(o)
570 #define kSVOP_sv		cSVOPx_sv(kid)
571 
572 #ifndef PERL_CORE
573 #  define Nullop ((OP*)NULL)
574 #endif
575 
576 /* Lowest byte of PL_opargs */
577 #define OA_MARK 1
578 #define OA_FOLDCONST 2
579 #define OA_RETSCALAR 4
580 #define OA_TARGET 8
581 #define OA_TARGLEX 16
582 #define OA_OTHERINT 32
583 #define OA_DANGEROUS 64
584 #define OA_DEFGV 128
585 
586 /* The next 4 bits encode op class information */
587 #define OCSHIFT 8
588 
589 #define OA_CLASS_MASK (15 << OCSHIFT)
590 
591 #define OA_BASEOP (0 << OCSHIFT)
592 #define OA_UNOP (1 << OCSHIFT)
593 #define OA_BINOP (2 << OCSHIFT)
594 #define OA_LOGOP (3 << OCSHIFT)
595 #define OA_LISTOP (4 << OCSHIFT)
596 #define OA_PMOP (5 << OCSHIFT)
597 #define OA_SVOP (6 << OCSHIFT)
598 #define OA_PADOP (7 << OCSHIFT)
599 #define OA_PVOP_OR_SVOP (8 << OCSHIFT)
600 #define OA_LOOP (9 << OCSHIFT)
601 #define OA_COP (10 << OCSHIFT)
602 #define OA_BASEOP_OR_UNOP (11 << OCSHIFT)
603 #define OA_FILESTATOP (12 << OCSHIFT)
604 #define OA_LOOPEXOP (13 << OCSHIFT)
605 
606 #define OASHIFT 12
607 
608 /* Remaining nybbles of PL_opargs */
609 #define OA_SCALAR 1
610 #define OA_LIST 2
611 #define OA_AVREF 3
612 #define OA_HVREF 4
613 #define OA_CVREF 5
614 #define OA_FILEREF 6
615 #define OA_SCALARREF 7
616 #define OA_OPTIONAL 8
617 
618 /* Op_REFCNT is a reference count at the head of each op tree: needed
619  * since the tree is shared between threads, and between cloned closure
620  * copies in the same thread. OP_REFCNT_LOCK/UNLOCK is used when modifying
621  * this count.
622  * The same mutex is used to protect the refcounts of the reg_trie_data
623  * and reg_ac_data structures, which are shared between duplicated
624  * regexes.
625  */
626 
627 #ifdef USE_ITHREADS
628 #  define OP_REFCNT_INIT		MUTEX_INIT(&PL_op_mutex)
629 #  ifdef PERL_CORE
630 #    define OP_REFCNT_LOCK		MUTEX_LOCK(&PL_op_mutex)
631 #    define OP_REFCNT_UNLOCK		MUTEX_UNLOCK(&PL_op_mutex)
632 #  else
633 #    define OP_REFCNT_LOCK		op_refcnt_lock()
634 #    define OP_REFCNT_UNLOCK		op_refcnt_unlock()
635 #  endif
636 #  define OP_REFCNT_TERM		MUTEX_DESTROY(&PL_op_mutex)
637 #else
638 #  define OP_REFCNT_INIT		NOOP
639 #  define OP_REFCNT_LOCK		NOOP
640 #  define OP_REFCNT_UNLOCK		NOOP
641 #  define OP_REFCNT_TERM		NOOP
642 #endif
643 
644 #define OpREFCNT_set(o,n)		((o)->op_targ = (n))
645 #ifdef PERL_DEBUG_READONLY_OPS
646 #  define OpREFCNT_inc(o)		Perl_op_refcnt_inc(aTHX_ o)
647 #  define OpREFCNT_dec(o)		Perl_op_refcnt_dec(aTHX_ o)
648 #else
649 #  define OpREFCNT_inc(o)		((o) ? (++(o)->op_targ, (o)) : NULL)
650 #  define OpREFCNT_dec(o)		(--(o)->op_targ)
651 #endif
652 
653 /* flags used by Perl_load_module() */
654 #define PERL_LOADMOD_DENY		0x1	/* no Module */
655 #define PERL_LOADMOD_NOIMPORT		0x2	/* use Module () */
656 #define PERL_LOADMOD_IMPORT_OPS		0x4	/* use Module (...) */
657 
658 #if defined(PERL_IN_PERLY_C) || defined(PERL_IN_OP_C)
659 #define ref(o, type) doref(o, type, TRUE)
660 #endif
661 
662 /*
663 =head1 Optree Manipulation Functions
664 
665 =for apidoc Am|OP*|LINKLIST|OP *o
666 Given the root of an optree, link the tree in execution order using the
667 C<op_next> pointers and return the first op executed. If this has
668 already been done, it will not be redone, and C<< o->op_next >> will be
669 returned. If C<< o->op_next >> is not already set, I<o> should be at
670 least an C<UNOP>.
671 
672 =cut
673 */
674 
675 #define LINKLIST(o) ((o)->op_next ? (o)->op_next : op_linklist((OP*)o))
676 
677 /* no longer used anywhere in core */
678 #ifndef PERL_CORE
679 #define cv_ckproto(cv, gv, p) \
680    cv_ckproto_len_flags((cv), (gv), (p), (p) ? strlen(p) : 0, 0)
681 #endif
682 
683 #ifdef PERL_CORE
684 #  define my(o)	my_attrs((o), NULL)
685 #endif
686 
687 #ifdef USE_REENTRANT_API
688 #include "reentr.h"
689 #endif
690 
691 #define NewOp(m,var,c,type)	\
692 	(var = (type *) Perl_Slab_Alloc(aTHX_ c*sizeof(type)))
693 #define NewOpSz(m,var,size)	\
694 	(var = (OP *) Perl_Slab_Alloc(aTHX_ size))
695 #define FreeOp(p) Perl_Slab_Free(aTHX_ p)
696 
697 /*
698  * The per-CV op slabs consist of a header (the opslab struct) and a bunch
699  * of space for allocating op slots, each of which consists of two pointers
700  * followed by an op.  The first pointer points to the next op slot.  The
701  * second points to the slab.  At the end of the slab is a null pointer,
702  * so that slot->opslot_next - slot can be used to determine the size
703  * of the op.
704  *
705  * Each CV can have multiple slabs; opslab_next points to the next slab, to
706  * form a chain.  All bookkeeping is done on the first slab, which is where
707  * all the op slots point.
708  *
709  * Freed ops are marked as freed and attached to the freed chain
710  * via op_next pointers.
711  *
712  * When there is more than one slab, the second slab in the slab chain is
713  * assumed to be the one with free space available.  It is used when allo-
714  * cating an op if there are no freed ops available or big enough.
715  */
716 
717 #ifdef PERL_CORE
718 struct opslot {
719     /* keep opslot_next first */
720     OPSLOT *	opslot_next;		/* next slot */
721     OPSLAB *	opslot_slab;		/* owner */
722     OP		opslot_op;		/* the op itself */
723 };
724 
725 struct opslab {
726     OPSLOT *	opslab_first;		/* first op in this slab */
727     OPSLAB *	opslab_next;		/* next slab */
728     OP *	opslab_freed;		/* chain of freed ops */
729     size_t	opslab_refcnt;		/* number of ops */
730 # ifdef PERL_DEBUG_READONLY_OPS
731     U16		opslab_size;		/* size of slab in pointers */
732     bool	opslab_readonly;
733 # endif
734     OPSLOT	opslab_slots;		/* slots begin here */
735 };
736 
737 # define OPSLOT_HEADER		STRUCT_OFFSET(OPSLOT, opslot_op)
738 # define OPSLOT_HEADER_P	(OPSLOT_HEADER/sizeof(I32 *))
739 # define OpSLOT(o)		(assert_(o->op_slabbed) \
740 				 (OPSLOT *)(((char *)o)-OPSLOT_HEADER))
741 # define OpSLAB(o)		OpSLOT(o)->opslot_slab
742 # define OpslabREFCNT_dec(slab)      \
743 	(((slab)->opslab_refcnt == 1) \
744 	 ? opslab_free_nopad(slab)     \
745 	 : (void)--(slab)->opslab_refcnt)
746   /* Variant that does not null out the pads */
747 # define OpslabREFCNT_dec_padok(slab) \
748 	(((slab)->opslab_refcnt == 1)  \
749 	 ? opslab_free(slab)		\
750 	 : (void)--(slab)->opslab_refcnt)
751 #endif
752 
753 struct block_hooks {
754     U32	    bhk_flags;
755     void    (*bhk_start)	(pTHX_ int full);
756     void    (*bhk_pre_end)	(pTHX_ OP **seq);
757     void    (*bhk_post_end)	(pTHX_ OP **seq);
758     void    (*bhk_eval)		(pTHX_ OP *const saveop);
759 };
760 
761 /*
762 =head1 Compile-time scope hooks
763 
764 =for apidoc mx|U32|BhkFLAGS|BHK *hk
765 Return the BHK's flags.
766 
767 =for apidoc mx|void *|BhkENTRY|BHK *hk|which
768 Return an entry from the BHK structure. I<which> is a preprocessor token
769 indicating which entry to return. If the appropriate flag is not set
770 this will return NULL. The type of the return value depends on which
771 entry you ask for.
772 
773 =for apidoc Amx|void|BhkENTRY_set|BHK *hk|which|void *ptr
774 Set an entry in the BHK structure, and set the flags to indicate it is
775 valid. I<which> is a preprocessing token indicating which entry to set.
776 The type of I<ptr> depends on the entry.
777 
778 =for apidoc Amx|void|BhkDISABLE|BHK *hk|which
779 Temporarily disable an entry in this BHK structure, by clearing the
780 appropriate flag. I<which> is a preprocessor token indicating which
781 entry to disable.
782 
783 =for apidoc Amx|void|BhkENABLE|BHK *hk|which
784 Re-enable an entry in this BHK structure, by setting the appropriate
785 flag. I<which> is a preprocessor token indicating which entry to enable.
786 This will assert (under -DDEBUGGING) if the entry doesn't contain a valid
787 pointer.
788 
789 =for apidoc mx|void|CALL_BLOCK_HOOKS|which|arg
790 Call all the registered block hooks for type I<which>. I<which> is a
791 preprocessing token; the type of I<arg> depends on I<which>.
792 
793 =cut
794 */
795 
796 #define BhkFLAGS(hk)		((hk)->bhk_flags)
797 
798 #define BHKf_bhk_start	    0x01
799 #define BHKf_bhk_pre_end    0x02
800 #define BHKf_bhk_post_end   0x04
801 #define BHKf_bhk_eval	    0x08
802 
803 #define BhkENTRY(hk, which) \
804     ((BhkFLAGS(hk) & BHKf_ ## which) ? ((hk)->which) : NULL)
805 
806 #define BhkENABLE(hk, which) \
807     STMT_START { \
808 	BhkFLAGS(hk) |= BHKf_ ## which; \
809 	assert(BhkENTRY(hk, which)); \
810     } STMT_END
811 
812 #define BhkDISABLE(hk, which) \
813     STMT_START { \
814 	BhkFLAGS(hk) &= ~(BHKf_ ## which); \
815     } STMT_END
816 
817 #define BhkENTRY_set(hk, which, ptr) \
818     STMT_START { \
819 	(hk)->which = ptr; \
820 	BhkENABLE(hk, which); \
821     } STMT_END
822 
823 #define CALL_BLOCK_HOOKS(which, arg) \
824     STMT_START { \
825 	if (PL_blockhooks) { \
826 	    I32 i; \
827 	    for (i = av_len(PL_blockhooks); i >= 0; i--) { \
828 		SV *sv = AvARRAY(PL_blockhooks)[i]; \
829 		BHK *hk; \
830 		\
831 		assert(SvIOK(sv)); \
832 		if (SvUOK(sv)) \
833 		    hk = INT2PTR(BHK *, SvUVX(sv)); \
834 		else \
835 		    hk = INT2PTR(BHK *, SvIVX(sv)); \
836 		\
837 		if (BhkENTRY(hk, which)) \
838 		    BhkENTRY(hk, which)(aTHX_ arg); \
839 	    } \
840 	} \
841     } STMT_END
842 
843 /* flags for rv2cv_op_cv */
844 
845 #define RV2CVOPCV_MARK_EARLY     0x00000001
846 #define RV2CVOPCV_RETURN_NAME_GV 0x00000002
847 
848 #define op_lvalue(op,t) Perl_op_lvalue_flags(aTHX_ op,t,0)
849 
850 /* flags for op_lvalue_flags */
851 
852 #define OP_LVALUE_NO_CROAK 1
853 
854 /*
855 =head1 Custom Operators
856 
857 =for apidoc Am|U32|XopFLAGS|XOP *xop
858 Return the XOP's flags.
859 
860 =for apidoc Am||XopENTRY|XOP *xop|which
861 Return a member of the XOP structure. I<which> is a cpp token indicating
862 which entry to return. If the member is not set this will return a
863 default value. The return type depends on I<which>.
864 
865 =for apidoc Am|void|XopENTRY_set|XOP *xop|which|value
866 Set a member of the XOP structure. I<which> is a cpp token indicating
867 which entry to set. See L<perlguts/"Custom Operators"> for details about
868 the available members and how they are used.
869 
870 =for apidoc Am|void|XopDISABLE|XOP *xop|which
871 Temporarily disable a member of the XOP, by clearing the appropriate flag.
872 
873 =for apidoc Am|void|XopENABLE|XOP *xop|which
874 Reenable a member of the XOP which has been disabled.
875 
876 =cut
877 */
878 
879 struct custom_op {
880     U32		    xop_flags;
881     const char	   *xop_name;
882     const char	   *xop_desc;
883     U32		    xop_class;
884     void	  (*xop_peep)(pTHX_ OP *o, OP *oldop);
885 };
886 
887 #define XopFLAGS(xop) ((xop)->xop_flags)
888 
889 #define XOPf_xop_name	0x01
890 #define XOPf_xop_desc	0x02
891 #define XOPf_xop_class	0x04
892 #define XOPf_xop_peep	0x08
893 
894 #define XOPd_xop_name	PL_op_name[OP_CUSTOM]
895 #define XOPd_xop_desc	PL_op_desc[OP_CUSTOM]
896 #define XOPd_xop_class	OA_BASEOP
897 #define XOPd_xop_peep	((Perl_cpeep_t)0)
898 
899 #define XopENTRY_set(xop, which, to) \
900     STMT_START { \
901 	(xop)->which = (to); \
902 	(xop)->xop_flags |= XOPf_ ## which; \
903     } STMT_END
904 
905 #define XopENTRY(xop, which) \
906     ((XopFLAGS(xop) & XOPf_ ## which) ? (xop)->which : XOPd_ ## which)
907 
908 #define XopDISABLE(xop, which) ((xop)->xop_flags &= ~XOPf_ ## which)
909 #define XopENABLE(xop, which) \
910     STMT_START { \
911 	(xop)->xop_flags |= XOPf_ ## which; \
912 	assert(XopENTRY(xop, which)); \
913     } STMT_END
914 
915 /*
916 =head1 Optree Manipulation Functions
917 
918 =for apidoc Am|const char *|OP_NAME|OP *o
919 Return the name of the provided OP. For core ops this looks up the name
920 from the op_type; for custom ops from the op_ppaddr.
921 
922 =for apidoc Am|const char *|OP_DESC|OP *o
923 Return a short description of the provided OP.
924 
925 =for apidoc Am|U32|OP_CLASS|OP *o
926 Return the class of the provided OP: that is, which of the *OP
927 structures it uses. For core ops this currently gets the information out
928 of PL_opargs, which does not always accurately reflect the type used.
929 For custom ops the type is returned from the registration, and it is up
930 to the registree to ensure it is accurate. The value returned will be
931 one of the OA_* constants from op.h.
932 
933 =cut
934 */
935 
936 #define OP_NAME(o) ((o)->op_type == OP_CUSTOM \
937 		    ? XopENTRY(Perl_custom_op_xop(aTHX_ o), xop_name) \
938 		    : PL_op_name[(o)->op_type])
939 #define OP_DESC(o) ((o)->op_type == OP_CUSTOM \
940 		    ? XopENTRY(Perl_custom_op_xop(aTHX_ o), xop_desc) \
941 		    : PL_op_desc[(o)->op_type])
942 #define OP_CLASS(o) ((o)->op_type == OP_CUSTOM \
943 		     ? XopENTRY(Perl_custom_op_xop(aTHX_ o), xop_class) \
944 		     : (PL_opargs[(o)->op_type] & OA_CLASS_MASK))
945 
946 #define newSUB(f, o, p, b)	Perl_newATTRSUB(aTHX_ (f), (o), (p), NULL, (b))
947 
948 #ifdef PERL_MAD
949 #  define MAD_NULL 1
950 #  define MAD_PV 2
951 #  define MAD_OP 3
952 #  define MAD_SV 4
953 
954 struct madprop {
955     MADPROP* mad_next;
956     void *mad_val;
957     U32 mad_vlen;
958 /*    short mad_count; */
959     char mad_key;
960     char mad_type;
961 };
962 
963 struct token {
964     I32 tk_type;
965     YYSTYPE tk_lval;
966     MADPROP* tk_mad;
967 };
968 #endif
969 
970 /*
971  * Values that can be held by mad_key :
972  * ^       unfilled head spot
973  * ,       literal ,
974  * ;       literal ; (blank if implicit ; at end of block)
975  * :       literal : from ?: or attr list
976  * +       unary +
977  * ?       literal ? from ?:
978  * (       literal (
979  * )       literal )
980  * [       literal [
981  * ]       literal ]
982  * {       literal {
983  * }       literal }
984  * @       literal @ sigil
985  * $       literal $ sigil
986  * *       literal * sigil
987  * !       use is source filtered
988  * &       & or sub
989  * #       whitespace/comment following ; or }
990  * #       $# sigil
991  * 1       1st ; from for(;;)
992  * 1       retired protasis
993  * 2       2nd ; from for(;;)
994  * 2       retired apodosis
995  * 3       C-style for list
996  * a       sub or var attributes
997  * a       non-method arrow operator
998  * A       method arrow operator
999  * A       use import args
1000  * b       format block
1001  * B       retired stub block
1002  * C       constant conditional op
1003  * d       declarator
1004  * D       do block
1005  * e       unreached "else" (see C)
1006  * e       expression producing E
1007  * E       tr/E/R/, /E/
1008  * f       folded constant op
1009  * F       peg op for format
1010  * g       op was forced to be a word
1011  * i       if/unless modifier
1012  * I       if/elsif/unless statement
1013  * k       local declarator
1014  * K       retired kid op
1015  * l       last index of array ($#foo)
1016  * L       label
1017  * m       modifier on regex
1018  * n       sub or format name
1019  * o       current operator/declarator name
1020  * o       else/continue
1021  * O       generic optimized op
1022  * p       peg to hold extra whitespace at statement level
1023  * P       peg op for package declaration
1024  * q       opening quote
1025  * =       quoted material
1026  * Q       closing quote
1027  * Q       optimized qw//
1028  * r       expression producing R
1029  * R       tr/E/R/ s/E/R/
1030  * s       sub signature
1031  * S       use import stub (no import)
1032  * S       retired sort block
1033  * t       unreached "then" (see C)
1034  * U       use import op
1035  * v       private sv of for loop
1036  * V       use version
1037  * w       while/until modifier
1038  * W       while/for statement
1039  * x       optimized qw
1040  * X       random thing
1041  * _       whitespace/comments preceding anything else
1042  * ~       =~ operator
1043  */
1044 
1045 /*
1046 =head1 Hook manipulation
1047 */
1048 
1049 #ifdef USE_ITHREADS
1050 #  define OP_CHECK_MUTEX_INIT		MUTEX_INIT(&PL_check_mutex)
1051 #  define OP_CHECK_MUTEX_LOCK		MUTEX_LOCK(&PL_check_mutex)
1052 #  define OP_CHECK_MUTEX_UNLOCK		MUTEX_UNLOCK(&PL_check_mutex)
1053 #  define OP_CHECK_MUTEX_TERM		MUTEX_DESTROY(&PL_check_mutex)
1054 #else
1055 #  define OP_CHECK_MUTEX_INIT		NOOP
1056 #  define OP_CHECK_MUTEX_LOCK		NOOP
1057 #  define OP_CHECK_MUTEX_UNLOCK		NOOP
1058 #  define OP_CHECK_MUTEX_TERM		NOOP
1059 #endif
1060 
1061 /*
1062  * Local variables:
1063  * c-indentation-style: bsd
1064  * c-basic-offset: 4
1065  * indent-tabs-mode: nil
1066  * End:
1067  *
1068  * ex: set ts=8 sts=4 sw=4 et:
1069  */
1070