(reg_names): Make it static. Use DEBUG_REGISTER_NAMES if that's defined.

(reg_names): Make it static.  Use DEBUG_REGISTER_NAMES if that's defined.

(DEBUG_PRINT_REG): Define if not defined.
(print_rtx): Use DEBUG_PRINT_REG for hard regs.

(reg_name): Moved here.
Get rid of RCS headers.  Fix up whitespace and comments.
Make key field and corresponding args `const void *'.
Don't use assert.
Get rid of spurious array-level in node_table field; make it void **.
Declare module_hash_table, class_hash_table.
(hash_int): Divide by sizeof (void *), not by 2**that minus 1.

From-SVN: r2455