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 $VERSION = "0.73";
18 our @ISA = qw(Exporter);
19 our @EXPORT_OK = qw( set_style set_style_standard add_callback
20 concise_subref concise_cv concise_main
21 add_style walk_output compile reset_sequence );
23 ( io => [qw( walk_output compile reset_sequence )],
24 style => [qw( add_style set_style_standard )],
25 cb => [qw( add_callback )],
26 mech => [qw( concise_subref concise_cv concise_main )], );
29 use B qw(class ppname main_start main_root main_cv cstring svref_2object
30 SVf_IOK SVf_NOK SVf_POK SVf_IVisUV SVf_FAKE OPf_KIDS OPf_SPECIAL
31 CVf_ANON PAD_FAKELEX_ANON PAD_FAKELEX_MULTI);
35 ["(?(#label =>\n)?)(*( )*)#class (#addr) #name (?([#targ])?) "
36 . "#svclass~(?((#svaddr))?)~#svval~(?(label \"#coplabel\")?)\n",
37 "(*( )*)goto #class (#addr)\n",
40 ["#hyphseq2 (*( (x( ;)x))*)<#classsym> #exname#arg(?([#targarglife])?)"
41 . "~#flags(?(/#private)?)(?(:#hints)?)(x(;~->#next)x)\n"
42 , " (*( )*) goto #seq\n",
43 "(?(<#seq>)?)#exname#arg(?([#targarglife])?)"],
45 ["(x(;(*( )*))x)#noise#arg(?([#targarg])?)(x( ;\n)x)",
47 "(?(#seq)?)#noise#arg(?([#targarg])?)"],
49 ["#class (#addr)\n\top_next\t\t#nextaddr\n\top_sibling\t#sibaddr\n\t"
50 . "op_ppaddr\tPL_ppaddr[OP_#NAME]\n\top_type\t\t#typenum\n" .
51 ($] > 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
77 my $show_src; # show source code
79 # another factor: can affect all styles!
80 our @callbacks; # allow external management
82 set_style_standard("concise");
88 ($format, $gotofmt, $treefmt) = @_;
89 #warn "set_style: deprecated, use set_style_standard instead\n"; # someday
90 die "expecting 3 style-format args\n" unless @_ == 3;
94 my ($newstyle,@args) = @_;
95 die "style '$newstyle' already exists, choose a new name\n"
96 if exists $style{$newstyle};
97 die "expecting 3 style-format args\n" unless @args == 3;
98 $style{$newstyle} = [@args];
99 $stylename = $newstyle; # update rendering state
102 sub set_style_standard {
103 ($stylename) = @_; # update rendering state
104 die "err: style '$stylename' unknown\n" unless exists $style{$stylename};
105 set_style(@{$style{$stylename}});
112 # output handle, used with all Concise-output printing
113 our $walkHandle; # public for your convenience
114 BEGIN { $walkHandle = \*STDOUT }
116 sub walk_output { # updates $walkHandle
118 return $walkHandle unless $handle; # allow use as accessor
120 if (ref $handle eq 'SCALAR') {
122 die "no perlio in this build, can't call walk_output (\\\$scalar)\n"
123 unless $Config::Config{useperlio};
124 # in 5.8+, open(FILEHANDLE,MODE,REFERENCE) writes to string
125 open my $tmp, '>', $handle; # but cant re-set existing STDOUT
126 $walkHandle = $tmp; # so use my $tmp as intermediate var
129 my $iotype = ref $handle;
130 die "expecting argument/object that can print\n"
131 unless $iotype eq 'GLOB' or $iotype and $handle->can('print');
132 $walkHandle = $handle;
136 my($order, $coderef, $name) = @_;
137 my $codeobj = svref_2object($coderef);
139 return concise_stashref(@_)
140 unless ref $codeobj eq 'B::CV';
141 concise_cv_obj($order, $codeobj, $name);
144 sub concise_stashref {
146 foreach my $k (sort keys %$h) {
148 my $coderef = *s{CODE} or next;
150 print "FUNC: ", *s, "\n";
151 my $codeobj = svref_2object($coderef);
152 next unless ref $codeobj eq 'B::CV';
153 eval { concise_cv_obj($order, $codeobj) }
154 or warn "err $@ on $codeobj";
158 # This should have been called concise_subref, but it was exported
159 # under this name in versions before 0.56
160 *concise_cv = \&concise_subref;
163 my ($order, $cv, $name) = @_;
164 # name is either a string, or a CODE ref (copy of $cv arg??)
168 if (ref($cv->XSUBANY) =~ /B::(\w+)/) {
169 print $walkHandle "$name is a constant sub, optimized to a $1\n";
173 print $walkHandle "$name is XS code\n";
176 if (class($cv->START) eq "NULL") {
178 if (ref $name eq 'CODE') {
179 print $walkHandle "coderef $name has no START\n";
181 elsif (exists &$name) {
182 print $walkHandle "$name exists in stash, but has no START\n";
185 print $walkHandle "$name not in symbol table\n";
189 sequence($cv->START);
190 if ($order eq "exec") {
191 walk_exec($cv->START);
193 elsif ($order eq "basic") {
194 # walk_topdown($cv->ROOT, sub { $_[0]->concise($_[1]) }, 0);
195 my $root = $cv->ROOT;
196 unless (ref $root eq 'B::NULL') {
197 walk_topdown($root, sub { $_[0]->concise($_[1]) }, 0);
199 print $walkHandle "B::NULL encountered doing ROOT on $cv. avoiding disaster\n";
202 print $walkHandle tree($cv->ROOT, 0);
208 sequence(main_start);
210 if ($order eq "exec") {
211 return if class(main_start) eq "NULL";
212 walk_exec(main_start);
213 } elsif ($order eq "tree") {
214 return if class(main_root) eq "NULL";
215 print $walkHandle tree(main_root, 0);
216 } elsif ($order eq "basic") {
217 return if class(main_root) eq "NULL";
218 walk_topdown(main_root,
219 sub { $_[0]->concise($_[1]) }, 0);
223 sub concise_specials {
224 my($name, $order, @cv_s) = @_;
226 if ($name eq "BEGIN") {
227 splice(@cv_s, 0, 8); # skip 7 BEGIN blocks in this file. NOW 8 ??
228 } elsif ($name eq "CHECK") {
229 pop @cv_s; # skip the CHECK block that calls us
232 print $walkHandle "$name $i:\n";
234 concise_cv_obj($order, $cv, $name);
238 my $start_sym = "\e(0"; # "\cN" sometimes also works
239 my $end_sym = "\e(B"; # "\cO" respectively
241 my @tree_decorations =
242 ([" ", "--", "+-", "|-", "| ", "`-", "-", 1],
243 [" ", "-", "+", "+", "|", "`", "", 0],
244 [" ", map("$start_sym$_$end_sym", "qq", "wq", "tq", "x ", "mq", "q"), 1],
245 [" ", 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") {
291 } elsif ($o eq "-src") {
296 elsif (exists $style{substr($o, 1)}) {
297 $stylename = substr($o, 1);
298 set_style_standard($stylename);
300 warn "Option $o unrecognized";
307 my (@args) = compileOpts(@_);
309 my @newargs = compileOpts(@_); # accept new rendering options
310 warn "disregarding non-options: @newargs\n" if @newargs;
312 for my $objname (@args) {
313 next unless $objname; # skip null args to avoid noisy responses
315 if ($objname eq "BEGIN") {
316 concise_specials("BEGIN", $order,
317 B::begin_av->isa("B::AV") ?
318 B::begin_av->ARRAY : ());
319 } elsif ($objname eq "INIT") {
320 concise_specials("INIT", $order,
321 B::init_av->isa("B::AV") ?
322 B::init_av->ARRAY : ());
323 } elsif ($objname eq "CHECK") {
324 concise_specials("CHECK", $order,
325 B::check_av->isa("B::AV") ?
326 B::check_av->ARRAY : ());
327 } elsif ($objname eq "UNITCHECK") {
328 concise_specials("UNITCHECK", $order,
329 B::unitcheck_av->isa("B::AV") ?
330 B::unitcheck_av->ARRAY : ());
331 } elsif ($objname eq "END") {
332 concise_specials("END", $order,
333 B::end_av->isa("B::AV") ?
334 B::end_av->ARRAY : ());
337 # convert function names to subrefs
340 print $walkHandle "B::Concise::compile($objname)\n"
344 $objname = "main::" . $objname unless $objname =~ /::/;
345 print $walkHandle "$objname:\n";
347 unless (exists &$objname) {
348 print $walkHandle "err: unknown function ($objname)\n";
351 $objref = \&$objname;
353 concise_subref($order, $objref, $objname);
356 if (!@args or $do_main) {
357 print $walkHandle "main program:\n" if $do_main;
358 concise_main($order);
360 return @args; # something
365 my $lastnext; # remembers op-chain, used to insert gotos
367 my %opclass = ('OP' => "0", 'UNOP' => "1", 'BINOP' => "2", 'LOGOP' => "|",
368 'LISTOP' => "@", 'PMOP' => "/", 'SVOP' => "\$", 'GVOP' => "*",
369 'PVOP' => '"', 'LOOP' => "{", 'COP' => ";", 'PADOP' => "#");
371 no warnings 'qw'; # "Possible attempt to put comments..."; use #7
373 qw'# () sc ( @? 1 $* gv *{ m$ m@ m% m? p/ *$ $ $# & a& pt \\ s\\ rf bl
374 ` *? <> ?? ?/ r/ c/ // qr s/ /c y/ = @= C sC Cp sp df un BM po +1 +I
375 -1 -I 1+ I+ 1- I- ** * i* / i/ %$ i% x + i+ - i- . " << >> < i<
376 > i> <= i, >= i. == i= != i! <? i? s< s> s, s. s= s! s? b& b^ b| -0 -i
377 ! ~ a2 si cs rd sr e^ lg sq in %x %o ab le ss ve ix ri sf FL od ch cy
378 uf lf uc lc qm @ [f [ @[ eh vl ky dl ex % ${ @{ uk pk st jn ) )[ a@
379 a% sl +] -] [- [+ so rv GS GW MS MW .. f. .f && || ^^ ?: &= |= -> s{ s}
380 v} ca wa di rs ;; ; ;d }{ { } {} f{ it {l l} rt }l }n }r dm }g }e ^o
381 ^c ^| ^# um bm t~ u~ ~d DB db ^s se ^g ^r {w }w pf pr ^O ^K ^R ^W ^d ^v
382 ^e ^t ^k t. fc ic fl .s .p .b .c .l .a .h g1 s1 g2 s2 ?. l? -R -W -X -r
383 -w -x -e -o -O -z -s -M -A -C -S -c -b -f -d -p -l -u -g -k -t -T -B cd
384 co cr u. cm ut r. l@ s@ r@ mD uD oD rD tD sD wD cD f$ w$ p$ sh e$ k$ g3
385 g4 s4 g5 s5 T@ C@ L@ G@ A@ S@ Hg Hc Hr Hw Mg Mc Ms Mr Sg Sc So rq do {e
386 e} {t t} g6 G6 6e g7 G7 7e g8 G8 8e g9 G9 9e 6s 7s 8s 9s 6E 7E 8E 9E Pn
387 Pu GP SP EP Gn Gg GG SG EG g0 c$ lk t$ ;s n> // /= CO';
389 my $chars = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ";
391 sub op_flags { # common flags (see BASOP.op_flags in op.h)
394 push @v, "v" if ($x & 3) == 1;
395 push @v, "s" if ($x & 3) == 2;
396 push @v, "l" if ($x & 3) == 3;
397 push @v, "K" if $x & 4;
398 push @v, "P" if $x & 8;
399 push @v, "R" if $x & 16;
400 push @v, "M" if $x & 32;
401 push @v, "S" if $x & 64;
402 push @v, "*" if $x & 128;
408 return "-" . base_n(-$x) if $x < 0;
410 do { $str .= substr($chars, $x % $base, 1) } while $x = int($x / $base);
411 $str = reverse $str if $big_endian;
427 return "-" if not exists $sequence_num{$$op};
428 return base_n($sequence_num{$$op});
432 my($op, $sub, $level) = @_;
434 if ($op->flags & OPf_KIDS) {
435 for (my $kid = $op->first; $$kid; $kid = $kid->sibling) {
436 walk_topdown($kid, $sub, $level + 1);
439 elsif (class($op) eq "PMOP") {
440 my $maybe_root = $op->pmreplroot;
441 if (ref($maybe_root) and $maybe_root->isa("B::OP")) {
442 # It really is the root of the replacement, not something
443 # else stored here for lack of space elsewhere
444 walk_topdown($maybe_root, $sub, $level + 1);
450 my($ar, $level) = @_;
452 if (ref($l) eq "ARRAY") {
453 walklines($l, $level + 1);
461 my($top, $level) = @_;
464 my @todo = ([$top, \@lines]);
465 while (@todo and my($op, $targ) = @{shift @todo}) {
466 for (; $$op; $op = $op->next) {
467 last if $opsseen{$$op}++;
469 my $name = $op->name;
470 if (class($op) eq "LOGOP") {
473 push @todo, [$op->other, $ar];
474 } elsif ($name eq "subst" and $ {$op->pmreplstart}) {
477 push @todo, [$op->pmreplstart, $ar];
478 } elsif ($name =~ /^enter(loop|iter)$/) {
480 $labels{${$op->nextop}} = "NEXT";
481 $labels{${$op->lastop}} = "LAST";
482 $labels{${$op->redoop}} = "REDO";
484 $labels{$op->nextop->seq} = "NEXT";
485 $labels{$op->lastop->seq} = "LAST";
486 $labels{$op->redoop->seq} = "REDO";
491 walklines(\@lines, 0);
494 # The structure of this routine is purposely modeled after op.c's peep()
498 return if class($op) eq "NULL" or exists $sequence_num{$$op};
499 for (; $$op; $op = $op->next) {
500 last if exists $sequence_num{$$op};
501 my $name = $op->name;
502 if ($name =~ /^(null|scalar|lineseq|scope)$/) {
503 next if $oldop and $ {$op->next};
505 $sequence_num{$$op} = $seq_max++;
506 if (class($op) eq "LOGOP") {
507 my $other = $op->other;
508 $other = $other->next while $other->name eq "null";
510 } elsif (class($op) eq "LOOP") {
511 my $redoop = $op->redoop;
512 $redoop = $redoop->next while $redoop->name eq "null";
514 my $nextop = $op->nextop;
515 $nextop = $nextop->next while $nextop->name eq "null";
517 my $lastop = $op->lastop;
518 $lastop = $lastop->next while $lastop->name eq "null";
520 } elsif ($name eq "subst" and $ {$op->pmreplstart}) {
521 my $replstart = $op->pmreplstart;
522 $replstart = $replstart->next while $replstart->name eq "null";
523 sequence($replstart);
530 sub fmt_line { # generate text-line for op.
531 my($hr, $op, $text, $level) = @_;
533 $_->($hr, $op, \$text, \$level, $stylename) for @callbacks;
535 return '' if $hr->{SKIP}; # suppress line if a callback said so
536 return '' if $hr->{goto} and $hr->{goto} eq '-'; # no goto nowhere
538 # spec: (?(text1#varText2)?)
539 $text =~ s/\(\?\(([^\#]*?)\#(\w+)([^\#]*?)\)\?\)/
540 $hr->{$2} ? $1.$hr->{$2}.$3 : ""/eg;
542 # spec: (x(exec_text;basic_text)x)
543 $text =~ s/\(x\((.*?);(.*?)\)x\)/$order eq "exec" ? $1 : $2/egs;
546 $text =~ s/\(\*\(([^;]*?)\)\*\)/$1 x $level/egs;
548 # spec: (*(text1;text2)*)
549 $text =~ s/\(\*\((.*?);(.*?)\)\*\)/$1 x ($level - 1) . $2 x ($level>0)/egs;
551 # convert #Var to tag=>val form: Var\t#var
552 $text =~ s/\#([A-Z][a-z]+)(\d+)?/\t\u$1\t\L#$1$2/gs;
555 $text =~ s/\#([a-zA-Z]+)(\d+)/sprintf("%-$2s", $hr->{$1})/eg;
557 $text =~ s/\#([a-zA-Z]+)/$hr->{$1}/eg; # populate #var's
558 $text =~ s/[ \t]*~+[ \t]*/ /g; # squeeze tildes
560 $text = "# $hr->{src}\n$text" if $show_src and $hr->{src};
563 return "$text\n" if $text ne "";
564 return $text; # suppress empty lines
567 our %priv; # used to display each opcode's BASEOP.op_private values
569 $priv{$_}{128} = "LVINTRO"
570 for ("pos", "substr", "vec", "threadsv", "gvsv", "rv2sv", "rv2hv", "rv2gv",
571 "rv2av", "rv2arylen", "aelem", "helem", "aslice", "hslice", "padsv",
572 "padav", "padhv", "enteriter");
573 $priv{$_}{64} = "REFC" for ("leave", "leavesub", "leavesublv", "leavewrite");
574 $priv{"aassign"}{64} = "COMMON";
575 $priv{"aassign"}{32} = $] < 5.009 ? "PHASH" : "STATE";
576 $priv{"sassign"}{32} = "STATE";
577 $priv{"sassign"}{64} = "BKWARD";
578 $priv{$_}{64} = "RTIME" for ("match", "subst", "substcont", "qr");
579 @{$priv{"trans"}}{1,2,4,8,16,64} = ("<UTF", ">UTF", "IDENT", "SQUASH", "DEL",
581 $priv{"repeat"}{64} = "DOLIST";
582 $priv{"leaveloop"}{64} = "CONT";
583 @{$priv{$_}}{32,64,96} = ("DREFAV", "DREFHV", "DREFSV")
584 for (qw(rv2gv rv2sv padsv aelem helem));
585 $priv{$_}{16} = "STATE" for ("padav", "padhv", "padsv");
586 @{$priv{"entersub"}}{16,32,64} = ("DBG","TARG","NOMOD");
587 @{$priv{$_}}{4,8,128} = ("INARGS","AMPER","NO()") for ("entersub", "rv2cv");
588 $priv{"gv"}{32} = "EARLYCV";
589 $priv{"aelem"}{16} = $priv{"helem"}{16} = "LVDEFER";
590 $priv{$_}{16} = "OURINTR" for ("gvsv", "rv2sv", "rv2av", "rv2hv", "r2gv",
592 $priv{$_}{16} = "TARGMY"
593 for (map(($_,"s$_"),"chop", "chomp"),
594 map(($_,"i_$_"), "postinc", "postdec", "multiply", "divide", "modulo",
595 "add", "subtract", "negate"), "pow", "concat", "stringify",
596 "left_shift", "right_shift", "bit_and", "bit_xor", "bit_or",
597 "complement", "atan2", "sin", "cos", "rand", "exp", "log", "sqrt",
598 "int", "hex", "oct", "abs", "length", "index", "rindex", "sprintf",
599 "ord", "chr", "crypt", "quotemeta", "join", "push", "unshift", "flock",
600 "chdir", "chown", "chroot", "unlink", "chmod", "utime", "rename",
601 "link", "symlink", "mkdir", "rmdir", "wait", "waitpid", "system",
602 "exec", "kill", "getppid", "getpgrp", "setpgrp", "getpriority",
603 "setpriority", "time", "sleep");
604 $priv{$_}{4} = "REVERSED" for ("enteriter", "iter");
605 @{$priv{"const"}}{4,8,16,32,64,128} = ("SHORT","STRICT","ENTERED",'$[',"BARE","WARN");
606 $priv{"flip"}{64} = $priv{"flop"}{64} = "LINENUM";
607 $priv{"list"}{64} = "GUESSED";
608 $priv{"delete"}{64} = "SLICE";
609 $priv{"exists"}{64} = "SUB";
610 @{$priv{"sort"}}{1,2,4,8,16,32,64} = ("NUM", "INT", "REV", "INPLACE","DESC","QSORT","STABLE");
611 $priv{"threadsv"}{64} = "SVREFd";
612 @{$priv{$_}}{16,32,64,128} = ("INBIN","INCR","OUTBIN","OUTCR")
613 for ("open", "backtick");
614 $priv{"exit"}{128} = "VMS";
615 $priv{$_}{2} = "FTACCESS"
616 for ("ftrread", "ftrwrite", "ftrexec", "fteread", "ftewrite", "fteexec");
617 $priv{"entereval"}{2} = "HAS_HH";
619 # Stacked filetests are post 5.8.x
620 $priv{$_}{4} = "FTSTACKED"
621 for ("ftrread", "ftrwrite", "ftrexec", "fteread", "ftewrite", "fteexec",
622 "ftis", "fteowned", "ftrowned", "ftzero", "ftsize", "ftmtime",
623 "ftatime", "ftctime", "ftsock", "ftchr", "ftblk", "ftfile", "ftdir",
624 "ftpipe", "ftlink", "ftsuid", "ftsgid", "ftsvtx", "fttty", "fttext",
626 # Lexical $_ is post 5.8.x
627 $priv{$_}{2} = "GREPLEX"
628 for ("mapwhile", "mapstart", "grepwhile", "grepstart");
631 our %hints; # used to display each COP's op_hints values
633 # strict refs, subs, vars
634 @hints{2,512,1024} = ('$', '&', '*');
635 # integers, locale, bytes, arybase
636 @hints{1,4,8,16,32} = ('i', 'l', 'b', '[');
637 # block scope, localise %^H, $^OPEN (in), $^OPEN (out)
638 @hints{256,131072,262144,524288} = ('{','%','<','>');
639 # overload new integer, float, binary, string, re
640 @hints{4096,8192,16384,32768,65536} = ('I', 'F', 'B', 'S', 'R');
642 @hints{1048576,2097152} = ('T', 'E');
643 # filetest access, UTF-8
644 @hints{4194304,8388608} = ('X', 'U');
649 for my $flag (sort {$b <=> $a} keys %$hash) {
650 if ($hash->{$flag} and $x & $flag and $x >= $flag) {
652 push @s, $hash->{$flag};
656 return join(",", @s);
661 _flags($priv{$name}, $x);
670 my($sv, $hr, $preferpv) = @_;
671 $hr->{svclass} = class($sv);
672 $hr->{svclass} = "UV"
673 if $hr->{svclass} eq "IV" and $sv->FLAGS & SVf_IVisUV;
674 Carp::cluck("bad concise_sv: $sv") unless $sv and $$sv;
675 $hr->{svaddr} = sprintf("%#x", $$sv);
676 if ($hr->{svclass} eq "GV") {
678 my $stash = $gv->STASH->NAME;
679 if ($stash eq "main") {
682 $stash = $stash . "::";
684 $hr->{svval} = "*$stash" . $gv->SAFENAME;
685 return "*$stash" . $gv->SAFENAME;
687 while (class($sv) eq "RV") {
688 $hr->{svval} .= "\\";
691 if (class($sv) eq "SPECIAL") {
692 $hr->{svval} .= ["Null", "sv_undef", "sv_yes", "sv_no"]->[$$sv];
693 } elsif ($preferpv && $sv->FLAGS & SVf_POK) {
694 $hr->{svval} .= cstring($sv->PV);
695 } elsif ($sv->FLAGS & SVf_NOK) {
696 $hr->{svval} .= $sv->NV;
697 } elsif ($sv->FLAGS & SVf_IOK) {
698 $hr->{svval} .= $sv->int_value;
699 } elsif ($sv->FLAGS & SVf_POK) {
700 $hr->{svval} .= cstring($sv->PV);
701 } elsif (class($sv) eq "HV") {
702 $hr->{svval} .= 'HASH';
705 $hr->{svval} = 'undef' unless defined $hr->{svval};
706 my $out = $hr->{svclass};
707 return $out .= " $hr->{svval}" ;
715 warn "-e not yet supported\n" and return if $file eq '-e';
717 or warn "# $file: $!, (chdirs not supported by this feature yet)\n"
721 unshift @l, $file; # like @{_<$filename} in debug, array starts at 1
722 $srclines{$file} = \@l;
726 my ($op, $level, $format) = @_;
728 $h{exname} = $h{name} = $op->name;
729 $h{NAME} = uc $h{name};
730 $h{class} = class($op);
731 $h{extarg} = $h{targ} = $op->targ;
732 $h{extarg} = "" unless $h{extarg};
733 if ($h{name} eq "null" and $h{targ}) {
734 # targ holds the old type
735 $h{exname} = "ex-" . substr(ppname($h{targ}), 3);
737 } elsif ($op->name =~ /^leave(sub(lv)?|write)?$/) {
738 # targ potentially holds a reference count
739 if ($op->private & 64) {
740 my $refs = "ref" . ($h{targ} != 1 ? "s" : "");
741 $h{targarglife} = $h{targarg} = "$h{targ} $refs";
744 my $padname = (($curcv->PADLIST->ARRAY)[0]->ARRAY)[$h{targ}];
745 if (defined $padname and class($padname) ne "SPECIAL") {
746 $h{targarg} = $padname->PVX;
747 if ($padname->FLAGS & SVf_FAKE) {
749 $h{targarglife} = "$h{targarg}:FAKE";
751 # These changes relate to the jumbo closure fix.
752 # See changes 19939 and 20005
755 if $padname->PARENT_FAKELEX_FLAGS & PAD_FAKELEX_ANON;
757 if $padname->PARENT_FAKELEX_FLAGS & PAD_FAKELEX_MULTI;
758 $fake .= ':' . $padname->PARENT_PAD_INDEX
759 if $curcv->CvFLAGS & CVf_ANON;
760 $h{targarglife} = "$h{targarg}:FAKE:$fake";
764 my $intro = $padname->COP_SEQ_RANGE_LOW - $cop_seq_base;
765 my $finish = int($padname->COP_SEQ_RANGE_HIGH) - $cop_seq_base;
766 $finish = "end" if $finish == 999999999 - $cop_seq_base;
767 $h{targarglife} = "$h{targarg}:$intro,$finish";
770 $h{targarglife} = $h{targarg} = "t" . $h{targ};
774 $h{svclass} = $h{svaddr} = $h{svval} = "";
775 if ($h{class} eq "PMOP") {
776 my $precomp = $op->precomp;
777 if (defined $precomp) {
778 $precomp = cstring($precomp); # Escape literal control sequences
779 $precomp = "/$precomp/";
783 my $pmreplroot = $op->pmreplroot;
785 if (ref($pmreplroot) eq "B::GV") {
786 # with C<@stash_array = split(/pat/, str);>,
787 # *stash_array is stored in /pat/'s pmreplroot.
788 $h{arg} = "($precomp => \@" . $pmreplroot->NAME . ")";
789 } elsif (!ref($pmreplroot) and $pmreplroot) {
790 # same as the last case, except the value is actually a
791 # pad offset for where the GV is kept (this happens under
793 my $gv = (($curcv->PADLIST->ARRAY)[1]->ARRAY)[$pmreplroot];
794 $h{arg} = "($precomp => \@" . $gv->NAME . ")";
795 } elsif ($ {$op->pmreplstart}) {
797 $pmreplstart = "replstart->" . seq($op->pmreplstart);
798 $h{arg} = "(" . join(" ", $precomp, $pmreplstart) . ")";
800 $h{arg} = "($precomp)";
802 } elsif ($h{class} eq "PVOP" and $h{name} ne "trans") {
803 $h{arg} = '("' . $op->pv . '")';
804 $h{svval} = '"' . $op->pv . '"';
805 } elsif ($h{class} eq "COP") {
806 my $label = $op->label;
807 $h{coplabel} = $label;
808 $label = $label ? "$label: " : "";
811 $loc .= ":" . $op->line;
812 my($stash, $cseq) = ($op->stash->NAME, $op->cop_seq - $cop_seq_base);
813 my $arybase = $op->arybase;
814 $arybase = $arybase ? ' $[=' . $arybase : "";
815 $h{arg} = "($label$stash $cseq $loc$arybase)";
817 my ($file,$ln) = split /:/, $loc;
818 fill_srclines($file) unless exists $srclines{$file};
819 $h{src} = "$ln: " . $srclines{$file}[$ln];
820 # print "$file:$ln $h{src}\n";
822 } elsif ($h{class} eq "LOOP") {
823 $h{arg} = "(next->" . seq($op->nextop) . " last->" . seq($op->lastop)
824 . " redo->" . seq($op->redoop) . ")";
825 } elsif ($h{class} eq "LOGOP") {
827 $h{arg} = "(other->" . seq($op->other) . ")";
829 elsif ($h{class} eq "SVOP" or $h{class} eq "PADOP") {
830 unless ($h{name} eq 'aelemfast' and $op->flags & OPf_SPECIAL) {
831 my $idx = ($h{class} eq "SVOP") ? $op->targ : $op->padix;
832 my $preferpv = $h{name} eq "method_named";
833 if ($h{class} eq "PADOP" or !${$op->sv}) {
834 my $sv = (($curcv->PADLIST->ARRAY)[1]->ARRAY)[$idx];
835 $h{arg} = "[" . concise_sv($sv, \%h, $preferpv) . "]";
836 $h{targarglife} = $h{targarg} = "";
838 $h{arg} = "(" . concise_sv($op->sv, \%h, $preferpv) . ")";
842 $h{seq} = $h{hyphseq} = seq($op);
843 $h{seq} = "" if $h{seq} eq "-";
846 $h{label} = $labels{$$op};
848 $h{seqnum} = $op->seq;
849 $h{label} = $labels{$op->seq};
851 $h{next} = $op->next;
852 $h{next} = (class($h{next}) eq "NULL") ? "(end)" : seq($h{next});
853 $h{nextaddr} = sprintf("%#x", $ {$op->next});
854 $h{sibaddr} = sprintf("%#x", $ {$op->sibling});
855 $h{firstaddr} = sprintf("%#x", $ {$op->first}) if $op->can("first");
856 $h{lastaddr} = sprintf("%#x", $ {$op->last}) if $op->can("last");
858 $h{classsym} = $opclass{$h{class}};
859 $h{flagval} = $op->flags;
860 $h{flags} = op_flags($op->flags);
861 $h{privval} = $op->private;
862 $h{private} = private_flags($h{name}, $op->private);
863 if ($op->can("hints")) {
864 $h{hintsval} = $op->hints;
865 $h{hints} = hints_flags($h{hintsval});
867 $h{hintsval} = $h{hints} = '';
869 $h{addr} = sprintf("%#x", $$op);
870 $h{typenum} = $op->type;
871 $h{noise} = $linenoise[$op->type];
873 return fmt_line(\%h, $op, $format, $level);
877 my($op, $level) = @_;
878 if ($order eq "exec" and $lastnext and $$lastnext != $$op) {
879 # insert a 'goto' line
880 my $synth = {"seq" => seq($lastnext), "class" => class($lastnext),
881 "addr" => sprintf("%#x", $$lastnext),
882 "goto" => seq($lastnext), # simplify goto '-' removal
884 print $walkHandle fmt_line($synth, $op, $gotofmt, $level+1);
886 $lastnext = $op->next;
887 print $walkHandle concise_op($op, $level, $format);
890 # B::OP::terse (see Terse.pm) now just calls this
892 my($op, $level) = @_;
894 # This isn't necessarily right, but there's no easy way to get
895 # from an OP to the right CV. This is a limitation of the
896 # ->terse() interface style, and there isn't much to do about
897 # it. In particular, we can die in concise_op if the main pad
898 # isn't long enough, or has the wrong kind of entries, compared to
899 # the pad a sub was compiled with. The fix for that would be to
900 # make a backwards compatible "terse" format that never even
901 # looked at the pad, just like the old B::Terse. I don't think
902 # that's worth the effort, though.
903 $curcv = main_cv unless $curcv;
905 if ($order eq "exec" and $lastnext and $$lastnext != $$op) {
907 my $h = {"seq" => seq($lastnext), "class" => class($lastnext),
908 "addr" => sprintf("%#x", $$lastnext)};
910 fmt_line($h, $op, $style{"terse"}[1], $level+1);
912 $lastnext = $op->next;
914 concise_op($op, $level, $style{"terse"}[0]);
920 my $style = $tree_decorations[$tree_style];
921 my($space, $single, $kids, $kid, $nokid, $last, $lead, $size) = @$style;
922 my $name = concise_op($op, $level, $treefmt);
923 if (not $op->flags & OPf_KIDS) {
927 for (my $kid = $op->first; $$kid; $kid = $kid->sibling) {
928 push @lines, tree($kid, $level+1);
931 for ($i = $#lines; substr($lines[$i], 0, 1) eq " "; $i--) {
932 $lines[$i] = $space . $lines[$i];
935 $lines[$i] = $last . $lines[$i];
937 if (substr($lines[$i], 0, 1) eq " ") {
938 $lines[$i] = $nokid . $lines[$i];
940 $lines[$i] = $kid . $lines[$i];
943 $lines[$i] = $kids . $lines[$i];
945 $lines[0] = $single . $lines[0];
947 return("$name$lead" . shift @lines,
948 map(" " x (length($name)+$size) . $_, @lines));
951 # *** Warning: fragile kludge ahead ***
952 # Because the B::* modules run in the same interpreter as the code
953 # they're compiling, their presence tends to distort the view we have of
954 # the code we're looking at. In particular, perl gives sequence numbers
955 # to COPs. If the program we're looking at were run on its own, this
956 # would start at 1. Because all of B::Concise and all the modules it
957 # uses are compiled first, though, by the time we get to the user's
958 # program the sequence number is already pretty high, which could be
959 # distracting if you're trying to tell OPs apart. Therefore we'd like to
960 # subtract an offset from all the sequence numbers we display, to
961 # restore the simpler view of the world. The trick is to know what that
962 # offset will be, when we're still compiling B::Concise! If we
963 # hardcoded a value, it would have to change every time B::Concise or
964 # other modules we use do. To help a little, what we do here is compile
965 # a little code at the end of the module, and compute the base sequence
966 # number for the user's program as being a small offset later, so all we
967 # have to worry about are changes in the offset.
969 # [For 5.8.x and earlier perl is generating sequence numbers for all ops,
970 # and using them to reference labels]
973 # When you say "perl -MO=Concise -e '$a'", the output should look like:
975 # 4 <@> leave[t1] vKP/REFC ->(end)
977 #^ smallest OP sequence number should be 1
978 # 2 <;> nextstate(main 1 -e:1) v ->3
979 # ^ smallest COP sequence number should be 1
980 # - <1> ex-rv2sv vK/1 ->4
981 # 3 <$> gvsv(*a) s ->4
983 # If the second of the marked numbers there isn't 1, it means you need
984 # to update the corresponding magic number in the next line.
985 # Remember, this needs to stay the last things in the module.
987 # Why is this different for MacOS? Does it matter?
988 my $cop_seq_mnum = $^O eq 'MacOS' ? 12 : 11;
989 $cop_seq_base = svref_2object(eval 'sub{0;}')->START->cop_seq + $cop_seq_mnum;
997 B::Concise - Walk Perl syntax tree, printing concise info about ops
1001 perl -MO=Concise[,OPTIONS] foo.pl
1003 use B::Concise qw(set_style add_callback);
1007 This compiler backend prints the internal OPs of a Perl program's syntax
1008 tree in one of several space-efficient text formats suitable for debugging
1009 the inner workings of perl or other compiler backends. It can print OPs in
1010 the order they appear in the OP tree, in the order they will execute, or
1011 in a text approximation to their tree structure, and the format of the
1012 information displayed is customizable. Its function is similar to that of
1013 perl's B<-Dx> debugging flag or the B<B::Terse> module, but it is more
1014 sophisticated and flexible.
1018 Here's two outputs (or 'renderings'), using the -exec and -basic
1019 (i.e. default) formatting conventions on the same code snippet.
1021 % perl -MO=Concise,-exec -e '$a = $b + 42'
1023 2 <;> nextstate(main 1 -e:1) v
1025 4 <$> const[IV 42] s
1026 * 5 <2> add[t3] sK/2
1029 8 <@> leave[1 ref] vKP/REFC
1031 In this -exec rendering, each opcode is executed in the order shown.
1032 The add opcode, marked with '*', is discussed in more detail.
1034 The 1st column is the op's sequence number, starting at 1, and is
1035 displayed in base 36 by default. Here they're purely linear; the
1036 sequences are very helpful when looking at code with loops and
1039 The symbol between angle brackets indicates the op's type, for
1040 example; <2> is a BINOP, <@> a LISTOP, and <#> is a PADOP, which is
1041 used in threaded perls. (see L</"OP class abbreviations">).
1043 The opname, as in B<'add[t1]'>, may be followed by op-specific
1044 information in parentheses or brackets (ex B<'[t1]'>).
1046 The op-flags (ex B<'sK/2'>) are described in (L</"OP flags
1049 % perl -MO=Concise -e '$a = $b + 42'
1050 8 <@> leave[1 ref] vKP/REFC ->(end)
1052 2 <;> nextstate(main 1 -e:1) v ->3
1053 7 <2> sassign vKS/2 ->8
1054 * 5 <2> add[t1] sK/2 ->6
1055 - <1> ex-rv2sv sK/1 ->4
1056 3 <$> gvsv(*b) s ->4
1057 4 <$> const(IV 42) s ->5
1058 - <1> ex-rv2sv sKRM*/1 ->7
1059 6 <$> gvsv(*a) s ->7
1061 The default rendering is top-down, so they're not in execution order.
1062 This form reflects the way the stack is used to parse and evaluate
1063 expressions; the add operates on the two terms below it in the tree.
1065 Nullops appear as C<ex-opname>, where I<opname> is an op that has been
1066 optimized away by perl. They're displayed with a sequence-number of
1067 '-', because they are not executed (they don't appear in previous
1068 example), they're printed here because they reflect the parse.
1070 The arrow points to the sequence number of the next op; they're not
1071 displayed in -exec mode, for obvious reasons.
1073 Note that because this rendering was done on a non-threaded perl, the
1074 PADOPs in the previous examples are now SVOPs, and some (but not all)
1075 of the square brackets have been replaced by round ones. This is a
1076 subtle feature to provide some visual distinction between renderings
1077 on threaded and un-threaded perls.
1082 Arguments that don't start with a hyphen are taken to be the names of
1083 subroutines to print the OPs of; if no such functions are specified,
1084 the main body of the program (outside any subroutines, and not
1085 including use'd or require'd files) is rendered. Passing C<BEGIN>,
1086 C<UNITCHECK>, C<CHECK>, C<INIT>, or C<END> will cause all of the
1087 corresponding special blocks to be printed.
1089 Options affect how things are rendered (ie printed). They're presented
1090 here by their visual effect, 1st being strongest. They're grouped
1091 according to how they interrelate; within each group the options are
1092 mutually exclusive (unless otherwise stated).
1094 =head2 Options for Opcode Ordering
1096 These options control the 'vertical display' of opcodes. The display
1097 'order' is also called 'mode' elsewhere in this document.
1103 Print OPs in the order they appear in the OP tree (a preorder
1104 traversal, starting at the root). The indentation of each OP shows its
1105 level in the tree, and the '->' at the end of the line indicates the
1106 next opcode in execution order. This mode is the default, so the flag
1107 is included simply for completeness.
1111 Print OPs in the order they would normally execute (for the majority
1112 of constructs this is a postorder traversal of the tree, ending at the
1113 root). In most cases the OP that usually follows a given OP will
1114 appear directly below it; alternate paths are shown by indentation. In
1115 cases like loops when control jumps out of a linear path, a 'goto'
1120 Print OPs in a text approximation of a tree, with the root of the tree
1121 at the left and 'left-to-right' order of children transformed into
1122 'top-to-bottom'. Because this mode grows both to the right and down,
1123 it isn't suitable for large programs (unless you have a very wide
1128 =head2 Options for Line-Style
1130 These options select the line-style (or just style) used to render
1131 each opcode, and dictates what info is actually printed into each line.
1137 Use the author's favorite set of formatting conventions. This is the
1142 Use formatting conventions that emulate the output of B<B::Terse>. The
1143 basic mode is almost indistinguishable from the real B<B::Terse>, and the
1144 exec mode looks very similar, but is in a more logical order and lacks
1145 curly brackets. B<B::Terse> doesn't have a tree mode, so the tree mode
1146 is only vaguely reminiscent of B<B::Terse>.
1150 Use formatting conventions in which the name of each OP, rather than being
1151 written out in full, is represented by a one- or two-character abbreviation.
1152 This is mainly a joke.
1156 Use formatting conventions reminiscent of B<B::Debug>; these aren't
1157 very concise at all.
1161 Use formatting conventions read from the environment variables
1162 C<B_CONCISE_FORMAT>, C<B_CONCISE_GOTO_FORMAT>, and C<B_CONCISE_TREE_FORMAT>.
1166 =head2 Options for tree-specific formatting
1172 Use a tree format in which the minimum amount of space is used for the
1173 lines connecting nodes (one character in most cases). This squeezes out
1174 a few precious columns of screen real estate.
1178 Use a tree format that uses longer edges to separate OP nodes. This format
1179 tends to look better than the compact one, especially in ASCII, and is
1184 Use tree connecting characters drawn from the VT100 line-drawing set.
1185 This looks better if your terminal supports it.
1189 Draw the tree with standard ASCII characters like C<+> and C<|>. These don't
1190 look as clean as the VT100 characters, but they'll work with almost any
1191 terminal (or the horizontal scrolling mode of less(1)) and are suitable
1192 for text documentation or email. This is the default.
1196 These are pairwise exclusive, i.e. compact or loose, vt or ascii.
1198 =head2 Options controlling sequence numbering
1204 Print OP sequence numbers in base I<n>. If I<n> is greater than 10, the
1205 digit for 11 will be 'a', and so on. If I<n> is greater than 36, the digit
1206 for 37 will be 'A', and so on until 62. Values greater than 62 are not
1207 currently supported. The default is 36.
1211 Print sequence numbers with the most significant digit first. This is the
1212 usual convention for Arabic numerals, and the default.
1214 =item B<-littleendian>
1216 Print seqence numbers with the least significant digit first. This is
1217 obviously mutually exclusive with bigendian.
1221 =head2 Other options
1227 With this option, the rendering of each statement (starting with the
1228 nextstate OP) will be preceded by the 1st line of source code that
1229 generates it. For example:
1233 2 <;> nextstate(main 1 junk.pl:1) v:{
1234 3 <0> padsv[$i:1,10] vM/LVINTRO
1235 # 3: for $i (0..9) {
1236 4 <;> nextstate(main 3 junk.pl:3) v:{
1240 8 <{> enteriter(next->j last->m redo->9)[$i:1,10] lKS
1242 l <|> and(other->9) vK/1
1244 9 <;> nextstate(main 2 junk.pl:4) v
1246 b <$> const[PV "line "] s
1253 The following options are pairwise exclusive.
1259 Include the main program in the output, even if subroutines were also
1260 specified. This rendering is normally suppressed when a subroutine
1261 name or reference is given.
1265 This restores the default behavior after you've changed it with '-main'
1266 (it's not normally needed). If no subroutine name/ref is given, main is
1267 rendered, regardless of this flag.
1271 Renderings usually include a banner line identifying the function name
1272 or stringified subref. This suppresses the printing of the banner.
1274 TBC: Remove the stringified coderef; while it provides a 'cookie' for
1275 each function rendered, the cookies used should be 1,2,3.. not a
1276 random hex-address. It also complicates string comparison of two
1281 restores default banner behavior.
1283 =item B<-banneris> => subref
1285 TBC: a hookpoint (and an option to set it) for a user-supplied
1286 function to produce a banner appropriate for users needs. It's not
1287 ideal, because the rendering-state variables, which are a natural
1288 candidate for use in concise.t, are unavailable to the user.
1292 =head2 Option Stickiness
1294 If you invoke Concise more than once in a program, you should know that
1295 the options are 'sticky'. This means that the options you provide in
1296 the first call will be remembered for the 2nd call, unless you
1297 re-specify or change them.
1299 =head1 ABBREVIATIONS
1301 The concise style uses symbols to convey maximum info with minimal
1302 clutter (like hex addresses). With just a little practice, you can
1303 start to see the flowers, not just the branches, in the trees.
1305 =head2 OP class abbreviations
1307 These symbols appear before the op-name, and indicate the
1308 B:: namespace that represents the ops in your Perl code.
1310 0 OP (aka BASEOP) An OP with no children
1311 1 UNOP An OP with one child
1312 2 BINOP An OP with two children
1313 | LOGOP A control branch OP
1314 @ LISTOP An OP that could have lots of children
1315 / PMOP An OP with a regular expression
1316 $ SVOP An OP with an SV
1317 " PVOP An OP with a string
1318 { LOOP An OP that holds pointers for a loop
1319 ; COP An OP that marks the start of a statement
1320 # PADOP An OP with a GV on the pad
1322 =head2 OP flags abbreviations
1324 OP flags are either public or private. The public flags alter the
1325 behavior of each opcode in consistent ways, and are represented by 0
1326 or more single characters.
1328 v OPf_WANT_VOID Want nothing (void context)
1329 s OPf_WANT_SCALAR Want single value (scalar context)
1330 l OPf_WANT_LIST Want list of any length (list context)
1332 K OPf_KIDS There is a firstborn child.
1333 P OPf_PARENS This operator was parenthesized.
1334 (Or block needs explicit scope entry.)
1335 R OPf_REF Certified reference.
1336 (Return container, not containee).
1337 M OPf_MOD Will modify (lvalue).
1338 S OPf_STACKED Some arg is arriving on the stack.
1339 * OPf_SPECIAL Do something weird for this op (see op.h)
1341 Private flags, if any are set for an opcode, are displayed after a '/'
1343 8 <@> leave[1 ref] vKP/REFC ->(end)
1344 7 <2> sassign vKS/2 ->8
1346 They're opcode specific, and occur less often than the public ones, so
1347 they're represented by short mnemonics instead of single-chars; see
1348 F<op.h> for gory details, or try this quick 2-liner:
1350 $> perl -MB::Concise -de 1
1351 DB<1> |x \%B::Concise::priv
1353 =head1 FORMATTING SPECIFICATIONS
1355 For each line-style ('concise', 'terse', 'linenoise', etc.) there are
1356 3 format-specs which control how OPs are rendered.
1358 The first is the 'default' format, which is used in both basic and exec
1359 modes to print all opcodes. The 2nd, goto-format, is used in exec
1360 mode when branches are encountered. They're not real opcodes, and are
1361 inserted to look like a closing curly brace. The tree-format is tree
1364 When a line is rendered, the correct format-spec is copied and scanned
1365 for the following items; data is substituted in, and other
1366 manipulations like basic indenting are done, for each opcode rendered.
1368 There are 3 kinds of items that may be populated; special patterns,
1369 #vars, and literal text, which is copied verbatim. (Yes, it's a set
1372 =head2 Special Patterns
1374 These items are the primitives used to perform indenting, and to
1375 select text from amongst alternatives.
1379 =item B<(x(>I<exec_text>B<;>I<basic_text>B<)x)>
1381 Generates I<exec_text> in exec mode, or I<basic_text> in basic mode.
1383 =item B<(*(>I<text>B<)*)>
1385 Generates one copy of I<text> for each indentation level.
1387 =item B<(*(>I<text1>B<;>I<text2>B<)*)>
1389 Generates one fewer copies of I<text1> than the indentation level, followed
1390 by one copy of I<text2> if the indentation level is more than 0.
1392 =item B<(?(>I<text1>B<#>I<var>I<Text2>B<)?)>
1394 If the value of I<var> is true (not empty or zero), generates the
1395 value of I<var> surrounded by I<text1> and I<Text2>, otherwise
1400 Any number of tildes and surrounding whitespace will be collapsed to
1407 These #vars represent opcode properties that you may want as part of
1408 your rendering. The '#' is intended as a private sigil; a #var's
1409 value is interpolated into the style-line, much like "read $this".
1411 These vars take 3 forms:
1417 A property named 'var' is assumed to exist for the opcodes, and is
1418 interpolated into the rendering.
1420 =item B<#>I<var>I<N>
1422 Generates the value of I<var>, left justified to fill I<N> spaces.
1423 Note that this means while you can have properties 'foo' and 'foo2',
1424 you cannot render 'foo2', but you could with 'foo2a'. You would be
1425 wise not to rely on this behavior going forward ;-)
1429 This ucfirst form of #var generates a tag-value form of itself for
1430 display; it converts '#Var' into a 'Var => #var' style, which is then
1431 handled as described above. (Imp-note: #Vars cannot be used for
1432 conditional-fills, because the => #var transform is done after the check
1437 The following variables are 'defined' by B::Concise; when they are
1438 used in a style, their respective values are plugged into the
1439 rendering of each opcode.
1441 Only some of these are used by the standard styles, the others are
1442 provided for you to delve into optree mechanics, should you wish to
1443 add a new style (see L</add_style> below) that uses them. You can
1444 also add new ones using L</add_callback>.
1450 The address of the OP, in hexadecimal.
1454 The OP-specific information of the OP (such as the SV for an SVOP, the
1455 non-local exit pointers for a LOOP, etc.) enclosed in parentheses.
1459 The B-determined class of the OP, in all caps.
1463 A single symbol abbreviating the class of the OP.
1467 The label of the statement or block the OP is the start of, if any.
1471 The name of the OP, or 'ex-foo' if the OP is a null that used to be a foo.
1475 The target of the OP, or nothing for a nulled OP.
1479 The address of the OP's first child, in hexadecimal.
1483 The OP's flags, abbreviated as a series of symbols.
1487 The numeric value of the OP's flags.
1491 The COP's hint flags, rendered with abbreviated names if possible. An empty
1492 string if this is not a COP.
1496 The numeric value of the COP's hint flags, or an empty string if this is not
1501 The sequence number of the OP, or a hyphen if it doesn't have one.
1505 'NEXT', 'LAST', or 'REDO' if the OP is a target of one of those in exec
1506 mode, or empty otherwise.
1510 The address of the OP's last child, in hexadecimal.
1518 The OP's name, in all caps.
1522 The sequence number of the OP's next OP.
1526 The address of the OP's next OP, in hexadecimal.
1530 A one- or two-character abbreviation for the OP's name.
1534 The OP's private flags, rendered with abbreviated names if possible.
1538 The numeric value of the OP's private flags.
1542 The sequence number of the OP. Note that this is a sequence number
1543 generated by B::Concise.
1547 5.8.x and earlier only. 5.9 and later do not provide this.
1549 The real sequence number of the OP, as a regular number and not adjusted
1550 to be relative to the start of the real program. (This will generally be
1551 a fairly large number because all of B<B::Concise> is compiled before
1556 Whether or not the op has been optimised by the peephole optimiser.
1558 Only available in 5.9 and later.
1562 The address of the OP's next youngest sibling, in hexadecimal.
1566 The address of the OP's SV, if it has an SV, in hexadecimal.
1570 The class of the OP's SV, if it has one, in all caps (e.g., 'IV').
1574 The value of the OP's SV, if it has one, in a short human-readable format.
1578 The numeric value of the OP's targ.
1582 The name of the variable the OP's targ refers to, if any, otherwise the
1583 letter t followed by the OP's targ in decimal.
1585 =item B<#targarglife>
1587 Same as B<#targarg>, but followed by the COP sequence numbers that delimit
1588 the variable's lifetime (or 'end' for a variable in an open scope) for a
1593 The numeric value of the OP's type, in decimal.
1597 =head1 One-Liner Command tips
1601 =item perl -MO=Concise,bar foo.pl
1603 Renders only bar() from foo.pl. To see main, drop the ',bar'. To see
1606 =item perl -MDigest::MD5=md5 -MO=Concise,md5 -e1
1608 Identifies md5 as an XS function. The export is needed so that BC can
1611 =item perl -MPOSIX -MO=Concise,_POSIX_ARG_MAX -e1
1613 Identifies _POSIX_ARG_MAX as a constant sub, optimized to an IV.
1614 Although POSIX isn't entirely consistent across platforms, this is
1615 likely to be present in virtually all of them.
1617 =item perl -MPOSIX -MO=Concise,a -e 'print _POSIX_SAVED_IDS'
1619 This renders a print statement, which includes a call to the function.
1620 It's identical to rendering a file with a use call and that single
1621 statement, except for the filename which appears in the nextstate ops.
1623 =item perl -MPOSIX -MO=Concise,a -e 'sub a{_POSIX_SAVED_IDS}'
1625 This is B<very> similar to previous, only the first two ops differ. This
1626 subroutine rendering is more representative, insofar as a single main
1627 program will have many subs.
1632 =head1 Using B::Concise outside of the O framework
1634 The common (and original) usage of B::Concise was for command-line
1635 renderings of simple code, as given in EXAMPLE. But you can also use
1636 B<B::Concise> from your code, and call compile() directly, and
1637 repeatedly. By doing so, you can avoid the compile-time only
1638 operation of O.pm, and even use the debugger to step through
1639 B::Concise::compile() itself.
1641 Once you're doing this, you may alter Concise output by adding new
1642 rendering styles, and by optionally adding callback routines which
1643 populate new variables, if such were referenced from those (just
1646 =head2 Example: Altering Concise Renderings
1648 use B::Concise qw(set_style add_callback);
1649 add_style($yourStyleName => $defaultfmt, $gotofmt, $treefmt);
1652 my ($h, $op, $format, $level, $stylename) = @_;
1653 $h->{variable} = some_func($op);
1655 $walker = B::Concise::compile(@options,@subnames,@subrefs);
1660 B<set_style> accepts 3 arguments, and updates the three format-specs
1661 comprising a line-style (basic-exec, goto, tree). It has one minor
1662 drawback though; it doesn't register the style under a new name. This
1663 can become an issue if you render more than once and switch styles.
1664 Thus you may prefer to use add_style() and/or set_style_standard()
1667 =head2 set_style_standard($name)
1669 This restores one of the standard line-styles: C<terse>, C<concise>,
1670 C<linenoise>, C<debug>, C<env>, into effect. It also accepts style
1671 names previously defined with add_style().
1675 This subroutine accepts a new style name and three style arguments as
1676 above, and creates, registers, and selects the newly named style. It is
1677 an error to re-add a style; call set_style_standard() to switch between
1680 =head2 add_callback()
1682 If your newly minted styles refer to any new #variables, you'll need
1683 to define a callback subroutine that will populate (or modify) those
1684 variables. They are then available for use in the style you've
1687 The callbacks are called for each opcode visited by Concise, in the
1688 same order as they are added. Each subroutine is passed five
1691 1. A hashref, containing the variable names and values which are
1692 populated into the report-line for the op
1693 2. the op, as a B<B::OP> object
1694 3. a reference to the format string
1695 4. the formatting (indent) level
1696 5. the selected stylename
1698 To define your own variables, simply add them to the hash, or change
1699 existing values if you need to. The level and format are passed in as
1700 references to scalars, but it is unlikely that they will need to be
1701 changed or even used.
1703 =head2 Running B::Concise::compile()
1705 B<compile> accepts options as described above in L</OPTIONS>, and
1706 arguments, which are either coderefs, or subroutine names.
1708 It constructs and returns a $treewalker coderef, which when invoked,
1709 traverses, or walks, and renders the optrees of the given arguments to
1710 STDOUT. You can reuse this, and can change the rendering style used
1711 each time; thereafter the coderef renders in the new style.
1713 B<walk_output> lets you change the print destination from STDOUT to
1714 another open filehandle, or into a string passed as a ref (unless
1715 you've built perl with -Uuseperlio).
1717 my $walker = B::Concise::compile('-terse','aFuncName', \&aSubRef); # 1
1718 walk_output(\my $buf);
1719 $walker->(); # 1 renders -terse
1720 set_style_standard('concise'); # 2
1721 $walker->(); # 2 renders -concise
1722 $walker->(@new); # 3 renders whatever
1723 print "3 different renderings: terse, concise, and @new: $buf\n";
1725 When $walker is called, it traverses the subroutines supplied when it
1726 was created, and renders them using the current style. You can change
1727 the style afterwards in several different ways:
1729 1. call C<compile>, altering style or mode/order
1730 2. call C<set_style_standard>
1731 3. call $walker, passing @new options
1733 Passing new options to the $walker is the easiest way to change
1734 amongst any pre-defined styles (the ones you add are automatically
1735 recognized as options), and is the only way to alter rendering order
1736 without calling compile again. Note however that rendering state is
1737 still shared amongst multiple $walker objects, so they must still be
1738 used in a coordinated manner.
1740 =head2 B::Concise::reset_sequence()
1742 This function (not exported) lets you reset the sequence numbers (note
1743 that they're numbered arbitrarily, their goal being to be human
1744 readable). Its purpose is mostly to support testing, i.e. to compare
1745 the concise output from two identical anonymous subroutines (but
1746 different instances). Without the reset, B::Concise, seeing that
1747 they're separate optrees, generates different sequence numbers in
1752 Errors in rendering (non-existent function-name, non-existent coderef)
1753 are written to the STDOUT, or wherever you've set it via
1756 Errors using the various *style* calls, and bad args to walk_output(),
1757 result in die(). Use an eval if you wish to catch these errors and
1758 continue processing.
1762 Stephen McCamant, E<lt>smcc@CSUA.Berkeley.EDUE<gt>.