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op.c
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op.c
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#line 2 "op.c"
/* op.c
*
* Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
* 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 by Larry Wall and others
*
* You may distribute under the terms of either the GNU General Public
* License or the Artistic License, as specified in the README file.
*
*/
/*
* 'You see: Mr. Drogo, he married poor Miss Primula Brandybuck. She was
* our Mr. Bilbo's first cousin on the mother's side (her mother being the
* youngest of the Old Took's daughters); and Mr. Drogo was his second
* cousin. So Mr. Frodo is his first *and* second cousin, once removed
* either way, as the saying is, if you follow me.' --the Gaffer
*
* [p.23 of _The Lord of the Rings_, I/i: "A Long-Expected Party"]
*/
/* This file contains the functions that create, manipulate and optimize
* the OP structures that hold a compiled perl program.
*
* A Perl program is compiled into a tree of OPs. Each op contains
* structural pointers (eg to its siblings and the next op in the
* execution sequence), a pointer to the function that would execute the
* op, plus any data specific to that op. For example, an OP_CONST op
* points to the pp_const() function and to an SV containing the constant
* value. When pp_const() is executed, its job is to push that SV onto the
* stack.
*
* OPs are mainly created by the newFOO() functions, which are mainly
* called from the parser (in perly.y) as the code is parsed. For example
* the Perl code $a + $b * $c would cause the equivalent of the following
* to be called (oversimplifying a bit):
*
* newBINOP(OP_ADD, flags,
* newSVREF($a),
* newBINOP(OP_MULTIPLY, flags, newSVREF($b), newSVREF($c))
* )
*
* Note that during the build of miniperl, a temporary copy of this file
* is made, called opmini.c.
*/
/*
Perl's compiler is essentially a 3-pass compiler with interleaved phases:
A bottom-up pass
A top-down pass
An execution-order pass
The bottom-up pass is represented by all the "newOP" routines and
the ck_ routines. The bottom-upness is actually driven by yacc.
So at the point that a ck_ routine fires, we have no idea what the
context is, either upward in the syntax tree, or either forward or
backward in the execution order. (The bottom-up parser builds that
part of the execution order it knows about, but if you follow the "next"
links around, you'll find it's actually a closed loop through the
top level node.)
Whenever the bottom-up parser gets to a node that supplies context to
its components, it invokes that portion of the top-down pass that applies
to that part of the subtree (and marks the top node as processed, so
if a node further up supplies context, it doesn't have to take the
plunge again). As a particular subcase of this, as the new node is
built, it takes all the closed execution loops of its subcomponents
and links them into a new closed loop for the higher level node. But
it's still not the real execution order.
The actual execution order is not known till we get a grammar reduction
to a top-level unit like a subroutine or file that will be called by
"name" rather than via a "next" pointer. At that point, we can call
into peep() to do that code's portion of the 3rd pass. It has to be
recursive, but it's recursive on basic blocks, not on tree nodes.
*/
/* To implement user lexical pragmas, there needs to be a way at run time to
get the compile time state of %^H for that block. Storing %^H in every
block (or even COP) would be very expensive, so a different approach is
taken. The (running) state of %^H is serialised into a tree of HE-like
structs. Stores into %^H are chained onto the current leaf as a struct
refcounted_he * with the key and the value. Deletes from %^H are saved
with a value of PL_sv_placeholder. The state of %^H at any point can be
turned back into a regular HV by walking back up the tree from that point's
leaf, ignoring any key you've already seen (placeholder or not), storing
the rest into the HV structure, then removing the placeholders. Hence
memory is only used to store the %^H deltas from the enclosing COP, rather
than the entire %^H on each COP.
To cause actions on %^H to write out the serialisation records, it has
magic type 'H'. This magic (itself) does nothing, but its presence causes
the values to gain magic type 'h', which has entries for set and clear.
C<Perl_magic_sethint> updates C<PL_compiling.cop_hints_hash> with a store
record, with deletes written by C<Perl_magic_clearhint>. C<SAVEHINTS>
saves the current C<PL_compiling.cop_hints_hash> on the save stack, so that
it will be correctly restored when any inner compiling scope is exited.
*/
#include "EXTERN.h"
#define PERL_IN_OP_C
#include "perl.h"
#include "keywords.h"
#define CALL_PEEP(o) CALL_FPTR(PL_peepp)(aTHX_ o)
#define CALL_OPFREEHOOK(o) if (PL_opfreehook) CALL_FPTR(PL_opfreehook)(aTHX_ o)
#if defined(PL_OP_SLAB_ALLOC)
#ifdef PERL_DEBUG_READONLY_OPS
# define PERL_SLAB_SIZE 4096
# include <sys/mman.h>
#endif
#ifndef PERL_SLAB_SIZE
#define PERL_SLAB_SIZE 2048
#endif
void *
Perl_Slab_Alloc(pTHX_ size_t sz)
{
dVAR;
/*
* To make incrementing use count easy PL_OpSlab is an I32 *
* To make inserting the link to slab PL_OpPtr is I32 **
* So compute size in units of sizeof(I32 *) as that is how Pl_OpPtr increments
* Add an overhead for pointer to slab and round up as a number of pointers
*/
sz = (sz + 2*sizeof(I32 *) -1)/sizeof(I32 *);
if ((PL_OpSpace -= sz) < 0) {
#ifdef PERL_DEBUG_READONLY_OPS
/* We need to allocate chunk by chunk so that we can control the VM
mapping */
PL_OpPtr = (I32**) mmap(0, PERL_SLAB_SIZE*sizeof(I32*), PROT_READ|PROT_WRITE,
MAP_ANON|MAP_PRIVATE, -1, 0);
DEBUG_m(PerlIO_printf(Perl_debug_log, "mapped %lu at %p\n",
(unsigned long) PERL_SLAB_SIZE*sizeof(I32*),
PL_OpPtr));
if(PL_OpPtr == MAP_FAILED) {
perror("mmap failed");
abort();
}
#else
PL_OpPtr = (I32 **) PerlMemShared_calloc(PERL_SLAB_SIZE,sizeof(I32*));
#endif
if (!PL_OpPtr) {
return NULL;
}
/* We reserve the 0'th I32 sized chunk as a use count */
PL_OpSlab = (I32 *) PL_OpPtr;
/* Reduce size by the use count word, and by the size we need.
* Latter is to mimic the '-=' in the if() above
*/
PL_OpSpace = PERL_SLAB_SIZE - (sizeof(I32)+sizeof(I32 **)-1)/sizeof(I32 **) - sz;
/* Allocation pointer starts at the top.
Theory: because we build leaves before trunk allocating at end
means that at run time access is cache friendly upward
*/
PL_OpPtr += PERL_SLAB_SIZE;
#ifdef PERL_DEBUG_READONLY_OPS
/* We remember this slab. */
/* This implementation isn't efficient, but it is simple. */
PL_slabs = (I32**) realloc(PL_slabs, sizeof(I32**) * (PL_slab_count + 1));
PL_slabs[PL_slab_count++] = PL_OpSlab;
DEBUG_m(PerlIO_printf(Perl_debug_log, "Allocate %p\n", PL_OpSlab));
#endif
}
assert( PL_OpSpace >= 0 );
/* Move the allocation pointer down */
PL_OpPtr -= sz;
assert( PL_OpPtr > (I32 **) PL_OpSlab );
*PL_OpPtr = PL_OpSlab; /* Note which slab it belongs to */
(*PL_OpSlab)++; /* Increment use count of slab */
assert( PL_OpPtr+sz <= ((I32 **) PL_OpSlab + PERL_SLAB_SIZE) );
assert( *PL_OpSlab > 0 );
return (void *)(PL_OpPtr + 1);
}
#ifdef PERL_DEBUG_READONLY_OPS
void
Perl_pending_Slabs_to_ro(pTHX) {
/* Turn all the allocated op slabs read only. */
U32 count = PL_slab_count;
I32 **const slabs = PL_slabs;
/* Reset the array of pending OP slabs, as we're about to turn this lot
read only. Also, do it ahead of the loop in case the warn triggers,
and a warn handler has an eval */
PL_slabs = NULL;
PL_slab_count = 0;
/* Force a new slab for any further allocation. */
PL_OpSpace = 0;
while (count--) {
void *const start = slabs[count];
const size_t size = PERL_SLAB_SIZE* sizeof(I32*);
if(mprotect(start, size, PROT_READ)) {
Perl_warn(aTHX_ "mprotect for %p %lu failed with %d",
start, (unsigned long) size, errno);
}
}
free(slabs);
}
STATIC void
S_Slab_to_rw(pTHX_ void *op)
{
I32 * const * const ptr = (I32 **) op;
I32 * const slab = ptr[-1];
PERL_ARGS_ASSERT_SLAB_TO_RW;
assert( ptr-1 > (I32 **) slab );
assert( ptr < ( (I32 **) slab + PERL_SLAB_SIZE) );
assert( *slab > 0 );
if(mprotect(slab, PERL_SLAB_SIZE*sizeof(I32*), PROT_READ|PROT_WRITE)) {
Perl_warn(aTHX_ "mprotect RW for %p %lu failed with %d",
slab, (unsigned long) PERL_SLAB_SIZE*sizeof(I32*), errno);
}
}
OP *
Perl_op_refcnt_inc(pTHX_ OP *o)
{
if(o) {
Slab_to_rw(o);
++o->op_targ;
}
return o;
}
PADOFFSET
Perl_op_refcnt_dec(pTHX_ OP *o)
{
PERL_ARGS_ASSERT_OP_REFCNT_DEC;
Slab_to_rw(o);
return --o->op_targ;
}
#else
# define Slab_to_rw(op)
#endif
void
Perl_Slab_Free(pTHX_ void *op)
{
I32 * const * const ptr = (I32 **) op;
I32 * const slab = ptr[-1];
PERL_ARGS_ASSERT_SLAB_FREE;
assert( ptr-1 > (I32 **) slab );
assert( ptr < ( (I32 **) slab + PERL_SLAB_SIZE) );
assert( *slab > 0 );
Slab_to_rw(op);
if (--(*slab) == 0) {
# ifdef NETWARE
# define PerlMemShared PerlMem
# endif
#ifdef PERL_DEBUG_READONLY_OPS
U32 count = PL_slab_count;
/* Need to remove this slab from our list of slabs */
if (count) {
while (count--) {
if (PL_slabs[count] == slab) {
dVAR;
/* Found it. Move the entry at the end to overwrite it. */
DEBUG_m(PerlIO_printf(Perl_debug_log,
"Deallocate %p by moving %p from %lu to %lu\n",
PL_OpSlab,
PL_slabs[PL_slab_count - 1],
PL_slab_count, count));
PL_slabs[count] = PL_slabs[--PL_slab_count];
/* Could realloc smaller at this point, but probably not
worth it. */
if(munmap(slab, PERL_SLAB_SIZE*sizeof(I32*))) {
perror("munmap failed");
abort();
}
break;
}
}
}
#else
PerlMemShared_free(slab);
#endif
if (slab == PL_OpSlab) {
PL_OpSpace = 0;
}
}
}
#endif
/*
* In the following definition, the ", (OP*)0" is just to make the compiler
* think the expression is of the right type: croak actually does a Siglongjmp.
*/
#define CHECKOP(type,o) \
((PL_op_mask && PL_op_mask[type]) \
? ( op_free((OP*)o), \
Perl_croak(aTHX_ "'%s' trapped by operation mask", PL_op_desc[type]), \
(OP*)0 ) \
: CALL_FPTR(PL_check[type])(aTHX_ (OP*)o))
#define RETURN_UNLIMITED_NUMBER (PERL_INT_MAX / 2)
STATIC const char*
S_gv_ename(pTHX_ GV *gv)
{
SV* const tmpsv = sv_newmortal();
PERL_ARGS_ASSERT_GV_ENAME;
gv_efullname3(tmpsv, gv, NULL);
return SvPV_nolen_const(tmpsv);
}
STATIC OP *
S_no_fh_allowed(pTHX_ OP *o)
{
PERL_ARGS_ASSERT_NO_FH_ALLOWED;
yyerror(Perl_form(aTHX_ "Missing comma after first argument to %s function",
OP_DESC(o)));
return o;
}
STATIC OP *
S_too_few_arguments(pTHX_ OP *o, const char *name)
{
PERL_ARGS_ASSERT_TOO_FEW_ARGUMENTS;
yyerror(Perl_form(aTHX_ "Not enough arguments for %s", name));
return o;
}
STATIC OP *
S_too_many_arguments(pTHX_ OP *o, const char *name)
{
PERL_ARGS_ASSERT_TOO_MANY_ARGUMENTS;
yyerror(Perl_form(aTHX_ "Too many arguments for %s", name));
return o;
}
STATIC void
S_bad_type(pTHX_ I32 n, const char *t, const char *name, const OP *kid)
{
PERL_ARGS_ASSERT_BAD_TYPE;
yyerror(Perl_form(aTHX_ "Type of arg %d to %s must be %s (not %s)",
(int)n, name, t, OP_DESC(kid)));
}
STATIC void
S_no_bareword_allowed(pTHX_ const OP *o)
{
PERL_ARGS_ASSERT_NO_BAREWORD_ALLOWED;
if (PL_madskills)
return; /* various ok barewords are hidden in extra OP_NULL */
qerror(Perl_mess(aTHX_
"Bareword \"%"SVf"\" not allowed while \"strict subs\" in use",
SVfARG(cSVOPo_sv)));
}
/* "register" allocation */
PADOFFSET
Perl_allocmy(pTHX_ const char *const name, const STRLEN len, const U32 flags)
{
dVAR;
PADOFFSET off;
const bool is_our = (PL_parser->in_my == KEY_our);
PERL_ARGS_ASSERT_ALLOCMY;
if (flags)
Perl_croak(aTHX_ "panic: allocmy illegal flag bits 0x%" UVxf,
(UV)flags);
/* Until we're using the length for real, cross check that we're being
told the truth. */
assert(strlen(name) == len);
/* complain about "my $<special_var>" etc etc */
if (len &&
!(is_our ||
isALPHA(name[1]) ||
(USE_UTF8_IN_NAMES && UTF8_IS_START(name[1])) ||
(name[1] == '_' && (*name == '$' || len > 2))))
{
/* name[2] is true if strlen(name) > 2 */
if (!isPRINT(name[1]) || strchr("\t\n\r\f", name[1])) {
yyerror(Perl_form(aTHX_ "Can't use global %c^%c%.*s in \"%s\"",
name[0], toCTRL(name[1]), (int)(len - 2), name + 2,
PL_parser->in_my == KEY_state ? "state" : "my"));
} else {
yyerror(Perl_form(aTHX_ "Can't use global %.*s in \"%s\"", (int) len, name,
PL_parser->in_my == KEY_state ? "state" : "my"));
}
}
/* allocate a spare slot and store the name in that slot */
off = pad_add_name(name, len,
is_our ? padadd_OUR :
PL_parser->in_my == KEY_state ? padadd_STATE : 0,
PL_parser->in_my_stash,
(is_our
/* $_ is always in main::, even with our */
? (PL_curstash && !strEQ(name,"$_") ? PL_curstash : PL_defstash)
: NULL
)
);
/* anon sub prototypes contains state vars should always be cloned,
* otherwise the state var would be shared between anon subs */
if (PL_parser->in_my == KEY_state && CvANON(PL_compcv))
CvCLONE_on(PL_compcv);
return off;
}
/* free the body of an op without examining its contents.
* Always use this rather than FreeOp directly */
static void
S_op_destroy(pTHX_ OP *o)
{
if (o->op_latefree) {
o->op_latefreed = 1;
return;
}
FreeOp(o);
}
#ifdef USE_ITHREADS
# define forget_pmop(a,b) S_forget_pmop(aTHX_ a,b)
#else
# define forget_pmop(a,b) S_forget_pmop(aTHX_ a)
#endif
/* Destructor */
void
Perl_op_free(pTHX_ OP *o)
{
dVAR;
OPCODE type;
if (!o)
return;
if (o->op_latefreed) {
if (o->op_latefree)
return;
goto do_free;
}
type = o->op_type;
if (o->op_private & OPpREFCOUNTED) {
switch (type) {
case OP_LEAVESUB:
case OP_LEAVESUBLV:
case OP_LEAVEEVAL:
case OP_LEAVE:
case OP_SCOPE:
case OP_LEAVEWRITE:
{
PADOFFSET refcnt;
OP_REFCNT_LOCK;
refcnt = OpREFCNT_dec(o);
OP_REFCNT_UNLOCK;
if (refcnt) {
/* Need to find and remove any pattern match ops from the list
we maintain for reset(). */
find_and_forget_pmops(o);
return;
}
}
break;
default:
break;
}
}
/* Call the op_free hook if it has been set. Do it now so that it's called
* at the right time for refcounted ops, but still before all of the kids
* are freed. */
CALL_OPFREEHOOK(o);
if (o->op_flags & OPf_KIDS) {
register OP *kid, *nextkid;
for (kid = cUNOPo->op_first; kid; kid = nextkid) {
nextkid = kid->op_sibling; /* Get before next freeing kid */
op_free(kid);
}
}
#ifdef PERL_DEBUG_READONLY_OPS
Slab_to_rw(o);
#endif
/* COP* is not cleared by op_clear() so that we may track line
* numbers etc even after null() */
if (type == OP_NEXTSTATE || type == OP_DBSTATE
|| (type == OP_NULL /* the COP might have been null'ed */
&& ((OPCODE)o->op_targ == OP_NEXTSTATE
|| (OPCODE)o->op_targ == OP_DBSTATE))) {
cop_free((COP*)o);
}
if (type == OP_NULL)
type = (OPCODE)o->op_targ;
op_clear(o);
if (o->op_latefree) {
o->op_latefreed = 1;
return;
}
do_free:
FreeOp(o);
#ifdef DEBUG_LEAKING_SCALARS
if (PL_op == o)
PL_op = NULL;
#endif
}
void
Perl_op_clear(pTHX_ OP *o)
{
dVAR;
PERL_ARGS_ASSERT_OP_CLEAR;
#ifdef PERL_MAD
/* if (o->op_madprop && o->op_madprop->mad_next)
abort(); */
/* FIXME for MAD - if I uncomment these two lines t/op/pack.t fails with
"modification of a read only value" for a reason I can't fathom why.
It's the "" stringification of $_, where $_ was set to '' in a foreach
loop, but it defies simplification into a small test case.
However, commenting them out has caused ext/List/Util/t/weak.t to fail
the last test. */
/*
mad_free(o->op_madprop);
o->op_madprop = 0;
*/
#endif
retry:
switch (o->op_type) {
case OP_NULL: /* Was holding old type, if any. */
if (PL_madskills && o->op_targ != OP_NULL) {
o->op_type = (Optype)o->op_targ;
o->op_targ = 0;
goto retry;
}
case OP_ENTERTRY:
case OP_ENTEREVAL: /* Was holding hints. */
o->op_targ = 0;
break;
default:
if (!(o->op_flags & OPf_REF)
|| (PL_check[o->op_type] != MEMBER_TO_FPTR(Perl_ck_ftst)))
break;
/* FALL THROUGH */
case OP_GVSV:
case OP_GV:
case OP_AELEMFAST:
if (! (o->op_type == OP_AELEMFAST && o->op_flags & OPf_SPECIAL)) {
/* not an OP_PADAV replacement */
GV *gv = (o->op_type == OP_GV || o->op_type == OP_GVSV)
#ifdef USE_ITHREADS
&& PL_curpad
#endif
? cGVOPo_gv : NULL;
/* It's possible during global destruction that the GV is freed
before the optree. Whilst the SvREFCNT_inc is happy to bump from
0 to 1 on a freed SV, the corresponding SvREFCNT_dec from 1 to 0
will trigger an assertion failure, because the entry to sv_clear
checks that the scalar is not already freed. A check of for
!SvIS_FREED(gv) turns out to be invalid, because during global
destruction the reference count can be forced down to zero
(with SVf_BREAK set). In which case raising to 1 and then
dropping to 0 triggers cleanup before it should happen. I
*think* that this might actually be a general, systematic,
weakness of the whole idea of SVf_BREAK, in that code *is*
allowed to raise and lower references during global destruction,
so any *valid* code that happens to do this during global
destruction might well trigger premature cleanup. */
bool still_valid = gv && SvREFCNT(gv);
if (still_valid)
SvREFCNT_inc_simple_void(gv);
#ifdef USE_ITHREADS
if (cPADOPo->op_padix > 0) {
/* No GvIN_PAD_off(cGVOPo_gv) here, because other references
* may still exist on the pad */
pad_swipe(cPADOPo->op_padix, TRUE);
cPADOPo->op_padix = 0;
}
#else
SvREFCNT_dec(cSVOPo->op_sv);
cSVOPo->op_sv = NULL;
#endif
if (still_valid) {
int try_downgrade = SvREFCNT(gv) == 2;
SvREFCNT_dec(gv);
if (try_downgrade)
gv_try_downgrade(gv);
}
}
break;
case OP_METHOD_NAMED:
case OP_CONST:
case OP_HINTSEVAL:
SvREFCNT_dec(cSVOPo->op_sv);
cSVOPo->op_sv = NULL;
#ifdef USE_ITHREADS
/** Bug #15654
Even if op_clear does a pad_free for the target of the op,
pad_free doesn't actually remove the sv that exists in the pad;
instead it lives on. This results in that it could be reused as
a target later on when the pad was reallocated.
**/
if(o->op_targ) {
pad_swipe(o->op_targ,1);
o->op_targ = 0;
}
#endif
break;
case OP_GOTO:
case OP_NEXT:
case OP_LAST:
case OP_REDO:
if (o->op_flags & (OPf_SPECIAL|OPf_STACKED|OPf_KIDS))
break;
/* FALL THROUGH */
case OP_TRANS:
if (o->op_private & (OPpTRANS_FROM_UTF|OPpTRANS_TO_UTF)) {
#ifdef USE_ITHREADS
if (cPADOPo->op_padix > 0) {
pad_swipe(cPADOPo->op_padix, TRUE);
cPADOPo->op_padix = 0;
}
#else
SvREFCNT_dec(cSVOPo->op_sv);
cSVOPo->op_sv = NULL;
#endif
}
else {
PerlMemShared_free(cPVOPo->op_pv);
cPVOPo->op_pv = NULL;
}
break;
case OP_SUBST:
op_free(cPMOPo->op_pmreplrootu.op_pmreplroot);
goto clear_pmop;
case OP_PUSHRE:
#ifdef USE_ITHREADS
if (cPMOPo->op_pmreplrootu.op_pmtargetoff) {
/* No GvIN_PAD_off here, because other references may still
* exist on the pad */
pad_swipe(cPMOPo->op_pmreplrootu.op_pmtargetoff, TRUE);
}
#else
SvREFCNT_dec(MUTABLE_SV(cPMOPo->op_pmreplrootu.op_pmtargetgv));
#endif
/* FALL THROUGH */
case OP_MATCH:
case OP_QR:
clear_pmop:
forget_pmop(cPMOPo, 1);
cPMOPo->op_pmreplrootu.op_pmreplroot = NULL;
/* we use the same protection as the "SAFE" version of the PM_ macros
* here since sv_clean_all might release some PMOPs
* after PL_regex_padav has been cleared
* and the clearing of PL_regex_padav needs to
* happen before sv_clean_all
*/
#ifdef USE_ITHREADS
if(PL_regex_pad) { /* We could be in destruction */
const IV offset = (cPMOPo)->op_pmoffset;
ReREFCNT_dec(PM_GETRE(cPMOPo));
PL_regex_pad[offset] = &PL_sv_undef;
sv_catpvn_nomg(PL_regex_pad[0], (const char *)&offset,
sizeof(offset));
}
#else
ReREFCNT_dec(PM_GETRE(cPMOPo));
PM_SETRE(cPMOPo, NULL);
#endif
break;
}
if (o->op_targ > 0) {
pad_free(o->op_targ);
o->op_targ = 0;
}
}
STATIC void
S_cop_free(pTHX_ COP* cop)
{
PERL_ARGS_ASSERT_COP_FREE;
CopFILE_free(cop);
CopSTASH_free(cop);
if (! specialWARN(cop->cop_warnings))
PerlMemShared_free(cop->cop_warnings);
Perl_refcounted_he_free(aTHX_ cop->cop_hints_hash);
}
STATIC void
S_forget_pmop(pTHX_ PMOP *const o
#ifdef USE_ITHREADS
, U32 flags
#endif
)
{
HV * const pmstash = PmopSTASH(o);
PERL_ARGS_ASSERT_FORGET_PMOP;
if (pmstash && !SvIS_FREED(pmstash)) {
MAGIC * const mg = mg_find((const SV *)pmstash, PERL_MAGIC_symtab);
if (mg) {
PMOP **const array = (PMOP**) mg->mg_ptr;
U32 count = mg->mg_len / sizeof(PMOP**);
U32 i = count;
while (i--) {
if (array[i] == o) {
/* Found it. Move the entry at the end to overwrite it. */
array[i] = array[--count];
mg->mg_len = count * sizeof(PMOP**);
/* Could realloc smaller at this point always, but probably
not worth it. Probably worth free()ing if we're the
last. */
if(!count) {
Safefree(mg->mg_ptr);
mg->mg_ptr = NULL;
}
break;
}
}
}
}
if (PL_curpm == o)
PL_curpm = NULL;
#ifdef USE_ITHREADS
if (flags)
PmopSTASH_free(o);
#endif
}
STATIC void
S_find_and_forget_pmops(pTHX_ OP *o)
{
PERL_ARGS_ASSERT_FIND_AND_FORGET_PMOPS;
if (o->op_flags & OPf_KIDS) {
OP *kid = cUNOPo->op_first;
while (kid) {
switch (kid->op_type) {
case OP_SUBST:
case OP_PUSHRE:
case OP_MATCH:
case OP_QR:
forget_pmop((PMOP*)kid, 0);
}
find_and_forget_pmops(kid);
kid = kid->op_sibling;
}
}
}
void
Perl_op_null(pTHX_ OP *o)
{
dVAR;
PERL_ARGS_ASSERT_OP_NULL;
if (o->op_type == OP_NULL)
return;
if (!PL_madskills)
op_clear(o);
o->op_targ = o->op_type;
o->op_type = OP_NULL;
o->op_ppaddr = PL_ppaddr[OP_NULL];
}
void
Perl_op_refcnt_lock(pTHX)
{
dVAR;
PERL_UNUSED_CONTEXT;
OP_REFCNT_LOCK;
}
void
Perl_op_refcnt_unlock(pTHX)
{
dVAR;
PERL_UNUSED_CONTEXT;
OP_REFCNT_UNLOCK;
}
/* Contextualizers */
#define LINKLIST(o) ((o)->op_next ? (o)->op_next : linklist((OP*)o))
static OP *
S_linklist(pTHX_ OP *o)
{
OP *first;
PERL_ARGS_ASSERT_LINKLIST;
if (o->op_next)
return o->op_next;
/* establish postfix order */
first = cUNOPo->op_first;
if (first) {
register OP *kid;
o->op_next = LINKLIST(first);
kid = first;
for (;;) {
if (kid->op_sibling) {
kid->op_next = LINKLIST(kid->op_sibling);
kid = kid->op_sibling;
} else {
kid->op_next = o;
break;
}
}
}
else
o->op_next = o;
return o->op_next;
}
static OP *
S_scalarkids(pTHX_ OP *o)
{
if (o && o->op_flags & OPf_KIDS) {
OP *kid;
for (kid = cLISTOPo->op_first; kid; kid = kid->op_sibling)
scalar(kid);
}
return o;
}
STATIC OP *
S_scalarboolean(pTHX_ OP *o)
{
dVAR;
PERL_ARGS_ASSERT_SCALARBOOLEAN;
if (o->op_type == OP_SASSIGN && cBINOPo->op_first->op_type == OP_CONST) {
if (ckWARN(WARN_SYNTAX)) {
const line_t oldline = CopLINE(PL_curcop);
if (PL_parser && PL_parser->copline != NOLINE)
CopLINE_set(PL_curcop, PL_parser->copline);
Perl_warner(aTHX_ packWARN(WARN_SYNTAX), "Found = in conditional, should be ==");
CopLINE_set(PL_curcop, oldline);
}
}
return scalar(o);
}
OP *
Perl_scalar(pTHX_ OP *o)
{
dVAR;
OP *kid;
/* assumes no premature commitment */
if (!o || (PL_parser && PL_parser->error_count)
|| (o->op_flags & OPf_WANT)
|| o->op_type == OP_RETURN)
{
return o;
}
o->op_flags = (o->op_flags & ~OPf_WANT) | OPf_WANT_SCALAR;
switch (o->op_type) {
case OP_REPEAT:
scalar(cBINOPo->op_first);
break;
case OP_OR:
case OP_AND:
case OP_COND_EXPR:
for (kid = cUNOPo->op_first->op_sibling; kid; kid = kid->op_sibling)
scalar(kid);
break;
/* FALL THROUGH */
case OP_SPLIT:
case OP_MATCH:
case OP_QR:
case OP_SUBST:
case OP_NULL:
default:
if (o->op_flags & OPf_KIDS) {
for (kid = cUNOPo->op_first; kid; kid = kid->op_sibling)
scalar(kid);
}
break;
case OP_LEAVE:
case OP_LEAVETRY:
kid = cLISTOPo->op_first;
scalar(kid);
while ((kid = kid->op_sibling)) {
if (kid->op_sibling)
scalarvoid(kid);
else
scalar(kid);
}
PL_curcop = &PL_compiling;
break;
case OP_SCOPE:
case OP_LINESEQ:
case OP_LIST:
for (kid = cLISTOPo->op_first; kid; kid = kid->op_sibling) {
if (kid->op_sibling)
scalarvoid(kid);
else
scalar(kid);
}
PL_curcop = &PL_compiling;
break;
case OP_SORT:
Perl_ck_warner(aTHX_ packWARN(WARN_VOID), "Useless use of sort in scalar context");
break;
}
return o;
}
OP *
Perl_scalarvoid(pTHX_ OP *o)
{
dVAR;
OP *kid;
const char* useless = NULL;
SV* sv;
U8 want;
PERL_ARGS_ASSERT_SCALARVOID;
/* trailing mad null ops don't count as "there" for void processing */
if (PL_madskills &&
o->op_type != OP_NULL &&
o->op_sibling &&
o->op_sibling->op_type == OP_NULL)
{
OP *sib;
for (sib = o->op_sibling;
sib && sib->op_type == OP_NULL;
sib = sib->op_sibling) ;
if (!sib)
return o;
}
if (o->op_type == OP_NEXTSTATE
|| o->op_type == OP_DBSTATE
|| (o->op_type == OP_NULL && (o->op_targ == OP_NEXTSTATE
|| o->op_targ == OP_DBSTATE)))
PL_curcop = (COP*)o; /* for warning below */
/* assumes no premature commitment */
want = o->op_flags & OPf_WANT;
if ((want && want != OPf_WANT_SCALAR)
|| (PL_parser && PL_parser->error_count)
|| o->op_type == OP_RETURN || o->op_type == OP_REQUIRE)
{
return o;
}
if ((o->op_private & OPpTARGET_MY)
&& (PL_opargs[o->op_type] & OA_TARGLEX))/* OPp share the meaning */
{
return scalar(o); /* As if inside SASSIGN */
}
o->op_flags = (o->op_flags & ~OPf_WANT) | OPf_WANT_VOID;