2 * Derived from arch/ppc/mm/extable.c and arch/i386/mm/extable.c.
4 * Copyright (C) 2004 Paul Mackerras, IBM Corp.
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
14 #include <lwk/extable.h>
16 #ifndef ARCH_HAS_SORT_EXTABLE
18 * The exception table needs to be sorted so that the binary
19 * search that we use to find entries in it works properly.
20 * This is used both for the kernel exception table and for
21 * the exception tables of modules that get loaded.
23 static int cmp_ex(const void *a, const void *b)
25 const struct exception_table_entry *x = a, *y = b;
28 if (x->insn > y->insn)
30 if (x->insn < y->insn)
35 void sort_extable(struct exception_table_entry *start,
36 struct exception_table_entry *finish)
38 sort(start, finish - start, sizeof(struct exception_table_entry),
43 #ifndef ARCH_HAS_SEARCH_EXTABLE
45 * Search one exception table for an entry corresponding to the
46 * given instruction address, and return the address of the entry,
47 * or NULL if none is found.
48 * We use a binary search, and thus we assume that the table is
51 const struct exception_table_entry *
52 search_extable(const struct exception_table_entry *first,
53 const struct exception_table_entry *last,
56 while (first <= last) {
57 const struct exception_table_entry *mid;
59 mid = (last - first) / 2 + first;
61 * careful, the distance between entries can be
64 if (mid->insn < value)
66 else if (mid->insn > value)