[llvm-objcopy] [COFF] Clear the unwritten tail of coff_section::Header::Name

[llvm-complete.git] / utils / llvm-native-gxx

#!/usr/bin/perl
# Wrapper around LLVM tools to generate a native .o from llvm-gxx using an
# LLVM back-end (CBE by default).

# set up defaults.
$Verbose = 0;
$SaveTemps = 1;
$PreprocessOnly = 0;
$CompileDontLink = 0;
$Backend = 'cbe';
chomp ($ProgramName = `basename $0`);

sub boldprint {
        print "\e[1m", @_, "\e[0m";
}

# process command-line options.
# most of these are passed on to llvm-gxx.
$GCCOptions = "";
for ($i = 0; $i <= $#ARGV; ++$i) {      
        if ($ARGV[$i] =~ /-mllvm-backend=([a-z0-9]*)/) {
                $Backend = $1;
                if ($ProgramName =~ /llvm-native-gxx/) {
                        splice (@ARGV, $i, 1);
                        --$i;
                }
        } elsif ($ARGV[$i] eq "-E") {
                $PreprocessOnly = 1;
        } elsif ($ARGV[$i] eq "-c") {
                $GCCOptions .= " " . $ARGV[$i];
                $CompileDontLink = 1;
        } elsif ($ARGV[$i] eq "-v") {
                $GCCOptions .= " " . $ARGV[$i];
                $Verbose = 1;
        } elsif ($ARGV[$i] eq "-o") {
                $OutputFile = $ARGV[$i + 1];
        } elsif ($ARGV[$i] eq "-save-temps") {
                $GCCOptions .= " " . $ARGV[$i];
                $SaveTemps = 1;
        } elsif ($ARGV[$i] =~ /\.bc$/) {
                push (@BytecodeFiles, $ARGV[$i]);
        } elsif ($ARGV[$i] =~ /^-L/) {
                $GCCOptions .= " " . $ARGV[$i];
                push (@LibDirs, $ARGV[$i]);
        } elsif ($ARGV[$i] =~ /^-l/) {
                $GCCOptions .= " " . $ARGV[$i];
                push (@Libs, $ARGV[$i]);
        } elsif ($ARGV[$i] =~ /\.(c|cpp|cc|i|ii|C)$/) {
                $LastCFile = $ARGV[$i];
        }
}

sub GetDefaultOutputFileName {
        my $DefaultOutputFileBase;

        if ($ProgramName =~ /llvm-native-gxx/) {
                $DefaultOutputFileBase = $LastCFile;
        } elsif ($ProgramName =~ /native-build/) {
                $DefaultOutputFileBase = $BytecodeFiles[0];
        }

        my $def = $DefaultOutputFileBase;

        die "Can't figure out name of output file.\n"
                unless $DefaultOutputFileBase
                           && (($ProgramName !~ /native-build/)
                                   || $#BytecodeFiles == 0);

        print "Warning: defaulting output file name ",
                "based on '$DefaultOutputFileBase'\n" if $Verbose;

        if ($ProgramName =~ /llvm-native-gxx/) {
                $def =~ s/\.(c|cpp|cc|i|ii|C)$/.o/;
        } elsif ($ProgramName =~ /native-build/) {
                $def =~ s/\.bc$/.$Backend/;
                if ($CompileDontLink) {
                        $def .= ".o";
                }
        }

        return $def;
}

# run a command, optionally echoing, and quitting if it fails:
sub run {
        my $command = join(" ", @_);
        print "$command\n" if $Verbose;
        $command =~ s/\"/\\\"/g;
        system $command and die "$0: $command failed";
}

sub LinkBytecodeFilesIntoTemporary {
        my $FinalOutputFileName = shift @_;
        my @BytecodeFiles = @_;

        my $BCFiles = join (" ", @BytecodeFiles);
        my $LinkedBCFile;
        if ($SaveTemps) {
                $LinkedBCFile = "${FinalOutputFileName}.llvm.bc";
        } else {
                $LinkedBCFile = "/tmp/nativebuild-$$.llvm.bc";
        }
        run "llvm-link -o $LinkedBCFile $BCFiles";
        return $LinkedBCFile;
}

sub CompileBytecodeToNative {
        my ($BCFile, $Backend, $OutputFile) = @_;

        my $GeneratedCode;
        if ($Backend eq 'cbe') {
                if ($SaveTemps) {
                        $GeneratedCode = "${OutputFile}.c";
                } else {
                        $GeneratedCode = "/tmp/nativebuild-$$.c";
                }
                run "llc -march=c -f -o $GeneratedCode $BCFile";
        } elsif ($Backend eq 'llc') {
                if ($SaveTemps) {
                        $GeneratedCode = "${OutputFile}.s";
                } else {
                        $GeneratedCode = "/tmp/nativebuild-$$.s";
                }
                run "llc -f -o $GeneratedCode $BCFile";
        }
        my $LibDirs = join (" ", @LibDirs);
        my $Libs = join (" ", @Libs);
        run "gcc $GCCOptions $GeneratedCode -o $OutputFile $LibDirs $Libs";
        run "rm $BCFile $GeneratedCode"
                unless $SaveTemps;
}

sub CompileCToNative {
        my ($LLVMGCCCommand, $Backend, $OutputFile) = @_;
        run $LLVMGCCCommand;
        if ($PreprocessOnly) {
                return;
        }
        my $BCFile = "${OutputFile}.llvm.bc";
        if ($CompileDontLink) {
                run "mv ${OutputFile} $BCFile";
        } else { # gccld messes with the output file name
                run "mv ${OutputFile}.bc $BCFile";
        }
        my $GeneratedCode;
        if ($Backend eq 'cbe') {
                $GeneratedCode = "${OutputFile}.cbe.c";
                run "llc -march=c -f -o $GeneratedCode $BCFile";
        } elsif ($Backend eq 'llc') {
                $GeneratedCode = "${OutputFile}.llc.s";
                run "llc -f -o $GeneratedCode $BCFile";
        }
        my $NativeGCCOptions = "";
        if ($CompileDontLink) {
                $NativeGCCOptions = "-c";
        }
        run "gcc $NativeGCCOptions $GeneratedCode -o $OutputFile";
        run "rm ${OutputFile}.llvm.bc $GeneratedCode"
                unless $SaveTemps;
}

# guess the name of the output file, if -o was not specified.
$OutputFile = GetDefaultOutputFileName () unless $OutputFile;
print "Output file is $OutputFile\n" if $Verbose;
# do all the dirty work:
if ($ProgramName eq /native-build/) {
        my $LinkedBCFile = LinkBytecodeFilesIntoTemporary (@BytecodeFiles);
        CompileBytecodeToNative ($LinkedBCFile, $Backend, $OutputFile);
} elsif ($ProgramName =~ /llvm-native-gxx/) {
        # build the llvm-gxx command line.
        $LLVMGCCCommand = join (" ", ("llvm-g++", @ARGV));
        CompileCToNative ($LLVMGCCCommand, $Backend, $OutputFile);
}

# we're done.
exit 0;

__END__

=pod

=head1 NAME

llvm-native-gxx

=head1 SYNOPSIS

llvm-native-g++ [OPTIONS...] FILE

native-build [OPTIONS...] FILE

=head1 DESCRIPTION

llvm-native-g++ is a wrapper around the LLVM command-line tools which generates
a native object (.o) file by compiling FILE with llvm-g++, and then running 
an LLVM back-end (CBE by default) over the resulting bitcode, and then
compiling the resulting code to a native object file.

If called as "native-build", it compiles bitcode to native code, and takes
different options.

=head1 OPTIONS

llvm-native-g++ takes the same options as llvm-gcc. All options
except -mllvm-backend=... are passed on to llvm-g++.

=over 4

=item -mllvm-backend=BACKEND

Use BACKEND for native code generation. 

=item -v

Print command lines that llvm-native-g++ runs.

=item -o FILE

llvm-native-g++ tries to guess the name of the llvm-g++ output file by looking
for this option in the command line. If it can't find it, it finds the last C
or C++ source file named on the command line, and turns its suffix into .o. See
BUGS.

=item -save-temps

Save temporary files used by llvm-native-g++ (and llvm-g++, and g++).

=back

=head1 BUGS

llvm-native-g++ only handles the case where llvm-g++ compiles a single
file per invocation.  llvm-native-g++ has weak command-line argument
parsing and is a poor substitute for making g++/g++.c do this stuff.

This manual page does not adequately document native-build mode.

llvm-native-g++ is pretty gross because it represents the blind merging of two
other scripts that predated it. It could use some code clean-up.

=head1 SEE ALSO

g++(1)

=head1 AUTHOR

Brian R. Gaeke

=cut