https://gcc.gnu.org/bugzilla/show_bug.cgi?id=104558
--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
It is the
- emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
- parm_align, partial, reg, excess, argblock,
- ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
- ARGS_SIZE_RTX (arg->locate.alignment_pad), false);
+ if (!CONST_INT_P (size_rtx) || INTVAL (size_rtx) != 0)
+ emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), size_rtx,
+ parm_align, partial, reg, excess, argblock,
+ ARGS_SIZE_RTX (arg->locate.offset),
+ reg_parm_stack_space,
+ ARGS_SIZE_RTX (arg->locate.alignment_pad), false);
change that breaks this. While we don't really need to push anything when
size_rtx is const0_rtx, emit_push_insn at the end does:
if (alignment_pad && args_addr == 0)
anti_adjust_stack (alignment_pad);
so I wonder if we don't need:
else if (maybe_ne (arg->locate.alignment_pad, 0)
&& argblock == NULL_RTX)
anti_adjust_stack (ARGS_SIZE_RTX (arg->locate.alignment_pad));
or so (also in the other spot).
