linux-kernel - Re: [PATCH 5/5] modpost: squash if...else if in find_elf

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Message-ID: <CAKwvOdn00NxJo+_SCHcBx2JO0doZQx9cL0TdFDfQAwMOXDMc8w@mail.gmail.com>
Date:   Tue, 24 May 2022 13:51:19 -0700
From:   Nick Desaulniers <ndesaulniers@...gle.com>
To:     Masahiro Yamada <masahiroy@...nel.org>
Cc:     linux-kbuild@...r.kernel.org, linux-kernel@...r.kernel.org,
        Michal Marek <michal.lkml@...kovi.net>
Subject: Re: [PATCH 5/5] modpost: squash if...else if in find_elf_symbol2()

On Mon, May 23, 2022 at 9:48 AM Masahiro Yamada <masahiroy@...nel.org> wrote:
>
>     if ((addr - sym->st_value) < distance) {
>             distance = addr - sym->st_value;
>             near = sym;
>     } else if ((addr - sym->st_value) == distance) {
>             near = sym;
>     }
>
> is equivalent to:
>
>     if ((addr - sym->st_value) <= distance) {
>             distance = addr - sym->st_value;
>             near = sym;
>     }
>
> (The else-if part can overwrite 'distance' with the same value).
>
> Signed-off-by: Masahiro Yamada <masahiroy@...nel.org>

Sure, thanks for the patch!
Reviewed-by: Nick Desaulniers <ndesaulniers@...gle.com>

> ---
>
>  scripts/mod/modpost.c | 10 +++-------
>  1 file changed, 3 insertions(+), 7 deletions(-)
>
> diff --git a/scripts/mod/modpost.c b/scripts/mod/modpost.c
> index 48a18b59f908..8c8d2a4bc0b0 100644
> --- a/scripts/mod/modpost.c
> +++ b/scripts/mod/modpost.c
> @@ -1270,13 +1270,9 @@ static Elf_Sym *find_elf_symbol2(struct elf_info *elf, Elf_Addr addr,
>                         continue;
>                 if (!is_valid_name(elf, sym))
>                         continue;
> -               if (sym->st_value <= addr) {
> -                       if ((addr - sym->st_value) < distance) {
> -                               distance = addr - sym->st_value;
> -                               near = sym;
> -                       } else if ((addr - sym->st_value) == distance) {
> -                               near = sym;
> -                       }
> +               if (sym->st_value <= addr && addr - sym->st_value <= distance) {
> +                       distance = addr - sym->st_value;
> +                       near = sym;
>                 }
>         }
>         return near;
> --
> 2.32.0
>


-- 
Thanks,
~Nick Desaulniers