llvm-project/llvm/docs/CommandGuide/opt.pod

=pod

=head1 NAME

opt - LLVM optimizer

=head1 SYNOPSIS

B<opt> [I<options>] [I<filename>]

=head1 DESCRIPTION

The B<opt> command is the modular LLVM optimizer.  It takes LLVM
bytecode as input, runs the specified optimizations on it, and then
outputs the optimized LLVM bytecode.

The optimizations available via B<opt> depend upon what libraries
were linked into it as well as any additional libraries that have
been loaded with the B<-load> option.  Use the B<-help> option to
determine what optimizations you can use.

If no filename is specified on the command line, B<opt> reads its
input from standard input.

If an output filename is not specified with the B<-o> option, B<opt>
writes its output to the standard output.

=head1 OPTIONS

=over

=item B<-f>

Force overwrite.  Normally, B<opt> will refuse to overwrite an
output file that already exists.  With this option, B<opt> will
overwrite the output file and replace it with new bytecode.

=item B<-help>

Print a summary of command line options.

=item B<-o> I<filename>

Specify the output filename.

=item B<-profile-info-file> I<filename>

Specify the name of the file loaded by the -profile-loader option.

=item B<-stats>

Print statistics.

=item B<-time-passes>

Record the amount of time needed for each pass and print it to standard
error.

=item B<-debug>

If this is a debug build, this option will enable debug printouts
from passes which use the I<DEBUG()> macro.  See the B<LLVM Programmer's
Manual>, section I<#DEBUG> for more information.

=item B<-load>=I<plugin>

Load the dynamic object I<plugin>.  This object should register new
optimization passes.  Once loaded, the object will add new command line
options to enable various optimizations.  To see the new complete list
of optimizations, use the B<-help> and B<-load> options together:

=over

B<opt -load>=I<plugin> B<-help>

=back

=item B<-p>

Print module after each transformation.

=back

=head1 EXIT STATUS

If B<opt> succeeds, it will exit with 0.  Otherwise, if an error
occurs, it will exit with a non-zero value.

=head1 SEE ALSO

L<analyze|analyze>

=head1 AUTHORS

Maintained by the LLVM Team (L<http://llvm.org>).

=cut