File Coverage

blib/lib/B/Bblock.pm

Criterion	Covered	Total	%
statement	9	99	9.0
branch	0	34	0.0
condition	0	21	0.0
subroutine	3	17	17.6
pod	1	6	16.6
total	13	177	7.3

# Maintained now in B::C by Reini Urban
package B::Bblock;

our $VERSION = '1.04';

use Exporter ();
@ISA       = "Exporter";
our @EXPORT_OK = qw(find_leaders);

use B qw(peekop walkoptree walkoptree_exec
  main_root main_start svref_2object
  OPf_SPECIAL OPf_STACKED );

use strict;

my $bblock;
my @bblock_ends;

sub mark_leader {
  my $op = shift;
  if ($$op) {
    $bblock->{$$op} = $op;
  }
}

sub remove_sortblock {
  foreach ( keys %$bblock ) {
    my $leader = $$bblock{$_};
    delete $$bblock{$_} if ( $leader == 0 );
  }
}

sub find_leaders {
  my ( $root, $start ) = @_;
  $bblock = {};
  mark_leader($start) if ( ref $start ne "B::NULL" );
  walkoptree( $root, "mark_if_leader" ) if ( ( ref $root ) ne "B::NULL" );
  remove_sortblock();
  return $bblock;
}

# Debugging
sub walk_bblocks {
  my ( $root, $start ) = @_;
  my ( $op, $lastop, $leader, $bb );
  $bblock = {};
  mark_leader($start);
  walkoptree( $root, "mark_if_leader" );
  my @leaders = values %$bblock;
  while ( $leader = shift @leaders ) {
    $lastop = $leader;
    $op     = $leader->next;
    while ( $$op && !exists( $bblock->{$$op} ) ) {
      $bblock->{$$op} = $leader;
      $lastop         = $op;
      $op             = $op->next;
    }
    push( @bblock_ends, [ $leader, $lastop ] );
  }
  foreach $bb (@bblock_ends) {
    ( $leader, $lastop ) = @$bb;
    printf "%s .. %s\n", peekop($leader), peekop($lastop);
    for ( $op = $leader ; $$op != $$lastop ; $op = $op->next ) {
      printf "    %s\n", peekop($op);
    }
    printf "    %s\n", peekop($lastop);
  }
}

sub walk_bblocks_obj {
  my $cvref = shift;
  my $cv    = svref_2object($cvref);
  walk_bblocks( $cv->ROOT, $cv->START );
}

sub B::OP::mark_if_leader { }

sub B::COP::mark_if_leader {
  my $op = shift;
  if ( $op->label ) {
    mark_leader($op);
  }
}

sub B::LOOP::mark_if_leader {
  my $op = shift;
  mark_leader( $op->next );
  mark_leader( $op->nextop );
  mark_leader( $op->redoop );
  mark_leader( $op->lastop->next );
}

sub B::LOGOP::mark_if_leader {
  my $op     = shift;
  my $opname = $op->name;
  mark_leader( $op->next );
  if ( $opname eq "entertry" ) {
    mark_leader( $op->other->next );
  }
  else {
    mark_leader( $op->other );
  }
}

sub B::LISTOP::mark_if_leader {
  my $op    = shift;
  my $first = $op->first;
  $first = $first->next while ( $first->name eq "null" );
  mark_leader( $op->first ) unless ( exists( $bblock->{$$first} ) );
  mark_leader( $op->next );
  if (  $op->name eq "sort"
    and $op->flags & OPf_SPECIAL
    and $op->flags & OPf_STACKED )
  {
    my $root   = $op->first->sibling->first;
    my $leader = $root->first;
    $bblock->{$$leader} = 0;
  }
}

sub B::PMOP::mark_if_leader {
  my $op = shift;
  if (  $op->type
    and $op->name ne "pushre"
    and ($] > 5.008005 or $op->name ne "substcont") )
  {
    #warn $op->name, $op->type if $] == 5.008004;
    my $replroot = $op->pmreplroot;
    if ($$replroot) {
      mark_leader( $replroot );
      mark_leader( $op->next );
      mark_leader( $op->pmreplstart );
    }
  }
}

# PMOP stuff omitted

sub compile {
  my @options = @_;
  my $have_B_Concise;
  B::clearsym();

  eval { require B::Concise; 1 } and $have_B_Concise = 1;
  B::Concise->import(qw(concise_cv concise_main set_style_standard))
      if $have_B_Concise;

  if ( @options and $have_B_Concise ) {
    return sub {
      my $objname;
      foreach $objname (@options) {
        $objname = "main::$objname" unless $objname =~ /::/;
        print "walk_bblocks $objname\n";
        eval "walk_bblocks_obj(\\&$objname)";
        die "walk_bblocks_obj(\\&$objname) failed: $@" if $@;
        print "-------\n";
        set_style_standard("terse");
        eval "concise_cv('exec', \\&$objname)";
        die "concise_cv('exec', \\&$objname) failed: $@" if $@;
      }
      }
  }
  else {
    return sub {
      walk_bblocks( main_root, main_start );
      print "-------\n";
      if ($have_B_Concise) {
        set_style_standard("terse");
        concise_main("exec");
      }
    };
  }
}

1;

__END__