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Add test for RT #2166: foreach spuriously autovivifies
[perl5.git] / scope.h
1 /*    scope.h
2  *
3  *    Copyright (C) 1993, 1994, 1996, 1997, 1998, 1999,
4  *    2000, 2001, 2002, 2004, 2005 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 #define SAVEt_ITEM              0
12 #define SAVEt_SV                1
13 #define SAVEt_AV                2
14 #define SAVEt_HV                3
15 #define SAVEt_INT               4
16 #define SAVEt_LONG              5
17 #define SAVEt_I32               6
18 #define SAVEt_IV                7
19 #define SAVEt_SPTR              8
20 #define SAVEt_APTR              9
21 #define SAVEt_HPTR              10
22 #define SAVEt_PPTR              11
23 #define SAVEt_NSTAB             12
24 #define SAVEt_SVREF             13
25 #define SAVEt_GP                14
26 #define SAVEt_FREESV            15
27 #define SAVEt_FREEOP            16
28 #define SAVEt_FREEPV            17
29 #define SAVEt_CLEARSV           18
30 #define SAVEt_DELETE            19
31 #define SAVEt_DESTRUCTOR        20
32 #define SAVEt_REGCONTEXT        21
33 #define SAVEt_STACK_POS         22
34 #define SAVEt_I16               23
35 #define SAVEt_AELEM             24
36 #define SAVEt_HELEM             25
37 #define SAVEt_OP                26
38 #define SAVEt_HINTS             27
39 #define SAVEt_ALLOC             28
40 #define SAVEt_GENERIC_SVREF     29
41 #define SAVEt_DESTRUCTOR_X      30
42 #define SAVEt_VPTR              31
43 #define SAVEt_I8                32
44 #define SAVEt_COMPPAD           33
45 #define SAVEt_GENERIC_PVREF     34
46 #define SAVEt_PADSV             35
47 #define SAVEt_MORTALIZESV       36
48 #define SAVEt_SHARED_PVREF      37
49 #define SAVEt_BOOL              38
50 #define SAVEt_SET_SVFLAGS       39
51 #define SAVEt_SAVESWITCHSTACK   40
52
53 #ifndef SCOPE_SAVES_SIGNAL_MASK
54 #define SCOPE_SAVES_SIGNAL_MASK 0
55 #endif
56
57 #define SSCHECK(need) if (PL_savestack_ix + (need) > PL_savestack_max) savestack_grow()
58 #define SSGROW(need) if (PL_savestack_ix + (need) > PL_savestack_max) savestack_grow_cnt(need)
59 #define SSPUSHINT(i) (PL_savestack[PL_savestack_ix++].any_i32 = (I32)(i))
60 #define SSPUSHLONG(i) (PL_savestack[PL_savestack_ix++].any_long = (long)(i))
61 #define SSPUSHBOOL(p) (PL_savestack[PL_savestack_ix++].any_bool = (p))
62 #define SSPUSHIV(i) (PL_savestack[PL_savestack_ix++].any_iv = (IV)(i))
63 #define SSPUSHPTR(p) (PL_savestack[PL_savestack_ix++].any_ptr = (void*)(p))
64 #define SSPUSHDPTR(p) (PL_savestack[PL_savestack_ix++].any_dptr = (p))
65 #define SSPUSHDXPTR(p) (PL_savestack[PL_savestack_ix++].any_dxptr = (p))
66 #define SSPOPINT (PL_savestack[--PL_savestack_ix].any_i32)
67 #define SSPOPLONG (PL_savestack[--PL_savestack_ix].any_long)
68 #define SSPOPBOOL (PL_savestack[--PL_savestack_ix].any_bool)
69 #define SSPOPIV (PL_savestack[--PL_savestack_ix].any_iv)
70 #define SSPOPPTR (PL_savestack[--PL_savestack_ix].any_ptr)
71 #define SSPOPDPTR (PL_savestack[--PL_savestack_ix].any_dptr)
72 #define SSPOPDXPTR (PL_savestack[--PL_savestack_ix].any_dxptr)
73
74 /*
75 =head1 Callback Functions
76
77 =for apidoc Ams||SAVETMPS
78 Opening bracket for temporaries on a callback.  See C<FREETMPS> and
79 L<perlcall>.
80
81 =for apidoc Ams||FREETMPS
82 Closing bracket for temporaries on a callback.  See C<SAVETMPS> and
83 L<perlcall>.
84
85 =for apidoc Ams||ENTER
86 Opening bracket on a callback.  See C<LEAVE> and L<perlcall>.
87
88 =for apidoc Ams||LEAVE
89 Closing bracket on a callback.  See C<ENTER> and L<perlcall>.
90
91 =cut
92 */
93
94 #define SAVETMPS save_int((int*)&PL_tmps_floor), PL_tmps_floor = PL_tmps_ix
95 #define FREETMPS if (PL_tmps_ix > PL_tmps_floor) free_tmps()
96
97 #ifdef DEBUGGING
98 #define ENTER                                                   \
99     STMT_START {                                                \
100         push_scope();                                           \
101         DEBUG_SCOPE("ENTER")                                    \
102     } STMT_END
103 #define LEAVE                                                   \
104     STMT_START {                                                \
105         DEBUG_SCOPE("LEAVE")                                    \
106         pop_scope();                                            \
107     } STMT_END
108 #else
109 #define ENTER push_scope()
110 #define LEAVE pop_scope()
111 #endif
112 #define LEAVE_SCOPE(old) if (PL_savestack_ix > old) leave_scope(old)
113
114 #define SAVEI8(i)       save_I8((I8*)&(i))
115 #define SAVEI16(i)      save_I16((I16*)&(i))
116 #define SAVEI32(i)      save_I32((I32*)&(i))
117 #define SAVEINT(i)      save_int((int*)&(i))
118 #define SAVEIV(i)       save_iv((IV*)&(i))
119 #define SAVELONG(l)     save_long((long*)&(l))
120 #define SAVEBOOL(b)     save_bool((bool*)&(b))
121 #define SAVESPTR(s)     save_sptr((SV**)&(s))
122 #define SAVEPPTR(s)     save_pptr((char**)&(s))
123 #define SAVEVPTR(s)     save_vptr((void*)&(s))
124 #define SAVEPADSV(s)    save_padsv(s)
125 #define SAVEFREESV(s)   save_freesv((SV*)(s))
126 #define SAVEMORTALIZESV(s)      save_mortalizesv((SV*)(s))
127 #define SAVEFREEOP(o)   save_freeop((OP*)(o))
128 #define SAVEFREEPV(p)   save_freepv((char*)(p))
129 #define SAVECLEARSV(sv) save_clearsv((SV**)&(sv))
130 #define SAVEGENERICSV(s)        save_generic_svref((SV**)&(s))
131 #define SAVEGENERICPV(s)        save_generic_pvref((char**)&(s))
132 #define SAVESHAREDPV(s)         save_shared_pvref((char**)&(s))
133 #define SAVESETSVFLAGS(sv,mask,val)     save_set_svflags(sv,mask,val)
134 #define SAVEDELETE(h,k,l) \
135           save_delete((HV*)(h), (char*)(k), (I32)(l))
136 #define SAVEDESTRUCTOR(f,p) \
137           save_destructor((DESTRUCTORFUNC_NOCONTEXT_t)(f), (void*)(p))
138
139 #define SAVEDESTRUCTOR_X(f,p) \
140           save_destructor_x((DESTRUCTORFUNC_t)(f), (void*)(p))
141
142 #define SAVESTACK_POS() \
143     STMT_START {                                \
144         SSCHECK(2);                             \
145         SSPUSHINT(PL_stack_sp - PL_stack_base); \
146         SSPUSHINT(SAVEt_STACK_POS);             \
147     } STMT_END
148
149 #define SAVEOP()        save_op()
150
151 #define SAVEHINTS() \
152     STMT_START {                                        \
153         SSCHECK(3);                                     \
154         if (PL_hints & HINT_LOCALIZE_HH) {              \
155             SSPUSHPTR(GvHV(PL_hintgv));                 \
156             GvHV(PL_hintgv) = newHVhv(GvHV(PL_hintgv)); \
157         }                                               \
158         SSPUSHINT(PL_hints);                            \
159         SSPUSHINT(SAVEt_HINTS);                         \
160     } STMT_END
161
162 #define SAVECOMPPAD() \
163     STMT_START {                                                \
164         SSCHECK(2);                                             \
165         SSPUSHPTR((SV*)PL_comppad);                             \
166         SSPUSHINT(SAVEt_COMPPAD);                               \
167     } STMT_END
168
169 #define SAVESWITCHSTACK(f,t) \
170     STMT_START {                                        \
171         SSCHECK(3);                                     \
172         SSPUSHPTR((SV*)(f));                            \
173         SSPUSHPTR((SV*)(t));                            \
174         SSPUSHINT(SAVEt_SAVESWITCHSTACK);               \
175         SWITCHSTACK((f),(t));                           \
176         PL_curstackinfo->si_stack = (t);                \
177     } STMT_END
178
179 #ifdef USE_ITHREADS
180 #  define SAVECOPSTASH(c)       SAVEPPTR(CopSTASHPV(c))
181 #  define SAVECOPSTASH_FREE(c)  SAVESHAREDPV(CopSTASHPV(c))
182 #  define SAVECOPFILE(c)        SAVEPPTR(CopFILE(c))
183 #  define SAVECOPFILE_FREE(c)   SAVESHAREDPV(CopFILE(c))
184 #else
185 #  define SAVECOPSTASH(c)       SAVESPTR(CopSTASH(c))
186 #  define SAVECOPSTASH_FREE(c)  SAVECOPSTASH(c) /* XXX not refcounted */
187 #  define SAVECOPFILE(c)        SAVESPTR(CopFILEGV(c))
188 #  define SAVECOPFILE_FREE(c)   SAVEGENERICSV(CopFILEGV(c))
189 #endif
190
191 #define SAVECOPLINE(c)          SAVEI32(CopLINE(c))
192
193 /* SSNEW() temporarily allocates a specified number of bytes of data on the
194  * savestack.  It returns an integer index into the savestack, because a
195  * pointer would get broken if the savestack is moved on reallocation.
196  * SSNEWa() works like SSNEW(), but also aligns the data to the specified
197  * number of bytes.  MEM_ALIGNBYTES is perhaps the most useful.  The
198  * alignment will be preserved therough savestack reallocation *only* if
199  * realloc returns data aligned to a size divisible by "align"!
200  *
201  * SSPTR() converts the index returned by SSNEW/SSNEWa() into a pointer.
202  */
203
204 #define SSNEW(size)             Perl_save_alloc(aTHX_ (size), 0)
205 #define SSNEWt(n,t)             SSNEW((n)*sizeof(t))
206 #define SSNEWa(size,align)      Perl_save_alloc(aTHX_ (size), \
207     (align - ((int)((caddr_t)&PL_savestack[PL_savestack_ix]) % align)) % align)
208 #define SSNEWat(n,t,align)      SSNEWa((n)*sizeof(t), align)
209
210 #define SSPTR(off,type)         ((type)  ((char*)PL_savestack + off))
211 #define SSPTRt(off,type)        ((type*) ((char*)PL_savestack + off))
212