3 # Note: You might need to install the Verilog::VCD package using CPAN..
7 use Verilog
::VCD
qw(parse_vcd list_sigs);
16 if ($ARGV[0] eq '-w') {
17 $opt_width = +$ARGV[1];
22 if ($ARGV[0] eq '-d') {
23 $opt_delay = +$ARGV[1];
33 print STDERR
"VCDCD - Value Change Dump Change Dumper\n";
35 print STDERR
"Usage: $0 [-w N] [-d N] gold.vcd gate.vcd\n";
37 print STDERR
" -w N\n";
38 print STDERR
" reserve N characters for bitmap in text output (default: auto)\n";
40 print STDERR
" -d N\n";
41 print STDERR
" allow for N timesteps delay between gate and gold (default: 0)\n";
43 print STDERR
"Compare a known-good (gold) vcd file with a second (gate) vcd file.\n";
44 print STDERR
"This is not very efficient -- so use with care on large vcd files.\n";
49 my $fn_gold = $ARGV[0];
50 my $fn_gate = $ARGV[1];
52 print "Finding common signals..\n";
53 my @gold_signals = list_sigs
($fn_gold);
54 my @gate_signals = list_sigs
($fn_gate);
56 my %gold_signals_hash;
57 my %gate_signals_hash;
61 s/(\[([0-9]+|[0-9]+:[0-9]+)\])$//;
62 $gold_signals_hash{$_}->{$fullname} = 1 unless /(^|\.)_[0-9]+_/;
67 s/(\[([0-9]+|[0-9]+:[0-9]+)\])$//;
68 $gate_signals_hash{$_}->{$fullname} = 1 unless /(^|\.)_[0-9]+_/;
72 for my $net (sort keys %gold_signals_hash) {
73 next unless exists $gate_signals_hash{$net};
74 # next unless $net eq "tst_bench_top.i2c_top.byte_controller.bit_controller.cnt";
76 print "common signal: $net";
77 for my $fullname (keys $gold_signals_hash{$net}) {
78 $orig_net_names{$fullname} = 1;
80 for my $fullname (keys $gate_signals_hash{$net}) {
81 $orig_net_names{$fullname} = 1;
83 for my $net (sort keys %orig_net_names) {
85 print " $1" if /(\[([0-9]+|[0-9]+:[0-9]+)\])$/;
90 print "Loading gold vcd data..\n";
91 my $vcd_gold = parse_vcd
($fn_gold, {siglist
=> \
@signals});
93 print "Loading gate vcd data..\n";
94 my $vcd_gate = parse_vcd
($fn_gate, {siglist
=> \
@signals});
96 # print Dumper($vcd_gold);
97 # print Dumper($vcd_gate);
100 my $signal_maxlen = 8;
106 my ($net, $val) = @_;
107 my $thislen = length $val;
108 $thislen += $1 if $net =~ /\[([0-9]+)\]$/;
109 $thislen += $1 if $net =~ /\[([0-9]+):[0-9]+\]$/;
110 $signal_maxlen = $thislen if $signal_maxlen < $thislen;
113 print "Processing gold vcd data..\n";
114 for my $key (keys %$vcd_gold) {
115 for my $net (@
{$vcd_gold->{$key}->{'nets'}}) {
116 my $netname = $net->{'hier'} . "." . $net->{'name'};
117 for my $tv (@
{$vcd_gold->{$key}->{'tv'}}) {
118 my $time = int($tv->[0]);
119 my $value = $tv->[1];
120 checklen
($netname, $value);
121 $data_gold->{$time}->{$netname} = $value;
127 print "Processing gate vcd data..\n";
128 for my $key (keys %$vcd_gate) {
129 for my $net (@
{$vcd_gate->{$key}->{'nets'}}) {
130 my $netname = $net->{'hier'} . "." . $net->{'name'};
131 for my $tv (@
{$vcd_gate->{$key}->{'tv'}}) {
132 my $time = int($tv->[0]);
133 my $value = $tv->[1];
134 checklen
($netname, $value);
135 $data_gate->{$time}->{$netname} = $value;
141 $signal_maxlen = $opt_width if $opt_width > 0;
149 sub set_state_bit
($$$$)
151 my ($state, $net, $bit, $value) = @_;
153 @data = split //, $state->{$net} if exists $state->{$net};
154 unshift @data, "-" while $#data < $bit;
155 $data[$#data - $bit] = $value;
156 $state->{$net} = join "", @data;
157 $signal_sync{$net} = 1 unless exists $signal_sync{$net};
158 $touched_nets{$net} = 1;
163 my ($state, $net, $value) = @_;
165 if ($net =~ /(.*)\[([0-9]+)\]$/) {
166 set_state_bit
($state, $1, $2, $value);
170 if ($net =~ /(.*)\[([0-9]+):([0-9]+)\]$/) {
171 my ($n, $u, $d) = ($1, $2, $3);
172 my @bits = split //, $value;
173 my $extbit = $bits[0] eq "1" ?
"0" : $bits[0];
174 unshift @bits, $extbit while $#bits < $u - $d;
175 set_state_bit
($state, $n, $u--, shift @bits) while $u >= $d;
179 $state->{$net} = $value;
180 $signal_sync{$net} = 1 unless exists $signal_sync{$net};
181 $touched_nets{$net} = 1;
187 return 1 if $a eq $b;
189 my @a = split //, $a;
190 my @b = split //, $b;
192 my $trail_a = $#a < 0 ?
'-' : $a[0] eq '1' ?
'0' : $a[0];
193 my $trail_b = $#b < 0 ?
'-' : $b[0] eq '1' ?
'0' : $b[0];
195 unshift @a, $trail_a while $#a < $#b;
196 unshift @b, $trail_b while $#b < $#a;
198 for (my $i = 0; $i <= $#a; $i++) {
199 next if $a[$i] eq "-" || $b[$i] eq "-";
200 return 0 if $a[$i] ne "x" && $a[$i] ne $b[$i];
206 # Message objects: .text, .time, .signal, .sync
209 print "Comparing vcd data..\n";
210 for my $time (sort { $a <=> $b } keys %times)
213 for my $net (keys %{$data_gold->{$time}}) {
214 set_state
(\
%state_gold, $net, $data_gold->{$time}->{$net});
216 for my $net (keys %{$data_gate->{$time}}) {
217 set_state
(\
%state_gate, $net, $data_gate->{$time}->{$net});
219 for my $net (sort keys %touched_nets) {
220 my ($stgo, $stga) = ('-', '-');
221 $stgo = $state_gold{$net} if exists $state_gold{$net};
222 $stga = $state_gate{$net} if exists $state_gate{$net};
223 if (cmp_signal
($stgo, $stga)) {
224 next if $signal_sync{$net};
226 $message->{text
} = sprintf "%-10s %-20d %-*s %-*s %s\n", "<sync>", $time, $signal_maxlen, $stgo, $signal_maxlen, $stga, $net;
227 $message->{time} = $time;
228 $message->{signal
} = $net;
229 $message->{sync
} = 1;
230 push @messages, $message;
231 $signal_sync{$net} = 1;
234 $message->{text
} = sprintf "%-10d %-20d %-*s %-*s %s\n", $diffcount, $time, $signal_maxlen, $stgo, $signal_maxlen, $stga, $net;
235 $message->{time} = $time;
236 $message->{signal
} = $net;
237 $message->{sync
} = 0;
238 push @messages, $message;
239 $signal_sync{$net} = 0;
245 print "Found $diffcount differences.\n";
247 if ($opt_delay > 0) {
249 my $removed_diff_count = 0;
250 for (my $i = 0; $i <= $#messages; $i++) {
251 my $message = $messages[$i];
252 $message->{deleted
} = 0;
253 $per_net_history{$message->{signal
}} = [ ] unless exists $per_net_history{$message->{signal
}};
254 if ($message->{sync
}) {
256 for my $j (@
{$per_net_history{$message->{signal
}}}) {
257 my $m = $messages[$j];
258 if ($m->{time} + $opt_delay >= $message->{time}) {
260 $removed_diff_count++;
265 $message->{deleted
} = 1 if $deleted_all;
266 $per_net_history{$message->{signal
}} = [ ];
268 push @
{$per_net_history{$message->{signal
}}}, $i;
272 for my $message (@messages) {
273 push @new_messages, $message unless $message->{deleted
};
275 @messages = @new_messages;
276 printf "Removed %d differences using delay filtering.\n", $removed_diff_count;
277 $diffcount = $diffcount - $removed_diff_count;
280 if ($#messages >= 0) {
281 printf "\n%-10s %-20s %-*s %-*s %s\n", "count", "time", $signal_maxlen, "gold", $signal_maxlen, "gate", "net" if $diffcount++ == 0;
282 for (my $i = 0; $i <= $#messages; $i++) {
283 printf "%s", $messages[$i]->{text
};
287 exit ($diffcount > 0 ?
1 : 0);