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diff --git a/locale/coll-lookup.h b/locale/coll-lookup.h
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+/* Copyright (C) 2000 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Bruno Haible <haible@clisp.cons.org>, 2000.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   The GNU C 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+/* Word tables are accessed by cutting wc in three blocks of bits:
+   - the high 32-q-p bits,
+   - the next q bits,
+   - the next p bits.
+
+	    +------------------+-----+-----+
+     wc  =  +      32-q-p      |  q  |  p  |
+	    +------------------+-----+-----+
+
+   p and q are variable.  For 16-bit Unicode it is sufficient to
+   choose p and q such that q+p <= 16.
+
+   The table contains the following uint32_t words:
+   - q+p,
+   - s = upper exclusive bound for wc >> (q+p),
+   - p,
+   - 2^q-1,
+   - 2^p-1,
+   - 1st-level table: s offsets, pointing into the 2nd-level table,
+   - 2nd-level table: k*2^q offsets, pointing into the 3rd-level table,
+   - 3rd-level table: j*2^p words, each containing 32 bits of data.
+*/
+
+#include <stdint.h>
+
+/* Lookup in a table of int32_t, with default value 0.  */
+static inline int32_t
+collidx_table_lookup (const char *table, uint32_t wc)
+{
+  uint32_t shift1 = ((const uint32_t *) table)[0];
+  uint32_t index1 = wc >> shift1;
+  uint32_t bound = ((const uint32_t *) table)[1];
+  if (index1 < bound)
+    {
+      uint32_t lookup1 = ((const uint32_t *) table)[5 + index1];
+      if (lookup1 != 0)
+	{
+	  uint32_t shift2 = ((const uint32_t *) table)[2];
+	  uint32_t mask2 = ((const uint32_t *) table)[3];
+	  uint32_t index2 = (wc >> shift2) & mask2;
+	  uint32_t lookup2 = ((const uint32_t *)(table + lookup1))[index2];
+	  if (lookup2 != 0)
+	    {
+	      uint32_t mask3 = ((const uint32_t *) table)[4];
+	      uint32_t index3 = wc & mask3;
+	      int32_t lookup3 = ((const int32_t *)(table + lookup2))[index3];
+
+	      return lookup3;
+	    }
+	}
+    }
+  return 0;
+}
+
+/* Lookup in a table of uint32_t, with default value 0xffffffff.  */
+static inline uint32_t
+collseq_table_lookup (const char *table, uint32_t wc)
+{
+  uint32_t shift1 = ((const uint32_t *) table)[0];
+  uint32_t index1 = wc >> shift1;
+  uint32_t bound = ((const uint32_t *) table)[1];
+  if (index1 < bound)
+    {
+      uint32_t lookup1 = ((const uint32_t *) table)[5 + index1];
+      if (lookup1 != 0)
+	{
+	  uint32_t shift2 = ((const uint32_t *) table)[2];
+	  uint32_t mask2 = ((const uint32_t *) table)[3];
+	  uint32_t index2 = (wc >> shift2) & mask2;
+	  uint32_t lookup2 = ((const uint32_t *)(table + lookup1))[index2];
+	  if (lookup2 != 0)
+	    {
+	      uint32_t mask3 = ((const uint32_t *) table)[4];
+	      uint32_t index3 = wc & mask3;
+	      uint32_t lookup3 = ((const uint32_t *)(table + lookup2))[index3];
+
+	      return lookup3;
+	    }
+	}
+    }
+  return ~((uint32_t) 0);
+}