1#!/usr/bin/perl
2# Wrapper around LLVM tools to generate a native .o from llvm-gxx using an
3# LLVM back-end (CBE by default).
4
5# set up defaults.
6$Verbose = 0;
7$SaveTemps = 1;
8$PreprocessOnly = 0;
9$CompileDontLink = 0;
10$Backend = 'cbe';
11chomp ($ProgramName = `basename $0`);
12
13sub boldprint {
14	print "[1m", @_, "[0m";
15}
16
17# process command-line options.
18# most of these are passed on to llvm-gxx.
19$GCCOptions = "";
20for ($i = 0; $i <= $#ARGV; ++$i) {	
21	if ($ARGV[$i] =~ /-mllvm-backend=([a-z0-9]*)/) {
22		$Backend = $1;
23		if ($ProgramName =~ /llvm-native-gxx/) {
24			splice (@ARGV, $i, 1);
25			--$i;
26		}
27	} elsif ($ARGV[$i] eq "-E") {
28		$PreprocessOnly = 1;
29	} elsif ($ARGV[$i] eq "-c") {
30		$GCCOptions .= " " . $ARGV[$i];
31		$CompileDontLink = 1;
32	} elsif ($ARGV[$i] eq "-v") {
33		$GCCOptions .= " " . $ARGV[$i];
34		$Verbose = 1;
35	} elsif ($ARGV[$i] eq "-o") {
36		$OutputFile = $ARGV[$i + 1];
37	} elsif ($ARGV[$i] eq "-save-temps") {
38		$GCCOptions .= " " . $ARGV[$i];
39		$SaveTemps = 1;
40	} elsif ($ARGV[$i] =~ /\.bc$/) {
41		push (@BytecodeFiles, $ARGV[$i]);
42	} elsif ($ARGV[$i] =~ /^-L/) {
43		$GCCOptions .= " " . $ARGV[$i];
44		push (@LibDirs, $ARGV[$i]);
45	} elsif ($ARGV[$i] =~ /^-l/) {
46		$GCCOptions .= " " . $ARGV[$i];
47		push (@Libs, $ARGV[$i]);
48	} elsif ($ARGV[$i] =~ /\.(c|cpp|cc|i|ii|C)$/) {
49		$LastCFile = $ARGV[$i];
50	}
51}
52
53sub GetDefaultOutputFileName {
54	my $DefaultOutputFileBase;
55
56	if ($ProgramName =~ /llvm-native-gxx/) {
57		$DefaultOutputFileBase = $LastCFile;
58	} elsif ($ProgramName =~ /native-build/) {
59		$DefaultOutputFileBase = $BytecodeFiles[0];
60	}
61
62	my $def = $DefaultOutputFileBase;
63
64	die "Can't figure out name of output file.\n"
65		unless $DefaultOutputFileBase
66			   && (($ProgramName !~ /native-build/)
67				   || $#BytecodeFiles == 0);
68
69	print "Warning: defaulting output file name ",
70		"based on '$DefaultOutputFileBase'\n" if $Verbose;
71
72	if ($ProgramName =~ /llvm-native-gxx/) {
73		$def =~ s/\.(c|cpp|cc|i|ii|C)$/.o/;
74	} elsif ($ProgramName =~ /native-build/) {
75		$def =~ s/\.bc$/.$Backend/;
76		if ($CompileDontLink) {
77			$def .= ".o";
78		}
79	}
80
81	return $def;
82}
83
84# run a command, optionally echoing, and quitting if it fails:
85sub run {
86	my $command = join(" ", @_);
87	print "$command\n" if $Verbose;
88	$command =~ s/\"/\\\"/g;
89	system $command and die "$0: $command failed";
90}
91
92sub LinkBytecodeFilesIntoTemporary {
93	my $FinalOutputFileName = shift @_;
94	my @BytecodeFiles = @_;
95
96	my $BCFiles = join (" ", @BytecodeFiles);
97	my $LinkedBCFile;
98	if ($SaveTemps) {
99		$LinkedBCFile = "${FinalOutputFileName}.llvm.bc";
100	} else {
101		$LinkedBCFile = "/tmp/nativebuild-$$.llvm.bc";
102	}
103	run "llvm-link -o $LinkedBCFile $BCFiles";
104	return $LinkedBCFile;
105}
106
107sub CompileBytecodeToNative {
108	my ($BCFile, $Backend, $OutputFile) = @_;
109
110	my $GeneratedCode;
111	if ($Backend eq 'cbe') {
112		if ($SaveTemps) {
113			$GeneratedCode = "${OutputFile}.c";
114		} else {
115			$GeneratedCode = "/tmp/nativebuild-$$.c";
116		}
117		run "llc -march=c -f -o $GeneratedCode $BCFile";
118	} elsif ($Backend eq 'llc') {
119		if ($SaveTemps) {
120			$GeneratedCode = "${OutputFile}.s";
121		} else {
122			$GeneratedCode = "/tmp/nativebuild-$$.s";
123		}
124		run "llc -f -o $GeneratedCode $BCFile";
125	}
126	my $LibDirs = join (" ", @LibDirs);
127	my $Libs = join (" ", @Libs);
128	run "gcc $GCCOptions $GeneratedCode -o $OutputFile $LibDirs $Libs";
129	run "rm $BCFile $GeneratedCode"
130		unless $SaveTemps;
131}
132
133sub CompileCToNative {
134	my ($LLVMGCCCommand, $Backend, $OutputFile) = @_;
135	run $LLVMGCCCommand;
136	if ($PreprocessOnly) {
137		return;
138	}
139	my $BCFile = "${OutputFile}.llvm.bc";
140	if ($CompileDontLink) {
141		run "mv ${OutputFile} $BCFile";
142	} else { # gccld messes with the output file name
143		run "mv ${OutputFile}.bc $BCFile";
144	}
145	my $GeneratedCode;
146	if ($Backend eq 'cbe') {
147		$GeneratedCode = "${OutputFile}.cbe.c";
148		run "llc -march=c -f -o $GeneratedCode $BCFile";
149	} elsif ($Backend eq 'llc') {
150		$GeneratedCode = "${OutputFile}.llc.s";
151		run "llc -f -o $GeneratedCode $BCFile";
152	}
153	my $NativeGCCOptions = "";
154	if ($CompileDontLink) {
155		$NativeGCCOptions = "-c";
156	}
157	run "gcc $NativeGCCOptions $GeneratedCode -o $OutputFile";
158	run "rm ${OutputFile}.llvm.bc $GeneratedCode"
159		unless $SaveTemps;
160}
161
162# guess the name of the output file, if -o was not specified.
163$OutputFile = GetDefaultOutputFileName () unless $OutputFile;
164print "Output file is $OutputFile\n" if $Verbose;
165# do all the dirty work:
166if ($ProgramName eq /native-build/) {
167	my $LinkedBCFile = LinkBytecodeFilesIntoTemporary (@BytecodeFiles);
168	CompileBytecodeToNative ($LinkedBCFile, $Backend, $OutputFile);
169} elsif ($ProgramName =~ /llvm-native-gxx/) {
170	# build the llvm-gxx command line.
171	$LLVMGCCCommand = join (" ", ("llvm-g++", @ARGV));
172	CompileCToNative ($LLVMGCCCommand, $Backend, $OutputFile);
173}
174
175# we're done.
176exit 0;
177
178__END__
179
180=pod
181
182=head1 NAME
183
184llvm-native-gxx
185
186=head1 SYNOPSIS
187
188llvm-native-g++ [OPTIONS...] FILE
189
190native-build [OPTIONS...] FILE
191
192=head1 DESCRIPTION
193
194llvm-native-g++ is a wrapper around the LLVM command-line tools which generates
195a native object (.o) file by compiling FILE with llvm-g++, and then running 
196an LLVM back-end (CBE by default) over the resulting bitcode, and then
197compiling the resulting code to a native object file.
198
199If called as "native-build", it compiles bitcode to native code, and takes
200different options.
201
202=head1 OPTIONS
203
204llvm-native-g++ takes the same options as llvm-gcc. All options
205except -mllvm-backend=... are passed on to llvm-g++.
206
207=over 4
208
209=item -mllvm-backend=BACKEND
210
211Use BACKEND for native code generation. 
212
213=item -v
214
215Print command lines that llvm-native-g++ runs.
216
217=item -o FILE
218
219llvm-native-g++ tries to guess the name of the llvm-g++ output file by looking
220for this option in the command line. If it can't find it, it finds the last C
221or C++ source file named on the command line, and turns its suffix into .o. See
222BUGS.
223
224=item -save-temps
225
226Save temporary files used by llvm-native-g++ (and llvm-g++, and g++).
227
228=back
229
230=head1 BUGS
231
232llvm-native-g++ only handles the case where llvm-g++ compiles a single
233file per invocation.  llvm-native-g++ has weak command-line argument
234parsing and is a poor substitute for making g++/g++.c do this stuff.
235
236This manual page does not adequately document native-build mode.
237
238llvm-native-g++ is pretty gross because it represents the blind merging of two
239other scripts that predated it. It could use some code clean-up.
240
241=head1 SEE ALSO
242
243g++(1)
244
245=head1 AUTHOR
246
247Brian R. Gaeke
248
249=cut
250