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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);
+}