diff -r 000000000000 -r 6474c204b198 js/src/vm/make_unicode.py
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/vm/make_unicode.py	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,377 @@
+# -*- coding: utf-8 -*-
+# Based upon makeunicodedata.py
+# (http://hg.python.org/cpython/file/c8192197d23d/Tools/unicode/makeunicodedata.py)
+# written by Fredrik Lundh (fredrik@pythonware.com)
+#
+#    Copyright (C) 2011 Tom Schuster <evilpies@gmail.com>
+#
+#    This program is free software: you can redistribute it and/or modify
+#    it under the terms of the GNU General Public License as published by
+#    the Free Software Foundation, either version 3 of the License, or
+#    (at your option) any later version.
+#
+#    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.
+#
+#    You should have received a copy of the GNU General Public License
+#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+from __future__ import print_function
+import csv
+import sys
+
+# ECMAScript 5 $ 7.2
+whitespace = [
+    # python doesn't support using control character names :(
+    0x9, # CHARACTER TABULATION
+    0xb, # LINE TABULATION
+    0xc, # FORM FEED
+    ord(u'\N{SPACE}'),
+    ord(u'\N{NO-BREAK SPACE}'),
+    ord(u'\N{ZERO WIDTH NO-BREAK SPACE}'), # also BOM
+]
+
+# $ 7.3
+line_terminator = [
+    0xa, # LINE FEED
+    0xd, # CARRIAGE RETURN
+    ord(u'\N{LINE SEPARATOR}'),
+    ord(u'\N{PARAGRAPH SEPARATOR}'),
+]
+
+# These are also part of IdentifierPart $7.6
+ZWNJ = ord(u'\N{ZERO WIDTH NON-JOINER}')
+ZWJ = ord(u'\N{ZERO WIDTH JOINER}')
+
+FLAG_SPACE = 1 << 0
+FLAG_LETTER = 1 << 1
+FLAG_IDENTIFIER_PART = 1 << 2
+
+MAX = 0xffff
+
+public_domain = """
+/*
+ * Any copyright is dedicated to the Public Domain.
+ * http://creativecommons.org/licenses/publicdomain/
+ */
+"""
+
+def read_unicode_data(unicode_file):
+    """
+        If you want to understand how this wonderful file format works checkout
+          Unicode Standard Annex #44 - Unicode Character Database
+          http://www.unicode.org/reports/tr44/
+    """
+
+    reader = csv.reader(unicode_data, delimiter=';')
+
+    while True:
+        row = reader.next()
+        name = row[1]
+
+        # We need to expand the UAX #44 4.2.3 Code Point Range
+        if name.startswith('<') and name.endswith('First>'):
+            next_row = reader.next()
+
+            for i in range(int(row[0], 16), int(next_row[0], 16) + 1):
+                row[0] = i
+                row[1] = name[1:-8]
+
+                yield row
+        else:
+            row[0] = int(row[0], 16)
+            yield row
+
+def generate_unicode_stuff(unicode_data, data_file, test_mapping, test_space):
+    dummy = (0, 0, 0)
+    table = [dummy]
+    cache = {dummy: 0}
+    index = [0] * (MAX + 1)
+    test_table = {}
+    test_space_table = []
+
+    for row in read_unicode_data(unicode_data):
+        code = row[0]
+        name = row[1]
+        category = row[2]
+        alias = row[-5]
+        uppercase = row[-3]
+        lowercase = row[-2]
+        flags = 0
+
+        if code > MAX:
+            break
+
+        # we combine whitespace and lineterminators because in pratice we don't need them separated
+        if category == 'Zs' or code in whitespace or code in line_terminator:
+            flags |= FLAG_SPACE
+            test_space_table.append(code)
+        if category in ['Lu', 'Ll', 'Lt', 'Lm', 'Lo', 'Nl']: # $ 7.6 (UnicodeLetter)
+            flags |= FLAG_LETTER
+        if category in ['Mn', 'Mc', 'Nd', 'Pc'] or code == ZWNJ or code == ZWJ: # $ 7.6 (IdentifierPart)
+            flags |= FLAG_IDENTIFIER_PART
+
+        if uppercase:
+            upper = int(uppercase, 16)
+        else:
+            upper = code
+
+        if lowercase:
+            lower = int(lowercase, 16)
+        else:
+            lower = code
+
+        test_table[code] = (upper, lower, name, alias)
+
+        up_d = upper - code
+        low_d = lower - code
+
+        assert up_d > -65535 and up_d < 65535
+        assert low_d > -65535 and low_d < 65535
+
+        upper = up_d & 0xffff
+        lower = low_d & 0xffff
+
+        item = (upper, lower, flags)
+
+        i = cache.get(item)
+        if i is None:
+            assert item not in table
+            cache[item] = i = len(table)
+            table.append(item)
+        index[code] = i
+
+    test_mapping.write('/* Generated by make_unicode.py DO NOT MODIFY */\n')
+    test_mapping.write(public_domain)
+    test_mapping.write('var mapping = [\n')
+    for code in range(0, MAX + 1):
+        entry = test_table.get(code)
+
+        if entry:
+            upper, lower, name, alias = entry
+            test_mapping.write('  [' + hex(upper) + ', ' + hex(lower) + '], /* ' +
+                       name + (' (' + alias + ')' if alias else '') + ' */\n')
+        else:
+            test_mapping.write('  [' + hex(code) + ', ' + hex(code) + '],\n')
+    test_mapping.write('];')
+    test_mapping.write("""
+assertEq(mapping.length, 0x10000);
+for (var i = 0; i <= 0xffff; i++) {
+    var char = String.fromCharCode(i);
+    var info = mapping[i];
+
+    assertEq(char.toUpperCase().charCodeAt(0), info[0]);
+    assertEq(char.toLowerCase().charCodeAt(0), info[1]);
+}
+
+if (typeof reportCompare === "function")
+    reportCompare(true, true);
+""")
+
+    test_space.write('/* Generated by make_unicode.py DO NOT MODIFY */\n')
+    test_space.write(public_domain)
+    test_space.write('var onlySpace = String.fromCharCode(' +
+                     ', '.join(map(lambda c: hex(c), test_space_table)) + ');\n')
+    test_space.write("""
+assertEq(onlySpace.trim(), "");
+assertEq((onlySpace + 'aaaa').trim(), 'aaaa');
+assertEq(('aaaa' + onlySpace).trim(), 'aaaa');
+assertEq((onlySpace + 'aaaa' + onlySpace).trim(), 'aaaa');
+
+if (typeof reportCompare === "function")
+    reportCompare(true, true);
+""")
+
+    index1, index2, shift = splitbins(index)
+
+    # Don't forget to update CharInfo in Unicode.cpp if you need to change this
+    assert shift == 5
+
+    # verify correctness
+    for char in index:
+        test = table[index[char]]
+
+        idx = index1[char >> shift]
+        idx = index2[(idx << shift) + (char & ((1 << shift) - 1))]
+
+        assert test == table[idx]
+
+
+    comment = """
+/*
+ * So how does indexing work?
+ * First let's have a look at a jschar, 16-bits:
+ *              [................]
+ * Step 1:
+ *  Extracting the upper 11 bits from the jschar.
+ *   upper = char >>  5 ([***********.....])
+ * Step 2:
+ *  Using these bits to get an reduced index from index1.
+ *   index = index1[upper]
+ * Step 3:
+ *  Combining the index and the bottom 5 bits of the original jschar.
+ *   real_index = index2[(index << 5) + (char & ((1 << 5) - 1))] ([...********+++++])
+ *
+ * The advantage here is that the biggest number in index1 doesn't need 10 bits,
+ * but 7 and we save some memory.
+ *
+ * Step 4:
+ *  Get the character informations by looking up real_index in js_charinfo.
+ *
+ * Pseudocode of generation:
+ *
+ * let table be the mapping of jschar => js_charinfo_index
+ * let index1 be an empty array
+ * let index2 be an empty array
+ * let cache be a hash map
+ *
+ * while shift is less then maximal amount you can shift 0xffff before it's 0
+ *  let chunks be table split in chunks of size 2**shift
+ *
+ *  for every chunk in chunks
+ *   if chunk is in cache
+ *    let index be cache[chunk]
+ *   else
+ *    let index be the max key of index2 + 1
+ *    for element in chunk
+ *     push element to index2
+ *    put index as chunk in cache
+ *
+ *   push index >> shift to index1
+ *
+ *  increase shift
+ *  stop if you found the best shift
+ */
+"""
+    data_file.write('/* Generated by make_unicode.py DO NOT MODIFY */\n')
+    data_file.write(public_domain)
+    data_file.write('#include "vm/Unicode.h"\n\n')
+    data_file.write('using namespace js;\n')
+    data_file.write('using namespace js::unicode;\n')
+    data_file.write(comment)
+    data_file.write('const CharacterInfo unicode::js_charinfo[] = {\n')
+    for d in table:
+        data_file.write('    {')
+        data_file.write(', '.join((str(e) for e in d)))
+        data_file.write('},\n')
+    data_file.write('};\n')
+    data_file.write('\n')
+
+    def dump(data, name, file):
+        file.write('const uint8_t unicode::' + name + '[] = {\n')
+
+        line = pad = ' ' * 4
+        lines = []
+        for entry in data:
+            assert entry < 256
+            s = str(entry)
+            s = s.rjust(3)
+
+            if len(line + s) + 5 > 99:
+                lines.append(line.rstrip())
+                line = pad + s + ', '
+            else:
+                line = line + s + ', '
+        lines.append(line.rstrip())
+
+        file.write('\n'.join(lines))
+        file.write('\n};\n')
+
+    dump(index1, 'index1', data_file)
+    data_file.write('\n')
+    dump(index2, 'index2', data_file)
+    data_file.write('\n')
+
+    data_file.write('\n')
+
+def getsize(data):
+    """ return smallest possible integer size for the given array """
+    maxdata = max(data)
+    assert maxdata < 2**32
+
+    if maxdata < 256:
+        return 1
+    elif maxdata < 65536:
+        return 2
+    else:
+        return 4
+
+def splitbins(t):
+    """t -> (t1, t2, shift).  Split a table to save space.
+
+    t is a sequence of ints.  This function can be useful to save space if
+    many of the ints are the same.  t1 and t2 are lists of ints, and shift
+    is an int, chosen to minimize the combined size of t1 and t2 (in C
+    code), and where for each i in range(len(t)),
+        t[i] == t2[(t1[i >> shift] << shift) + (i & mask)]
+    where mask is a bitmask isolating the last "shift" bits.
+    """
+
+    def dump(t1, t2, shift, bytes):
+        print("%d+%d bins at shift %d; %d bytes" % (
+            len(t1), len(t2), shift, bytes), file=sys.stderr)
+        print("Size of original table:", len(t)*getsize(t), \
+            "bytes", file=sys.stderr)
+    n = len(t)-1    # last valid index
+    maxshift = 0    # the most we can shift n and still have something left
+    if n > 0:
+        while n >> 1:
+            n >>= 1
+            maxshift += 1
+    del n
+    bytes = sys.maxsize  # smallest total size so far
+    t = tuple(t)    # so slices can be dict keys
+    for shift in range(maxshift + 1):
+        t1 = []
+        t2 = []
+        size = 2**shift
+        bincache = {}
+
+        for i in range(0, len(t), size):
+            bin = t[i:i + size]
+
+            index = bincache.get(bin)
+            if index is None:
+                index = len(t2)
+                bincache[bin] = index
+                t2.extend(bin)
+            t1.append(index >> shift)
+
+        # determine memory size
+        b = len(t1) * getsize(t1) + len(t2) * getsize(t2)
+        if b < bytes:
+            best = t1, t2, shift
+            bytes = b
+    t1, t2, shift = best
+
+    print("Best:", end=' ', file=sys.stderr)
+    dump(t1, t2, shift, bytes)
+
+    # exhaustively verify that the decomposition is correct
+    mask = 2**shift - 1
+    for i in range(len(t)):
+        assert t[i] == t2[(t1[i >> shift] << shift) + (i & mask)]
+    return best
+
+if __name__ == '__main__':
+    import urllib2
+
+    if len(sys.argv) > 1:
+        print('Always make sure you have the newest UnicodeData.txt!')
+        unicode_data = open(sys.argv[1], 'r')
+    else:
+        print('Downloading...')
+        reader = urllib2.urlopen('http://unicode.org/Public/UNIDATA/UnicodeData.txt')
+        data = reader.read()
+        reader.close()
+        unicode_data = open('UnicodeData.txt', 'w+')
+        unicode_data.write(data)
+        unicode_data.seek(0)
+
+    print('Generating...')
+    generate_unicode_stuff(unicode_data,
+        open('Unicode.cpp', 'w'),
+        open('../tests/ecma_5/String/string-upper-lower-mapping.js', 'w'),
+        open('../tests/ecma_5/String/string-space-trim.js', 'w'))