xref: /openbsd-src/gnu/usr.bin/perl/pp.h (revision d13be5d47e4149db2549a9828e244d59dbc43f15)
1 /*    pp.h
2  *
3  *    Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001,
4  *    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 #define PP(s) OP * Perl_##s(pTHX)
12 
13 /*
14 =head1 Stack Manipulation Macros
15 
16 =for apidoc AmU||SP
17 Stack pointer.  This is usually handled by C<xsubpp>.  See C<dSP> and
18 C<SPAGAIN>.
19 
20 =for apidoc AmU||MARK
21 Stack marker variable for the XSUB.  See C<dMARK>.
22 
23 =for apidoc Am|void|PUSHMARK|SP
24 Opening bracket for arguments on a callback.  See C<PUTBACK> and
25 L<perlcall>.
26 
27 =for apidoc Ams||dSP
28 Declares a local copy of perl's stack pointer for the XSUB, available via
29 the C<SP> macro.  See C<SP>.
30 
31 =for apidoc ms||djSP
32 
33 Declare Just C<SP>. This is actually identical to C<dSP>, and declares
34 a local copy of perl's stack pointer, available via the C<SP> macro.
35 See C<SP>.  (Available for backward source code compatibility with the
36 old (Perl 5.005) thread model.)
37 
38 =for apidoc Ams||dMARK
39 Declare a stack marker variable, C<mark>, for the XSUB.  See C<MARK> and
40 C<dORIGMARK>.
41 
42 =for apidoc Ams||dORIGMARK
43 Saves the original stack mark for the XSUB.  See C<ORIGMARK>.
44 
45 =for apidoc AmU||ORIGMARK
46 The original stack mark for the XSUB.  See C<dORIGMARK>.
47 
48 =for apidoc Ams||SPAGAIN
49 Refetch the stack pointer.  Used after a callback.  See L<perlcall>.
50 
51 =cut */
52 
53 #undef SP /* Solaris 2.7 i386 has this in /usr/include/sys/reg.h */
54 #define SP sp
55 #define MARK mark
56 #define TARG targ
57 
58 #define PUSHMARK(p)	\
59 	STMT_START {					\
60 	    if (++PL_markstack_ptr == PL_markstack_max)	\
61 	    markstack_grow();				\
62 	    *PL_markstack_ptr = (I32)((p) - PL_stack_base);\
63 	} STMT_END
64 
65 #define TOPMARK		(*PL_markstack_ptr)
66 #define POPMARK		(*PL_markstack_ptr--)
67 
68 #define dSP		SV **sp = PL_stack_sp
69 #define djSP		dSP
70 #define dMARK		register SV **mark = PL_stack_base + POPMARK
71 #define dORIGMARK	const I32 origmark = (I32)(mark - PL_stack_base)
72 #define ORIGMARK	(PL_stack_base + origmark)
73 
74 #define SPAGAIN		sp = PL_stack_sp
75 #define MSPAGAIN	STMT_START { sp = PL_stack_sp; mark = ORIGMARK; } STMT_END
76 
77 #define GETTARGETSTACKED targ = (PL_op->op_flags & OPf_STACKED ? POPs : PAD_SV(PL_op->op_targ))
78 #define dTARGETSTACKED SV * GETTARGETSTACKED
79 
80 #define GETTARGET targ = PAD_SV(PL_op->op_targ)
81 #define dTARGET SV * GETTARGET
82 
83 #define GETATARGET targ = (PL_op->op_flags & OPf_STACKED ? sp[-1] : PAD_SV(PL_op->op_targ))
84 #define dATARGET SV * GETATARGET
85 
86 #define dTARG SV *targ
87 
88 #define NORMAL PL_op->op_next
89 #define DIE Perl_die
90 
91 /*
92 =for apidoc Ams||PUTBACK
93 Closing bracket for XSUB arguments.  This is usually handled by C<xsubpp>.
94 See C<PUSHMARK> and L<perlcall> for other uses.
95 
96 =for apidoc Amn|SV*|POPs
97 Pops an SV off the stack.
98 
99 =for apidoc Amn|char*|POPp
100 Pops a string off the stack. Deprecated. New code should use POPpx.
101 
102 =for apidoc Amn|char*|POPpx
103 Pops a string off the stack.
104 
105 =for apidoc Amn|char*|POPpbytex
106 Pops a string off the stack which must consist of bytes i.e. characters < 256.
107 
108 =for apidoc Amn|NV|POPn
109 Pops a double off the stack.
110 
111 =for apidoc Amn|IV|POPi
112 Pops an integer off the stack.
113 
114 =for apidoc Amn|long|POPl
115 Pops a long off the stack.
116 
117 =cut
118 */
119 
120 #define PUTBACK		PL_stack_sp = sp
121 #define RETURN		return (PUTBACK, NORMAL)
122 #define RETURNOP(o)	return (PUTBACK, o)
123 #define RETURNX(x)	return (x, PUTBACK, NORMAL)
124 
125 #define POPs		(*sp--)
126 #define POPp		(SvPVx(POPs, PL_na))		/* deprecated */
127 #define POPpx		(SvPVx_nolen(POPs))
128 #define POPpconstx	(SvPVx_nolen_const(POPs))
129 #define POPpbytex	(SvPVbytex_nolen(POPs))
130 #define POPn		(SvNVx(POPs))
131 #define POPi		((IV)SvIVx(POPs))
132 #define POPu		((UV)SvUVx(POPs))
133 #define POPl		((long)SvIVx(POPs))
134 #define POPul		((unsigned long)SvIVx(POPs))
135 #ifdef HAS_QUAD
136 #define POPq		((Quad_t)SvIVx(POPs))
137 #define POPuq		((Uquad_t)SvUVx(POPs))
138 #endif
139 
140 #define TOPs		(*sp)
141 #define TOPm1s		(*(sp-1))
142 #define TOPp1s		(*(sp+1))
143 #define TOPp		(SvPV(TOPs, PL_na))		/* deprecated */
144 #define TOPpx		(SvPV_nolen(TOPs))
145 #define TOPn		(SvNV(TOPs))
146 #define TOPi		((IV)SvIV(TOPs))
147 #define TOPu		((UV)SvUV(TOPs))
148 #define TOPl		((long)SvIV(TOPs))
149 #define TOPul		((unsigned long)SvUV(TOPs))
150 #ifdef HAS_QUAD
151 #define TOPq		((Quad_t)SvIV(TOPs))
152 #define TOPuq		((Uquad_t)SvUV(TOPs))
153 #endif
154 
155 /* Go to some pains in the rare event that we must extend the stack. */
156 
157 /*
158 =for apidoc Am|void|EXTEND|SP|int nitems
159 Used to extend the argument stack for an XSUB's return values. Once
160 used, guarantees that there is room for at least C<nitems> to be pushed
161 onto the stack.
162 
163 =for apidoc Am|void|PUSHs|SV* sv
164 Push an SV onto the stack.  The stack must have room for this element.
165 Does not handle 'set' magic.  Does not use C<TARG>.  See also C<PUSHmortal>,
166 C<XPUSHs> and C<XPUSHmortal>.
167 
168 =for apidoc Am|void|PUSHp|char* str|STRLEN len
169 Push a string onto the stack.  The stack must have room for this element.
170 The C<len> indicates the length of the string.  Handles 'set' magic.  Uses
171 C<TARG>, so C<dTARGET> or C<dXSTARG> should be called to declare it.  Do not
172 call multiple C<TARG>-oriented macros to return lists from XSUB's - see
173 C<mPUSHp> instead.  See also C<XPUSHp> and C<mXPUSHp>.
174 
175 =for apidoc Am|void|PUSHn|NV nv
176 Push a double onto the stack.  The stack must have room for this element.
177 Handles 'set' magic.  Uses C<TARG>, so C<dTARGET> or C<dXSTARG> should be
178 called to declare it.  Do not call multiple C<TARG>-oriented macros to
179 return lists from XSUB's - see C<mPUSHn> instead.  See also C<XPUSHn> and
180 C<mXPUSHn>.
181 
182 =for apidoc Am|void|PUSHi|IV iv
183 Push an integer onto the stack.  The stack must have room for this element.
184 Handles 'set' magic.  Uses C<TARG>, so C<dTARGET> or C<dXSTARG> should be
185 called to declare it.  Do not call multiple C<TARG>-oriented macros to
186 return lists from XSUB's - see C<mPUSHi> instead.  See also C<XPUSHi> and
187 C<mXPUSHi>.
188 
189 =for apidoc Am|void|PUSHu|UV uv
190 Push an unsigned integer onto the stack.  The stack must have room for this
191 element.  Handles 'set' magic.  Uses C<TARG>, so C<dTARGET> or C<dXSTARG>
192 should be called to declare it.  Do not call multiple C<TARG>-oriented
193 macros to return lists from XSUB's - see C<mPUSHu> instead.  See also
194 C<XPUSHu> and C<mXPUSHu>.
195 
196 =for apidoc Am|void|XPUSHs|SV* sv
197 Push an SV onto the stack, extending the stack if necessary.  Does not
198 handle 'set' magic.  Does not use C<TARG>.  See also C<XPUSHmortal>,
199 C<PUSHs> and C<PUSHmortal>.
200 
201 =for apidoc Am|void|XPUSHp|char* str|STRLEN len
202 Push a string onto the stack, extending the stack if necessary.  The C<len>
203 indicates the length of the string.  Handles 'set' magic.  Uses C<TARG>, so
204 C<dTARGET> or C<dXSTARG> should be called to declare it.  Do not call
205 multiple C<TARG>-oriented macros to return lists from XSUB's - see
206 C<mXPUSHp> instead.  See also C<PUSHp> and C<mPUSHp>.
207 
208 =for apidoc Am|void|XPUSHn|NV nv
209 Push a double onto the stack, extending the stack if necessary.  Handles
210 'set' magic.  Uses C<TARG>, so C<dTARGET> or C<dXSTARG> should be called to
211 declare it.  Do not call multiple C<TARG>-oriented macros to return lists
212 from XSUB's - see C<mXPUSHn> instead.  See also C<PUSHn> and C<mPUSHn>.
213 
214 =for apidoc Am|void|XPUSHi|IV iv
215 Push an integer onto the stack, extending the stack if necessary.  Handles
216 'set' magic.  Uses C<TARG>, so C<dTARGET> or C<dXSTARG> should be called to
217 declare it.  Do not call multiple C<TARG>-oriented macros to return lists
218 from XSUB's - see C<mXPUSHi> instead.  See also C<PUSHi> and C<mPUSHi>.
219 
220 =for apidoc Am|void|XPUSHu|UV uv
221 Push an unsigned integer onto the stack, extending the stack if necessary.
222 Handles 'set' magic.  Uses C<TARG>, so C<dTARGET> or C<dXSTARG> should be
223 called to declare it.  Do not call multiple C<TARG>-oriented macros to
224 return lists from XSUB's - see C<mXPUSHu> instead.  See also C<PUSHu> and
225 C<mPUSHu>.
226 
227 =for apidoc Am|void|mPUSHs|SV* sv
228 Push an SV onto the stack and mortalizes the SV.  The stack must have room
229 for this element.  Does not use C<TARG>.  See also C<PUSHs> and C<mXPUSHs>.
230 
231 =for apidoc Am|void|PUSHmortal
232 Push a new mortal SV onto the stack.  The stack must have room for this
233 element.  Does not use C<TARG>.  See also C<PUSHs>, C<XPUSHmortal> and C<XPUSHs>.
234 
235 =for apidoc Am|void|mPUSHp|char* str|STRLEN len
236 Push a string onto the stack.  The stack must have room for this element.
237 The C<len> indicates the length of the string.  Does not use C<TARG>.
238 See also C<PUSHp>, C<mXPUSHp> and C<XPUSHp>.
239 
240 =for apidoc Am|void|mPUSHn|NV nv
241 Push a double onto the stack.  The stack must have room for this element.
242 Does not use C<TARG>.  See also C<PUSHn>, C<mXPUSHn> and C<XPUSHn>.
243 
244 =for apidoc Am|void|mPUSHi|IV iv
245 Push an integer onto the stack.  The stack must have room for this element.
246 Does not use C<TARG>.  See also C<PUSHi>, C<mXPUSHi> and C<XPUSHi>.
247 
248 =for apidoc Am|void|mPUSHu|UV uv
249 Push an unsigned integer onto the stack.  The stack must have room for this
250 element.  Does not use C<TARG>.  See also C<PUSHu>, C<mXPUSHu> and C<XPUSHu>.
251 
252 =for apidoc Am|void|mXPUSHs|SV* sv
253 Push an SV onto the stack, extending the stack if necessary and mortalizes
254 the SV.  Does not use C<TARG>.  See also C<XPUSHs> and C<mPUSHs>.
255 
256 =for apidoc Am|void|XPUSHmortal
257 Push a new mortal SV onto the stack, extending the stack if necessary.
258 Does not use C<TARG>.  See also C<XPUSHs>, C<PUSHmortal> and C<PUSHs>.
259 
260 =for apidoc Am|void|mXPUSHp|char* str|STRLEN len
261 Push a string onto the stack, extending the stack if necessary.  The C<len>
262 indicates the length of the string.  Does not use C<TARG>.  See also C<XPUSHp>,
263 C<mPUSHp> and C<PUSHp>.
264 
265 =for apidoc Am|void|mXPUSHn|NV nv
266 Push a double onto the stack, extending the stack if necessary.
267 Does not use C<TARG>.  See also C<XPUSHn>, C<mPUSHn> and C<PUSHn>.
268 
269 =for apidoc Am|void|mXPUSHi|IV iv
270 Push an integer onto the stack, extending the stack if necessary.
271 Does not use C<TARG>.  See also C<XPUSHi>, C<mPUSHi> and C<PUSHi>.
272 
273 =for apidoc Am|void|mXPUSHu|UV uv
274 Push an unsigned integer onto the stack, extending the stack if necessary.
275 Does not use C<TARG>.  See also C<XPUSHu>, C<mPUSHu> and C<PUSHu>.
276 
277 =cut
278 */
279 
280 #define EXTEND(p,n)	STMT_START { if (PL_stack_max - p < (int)(n)) {		\
281 			    sp = stack_grow(sp,p, (int) (n));		\
282 			} } STMT_END
283 
284 /* Same thing, but update mark register too. */
285 #define MEXTEND(p,n)	STMT_START {if (PL_stack_max - p < (int)(n)) {	\
286 			    const int markoff = mark - PL_stack_base;	\
287 			    sp = stack_grow(sp,p,(int) (n));		\
288 			    mark = PL_stack_base + markoff;		\
289 			} } STMT_END
290 
291 #define PUSHs(s)	(*++sp = (s))
292 #define PUSHTARG	STMT_START { SvSETMAGIC(TARG); PUSHs(TARG); } STMT_END
293 #define PUSHp(p,l)	STMT_START { sv_setpvn(TARG, (p), (l)); PUSHTARG; } STMT_END
294 #define PUSHn(n)	STMT_START { sv_setnv(TARG, (NV)(n)); PUSHTARG; } STMT_END
295 #define PUSHi(i)	STMT_START { sv_setiv(TARG, (IV)(i)); PUSHTARG; } STMT_END
296 #define PUSHu(u)	STMT_START { sv_setuv(TARG, (UV)(u)); PUSHTARG; } STMT_END
297 
298 #define XPUSHs(s)	STMT_START { EXTEND(sp,1); (*++sp = (s)); } STMT_END
299 #define XPUSHTARG	STMT_START { SvSETMAGIC(TARG); XPUSHs(TARG); } STMT_END
300 #define XPUSHp(p,l)	STMT_START { sv_setpvn(TARG, (p), (l)); XPUSHTARG; } STMT_END
301 #define XPUSHn(n)	STMT_START { sv_setnv(TARG, (NV)(n)); XPUSHTARG; } STMT_END
302 #define XPUSHi(i)	STMT_START { sv_setiv(TARG, (IV)(i)); XPUSHTARG; } STMT_END
303 #define XPUSHu(u)	STMT_START { sv_setuv(TARG, (UV)(u)); XPUSHTARG; } STMT_END
304 #define XPUSHundef	STMT_START { SvOK_off(TARG); XPUSHs(TARG); } STMT_END
305 
306 #define mPUSHs(s)	PUSHs(sv_2mortal(s))
307 #define PUSHmortal	PUSHs(sv_newmortal())
308 #define mPUSHp(p,l)	PUSHs(newSVpvn_flags((p), (l), SVs_TEMP))
309 #define mPUSHn(n)	sv_setnv(PUSHmortal, (NV)(n))
310 #define mPUSHi(i)	sv_setiv(PUSHmortal, (IV)(i))
311 #define mPUSHu(u)	sv_setuv(PUSHmortal, (UV)(u))
312 
313 #define mXPUSHs(s)	XPUSHs(sv_2mortal(s))
314 #define XPUSHmortal	XPUSHs(sv_newmortal())
315 #define mXPUSHp(p,l)	STMT_START { EXTEND(sp,1); mPUSHp((p), (l)); } STMT_END
316 #define mXPUSHn(n)	STMT_START { EXTEND(sp,1); sv_setnv(PUSHmortal, (NV)(n)); } STMT_END
317 #define mXPUSHi(i)	STMT_START { EXTEND(sp,1); sv_setiv(PUSHmortal, (IV)(i)); } STMT_END
318 #define mXPUSHu(u)	STMT_START { EXTEND(sp,1); sv_setuv(PUSHmortal, (UV)(u)); } STMT_END
319 
320 #define SETs(s)		(*sp = s)
321 #define SETTARG		STMT_START { SvSETMAGIC(TARG); SETs(TARG); } STMT_END
322 #define SETp(p,l)	STMT_START { sv_setpvn(TARG, (p), (l)); SETTARG; } STMT_END
323 #define SETn(n)		STMT_START { sv_setnv(TARG, (NV)(n)); SETTARG; } STMT_END
324 #define SETi(i)		STMT_START { sv_setiv(TARG, (IV)(i)); SETTARG; } STMT_END
325 #define SETu(u)		STMT_START { sv_setuv(TARG, (UV)(u)); SETTARG; } STMT_END
326 
327 #define dTOPss		SV *sv = TOPs
328 #define dPOPss		SV *sv = POPs
329 #define dTOPnv		NV value = TOPn
330 #define dPOPnv		NV value = POPn
331 #define dTOPiv		IV value = TOPi
332 #define dPOPiv		IV value = POPi
333 #define dTOPuv		UV value = TOPu
334 #define dPOPuv		UV value = POPu
335 #ifdef HAS_QUAD
336 #define dTOPqv		Quad_t value = TOPu
337 #define dPOPqv		Quad_t value = POPu
338 #define dTOPuqv		Uquad_t value = TOPuq
339 #define dPOPuqv		Uquad_t value = POPuq
340 #endif
341 
342 #define dPOPXssrl(X)	SV *right = POPs; SV *left = CAT2(X,s)
343 #define dPOPXnnrl(X)	NV right = POPn; NV left = CAT2(X,n)
344 #define dPOPXiirl(X)	IV right = POPi; IV left = CAT2(X,i)
345 
346 #define USE_LEFT(sv) \
347 	(SvOK(sv) || SvGMAGICAL(sv) || !(PL_op->op_flags & OPf_STACKED))
348 #define dPOPXnnrl_ul(X)	\
349     NV right = POPn;				\
350     SV *leftsv = CAT2(X,s);				\
351     NV left = USE_LEFT(leftsv) ? SvNV(leftsv) : 0.0
352 #define dPOPXiirl_ul(X) \
353     IV right = POPi;					\
354     SV *leftsv = CAT2(X,s);				\
355     IV left = USE_LEFT(leftsv) ? SvIV(leftsv) : 0
356 
357 #define dPOPPOPssrl	dPOPXssrl(POP)
358 #define dPOPPOPnnrl	dPOPXnnrl(POP)
359 #define dPOPPOPnnrl_ul	dPOPXnnrl_ul(POP)
360 #define dPOPPOPiirl	dPOPXiirl(POP)
361 #define dPOPPOPiirl_ul	dPOPXiirl_ul(POP)
362 
363 #define dPOPTOPssrl	dPOPXssrl(TOP)
364 #define dPOPTOPnnrl	dPOPXnnrl(TOP)
365 #define dPOPTOPnnrl_ul	dPOPXnnrl_ul(TOP)
366 #define dPOPTOPiirl	dPOPXiirl(TOP)
367 #define dPOPTOPiirl_ul	dPOPXiirl_ul(TOP)
368 
369 #define RETPUSHYES	RETURNX(PUSHs(&PL_sv_yes))
370 #define RETPUSHNO	RETURNX(PUSHs(&PL_sv_no))
371 #define RETPUSHUNDEF	RETURNX(PUSHs(&PL_sv_undef))
372 
373 #define RETSETYES	RETURNX(SETs(&PL_sv_yes))
374 #define RETSETNO	RETURNX(SETs(&PL_sv_no))
375 #define RETSETUNDEF	RETURNX(SETs(&PL_sv_undef))
376 
377 #define ARGTARG		PL_op->op_targ
378 
379     /* See OPpTARGET_MY: */
380 #define MAXARG		(PL_op->op_private & 15)
381 
382 #define SWITCHSTACK(f,t) \
383     STMT_START {							\
384 	AvFILLp(f) = sp - PL_stack_base;				\
385 	PL_stack_base = AvARRAY(t);					\
386 	PL_stack_max = PL_stack_base + AvMAX(t);			\
387 	sp = PL_stack_sp = PL_stack_base + AvFILLp(t);			\
388 	PL_curstack = t;						\
389     } STMT_END
390 
391 #define EXTEND_MORTAL(n) \
392     STMT_START {							\
393 	if (PL_tmps_ix + (n) >= PL_tmps_max)				\
394 	    tmps_grow(n);						\
395     } STMT_END
396 
397 #define AMGf_noright	1
398 #define AMGf_noleft	2
399 #define AMGf_assign	4
400 #define AMGf_unary	8
401 
402 #define tryAMAGICbinW_var(meth_enum,assign,set) STMT_START { \
403 	    SV* const left = *(sp-1); \
404 	    SV* const right = *(sp); \
405 	    if ((SvAMAGIC(left)||SvAMAGIC(right))) {\
406 		SV * const tmpsv = amagic_call(left, \
407 				   right, \
408 				   (meth_enum), \
409 				   (assign)? AMGf_assign: 0); \
410 		if (tmpsv) { \
411 		    SPAGAIN; \
412 		    (void)POPs; set(tmpsv); RETURN; } \
413 		} \
414 	} STMT_END
415 
416 #define tryAMAGICbinW(meth,assign,set) \
417     tryAMAGICbinW_var(CAT2(meth,_amg),assign,set)
418 
419 #define tryAMAGICbin_var(meth_enum,assign) \
420 		tryAMAGICbinW_var(meth_enum,assign,SETsv)
421 #define tryAMAGICbin(meth,assign) \
422 		tryAMAGICbin_var(CAT2(meth,_amg),assign)
423 
424 #define tryAMAGICbinSET(meth,assign) tryAMAGICbinW(meth,assign,SETs)
425 
426 #define tryAMAGICbinSET_var(meth_enum,assign) \
427     tryAMAGICbinW_var(meth_enum,assign,SETs)
428 
429 #define AMG_CALLun_var(sv,meth_enum) amagic_call(sv,&PL_sv_undef,  \
430 					meth_enum,AMGf_noright | AMGf_unary)
431 #define AMG_CALLun(sv,meth) AMG_CALLun_var(sv,CAT2(meth,_amg))
432 
433 #define AMG_CALLbinL(left,right,meth) \
434             amagic_call(left,right,CAT2(meth,_amg),AMGf_noright)
435 
436 #define tryAMAGICunW_var(meth_enum,set,shift,ret) STMT_START { \
437 	    SV* tmpsv; \
438 	    SV* arg= sp[shift]; \
439           if(0) goto am_again;  /* shut up unused warning */ \
440 	  am_again: \
441 	    if ((SvAMAGIC(arg))&&\
442 		(tmpsv=AMG_CALLun_var(arg,(meth_enum)))) {\
443 	       SPAGAIN; if (shift) sp += shift; \
444 	       set(tmpsv); ret; } \
445 	} STMT_END
446 #define tryAMAGICunW(meth,set,shift,ret) \
447 	tryAMAGICunW_var(CAT2(meth,_amg),set,shift,ret)
448 
449 #define FORCE_SETs(sv) STMT_START { sv_setsv(TARG, (sv)); SETTARG; } STMT_END
450 
451 #define tryAMAGICun_var(meth_enum) tryAMAGICunW_var(meth_enum,SETsvUN,0,RETURN)
452 #define tryAMAGICun(meth)	tryAMAGICun_var(CAT2(meth,_amg))
453 #define tryAMAGICunSET(meth)	tryAMAGICunW(meth,SETs,0,RETURN)
454 #define tryAMAGICunTARGET(meth, shift)					\
455 	STMT_START { dSP; sp--; 	/* get TARGET from below PL_stack_sp */		\
456 	    { dTARGETSTACKED; 						\
457 		{ dSP; tryAMAGICunW(meth,FORCE_SETs,shift,RETURN);}}} STMT_END
458 
459 #define setAGAIN(ref)	\
460     STMT_START {					\
461 	sv = ref;					\
462 	if (!SvROK(ref))				\
463 	    Perl_croak(aTHX_ "Overloaded dereference did not return a reference");	\
464 	if (ref != arg && SvRV(ref) != SvRV(arg)) {	\
465 	    arg = ref;					\
466 	    goto am_again;				\
467 	}						\
468     } STMT_END
469 
470 #define tryAMAGICunDEREF(meth) tryAMAGICunW(meth,setAGAIN,0,(void)0)
471 #define tryAMAGICunDEREF_var(meth_enum) \
472 	tryAMAGICunW_var(meth_enum,setAGAIN,0,(void)0)
473 
474 #define tryAMAGICftest(chr)				\
475     STMT_START {					\
476 	assert(chr != '?');				\
477 	if ((PL_op->op_flags & OPf_KIDS)		\
478 		&& SvAMAGIC(TOPs)) {			\
479 	    const char tmpchr = (chr);			\
480 	    SV * const tmpsv = amagic_call(TOPs,	\
481 		newSVpvn_flags(&tmpchr, 1, SVs_TEMP),	\
482 		ftest_amg, AMGf_unary);			\
483 							\
484 	    if (tmpsv) {				\
485 		const OP *next = PL_op->op_next;	\
486 							\
487 		SPAGAIN;				\
488 							\
489 		if (next->op_type >= OP_FTRREAD &&	\
490 		    next->op_type <= OP_FTBINARY &&	\
491 		    next->op_private & OPpFT_STACKED	\
492 		) {					\
493 		    if (SvTRUE(tmpsv))			\
494 			/* leave the object alone */	\
495 			RETURN;				\
496 		}					\
497 							\
498 		SETs(tmpsv);				\
499 		RETURN;					\
500 	    }						\
501 	}						\
502     } STMT_END
503 
504 
505 #define opASSIGN (PL_op->op_flags & OPf_STACKED)
506 #define SETsv(sv)	STMT_START {					\
507 		if (opASSIGN || (SvFLAGS(TARG) & SVs_PADMY))		\
508 		   { sv_setsv(TARG, (sv)); SETTARG; }			\
509 		else SETs(sv); } STMT_END
510 
511 #define SETsvUN(sv)	STMT_START {					\
512 		if (SvFLAGS(TARG) & SVs_PADMY)		\
513 		   { sv_setsv(TARG, (sv)); SETTARG; }			\
514 		else SETs(sv); } STMT_END
515 
516 /* newSVsv does not behave as advertised, so we copy missing
517  * information by hand */
518 
519 /* SV* ref causes confusion with the member variable
520    changed SV* ref to SV* tmpRef */
521 #define RvDEEPCP(rv) STMT_START { SV* tmpRef=SvRV(rv); SV* rv_copy;     \
522   if (SvREFCNT(tmpRef)>1 && (rv_copy = AMG_CALLun(rv,copy))) {          \
523     SvRV_set(rv, rv_copy);		    \
524     SvREFCNT_dec(tmpRef);                   \
525   } } STMT_END
526 
527 /*
528 =for apidoc mU||LVRET
529 True if this op will be the return value of an lvalue subroutine
530 
531 =cut */
532 #define LVRET ((PL_op->op_private & OPpMAYBE_LVSUB) && is_lvalue_sub())
533 
534 #define SvCANEXISTDELETE(sv) \
535  (!SvRMAGICAL(sv)            \
536   || ((mg = mg_find((const SV *) sv, PERL_MAGIC_tied))           \
537       && (stash = SvSTASH(SvRV(SvTIED_obj(MUTABLE_SV(sv), mg)))) \
538       && gv_fetchmethod_autoload(stash, "EXISTS", TRUE)          \
539       && gv_fetchmethod_autoload(stash, "DELETE", TRUE)          \
540      )                       \
541   )
542 
543 /*
544  * Local variables:
545  * c-indentation-style: bsd
546  * c-basic-offset: 4
547  * indent-tabs-mode: t
548  * End:
549  *
550  * ex: set ts=8 sts=4 sw=4 noet:
551  */
552