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# See copyright, etc in below POD section.
######################################################################
=pod
=head1 NAME
Verilog::Language - Verilog language utilities
=head1 SYNOPSIS
use Verilog::Language;
$result = Verilog::Language::is_keyword("wire"); # true
$result = Verilog::Language::is_compdirect("`notundef"); # false
$result = Verilog::Language::number_value("4'b111"); # 8
$result = Verilog::Language::number_bits("32'h1b"); # 32
$result = Verilog::Language::number_signed("1'sh1"); # 1
@vec = Verilog::Language::split_bus("[31,5:4]"); # 31, 5, 4
@vec = Verilog::Language::split_bus_nocomma("[31:29]"); # 31, 30, 29
$result = Verilog::Language::strip_comments("a/*b*/c"); # ac
=head1 DESCRIPTION
Verilog::Language provides general utilities for using the Verilog
Language, such as parsing numbers or determining what keywords exist.
General functions will be added as needed.
=head1 FUNCTIONS
=over 4
=item Verilog::Language::is_keyword($symbol_string)
Return true if the given symbol string is a Verilog reserved keyword.
Value indicates the language standard as per the `begin_keywords macro,
'1364-1995', '1364-2001', '1364-2005', '1800-2005', '1800-2009',
'1800-2012', '1800-2017', '1800-2023', or 'VAMS'.
=item Verilog::Language::is_compdirect($symbol_string)
Return true if the given symbol string is a Verilog compiler directive.
=item Verilog::Language::is_gateprim($symbol_string)
Return true if the given symbol is a built in gate primitive; for example
"buf", "xor", etc.
=item Verilog::Language::language_keywords($year)
Returns a hash for keywords for given language standard year, where the
value of the hash is the standard in which it was defined.
=item Verilog::Language::language_standard($year)
Sets the language standard to indicate what are keywords. If undef, all
standards apply. The year is indicates the language standard as per the
`begin_keywords macro, '1364-1995', '1364-2001', '1364-2005', '1800-2005'
'1800-2009', '1800-2012', '1800-2017', or '1800-2023'.
=item Verilog::Language::language_maximum
Returns the greatest language currently standardized, presently
'1800-2023'.
=item Verilog::Language::number_bigint($number_string)
Return the numeric value of a Verilog value stored as a Math::BigInt, or
undef if incorrectly formed. You must 'use Math::BigInt' yourself before
calling this function. Note bigints do not have an exact size, so NOT of a
Math::BigInt may return a different value than verilog. See also
number_value and number_bitvector.
=item Verilog::Language::number_bits($number_string)
Return the number of bits in a value string, or undef if incorrectly
formed, _or_ not specified.
=item Verilog::Language::number_bitvector($number_string)
Return the numeric value of a Verilog value stored as a Bit::Vector, or
undef if incorrectly formed. You must 'use Bit::Vector' yourself before
calling this function. The size of the Vector will be that returned by
number_bits.
=item Verilog::Language::number_signed($number_string)
Return true if the Verilog value is signed, else undef.
=item Verilog::Language::number_value($number_string)
Return the numeric value of a Verilog value, or undef if incorrectly
formed. It ignores any signed Verilog attributes, but is is returned as a
perl signed integer, so it may fail for over 31 bit values. See also
number_bigint and number_bitvector.
=item Verilog::Language::split_bus($bus)
Return a list of expanded arrays. When passed a string like
"foo[5:1:2,10:9]", it will return a array with ("foo[5]", "foo[3]", ...).
It correctly handles connectivity expansion also, so that "x[1:0] = y[3:0]"
will get intuitive results.
=item Verilog::Language::split_bus_nocomma($bus)
As with split_bus, but faster. Only supports simple decimal colon
separated array specifications, such as "foo[3:0]".
=item Verilog::Language::strip_comments($text)
Return text with any // or /**/ comments stripped, correctly handing quoted
strings. Newlines will be preserved in this process.
=back
=head1 DISTRIBUTION
Verilog-Perl is part of the L<https://www.veripool.org/> free Verilog EDA
software tool suite. The latest version is available from CPAN and from
Copyright 2000-2024 by Wilson Snyder. This package is free software; you
can redistribute it and/or modify it under the terms of either the GNU
Lesser General Public License Version 3 or the Perl Artistic License Version 2.0.
=head1 AUTHORS
Wilson Snyder <wsnyder@wsnyder.org>
=head1 SEE ALSO
L<Verilog-Perl>,
L<Verilog::EditFiles>
L<Verilog::Parser>,
L<Verilog::ParseSig>,
L<Verilog::Getopt>
And the L<https://www.veripool.org/verilog-mode>Verilog-Mode package for Emacs.
=cut
######################################################################
require 5.000;
require Exporter;
use strict;
use vars qw($VERSION %Keyword %Keywords %Compdirect $Standard %Gateprim);
use Carp;
######################################################################
#### Configuration Section
$VERSION = '3.482';
######################################################################
#### Internal Variables
foreach my $kwd (qw(
always and assign begin buf bufif0 bufif1 case
casex casez cmos deassign default defparam
disable else end endcase endfunction endmodule
endprimitive endspecify endtable endtask event
for force forever fork function highz0
highz1 if initial inout input integer join large
macromodule medium module nand negedge
nmos nor not notif0 notif1 or output parameter
pmos posedge primitive pull0 pull1 pulldown
pullup rcmos real realtime reg release repeat
rnmos rpmos rtran rtranif0 rtranif1 scalared
small specify strength strong0 strong1
supply0 supply1 table task time tran tranif0
tranif1 tri tri0 tri1 triand trior trireg
vectored wait wand weak0 weak1 while wire wor
xnor xor
)) { $Keywords{'1364-1995'}{$kwd} = '1364-1995'; }
foreach my $kwd (qw(
automatic cell config design edge endconfig endgenerate
generate genvar ifnone incdir include instance liblist
library localparam
noshowcancelled pulsestyle_ondetect pulsestyle_onevent
showcancelled signed specparam unsigned use
)) { $Keywords{'1364-2001'}{$kwd} = '1364-2001'; }
foreach my $kwd (qw(
uwire
)) { $Keywords{'1364-2005'}{$kwd} = '1364-2005'; }
foreach my $kwd (qw(
alias always_comb always_ff always_latch assert assume
before bind bins binsof bit break byte chandle class
clocking const constraint context continue cover
covergroup coverpoint cross dist do endclass endclocking
endgroup endinterface endpackage endprogram endproperty
endsequence enum expect export extends extern final
first_match foreach forkjoin iff ignore_bins
illegal_bins import inside int interface intersect
join_any join_none local logic longint matches modport
new null package packed priority program property
protected pure rand randc randcase randsequence ref
return sequence shortint shortreal solve static string
struct super tagged this throughout timeprecision
timeunit type typedef union unique var virtual void
wait_order wildcard with within
)) { $Keywords{'1800-2005'}{$kwd} = '1800-2005'; }
foreach my $kwd (qw(
accept_on checker endchecker eventually global implies
let nexttime reject_on restrict s_always s_eventually
s_nexttime s_until s_until_with strong sync_accept_on
sync_reject_on unique0 until until_with untyped weak
)) { $Keywords{'1800-2009'}{$kwd} = '1800-2009'; }
foreach my $kwd (qw(
implements nettype interconnect soft
)) { $Keywords{'1800-2012'}{$kwd} = '1800-2012'; }
foreach my $kwd (qw(
)) { $Keywords{'1800-2017'}{$kwd} = '1800-2017'; }
foreach my $kwd (qw(
)) { $Keywords{'1800-2023'}{$kwd} = '1800-2023'; }
foreach my $kwd (qw(
above abs absdelay abstol ac_stim access acos acosh
aliasparam analog analysis asin asinh assert atan atan2
atanh branch ceil connect connectmodule connectrules
continuous cos cosh cross ddt ddt_nature ddx discipline
discrete domain driver_update endconnectrules
enddiscipline endnature endparamset exclude exp
final_step flicker_noise floor flow from ground hypot
idt idt_nature idtmod inf initial_step laplace_nd
laplace_np laplace_zd laplace_zp last_crossing limexp
ln log max merged min nature net_resolution noise_table
paramset potential pow resolveto sin sinh slew split
sqrt string tan tanh timer transition units white_noise
wreal zi_nd zi_np zi_zd zi_zp
)) { $Keywords{'VAMS'}{$kwd} = 'VAMS'; }
foreach my $kwd (
# Speced
"`celldefine",
"`define", # Preprocessor
"`else", # Preprocessor
"`endcelldefine",
"`endif", # Preprocessor
"`ifdef", # Preprocessor
"`include", # Preprocessor
"`nounconnected_drive",
"`resetall",
"`timescale",
"`unconnected_drive",
"`undef", # Preprocessor
"`undefineall", # Preprocessor
# Commercial Extensions
"`accelerate", # Verilog-XL compatibility
"`autoexpand_vectornets", # Verilog-XL compatibility
"`default_decay_time", # Verilog spec - delays only
"`default_trireg_strength", # Verilog spec
"`delay_mode_distributed", # Verilog spec - delays only
"`delay_mode_path", # Verilog spec - delays only
"`delay_mode_unit", # Verilog spec - delays only
"`delay_mode_zero", # Verilog spec - delays only
"`disable_portfaults", # Verilog-XL compatibility
"`enable_portfaults", # Verilog-XL compatibility
"`endprotect", # Many tools - pre encryption
"`endprotected", # Many tools - post encryption
"`expand_vectornets", # Verilog-XL compatibility
"`noaccelerate", # Verilog-XL compatibility
"`noexpand_vectornets", # Verilog-XL compatibility
"`noremove_gatenames", # Verilog-XL compatibility
"`noremove_netnames", # Verilog-XL compatibility
"`nosuppress_faults", # Verilog-XL compatibility
"`nounconnected_drive", # Verilog-XL compatibility
"`portcoerce", # Verilog-XL compatibility
"`protect", # Many tools - pre encryption
"`protected", # Many tools - post encryption
"`remove_gatenames", # Verilog-XL compatibility
"`remove_netnames", # Verilog-XL compatibility
"`suppress_faults", # Verilog-XL compatibility
) { $Keywords{$kwd}{'1364-1995'} = $Compdirect{$kwd} = '1364-1995'; }
foreach my $kwd (
"`default_nettype", "`elsif", "`undef", "`ifndef",
"`file", "`line",
) { $Keywords{$kwd}{'1364-2001'} = $Compdirect{$kwd} = '1364-2001'; }
foreach my $kwd (
"`pragma",
) { $Keywords{$kwd}{'1364-2005'} = $Compdirect{$kwd} = '1364-2005'; }
foreach my $kwd (
"`default_discipline", "`default_transition",
) { $Keywords{$kwd}{'1364-2005'} = $Compdirect{$kwd} = '1364-2005'; }
language_standard(language_maximum()); # Default standard
foreach my $kwd (qw(
and buf bufif0 bufif1 cmos nand nmos nor not notif0
notif1 or pmos pulldown pullup rcmos rnmos rpmos rtran
rtranif0 rtranif1 tran tranif0 tranif1 xnor xor
)) { $Gateprim{$kwd} = '1364-1995'; }
######################################################################
#### Keyword utilities
sub language_maximum {
return "1800-2023";
}
sub _language_kwd_hash {
my $standard = shift;
my @subsets;
if ($standard eq '1995' || $standard eq '1364-1995') {
$Standard = '1364-1995';
@subsets = ('1364-1995');
} elsif ($standard eq '2001' || $standard eq '1364-2001' || $standard eq '1364-2001-noconfig') {
$Standard = '1364-2001';
@subsets = ('1364-2001',
'1364-1995');
} elsif ($standard eq '1364-2005') {
$Standard = '1364-2005';
@subsets = ('1364-2005',
'1364-2001', '1364-1995');
} elsif ($standard eq 'sv31' || $standard eq '1800-2005') {
$Standard = '1800-2005';
@subsets = ('1800-2005',
'1364-2005', '1364-2001', '1364-1995');
} elsif ($standard eq '1800-2009') {
$Standard = '1800-2009';
@subsets = ('1800-2009', '1800-2005',
'1364-2005', '1364-2001', '1364-1995');
} elsif ($standard eq '1800-2012') {
$Standard = '1800-2012';
@subsets = ('1800-2012', '1800-2009', '1800-2005',
'1364-2005', '1364-2001', '1364-1995');
} elsif ($standard eq '1800-2017') {
$Standard = '1800-2017';
@subsets = ('1800-2017', '1800-2012', '1800-2009', '1800-2005',
'1364-2005', '1364-2001', '1364-1995');
} elsif ($standard eq 'latest' || $standard eq '1800-2023') {
$Standard = '1800-2023';
@subsets = ('1800-2023', '1800-2017', '1800-2012', '1800-2009', '1800-2005',
'1364-2005', '1364-2001', '1364-1995');
} elsif ($standard =~ /^V?AMS/) {
$Standard = 'VAMS';
@subsets = ('VAMS',
'1364-2005', '1364-2001', '1364-1995');
} else {
croak "%Error: Verilog::Language::language_standard passed bad value: $standard,";
}
# Update keyword list to present language
# (We presume the language_standard rarely changes, so it's faster to compute the list.)
my %keywords = ();
foreach my $ss (@subsets) {
foreach my $kwd (%{$Keywords{$ss}}) {
$keywords{$kwd} = $ss;
}
}
return %keywords;
}
sub language_standard {
my $standard = shift;
if (defined $standard) {
%Keyword = _language_kwd_hash($standard);
}
return $Standard;
}
sub language_keywords {
my $standard = shift || $Standard;
return _language_kwd_hash($standard);
}
sub is_keyword {
my $symbol = shift;
return ($Keyword{$symbol});
}
sub is_compdirect {
my $symbol = shift;
return ($Compdirect{$symbol});
}
sub is_gateprim {
my $symbol = shift;
return ($Gateprim{$symbol});
}
######################################################################
#### String utilities
sub strip_comments {
return $_[0] if $_[0] !~ m!/!s; # Fast path
my $text = shift;
# Spec says that // has no special meaning inside /**/
my $quote; my $olcmt; my $cmt;
my $out = "";
while ($text =~ m!(.*?)(//|/\*|\*/|\n|\"|$)!sg) {
$out .= $1 if !$olcmt && !$cmt;
my $t = $2;
if ($2 eq '"') {
$out .= $t;
$quote = ! $quote;
} elsif (!$quote && !$olcmt && $t eq '/*') {
$cmt = 1;
} elsif (!$quote && !$cmt && $t eq '//') {
$olcmt = 1;
} elsif ($cmt && $t eq '*/') {
$cmt = 0;
} elsif ($t eq "\n") {
$olcmt = 0;
$out .= $t;
} else {
$out .= $t if !$olcmt && !$cmt;
}
}
return $out;
}
######################################################################
#### Numeric utilities
sub number_bits {
my $number = shift;
if ($number =~ /^\s*([0-9]+)\s*\'/i) {
return $1;
}
return undef;
}
sub number_signed {
my $number = shift;
if ($number =~ /\'\s*s/i) {
return 1;
}
return undef;
}
sub number_value {
my $number = shift;
$number =~ s/[_ ]//g;
if ($number =~ /\'s?h([0-9a-f]+)$/i) {
return (hex ($1));
}
elsif ($number =~ /\'s?o([0-9a-f]+)$/i) {
return (oct ($1));
}
elsif ($number =~ /\'s?b([0-1]+)$/i) {
my $val = 0;
$number = $1;
foreach my $bit (split(//, $number)) {
$val = ($val<<1) | ($bit=='1'?1:0);
}
return ($val);
}
elsif ($number =~ /\'s?d?([0-9]+)$/i
|| $number =~ /^(-?[0-9]+)$/i) {
return ($1);
}
return undef;
}
sub number_bigint {
my $number = shift;
$number =~ s/[_ ]//g;
if ($number =~ /\'s?h([0-9a-f]+)$/i) {
return (Math::BigInt->new("0x".$1));
}
elsif ($number =~ /\'s?o([0-9a-f]+)$/i) {
my $digits = $1;
my $vec = Math::BigInt->new();
my $len = length($digits);
my $bit = 0;
for (my $index=$len-1; $index>=0; $index--, $bit+=3) {
my $digit = substr($digits,$index,1);
my $val = Math::BigInt->new($digit);
$val = $val->blsft($bit,2);
$vec->bior($val);
}
return ($vec);
}
elsif ($number =~ /\'s?b([0-1]+)$/i) {
return (Math::BigInt->new("0b".$1));
}
elsif ($number =~ /\'s?d?0*([0-9]+)$/i
|| $number =~ /^0*([0-9]+)$/i) {
return (Math::BigInt->new($1));
}
return undef;
}
sub number_bitvector {
my $number = shift;
$number =~ s/[_ ]//g;
my $bits = number_bits($number) || 32;
if ($number =~ /\'s?h([0-9a-f]+)$/i) {
return (Bit::Vector->new_Hex($bits,$1));
}
elsif ($number =~ /\'s?o([0-9a-f]+)$/i) {
my $digits = $1;
my $vec = Bit::Vector->new($bits);
my $len = length($digits);
my $bit = 0;
for (my $index=$len-1; $index>=0; $index--, $bit+=3) {
my $digit = substr($digits,$index,1);
$vec->Bit_On($bit+2) if ($digit & 4);
$vec->Bit_On($bit+1) if ($digit & 2);
$vec->Bit_On($bit+0) if ($digit & 1);
}
return ($vec);
}
elsif ($number =~ /\'s?b([0-1]+)$/i) {
return (Bit::Vector->new_Bin($bits,$1));
}
elsif ($number =~ /\'s?d?([0-9]+)$/i
|| $number =~ /^([0-9]+)$/i) {
return (Bit::Vector->new_Dec($bits,$1));
}
return undef;
}
######################################################################
#### Signal utilities
sub split_bus {
my $bus = shift;
if ($bus !~ /\[/) {
# Fast case: No bussing
return $bus;
} elsif ($bus =~ /^([^\[]+\[)([0-9]+):([0-9]+)(\][^\]]*)$/) {
# Middle speed case: Simple max:min
my $bit;
my @vec = ();
if ($2 >= $3) {
for ($bit = $2; $bit >= $3; $bit --) {
push @vec, $1 . $bit . $4;
}
} else {
for ($bit = $2; $bit <= $3; $bit ++) {
push @vec, $1 . $bit . $4;
}
}
return @vec;
} else {
# Complex case: x:y:z,p,... etc
# Do full parsing
my @pretext = (); # [brnum]
my @expanded = (); # [brnum][bitoccurance]
my $inbra = 0;
my $brnum = 0;
my ($beg,$end,$step);
foreach (split (/([:\]\[,])/, $bus)) {
if (/^\[/) {
$inbra = 1;
$pretext[$brnum] .= $_;
}
if (!$inbra) {
# Not in bracket, just remember text
$pretext[$brnum] .= $_;
next;
}
if (/[\],]/) {
if (defined $beg) {
# End of bus piece
#print "Got seg $beg $end $step\n";
my $bit;
if ($beg >= $end) {
for ($bit = $beg; $bit >= $end; $bit -= $step) {
push @{$expanded[$brnum]}, $bit;
}
} else {
for ($bit = $beg; $bit <= $end; $bit += $step) {
push @{$expanded[$brnum]}, $bit;
}
}
}
$beg = undef;
# Now what?
if (/^\]/) {
$inbra = 0;
$brnum++;
$pretext[$brnum] .= $_;
}
elsif (/,/) {
$inbra = 1;
}
} elsif (/:/) {
$inbra++;
}
else {
if ($inbra == 1) { # Begin value
$beg = $end = number_value($_); # [2'b11:2'b00] is legal
$step = 1;
} elsif ($inbra == 2) { # End value
$end = number_value($_); # [2'b11:2'b00] is legal
} elsif ($inbra == 3) { # Middle value
$step = number_value($_); # [2'b11:2'b00] is legal
}
# Else ignore extra colons
}
}
# Determine max size of any bracket expansion array
my $br;
my $max_size = $#{$expanded[0]};
for ($br=1; $br<$brnum; $br++) {
my $len = $#{$expanded[$br]};
if ($len < 0) {
push @{$expanded[$br]}, "";
$len = 0;
}
$max_size = $len if $max_size < $len;
}
my $i;
my @vec = ();
for ($i=0; $i<=$max_size; $i++) {
$bus = "";
for ($br=0; $br<$brnum; $br++) {
#print "i $i br $br >", $pretext[$br],"<\n";
$bus .= $pretext[$br] . $expanded[$br][$i % (1+$#{$expanded[$br]})];
}
$bus .= $pretext[$br]; # Trailing stuff
push @vec, $bus;
}
return @vec;
}
}
sub split_bus_nocomma {
# Faster version of split_bus
my $bus = shift;
if ($bus !~ /:/) {
# Fast case: No bussing
return $bus;
} elsif ($bus =~ /^([^\[]+\[)([0-9]+):([0-9]+)(\][^\]]*)$/) {
# Middle speed case: Simple max:min
my $bit;
my @vec = ();
if ($2 >= $3) {
for ($bit = $2; $bit >= $3; $bit --) {
push @vec, $1 . $bit . $4;
}
} else {
for ($bit = $2; $bit <= $3; $bit ++) {
push @vec, $1 . $bit . $4;
}
}
return @vec;
} else {
# Complex case: x:y etc
# Do full parsing
my @pretext = (); # [brnum]
my @expanded = (); # [brnum][bitoccurance]
my $inbra = 0;
my $brnum = 0;
my ($beg,$end);
foreach (split (/([:\]\[])/, $bus)) {
if (/^\[/) {
$inbra = 1;
$pretext[$brnum] .= $_;
}
if (!$inbra) {
# Not in bracket, just remember text
$pretext[$brnum] .= $_;
next;
}
if (/[\]]/) {
if (defined $beg) {
# End of bus piece
#print "Got seg $beg $end\n";
my $bit;
if ($beg >= $end) {
for ($bit = $beg; $bit >= $end; $bit--) {
push @{$expanded[$brnum]}, $bit;
}
} else {
for ($bit = $beg; $bit <= $end; $bit++) {
push @{$expanded[$brnum]}, $bit;
}
}
}
$beg = undef;
# Now what?
if (/^\]/) {
$inbra = 0;
$brnum++;
$pretext[$brnum] .= $_;
}
} elsif (/:/) {
$inbra++;
}
else {
if ($inbra == 1) { # Begin value
$beg = $end = $_;
} elsif ($inbra == 2) { # End value
$end = $_;
}
# Else ignore extra colons
}
}
# Determine max size of any bracket expansion array
my $br;
my $max_size = $#{$expanded[0]};
for ($br=1; $br<$brnum; $br++) {
my $len = $#{$expanded[$br]};
if ($len < 0) {
push @{$expanded[$br]}, "";
$len = 0;
}
$max_size = $len if $max_size < $len;
}
my $i;
my @vec = ();
for ($i=0; $i<=$max_size; $i++) {
$bus = "";
for ($br=0; $br<$brnum; $br++) {
#print "i $i br $br >", $pretext[$br],"<\n";
$bus .= $pretext[$br] . $expanded[$br][$i % (1+$#{$expanded[$br]})];
}
$bus .= $pretext[$br]; # Trailing stuff
push @vec, $bus;
}
return @vec;
}
}
######################################################################
#### Package return
1;