Re: Fix compilation time problem in PR middle-end/37448

["Richard Guenther" <richard dot guenther at gmail dot com>]

On Thu, Sep 11, 2008 at 2:19 PM, Jan Hubicka <jh@suse.cz> wrote:
> Hi,
> PR middle-end/37448 makes inliner to spend a lot of time in
> add_lexical_block that walks to the end of long block list.
> Since we don't keep blocksin any particular order, we can just
> insert instead.
> Bootstrapped/regtested i686-linux, OK?

Ok, but insert_lexical block is as unclear as add_lexical_block.
Maybe call it prepend_lexical_block instead.

Thanks,
Richard.

> Honza
>
>        PR middle-end/37448
>        * tree-inline.c (add_lexical_block): Replace with ...
>        (insert_lexical_block): ... insert at begginig.
>        (remap_blocks): Use it and reverse later.
>        (expand_call_inline): Use insert_lexical_block.
> Index: tree-inline.c
> ===================================================================
> *** tree-inline.c       (revision 140271)
> --- tree-inline.c       (working copy)
> *************** static void unsave_expr_1 (tree);
> *** 129,135 ****
>  static tree unsave_r (tree *, int *, void *);
>  static void declare_inline_vars (tree, tree);
>  static void remap_save_expr (tree *, void *, int *);
> ! static void add_lexical_block (tree current_block, tree new_block);
>  static tree copy_decl_to_var (tree, copy_body_data *);
>  static tree copy_result_decl_to_var (tree, copy_body_data *);
>  static tree copy_decl_maybe_to_var (tree, copy_body_data *);
> --- 129,135 ----
>  static tree unsave_r (tree *, int *, void *);
>  static void declare_inline_vars (tree, tree);
>  static void remap_save_expr (tree *, void *, int *);
> ! static void insert_lexical_block (tree current_block, tree new_block);
>  static tree copy_decl_to_var (tree, copy_body_data *);
>  static tree copy_result_decl_to_var (tree, copy_body_data *);
>  static tree copy_decl_maybe_to_var (tree, copy_body_data *);
> *************** remap_blocks (tree block, copy_body_data
> *** 512,518 ****
>    remap_block (&new_tree, id);
>    gcc_assert (new_tree != block);
>    for (t = BLOCK_SUBBLOCKS (block); t ; t = BLOCK_CHAIN (t))
> !     add_lexical_block (new_tree, remap_blocks (t, id));
>    return new_tree;
>  }
>
> --- 512,521 ----
>    remap_block (&new_tree, id);
>    gcc_assert (new_tree != block);
>    for (t = BLOCK_SUBBLOCKS (block); t ; t = BLOCK_CHAIN (t))
> !     insert_lexical_block (new_tree, remap_blocks (t, id));
> !   /* Blocks are in arbitrary order, but make things slightly prettier and do
> !      not swap order when producing a copy.  */
> !   BLOCK_SUBBLOCKS (new_tree) = blocks_nreverse (BLOCK_SUBBLOCKS (new_tree));
>    return new_tree;
>  }
>
> *************** count_insns_seq (gimple_seq seq, eni_wei
> *** 3032,3047 ****
>  /* Install new lexical TREE_BLOCK underneath 'current_block'.  */
>
>  static void
> ! add_lexical_block (tree current_block, tree new_block)
>  {
> !   tree *blk_p;
> !
> !   /* Walk to the last sub-block.  */
> !   for (blk_p = &BLOCK_SUBBLOCKS (current_block);
> !        *blk_p;
> !        blk_p = &BLOCK_CHAIN (*blk_p))
> !     ;
> !   *blk_p = new_block;
>    BLOCK_SUPERCONTEXT (new_block) = current_block;
>  }
>
> --- 3038,3047 ----
>  /* Install new lexical TREE_BLOCK underneath 'current_block'.  */
>
>  static void
> ! insert_lexical_block (tree current_block, tree new_block)
>  {
> !   BLOCK_CHAIN (new_block) = BLOCK_SUBBLOCKS (current_block);
> !   BLOCK_SUBBLOCKS (current_block) = new_block;
>    BLOCK_SUPERCONTEXT (new_block) = current_block;
>  }
>
> *************** expand_call_inline (basic_block bb, gimp
> *** 3222,3228 ****
>    id->block = make_node (BLOCK);
>    BLOCK_ABSTRACT_ORIGIN (id->block) = fn;
>    BLOCK_SOURCE_LOCATION (id->block) = input_location;
> !   add_lexical_block (gimple_block (stmt), id->block);
>
>    /* Local declarations will be replaced by their equivalents in this
>       map.  */
> --- 3222,3228 ----
>    id->block = make_node (BLOCK);
>    BLOCK_ABSTRACT_ORIGIN (id->block) = fn;
>    BLOCK_SOURCE_LOCATION (id->block) = input_location;
> !   insert_lexical_block (gimple_block (stmt), id->block);
>
>    /* Local declarations will be replaced by their equivalents in this
>       map.  */
> *************** expand_call_inline (basic_block bb, gimp
> *** 3248,3254 ****
>    initialize_inlined_parameters (id, stmt, fn, bb);
>
>    if (DECL_INITIAL (fn))
> !     add_lexical_block (id->block, remap_blocks (DECL_INITIAL (fn), id));
>
>    /* Return statements in the function body will be replaced by jumps
>       to the RET_LABEL.  */
> --- 3248,3254 ----
>    initialize_inlined_parameters (id, stmt, fn, bb);
>
>    if (DECL_INITIAL (fn))
> !     insert_lexical_block (id->block, remap_blocks (DECL_INITIAL (fn), id));
>
>    /* Return statements in the function body will be replaced by jumps
>       to the RET_LABEL.  */
>