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 $VERSION = "0.68";
18 our @ISA = qw(Exporter);
19 our @EXPORT_OK = qw( set_style set_style_standard add_callback
20 concise_subref concise_cv concise_main
21 add_style walk_output compile reset_sequence );
23 ( io => [qw( walk_output compile reset_sequence )],
24 style => [qw( add_style set_style_standard )],
25 cb => [qw( add_callback )],
26 mech => [qw( concise_subref concise_cv concise_main )], );
29 use B qw(class ppname main_start main_root main_cv cstring svref_2object
30 SVf_IOK SVf_NOK SVf_POK SVf_IVisUV SVf_FAKE OPf_KIDS OPf_SPECIAL
35 ["(?(#label =>\n)?)(*( )*)#class (#addr) #name (?([#targ])?) "
36 . "#svclass~(?((#svaddr))?)~#svval~(?(label \"#coplabel\")?)\n",
37 "(*( )*)goto #class (#addr)\n",
40 ["#hyphseq2 (*( (x( ;)x))*)<#classsym> "
41 . "#exname#arg(?([#targarglife])?)~#flags(?(/#private)?)(x(;~->#next)x)\n"
42 , " (*( )*) goto #seq\n",
43 "(?(<#seq>)?)#exname#arg(?([#targarglife])?)"],
45 ["(x(;(*( )*))x)#noise#arg(?([#targarg])?)(x( ;\n)x)",
47 "(?(#seq)?)#noise#arg(?([#targarg])?)"],
49 ["#class (#addr)\n\top_next\t\t#nextaddr\n\top_sibling\t#sibaddr\n\t"
50 . "op_ppaddr\tPL_ppaddr[OP_#NAME]\n\top_type\t\t#typenum\n" .
51 ($] > 5.009 ? '' : "\top_seq\t\t#seqnum\n")
52 . "\top_flags\t#flagval\n\top_private\t#privval\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 $do_main = 0; # force printing of main routine
78 # another factor: can affect all styles!
79 our @callbacks; # allow external management
81 set_style_standard("concise");
87 ($format, $gotofmt, $treefmt) = @_;
88 #warn "set_style: deprecated, use set_style_standard instead\n"; # someday
89 die "expecting 3 style-format args\n" unless @_ == 3;
93 my ($newstyle,@args) = @_;
94 die "style '$newstyle' already exists, choose a new name\n"
95 if exists $style{$newstyle};
96 die "expecting 3 style-format args\n" unless @args == 3;
97 $style{$newstyle} = [@args];
98 $stylename = $newstyle; # update rendering state
101 sub set_style_standard {
102 ($stylename) = @_; # update rendering state
103 die "err: style '$stylename' unknown\n" unless exists $style{$stylename};
104 set_style(@{$style{$stylename}});
111 # output handle, used with all Concise-output printing
112 our $walkHandle; # public for your convenience
113 BEGIN { $walkHandle = \*STDOUT }
115 sub walk_output { # updates $walkHandle
117 return $walkHandle unless $handle; # allow use as accessor
119 if (ref $handle eq 'SCALAR') {
121 die "no perlio in this build, can't call walk_output (\\\$scalar)\n"
122 unless $Config::Config{useperlio};
123 # in 5.8+, open(FILEHANDLE,MODE,REFERENCE) writes to string
124 open my $tmp, '>', $handle; # but cant re-set existing STDOUT
125 $walkHandle = $tmp; # so use my $tmp as intermediate var
128 my $iotype = ref $handle;
129 die "expecting argument/object that can print\n"
130 unless $iotype eq 'GLOB' or $iotype and $handle->can('print');
131 $walkHandle = $handle;
135 my($order, $coderef, $name) = @_;
136 my $codeobj = svref_2object($coderef);
138 return concise_stashref(@_)
139 unless ref $codeobj eq 'B::CV';
140 concise_cv_obj($order, $codeobj, $name);
143 sub concise_stashref {
145 foreach my $k (sort keys %$h) {
147 my $coderef = *s{CODE} or next;
149 print "FUNC: ", *s, "\n";
150 my $codeobj = svref_2object($coderef);
151 next unless ref $codeobj eq 'B::CV';
152 eval { concise_cv_obj($order, $codeobj) }
153 or warn "err $@ on $codeobj";
157 # This should have been called concise_subref, but it was exported
158 # under this name in versions before 0.56
159 *concise_cv = \&concise_subref;
162 my ($order, $cv, $name) = @_;
163 # name is either a string, or a CODE ref (copy of $cv arg??)
167 if (ref($cv->XSUBANY) =~ /B::(\w+)/) {
168 print $walkHandle "$name is a constant sub, optimized to a $1\n";
172 print $walkHandle "$name is XS code\n";
175 if (class($cv->START) eq "NULL") {
177 if (ref $name eq 'CODE') {
178 print $walkHandle "coderef $name has no START\n";
180 elsif (exists &$name) {
181 print $walkHandle "$name exists in stash, but has no START\n";
184 print $walkHandle "$name not in symbol table\n";
188 sequence($cv->START);
189 if ($order eq "exec") {
190 walk_exec($cv->START);
192 elsif ($order eq "basic") {
193 # walk_topdown($cv->ROOT, sub { $_[0]->concise($_[1]) }, 0);
194 my $root = $cv->ROOT;
195 unless (ref $root eq 'B::NULL') {
196 walk_topdown($root, sub { $_[0]->concise($_[1]) }, 0);
198 print $walkHandle "B::NULL encountered doing ROOT on $cv. avoiding disaster\n";
201 print $walkHandle tree($cv->ROOT, 0);
207 sequence(main_start);
209 if ($order eq "exec") {
210 return if class(main_start) eq "NULL";
211 walk_exec(main_start);
212 } elsif ($order eq "tree") {
213 return if class(main_root) eq "NULL";
214 print $walkHandle tree(main_root, 0);
215 } elsif ($order eq "basic") {
216 return if class(main_root) eq "NULL";
217 walk_topdown(main_root,
218 sub { $_[0]->concise($_[1]) }, 0);
222 sub concise_specials {
223 my($name, $order, @cv_s) = @_;
225 if ($name eq "BEGIN") {
226 splice(@cv_s, 0, 8); # skip 7 BEGIN blocks in this file. NOW 8 ??
227 } elsif ($name eq "CHECK") {
228 pop @cv_s; # skip the CHECK block that calls us
231 print $walkHandle "$name $i:\n";
233 concise_cv_obj($order, $cv, $name);
237 my $start_sym = "\e(0"; # "\cN" sometimes also works
238 my $end_sym = "\e(B"; # "\cO" respectively
240 my @tree_decorations =
241 ([" ", "--", "+-", "|-", "| ", "`-", "-", 1],
242 [" ", "-", "+", "+", "|", "`", "", 0],
243 [" ", map("$start_sym$_$end_sym", "qq", "wq", "tq", "x ", "mq", "q"), 1],
244 [" ", map("$start_sym$_$end_sym", "q", "w", "t", "x", "m"), "", 0],
249 # set rendering state from options and args
252 @options = grep(/^-/, @_);
253 @args = grep(!/^-/, @_);
255 for my $o (@options) {
257 if ($o eq "-basic") {
259 } elsif ($o eq "-exec") {
261 } elsif ($o eq "-tree") {
265 elsif ($o eq "-compact") {
267 } elsif ($o eq "-loose") {
269 } elsif ($o eq "-vt") {
271 } elsif ($o eq "-ascii") {
275 elsif ($o =~ /^-base(\d+)$/) {
277 } elsif ($o eq "-bigendian") {
279 } elsif ($o eq "-littleendian") {
282 elsif ($o eq "-nobanner") {
284 } elsif ($o eq "-banner") {
287 elsif ($o eq "-main") {
289 } elsif ($o eq "-nomain") {
293 elsif (exists $style{substr($o, 1)}) {
294 $stylename = substr($o, 1);
295 set_style_standard($stylename);
297 warn "Option $o unrecognized";
304 my (@args) = compileOpts(@_);
306 my @newargs = compileOpts(@_); # accept new rendering options
307 warn "disregarding non-options: @newargs\n" if @newargs;
309 for my $objname (@args) {
310 next unless $objname; # skip null args to avoid noisy responses
312 if ($objname eq "BEGIN") {
313 concise_specials("BEGIN", $order,
314 B::begin_av->isa("B::AV") ?
315 B::begin_av->ARRAY : ());
316 } elsif ($objname eq "INIT") {
317 concise_specials("INIT", $order,
318 B::init_av->isa("B::AV") ?
319 B::init_av->ARRAY : ());
320 } elsif ($objname eq "CHECK") {
321 concise_specials("CHECK", $order,
322 B::check_av->isa("B::AV") ?
323 B::check_av->ARRAY : ());
324 } elsif ($objname eq "END") {
325 concise_specials("END", $order,
326 B::end_av->isa("B::AV") ?
327 B::end_av->ARRAY : ());
330 # convert function names to subrefs
333 print $walkHandle "B::Concise::compile($objname)\n"
337 $objname = "main::" . $objname unless $objname =~ /::/;
338 print $walkHandle "$objname:\n";
340 unless (exists &$objname) {
341 print $walkHandle "err: unknown function ($objname)\n";
344 $objref = \&$objname;
346 concise_subref($order, $objref, $objname);
349 if (!@args or $do_main) {
350 print $walkHandle "main program:\n" if $do_main;
351 concise_main($order);
353 return @args; # something
358 my $lastnext; # remembers op-chain, used to insert gotos
360 my %opclass = ('OP' => "0", 'UNOP' => "1", 'BINOP' => "2", 'LOGOP' => "|",
361 'LISTOP' => "@", 'PMOP' => "/", 'SVOP' => "\$", 'GVOP' => "*",
362 'PVOP' => '"', 'LOOP' => "{", 'COP' => ";", 'PADOP' => "#");
364 no warnings 'qw'; # "Possible attempt to put comments..."; use #7
366 qw'# () sc ( @? 1 $* gv *{ m$ m@ m% m? p/ *$ $ $# & a& pt \\ s\\ rf bl
367 ` *? <> ?? ?/ r/ c/ // qr s/ /c y/ = @= C sC Cp sp df un BM po +1 +I
368 -1 -I 1+ I+ 1- I- ** * i* / i/ %$ i% x + i+ - i- . " << >> < i<
369 > i> <= i, >= i. == i= != i! <? i? s< s> s, s. s= s! s? b& b^ b| -0 -i
370 ! ~ a2 si cs rd sr e^ lg sq in %x %o ab le ss ve ix ri sf FL od ch cy
371 uf lf uc lc qm @ [f [ @[ eh vl ky dl ex % ${ @{ uk pk st jn ) )[ a@
372 a% sl +] -] [- [+ so rv GS GW MS MW .. f. .f && || ^^ ?: &= |= -> s{ s}
373 v} ca wa di rs ;; ; ;d }{ { } {} f{ it {l l} rt }l }n }r dm }g }e ^o
374 ^c ^| ^# um bm t~ u~ ~d DB db ^s se ^g ^r {w }w pf pr ^O ^K ^R ^W ^d ^v
375 ^e ^t ^k t. fc ic fl .s .p .b .c .l .a .h g1 s1 g2 s2 ?. l? -R -W -X -r
376 -w -x -e -o -O -z -s -M -A -C -S -c -b -f -d -p -l -u -g -k -t -T -B cd
377 co cr u. cm ut r. l@ s@ r@ mD uD oD rD tD sD wD cD f$ w$ p$ sh e$ k$ g3
378 g4 s4 g5 s5 T@ C@ L@ G@ A@ S@ Hg Hc Hr Hw Mg Mc Ms Mr Sg Sc So rq do {e
379 e} {t t} g6 G6 6e g7 G7 7e g8 G8 8e g9 G9 9e 6s 7s 8s 9s 6E 7E 8E 9E Pn
380 Pu GP SP EP Gn Gg GG SG EG g0 c$ lk t$ ;s n> // /= CO';
382 my $chars = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
384 sub op_flags { # common flags (see BASOP.op_flags in op.h)
387 push @v, "v" if ($x & 3) == 1;
388 push @v, "s" if ($x & 3) == 2;
389 push @v, "l" if ($x & 3) == 3;
390 push @v, "K" if $x & 4;
391 push @v, "P" if $x & 8;
392 push @v, "R" if $x & 16;
393 push @v, "M" if $x & 32;
394 push @v, "S" if $x & 64;
395 push @v, "*" if $x & 128;
401 return "-" . base_n(-$x) if $x < 0;
403 do { $str .= substr($chars, $x % $base, 1) } while $x = int($x / $base);
404 $str = reverse $str if $big_endian;
420 return "-" if not exists $sequence_num{$$op};
421 return base_n($sequence_num{$$op});
425 my($op, $sub, $level) = @_;
427 if ($op->flags & OPf_KIDS) {
428 for (my $kid = $op->first; $$kid; $kid = $kid->sibling) {
429 walk_topdown($kid, $sub, $level + 1);
432 elsif (class($op) eq "PMOP") {
433 my $maybe_root = $op->pmreplroot;
434 if (ref($maybe_root) and $maybe_root->isa("B::OP")) {
435 # It really is the root of the replacement, not something
436 # else stored here for lack of space elsewhere
437 walk_topdown($maybe_root, $sub, $level + 1);
443 my($ar, $level) = @_;
445 if (ref($l) eq "ARRAY") {
446 walklines($l, $level + 1);
454 my($top, $level) = @_;
457 my @todo = ([$top, \@lines]);
458 while (@todo and my($op, $targ) = @{shift @todo}) {
459 for (; $$op; $op = $op->next) {
460 last if $opsseen{$$op}++;
462 my $name = $op->name;
463 if (class($op) eq "LOGOP") {
466 push @todo, [$op->other, $ar];
467 } elsif ($name eq "subst" and $ {$op->pmreplstart}) {
470 push @todo, [$op->pmreplstart, $ar];
471 } elsif ($name =~ /^enter(loop|iter)$/) {
473 $labels{${$op->nextop}} = "NEXT";
474 $labels{${$op->lastop}} = "LAST";
475 $labels{${$op->redoop}} = "REDO";
477 $labels{$op->nextop->seq} = "NEXT";
478 $labels{$op->lastop->seq} = "LAST";
479 $labels{$op->redoop->seq} = "REDO";
484 walklines(\@lines, 0);
487 # The structure of this routine is purposely modeled after op.c's peep()
491 return if class($op) eq "NULL" or exists $sequence_num{$$op};
492 for (; $$op; $op = $op->next) {
493 last if exists $sequence_num{$$op};
494 my $name = $op->name;
495 if ($name =~ /^(null|scalar|lineseq|scope)$/) {
496 next if $oldop and $ {$op->next};
498 $sequence_num{$$op} = $seq_max++;
499 if (class($op) eq "LOGOP") {
500 my $other = $op->other;
501 $other = $other->next while $other->name eq "null";
503 } elsif (class($op) eq "LOOP") {
504 my $redoop = $op->redoop;
505 $redoop = $redoop->next while $redoop->name eq "null";
507 my $nextop = $op->nextop;
508 $nextop = $nextop->next while $nextop->name eq "null";
510 my $lastop = $op->lastop;
511 $lastop = $lastop->next while $lastop->name eq "null";
513 } elsif ($name eq "subst" and $ {$op->pmreplstart}) {
514 my $replstart = $op->pmreplstart;
515 $replstart = $replstart->next while $replstart->name eq "null";
516 sequence($replstart);
523 sub fmt_line { # generate text-line for op.
524 my($hr, $op, $text, $level) = @_;
526 $_->($hr, $op, \$text, \$level, $stylename) for @callbacks;
528 return '' if $hr->{SKIP}; # suppress line if a callback said so
529 return '' if $hr->{goto} and $hr->{goto} eq '-'; # no goto nowhere
531 # spec: (?(text1#varText2)?)
532 $text =~ s/\(\?\(([^\#]*?)\#(\w+)([^\#]*?)\)\?\)/
533 $hr->{$2} ? $1.$hr->{$2}.$3 : ""/eg;
535 # spec: (x(exec_text;basic_text)x)
536 $text =~ s/\(x\((.*?);(.*?)\)x\)/$order eq "exec" ? $1 : $2/egs;
539 $text =~ s/\(\*\(([^;]*?)\)\*\)/$1 x $level/egs;
541 # spec: (*(text1;text2)*)
542 $text =~ s/\(\*\((.*?);(.*?)\)\*\)/$1 x ($level - 1) . $2 x ($level>0)/egs;
544 # convert #Var to tag=>val form: Var\t#var
545 $text =~ s/\#([A-Z][a-z]+)(\d+)?/\t\u$1\t\L#$1$2/gs;
548 $text =~ s/\#([a-zA-Z]+)(\d+)/sprintf("%-$2s", $hr->{$1})/eg;
550 $text =~ s/\#([a-zA-Z]+)/$hr->{$1}/eg; # populate #var's
551 $text =~ s/[ \t]*~+[ \t]*/ /g; # squeeze tildes
553 return "$text\n" if $text ne "";
554 return $text; # suppress empty lines
557 our %priv; # used to display each opcode's BASEOP.op_private values
559 $priv{$_}{128} = "LVINTRO"
560 for ("pos", "substr", "vec", "threadsv", "gvsv", "rv2sv", "rv2hv", "rv2gv",
561 "rv2av", "rv2arylen", "aelem", "helem", "aslice", "hslice", "padsv",
562 "padav", "padhv", "enteriter");
563 $priv{$_}{64} = "REFC" for ("leave", "leavesub", "leavesublv", "leavewrite");
564 $priv{"aassign"}{64} = "COMMON";
565 $priv{"aassign"}{32} = "PHASH" if $] < 5.009;
566 $priv{"sassign"}{32} = "STATE";
567 $priv{"sassign"}{64} = "BKWARD";
568 $priv{$_}{64} = "RTIME" for ("match", "subst", "substcont", "qr");
569 @{$priv{"trans"}}{1,2,4,8,16,64} = ("<UTF", ">UTF", "IDENT", "SQUASH", "DEL",
571 $priv{"repeat"}{64} = "DOLIST";
572 $priv{"leaveloop"}{64} = "CONT";
573 @{$priv{$_}}{32,64,96} = ("DREFAV", "DREFHV", "DREFSV")
574 for (qw(rv2gv rv2sv padsv aelem helem));
575 $priv{$_}{16} = "STATE" for ("padav", "padhv", "padsv");
576 @{$priv{"entersub"}}{16,32,64} = ("DBG","TARG","NOMOD");
577 @{$priv{$_}}{4,8,128} = ("INARGS","AMPER","NO()") for ("entersub", "rv2cv");
578 $priv{"gv"}{32} = "EARLYCV";
579 $priv{"aelem"}{16} = $priv{"helem"}{16} = "LVDEFER";
580 $priv{$_}{16} = "OURINTR" for ("gvsv", "rv2sv", "rv2av", "rv2hv", "r2gv",
582 $priv{$_}{16} = "TARGMY"
583 for (map(($_,"s$_"),"chop", "chomp"),
584 map(($_,"i_$_"), "postinc", "postdec", "multiply", "divide", "modulo",
585 "add", "subtract", "negate"), "pow", "concat", "stringify",
586 "left_shift", "right_shift", "bit_and", "bit_xor", "bit_or",
587 "complement", "atan2", "sin", "cos", "rand", "exp", "log", "sqrt",
588 "int", "hex", "oct", "abs", "length", "index", "rindex", "sprintf",
589 "ord", "chr", "crypt", "quotemeta", "join", "push", "unshift", "flock",
590 "chdir", "chown", "chroot", "unlink", "chmod", "utime", "rename",
591 "link", "symlink", "mkdir", "rmdir", "wait", "waitpid", "system",
592 "exec", "kill", "getppid", "getpgrp", "setpgrp", "getpriority",
593 "setpriority", "time", "sleep");
594 $priv{$_}{4} = "REVERSED" for ("enteriter", "iter");
595 @{$priv{"const"}}{4,8,16,32,64,128} = ("SHORT","STRICT","ENTERED",'$[',"BARE","WARN");
596 $priv{"flip"}{64} = $priv{"flop"}{64} = "LINENUM";
597 $priv{"list"}{64} = "GUESSED";
598 $priv{"delete"}{64} = "SLICE";
599 $priv{"exists"}{64} = "SUB";
600 @{$priv{"sort"}}{1,2,4,8,16,32,64} = ("NUM", "INT", "REV", "INPLACE","DESC","QSORT","STABLE");
601 $priv{"threadsv"}{64} = "SVREFd";
602 @{$priv{$_}}{16,32,64,128} = ("INBIN","INCR","OUTBIN","OUTCR")
603 for ("open", "backtick");
604 $priv{"exit"}{128} = "VMS";
605 $priv{$_}{2} = "FTACCESS"
606 for ("ftrread", "ftrwrite", "ftrexec", "fteread", "ftewrite", "fteexec");
607 $priv{"entereval"}{2} = "HAS_HH";
609 # Stacked filetests are post 5.8.x
610 $priv{$_}{4} = "FTSTACKED"
611 for ("ftrread", "ftrwrite", "ftrexec", "fteread", "ftewrite", "fteexec",
612 "ftis", "fteowned", "ftrowned", "ftzero", "ftsize", "ftmtime",
613 "ftatime", "ftctime", "ftsock", "ftchr", "ftblk", "ftfile", "ftdir",
614 "ftpipe", "ftlink", "ftsuid", "ftsgid", "ftsvtx", "fttty", "fttext",
616 # Lexical $_ is post 5.8.x
617 $priv{$_}{2} = "GREPLEX"
618 for ("mapwhile", "mapstart", "grepwhile", "grepstart");
624 for my $flag (128, 96, 64, 32, 16, 8, 4, 2, 1) {
625 if ($priv{$name}{$flag} and $x & $flag and $x >= $flag) {
627 push @s, $priv{$name}{$flag};
631 return join(",", @s);
635 my($sv, $hr, $preferpv) = @_;
636 $hr->{svclass} = class($sv);
637 $hr->{svclass} = "UV"
638 if $hr->{svclass} eq "IV" and $sv->FLAGS & SVf_IVisUV;
639 Carp::cluck("bad concise_sv: $sv") unless $sv and $$sv;
640 $hr->{svaddr} = sprintf("%#x", $$sv);
641 if ($hr->{svclass} eq "GV") {
643 my $stash = $gv->STASH->NAME;
644 if ($stash eq "main") {
647 $stash = $stash . "::";
649 $hr->{svval} = "*$stash" . $gv->SAFENAME;
650 return "*$stash" . $gv->SAFENAME;
652 while (class($sv) eq "RV") {
653 $hr->{svval} .= "\\";
656 if (class($sv) eq "SPECIAL") {
657 $hr->{svval} .= ["Null", "sv_undef", "sv_yes", "sv_no"]->[$$sv];
658 } elsif ($preferpv && $sv->FLAGS & SVf_POK) {
659 $hr->{svval} .= cstring($sv->PV);
660 } elsif ($sv->FLAGS & SVf_NOK) {
661 $hr->{svval} .= $sv->NV;
662 } elsif ($sv->FLAGS & SVf_IOK) {
663 $hr->{svval} .= $sv->int_value;
664 } elsif ($sv->FLAGS & SVf_POK) {
665 $hr->{svval} .= cstring($sv->PV);
666 } elsif (class($sv) eq "HV") {
667 $hr->{svval} .= 'HASH';
670 $hr->{svval} = 'undef' unless defined $hr->{svval};
671 my $out = $hr->{svclass};
672 return $out .= " $hr->{svval}" ;
677 my ($op, $level, $format) = @_;
679 $h{exname} = $h{name} = $op->name;
680 $h{NAME} = uc $h{name};
681 $h{class} = class($op);
682 $h{extarg} = $h{targ} = $op->targ;
683 $h{extarg} = "" unless $h{extarg};
684 if ($h{name} eq "null" and $h{targ}) {
685 # targ holds the old type
686 $h{exname} = "ex-" . substr(ppname($h{targ}), 3);
688 } elsif ($op->name =~ /^leave(sub(lv)?|write)?$/) {
689 # targ potentially holds a reference count
690 if ($op->private & 64) {
691 my $refs = "ref" . ($h{targ} != 1 ? "s" : "");
692 $h{targarglife} = $h{targarg} = "$h{targ} $refs";
695 my $padname = (($curcv->PADLIST->ARRAY)[0]->ARRAY)[$h{targ}];
696 if (defined $padname and class($padname) ne "SPECIAL") {
697 $h{targarg} = $padname->PVX;
698 if ($padname->FLAGS & SVf_FAKE) {
700 $h{targarglife} = "$h{targarg}:FAKE";
702 # These changes relate to the jumbo closure fix.
703 # See changes 19939 and 20005
705 $fake .= 'a' if $padname->IVX & 1; # PAD_FAKELEX_ANON
706 $fake .= 'm' if $padname->IVX & 2; # PAD_FAKELEX_MULTI
707 $fake .= ':' . $padname->NVX if $curcv->CvFLAGS & CVf_ANON;
708 $h{targarglife} = "$h{targarg}:FAKE:$fake";
712 my $intro = $padname->NVX - $cop_seq_base;
713 my $finish = int($padname->IVX) - $cop_seq_base;
714 $finish = "end" if $finish == 999999999 - $cop_seq_base;
715 $h{targarglife} = "$h{targarg}:$intro,$finish";
718 $h{targarglife} = $h{targarg} = "t" . $h{targ};
722 $h{svclass} = $h{svaddr} = $h{svval} = "";
723 if ($h{class} eq "PMOP") {
724 my $precomp = $op->precomp;
725 if (defined $precomp) {
726 $precomp = cstring($precomp); # Escape literal control sequences
727 $precomp = "/$precomp/";
731 my $pmreplroot = $op->pmreplroot;
733 if (ref($pmreplroot) eq "B::GV") {
734 # with C<@stash_array = split(/pat/, str);>,
735 # *stash_array is stored in /pat/'s pmreplroot.
736 $h{arg} = "($precomp => \@" . $pmreplroot->NAME . ")";
737 } elsif (!ref($pmreplroot) and $pmreplroot) {
738 # same as the last case, except the value is actually a
739 # pad offset for where the GV is kept (this happens under
741 my $gv = (($curcv->PADLIST->ARRAY)[1]->ARRAY)[$pmreplroot];
742 $h{arg} = "($precomp => \@" . $gv->NAME . ")";
743 } elsif ($ {$op->pmreplstart}) {
745 $pmreplstart = "replstart->" . seq($op->pmreplstart);
746 $h{arg} = "(" . join(" ", $precomp, $pmreplstart) . ")";
748 $h{arg} = "($precomp)";
750 } elsif ($h{class} eq "PVOP" and $h{name} ne "trans") {
751 $h{arg} = '("' . $op->pv . '")';
752 $h{svval} = '"' . $op->pv . '"';
753 } elsif ($h{class} eq "COP") {
754 my $label = $op->label;
755 $h{coplabel} = $label;
756 $label = $label ? "$label: " : "";
759 $loc .= ":" . $op->line;
760 my($stash, $cseq) = ($op->stash->NAME, $op->cop_seq - $cop_seq_base);
761 my $arybase = $op->arybase;
762 $arybase = $arybase ? ' $[=' . $arybase : "";
763 $h{arg} = "($label$stash $cseq $loc$arybase)";
764 } elsif ($h{class} eq "LOOP") {
765 $h{arg} = "(next->" . seq($op->nextop) . " last->" . seq($op->lastop)
766 . " redo->" . seq($op->redoop) . ")";
767 } elsif ($h{class} eq "LOGOP") {
769 $h{arg} = "(other->" . seq($op->other) . ")";
771 elsif ($h{class} eq "SVOP" or $h{class} eq "PADOP") {
772 unless ($h{name} eq 'aelemfast' and $op->flags & OPf_SPECIAL) {
773 my $idx = ($h{class} eq "SVOP") ? $op->targ : $op->padix;
774 my $preferpv = $h{name} eq "method_named";
775 if ($h{class} eq "PADOP" or !${$op->sv}) {
776 my $sv = (($curcv->PADLIST->ARRAY)[1]->ARRAY)[$idx];
777 $h{arg} = "[" . concise_sv($sv, \%h, $preferpv) . "]";
778 $h{targarglife} = $h{targarg} = "";
780 $h{arg} = "(" . concise_sv($op->sv, \%h, $preferpv) . ")";
784 $h{seq} = $h{hyphseq} = seq($op);
785 $h{seq} = "" if $h{seq} eq "-";
788 $h{static} = $op->static;
789 $h{label} = $labels{$$op};
791 $h{seqnum} = $op->seq;
792 $h{label} = $labels{$op->seq};
794 $h{next} = $op->next;
795 $h{next} = (class($h{next}) eq "NULL") ? "(end)" : seq($h{next});
796 $h{nextaddr} = sprintf("%#x", $ {$op->next});
797 $h{sibaddr} = sprintf("%#x", $ {$op->sibling});
798 $h{firstaddr} = sprintf("%#x", $ {$op->first}) if $op->can("first");
799 $h{lastaddr} = sprintf("%#x", $ {$op->last}) if $op->can("last");
801 $h{classsym} = $opclass{$h{class}};
802 $h{flagval} = $op->flags;
803 $h{flags} = op_flags($op->flags);
804 $h{privval} = $op->private;
805 $h{private} = private_flags($h{name}, $op->private);
806 $h{addr} = sprintf("%#x", $$op);
807 $h{typenum} = $op->type;
808 $h{noise} = $linenoise[$op->type];
810 return fmt_line(\%h, $op, $format, $level);
814 my($op, $level) = @_;
815 if ($order eq "exec" and $lastnext and $$lastnext != $$op) {
816 # insert a 'goto' line
817 my $synth = {"seq" => seq($lastnext), "class" => class($lastnext),
818 "addr" => sprintf("%#x", $$lastnext),
819 "goto" => seq($lastnext), # simplify goto '-' removal
821 print $walkHandle fmt_line($synth, $op, $gotofmt, $level+1);
823 $lastnext = $op->next;
824 print $walkHandle concise_op($op, $level, $format);
827 # B::OP::terse (see Terse.pm) now just calls this
829 my($op, $level) = @_;
831 # This isn't necessarily right, but there's no easy way to get
832 # from an OP to the right CV. This is a limitation of the
833 # ->terse() interface style, and there isn't much to do about
834 # it. In particular, we can die in concise_op if the main pad
835 # isn't long enough, or has the wrong kind of entries, compared to
836 # the pad a sub was compiled with. The fix for that would be to
837 # make a backwards compatible "terse" format that never even
838 # looked at the pad, just like the old B::Terse. I don't think
839 # that's worth the effort, though.
840 $curcv = main_cv unless $curcv;
842 if ($order eq "exec" and $lastnext and $$lastnext != $$op) {
844 my $h = {"seq" => seq($lastnext), "class" => class($lastnext),
845 "addr" => sprintf("%#x", $$lastnext)};
847 fmt_line($h, $op, $style{"terse"}[1], $level+1);
849 $lastnext = $op->next;
851 concise_op($op, $level, $style{"terse"}[0]);
857 my $style = $tree_decorations[$tree_style];
858 my($space, $single, $kids, $kid, $nokid, $last, $lead, $size) = @$style;
859 my $name = concise_op($op, $level, $treefmt);
860 if (not $op->flags & OPf_KIDS) {
864 for (my $kid = $op->first; $$kid; $kid = $kid->sibling) {
865 push @lines, tree($kid, $level+1);
868 for ($i = $#lines; substr($lines[$i], 0, 1) eq " "; $i--) {
869 $lines[$i] = $space . $lines[$i];
872 $lines[$i] = $last . $lines[$i];
874 if (substr($lines[$i], 0, 1) eq " ") {
875 $lines[$i] = $nokid . $lines[$i];
877 $lines[$i] = $kid . $lines[$i];
880 $lines[$i] = $kids . $lines[$i];
882 $lines[0] = $single . $lines[0];
884 return("$name$lead" . shift @lines,
885 map(" " x (length($name)+$size) . $_, @lines));
888 # *** Warning: fragile kludge ahead ***
889 # Because the B::* modules run in the same interpreter as the code
890 # they're compiling, their presence tends to distort the view we have of
891 # the code we're looking at. In particular, perl gives sequence numbers
892 # to COPs. If the program we're looking at were run on its own, this
893 # would start at 1. Because all of B::Concise and all the modules it
894 # uses are compiled first, though, by the time we get to the user's
895 # program the sequence number is already pretty high, which could be
896 # distracting if you're trying to tell OPs apart. Therefore we'd like to
897 # subtract an offset from all the sequence numbers we display, to
898 # restore the simpler view of the world. The trick is to know what that
899 # offset will be, when we're still compiling B::Concise! If we
900 # hardcoded a value, it would have to change every time B::Concise or
901 # other modules we use do. To help a little, what we do here is compile
902 # a little code at the end of the module, and compute the base sequence
903 # number for the user's program as being a small offset later, so all we
904 # have to worry about are changes in the offset.
906 # [For 5.8.x and earlier perl is generating sequence numbers for all ops,
907 # and using them to reference labels]
910 # When you say "perl -MO=Concise -e '$a'", the output should look like:
912 # 4 <@> leave[t1] vKP/REFC ->(end)
914 #^ smallest OP sequence number should be 1
915 # 2 <;> nextstate(main 1 -e:1) v ->3
916 # ^ smallest COP sequence number should be 1
917 # - <1> ex-rv2sv vK/1 ->4
918 # 3 <$> gvsv(*a) s ->4
920 # If the second of the marked numbers there isn't 1, it means you need
921 # to update the corresponding magic number in the next line.
922 # Remember, this needs to stay the last things in the module.
924 # Why is this different for MacOS? Does it matter?
925 my $cop_seq_mnum = $^O eq 'MacOS' ? 12 : 11;
926 $cop_seq_base = svref_2object(eval 'sub{0;}')->START->cop_seq + $cop_seq_mnum;
934 B::Concise - Walk Perl syntax tree, printing concise info about ops
938 perl -MO=Concise[,OPTIONS] foo.pl
940 use B::Concise qw(set_style add_callback);
944 This compiler backend prints the internal OPs of a Perl program's syntax
945 tree in one of several space-efficient text formats suitable for debugging
946 the inner workings of perl or other compiler backends. It can print OPs in
947 the order they appear in the OP tree, in the order they will execute, or
948 in a text approximation to their tree structure, and the format of the
949 information displayed is customizable. Its function is similar to that of
950 perl's B<-Dx> debugging flag or the B<B::Terse> module, but it is more
951 sophisticated and flexible.
955 Here's two outputs (or 'renderings'), using the -exec and -basic
956 (i.e. default) formatting conventions on the same code snippet.
958 % perl -MO=Concise,-exec -e '$a = $b + 42'
960 2 <;> nextstate(main 1 -e:1) v
966 8 <@> leave[1 ref] vKP/REFC
968 In this -exec rendering, each opcode is executed in the order shown.
969 The add opcode, marked with '*', is discussed in more detail.
971 The 1st column is the op's sequence number, starting at 1, and is
972 displayed in base 36 by default. Here they're purely linear; the
973 sequences are very helpful when looking at code with loops and
976 The symbol between angle brackets indicates the op's type, for
977 example; <2> is a BINOP, <@> a LISTOP, and <#> is a PADOP, which is
978 used in threaded perls. (see L</"OP class abbreviations">).
980 The opname, as in B<'add[t1]'>, may be followed by op-specific
981 information in parentheses or brackets (ex B<'[t1]'>).
983 The op-flags (ex B<'sK/2'>) are described in (L</"OP flags
986 % perl -MO=Concise -e '$a = $b + 42'
987 8 <@> leave[1 ref] vKP/REFC ->(end)
989 2 <;> nextstate(main 1 -e:1) v ->3
990 7 <2> sassign vKS/2 ->8
991 * 5 <2> add[t1] sK/2 ->6
992 - <1> ex-rv2sv sK/1 ->4
994 4 <$> const(IV 42) s ->5
995 - <1> ex-rv2sv sKRM*/1 ->7
998 The default rendering is top-down, so they're not in execution order.
999 This form reflects the way the stack is used to parse and evaluate
1000 expressions; the add operates on the two terms below it in the tree.
1002 Nullops appear as C<ex-opname>, where I<opname> is an op that has been
1003 optimized away by perl. They're displayed with a sequence-number of
1004 '-', because they are not executed (they don't appear in previous
1005 example), they're printed here because they reflect the parse.
1007 The arrow points to the sequence number of the next op; they're not
1008 displayed in -exec mode, for obvious reasons.
1010 Note that because this rendering was done on a non-threaded perl, the
1011 PADOPs in the previous examples are now SVOPs, and some (but not all)
1012 of the square brackets have been replaced by round ones. This is a
1013 subtle feature to provide some visual distinction between renderings
1014 on threaded and un-threaded perls.
1019 Arguments that don't start with a hyphen are taken to be the names of
1020 subroutines to print the OPs of; if no such functions are specified,
1021 the main body of the program (outside any subroutines, and not
1022 including use'd or require'd files) is rendered. Passing C<BEGIN>,
1023 C<CHECK>, C<INIT>, or C<END> will cause all of the corresponding
1024 special blocks to be printed.
1026 Options affect how things are rendered (ie printed). They're presented
1027 here by their visual effect, 1st being strongest. They're grouped
1028 according to how they interrelate; within each group the options are
1029 mutually exclusive (unless otherwise stated).
1031 =head2 Options for Opcode Ordering
1033 These options control the 'vertical display' of opcodes. The display
1034 'order' is also called 'mode' elsewhere in this document.
1040 Print OPs in the order they appear in the OP tree (a preorder
1041 traversal, starting at the root). The indentation of each OP shows its
1042 level in the tree, and the '->' at the end of the line indicates the
1043 next opcode in execution order. This mode is the default, so the flag
1044 is included simply for completeness.
1048 Print OPs in the order they would normally execute (for the majority
1049 of constructs this is a postorder traversal of the tree, ending at the
1050 root). In most cases the OP that usually follows a given OP will
1051 appear directly below it; alternate paths are shown by indentation. In
1052 cases like loops when control jumps out of a linear path, a 'goto'
1057 Print OPs in a text approximation of a tree, with the root of the tree
1058 at the left and 'left-to-right' order of children transformed into
1059 'top-to-bottom'. Because this mode grows both to the right and down,
1060 it isn't suitable for large programs (unless you have a very wide
1065 =head2 Options for Line-Style
1067 These options select the line-style (or just style) used to render
1068 each opcode, and dictates what info is actually printed into each line.
1074 Use the author's favorite set of formatting conventions. This is the
1079 Use formatting conventions that emulate the output of B<B::Terse>. The
1080 basic mode is almost indistinguishable from the real B<B::Terse>, and the
1081 exec mode looks very similar, but is in a more logical order and lacks
1082 curly brackets. B<B::Terse> doesn't have a tree mode, so the tree mode
1083 is only vaguely reminiscent of B<B::Terse>.
1087 Use formatting conventions in which the name of each OP, rather than being
1088 written out in full, is represented by a one- or two-character abbreviation.
1089 This is mainly a joke.
1093 Use formatting conventions reminiscent of B<B::Debug>; these aren't
1094 very concise at all.
1098 Use formatting conventions read from the environment variables
1099 C<B_CONCISE_FORMAT>, C<B_CONCISE_GOTO_FORMAT>, and C<B_CONCISE_TREE_FORMAT>.
1103 =head2 Options for tree-specific formatting
1109 Use a tree format in which the minimum amount of space is used for the
1110 lines connecting nodes (one character in most cases). This squeezes out
1111 a few precious columns of screen real estate.
1115 Use a tree format that uses longer edges to separate OP nodes. This format
1116 tends to look better than the compact one, especially in ASCII, and is
1121 Use tree connecting characters drawn from the VT100 line-drawing set.
1122 This looks better if your terminal supports it.
1126 Draw the tree with standard ASCII characters like C<+> and C<|>. These don't
1127 look as clean as the VT100 characters, but they'll work with almost any
1128 terminal (or the horizontal scrolling mode of less(1)) and are suitable
1129 for text documentation or email. This is the default.
1133 These are pairwise exclusive, i.e. compact or loose, vt or ascii.
1135 =head2 Options controlling sequence numbering
1141 Print OP sequence numbers in base I<n>. If I<n> is greater than 10, the
1142 digit for 11 will be 'a', and so on. If I<n> is greater than 36, the digit
1143 for 37 will be 'A', and so on until 62. Values greater than 62 are not
1144 currently supported. The default is 36.
1148 Print sequence numbers with the most significant digit first. This is the
1149 usual convention for Arabic numerals, and the default.
1151 =item B<-littleendian>
1153 Print seqence numbers with the least significant digit first. This is
1154 obviously mutually exclusive with bigendian.
1158 =head2 Other options
1160 These are pairwise exclusive.
1166 Include the main program in the output, even if subroutines were also
1167 specified. This rendering is normally suppressed when a subroutine
1168 name or reference is given.
1172 This restores the default behavior after you've changed it with '-main'
1173 (it's not normally needed). If no subroutine name/ref is given, main is
1174 rendered, regardless of this flag.
1178 Renderings usually include a banner line identifying the function name
1179 or stringified subref. This suppresses the printing of the banner.
1181 TBC: Remove the stringified coderef; while it provides a 'cookie' for
1182 each function rendered, the cookies used should be 1,2,3.. not a
1183 random hex-address. It also complicates string comparison of two
1188 restores default banner behavior.
1190 =item B<-banneris> => subref
1192 TBC: a hookpoint (and an option to set it) for a user-supplied
1193 function to produce a banner appropriate for users needs. It's not
1194 ideal, because the rendering-state variables, which are a natural
1195 candidate for use in concise.t, are unavailable to the user.
1199 =head2 Option Stickiness
1201 If you invoke Concise more than once in a program, you should know that
1202 the options are 'sticky'. This means that the options you provide in
1203 the first call will be remembered for the 2nd call, unless you
1204 re-specify or change them.
1206 =head1 ABBREVIATIONS
1208 The concise style uses symbols to convey maximum info with minimal
1209 clutter (like hex addresses). With just a little practice, you can
1210 start to see the flowers, not just the branches, in the trees.
1212 =head2 OP class abbreviations
1214 These symbols appear before the op-name, and indicate the
1215 B:: namespace that represents the ops in your Perl code.
1217 0 OP (aka BASEOP) An OP with no children
1218 1 UNOP An OP with one child
1219 2 BINOP An OP with two children
1220 | LOGOP A control branch OP
1221 @ LISTOP An OP that could have lots of children
1222 / PMOP An OP with a regular expression
1223 $ SVOP An OP with an SV
1224 " PVOP An OP with a string
1225 { LOOP An OP that holds pointers for a loop
1226 ; COP An OP that marks the start of a statement
1227 # PADOP An OP with a GV on the pad
1229 =head2 OP flags abbreviations
1231 OP flags are either public or private. The public flags alter the
1232 behavior of each opcode in consistent ways, and are represented by 0
1233 or more single characters.
1235 v OPf_WANT_VOID Want nothing (void context)
1236 s OPf_WANT_SCALAR Want single value (scalar context)
1237 l OPf_WANT_LIST Want list of any length (list context)
1239 K OPf_KIDS There is a firstborn child.
1240 P OPf_PARENS This operator was parenthesized.
1241 (Or block needs explicit scope entry.)
1242 R OPf_REF Certified reference.
1243 (Return container, not containee).
1244 M OPf_MOD Will modify (lvalue).
1245 S OPf_STACKED Some arg is arriving on the stack.
1246 * OPf_SPECIAL Do something weird for this op (see op.h)
1248 Private flags, if any are set for an opcode, are displayed after a '/'
1250 8 <@> leave[1 ref] vKP/REFC ->(end)
1251 7 <2> sassign vKS/2 ->8
1253 They're opcode specific, and occur less often than the public ones, so
1254 they're represented by short mnemonics instead of single-chars; see
1255 F<op.h> for gory details, or try this quick 2-liner:
1257 $> perl -MB::Concise -de 1
1258 DB<1> |x \%B::Concise::priv
1260 =head1 FORMATTING SPECIFICATIONS
1262 For each line-style ('concise', 'terse', 'linenoise', etc.) there are
1263 3 format-specs which control how OPs are rendered.
1265 The first is the 'default' format, which is used in both basic and exec
1266 modes to print all opcodes. The 2nd, goto-format, is used in exec
1267 mode when branches are encountered. They're not real opcodes, and are
1268 inserted to look like a closing curly brace. The tree-format is tree
1271 When a line is rendered, the correct format-spec is copied and scanned
1272 for the following items; data is substituted in, and other
1273 manipulations like basic indenting are done, for each opcode rendered.
1275 There are 3 kinds of items that may be populated; special patterns,
1276 #vars, and literal text, which is copied verbatim. (Yes, it's a set
1279 =head2 Special Patterns
1281 These items are the primitives used to perform indenting, and to
1282 select text from amongst alternatives.
1286 =item B<(x(>I<exec_text>B<;>I<basic_text>B<)x)>
1288 Generates I<exec_text> in exec mode, or I<basic_text> in basic mode.
1290 =item B<(*(>I<text>B<)*)>
1292 Generates one copy of I<text> for each indentation level.
1294 =item B<(*(>I<text1>B<;>I<text2>B<)*)>
1296 Generates one fewer copies of I<text1> than the indentation level, followed
1297 by one copy of I<text2> if the indentation level is more than 0.
1299 =item B<(?(>I<text1>B<#>I<var>I<Text2>B<)?)>
1301 If the value of I<var> is true (not empty or zero), generates the
1302 value of I<var> surrounded by I<text1> and I<Text2>, otherwise
1307 Any number of tildes and surrounding whitespace will be collapsed to
1314 These #vars represent opcode properties that you may want as part of
1315 your rendering. The '#' is intended as a private sigil; a #var's
1316 value is interpolated into the style-line, much like "read $this".
1318 These vars take 3 forms:
1324 A property named 'var' is assumed to exist for the opcodes, and is
1325 interpolated into the rendering.
1327 =item B<#>I<var>I<N>
1329 Generates the value of I<var>, left justified to fill I<N> spaces.
1330 Note that this means while you can have properties 'foo' and 'foo2',
1331 you cannot render 'foo2', but you could with 'foo2a'. You would be
1332 wise not to rely on this behavior going forward ;-)
1336 This ucfirst form of #var generates a tag-value form of itself for
1337 display; it converts '#Var' into a 'Var => #var' style, which is then
1338 handled as described above. (Imp-note: #Vars cannot be used for
1339 conditional-fills, because the => #var transform is done after the check
1344 The following variables are 'defined' by B::Concise; when they are
1345 used in a style, their respective values are plugged into the
1346 rendering of each opcode.
1348 Only some of these are used by the standard styles, the others are
1349 provided for you to delve into optree mechanics, should you wish to
1350 add a new style (see L</add_style> below) that uses them. You can
1351 also add new ones using L</add_callback>.
1357 The address of the OP, in hexadecimal.
1361 The OP-specific information of the OP (such as the SV for an SVOP, the
1362 non-local exit pointers for a LOOP, etc.) enclosed in parentheses.
1366 The B-determined class of the OP, in all caps.
1370 A single symbol abbreviating the class of the OP.
1374 The label of the statement or block the OP is the start of, if any.
1378 The name of the OP, or 'ex-foo' if the OP is a null that used to be a foo.
1382 The target of the OP, or nothing for a nulled OP.
1386 The address of the OP's first child, in hexadecimal.
1390 The OP's flags, abbreviated as a series of symbols.
1394 The numeric value of the OP's flags.
1398 The sequence number of the OP, or a hyphen if it doesn't have one.
1402 'NEXT', 'LAST', or 'REDO' if the OP is a target of one of those in exec
1403 mode, or empty otherwise.
1407 The address of the OP's last child, in hexadecimal.
1415 The OP's name, in all caps.
1419 The sequence number of the OP's next OP.
1423 The address of the OP's next OP, in hexadecimal.
1427 A one- or two-character abbreviation for the OP's name.
1431 The OP's private flags, rendered with abbreviated names if possible.
1435 The numeric value of the OP's private flags.
1439 The sequence number of the OP. Note that this is a sequence number
1440 generated by B::Concise.
1444 5.8.x and earlier only. 5.9 and later do not provide this.
1446 The real sequence number of the OP, as a regular number and not adjusted
1447 to be relative to the start of the real program. (This will generally be
1448 a fairly large number because all of B<B::Concise> is compiled before
1453 Whether or not the op has been optimised by the peephole optimiser.
1455 Only available in 5.9 and later.
1459 Whether or not the op is statically defined. This flag is used by the
1460 B::C compiler backend and indicates that the op should not be freed.
1462 Only available in 5.9 and later.
1466 The address of the OP's next youngest sibling, in hexadecimal.
1470 The address of the OP's SV, if it has an SV, in hexadecimal.
1474 The class of the OP's SV, if it has one, in all caps (e.g., 'IV').
1478 The value of the OP's SV, if it has one, in a short human-readable format.
1482 The numeric value of the OP's targ.
1486 The name of the variable the OP's targ refers to, if any, otherwise the
1487 letter t followed by the OP's targ in decimal.
1489 =item B<#targarglife>
1491 Same as B<#targarg>, but followed by the COP sequence numbers that delimit
1492 the variable's lifetime (or 'end' for a variable in an open scope) for a
1497 The numeric value of the OP's type, in decimal.
1501 =head1 One-Liner Command tips
1505 =item perl -MO=Concise,bar foo.pl
1507 Renders only bar() from foo.pl. To see main, drop the ',bar'. To see
1510 =item perl -MDigest::MD5=md5 -MO=Concise,md5 -e1
1512 Identifies md5 as an XS function. The export is needed so that BC can
1515 =item perl -MPOSIX -MO=Concise,_POSIX_ARG_MAX -e1
1517 Identifies _POSIX_ARG_MAX as a constant sub, optimized to an IV.
1518 Although POSIX isn't entirely consistent across platforms, this is
1519 likely to be present in virtually all of them.
1521 =item perl -MPOSIX -MO=Concise,a -e 'print _POSIX_SAVED_IDS'
1523 This renders a print statement, which includes a call to the function.
1524 It's identical to rendering a file with a use call and that single
1525 statement, except for the filename which appears in the nextstate ops.
1527 =item perl -MPOSIX -MO=Concise,a -e 'sub a{_POSIX_SAVED_IDS}'
1529 This is B<very> similar to previous, only the first two ops differ. This
1530 subroutine rendering is more representative, insofar as a single main
1531 program will have many subs.
1535 =head1 Using B::Concise outside of the O framework
1537 The common (and original) usage of B::Concise was for command-line
1538 renderings of simple code, as given in EXAMPLE. But you can also use
1539 B<B::Concise> from your code, and call compile() directly, and
1540 repeatedly. By doing so, you can avoid the compile-time only
1541 operation of O.pm, and even use the debugger to step through
1542 B::Concise::compile() itself.
1544 Once you're doing this, you may alter Concise output by adding new
1545 rendering styles, and by optionally adding callback routines which
1546 populate new variables, if such were referenced from those (just
1549 =head2 Example: Altering Concise Renderings
1551 use B::Concise qw(set_style add_callback);
1552 add_style($yourStyleName => $defaultfmt, $gotofmt, $treefmt);
1555 my ($h, $op, $format, $level, $stylename) = @_;
1556 $h->{variable} = some_func($op);
1558 $walker = B::Concise::compile(@options,@subnames,@subrefs);
1563 B<set_style> accepts 3 arguments, and updates the three format-specs
1564 comprising a line-style (basic-exec, goto, tree). It has one minor
1565 drawback though; it doesn't register the style under a new name. This
1566 can become an issue if you render more than once and switch styles.
1567 Thus you may prefer to use add_style() and/or set_style_standard()
1570 =head2 set_style_standard($name)
1572 This restores one of the standard line-styles: C<terse>, C<concise>,
1573 C<linenoise>, C<debug>, C<env>, into effect. It also accepts style
1574 names previously defined with add_style().
1578 This subroutine accepts a new style name and three style arguments as
1579 above, and creates, registers, and selects the newly named style. It is
1580 an error to re-add a style; call set_style_standard() to switch between
1583 =head2 add_callback()
1585 If your newly minted styles refer to any new #variables, you'll need
1586 to define a callback subroutine that will populate (or modify) those
1587 variables. They are then available for use in the style you've
1590 The callbacks are called for each opcode visited by Concise, in the
1591 same order as they are added. Each subroutine is passed five
1594 1. A hashref, containing the variable names and values which are
1595 populated into the report-line for the op
1596 2. the op, as a B<B::OP> object
1597 3. a reference to the format string
1598 4. the formatting (indent) level
1599 5. the selected stylename
1601 To define your own variables, simply add them to the hash, or change
1602 existing values if you need to. The level and format are passed in as
1603 references to scalars, but it is unlikely that they will need to be
1604 changed or even used.
1606 =head2 Running B::Concise::compile()
1608 B<compile> accepts options as described above in L</OPTIONS>, and
1609 arguments, which are either coderefs, or subroutine names.
1611 It constructs and returns a $treewalker coderef, which when invoked,
1612 traverses, or walks, and renders the optrees of the given arguments to
1613 STDOUT. You can reuse this, and can change the rendering style used
1614 each time; thereafter the coderef renders in the new style.
1616 B<walk_output> lets you change the print destination from STDOUT to
1617 another open filehandle, or into a string passed as a ref (unless
1618 you've built perl with -Uuseperlio).
1620 my $walker = B::Concise::compile('-terse','aFuncName', \&aSubRef); # 1
1621 walk_output(\my $buf);
1622 $walker->(); # 1 renders -terse
1623 set_style_standard('concise'); # 2
1624 $walker->(); # 2 renders -concise
1625 $walker->(@new); # 3 renders whatever
1626 print "3 different renderings: terse, concise, and @new: $buf\n";
1628 When $walker is called, it traverses the subroutines supplied when it
1629 was created, and renders them using the current style. You can change
1630 the style afterwards in several different ways:
1632 1. call C<compile>, altering style or mode/order
1633 2. call C<set_style_standard>
1634 3. call $walker, passing @new options
1636 Passing new options to the $walker is the easiest way to change
1637 amongst any pre-defined styles (the ones you add are automatically
1638 recognized as options), and is the only way to alter rendering order
1639 without calling compile again. Note however that rendering state is
1640 still shared amongst multiple $walker objects, so they must still be
1641 used in a coordinated manner.
1643 =head2 B::Concise::reset_sequence()
1645 This function (not exported) lets you reset the sequence numbers (note
1646 that they're numbered arbitrarily, their goal being to be human
1647 readable). Its purpose is mostly to support testing, i.e. to compare
1648 the concise output from two identical anonymous subroutines (but
1649 different instances). Without the reset, B::Concise, seeing that
1650 they're separate optrees, generates different sequence numbers in
1655 Errors in rendering (non-existent function-name, non-existent coderef)
1656 are written to the STDOUT, or wherever you've set it via
1659 Errors using the various *style* calls, and bad args to walk_output(),
1660 result in die(). Use an eval if you wish to catch these errors and
1661 continue processing.
1665 Stephen McCamant, E<lt>smcc@CSUA.Berkeley.EDUE<gt>.