#!/usr/bin/perl -w
######################################################################
#
# Copyright 2007-2016 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.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
######################################################################

# DESCRIPTION: Debugging of bison output

use strict;

my $Debug;

my %declared;
my %used;

my $body = 0;
my $rule = "";
my $lineno = 0;
foreach my $line (<STDIN>) {
    $lineno++;
    chomp $line;
    $line =~ s!//.*$!!g;
    $line =~ s!\s+! !g;
    next if $line eq '';
    if ($line =~ m!^\%\%!) {
	$body++;
    } elsif ($body == 1) {
	$rule .= $line;
	if ($line =~ m!^\s*;\s*$!) {
	    #print "Rule: $rule\n";
	    ($rule =~ /^([a-zA-Z0-9_]+)(<\S+>)?:(.*)$/) or die "%Error: No rule name: $1\n";
	    my $rulename = $1; my $preaction = $3;
	    $declared{$rulename} = $lineno;
	    $preaction =~ s/\{[^\}]*\}/ /g;
	    #print "RULEN $rulename PA $preaction\n" if $Debug;
	    $rule = '';
	    foreach my $ref (split /\s+/, $preaction) {
		next if $ref !~ /^[a-zA-Z]/;
		next if $ref eq $rulename;
		if (!$used{$ref} && $declared{$ref}) {
		    print "   %Warning: $lineno: $ref used by $rulename after declaration\n";
		}
		$used{$ref} = $lineno;
		print "  ref $ref\n" if $Debug;
	    }
	}
    }
}

# Local Variables:
# compile-command: "./bisonreader < ../src/verilog.y"
# End: