pp.c

/*    pp.c
 *
 *    Copyright (c) 1991-1997, Larry Wall
 *
 *    You may distribute under the terms of either the GNU General Public
 *    License or the Artistic License, as specified in the README file.
 *
 */

/*
 * "It's a big house this, and very peculiar.  Always a bit more to discover,
 * and no knowing what you'll find around a corner.  And Elves, sir!" --Samwise
 */

#include "EXTERN.h"
#include "perl.h"

/*
 * The compiler on Concurrent CX/UX systems has a subtle bug which only
 * seems to show up when compiling pp.c - it generates the wrong double
 * precision constant value for (double)UV_MAX when used inline in the body
 * of the code below, so this makes a static variable up front (which the
 * compiler seems to get correct) and uses it in place of UV_MAX below.
 */
#ifdef CXUX_BROKEN_CONSTANT_CONVERT
static double UV_MAX_cxux = ((double)UV_MAX);
#endif

/*
 * Types used in bitwise operations.
 *
 * Normally we'd just use IV and UV.  However, some hardware and
 * software combinations (e.g. Alpha and current OSF/1) don't have a
 * floating-point type to use for NV that has adequate bits to fully
 * hold an IV/UV.  (In other words, sizeof(long) == sizeof(double).)
 *
 * It just so happens that "int" is the right size almost everywhere.
 */
typedef int IBW;
typedef unsigned UBW;

/*
 * Mask used after bitwise operations.
 *
 * There is at least one realm (Cray word machines) that doesn't
 * have an integral type (except char) small enough to be represented
 * in a double without loss; that is, it has no 32-bit type.
 */
#if LONGSIZE > 4  && defined(_CRAY) && !defined(_CRAYMPP)
#  define BW_BITS  32
#  define BW_MASK  ((1 << BW_BITS) - 1)
#  define BW_SIGN  (1 << (BW_BITS - 1))
#  define BWi(i)  (((i) & BW_SIGN) ? ((i) | ~BW_MASK) : ((i) & BW_MASK))
#  define BWu(u)  ((u) & BW_MASK)
#else
#  define BWi(i)  (i)
#  define BWu(u)  (u)
#endif

/*
 * Offset for integer pack/unpack.
 *
 * On architectures where I16 and I32 aren't really 16 and 32 bits,
 * which for now are all Crays, pack and unpack have to play games.
 */

/*
 * These values are required for portability of pack() output.
 * If they're not right on your machine, then pack() and unpack()
 * wouldn't work right anyway; you'll need to apply the Cray hack.
 * (I'd like to check them with #if, but you can't use sizeof() in
 * the preprocessor.)  --???
 */
/*
    The appropriate SHORTSIZE, INTSIZE, LONGSIZE, and LONGLONGSIZE
    defines are now in config.h.  --Andy Dougherty  April 1998
 */
#define SIZE16 2
#define SIZE32 4

#if BYTEORDER > 0xFFFF && defined(_CRAY) && !defined(_CRAYMPP)
#  if BYTEORDER == 0x12345678
#    define OFF16(p)	(char*)(p)
#    define OFF32(p)	(char*)(p)
#  else
#    if BYTEORDER == 0x87654321
#      define OFF16(p)	((char*)(p) + (sizeof(U16) - SIZE16))
#      define OFF32(p)	((char*)(p) + (sizeof(U32) - SIZE32))
#    else
       }}}} bad cray byte order
#    endif
#  endif
#  define COPY16(s,p)  (*(p) = 0, Copy(s, OFF16(p), SIZE16, char))
#  define COPY32(s,p)  (*(p) = 0, Copy(s, OFF32(p), SIZE32, char))
#  define CAT16(sv,p)  sv_catpvn(sv, OFF16(p), SIZE16)
#  define CAT32(sv,p)  sv_catpvn(sv, OFF32(p), SIZE32)
#else
#  define COPY16(s,p)  Copy(s, p, SIZE16, char)
#  define COPY32(s,p)  Copy(s, p, SIZE32, char)
#  define CAT16(sv,p)  sv_catpvn(sv, (char*)(p), SIZE16)
#  define CAT32(sv,p)  sv_catpvn(sv, (char*)(p), SIZE32)
#endif

#ifndef PERL_OBJECT
static void doencodes _((SV* sv, char* s, I32 len));
static SV* refto _((SV* sv));
static U32 seed _((void));
#endif

static bool srand_called = FALSE;

/* variations on pp_null */

#ifdef I_UNISTD
#include <unistd.h>
#endif

/* XXX I can't imagine anyone who doesn't have this actually _needs_
   it, since pid_t is an integral type.
   --AD  2/20/1998
*/
#ifdef NEED_GETPID_PROTO
extern Pid_t getpid (void);
#endif

PP(pp_stub)
{
    djSP;
    if (GIMME_V == G_SCALAR)
	XPUSHs(&PL_sv_undef);
    RETURN;
}

PP(pp_scalar)
{
    return NORMAL;
}

/* Pushy stuff. */

PP(pp_padav)
{
    djSP; dTARGET;
    if (PL_op->op_private & OPpLVAL_INTRO)
	SAVECLEARSV(PL_curpad[PL_op->op_targ]);
    EXTEND(SP, 1);
    if (PL_op->op_flags & OPf_REF) {
	PUSHs(TARG);
	RETURN;
    }
    if (GIMME == G_ARRAY) {
	I32 maxarg = AvFILL((AV*)TARG) + 1;
	EXTEND(SP, maxarg);
	if (SvMAGICAL(TARG)) {
	    U32 i;
	    for (i=0; i < maxarg; i++) {
		SV **svp = av_fetch((AV*)TARG, i, FALSE);
		SP[i+1] = (svp) ? *svp : &PL_sv_undef;
	    }
	}
	else {
	    Copy(AvARRAY((AV*)TARG), SP+1, maxarg, SV*);
	}
	SP += maxarg;
    }
    else {
	SV* sv = sv_newmortal();
	I32 maxarg = AvFILL((AV*)TARG) + 1;
	sv_setiv(sv, maxarg);
	PUSHs(sv);
    }
    RETURN;
}

PP(pp_padhv)
{
    djSP; dTARGET;
    I32 gimme;

    XPUSHs(TARG);
    if (PL_op->op_private & OPpLVAL_INTRO)
	SAVECLEARSV(PL_curpad[PL_op->op_targ]);
    if (PL_op->op_flags & OPf_REF)
	RETURN;
    gimme = GIMME_V;
    if (gimme == G_ARRAY) {
	RETURNOP(do_kv(ARGS));
    }
    else if (gimme == G_SCALAR) {
	SV* sv = sv_newmortal();
	if (HvFILL((HV*)TARG))
	    sv_setpvf(sv, "%ld/%ld",
		      (long)HvFILL((HV*)TARG), (long)HvMAX((HV*)TARG) + 1);
	else
	    sv_setiv(sv, 0);
	SETs(sv);
    }
    RETURN;
}

PP(pp_padany)
{
    DIE("NOT IMPL LINE %d",__LINE__);
}

/* Translations. */

PP(pp_rv2gv)
{
    djSP; dTOPss;

    if (SvROK(sv)) {
      wasref:
	sv = SvRV(sv);
	if (SvTYPE(sv) == SVt_PVIO) {
	    GV *gv = (GV*) sv_newmortal();
	    gv_init(gv, 0, "", 0, 0);
	    GvIOp(gv) = (IO *)sv;
	    (void)SvREFCNT_inc(sv);
	    sv = (SV*) gv;
	} else if (SvTYPE(sv) != SVt_PVGV)
	    DIE("Not a GLOB reference");
    }
    else {
	if (SvTYPE(sv) != SVt_PVGV) {
	    char *sym;

	    if (SvGMAGICAL(sv)) {
		mg_get(sv);
		if (SvROK(sv))
		    goto wasref;
	    }
	    if (!SvOK(sv)) {
		if (PL_op->op_flags & OPf_REF ||
		    PL_op->op_private & HINT_STRICT_REFS)
		    DIE(no_usym, "a symbol");
		if (PL_dowarn)
		    warn(warn_uninit);
		RETSETUNDEF;
	    }
	    sym = SvPV(sv, PL_na);
	    if (PL_op->op_private & HINT_STRICT_REFS)
		DIE(no_symref, sym, "a symbol");
	    sv = (SV*)gv_fetchpv(sym, TRUE, SVt_PVGV);
	}
    }
    if (PL_op->op_private & OPpLVAL_INTRO)
	save_gp((GV*)sv, !(PL_op->op_flags & OPf_SPECIAL));
    SETs(sv);
    RETURN;
}

PP(pp_rv2sv)
{
    djSP; dTOPss;

    if (SvROK(sv)) {
      wasref:
	sv = SvRV(sv);
	switch (SvTYPE(sv)) {
	case SVt_PVAV:
	case SVt_PVHV:
	case SVt_PVCV:
	    DIE("Not a SCALAR reference");
	}
    }
    else {
	GV *gv = (GV*)sv;
	char *sym;

	if (SvTYPE(gv) != SVt_PVGV) {
	    if (SvGMAGICAL(sv)) {
		mg_get(sv);
		if (SvROK(sv))
		    goto wasref;
	    }
	    if (!SvOK(sv)) {
		if (PL_op->op_flags & OPf_REF ||
		    PL_op->op_private & HINT_STRICT_REFS)
		    DIE(no_usym, "a SCALAR");
		if (PL_dowarn)
		    warn(warn_uninit);
		RETSETUNDEF;
	    }
	    sym = SvPV(sv, PL_na);
	    if (PL_op->op_private & HINT_STRICT_REFS)
		DIE(no_symref, sym, "a SCALAR");
	    gv = (GV*)gv_fetchpv(sym, TRUE, SVt_PV);
	}
	sv = GvSV(gv);
    }
    if (PL_op->op_flags & OPf_MOD) {
	if (PL_op->op_private & OPpLVAL_INTRO)
	    sv = save_scalar((GV*)TOPs);
	else if (PL_op->op_private & OPpDEREF)
	    vivify_ref(sv, PL_op->op_private & OPpDEREF);
    }
    SETs(sv);
    RETURN;
}

PP(pp_av2arylen)
{
    djSP;
    AV *av = (AV*)TOPs;
    SV *sv = AvARYLEN(av);
    if (!sv) {
	AvARYLEN(av) = sv = NEWSV(0,0);
	sv_upgrade(sv, SVt_IV);
	sv_magic(sv, (SV*)av, '#', Nullch, 0);
    }
    SETs(sv);
    RETURN;
}

PP(pp_pos)
{
    djSP; dTARGET; dPOPss;

    if (PL_op->op_flags & OPf_MOD) {
	if (SvTYPE(TARG) < SVt_PVLV) {
	    sv_upgrade(TARG, SVt_PVLV);
	    sv_magic(TARG, Nullsv, '.', Nullch, 0);
	}

	LvTYPE(TARG) = '.';
	if (LvTARG(TARG) != sv) {
	    if (LvTARG(TARG))
		SvREFCNT_dec(LvTARG(TARG));
	    LvTARG(TARG) = SvREFCNT_inc(sv);
	}
	PUSHs(TARG);	/* no SvSETMAGIC */
	RETURN;
    }
    else {
	MAGIC* mg;

	if (SvTYPE(sv) >= SVt_PVMG && SvMAGIC(sv)) {
	    mg = mg_find(sv, 'g');
	    if (mg && mg->mg_len >= 0) {
		PUSHi(mg->mg_len + PL_curcop->cop_arybase);
		RETURN;
	    }
	}
	RETPUSHUNDEF;
    }
}

PP(pp_rv2cv)
{
    djSP;
    GV *gv;
    HV *stash;

    /* We usually try to add a non-existent subroutine in case of AUTOLOAD. */
    /* (But not in defined().) */
    CV *cv = sv_2cv(TOPs, &stash, &gv, !(PL_op->op_flags & OPf_SPECIAL));
    if (cv) {
	if (CvCLONE(cv))
	    cv = (CV*)sv_2mortal((SV*)cv_clone(cv));
    }
    else
	cv = (CV*)&PL_sv_undef;
    SETs((SV*)cv);
    RETURN;
}

PP(pp_prototype)
{
    djSP;
    CV *cv;
    HV *stash;
    GV *gv;
    SV *ret;

    ret = &PL_sv_undef;
    if (SvPOK(TOPs) && SvCUR(TOPs) >= 7) {
	char *s = SvPVX(TOPs);
	if (strnEQ(s, "CORE::", 6)) {
	    int code;
	    
	    code = keyword(s + 6, SvCUR(TOPs) - 6);
	    if (code < 0) {	/* Overridable. */
#define MAX_ARGS_OP ((sizeof(I32) - 1) * 2)
		int i = 0, n = 0, seen_question = 0;
		I32 oa;
		char str[ MAX_ARGS_OP * 2 + 2 ]; /* One ';', one '\0' */

		while (i < MAXO) {	/* The slow way. */
		    if (strEQ(s + 6, op_name[i]) || strEQ(s + 6, op_desc[i]))
			goto found;
		    i++;
		}
		goto nonesuch;		/* Should not happen... */
	      found:
		oa = opargs[i] >> OASHIFT;
		while (oa) {
		    if (oa & OA_OPTIONAL) {
			seen_question = 1;
			str[n++] = ';';
		    } else if (seen_question) 
			goto set;	/* XXXX system, exec */
		    if ((oa & (OA_OPTIONAL - 1)) >= OA_AVREF 
			&& (oa & (OA_OPTIONAL - 1)) <= OA_HVREF) {
			str[n++] = '\\';
		    }
		    /* What to do with R ((un)tie, tied, (sys)read, recv)? */
		    str[n++] = ("?$@@%&*$")[oa & (OA_OPTIONAL - 1)];
		    oa = oa >> 4;
		}
		str[n++] = '\0';
		ret = sv_2mortal(newSVpv(str, n - 1));
	    } else if (code)		/* Non-Overridable */
		goto set;
	    else {			/* None such */
	      nonesuch:
		croak("Cannot find an opnumber for \"%s\"", s+6);
	    }
	}
    }
    cv = sv_2cv(TOPs, &stash, &gv, FALSE);
    if (cv && SvPOK(cv))
	ret = sv_2mortal(newSVpv(SvPVX(cv), SvCUR(cv)));
  set:
    SETs(ret);
    RETURN;
}

PP(pp_anoncode)
{
    djSP;
    CV* cv = (CV*)PL_curpad[PL_op->op_targ];
    if (CvCLONE(cv))
	cv = (CV*)sv_2mortal((SV*)cv_clone(cv));
    EXTEND(SP,1);
    PUSHs((SV*)cv);
    RETURN;
}

PP(pp_srefgen)
{
    djSP;
    *SP = refto(*SP);
    RETURN;
}

PP(pp_refgen)
{
    djSP; dMARK;
    if (GIMME != G_ARRAY) {
	if (++MARK <= SP)
	    *MARK = *SP;
	else
	    *MARK = &PL_sv_undef;
	*MARK = refto(*MARK);
	SP = MARK;
	RETURN;
    }
    EXTEND_MORTAL(SP - MARK);
    while (++MARK <= SP)
	*MARK = refto(*MARK);
    RETURN;
}

STATIC SV*
refto(SV *sv)
{
    SV* rv;

    if (SvTYPE(sv) == SVt_PVLV && LvTYPE(sv) == 'y') {
	if (LvTARGLEN(sv))
	    vivify_defelem(sv);
	if (!(sv = LvTARG(sv)))
	    sv = &PL_sv_undef;
    }
    else if (SvPADTMP(sv))
	sv = newSVsv(sv);
    else {
	SvTEMP_off(sv);
	(void)SvREFCNT_inc(sv);
    }
    rv = sv_newmortal();
    sv_upgrade(rv, SVt_RV);
    SvRV(rv) = sv;
    SvROK_on(rv);
    return rv;
}

PP(pp_ref)
{
    djSP; dTARGET;
    SV *sv;
    char *pv;

    sv = POPs;

    if (sv && SvGMAGICAL(sv))
	mg_get(sv);

    if (!sv || !SvROK(sv))
	RETPUSHNO;

    sv = SvRV(sv);
    pv = sv_reftype(sv,TRUE);
    PUSHp(pv, strlen(pv));
    RETURN;
}

PP(pp_bless)
{
    djSP;
    HV *stash;

    if (MAXARG == 1)
	stash = PL_curcop->cop_stash;
    else {
	SV *ssv = POPs;
	STRLEN len;
	char *ptr = SvPV(ssv,len);
	if (PL_dowarn && len == 0)
	    warn("Explicit blessing to '' (assuming package main)");
	stash = gv_stashpvn(ptr, len, TRUE);
    }

    (void)sv_bless(TOPs, stash);
    RETURN;
}

PP(pp_gelem)
{
    GV *gv;
    SV *sv;
    SV *tmpRef;
    char *elem;
    djSP;

    sv = POPs;
    elem = SvPV(sv, PL_na);
    gv = (GV*)POPs;
    tmpRef = Nullsv;
    sv = Nullsv;
    switch (elem ? *elem : '\0')
    {
    case 'A':
	if (strEQ(elem, "ARRAY"))
	    tmpRef = (SV*)GvAV(gv);
	break;
    case 'C':
	if (strEQ(elem, "CODE"))
	    tmpRef = (SV*)GvCVu(gv);
	break;
    case 'F':
	if (strEQ(elem, "FILEHANDLE")) /* XXX deprecate in 5.005 */
	    tmpRef = (SV*)GvIOp(gv);
	break;
    case 'G':
	if (strEQ(elem, "GLOB"))
	    tmpRef = (SV*)gv;
	break;
    case 'H':
	if (strEQ(elem, "HASH"))
	    tmpRef = (SV*)GvHV(gv);
	break;
    case 'I':
	if (strEQ(elem, "IO"))
	    tmpRef = (SV*)GvIOp(gv);
	break;
    case 'N':
	if (strEQ(elem, "NAME"))
	    sv = newSVpv(GvNAME(gv), GvNAMELEN(gv));
	break;
    case 'P':
	if (strEQ(elem, "PACKAGE"))
	    sv = newSVpv(HvNAME(GvSTASH(gv)), 0);
	break;
    case 'S':
	if (strEQ(elem, "SCALAR"))
	    tmpRef = GvSV(gv);
	break;
    }
    if (tmpRef)
	sv = newRV(tmpRef);
    if (sv)
	sv_2mortal(sv);
    else
	sv = &PL_sv_undef;
    XPUSHs(sv);
    RETURN;
}

/* Pattern matching */

PP(pp_study)
{
    djSP; dPOPss;
    register UNOP *unop = cUNOP;
    register unsigned char *s;
    register I32 pos;
    register I32 ch;
    register I32 *sfirst;
    register I32 *snext;
    STRLEN len;

    if (sv == PL_lastscream) {
	if (SvSCREAM(sv))
	    RETPUSHYES;
    }
    else {
	if (PL_lastscream) {
	    SvSCREAM_off(PL_lastscream);
	    SvREFCNT_dec(PL_lastscream);
	}
	PL_lastscream = SvREFCNT_inc(sv);
    }

    s = (unsigned char*)(SvPV(sv, len));
    pos = len;
    if (pos <= 0)
	RETPUSHNO;
    if (pos > PL_maxscream) {
	if (PL_maxscream < 0) {
	    PL_maxscream = pos + 80;
	    New(301, PL_screamfirst, 256, I32);
	    New(302, PL_screamnext, PL_maxscream, I32);
	}
	else {
	    PL_maxscream = pos + pos / 4;
	    Renew(PL_screamnext, PL_maxscream, I32);
	}
    }

    sfirst = PL_screamfirst;
    snext = PL_screamnext;

    if (!sfirst || !snext)
	DIE("do_study: out of memory");

    for (ch = 256; ch; --ch)
	*sfirst++ = -1;
    sfirst -= 256;

    while (--pos >= 0) {
	ch = s[pos];
	if (sfirst[ch] >= 0)
	    snext[pos] = sfirst[ch] - pos;
	else
	    snext[pos] = -pos;
	sfirst[ch] = pos;
    }

    SvSCREAM_on(sv);
    sv_magic(sv, Nullsv, 'g', Nullch, 0);	/* piggyback on m//g magic */
    RETPUSHYES;
}

PP(pp_trans)
{
    djSP; dTARG;
    SV *sv;

    if (PL_op->op_flags & OPf_STACKED)
	sv = POPs;
    else {
	sv = DEFSV;
	EXTEND(SP,1);
    }
    TARG = sv_newmortal();
    PUSHi(do_trans(sv, PL_op));
    RETURN;
}

/* Lvalue operators. */

PP(pp_schop)
{
    djSP; dTARGET;
    do_chop(TARG, TOPs);
    SETTARG;
    RETURN;
}

PP(pp_chop)
{
    djSP; dMARK; dTARGET;
    while (SP > MARK)
	do_chop(TARG, POPs);
    PUSHTARG;
    RETURN;
}

PP(pp_schomp)
{
    djSP; dTARGET;
    SETi(do_chomp(TOPs));
    RETURN;
}

PP(pp_chomp)
{
    djSP; dMARK; dTARGET;
    register I32 count = 0;

    while (SP > MARK)
	count += do_chomp(POPs);
    PUSHi(count);
    RETURN;
}

PP(pp_defined)
{
    djSP;
    register SV* sv;

    sv = POPs;
    if (!sv || !SvANY(sv))
	RETPUSHNO;
    switch (SvTYPE(sv)) {
    case SVt_PVAV:
	if (AvMAX(sv) >= 0 || SvGMAGICAL(sv))
	    RETPUSHYES;
	break;
    case SVt_PVHV:
	if (HvARRAY(sv) || SvGMAGICAL(sv))
	    RETPUSHYES;
	break;
    case SVt_PVCV:
	if (CvROOT(sv) || CvXSUB(sv))
	    RETPUSHYES;
	break;
    default:
	if (SvGMAGICAL(sv))
	    mg_get(sv);
	if (SvOK(sv))
	    RETPUSHYES;
    }
    RETPUSHNO;
}

PP(pp_undef)
{
    djSP;
    SV *sv;

    if (!PL_op->op_private) {
	EXTEND(SP, 1);
	RETPUSHUNDEF;
    }

    sv = POPs;
    if (!sv)
	RETPUSHUNDEF;

    if (SvTHINKFIRST(sv)) {
	if (SvREADONLY(sv))
	    RETPUSHUNDEF;
	if (SvROK(sv))
	    sv_unref(sv);
    }

    switch (SvTYPE(sv)) {
    case SVt_NULL:
	break;
    case SVt_PVAV:
	av_undef((AV*)sv);
	break;
    case SVt_PVHV:
	hv_undef((HV*)sv);
	break;
    case SVt_PVCV:
	if (PL_dowarn && cv_const_sv((CV*)sv))
	    warn("Constant subroutine %s undefined",
		 CvANON((CV*)sv) ? "(anonymous)" : GvENAME(CvGV((CV*)sv)));
	/* FALL THROUGH */
    case SVt_PVFM:
	{ GV* gv = (GV*)SvREFCNT_inc(CvGV((CV*)sv));
	  cv_undef((CV*)sv);
	  CvGV((CV*)sv) = gv; }   /* let user-undef'd sub keep its identity */
	break;
    case SVt_PVGV:
	if (SvFAKE(sv))
	    SvSetMagicSV(sv, &PL_sv_undef);
	else {
	    GP *gp;
	    gp_free((GV*)sv);
	    Newz(602, gp, 1, GP);
	    GvGP(sv) = gp_ref(gp);
	    GvSV(sv) = NEWSV(72,0);
	    GvLINE(sv) = PL_curcop->cop_line;
	    GvEGV(sv) = (GV*)sv;
	    GvMULTI_on(sv);
	}
	break;
    default:
	if (SvTYPE(sv) >= SVt_PV && SvPVX(sv) && SvLEN(sv)) {
	    (void)SvOOK_off(sv);
	    Safefree(SvPVX(sv));
	    SvPV_set(sv, Nullch);
	    SvLEN_set(sv, 0);
	}
	(void)SvOK_off(sv);
	SvSETMAGIC(sv);
    }

    RETPUSHUNDEF;
}

PP(pp_predec)
{
    djSP;
    if (SvREADONLY(TOPs) || SvTYPE(TOPs) > SVt_PVLV)
	croak(no_modify);
    if (SvIOK(TOPs) && !SvNOK(TOPs) && !SvPOK(TOPs) &&
    	SvIVX(TOPs) != IV_MIN)
    {
	--SvIVX(TOPs);
	SvFLAGS(TOPs) &= ~(SVp_NOK|SVp_POK);
    }
    else
	sv_dec(TOPs);
    SvSETMAGIC(TOPs);
    return NORMAL;
}

PP(pp_postinc)
{
    djSP; dTARGET;
    if (SvREADONLY(TOPs) || SvTYPE(TOPs) > SVt_PVLV)
	croak(no_modify);
    sv_setsv(TARG, TOPs);
    if (SvIOK(TOPs) && !SvNOK(TOPs) && !SvPOK(TOPs) &&
    	SvIVX(TOPs) != IV_MAX)
    {
	++SvIVX(TOPs);
	SvFLAGS(TOPs) &= ~(SVp_NOK|SVp_POK);
    }
    else
	sv_inc(TOPs);
    SvSETMAGIC(TOPs);
    if (!SvOK(TARG))
	sv_setiv(TARG, 0);
    SETs(TARG);
    return NORMAL;
}

PP(pp_postdec)
{
    djSP; dTARGET;
    if(SvREADONLY(TOPs) || SvTYPE(TOPs) > SVt_PVLV)
	croak(no_modify);
    sv_setsv(TARG, TOPs);
    if (SvIOK(TOPs) && !SvNOK(TOPs) && !SvPOK(TOPs) &&
    	SvIVX(TOPs) != IV_MIN)
    {
	--SvIVX(TOPs);
	SvFLAGS(TOPs) &= ~(SVp_NOK|SVp_POK);
    }
    else
	sv_dec(TOPs);
    SvSETMAGIC(TOPs);
    SETs(TARG);
    return NORMAL;
}

/* Ordinary operators. */

PP(pp_pow)
{
    djSP; dATARGET; tryAMAGICbin(pow,opASSIGN);
    {
      dPOPTOPnnrl;
      SETn( pow( left, right) );
      RETURN;
    }
}

PP(pp_multiply)
{
    djSP; dATARGET; tryAMAGICbin(mult,opASSIGN);
    {
      dPOPTOPnnrl;
      SETn( left * right );
      RETURN;
    }
}

PP(pp_divide)
{
    djSP; dATARGET; tryAMAGICbin(div,opASSIGN);
    {
      dPOPPOPnnrl;
      double value;
      if (right == 0.0)
	DIE("Illegal division by zero");
#ifdef SLOPPYDIVIDE
      /* insure that 20./5. == 4. */
      {
	IV k;
	if ((double)I_V(left)  == left &&
	    (double)I_V(right) == right &&
	    (k = I_V(left)/I_V(right))*I_V(right) == I_V(left)) {
	    value = k;
	} else {
	    value = left / right;
	}
      }
#else
      value = left / right;
#endif
      PUSHn( value );
      RETURN;
    }
}

PP(pp_modulo)
{
    djSP; dATARGET; tryAMAGICbin(modulo,opASSIGN);
    {
      UV left;
      UV right;
      bool left_neg;
      bool right_neg;
      UV ans;

      if (SvIOK(TOPs) && !SvNOK(TOPs) && !SvPOK(TOPs)) {
	IV i = SvIVX(POPs);
	right = (right_neg = (i < 0)) ? -i : i;
      }
      else {
	double n = POPn;
	right = U_V((right_neg = (n < 0)) ? -n : n);
      }

      if (SvIOK(TOPs) && !SvNOK(TOPs) && !SvPOK(TOPs)) {
	IV i = SvIVX(POPs);
	left = (left_neg = (i < 0)) ? -i : i;
      }
      else {
	double n = POPn;
	left = U_V((left_neg = (n < 0)) ? -n : n);
      }

      if (!right)
	DIE("Illegal modulus zero");

      ans = left % right;
      if ((left_neg != right_neg) && ans)
	ans = right - ans;
      if (right_neg) {
	/* XXX may warn: unary minus operator applied to unsigned type */
	/* could change -foo to be (~foo)+1 instead	*/
	if (ans <= ~((UV)IV_MAX)+1)
	  sv_setiv(TARG, ~ans+1);
	else
	  sv_setnv(TARG, -(double)ans);
      }
      else
	sv_setuv(TARG, ans);
      PUSHTARG;
      RETURN;
    }
}

PP(pp_repeat)
{
  djSP; dATARGET; tryAMAGICbin(repeat,opASSIGN);
  {
    register I32 count = POPi;
    if (GIMME == G_ARRAY && PL_op->op_private & OPpREPEAT_DOLIST) {
	dMARK;
	I32 items = SP - MARK;
	I32 max;

	max = items * count;
	MEXTEND(MARK, max);
	if (count > 1) {
	    while (SP > MARK) {
		if (*SP)
		    SvTEMP_off((*SP));
		SP--;
	    }
	    MARK++;
	    repeatcpy((char*)(MARK + items), (char*)MARK,
		items * sizeof(SV*), count - 1);
	    SP += max;
	}
	else if (count <= 0)
	    SP -= items;
    }
    else {	/* Note: mark already snarfed by pp_list */
	SV *tmpstr;
	STRLEN len;

	tmpstr = POPs;
	if (TARG == tmpstr && SvTHINKFIRST(tmpstr)) {
	    if (SvREADONLY(tmpstr) && PL_curcop != &PL_compiling)
		DIE("Can't x= to readonly value");
	    if (SvROK(tmpstr))
		sv_unref(tmpstr);
	}
	SvSetSV(TARG, tmpstr);
	SvPV_force(TARG, len);
	if (count != 1) {
	    if (count < 1)
		SvCUR_set(TARG, 0);
	    else {
		SvGROW(TARG, (count * len) + 1);
		repeatcpy(SvPVX(TARG) + len, SvPVX(TARG), len, count - 1);
		SvCUR(TARG) *= count;
	    }
	    *SvEND(TARG) = '\0';
	}
	(void)SvPOK_only(TARG);
	PUSHTARG;
    }
    RETURN;
  }
}

PP(pp_subtract)
{
    djSP; dATARGET; tryAMAGICbin(subtr,opASSIGN);
    {
      dPOPTOPnnrl_ul;
      SETn( left - right );
      RETURN;
    }
}

PP(pp_left_shift)
{
    djSP; dATARGET; tryAMAGICbin(lshift,opASSIGN);
    {
      IBW shift = POPi;
      if (PL_op->op_private & HINT_INTEGER) {
	IBW i = TOPi;
	i = BWi(i) << shift;
	SETi(BWi(i));
      }
      else {
	UBW u = TOPu;
	u <<= shift;
	SETu(BWu(u));
      }
      RETURN;
    }
}

PP(pp_right_shift)
{
    djSP; dATARGET; tryAMAGICbin(rshift,opASSIGN);
    {
      IBW shift = POPi;
      if (PL_op->op_private & HINT_INTEGER) {
	IBW i = TOPi;
	i = BWi(i) >> shift;
	SETi(BWi(i));
      }
      else {
	UBW u = TOPu;
	u >>= shift;
	SETu(BWu(u));
      }
      RETURN;
    }
}

PP(pp_lt)
{
    djSP; tryAMAGICbinSET(lt,0);
    {
      dPOPnv;
      SETs(boolSV(TOPn < value));
      RETURN;
    }
}

PP(pp_gt)
{
    djSP; tryAMAGICbinSET(gt,0);
    {
      dPOPnv;
      SETs(boolSV(TOPn > value));
      RETURN;
    }
}

PP(pp_le)
{
    djSP; tryAMAGICbinSET(le,0);
    {
      dPOPnv;
      SETs(boolSV(TOPn <= value));
      RETURN;
    }
}

PP(pp_ge)
{
    djSP; tryAMAGICbinSET(ge,0);
    {
      dPOPnv;
      SETs(boolSV(TOPn >= value));
      RETURN;
    }
}

PP(pp_ne)
{
    djSP; tryAMAGICbinSET(ne,0);
    {
      dPOPnv;
      SETs(boolSV(TOPn != value));
      RETURN;
    }
}

PP(pp_ncmp)
{
    djSP; dTARGET; tryAMAGICbin(ncmp,0);
    {
      dPOPTOPnnrl;
      I32 value;

      if (left == right)
	value = 0;
      else if (left < right)
	value = -1;
      else if (left > right)
	value = 1;
      else {
	SETs(&PL_sv_undef);
	RETURN;
      }
      SETi(value);
      RETURN;
    }
}

PP(pp_slt)
{
    djSP; tryAMAGICbinSET(slt,0);
    {
      dPOPTOPssrl;
      int cmp = ((PL_op->op_private & OPpLOCALE)
		 ? sv_cmp_locale(left, right)
		 : sv_cmp(left, right));
      SETs(boolSV(cmp < 0));
      RETURN;
    }
}

PP(pp_sgt)
{
    djSP; tryAMAGICbinSET(sgt,0);
    {
      dPOPTOPssrl;
      int cmp = ((PL_op->op_private & OPpLOCALE)
		 ? sv_cmp_locale(left, right)
		 : sv_cmp(left, right));
      SETs(boolSV(cmp > 0));
      RETURN;
    }
}

PP(pp_sle)
{
    djSP; tryAMAGICbinSET(sle,0);
    {
      dPOPTOPssrl;
      int cmp = ((PL_op->op_private & OPpLOCALE)
		 ? sv_cmp_locale(left, right)
		 : sv_cmp(left, right));
      SETs(boolSV(cmp <= 0));
      RETURN;
    }
}

PP(pp_sge)
{
    djSP; tryAMAGICbinSET(sge,0);
    {
      dPOPTOPssrl;
      int cmp = ((PL_op->op_private & OPpLOCALE)
		 ? sv_cmp_locale(left, right)
		 : sv_cmp(left, right));
      SETs(boolSV(cmp >= 0));
      RETURN;
    }
}

PP(pp_seq)
{
    djSP; tryAMAGICbinSET(seq,0);
    {
      dPOPTOPssrl;
      SETs(boolSV(sv_eq(left, right)));
      RETURN;
    }
}

PP(pp_sne)
{
    djSP; tryAMAGICbinSET(sne,0);
    {
      dPOPTOPssrl;
      SETs(boolSV(!sv_eq(left, right)));
      RETURN;
    }
}

PP(pp_scmp)
{
    djSP; dTARGET;  tryAMAGICbin(scmp,0);
    {
      dPOPTOPssrl;
      int cmp = ((PL_op->op_private & OPpLOCALE)
		 ? sv_cmp_locale(left, right)
		 : sv_cmp(left, right));
      SETi( cmp );
      RETURN;
    }
}

PP(pp_bit_and)
{
    djSP; dATARGET; tryAMAGICbin(band,opASSIGN);
    {
      dPOPTOPssrl;
      if (SvNIOKp(left) || SvNIOKp(right)) {
	if (PL_op->op_private & HINT_INTEGER) {
	  IBW value = SvIV(left) & SvIV(right);
	  SETi(BWi(value));
	}
	else {
	  UBW value = SvUV(left) & SvUV(right);
	  SETu(BWu(value));
	}
      }
      else {
	do_vop(PL_op->op_type, TARG, left, right);
	SETTARG;
      }
      RETURN;
    }
}

PP(pp_bit_xor)
{
    djSP; dATARGET; tryAMAGICbin(bxor,opASSIGN);
    {
      dPOPTOPssrl;
      if (SvNIOKp(left) || SvNIOKp(right)) {
	if (PL_op->op_private & HINT_INTEGER) {
	  IBW value = (USE_LEFT(left) ? SvIV(left) : 0) ^ SvIV(right);
	  SETi(BWi(value));
	}
	else {
	  UBW value = (USE_LEFT(left) ? SvUV(left) : 0) ^ SvUV(right);
	  SETu(BWu(value));
	}
      }
      else {
	do_vop(PL_op->op_type, TARG, left, right);
	SETTARG;
      }
      RETURN;
    }
}

PP(pp_bit_or)
{
    djSP; dATARGET; tryAMAGICbin(bor,opASSIGN);
    {
      dPOPTOPssrl;
      if (SvNIOKp(left) || SvNIOKp(right)) {
	if (PL_op->op_private & HINT_INTEGER) {
	  IBW value = (USE_LEFT(left) ? SvIV(left) : 0) | SvIV(right);
	  SETi(BWi(value));
	}
	else {
	  UBW value = (USE_LEFT(left) ? SvUV(left) : 0) | SvUV(right);
	  SETu(BWu(value));
	}
      }
      else {
	do_vop(PL_op->op_type, TARG, left, right);
	SETTARG;
      }
      RETURN;
    }
}

PP(pp_negate)
{
    djSP; dTARGET; tryAMAGICun(neg);
    {
	dTOPss;
	if (SvGMAGICAL(sv))
	    mg_get(sv);
	if (SvIOKp(sv) && !SvNOKp(sv) && !SvPOKp(sv) && SvIVX(sv) != IV_MIN)
	    SETi(-SvIVX(sv));
	else if (SvNIOKp(sv))
	    SETn(-SvNV(sv));
	else if (SvPOKp(sv)) {
	    STRLEN len;
	    char *s = SvPV(sv, len);
	    if (isIDFIRST(*s)) {
		sv_setpvn(TARG, "-", 1);
		sv_catsv(TARG, sv);
	    }
	    else if (*s == '+' || *s == '-') {
		sv_setsv(TARG, sv);
		*SvPV_force(TARG, len) = *s == '-' ? '+' : '-';
	    }
	    else
		sv_setnv(TARG, -SvNV(sv));
	    SETTARG;
	}
	else
	    SETn(-SvNV(sv));
    }
    RETURN;
}

PP(pp_not)
{
#ifdef OVERLOAD
    djSP; tryAMAGICunSET(not);
#endif /* OVERLOAD */
    *PL_stack_sp = boolSV(!SvTRUE(*PL_stack_sp));
    return NORMAL;
}

PP(pp_complement)
{
    djSP; dTARGET; tryAMAGICun(compl);
    {
      dTOPss;
      if (SvNIOKp(sv)) {
	if (PL_op->op_private & HINT_INTEGER) {
	  IBW value = ~SvIV(sv);
	  SETi(BWi(value));
	}
	else {
	  UBW value = ~SvUV(sv);
	  SETu(BWu(value));
	}
      }
      else {
	register char *tmps;
	register long *tmpl;
	register I32 anum;
	STRLEN len;

	SvSetSV(TARG, sv);
	tmps = SvPV_force(TARG, len);
	anum = len;
#ifdef LIBERAL
	for ( ; anum && (unsigned long)tmps % sizeof(long); anum--, tmps++)
	    *tmps = ~*tmps;
	tmpl = (long*)tmps;
	for ( ; anum >= sizeof(long); anum -= sizeof(long), tmpl++)
	    *tmpl = ~*tmpl;
	tmps = (char*)tmpl;
#endif
	for ( ; anum > 0; anum--, tmps++)
	    *tmps = ~*tmps;

	SETs(TARG);
      }
      RETURN;
    }
}

/* integer versions of some of the above */

PP(pp_i_multiply)
{
    djSP; dATARGET; tryAMAGICbin(mult,opASSIGN);
    {
      dPOPTOPiirl;
      SETi( left * right );
      RETURN;
    }
}

PP(pp_i_divide)
{
    djSP; dATARGET; tryAMAGICbin(div,opASSIGN);
    {
      dPOPiv;
      if (value == 0)
	DIE("Illegal division by zero");
      value = POPi / value;
      PUSHi( value );
      RETURN;
    }
}

PP(pp_i_modulo)
{
    djSP; dATARGET; tryAMAGICbin(modulo,opASSIGN); 
    {
      dPOPTOPiirl;
      if (!right)
	DIE("Illegal modulus zero");
      SETi( left % right );
      RETURN;
    }
}

PP(pp_i_add)
{
    djSP; dATARGET; tryAMAGICbin(add,opASSIGN);
    {
      dPOPTOPiirl;
      SETi( left + right );
      RETURN;
    }
}

PP(pp_i_subtract)
{
    djSP; dATARGET; tryAMAGICbin(subtr,opASSIGN);
    {
      dPOPTOPiirl;
      SETi( left - right );
      RETURN;
    }
}

PP(pp_i_lt)
{
    djSP; tryAMAGICbinSET(lt,0);
    {
      dPOPTOPiirl;
      SETs(boolSV(left < right));
      RETURN;
    }
}

PP(pp_i_gt)
{
    djSP; tryAMAGICbinSET(gt,0);
    {
      dPOPTOPiirl;
      SETs(boolSV(left > right));
      RETURN;
    }
}

PP(pp_i_le)
{
    djSP; tryAMAGICbinSET(le,0);
    {
      dPOPTOPiirl;
      SETs(boolSV(left <= right));
      RETURN;
    }
}

PP(pp_i_ge)
{
    djSP; tryAMAGICbinSET(ge,0);
    {
      dPOPTOPiirl;
      SETs(boolSV(left >= right));
      RETURN;
    }
}

PP(pp_i_eq)
{
    djSP; tryAMAGICbinSET(eq,0);
    {
      dPOPTOPiirl;
      SETs(boolSV(left == right));
      RETURN;
    }
}

PP(pp_i_ne)
{
    djSP; tryAMAGICbinSET(ne,0);
    {
      dPOPTOPiirl;
      SETs(boolSV(left != right));
      RETURN;
    }
}

PP(pp_i_ncmp)
{
    djSP; dTARGET; tryAMAGICbin(ncmp,0);
    {
      dPOPTOPiirl;
      I32 value;

      if (left > right)
	value = 1;
      else if (left < right)
	value = -1;
      else
	value = 0;
      SETi(value);
      RETURN;
    }
}

PP(pp_i_negate)
{
    djSP; dTARGET; tryAMAGICun(neg);
    SETi(-TOPi);
    RETURN;
}

/* High falutin' math. */

PP(pp_atan2)
{
    djSP; dTARGET; tryAMAGICbin(atan2,0);
    {
      dPOPTOPnnrl;
      SETn(atan2(left, right));
      RETURN;
    }
}

PP(pp_sin)
{
    djSP; dTARGET; tryAMAGICun(sin);
    {
      double value;
      value = POPn;
      value = sin(value);
      XPUSHn(value);
      RETURN;
    }
}

PP(pp_cos)
{
    djSP; dTARGET; tryAMAGICun(cos);
    {
      double value;
      value = POPn;
      value = cos(value);
      XPUSHn(value);
      RETURN;
    }
}

/* Support Configure command-line overrides for rand() functions.
   After 5.005, perhaps we should replace this by Configure support
   for drand48(), random(), or rand().  For 5.005, though, maintain
   compatibility by calling rand() but allow the user to override it.
   See INSTALL for details.  --Andy Dougherty  15 July 1998
*/
#ifndef my_rand
#  define my_rand	rand
#endif
#ifndef my_srand
#  define my_srand	srand
#endif

PP(pp_rand)
{
    djSP; dTARGET;
    double value;
    if (MAXARG < 1)
	value = 1.0;
    else
	value = POPn;
    if (value == 0.0)
	value = 1.0;
    if (!srand_called) {
	(void)my_srand((unsigned)seed());
	srand_called = TRUE;
    }
#if RANDBITS == 31
    value = my_rand() * value / 2147483648.0;
#else
#if RANDBITS == 16
    value = my_rand() * value / 65536.0;
#else
#if RANDBITS == 15
    value = my_rand() * value / 32768.0;
#else
    value = my_rand() * value / (double)(((unsigned long)1) << RANDBITS);
#endif
#endif
#endif
    XPUSHn(value);
    RETURN;
}

PP(pp_srand)
{
    djSP;
    UV anum;
    if (MAXARG < 1)
	anum = seed();
    else
	anum = POPu;
    (void)my_srand((unsigned)anum);
    srand_called = TRUE;
    EXTEND(SP, 1);
    RETPUSHYES;
}

STATIC U32
seed(void)
{
    /*
     * This is really just a quick hack which grabs various garbage
     * values.  It really should be a real hash algorithm which
     * spreads the effect of every input bit onto every output bit,
     * if someone who knows about such tings would bother to write it.
     * Might be a good idea to add that function to CORE as well.
     * No numbers below come from careful analysis or anyting here,
     * except they are primes and SEED_C1 > 1E6 to get a full-width
     * value from (tv_sec * SEED_C1 + tv_usec).  The multipliers should
     * probably be bigger too.
     */
#if RANDBITS > 16
#  define SEED_C1	1000003
#define   SEED_C4	73819
#else
#  define SEED_C1	25747
#define   SEED_C4	20639
#endif
#define   SEED_C2	3
#define   SEED_C3	269
#define   SEED_C5	26107

    dTHR;
    U32 u;
#ifdef VMS
#  include <starlet.h>
    /* when[] = (low 32 bits, high 32 bits) of time since epoch
     * in 100-ns units, typically incremented ever 10 ms.        */
    unsigned int when[2];
    _ckvmssts(sys$gettim(when));
    u = (U32)SEED_C1 * when[0] + (U32)SEED_C2 * when[1];
#else
#  ifdef HAS_GETTIMEOFDAY
    struct timeval when;
    gettimeofday(&when,(struct timezone *) 0);
    u = (U32)SEED_C1 * when.tv_sec + (U32)SEED_C2 * when.tv_usec;
#  else
    Time_t when;
    (void)time(&when);
    u = (U32)SEED_C1 * when;
#  endif
#endif
    u += SEED_C3 * (U32)getpid();
    u += SEED_C4 * (U32)(UV)PL_stack_sp;
#ifndef PLAN9           /* XXX Plan9 assembler chokes on this; fix needed  */
    u += SEED_C5 * (U32)(UV)&when;
#endif
    return u;
}

PP(pp_exp)
{
    djSP; dTARGET; tryAMAGICun(exp);
    {
      double value;
      value = POPn;
      value = exp(value);
      XPUSHn(value);
      RETURN;
    }
}

PP(pp_log)
{
    djSP; dTARGET; tryAMAGICun(log);
    {
      double value;
      value = POPn;
      if (value <= 0.0) {
	SET_NUMERIC_STANDARD();
	DIE("Can't take log of %g", value);
      }
      value = log(value);
      XPUSHn(value);
      RETURN;
    }
}

PP(pp_sqrt)
{
    djSP; dTARGET; tryAMAGICun(sqrt);
    {
      double value;
      value = POPn;
      if (value < 0.0) {
	SET_NUMERIC_STANDARD();
	DIE("Can't take sqrt of %g", value);
      }
      value = sqrt(value);
      XPUSHn(value);
      RETURN;
    }
}

PP(pp_int)
{
    djSP; dTARGET;
    {
      double value = TOPn;
      IV iv;

      if (SvIOKp(TOPs) && !SvNOKp(TOPs) && !SvPOKp(TOPs)) {
	iv = SvIVX(TOPs);
	SETi(iv);
      }
      else {
	if (value >= 0.0)
	  (void)modf(value, &value);
	else {
	  (void)modf(-value, &value);
	  value = -value;
	}
	iv = I_V(value);
	if (iv == value)
	  SETi(iv);
	else
	  SETn(value);
      }
    }
    RETURN;
}

PP(pp_abs)
{
    djSP; dTARGET; tryAMAGICun(abs);
    {
      double value = TOPn;
      IV iv;

      if (SvIOKp(TOPs) && !SvNOKp(TOPs) && !SvPOKp(TOPs) &&
	  (iv = SvIVX(TOPs)) != IV_MIN) {
	if (iv < 0)
	  iv = -iv;
	SETi(iv);
      }
      else {
	if (value < 0.0)
	    value = -value;
	SETn(value);
      }
    }
    RETURN;
}

PP(pp_hex)
{
    djSP; dTARGET;
    char *tmps;
    I32 argtype;

    tmps = POPp;
    XPUSHu(scan_hex(tmps, 99, &argtype));
    RETURN;
}

PP(pp_oct)
{
    djSP; dTARGET;
    UV value;
    I32 argtype;
    char *tmps;

    tmps = POPp;
    while (*tmps && isSPACE(*tmps))
	tmps++;
    if (*tmps == '0')
	tmps++;
    if (*tmps == 'x')
	value = scan_hex(++tmps, 99, &argtype);
    else
	value = scan_oct(tmps, 99, &argtype);
    XPUSHu(value);
    RETURN;
}

/* String stuff. */

PP(pp_length)
{
    djSP; dTARGET;
    SETi( sv_len(TOPs) );
    RETURN;
}

PP(pp_substr)
{
    djSP; dTARGET;
    SV *sv;
    I32 len;
    STRLEN curlen;
    I32 pos;
    I32 rem;
    I32 fail;
    I32 lvalue = PL_op->op_flags & OPf_MOD;
    char *tmps;
    I32 arybase = PL_curcop->cop_arybase;
    char *repl = 0;
    STRLEN repl_len;

    SvTAINTED_off(TARG);			/* decontaminate */
    if (MAXARG > 2) {
	if (MAXARG > 3) {
	    sv = POPs;
	    repl = SvPV(sv, repl_len);
	}
	len = POPi;
    }
    pos = POPi;
    sv = POPs;
    PUTBACK;
    tmps = SvPV(sv, curlen);
    if (pos >= arybase) {
	pos -= arybase;
	rem = curlen-pos;
	fail = rem;
	if (MAXARG > 2) {
	    if (len < 0) {
		rem += len;
		if (rem < 0)
		    rem = 0;
	    }
	    else if (rem > len)
		     rem = len;
	}
    }
    else {
	pos += curlen;
	if (MAXARG < 3)
	    rem = curlen;
	else if (len >= 0) {
	    rem = pos+len;
	    if (rem > (I32)curlen)
		rem = curlen;
	}
	else {
	    rem = curlen+len;
	    if (rem < pos)
		rem = pos;
	}
	if (pos < 0)
	    pos = 0;
	fail = rem;
	rem -= pos;
    }
    if (fail < 0) {
	if (PL_dowarn || lvalue || repl)
	    warn("substr outside of string");
	RETPUSHUNDEF;
    }
    else {
	tmps += pos;
	sv_setpvn(TARG, tmps, rem);
	if (lvalue) {			/* it's an lvalue! */
	    if (!SvGMAGICAL(sv)) {
		if (SvROK(sv)) {
		    SvPV_force(sv,PL_na);
		    if (PL_dowarn)
			warn("Attempt to use reference as lvalue in substr");
		}
		if (SvOK(sv))		/* is it defined ? */
		    (void)SvPOK_only(sv);
		else
		    sv_setpvn(sv,"",0);	/* avoid lexical reincarnation */
	    }

	    if (SvTYPE(TARG) < SVt_PVLV) {
		sv_upgrade(TARG, SVt_PVLV);
		sv_magic(TARG, Nullsv, 'x', Nullch, 0);
	    }

	    LvTYPE(TARG) = 'x';
	    if (LvTARG(TARG) != sv) {
		if (LvTARG(TARG))
		    SvREFCNT_dec(LvTARG(TARG));
		LvTARG(TARG) = SvREFCNT_inc(sv);
	    }
	    LvTARGOFF(TARG) = pos;
	    LvTARGLEN(TARG) = rem;
	}
	else if (repl)
	    sv_insert(sv, pos, rem, repl, repl_len);
    }
    SPAGAIN;
    PUSHs(TARG);		/* avoid SvSETMAGIC here */
    RETURN;
}

PP(pp_vec)
{
    djSP; dTARGET;
    register I32 size = POPi;
    register I32 offset = POPi;
    register SV *src = POPs;
    I32 lvalue = PL_op->op_flags & OPf_MOD;
    STRLEN srclen;
    unsigned char *s = (unsigned char*)SvPV(src, srclen);
    unsigned long retnum;
    I32 len;

    SvTAINTED_off(TARG);			/* decontaminate */
    offset *= size;		/* turn into bit offset */
    len = (offset + size + 7) / 8;
    if (offset < 0 || size < 1)
	retnum = 0;
    else {
	if (lvalue) {                      /* it's an lvalue! */
	    if (SvTYPE(TARG) < SVt_PVLV) {
		sv_upgrade(TARG, SVt_PVLV);
		sv_magic(TARG, Nullsv, 'v', Nullch, 0);
	    }

	    LvTYPE(TARG) = 'v';
	    if (LvTARG(TARG) != src) {
		if (LvTARG(TARG))
		    SvREFCNT_dec(LvTARG(TARG));
		LvTARG(TARG) = SvREFCNT_inc(src);
	    }
	    LvTARGOFF(TARG) = offset;
	    LvTARGLEN(TARG) = size;
	}
	if (len > srclen) {
	    if (size <= 8)
		retnum = 0;
	    else {
		offset >>= 3;
		if (size == 16) {
		    if (offset >= srclen)
			retnum = 0;
		    else
			retnum = (unsigned long) s[offset] << 8;
		}
		else if (size == 32) {
		    if (offset >= srclen)
			retnum = 0;
		    else if (offset + 1 >= srclen)
			retnum = (unsigned long) s[offset] << 24;
		    else if (offset + 2 >= srclen)
			retnum = ((unsigned long) s[offset] << 24) +
			    ((unsigned long) s[offset + 1] << 16);
		    else
			retnum = ((unsigned long) s[offset] << 24) +
			    ((unsigned long) s[offset + 1] << 16) +
			    (s[offset + 2] << 8);
		}
	    }
	}
	else if (size < 8)
	    retnum = (s[offset >> 3] >> (offset & 7)) & ((1 << size) - 1);
	else {
	    offset >>= 3;
	    if (size == 8)
		retnum = s[offset];
	    else if (size == 16)
		retnum = ((unsigned long) s[offset] << 8) + s[offset+1];
	    else if (size == 32)
		retnum = ((unsigned long) s[offset] << 24) +
			((unsigned long) s[offset + 1] << 16) +
			(s[offset + 2] << 8) + s[offset+3];
	}
    }

    sv_setuv(TARG, (UV)retnum);
    PUSHs(TARG);
    RETURN;
}

PP(pp_index)
{
    djSP; dTARGET;
    SV *big;
    SV *little;
    I32 offset;
    I32 retval;
    char *tmps;
    char *tmps2;
    STRLEN biglen;
    I32 arybase = PL_curcop->cop_arybase;

    if (MAXARG < 3)
	offset = 0;
    else
	offset = POPi - arybase;
    little = POPs;
    big = POPs;
    tmps = SvPV(big, biglen);
    if (offset < 0)
	offset = 0;
    else if (offset > biglen)
	offset = biglen;
    if (!(tmps2 = fbm_instr((unsigned char*)tmps + offset,
      (unsigned char*)tmps + biglen, little, 0)))
	retval = -1 + arybase;
    else
	retval = tmps2 - tmps + arybase;
    PUSHi(retval);
    RETURN;
}

PP(pp_rindex)
{
    djSP; dTARGET;
    SV *big;
    SV *little;
    STRLEN blen;
    STRLEN llen;
    SV *offstr;
    I32 offset;
    I32 retval;
    char *tmps;
    char *tmps2;
    I32 arybase = PL_curcop->cop_arybase;

    if (MAXARG >= 3)
	offstr = POPs;
    little = POPs;
    big = POPs;
    tmps2 = SvPV(little, llen);
    tmps = SvPV(big, blen);
    if (MAXARG < 3)
	offset = blen;
    else
	offset = SvIV(offstr) - arybase + llen;
    if (offset < 0)
	offset = 0;
    else if (offset > blen)
	offset = blen;
    if (!(tmps2 = rninstr(tmps,  tmps  + offset,
			  tmps2, tmps2 + llen)))
	retval = -1 + arybase;
    else
	retval = tmps2 - tmps + arybase;
    PUSHi(retval);
    RETURN;
}

PP(pp_sprintf)
{
    djSP; dMARK; dORIGMARK; dTARGET;
#ifdef USE_LOCALE_NUMERIC
    if (PL_op->op_private & OPpLOCALE)
	SET_NUMERIC_LOCAL();
    else
	SET_NUMERIC_STANDARD();
#endif
    do_sprintf(TARG, SP-MARK, MARK+1);
    TAINT_IF(SvTAINTED(TARG));
    SP = ORIGMARK;
    PUSHTARG;
    RETURN;
}

PP(pp_ord)
{
    djSP; dTARGET;
    I32 value;
    char *tmps;

#ifndef I286
    tmps = POPp;
    value = (I32) (*tmps & 255);
#else
    I32 anum;
    tmps = POPp;
    anum = (I32) *tmps;
    value = (I32) (anum & 255);
#endif
    XPUSHi(value);
    RETURN;
}

PP(pp_chr)
{
    djSP; dTARGET;
    char *tmps;

    (void)SvUPGRADE(TARG,SVt_PV);
    SvGROW(TARG,2);
    SvCUR_set(TARG, 1);
    tmps = SvPVX(TARG);
    *tmps++ = POPi;
    *tmps = '\0';
    (void)SvPOK_only(TARG);
    XPUSHs(TARG);
    RETURN;
}

PP(pp_crypt)
{
    djSP; dTARGET; dPOPTOPssrl;
#ifdef HAS_CRYPT
    char *tmps = SvPV(left, PL_na);
#ifdef FCRYPT
    sv_setpv(TARG, fcrypt(tmps, SvPV(right, PL_na)));
#else
    sv_setpv(TARG, PerlProc_crypt(tmps, SvPV(right, PL_na)));
#endif
#else
    DIE(
      "The crypt() function is unimplemented due to excessive paranoia.");
#endif
    SETs(TARG);
    RETURN;
}

PP(pp_ucfirst)
{
    djSP;
    SV *sv = TOPs;
    register char *s;

    if (!SvPADTMP(sv)) {
	dTARGET;
	sv_setsv(TARG, sv);
	sv = TARG;
	SETs(sv);
    }
    s = SvPV_force(sv, PL_na);
    if (*s) {
	if (PL_op->op_private & OPpLOCALE) {
	    TAINT;
	    SvTAINTED_on(sv);
	    *s = toUPPER_LC(*s);
	}
	else
	    *s = toUPPER(*s);
    }

    RETURN;
}

PP(pp_lcfirst)
{
    djSP;
    SV *sv = TOPs;
    register char *s;

    if (!SvPADTMP(sv)) {
	dTARGET;
	sv_setsv(TARG, sv);
	sv = TARG;
	SETs(sv);
    }
    s = SvPV_force(sv, PL_na);
    if (*s) {
	if (PL_op->op_private & OPpLOCALE) {
	    TAINT;
	    SvTAINTED_on(sv);
	    *s = toLOWER_LC(*s);
	}
	else
	    *s = toLOWER(*s);
    }

    SETs(sv);
    RETURN;
}

PP(pp_uc)
{
    djSP;
    SV *sv = TOPs;
    register char *s;
    STRLEN len;

    if (!SvPADTMP(sv)) {
	dTARGET;
	sv_setsv(TARG, sv);
	sv = TARG;
	SETs(sv);
    }

    s = SvPV_force(sv, len);
    if (len) {
	register char *send = s + len;

	if (PL_op->op_private & OPpLOCALE) {
	    TAINT;
	    SvTAINTED_on(sv);
	    for (; s < send; s++)
		*s = toUPPER_LC(*s);
	}
	else {
	    for (; s < send; s++)
		*s = toUPPER(*s);
	}
    }
    RETURN;
}

PP(pp_lc)
{
    djSP;
    SV *sv = TOPs;
    register char *s;
    STRLEN len;

    if (!SvPADTMP(sv)) {
	dTARGET;
	sv_setsv(TARG, sv);
	sv = TARG;
	SETs(sv);
    }

    s = SvPV_force(sv, len);
    if (len) {
	register char *send = s + len;

	if (PL_op->op_private & OPpLOCALE) {
	    TAINT;
	    SvTAINTED_on(sv);
	    for (; s < send; s++)
		*s = toLOWER_LC(*s);
	}
	else {
	    for (; s < send; s++)
		*s = toLOWER(*s);
	}
    }
    RETURN;
}

PP(pp_quotemeta)
{
    djSP; dTARGET;
    SV *sv = TOPs;
    STRLEN len;
    register char *s = SvPV(sv,len);
    register char *d;

    if (len) {
	(void)SvUPGRADE(TARG, SVt_PV);
	SvGROW(TARG, (len * 2) + 1);
	d = SvPVX(TARG);
	while (len--) {
	    if (!isALNUM(*s))
		*d++ = '\\';
	    *d++ = *s++;
	}
	*d = '\0';
	SvCUR_set(TARG, d - SvPVX(TARG));
	(void)SvPOK_only(TARG);
    }
    else
	sv_setpvn(TARG, s, len);
    SETs(TARG);
    RETURN;
}

/* Arrays. */

PP(pp_aslice)
{
    djSP; dMARK; dORIGMARK;
    register SV** svp;
    register AV* av = (AV*)POPs;
    register I32 lval = PL_op->op_flags & OPf_MOD;
    I32 arybase = PL_curcop->cop_arybase;
    I32 elem;

    if (SvTYPE(av) == SVt_PVAV) {
	if (lval && PL_op->op_private & OPpLVAL_INTRO) {
	    I32 max = -1;
	    for (svp = MARK + 1; svp <= SP; svp++) {
		elem = SvIVx(*svp);
		if (elem > max)
		    max = elem;
	    }
	    if (max > AvMAX(av))
		av_extend(av, max);
	}
	while (++MARK <= SP) {
	    elem = SvIVx(*MARK);

	    if (elem > 0)
		elem -= arybase;
	    svp = av_fetch(av, elem, lval);
	    if (lval) {
		if (!svp || *svp == &PL_sv_undef)
		    DIE(no_aelem, elem);
		if (PL_op->op_private & OPpLVAL_INTRO)
		    save_aelem(av, elem, svp);
	    }
	    *MARK = svp ? *svp : &PL_sv_undef;
	}
    }
    if (GIMME != G_ARRAY) {
	MARK = ORIGMARK;
	*++MARK = *SP;
	SP = MARK;
    }
    RETURN;
}

/* Associative arrays. */

PP(pp_each)
{
    djSP; dTARGET;
    HV *hash = (HV*)POPs;
    HE *entry;
    I32 gimme = GIMME_V;
    I32 realhv = (SvTYPE(hash) == SVt_PVHV);

    PUTBACK;
    /* might clobber stack_sp */
    entry = realhv ? hv_iternext(hash) : avhv_iternext((AV*)hash);
    SPAGAIN;

    EXTEND(SP, 2);
    if (entry) {
	PUSHs(hv_iterkeysv(entry));	/* won't clobber stack_sp */
	if (gimme == G_ARRAY) {
	    PUTBACK;
	    /* might clobber stack_sp */
	    sv_setsv(TARG, realhv ?
		     hv_iterval(hash, entry) : avhv_iterval((AV*)hash, entry));
	    SPAGAIN;
	    PUSHs(TARG);
	}
    }
    else if (gimme == G_SCALAR)
	RETPUSHUNDEF;

    RETURN;
}

PP(pp_values)
{
    return do_kv(ARGS);
}

PP(pp_keys)
{
    return do_kv(ARGS);
}

PP(pp_delete)
{
    djSP;
    I32 gimme = GIMME_V;
    I32 discard = (gimme == G_VOID) ? G_DISCARD : 0;
    SV *sv;
    HV *hv;

    if (PL_op->op_private & OPpSLICE) {
	dMARK; dORIGMARK;
	U32 hvtype;
	hv = (HV*)POPs;
	hvtype = SvTYPE(hv);
	while (++MARK <= SP) {
	    if (hvtype == SVt_PVHV)
		sv = hv_delete_ent(hv, *MARK, discard, 0);
	    else
		DIE("Not a HASH reference");
	    *MARK = sv ? sv : &PL_sv_undef;
	}
	if (discard)
	    SP = ORIGMARK;
	else if (gimme == G_SCALAR) {
	    MARK = ORIGMARK;
	    *++MARK = *SP;
	    SP = MARK;
	}
    }
    else {
	SV *keysv = POPs;
	hv = (HV*)POPs;
	if (SvTYPE(hv) == SVt_PVHV)
	    sv = hv_delete_ent(hv, keysv, discard, 0);
	else
	    DIE("Not a HASH reference");
	if (!sv)
	    sv = &PL_sv_undef;
	if (!discard)
	    PUSHs(sv);
    }
    RETURN;
}

PP(pp_exists)
{
    djSP;
    SV *tmpsv = POPs;
    HV *hv = (HV*)POPs;
    if (SvTYPE(hv) == SVt_PVHV) {
	if (hv_exists_ent(hv, tmpsv, 0))
	    RETPUSHYES;
    } else if (SvTYPE(hv) == SVt_PVAV) {
	if (avhv_exists_ent((AV*)hv, tmpsv, 0))
	    RETPUSHYES;
    } else {
	DIE("Not a HASH reference");
    }
    RETPUSHNO;
}

PP(pp_hslice)
{
    djSP; dMARK; dORIGMARK;
    register HV *hv = (HV*)POPs;
    register I32 lval = PL_op->op_flags & OPf_MOD;
    I32 realhv = (SvTYPE(hv) == SVt_PVHV);

    if (!realhv && PL_op->op_private & OPpLVAL_INTRO)
	DIE("Can't localize pseudo-hash element");

    if (realhv || SvTYPE(hv) == SVt_PVAV) {
	while (++MARK <= SP) {
	    SV *keysv = *MARK;
	    SV **svp;
	    if (realhv) {
		HE *he = hv_fetch_ent(hv, keysv, lval, 0);
		svp = he ? &HeVAL(he) : 0;
	    } else {
		svp = avhv_fetch_ent((AV*)hv, keysv, lval, 0);
	    }
	    if (lval) {
		if (!svp || *svp == &PL_sv_undef)
		    DIE(no_helem, SvPV(keysv, PL_na));
		if (PL_op->op_private & OPpLVAL_INTRO)
		    save_helem(hv, keysv, svp);
	    }
	    *MARK = svp ? *svp : &PL_sv_undef;
	}
    }
    if (GIMME != G_ARRAY) {
	MARK = ORIGMARK;
	*++MARK = *SP;
	SP = MARK;
    }
    RETURN;
}

/* List operators. */

PP(pp_list)
{
    djSP; dMARK;
    if (GIMME != G_ARRAY) {
	if (++MARK <= SP)
	    *MARK = *SP;		/* unwanted list, return last item */
	else
	    *MARK = &PL_sv_undef;
	SP = MARK;
    }
    RETURN;
}

PP(pp_lslice)
{
    djSP;
    SV **lastrelem = PL_stack_sp;
    SV **lastlelem = PL_stack_base + POPMARK;
    SV **firstlelem = PL_stack_base + POPMARK + 1;
    register SV **firstrelem = lastlelem + 1;
    I32 arybase = PL_curcop->cop_arybase;
    I32 lval = PL_op->op_flags & OPf_MOD;
    I32 is_something_there = lval;

    register I32 max = lastrelem - lastlelem;
    register SV **lelem;
    register I32 ix;

    if (GIMME != G_ARRAY) {
	ix = SvIVx(*lastlelem);
	if (ix < 0)
	    ix += max;
	else
	    ix -= arybase;
	if (ix < 0 || ix >= max)
	    *firstlelem = &PL_sv_undef;
	else
	    *firstlelem = firstrelem[ix];
	SP = firstlelem;
	RETURN;
    }

    if (max == 0) {
	SP = firstlelem - 1;
	RETURN;
    }

    for (lelem = firstlelem; lelem <= lastlelem; lelem++) {
	ix = SvIVx(*lelem);
	if (ix < 0) {
	    ix += max;
	    if (ix < 0)
		*lelem = &PL_sv_undef;
	    else if (!(*lelem = firstrelem[ix]))
		*lelem = &PL_sv_undef;
	}
	else {
	    ix -= arybase;
	    if (ix >= max || !(*lelem = firstrelem[ix]))
		*lelem = &PL_sv_undef;
	}
	if (!is_something_there && (SvOK(*lelem) || SvGMAGICAL(*lelem)))
	    is_something_there = TRUE;
    }
    if (is_something_there)
	SP = lastlelem;
    else
	SP = firstlelem - 1;
    RETURN;
}

PP(pp_anonlist)
{
    djSP; dMARK; dORIGMARK;
    I32 items = SP - MARK;
    SV *av = sv_2mortal((SV*)av_make(items, MARK+1));
    SP = ORIGMARK;		/* av_make() might realloc stack_sp */
    XPUSHs(av);
    RETURN;
}

PP(pp_anonhash)
{
    djSP; dMARK; dORIGMARK;
    HV* hv = (HV*)sv_2mortal((SV*)newHV());

    while (MARK < SP) {
	SV* key = *++MARK;
	SV *val = NEWSV(46, 0);
	if (MARK < SP)
	    sv_setsv(val, *++MARK);
	else if (PL_dowarn)
	    warn("Odd number of elements in hash assignment");
	(void)hv_store_ent(hv,key,val,0);
    }
    SP = ORIGMARK;
    XPUSHs((SV*)hv);
    RETURN;
}

PP(pp_splice)
{
    djSP; dMARK; dORIGMARK;
    register AV *ary = (AV*)*++MARK;
    register SV **src;
    register SV **dst;
    register I32 i;
    register I32 offset;
    register I32 length;
    I32 newlen;
    I32 after;
    I32 diff;
    SV **tmparyval = 0;
    MAGIC *mg;

    if (SvRMAGICAL(ary) && (mg = mg_find((SV*)ary,'P'))) {
	*MARK-- = mg->mg_obj;
	PUSHMARK(MARK);
	PUTBACK;
	ENTER;
	perl_call_method("SPLICE",GIMME_V);
	LEAVE;
	SPAGAIN;
	RETURN;
    }

    SP++;

    if (++MARK < SP) {
	offset = i = SvIVx(*MARK);
	if (offset < 0)
	    offset += AvFILLp(ary) + 1;
	else
	    offset -= PL_curcop->cop_arybase;
	if (offset < 0)
	    DIE(no_aelem, i);
	if (++MARK < SP) {
	    length = SvIVx(*MARK++);
	    if (length < 0) {
		length += AvFILLp(ary) - offset + 1;
		if (length < 0)
		    length = 0;
	    }
	}
	else
	    length = AvMAX(ary) + 1;		/* close enough to infinity */
    }
    else {
	offset = 0;
	length = AvMAX(ary) + 1;
    }
    if (offset > AvFILLp(ary) + 1)
	offset = AvFILLp(ary) + 1;
    after = AvFILLp(ary) + 1 - (offset + length);
    if (after < 0) {				/* not that much array */
	length += after;			/* offset+length now in array */
	after = 0;
	if (!AvALLOC(ary))
	    av_extend(ary, 0);
    }

    /* At this point, MARK .. SP-1 is our new LIST */

    newlen = SP - MARK;
    diff = newlen - length;
    if (newlen && !AvREAL(ary)) {
	if (AvREIFY(ary))
	    av_reify(ary);
	else
	    assert(AvREAL(ary));		/* would leak, so croak */
    }

    if (diff < 0) {				/* shrinking the area */
	if (newlen) {
	    New(451, tmparyval, newlen, SV*);	/* so remember insertion */
	    Copy(MARK, tmparyval, newlen, SV*);
	}

	MARK = ORIGMARK + 1;
	if (GIMME == G_ARRAY) {			/* copy return vals to stack */
	    MEXTEND(MARK, length);
	    Copy(AvARRAY(ary)+offset, MARK, length, SV*);
	    if (AvREAL(ary)) {
		EXTEND_MORTAL(length);
		for (i = length, dst = MARK; i; i--) {
		    sv_2mortal(*dst);	/* free them eventualy */
		    dst++;
		}
	    }
	    MARK += length - 1;
	}
	else {
	    *MARK = AvARRAY(ary)[offset+length-1];
	    if (AvREAL(ary)) {
		sv_2mortal(*MARK);
		for (i = length - 1, dst = &AvARRAY(ary)[offset]; i > 0; i--)
		    SvREFCNT_dec(*dst++);	/* free them now */
	    }
	}
	AvFILLp(ary) += diff;

	/* pull up or down? */

	if (offset < after) {			/* easier to pull up */
	    if (offset) {			/* esp. if nothing to pull */
		src = &AvARRAY(ary)[offset-1];
		dst = src - diff;		/* diff is negative */
		for (i = offset; i > 0; i--)	/* can't trust Copy */
		    *dst-- = *src--;
	    }
	    dst = AvARRAY(ary);
	    SvPVX(ary) = (char*)(AvARRAY(ary) - diff); /* diff is negative */
	    AvMAX(ary) += diff;
	}
	else {
	    if (after) {			/* anything to pull down? */
		src = AvARRAY(ary) + offset + length;
		dst = src + diff;		/* diff is negative */
		Move(src, dst, after, SV*);
	    }
	    dst = &AvARRAY(ary)[AvFILLp(ary)+1];
						/* avoid later double free */
	}
	i = -diff;
	while (i)
	    dst[--i] = &PL_sv_undef;
	
	if (newlen) {
	    for (src = tmparyval, dst = AvARRAY(ary) + offset;
	      newlen; newlen--) {
		*dst = NEWSV(46, 0);
		sv_setsv(*dst++, *src++);
	    }
	    Safefree(tmparyval);
	}
    }
    else {					/* no, expanding (or same) */
	if (length) {
	    New(452, tmparyval, length, SV*);	/* so remember deletion */
	    Copy(AvARRAY(ary)+offset, tmparyval, length, SV*);
	}

	if (diff > 0) {				/* expanding */

	    /* push up or down? */

	    if (offset < after && diff <= AvARRAY(ary) - AvALLOC(ary)) {
		if (offset) {
		    src = AvARRAY(ary);
		    dst = src - diff;
		    Move(src, dst, offset, SV*);
		}
		SvPVX(ary) = (char*)(AvARRAY(ary) - diff);/* diff is positive */
		AvMAX(ary) += diff;
		AvFILLp(ary) += diff;
	    }
	    else {
		if (AvFILLp(ary) + diff >= AvMAX(ary))	/* oh, well */
		    av_extend(ary, AvFILLp(ary) + diff);
		AvFILLp(ary) += diff;

		if (after) {
		    dst = AvARRAY(ary) + AvFILLp(ary);
		    src = dst - diff;
		    for (i = after; i; i--) {
			*dst-- = *src--;
		    }
		}
	    }
	}

	for (src = MARK, dst = AvARRAY(ary) + offset; newlen; newlen--) {
	    *dst = NEWSV(46, 0);
	    sv_setsv(*dst++, *src++);
	}
	MARK = ORIGMARK + 1;
	if (GIMME == G_ARRAY) {			/* copy return vals to stack */
	    if (length) {
		Copy(tmparyval, MARK, length, SV*);
		if (AvREAL(ary)) {
		    EXTEND_MORTAL(length);
		    for (i = length, dst = MARK; i; i--) {
			sv_2mortal(*dst);	/* free them eventualy */
			dst++;
		    }
		}
		Safefree(tmparyval);
	    }
	    MARK += length - 1;
	}
	else if (length--) {
	    *MARK = tmparyval[length];
	    if (AvREAL(ary)) {
		sv_2mortal(*MARK);
		while (length-- > 0)
		    SvREFCNT_dec(tmparyval[length]);
	    }
	    Safefree(tmparyval);
	}
	else
	    *MARK = &PL_sv_undef;
    }
    SP = MARK;
    RETURN;
}

PP(pp_push)
{
    djSP; dMARK; dORIGMARK; dTARGET;
    register AV *ary = (AV*)*++MARK;
    register SV *sv = &PL_sv_undef;
    MAGIC *mg;

    if (SvRMAGICAL(ary) && (mg = mg_find((SV*)ary,'P'))) {
	*MARK-- = mg->mg_obj;
	PUSHMARK(MARK);
	PUTBACK;
	ENTER;
	perl_call_method("PUSH",G_SCALAR|G_DISCARD);
	LEAVE;
	SPAGAIN;
    }
    else {
	/* Why no pre-extend of ary here ? */
	for (++MARK; MARK <= SP; MARK++) {
	    sv = NEWSV(51, 0);
	    if (*MARK)
		sv_setsv(sv, *MARK);
	    av_push(ary, sv);
	}
    }
    SP = ORIGMARK;
    PUSHi( AvFILL(ary) + 1 );
    RETURN;
}

PP(pp_pop)
{
    djSP;
    AV *av = (AV*)POPs;
    SV *sv = av_pop(av);
    if (AvREAL(av))
	(void)sv_2mortal(sv);
    PUSHs(sv);
    RETURN;
}

PP(pp_shift)
{
    djSP;
    AV *av = (AV*)POPs;
    SV *sv = av_shift(av);
    EXTEND(SP, 1);
    if (!sv)
	RETPUSHUNDEF;
    if (AvREAL(av))
	(void)sv_2mortal(sv);
    PUSHs(sv);
    RETURN;
}

PP(pp_unshift)
{
    djSP; dMARK; dORIGMARK; dTARGET;
    register AV *ary = (AV*)*++MARK;
    register SV *sv;
    register I32 i = 0;
    MAGIC *mg;

    if (SvRMAGICAL(ary) && (mg = mg_find((SV*)ary,'P'))) {
	*MARK-- = mg->mg_obj;
	PUSHMARK(MARK);
	PUTBACK;
	ENTER;
	perl_call_method("UNSHIFT",G_SCALAR|G_DISCARD);
	LEAVE;
	SPAGAIN;
    }
    else {
	av_unshift(ary, SP - MARK);
	while (MARK < SP) {
	    sv = NEWSV(27, 0);
	    sv_setsv(sv, *++MARK);
	    (void)av_store(ary, i++, sv);
	}
    }
    SP = ORIGMARK;
    PUSHi( AvFILL(ary) + 1 );
    RETURN;
}

PP(pp_reverse)
{
    djSP; dMARK;
    register SV *tmp;
    SV **oldsp = SP;

    if (GIMME == G_ARRAY) {
	MARK++;
	while (MARK < SP) {
	    tmp = *MARK;
	    *MARK++ = *SP;
	    *SP-- = tmp;
	}
	SP = oldsp;
    }
    else {
	register char *up;
	register char *down;
	register I32 tmp;
	dTARGET;
	STRLEN len;

	if (SP - MARK > 1)
	    do_join(TARG, &PL_sv_no, MARK, SP);
	else
	    sv_setsv(TARG, (SP > MARK) ? *SP : DEFSV);
	up = SvPV_force(TARG, len);
	if (len > 1) {
	    down = SvPVX(TARG) + len - 1;
	    while (down > up) {
		tmp = *up;
		*up++ = *down;
		*down-- = tmp;
	    }
	    (void)SvPOK_only(TARG);
	}
	SP = MARK + 1;
	SETTARG;
    }
    RETURN;
}

STATIC SV      *
mul128(SV *sv, U8 m)
{
  STRLEN          len;
  char           *s = SvPV(sv, len);
  char           *t;
  U32             i = 0;

  if (!strnEQ(s, "0000", 4)) {  /* need to grow sv */
    SV             *tmpNew = newSVpv("0000000000", 10);

    sv_catsv(tmpNew, sv);
    SvREFCNT_dec(sv);		/* free old sv */
    sv = tmpNew;
    s = SvPV(sv, len);
  }
  t = s + len - 1;
  while (!*t)                   /* trailing '\0'? */
    t--;
  while (t > s) {
    i = ((*t - '0') << 7) + m;
    *(t--) = '0' + (i % 10);
    m = i / 10;
  }
  return (sv);
}

/* Explosives and implosives. */

static const char uuemap[] =
    "`!\"#$%&'()*+,-./0123456789:;<=>?@ABCDEFGHIJKLMNOPQRSTUVWXYZ[\\]^_";
static char uudmap[256];        /* Initialised on first use */
#if 'I' == 73 && 'J' == 74
/* On an ASCII/ISO kind of system */
#define ISUUCHAR(ch)    ((ch) >= ' ' && (ch) < 'a')
#else
/*
  Some other sort of character set - use memchr() so we don't match
  the null byte.
 */
#define ISUUCHAR(ch)    (memchr(uuemap, (ch), sizeof(uuemap)-1) || (ch) == ' ')
#endif

PP(pp_unpack)
{
    djSP;
    dPOPPOPssrl;
    SV **oldsp = SP;
    I32 gimme = GIMME_V;
    SV *sv;
    STRLEN llen;
    STRLEN rlen;
    register char *pat = SvPV(left, llen);
    register char *s = SvPV(right, rlen);
    char *strend = s + rlen;
    char *strbeg = s;
    register char *patend = pat + llen;
    I32 datumtype;
    register I32 len;
    register I32 bits;

    /* These must not be in registers: */
    I16 ashort;
    int aint;
    I32 along;
#ifdef HAS_QUAD
    Quad_t aquad;
#endif
    U16 aushort;
    unsigned int auint;
    U32 aulong;
#ifdef HAS_QUAD
    unsigned Quad_t auquad;
#endif
    char *aptr;
    float afloat;
    double adouble;
    I32 checksum = 0;
    register U32 culong;
    double cdouble;
    static char* bitcount = 0;
    int commas = 0;

    if (gimme != G_ARRAY) {		/* arrange to do first one only */
	/*SUPPRESS 530*/
	for (patend = pat; !isALPHA(*patend) || *patend == 'x'; patend++) ;
	if (strchr("aAbBhHP", *patend) || *pat == '%') {
	    patend++;
	    while (isDIGIT(*patend) || *patend == '*')
		patend++;
	}
	else
	    patend++;
    }
    while (pat < patend) {
      reparse:
	datumtype = *pat++ & 0xFF;
	if (isSPACE(datumtype))
	    continue;
	if (pat >= patend)
	    len = 1;
	else if (*pat == '*') {
	    len = strend - strbeg;	/* long enough */
	    pat++;
	}
	else if (isDIGIT(*pat)) {
	    len = *pat++ - '0';
	    while (isDIGIT(*pat))
		len = (len * 10) + (*pat++ - '0');
	}
	else
	    len = (datumtype != '@');
	switch(datumtype) {
	default:
	    croak("Invalid type in unpack: '%c'", (int)datumtype);
	case ',': /* grandfather in commas but with a warning */
	    if (commas++ == 0 && PL_dowarn)
		warn("Invalid type in unpack: '%c'", (int)datumtype);
	    break;
	case '%':
	    if (len == 1 && pat[-1] != '1')
		len = 16;
	    checksum = len;
	    culong = 0;
	    cdouble = 0;
	    if (pat < patend)
		goto reparse;
	    break;
	case '@':
	    if (len > strend - strbeg)
		DIE("@ outside of string");
	    s = strbeg + len;
	    break;
	case 'X':
	    if (len > s - strbeg)
		DIE("X outside of string");
	    s -= len;
	    break;
	case 'x':
	    if (len > strend - s)
		DIE("x outside of string");
	    s += len;
	    break;
	case 'A':
	case 'a':
	    if (len > strend - s)
		len = strend - s;
	    if (checksum)
		goto uchar_checksum;
	    sv = NEWSV(35, len);
	    sv_setpvn(sv, s, len);
	    s += len;
	    if (datumtype == 'A') {
		aptr = s;	/* borrow register */
		s = SvPVX(sv) + len - 1;
		while (s >= SvPVX(sv) && (!*s || isSPACE(*s)))
		    s--;
		*++s = '\0';
		SvCUR_set(sv, s - SvPVX(sv));
		s = aptr;	/* unborrow register */
	    }
	    XPUSHs(sv_2mortal(sv));
	    break;
	case 'B':
	case 'b':
	    if (pat[-1] == '*' || len > (strend - s) * 8)
		len = (strend - s) * 8;
	    if (checksum) {
		if (!bitcount) {
		    Newz(601, bitcount, 256, char);
		    for (bits = 1; bits < 256; bits++) {
			if (bits & 1)	bitcount[bits]++;
			if (bits & 2)	bitcount[bits]++;
			if (bits & 4)	bitcount[bits]++;
			if (bits & 8)	bitcount[bits]++;
			if (bits & 16)	bitcount[bits]++;
			if (bits & 32)	bitcount[bits]++;
			if (bits & 64)	bitcount[bits]++;
			if (bits & 128)	bitcount[bits]++;
		    }
		}
		while (len >= 8) {
		    culong += bitcount[*(unsigned char*)s++];
		    len -= 8;
		}
		if (len) {
		    bits = *s;
		    if (datumtype == 'b') {
			while (len-- > 0) {
			    if (bits & 1) culong++;
			    bits >>= 1;
			}
		    }
		    else {
			while (len-- > 0) {
			    if (bits & 128) culong++;
			    bits <<= 1;
			}
		    }
		}
		break;
	    }
	    sv = NEWSV(35, len + 1);
	    SvCUR_set(sv, len);
	    SvPOK_on(sv);
	    aptr = pat;			/* borrow register */
	    pat = SvPVX(sv);
	    if (datumtype == 'b') {
		aint = len;
		for (len = 0; len < aint; len++) {
		    if (len & 7)		/*SUPPRESS 595*/
			bits >>= 1;
		    else
			bits = *s++;
		    *pat++ = '0' + (bits & 1);
		}
	    }
	    else {
		aint = len;
		for (len = 0; len < aint; len++) {
		    if (len & 7)
			bits <<= 1;
		    else
			bits = *s++;
		    *pat++ = '0' + ((bits & 128) != 0);
		}
	    }
	    *pat = '\0';
	    pat = aptr;			/* unborrow register */
	    XPUSHs(sv_2mortal(sv));
	    break;
	case 'H':
	case 'h':
	    if (pat[-1] == '*' || len > (strend - s) * 2)
		len = (strend - s) * 2;
	    sv = NEWSV(35, len + 1);
	    SvCUR_set(sv, len);
	    SvPOK_on(sv);
	    aptr = pat;			/* borrow register */
	    pat = SvPVX(sv);
	    if (datumtype == 'h') {
		aint = len;
		for (len = 0; len < aint; len++) {
		    if (len & 1)
			bits >>= 4;
		    else
			bits = *s++;
		    *pat++ = PL_hexdigit[bits & 15];
		}
	    }
	    else {
		aint = len;
		for (len = 0; len < aint; len++) {
		    if (len & 1)
			bits <<= 4;
		    else
			bits = *s++;
		    *pat++ = PL_hexdigit[(bits >> 4) & 15];
		}
	    }
	    *pat = '\0';
	    pat = aptr;			/* unborrow register */
	    XPUSHs(sv_2mortal(sv));
	    break;
	case 'c':
	    if (len > strend - s)
		len = strend - s;
	    if (checksum) {
		while (len-- > 0) {
		    aint = *s++;
		    if (aint >= 128)	/* fake up signed chars */
			aint -= 256;
		    culong += aint;
		}
	    }
	    else {
		EXTEND(SP, len);
		EXTEND_MORTAL(len);
		while (len-- > 0) {
		    aint = *s++;
		    if (aint >= 128)	/* fake up signed chars */
			aint -= 256;
		    sv = NEWSV(36, 0);
		    sv_setiv(sv, (IV)aint);
		    PUSHs(sv_2mortal(sv));
		}
	    }
	    break;
	case 'C':
	    if (len > strend - s)
		len = strend - s;
	    if (checksum) {
	      uchar_checksum:
		while (len-- > 0) {
		    auint = *s++ & 255;
		    culong += auint;
		}
	    }
	    else {
		EXTEND(SP, len);
		EXTEND_MORTAL(len);
		while (len-- > 0) {
		    auint = *s++ & 255;
		    sv = NEWSV(37, 0);
		    sv_setiv(sv, (IV)auint);
		    PUSHs(sv_2mortal(sv));
		}
	    }
	    break;
	case 's':
	    along = (strend - s) / SIZE16;
	    if (len > along)
		len = along;
	    if (checksum) {
		while (len-- > 0) {
		    COPY16(s, &ashort);
		    s += SIZE16;
		    culong += ashort;
		}
	    }
	    else {
		EXTEND(SP, len);
		EXTEND_MORTAL(len);
		while (len-- > 0) {
		    COPY16(s, &ashort);
		    s += SIZE16;
		    sv = NEWSV(38, 0);
		    sv_setiv(sv, (IV)ashort);
		    PUSHs(sv_2mortal(sv));
		}
	    }
	    break;
	case 'v':
	case 'n':
	case 'S':
	    along = (strend - s) / SIZE16;
	    if (len > along)
		len = along;
	    if (checksum) {
		while (len-- > 0) {
		    COPY16(s, &aushort);
		    s += SIZE16;
#ifdef HAS_NTOHS
		    if (datumtype == 'n')
			aushort = PerlSock_ntohs(aushort);
#endif
#ifdef HAS_VTOHS
		    if (datumtype == 'v')
			aushort = vtohs(aushort);
#endif
		    culong += aushort;
		}
	    }
	    else {
		EXTEND(SP, len);
		EXTEND_MORTAL(len);
		while (len-- > 0) {
		    COPY16(s, &aushort);
		    s += SIZE16;
		    sv = NEWSV(39, 0);
#ifdef HAS_NTOHS
		    if (datumtype == 'n')
			aushort = PerlSock_ntohs(aushort);
#endif
#ifdef HAS_VTOHS
		    if (datumtype == 'v')
			aushort = vtohs(aushort);
#endif
		    sv_setiv(sv, (IV)aushort);
		    PUSHs(sv_2mortal(sv));
		}
	    }
	    break;
	case 'i':
	    along = (strend - s) / sizeof(int);
	    if (len > along)
		len = along;
	    if (checksum) {
		while (len-- > 0) {
		    Copy(s, &aint, 1, int);
		    s += sizeof(int);
		    if (checksum > 32)
			cdouble += (double)aint;
		    else
			culong += aint;
		}
	    }
	    else {
		EXTEND(SP, len);
		EXTEND_MORTAL(len);
		while (len-- > 0) {
		    Copy(s, &aint, 1, int);
		    s += sizeof(int);
		    sv = NEWSV(40, 0);
#ifdef __osf__
                    /* Without the dummy below unpack("i", pack("i",-1))
                     * return 0xFFffFFff instead of -1 for Digital Unix V4.0
                     * cc with optimization turned on */
                    (aint) ?
		    	sv_setiv(sv, (IV)aint) :
#endif
		    sv_setiv(sv, (IV)aint);
		    PUSHs(sv_2mortal(sv));
		}
	    }
	    break;
	case 'I':
	    along = (strend - s) / sizeof(unsigned int);
	    if (len > along)
		len = along;
	    if (checksum) {
		while (len-- > 0) {
		    Copy(s, &auint, 1, unsigned int);
		    s += sizeof(unsigned int);
		    if (checksum > 32)
			cdouble += (double)auint;
		    else
			culong += auint;
		}
	    }
	    else {
		EXTEND(SP, len);
		EXTEND_MORTAL(len);
		while (len-- > 0) {
		    Copy(s, &auint, 1, unsigned int);
		    s += sizeof(unsigned int);
		    sv = NEWSV(41, 0);
		    sv_setuv(sv, (UV)auint);
		    PUSHs(sv_2mortal(sv));
		}
	    }
	    break;
	case 'l':
	    along = (strend - s) / SIZE32;
	    if (len > along)
		len = along;
	    if (checksum) {
		while (len-- > 0) {
		    COPY32(s, &along);
		    s += SIZE32;
		    if (checksum > 32)
			cdouble += (double)along;
		    else
			culong += along;
		}
	    }
	    else {
		EXTEND(SP, len);
		EXTEND_MORTAL(len);
		while (len-- > 0) {
		    COPY32(s, &along);
		    s += SIZE32;
		    sv = NEWSV(42, 0);
		    sv_setiv(sv, (IV)along);
		    PUSHs(sv_2mortal(sv));
		}
	    }
	    break;
	case 'V':
	case 'N':
	case 'L':
	    along = (strend - s) / SIZE32;
	    if (len > along)
		len = along;
	    if (checksum) {
		while (len-- > 0) {
		    COPY32(s, &aulong);
		    s += SIZE32;
#ifdef HAS_NTOHL
		    if (datumtype == 'N')
			aulong = PerlSock_ntohl(aulong);
#endif
#ifdef HAS_VTOHL
		    if (datumtype == 'V')
			aulong = vtohl(aulong);
#endif
		    if (checksum > 32)
			cdouble += (double)aulong;
		    else
			culong += aulong;
		}
	    }
	    else {
		EXTEND(SP, len);
		EXTEND_MORTAL(len);
		while (len-- > 0) {
		    COPY32(s, &aulong);
		    s += SIZE32;
#ifdef HAS_NTOHL
		    if (datumtype == 'N')
			aulong = PerlSock_ntohl(aulong);
#endif
#ifdef HAS_VTOHL
		    if (datumtype == 'V')
			aulong = vtohl(aulong);
#endif
		    sv = NEWSV(43, 0);
		    sv_setuv(sv, (UV)aulong);
		    PUSHs(sv_2mortal(sv));
		}
	    }
	    break;
	case 'p':
	    along = (strend - s) / sizeof(char*);
	    if (len > along)
		len = along;
	    EXTEND(SP, len);
	    EXTEND_MORTAL(len);
	    while (len-- > 0) {
		if (sizeof(char*) > strend - s)
		    break;
		else {
		    Copy(s, &aptr, 1, char*);
		    s += sizeof(char*);
		}
		sv = NEWSV(44, 0);
		if (aptr)
		    sv_setpv(sv, aptr);
		PUSHs(sv_2mortal(sv));
	    }
	    break;
	case 'w':
	    EXTEND(SP, len);
	    EXTEND_MORTAL(len);
	    {
		UV auv = 0;
		U32 bytes = 0;
		
		while ((len > 0) && (s < strend)) {
		    auv = (auv << 7) | (*s & 0x7f);
		    if (!(*s++ & 0x80)) {
			bytes = 0;
			sv = NEWSV(40, 0);
			sv_setuv(sv, auv);
			PUSHs(sv_2mortal(sv));
			len--;
			auv = 0;
		    }
		    else if (++bytes >= sizeof(UV)) {	/* promote to string */
			char *t;

			sv = newSVpvf("%.*Vu", (int)TYPE_DIGITS(UV), auv);
			while (s < strend) {
			    sv = mul128(sv, *s & 0x7f);
			    if (!(*s++ & 0x80)) {
				bytes = 0;
				break;
			    }
			}
			t = SvPV(sv, PL_na);
			while (*t == '0')
			    t++;
			sv_chop(sv, t);
			PUSHs(sv_2mortal(sv));
			len--;
			auv = 0;
		    }
		}
		if ((s >= strend) && bytes)
		    croak("Unterminated compressed integer");
	    }
	    break;
	case 'P':
	    EXTEND(SP, 1);
	    if (sizeof(char*) > strend - s)
		break;
	    else {
		Copy(s, &aptr, 1, char*);
		s += sizeof(char*);
	    }
	    sv = NEWSV(44, 0);
	    if (aptr)
		sv_setpvn(sv, aptr, len);
	    PUSHs(sv_2mortal(sv));
	    break;
#ifdef HAS_QUAD
	case 'q':
	    along = (strend - s) / sizeof(Quad_t);
	    if (len > along)
		len = along;
	    EXTEND(SP, len);
	    EXTEND_MORTAL(len);
	    while (len-- > 0) {
		if (s + sizeof(Quad_t) > strend)
		    aquad = 0;
		else {
		    Copy(s, &aquad, 1, Quad_t);
		    s += sizeof(Quad_t);
		}
		sv = NEWSV(42, 0);
		if (aquad >= IV_MIN && aquad <= IV_MAX)
		    sv_setiv(sv, (IV)aquad);
		else
		    sv_setnv(sv, (double)aquad);
		PUSHs(sv_2mortal(sv));
	    }
	    break;
	case 'Q':
	    along = (strend - s) / sizeof(Quad_t);
	    if (len > along)
		len = along;
	    EXTEND(SP, len);
	    EXTEND_MORTAL(len);
	    while (len-- > 0) {
		if (s + sizeof(unsigned Quad_t) > strend)
		    auquad = 0;
		else {
		    Copy(s, &auquad, 1, unsigned Quad_t);
		    s += sizeof(unsigned Quad_t);
		}
		sv = NEWSV(43, 0);
		if (auquad <= UV_MAX)
		    sv_setuv(sv, (UV)auquad);
		else
		    sv_setnv(sv, (double)auquad);
		PUSHs(sv_2mortal(sv));
	    }
	    break;
#endif
	/* float and double added gnb@melba.bby.oz.au 22/11/89 */
	case 'f':
	case 'F':
	    along = (strend - s) / sizeof(float);
	    if (len > along)
		len = along;
	    if (checksum) {
		while (len-- > 0) {
		    Copy(s, &afloat, 1, float);
		    s += sizeof(float);
		    cdouble += afloat;
		}
	    }
	    else {
		EXTEND(SP, len);
		EXTEND_MORTAL(len);
		while (len-- > 0) {
		    Copy(s, &afloat, 1, float);
		    s += sizeof(float);
		    sv = NEWSV(47, 0);
		    sv_setnv(sv, (double)afloat);
		    PUSHs(sv_2mortal(sv));
		}
	    }
	    break;
	case 'd':
	case 'D':
	    along = (strend - s) / sizeof(double);
	    if (len > along)
		len = along;
	    if (checksum) {
		while (len-- > 0) {
		    Copy(s, &adouble, 1, double);
		    s += sizeof(double);
		    cdouble += adouble;
		}
	    }
	    else {
		EXTEND(SP, len);
		EXTEND_MORTAL(len);
		while (len-- > 0) {
		    Copy(s, &adouble, 1, double);
		    s += sizeof(double);
		    sv = NEWSV(48, 0);
		    sv_setnv(sv, (double)adouble);
		    PUSHs(sv_2mortal(sv));
		}
	    }
	    break;
	case 'u':
	    /* MKS:
	     * Initialise the decode mapping.  By using a table driven
             * algorithm, the code will be character-set independent
             * (and just as fast as doing character arithmetic)
             */
            if (uudmap['M'] == 0) {
                int i;
 
                for (i = 0; i < sizeof(uuemap); i += 1)
                    uudmap[uuemap[i]] = i;
                /*
                 * Because ' ' and '`' map to the same value,
                 * we need to decode them both the same.
                 */
                uudmap[' '] = 0;
            }

	    along = (strend - s) * 3 / 4;
	    sv = NEWSV(42, along);
	    if (along)
		SvPOK_on(sv);
	    while (s < strend && *s > ' ' && ISUUCHAR(*s)) {
		I32 a, b, c, d;
		char hunk[4];

		hunk[3] = '\0';
		len = (*s++ - ' ') & 077;
		while (len > 0) {
		    if (s < strend && ISUUCHAR(*s))
			a = uudmap[*s++] & 077;
 		    else
 			a = 0;
		    if (s < strend && ISUUCHAR(*s))
			b = uudmap[*s++] & 077;
 		    else
 			b = 0;
		    if (s < strend && ISUUCHAR(*s))
			c = uudmap[*s++] & 077;
 		    else
 			c = 0;
		    if (s < strend && ISUUCHAR(*s))
			d = uudmap[*s++] & 077;
		    else
			d = 0;
		    hunk[0] = (a << 2) | (b >> 4);
		    hunk[1] = (b << 4) | (c >> 2);
		    hunk[2] = (c << 6) | d;
		    sv_catpvn(sv, hunk, (len > 3) ? 3 : len);
		    len -= 3;
		}
		if (*s == '\n')
		    s++;
		else if (s[1] == '\n')		/* possible checksum byte */
		    s += 2;
	    }
	    XPUSHs(sv_2mortal(sv));
	    break;
	}
	if (checksum) {
	    sv = NEWSV(42, 0);
	    if (strchr("fFdD", datumtype) ||
	      (checksum > 32 && strchr("iIlLN", datumtype)) ) {
		double trouble;

		adouble = 1.0;
		while (checksum >= 16) {
		    checksum -= 16;
		    adouble *= 65536.0;
		}
		while (checksum >= 4) {
		    checksum -= 4;
		    adouble *= 16.0;
		}
		while (checksum--)
		    adouble *= 2.0;
		along = (1 << checksum) - 1;
		while (cdouble < 0.0)
		    cdouble += adouble;
		cdouble = modf(cdouble / adouble, &trouble) * adouble;
		sv_setnv(sv, cdouble);
	    }
	    else {
		if (checksum < 32) {
		    aulong = (1 << checksum) - 1;
		    culong &= aulong;
		}
		sv_setuv(sv, (UV)culong);
	    }
	    XPUSHs(sv_2mortal(sv));
	    checksum = 0;
	}
    }
    if (SP == oldsp && gimme == G_SCALAR)
	PUSHs(&PL_sv_undef);
    RETURN;
}

STATIC void
doencodes(register SV *sv, register char *s, register I32 len)
{
    char hunk[5];

    *hunk = uuemap[len];
    sv_catpvn(sv, hunk, 1);
    hunk[4] = '\0';
    while (len > 2) {
	hunk[0] = uuemap[(077 & (*s >> 2))];
	hunk[1] = uuemap[(077 & (((*s << 4) & 060) | ((s[1] >> 4) & 017)))];
	hunk[2] = uuemap[(077 & (((s[1] << 2) & 074) | ((s[2] >> 6) & 03)))];
	hunk[3] = uuemap[(077 & (s[2] & 077))];
	sv_catpvn(sv, hunk, 4);
	s += 3;
	len -= 3;
    }
    if (len > 0) {
	char r = (len > 1 ? s[1] : '\0');
	hunk[0] = uuemap[(077 & (*s >> 2))];
	hunk[1] = uuemap[(077 & (((*s << 4) & 060) | ((r >> 4) & 017)))];
	hunk[2] = uuemap[(077 & ((r << 2) & 074))];
	hunk[3] = uuemap[0];
	sv_catpvn(sv, hunk, 4);
    }
    sv_catpvn(sv, "\n", 1);
}

STATIC SV      *
is_an_int(char *s, STRLEN l)
{
  SV             *result = newSVpv("", l);
  char           *result_c = SvPV(result, PL_na);	/* convenience */
  char           *out = result_c;
  bool            skip = 1;
  bool            ignore = 0;

  while (*s) {
    switch (*s) {
    case ' ':
      break;
    case '+':
      if (!skip) {
	SvREFCNT_dec(result);
	return (NULL);
      }
      break;
    case '0':
    case '1':
    case '2':
    case '3':
    case '4':
    case '5':
    case '6':
    case '7':
    case '8':
    case '9':
      skip = 0;
      if (!ignore) {
	*(out++) = *s;
      }
      break;
    case '.':
      ignore = 1;
      break;
    default:
      SvREFCNT_dec(result);
      return (NULL);
    }
    s++;
  }
  *(out++) = '\0';
  SvCUR_set(result, out - result_c);
  return (result);
}

STATIC int
div128(SV *pnum, bool *done)
                          		    /* must be '\0' terminated */

{
  STRLEN          len;
  char           *s = SvPV(pnum, len);
  int             m = 0;
  int             r = 0;
  char           *t = s;

  *done = 1;
  while (*t) {
    int             i;

    i = m * 10 + (*t - '0');
    m = i & 0x7F;
    r = (i >> 7);		/* r < 10 */
    if (r) {
      *done = 0;
    }
    *(t++) = '0' + r;
  }
  *(t++) = '\0';
  SvCUR_set(pnum, (STRLEN) (t - s));
  return (m);
}


PP(pp_pack)
{
    djSP; dMARK; dORIGMARK; dTARGET;
    register SV *cat = TARG;
    register I32 items;
    STRLEN fromlen;
    register char *pat = SvPVx(*++MARK, fromlen);
    register char *patend = pat + fromlen;
    register I32 len;
    I32 datumtype;
    SV *fromstr;
    /*SUPPRESS 442*/
    static char null10[] = {0,0,0,0,0,0,0,0,0,0};
    static char *space10 = "          ";

    /* These must not be in registers: */
    char achar;
    I16 ashort;
    int aint;
    unsigned int auint;
    I32 along;
    U32 aulong;
#ifdef HAS_QUAD
    Quad_t aquad;
    unsigned Quad_t auquad;
#endif
    char *aptr;
    float afloat;
    double adouble;
    int commas = 0;

    items = SP - MARK;
    MARK++;
    sv_setpvn(cat, "", 0);
    while (pat < patend) {
#define NEXTFROM (items-- > 0 ? *MARK++ : &PL_sv_no)
	datumtype = *pat++ & 0xFF;
	if (isSPACE(datumtype))
	    continue;
	if (*pat == '*') {
	    len = strchr("@Xxu", datumtype) ? 0 : items;
	    pat++;
	}
	else if (isDIGIT(*pat)) {
	    len = *pat++ - '0';
	    while (isDIGIT(*pat))
		len = (len * 10) + (*pat++ - '0');
	}
	else
	    len = 1;
	switch(datumtype) {
	default:
	    croak("Invalid type in pack: '%c'", (int)datumtype);
	case ',': /* grandfather in commas but with a warning */
	    if (commas++ == 0 && PL_dowarn)
		warn("Invalid type in pack: '%c'", (int)datumtype);
	    break;
	case '%':
	    DIE("%% may only be used in unpack");
	case '@':
	    len -= SvCUR(cat);
	    if (len > 0)
		goto grow;
	    len = -len;
	    if (len > 0)
		goto shrink;
	    break;
	case 'X':
	  shrink:
	    if (SvCUR(cat) < len)
		DIE("X outside of string");
	    SvCUR(cat) -= len;
	    *SvEND(cat) = '\0';
	    break;
	case 'x':
	  grow:
	    while (len >= 10) {
		sv_catpvn(cat, null10, 10);
		len -= 10;
	    }
	    sv_catpvn(cat, null10, len);
	    break;
	case 'A':
	case 'a':
	    fromstr = NEXTFROM;
	    aptr = SvPV(fromstr, fromlen);
	    if (pat[-1] == '*')
		len = fromlen;
	    if (fromlen > len)
		sv_catpvn(cat, aptr, len);
	    else {
		sv_catpvn(cat, aptr, fromlen);
		len -= fromlen;
		if (datumtype == 'A') {
		    while (len >= 10) {
			sv_catpvn(cat, space10, 10);
			len -= 10;
		    }
		    sv_catpvn(cat, space10, len);
		}
		else {
		    while (len >= 10) {
			sv_catpvn(cat, null10, 10);
			len -= 10;
		    }
		    sv_catpvn(cat, null10, len);
		}
	    }
	    break;
	case 'B':
	case 'b':
	    {
		char *savepat = pat;
		I32 saveitems;

		fromstr = NEXTFROM;
		saveitems = items;
		aptr = SvPV(fromstr, fromlen);
		if (pat[-1] == '*')
		    len = fromlen;
		pat = aptr;
		aint = SvCUR(cat);
		SvCUR(cat) += (len+7)/8;
		SvGROW(cat, SvCUR(cat) + 1);
		aptr = SvPVX(cat) + aint;
		if (len > fromlen)
		    len = fromlen;
		aint = len;
		items = 0;
		if (datumtype == 'B') {
		    for (len = 0; len++ < aint;) {
			items |= *pat++ & 1;
			if (len & 7)
			    items <<= 1;
			else {
			    *aptr++ = items & 0xff;
			    items = 0;
			}
		    }
		}
		else {
		    for (len = 0; len++ < aint;) {
			if (*pat++ & 1)
			    items |= 128;
			if (len & 7)
			    items >>= 1;
			else {
			    *aptr++ = items & 0xff;
			    items = 0;
			}
		    }
		}
		if (aint & 7) {
		    if (datumtype == 'B')
			items <<= 7 - (aint & 7);
		    else
			items >>= 7 - (aint & 7);
		    *aptr++ = items & 0xff;
		}
		pat = SvPVX(cat) + SvCUR(cat);
		while (aptr <= pat)
		    *aptr++ = '\0';

		pat = savepat;
		items = saveitems;
	    }
	    break;
	case 'H':
	case 'h':
	    {
		char *savepat = pat;
		I32 saveitems;

		fromstr = NEXTFROM;
		saveitems = items;
		aptr = SvPV(fromstr, fromlen);
		if (pat[-1] == '*')
		    len = fromlen;
		pat = aptr;
		aint = SvCUR(cat);
		SvCUR(cat) += (len+1)/2;
		SvGROW(cat, SvCUR(cat) + 1);
		aptr = SvPVX(cat) + aint;
		if (len > fromlen)
		    len = fromlen;
		aint = len;
		items = 0;
		if (datumtype == 'H') {
		    for (len = 0; len++ < aint;) {
			if (isALPHA(*pat))
			    items |= ((*pat++ & 15) + 9) & 15;
			else
			    items |= *pat++ & 15;
			if (len & 1)
			    items <<= 4;
			else {
			    *aptr++ = items & 0xff;
			    items = 0;
			}
		    }
		}
		else {
		    for (len = 0; len++ < aint;) {
			if (isALPHA(*pat))
			    items |= (((*pat++ & 15) + 9) & 15) << 4;
			else
			    items |= (*pat++ & 15) << 4;
			if (len & 1)
			    items >>= 4;
			else {
			    *aptr++ = items & 0xff;
			    items = 0;
			}
		    }
		}
		if (aint & 1)
		    *aptr++ = items & 0xff;
		pat = SvPVX(cat) + SvCUR(cat);
		while (aptr <= pat)
		    *aptr++ = '\0';

		pat = savepat;
		items = saveitems;
	    }
	    break;
	case 'C':
	case 'c':
	    while (len-- > 0) {
		fromstr = NEXTFROM;
		aint = SvIV(fromstr);
		achar = aint;
		sv_catpvn(cat, &achar, sizeof(char));
	    }
	    break;
	/* Float and double added by gnb@melba.bby.oz.au  22/11/89 */
	case 'f':
	case 'F':
	    while (len-- > 0) {
		fromstr = NEXTFROM;
		afloat = (float)SvNV(fromstr);
		sv_catpvn(cat, (char *)&afloat, sizeof (float));
	    }
	    break;
	case 'd':
	case 'D':
	    while (len-- > 0) {
		fromstr = NEXTFROM;
		adouble = (double)SvNV(fromstr);
		sv_catpvn(cat, (char *)&adouble, sizeof (double));
	    }
	    break;
	case 'n':
	    while (len-- > 0) {
		fromstr = NEXTFROM;
		ashort = (I16)SvIV(fromstr);
#ifdef HAS_HTONS
		ashort = PerlSock_htons(ashort);
#endif
		CAT16(cat, &ashort);
	    }
	    break;
	case 'v':
	    while (len-- > 0) {
		fromstr = NEXTFROM;
		ashort = (I16)SvIV(fromstr);
#ifdef HAS_HTOVS
		ashort = htovs(ashort);
#endif
		CAT16(cat, &ashort);
	    }
	    break;
	case 'S':
	case 's':
	    while (len-- > 0) {
		fromstr = NEXTFROM;
		ashort = (I16)SvIV(fromstr);
		CAT16(cat, &ashort);
	    }
	    break;
	case 'I':
	    while (len-- > 0) {
		fromstr = NEXTFROM;
		auint = SvUV(fromstr);
		sv_catpvn(cat, (char*)&auint, sizeof(unsigned int));
	    }
	    break;
	case 'w':
            while (len-- > 0) {
		fromstr = NEXTFROM;
		adouble = floor(SvNV(fromstr));

		if (adouble < 0)
		    croak("Cannot compress negative numbers");

		if (
#ifdef BW_BITS
		    adouble <= BW_MASK
#else
#ifdef CXUX_BROKEN_CONSTANT_CONVERT
		    adouble <= UV_MAX_cxux
#else
		    adouble <= UV_MAX
#endif
#endif
		    )
		{
		    char   buf[1 + sizeof(UV)];
		    char  *in = buf + sizeof(buf);
		    UV     auv = U_V(adouble);;

		    do {
			*--in = (auv & 0x7f) | 0x80;
			auv >>= 7;
		    } while (auv);
		    buf[sizeof(buf) - 1] &= 0x7f; /* clear continue bit */
		    sv_catpvn(cat, in, (buf + sizeof(buf)) - in);
		}
		else if (SvPOKp(fromstr)) {  /* decimal string arithmetics */
		    char           *from, *result, *in;
		    SV             *norm;
		    STRLEN          len;
		    bool            done;

		    /* Copy string and check for compliance */
		    from = SvPV(fromstr, len);
		    if ((norm = is_an_int(from, len)) == NULL)
			croak("can compress only unsigned integer");

		    New('w', result, len, char);
		    in = result + len;
		    done = FALSE;
		    while (!done)
			*--in = div128(norm, &done) | 0x80;
		    result[len - 1] &= 0x7F; /* clear continue bit */
		    sv_catpvn(cat, in, (result + len) - in);
		    Safefree(result);
		    SvREFCNT_dec(norm);	/* free norm */
                }
		else if (SvNOKp(fromstr)) {
		    char   buf[sizeof(double) * 2];	/* 8/7 <= 2 */
		    char  *in = buf + sizeof(buf);

		    do {
			double next = floor(adouble / 128);
			*--in = (unsigned char)(adouble - (next * 128)) | 0x80;
			if (--in < buf)  /* this cannot happen ;-) */
			    croak ("Cannot compress integer");
			adouble = next;
		    } while (adouble > 0);
		    buf[sizeof(buf) - 1] &= 0x7f; /* clear continue bit */
		    sv_catpvn(cat, in, (buf + sizeof(buf)) - in);
		}
		else
		    croak("Cannot compress non integer");
	    }
            break;
	case 'i':
	    while (len-- > 0) {
		fromstr = NEXTFROM;
		aint = SvIV(fromstr);
		sv_catpvn(cat, (char*)&aint, sizeof(int));
	    }
	    break;
	case 'N':
	    while (len-- > 0) {
		fromstr = NEXTFROM;
		aulong = SvUV(fromstr);
#ifdef HAS_HTONL
		aulong = PerlSock_htonl(aulong);
#endif
		CAT32(cat, &aulong);
	    }
	    break;
	case 'V':
	    while (len-- > 0) {
		fromstr = NEXTFROM;
		aulong = SvUV(fromstr);
#ifdef HAS_HTOVL
		aulong = htovl(aulong);
#endif
		CAT32(cat, &aulong);
	    }
	    break;
	case 'L':
	    while (len-- > 0) {
		fromstr = NEXTFROM;
		aulong = SvUV(fromstr);
		CAT32(cat, &aulong);
	    }
	    break;
	case 'l':
	    while (len-- > 0) {
		fromstr = NEXTFROM;
		along = SvIV(fromstr);
		CAT32(cat, &along);
	    }
	    break;
#ifdef HAS_QUAD
	case 'Q':
	    while (len-- > 0) {
		fromstr = NEXTFROM;
		auquad = (unsigned Quad_t)SvIV(fromstr);
		sv_catpvn(cat, (char*)&auquad, sizeof(unsigned Quad_t));
	    }
	    break;
	case 'q':
	    while (len-- > 0) {
		fromstr = NEXTFROM;
		aquad = (Quad_t)SvIV(fromstr);
		sv_catpvn(cat, (char*)&aquad, sizeof(Quad_t));
	    }
	    break;
#endif /* HAS_QUAD */
	case 'P':
	    len = 1;		/* assume SV is correct length */
	    /* FALL THROUGH */
	case 'p':
	    while (len-- > 0) {
		fromstr = NEXTFROM;
		if (fromstr == &PL_sv_undef)
		    aptr = NULL;
		else {
		    /* XXX better yet, could spirit away the string to
		     * a safe spot and hang on to it until the result
		     * of pack() (and all copies of the result) are
		     * gone.
		     */
		    if (PL_dowarn && (SvTEMP(fromstr) || SvPADTMP(fromstr)))
			warn("Attempt to pack pointer to temporary value");
		    if (SvPOK(fromstr) || SvNIOK(fromstr))
			aptr = SvPV(fromstr,PL_na);
		    else
			aptr = SvPV_force(fromstr,PL_na);
		}
		sv_catpvn(cat, (char*)&aptr, sizeof(char*));
	    }
	    break;
	case 'u':
	    fromstr = NEXTFROM;
	    aptr = SvPV(fromstr, fromlen);
	    SvGROW(cat, fromlen * 4 / 3);
	    if (len <= 1)
		len = 45;
	    else
		len = len / 3 * 3;
	    while (fromlen > 0) {
		I32 todo;

		if (fromlen > len)
		    todo = len;
		else
		    todo = fromlen;
		doencodes(cat, aptr, todo);
		fromlen -= todo;
		aptr += todo;
	    }
	    break;
	}
    }
    SvSETMAGIC(cat);
    SP = ORIGMARK;
    PUSHs(cat);
    RETURN;
}
#undef NEXTFROM


PP(pp_split)
{
    djSP; dTARG;
    AV *ary;
    register I32 limit = POPi;			/* note, negative is forever */
    SV *sv = POPs;
    STRLEN len;
    register char *s = SvPV(sv, len);
    char *strend = s + len;
    register PMOP *pm;
    register REGEXP *rx;
    register SV *dstr;
    register char *m;
    I32 iters = 0;
    I32 maxiters = (strend - s) + 10;
    I32 i;
    char *orig;
    I32 origlimit = limit;
    I32 realarray = 0;
    I32 base;
    AV *oldstack = PL_curstack;
    I32 gimme = GIMME_V;
    I32 oldsave = PL_savestack_ix;
    I32 make_mortal = 1;
    MAGIC *mg = (MAGIC *) NULL;

#ifdef DEBUGGING
    Copy(&LvTARGOFF(POPs), &pm, 1, PMOP*);
#else
    pm = (PMOP*)POPs;
#endif
    if (!pm || !s)
	DIE("panic: do_split");
    rx = pm->op_pmregexp;

    TAINT_IF((pm->op_pmflags & PMf_LOCALE) &&
	     (pm->op_pmflags & (PMf_WHITE | PMf_SKIPWHITE)));

    if (pm->op_pmreplroot)
	ary = GvAVn((GV*)pm->op_pmreplroot);
    else if (gimme != G_ARRAY)
#ifdef USE_THREADS
	ary = (AV*)PL_curpad[0];
#else
	ary = GvAVn(PL_defgv);
#endif /* USE_THREADS */
    else
	ary = Nullav;
    if (ary && (gimme != G_ARRAY || (pm->op_pmflags & PMf_ONCE))) {
	realarray = 1;
	PUTBACK;
	av_extend(ary,0);
	av_clear(ary);
	SPAGAIN;
	if (SvRMAGICAL(ary) && (mg = mg_find((SV *) ary, 'P'))) {
	    PUSHMARK(SP);
	    XPUSHs(mg->mg_obj);
	}
	else {
	    if (!AvREAL(ary)) {
		AvREAL_on(ary);
		for (i = AvFILLp(ary); i >= 0; i--)
		    AvARRAY(ary)[i] = &PL_sv_undef;	/* don't free mere refs */
	    }
	    /* temporarily switch stacks */
	    SWITCHSTACK(PL_curstack, ary);
	    make_mortal = 0;
	}
    }
    base = SP - PL_stack_base;
    orig = s;
    if (pm->op_pmflags & PMf_SKIPWHITE) {
	if (pm->op_pmflags & PMf_LOCALE) {
	    while (isSPACE_LC(*s))
		s++;
	}
	else {
	    while (isSPACE(*s))
		s++;
	}
    }
    if (pm->op_pmflags & (PMf_MULTILINE|PMf_SINGLELINE)) {
	SAVEINT(PL_multiline);
	PL_multiline = pm->op_pmflags & PMf_MULTILINE;
    }

    if (!limit)
	limit = maxiters + 2;
    if (pm->op_pmflags & PMf_WHITE) {
	while (--limit) {
	    m = s;
	    while (m < strend &&
		   !((pm->op_pmflags & PMf_LOCALE)
		     ? isSPACE_LC(*m) : isSPACE(*m)))
		++m;
	    if (m >= strend)
		break;

	    dstr = NEWSV(30, m-s);
	    sv_setpvn(dstr, s, m-s);
	    if (make_mortal)
		sv_2mortal(dstr);
	    XPUSHs(dstr);

	    s = m + 1;
	    while (s < strend &&
		   ((pm->op_pmflags & PMf_LOCALE)
		    ? isSPACE_LC(*s) : isSPACE(*s)))
		++s;
	}
    }
    else if (strEQ("^", rx->precomp)) {
	while (--limit) {
	    /*SUPPRESS 530*/
	    for (m = s; m < strend && *m != '\n'; m++) ;
	    m++;
	    if (m >= strend)
		break;
	    dstr = NEWSV(30, m-s);
	    sv_setpvn(dstr, s, m-s);
	    if (make_mortal)
		sv_2mortal(dstr);
	    XPUSHs(dstr);
	    s = m;
	}
    }
    else if (rx->check_substr && !rx->nparens
	     && (rx->reganch & ROPT_CHECK_ALL)
	     && !(rx->reganch & ROPT_ANCH)) {
	i = SvCUR(rx->check_substr);
	if (i == 1 && !SvTAIL(rx->check_substr)) {
	    i = *SvPVX(rx->check_substr);
	    while (--limit) {
		/*SUPPRESS 530*/
		for (m = s; m < strend && *m != i; m++) ;
		if (m >= strend)
		    break;
		dstr = NEWSV(30, m-s);
		sv_setpvn(dstr, s, m-s);
		if (make_mortal)
		    sv_2mortal(dstr);
		XPUSHs(dstr);
		s = m + 1;
	    }
	}
	else {
#ifndef lint
	    while (s < strend && --limit &&
	      (m=fbm_instr((unsigned char*)s, (unsigned char*)strend,
		    rx->check_substr, 0)) )
#endif
	    {
		dstr = NEWSV(31, m-s);
		sv_setpvn(dstr, s, m-s);
		if (make_mortal)
		    sv_2mortal(dstr);
		XPUSHs(dstr);
		s = m + i;
	    }
	}
    }
    else {
	maxiters += (strend - s) * rx->nparens;
	while (s < strend && --limit &&
	       CALLREGEXEC(rx, s, strend, orig, 1, Nullsv, NULL, 0))
	{
	    TAINT_IF(RX_MATCH_TAINTED(rx));
	    if (rx->subbase
	      && rx->subbase != orig) {
		m = s;
		s = orig;
		orig = rx->subbase;
		s = orig + (m - s);
		strend = s + (strend - m);
	    }
	    m = rx->startp[0];
	    dstr = NEWSV(32, m-s);
	    sv_setpvn(dstr, s, m-s);
	    if (make_mortal)
		sv_2mortal(dstr);
	    XPUSHs(dstr);
	    if (rx->nparens) {
		for (i = 1; i <= rx->nparens; i++) {
		    s = rx->startp[i];
		    m = rx->endp[i];
		    if (m && s) {
			dstr = NEWSV(33, m-s);
			sv_setpvn(dstr, s, m-s);
		    }
		    else
			dstr = NEWSV(33, 0);
		    if (make_mortal)
			sv_2mortal(dstr);
		    XPUSHs(dstr);
		}
	    }
	    s = rx->endp[0];
	}
    }

    LEAVE_SCOPE(oldsave);
    iters = (SP - PL_stack_base) - base;
    if (iters > maxiters)
	DIE("Split loop");

    /* keep field after final delim? */
    if (s < strend || (iters && origlimit)) {
	dstr = NEWSV(34, strend-s);
	sv_setpvn(dstr, s, strend-s);
	if (make_mortal)
	    sv_2mortal(dstr);
	XPUSHs(dstr);
	iters++;
    }
    else if (!origlimit) {
	while (iters > 0 && (!TOPs || !SvANY(TOPs) || SvCUR(TOPs) == 0))
	    iters--, SP--;
    }

    if (realarray) {
	if (!mg) {
	    SWITCHSTACK(ary, oldstack);
	    if (SvSMAGICAL(ary)) {
		PUTBACK;
		mg_set((SV*)ary);
		SPAGAIN;
	    }
	    if (gimme == G_ARRAY) {
		EXTEND(SP, iters);
		Copy(AvARRAY(ary), SP + 1, iters, SV*);
		SP += iters;
		RETURN;
	    }
	}
	else {
	    PUTBACK;
	    ENTER;
	    perl_call_method("PUSH",G_SCALAR|G_DISCARD);
	    LEAVE;
	    SPAGAIN;
	    if (gimme == G_ARRAY) {
		/* EXTEND should not be needed - we just popped them */
		EXTEND(SP, iters);
		for (i=0; i < iters; i++) {
		    SV **svp = av_fetch(ary, i, FALSE);
		    PUSHs((svp) ? *svp : &PL_sv_undef);
		}
		RETURN;
	    }
	}
    }
    else {
	if (gimme == G_ARRAY)
	    RETURN;
    }
    if (iters || !pm->op_pmreplroot) {
	GETTARGET;
	PUSHi(iters);
	RETURN;
    }
    RETPUSHUNDEF;
}

#ifdef USE_THREADS
void
unlock_condpair(void *svv)
{
    dTHR;
    MAGIC *mg = mg_find((SV*)svv, 'm');

    if (!mg)
	croak("panic: unlock_condpair unlocking non-mutex");
    MUTEX_LOCK(MgMUTEXP(mg));
    if (MgOWNER(mg) != thr)
	croak("panic: unlock_condpair unlocking mutex that we don't own");
    MgOWNER(mg) = 0;
    COND_SIGNAL(MgOWNERCONDP(mg));
    DEBUG_S(PerlIO_printf(PerlIO_stderr(), "0x%lx: unlock 0x%lx\n",
			  (unsigned long)thr, (unsigned long)svv);)
    MUTEX_UNLOCK(MgMUTEXP(mg));
}
#endif /* USE_THREADS */

PP(pp_lock)
{
    djSP;
    dTOPss;
    SV *retsv = sv;
#ifdef USE_THREADS
    MAGIC *mg;

    if (SvROK(sv))
	sv = SvRV(sv);

    mg = condpair_magic(sv);
    MUTEX_LOCK(MgMUTEXP(mg));
    if (MgOWNER(mg) == thr)
	MUTEX_UNLOCK(MgMUTEXP(mg));
    else {
	while (MgOWNER(mg))
	    COND_WAIT(MgOWNERCONDP(mg), MgMUTEXP(mg));
	MgOWNER(mg) = thr;
	DEBUG_S(PerlIO_printf(PerlIO_stderr(), "0x%lx: pp_lock lock 0x%lx\n",
			      (unsigned long)thr, (unsigned long)sv);)
	MUTEX_UNLOCK(MgMUTEXP(mg));
	SvREFCNT_inc(sv);	/* keep alive until magic_mutexfree */
	save_destructor(unlock_condpair, sv);
    }
#endif /* USE_THREADS */
    if (SvTYPE(retsv) == SVt_PVAV || SvTYPE(retsv) == SVt_PVHV
	|| SvTYPE(retsv) == SVt_PVCV) {
	retsv = refto(retsv);
    }
    SETs(retsv);
    RETURN;
}

PP(pp_threadsv)
{
    djSP;
#ifdef USE_THREADS
    EXTEND(SP, 1);
    if (PL_op->op_private & OPpLVAL_INTRO)
	PUSHs(*save_threadsv(PL_op->op_targ));
    else
	PUSHs(THREADSV(PL_op->op_targ));
    RETURN;
#else
    DIE("tried to access per-thread data in non-threaded perl");
#endif /* USE_THREADS */
}