*
* Usage: nm -n vmlinux | scripts/kallsyms [--all-symbols] > symbols.S
*
- * ChangeLog:
- *
- * (25/Aug/2004) Paulo Marques <pmarques@grupopie.com>
- * Changed the compression method from stem compression to "table lookup"
- * compression
- *
* Table compression uses all the unused char codes on the symbols and
* maps these to the most used substrings (tokens). For instance, it might
* map char code 0xF7 to represent "write_" and then in every symbol where
#define KSYM_NAME_LEN 128
-
struct sym_entry {
unsigned long long addr;
unsigned int len;
+ unsigned int start_pos;
unsigned char *sym;
};
-
static struct sym_entry *table;
static unsigned int table_size, table_cnt;
static unsigned long long _text, _stext, _etext, _sinittext, _einittext;
/* exclude also MIPS ELF local symbols ($L123 instead of .L123) */
else if (str[0] == '$')
return -1;
+ /* exclude debugging symbols */
+ else if (stype == 'N')
+ return -1;
/* include the type field in the symbol name, so that it gets
* compressed together */
exit (1);
}
}
- if (read_symbol(in, &table[table_cnt]) == 0)
+ if (read_symbol(in, &table[table_cnt]) == 0) {
+ table[table_cnt].start_pos = table_cnt;
table_cnt++;
+ }
}
}
optimize_result();
}
+/* guess for "linker script provide" symbol */
+static int may_be_linker_script_provide_symbol(const struct sym_entry *se)
+{
+ const char *symbol = (char *)se->sym + 1;
+ int len = se->len - 1;
+
+ if (len < 8)
+ return 0;
+
+ if (symbol[0] != '_' || symbol[1] != '_')
+ return 0;
+
+ /* __start_XXXXX */
+ if (!memcmp(symbol + 2, "start_", 6))
+ return 1;
+
+ /* __stop_XXXXX */
+ if (!memcmp(symbol + 2, "stop_", 5))
+ return 1;
+
+ /* __end_XXXXX */
+ if (!memcmp(symbol + 2, "end_", 4))
+ return 1;
+
+ /* __XXXXX_start */
+ if (!memcmp(symbol + len - 6, "_start", 6))
+ return 1;
+
+ /* __XXXXX_end */
+ if (!memcmp(symbol + len - 4, "_end", 4))
+ return 1;
+
+ return 0;
+}
+
+static int prefix_underscores_count(const char *str)
+{
+ const char *tail = str;
+
+ while (*tail != '_')
+ tail++;
+
+ return tail - str;
+}
+
+static int compare_symbols(const void *a, const void *b)
+{
+ const struct sym_entry *sa;
+ const struct sym_entry *sb;
+ int wa, wb;
+
+ sa = a;
+ sb = b;
+
+ /* sort by address first */
+ if (sa->addr > sb->addr)
+ return 1;
+ if (sa->addr < sb->addr)
+ return -1;
+
+ /* sort by "weakness" type */
+ wa = (sa->sym[0] == 'w') || (sa->sym[0] == 'W');
+ wb = (sb->sym[0] == 'w') || (sb->sym[0] == 'W');
+ if (wa != wb)
+ return wa - wb;
+
+ /* sort by "linker script provide" type */
+ wa = may_be_linker_script_provide_symbol(sa);
+ wb = may_be_linker_script_provide_symbol(sb);
+ if (wa != wb)
+ return wa - wb;
+
+ /* sort by the number of prefix underscores */
+ wa = prefix_underscores_count((const char *)sa->sym + 1);
+ wb = prefix_underscores_count((const char *)sb->sym + 1);
+ if (wa != wb)
+ return wa - wb;
+
+ /* sort by initial order, so that other symbols are left undisturbed */
+ return sa->start_pos - sb->start_pos;
+}
+
+static void sort_symbols(void)
+{
+ qsort(table, table_cnt, sizeof(struct sym_entry), compare_symbols);
+}
int main(int argc, char **argv)
{
usage();
read_map(stdin);
+ sort_symbols();
optimize_token_table();
write_src();