Re: struct-reorg optimization

[Olga Golovanevsky <OLGA at il dot ibm dot com>]

"Daniel Berlin" <dberlin@dberlin.org> wrote on 20/07/2007 00:22:33:

>
> Comments on struct-reorg.c:
>
>
> 1. The comments in strip_t ype do not make clear what it does
> Just based on looking at it, it should be using POINTER_TYPE_P, not
> TREE_CODE (type) == POINTER_TYPE

done.

> 2. why is get_type_name returning a char * and not a const char *?

changed, done.

> 3. why is get_type_var using DECL_ARG_TYPE?

because get_type_var receives function parameters as arguments as well.

> 4.
>   if (SSA_NAME_IS_DEFAULT_DEF(before_cast))
>     return false;
> Should be
>   if (SSA_NAME_IS_DEFAULT_DEF (before_cast))
>     return false;

fixed.

> 5. your offset/base splitting code seems to be trying to approximate
> exactly what get_ref_and_base_extent will do for you.
>
not exactly, as I need offset/base variables there.

> 6. In build_basic_struct, why are you touching C_* fields?

fixed.

>
> 7. Don't use CONSTANT_CLASS_P and simple_cst_equal, just call
> operand_equal_p on rhs

fixed.

>
> 8. It seems you assume struct sizes fit in unsigned int in a lot of
> places, when they should actually be HOST_WIDE_INT

fixed.

This is an updated patch. In addition to changes mentioned above,
by suggestion of Peter Bergner, I have changes the model to
peel hot fields one by one instead of clustering them. It scales
better, and now we are getting 47% on art with and w/o profiling, i.e.
when by default we completely peel the structure into separate fields.

Any further comments? Ok for mainline?

:ADDPATCH ipa ssa:

Olga

2007-08-01  Olga Golovanevsky  <olga@il.ibm.com>

      * struct-reorg.c, struct-reorg.h: New files.
      * tree.h: Add pass_ipa_struct_reorg.
      * common.opt: Add ipa-struct-reorg flag.
      * Makefile.in: Add strcut-reorg.o compilation.
      * passes.c: Add pass pass_ipa_struct_reorg.

(See attached file: struct-reorg.h)(See attached file: struct_reorg.txt)
(See attached file: struct-reorg.c)

Attachment: struct-reorg.h
Description: Binary data

Attachment: struct_reorg.txt
Description: Text document

Attachment: struct-reorg.c
Description: Binary data