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Diffstat (limited to 'Master/tlpkg/tlperl/lib/B/Concise.pm')
| -rw-r--r-- | Master/tlpkg/tlperl/lib/B/Concise.pm | 1628 |
1 files changed, 1628 insertions, 0 deletions
diff --git a/Master/tlpkg/tlperl/lib/B/Concise.pm b/Master/tlpkg/tlperl/lib/B/Concise.pm new file mode 100644 index 00000000000..c84578e44c4 --- /dev/null +++ b/Master/tlpkg/tlperl/lib/B/Concise.pm @@ -0,0 +1,1628 @@ +package B::Concise; +# Copyright (C) 2000-2003 Stephen McCamant. All rights reserved. +# This program is free software; you can redistribute and/or modify it +# under the same terms as Perl itself. + +# Note: we need to keep track of how many use declarations/BEGIN +# blocks this module uses, so we can avoid printing them when user +# asks for the BEGIN blocks in her program. Update the comments and +# the count in concise_specials if you add or delete one. The +# -MO=Concise counts as use #1. + +use strict; # use #2 +use warnings; # uses #3 and #4, since warnings uses Carp + +use Exporter (); # use #5 + +our $VERSION = "0.66"; +our @ISA = qw(Exporter); +our @EXPORT_OK = qw( set_style set_style_standard add_callback + concise_subref concise_cv concise_main + add_style walk_output compile reset_sequence ); +our %EXPORT_TAGS = + ( io => [qw( walk_output compile reset_sequence )], + style => [qw( add_style set_style_standard )], + cb => [qw( add_callback )], + mech => [qw( concise_subref concise_cv concise_main )], ); + +# use #6 +use B qw(class ppname main_start main_root main_cv cstring svref_2object + SVf_IOK SVf_NOK SVf_POK SVf_IVisUV SVf_FAKE OPf_KIDS OPf_SPECIAL + CVf_ANON); + +my %style = + ("terse" => + ["(?(#label =>\n)?)(*( )*)#class (#addr) #name (?([#targ])?) " + . "#svclass~(?((#svaddr))?)~#svval~(?(label \"#coplabel\")?)\n", + "(*( )*)goto #class (#addr)\n", + "#class pp_#name"], + "concise" => + ["#hyphseq2 (*( (x( ;)x))*)<#classsym> " + . "#exname#arg(?([#targarglife])?)~#flags(?(/#private)?)(x(;~->#next)x)\n" + , " (*( )*) goto #seq\n", + "(?(<#seq>)?)#exname#arg(?([#targarglife])?)"], + "linenoise" => + ["(x(;(*( )*))x)#noise#arg(?([#targarg])?)(x( ;\n)x)", + "gt_#seq ", + "(?(#seq)?)#noise#arg(?([#targarg])?)"], + "debug" => + ["#class (#addr)\n\top_next\t\t#nextaddr\n\top_sibling\t#sibaddr\n\t" + . "op_ppaddr\tPL_ppaddr[OP_#NAME]\n\top_type\t\t#typenum\n" . + ($] > 5.009 ? '' : "\top_seq\t\t#seqnum\n") + . "\top_flags\t#flagval\n\top_private\t#privval\n" + . "(?(\top_first\t#firstaddr\n)?)(?(\top_last\t\t#lastaddr\n)?)" + . "(?(\top_sv\t\t#svaddr\n)?)", + " GOTO #addr\n", + "#addr"], + "env" => [$ENV{B_CONCISE_FORMAT}, $ENV{B_CONCISE_GOTO_FORMAT}, + $ENV{B_CONCISE_TREE_FORMAT}], + ); + +# Renderings, ie how Concise prints, is controlled by these vars +# primary: +our $stylename; # selects current style from %style +my $order = "basic"; # how optree is walked & printed: basic, exec, tree + +# rendering mechanics: +# these 'formats' are the line-rendering templates +# they're updated from %style when $stylename changes +my ($format, $gotofmt, $treefmt); + +# lesser players: +my $base = 36; # how <sequence#> is displayed +my $big_endian = 1; # more <sequence#> display +my $tree_style = 0; # tree-order details +my $banner = 1; # print banner before optree is traversed +my $do_main = 0; # force printing of main routine + +# another factor: can affect all styles! +our @callbacks; # allow external management + +set_style_standard("concise"); + +my $curcv; +my $cop_seq_base; + +sub set_style { + ($format, $gotofmt, $treefmt) = @_; + #warn "set_style: deprecated, use set_style_standard instead\n"; # someday + die "expecting 3 style-format args\n" unless @_ == 3; +} + +sub add_style { + my ($newstyle,@args) = @_; + die "style '$newstyle' already exists, choose a new name\n" + if exists $style{$newstyle}; + die "expecting 3 style-format args\n" unless @args == 3; + $style{$newstyle} = [@args]; + $stylename = $newstyle; # update rendering state +} + +sub set_style_standard { + ($stylename) = @_; # update rendering state + die "err: style '$stylename' unknown\n" unless exists $style{$stylename}; + set_style(@{$style{$stylename}}); +} + +sub add_callback { + push @callbacks, @_; +} + +# output handle, used with all Concise-output printing +our $walkHandle; # public for your convenience +BEGIN { $walkHandle = \*STDOUT } + +sub walk_output { # updates $walkHandle + my $handle = shift; + return $walkHandle unless $handle; # allow use as accessor + + if (ref $handle eq 'SCALAR') { + require Config; + die "no perlio in this build, can't call walk_output (\\\$scalar)\n" + unless $Config::Config{useperlio}; + # in 5.8+, open(FILEHANDLE,MODE,REFERENCE) writes to string + open my $tmp, '>', $handle; # but cant re-set existing STDOUT + $walkHandle = $tmp; # so use my $tmp as intermediate var + return $walkHandle; + } + my $iotype = ref $handle; + die "expecting argument/object that can print\n" + unless $iotype eq 'GLOB' or $iotype and $handle->can('print'); + $walkHandle = $handle; +} + +sub concise_subref { + my($order, $coderef, $name) = @_; + my $codeobj = svref_2object($coderef); + + return concise_stashref(@_) + unless ref $codeobj eq 'B::CV'; + concise_cv_obj($order, $codeobj, $name); +} + +sub concise_stashref { + my($order, $h) = @_; + foreach my $k (sort keys %$h) { + local *s = $h->{$k}; + my $coderef = *s{CODE} or next; + reset_sequence(); + print "FUNC: ", *s, "\n"; + my $codeobj = svref_2object($coderef); + next unless ref $codeobj eq 'B::CV'; + eval { concise_cv_obj($order, $codeobj) } + or warn "err $@ on $codeobj"; + } +} + +# This should have been called concise_subref, but it was exported +# under this name in versions before 0.56 +*concise_cv = \&concise_subref; + +sub concise_cv_obj { + my ($order, $cv, $name) = @_; + # name is either a string, or a CODE ref (copy of $cv arg??) + + $curcv = $cv; + if ($cv->XSUB) { + print $walkHandle "$name is XS code\n"; + return; + } + if (class($cv->START) eq "NULL") { + no strict 'refs'; + if (ref $name eq 'CODE') { + print $walkHandle "coderef $name has no START\n"; + } + elsif (exists &$name) { + print $walkHandle "$name exists in stash, but has no START\n"; + } + else { + print $walkHandle "$name not in symbol table\n"; + } + return; + } + sequence($cv->START); + if ($order eq "exec") { + walk_exec($cv->START); + } + elsif ($order eq "basic") { + # walk_topdown($cv->ROOT, sub { $_[0]->concise($_[1]) }, 0); + my $root = $cv->ROOT; + unless (ref $root eq 'B::NULL') { + walk_topdown($root, sub { $_[0]->concise($_[1]) }, 0); + } else { + print $walkHandle "B::NULL encountered doing ROOT on $cv. avoiding disaster\n"; + } + } else { + print $walkHandle tree($cv->ROOT, 0); + } +} + +sub concise_main { + my($order) = @_; + sequence(main_start); + $curcv = main_cv; + if ($order eq "exec") { + return if class(main_start) eq "NULL"; + walk_exec(main_start); + } elsif ($order eq "tree") { + return if class(main_root) eq "NULL"; + print $walkHandle tree(main_root, 0); + } elsif ($order eq "basic") { + return if class(main_root) eq "NULL"; + walk_topdown(main_root, + sub { $_[0]->concise($_[1]) }, 0); + } +} + +sub concise_specials { + my($name, $order, @cv_s) = @_; + my $i = 1; + if ($name eq "BEGIN") { + splice(@cv_s, 0, 8); # skip 7 BEGIN blocks in this file. NOW 8 ?? + } elsif ($name eq "CHECK") { + pop @cv_s; # skip the CHECK block that calls us + } + for my $cv (@cv_s) { + print $walkHandle "$name $i:\n"; + $i++; + concise_cv_obj($order, $cv, $name); + } +} + +my $start_sym = "\e(0"; # "\cN" sometimes also works +my $end_sym = "\e(B"; # "\cO" respectively + +my @tree_decorations = + ([" ", "--", "+-", "|-", "| ", "`-", "-", 1], + [" ", "-", "+", "+", "|", "`", "", 0], + [" ", map("$start_sym$_$end_sym", "qq", "wq", "tq", "x ", "mq", "q"), 1], + [" ", map("$start_sym$_$end_sym", "q", "w", "t", "x", "m"), "", 0], + ); + + +sub compileOpts { + # set rendering state from options and args + my (@options,@args); + if (@_) { + @options = grep(/^-/, @_); + @args = grep(!/^-/, @_); + } + for my $o (@options) { + # mode/order + if ($o eq "-basic") { + $order = "basic"; + } elsif ($o eq "-exec") { + $order = "exec"; + } elsif ($o eq "-tree") { + $order = "tree"; + } + # tree-specific + elsif ($o eq "-compact") { + $tree_style |= 1; + } elsif ($o eq "-loose") { + $tree_style &= ~1; + } elsif ($o eq "-vt") { + $tree_style |= 2; + } elsif ($o eq "-ascii") { + $tree_style &= ~2; + } + # sequence numbering + elsif ($o =~ /^-base(\d+)$/) { + $base = $1; + } elsif ($o eq "-bigendian") { + $big_endian = 1; + } elsif ($o eq "-littleendian") { + $big_endian = 0; + } + elsif ($o eq "-nobanner") { + $banner = 0; + } elsif ($o eq "-banner") { + $banner = 1; + } + elsif ($o eq "-main") { + $do_main = 1; + } elsif ($o eq "-nomain") { + $do_main = 0; + } + # line-style options + elsif (exists $style{substr($o, 1)}) { + $stylename = substr($o, 1); + set_style_standard($stylename); + } else { + warn "Option $o unrecognized"; + } + } + return (@args); +} + +sub compile { + my (@args) = compileOpts(@_); + return sub { + my @newargs = compileOpts(@_); # accept new rendering options + warn "disregarding non-options: @newargs\n" if @newargs; + + for my $objname (@args) { + next unless $objname; # skip null args to avoid noisy responses + + if ($objname eq "BEGIN") { + concise_specials("BEGIN", $order, + B::begin_av->isa("B::AV") ? + B::begin_av->ARRAY : ()); + } elsif ($objname eq "INIT") { + concise_specials("INIT", $order, + B::init_av->isa("B::AV") ? + B::init_av->ARRAY : ()); + } elsif ($objname eq "CHECK") { + concise_specials("CHECK", $order, + B::check_av->isa("B::AV") ? + B::check_av->ARRAY : ()); + } elsif ($objname eq "END") { + concise_specials("END", $order, + B::end_av->isa("B::AV") ? + B::end_av->ARRAY : ()); + } + else { + # convert function names to subrefs + my $objref; + if (ref $objname) { + print $walkHandle "B::Concise::compile($objname)\n" + if $banner; + $objref = $objname; + } else { + $objname = "main::" . $objname unless $objname =~ /::/; + print $walkHandle "$objname:\n"; + no strict 'refs'; + unless (exists &$objname) { + print $walkHandle "err: unknown function ($objname)\n"; + return; + } + $objref = \&$objname; + } + concise_subref($order, $objref, $objname); + } + } + if (!@args or $do_main) { + print $walkHandle "main program:\n" if $do_main; + concise_main($order); + } + return @args; # something + } +} + +my %labels; +my $lastnext; # remembers op-chain, used to insert gotos + +my %opclass = ('OP' => "0", 'UNOP' => "1", 'BINOP' => "2", 'LOGOP' => "|", + 'LISTOP' => "@", 'PMOP' => "/", 'SVOP' => "\$", 'GVOP' => "*", + 'PVOP' => '"', 'LOOP' => "{", 'COP' => ";", 'PADOP' => "#"); + +no warnings 'qw'; # "Possible attempt to put comments..."; use #7 +my @linenoise = + qw'# () sc ( @? 1 $* gv *{ m$ m@ m% m? p/ *$ $ $# & a& pt \\ s\\ rf bl + ` *? <> ?? ?/ r/ c/ // qr s/ /c y/ = @= C sC Cp sp df un BM po +1 +I + -1 -I 1+ I+ 1- I- ** * i* / i/ %$ i% x + i+ - i- . " << >> < i< + > i> <= i, >= i. == i= != i! <? i? s< s> s, s. s= s! s? b& b^ b| -0 -i + ! ~ a2 si cs rd sr e^ lg sq in %x %o ab le ss ve ix ri sf FL od ch cy + uf lf uc lc qm @ [f [ @[ eh vl ky dl ex % ${ @{ uk pk st jn ) )[ a@ + a% sl +] -] [- [+ so rv GS GW MS MW .. f. .f && || ^^ ?: &= |= -> s{ s} + v} ca wa di rs ;; ; ;d }{ { } {} f{ it {l l} rt }l }n }r dm }g }e ^o + ^c ^| ^# um bm t~ u~ ~d DB db ^s se ^g ^r {w }w pf pr ^O ^K ^R ^W ^d ^v + ^e ^t ^k t. fc ic fl .s .p .b .c .l .a .h g1 s1 g2 s2 ?. l? -R -W -X -r + -w -x -e -o -O -z -s -M -A -C -S -c -b -f -d -p -l -u -g -k -t -T -B cd + co cr u. cm ut r. l@ s@ r@ mD uD oD rD tD sD wD cD f$ w$ p$ sh e$ k$ g3 + g4 s4 g5 s5 T@ C@ L@ G@ A@ S@ Hg Hc Hr Hw Mg Mc Ms Mr Sg Sc So rq do {e + e} {t t} g6 G6 6e g7 G7 7e g8 G8 8e g9 G9 9e 6s 7s 8s 9s 6E 7E 8E 9E Pn + Pu GP SP EP Gn Gg GG SG EG g0 c$ lk t$ ;s n> // /= CO'; + +my $chars = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"; + +sub op_flags { # common flags (see BASOP.op_flags in op.h) + my($x) = @_; + my(@v); + push @v, "v" if ($x & 3) == 1; + push @v, "s" if ($x & 3) == 2; + push @v, "l" if ($x & 3) == 3; + push @v, "K" if $x & 4; + push @v, "P" if $x & 8; + push @v, "R" if $x & 16; + push @v, "M" if $x & 32; + push @v, "S" if $x & 64; + push @v, "*" if $x & 128; + return join("", @v); +} + +sub base_n { + my $x = shift; + return "-" . base_n(-$x) if $x < 0; + my $str = ""; + do { $str .= substr($chars, $x % $base, 1) } while $x = int($x / $base); + $str = reverse $str if $big_endian; + return $str; +} + +my %sequence_num; +my $seq_max = 1; + +sub reset_sequence { + # reset the sequence + %sequence_num = (); + $seq_max = 1; + $lastnext = 0; +} + +sub seq { + my($op) = @_; + return "-" if not exists $sequence_num{$$op}; + return base_n($sequence_num{$$op}); +} + +sub walk_topdown { + my($op, $sub, $level) = @_; + $sub->($op, $level); + if ($op->flags & OPf_KIDS) { + for (my $kid = $op->first; $$kid; $kid = $kid->sibling) { + walk_topdown($kid, $sub, $level + 1); + } + } + elsif (class($op) eq "PMOP") { + my $maybe_root = $op->pmreplroot; + if (ref($maybe_root) and $maybe_root->isa("B::OP")) { + # It really is the root of the replacement, not something + # else stored here for lack of space elsewhere + walk_topdown($maybe_root, $sub, $level + 1); + } + } +} + +sub walklines { + my($ar, $level) = @_; + for my $l (@$ar) { + if (ref($l) eq "ARRAY") { + walklines($l, $level + 1); + } else { + $l->concise($level); + } + } +} + +sub walk_exec { + my($top, $level) = @_; + my %opsseen; + my @lines; + my @todo = ([$top, \@lines]); + while (@todo and my($op, $targ) = @{shift @todo}) { + for (; $$op; $op = $op->next) { + last if $opsseen{$$op}++; + push @$targ, $op; + my $name = $op->name; + if (class($op) eq "LOGOP") { + my $ar = []; + push @$targ, $ar; + push @todo, [$op->other, $ar]; + } elsif ($name eq "subst" and $ {$op->pmreplstart}) { + my $ar = []; + push @$targ, $ar; + push @todo, [$op->pmreplstart, $ar]; + } elsif ($name =~ /^enter(loop|iter)$/) { + if ($] > 5.009) { + $labels{${$op->nextop}} = "NEXT"; + $labels{${$op->lastop}} = "LAST"; + $labels{${$op->redoop}} = "REDO"; + } else { + $labels{$op->nextop->seq} = "NEXT"; + $labels{$op->lastop->seq} = "LAST"; + $labels{$op->redoop->seq} = "REDO"; + } + } + } + } + walklines(\@lines, 0); +} + +# The structure of this routine is purposely modeled after op.c's peep() +sub sequence { + my($op) = @_; + my $oldop = 0; + return if class($op) eq "NULL" or exists $sequence_num{$$op}; + for (; $$op; $op = $op->next) { + last if exists $sequence_num{$$op}; + my $name = $op->name; + if ($name =~ /^(null|scalar|lineseq|scope)$/) { + next if $oldop and $ {$op->next}; + } else { + $sequence_num{$$op} = $seq_max++; + if (class($op) eq "LOGOP") { + my $other = $op->other; + $other = $other->next while $other->name eq "null"; + sequence($other); + } elsif (class($op) eq "LOOP") { + my $redoop = $op->redoop; + $redoop = $redoop->next while $redoop->name eq "null"; + sequence($redoop); + my $nextop = $op->nextop; + $nextop = $nextop->next while $nextop->name eq "null"; + sequence($nextop); + my $lastop = $op->lastop; + $lastop = $lastop->next while $lastop->name eq "null"; + sequence($lastop); + } elsif ($name eq "subst" and $ {$op->pmreplstart}) { + my $replstart = $op->pmreplstart; + $replstart = $replstart->next while $replstart->name eq "null"; + sequence($replstart); + } + } + $oldop = $op; + } +} + +sub fmt_line { # generate text-line for op. + my($hr, $op, $text, $level) = @_; + + $_->($hr, $op, \$text, \$level, $stylename) for @callbacks; + + return '' if $hr->{SKIP}; # suppress line if a callback said so + return '' if $hr->{goto} and $hr->{goto} eq '-'; # no goto nowhere + + # spec: (?(text1#varText2)?) + $text =~ s/\(\?\(([^\#]*?)\#(\w+)([^\#]*?)\)\?\)/ + $hr->{$2} ? $1.$hr->{$2}.$3 : ""/eg; + + # spec: (x(exec_text;basic_text)x) + $text =~ s/\(x\((.*?);(.*?)\)x\)/$order eq "exec" ? $1 : $2/egs; + + # spec: (*(text)*) + $text =~ s/\(\*\(([^;]*?)\)\*\)/$1 x $level/egs; + + # spec: (*(text1;text2)*) + $text =~ s/\(\*\((.*?);(.*?)\)\*\)/$1 x ($level - 1) . $2 x ($level>0)/egs; + + # convert #Var to tag=>val form: Var\t#var + $text =~ s/\#([A-Z][a-z]+)(\d+)?/\t\u$1\t\L#$1$2/gs; + + # spec: #varN + $text =~ s/\#([a-zA-Z]+)(\d+)/sprintf("%-$2s", $hr->{$1})/eg; + + $text =~ s/\#([a-zA-Z]+)/$hr->{$1}/eg; # populate #var's + $text =~ s/[ \t]*~+[ \t]*/ /g; # squeeze tildes + chomp $text; + return "$text\n" if $text ne ""; + return $text; # suppress empty lines +} + +our %priv; # used to display each opcode's BASEOP.op_private values + +$priv{$_}{128} = "LVINTRO" + for ("pos", "substr", "vec", "threadsv", "gvsv", "rv2sv", "rv2hv", "rv2gv", + "rv2av", "rv2arylen", "aelem", "helem", "aslice", "hslice", "padsv", + "padav", "padhv", "enteriter"); +$priv{$_}{64} = "REFC" for ("leave", "leavesub", "leavesublv", "leavewrite"); +$priv{"aassign"}{64} = "COMMON"; +$priv{"aassign"}{32} = "PHASH" if $] < 5.009; +$priv{"sassign"}{64} = "BKWARD"; +$priv{$_}{64} = "RTIME" for ("match", "subst", "substcont", "qr"); +@{$priv{"trans"}}{1,2,4,8,16,64} = ("<UTF", ">UTF", "IDENT", "SQUASH", "DEL", + "COMPL", "GROWS"); +$priv{"repeat"}{64} = "DOLIST"; +$priv{"leaveloop"}{64} = "CONT"; +@{$priv{$_}}{32,64,96} = ("DREFAV", "DREFHV", "DREFSV") + for (qw(rv2gv rv2sv padsv aelem helem)); +@{$priv{"entersub"}}{16,32,64} = ("DBG","TARG","NOMOD"); +@{$priv{$_}}{4,8,128} = ("INARGS","AMPER","NO()") for ("entersub", "rv2cv"); +$priv{"gv"}{32} = "EARLYCV"; +$priv{"aelem"}{16} = $priv{"helem"}{16} = "LVDEFER"; +$priv{$_}{16} = "OURINTR" for ("gvsv", "rv2sv", "rv2av", "rv2hv", "r2gv", + "enteriter"); +$priv{$_}{16} = "TARGMY" + for (map(($_,"s$_"),"chop", "chomp"), + map(($_,"i_$_"), "postinc", "postdec", "multiply", "divide", "modulo", + "add", "subtract", "negate"), "pow", "concat", "stringify", + "left_shift", "right_shift", "bit_and", "bit_xor", "bit_or", + "complement", "atan2", "sin", "cos", "rand", "exp", "log", "sqrt", + "int", "hex", "oct", "abs", "length", "index", "rindex", "sprintf", + "ord", "chr", "crypt", "quotemeta", "join", "push", "unshift", "flock", + "chdir", "chown", "chroot", "unlink", "chmod", "utime", "rename", + "link", "symlink", "mkdir", "rmdir", "wait", "waitpid", "system", + "exec", "kill", "getppid", "getpgrp", "setpgrp", "getpriority", + "setpriority", "time", "sleep"); +$priv{$_}{4} = "REVERSED" for ("enteriter", "iter"); +@{$priv{"const"}}{4,8,16,32,64,128} = ("SHORT","STRICT","ENTERED",'$[',"BARE","WARN"); +$priv{"flip"}{64} = $priv{"flop"}{64} = "LINENUM"; +$priv{"list"}{64} = "GUESSED"; +$priv{"delete"}{64} = "SLICE"; +$priv{"exists"}{64} = "SUB"; +$priv{$_}{64} = "LOCALE" + for ("sort", "prtf", "sprintf", "slt", "sle", "seq", "sne", "sgt", "sge", + "scmp", "lc", "uc", "lcfirst", "ucfirst"); +@{$priv{"sort"}}{1,2,4,8,16} = ("NUM", "INT", "REV", "INPLACE","DESC"); +$priv{"threadsv"}{64} = "SVREFd"; +@{$priv{$_}}{16,32,64,128} = ("INBIN","INCR","OUTBIN","OUTCR") + for ("open", "backtick"); +$priv{"exit"}{128} = "VMS"; +$priv{$_}{2} = "FTACCESS" + for ("ftrread", "ftrwrite", "ftrexec", "fteread", "ftewrite", "fteexec"); +if ($] >= 5.009) { + # Stacked filetests are post 5.8.x + $priv{$_}{4} = "FTSTACKED" + for ("ftrread", "ftrwrite", "ftrexec", "fteread", "ftewrite", "fteexec", + "ftis", "fteowned", "ftrowned", "ftzero", "ftsize", "ftmtime", + "ftatime", "ftctime", "ftsock", "ftchr", "ftblk", "ftfile", "ftdir", + "ftpipe", "ftlink", "ftsuid", "ftsgid", "ftsvtx", "fttty", "fttext", + "ftbinary"); + # Lexical $_ is post 5.8.x + $priv{$_}{2} = "GREPLEX" + for ("mapwhile", "mapstart", "grepwhile", "grepstart"); +} + +sub private_flags { + my($name, $x) = @_; + my @s; + for my $flag (128, 96, 64, 32, 16, 8, 4, 2, 1) { + if ($priv{$name}{$flag} and $x & $flag and $x >= $flag) { + $x -= $flag; + push @s, $priv{$name}{$flag}; + } + } + push @s, $x if $x; + return join(",", @s); +} + +sub concise_sv { + my($sv, $hr, $preferpv) = @_; + $hr->{svclass} = class($sv); + $hr->{svclass} = "UV" + if $hr->{svclass} eq "IV" and $sv->FLAGS & SVf_IVisUV; + Carp::cluck("bad concise_sv: $sv") unless $sv and $$sv; + $hr->{svaddr} = sprintf("%#x", $$sv); + if ($hr->{svclass} eq "GV") { + my $gv = $sv; + my $stash = $gv->STASH->NAME; + if ($stash eq "main") { + $stash = ""; + } else { + $stash = $stash . "::"; + } + $hr->{svval} = "*$stash" . $gv->SAFENAME; + return "*$stash" . $gv->SAFENAME; + } else { + while (class($sv) eq "RV") { + $hr->{svval} .= "\\"; + $sv = $sv->RV; + } + if (class($sv) eq "SPECIAL") { + $hr->{svval} .= ["Null", "sv_undef", "sv_yes", "sv_no"]->[$$sv]; + } elsif ($preferpv && $sv->FLAGS & SVf_POK) { + $hr->{svval} .= cstring($sv->PV); + } elsif ($sv->FLAGS & SVf_NOK) { + $hr->{svval} .= $sv->NV; + } elsif ($sv->FLAGS & SVf_IOK) { + $hr->{svval} .= $sv->int_value; + } elsif ($sv->FLAGS & SVf_POK) { + $hr->{svval} .= cstring($sv->PV); + } elsif (class($sv) eq "HV") { + $hr->{svval} .= 'HASH'; + } + + $hr->{svval} = 'undef' unless defined $hr->{svval}; + my $out = $hr->{svclass}; + return $out .= " $hr->{svval}" ; + } +} + +sub concise_op { + my ($op, $level, $format) = @_; + my %h; + $h{exname} = $h{name} = $op->name; + $h{NAME} = uc $h{name}; + $h{class} = class($op); + $h{extarg} = $h{targ} = $op->targ; + $h{extarg} = "" unless $h{extarg}; + if ($h{name} eq "null" and $h{targ}) { + # targ holds the old type + $h{exname} = "ex-" . substr(ppname($h{targ}), 3); + $h{extarg} = ""; + } elsif ($op->name =~ /^leave(sub(lv)?|write)?$/) { + # targ potentially holds a reference count + if ($op->private & 64) { + my $refs = "ref" . ($h{targ} != 1 ? "s" : ""); + $h{targarglife} = $h{targarg} = "$h{targ} $refs"; + } + } elsif ($h{targ}) { + my $padname = (($curcv->PADLIST->ARRAY)[0]->ARRAY)[$h{targ}]; + if (defined $padname and class($padname) ne "SPECIAL") { + $h{targarg} = $padname->PVX; + if ($padname->FLAGS & SVf_FAKE) { + if ($] < 5.009) { + $h{targarglife} = "$h{targarg}:FAKE"; + } else { + # These changes relate to the jumbo closure fix. + # See changes 19939 and 20005 + my $fake = ''; + $fake .= 'a' if $padname->IVX & 1; # PAD_FAKELEX_ANON + $fake .= 'm' if $padname->IVX & 2; # PAD_FAKELEX_MULTI + $fake .= ':' . $padname->NVX if $curcv->CvFLAGS & CVf_ANON; + $h{targarglife} = "$h{targarg}:FAKE:$fake"; + } + } + else { + my $intro = $padname->NVX - $cop_seq_base; + my $finish = int($padname->IVX) - $cop_seq_base; + $finish = "end" if $finish == 999999999 - $cop_seq_base; + $h{targarglife} = "$h{targarg}:$intro,$finish"; + } + } else { + $h{targarglife} = $h{targarg} = "t" . $h{targ}; + } + } + $h{arg} = ""; + $h{svclass} = $h{svaddr} = $h{svval} = ""; + if ($h{class} eq "PMOP") { + my $precomp = $op->precomp; + if (defined $precomp) { + $precomp = cstring($precomp); # Escape literal control sequences + $precomp = "/$precomp/"; + } else { + $precomp = ""; + } + my $pmreplroot = $op->pmreplroot; + my $pmreplstart; + if (ref($pmreplroot) eq "B::GV") { + # with C<@stash_array = split(/pat/, str);>, + # *stash_array is stored in /pat/'s pmreplroot. + $h{arg} = "($precomp => \@" . $pmreplroot->NAME . ")"; + } elsif (!ref($pmreplroot) and $pmreplroot) { + # same as the last case, except the value is actually a + # pad offset for where the GV is kept (this happens under + # ithreads) + my $gv = (($curcv->PADLIST->ARRAY)[1]->ARRAY)[$pmreplroot]; + $h{arg} = "($precomp => \@" . $gv->NAME . ")"; + } elsif ($ {$op->pmreplstart}) { + undef $lastnext; + $pmreplstart = "replstart->" . seq($op->pmreplstart); + $h{arg} = "(" . join(" ", $precomp, $pmreplstart) . ")"; + } else { + $h{arg} = "($precomp)"; + } + } elsif ($h{class} eq "PVOP" and $h{name} ne "trans") { + $h{arg} = '("' . $op->pv . '")'; + $h{svval} = '"' . $op->pv . '"'; + } elsif ($h{class} eq "COP") { + my $label = $op->label; + $h{coplabel} = $label; + $label = $label ? "$label: " : ""; + my $loc = $op->file; + $loc =~ s[.*/][]; + $loc .= ":" . $op->line; + my($stash, $cseq) = ($op->stash->NAME, $op->cop_seq - $cop_seq_base); + my $arybase = $op->arybase; + $arybase = $arybase ? ' $[=' . $arybase : ""; + $h{arg} = "($label$stash $cseq $loc$arybase)"; + } elsif ($h{class} eq "LOOP") { + $h{arg} = "(next->" . seq($op->nextop) . " last->" . seq($op->lastop) + . " redo->" . seq($op->redoop) . ")"; + } elsif ($h{class} eq "LOGOP") { + undef $lastnext; + $h{arg} = "(other->" . seq($op->other) . ")"; + } + elsif ($h{class} eq "SVOP" or $h{class} eq "PADOP") { + unless ($h{name} eq 'aelemfast' and $op->flags & OPf_SPECIAL) { + my $idx = ($h{class} eq "SVOP") ? $op->targ : $op->padix; + my $preferpv = $h{name} eq "method_named"; + if ($h{class} eq "PADOP" or !${$op->sv}) { + my $sv = (($curcv->PADLIST->ARRAY)[1]->ARRAY)[$idx]; + $h{arg} = "[" . concise_sv($sv, \%h, $preferpv) . "]"; + $h{targarglife} = $h{targarg} = ""; + } else { + $h{arg} = "(" . concise_sv($op->sv, \%h, $preferpv) . ")"; + } + } + } + $h{seq} = $h{hyphseq} = seq($op); + $h{seq} = "" if $h{seq} eq "-"; + if ($] > 5.009) { + $h{opt} = $op->opt; + $h{static} = $op->static; + $h{label} = $labels{$$op}; + } else { + $h{seqnum} = $op->seq; + $h{label} = $labels{$op->seq}; + } + $h{next} = $op->next; + $h{next} = (class($h{next}) eq "NULL") ? "(end)" : seq($h{next}); + $h{nextaddr} = sprintf("%#x", $ {$op->next}); + $h{sibaddr} = sprintf("%#x", $ {$op->sibling}); + $h{firstaddr} = sprintf("%#x", $ {$op->first}) if $op->can("first"); + $h{lastaddr} = sprintf("%#x", $ {$op->last}) if $op->can("last"); + + $h{classsym} = $opclass{$h{class}}; + $h{flagval} = $op->flags; + $h{flags} = op_flags($op->flags); + $h{privval} = $op->private; + $h{private} = private_flags($h{name}, $op->private); + $h{addr} = sprintf("%#x", $$op); + $h{typenum} = $op->type; + $h{noise} = $linenoise[$op->type]; + + return fmt_line(\%h, $op, $format, $level); +} + +sub B::OP::concise { + my($op, $level) = @_; + if ($order eq "exec" and $lastnext and $$lastnext != $$op) { + # insert a 'goto' line + my $synth = {"seq" => seq($lastnext), "class" => class($lastnext), + "addr" => sprintf("%#x", $$lastnext), + "goto" => seq($lastnext), # simplify goto '-' removal + }; + print $walkHandle fmt_line($synth, $op, $gotofmt, $level+1); + } + $lastnext = $op->next; + print $walkHandle concise_op($op, $level, $format); +} + +# B::OP::terse (see Terse.pm) now just calls this +sub b_terse { + my($op, $level) = @_; + + # This isn't necessarily right, but there's no easy way to get + # from an OP to the right CV. This is a limitation of the + # ->terse() interface style, and there isn't much to do about + # it. In particular, we can die in concise_op if the main pad + # isn't long enough, or has the wrong kind of entries, compared to + # the pad a sub was compiled with. The fix for that would be to + # make a backwards compatible "terse" format that never even + # looked at the pad, just like the old B::Terse. I don't think + # that's worth the effort, though. + $curcv = main_cv unless $curcv; + + if ($order eq "exec" and $lastnext and $$lastnext != $$op) { + # insert a 'goto' + my $h = {"seq" => seq($lastnext), "class" => class($lastnext), + "addr" => sprintf("%#x", $$lastnext)}; + print # $walkHandle + fmt_line($h, $op, $style{"terse"}[1], $level+1); + } + $lastnext = $op->next; + print # $walkHandle + concise_op($op, $level, $style{"terse"}[0]); +} + +sub tree { + my $op = shift; + my $level = shift; + my $style = $tree_decorations[$tree_style]; + my($space, $single, $kids, $kid, $nokid, $last, $lead, $size) = @$style; + my $name = concise_op($op, $level, $treefmt); + if (not $op->flags & OPf_KIDS) { + return $name . "\n"; + } + my @lines; + for (my $kid = $op->first; $$kid; $kid = $kid->sibling) { + push @lines, tree($kid, $level+1); + } + my $i; + for ($i = $#lines; substr($lines[$i], 0, 1) eq " "; $i--) { + $lines[$i] = $space . $lines[$i]; + } + if ($i > 0) { + $lines[$i] = $last . $lines[$i]; + while ($i-- > 1) { + if (substr($lines[$i], 0, 1) eq " ") { + $lines[$i] = $nokid . $lines[$i]; + } else { + $lines[$i] = $kid . $lines[$i]; + } + } + $lines[$i] = $kids . $lines[$i]; + } else { + $lines[0] = $single . $lines[0]; + } + return("$name$lead" . shift @lines, + map(" " x (length($name)+$size) . $_, @lines)); +} + +# *** Warning: fragile kludge ahead *** +# Because the B::* modules run in the same interpreter as the code +# they're compiling, their presence tends to distort the view we have of +# the code we're looking at. In particular, perl gives sequence numbers +# to COPs. If the program we're looking at were run on its own, this +# would start at 1. Because all of B::Concise and all the modules it +# uses are compiled first, though, by the time we get to the user's +# program the sequence number is already pretty high, which could be +# distracting if you're trying to tell OPs apart. Therefore we'd like to +# subtract an offset from all the sequence numbers we display, to +# restore the simpler view of the world. The trick is to know what that +# offset will be, when we're still compiling B::Concise! If we +# hardcoded a value, it would have to change every time B::Concise or +# other modules we use do. To help a little, what we do here is compile +# a little code at the end of the module, and compute the base sequence +# number for the user's program as being a small offset later, so all we +# have to worry about are changes in the offset. + +# [For 5.8.x and earlier perl is generating sequence numbers for all ops, +# and using them to reference labels] + + +# When you say "perl -MO=Concise -e '$a'", the output should look like: + +# 4 <@> leave[t1] vKP/REFC ->(end) +# 1 <0> enter ->2 + #^ smallest OP sequence number should be 1 +# 2 <;> nextstate(main 1 -e:1) v ->3 + # ^ smallest COP sequence number should be 1 +# - <1> ex-rv2sv vK/1 ->4 +# 3 <$> gvsv(*a) s ->4 + +# If the second of the marked numbers there isn't 1, it means you need +# to update the corresponding magic number in the next line. +# Remember, this needs to stay the last things in the module. + +# Why is this different for MacOS? Does it matter? +my $cop_seq_mnum = $^O eq 'MacOS' ? 12 : 11; +$cop_seq_base = svref_2object(eval 'sub{0;}')->START->cop_seq + $cop_seq_mnum; + +1; + +__END__ + +=head1 NAME + +B::Concise - Walk Perl syntax tree, printing concise info about ops + +=head1 SYNOPSIS + + perl -MO=Concise[,OPTIONS] foo.pl + + use B::Concise qw(set_style add_callback); + +=head1 DESCRIPTION + +This compiler backend prints the internal OPs of a Perl program's syntax +tree in one of several space-efficient text formats suitable for debugging +the inner workings of perl or other compiler backends. It can print OPs in +the order they appear in the OP tree, in the order they will execute, or +in a text approximation to their tree structure, and the format of the +information displayed is customizable. Its function is similar to that of +perl's B<-Dx> debugging flag or the B<B::Terse> module, but it is more +sophisticated and flexible. + +=head1 EXAMPLE + +Here's an example of 2 outputs (aka 'renderings'), using the +-exec and -basic (i.e. default) formatting conventions on the same code +snippet. + + % perl -MO=Concise,-exec -e '$a = $b + 42' + 1 <0> enter + 2 <;> nextstate(main 1 -e:1) v + 3 <#> gvsv[*b] s + 4 <$> const[IV 42] s + * 5 <2> add[t3] sK/2 + 6 <#> gvsv[*a] s + 7 <2> sassign vKS/2 + 8 <@> leave[1 ref] vKP/REFC + +Each line corresponds to an opcode. The opcode marked with '*' is used +in a few examples below. + +The 1st column is the op's sequence number, starting at 1, and is +displayed in base 36 by default. This rendering is in -exec (i.e. +execution) order. + +The symbol between angle brackets indicates the op's type, for +example; <2> is a BINOP, <@> a LISTOP, and <#> is a PADOP, which is +used in threaded perls. (see L</"OP class abbreviations">). + +The opname, as in B<'add[t1]'>, which may be followed by op-specific +information in parentheses or brackets (ex B<'[t1]'>). + +The op-flags (ex B<'sK/2'>) follow, and are described in (L</"OP flags +abbreviations">). + + % perl -MO=Concise -e '$a = $b + 42' + 8 <@> leave[1 ref] vKP/REFC ->(end) + 1 <0> enter ->2 + 2 <;> nextstate(main 1 -e:1) v ->3 + 7 <2> sassign vKS/2 ->8 + * 5 <2> add[t1] sK/2 ->6 + - <1> ex-rv2sv sK/1 ->4 + 3 <$> gvsv(*b) s ->4 + 4 <$> const(IV 42) s ->5 + - <1> ex-rv2sv sKRM*/1 ->7 + 6 <$> gvsv(*a) s ->7 + +The default rendering is top-down, so they're not in execution order. +This form reflects the way the stack is used to parse and evaluate +expressions; the add operates on the two terms below it in the tree. + +Nullops appear as C<ex-opname>, where I<opname> is an op that has been +optimized away by perl. They're displayed with a sequence-number of +'-', because they are not executed (they don't appear in previous +example), they're printed here because they reflect the parse. + +The arrow points to the sequence number of the next op; they're not +displayed in -exec mode, for obvious reasons. + +Note that because this rendering was done on a non-threaded perl, the +PADOPs in the previous examples are now SVOPs, and some (but not all) +of the square brackets have been replaced by round ones. This is a +subtle feature to provide some visual distinction between renderings +on threaded and un-threaded perls. + + +=head1 OPTIONS + +Arguments that don't start with a hyphen are taken to be the names of +subroutines to print the OPs of; if no such functions are specified, +the main body of the program (outside any subroutines, and not +including use'd or require'd files) is rendered. Passing C<BEGIN>, +C<CHECK>, C<INIT>, or C<END> will cause all of the corresponding +special blocks to be printed. + +Options affect how things are rendered (ie printed). They're presented +here by their visual effect, 1st being strongest. They're grouped +according to how they interrelate; within each group the options are +mutually exclusive (unless otherwise stated). + +=head2 Options for Opcode Ordering + +These options control the 'vertical display' of opcodes. The display +'order' is also called 'mode' elsewhere in this document. + +=over 4 + +=item B<-basic> + +Print OPs in the order they appear in the OP tree (a preorder +traversal, starting at the root). The indentation of each OP shows its +level in the tree, and the '->' at the end of the line indicates the +next opcode in execution order. This mode is the default, so the flag +is included simply for completeness. + +=item B<-exec> + +Print OPs in the order they would normally execute (for the majority +of constructs this is a postorder traversal of the tree, ending at the +root). In most cases the OP that usually follows a given OP will +appear directly below it; alternate paths are shown by indentation. In +cases like loops when control jumps out of a linear path, a 'goto' +line is generated. + +=item B<-tree> + +Print OPs in a text approximation of a tree, with the root of the tree +at the left and 'left-to-right' order of children transformed into +'top-to-bottom'. Because this mode grows both to the right and down, +it isn't suitable for large programs (unless you have a very wide +terminal). + +=back + +=head2 Options for Line-Style + +These options select the line-style (or just style) used to render +each opcode, and dictates what info is actually printed into each line. + +=over 4 + +=item B<-concise> + +Use the author's favorite set of formatting conventions. This is the +default, of course. + +=item B<-terse> + +Use formatting conventions that emulate the output of B<B::Terse>. The +basic mode is almost indistinguishable from the real B<B::Terse>, and the +exec mode looks very similar, but is in a more logical order and lacks +curly brackets. B<B::Terse> doesn't have a tree mode, so the tree mode +is only vaguely reminiscent of B<B::Terse>. + +=item B<-linenoise> + +Use formatting conventions in which the name of each OP, rather than being +written out in full, is represented by a one- or two-character abbreviation. +This is mainly a joke. + +=item B<-debug> + +Use formatting conventions reminiscent of B<B::Debug>; these aren't +very concise at all. + +=item B<-env> + +Use formatting conventions read from the environment variables +C<B_CONCISE_FORMAT>, C<B_CONCISE_GOTO_FORMAT>, and C<B_CONCISE_TREE_FORMAT>. + +=back + +=head2 Options for tree-specific formatting + +=over 4 + +=item B<-compact> + +Use a tree format in which the minimum amount of space is used for the +lines connecting nodes (one character in most cases). This squeezes out +a few precious columns of screen real estate. + +=item B<-loose> + +Use a tree format that uses longer edges to separate OP nodes. This format +tends to look better than the compact one, especially in ASCII, and is +the default. + +=item B<-vt> + +Use tree connecting characters drawn from the VT100 line-drawing set. +This looks better if your terminal supports it. + +=item B<-ascii> + +Draw the tree with standard ASCII characters like C<+> and C<|>. These don't +look as clean as the VT100 characters, but they'll work with almost any +terminal (or the horizontal scrolling mode of less(1)) and are suitable +for text documentation or email. This is the default. + +=back + +These are pairwise exclusive, i.e. compact or loose, vt or ascii. + +=head2 Options controlling sequence numbering + +=over 4 + +=item B<-base>I<n> + +Print OP sequence numbers in base I<n>. If I<n> is greater than 10, the +digit for 11 will be 'a', and so on. If I<n> is greater than 36, the digit +for 37 will be 'A', and so on until 62. Values greater than 62 are not +currently supported. The default is 36. + +=item B<-bigendian> + +Print sequence numbers with the most significant digit first. This is the +usual convention for Arabic numerals, and the default. + +=item B<-littleendian> + +Print seqence numbers with the least significant digit first. This is +obviously mutually exclusive with bigendian. + +=back + +=head2 Other options + +These are pairwise exclusive. + +=over 4 + +=item B<-main> + +Include the main program in the output, even if subroutines were also +specified. This rendering is normally suppressed when a subroutine +name or reference is given. + +=item B<-nomain> + +This restores the default behavior after you've changed it with '-main' +(it's not normally needed). If no subroutine name/ref is given, main is +rendered, regardless of this flag. + +=item B<-nobanner> + +Renderings usually include a banner line identifying the function name +or stringified subref. This suppresses the printing of the banner. + +TBC: Remove the stringified coderef; while it provides a 'cookie' for +each function rendered, the cookies used should be 1,2,3.. not a +random hex-address. It also complicates string comparison of two +different trees. + +=item B<-banner> + +restores default banner behavior. + +=item B<-banneris> => subref + +TBC: a hookpoint (and an option to set it) for a user-supplied +function to produce a banner appropriate for users needs. It's not +ideal, because the rendering-state variables, which are a natural +candidate for use in concise.t, are unavailable to the user. + +=back + +=head2 Option Stickiness + +If you invoke Concise more than once in a program, you should know that +the options are 'sticky'. This means that the options you provide in +the first call will be remembered for the 2nd call, unless you +re-specify or change them. + +=head1 ABBREVIATIONS + +The concise style uses symbols to convey maximum info with minimal +clutter (like hex addresses). With just a little practice, you can +start to see the flowers, not just the branches, in the trees. + +=head2 OP class abbreviations + +These symbols appear before the op-name, and indicate the +B:: namespace that represents the ops in your Perl code. + + 0 OP (aka BASEOP) An OP with no children + 1 UNOP An OP with one child + 2 BINOP An OP with two children + | LOGOP A control branch OP + @ LISTOP An OP that could have lots of children + / PMOP An OP with a regular expression + $ SVOP An OP with an SV + " PVOP An OP with a string + { LOOP An OP that holds pointers for a loop + ; COP An OP that marks the start of a statement + # PADOP An OP with a GV on the pad + +=head2 OP flags abbreviations + +OP flags are either public or private. The public flags alter the +behavior of each opcode in consistent ways, and are represented by 0 +or more single characters. + + v OPf_WANT_VOID Want nothing (void context) + s OPf_WANT_SCALAR Want single value (scalar context) + l OPf_WANT_LIST Want list of any length (list context) + Want is unknown + K OPf_KIDS There is a firstborn child. + P OPf_PARENS This operator was parenthesized. + (Or block needs explicit scope entry.) + R OPf_REF Certified reference. + (Return container, not containee). + M OPf_MOD Will modify (lvalue). + S OPf_STACKED Some arg is arriving on the stack. + * OPf_SPECIAL Do something weird for this op (see op.h) + +Private flags, if any are set for an opcode, are displayed after a '/' + + 8 <@> leave[1 ref] vKP/REFC ->(end) + 7 <2> sassign vKS/2 ->8 + +They're opcode specific, and occur less often than the public ones, so +they're represented by short mnemonics instead of single-chars; see +F<op.h> for gory details, or try this quick 2-liner: + + $> perl -MB::Concise -de 1 + DB<1> |x \%B::Concise::priv + +=head1 FORMATTING SPECIFICATIONS + +For each line-style ('concise', 'terse', 'linenoise', etc.) there are +3 format-specs which control how OPs are rendered. + +The first is the 'default' format, which is used in both basic and exec +modes to print all opcodes. The 2nd, goto-format, is used in exec +mode when branches are encountered. They're not real opcodes, and are +inserted to look like a closing curly brace. The tree-format is tree +specific. + +When a line is rendered, the correct format-spec is copied and scanned +for the following items; data is substituted in, and other +manipulations like basic indenting are done, for each opcode rendered. + +There are 3 kinds of items that may be populated; special patterns, +#vars, and literal text, which is copied verbatim. (Yes, it's a set +of s///g steps.) + +=head2 Special Patterns + +These items are the primitives used to perform indenting, and to +select text from amongst alternatives. + +=over 4 + +=item B<(x(>I<exec_text>B<;>I<basic_text>B<)x)> + +Generates I<exec_text> in exec mode, or I<basic_text> in basic mode. + +=item B<(*(>I<text>B<)*)> + +Generates one copy of I<text> for each indentation level. + +=item B<(*(>I<text1>B<;>I<text2>B<)*)> + +Generates one fewer copies of I<text1> than the indentation level, followed +by one copy of I<text2> if the indentation level is more than 0. + +=item B<(?(>I<text1>B<#>I<var>I<Text2>B<)?)> + +If the value of I<var> is true (not empty or zero), generates the +value of I<var> surrounded by I<text1> and I<Text2>, otherwise +nothing. + +=item B<~> + +Any number of tildes and surrounding whitespace will be collapsed to +a single space. + +=back + +=head2 # Variables + +These #vars represent opcode properties that you may want as part of +your rendering. The '#' is intended as a private sigil; a #var's +value is interpolated into the style-line, much like "read $this". + +These vars take 3 forms: + +=over 4 + +=item B<#>I<var> + +A property named 'var' is assumed to exist for the opcodes, and is +interpolated into the rendering. + +=item B<#>I<var>I<N> + +Generates the value of I<var>, left justified to fill I<N> spaces. +Note that this means while you can have properties 'foo' and 'foo2', +you cannot render 'foo2', but you could with 'foo2a'. You would be +wise not to rely on this behavior going forward ;-) + +=item B<#>I<Var> + +This ucfirst form of #var generates a tag-value form of itself for +display; it converts '#Var' into a 'Var => #var' style, which is then +handled as described above. (Imp-note: #Vars cannot be used for +conditional-fills, because the => #var transform is done after the check +for #Var's value). + +=back + +The following variables are 'defined' by B::Concise; when they are +used in a style, their respective values are plugged into the +rendering of each opcode. + +Only some of these are used by the standard styles, the others are +provided for you to delve into optree mechanics, should you wish to +add a new style (see L</add_style> below) that uses them. You can +also add new ones using L</add_callback>. + +=over 4 + +=item B<#addr> + +The address of the OP, in hexadecimal. + +=item B<#arg> + +The OP-specific information of the OP (such as the SV for an SVOP, the +non-local exit pointers for a LOOP, etc.) enclosed in parentheses. + +=item B<#class> + +The B-determined class of the OP, in all caps. + +=item B<#classsym> + +A single symbol abbreviating the class of the OP. + +=item B<#coplabel> + +The label of the statement or block the OP is the start of, if any. + +=item B<#exname> + +The name of the OP, or 'ex-foo' if the OP is a null that used to be a foo. + +=item B<#extarg> + +The target of the OP, or nothing for a nulled OP. + +=item B<#firstaddr> + +The address of the OP's first child, in hexadecimal. + +=item B<#flags> + +The OP's flags, abbreviated as a series of symbols. + +=item B<#flagval> + +The numeric value of the OP's flags. + +=item B<#hyphseq> + +The sequence number of the OP, or a hyphen if it doesn't have one. + +=item B<#label> + +'NEXT', 'LAST', or 'REDO' if the OP is a target of one of those in exec +mode, or empty otherwise. + +=item B<#lastaddr> + +The address of the OP's last child, in hexadecimal. + +=item B<#name> + +The OP's name. + +=item B<#NAME> + +The OP's name, in all caps. + +=item B<#next> + +The sequence number of the OP's next OP. + +=item B<#nextaddr> + +The address of the OP's next OP, in hexadecimal. + +=item B<#noise> + +A one- or two-character abbreviation for the OP's name. + +=item B<#private> + +The OP's private flags, rendered with abbreviated names if possible. + +=item B<#privval> + +The numeric value of the OP's private flags. + +=item B<#seq> + +The sequence number of the OP. Note that this is a sequence number +generated by B::Concise. + +=item B<#seqnum> + +5.8.x and earlier only. 5.9 and later do not provide this. + +The real sequence number of the OP, as a regular number and not adjusted +to be relative to the start of the real program. (This will generally be +a fairly large number because all of B<B::Concise> is compiled before +your program is). + +=item B<#opt> + +Whether or not the op has been optimised by the peephole optimiser. + +Only available in 5.9 and later. + +=item B<#static> + +Whether or not the op is statically defined. This flag is used by the +B::C compiler backend and indicates that the op should not be freed. + +Only available in 5.9 and later. + +=item B<#sibaddr> + +The address of the OP's next youngest sibling, in hexadecimal. + +=item B<#svaddr> + +The address of the OP's SV, if it has an SV, in hexadecimal. + +=item B<#svclass> + +The class of the OP's SV, if it has one, in all caps (e.g., 'IV'). + +=item B<#svval> + +The value of the OP's SV, if it has one, in a short human-readable format. + +=item B<#targ> + +The numeric value of the OP's targ. + +=item B<#targarg> + +The name of the variable the OP's targ refers to, if any, otherwise the +letter t followed by the OP's targ in decimal. + +=item B<#targarglife> + +Same as B<#targarg>, but followed by the COP sequence numbers that delimit +the variable's lifetime (or 'end' for a variable in an open scope) for a +variable. + +=item B<#typenum> + +The numeric value of the OP's type, in decimal. + +=back + +=head1 Using B::Concise outside of the O framework + +The common (and original) usage of B::Concise was for command-line +renderings of simple code, as given in EXAMPLE. But you can also use +B<B::Concise> from your code, and call compile() directly, and +repeatedly. By doing so, you can avoid the compile-time only +operation of O.pm, and even use the debugger to step through +B::Concise::compile() itself. + +Once you're doing this, you may alter Concise output by adding new +rendering styles, and by optionally adding callback routines which +populate new variables, if such were referenced from those (just +added) styles. + +=head2 Example: Altering Concise Renderings + + use B::Concise qw(set_style add_callback); + add_style($yourStyleName => $defaultfmt, $gotofmt, $treefmt); + add_callback + ( sub { + my ($h, $op, $format, $level, $stylename) = @_; + $h->{variable} = some_func($op); + }); + $walker = B::Concise::compile(@options,@subnames,@subrefs); + $walker->(); + +=head2 set_style() + +B<set_style> accepts 3 arguments, and updates the three format-specs +comprising a line-style (basic-exec, goto, tree). It has one minor +drawback though; it doesn't register the style under a new name. This +can become an issue if you render more than once and switch styles. +Thus you may prefer to use add_style() and/or set_style_standard() +instead. + +=head2 set_style_standard($name) + +This restores one of the standard line-styles: C<terse>, C<concise>, +C<linenoise>, C<debug>, C<env>, into effect. It also accepts style +names previously defined with add_style(). + +=head2 add_style() + +This subroutine accepts a new style name and three style arguments as +above, and creates, registers, and selects the newly named style. It is +an error to re-add a style; call set_style_standard() to switch between +several styles. + +=head2 add_callback() + +If your newly minted styles refer to any new #variables, you'll need +to define a callback subroutine that will populate (or modify) those +variables. They are then available for use in the style you've +chosen. + +The callbacks are called for each opcode visited by Concise, in the +same order as they are added. Each subroutine is passed five +parameters. + + 1. A hashref, containing the variable names and values which are + populated into the report-line for the op + 2. the op, as a B<B::OP> object + 3. a reference to the format string + 4. the formatting (indent) level + 5. the selected stylename + +To define your own variables, simply add them to the hash, or change +existing values if you need to. The level and format are passed in as +references to scalars, but it is unlikely that they will need to be +changed or even used. + +=head2 Running B::Concise::compile() + +B<compile> accepts options as described above in L</OPTIONS>, and +arguments, which are either coderefs, or subroutine names. + +It constructs and returns a $treewalker coderef, which when invoked, +traverses, or walks, and renders the optrees of the given arguments to +STDOUT. You can reuse this, and can change the rendering style used +each time; thereafter the coderef renders in the new style. + +B<walk_output> lets you change the print destination from STDOUT to +another open filehandle, or into a string passed as a ref (unless +you've built perl with -Uuseperlio). + + my $walker = B::Concise::compile('-terse','aFuncName', \&aSubRef); # 1 + walk_output(\my $buf); + $walker->(); # 1 renders -terse + set_style_standard('concise'); # 2 + $walker->(); # 2 renders -concise + $walker->(@new); # 3 renders whatever + print "3 different renderings: terse, concise, and @new: $buf\n"; + +When $walker is called, it traverses the subroutines supplied when it +was created, and renders them using the current style. You can change +the style afterwards in several different ways: + + 1. call C<compile>, altering style or mode/order + 2. call C<set_style_standard> + 3. call $walker, passing @new options + +Passing new options to the $walker is the easiest way to change +amongst any pre-defined styles (the ones you add are automatically +recognized as options), and is the only way to alter rendering order +without calling compile again. Note however that rendering state is +still shared amongst multiple $walker objects, so they must still be +used in a coordinated manner. + +=head2 B::Concise::reset_sequence() + +This function (not exported) lets you reset the sequence numbers (note +that they're numbered arbitrarily, their goal being to be human +readable). Its purpose is mostly to support testing, i.e. to compare +the concise output from two identical anonymous subroutines (but +different instances). Without the reset, B::Concise, seeing that +they're separate optrees, generates different sequence numbers in +the output. + +=head2 Errors + +Errors in rendering (non-existent function-name, non-existent coderef) +are written to the STDOUT, or wherever you've set it via +walk_output(). + +Errors using the various *style* calls, and bad args to walk_output(), +result in die(). Use an eval if you wish to catch these errors and +continue processing. + +=head1 AUTHOR + +Stephen McCamant, E<lt>smcc@CSUA.Berkeley.EDUE<gt>. + +=cut |