NAME

B::Bytecode - Perl compiler's bytecode backend

SYNOPSIS

perl -MO=Bytecode[,-H][,-oscript.plc] script.pl

DESCRIPTION

Compiles a Perl script into a bytecode format that could be loaded later by the ByteLoader module and executed as a regular Perl script.

EXAMPLE

    $ perl -MO=Bytecode,-H,-ohi -e 'print "hi!\n"'
    $ perl hi
    hi!

OPTIONS

-H

Prepend a use ByteLoader VERSION; line to the produced bytecode.

-b

Save all the BEGIN blocks. Normally only BEGIN blocks that require other files (ex. use Foo;) are saved.

-k

Keep the syntax tree - it is stripped by default.

-ooutfile

Put the bytecode in <outfile> instead of dumping it to STDOUT.

-s

Scan the script for # line .. directives and for <goto LABEL> expressions. When gotos are found keep the syntax tree.

-S

Output assembler source rather than piping it through the assembler and outputting bytecode. Without -q the assembler source is commented.

-q

Be quiet.

-v

Be verbose.

-Do

OPs, prints each OP as it's processed

-DM

Set debugging flag for more verbose STDERR output. Verbose debugging options are crucial, because we have no interactive debugger at the early CHECK step, where the compilation happens.

M for Magic and Matches.

-DG

Debug GV's

-DA

Set developer Assertions, to help find possible obj-indices out of range.

KNOWN BUGS

• BEGIN { goto A: while 1; A: } won't even compile.
• ?...? and reset do not work as expected.
• variables in (?{ ... }) constructs are not properly scoped.
• Scripts that use source filters will fail miserably.
• Special GV's fail.

NOTICE

There are also undocumented bugs and options.

THIS CODE IS HIGHLY EXPERIMENTAL. USE AT YOUR OWN RISK.

AUTHORS

Originally written by Malcolm Beattie <mbeattie@sable.ox.ac.uk> and modified by Benjamin Stuhl <sho_pi@hotmail.com>.

Rewritten by Enache Adrian <enache@rdslink.ro>, 2003 a.d.

Enhanced by Reini Urban <rurban@cpan.org>, 2008