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comparison utils/codegen-diff @ 171:66f3bfe93da9

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git version 2c4ca6832fa6b306ee6a7010bfb80a3f2596f824
author Shinji KONO <kono@ie.u-ryukyu.ac.jp>
date Mon, 25 May 2020 11:07:02 +0900
parents 95c75e76d11b
children
comparison
equal deleted inserted replaced
150:1d019706d866 171:66f3bfe93da9
1 #!/usr/bin/perl
2
3 use Getopt::Std;
4 $DEBUG = 0;
5
6 sub parse_objdump_file {
7 my ($filename) = @_;
8 my @result;
9 open (INPUT, $filename) or die "$filename: $!\n";
10 print "opened objdump output file $filename\n" if $DEBUG;
11 while (<INPUT>) {
12 if (/\s*([0-9a-f]*):\t(([0-9a-f]{2} )+) *\t(.*)$/) {
13 my ($addr, $bytes, $instr) = ($1, $2, $4);
14 $addr = "0x" . $addr;
15 $bytes =~ s/\s*(.*\S)\s*/$1/; # trim any remaining whitespace
16 $instr =~ s/\s*(.*\S)\s*/$1/;
17 push (@result, {'addr' => $addr, 'bytes' => $bytes, 'instr' => $instr});
18 print "addr=$addr bytes='$bytes' instr='$instr'\n" if $DEBUG;
19 }
20 }
21 close INPUT;
22 return @result;
23 }
24
25 sub parse_gdb_file {
26 my ($filename) = @_;
27 my @result;
28 my $got_addr;
29 open (INPUT, $filename) or die "$filename: $!\n";
30 print "opened gdb output file $filename\n" if $DEBUG;
31 while (<INPUT>) {
32 if (/^(0x[0-9a-f]*):\t([^\t]*)\t[^:]*:\t((0x[0-9a-f]{2}\s*)+)\s*$/) {
33 my ($addr, $bytes, $instr) = ($1, $3, $2);
34 $bytes =~ s/0x//g;
35 $bytes =~ s/\s+/ /g; # regularize whitespace
36 $bytes =~ s/\s*(.*\S)\s*/$1/; # trim any remaining whitespace
37 $instr =~ s/\s*(.*\S)\s*/$1/;
38 push (@result, {'addr' => $addr, 'bytes' => $bytes, 'instr' => $instr});
39 print "addr=$addr bytes='$bytes' instr='$instr'\n" if $DEBUG;
40 } elsif (/^(0x[0-9a-f]*):\t$/) { # deal with gdb's line breaker
41 $got_addr = $1;
42 } elsif ($got_addr && /^ ([^\t]*)\t[^:]*:\t((0x[0-9a-f]{2}\s*)+)\s*$/) {
43 my ($addr, $bytes, $instr) = ($got_addr, $2, $1);
44 $bytes =~ s/0x//g;
45 $bytes =~ s/\s+/ /g; # regularize whitespace
46 $bytes =~ s/\s*(.*\S)\s*/$1/; # trim any remaining whitespace
47 $instr =~ s/\s*(.*\S)\s*/$1/;
48 push (@result, {'addr' => $addr, 'bytes' => $bytes, 'instr' => $instr});
49 print "addr=$addr bytes='$bytes' instr='$instr'\n" if $DEBUG;
50 undef $got_addr;
51 }
52 }
53 close INPUT;
54 return @result;
55 }
56
57 sub binary_diffs {
58 my ($objdump_file, $gdb_file) = @_;
59 my @file1 = parse_objdump_file ($objdump_file);
60 my @file2 = parse_gdb_file ($gdb_file);
61 my $lastrecord = ($#file1 >= $#file2) ? ($#file1) : ($#file2);
62 for (my $i = 0; $i <= $lastrecord; ++$i) {
63 my $d1 = $file1[$i];
64 my $d2 = $file2[$i];
65 if ($d1->{'bytes'} ne $d2->{'bytes'}) {
66 next if (($d1->{'instr'} eq $d2->{'instr'}) && $opt_d);
67 printf "0x%08x:\t%30s \t%s\n", 0+$d1->{'addr'}, $d1->{'bytes'}, $d1->{'instr'};
68 printf "0x%08x:\t%30s \t%s\n\n", 0+$d2->{'addr'}, $d2->{'bytes'}, $d2->{'instr'};
69 }
70 }
71 }
72
73 &getopts('d');
74 $objdump_file = $ARGV[0];
75 $gdb_file = $ARGV[1];
76 binary_diffs ($objdump_file, $gdb_file);
77 exit (0);
78 __END__
79 =pod
80
81 =head1 NAME
82
83 codegen-diff
84
85 =head1 SYNOPSIS
86
87 codegen-diff [-d] I<OBJDUMP-OUTPUT-FILE> I<GDB-DISASSEMBLY-FILE>
88
89 =head1 DESCRIPTION
90
91 B<codegen-diff> is a program that tries to show you the differences
92 between the code that B<llc> generated and the code that B<lli> generated.
93
94 The way you use it is as follows: first, you create I<OBJDUMP-OUTPUT-FILE>
95 by running B<objdump> on the B<llc> compiled and linked binary. You need to
96 trim down the result so it contains only the function of interest.
97
98 Second, you create I<GDB-DISASSEMBLY-FILE> by running B<gdb>, with my patch
99 to print out hex bytes in the B<disassemble> command output, on
100 B<lli>. Set a breakpoint in C<Emitter::finishFunction()> and wait until
101 the function you want is compiled. Then use the B<disassemble> command
102 to print out the assembly dump of the function B<lli> just compiled.
103 (Use C<lli -debug> to find out where the function starts and ends in memory.)
104 It's easiest to save this output by using B<script>.
105
106 Finally, you run B<codegen-diff>, as indicated in the Synopsis section of
107 this manpage. It will print out a two-line stanza for each mismatched
108 instruction, with the B<llc> version first, and the B<lli> version second.
109
110 =head1 OPTIONS
111
112 =over 4
113
114 =item -d
115
116 Don't show instructions where the bytes are different but they
117 disassemble to the same thing. This puts a lot of trust in the
118 disassembler, but it might help you highlight the more egregious cases
119 of misassembly.
120
121 =back
122
123 =head1 AUTHOR
124
125 B<codegen-diff> was written by Brian Gaeke.
126
127 =head1 SEE ALSO
128
129 L<gdb(1)>, L<objdump(1)>, L<script(1)>.
130
131 You will need my B<gdb> patch:
132
133 http://llvm.cs.uiuc.edu/~gaeke/gdb-disassembly-print-bytes.patch
134
135 =cut