+Tue Oct 20 10:59:02 1998 Gavin Romig-Koch <gavin@cygnus.com>
+
+ * regclass.c (fix_register): Add error message.
+ * invoke.texi (-fcall-used-REG,-fcall-saved-REG): Note the
+ new error message.
+
Tue Oct 20 10:12:17 1998 Kaveh R. Ghazi <ghazi@caip.rutgers.edu>
* c-decl.c (warn_missing_noreturn): New global variable.
variables that do not live across a call. Functions compiled this way
will not save and restore the register @var{reg}.
-Use of this flag for a register that has a fixed pervasive role in the
-machine's execution model, such as the stack pointer or frame pointer,
-will produce disastrous results.
+It is an error to used this flag with the frame pointer or stack pointer.
+Use of this flag for other registers that have fixed pervasive roles in
+the machine's execution model will produce disastrous results.
This flag does not have a negative form, because it specifies a
three-way choice.
live across a call. Functions compiled this way will save and restore
the register @var{reg} if they use it.
-Use of this flag for a register that has a fixed pervasive role in the
-machine's execution model, such as the stack pointer or frame pointer,
-will produce disastrous results.
+It is an error to used this flag with the frame pointer or stack pointer.
+Use of this flag for other registers that have fixed pervasive roles in
+the machine's execution model will produce disastrous results.
A different sort of disaster will result from the use of this flag for
a register in which function values may be returned.
if ((i = decode_reg_name (name)) >= 0)
{
- fixed_regs[i] = fixed;
- call_used_regs[i] = call_used;
+ if ((i == STACK_POINTER_REGNUM
+#ifdef HARD_FRAME_POINTER_REGNUM
+ || i == HARD_FRAME_POINTER_REGNUM
+#else
+ || i == FRAME_POINTER_REGNUM
+#endif
+ )
+ && (fixed == 0 || call_used == 0))
+ {
+ static char* what_option[2][2] = {
+ "call-saved", "call-used",
+ "no-such-option", "fixed" };
+
+ error ("can't use '%s' as a %s register", name,
+ what_option[fixed][call_used]);
+ }
+ else
+ {
+ fixed_regs[i] = fixed;
+ call_used_regs[i] = call_used;
+ }
}
else
{