[google][4.7]Port function reordering via linker plugin from google/gcc-4_6 branch (issue6195099)

[Sriraman Tallam]

Patch too large to be attached, rejected by gcc-patches. Please see:

http://codereview.appspot.com/download/issue6195099_1.diff

Thanks,
-Sri.

On Wed, May 16, 2012 at 6:52 PM, Sriraman Tallam <tmsriram@google.com> wrote:
> Hi,
>
>  This patch ports function reordering support into google/gcc-4_7 branch
>  from google/gcc-4_6 branch.  There are 3 parts which are combined:
>
>  * Adding option -freoder-functions=callgraph.
>  * Dumping callgraph profiles in separate sections.
>  * The linker plugin itself.
>
>  Port revisions from google/gcc-4_6
>  r177289, r177308, r179104, r179289, r179303, r179404, r182447
>
>  into google/gcc-4_7
>
>  adding function reordering support via linker plugin invoked with option
>  -freorder-functions=callgraph.
>
> Patch also can be reviewed here: http://codereview.appspot.com/6195099
>
> function_reordering_plugin:
>
>       * config.h.in: Generate.
>       * configure: Generate.
>       * Makefile.in: New file.
>       * configure.ac: New file.
>       * callgraph.h: New file.
>       * callgraph.c: New file.
>       * function_reordering_plugin.c: New file.
>       * Makefile.am: Generate.
>       * aclocal.m4: Generate.
>
> gcc:
>       * doc/invoke.texi: Document -freorder-functions=*
>       * cgraphbuild.c (remove_cgraph_callee_edges): Preserve
>       callgraph till pass_final.
>       * configure: Regenerate.
>       * final.c (dump_cgraph_profiles): New function.
>       (rest_of_handle_final): Call dumping of cgraph profiles in
>       .gnu.text.callgraph sections.
>       * gcc.c (LINK_COMMAND_SPEC): Process -freorder-functions=
>       (set_func_reorder_linker_plugin_spec): New function.
>       (main): Call function reorder plugin.
>       * testsuite/lib/target-supports-dg.exp
>       (dg-require-section-exclude): New proc.
>       (dg-require-linker-function-reordering-plugin): New proc.
>       * testsuite/lib/target-supports.exp
>       (check_section_exclude_available): New proc.
>       (check_linker_function_reordering_plugin_supported): New proc.
>       * testsuite/g++.dg/tree-prof/callgraph-profiles.C: New test.
>       * config.in: undef FRPLUGINSONAME
>       * opts.c
>       * configure.ac (FRPLUGINSONAME): Define
>       * common.opt (fcallgraph-profiles-sections): Remove.
>       (freorder-functions=): New option.
>       * tree-optimize.c (gate_all_optimizations): Mark last cleanup of
>       callgraph.
>       * config.host: Set function reordering plugin.
>       * params.def (PARAM_NOTE_CGRAPH_SECTION_EDGE_THRESHOLD): Remove.
>       (PARAM_GNU_CGRAPH_SECTION_EDGE_THRESHOLD): Add.
>
> toplevel:
>       * Makefile.in: Regenerate.
>       * Makefile.def: Build function reordering plugin.
>       * configure.ac: Build function reordering plugin.
>       * configure: Regenerate.
>
> Patch attached.
>
> Thanks,
> -Sri.