JavaScriptCore/create_hash_table - WebKit - Git at Google

 #! /usr/bin/perl -w
 #
 # Static Hashtable Generator
 #
 # (c) 2000-2002 by Harri Porten <porten@kde.org> and
 #                  David Faure <faure@kde.org>
 # Modified (c) 2004 by Nikolas Zimmermann <wildfox@kde.org>
 # Copyright (C) 2007, 2008, 2009 Apple Inc. All rights reserved.
 #
 # This library is free software; you can redistribute it and/or
 # modify it under the terms of the GNU Lesser General Public
 # License as published by the Free Software Foundation; either
 # version 2 of the License, or (at your option) any later version.
 #
 # This library 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
 # Lesser General Public License for more details.
 #
 # You should have received a copy of the GNU Lesser General Public
 # License along with this library; if not, write to the Free Software
 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 #

 use strict;

 my $file = $ARGV[0];
 shift;
 my $includelookup = 0;

 # Use -i as second argument to make it include "Lookup.h"
 $includelookup = 1 if (defined($ARGV[0]) && $ARGV[0] eq "-i");

 # Use -n as second argument to make it use the third argument as namespace parameter ie. -n KDOM
 my $useNameSpace = $ARGV[1] if (defined($ARGV[0]) && $ARGV[0] eq "-n");

 print STDERR "Creating hashtable for $file\n";
 open(IN, $file) or die "No such file $file";

 my @keys = ();
 my @attrs = ();
 my @values = ();
 my @hashes = ();

 my $inside = 0;
 my $name;
 my $pefectHashSize;
 my $compactSize;
 my $compactHashSizeMask;
 my $banner = 0;
 sub calcPerfectHashSize();
 sub calcCompactHashSize();
 sub output();
 sub jsc_ucfirst($);
 sub hashValue($);

 while (<IN>) {
     chomp;
     s/^\s+//;
     next if /^\#|^$/; # Comment or blank line. Do nothing.
     if (/^\@begin/ && !$inside) {
         if (/^\@begin\s*([:_\w]+)\s*\d*\s*$/) {
             $inside = 1;
             $name = $1;
         } else {
             print STDERR "WARNING: \@begin without table name, skipping $_\n";
         }
     } elsif (/^\@end\s*$/ && $inside) {
         calcPerfectHashSize();
         calcCompactHashSize();
         output();

         @keys = ();
         @attrs = ();
         @values = ();
         @hashes = ();

         $inside = 0;
     } elsif (/^(\S+)\s*(\S+)\s*([\w\|]*)\s*(\w*)\s*$/ && $inside) {
         my $key = $1;
         my $val = $2;
         my $att = $3;
         my $param = $4;

         push(@keys, $key);
         push(@attrs, length($att) > 0 ? $att : "0");

         if ($att =~ m/Function/) {
             push(@values, { "type" => "Function", "function" => $val, "params" => (length($param) ? $param : "") });
             #printf STDERR "WARNING: Number of arguments missing for $key/$val\n" if (length($param) == 0);
         } elsif (length($att)) {
             my $get = $val;
             my $put = !($att =~ m/ReadOnly/) ? "set" . jsc_ucfirst($val) : "0";
             push(@values, { "type" => "Property", "get" => $get, "put" => $put });
         } else {
             push(@values, { "type" => "Lexer", "value" => $val });
         }
         push(@hashes, hashValue($key));
     } elsif ($inside) {
         die "invalid data {" . $_ . "}";
     }
 }

 die "missing closing \@end" if ($inside);

 sub jsc_ucfirst($)
 {
     my ($value) = @_;

     if ($value =~ /js/) {
         $value =~ s/js/JS/;
         return $value;
     }

     return ucfirst($value);
 }


 sub ceilingToPowerOf2
 {
     my ($pefectHashSize) = @_;

     my $powerOf2 = 1;
     while ($pefectHashSize > $powerOf2) {
         $powerOf2 <<= 1;
     }

     return $powerOf2;
 }

 sub calcPerfectHashSize()
 {
 tableSizeLoop:
     for ($pefectHashSize = ceilingToPowerOf2(scalar @keys); ; $pefectHashSize += $pefectHashSize) {
         my @table = ();
         foreach my $key (@keys) {
             my $h = hashValue($key) % $pefectHashSize;
             next tableSizeLoop if $table[$h];
             $table[$h] = 1;
         }
         last;
     }
 }

 sub leftShift($$) {
     my ($value, $distance) = @_;
     return (($value << $distance) & 0xFFFFFFFF);
 }

 sub calcCompactHashSize()
 {
     my @table = ();
     my @links = ();
     my $compactHashSize = ceilingToPowerOf2(2 * @keys);
     $compactHashSizeMask = $compactHashSize - 1;
     $compactSize = $compactHashSize;
     my $collisions = 0;
     my $maxdepth = 0;
     my $i = 0;
     foreach my $key (@keys) {
         my $depth = 0;
         my $h = hashValue($key) % $compactHashSize;
         while (defined($table[$h])) {
             if (defined($links[$h])) {
                 $h = $links[$h];
                 $depth++;
             } else {
                 $collisions++;
                 $links[$h] = $compactSize;
                 $h = $compactSize;
                 $compactSize++;
             }
         }
         $table[$h] = $i;
         $i++;
         $maxdepth = $depth if ( $depth > $maxdepth);
     }
 }

 # Paul Hsieh's SuperFastHash
 # http://www.azillionmonkeys.com/qed/hash.html
 # Ported from UString..
 sub hashValue($) {
   my @chars = split(/ */, $_[0]);

   # This hash is designed to work on 16-bit chunks at a time. But since the normal case
   # (above) is to hash UTF-16 characters, we just treat the 8-bit chars as if they
   # were 16-bit chunks, which should give matching results

   my $EXP2_32 = 4294967296;

   my $hash = 0x9e3779b9;
   my $l    = scalar @chars; #I wish this was in Ruby --- Maks
   my $rem  = $l & 1;
   $l = $l >> 1;

   my $s = 0;

   # Main loop
   for (; $l > 0; $l--) {
     $hash   += ord($chars[$s]);
     my $tmp = leftShift(ord($chars[$s+1]), 11) ^ $hash;
     $hash   = (leftShift($hash, 16)% $EXP2_32) ^ $tmp;
     $s += 2;
     $hash += $hash >> 11;
     $hash %= $EXP2_32;
   }

   # Handle end case
   if ($rem !=0) {
     $hash += ord($chars[$s]);
     $hash ^= (leftShift($hash, 11)% $EXP2_32);
     $hash += $hash >> 17;
   }

   # Force "avalanching" of final 127 bits
   $hash ^= leftShift($hash, 3);
   $hash += ($hash >> 5);
   $hash = ($hash% $EXP2_32);
   $hash ^= (leftShift($hash, 2)% $EXP2_32);
   $hash += ($hash >> 15);
   $hash = $hash% $EXP2_32;
   $hash ^= (leftShift($hash, 10)% $EXP2_32);

   # this avoids ever returning a hash code of 0, since that is used to
   # signal "hash not computed yet", using a value that is likely to be
   # effectively the same as 0 when the low bits are masked
   $hash = 0x80000000  if ($hash == 0);

   return $hash;
 }

 sub output() {
     if (!$banner) {
         $banner = 1;
         print "// Automatically generated from $file using $0. DO NOT EDIT!\n";
     }

     my $nameEntries = "${name}Values";
     $nameEntries =~ s/:/_/g;

     print "\n#include \"Lookup.h\"\n" if ($includelookup);
     if ($useNameSpace) {
         print "\nnamespace ${useNameSpace} {\n";
         print "\nusing namespace JSC;\n";
     } else {
         print "\nnamespace JSC {\n";
     }
     my $count = scalar @keys + 1;
     print "\nstatic const struct HashTableValue ${nameEntries}\[$count\] = {\n";
     my $i = 0;
     foreach my $key (@keys) {
         my $firstValue = "";
         my $secondValue = "";

         if ($values[$i]{"type"} eq "Function") {
             $firstValue = $values[$i]{"function"};
             $secondValue = $values[$i]{"params"};
         } elsif ($values[$i]{"type"} eq "Property") {
             $firstValue = $values[$i]{"get"};
             $secondValue = $values[$i]{"put"};
         } elsif ($values[$i]{"type"} eq "Lexer") {
             $firstValue = $values[$i]{"value"};
             $secondValue = "0";
         }
         print "   { \"$key\", $attrs[$i], (intptr_t)$firstValue, (intptr_t)$secondValue },\n";
         $i++;
     }
     print "   { 0, 0, 0, 0 }\n";
     print "};\n\n";
     print "extern const struct HashTable $name =\n";
     print "    \{ $compactSize, $compactHashSizeMask, $nameEntries, 0 \};\n";
     print "} // namespace\n";
 }
	#! /usr/bin/perl -w
	#
	# Static Hashtable Generator
	#
	# (c) 2000-2002 by Harri Porten <porten@kde.org> and
	# David Faure <faure@kde.org>
	# Modified (c) 2004 by Nikolas Zimmermann <wildfox@kde.org>
	# Copyright (C) 2007, 2008, 2009 Apple Inc. All rights reserved.
	#
	# This library is free software; you can redistribute it and/or
	# modify it under the terms of the GNU Lesser General Public
	# License as published by the Free Software Foundation; either
	# version 2 of the License, or (at your option) any later version.
	#
	# This library 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
	# Lesser General Public License for more details.
	#
	# You should have received a copy of the GNU Lesser General Public
	# License along with this library; if not, write to the Free Software
	# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
	#

	use strict;

	my $file = $ARGV[0];
	shift;
	my $includelookup = 0;

	# Use -i as second argument to make it include "Lookup.h"
	$includelookup = 1 if (defined($ARGV[0]) && $ARGV[0] eq "-i");

	# Use -n as second argument to make it use the third argument as namespace parameter ie. -n KDOM
	my $useNameSpace = $ARGV[1] if (defined($ARGV[0]) && $ARGV[0] eq "-n");

	print STDERR "Creating hashtable for $file\n";
	open(IN, $file) or die "No such file $file";

	my @keys = ();
	my @attrs = ();
	my @values = ();
	my @hashes = ();

	my $inside = 0;
	my $name;
	my $pefectHashSize;
	my $compactSize;
	my $compactHashSizeMask;
	my $banner = 0;
	sub calcPerfectHashSize();
	sub calcCompactHashSize();
	sub output();
	sub jsc_ucfirst($);
	sub hashValue($);

	while (<IN>) {
	chomp;
	s/^\s+//;
	next if /^\#\|^$/; # Comment or blank line. Do nothing.
	if (/^\@begin/ && !$inside) {
	if (/^\@begin\s([:_\w]+)\s\d\s$/) {
	$inside = 1;
	$name = $1;
	} else {
	print STDERR "WARNING: \@begin without table name, skipping $_\n";
	}
	} elsif (/^\@end\s*$/ && $inside) {
	calcPerfectHashSize();
	calcCompactHashSize();
	output();

	@keys = ();
	@attrs = ();
	@values = ();
	@hashes = ();

	$inside = 0;
	} elsif (/^(\S+)\s(\S+)\s([\w\\|])\s(\w)\s$/ && $inside) {
	my $key = $1;
	my $val = $2;
	my $att = $3;
	my $param = $4;

	push(@keys, $key);
	push(@attrs, length($att) > 0 ? $att : "0");

	if ($att =~ m/Function/) {
	push(@values, { "type" => "Function", "function" => $val, "params" => (length($param) ? $param : "") });
	#printf STDERR "WARNING: Number of arguments missing for $key/$val\n" if (length($param) == 0);
	} elsif (length($att)) {
	my $get = $val;
	my $put = !($att =~ m/ReadOnly/) ? "set" . jsc_ucfirst($val) : "0";
	push(@values, { "type" => "Property", "get" => $get, "put" => $put });
	} else {
	push(@values, { "type" => "Lexer", "value" => $val });
	}
	push(@hashes, hashValue($key));
	} elsif ($inside) {
	die "invalid data {" . $_ . "}";
	}
	}

	die "missing closing \@end" if ($inside);

	sub jsc_ucfirst($)
	{
	my ($value) = @_;

	if ($value =~ /js/) {
	$value =~ s/js/JS/;
	return $value;
	}

	return ucfirst($value);
	}


	sub ceilingToPowerOf2
	{
	my ($pefectHashSize) = @_;

	my $powerOf2 = 1;
	while ($pefectHashSize > $powerOf2) {
	$powerOf2 <<= 1;
	}

	return $powerOf2;
	}

	sub calcPerfectHashSize()
	{
	tableSizeLoop:
	for ($pefectHashSize = ceilingToPowerOf2(scalar @keys); ; $pefectHashSize += $pefectHashSize) {
	my @table = ();
	foreach my $key (@keys) {
	my $h = hashValue($key) % $pefectHashSize;
	next tableSizeLoop if $table[$h];
	$table[$h] = 1;
	}
	last;
	}
	}

	sub leftShift($$) {
	my ($value, $distance) = @_;
	return (($value << $distance) & 0xFFFFFFFF);
	}

	sub calcCompactHashSize()
	{
	my @table = ();
	my @links = ();
	my $compactHashSize = ceilingToPowerOf2(2 * @keys);
	$compactHashSizeMask = $compactHashSize - 1;
	$compactSize = $compactHashSize;
	my $collisions = 0;
	my $maxdepth = 0;
	my $i = 0;
	foreach my $key (@keys) {
	my $depth = 0;
	my $h = hashValue($key) % $compactHashSize;
	while (defined($table[$h])) {
	if (defined($links[$h])) {
	$h = $links[$h];
	$depth++;
	} else {
	$collisions++;
	$links[$h] = $compactSize;
	$h = $compactSize;
	$compactSize++;
	}
	}
	$table[$h] = $i;
	$i++;
	$maxdepth = $depth if ( $depth > $maxdepth);
	}
	}

	# Paul Hsieh's SuperFastHash
	# http://www.azillionmonkeys.com/qed/hash.html
	# Ported from UString..
	sub hashValue($) {
	my @chars = split(/ */, $_[0]);

	# This hash is designed to work on 16-bit chunks at a time. But since the normal case
	# (above) is to hash UTF-16 characters, we just treat the 8-bit chars as if they
	# were 16-bit chunks, which should give matching results

	my $EXP2_32 = 4294967296;

	my $hash = 0x9e3779b9;
	my $l = scalar @chars; #I wish this was in Ruby --- Maks
	my $rem = $l & 1;
	$l = $l >> 1;

	my $s = 0;

	# Main loop
	for (; $l > 0; $l--) {
	$hash += ord($chars[$s]);
	my $tmp = leftShift(ord($chars[$s+1]), 11) ^ $hash;
	$hash = (leftShift($hash, 16)% $EXP2_32) ^ $tmp;
	$s += 2;
	$hash += $hash >> 11;
	$hash %= $EXP2_32;
	}

	# Handle end case
	if ($rem !=0) {
	$hash += ord($chars[$s]);
	$hash ^= (leftShift($hash, 11)% $EXP2_32);
	$hash += $hash >> 17;
	}

	# Force "avalanching" of final 127 bits
	$hash ^= leftShift($hash, 3);
	$hash += ($hash >> 5);
	$hash = ($hash% $EXP2_32);
	$hash ^= (leftShift($hash, 2)% $EXP2_32);
	$hash += ($hash >> 15);
	$hash = $hash% $EXP2_32;
	$hash ^= (leftShift($hash, 10)% $EXP2_32);

	# this avoids ever returning a hash code of 0, since that is used to
	# signal "hash not computed yet", using a value that is likely to be
	# effectively the same as 0 when the low bits are masked
	$hash = 0x80000000 if ($hash == 0);

	return $hash;
	}

	sub output() {
	if (!$banner) {
	$banner = 1;
	print "// Automatically generated from $file using $0. DO NOT EDIT!\n";
	}

	my $nameEntries = "${name}Values";
	$nameEntries =~ s/:/_/g;

	print "\n#include \"Lookup.h\"\n" if ($includelookup);
	if ($useNameSpace) {
	print "\nnamespace ${useNameSpace} {\n";
	print "\nusing namespace JSC;\n";
	} else {
	print "\nnamespace JSC {\n";
	}
	my $count = scalar @keys + 1;
	print "\nstatic const struct HashTableValue ${nameEntries}\[$count\] = {\n";
	my $i = 0;
	foreach my $key (@keys) {
	my $firstValue = "";
	my $secondValue = "";

	if ($values[$i]{"type"} eq "Function") {
	$firstValue = $values[$i]{"function"};
	$secondValue = $values[$i]{"params"};
	} elsif ($values[$i]{"type"} eq "Property") {
	$firstValue = $values[$i]{"get"};
	$secondValue = $values[$i]{"put"};
	} elsif ($values[$i]{"type"} eq "Lexer") {
	$firstValue = $values[$i]{"value"};
	$secondValue = "0";
	}
	print " { \"$key\", $attrs[$i], (intptr_t)$firstValue, (intptr_t)$secondValue },\n";
	$i++;
	}
	print " { 0, 0, 0, 0 }\n";
	print "};\n\n";
	print "extern const struct HashTable $name =\n";
	print " \{ $compactSize, $compactHashSizeMask, $nameEntries, 0 \};\n";
	print "} // namespace\n";
	}