-#ifdef FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN
- if (FORCE_PREFERRED_STACK_BOUNDARY_IN_MAIN)
- {
- int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
- rtx tmp, seq;
-
- start_sequence ();
- /* Forcibly align the stack. */
-#ifdef STACK_GROWS_DOWNWARD
- tmp = expand_simple_binop (Pmode, AND, stack_pointer_rtx, GEN_INT(-align),
- stack_pointer_rtx, 1, OPTAB_WIDEN);
-#else
- tmp = expand_simple_binop (Pmode, PLUS, stack_pointer_rtx,
- GEN_INT (align - 1), NULL_RTX, 1, OPTAB_WIDEN);
- tmp = expand_simple_binop (Pmode, AND, tmp, GEN_INT (-align),
- stack_pointer_rtx, 1, OPTAB_WIDEN);
-#endif
- if (tmp != stack_pointer_rtx)
- emit_move_insn (stack_pointer_rtx, tmp);
-
- /* Enlist allocate_dynamic_stack_space to pick up the pieces. */
- tmp = force_reg (Pmode, const0_rtx);
- allocate_dynamic_stack_space (tmp, NULL_RTX, BIGGEST_ALIGNMENT);
- seq = get_insns ();
- end_sequence ();
-
- for (tmp = get_last_insn (); tmp; tmp = PREV_INSN (tmp))
- if (NOTE_P (tmp) && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_FUNCTION_BEG)
- break;
- if (tmp)
- emit_insn_before (seq, tmp);
- else
- emit_insn (seq);
- }
-#endif
-