[PATCH] riscv: Cache the max alignment of output sections

[Andrew Waterman]

LGTM, thanks.

On Mon, Oct 9, 2017 at 6:53 PM, H.J. Lu <hjl.tools@gmail.com> wrote:
> Cache the max alignment of output sections instead of scanning all
> output sections for each input section, which can take a very long
> time if there are millions of input/output sections.
>
> OK for master?
>
> H.J.
> ---
>         PR ld/22274
>         * elfnn-riscv.c (riscv_elf_link_hash_table): Add max_alignment.
>         (riscv_elf_link_hash_table_create): Initialize max_alignment to
>         (bfd_vma) -1.
>         (_bfd_riscv_relax_section): Cache the max alignment of output
>         sections if possible.
> ---
>  bfd/elfnn-riscv.c | 16 +++++++++++++++-
>  1 file changed, 15 insertions(+), 1 deletion(-)
>
> diff --git a/bfd/elfnn-riscv.c b/bfd/elfnn-riscv.c
> index 59964ba163..d28cabded5 100644
> --- a/bfd/elfnn-riscv.c
> +++ b/bfd/elfnn-riscv.c
> @@ -127,6 +127,9 @@ struct riscv_elf_link_hash_table
>
>    /* Small local sym to section mapping cache.  */
>    struct sym_cache sym_cache;
> +
> +  /* The max alignment of output sections.  */
> +  bfd_vma max_alignment;
>  };
>
>
> @@ -274,6 +277,7 @@ riscv_elf_link_hash_table_create (bfd *abfd)
>        return NULL;
>      }
>
> +  ret->max_alignment = (bfd_vma) -1;
>    return &ret->elf.root;
>  }
>
> @@ -2976,7 +2980,17 @@ _bfd_riscv_relax_section (bfd *abfd, asection *sec,
>                                                  info->keep_memory)))
>      goto fail;
>
> -  max_alignment = _bfd_riscv_get_max_alignment (sec);
> +  if (htab)
> +    {
> +      max_alignment = htab->max_alignment;
> +      if (max_alignment == (bfd_vma) -1)
> +       {
> +         max_alignment = _bfd_riscv_get_max_alignment (sec);
> +         htab->max_alignment = max_alignment;
> +       }
> +    }
> +  else
> +    max_alignment = _bfd_riscv_get_max_alignment (sec);
>
>    /* Examine and consider relaxing each reloc.  */
>    for (i = 0; i < sec->reloc_count; i++)
> --
> 2.13.6
>