2 # Copyright (C) 2000-2003 Stephen McCamant. All rights reserved.
3 # This program is free software; you can redistribute and/or modify it
4 # under the same terms as Perl itself.
6 # Note: we need to keep track of how many use declarations/BEGIN
7 # blocks this module uses, so we can avoid printing them when user
8 # asks for the BEGIN blocks in her program. Update the comments and
9 # the count in concise_specials if you add or delete one. The
10 # -MO=Concise counts as use #1.
13 use warnings; # uses #3 and #4, since warnings uses Carp
15 use Exporter (); # use #5
17 our $VERSION = "0.996";
18 our @ISA = qw(Exporter);
19 our @EXPORT_OK = qw( set_style set_style_standard add_callback
20 concise_subref concise_cv concise_main
21 add_style walk_output compile reset_sequence );
23 ( io => [qw( walk_output compile reset_sequence )],
24 style => [qw( add_style set_style_standard )],
25 cb => [qw( add_callback )],
26 mech => [qw( concise_subref concise_cv concise_main )], );
29 use B qw(class ppname main_start main_root main_cv cstring svref_2object
30 SVf_IOK SVf_NOK SVf_POK SVf_IVisUV SVf_FAKE OPf_KIDS OPf_SPECIAL
31 CVf_ANON PAD_FAKELEX_ANON PAD_FAKELEX_MULTI SVf_ROK);
35 ["(?(#label =>\n)?)(*( )*)#class (#addr) #name (?([#targ])?) "
36 . "#svclass~(?((#svaddr))?)~#svval~(?(label \"#coplabel\")?)\n",
37 "(*( )*)goto #class (#addr)\n",
40 ["#hyphseq2 (*( (x( ;)x))*)<#classsym> #exname#arg(?([#targarglife])?)"
41 . "~#flags(?(/#private)?)(?(:#hints)?)(x(;~->#next)x)\n"
42 , " (*( )*) goto #seq\n",
43 "(?(<#seq>)?)#exname#arg(?([#targarglife])?)"],
45 ["(x(;(*( )*))x)#noise#arg(?([#targarg])?)(x( ;\n)x)",
47 "(?(#seq)?)#noise#arg(?([#targarg])?)"],
49 ["#class (#addr)\n\top_next\t\t#nextaddr\n\t(?(op_other\t#otheraddr\n\t)?)"
50 . "op_sibling\t#sibaddr\n\t"
51 . "op_ppaddr\tPL_ppaddr[OP_#NAME]\n\top_type\t\t#typenum\n"
52 . "\top_flags\t#flagval\n\top_private\t#privval\t#hintsval\n"
53 . "(?(\top_first\t#firstaddr\n)?)(?(\top_last\t\t#lastaddr\n)?)"
54 . "(?(\top_sv\t\t#svaddr\n)?)",
57 "env" => [$ENV{B_CONCISE_FORMAT}, $ENV{B_CONCISE_GOTO_FORMAT},
58 $ENV{B_CONCISE_TREE_FORMAT}],
61 # Renderings, ie how Concise prints, is controlled by these vars
63 our $stylename; # selects current style from %style
64 my $order = "basic"; # how optree is walked & printed: basic, exec, tree
66 # rendering mechanics:
67 # these 'formats' are the line-rendering templates
68 # they're updated from %style when $stylename changes
69 my ($format, $gotofmt, $treefmt);
72 my $base = 36; # how <sequence#> is displayed
73 my $big_endian = 1; # more <sequence#> display
74 my $tree_style = 0; # tree-order details
75 my $banner = 1; # print banner before optree is traversed
76 my $do_main = 0; # force printing of main routine
77 my $show_src; # show source code
79 # another factor: can affect all styles!
80 our @callbacks; # allow external management
82 set_style_standard("concise");
88 ($format, $gotofmt, $treefmt) = @_;
89 #warn "set_style: deprecated, use set_style_standard instead\n"; # someday
90 die "expecting 3 style-format args\n" unless @_ == 3;
94 my ($newstyle,@args) = @_;
95 die "style '$newstyle' already exists, choose a new name\n"
96 if exists $style{$newstyle};
97 die "expecting 3 style-format args\n" unless @args == 3;
98 $style{$newstyle} = [@args];
99 $stylename = $newstyle; # update rendering state
102 sub set_style_standard {
103 ($stylename) = @_; # update rendering state
104 die "err: style '$stylename' unknown\n" unless exists $style{$stylename};
105 set_style(@{$style{$stylename}});
112 # output handle, used with all Concise-output printing
113 our $walkHandle; # public for your convenience
114 BEGIN { $walkHandle = \*STDOUT }
116 sub walk_output { # updates $walkHandle
118 return $walkHandle unless $handle; # allow use as accessor
120 if (ref $handle eq 'SCALAR') {
122 die "no perlio in this build, can't call walk_output (\\\$scalar)\n"
123 unless $Config::Config{useperlio};
124 # in 5.8+, open(FILEHANDLE,MODE,REFERENCE) writes to string
125 open my $tmp, '>', $handle; # but cant re-set existing STDOUT
126 $walkHandle = $tmp; # so use my $tmp as intermediate var
129 my $iotype = ref $handle;
130 die "expecting argument/object that can print\n"
131 unless $iotype eq 'GLOB' or $iotype and $handle->can('print');
132 $walkHandle = $handle;
136 my($order, $coderef, $name) = @_;
137 my $codeobj = svref_2object($coderef);
139 return concise_stashref(@_)
140 unless ref($codeobj) =~ '^B::(?:CV|FM)\z';
141 concise_cv_obj($order, $codeobj, $name);
144 sub concise_stashref {
147 foreach my $k (sort keys %$h) {
148 next unless defined $h->{$k};
150 my $coderef = *s{CODE} or next;
152 print "FUNC: ", *s, "\n";
153 my $codeobj = svref_2object($coderef);
154 next unless ref $codeobj eq 'B::CV';
155 eval { concise_cv_obj($order, $codeobj, $k) };
156 warn "err $@ on $codeobj" if $@;
160 # This should have been called concise_subref, but it was exported
161 # under this name in versions before 0.56
162 *concise_cv = \&concise_subref;
165 my ($order, $cv, $name) = @_;
166 # name is either a string, or a CODE ref (copy of $cv arg??)
170 if (ref($cv->XSUBANY) =~ /B::(\w+)/) {
171 print $walkHandle "$name is a constant sub, optimized to a $1\n";
175 print $walkHandle "$name is XS code\n";
178 if (class($cv->START) eq "NULL") {
180 if (ref $name eq 'CODE') {
181 print $walkHandle "coderef $name has no START\n";
183 elsif (exists &$name) {
184 print $walkHandle "$name exists in stash, but has no START\n";
187 print $walkHandle "$name not in symbol table\n";
191 sequence($cv->START);
192 if ($order eq "exec") {
193 walk_exec($cv->START);
195 elsif ($order eq "basic") {
196 # walk_topdown($cv->ROOT, sub { $_[0]->concise($_[1]) }, 0);
197 my $root = $cv->ROOT;
198 unless (ref $root eq 'B::NULL') {
199 walk_topdown($root, sub { $_[0]->concise($_[1]) }, 0);
201 print $walkHandle "B::NULL encountered doing ROOT on $cv. avoiding disaster\n";
204 print $walkHandle tree($cv->ROOT, 0);
210 sequence(main_start);
212 if ($order eq "exec") {
213 return if class(main_start) eq "NULL";
214 walk_exec(main_start);
215 } elsif ($order eq "tree") {
216 return if class(main_root) eq "NULL";
217 print $walkHandle tree(main_root, 0);
218 } elsif ($order eq "basic") {
219 return if class(main_root) eq "NULL";
220 walk_topdown(main_root,
221 sub { $_[0]->concise($_[1]) }, 0);
225 sub concise_specials {
226 my($name, $order, @cv_s) = @_;
228 if ($name eq "BEGIN") {
229 splice(@cv_s, 0, 8); # skip 7 BEGIN blocks in this file. NOW 8 ??
230 } elsif ($name eq "CHECK") {
231 pop @cv_s; # skip the CHECK block that calls us
234 print $walkHandle "$name $i:\n";
236 concise_cv_obj($order, $cv, $name);
240 my $start_sym = "\e(0"; # "\cN" sometimes also works
241 my $end_sym = "\e(B"; # "\cO" respectively
243 my @tree_decorations =
244 ([" ", "--", "+-", "|-", "| ", "`-", "-", 1],
245 [" ", "-", "+", "+", "|", "`", "", 0],
246 [" ", map("$start_sym$_$end_sym", "qq", "wq", "tq", "x ", "mq", "q"), 1],
247 [" ", map("$start_sym$_$end_sym", "q", "w", "t", "x", "m"), "", 0],
250 my @render_packs; # collect -stash=<packages>
253 # set rendering state from options and args
256 @options = grep(/^-/, @_);
257 @args = grep(!/^-/, @_);
259 for my $o (@options) {
261 if ($o eq "-basic") {
263 } elsif ($o eq "-exec") {
265 } elsif ($o eq "-tree") {
269 elsif ($o eq "-compact") {
271 } elsif ($o eq "-loose") {
273 } elsif ($o eq "-vt") {
275 } elsif ($o eq "-ascii") {
279 elsif ($o =~ /^-base(\d+)$/) {
281 } elsif ($o eq "-bigendian") {
283 } elsif ($o eq "-littleendian") {
286 # miscellaneous, presentation
287 elsif ($o eq "-nobanner") {
289 } elsif ($o eq "-banner") {
292 elsif ($o eq "-main") {
294 } elsif ($o eq "-nomain") {
296 } elsif ($o eq "-src") {
299 elsif ($o =~ /^-stash=(.*)/) {
302 if (! %{$pkg.'::'}) {
306 if (!$Config::Config{usedl}
307 && keys %{$pkg.'::'} == 1
308 && $pkg->can('bootstrap')) {
309 # It is something that we're statically linked to, but hasn't
314 push @render_packs, $pkg;
317 elsif (exists $style{substr($o, 1)}) {
318 $stylename = substr($o, 1);
319 set_style_standard($stylename);
321 warn "Option $o unrecognized";
328 my (@args) = compileOpts(@_);
330 my @newargs = compileOpts(@_); # accept new rendering options
331 warn "disregarding non-options: @newargs\n" if @newargs;
333 for my $objname (@args) {
334 next unless $objname; # skip null args to avoid noisy responses
336 if ($objname eq "BEGIN") {
337 concise_specials("BEGIN", $order,
338 B::begin_av->isa("B::AV") ?
339 B::begin_av->ARRAY : ());
340 } elsif ($objname eq "INIT") {
341 concise_specials("INIT", $order,
342 B::init_av->isa("B::AV") ?
343 B::init_av->ARRAY : ());
344 } elsif ($objname eq "CHECK") {
345 concise_specials("CHECK", $order,
346 B::check_av->isa("B::AV") ?
347 B::check_av->ARRAY : ());
348 } elsif ($objname eq "UNITCHECK") {
349 concise_specials("UNITCHECK", $order,
350 B::unitcheck_av->isa("B::AV") ?
351 B::unitcheck_av->ARRAY : ());
352 } elsif ($objname eq "END") {
353 concise_specials("END", $order,
354 B::end_av->isa("B::AV") ?
355 B::end_av->ARRAY : ());
358 # convert function names to subrefs
360 print $walkHandle "B::Concise::compile($objname)\n"
362 concise_subref($order, ($objname)x2);
365 $objname = "main::" . $objname unless $objname =~ /::/;
367 my $glob = \*$objname;
368 unless (*$glob{CODE} || *$glob{FORMAT}) {
369 print $walkHandle "$objname:\n" if $banner;
370 print $walkHandle "err: unknown function ($objname)\n";
373 if (my $objref = *$glob{CODE}) {
374 print $walkHandle "$objname:\n" if $banner;
375 concise_subref($order, $objref, $objname);
377 if (my $objref = *$glob{FORMAT}) {
378 print $walkHandle "$objname (FORMAT):\n"
380 concise_subref($order, $objref, $objname);
385 for my $pkg (@render_packs) {
387 concise_stashref($order, \%{$pkg.'::'});
390 if (!@args or $do_main or @render_packs) {
391 print $walkHandle "main program:\n" if $do_main;
392 concise_main($order);
394 return @args; # something
399 my $lastnext; # remembers op-chain, used to insert gotos
401 my %opclass = ('OP' => "0", 'UNOP' => "1", 'BINOP' => "2", 'LOGOP' => "|",
402 'LISTOP' => "@", 'PMOP' => "/", 'SVOP' => "\$", 'GVOP' => "*",
403 'PVOP' => '"', 'LOOP' => "{", 'COP' => ";", 'PADOP' => "#",
404 'METHOP' => '.', UNOP_AUX => '+');
406 no warnings 'qw'; # "Possible attempt to put comments..."; use #7
408 qw'# () sc ( @? 1 $* gv *{ m$ m@ m% m? p/ *$ $ $# & a& pt \\ s\\ rf bl
409 ` *? <> ?? ?/ r/ c/ // qr s/ /c y/ = @= C sC Cp sp df un BM po +1 +I
410 -1 -I 1+ I+ 1- I- ** * i* / i/ %$ i% x + i+ - i- . " << >> < i<
411 > i> <= i, >= i. == i= != i! <? i? s< s> s, s. s= s! s? b& b^ b| -0 -i
412 ! ~ a2 si cs rd sr e^ lg sq in %x %o ab le ss ve ix ri sf FL od ch cy
413 uf lf uc lc qm @ [f [ @[ eh vl ky dl ex % ${ @{ uk pk st jn ) )[ a@
414 a% sl +] -] [- [+ so rv GS GW MS MW .. f. .f && || ^^ ?: &= |= -> s{ s}
415 v} ca wa di rs ;; ; ;d }{ { } {} f{ it {l l} rt }l }n }r dm }g }e ^o
416 ^c ^| ^# um bm t~ u~ ~d DB db ^s se ^g ^r {w }w pf pr ^O ^K ^R ^W ^d ^v
417 ^e ^t ^k t. fc ic fl .s .p .b .c .l .a .h g1 s1 g2 s2 ?. l? -R -W -X -r
418 -w -x -e -o -O -z -s -M -A -C -S -c -b -f -d -p -l -u -g -k -t -T -B cd
419 co cr u. cm ut r. l@ s@ r@ mD uD oD rD tD sD wD cD f$ w$ p$ sh e$ k$ g3
420 g4 s4 g5 s5 T@ C@ L@ G@ A@ S@ Hg Hc Hr Hw Mg Mc Ms Mr Sg Sc So rq do {e
421 e} {t t} g6 G6 6e g7 G7 7e g8 G8 8e g9 G9 9e 6s 7s 8s 9s 6E 7E 8E 9E Pn
422 Pu GP SP EP Gn Gg GG SG EG g0 c$ lk t$ ;s n> // /= CO';
424 my $chars = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
426 sub op_flags { # common flags (see BASOP.op_flags in op.h)
429 push @v, "v" if ($x & 3) == 1;
430 push @v, "s" if ($x & 3) == 2;
431 push @v, "l" if ($x & 3) == 3;
432 push @v, "K" if $x & 4;
433 push @v, "P" if $x & 8;
434 push @v, "R" if $x & 16;
435 push @v, "M" if $x & 32;
436 push @v, "S" if $x & 64;
437 push @v, "*" if $x & 128;
443 return "-" . base_n(-$x) if $x < 0;
445 do { $str .= substr($chars, $x % $base, 1) } while $x = int($x / $base);
446 $str = reverse $str if $big_endian;
462 return "-" if not exists $sequence_num{$$op};
463 return base_n($sequence_num{$$op});
467 my($op, $sub, $level) = @_;
469 if ($op->flags & OPf_KIDS) {
470 for (my $kid = $op->first; $$kid; $kid = $kid->sibling) {
471 walk_topdown($kid, $sub, $level + 1);
474 if (class($op) eq "PMOP") {
475 my $maybe_root = $op->code_list;
476 if ( ref($maybe_root) and $maybe_root->isa("B::OP")
477 and not $op->flags & OPf_KIDS) {
478 walk_topdown($maybe_root, $sub, $level + 1);
480 $maybe_root = $op->pmreplroot;
481 if (ref($maybe_root) and $maybe_root->isa("B::OP")) {
482 # It really is the root of the replacement, not something
483 # else stored here for lack of space elsewhere
484 walk_topdown($maybe_root, $sub, $level + 1);
490 my($ar, $level) = @_;
492 if (ref($l) eq "ARRAY") {
493 walklines($l, $level + 1);
501 my($top, $level) = @_;
504 my @todo = ([$top, \@lines]);
505 while (@todo and my($op, $targ) = @{shift @todo}) {
506 for (; $$op; $op = $op->next) {
507 last if $opsseen{$$op}++;
509 my $name = $op->name;
510 if (class($op) eq "LOGOP") {
513 push @todo, [$op->other, $ar];
514 } elsif ($name eq "subst" and $ {$op->pmreplstart}) {
517 push @todo, [$op->pmreplstart, $ar];
518 } elsif ($name =~ /^enter(loop|iter)$/) {
519 $labels{${$op->nextop}} = "NEXT";
520 $labels{${$op->lastop}} = "LAST";
521 $labels{${$op->redoop}} = "REDO";
525 walklines(\@lines, 0);
528 # The structure of this routine is purposely modeled after op.c's peep()
532 return if class($op) eq "NULL" or exists $sequence_num{$$op};
533 for (; $$op; $op = $op->next) {
534 last if exists $sequence_num{$$op};
535 my $name = $op->name;
536 $sequence_num{$$op} = $seq_max++;
537 if (class($op) eq "LOGOP") {
538 sequence($op->other);
539 } elsif (class($op) eq "LOOP") {
540 sequence($op->redoop);
541 sequence( $op->nextop);
542 sequence($op->lastop);
543 } elsif ($name eq "subst" and $ {$op->pmreplstart}) {
544 sequence($op->pmreplstart);
550 sub fmt_line { # generate text-line for op.
551 my($hr, $op, $text, $level) = @_;
553 $_->($hr, $op, \$text, \$level, $stylename) for @callbacks;
555 return '' if $hr->{SKIP}; # suppress line if a callback said so
556 return '' if $hr->{goto} and $hr->{goto} eq '-'; # no goto nowhere
558 # spec: (?(text1#varText2)?)
559 $text =~ s/\(\?\(([^\#]*?)\#(\w+)([^\#]*?)\)\?\)/
560 $hr->{$2} ? $1.$hr->{$2}.$3 : ""/eg;
562 # spec: (x(exec_text;basic_text)x)
563 $text =~ s/\(x\((.*?);(.*?)\)x\)/$order eq "exec" ? $1 : $2/egs;
566 $text =~ s/\(\*\(([^;]*?)\)\*\)/$1 x $level/egs;
568 # spec: (*(text1;text2)*)
569 $text =~ s/\(\*\((.*?);(.*?)\)\*\)/$1 x ($level - 1) . $2 x ($level>0)/egs;
571 # convert #Var to tag=>val form: Var\t#var
572 $text =~ s/\#([A-Z][a-z]+)(\d+)?/\t\u$1\t\L#$1$2/gs;
575 $text =~ s/\#([a-zA-Z]+)(\d+)/sprintf("%-$2s", $hr->{$1})/eg;
577 $text =~ s/\#([a-zA-Z]+)/$hr->{$1}/eg; # populate #var's
578 $text =~ s/[ \t]*~+[ \t]*/ /g; # squeeze tildes
580 $text = "# $hr->{src}\n$text" if $show_src and $hr->{src};
583 return "$text\n" if $text ne "" and $order ne "tree";
584 return $text; # suppress empty lines
589 # use require rather than use here to avoid disturbing tests that dump
591 require B::Op_private;
595 our %hints; # used to display each COP's op_hints values
597 # strict refs, subs, vars
598 @hints{2,512,1024,32,64,128} = ('$', '&', '*', 'x$', 'x&', 'x*');
599 # integers, locale, bytes
600 @hints{1,4,8,16} = ('i', 'l', 'b');
601 # block scope, localise %^H, $^OPEN (in), $^OPEN (out)
602 @hints{256,131072,262144,524288} = ('{','%','<','>');
603 # overload new integer, float, binary, string, re
604 @hints{4096,8192,16384,32768,65536} = ('I', 'F', 'B', 'S', 'R');
606 @hints{1048576,2097152} = ('T', 'E');
607 # filetest access, UTF-8
608 @hints{4194304,8388608} = ('X', 'U');
613 for my $flag (sort {$b <=> $a} keys %$hash) {
614 if ($hash->{$flag} and $x & $flag and $x >= $flag) {
616 push @s, $hash->{$flag};
620 return join(",", @s);
623 # return a string like 'LVINTRO,1' for the op $name with op_private
628 my $entry = $B::Op_private::bits{$name};
629 return $x ? "$x" : '' unless $entry;
633 for ($bit = 7; $bit >= 0; $bit--) {
634 next unless exists $entry->{$bit};
635 my $e = $entry->{$bit};
636 if (ref($e) eq 'HASH') {
639 my ($bitmin, $bitmax, $bitmask, $enum, $label) =
640 @{$e}{qw(bitmin bitmax bitmask enum label)};
642 next if defined $label && $label eq '-'; # display as raw number
644 my $val = $x & $bitmask;
649 # try to convert numeric $val into symbolic
652 my $ix = shift @enum;
653 my $name = shift @enum;
654 my $label = shift @enum;
661 next if $val eq '0'; # don't display anonymous zero values
662 push @flags, defined $label ? "$label=$val" : $val;
667 my $label = $B::Op_private::labels{$e};
668 next if defined $label && $label eq '-'; # display as raw number
669 if ($x & (1<<$bit)) {
676 push @flags, $x if $x; # display unknown bits numerically
677 return join ",", @flags;
686 my($sv, $hr, $preferpv) = @_;
687 $hr->{svclass} = class($sv);
688 $hr->{svclass} = "UV"
689 if $hr->{svclass} eq "IV" and $sv->FLAGS & SVf_IVisUV;
690 Carp::cluck("bad concise_sv: $sv") unless $sv and $$sv;
691 $hr->{svaddr} = sprintf("%#x", $$sv);
692 if ($hr->{svclass} eq "GV" && $sv->isGV_with_GP()) {
694 my $stash = $gv->STASH;
695 if (class($stash) eq "SPECIAL") {
699 $stash = $stash->NAME;
701 if ($stash eq "main") {
704 $stash = $stash . "::";
706 $hr->{svval} = "*$stash" . $gv->SAFENAME;
707 return "*$stash" . $gv->SAFENAME;
710 while (class($sv) eq "IV" && $sv->FLAGS & SVf_ROK) {
711 $hr->{svval} .= "\\";
715 while (class($sv) eq "RV") {
716 $hr->{svval} .= "\\";
720 if (class($sv) eq "SPECIAL") {
721 $hr->{svval} .= ["Null", "sv_undef", "sv_yes", "sv_no"]->[$$sv];
723 && ($sv->FLAGS & SVf_POK || class($sv) eq "REGEXP")) {
724 $hr->{svval} .= cstring($sv->PV);
725 } elsif ($sv->FLAGS & SVf_NOK) {
726 $hr->{svval} .= $sv->NV;
727 } elsif ($sv->FLAGS & SVf_IOK) {
728 $hr->{svval} .= $sv->int_value;
729 } elsif ($sv->FLAGS & SVf_POK || class($sv) eq "REGEXP") {
730 $hr->{svval} .= cstring($sv->PV);
731 } elsif (class($sv) eq "HV") {
732 $hr->{svval} .= 'HASH';
735 $hr->{svval} = 'undef' unless defined $hr->{svval};
736 my $out = $hr->{svclass};
737 return $out .= " $hr->{svval}" ;
745 if ($fullnm eq '-e') {
746 $srclines{$fullnm} = [ $fullnm, "-src not supported for -e" ];
749 open (my $fh, '<', $fullnm)
750 or warn "# $fullnm: $!, (chdirs not supported by this feature yet)\n"
754 unshift @l, $fullnm; # like @{_<$fullnm} in debug, array starts at 1
755 $srclines{$fullnm} = \@l;
759 my ($op, $level, $format) = @_;
761 $h{exname} = $h{name} = $op->name;
762 $h{NAME} = uc $h{name};
763 $h{class} = class($op);
764 $h{extarg} = $h{targ} = $op->targ;
765 $h{extarg} = "" unless $h{extarg};
766 $h{privval} = $op->private;
767 # for null ops, targ holds the old type
768 my $origname = $h{name} eq "null" && $h{targ}
769 ? substr(ppname($h{targ}), 3)
771 $h{private} = private_flags($origname, $op->private);
773 $h{private} &&= "$h{private},";
774 $h{private} .= "FOLD";
777 if ($h{name} ne $origname) { # a null op
778 $h{exname} = "ex-$origname";
780 } elsif ($h{private} =~ /\bREFC\b/) {
781 # targ holds a reference count
782 my $refs = "ref" . ($h{targ} != 1 ? "s" : "");
783 $h{targarglife} = $h{targarg} = "$h{targ} $refs";
785 my $count = $h{name} eq 'padrange'
786 ? ($op->private & $B::Op_private::defines{'OPpPADRANGE_COUNTMASK'})
788 my (@targarg, @targarglife);
789 for my $i (0..$count-1) {
790 my ($targarg, $targarglife);
791 my $padname = (($curcv->PADLIST->ARRAY)[0]->ARRAY)[$h{targ}+$i];
792 if (defined $padname and class($padname) ne "SPECIAL" and
795 $targarg = $padname->PVX;
796 if ($padname->FLAGS & SVf_FAKE) {
797 # These changes relate to the jumbo closure fix.
798 # See changes 19939 and 20005
801 if $padname->PARENT_FAKELEX_FLAGS & PAD_FAKELEX_ANON;
803 if $padname->PARENT_FAKELEX_FLAGS & PAD_FAKELEX_MULTI;
804 $fake .= ':' . $padname->PARENT_PAD_INDEX
805 if $curcv->CvFLAGS & CVf_ANON;
806 $targarglife = "$targarg:FAKE:$fake";
809 my $intro = $padname->COP_SEQ_RANGE_LOW - $cop_seq_base;
810 my $finish = int($padname->COP_SEQ_RANGE_HIGH) - $cop_seq_base;
811 $finish = "end" if $finish == 999999999 - $cop_seq_base;
812 $targarglife = "$targarg:$intro,$finish";
815 $targarglife = $targarg = "t" . ($h{targ}+$i);
817 push @targarg, $targarg;
818 push @targarglife, $targarglife;
820 $h{targarg} = join '; ', @targarg;
821 $h{targarglife} = join '; ', @targarglife;
824 $h{svclass} = $h{svaddr} = $h{svval} = "";
825 if ($h{class} eq "PMOP") {
827 my $precomp = $op->precomp;
828 if (defined $precomp) {
829 $precomp = cstring($precomp); # Escape literal control sequences
830 $precomp = "/$precomp/";
834 if ($op->name eq 'subst') {
835 if (class($op->pmreplstart) ne "NULL") {
837 $extra = " replstart->" . seq($op->pmreplstart);
840 elsif ($op->name eq 'pushre') {
841 # with C<@stash_array = split(/pat/, str);>,
842 # *stash_array is stored in /pat/'s pmreplroot.
843 my $gv = $op->pmreplroot;
845 # threaded: the value is actually a pad offset for where
846 # the GV is kept (op_pmtargetoff)
848 $gv = (($curcv->PADLIST->ARRAY)[1]->ARRAY)[$gv]->NAME;
852 # unthreaded: its a GV (if it exists)
853 $gv = (ref($gv) eq "B::GV") ? $gv->NAME : undef;
855 $extra = " => \@$gv" if $gv;
857 $h{arg} = "($precomp$extra)";
858 } elsif ($h{class} eq "PVOP" and $h{name} !~ '^transr?\z') {
859 $h{arg} = '("' . $op->pv . '")';
860 $h{svval} = '"' . $op->pv . '"';
861 } elsif ($h{class} eq "COP") {
862 my $label = $op->label;
863 $h{coplabel} = $label;
864 $label = $label ? "$label: " : "";
870 my($stash, $cseq) = ($op->stash->NAME, $op->cop_seq - $cop_seq_base);
871 $h{arg} = "($label$stash $cseq $loc)";
873 fill_srclines($pathnm) unless exists $srclines{$pathnm};
874 # Would love to retain Jim's use of // but this code needs to be
876 my $line = $srclines{$pathnm}[$ln];
877 $line = "-src unavailable under -e" unless defined $line;
878 $h{src} = "$ln: $line";
880 } elsif ($h{class} eq "LOOP") {
881 $h{arg} = "(next->" . seq($op->nextop) . " last->" . seq($op->lastop)
882 . " redo->" . seq($op->redoop) . ")";
883 } elsif ($h{class} eq "LOGOP") {
885 $h{arg} = "(other->" . seq($op->other) . ")";
886 $h{otheraddr} = sprintf("%#x", $ {$op->other});
888 elsif ($h{class} eq "SVOP" or $h{class} eq "PADOP") {
889 unless ($h{name} eq 'aelemfast' and $op->flags & OPf_SPECIAL) {
890 my $idx = ($h{class} eq "SVOP") ? $op->targ : $op->padix;
891 if ($h{class} eq "PADOP" or !${$op->sv}) {
892 my $sv = (($curcv->PADLIST->ARRAY)[1]->ARRAY)[$idx];
893 $h{arg} = "[" . concise_sv($sv, \%h, 0) . "]";
894 $h{targarglife} = $h{targarg} = "";
896 $h{arg} = "(" . concise_sv($op->sv, \%h, 0) . ")";
900 elsif ($h{class} eq "METHOP") {
902 if ($h{name} eq 'method_redir' or $h{name} eq 'method_redir_super') {
903 my $rclass_sv = $op->rclass;
904 $rclass_sv = (($curcv->PADLIST->ARRAY)[1]->ARRAY)[$rclass_sv]
905 unless ref $rclass_sv;
906 $prefix .= 'PACKAGE "'.$rclass_sv->PV.'", ';
908 if ($h{name} ne "method") {
909 if (${$op->meth_sv}) {
910 $h{arg} = "($prefix" . concise_sv($op->meth_sv, \%h, 1) . ")";
912 my $sv = (($curcv->PADLIST->ARRAY)[1]->ARRAY)[$op->targ];
913 $h{arg} = "[$prefix" . concise_sv($sv, \%h, 1) . "]";
914 $h{targarglife} = $h{targarg} = "";
918 elsif ($h{class} eq "UNOP_AUX") {
919 $h{arg} = "(" . $op->string($curcv) . ")";
922 $h{seq} = $h{hyphseq} = seq($op);
923 $h{seq} = "" if $h{seq} eq "-";
925 $h{label} = $labels{$$op};
926 $h{next} = $op->next;
927 $h{next} = (class($h{next}) eq "NULL") ? "(end)" : seq($h{next});
928 $h{nextaddr} = sprintf("%#x", $ {$op->next});
929 $h{sibaddr} = sprintf("%#x", $ {$op->sibling});
930 $h{firstaddr} = sprintf("%#x", $ {$op->first}) if $op->can("first");
931 $h{lastaddr} = sprintf("%#x", $ {$op->last}) if $op->can("last");
933 $h{classsym} = $opclass{$h{class}};
934 $h{flagval} = $op->flags;
935 $h{flags} = op_flags($op->flags);
936 if ($op->can("hints")) {
937 $h{hintsval} = $op->hints;
938 $h{hints} = hints_flags($h{hintsval});
940 $h{hintsval} = $h{hints} = '';
942 $h{addr} = sprintf("%#x", $$op);
943 $h{typenum} = $op->type;
944 $h{noise} = $linenoise[$op->type];
946 return fmt_line(\%h, $op, $format, $level);
950 my($op, $level) = @_;
951 if ($order eq "exec" and $lastnext and $$lastnext != $$op) {
952 # insert a 'goto' line
953 my $synth = {"seq" => seq($lastnext), "class" => class($lastnext),
954 "addr" => sprintf("%#x", $$lastnext),
955 "goto" => seq($lastnext), # simplify goto '-' removal
957 print $walkHandle fmt_line($synth, $op, $gotofmt, $level+1);
959 $lastnext = $op->next;
960 print $walkHandle concise_op($op, $level, $format);
963 # B::OP::terse (see Terse.pm) now just calls this
965 my($op, $level) = @_;
967 # This isn't necessarily right, but there's no easy way to get
968 # from an OP to the right CV. This is a limitation of the
969 # ->terse() interface style, and there isn't much to do about
970 # it. In particular, we can die in concise_op if the main pad
971 # isn't long enough, or has the wrong kind of entries, compared to
972 # the pad a sub was compiled with. The fix for that would be to
973 # make a backwards compatible "terse" format that never even
974 # looked at the pad, just like the old B::Terse. I don't think
975 # that's worth the effort, though.
976 $curcv = main_cv unless $curcv;
978 if ($order eq "exec" and $lastnext and $$lastnext != $$op) {
980 my $h = {"seq" => seq($lastnext), "class" => class($lastnext),
981 "addr" => sprintf("%#x", $$lastnext)};
983 fmt_line($h, $op, $style{"terse"}[1], $level+1);
985 $lastnext = $op->next;
987 concise_op($op, $level, $style{"terse"}[0]);
993 my $style = $tree_decorations[$tree_style];
994 my($space, $single, $kids, $kid, $nokid, $last, $lead, $size) = @$style;
995 my $name = concise_op($op, $level, $treefmt);
996 if (not $op->flags & OPf_KIDS) {
1000 for (my $kid = $op->first; $$kid; $kid = $kid->sibling) {
1001 push @lines, tree($kid, $level+1);
1004 for ($i = $#lines; substr($lines[$i], 0, 1) eq " "; $i--) {
1005 $lines[$i] = $space . $lines[$i];
1008 $lines[$i] = $last . $lines[$i];
1010 if (substr($lines[$i], 0, 1) eq " ") {
1011 $lines[$i] = $nokid . $lines[$i];
1013 $lines[$i] = $kid . $lines[$i];
1016 $lines[$i] = $kids . $lines[$i];
1018 $lines[0] = $single . $lines[0];
1020 return("$name$lead" . shift @lines,
1021 map(" " x (length($name)+$size) . $_, @lines));
1024 # *** Warning: fragile kludge ahead ***
1025 # Because the B::* modules run in the same interpreter as the code
1026 # they're compiling, their presence tends to distort the view we have of
1027 # the code we're looking at. In particular, perl gives sequence numbers
1028 # to COPs. If the program we're looking at were run on its own, this
1029 # would start at 1. Because all of B::Concise and all the modules it
1030 # uses are compiled first, though, by the time we get to the user's
1031 # program the sequence number is already pretty high, which could be
1032 # distracting if you're trying to tell OPs apart. Therefore we'd like to
1033 # subtract an offset from all the sequence numbers we display, to
1034 # restore the simpler view of the world. The trick is to know what that
1035 # offset will be, when we're still compiling B::Concise! If we
1036 # hardcoded a value, it would have to change every time B::Concise or
1037 # other modules we use do. To help a little, what we do here is compile
1038 # a little code at the end of the module, and compute the base sequence
1039 # number for the user's program as being a small offset later, so all we
1040 # have to worry about are changes in the offset.
1042 # [For 5.8.x and earlier perl is generating sequence numbers for all ops,
1043 # and using them to reference labels]
1046 # When you say "perl -MO=Concise -e '$a'", the output should look like:
1048 # 4 <@> leave[t1] vKP/REFC ->(end)
1050 #^ smallest OP sequence number should be 1
1051 # 2 <;> nextstate(main 1 -e:1) v ->3
1052 # ^ smallest COP sequence number should be 1
1053 # - <1> ex-rv2sv vK/1 ->4
1054 # 3 <$> gvsv(*a) s ->4
1056 # If the second of the marked numbers there isn't 1, it means you need
1057 # to update the corresponding magic number in the next line.
1058 # Remember, this needs to stay the last things in the module.
1060 my $cop_seq_mnum = 16;
1061 $cop_seq_base = svref_2object(eval 'sub{0;}')->START->cop_seq + $cop_seq_mnum;
1069 B::Concise - Walk Perl syntax tree, printing concise info about ops
1073 perl -MO=Concise[,OPTIONS] foo.pl
1075 use B::Concise qw(set_style add_callback);
1079 This compiler backend prints the internal OPs of a Perl program's syntax
1080 tree in one of several space-efficient text formats suitable for debugging
1081 the inner workings of perl or other compiler backends. It can print OPs in
1082 the order they appear in the OP tree, in the order they will execute, or
1083 in a text approximation to their tree structure, and the format of the
1084 information displayed is customizable. Its function is similar to that of
1085 perl's B<-Dx> debugging flag or the B<B::Terse> module, but it is more
1086 sophisticated and flexible.
1090 Here's two outputs (or 'renderings'), using the -exec and -basic
1091 (i.e. default) formatting conventions on the same code snippet.
1093 % perl -MO=Concise,-exec -e '$a = $b + 42'
1095 2 <;> nextstate(main 1 -e:1) v
1097 4 <$> const[IV 42] s
1098 * 5 <2> add[t3] sK/2
1101 8 <@> leave[1 ref] vKP/REFC
1103 In this -exec rendering, each opcode is executed in the order shown.
1104 The add opcode, marked with '*', is discussed in more detail.
1106 The 1st column is the op's sequence number, starting at 1, and is
1107 displayed in base 36 by default. Here they're purely linear; the
1108 sequences are very helpful when looking at code with loops and
1111 The symbol between angle brackets indicates the op's type, for
1112 example; <2> is a BINOP, <@> a LISTOP, and <#> is a PADOP, which is
1113 used in threaded perls. (see L</"OP class abbreviations">).
1115 The opname, as in B<'add[t1]'>, may be followed by op-specific
1116 information in parentheses or brackets (ex B<'[t1]'>).
1118 The op-flags (ex B<'sK/2'>) are described in (L</"OP flags
1121 % perl -MO=Concise -e '$a = $b + 42'
1122 8 <@> leave[1 ref] vKP/REFC ->(end)
1124 2 <;> nextstate(main 1 -e:1) v ->3
1125 7 <2> sassign vKS/2 ->8
1126 * 5 <2> add[t1] sK/2 ->6
1127 - <1> ex-rv2sv sK/1 ->4
1128 3 <$> gvsv(*b) s ->4
1129 4 <$> const(IV 42) s ->5
1130 - <1> ex-rv2sv sKRM*/1 ->7
1131 6 <$> gvsv(*a) s ->7
1133 The default rendering is top-down, so they're not in execution order.
1134 This form reflects the way the stack is used to parse and evaluate
1135 expressions; the add operates on the two terms below it in the tree.
1137 Nullops appear as C<ex-opname>, where I<opname> is an op that has been
1138 optimized away by perl. They're displayed with a sequence-number of
1139 '-', because they are not executed (they don't appear in previous
1140 example), they're printed here because they reflect the parse.
1142 The arrow points to the sequence number of the next op; they're not
1143 displayed in -exec mode, for obvious reasons.
1145 Note that because this rendering was done on a non-threaded perl, the
1146 PADOPs in the previous examples are now SVOPs, and some (but not all)
1147 of the square brackets have been replaced by round ones. This is a
1148 subtle feature to provide some visual distinction between renderings
1149 on threaded and un-threaded perls.
1154 Arguments that don't start with a hyphen are taken to be the names of
1155 subroutines or formats to render; if no
1156 such functions are specified, the main
1157 body of the program (outside any subroutines, and not including use'd
1158 or require'd files) is rendered. Passing C<BEGIN>, C<UNITCHECK>,
1159 C<CHECK>, C<INIT>, or C<END> will cause all of the corresponding
1160 special blocks to be printed. Arguments must follow options.
1162 Options affect how things are rendered (ie printed). They're presented
1163 here by their visual effect, 1st being strongest. They're grouped
1164 according to how they interrelate; within each group the options are
1165 mutually exclusive (unless otherwise stated).
1167 =head2 Options for Opcode Ordering
1169 These options control the 'vertical display' of opcodes. The display
1170 'order' is also called 'mode' elsewhere in this document.
1176 Print OPs in the order they appear in the OP tree (a preorder
1177 traversal, starting at the root). The indentation of each OP shows its
1178 level in the tree, and the '->' at the end of the line indicates the
1179 next opcode in execution order. This mode is the default, so the flag
1180 is included simply for completeness.
1184 Print OPs in the order they would normally execute (for the majority
1185 of constructs this is a postorder traversal of the tree, ending at the
1186 root). In most cases the OP that usually follows a given OP will
1187 appear directly below it; alternate paths are shown by indentation. In
1188 cases like loops when control jumps out of a linear path, a 'goto'
1193 Print OPs in a text approximation of a tree, with the root of the tree
1194 at the left and 'left-to-right' order of children transformed into
1195 'top-to-bottom'. Because this mode grows both to the right and down,
1196 it isn't suitable for large programs (unless you have a very wide
1201 =head2 Options for Line-Style
1203 These options select the line-style (or just style) used to render
1204 each opcode, and dictates what info is actually printed into each line.
1210 Use the author's favorite set of formatting conventions. This is the
1215 Use formatting conventions that emulate the output of B<B::Terse>. The
1216 basic mode is almost indistinguishable from the real B<B::Terse>, and the
1217 exec mode looks very similar, but is in a more logical order and lacks
1218 curly brackets. B<B::Terse> doesn't have a tree mode, so the tree mode
1219 is only vaguely reminiscent of B<B::Terse>.
1223 Use formatting conventions in which the name of each OP, rather than being
1224 written out in full, is represented by a one- or two-character abbreviation.
1225 This is mainly a joke.
1229 Use formatting conventions reminiscent of B<B::Debug>; these aren't
1230 very concise at all.
1234 Use formatting conventions read from the environment variables
1235 C<B_CONCISE_FORMAT>, C<B_CONCISE_GOTO_FORMAT>, and C<B_CONCISE_TREE_FORMAT>.
1239 =head2 Options for tree-specific formatting
1245 Use a tree format in which the minimum amount of space is used for the
1246 lines connecting nodes (one character in most cases). This squeezes out
1247 a few precious columns of screen real estate.
1251 Use a tree format that uses longer edges to separate OP nodes. This format
1252 tends to look better than the compact one, especially in ASCII, and is
1257 Use tree connecting characters drawn from the VT100 line-drawing set.
1258 This looks better if your terminal supports it.
1262 Draw the tree with standard ASCII characters like C<+> and C<|>. These don't
1263 look as clean as the VT100 characters, but they'll work with almost any
1264 terminal (or the horizontal scrolling mode of less(1)) and are suitable
1265 for text documentation or email. This is the default.
1269 These are pairwise exclusive, i.e. compact or loose, vt or ascii.
1271 =head2 Options controlling sequence numbering
1277 Print OP sequence numbers in base I<n>. If I<n> is greater than 10, the
1278 digit for 11 will be 'a', and so on. If I<n> is greater than 36, the digit
1279 for 37 will be 'A', and so on until 62. Values greater than 62 are not
1280 currently supported. The default is 36.
1284 Print sequence numbers with the most significant digit first. This is the
1285 usual convention for Arabic numerals, and the default.
1287 =item B<-littleendian>
1289 Print sequence numbers with the least significant digit first. This is
1290 obviously mutually exclusive with bigendian.
1294 =head2 Other options
1300 With this option, the rendering of each statement (starting with the
1301 nextstate OP) will be preceded by the 1st line of source code that
1302 generates it. For example:
1306 2 <;> nextstate(main 1 junk.pl:1) v:{
1307 3 <0> padsv[$i:1,10] vM/LVINTRO
1308 # 3: for $i (0..9) {
1309 4 <;> nextstate(main 3 junk.pl:3) v:{
1313 8 <{> enteriter(next->j last->m redo->9)[$i:1,10] lKS
1315 l <|> and(other->9) vK/1
1317 9 <;> nextstate(main 2 junk.pl:4) v
1319 b <$> const[PV "line "] s
1324 =item B<-stash="somepackage">
1326 With this, "somepackage" will be required, then the stash is
1327 inspected, and each function is rendered.
1331 The following options are pairwise exclusive.
1337 Include the main program in the output, even if subroutines were also
1338 specified. This rendering is normally suppressed when a subroutine
1339 name or reference is given.
1343 This restores the default behavior after you've changed it with '-main'
1344 (it's not normally needed). If no subroutine name/ref is given, main is
1345 rendered, regardless of this flag.
1349 Renderings usually include a banner line identifying the function name
1350 or stringified subref. This suppresses the printing of the banner.
1352 TBC: Remove the stringified coderef; while it provides a 'cookie' for
1353 each function rendered, the cookies used should be 1,2,3.. not a
1354 random hex-address. It also complicates string comparison of two
1359 restores default banner behavior.
1361 =item B<-banneris> => subref
1363 TBC: a hookpoint (and an option to set it) for a user-supplied
1364 function to produce a banner appropriate for users needs. It's not
1365 ideal, because the rendering-state variables, which are a natural
1366 candidate for use in concise.t, are unavailable to the user.
1370 =head2 Option Stickiness
1372 If you invoke Concise more than once in a program, you should know that
1373 the options are 'sticky'. This means that the options you provide in
1374 the first call will be remembered for the 2nd call, unless you
1375 re-specify or change them.
1377 =head1 ABBREVIATIONS
1379 The concise style uses symbols to convey maximum info with minimal
1380 clutter (like hex addresses). With just a little practice, you can
1381 start to see the flowers, not just the branches, in the trees.
1383 =head2 OP class abbreviations
1385 These symbols appear before the op-name, and indicate the
1386 B:: namespace that represents the ops in your Perl code.
1388 0 OP (aka BASEOP) An OP with no children
1389 1 UNOP An OP with one child
1390 + UNOP_AUX A UNOP with auxillary fields
1391 2 BINOP An OP with two children
1392 | LOGOP A control branch OP
1393 @ LISTOP An OP that could have lots of children
1394 / PMOP An OP with a regular expression
1395 $ SVOP An OP with an SV
1396 " PVOP An OP with a string
1397 { LOOP An OP that holds pointers for a loop
1398 ; COP An OP that marks the start of a statement
1399 # PADOP An OP with a GV on the pad
1400 . METHOP An OP with method call info
1402 =head2 OP flags abbreviations
1404 OP flags are either public or private. The public flags alter the
1405 behavior of each opcode in consistent ways, and are represented by 0
1406 or more single characters.
1408 v OPf_WANT_VOID Want nothing (void context)
1409 s OPf_WANT_SCALAR Want single value (scalar context)
1410 l OPf_WANT_LIST Want list of any length (list context)
1412 K OPf_KIDS There is a firstborn child.
1413 P OPf_PARENS This operator was parenthesized.
1414 (Or block needs explicit scope entry.)
1415 R OPf_REF Certified reference.
1416 (Return container, not containee).
1417 M OPf_MOD Will modify (lvalue).
1418 S OPf_STACKED Some arg is arriving on the stack.
1419 * OPf_SPECIAL Do something weird for this op (see op.h)
1421 Private flags, if any are set for an opcode, are displayed after a '/'
1423 8 <@> leave[1 ref] vKP/REFC ->(end)
1424 7 <2> sassign vKS/2 ->8
1426 They're opcode specific, and occur less often than the public ones, so
1427 they're represented by short mnemonics instead of single-chars; see
1428 B::Op_private and F<regen/op_private> for more details.
1430 =head1 FORMATTING SPECIFICATIONS
1432 For each line-style ('concise', 'terse', 'linenoise', etc.) there are
1433 3 format-specs which control how OPs are rendered.
1435 The first is the 'default' format, which is used in both basic and exec
1436 modes to print all opcodes. The 2nd, goto-format, is used in exec
1437 mode when branches are encountered. They're not real opcodes, and are
1438 inserted to look like a closing curly brace. The tree-format is tree
1441 When a line is rendered, the correct format-spec is copied and scanned
1442 for the following items; data is substituted in, and other
1443 manipulations like basic indenting are done, for each opcode rendered.
1445 There are 3 kinds of items that may be populated; special patterns,
1446 #vars, and literal text, which is copied verbatim. (Yes, it's a set
1449 =head2 Special Patterns
1451 These items are the primitives used to perform indenting, and to
1452 select text from amongst alternatives.
1456 =item B<(x(>I<exec_text>B<;>I<basic_text>B<)x)>
1458 Generates I<exec_text> in exec mode, or I<basic_text> in basic mode.
1460 =item B<(*(>I<text>B<)*)>
1462 Generates one copy of I<text> for each indentation level.
1464 =item B<(*(>I<text1>B<;>I<text2>B<)*)>
1466 Generates one fewer copies of I<text1> than the indentation level, followed
1467 by one copy of I<text2> if the indentation level is more than 0.
1469 =item B<(?(>I<text1>B<#>I<var>I<Text2>B<)?)>
1471 If the value of I<var> is true (not empty or zero), generates the
1472 value of I<var> surrounded by I<text1> and I<Text2>, otherwise
1477 Any number of tildes and surrounding whitespace will be collapsed to
1484 These #vars represent opcode properties that you may want as part of
1485 your rendering. The '#' is intended as a private sigil; a #var's
1486 value is interpolated into the style-line, much like "read $this".
1488 These vars take 3 forms:
1494 A property named 'var' is assumed to exist for the opcodes, and is
1495 interpolated into the rendering.
1497 =item B<#>I<var>I<N>
1499 Generates the value of I<var>, left justified to fill I<N> spaces.
1500 Note that this means while you can have properties 'foo' and 'foo2',
1501 you cannot render 'foo2', but you could with 'foo2a'. You would be
1502 wise not to rely on this behavior going forward ;-)
1506 This ucfirst form of #var generates a tag-value form of itself for
1507 display; it converts '#Var' into a 'Var => #var' style, which is then
1508 handled as described above. (Imp-note: #Vars cannot be used for
1509 conditional-fills, because the => #var transform is done after the check
1514 The following variables are 'defined' by B::Concise; when they are
1515 used in a style, their respective values are plugged into the
1516 rendering of each opcode.
1518 Only some of these are used by the standard styles, the others are
1519 provided for you to delve into optree mechanics, should you wish to
1520 add a new style (see L</add_style> below) that uses them. You can
1521 also add new ones using L</add_callback>.
1527 The address of the OP, in hexadecimal.
1531 The OP-specific information of the OP (such as the SV for an SVOP, the
1532 non-local exit pointers for a LOOP, etc.) enclosed in parentheses.
1536 The B-determined class of the OP, in all caps.
1540 A single symbol abbreviating the class of the OP.
1544 The label of the statement or block the OP is the start of, if any.
1548 The name of the OP, or 'ex-foo' if the OP is a null that used to be a foo.
1552 The target of the OP, or nothing for a nulled OP.
1556 The address of the OP's first child, in hexadecimal.
1560 The OP's flags, abbreviated as a series of symbols.
1564 The numeric value of the OP's flags.
1568 The COP's hint flags, rendered with abbreviated names if possible. An empty
1569 string if this is not a COP. Here are the symbols used:
1574 x$ explicit use/no strict refs
1575 x& explicit use/no strict subs
1576 x* explicit use/no strict vars
1596 The numeric value of the COP's hint flags, or an empty string if this is not
1601 The sequence number of the OP, or a hyphen if it doesn't have one.
1605 'NEXT', 'LAST', or 'REDO' if the OP is a target of one of those in exec
1606 mode, or empty otherwise.
1610 The address of the OP's last child, in hexadecimal.
1618 The OP's name, in all caps.
1622 The sequence number of the OP's next OP.
1626 The address of the OP's next OP, in hexadecimal.
1630 A one- or two-character abbreviation for the OP's name.
1634 The OP's private flags, rendered with abbreviated names if possible.
1638 The numeric value of the OP's private flags.
1642 The sequence number of the OP. Note that this is a sequence number
1643 generated by B::Concise.
1647 5.8.x and earlier only. 5.9 and later do not provide this.
1649 The real sequence number of the OP, as a regular number and not adjusted
1650 to be relative to the start of the real program. (This will generally be
1651 a fairly large number because all of B<B::Concise> is compiled before
1656 Whether or not the op has been optimized by the peephole optimizer.
1658 Only available in 5.9 and later.
1662 The address of the OP's next youngest sibling, in hexadecimal.
1666 The address of the OP's SV, if it has an SV, in hexadecimal.
1670 The class of the OP's SV, if it has one, in all caps (e.g., 'IV').
1674 The value of the OP's SV, if it has one, in a short human-readable format.
1678 The numeric value of the OP's targ.
1682 The name of the variable the OP's targ refers to, if any, otherwise the
1683 letter t followed by the OP's targ in decimal.
1685 =item B<#targarglife>
1687 Same as B<#targarg>, but followed by the COP sequence numbers that delimit
1688 the variable's lifetime (or 'end' for a variable in an open scope) for a
1693 The numeric value of the OP's type, in decimal.
1697 =head1 One-Liner Command tips
1701 =item perl -MO=Concise,bar foo.pl
1703 Renders only bar() from foo.pl. To see main, drop the ',bar'. To see
1706 =item perl -MDigest::MD5=md5 -MO=Concise,md5 -e1
1708 Identifies md5 as an XS function. The export is needed so that BC can
1711 =item perl -MPOSIX -MO=Concise,_POSIX_ARG_MAX -e1
1713 Identifies _POSIX_ARG_MAX as a constant sub, optimized to an IV.
1714 Although POSIX isn't entirely consistent across platforms, this is
1715 likely to be present in virtually all of them.
1717 =item perl -MPOSIX -MO=Concise,a -e 'print _POSIX_SAVED_IDS'
1719 This renders a print statement, which includes a call to the function.
1720 It's identical to rendering a file with a use call and that single
1721 statement, except for the filename which appears in the nextstate ops.
1723 =item perl -MPOSIX -MO=Concise,a -e 'sub a{_POSIX_SAVED_IDS}'
1725 This is B<very> similar to previous, only the first two ops differ. This
1726 subroutine rendering is more representative, insofar as a single main
1727 program will have many subs.
1729 =item perl -MB::Concise -e 'B::Concise::compile("-exec","-src", \%B::Concise::)->()'
1731 This renders all functions in the B::Concise package with the source
1732 lines. It eschews the O framework so that the stashref can be passed
1733 directly to B::Concise::compile(). See -stash option for a more
1734 convenient way to render a package.
1738 =head1 Using B::Concise outside of the O framework
1740 The common (and original) usage of B::Concise was for command-line
1741 renderings of simple code, as given in EXAMPLE. But you can also use
1742 B<B::Concise> from your code, and call compile() directly, and
1743 repeatedly. By doing so, you can avoid the compile-time only
1744 operation of O.pm, and even use the debugger to step through
1745 B::Concise::compile() itself.
1747 Once you're doing this, you may alter Concise output by adding new
1748 rendering styles, and by optionally adding callback routines which
1749 populate new variables, if such were referenced from those (just
1752 =head2 Example: Altering Concise Renderings
1754 use B::Concise qw(set_style add_callback);
1755 add_style($yourStyleName => $defaultfmt, $gotofmt, $treefmt);
1758 my ($h, $op, $format, $level, $stylename) = @_;
1759 $h->{variable} = some_func($op);
1761 $walker = B::Concise::compile(@options,@subnames,@subrefs);
1766 B<set_style> accepts 3 arguments, and updates the three format-specs
1767 comprising a line-style (basic-exec, goto, tree). It has one minor
1768 drawback though; it doesn't register the style under a new name. This
1769 can become an issue if you render more than once and switch styles.
1770 Thus you may prefer to use add_style() and/or set_style_standard()
1773 =head2 set_style_standard($name)
1775 This restores one of the standard line-styles: C<terse>, C<concise>,
1776 C<linenoise>, C<debug>, C<env>, into effect. It also accepts style
1777 names previously defined with add_style().
1781 This subroutine accepts a new style name and three style arguments as
1782 above, and creates, registers, and selects the newly named style. It is
1783 an error to re-add a style; call set_style_standard() to switch between
1786 =head2 add_callback ()
1788 If your newly minted styles refer to any new #variables, you'll need
1789 to define a callback subroutine that will populate (or modify) those
1790 variables. They are then available for use in the style you've
1793 The callbacks are called for each opcode visited by Concise, in the
1794 same order as they are added. Each subroutine is passed five
1797 1. A hashref, containing the variable names and values which are
1798 populated into the report-line for the op
1799 2. the op, as a B<B::OP> object
1800 3. a reference to the format string
1801 4. the formatting (indent) level
1802 5. the selected stylename
1804 To define your own variables, simply add them to the hash, or change
1805 existing values if you need to. The level and format are passed in as
1806 references to scalars, but it is unlikely that they will need to be
1807 changed or even used.
1809 =head2 Running B::Concise::compile()
1811 B<compile> accepts options as described above in L</OPTIONS>, and
1812 arguments, which are either coderefs, or subroutine names.
1814 It constructs and returns a $treewalker coderef, which when invoked,
1815 traverses, or walks, and renders the optrees of the given arguments to
1816 STDOUT. You can reuse this, and can change the rendering style used
1817 each time; thereafter the coderef renders in the new style.
1819 B<walk_output> lets you change the print destination from STDOUT to
1820 another open filehandle, or into a string passed as a ref (unless
1821 you've built perl with -Uuseperlio).
1823 my $walker = B::Concise::compile('-terse','aFuncName', \&aSubRef); # 1
1824 walk_output(\my $buf);
1825 $walker->(); # 1 renders -terse
1826 set_style_standard('concise'); # 2
1827 $walker->(); # 2 renders -concise
1828 $walker->(@new); # 3 renders whatever
1829 print "3 different renderings: terse, concise, and @new: $buf\n";
1831 When $walker is called, it traverses the subroutines supplied when it
1832 was created, and renders them using the current style. You can change
1833 the style afterwards in several different ways:
1835 1. call C<compile>, altering style or mode/order
1836 2. call C<set_style_standard>
1837 3. call $walker, passing @new options
1839 Passing new options to the $walker is the easiest way to change
1840 amongst any pre-defined styles (the ones you add are automatically
1841 recognized as options), and is the only way to alter rendering order
1842 without calling compile again. Note however that rendering state is
1843 still shared amongst multiple $walker objects, so they must still be
1844 used in a coordinated manner.
1846 =head2 B::Concise::reset_sequence()
1848 This function (not exported) lets you reset the sequence numbers (note
1849 that they're numbered arbitrarily, their goal being to be human
1850 readable). Its purpose is mostly to support testing, i.e. to compare
1851 the concise output from two identical anonymous subroutines (but
1852 different instances). Without the reset, B::Concise, seeing that
1853 they're separate optrees, generates different sequence numbers in
1858 Errors in rendering (non-existent function-name, non-existent coderef)
1859 are written to the STDOUT, or wherever you've set it via
1862 Errors using the various *style* calls, and bad args to walk_output(),
1863 result in die(). Use an eval if you wish to catch these errors and
1864 continue processing.
1868 Stephen McCamant, E<lt>smcc@CSUA.Berkeley.EDUE<gt>.