1 /*    scope.h
2  *
3  *    Copyright (C) 1993, 1994, 1996, 1997, 1998, 1999, 2000, 2001,
4  *    2002, 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 /* *** Update arg_counts[] in scope.c if you modify these */
12 
13 /* zero args */
14 
15 #define SAVEt_ALLOC		0
16 #define SAVEt_CLEARPADRANGE	1
17 #define SAVEt_CLEARSV		2
18 #define SAVEt_REGCONTEXT	3
19 
20 /* one arg */
21 
22 #define SAVEt_TMPSFLOOR		4
23 #define SAVEt_BOOL		5
24 #define SAVEt_COMPILE_WARNINGS	6
25 #define SAVEt_COMPPAD		7
26 #define SAVEt_FREECOPHH		8
27 #define SAVEt_FREEOP		9
28 #define SAVEt_FREEPV		10
29 #define SAVEt_FREESV		11
30 #define SAVEt_I16		12
31 #define SAVEt_I32_SMALL		13
32 #define SAVEt_I8		14
33 #define SAVEt_INT_SMALL		15
34 #define SAVEt_MORTALIZESV	16
35 #define SAVEt_NSTAB		17
36 #define SAVEt_OP		18
37 #define SAVEt_PARSER		19
38 #define SAVEt_STACK_POS		20
39 #define SAVEt_READONLY_OFF	21
40 #define SAVEt_FREEPADNAME	22
41 #define SAVEt_STRLEN_SMALL      23
42 
43 /* two args */
44 
45 #define SAVEt_AV		24
46 #define SAVEt_DESTRUCTOR	25
47 #define SAVEt_DESTRUCTOR_X	26
48 #define SAVEt_GENERIC_PVREF	27
49 #define SAVEt_GENERIC_SVREF	28
50 #define SAVEt_GP		29
51 #define SAVEt_GVSV		30
52 #define SAVEt_HINTS		31
53 #define SAVEt_HPTR		32
54 #define SAVEt_HV		33
55 #define SAVEt_I32		34
56 #define SAVEt_INT		35
57 #define SAVEt_ITEM		36
58 #define SAVEt_IV		37
59 #define SAVEt_LONG		38
60 #define SAVEt_PPTR		39
61 #define SAVEt_SAVESWITCHSTACK	40
62 #define SAVEt_SHARED_PVREF	41
63 #define SAVEt_SPTR		42
64 #define SAVEt_STRLEN		43
65 #define SAVEt_SV		44
66 #define SAVEt_SVREF		45
67 #define SAVEt_VPTR		46
68 #define SAVEt_ADELETE		47
69 #define SAVEt_APTR		48
70 
71 /* three args */
72 
73 #define SAVEt_HELEM		49
74 #define SAVEt_PADSV_AND_MORTALIZE 50
75 #define SAVEt_SET_SVFLAGS	51
76 #define SAVEt_GVSLOT		52
77 #define SAVEt_AELEM		53
78 #define SAVEt_DELETE		54
79 #define SAVEt_HINTS_HH		55
80 
81 
82 #define SAVEf_SETMAGIC		1
83 #define SAVEf_KEEPOLDELEM	2
84 
85 #define SAVE_TIGHT_SHIFT	6
86 #define SAVE_MASK		0x3F
87 
88 #define save_aelem(av,idx,sptr)	save_aelem_flags(av,idx,sptr,SAVEf_SETMAGIC)
89 #define save_helem(hv,key,sptr)	save_helem_flags(hv,key,sptr,SAVEf_SETMAGIC)
90 
91 #ifndef SCOPE_SAVES_SIGNAL_MASK
92 #define SCOPE_SAVES_SIGNAL_MASK 0
93 #endif
94 
95 /* the maximum number of entries that might be pushed using the SS_ADD*
96  * macros */
97 #define SS_MAXPUSH 4
98 
99 #define SSCHECK(need) if (UNLIKELY(PL_savestack_ix + (I32)(need) > PL_savestack_max)) savestack_grow()
100 #define SSGROW(need) if (UNLIKELY(PL_savestack_ix + (I32)(need) > PL_savestack_max)) savestack_grow_cnt(need)
101 #define SSPUSHINT(i) (PL_savestack[PL_savestack_ix++].any_i32 = (I32)(i))
102 #define SSPUSHLONG(i) (PL_savestack[PL_savestack_ix++].any_long = (long)(i))
103 #define SSPUSHBOOL(p) (PL_savestack[PL_savestack_ix++].any_bool = (p))
104 #define SSPUSHIV(i) (PL_savestack[PL_savestack_ix++].any_iv = (IV)(i))
105 #define SSPUSHUV(u) (PL_savestack[PL_savestack_ix++].any_uv = (UV)(u))
106 #define SSPUSHPTR(p) (PL_savestack[PL_savestack_ix++].any_ptr = (void*)(p))
107 #define SSPUSHDPTR(p) (PL_savestack[PL_savestack_ix++].any_dptr = (p))
108 #define SSPUSHDXPTR(p) (PL_savestack[PL_savestack_ix++].any_dxptr = (p))
109 
110 /* SS_ADD*: newer, faster versions of the above. Don't mix the two sets of
111  * macros. These are fast because they save reduce accesses to the PL_
112  * vars and move the size check to the end. Doing the check last means
113  * that values in registers will have been pushed and no longer needed, so
114  * don't need saving around the call to grow. Also, tail-call elimination
115  * of the grow() can be done. These changes reduce the code of something
116  * like save_pushptrptr() to half its former size.
117  * Of course, doing the size check *after* pushing means we must always
118  * ensure there are SS_MAXPUSH free slots on the savestack. This ensured
119  * bt savestack_grow() and savestack_grow_cnt always allocating SS_MAXPUSH
120  * slots more than asked for, or that it sets PL_savestack_max to
121  *
122  * These are for internal core use only and are subject to change */
123 
124 #define dSS_ADD \
125     I32 ix = PL_savestack_ix;     \
126     ANY *ssp = &PL_savestack[ix]
127 
128 #define SS_ADD_END(need) \
129     assert((need) <= SS_MAXPUSH);                               \
130     ix += (need);                                               \
131     PL_savestack_ix = ix;                                       \
132     assert(ix <= PL_savestack_max + SS_MAXPUSH);                \
133     if (UNLIKELY(ix > PL_savestack_max)) savestack_grow();      \
134     assert(PL_savestack_ix <= PL_savestack_max);
135 
136 #define SS_ADD_INT(i)   ((ssp++)->any_i32 = (I32)(i))
137 #define SS_ADD_LONG(i)  ((ssp++)->any_long = (long)(i))
138 #define SS_ADD_BOOL(p)  ((ssp++)->any_bool = (p))
139 #define SS_ADD_IV(i)    ((ssp++)->any_iv = (IV)(i))
140 #define SS_ADD_UV(u)    ((ssp++)->any_uv = (UV)(u))
141 #define SS_ADD_PTR(p)   ((ssp++)->any_ptr = (void*)(p))
142 #define SS_ADD_DPTR(p)  ((ssp++)->any_dptr = (p))
143 #define SS_ADD_DXPTR(p) ((ssp++)->any_dxptr = (p))
144 
145 #define SSPOPINT (PL_savestack[--PL_savestack_ix].any_i32)
146 #define SSPOPLONG (PL_savestack[--PL_savestack_ix].any_long)
147 #define SSPOPBOOL (PL_savestack[--PL_savestack_ix].any_bool)
148 #define SSPOPIV (PL_savestack[--PL_savestack_ix].any_iv)
149 #define SSPOPUV (PL_savestack[--PL_savestack_ix].any_uv)
150 #define SSPOPPTR (PL_savestack[--PL_savestack_ix].any_ptr)
151 #define SSPOPDPTR (PL_savestack[--PL_savestack_ix].any_dptr)
152 #define SSPOPDXPTR (PL_savestack[--PL_savestack_ix].any_dxptr)
153 
154 
155 /*
156 =for apidoc_section $callback
157 
158 =for apidoc Amns||SAVETMPS
159 Opening bracket for temporaries on a callback.  See C<L</FREETMPS>> and
160 L<perlcall>.
161 
162 =for apidoc Amns||FREETMPS
163 Closing bracket for temporaries on a callback.  See C<L</SAVETMPS>> and
164 L<perlcall>.
165 
166 =for apidoc Amns||ENTER
167 Opening bracket on a callback.  See C<L</LEAVE>> and L<perlcall>.
168 
169 =for apidoc Amns||LEAVE
170 Closing bracket on a callback.  See C<L</ENTER>> and L<perlcall>.
171 
172 =for apidoc Ams||ENTER_with_name|"name"
173 
174 Same as C<L</ENTER>>, but when debugging is enabled it also associates the
175 given literal string with the new scope.
176 
177 =for apidoc Ams||LEAVE_with_name|"name"
178 
179 Same as C<L</LEAVE>>, but when debugging is enabled it first checks that the
180 scope has the given name. C<name> must be a literal string.
181 
182 =cut
183 */
184 
185 #define SAVETMPS Perl_savetmps(aTHX)
186 
187 #define FREETMPS if (PL_tmps_ix > PL_tmps_floor) free_tmps()
188 
189 #ifdef DEBUGGING
190 #define ENTER							\
191     STMT_START {						\
192         push_scope();						\
193         DEBUG_SCOPE("ENTER")					\
194     } STMT_END
195 #define LEAVE							\
196     STMT_START {						\
197         DEBUG_SCOPE("LEAVE")					\
198         pop_scope();						\
199     } STMT_END
200 #define ENTER_with_name(name)						\
201     STMT_START {							\
202         push_scope();							\
203         if (PL_scopestack_name)						\
204             PL_scopestack_name[PL_scopestack_ix-1] = name;		\
205         DEBUG_SCOPE("ENTER \"" name "\"")				\
206     } STMT_END
207 #define LEAVE_with_name(name)						\
208     STMT_START {							\
209         DEBUG_SCOPE("LEAVE \"" name "\"")				\
210         if (PL_scopestack_name)	{					\
211             assert(((char*)PL_scopestack_name[PL_scopestack_ix-1]	\
212                         == (char*)name)					\
213                     || strEQ(PL_scopestack_name[PL_scopestack_ix-1], name));        \
214         }								\
215         pop_scope();							\
216     } STMT_END
217 #else
218 #define ENTER push_scope()
219 #define LEAVE pop_scope()
220 #define ENTER_with_name(name) ENTER
221 #define LEAVE_with_name(name) LEAVE
222 #endif
223 #define LEAVE_SCOPE(old) STMT_START { \
224         if (PL_savestack_ix > old) leave_scope(old); \
225     } STMT_END
226 
227 #define SAVEI8(i)	save_I8((I8*)&(i))
228 #define SAVEI16(i)	save_I16((I16*)&(i))
229 #define SAVEI32(i)	save_I32((I32*)&(i))
230 #define SAVEINT(i)	save_int((int*)&(i))
231 #define SAVEIV(i)	save_iv((IV*)&(i))
232 #define SAVELONG(l)	save_long((long*)&(l))
233 #define SAVEBOOL(b)	save_bool(&(b))
234 #define SAVESPTR(s)	save_sptr((SV**)&(s))
235 #define SAVEPPTR(s)	save_pptr((char**)&(s))
236 #define SAVEVPTR(s)	save_vptr((void*)&(s))
237 #define SAVEPADSVANDMORTALIZE(s)	save_padsv_and_mortalize(s)
238 #define SAVEFREESV(s)	save_freesv(MUTABLE_SV(s))
239 #define SAVEFREEPADNAME(s) save_pushptr((void *)(s), SAVEt_FREEPADNAME)
240 #define SAVEMORTALIZESV(s)	save_mortalizesv(MUTABLE_SV(s))
241 #define SAVEFREEOP(o)	save_freeop((OP*)(o))
242 #define SAVEFREEPV(p)	save_freepv((char*)(p))
243 #define SAVECLEARSV(sv)	save_clearsv((SV**)&(sv))
244 #define SAVEGENERICSV(s)	save_generic_svref((SV**)&(s))
245 #define SAVEGENERICPV(s)	save_generic_pvref((char**)&(s))
246 #define SAVESHAREDPV(s)		save_shared_pvref((char**)&(s))
247 #define SAVESETSVFLAGS(sv,mask,val)	save_set_svflags(sv,mask,val)
248 #define SAVEFREECOPHH(h)	save_pushptr((void *)(h), SAVEt_FREECOPHH)
249 #define SAVEDELETE(h,k,l) \
250           save_delete(MUTABLE_HV(h), (char*)(k), (I32)(l))
251 #define SAVEHDELETE(h,s) \
252           save_hdelete(MUTABLE_HV(h), (s))
253 #define SAVEADELETE(a,k) \
254           save_adelete(MUTABLE_AV(a), (SSize_t)(k))
255 #define SAVEDESTRUCTOR(f,p) \
256           save_destructor((DESTRUCTORFUNC_NOCONTEXT_t)(f), (void*)(p))
257 
258 #define SAVEDESTRUCTOR_X(f,p) \
259           save_destructor_x((DESTRUCTORFUNC_t)(f), (void*)(p))
260 
261 #define SAVESTACK_POS() \
262     STMT_START {				   \
263         dSS_ADD;                                   \
264         SS_ADD_INT(PL_stack_sp - PL_stack_base);   \
265         SS_ADD_UV(SAVEt_STACK_POS);                \
266         SS_ADD_END(2);                             \
267     } STMT_END
268 
269 #define SAVEOP()	save_op()
270 
271 #define SAVEHINTS()	save_hints()
272 
273 #define SAVECOMPPAD() save_pushptr(MUTABLE_SV(PL_comppad), SAVEt_COMPPAD)
274 
275 #define SAVESWITCHSTACK(f,t) \
276     STMT_START {					\
277         save_pushptrptr(MUTABLE_SV(f), MUTABLE_SV(t), SAVEt_SAVESWITCHSTACK); \
278         SWITCHSTACK((f),(t));				\
279         PL_curstackinfo->si_stack = (t);		\
280     } STMT_END
281 
282 /* Need to do the cop warnings like this, rather than a "SAVEFREESHAREDPV",
283    because realloc() means that the value can actually change. Possibly
284    could have done savefreesharedpvREF, but this way actually seems cleaner,
285    as it simplifies the code that does the saves, and reduces the load on the
286    save stack.  */
287 #define SAVECOMPILEWARNINGS() save_pushptr(PL_compiling.cop_warnings, SAVEt_COMPILE_WARNINGS)
288 
289 #define SAVEPARSER(p) save_pushptr((p), SAVEt_PARSER)
290 
291 #ifdef USE_ITHREADS
292 #  define SAVECOPSTASH_FREE(c)	SAVEIV((c)->cop_stashoff)
293 #  define SAVECOPFILE(c)	SAVEPPTR(CopFILE(c))
294 #  define SAVECOPFILE_FREE(c)	SAVESHAREDPV(CopFILE(c))
295 #else
296 #  /* XXX not refcounted */
297 #  define SAVECOPSTASH_FREE(c)	SAVESPTR(CopSTASH(c))
298 #  define SAVECOPFILE(c)	SAVESPTR(CopFILEGV(c))
299 #  define SAVECOPFILE_FREE(c)	SAVEGENERICSV(CopFILEGV(c))
300 #endif
301 
302 #define SAVECOPLINE(c)		SAVEI32(CopLINE(c))
303 
304 /* SSNEW() temporarily allocates a specified number of bytes of data on the
305  * savestack.  It returns an I32 index into the savestack, because a
306  * pointer would get broken if the savestack is moved on reallocation.
307  * SSNEWa() works like SSNEW(), but also aligns the data to the specified
308  * number of bytes.  MEM_ALIGNBYTES is perhaps the most useful.  The
309  * alignment will be preserved through savestack reallocation *only* if
310  * realloc returns data aligned to a size divisible by "align"!
311  *
312  * SSPTR() converts the index returned by SSNEW/SSNEWa() into a pointer.
313  */
314 
315 #define SSNEW(size)             Perl_save_alloc(aTHX_ (size), 0)
316 #define SSNEWt(n,t)             SSNEW((n)*sizeof(t))
317 #define SSNEWa(size,align)	Perl_save_alloc(aTHX_ (size), \
318     (I32)(align - ((size_t)((caddr_t)&PL_savestack[PL_savestack_ix]) % align)) % align)
319 #define SSNEWat(n,t,align)	SSNEWa((n)*sizeof(t), align)
320 
321 #define SSPTR(off,type)         ((type)  ((char*)PL_savestack + off))
322 #define SSPTRt(off,type)        ((type*) ((char*)PL_savestack + off))
323 
324 #define save_freesv(op)		save_pushptr((void *)(op), SAVEt_FREESV)
325 #define save_mortalizesv(op)	save_pushptr((void *)(op), SAVEt_MORTALIZESV)
326 
327 # define save_freeop(op)                    \
328 STMT_START {                                 \
329       OP * const _o = (OP *)(op);             \
330       assert(!_o->op_savefree);               \
331       _o->op_savefree = 1;                     \
332       save_pushptr((void *)(_o), SAVEt_FREEOP); \
333     } STMT_END
334 #define save_freepv(pv)		save_pushptr((void *)(pv), SAVEt_FREEPV)
335 #define save_op()		save_pushptr((void *)(PL_op), SAVEt_OP)
336 
337 /*
338  * ex: set ts=8 sts=4 sw=4 et:
339  */
340