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[perl5.git] / cop.h
1 /*    cop.h
2  *
3  *    Copyright (c) 1991-2000, Larry Wall
4  *
5  *    You may distribute under the terms of either the GNU General Public
6  *    License or the Artistic License, as specified in the README file.
7  *
8  */
9
10 struct cop {
11     BASEOP
12     char *      cop_label;      /* label for this construct */
13 #ifdef USE_ITHREADS
14     char *      cop_stashpv;    /* package line was compiled in */
15     char *      cop_file;       /* file name the following line # is from */
16 #else
17     HV *        cop_stash;      /* package line was compiled in */
18     GV *        cop_filegv;     /* file the following line # is from */
19 #endif
20     U32         cop_seq;        /* parse sequence number */
21     I32         cop_arybase;    /* array base this line was compiled with */
22     line_t      cop_line;       /* line # of this command */
23     SV *        cop_warnings;   /* lexical warnings bitmask */
24 };
25
26 #define Nullcop Null(COP*)
27
28 #ifdef USE_ITHREADS
29 #  define CopFILE(c)            ((c)->cop_file)
30 #  define CopFILEGV(c)          (CopFILE(c) \
31                                  ? gv_fetchfile(CopFILE(c)) : Nullgv)
32 #  define CopFILE_set(c,pv)     ((c)->cop_file = savepv(pv))
33 #  define CopFILESV(c)          (CopFILE(c) \
34                                  ? GvSV(gv_fetchfile(CopFILE(c))) : Nullsv)
35 #  define CopFILEAV(c)          (CopFILE(c) \
36                                  ? GvAV(gv_fetchfile(CopFILE(c))) : Nullav)
37 #  define CopSTASHPV(c)         ((c)->cop_stashpv)
38 #  define CopSTASHPV_set(c,pv)  ((c)->cop_stashpv = savepv(pv))
39 #  define CopSTASH(c)           (CopSTASHPV(c) \
40                                  ? gv_stashpv(CopSTASHPV(c),GV_ADD) : Nullhv)
41 #  define CopSTASH_set(c,hv)    CopSTASHPV_set(c, HvNAME(hv))
42 #  define CopSTASH_eq(c,hv)     ((hv)                                   \
43                                  && (CopSTASHPV(c) == HvNAME(hv)        \
44                                      || (CopSTASHPV(c) && HvNAME(hv)    \
45                                          && strEQ(CopSTASHPV(c), HvNAME(hv)))))
46 #else
47 #  define CopFILEGV(c)          ((c)->cop_filegv)
48 #  define CopFILEGV_set(c,gv)   ((c)->cop_filegv = (GV*)SvREFCNT_inc(gv))
49 #  define CopFILE_set(c,pv)     CopFILEGV_set((c), gv_fetchfile(pv))
50 #  define CopFILESV(c)          (CopFILEGV(c) ? GvSV(CopFILEGV(c)) : Nullsv)
51 #  define CopFILEAV(c)          (CopFILEGV(c) ? GvAV(CopFILEGV(c)) : Nullav)
52 #  define CopFILE(c)            (CopFILESV(c) ? SvPVX(CopFILESV(c)) : Nullch)
53 #  define CopSTASH(c)           ((c)->cop_stash)
54 #  define CopSTASH_set(c,hv)    ((c)->cop_stash = (hv))
55 #  define CopSTASHPV(c)         (CopSTASH(c) ? HvNAME(CopSTASH(c)) : Nullch)
56    /* cop_stash is not refcounted */
57 #  define CopSTASHPV_set(c,pv)  CopSTASH_set((c), gv_stashpv(pv,GV_ADD))
58 #  define CopSTASH_eq(c,hv)     (CopSTASH(c) == (hv))
59 #endif /* USE_ITHREADS */
60
61 #define CopSTASH_ne(c,hv)       (!CopSTASH_eq(c,hv))
62 #define CopLINE(c)              ((c)->cop_line)
63 #define CopLINE_inc(c)          (++CopLINE(c))
64 #define CopLINE_dec(c)          (--CopLINE(c))
65 #define CopLINE_set(c,l)        (CopLINE(c) = (l))
66
67 /*
68  * Here we have some enormously heavy (or at least ponderous) wizardry.
69  */
70
71 /* subroutine context */
72 struct block_sub {
73     CV *        cv;
74     GV *        gv;
75     GV *        dfoutgv;
76 #ifndef USE_THREADS
77     AV *        savearray;
78 #endif /* USE_THREADS */
79     AV *        argarray;
80     U16         olddepth;
81     U8          hasargs;
82     U8          lval;           /* XXX merge lval and hasargs? */
83 };
84
85 #define PUSHSUB(cx)                                                     \
86         cx->blk_sub.cv = cv;                                            \
87         cx->blk_sub.olddepth = CvDEPTH(cv);                             \
88         cx->blk_sub.hasargs = hasargs;                                  \
89         cx->blk_sub.lval = PL_op->op_private &                          \
90                               (OPpLVAL_INTRO|OPpENTERSUB_INARGS);
91
92 #define PUSHFORMAT(cx)                                                  \
93         cx->blk_sub.cv = cv;                                            \
94         cx->blk_sub.gv = gv;                                            \
95         cx->blk_sub.hasargs = 0;                                        \
96         cx->blk_sub.dfoutgv = PL_defoutgv;                              \
97         (void)SvREFCNT_inc(cx->blk_sub.dfoutgv)
98
99 #ifdef USE_THREADS
100 #  define POP_SAVEARRAY() NOOP
101 #else
102 #  define POP_SAVEARRAY()                                               \
103     STMT_START {                                                        \
104         SvREFCNT_dec(GvAV(PL_defgv));                                   \
105         GvAV(PL_defgv) = cx->blk_sub.savearray;                         \
106     } STMT_END
107 #endif /* USE_THREADS */
108
109 #ifdef USE_ITHREADS
110    /* junk in @_ spells trouble when cloning CVs, so don't leave any */
111 #  define CLEAR_ARGARRAY()      av_clear(cx->blk_sub.argarray)
112 #else
113 #  define CLEAR_ARGARRAY()      NOOP
114 #endif /* USE_ITHREADS */
115
116
117 #define POPSUB(cx,sv)                                                   \
118     STMT_START {                                                        \
119         if (cx->blk_sub.hasargs) {                                      \
120             POP_SAVEARRAY();                                            \
121             /* abandon @_ if it got reified */                          \
122             if (AvREAL(cx->blk_sub.argarray)) {                         \
123                 SSize_t fill = AvFILLp(cx->blk_sub.argarray);           \
124                 SvREFCNT_dec(cx->blk_sub.argarray);                     \
125                 cx->blk_sub.argarray = newAV();                         \
126                 av_extend(cx->blk_sub.argarray, fill);                  \
127                 AvFLAGS(cx->blk_sub.argarray) = AVf_REIFY;              \
128                 PL_curpad[0] = (SV*)cx->blk_sub.argarray;               \
129             }                                                           \
130             else {                                                      \
131                 CLEAR_ARGARRAY();                                       \
132             }                                                           \
133         }                                                               \
134         sv = (SV*)cx->blk_sub.cv;                                       \
135         if (sv && (CvDEPTH((CV*)sv) = cx->blk_sub.olddepth))            \
136             sv = Nullsv;                                                \
137     } STMT_END
138
139 #define LEAVESUB(sv)                                                    \
140     STMT_START {                                                        \
141         if (sv)                                                         \
142             SvREFCNT_dec(sv);                                           \
143     } STMT_END
144
145 #define POPFORMAT(cx)                                                   \
146         setdefout(cx->blk_sub.dfoutgv);                                 \
147         SvREFCNT_dec(cx->blk_sub.dfoutgv);
148
149 /* eval context */
150 struct block_eval {
151     I32         old_in_eval;
152     I32         old_op_type;
153     SV *        old_namesv;
154     OP *        old_eval_root;
155     SV *        cur_text;
156 };
157
158 #define PUSHEVAL(cx,n,fgv)                                              \
159     STMT_START {                                                        \
160         cx->blk_eval.old_in_eval = PL_in_eval;                          \
161         cx->blk_eval.old_op_type = PL_op->op_type;                      \
162         cx->blk_eval.old_namesv = (n ? newSVpv(n,0) : Nullsv);          \
163         cx->blk_eval.old_eval_root = PL_eval_root;                      \
164         cx->blk_eval.cur_text = PL_linestr;                             \
165     } STMT_END
166
167 #define POPEVAL(cx)                                                     \
168     STMT_START {                                                        \
169         PL_in_eval = cx->blk_eval.old_in_eval;                          \
170         optype = cx->blk_eval.old_op_type;                              \
171         PL_eval_root = cx->blk_eval.old_eval_root;                      \
172         if (cx->blk_eval.old_namesv)                                    \
173             sv_2mortal(cx->blk_eval.old_namesv);                        \
174     } STMT_END
175
176 /* loop context */
177 struct block_loop {
178     char *      label;
179     I32         resetsp;
180     OP *        redo_op;
181     OP *        next_op;
182     OP *        last_op;
183 #ifdef USE_ITHREADS
184     void *      iterdata;
185     SV **       oldcurpad;
186 #else
187     SV **       itervar;
188 #endif
189     SV *        itersave;
190     SV *        iterlval;
191     AV *        iterary;
192     IV          iterix;
193     IV          itermax;
194 };
195
196 #ifdef USE_ITHREADS
197 #  define CxITERVAR(c)                                                  \
198         ((c)->blk_loop.iterdata                                         \
199          ? (CxPADLOOP(cx)                                               \
200             ? &((c)->blk_loop.oldcurpad)[(PADOFFSET)(c)->blk_loop.iterdata]     \
201             : &GvSV((GV*)(c)->blk_loop.iterdata))                       \
202          : (SV**)NULL)
203 #  define CX_ITERDATA_SET(cx,idata)                                     \
204         cx->blk_loop.oldcurpad = PL_curpad;                             \
205         if ((cx->blk_loop.iterdata = (idata)))                          \
206             cx->blk_loop.itersave = SvREFCNT_inc(*CxITERVAR(cx));
207 #else
208 #  define CxITERVAR(c)          ((c)->blk_loop.itervar)
209 #  define CX_ITERDATA_SET(cx,ivar)                                      \
210         if ((cx->blk_loop.itervar = (SV**)(ivar)))                      \
211             cx->blk_loop.itersave = SvREFCNT_inc(*CxITERVAR(cx));
212 #endif
213
214 #define PUSHLOOP(cx, dat, s)                                            \
215         cx->blk_loop.label = PL_curcop->cop_label;                      \
216         cx->blk_loop.resetsp = s - PL_stack_base;                       \
217         cx->blk_loop.redo_op = cLOOP->op_redoop;                        \
218         cx->blk_loop.next_op = cLOOP->op_nextop;                        \
219         cx->blk_loop.last_op = cLOOP->op_lastop;                        \
220         cx->blk_loop.iterlval = Nullsv;                                 \
221         cx->blk_loop.iterary = Nullav;                                  \
222         cx->blk_loop.iterix = -1;                                       \
223         CX_ITERDATA_SET(cx,dat);
224
225 #define POPLOOP(cx)                                                     \
226         SvREFCNT_dec(cx->blk_loop.iterlval);                            \
227         if (CxITERVAR(cx)) {                                            \
228             SV **s_v_p = CxITERVAR(cx);                                 \
229             sv_2mortal(*s_v_p);                                         \
230             *s_v_p = cx->blk_loop.itersave;                             \
231         }                                                               \
232         if (cx->blk_loop.iterary && cx->blk_loop.iterary != PL_curstack)\
233             SvREFCNT_dec(cx->blk_loop.iterary);
234
235 /* context common to subroutines, evals and loops */
236 struct block {
237     I32         blku_oldsp;     /* stack pointer to copy stuff down to */
238     COP *       blku_oldcop;    /* old curcop pointer */
239     I32         blku_oldretsp;  /* return stack index */
240     I32         blku_oldmarksp; /* mark stack index */
241     I32         blku_oldscopesp;        /* scope stack index */
242     PMOP *      blku_oldpm;     /* values of pattern match vars */
243     U8          blku_gimme;     /* is this block running in list context? */
244
245     union {
246         struct block_sub        blku_sub;
247         struct block_eval       blku_eval;
248         struct block_loop       blku_loop;
249     } blk_u;
250 };
251 #define blk_oldsp       cx_u.cx_blk.blku_oldsp
252 #define blk_oldcop      cx_u.cx_blk.blku_oldcop
253 #define blk_oldretsp    cx_u.cx_blk.blku_oldretsp
254 #define blk_oldmarksp   cx_u.cx_blk.blku_oldmarksp
255 #define blk_oldscopesp  cx_u.cx_blk.blku_oldscopesp
256 #define blk_oldpm       cx_u.cx_blk.blku_oldpm
257 #define blk_gimme       cx_u.cx_blk.blku_gimme
258 #define blk_sub         cx_u.cx_blk.blk_u.blku_sub
259 #define blk_eval        cx_u.cx_blk.blk_u.blku_eval
260 #define blk_loop        cx_u.cx_blk.blk_u.blku_loop
261
262 /* Enter a block. */
263 #define PUSHBLOCK(cx,t,sp) CXINC, cx = &cxstack[cxstack_ix],            \
264         cx->cx_type             = t,                                    \
265         cx->blk_oldsp           = sp - PL_stack_base,                   \
266         cx->blk_oldcop          = PL_curcop,                            \
267         cx->blk_oldmarksp       = PL_markstack_ptr - PL_markstack,      \
268         cx->blk_oldscopesp      = PL_scopestack_ix,                     \
269         cx->blk_oldretsp        = PL_retstack_ix,                       \
270         cx->blk_oldpm           = PL_curpm,                             \
271         cx->blk_gimme           = gimme;                                \
272         DEBUG_l( PerlIO_printf(Perl_debug_log, "Entering block %ld, type %s\n", \
273                     (long)cxstack_ix, PL_block_type[CxTYPE(cx)]); )
274
275 /* Exit a block (RETURN and LAST). */
276 #define POPBLOCK(cx,pm) cx = &cxstack[cxstack_ix--],                    \
277         newsp            = PL_stack_base + cx->blk_oldsp,               \
278         PL_curcop        = cx->blk_oldcop,                              \
279         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
280         PL_scopestack_ix = cx->blk_oldscopesp,                          \
281         PL_retstack_ix   = cx->blk_oldretsp,                            \
282         pm               = cx->blk_oldpm,                               \
283         gimme            = cx->blk_gimme;                               \
284         DEBUG_l( PerlIO_printf(Perl_debug_log, "Leaving block %ld, type %s\n",          \
285                     (long)cxstack_ix+1,PL_block_type[CxTYPE(cx)]); )
286
287 /* Continue a block elsewhere (NEXT and REDO). */
288 #define TOPBLOCK(cx) cx  = &cxstack[cxstack_ix],                        \
289         PL_stack_sp      = PL_stack_base + cx->blk_oldsp,               \
290         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
291         PL_scopestack_ix = cx->blk_oldscopesp,                          \
292         PL_retstack_ix   = cx->blk_oldretsp,                            \
293         PL_curpm         = cx->blk_oldpm
294
295 /* substitution context */
296 struct subst {
297     I32         sbu_iters;
298     I32         sbu_maxiters;
299     I32         sbu_rflags;
300     I32         sbu_oldsave;
301     bool        sbu_once;
302     bool        sbu_rxtainted;
303     char *      sbu_orig;
304     SV *        sbu_dstr;
305     SV *        sbu_targ;
306     char *      sbu_s;
307     char *      sbu_m;
308     char *      sbu_strend;
309     void *      sbu_rxres;
310     REGEXP *    sbu_rx;
311 };
312 #define sb_iters        cx_u.cx_subst.sbu_iters
313 #define sb_maxiters     cx_u.cx_subst.sbu_maxiters
314 #define sb_rflags       cx_u.cx_subst.sbu_rflags
315 #define sb_oldsave      cx_u.cx_subst.sbu_oldsave
316 #define sb_once         cx_u.cx_subst.sbu_once
317 #define sb_rxtainted    cx_u.cx_subst.sbu_rxtainted
318 #define sb_orig         cx_u.cx_subst.sbu_orig
319 #define sb_dstr         cx_u.cx_subst.sbu_dstr
320 #define sb_targ         cx_u.cx_subst.sbu_targ
321 #define sb_s            cx_u.cx_subst.sbu_s
322 #define sb_m            cx_u.cx_subst.sbu_m
323 #define sb_strend       cx_u.cx_subst.sbu_strend
324 #define sb_rxres        cx_u.cx_subst.sbu_rxres
325 #define sb_rx           cx_u.cx_subst.sbu_rx
326
327 #define PUSHSUBST(cx) CXINC, cx = &cxstack[cxstack_ix],                 \
328         cx->sb_iters            = iters,                                \
329         cx->sb_maxiters         = maxiters,                             \
330         cx->sb_rflags           = r_flags,                              \
331         cx->sb_oldsave          = oldsave,                              \
332         cx->sb_once             = once,                                 \
333         cx->sb_rxtainted        = rxtainted,                            \
334         cx->sb_orig             = orig,                                 \
335         cx->sb_dstr             = dstr,                                 \
336         cx->sb_targ             = targ,                                 \
337         cx->sb_s                = s,                                    \
338         cx->sb_m                = m,                                    \
339         cx->sb_strend           = strend,                               \
340         cx->sb_rxres            = Null(void*),                          \
341         cx->sb_rx               = rx,                                   \
342         cx->cx_type             = CXt_SUBST;                            \
343         rxres_save(&cx->sb_rxres, rx)
344
345 #define POPSUBST(cx) cx = &cxstack[cxstack_ix--];                       \
346         rxres_free(&cx->sb_rxres)
347
348 struct context {
349     U32         cx_type;        /* what kind of context this is */
350     union {
351         struct block    cx_blk;
352         struct subst    cx_subst;
353     } cx_u;
354 };
355
356 #define CXTYPEMASK      0xff
357 #define CXt_NULL        0
358 #define CXt_SUB         1
359 #define CXt_EVAL        2
360 #define CXt_LOOP        3
361 #define CXt_SUBST       4
362 #define CXt_BLOCK       5
363 #define CXt_FORMAT      6
364
365 /* private flags for CXt_EVAL */
366 #define CXp_REAL        0x00000100      /* truly eval'', not a lookalike */
367 #define CXp_TRYBLOCK    0x00000200      /* eval{}, not eval'' or similar */
368
369 #ifdef USE_ITHREADS
370 /* private flags for CXt_LOOP */
371 #  define CXp_PADVAR    0x00000100      /* itervar lives on pad, iterdata
372                                            has pad offset; if not set,
373                                            iterdata holds GV* */
374 #  define CxPADLOOP(c)  (((c)->cx_type & (CXt_LOOP|CXp_PADVAR))         \
375                          == (CXt_LOOP|CXp_PADVAR))
376 #endif
377
378 #define CxTYPE(c)       ((c)->cx_type & CXTYPEMASK)
379 #define CxREALEVAL(c)   (((c)->cx_type & (CXt_EVAL|CXp_REAL))           \
380                          == (CXt_EVAL|CXp_REAL))
381 #define CxTRYBLOCK(c)   (((c)->cx_type & (CXt_EVAL|CXp_TRYBLOCK))       \
382                          == (CXt_EVAL|CXp_TRYBLOCK))
383
384 #define CXINC (cxstack_ix < cxstack_max ? ++cxstack_ix : (cxstack_ix = cxinc()))
385
386 /* "gimme" values */
387
388 /*
389 =for apidoc AmU||G_SCALAR
390 Used to indicate scalar context.  See C<GIMME_V>, C<GIMME>, and
391 L<perlcall>.
392
393 =for apidoc AmU||G_ARRAY
394 Used to indicate array context.  See C<GIMME_V>, C<GIMME> and
395 L<perlcall>.
396
397 =for apidoc AmU||G_VOID
398 Used to indicate void context.  See C<GIMME_V> and L<perlcall>.
399
400 =for apidoc AmU||G_DISCARD
401 Indicates that arguments returned from a callback should be discarded.  See
402 L<perlcall>.
403
404 =for apidoc AmU||G_EVAL
405
406 Used to force a Perl C<eval> wrapper around a callback.  See
407 L<perlcall>.
408
409 =for apidoc AmU||G_NOARGS
410
411 Indicates that no arguments are being sent to a callback.  See
412 L<perlcall>.
413
414 =cut
415 */
416
417 #define G_SCALAR        0
418 #define G_ARRAY         1
419 #define G_VOID          128     /* skip this bit when adding flags below */
420
421 /* extra flags for Perl_call_* routines */
422 #define G_DISCARD       2       /* Call FREETMPS. */
423 #define G_EVAL          4       /* Assume eval {} around subroutine call. */
424 #define G_NOARGS        8       /* Don't construct a @_ array. */
425 #define G_KEEPERR      16       /* Append errors to $@, don't overwrite it */
426 #define G_NODEBUG      32       /* Disable debugging at toplevel.  */
427 #define G_METHOD       64       /* Calling method. */
428
429 /* flag bits for PL_in_eval */
430 #define EVAL_NULL       0       /* not in an eval */
431 #define EVAL_INEVAL     1       /* some enclosing scope is an eval */
432 #define EVAL_WARNONLY   2       /* used by yywarn() when calling yyerror() */
433 #define EVAL_KEEPERR    4       /* set by Perl_call_sv if G_KEEPERR */
434
435 /* Support for switching (stack and block) contexts.
436  * This ensures magic doesn't invalidate local stack and cx pointers.
437  */
438
439 #define PERLSI_UNKNOWN          -1
440 #define PERLSI_UNDEF            0
441 #define PERLSI_MAIN             1
442 #define PERLSI_MAGIC            2
443 #define PERLSI_SORT             3
444 #define PERLSI_SIGNAL           4
445 #define PERLSI_OVERLOAD         5
446 #define PERLSI_DESTROY          6
447 #define PERLSI_WARNHOOK         7
448 #define PERLSI_DIEHOOK          8
449 #define PERLSI_REQUIRE          9
450
451 struct stackinfo {
452     AV *                si_stack;       /* stack for current runlevel */
453     PERL_CONTEXT *      si_cxstack;     /* context stack for runlevel */
454     I32                 si_cxix;        /* current context index */
455     I32                 si_cxmax;       /* maximum allocated index */
456     I32                 si_type;        /* type of runlevel */
457     struct stackinfo *  si_prev;
458     struct stackinfo *  si_next;
459     I32                 si_markoff;     /* offset where markstack begins for us.
460                                          * currently used only with DEBUGGING,
461                                          * but not #ifdef-ed for bincompat */
462 };
463
464 typedef struct stackinfo PERL_SI;
465
466 #define cxstack         (PL_curstackinfo->si_cxstack)
467 #define cxstack_ix      (PL_curstackinfo->si_cxix)
468 #define cxstack_max     (PL_curstackinfo->si_cxmax)
469
470 #ifdef DEBUGGING
471 #  define       SET_MARK_OFFSET \
472     PL_curstackinfo->si_markoff = PL_markstack_ptr - PL_markstack
473 #else
474 #  define       SET_MARK_OFFSET NOOP
475 #endif
476
477 #define PUSHSTACKi(type) \
478     STMT_START {                                                        \
479         PERL_SI *next = PL_curstackinfo->si_next;                       \
480         if (!next) {                                                    \
481             next = new_stackinfo(32, 2048/sizeof(PERL_CONTEXT) - 1);    \
482             next->si_prev = PL_curstackinfo;                            \
483             PL_curstackinfo->si_next = next;                            \
484         }                                                               \
485         next->si_type = type;                                           \
486         next->si_cxix = -1;                                             \
487         AvFILLp(next->si_stack) = 0;                                    \
488         SWITCHSTACK(PL_curstack,next->si_stack);                        \
489         PL_curstackinfo = next;                                         \
490         SET_MARK_OFFSET;                                                \
491     } STMT_END
492
493 #define PUSHSTACK PUSHSTACKi(PERLSI_UNKNOWN)
494
495 /* POPSTACK works with PL_stack_sp, so it may need to be bracketed by
496  * PUTBACK/SPAGAIN to flush/refresh any local SP that may be active */
497 #define POPSTACK \
498     STMT_START {                                                        \
499         djSP;                                                           \
500         PERL_SI *prev = PL_curstackinfo->si_prev;                       \
501         if (!prev) {                                                    \
502             PerlIO_printf(Perl_error_log, "panic: POPSTACK\n");         \
503             my_exit(1);                                                 \
504         }                                                               \
505         SWITCHSTACK(PL_curstack,prev->si_stack);                        \
506         /* don't free prev here, free them all at the END{} */          \
507         PL_curstackinfo = prev;                                         \
508     } STMT_END
509
510 #define POPSTACK_TO(s) \
511     STMT_START {                                                        \
512         while (PL_curstack != s) {                                      \
513             dounwind(-1);                                               \
514             POPSTACK;                                                   \
515         }                                                               \
516     } STMT_END