[Bug middle-end/54146] Very slow compile with attribute((flatten))

[steven at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54146

--- Comment #54 from Steven Bosscher <steven at gcc dot gnu.org> 2012-08-17 
09:42:15 UTC ---
Author: steven
Date: Fri Aug 17 09:42:06 2012
New Revision: 190475

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=190475
Log:
    PR middle-end/54146
    * tree-ssa-loop-im.c (lim_bitmap_obstack): New bitmap_obstack.
    (memref_free): Don't free the bitmaps individually here.
    (mem_ref_alloc): Allocate the bitmaps on the new bitmap obstack.
    (analyze_memory_references): Likewise.
    (tree_ssa_lim_initialize): Initialize the new bitmap obstack.
    (tree_ssa_lim_finalize): Release it.
    * dse.c (dse_bitmap_obstack): New bitmap obstack.
    (dse_obstack): New obstack.
    (get_group_info): Allocate the bitmaps on the new bitmap obstack.
    (dse_step0): Allocate the scratch bitmap on reg_obstack.  Initialize
    the new bitmap obstack and normal obstack.  Use XNEWVEC for bb_table.
    (record_store): Allocate regs_set on reg_obstack.
    (dse_step1): Allocate regs_live on reg_obstack.
    (dse_step2_init): Allocate offset_map_n and offset_map_p on the new
    obstack.
    (dse_step3_scan): Allocate bitmaps on the new bitmap obstack.
    (dse_step3): Likewise.
    (dse_confluence_0): Likewise.
    (dse_confluence_n): Likewise.
    (dse_transfer_function): Likewise.
    (dse_step7): Destroy the new obstacks, and everything allocated on
    them, in one big sweep.
    (rest_of_handle_dse): Update.
    * cfgexpand.c (stack_var_bitmap_obstack): New bitmap obstack.
    (add_stack_var_conflict): Allocate bitmaps on it.
    (add_scope_conflicts_1): Likewise.
    (add_scope_conflicts): Likewise.
    (update_alias_info_with_stack_vars): Likewise.
    (init_vars_expansion): Move TREE_USED fiddling expand_used_vars.
    Initialize the new bitmap obstack.
    (fini_vars_expansion): Release it.
    (estimated_stack_frame_size): Use init_vars_expansion to set things up
    and always clean up at the end.
    (expand_used_vars): Do the TREE_USED trickery here.  Always call
    fini_vars_expansion.
    * tree-ssa-live.h (struct tree_live_info_d): Make livein and liveout
    arrays of bitmap_head to avoid one indirection per bitmap access.
    (live_on_entry, live_on_exit, live_var_map, live_merge_and_clear,
    make_live_on_entry): Update.
    * tree-ssa-live.c (partition_view_bitmap): Don't double-free 'used'.
    (liveness_bitmap_obstack): New bitmap obstack.
    (remove_unused_locals): Use it to allocate all bitmaps on.  Update
    for livein/liveout changes in tree-ssa-live.h.
    (delete_tree_live_info): Release the bitmap obstack.
    (loe_visit_block, live_worklist, set_var_live_on_entry,
    calculate_live_on_exit, dump_live_info): Update.
    (calculate_live_ranges): Initialize the bitmap.
    * tree-ssa-ter.c (ter_bitmap_obstack): New bitmap obstack.
    (new_temp_expr_table): Allocate bitmap on it.
    (make_dependent_on_partition, add_to_partition_kill_list,
    add_dependence, process_replaceable): Likewise.
    (find_replaceable_exprs): Initialize and release the new obstack here.
    * df-problems.c (df_lr_add_problem): Allocate persistent bitmap
    for out_of_date_transfer_functions on df_bitmap_obstack.
    (df_live_add_problem): Likewise.
    (df_chain_add_problem): Likewise.
    (df_word_lr_add_problem): Likewise.


Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/cfgexpand.c
    trunk/gcc/df-problems.c
    trunk/gcc/dse.c
    trunk/gcc/tree-ssa-live.c
    trunk/gcc/tree-ssa-live.h
    trunk/gcc/tree-ssa-loop-im.c
    trunk/gcc/tree-ssa-loop-manip.c
    trunk/gcc/tree-ssa-ter.c