Re: [PATCH] LTO: Handle merged option sections

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

On Tue, Jul 27, 2010 at 4:51 PM, Andi Kleen <andi@firstfloor.org> wrote:
> LTO: Handle merged option sections
>
> This closes one small hole in the merged section "ld -r" handling.
> The options section does not have a suffix and can be merged.
> Fix the option reader to loop over all copies of the options.
>
> Passed a bootstrap and full test suite run on x86_64-linux
>
> Ok to commit?

Ok.

Thanks,
RIchard.

> 2010-07-27 ?Andi Kleen <ak@linux.intel.com>
>
> ? ? ? ?* lto-opts.c (lto_file_read_options): Add loop over all inputs.
>
> Index: gcc/lto-opts.c
> ===================================================================
> --- gcc/lto-opts.c ? ? ?(revision 162566)
> +++ gcc/lto-opts.c ? ? ?(working copy)
> @@ -349,8 +349,8 @@
> ?void
> ?lto_read_file_options (struct lto_file_decl_data *file_data)
> ?{
> - ?size_t len;
> - ?const char *data;
> + ?size_t len, l, skip;
> + ?const char *data, *p;
> ? const struct lto_simple_header *header;
> ? int32_t opts_offset;
> ? struct lto_input_block ib;
> @@ -358,14 +358,30 @@
> ? data = lto_get_section_data (file_data, LTO_section_opts, NULL, &len);
> ? if (!data)
> ? ? ? ? ?return;
> - ?header = (const struct lto_simple_header *) data;
> - ?opts_offset = sizeof (*header);
>
> - ?lto_check_version (header->lto_header.major_version,
> - ? ? ? ? ? ? ? ? ? ?header->lto_header.minor_version);
> + ?/* Option could be multiple sections merged (through ld -r)
> + ? ? Keep reading all options. ?This is ok right now because
> + ? ? the options just get mashed together anyways.
> + ? ? This will have to be done differently once lto-opts knows
> + ? ? how to associate options with different files. */
> + ?l = len;
> + ?p = data;
> + ?do
> + ? ?{
> + ? ? ?header = (const struct lto_simple_header *) p;
> + ? ? ?opts_offset = sizeof (*header);
>
> - ?LTO_INIT_INPUT_BLOCK (ib, data + opts_offset, 0, header->main_size);
> - ?input_options (&ib);
> + ? ? ?lto_check_version (header->lto_header.major_version,
> + ? ? ? ? ? ? ? ? ? ? ? ?header->lto_header.minor_version);
> +
> + ? ? ?LTO_INIT_INPUT_BLOCK (ib, p + opts_offset, 0, header->main_size);
> + ? ? ?input_options (&ib);
> +
> + ? ? ?skip = header->main_size + opts_offset;
> + ? ? ?l -= skip;
> + ? ? ?p += skip;
> + ? ?}
> + ?while (l > 0);
>
> ? lto_free_section_data (file_data, LTO_section_opts, 0, data, len);
> ?}
>