+Tue Oct 21 10:06:40 1997 Jeffrey A Law (law@cygnus.com)
+
+ * mn10300.c (expand_epilogue): Rework to handle register restores
+ in "ret" and "retf" instructions correctly.
+
Mon Oct 20 16:47:08 1997 Jim Wilson <wilson@cygnus.com>
* expmed.c (extract_bit_field): Don't make flag_force_mem disable
size = get_frame_size () + current_function_outgoing_args_size;
size += (current_function_outgoing_args_size ? 4 : 0);
- /* Cut back the stack. */
+ /* Maybe cut back the stack, except for the register save area.
+
+ If the frame pointer exists, then use the frame pointer to
+ cut back the stack.
+
+ If the stack size + register save area is more than 255 bytes,
+ then the stack must be cut back here since the size + register
+ save size is too big for a ret/retf instruction.
+
+ Else leave it alone, it will be cut back as part of the
+ ret/retf instruction, or there wasn't any stack to begin with.
+
+ Under no circumstanes should the register save area be
+ deallocated here, that would leave a window where an interrupt
+ could occur and trash the register save area. */
if (frame_pointer_needed)
{
emit_move_insn (stack_pointer_rtx, frame_pointer_rtx);
}
else if ((regs_ever_live[2] || regs_ever_live[3]
|| regs_ever_live[6] || regs_ever_live[7])
- && size > 255)
+ && size + 16 > 255)
{
emit_insn (gen_addsi3 (stack_pointer_rtx,
stack_pointer_rtx,
if (regs_ever_live[2] || regs_ever_live[3]
|| regs_ever_live[6] || regs_ever_live[7]
|| frame_pointer_needed)
- emit_jump_insn (gen_return_internal_regs (GEN_INT (size)));
+ emit_jump_insn (gen_return_internal_regs (GEN_INT (size + 16)));
else
{
if (size)