Fix typo in B::Assembler.

[perl5.git] / ext / B / B / C.pm

#      C.pm
#
#      Copyright (c) 1996, 1997, 1998 Malcolm Beattie
#
#      You may distribute under the terms of either the GNU General Public
#      License or the Artistic License, as specified in the README file.
#
package B::C::Section;

our $VERSION = '1.04';

use B ();
use base B::Section;

sub new
{
 my $class = shift;
 my $o = $class->SUPER::new(@_);
 push @$o, { values => [] };
 return $o;
}

sub add
{
 my $section = shift;
 push(@{$section->[-1]{values}},@_);
}

sub index
{
 my $section = shift;
 return scalar(@{$section->[-1]{values}})-1;
}

sub output
{
 my ($section, $fh, $format) = @_;
 my $sym = $section->symtable || {};
 my $default = $section->default;
 my $i;
 foreach (@{$section->[-1]{values}})
  {
   s{(s\\_[0-9a-f]+)}{ exists($sym->{$1}) ? $sym->{$1} : $default; }ge;
   printf $fh $format, $_, $i;
   ++$i;
  }
}

package B::C::InitSection;

# avoid use vars
@B::C::InitSection::ISA = qw(B::C::Section);

sub new {
    my $class = shift;
    my $max_lines = 10000; #pop;
    my $section = $class->SUPER::new( @_ );

    $section->[-1]{evals} = [];
    $section->[-1]{chunks} = [];
    $section->[-1]{nosplit} = 0;
    $section->[-1]{current} = [];
    $section->[-1]{count} = 0;
    $section->[-1]{max_lines} = $max_lines;

    return $section;
}

sub split {
    my $section = shift;
    $section->[-1]{nosplit}--
      if $section->[-1]{nosplit} > 0;
}

sub no_split {
    shift->[-1]{nosplit}++;
}

sub inc_count {
    my $section = shift;

    $section->[-1]{count} += $_[0];
    # this is cheating
    $section->add();
}

sub add {
    my $section = shift->[-1];
    my $current = $section->{current};
    my $nosplit = $section->{nosplit};

    push @$current, @_;
    $section->{count} += scalar(@_);
    if( !$nosplit && $section->{count} >= $section->{max_lines} ) {
        push @{$section->{chunks}}, $current;
        $section->{current} = [];
        $section->{count} = 0;
    }
}

sub add_eval {
    my $section = shift;
    my @strings = @_;

    foreach my $i ( @strings ) {
        $i =~ s/\"/\\\"/g;
    }
    push @{$section->[-1]{evals}}, @strings;
}

sub output {
    my( $section, $fh, $format, $init_name ) = @_;
    my $sym = $section->symtable || {};
    my $default = $section->default;
    push @{$section->[-1]{chunks}}, $section->[-1]{current};

    my $name = "aaaa";
    foreach my $i ( @{$section->[-1]{chunks}} ) {
        print $fh <<"EOT";
static int perl_init_${name}()
{
	dTARG;
	dSP;
EOT
        foreach my $j ( @$i ) {
            $j =~ s{(s\\_[0-9a-f]+)}
                   { exists($sym->{$1}) ? $sym->{$1} : $default; }ge;
            print $fh "\t$j\n";
        }
        print $fh "\treturn 0;\n}\n";

        $section->SUPER::add( "perl_init_${name}();" );
        ++$name;
    }
    foreach my $i ( @{$section->[-1]{evals}} ) {
        $section->SUPER::add( sprintf q{eval_pv("%s",1);}, $i );
    }

    print $fh <<"EOT";
static int ${init_name}()
{
	dTARG;
	dSP;
EOT
    $section->SUPER::output( $fh, $format );
    print $fh "\treturn 0;\n}\n";
}


package B::C;
use Exporter ();
our %REGEXP;

{ # block necessary for caller to work
    my $caller = caller;
    if( $caller eq 'O' ) {
        require XSLoader;
        XSLoader::load( 'B::C' );
    }
}

@ISA = qw(Exporter);
@EXPORT_OK = qw(output_all output_boilerplate output_main mark_unused
		init_sections set_callback save_unused_subs objsym save_context);

use B qw(minus_c sv_undef walkoptree walksymtable main_root main_start peekop
	 class cstring cchar svref_2object compile_stats comppadlist hash
	 threadsv_names main_cv init_av end_av regex_padav opnumber amagic_generation
	 AVf_REAL HEf_SVKEY SVf_POK SVf_ROK CVf_CONST);
use B::Asmdata qw(@specialsv_name);

use FileHandle;
use Carp;
use strict;
use Config;

my $hv_index = 0;
my $gv_index = 0;
my $re_index = 0;
my $pv_index = 0;
my $cv_index = 0;
my $anonsub_index = 0;
my $initsub_index = 0;

my %symtable;
my %xsub;
my $warn_undefined_syms;
my $verbose;
my %unused_sub_packages;
my $use_xsloader;
my $nullop_count;
my $pv_copy_on_grow = 0;
my $optimize_ppaddr = 0;
my $optimize_warn_sv = 0;
my $use_perl_script_name = 0;
my $save_data_fh = 0;
my $save_sig = 0;
my ($debug_cops, $debug_av, $debug_cv, $debug_mg);
my $max_string_len;

my $ithreads = $Config{useithreads} eq 'define';

my @threadsv_names;
BEGIN {
    @threadsv_names = threadsv_names();
}

# Code sections
my ($init, $decl, $symsect, $binopsect, $condopsect, $copsect, 
    $padopsect, $listopsect, $logopsect, $loopsect, $opsect, $pmopsect,
    $pvopsect, $svopsect, $unopsect, $svsect, $xpvsect, $xpvavsect,
    $xpvhvsect, $xpvcvsect, $xpvivsect, $xpvnvsect, $xpvmgsect, $xpvlvsect,
    $xrvsect, $xpvbmsect, $xpviosect );
my @op_sections = \( $binopsect, $condopsect, $copsect, $padopsect, $listopsect,
                     $logopsect, $loopsect, $opsect, $pmopsect, $pvopsect, $svopsect,
                     $unopsect );

sub walk_and_save_optree;
my $saveoptree_callback = \&walk_and_save_optree;
sub set_callback { $saveoptree_callback = shift }
sub saveoptree { &$saveoptree_callback(@_) }

sub walk_and_save_optree {
    my ($name, $root, $start) = @_;
    walkoptree($root, "save");
    return objsym($start);
}

# Set the values for op_opt and op_static in each op.  The value of
# op_opt is irrelevant, and the value of op_static needs to be 1 to tell
# op_free that this is a statically defined op and that is shouldn't be
# freed.
my $op_os = "0, 1, 0";

# Look this up here so we can do just a number compare
# rather than looking up the name of every BASEOP in B::OP
my $OP_THREADSV = opnumber('threadsv');

sub savesym {
    my ($obj, $value) = @_;
    my $sym = sprintf("s\\_%x", $$obj);
    $symtable{$sym} = $value;
}

sub objsym {
    my $obj = shift;
    return $symtable{sprintf("s\\_%x", $$obj)};
}

sub getsym {
    my $sym = shift;
    my $value;

    return 0 if $sym eq "sym_0";	# special case
    $value = $symtable{$sym};
    if (defined($value)) {
	return $value;
    } else {
	warn "warning: undefined symbol $sym\n" if $warn_undefined_syms;
	return "UNUSED";
    }
}

sub savere {
    my $re = shift;
    my $sym = sprintf("re%d", $re_index++);
    $decl->add(sprintf("static char *$sym = %s;", cstring($re)));

    return ($sym,length(pack "a*",$re));
}

sub savepv {
    my $pv = pack "a*", shift;
    my $pvsym = 0;
    my $pvmax = 0;
    if ($pv_copy_on_grow) {
        $pvsym = sprintf("pv%d", $pv_index++);

        if( defined $max_string_len && length($pv) > $max_string_len ) {
            my $chars = join ', ', map { cchar $_ } split //, $pv;
            $decl->add(sprintf("static char %s[] = { %s };", $pvsym, $chars));
        }
        else {
	     my $cstring = cstring($pv);
            if ($cstring ne "0") { # sic
                $decl->add(sprintf("static char %s[] = %s;",
                                   $pvsym, $cstring));
	    }
        }
    } else {
	$pvmax = length(pack "a*",$pv) + 1;
    }
    return ($pvsym, $pvmax);
}

sub save_rv {
    my $sv = shift;
#    confess "Can't save RV: not ROK" unless $sv->FLAGS & SVf_ROK;
    my $rv = $sv->RV->save;

    $rv =~ s/^\(([AGHS]V|IO)\s*\*\)\s*(\&sv_list.*)$/$2/;

    return $rv;
}

# savesym, pvmax, len, pv
sub save_pv_or_rv {
    my $sv = shift;

    my $rok = $sv->FLAGS & SVf_ROK;
    my $pok = $sv->FLAGS & SVf_POK;
    my( $len, $pvmax, $savesym, $pv ) = ( 0, 0 );
    if( $rok ) {
       $savesym = '(char*)' . save_rv( $sv );
    }
    else {
       $pv = $pok ? (pack "a*", $sv->PV) : undef;
       $len = $pok ? length($pv) : 0;
       ($savesym, $pvmax) = $pok ? savepv($pv) : ( 'NULL', 0 );
    }

    return ( $savesym, $pvmax, $len, $pv );
}

# see also init_op_ppaddr below; initializes the ppaddt to the
# OpTYPE; init_op_ppaddr iterates over the ops and sets
# op_ppaddr to PL_ppaddr[op_ppaddr]; this avoids an explicit assignmente
# in perl_init ( ~10 bytes/op with GCC/i386 )
sub B::OP::fake_ppaddr {
    return $optimize_ppaddr ?
      sprintf("INT2PTR(void*,OP_%s)", uc( $_[0]->name ) ) :
      'NULL';
}

sub B::OP::save {
    my ($op, $level) = @_;
    my $sym = objsym($op);
    return $sym if defined $sym;
    my $type = $op->type;
    $nullop_count++ unless $type;
    if ($type == $OP_THREADSV) {
	# saves looking up ppaddr but it's a bit naughty to hard code this
	$init->add(sprintf("(void)find_threadsv(%s);",
			   cstring($threadsv_names[$op->targ])));
    }
    $opsect->add(sprintf("s\\_%x, s\\_%x, %s, %u, %u, $op_os, 0x%x, 0x%x",
			 ${$op->next}, ${$op->sibling}, $op->fake_ppaddr, $op->targ,
			 $type, $op->flags, $op->private));
    my $ix = $opsect->index;
    $init->add(sprintf("op_list[$ix].op_ppaddr = %s;", $op->ppaddr))
        unless $optimize_ppaddr;
    savesym($op, "&op_list[$ix]");
}

sub B::FAKEOP::new {
    my ($class, %objdata) = @_;
    bless \%objdata, $class;
}

sub B::FAKEOP::save {
    my ($op, $level) = @_;
    $opsect->add(sprintf("%s, %s, %s, %u, %u, $op_os, 0x%x, 0x%x",
			 $op->next, $op->sibling, $op->fake_ppaddr, $op->targ,
			 $op->type, $op->flags, $op->private));
    my $ix = $opsect->index;
    $init->add(sprintf("op_list[$ix].op_ppaddr = %s;", $op->ppaddr))
        unless $optimize_ppaddr;
    return "&op_list[$ix]";
}

sub B::FAKEOP::next { $_[0]->{"next"} || 0 }
sub B::FAKEOP::type { $_[0]->{type} || 0}
sub B::FAKEOP::sibling { $_[0]->{sibling} || 0 }
sub B::FAKEOP::ppaddr { $_[0]->{ppaddr} || 0 }
sub B::FAKEOP::targ { $_[0]->{targ} || 0 }
sub B::FAKEOP::flags { $_[0]->{flags} || 0 }
sub B::FAKEOP::private { $_[0]->{private} || 0 }

sub B::UNOP::save {
    my ($op, $level) = @_;
    my $sym = objsym($op);
    return $sym if defined $sym;
    $unopsect->add(sprintf("s\\_%x, s\\_%x, %s, %u, %u, $op_os, 0x%x, 0x%x, s\\_%x",
			   ${$op->next}, ${$op->sibling}, $op->fake_ppaddr,
			   $op->targ, $op->type, $op->flags,
			   $op->private, ${$op->first}));
    my $ix = $unopsect->index;
    $init->add(sprintf("unop_list[$ix].op_ppaddr = %s;", $op->ppaddr))
        unless $optimize_ppaddr;
    savesym($op, "(OP*)&unop_list[$ix]");
}

sub B::BINOP::save {
    my ($op, $level) = @_;
    my $sym = objsym($op);
    return $sym if defined $sym;
    $binopsect->add(sprintf("s\\_%x, s\\_%x, %s, %u, %u, $op_os, 0x%x, 0x%x, s\\_%x, s\\_%x",
			    ${$op->next}, ${$op->sibling}, $op->fake_ppaddr,
			    $op->targ, $op->type, $op->flags,
			    $op->private, ${$op->first}, ${$op->last}));
    my $ix = $binopsect->index;
    $init->add(sprintf("binop_list[$ix].op_ppaddr = %s;", $op->ppaddr))
        unless $optimize_ppaddr;
    savesym($op, "(OP*)&binop_list[$ix]");
}

sub B::LISTOP::save {
    my ($op, $level) = @_;
    my $sym = objsym($op);
    return $sym if defined $sym;
    $listopsect->add(sprintf("s\\_%x, s\\_%x, %s, %u, %u, $op_os, 0x%x, 0x%x, s\\_%x, s\\_%x",
			     ${$op->next}, ${$op->sibling}, $op->fake_ppaddr,
			     $op->targ, $op->type, $op->flags,
			     $op->private, ${$op->first}, ${$op->last}));
    my $ix = $listopsect->index;
    $init->add(sprintf("listop_list[$ix].op_ppaddr = %s;", $op->ppaddr))
        unless $optimize_ppaddr;
    savesym($op, "(OP*)&listop_list[$ix]");
}

sub B::LOGOP::save {
    my ($op, $level) = @_;
    my $sym = objsym($op);
    return $sym if defined $sym;
    $logopsect->add(sprintf("s\\_%x, s\\_%x, %s, %u, %u, $op_os, 0x%x, 0x%x, s\\_%x, s\\_%x",
			    ${$op->next}, ${$op->sibling}, $op->fake_ppaddr,
			    $op->targ, $op->type, $op->flags,
			    $op->private, ${$op->first}, ${$op->other}));
    my $ix = $logopsect->index;
    $init->add(sprintf("logop_list[$ix].op_ppaddr = %s;", $op->ppaddr))
        unless $optimize_ppaddr;
    savesym($op, "(OP*)&logop_list[$ix]");
}

sub B::LOOP::save {
    my ($op, $level) = @_;
    my $sym = objsym($op);
    return $sym if defined $sym;
    #warn sprintf("LOOP: redoop %s, nextop %s, lastop %s\n",
    #		 peekop($op->redoop), peekop($op->nextop),
    #		 peekop($op->lastop)); # debug
    $loopsect->add(sprintf("s\\_%x, s\\_%x, %s, %u, %u, $op_os, 0x%x, 0x%x, s\\_%x, s\\_%x, s\\_%x, s\\_%x, s\\_%x",
			   ${$op->next}, ${$op->sibling}, $op->fake_ppaddr,
			   $op->targ, $op->type, $op->flags,
			   $op->private, ${$op->first}, ${$op->last},
			   ${$op->redoop}, ${$op->nextop},
			   ${$op->lastop}));
    my $ix = $loopsect->index;
    $init->add(sprintf("loop_list[$ix].op_ppaddr = %s;", $op->ppaddr))
        unless $optimize_ppaddr;
    savesym($op, "(OP*)&loop_list[$ix]");
}

sub B::PVOP::save {
    my ($op, $level) = @_;
    my $sym = objsym($op);
    return $sym if defined $sym;
    $pvopsect->add(sprintf("s\\_%x, s\\_%x, %s,  %u, %u, $op_os, 0x%x, 0x%x, %s",
			   ${$op->next}, ${$op->sibling}, $op->fake_ppaddr,
			   $op->targ, $op->type, $op->flags,
			   $op->private, cstring($op->pv)));
    my $ix = $pvopsect->index;
    $init->add(sprintf("pvop_list[$ix].op_ppaddr = %s;", $op->ppaddr))
        unless $optimize_ppaddr;
    savesym($op, "(OP*)&pvop_list[$ix]");
}

sub B::SVOP::save {
    my ($op, $level) = @_;
    my $sym = objsym($op);
    return $sym if defined $sym;
    my $sv = $op->sv;
    my $svsym = '(SV*)' . $sv->save;
    my $is_const_addr = $svsym =~ m/Null|\&/;
    $svopsect->add(sprintf("s\\_%x, s\\_%x, %s, %u, %u, $op_os, 0x%x, 0x%x, %s",
			   ${$op->next}, ${$op->sibling}, $op->fake_ppaddr,
			   $op->targ, $op->type, $op->flags,
			   $op->private,
                           ( $is_const_addr ? $svsym : 'Nullsv' )));
    my $ix = $svopsect->index;
    $init->add(sprintf("svop_list[$ix].op_ppaddr = %s;", $op->ppaddr))
        unless $optimize_ppaddr;
    $init->add("svop_list[$ix].op_sv = $svsym;")
        unless $is_const_addr;
    savesym($op, "(OP*)&svop_list[$ix]");
}

sub B::PADOP::save {
    my ($op, $level) = @_;
    my $sym = objsym($op);
    return $sym if defined $sym;
    $padopsect->add(sprintf("s\\_%x, s\\_%x, %s, %u, %u, $op_os, 0x%x, 0x%x, %d",
			   ${$op->next}, ${$op->sibling}, $op->fake_ppaddr,
			   $op->targ, $op->type, $op->flags,
			   $op->private,$op->padix));
    my $ix = $padopsect->index;
    $init->add(sprintf("padop_list[$ix].op_ppaddr = %s;", $op->ppaddr))
        unless $optimize_ppaddr;
#    $init->add(sprintf("padop_list[$ix].op_padix = %ld;", $op->padix));
    savesym($op, "(OP*)&padop_list[$ix]");
}

sub B::COP::save {
    my ($op, $level) = @_;
    my $sym = objsym($op);
    return $sym if defined $sym;
    warn sprintf("COP: line %d file %s\n", $op->line, $op->file)
	if $debug_cops;
    # shameless cut'n'paste from B::Deparse
    my $warn_sv;
    my $warnings = $op->warnings;
    my $is_special = $warnings->isa("B::SPECIAL");
    if ($is_special && $$warnings == 4) {
        # use warnings 'all';
        $warn_sv = $optimize_warn_sv ?
            'INT2PTR(SV*,1)' :
            'pWARN_ALL';
    }
    elsif ($is_special && $$warnings == 5) {
        # no warnings 'all';
        $warn_sv = $optimize_warn_sv ?
            'INT2PTR(SV*,2)' :
            'pWARN_NONE';
    }
    elsif ($is_special) {
        # use warnings;
        $warn_sv = $optimize_warn_sv ?
            'INT2PTR(SV*,3)' :
            'pWARN_STD';
    }
    else {
        # something else
        $warn_sv = $warnings->save;
    }

    $copsect->add(sprintf("s\\_%x, s\\_%x, %s, %u, %u, $op_os, 0x%x, 0x%x, %s, NULL, NULL, %u, %d, %u, %s",
			  ${$op->next}, ${$op->sibling}, $op->fake_ppaddr,
			  $op->targ, $op->type, $op->flags,
			  $op->private, cstring($op->label), $op->cop_seq,
			  $op->arybase, $op->line,
                          ( $optimize_warn_sv ? $warn_sv : 'NULL' )));
    my $ix = $copsect->index;
    $init->add(sprintf("cop_list[$ix].op_ppaddr = %s;", $op->ppaddr))
        unless $optimize_ppaddr;
    $init->add(sprintf("cop_list[$ix].cop_warnings = %s;", $warn_sv ))
        unless $optimize_warn_sv;
    $init->add(sprintf("CopFILE_set(&cop_list[$ix], %s);", cstring($op->file)),
	       sprintf("CopSTASHPV_set(&cop_list[$ix], %s);", cstring($op->stashpv)));

    savesym($op, "(OP*)&cop_list[$ix]");
}

sub B::PMOP::save {
    my ($op, $level) = @_;
    my $sym = objsym($op);
    return $sym if defined $sym;
    my $replroot = $op->pmreplroot;
    my $replstart = $op->pmreplstart;
    my $replrootfield;
    my $replstartfield = sprintf("s\\_%x", $$replstart);
    my $gvsym;
    my $ppaddr = $op->ppaddr;
    # under ithreads, OP_PUSHRE.op_replroot is an integer
    $replrootfield = sprintf("s\\_%x", $$replroot) if ref $replroot;
    if($ithreads && $op->name eq "pushre") {
        $replrootfield = "INT2PTR(OP*,${replroot})";
    } elsif ($$replroot) {
	# OP_PUSHRE (a mutated version of OP_MATCH for the regexp
	# argument to a split) stores a GV in op_pmreplroot instead
	# of a substitution syntax tree. We don't want to walk that...
	if ($op->name eq "pushre") {
	    $gvsym = $replroot->save;
#	    warn "PMOP::save saving a pp_pushre with GV $gvsym\n"; # debug
	    $replrootfield = 0;
	} else {
	    $replstartfield = saveoptree("*ignore*", $replroot, $replstart);
	}
    }
    # pmnext handling is broken in perl itself, I think. Bad op_pmnext
    # fields aren't noticed in perl's runtime (unless you try reset) but we
    # segfault when trying to dereference it to find op->op_pmnext->op_type
    $pmopsect->add(sprintf("s\\_%x, s\\_%x, %s, %u, %u, $op_os, 0x%x, 0x%x, s\\_%x, s\\_%x, %s, %s, 0, %u, 0x%x, 0x%x, 0x%x",
			   ${$op->next}, ${$op->sibling}, $op->fake_ppaddr, $op->targ,
			   $op->type, $op->flags, $op->private,
			   ${$op->first}, ${$op->last}, 
			   $replrootfield, $replstartfield,
                           ( $ithreads ? $op->pmoffset : 0 ),
			   $op->pmflags, $op->pmpermflags, $op->pmdynflags ));
    my $pm = sprintf("pmop_list[%d]", $pmopsect->index);
    $init->add(sprintf("$pm.op_ppaddr = %s;", $ppaddr))
        unless $optimize_ppaddr;
    my $re = $op->precomp;
    if (defined($re)) {
	my( $resym, $relen ) = savere( $re );
	$init->add(sprintf("PM_SETRE(&$pm,pregcomp($resym, $resym + %u, &$pm));",
			   $relen));
    }
    if ($gvsym) {
	$init->add("$pm.op_pmreplroot = (OP*)$gvsym;");
    }
    savesym($op, "(OP*)&$pm");
}

sub B::SPECIAL::save {
    my ($sv) = @_;
    # special case: $$sv is not the address but an index into specialsv_list
#   warn "SPECIAL::save specialsv $$sv\n"; # debug
    my $sym = $specialsv_name[$$sv];
    if (!defined($sym)) {
	confess "unknown specialsv index $$sv passed to B::SPECIAL::save";
    }
    return $sym;
}

sub B::OBJECT::save {}

sub B::NULL::save {
    my ($sv) = @_;
    my $sym = objsym($sv);
    return $sym if defined $sym;
#   warn "Saving SVt_NULL SV\n"; # debug
    # debug
    if ($$sv == 0) {
    	warn "NULL::save for sv = 0 called from @{[(caller(1))[3]]}\n";
	return savesym($sv, "(void*)Nullsv /* XXX */");
    }
    $svsect->add(sprintf("0, %u, 0x%x", $sv->REFCNT , $sv->FLAGS));
    return savesym($sv, sprintf("&sv_list[%d]", $svsect->index));
}

sub B::IV::save {
    my ($sv) = @_;
    my $sym = objsym($sv);
    return $sym if defined $sym;
    $xpvivsect->add(sprintf("0, 0, 0, %d", $sv->IVX));
    $svsect->add(sprintf("&xpviv_list[%d], %lu, 0x%x",
			 $xpvivsect->index, $sv->REFCNT , $sv->FLAGS));
    return savesym($sv, sprintf("&sv_list[%d]", $svsect->index));
}

sub B::NV::save {
    my ($sv) = @_;
    my $sym = objsym($sv);
    return $sym if defined $sym;
    my $val= $sv->NVX;
    $val .= '.00' if $val =~ /^-?\d+$/;
    $xpvnvsect->add(sprintf("0, 0, 0, %d, %s", $sv->IVX, $val));
    $svsect->add(sprintf("&xpvnv_list[%d], %lu, 0x%x",
			 $xpvnvsect->index, $sv->REFCNT , $sv->FLAGS));
    return savesym($sv, sprintf("&sv_list[%d]", $svsect->index));
}

sub savepvn {
    my ($dest,$pv) = @_;
    my @res;
    # work with byte offsets/lengths
    my $pv = pack "a*", $pv;
    if (defined $max_string_len && length($pv) > $max_string_len) {
	push @res, sprintf("New(0,%s,%u,char);", $dest, length($pv)+1);
	my $offset = 0;
	while (length $pv) {
	    my $str = substr $pv, 0, $max_string_len, '';
	    push @res, sprintf("Copy(%s,$dest+$offset,%u,char);",
			       cstring($str), length($str));
	    $offset += length $str;
	}
	push @res, sprintf("%s[%u] = '\\0';", $dest, $offset);
    }
    else {
	push @res, sprintf("%s = savepvn(%s, %u);", $dest,
			   cstring($pv), length($pv));
    }
    return @res;
}

sub B::PVLV::save {
    my ($sv) = @_;
    my $sym = objsym($sv);
    return $sym if defined $sym;
    my $pv = $sv->PV;
    my $len = length($pv);
    my ($pvsym, $pvmax) = savepv($pv);
    my ($lvtarg, $lvtarg_sym);
    $xpvlvsect->add(sprintf("%s, %u, %u, %d, %g, 0, 0, %u, %u, 0, %s",
			    $pvsym, $len, $pvmax, $sv->IVX, $sv->NVX, 
			    $sv->TARGOFF, $sv->TARGLEN, cchar($sv->TYPE)));
    $svsect->add(sprintf("&xpvlv_list[%d], %lu, 0x%x",
			 $xpvlvsect->index, $sv->REFCNT , $sv->FLAGS));
    if (!$pv_copy_on_grow) {
	$init->add(savepvn(sprintf("xpvlv_list[%d].xpv_pv",
				   $xpvlvsect->index), $pv));
    }
    $sv->save_magic;
    return savesym($sv, sprintf("&sv_list[%d]", $svsect->index));
}

sub B::PVIV::save {
    my ($sv) = @_;
    my $sym = objsym($sv);
    return $sym if defined $sym;
    my( $savesym, $pvmax, $len, $pv ) = save_pv_or_rv( $sv );
    $xpvivsect->add(sprintf("%s, %u, %u, %d", $savesym, $len, $pvmax, $sv->IVX));
    $svsect->add(sprintf("&xpviv_list[%d], %u, 0x%x",
			 $xpvivsect->index, $sv->REFCNT , $sv->FLAGS));
    if (defined($pv) && !$pv_copy_on_grow) {
	$init->add(savepvn(sprintf("xpviv_list[%d].xpv_pv",
				   $xpvivsect->index), $pv));
    }
    return savesym($sv, sprintf("&sv_list[%d]", $svsect->index));
}

sub B::PVNV::save {
    my ($sv) = @_;
    my $sym = objsym($sv);
    return $sym if defined $sym;
    my( $savesym, $pvmax, $len, $pv ) = save_pv_or_rv( $sv );
    my $val= $sv->NVX;
    $val .= '.00' if $val =~ /^-?\d+$/;
    $xpvnvsect->add(sprintf("%s, %u, %u, %d, %s",
			    $savesym, $len, $pvmax, $sv->IVX, $val));
    $svsect->add(sprintf("&xpvnv_list[%d], %lu, 0x%x",
			 $xpvnvsect->index, $sv->REFCNT , $sv->FLAGS));
    if (defined($pv) && !$pv_copy_on_grow) {
	$init->add(savepvn(sprintf("xpvnv_list[%d].xpv_pv",
				   $xpvnvsect->index), $pv));
    }
    return savesym($sv, sprintf("&sv_list[%d]", $svsect->index));
}

sub B::BM::save {
    my ($sv) = @_;
    my $sym = objsym($sv);
    return $sym if defined $sym;
    my $pv = pack "a*", ($sv->PV . "\0" . $sv->TABLE);
    my $len = length($pv);
    $xpvbmsect->add(sprintf("0, %u, %u, %d, %s, 0, 0, %d, %u, 0x%x",
			    $len, $len + 258, $sv->IVX, $sv->NVX,
			    $sv->USEFUL, $sv->PREVIOUS, $sv->RARE));
    $svsect->add(sprintf("&xpvbm_list[%d], %lu, 0x%x",
			 $xpvbmsect->index, $sv->REFCNT , $sv->FLAGS));
    $sv->save_magic;
    $init->add(savepvn(sprintf("xpvbm_list[%d].xpv_pv",
			       $xpvbmsect->index), $pv),
	       sprintf("xpvbm_list[%d].xpv_cur = %u;",
		       $xpvbmsect->index, $len - 257));
    return savesym($sv, sprintf("&sv_list[%d]", $svsect->index));
}

sub B::PV::save {
    my ($sv) = @_;
    my $sym = objsym($sv);
    return $sym if defined $sym;
    my( $savesym, $pvmax, $len, $pv ) = save_pv_or_rv( $sv );
    $xpvsect->add(sprintf("%s, %u, %u", $savesym, $len, $pvmax));
    $svsect->add(sprintf("&xpv_list[%d], %lu, 0x%x",
			 $xpvsect->index, $sv->REFCNT , $sv->FLAGS));
    if (defined($pv) && !$pv_copy_on_grow) {
	$init->add(savepvn(sprintf("xpv_list[%d].xpv_pv",
				   $xpvsect->index), $pv));
    }
    return savesym($sv, sprintf("&sv_list[%d]", $svsect->index));
}

sub B::PVMG::save {
    my ($sv) = @_;
    my $sym = objsym($sv);
    return $sym if defined $sym;
    my( $savesym, $pvmax, $len, $pv ) = save_pv_or_rv( $sv );

    $xpvmgsect->add(sprintf("%s, %u, %u, %d, %s, 0, 0",
                            $savesym, $len, $pvmax,
                            $sv->IVX, $sv->NVX));
    $svsect->add(sprintf("&xpvmg_list[%d], %lu, 0x%x",
                         $xpvmgsect->index, $sv->REFCNT , $sv->FLAGS));
    if (defined($pv) && !$pv_copy_on_grow) {
        $init->add(savepvn(sprintf("xpvmg_list[%d].xpv_pv",
                                   $xpvmgsect->index), $pv));
    }
    $sym = savesym($sv, sprintf("&sv_list[%d]", $svsect->index));
    $sv->save_magic;
    return $sym;
}

sub B::PVMG::save_magic {
    my ($sv) = @_;
    #warn sprintf("saving magic for %s (0x%x)\n", class($sv), $$sv); # debug
    my $stash = $sv->SvSTASH;
    $stash->save;
    if ($$stash) {
	warn sprintf("xmg_stash = %s (0x%x)\n", $stash->NAME, $$stash)
	    if $debug_mg;
	# XXX Hope stash is already going to be saved.
	$init->add(sprintf("SvSTASH(s\\_%x) = s\\_%x;", $$sv, $$stash));
    }
    my @mgchain = $sv->MAGIC;
    my ($mg, $type, $obj, $ptr,$len,$ptrsv);
    foreach $mg (@mgchain) {
	$type = $mg->TYPE;
	$ptr = $mg->PTR;
	$len=$mg->LENGTH;
	if ($debug_mg) {
	    warn sprintf("magic %s (0x%x), obj %s (0x%x), type %s, ptr %s\n",
			 class($sv), $$sv, class($obj), $$obj,
			 cchar($type), cstring($ptr));
	}

        unless( $type eq 'r' ) {
          $obj = $mg->OBJ;
          $obj->save;
        }

	if ($len == HEf_SVKEY){
		#The pointer is an SV*
		$ptrsv=svref_2object($ptr)->save;
		$init->add(sprintf("sv_magic((SV*)s\\_%x, (SV*)s\\_%x, %s,(char *) %s, %d);",
			   $$sv, $$obj, cchar($type),$ptrsv,$len));
        }elsif( $type eq 'r' ){
            my $rx = $mg->REGEX;
            my $pmop = $REGEXP{$rx};

            confess "PMOP not found for REGEXP $rx" unless $pmop;

            my( $resym, $relen ) = savere( $mg->precomp );
            my $pmsym = $pmop->save;
            $init->add( split /\n/, sprintf <<CODE, $$sv, cchar($type), cstring($ptr) );
{
    REGEXP* rx = pregcomp($resym, $resym + $relen, (PMOP*)$pmsym);
    sv_magic((SV*)s\\_%x, (SV*)rx, %s, %s, %d);
}
CODE
        }else{
		$init->add(sprintf("sv_magic((SV*)s\\_%x, (SV*)s\\_%x, %s, %s, %d);",
			   $$sv, $$obj, cchar($type),cstring($ptr),$len));
	}
    }
}

sub B::RV::save {
    my ($sv) = @_;
    my $sym = objsym($sv);
    return $sym if defined $sym;
    my $rv = save_rv( $sv );
    # GVs need to be handled at runtime
    if( ref( $sv->RV ) eq 'B::GV' ) {
        $xrvsect->add( "(SV*)Nullgv" );
        $init->add(sprintf("xrv_list[%d].xrv_rv = (SV*)%s;\n", $xrvsect->index, $rv));
    }
    # and stashes, too
    elsif( $sv->RV->isa( 'B::HV' ) && $sv->RV->NAME ) {
        $xrvsect->add( "(SV*)Nullhv" );
        $init->add(sprintf("xrv_list[%d].xrv_rv = (SV*)%s;\n", $xrvsect->index, $rv));
    }
    else {
        $xrvsect->add($rv);
    }
    $svsect->add(sprintf("&xrv_list[%d], %lu, 0x%x",
			 $xrvsect->index, $sv->REFCNT , $sv->FLAGS));
    return savesym($sv, sprintf("&sv_list[%d]", $svsect->index));
}

sub try_autoload {
    my ($cvstashname, $cvname) = @_;
    warn sprintf("No definition for sub %s::%s\n", $cvstashname, $cvname);
    # Handle AutoLoader classes explicitly. Any more general AUTOLOAD
    # use should be handled by the class itself.
    no strict 'refs';
    my $isa = \@{"$cvstashname\::ISA"};
    if (grep($_ eq "AutoLoader", @$isa)) {
	warn "Forcing immediate load of sub derived from AutoLoader\n";
	# Tweaked version of AutoLoader::AUTOLOAD
	my $dir = $cvstashname;
	$dir =~ s(::)(/)g;
	eval { require "auto/$dir/$cvname.al" };
	if ($@) {
	    warn qq(failed require "auto/$dir/$cvname.al": $@\n);
	    return 0;
	} else {
	    return 1;
	}
    }
}
sub Dummy_initxs{};
sub B::CV::save {
    my ($cv) = @_;
    my $sym = objsym($cv);
    if (defined($sym)) {
#	warn sprintf("CV 0x%x already saved as $sym\n", $$cv); # debug
	return $sym;
    }
    # Reserve a place in svsect and xpvcvsect and record indices
    my $gv = $cv->GV;
    my ($cvname, $cvstashname);
    if ($$gv){
    	$cvname = $gv->NAME;
    	$cvstashname = $gv->STASH->NAME;
    }
    my $root = $cv->ROOT;
    my $cvxsub = $cv->XSUB;
    my $isconst = $cv->CvFLAGS & CVf_CONST;
    if( $isconst ) {
        my $value = $cv->XSUBANY;
        my $stash = $gv->STASH;
        my $vsym = $value->save;
        my $stsym = $stash->save;
        my $name = cstring($cvname);
        $decl->add( "static CV* cv$cv_index;" );
        $init->add( "cv$cv_index = newCONSTSUB( $stsym, NULL, $vsym );" );
        my $sym = savesym( $cv, "cv$cv_index" );
        $cv_index++;
        return $sym;
    }
    #INIT is removed from the symbol table, so this call must come
    # from PL_initav->save. Re-bootstrapping  will push INIT back in
    # so nullop should be sent.
    if (!$isconst && $cvxsub && ($cvname ne "INIT")) {
	my $egv = $gv->EGV;
	my $stashname = $egv->STASH->NAME;
         if ($cvname eq "bootstrap")
          { 
           my $file = $gv->FILE;
           $decl->add("/* bootstrap $file */"); 
           warn "Bootstrap $stashname $file\n";
           # if it not isa('DynaLoader'), it should hopefully be XSLoaded
           # ( attributes being an exception, of course )
           if( $stashname ne 'attributes' &&
               !UNIVERSAL::isa($stashname,'DynaLoader') ) {
            $xsub{$stashname}='Dynamic-XSLoaded';
            $use_xsloader = 1;
           }
           else {
            $xsub{$stashname}='Dynamic';
           }
	   # $xsub{$stashname}='Static' unless  $xsub{$stashname};
           return qq/NULL/;
          }
         else
          {
           # XSUBs for IO::File, IO::Handle, IO::Socket,
           # IO::Seekable and IO::Poll
           # are defined in IO.xs, so let's bootstrap it
           svref_2object( \&IO::bootstrap )->save
            if grep { $stashname eq $_ } qw(IO::File IO::Handle IO::Socket
                                              IO::Seekable IO::Poll);
          }
        warn sprintf("stub for XSUB $cvstashname\:\:$cvname CV 0x%x\n", $$cv) if $debug_cv;
	return qq/(perl_get_cv("$stashname\:\:$cvname",TRUE))/;
    }
    if ($cvxsub && $cvname eq "INIT") {
	 no strict 'refs';
   	 return svref_2object(\&Dummy_initxs)->save;
    }
    my $sv_ix = $svsect->index + 1;
    $svsect->add("svix$sv_ix");
    my $xpvcv_ix = $xpvcvsect->index + 1;
    $xpvcvsect->add("xpvcvix$xpvcv_ix");
    # Save symbol now so that GvCV() doesn't recurse back to us via CvGV()
    $sym = savesym($cv, "&sv_list[$sv_ix]");
    warn sprintf("saving $cvstashname\:\:$cvname CV 0x%x as $sym\n", $$cv) if $debug_cv;
    if (!$$root && !$cvxsub) {
	if (try_autoload($cvstashname, $cvname)) {
	    # Recalculate root and xsub
	    $root = $cv->ROOT;
	    $cvxsub = $cv->XSUB;
	    if ($$root || $cvxsub) {
		warn "Successful forced autoload\n";
	    }
	}
    }
    my $startfield = 0;
    my $padlist = $cv->PADLIST;
    my $pv = $cv->PV;
    my $xsub = 0;
    my $xsubany = "Nullany";
    if ($$root) {
	warn sprintf("saving op tree for CV 0x%x, root = 0x%x\n",
		     $$cv, $$root) if $debug_cv;
	my $ppname = "";
	if ($$gv) {
	    my $stashname = $gv->STASH->NAME;
	    my $gvname = $gv->NAME;
	    if ($gvname ne "__ANON__") {
		$ppname = (${$gv->FORM} == $$cv) ? "pp_form_" : "pp_sub_";
		$ppname .= ($stashname eq "main") ?
			    $gvname : "$stashname\::$gvname";
		$ppname =~ s/::/__/g;
	        if ($gvname eq "INIT"){
		       $ppname .= "_$initsub_index";
		       $initsub_index++;
		    }
	    }
	}
	if (!$ppname) {
	    $ppname = "pp_anonsub_$anonsub_index";
	    $anonsub_index++;
	}
	$startfield = saveoptree($ppname, $root, $cv->START, $padlist->ARRAY);
	warn sprintf("done saving op tree for CV 0x%x, name %s, root 0x%x\n",
		     $$cv, $ppname, $$root) if $debug_cv;
	if ($$padlist) {
	    warn sprintf("saving PADLIST 0x%x for CV 0x%x\n",
			 $$padlist, $$cv) if $debug_cv;
	    $padlist->save;
	    warn sprintf("done saving PADLIST 0x%x for CV 0x%x\n",
			 $$padlist, $$cv) if $debug_cv;
	}
    }
    else {
	warn sprintf("No definition for sub %s::%s (unable to autoload)\n",
		     $cvstashname, $cvname); # debug
    }              
    $pv = '' unless defined $pv; # Avoid use of undef warnings
    $symsect->add(sprintf("xpvcvix%d\t%s, %u, 0, %d, %s, 0, Nullhv, Nullhv, %s, s\\_%x, $xsub, $xsubany, Nullgv, \"\", %d, s\\_%x, (CV*)s\\_%x, 0x%x, 0x%x",
			  $xpvcv_ix, cstring($pv), length($pv), $cv->IVX,
			  $cv->NVX, $startfield, ${$cv->ROOT}, $cv->DEPTH,
                        $$padlist, ${$cv->OUTSIDE}, $cv->CvFLAGS,
			$cv->OUTSIDE_SEQ));

    if (${$cv->OUTSIDE} == ${main_cv()}){
	$init->add(sprintf("CvOUTSIDE(s\\_%x)=PL_main_cv;",$$cv));
	$init->add(sprintf("SvREFCNT_inc(PL_main_cv);"));
    }

    if ($$gv) {
	$gv->save;
	$init->add(sprintf("CvGV(s\\_%x) = s\\_%x;",$$cv,$$gv));
	warn sprintf("done saving GV 0x%x for CV 0x%x\n",
		     $$gv, $$cv) if $debug_cv;
    }
    if( $ithreads ) {
        $init->add( savepvn( "CvFILE($sym)", $cv->FILE) );
    }
    else {
        $init->add(sprintf("CvFILE($sym) = %s;", cstring($cv->FILE)));
    }
    my $stash = $cv->STASH;
    if ($$stash) {
	$stash->save;
	$init->add(sprintf("CvSTASH(s\\_%x) = s\\_%x;", $$cv, $$stash));
	warn sprintf("done saving STASH 0x%x for CV 0x%x\n",
		     $$stash, $$cv) if $debug_cv;
    }
    $symsect->add(sprintf("svix%d\t(XPVCV*)&xpvcv_list[%u], %lu, 0x%x",
			  $sv_ix, $xpvcv_ix, $cv->REFCNT +1*0 , $cv->FLAGS));
    return $sym;
}

sub B::GV::save {
    my ($gv) = @_;
    my $sym = objsym($gv);
    if (defined($sym)) {
	#warn sprintf("GV 0x%x already saved as $sym\n", $$gv); # debug
	return $sym;
    } else {
	my $ix = $gv_index++;
	$sym = savesym($gv, "gv_list[$ix]");
	#warn sprintf("Saving GV 0x%x as $sym\n", $$gv); # debug
    }
    my $is_empty = $gv->is_empty;
    my $gvname = $gv->NAME;
    my $fullname = $gv->STASH->NAME . "::" . $gvname;
    my $name = cstring($fullname);
    #warn "GV name is $name\n"; # debug
    my $egvsym;
    unless ($is_empty) {
	my $egv = $gv->EGV;
	if ($$gv != $$egv) {
	    #warn(sprintf("EGV name is %s, saving it now\n",
	    #	     $egv->STASH->NAME . "::" . $egv->NAME)); # debug
	    $egvsym = $egv->save;
	}
    }
    $init->add(qq[$sym = gv_fetchpv($name, TRUE, SVt_PV);],
	       sprintf("SvFLAGS($sym) = 0x%x;", $gv->FLAGS ),
	       sprintf("GvFLAGS($sym) = 0x%x;", $gv->GvFLAGS));
    $init->add(sprintf("GvLINE($sym) = %u;", $gv->LINE)) unless $is_empty;
    # XXX hack for when Perl accesses PVX of GVs
    $init->add("SvPVX($sym) = emptystring;\n");
    # Shouldn't need to do save_magic since gv_fetchpv handles that
    #$gv->save_magic;
    # XXX will always be > 1!!!
    my $refcnt = $gv->REFCNT + 1;
    $init->add(sprintf("SvREFCNT($sym) += %u;", $refcnt - 1 )) if $refcnt > 1;

    return $sym if $is_empty;

    # XXX B::walksymtable creates an extra reference to the GV
    my $gvrefcnt = $gv->GvREFCNT;
    if ($gvrefcnt > 1) {
	$init->add(sprintf("GvREFCNT($sym) += %u;", $gvrefcnt - 1));
    }
    # some non-alphavetic globs require some parts to be saved
    # ( ex. %!, but not $! )
    sub Save_HV() { 1 }
    sub Save_AV() { 2 }
    sub Save_SV() { 4 }
    sub Save_CV() { 8 }
    sub Save_FORM() { 16 }
    sub Save_IO() { 32 }
    my $savefields = 0;
    if( $gvname !~ /^([^A-Za-z]|STDIN|STDOUT|STDERR|ARGV|SIG|ENV)$/ ) {
        $savefields = Save_HV|Save_AV|Save_SV|Save_CV|Save_FORM|Save_IO;
    }
    elsif( $gvname eq '!' ) {
        $savefields = Save_HV;
    }
    # attributes::bootstrap is created in perl_parse
    # saving it would overwrite it, because perl_init() is
    # called after perl_parse()
    $savefields&=~Save_CV if $fullname eq 'attributes::bootstrap';

    # save it
    # XXX is that correct?
    if (defined($egvsym) && $egvsym !~ m/Null/ ) {
	# Shared glob *foo = *bar
	$init->add("gp_free($sym);",
		   "GvGP($sym) = GvGP($egvsym);");
    } elsif ($savefields) {
	# Don't save subfields of special GVs (*_, *1, *# and so on)
#	warn "GV::save saving subfields\n"; # debug
	my $gvsv = $gv->SV;
	if ($$gvsv && $savefields&Save_SV) {
	    $gvsv->save;
	    $init->add(sprintf("GvSV($sym) = s\\_%x;", $$gvsv));
#	    warn "GV::save \$$name\n"; # debug
	}
	my $gvav = $gv->AV;
	if ($$gvav && $savefields&Save_AV) {
	    $gvav->save;
	    $init->add(sprintf("GvAV($sym) = s\\_%x;", $$gvav));
#	    warn "GV::save \@$name\n"; # debug
	}
	my $gvhv = $gv->HV;
	if ($$gvhv && $savefields&Save_HV) {
	    $gvhv->save;
	    $init->add(sprintf("GvHV($sym) = s\\_%x;", $$gvhv));
#	    warn "GV::save \%$name\n"; # debug
	}
	my $gvcv = $gv->CV;
	if ($$gvcv && $savefields&Save_CV) {
	    my $origname=cstring($gvcv->GV->EGV->STASH->NAME .
		 "::" . $gvcv->GV->EGV->NAME);  
	    if (0 && $gvcv->XSUB && $name ne $origname) { #XSUB alias
	        # must save as a 'stub' so newXS() has a CV to populate
                $init->add("{ CV *cv;");
                $init->add("\tcv=perl_get_cv($origname,TRUE);");
                $init->add("\tGvCV($sym)=cv;");
                $init->add("\tSvREFCNT_inc((SV *)cv);");
                $init->add("}");    
	    } else {
               $init->add(sprintf("GvCV($sym) = (CV*)(%s);", $gvcv->save));
#              warn "GV::save &$name\n"; # debug
	    } 
        }     
	$init->add(sprintf("GvFILE($sym) = %s;", cstring($gv->FILE)));
#	warn "GV::save GvFILE(*$name)\n"; # debug
	my $gvform = $gv->FORM;
	if ($$gvform && $savefields&Save_FORM) {
	    $gvform->save;
	    $init->add(sprintf("GvFORM($sym) = (CV*)s\\_%x;", $$gvform));
#	    warn "GV::save GvFORM(*$name)\n"; # debug
	}
	my $gvio = $gv->IO;
	if ($$gvio && $savefields&Save_IO) {
	    $gvio->save;
	    $init->add(sprintf("GvIOp($sym) = s\\_%x;", $$gvio));
            if( $fullname =~ m/::DATA$/ && $save_data_fh ) {
                no strict 'refs';
                my $fh = *{$fullname}{IO};
                use strict 'refs';
                $gvio->save_data( $fullname, <$fh> ) if $fh->opened;
            }
#	    warn "GV::save GvIO(*$name)\n"; # debug
	}
    }
    return $sym;
}

sub B::AV::save {
    my ($av) = @_;
    my $sym = objsym($av);
    return $sym if defined $sym;
    my $avflags = $av->AvFLAGS;
    $xpvavsect->add(sprintf("0, -1, -1, 0, 0.0, 0, Nullhv, 0, 0, 0x%x",
			    $avflags));
    $svsect->add(sprintf("&xpvav_list[%d], %lu, 0x%x",
			 $xpvavsect->index, $av->REFCNT  , $av->FLAGS));
    my $sv_list_index = $svsect->index;
    my $fill = $av->FILL;
    $av->save_magic;
    warn sprintf("saving AV 0x%x FILL=$fill AvFLAGS=0x%x", $$av, $avflags)
	if $debug_av;
    # XXX AVf_REAL is wrong test: need to save comppadlist but not stack
    #if ($fill > -1 && ($avflags & AVf_REAL)) {
    if ($fill > -1) {
	my @array = $av->ARRAY;
	if ($debug_av) {
	    my $el;
	    my $i = 0;
	    foreach $el (@array) {
		warn sprintf("AV 0x%x[%d] = %s 0x%x\n",
			     $$av, $i++, class($el), $$el);
	    }
	}
#	my @names = map($_->save, @array);
	# XXX Better ways to write loop?
	# Perhaps svp[0] = ...; svp[1] = ...; svp[2] = ...;
	# Perhaps I32 i = 0; svp[i++] = ...; svp[i++] = ...; svp[i++] = ...;

        # micro optimization: op/pat.t ( and other code probably )
        # has very large pads ( 20k/30k elements ) passing them to
        # ->add is a performance bottleneck: passing them as a
        # single string cuts runtime from 6min20sec to 40sec

        # you want to keep this out of the no_split/split
        # map("\t*svp++ = (SV*)$_;", @names),
        my $acc = '';
        foreach my $i ( 0..$#array ) {
              $acc .= "\t*svp++ = (SV*)" . $array[$i]->save . ";\n\t";
        }
        $acc .= "\n";

        $init->no_split;
	$init->add("{",
		   "\tSV **svp;",
		   "\tAV *av = (AV*)&sv_list[$sv_list_index];",
		   "\tav_extend(av, $fill);",
		   "\tsvp = AvARRAY(av);" );
        $init->add($acc);
	$init->add("\tAvFILLp(av) = $fill;",
		   "}");
        $init->split;
        # we really added a lot of lines ( B::C::InitSection->add
        # should really scan for \n, but that would slow
        # it down
        $init->inc_count( $#array );
    } else {
	my $max = $av->MAX;
	$init->add("av_extend((AV*)&sv_list[$sv_list_index], $max);")
	    if $max > -1;
    }
    return savesym($av, "(AV*)&sv_list[$sv_list_index]");
}

sub B::HV::save {
    my ($hv) = @_;
    my $sym = objsym($hv);
    return $sym if defined $sym;
    my $name = $hv->NAME;
    if ($name) {
	# It's a stash

	# A perl bug means HvPMROOT isn't altered when a PMOP is freed. Usually
	# the only symptom is that sv_reset tries to reset the PMf_USED flag of
	# a trashed op but we look at the trashed op_type and segfault.
	#my $adpmroot = ${$hv->PMROOT};
	my $adpmroot = 0;
	$decl->add("static HV *hv$hv_index;");
	# XXX Beware of weird package names containing double-quotes, \n, ...?
	$init->add(qq[hv$hv_index = gv_stashpv("$name", TRUE);]);
	if ($adpmroot) {
	    $init->add(sprintf("HvPMROOT(hv$hv_index) = (PMOP*)s\\_%x;",
			       $adpmroot));
	}
	$sym = savesym($hv, "hv$hv_index");
	$hv_index++;
	return $sym;
    }
    # It's just an ordinary HV
    $xpvhvsect->add(sprintf("0, 0, %d, 0, 0.0, 0, Nullhv, %d, 0, 0, 0",
			    $hv->MAX, $hv->RITER));
    $svsect->add(sprintf("&xpvhv_list[%d], %lu, 0x%x",
			 $xpvhvsect->index, $hv->REFCNT  , $hv->FLAGS));
    my $sv_list_index = $svsect->index;
    my @contents = $hv->ARRAY;
    if (@contents) {
	my $i;
	for ($i = 1; $i < @contents; $i += 2) {
	    $contents[$i] = $contents[$i]->save;
	}
        $init->no_split;
	$init->add("{", "\tHV *hv = (HV*)&sv_list[$sv_list_index];");
	while (@contents) {
	    my ($key, $value) = splice(@contents, 0, 2);
	    $init->add(sprintf("\thv_store(hv, %s, %u, %s, %s);",
			       cstring($key),length(pack "a*",$key),
                               $value, hash($key)));
#	    $init->add(sprintf("\thv_store(hv, %s, %u, %s, %s);",
#			       cstring($key),length($key),$value, 0));
	}
	$init->add("}");
        $init->split;
    }
    $hv->save_magic();
    return savesym($hv, "(HV*)&sv_list[$sv_list_index]");
}

sub B::IO::save_data {
    my( $io, $globname, @data ) = @_;
    my $data = join '', @data;

    # XXX using $DATA might clobber it!
    my $sym = svref_2object( \\$data )->save;
    $init->add( split /\n/, <<CODE );
    {
        GV* gv = (GV*)gv_fetchpv( "$globname", TRUE, SVt_PV );
        SV* sv = $sym;
        GvSV( gv ) = sv;
    }
CODE
    # for PerlIO::scalar
    $use_xsloader = 1;
    $init->add_eval( sprintf 'open(%s, "<", $%s)', $globname, $globname );
}

sub B::IO::save {
    my ($io) = @_;
    my $sym = objsym($io);
    return $sym if defined $sym;
    my $pv = $io->PV;
    $pv = '' unless defined $pv;
    my $len = length($pv);
    $xpviosect->add(sprintf("0, %u, %u, %d, %s, 0, 0, 0, 0, 0, %d, %d, %d, %d, %s, Nullgv, %s, Nullgv, %s, Nullgv, %d, %s, 0x%x",
			    $len, $len+1, $io->IVX, $io->NVX, $io->LINES,
			    $io->PAGE, $io->PAGE_LEN, $io->LINES_LEFT,
			    cstring($io->TOP_NAME), cstring($io->FMT_NAME), 
			    cstring($io->BOTTOM_NAME), $io->SUBPROCESS,
			    cchar($io->IoTYPE), $io->IoFLAGS));
    $svsect->add(sprintf("&xpvio_list[%d], %lu, 0x%x",
			 $xpviosect->index, $io->REFCNT , $io->FLAGS));
    $sym = savesym($io, sprintf("(IO*)&sv_list[%d]", $svsect->index));
    # deal with $x = *STDIN/STDOUT/STDERR{IO}
    my $perlio_func;
    foreach ( qw(stdin stdout stderr) ) {
        $io->IsSTD($_) and $perlio_func = $_;
    }
    if( $perlio_func ) {
        $init->add( "IoIFP(${sym})=PerlIO_${perlio_func}();" );
        $init->add( "IoOFP(${sym})=PerlIO_${perlio_func}();" );
    }

    my ($field, $fsym);
    foreach $field (qw(TOP_GV FMT_GV BOTTOM_GV)) {
      	$fsym = $io->$field();
	if ($$fsym) {
	    $init->add(sprintf("Io$field($sym) = (GV*)s\\_%x;", $$fsym));
	    $fsym->save;
	}
    }
    $io->save_magic;
    return $sym;
}

sub B::SV::save {
    my $sv = shift;
    # This is where we catch an honest-to-goodness Nullsv (which gets
    # blessed into B::SV explicitly) and any stray erroneous SVs.
    return 0 unless $$sv;
    confess sprintf("cannot save that type of SV: %s (0x%x)\n",
		    class($sv), $$sv);
}

sub output_all {
    my $init_name = shift;
    my $section;
    my @sections = ($opsect, $unopsect, $binopsect, $logopsect, $condopsect,
		    $listopsect, $pmopsect, $svopsect, $padopsect, $pvopsect,
		    $loopsect, $copsect, $svsect, $xpvsect,
		    $xpvavsect, $xpvhvsect, $xpvcvsect, $xpvivsect, $xpvnvsect,
		    $xpvmgsect, $xpvlvsect, $xrvsect, $xpvbmsect, $xpviosect);
    $symsect->output(\*STDOUT, "#define %s\n");
    print "\n";
    output_declarations();
    foreach $section (@sections) {
	my $lines = $section->index + 1;
	if ($lines) {
	    my $name = $section->name;
	    my $typename = ($name eq "xpvcv") ? "XPVCV_or_similar" : uc($name);
	    print "Static $typename ${name}_list[$lines];\n";
	}
    }
    # XXX hack for when Perl accesses PVX of GVs
    print 'Static char emptystring[] = "\0";';

    $decl->output(\*STDOUT, "%s\n");
    print "\n";
    foreach $section (@sections) {
	my $lines = $section->index + 1;
	if ($lines) {
	    my $name = $section->name;
	    my $typename = ($name eq "xpvcv") ? "XPVCV_or_similar" : uc($name);
	    printf "static %s %s_list[%u] = {\n", $typename, $name, $lines;
	    $section->output(\*STDOUT, "\t{ %s }, /* %d */\n");
	    print "};\n\n";
	}
    }

    $init->output(\*STDOUT, "\t%s\n", $init_name );
    if ($verbose) {
	warn compile_stats();
	warn "NULLOP count: $nullop_count\n";
    }
}

sub output_declarations {
    print <<'EOT';
#ifdef BROKEN_STATIC_REDECL
#define Static extern
#else
#define Static static
#endif /* BROKEN_STATIC_REDECL */

#ifdef BROKEN_UNION_INIT
/*
 * Cribbed from cv.h with ANY (a union) replaced by void*.
 * Some pre-Standard compilers can't cope with initialising unions. Ho hum.
 */
typedef struct {
    char *	xpv_pv;		/* pointer to malloced string */
    STRLEN	xpv_cur;	/* length of xp_pv as a C string */
    STRLEN	xpv_len;	/* allocated size */
    IV		xof_off;	/* integer value */
    NV		xnv_nv;		/* numeric value, if any */
    MAGIC*	xmg_magic;	/* magic for scalar array */
    HV*		xmg_stash;	/* class package */

    HV *	xcv_stash;
    OP *	xcv_start;
    OP *	xcv_root;
    void      (*xcv_xsub) (pTHX_ CV*);
    ANY		xcv_xsubany;
    GV *	xcv_gv;
    char *	xcv_file;
    long	xcv_depth;	/* >= 2 indicates recursive call */
    AV *	xcv_padlist;
    CV *	xcv_outside;
    cv_flags_t	xcv_flags;
    U32		xcv_outside_seq; /* the COP sequence (at the point of our
				  * compilation) in the lexically enclosing
				  * sub */
} XPVCV_or_similar;
#define ANYINIT(i) i
#else
#define XPVCV_or_similar XPVCV
#define ANYINIT(i) {i}
#endif /* BROKEN_UNION_INIT */
#define Nullany ANYINIT(0)

#define UNUSED 0
#define sym_0 0
EOT
    print "static GV *gv_list[$gv_index];\n" if $gv_index;
    print "\n";
}


sub output_boilerplate {
    print <<'EOT';
#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"

/* Workaround for mapstart: the only op which needs a different ppaddr */
#undef Perl_pp_mapstart
#define Perl_pp_mapstart Perl_pp_grepstart
#undef OP_MAPSTART
#define OP_MAPSTART OP_GREPSTART
#define XS_DynaLoader_boot_DynaLoader boot_DynaLoader
EXTERN_C void boot_DynaLoader (pTHX_ CV* cv);

static void xs_init (pTHX);
static void dl_init (pTHX);
static PerlInterpreter *my_perl;
EOT
}

sub init_op_addr {
    my( $op_type, $num ) = @_;
    my $op_list = $op_type."_list";

    $init->add( split /\n/, <<EOT );
    {
        int i;

        for( i = 0; i < ${num}; ++i )
        {
            ${op_list}\[i].op_ppaddr = PL_ppaddr[INT2PTR(int,${op_list}\[i].op_ppaddr)];
        }
    }
EOT
}

sub init_op_warn {
    my( $op_type, $num ) = @_;
    my $op_list = $op_type."_list";

    # for resons beyond imagination, MSVC5 considers pWARN_ALL non-const
    $init->add( split /\n/, <<EOT );
    {
        int i;

        for( i = 0; i < ${num}; ++i )
        {
            switch( (int)(${op_list}\[i].cop_warnings) )
            {
            case 1:
                ${op_list}\[i].cop_warnings = pWARN_ALL;
                break;
            case 2:
                ${op_list}\[i].cop_warnings = pWARN_NONE;
                break;
            case 3:
                ${op_list}\[i].cop_warnings = pWARN_STD;
                break;
            default:
                break;
            }
        }
    }
EOT
}

sub output_main {
    print <<'EOT';
/* if USE_IMPLICIT_SYS, we need a 'real' exit */
#if defined(exit)
#undef exit
#endif

int
main(int argc, char **argv, char **env)
{
    int exitstatus;
    int i;
    char **fakeargv;
    GV* tmpgv;
    SV* tmpsv;
    int options_count;

    PERL_SYS_INIT3(&argc,&argv,&env);

    if (!PL_do_undump) {
	my_perl = perl_alloc();
	if (!my_perl)
	    exit(1);
	perl_construct( my_perl );
	PL_perl_destruct_level = 0;
    }
EOT
    if( $ithreads ) {
        # XXX init free elems!
        my $pad_len = regex_padav->FILL + 1 - 1; # first is an avref

        print <<EOT;
#ifdef USE_ITHREADS
    for( i = 0; i < $pad_len; ++i ) {
        av_push( PL_regex_padav, newSViv(0) );
    }
    PL_regex_pad = AvARRAY( PL_regex_padav );
#endif
EOT
    }

    print <<'EOT';
#ifdef CSH
    if (!PL_cshlen) 
      PL_cshlen = strlen(PL_cshname);
#endif

#ifdef ALLOW_PERL_OPTIONS
#define EXTRA_OPTIONS 3
#else
#define EXTRA_OPTIONS 4
#endif /* ALLOW_PERL_OPTIONS */
    New(666, fakeargv, argc + EXTRA_OPTIONS + 1, char *);

    fakeargv[0] = argv[0];
    fakeargv[1] = "-e";
    fakeargv[2] = "";
    options_count = 3;
EOT
    # honour -T
    print <<EOT;
    if( ${^TAINT} ) {
        fakeargv[options_count] = "-T";
        ++options_count;
    }
EOT
    print <<'EOT';
#ifndef ALLOW_PERL_OPTIONS
    fakeargv[options_count] = "--";
    ++options_count;
#endif /* ALLOW_PERL_OPTIONS */
    for (i = 1; i < argc; i++)
	fakeargv[i + options_count - 1] = argv[i];
    fakeargv[argc + options_count - 1] = 0;

    exitstatus = perl_parse(my_perl, xs_init, argc + options_count - 1,
			    fakeargv, NULL);

    if (exitstatus)
	exit( exitstatus );

    TAINT;
EOT

    if( $use_perl_script_name ) {
        my $dollar_0 = $0;
        $dollar_0 =~ s/\\/\\\\/g;
        $dollar_0 = '"' . $dollar_0 . '"';

        print <<EOT;
    if ((tmpgv = gv_fetchpv("0",TRUE, SVt_PV))) {/* $0 */
        tmpsv = GvSV(tmpgv);
        sv_setpv(tmpsv, ${dollar_0});
        SvSETMAGIC(tmpsv);
    }
EOT
    }
    else {
	print <<EOT;
    if ((tmpgv = gv_fetchpv("0",TRUE, SVt_PV))) {/* $0 */
        tmpsv = GvSV(tmpgv);
        sv_setpv(tmpsv, argv[0]);
        SvSETMAGIC(tmpsv);
    }
EOT
    }

    print <<'EOT';
    if ((tmpgv = gv_fetchpv("\030",TRUE, SVt_PV))) {/* $^X */
        tmpsv = GvSV(tmpgv);
#ifdef WIN32
        sv_setpv(tmpsv,"perl.exe");
#else
        sv_setpv(tmpsv,"perl");
#endif
        SvSETMAGIC(tmpsv);
    }

    TAINT_NOT;

    /* PL_main_cv = PL_compcv; */
    PL_compcv = 0;

    exitstatus = perl_init();
    if (exitstatus)
	exit( exitstatus );
    dl_init(aTHX);

    exitstatus = perl_run( my_perl );

    perl_destruct( my_perl );
    perl_free( my_perl );

    PERL_SYS_TERM();

    exit( exitstatus );
}

/* yanked from perl.c */
static void
xs_init(pTHX)
{
    char *file = __FILE__;
    dTARG;
    dSP;
EOT
    print "\n#ifdef USE_DYNAMIC_LOADING";
    print qq/\n\tnewXS("DynaLoader::boot_DynaLoader", boot_DynaLoader, file);/;
    print "\n#endif\n" ;
    # delete $xsub{'DynaLoader'}; 
    delete $xsub{'UNIVERSAL'}; 
    print("/* bootstrapping code*/\n\tSAVETMPS;\n");
    print("\ttarg=sv_newmortal();\n");
    print "#ifdef USE_DYNAMIC_LOADING\n";
    print "\tPUSHMARK(sp);\n";
    print qq/\tXPUSHp("DynaLoader",strlen("DynaLoader"));\n/;
    print qq/\tPUTBACK;\n/;
    print "\tboot_DynaLoader(aTHX_ NULL);\n";
    print qq/\tSPAGAIN;\n/;
    print "#endif\n";
    foreach my $stashname (keys %xsub){
	if ($xsub{$stashname} !~ m/Dynamic/ ) {
	   my $stashxsub=$stashname;
	   $stashxsub  =~ s/::/__/g; 
	   print "\tPUSHMARK(sp);\n";
	   print qq/\tXPUSHp("$stashname",strlen("$stashname"));\n/;
	   print qq/\tPUTBACK;\n/;
	   print "\tboot_$stashxsub(aTHX_ NULL);\n";
	   print qq/\tSPAGAIN;\n/;
	}   
    }
    print("\tFREETMPS;\n/* end bootstrapping code */\n");
    print "}\n";
    
print <<'EOT';
static void
dl_init(pTHX)
{
    char *file = __FILE__;
    dTARG;
    dSP;
EOT
    print("/* Dynamicboot strapping code*/\n\tSAVETMPS;\n");
    print("\ttarg=sv_newmortal();\n");
    foreach my $stashname (@DynaLoader::dl_modules) {
	warn "Loaded $stashname\n";
	if (exists($xsub{$stashname}) && $xsub{$stashname} =~ m/Dynamic/) {
  	   my $stashxsub=$stashname;
	   $stashxsub  =~ s/::/__/g; 
   	   print "\tPUSHMARK(sp);\n";
   	   print qq/\tXPUSHp("$stashname",/,length($stashname),qq/);\n/;
	   print qq/\tPUTBACK;\n/;
           print "#ifdef USE_DYNAMIC_LOADING\n";
	   warn "bootstrapping $stashname added to xs_init\n";
           if( $xsub{$stashname} eq 'Dynamic' ) {
              print qq/\tperl_call_method("bootstrap",G_DISCARD);\n/;
           }
           else {
              print qq/\tperl_call_pv("XSLoader::load",G_DISCARD);\n/;
           }
           print "#else\n";
	   print "\tboot_$stashxsub(aTHX_ NULL);\n";
           print "#endif\n";
	   print qq/\tSPAGAIN;\n/;
	}   
    }
    print("\tFREETMPS;\n/* end Dynamic bootstrapping code */\n");
    print "}\n";
}
sub dump_symtable {
    # For debugging
    my ($sym, $val);
    warn "----Symbol table:\n";
    while (($sym, $val) = each %symtable) {
	warn "$sym => $val\n";
    }
    warn "---End of symbol table\n";
}

sub save_object {
    my $sv;
    foreach $sv (@_) {
	svref_2object($sv)->save;
    }
}       

sub Dummy_BootStrap { }            

sub B::GV::savecv 
{
 my $gv = shift;
 my $package=$gv->STASH->NAME;
 my $name = $gv->NAME;
 my $cv = $gv->CV;
 my $sv = $gv->SV;
 my $av = $gv->AV;
 my $hv = $gv->HV;

 my $fullname = $gv->STASH->NAME . "::" . $gv->NAME;

 # We may be looking at this package just because it is a branch in the 
 # symbol table which is on the path to a package which we need to save
 # e.g. this is 'Getopt' and we need to save 'Getopt::Long'
 # 
 return unless ($unused_sub_packages{$package});
 return unless ($$cv || $$av || $$sv || $$hv);
 $gv->save;
}

sub mark_package
{    
 my $package = shift;
 unless ($unused_sub_packages{$package})
  {    
   no strict 'refs';
   $unused_sub_packages{$package} = 1;
   if (defined @{$package.'::ISA'})
    {
     foreach my $isa (@{$package.'::ISA'}) 
      {
       if ($isa eq 'DynaLoader')
        {
         unless (defined(&{$package.'::bootstrap'}))
          {                    
           warn "Forcing bootstrap of $package\n";
           eval { $package->bootstrap }; 
          }
        }
#      else
        {
         unless ($unused_sub_packages{$isa})
          {
           warn "$isa saved (it is in $package\'s \@ISA)\n";
           mark_package($isa);
          }
        }
      }
    }
  }
 return 1;
}
     
sub should_save
{
 no strict qw(vars refs);
 my $package = shift;
 $package =~ s/::$//;
 return $unused_sub_packages{$package} = 0 if ($package =~ /::::/);  # skip ::::ISA::CACHE etc.
 # warn "Considering $package\n";#debug
 foreach my $u (grep($unused_sub_packages{$_},keys %unused_sub_packages)) 
  {  
   # If this package is a prefix to something we are saving, traverse it 
   # but do not mark it for saving if it is not already
   # e.g. to get to Getopt::Long we need to traverse Getopt but need
   # not save Getopt
   return 1 if ($u =~ /^$package\:\:/);
  }
 if (exists $unused_sub_packages{$package})
  {
   # warn "Cached $package is ".$unused_sub_packages{$package}."\n"; 
   delete_unsaved_hashINC($package) unless  $unused_sub_packages{$package} ;
   return $unused_sub_packages{$package}; 
  }
 # Omit the packages which we use (and which cause grief
 # because of fancy "goto &$AUTOLOAD" stuff).
 # XXX Surely there must be a nicer way to do this.
 if ($package eq "FileHandle" || $package eq "Config" || 
     $package eq "SelectSaver" || $package =~/^(B|IO)::/) 
  {
   delete_unsaved_hashINC($package);
   return $unused_sub_packages{$package} = 0;
  }
 # Now see if current package looks like an OO class this is probably too strong.
 foreach my $m (qw(new DESTROY TIESCALAR TIEARRAY TIEHASH TIEHANDLE)) 
  {
   if (UNIVERSAL::can($package, $m))
    {
     warn "$package has method $m: saving package\n";#debug
     return mark_package($package);
    }
  }
 delete_unsaved_hashINC($package);
 return $unused_sub_packages{$package} = 0;
}
sub delete_unsaved_hashINC{
	my $packname=shift;
	$packname =~ s/\:\:/\//g;
	$packname .= '.pm';
#	warn "deleting $packname" if $INC{$packname} ;# debug
	delete $INC{$packname};
}
sub walkpackages 
{
 my ($symref, $recurse, $prefix) = @_;
 my $sym;
 my $ref;
 no strict 'vars';
 $prefix = '' unless defined $prefix;
 while (($sym, $ref) = each %$symref) 
  {             
   local(*glob);
   *glob = $ref;
   if ($sym =~ /::$/) 
    {
     $sym = $prefix . $sym;
     if ($sym ne "main::" && $sym ne "<none>::" && &$recurse($sym)) 
      {
       walkpackages(\%glob, $recurse, $sym);
      }
    } 
  }
}


sub save_unused_subs 
{
 no strict qw(refs);
 &descend_marked_unused;
 warn "Prescan\n";
 walkpackages(\%{"main::"}, sub { should_save($_[0]); return 1 });
 warn "Saving methods\n";
 walksymtable(\%{"main::"}, "savecv", \&should_save);
}

sub save_context
{
 my $curpad_nam = (comppadlist->ARRAY)[0]->save;
 my $curpad_sym = (comppadlist->ARRAY)[1]->save;
 my $inc_hv     = svref_2object(\%INC)->save;
 my $inc_av     = svref_2object(\@INC)->save;
 my $amagic_generate= amagic_generation;          
 $init->add(   "PL_curpad = AvARRAY($curpad_sym);",
	       "GvHV(PL_incgv) = $inc_hv;",
	       "GvAV(PL_incgv) = $inc_av;",
               "av_store(CvPADLIST(PL_main_cv),0,SvREFCNT_inc($curpad_nam));",
               "av_store(CvPADLIST(PL_main_cv),1,SvREFCNT_inc($curpad_sym));",
  		"PL_amagic_generation= $amagic_generate;" );
}

sub descend_marked_unused {
    foreach my $pack (keys %unused_sub_packages)
    {
    	mark_package($pack);
    }
}
 
sub save_main {
    # this is mainly for the test suite
    my $warner = $SIG{__WARN__};
    local $SIG{__WARN__} = sub { print STDERR @_ };

    warn "Starting compile\n";
    warn "Walking tree\n";
    seek(STDOUT,0,0); #exclude print statements in BEGIN{} into output
    walkoptree(main_root, "save");
    warn "done main optree, walking symtable for extras\n" if $debug_cv;
    save_unused_subs();
    # XSLoader was used, force saving of XSLoader::load
    if( $use_xsloader ) {
        my $cv = svref_2object( \&XSLoader::load );
        $cv->save;
    }
    # save %SIG ( in case it was set in a BEGIN block )
    if( $save_sig ) {
        local $SIG{__WARN__} = $warner;
        $init->no_split;
        $init->add("{", "\tHV* hv = get_hv(\"main::SIG\",1);" );
        foreach my $k ( keys %SIG ) {
            next unless ref $SIG{$k};
            my $cv = svref_2object( \$SIG{$k} );
            my $sv = $cv->save;
            $init->add('{',sprintf 'SV* sv = (SV*)%s;', $sv );
            $init->add(sprintf("\thv_store(hv, %s, %u, %s, %s);",
                               cstring($k),length(pack "a*",$k),
                               'sv', hash($k)));
            $init->add('mg_set(sv);','}');
        }
        $init->add('}');
        $init->split;
    }
    # honour -w
    $init->add( sprintf "    PL_dowarn = ( %s ) ? G_WARN_ON : G_WARN_OFF;", $^W );
    #
    my $init_av = init_av->save;
    my $end_av = end_av->save;
    $init->add(sprintf("PL_main_root = s\\_%x;", ${main_root()}),
	       sprintf("PL_main_start = s\\_%x;", ${main_start()}),
              "PL_initav = (AV *) $init_av;",
              "PL_endav = (AV*) $end_av;");
    save_context();
    # init op addrs ( must be the last action, otherwise
    # some ops might not be initialized
    if( $optimize_ppaddr ) {
        foreach my $i ( @op_sections ) {
            my $section = $$i;
            next unless $section->index >= 0;
            init_op_addr( $section->name, $section->index + 1);
        }
    }
    init_op_warn( $copsect->name, $copsect->index + 1)
      if $optimize_warn_sv && $copsect->index >= 0;

    warn "Writing output\n";
    output_boilerplate();
    print "\n";
    output_all("perl_init");
    print "\n";
    output_main();
}

sub init_sections {
    my @sections = (decl => \$decl, sym => \$symsect,
		    binop => \$binopsect, condop => \$condopsect,
		    cop => \$copsect, padop => \$padopsect,
		    listop => \$listopsect, logop => \$logopsect,
		    loop => \$loopsect, op => \$opsect, pmop => \$pmopsect,
		    pvop => \$pvopsect, svop => \$svopsect, unop => \$unopsect,
		    sv => \$svsect, xpv => \$xpvsect, xpvav => \$xpvavsect,
		    xpvhv => \$xpvhvsect, xpvcv => \$xpvcvsect,
		    xpviv => \$xpvivsect, xpvnv => \$xpvnvsect,
		    xpvmg => \$xpvmgsect, xpvlv => \$xpvlvsect,
		    xrv => \$xrvsect, xpvbm => \$xpvbmsect,
		    xpvio => \$xpviosect);
    my ($name, $sectref);
    while (($name, $sectref) = splice(@sections, 0, 2)) {
	$$sectref = new B::C::Section $name, \%symtable, 0;
    }
    $init = new B::C::InitSection 'init', \%symtable, 0;
}

sub mark_unused
{
 my ($arg,$val) = @_;
 $unused_sub_packages{$arg} = $val;
}

sub compile {
    my @options = @_;
    my ($option, $opt, $arg);
    my @eval_at_startup;
    my %option_map = ( 'cog' => \$pv_copy_on_grow,
                       'save-data' => \$save_data_fh,
                       'ppaddr' => \$optimize_ppaddr,
                       'warn-sv' => \$optimize_warn_sv,
                       'use-script-name' => \$use_perl_script_name,
                       'save-sig-hash' => \$save_sig,
                     );
    my %optimization_map = ( 0 => [ qw() ], # special case
                             1 => [ qw(-fcog) ],
                             2 => [ qw(-fwarn-sv -fppaddr) ],
                           );
  OPTION:
    while ($option = shift @options) {
	if ($option =~ /^-(.)(.*)/) {
	    $opt = $1;
	    $arg = $2;
	} else {
	    unshift @options, $option;
	    last OPTION;
	}
	if ($opt eq "-" && $arg eq "-") {
	    shift @options;
	    last OPTION;
	}
	if ($opt eq "w") {
	    $warn_undefined_syms = 1;
	} elsif ($opt eq "D") {
	    $arg ||= shift @options;
	    foreach $arg (split(//, $arg)) {
		if ($arg eq "o") {
		    B->debug(1);
		} elsif ($arg eq "c") {
		    $debug_cops = 1;
		} elsif ($arg eq "A") {
		    $debug_av = 1;
		} elsif ($arg eq "C") {
		    $debug_cv = 1;
		} elsif ($arg eq "M") {
		    $debug_mg = 1;
		} else {
		    warn "ignoring unknown debug option: $arg\n";
		}
	    }
	} elsif ($opt eq "o") {
	    $arg ||= shift @options;
	    open(STDOUT, ">$arg") or return "$arg: $!\n";
	} elsif ($opt eq "v") {
	    $verbose = 1;
	} elsif ($opt eq "u") {
	    $arg ||= shift @options;
	    mark_unused($arg,undef);
	} elsif ($opt eq "f") {
	    $arg ||= shift @options;
            $arg =~ m/(no-)?(.*)/;
            my $no = defined($1) && $1 eq 'no-';
            $arg = $no ? $2 : $arg;
            if( exists $option_map{$arg} ) {
                ${$option_map{$arg}} = !$no;
            } else {
                die "Invalid optimization '$arg'";
            }
	} elsif ($opt eq "O") {
	    $arg = 1 if $arg eq "";
            my @opt;
            foreach my $i ( 1 .. $arg ) {
                push @opt, @{$optimization_map{$i}}
                    if exists $optimization_map{$i};
            }
            unshift @options, @opt;
        } elsif ($opt eq "e") {
            push @eval_at_startup, $arg;
	} elsif ($opt eq "l") {
	    $max_string_len = $arg;
	}
    }
    init_sections();
    foreach my $i ( @eval_at_startup ) {
        $init->add_eval( $i );
    }
    if (@options) {
	return sub {
	    my $objname;
	    foreach $objname (@options) {
		eval "save_object(\\$objname)";
	    }
	    output_all();
	}
    } else {
	return sub { save_main() };
    }
}

1;

__END__

=head1 NAME

B::C - Perl compiler's C backend

=head1 SYNOPSIS

	perl -MO=C[,OPTIONS] foo.pl

=head1 DESCRIPTION

This compiler backend takes Perl source and generates C source code
corresponding to the internal structures that perl uses to run
your program. When the generated C source is compiled and run, it
cuts out the time which perl would have taken to load and parse
your program into its internal semi-compiled form. That means that
compiling with this backend will not help improve the runtime
execution speed of your program but may improve the start-up time.
Depending on the environment in which your program runs this may be
either a help or a hindrance.

=head1 OPTIONS

If there are any non-option arguments, they are taken to be
names of objects to be saved (probably doesn't work properly yet).
Without extra arguments, it saves the main program.

=over 4

=item B<-ofilename>

Output to filename instead of STDOUT

=item B<-v>

Verbose compilation (currently gives a few compilation statistics).

=item B<-->

Force end of options

=item B<-uPackname>

Force apparently unused subs from package Packname to be compiled.
This allows programs to use eval "foo()" even when sub foo is never
seen to be used at compile time. The down side is that any subs which
really are never used also have code generated. This option is
necessary, for example, if you have a signal handler foo which you
initialise with C<$SIG{BAR} = "foo">.  A better fix, though, is just
to change it to C<$SIG{BAR} = \&foo>. You can have multiple B<-u>
options. The compiler tries to figure out which packages may possibly
have subs in which need compiling but the current version doesn't do
it very well. In particular, it is confused by nested packages (i.e.
of the form C<A::B>) where package C<A> does not contain any subs.

=item B<-D>

Debug options (concatenated or separate flags like C<perl -D>).

=item B<-Do>

OPs, prints each OP as it's processed

=item B<-Dc>

COPs, prints COPs as processed (incl. file & line num)

=item B<-DA>

prints AV information on saving

=item B<-DC>

prints CV information on saving

=item B<-DM>

prints MAGIC information on saving

=item B<-f>

Force options/optimisations on or off one at a time. You can explicitly
disable an option using B<-fno-option>. All options default to
B<disabled>.

=over 4

=item B<-fcog>

Copy-on-grow: PVs declared and initialised statically.

=item B<-fsave-data>

Save package::DATA filehandles ( only available with PerlIO ).

=item B<-fppaddr>

Optimize the initialization of op_ppaddr.

=item B<-fwarn-sv>

Optimize the initialization of cop_warnings.

=item B<-fuse-script-name>

Use the script name instead of the program name as $0.

=item B<-fsave-sig-hash>

Save compile-time modifications to the %SIG hash.

=back

=item B<-On>

Optimisation level (n = 0, 1, 2, ...). B<-O> means B<-O1>.

=over 4

=item B<-O0>

Disable all optimizations.

=item B<-O1>

Enable B<-fcog>.

=item B<-O2>

Enable B<-fppaddr>, B<-fwarn-sv>.

=back

=item B<-llimit>

Some C compilers impose an arbitrary limit on the length of string
constants (e.g. 2048 characters for Microsoft Visual C++).  The
B<-llimit> options tells the C backend not to generate string literals
exceeding that limit.

=back

=head1 EXAMPLES

    perl -MO=C,-ofoo.c foo.pl
    perl cc_harness -o foo foo.c

Note that C<cc_harness> lives in the C<B> subdirectory of your perl
library directory. The utility called C<perlcc> may also be used to
help make use of this compiler.

    perl -MO=C,-v,-DcA,-l2048 bar.pl > /dev/null

=head1 BUGS

Plenty. Current status: experimental.

=head1 AUTHOR

Malcolm Beattie, C<mbeattie@sable.ox.ac.uk>

=cut