Re: struct function cleanup part I

["H.J. Lu" <hjl dot tools at gmail dot com>]

Hi,

This patch breaks Linux/ia64:

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=35781

H.J.
On Mon, Mar 31, 2008 at 5:49 AM, Jan Hubicka <jh@suse.cz> wrote:
> Hi,
>  for the PM and cgraph datastructure changes I would like to push out, I need to
>  reorganize data we save in struct function, cgraph_node and other
>  datastructures.  Those datastructures have different lifetimes and usually a
>  lot longer one than data stored in them.
>
>  This patch takes the "easy" part of splitting out RTL data into its own
>  global object. This save memory by making struct function smaller and
>  makes it possible to access the fields directly instead of double
>  indirection.
>
>  Those was originally part of struct function because we maintained in
>  memory multiple functions in RTL form for RTL inlining.  We don't do
>  that anymore and even if we decided to do that again (perhaps for
>  interprocedural regalloc or threaded compiler), we would want to have
>  all the data move off the basic struct function as they consume
>  considerable amount of memory.  I've introduced global "rtl" field that
>  is storing all the associated RTL datastructures instead of having many
>  global variables that looks uglier too.
>
>  This is intended to be first patch followed by more stuff.  I took only fields
>  that are clearly living only for RTL and that do have accestor macros so the patch
>  is not terribly noisy.  Doing so enabled some cleanups and removal of cfun arguments
>  we pass over various old API.
>
>  There is one problem with regno_reg_rtx.  For some reason, gcov_type is not
>  able to handle "length" attributes that are part of global structure fields. I spent
>  quite some time trying to get it working right, but it is challenging.  It seems
>  better to move this datastructure to vector API in one of followup patches.
>  In meantime, I've simply placed it as global array.
>
>  Bootstrapped/regtested i686-linux with more related changes, I am re-testing on
>  clean tree. OK if it passes?
>
>         * builtins.c (expand_builtin_setjmp_receiver): Update call of
>         get_arg_pointer_save_area.
>         * expr.c (init_expr): Just clear out rtl.expr.
>         * function.c (free_after_compilation): Clear out whole RTL structure.
>         (get_func_frame_size): Merge into ...
>         (get_frame_size): ... this one.
>         (assign_stack_local_1): Merge into ...
>         (assign_stack_local): ... this one.
>         (expand_function_end): Update call of get_arg_pointer_save_area.
>         (get_art_pointer_save_area): Remove cfun argument.
>         * function.h (emit_status): regno_pointer_align does not need length
>         attribute. Move x_regno_reg_rtx to ...
>         (regno_reg_rtx): ... new global array.
>         (reg_rtx_no, seq_stack, REGNO_POINTER_ALIGN): Update accestors.
>         (pending_stack_adjust, inhibit_defer_pop, saveregs_value,
>         apply_args_value, forced_labels, stack_pointer_delta): Update accestors.
>         (struct varasm_status): Move here from varasm.c
>         (struct rtl_data): New. Move here some fields from struct function.
>         (return_label, naked_return_label, stack_slot_list, parm_birth_insn,
>         frame_offset, stack_check_probe_note, arg_pointer_save_area,
>         used_temp_slots avail_temp_slots, temp_slot_level,
>         nonlocal_goto_handler_labels): Update accesstors.
>         (rtl): New global variable.
>         (struct function): Move some fileds to rtl_data.
>         (get_arg_pointer_save_area): Update prototype.
>         * emit-rtl.c (rtl): Declare.
>         (regno_reg_rtx): Declare.
>         (first_insn, last_insn, cur_insn_uid, last_location, first_label_num): Update.
>         (gen_reg_rtx): Update.
>         (init_virtual_regs): Do not tate emit_status argument.
>         (init_emit): Do not allocate emit.
>         * varasm.c (varasm_statuc): Move to function.h.
>         (n_deferred_constatns): Update accestor.
>         (init_varasm_status): Do not allocate varasm_status.
>         (force_const_mem, get_pool_size, output_constant_pool): Update.
>         * stmt.c (force_label_rtx): Do not use x_ prefixes.
>         (expand_nl_goto_receiver): Update get_arg_pointer_save_area.