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 $VERSION = "0.71";
18 our @ISA = qw(Exporter);
19 our @EXPORT_OK = qw( set_style set_style_standard add_callback
20 concise_subref concise_cv concise_main
21 add_style walk_output compile reset_sequence );
23 ( io => [qw( walk_output compile reset_sequence )],
24 style => [qw( add_style set_style_standard )],
25 cb => [qw( add_callback )],
26 mech => [qw( concise_subref concise_cv concise_main )], );
29 use B qw(class ppname main_start main_root main_cv cstring svref_2object
30 SVf_IOK SVf_NOK SVf_POK SVf_IVisUV SVf_FAKE OPf_KIDS OPf_SPECIAL
35 ["(?(#label =>\n)?)(*( )*)#class (#addr) #name (?([#targ])?) "
36 . "#svclass~(?((#svaddr))?)~#svval~(?(label \"#coplabel\")?)\n",
37 "(*( )*)goto #class (#addr)\n",
40 ["#hyphseq2 (*( (x( ;)x))*)<#classsym> #exname#arg(?([#targarglife])?)"
41 . "~#flags(?(/#private)?)(?(:#hints)?)(x(;~->#next)x)\n"
42 , " (*( )*) goto #seq\n",
43 "(?(<#seq>)?)#exname#arg(?([#targarglife])?)"],
45 ["(x(;(*( )*))x)#noise#arg(?([#targarg])?)(x( ;\n)x)",
47 "(?(#seq)?)#noise#arg(?([#targarg])?)"],
49 ["#class (#addr)\n\top_next\t\t#nextaddr\n\top_sibling\t#sibaddr\n\t"
50 . "op_ppaddr\tPL_ppaddr[OP_#NAME]\n\top_type\t\t#typenum\n" .
51 ($] > 5.009 ? '' : "\top_seq\t\t#seqnum\n")
52 . "\top_flags\t#flagval\n\top_private\t#privval\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 $do_main = 0; # force printing of main routine
78 # another factor: can affect all styles!
79 our @callbacks; # allow external management
81 set_style_standard("concise");
87 ($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 "UNITCHECK") {
325 concise_specials("UNITCHECK", $order,
326 B::unitcheck_av->isa("B::AV") ?
327 B::unitcheck_av->ARRAY : ());
328 } elsif ($objname eq "END") {
329 concise_specials("END", $order,
330 B::end_av->isa("B::AV") ?
331 B::end_av->ARRAY : ());
334 # convert function names to subrefs
337 print $walkHandle "B::Concise::compile($objname)\n"
341 $objname = "main::" . $objname unless $objname =~ /::/;
342 print $walkHandle "$objname:\n";
344 unless (exists &$objname) {
345 print $walkHandle "err: unknown function ($objname)\n";
348 $objref = \&$objname;
350 concise_subref($order, $objref, $objname);
353 if (!@args or $do_main) {
354 print $walkHandle "main program:\n" if $do_main;
355 concise_main($order);
357 return @args; # something
362 my $lastnext; # remembers op-chain, used to insert gotos
364 my %opclass = ('OP' => "0", 'UNOP' => "1", 'BINOP' => "2", 'LOGOP' => "|",
365 'LISTOP' => "@", 'PMOP' => "/", 'SVOP' => "\$", 'GVOP' => "*",
366 'PVOP' => '"', 'LOOP' => "{", 'COP' => ";", 'PADOP' => "#");
368 no warnings 'qw'; # "Possible attempt to put comments..."; use #7
370 qw'# () sc ( @? 1 $* gv *{ m$ m@ m% m? p/ *$ $ $# & a& pt \\ s\\ rf bl
371 ` *? <> ?? ?/ r/ c/ // qr s/ /c y/ = @= C sC Cp sp df un BM po +1 +I
372 -1 -I 1+ I+ 1- I- ** * i* / i/ %$ i% x + i+ - i- . " << >> < i<
373 > i> <= i, >= i. == i= != i! <? i? s< s> s, s. s= s! s? b& b^ b| -0 -i
374 ! ~ a2 si cs rd sr e^ lg sq in %x %o ab le ss ve ix ri sf FL od ch cy
375 uf lf uc lc qm @ [f [ @[ eh vl ky dl ex % ${ @{ uk pk st jn ) )[ a@
376 a% sl +] -] [- [+ so rv GS GW MS MW .. f. .f && || ^^ ?: &= |= -> s{ s}
377 v} ca wa di rs ;; ; ;d }{ { } {} f{ it {l l} rt }l }n }r dm }g }e ^o
378 ^c ^| ^# um bm t~ u~ ~d DB db ^s se ^g ^r {w }w pf pr ^O ^K ^R ^W ^d ^v
379 ^e ^t ^k t. fc ic fl .s .p .b .c .l .a .h g1 s1 g2 s2 ?. l? -R -W -X -r
380 -w -x -e -o -O -z -s -M -A -C -S -c -b -f -d -p -l -u -g -k -t -T -B cd
381 co cr u. cm ut r. l@ s@ r@ mD uD oD rD tD sD wD cD f$ w$ p$ sh e$ k$ g3
382 g4 s4 g5 s5 T@ C@ L@ G@ A@ S@ Hg Hc Hr Hw Mg Mc Ms Mr Sg Sc So rq do {e
383 e} {t t} g6 G6 6e g7 G7 7e g8 G8 8e g9 G9 9e 6s 7s 8s 9s 6E 7E 8E 9E Pn
384 Pu GP SP EP Gn Gg GG SG EG g0 c$ lk t$ ;s n> // /= CO';
386 my $chars = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
388 sub op_flags { # common flags (see BASOP.op_flags in op.h)
391 push @v, "v" if ($x & 3) == 1;
392 push @v, "s" if ($x & 3) == 2;
393 push @v, "l" if ($x & 3) == 3;
394 push @v, "K" if $x & 4;
395 push @v, "P" if $x & 8;
396 push @v, "R" if $x & 16;
397 push @v, "M" if $x & 32;
398 push @v, "S" if $x & 64;
399 push @v, "*" if $x & 128;
405 return "-" . base_n(-$x) if $x < 0;
407 do { $str .= substr($chars, $x % $base, 1) } while $x = int($x / $base);
408 $str = reverse $str if $big_endian;
424 return "-" if not exists $sequence_num{$$op};
425 return base_n($sequence_num{$$op});
429 my($op, $sub, $level) = @_;
431 if ($op->flags & OPf_KIDS) {
432 for (my $kid = $op->first; $$kid; $kid = $kid->sibling) {
433 walk_topdown($kid, $sub, $level + 1);
436 elsif (class($op) eq "PMOP") {
437 my $maybe_root = $op->pmreplroot;
438 if (ref($maybe_root) and $maybe_root->isa("B::OP")) {
439 # It really is the root of the replacement, not something
440 # else stored here for lack of space elsewhere
441 walk_topdown($maybe_root, $sub, $level + 1);
447 my($ar, $level) = @_;
449 if (ref($l) eq "ARRAY") {
450 walklines($l, $level + 1);
458 my($top, $level) = @_;
461 my @todo = ([$top, \@lines]);
462 while (@todo and my($op, $targ) = @{shift @todo}) {
463 for (; $$op; $op = $op->next) {
464 last if $opsseen{$$op}++;
466 my $name = $op->name;
467 if (class($op) eq "LOGOP") {
470 push @todo, [$op->other, $ar];
471 } elsif ($name eq "subst" and $ {$op->pmreplstart}) {
474 push @todo, [$op->pmreplstart, $ar];
475 } elsif ($name =~ /^enter(loop|iter)$/) {
477 $labels{${$op->nextop}} = "NEXT";
478 $labels{${$op->lastop}} = "LAST";
479 $labels{${$op->redoop}} = "REDO";
481 $labels{$op->nextop->seq} = "NEXT";
482 $labels{$op->lastop->seq} = "LAST";
483 $labels{$op->redoop->seq} = "REDO";
488 walklines(\@lines, 0);
491 # The structure of this routine is purposely modeled after op.c's peep()
495 return if class($op) eq "NULL" or exists $sequence_num{$$op};
496 for (; $$op; $op = $op->next) {
497 last if exists $sequence_num{$$op};
498 my $name = $op->name;
499 if ($name =~ /^(null|scalar|lineseq|scope)$/) {
500 next if $oldop and $ {$op->next};
502 $sequence_num{$$op} = $seq_max++;
503 if (class($op) eq "LOGOP") {
504 my $other = $op->other;
505 $other = $other->next while $other->name eq "null";
507 } elsif (class($op) eq "LOOP") {
508 my $redoop = $op->redoop;
509 $redoop = $redoop->next while $redoop->name eq "null";
511 my $nextop = $op->nextop;
512 $nextop = $nextop->next while $nextop->name eq "null";
514 my $lastop = $op->lastop;
515 $lastop = $lastop->next while $lastop->name eq "null";
517 } elsif ($name eq "subst" and $ {$op->pmreplstart}) {
518 my $replstart = $op->pmreplstart;
519 $replstart = $replstart->next while $replstart->name eq "null";
520 sequence($replstart);
527 sub fmt_line { # generate text-line for op.
528 my($hr, $op, $text, $level) = @_;
530 $_->($hr, $op, \$text, \$level, $stylename) for @callbacks;
532 return '' if $hr->{SKIP}; # suppress line if a callback said so
533 return '' if $hr->{goto} and $hr->{goto} eq '-'; # no goto nowhere
535 # spec: (?(text1#varText2)?)
536 $text =~ s/\(\?\(([^\#]*?)\#(\w+)([^\#]*?)\)\?\)/
537 $hr->{$2} ? $1.$hr->{$2}.$3 : ""/eg;
539 # spec: (x(exec_text;basic_text)x)
540 $text =~ s/\(x\((.*?);(.*?)\)x\)/$order eq "exec" ? $1 : $2/egs;
543 $text =~ s/\(\*\(([^;]*?)\)\*\)/$1 x $level/egs;
545 # spec: (*(text1;text2)*)
546 $text =~ s/\(\*\((.*?);(.*?)\)\*\)/$1 x ($level - 1) . $2 x ($level>0)/egs;
548 # convert #Var to tag=>val form: Var\t#var
549 $text =~ s/\#([A-Z][a-z]+)(\d+)?/\t\u$1\t\L#$1$2/gs;
552 $text =~ s/\#([a-zA-Z]+)(\d+)/sprintf("%-$2s", $hr->{$1})/eg;
554 $text =~ s/\#([a-zA-Z]+)/$hr->{$1}/eg; # populate #var's
555 $text =~ s/[ \t]*~+[ \t]*/ /g; # squeeze tildes
557 return "$text\n" if $text ne "";
558 return $text; # suppress empty lines
561 our %priv; # used to display each opcode's BASEOP.op_private values
563 $priv{$_}{128} = "LVINTRO"
564 for ("pos", "substr", "vec", "threadsv", "gvsv", "rv2sv", "rv2hv", "rv2gv",
565 "rv2av", "rv2arylen", "aelem", "helem", "aslice", "hslice", "padsv",
566 "padav", "padhv", "enteriter");
567 $priv{$_}{64} = "REFC" for ("leave", "leavesub", "leavesublv", "leavewrite");
568 $priv{"aassign"}{64} = "COMMON";
569 $priv{"aassign"}{32} = $] < 5.009 ? "PHASH" : "STATE";
570 $priv{"sassign"}{32} = "STATE";
571 $priv{"sassign"}{64} = "BKWARD";
572 $priv{$_}{64} = "RTIME" for ("match", "subst", "substcont", "qr");
573 @{$priv{"trans"}}{1,2,4,8,16,64} = ("<UTF", ">UTF", "IDENT", "SQUASH", "DEL",
575 $priv{"repeat"}{64} = "DOLIST";
576 $priv{"leaveloop"}{64} = "CONT";
577 @{$priv{$_}}{32,64,96} = ("DREFAV", "DREFHV", "DREFSV")
578 for (qw(rv2gv rv2sv padsv aelem helem));
579 $priv{$_}{16} = "STATE" for ("padav", "padhv", "padsv");
580 @{$priv{"entersub"}}{16,32,64} = ("DBG","TARG","NOMOD");
581 @{$priv{$_}}{4,8,128} = ("INARGS","AMPER","NO()") for ("entersub", "rv2cv");
582 $priv{"gv"}{32} = "EARLYCV";
583 $priv{"aelem"}{16} = $priv{"helem"}{16} = "LVDEFER";
584 $priv{$_}{16} = "OURINTR" for ("gvsv", "rv2sv", "rv2av", "rv2hv", "r2gv",
586 $priv{$_}{16} = "TARGMY"
587 for (map(($_,"s$_"),"chop", "chomp"),
588 map(($_,"i_$_"), "postinc", "postdec", "multiply", "divide", "modulo",
589 "add", "subtract", "negate"), "pow", "concat", "stringify",
590 "left_shift", "right_shift", "bit_and", "bit_xor", "bit_or",
591 "complement", "atan2", "sin", "cos", "rand", "exp", "log", "sqrt",
592 "int", "hex", "oct", "abs", "length", "index", "rindex", "sprintf",
593 "ord", "chr", "crypt", "quotemeta", "join", "push", "unshift", "flock",
594 "chdir", "chown", "chroot", "unlink", "chmod", "utime", "rename",
595 "link", "symlink", "mkdir", "rmdir", "wait", "waitpid", "system",
596 "exec", "kill", "getppid", "getpgrp", "setpgrp", "getpriority",
597 "setpriority", "time", "sleep");
598 $priv{$_}{4} = "REVERSED" for ("enteriter", "iter");
599 @{$priv{"const"}}{4,8,16,32,64,128} = ("SHORT","STRICT","ENTERED",'$[',"BARE","WARN");
600 $priv{"flip"}{64} = $priv{"flop"}{64} = "LINENUM";
601 $priv{"list"}{64} = "GUESSED";
602 $priv{"delete"}{64} = "SLICE";
603 $priv{"exists"}{64} = "SUB";
604 @{$priv{"sort"}}{1,2,4,8,16,32,64} = ("NUM", "INT", "REV", "INPLACE","DESC","QSORT","STABLE");
605 $priv{"threadsv"}{64} = "SVREFd";
606 @{$priv{$_}}{16,32,64,128} = ("INBIN","INCR","OUTBIN","OUTCR")
607 for ("open", "backtick");
608 $priv{"exit"}{128} = "VMS";
609 $priv{$_}{2} = "FTACCESS"
610 for ("ftrread", "ftrwrite", "ftrexec", "fteread", "ftewrite", "fteexec");
611 $priv{"entereval"}{2} = "HAS_HH";
613 # Stacked filetests are post 5.8.x
614 $priv{$_}{4} = "FTSTACKED"
615 for ("ftrread", "ftrwrite", "ftrexec", "fteread", "ftewrite", "fteexec",
616 "ftis", "fteowned", "ftrowned", "ftzero", "ftsize", "ftmtime",
617 "ftatime", "ftctime", "ftsock", "ftchr", "ftblk", "ftfile", "ftdir",
618 "ftpipe", "ftlink", "ftsuid", "ftsgid", "ftsvtx", "fttty", "fttext",
620 # Lexical $_ is post 5.8.x
621 $priv{$_}{2} = "GREPLEX"
622 for ("mapwhile", "mapstart", "grepwhile", "grepstart");
625 our %hints; # used to display each COP's op_hints values
627 # strict refs, subs, vars
628 @hints{2,512,1024} = ('$', '&', '*');
629 # integers, locale, bytes, arybase
630 @hints{1,4,8,16,32} = ('i', 'l', 'b', '[');
631 # block scope, localise %^H, $^OPEN
632 @hints{256,131072,262144} = ('{','%','<');
633 # overload new integer, float, binary, string, re
634 @hints{4096,8192,16384,32768,65536} = ('I', 'F', 'B', 'S', 'R');
636 @hints{1048576,2097152} = ('T', 'E');
637 # filetest access, UTF-8, assertions, assertions seen
638 @hints{4194304,8388608,16777216,33554432} = ('X', 'U', 'A', 'a');
643 for my $flag (sort {$b <=> $a} keys %$hash) {
644 if ($hash->{$flag} and $x & $flag and $x >= $flag) {
646 push @s, $hash->{$flag};
650 return join(",", @s);
655 _flags($priv{$name}, $x);
664 my($sv, $hr, $preferpv) = @_;
665 $hr->{svclass} = class($sv);
666 $hr->{svclass} = "UV"
667 if $hr->{svclass} eq "IV" and $sv->FLAGS & SVf_IVisUV;
668 Carp::cluck("bad concise_sv: $sv") unless $sv and $$sv;
669 $hr->{svaddr} = sprintf("%#x", $$sv);
670 if ($hr->{svclass} eq "GV") {
672 my $stash = $gv->STASH->NAME;
673 if ($stash eq "main") {
676 $stash = $stash . "::";
678 $hr->{svval} = "*$stash" . $gv->SAFENAME;
679 return "*$stash" . $gv->SAFENAME;
681 while (class($sv) eq "RV") {
682 $hr->{svval} .= "\\";
685 if (class($sv) eq "SPECIAL") {
686 $hr->{svval} .= ["Null", "sv_undef", "sv_yes", "sv_no"]->[$$sv];
687 } elsif ($preferpv && $sv->FLAGS & SVf_POK) {
688 $hr->{svval} .= cstring($sv->PV);
689 } elsif ($sv->FLAGS & SVf_NOK) {
690 $hr->{svval} .= $sv->NV;
691 } elsif ($sv->FLAGS & SVf_IOK) {
692 $hr->{svval} .= $sv->int_value;
693 } elsif ($sv->FLAGS & SVf_POK) {
694 $hr->{svval} .= cstring($sv->PV);
695 } elsif (class($sv) eq "HV") {
696 $hr->{svval} .= 'HASH';
699 $hr->{svval} = 'undef' unless defined $hr->{svval};
700 my $out = $hr->{svclass};
701 return $out .= " $hr->{svval}" ;
706 my ($op, $level, $format) = @_;
708 $h{exname} = $h{name} = $op->name;
709 $h{NAME} = uc $h{name};
710 $h{class} = class($op);
711 $h{extarg} = $h{targ} = $op->targ;
712 $h{extarg} = "" unless $h{extarg};
713 if ($h{name} eq "null" and $h{targ}) {
714 # targ holds the old type
715 $h{exname} = "ex-" . substr(ppname($h{targ}), 3);
717 } elsif ($op->name =~ /^leave(sub(lv)?|write)?$/) {
718 # targ potentially holds a reference count
719 if ($op->private & 64) {
720 my $refs = "ref" . ($h{targ} != 1 ? "s" : "");
721 $h{targarglife} = $h{targarg} = "$h{targ} $refs";
724 my $padname = (($curcv->PADLIST->ARRAY)[0]->ARRAY)[$h{targ}];
725 if (defined $padname and class($padname) ne "SPECIAL") {
726 $h{targarg} = $padname->PVX;
727 if ($padname->FLAGS & SVf_FAKE) {
729 $h{targarglife} = "$h{targarg}:FAKE";
731 # These changes relate to the jumbo closure fix.
732 # See changes 19939 and 20005
734 $fake .= 'a' if $padname->PARENT_FAKELEX_FLAGS & 1; # PAD_FAKELEX_ANON
735 $fake .= 'm' if $padname->PARENT_FAKELEX_FLAGS & 2; # PAD_FAKELEX_MULTI
736 $fake .= ':' . $padname->PARENT_PAD_INDEX
737 if $curcv->CvFLAGS & CVf_ANON;
738 $h{targarglife} = "$h{targarg}:FAKE:$fake";
742 my $intro = $padname->COP_SEQ_RANGE_LOW - $cop_seq_base;
743 my $finish = int($padname->COP_SEQ_RANGE_HIGH) - $cop_seq_base;
744 $finish = "end" if $finish == 999999999 - $cop_seq_base;
745 $h{targarglife} = "$h{targarg}:$intro,$finish";
748 $h{targarglife} = $h{targarg} = "t" . $h{targ};
752 $h{svclass} = $h{svaddr} = $h{svval} = "";
753 if ($h{class} eq "PMOP") {
754 my $precomp = $op->precomp;
755 if (defined $precomp) {
756 $precomp = cstring($precomp); # Escape literal control sequences
757 $precomp = "/$precomp/";
761 my $pmreplroot = $op->pmreplroot;
763 if (ref($pmreplroot) eq "B::GV") {
764 # with C<@stash_array = split(/pat/, str);>,
765 # *stash_array is stored in /pat/'s pmreplroot.
766 $h{arg} = "($precomp => \@" . $pmreplroot->NAME . ")";
767 } elsif (!ref($pmreplroot) and $pmreplroot) {
768 # same as the last case, except the value is actually a
769 # pad offset for where the GV is kept (this happens under
771 my $gv = (($curcv->PADLIST->ARRAY)[1]->ARRAY)[$pmreplroot];
772 $h{arg} = "($precomp => \@" . $gv->NAME . ")";
773 } elsif ($ {$op->pmreplstart}) {
775 $pmreplstart = "replstart->" . seq($op->pmreplstart);
776 $h{arg} = "(" . join(" ", $precomp, $pmreplstart) . ")";
778 $h{arg} = "($precomp)";
780 } elsif ($h{class} eq "PVOP" and $h{name} ne "trans") {
781 $h{arg} = '("' . $op->pv . '")';
782 $h{svval} = '"' . $op->pv . '"';
783 } elsif ($h{class} eq "COP") {
784 my $label = $op->label;
785 $h{coplabel} = $label;
786 $label = $label ? "$label: " : "";
789 $loc .= ":" . $op->line;
790 my($stash, $cseq) = ($op->stash->NAME, $op->cop_seq - $cop_seq_base);
791 my $arybase = $op->arybase;
792 $arybase = $arybase ? ' $[=' . $arybase : "";
793 $h{arg} = "($label$stash $cseq $loc$arybase)";
794 } elsif ($h{class} eq "LOOP") {
795 $h{arg} = "(next->" . seq($op->nextop) . " last->" . seq($op->lastop)
796 . " redo->" . seq($op->redoop) . ")";
797 } elsif ($h{class} eq "LOGOP") {
799 $h{arg} = "(other->" . seq($op->other) . ")";
801 elsif ($h{class} eq "SVOP" or $h{class} eq "PADOP") {
802 unless ($h{name} eq 'aelemfast' and $op->flags & OPf_SPECIAL) {
803 my $idx = ($h{class} eq "SVOP") ? $op->targ : $op->padix;
804 my $preferpv = $h{name} eq "method_named";
805 if ($h{class} eq "PADOP" or !${$op->sv}) {
806 my $sv = (($curcv->PADLIST->ARRAY)[1]->ARRAY)[$idx];
807 $h{arg} = "[" . concise_sv($sv, \%h, $preferpv) . "]";
808 $h{targarglife} = $h{targarg} = "";
810 $h{arg} = "(" . concise_sv($op->sv, \%h, $preferpv) . ")";
814 $h{seq} = $h{hyphseq} = seq($op);
815 $h{seq} = "" if $h{seq} eq "-";
818 $h{static} = $op->static;
819 $h{label} = $labels{$$op};
821 $h{seqnum} = $op->seq;
822 $h{label} = $labels{$op->seq};
824 $h{next} = $op->next;
825 $h{next} = (class($h{next}) eq "NULL") ? "(end)" : seq($h{next});
826 $h{nextaddr} = sprintf("%#x", $ {$op->next});
827 $h{sibaddr} = sprintf("%#x", $ {$op->sibling});
828 $h{firstaddr} = sprintf("%#x", $ {$op->first}) if $op->can("first");
829 $h{lastaddr} = sprintf("%#x", $ {$op->last}) if $op->can("last");
831 $h{classsym} = $opclass{$h{class}};
832 $h{flagval} = $op->flags;
833 $h{flags} = op_flags($op->flags);
834 $h{privval} = $op->private;
835 $h{private} = private_flags($h{name}, $op->private);
836 if ($op->can("hints")) {
837 $h{hintsval} = $op->hints;
838 $h{hints} = hints_flags($h{hintsval});
840 $h{hintsval} = $h{hints} = '';
842 $h{addr} = sprintf("%#x", $$op);
843 $h{typenum} = $op->type;
844 $h{noise} = $linenoise[$op->type];
846 return fmt_line(\%h, $op, $format, $level);
850 my($op, $level) = @_;
851 if ($order eq "exec" and $lastnext and $$lastnext != $$op) {
852 # insert a 'goto' line
853 my $synth = {"seq" => seq($lastnext), "class" => class($lastnext),
854 "addr" => sprintf("%#x", $$lastnext),
855 "goto" => seq($lastnext), # simplify goto '-' removal
857 print $walkHandle fmt_line($synth, $op, $gotofmt, $level+1);
859 $lastnext = $op->next;
860 print $walkHandle concise_op($op, $level, $format);
863 # B::OP::terse (see Terse.pm) now just calls this
865 my($op, $level) = @_;
867 # This isn't necessarily right, but there's no easy way to get
868 # from an OP to the right CV. This is a limitation of the
869 # ->terse() interface style, and there isn't much to do about
870 # it. In particular, we can die in concise_op if the main pad
871 # isn't long enough, or has the wrong kind of entries, compared to
872 # the pad a sub was compiled with. The fix for that would be to
873 # make a backwards compatible "terse" format that never even
874 # looked at the pad, just like the old B::Terse. I don't think
875 # that's worth the effort, though.
876 $curcv = main_cv unless $curcv;
878 if ($order eq "exec" and $lastnext and $$lastnext != $$op) {
880 my $h = {"seq" => seq($lastnext), "class" => class($lastnext),
881 "addr" => sprintf("%#x", $$lastnext)};
883 fmt_line($h, $op, $style{"terse"}[1], $level+1);
885 $lastnext = $op->next;
887 concise_op($op, $level, $style{"terse"}[0]);
893 my $style = $tree_decorations[$tree_style];
894 my($space, $single, $kids, $kid, $nokid, $last, $lead, $size) = @$style;
895 my $name = concise_op($op, $level, $treefmt);
896 if (not $op->flags & OPf_KIDS) {
900 for (my $kid = $op->first; $$kid; $kid = $kid->sibling) {
901 push @lines, tree($kid, $level+1);
904 for ($i = $#lines; substr($lines[$i], 0, 1) eq " "; $i--) {
905 $lines[$i] = $space . $lines[$i];
908 $lines[$i] = $last . $lines[$i];
910 if (substr($lines[$i], 0, 1) eq " ") {
911 $lines[$i] = $nokid . $lines[$i];
913 $lines[$i] = $kid . $lines[$i];
916 $lines[$i] = $kids . $lines[$i];
918 $lines[0] = $single . $lines[0];
920 return("$name$lead" . shift @lines,
921 map(" " x (length($name)+$size) . $_, @lines));
924 # *** Warning: fragile kludge ahead ***
925 # Because the B::* modules run in the same interpreter as the code
926 # they're compiling, their presence tends to distort the view we have of
927 # the code we're looking at. In particular, perl gives sequence numbers
928 # to COPs. If the program we're looking at were run on its own, this
929 # would start at 1. Because all of B::Concise and all the modules it
930 # uses are compiled first, though, by the time we get to the user's
931 # program the sequence number is already pretty high, which could be
932 # distracting if you're trying to tell OPs apart. Therefore we'd like to
933 # subtract an offset from all the sequence numbers we display, to
934 # restore the simpler view of the world. The trick is to know what that
935 # offset will be, when we're still compiling B::Concise! If we
936 # hardcoded a value, it would have to change every time B::Concise or
937 # other modules we use do. To help a little, what we do here is compile
938 # a little code at the end of the module, and compute the base sequence
939 # number for the user's program as being a small offset later, so all we
940 # have to worry about are changes in the offset.
942 # [For 5.8.x and earlier perl is generating sequence numbers for all ops,
943 # and using them to reference labels]
946 # When you say "perl -MO=Concise -e '$a'", the output should look like:
948 # 4 <@> leave[t1] vKP/REFC ->(end)
950 #^ smallest OP sequence number should be 1
951 # 2 <;> nextstate(main 1 -e:1) v ->3
952 # ^ smallest COP sequence number should be 1
953 # - <1> ex-rv2sv vK/1 ->4
954 # 3 <$> gvsv(*a) s ->4
956 # If the second of the marked numbers there isn't 1, it means you need
957 # to update the corresponding magic number in the next line.
958 # Remember, this needs to stay the last things in the module.
960 # Why is this different for MacOS? Does it matter?
961 my $cop_seq_mnum = $^O eq 'MacOS' ? 12 : 11;
962 $cop_seq_base = svref_2object(eval 'sub{0;}')->START->cop_seq + $cop_seq_mnum;
970 B::Concise - Walk Perl syntax tree, printing concise info about ops
974 perl -MO=Concise[,OPTIONS] foo.pl
976 use B::Concise qw(set_style add_callback);
980 This compiler backend prints the internal OPs of a Perl program's syntax
981 tree in one of several space-efficient text formats suitable for debugging
982 the inner workings of perl or other compiler backends. It can print OPs in
983 the order they appear in the OP tree, in the order they will execute, or
984 in a text approximation to their tree structure, and the format of the
985 information displayed is customizable. Its function is similar to that of
986 perl's B<-Dx> debugging flag or the B<B::Terse> module, but it is more
987 sophisticated and flexible.
991 Here's two outputs (or 'renderings'), using the -exec and -basic
992 (i.e. default) formatting conventions on the same code snippet.
994 % perl -MO=Concise,-exec -e '$a = $b + 42'
996 2 <;> nextstate(main 1 -e:1) v
1002 8 <@> leave[1 ref] vKP/REFC
1004 In this -exec rendering, each opcode is executed in the order shown.
1005 The add opcode, marked with '*', is discussed in more detail.
1007 The 1st column is the op's sequence number, starting at 1, and is
1008 displayed in base 36 by default. Here they're purely linear; the
1009 sequences are very helpful when looking at code with loops and
1012 The symbol between angle brackets indicates the op's type, for
1013 example; <2> is a BINOP, <@> a LISTOP, and <#> is a PADOP, which is
1014 used in threaded perls. (see L</"OP class abbreviations">).
1016 The opname, as in B<'add[t1]'>, may be followed by op-specific
1017 information in parentheses or brackets (ex B<'[t1]'>).
1019 The op-flags (ex B<'sK/2'>) are described in (L</"OP flags
1022 % perl -MO=Concise -e '$a = $b + 42'
1023 8 <@> leave[1 ref] vKP/REFC ->(end)
1025 2 <;> nextstate(main 1 -e:1) v ->3
1026 7 <2> sassign vKS/2 ->8
1027 * 5 <2> add[t1] sK/2 ->6
1028 - <1> ex-rv2sv sK/1 ->4
1029 3 <$> gvsv(*b) s ->4
1030 4 <$> const(IV 42) s ->5
1031 - <1> ex-rv2sv sKRM*/1 ->7
1032 6 <$> gvsv(*a) s ->7
1034 The default rendering is top-down, so they're not in execution order.
1035 This form reflects the way the stack is used to parse and evaluate
1036 expressions; the add operates on the two terms below it in the tree.
1038 Nullops appear as C<ex-opname>, where I<opname> is an op that has been
1039 optimized away by perl. They're displayed with a sequence-number of
1040 '-', because they are not executed (they don't appear in previous
1041 example), they're printed here because they reflect the parse.
1043 The arrow points to the sequence number of the next op; they're not
1044 displayed in -exec mode, for obvious reasons.
1046 Note that because this rendering was done on a non-threaded perl, the
1047 PADOPs in the previous examples are now SVOPs, and some (but not all)
1048 of the square brackets have been replaced by round ones. This is a
1049 subtle feature to provide some visual distinction between renderings
1050 on threaded and un-threaded perls.
1055 Arguments that don't start with a hyphen are taken to be the names of
1056 subroutines to print the OPs of; if no such functions are specified,
1057 the main body of the program (outside any subroutines, and not
1058 including use'd or require'd files) is rendered. Passing C<BEGIN>,
1059 C<UNITCHECK>, C<CHECK>, C<INIT>, or C<END> will cause all of the
1060 corresponding special blocks to be printed.
1062 Options affect how things are rendered (ie printed). They're presented
1063 here by their visual effect, 1st being strongest. They're grouped
1064 according to how they interrelate; within each group the options are
1065 mutually exclusive (unless otherwise stated).
1067 =head2 Options for Opcode Ordering
1069 These options control the 'vertical display' of opcodes. The display
1070 'order' is also called 'mode' elsewhere in this document.
1076 Print OPs in the order they appear in the OP tree (a preorder
1077 traversal, starting at the root). The indentation of each OP shows its
1078 level in the tree, and the '->' at the end of the line indicates the
1079 next opcode in execution order. This mode is the default, so the flag
1080 is included simply for completeness.
1084 Print OPs in the order they would normally execute (for the majority
1085 of constructs this is a postorder traversal of the tree, ending at the
1086 root). In most cases the OP that usually follows a given OP will
1087 appear directly below it; alternate paths are shown by indentation. In
1088 cases like loops when control jumps out of a linear path, a 'goto'
1093 Print OPs in a text approximation of a tree, with the root of the tree
1094 at the left and 'left-to-right' order of children transformed into
1095 'top-to-bottom'. Because this mode grows both to the right and down,
1096 it isn't suitable for large programs (unless you have a very wide
1101 =head2 Options for Line-Style
1103 These options select the line-style (or just style) used to render
1104 each opcode, and dictates what info is actually printed into each line.
1110 Use the author's favorite set of formatting conventions. This is the
1115 Use formatting conventions that emulate the output of B<B::Terse>. The
1116 basic mode is almost indistinguishable from the real B<B::Terse>, and the
1117 exec mode looks very similar, but is in a more logical order and lacks
1118 curly brackets. B<B::Terse> doesn't have a tree mode, so the tree mode
1119 is only vaguely reminiscent of B<B::Terse>.
1123 Use formatting conventions in which the name of each OP, rather than being
1124 written out in full, is represented by a one- or two-character abbreviation.
1125 This is mainly a joke.
1129 Use formatting conventions reminiscent of B<B::Debug>; these aren't
1130 very concise at all.
1134 Use formatting conventions read from the environment variables
1135 C<B_CONCISE_FORMAT>, C<B_CONCISE_GOTO_FORMAT>, and C<B_CONCISE_TREE_FORMAT>.
1139 =head2 Options for tree-specific formatting
1145 Use a tree format in which the minimum amount of space is used for the
1146 lines connecting nodes (one character in most cases). This squeezes out
1147 a few precious columns of screen real estate.
1151 Use a tree format that uses longer edges to separate OP nodes. This format
1152 tends to look better than the compact one, especially in ASCII, and is
1157 Use tree connecting characters drawn from the VT100 line-drawing set.
1158 This looks better if your terminal supports it.
1162 Draw the tree with standard ASCII characters like C<+> and C<|>. These don't
1163 look as clean as the VT100 characters, but they'll work with almost any
1164 terminal (or the horizontal scrolling mode of less(1)) and are suitable
1165 for text documentation or email. This is the default.
1169 These are pairwise exclusive, i.e. compact or loose, vt or ascii.
1171 =head2 Options controlling sequence numbering
1177 Print OP sequence numbers in base I<n>. If I<n> is greater than 10, the
1178 digit for 11 will be 'a', and so on. If I<n> is greater than 36, the digit
1179 for 37 will be 'A', and so on until 62. Values greater than 62 are not
1180 currently supported. The default is 36.
1184 Print sequence numbers with the most significant digit first. This is the
1185 usual convention for Arabic numerals, and the default.
1187 =item B<-littleendian>
1189 Print seqence numbers with the least significant digit first. This is
1190 obviously mutually exclusive with bigendian.
1194 =head2 Other options
1196 These are pairwise exclusive.
1202 Include the main program in the output, even if subroutines were also
1203 specified. This rendering is normally suppressed when a subroutine
1204 name or reference is given.
1208 This restores the default behavior after you've changed it with '-main'
1209 (it's not normally needed). If no subroutine name/ref is given, main is
1210 rendered, regardless of this flag.
1214 Renderings usually include a banner line identifying the function name
1215 or stringified subref. This suppresses the printing of the banner.
1217 TBC: Remove the stringified coderef; while it provides a 'cookie' for
1218 each function rendered, the cookies used should be 1,2,3.. not a
1219 random hex-address. It also complicates string comparison of two
1224 restores default banner behavior.
1226 =item B<-banneris> => subref
1228 TBC: a hookpoint (and an option to set it) for a user-supplied
1229 function to produce a banner appropriate for users needs. It's not
1230 ideal, because the rendering-state variables, which are a natural
1231 candidate for use in concise.t, are unavailable to the user.
1235 =head2 Option Stickiness
1237 If you invoke Concise more than once in a program, you should know that
1238 the options are 'sticky'. This means that the options you provide in
1239 the first call will be remembered for the 2nd call, unless you
1240 re-specify or change them.
1242 =head1 ABBREVIATIONS
1244 The concise style uses symbols to convey maximum info with minimal
1245 clutter (like hex addresses). With just a little practice, you can
1246 start to see the flowers, not just the branches, in the trees.
1248 =head2 OP class abbreviations
1250 These symbols appear before the op-name, and indicate the
1251 B:: namespace that represents the ops in your Perl code.
1253 0 OP (aka BASEOP) An OP with no children
1254 1 UNOP An OP with one child
1255 2 BINOP An OP with two children
1256 | LOGOP A control branch OP
1257 @ LISTOP An OP that could have lots of children
1258 / PMOP An OP with a regular expression
1259 $ SVOP An OP with an SV
1260 " PVOP An OP with a string
1261 { LOOP An OP that holds pointers for a loop
1262 ; COP An OP that marks the start of a statement
1263 # PADOP An OP with a GV on the pad
1265 =head2 OP flags abbreviations
1267 OP flags are either public or private. The public flags alter the
1268 behavior of each opcode in consistent ways, and are represented by 0
1269 or more single characters.
1271 v OPf_WANT_VOID Want nothing (void context)
1272 s OPf_WANT_SCALAR Want single value (scalar context)
1273 l OPf_WANT_LIST Want list of any length (list context)
1275 K OPf_KIDS There is a firstborn child.
1276 P OPf_PARENS This operator was parenthesized.
1277 (Or block needs explicit scope entry.)
1278 R OPf_REF Certified reference.
1279 (Return container, not containee).
1280 M OPf_MOD Will modify (lvalue).
1281 S OPf_STACKED Some arg is arriving on the stack.
1282 * OPf_SPECIAL Do something weird for this op (see op.h)
1284 Private flags, if any are set for an opcode, are displayed after a '/'
1286 8 <@> leave[1 ref] vKP/REFC ->(end)
1287 7 <2> sassign vKS/2 ->8
1289 They're opcode specific, and occur less often than the public ones, so
1290 they're represented by short mnemonics instead of single-chars; see
1291 F<op.h> for gory details, or try this quick 2-liner:
1293 $> perl -MB::Concise -de 1
1294 DB<1> |x \%B::Concise::priv
1296 =head1 FORMATTING SPECIFICATIONS
1298 For each line-style ('concise', 'terse', 'linenoise', etc.) there are
1299 3 format-specs which control how OPs are rendered.
1301 The first is the 'default' format, which is used in both basic and exec
1302 modes to print all opcodes. The 2nd, goto-format, is used in exec
1303 mode when branches are encountered. They're not real opcodes, and are
1304 inserted to look like a closing curly brace. The tree-format is tree
1307 When a line is rendered, the correct format-spec is copied and scanned
1308 for the following items; data is substituted in, and other
1309 manipulations like basic indenting are done, for each opcode rendered.
1311 There are 3 kinds of items that may be populated; special patterns,
1312 #vars, and literal text, which is copied verbatim. (Yes, it's a set
1315 =head2 Special Patterns
1317 These items are the primitives used to perform indenting, and to
1318 select text from amongst alternatives.
1322 =item B<(x(>I<exec_text>B<;>I<basic_text>B<)x)>
1324 Generates I<exec_text> in exec mode, or I<basic_text> in basic mode.
1326 =item B<(*(>I<text>B<)*)>
1328 Generates one copy of I<text> for each indentation level.
1330 =item B<(*(>I<text1>B<;>I<text2>B<)*)>
1332 Generates one fewer copies of I<text1> than the indentation level, followed
1333 by one copy of I<text2> if the indentation level is more than 0.
1335 =item B<(?(>I<text1>B<#>I<var>I<Text2>B<)?)>
1337 If the value of I<var> is true (not empty or zero), generates the
1338 value of I<var> surrounded by I<text1> and I<Text2>, otherwise
1343 Any number of tildes and surrounding whitespace will be collapsed to
1350 These #vars represent opcode properties that you may want as part of
1351 your rendering. The '#' is intended as a private sigil; a #var's
1352 value is interpolated into the style-line, much like "read $this".
1354 These vars take 3 forms:
1360 A property named 'var' is assumed to exist for the opcodes, and is
1361 interpolated into the rendering.
1363 =item B<#>I<var>I<N>
1365 Generates the value of I<var>, left justified to fill I<N> spaces.
1366 Note that this means while you can have properties 'foo' and 'foo2',
1367 you cannot render 'foo2', but you could with 'foo2a'. You would be
1368 wise not to rely on this behavior going forward ;-)
1372 This ucfirst form of #var generates a tag-value form of itself for
1373 display; it converts '#Var' into a 'Var => #var' style, which is then
1374 handled as described above. (Imp-note: #Vars cannot be used for
1375 conditional-fills, because the => #var transform is done after the check
1380 The following variables are 'defined' by B::Concise; when they are
1381 used in a style, their respective values are plugged into the
1382 rendering of each opcode.
1384 Only some of these are used by the standard styles, the others are
1385 provided for you to delve into optree mechanics, should you wish to
1386 add a new style (see L</add_style> below) that uses them. You can
1387 also add new ones using L</add_callback>.
1393 The address of the OP, in hexadecimal.
1397 The OP-specific information of the OP (such as the SV for an SVOP, the
1398 non-local exit pointers for a LOOP, etc.) enclosed in parentheses.
1402 The B-determined class of the OP, in all caps.
1406 A single symbol abbreviating the class of the OP.
1410 The label of the statement or block the OP is the start of, if any.
1414 The name of the OP, or 'ex-foo' if the OP is a null that used to be a foo.
1418 The target of the OP, or nothing for a nulled OP.
1422 The address of the OP's first child, in hexadecimal.
1426 The OP's flags, abbreviated as a series of symbols.
1430 The numeric value of the OP's flags.
1434 The COP's hint flags, rendered with abbreviated names if possible. An empty
1435 string if this is not a COP.
1439 The numeric value of the COP's hint flags, or an empty string if this is not
1444 The sequence number of the OP, or a hyphen if it doesn't have one.
1448 'NEXT', 'LAST', or 'REDO' if the OP is a target of one of those in exec
1449 mode, or empty otherwise.
1453 The address of the OP's last child, in hexadecimal.
1461 The OP's name, in all caps.
1465 The sequence number of the OP's next OP.
1469 The address of the OP's next OP, in hexadecimal.
1473 A one- or two-character abbreviation for the OP's name.
1477 The OP's private flags, rendered with abbreviated names if possible.
1481 The numeric value of the OP's private flags.
1485 The sequence number of the OP. Note that this is a sequence number
1486 generated by B::Concise.
1490 5.8.x and earlier only. 5.9 and later do not provide this.
1492 The real sequence number of the OP, as a regular number and not adjusted
1493 to be relative to the start of the real program. (This will generally be
1494 a fairly large number because all of B<B::Concise> is compiled before
1499 Whether or not the op has been optimised by the peephole optimiser.
1501 Only available in 5.9 and later.
1505 Whether or not the op is statically defined. This flag is used by the
1506 B::C compiler backend and indicates that the op should not be freed.
1508 Only available in 5.9 and later.
1512 The address of the OP's next youngest sibling, in hexadecimal.
1516 The address of the OP's SV, if it has an SV, in hexadecimal.
1520 The class of the OP's SV, if it has one, in all caps (e.g., 'IV').
1524 The value of the OP's SV, if it has one, in a short human-readable format.
1528 The numeric value of the OP's targ.
1532 The name of the variable the OP's targ refers to, if any, otherwise the
1533 letter t followed by the OP's targ in decimal.
1535 =item B<#targarglife>
1537 Same as B<#targarg>, but followed by the COP sequence numbers that delimit
1538 the variable's lifetime (or 'end' for a variable in an open scope) for a
1543 The numeric value of the OP's type, in decimal.
1547 =head1 One-Liner Command tips
1551 =item perl -MO=Concise,bar foo.pl
1553 Renders only bar() from foo.pl. To see main, drop the ',bar'. To see
1556 =item perl -MDigest::MD5=md5 -MO=Concise,md5 -e1
1558 Identifies md5 as an XS function. The export is needed so that BC can
1561 =item perl -MPOSIX -MO=Concise,_POSIX_ARG_MAX -e1
1563 Identifies _POSIX_ARG_MAX as a constant sub, optimized to an IV.
1564 Although POSIX isn't entirely consistent across platforms, this is
1565 likely to be present in virtually all of them.
1567 =item perl -MPOSIX -MO=Concise,a -e 'print _POSIX_SAVED_IDS'
1569 This renders a print statement, which includes a call to the function.
1570 It's identical to rendering a file with a use call and that single
1571 statement, except for the filename which appears in the nextstate ops.
1573 =item perl -MPOSIX -MO=Concise,a -e 'sub a{_POSIX_SAVED_IDS}'
1575 This is B<very> similar to previous, only the first two ops differ. This
1576 subroutine rendering is more representative, insofar as a single main
1577 program will have many subs.
1581 =head1 Using B::Concise outside of the O framework
1583 The common (and original) usage of B::Concise was for command-line
1584 renderings of simple code, as given in EXAMPLE. But you can also use
1585 B<B::Concise> from your code, and call compile() directly, and
1586 repeatedly. By doing so, you can avoid the compile-time only
1587 operation of O.pm, and even use the debugger to step through
1588 B::Concise::compile() itself.
1590 Once you're doing this, you may alter Concise output by adding new
1591 rendering styles, and by optionally adding callback routines which
1592 populate new variables, if such were referenced from those (just
1595 =head2 Example: Altering Concise Renderings
1597 use B::Concise qw(set_style add_callback);
1598 add_style($yourStyleName => $defaultfmt, $gotofmt, $treefmt);
1601 my ($h, $op, $format, $level, $stylename) = @_;
1602 $h->{variable} = some_func($op);
1604 $walker = B::Concise::compile(@options,@subnames,@subrefs);
1609 B<set_style> accepts 3 arguments, and updates the three format-specs
1610 comprising a line-style (basic-exec, goto, tree). It has one minor
1611 drawback though; it doesn't register the style under a new name. This
1612 can become an issue if you render more than once and switch styles.
1613 Thus you may prefer to use add_style() and/or set_style_standard()
1616 =head2 set_style_standard($name)
1618 This restores one of the standard line-styles: C<terse>, C<concise>,
1619 C<linenoise>, C<debug>, C<env>, into effect. It also accepts style
1620 names previously defined with add_style().
1624 This subroutine accepts a new style name and three style arguments as
1625 above, and creates, registers, and selects the newly named style. It is
1626 an error to re-add a style; call set_style_standard() to switch between
1629 =head2 add_callback()
1631 If your newly minted styles refer to any new #variables, you'll need
1632 to define a callback subroutine that will populate (or modify) those
1633 variables. They are then available for use in the style you've
1636 The callbacks are called for each opcode visited by Concise, in the
1637 same order as they are added. Each subroutine is passed five
1640 1. A hashref, containing the variable names and values which are
1641 populated into the report-line for the op
1642 2. the op, as a B<B::OP> object
1643 3. a reference to the format string
1644 4. the formatting (indent) level
1645 5. the selected stylename
1647 To define your own variables, simply add them to the hash, or change
1648 existing values if you need to. The level and format are passed in as
1649 references to scalars, but it is unlikely that they will need to be
1650 changed or even used.
1652 =head2 Running B::Concise::compile()
1654 B<compile> accepts options as described above in L</OPTIONS>, and
1655 arguments, which are either coderefs, or subroutine names.
1657 It constructs and returns a $treewalker coderef, which when invoked,
1658 traverses, or walks, and renders the optrees of the given arguments to
1659 STDOUT. You can reuse this, and can change the rendering style used
1660 each time; thereafter the coderef renders in the new style.
1662 B<walk_output> lets you change the print destination from STDOUT to
1663 another open filehandle, or into a string passed as a ref (unless
1664 you've built perl with -Uuseperlio).
1666 my $walker = B::Concise::compile('-terse','aFuncName', \&aSubRef); # 1
1667 walk_output(\my $buf);
1668 $walker->(); # 1 renders -terse
1669 set_style_standard('concise'); # 2
1670 $walker->(); # 2 renders -concise
1671 $walker->(@new); # 3 renders whatever
1672 print "3 different renderings: terse, concise, and @new: $buf\n";
1674 When $walker is called, it traverses the subroutines supplied when it
1675 was created, and renders them using the current style. You can change
1676 the style afterwards in several different ways:
1678 1. call C<compile>, altering style or mode/order
1679 2. call C<set_style_standard>
1680 3. call $walker, passing @new options
1682 Passing new options to the $walker is the easiest way to change
1683 amongst any pre-defined styles (the ones you add are automatically
1684 recognized as options), and is the only way to alter rendering order
1685 without calling compile again. Note however that rendering state is
1686 still shared amongst multiple $walker objects, so they must still be
1687 used in a coordinated manner.
1689 =head2 B::Concise::reset_sequence()
1691 This function (not exported) lets you reset the sequence numbers (note
1692 that they're numbered arbitrarily, their goal being to be human
1693 readable). Its purpose is mostly to support testing, i.e. to compare
1694 the concise output from two identical anonymous subroutines (but
1695 different instances). Without the reset, B::Concise, seeing that
1696 they're separate optrees, generates different sequence numbers in
1701 Errors in rendering (non-existent function-name, non-existent coderef)
1702 are written to the STDOUT, or wherever you've set it via
1705 Errors using the various *style* calls, and bad args to walk_output(),
1706 result in die(). Use an eval if you wish to catch these errors and
1707 continue processing.
1711 Stephen McCamant, E<lt>smcc@CSUA.Berkeley.EDUE<gt>.