[PATCH v1 1/6] elf: Refactor dl_new_hash so it can be tested / benchmarked

[H.J. Lu]

On Wed, Apr 13, 2022 at 9:12 PM Noah Goldstein <goldstein.w.n@gmail.com> wrote:
>
> No change to the code other than moving it to
> sysdeps/generic/dl-hash.h. Changed name so its now in the
> reserved namespace.
> ---
>  sysdeps/generic/dl-hash.h   | 13 +++++++++++++
>  sysdeps/i386/i686/dl-hash.h |  3 +++
>  2 files changed, 16 insertions(+)
>
> diff --git a/sysdeps/generic/dl-hash.h b/sysdeps/generic/dl-hash.h
> index 9bc7e3bd67..c041074352 100644
> --- a/sysdeps/generic/dl-hash.h
> +++ b/sysdeps/generic/dl-hash.h
> @@ -19,7 +19,9 @@
>  #ifndef _DL_HASH_H
>  #define _DL_HASH_H     1
>
> +#include <stdint.h>
>
> +#ifndef __HAS_DL_ELF_HASH
>  /* This is the hashing function specified by the ELF ABI.  In the
>     first five operations no overflow is possible so we optimized it a
>     bit.  */
> @@ -71,5 +73,16 @@ _dl_elf_hash (const char *name_arg)
>      }
>    return hash;
>  }
> +#endif /* !__HAS_DL_ELF_HASH */
> +
> +static uint32_t
> +__dl_new_hash (const char *s)

I think this should be put in a new header file, dl-new-hash.h, and rename
the function to _dl_new_hash.

> +{
> +  uint32_t h = 5381;
> +  for (unsigned char c = *s; c != '\0'; c = *++s)
> +    h = h * 33 + c;
> +  return h;
> +}
> +
>
>  #endif /* dl-hash.h */
> diff --git a/sysdeps/i386/i686/dl-hash.h b/sysdeps/i386/i686/dl-hash.h
> index c124480e77..d18370350d 100644
> --- a/sysdeps/i386/i686/dl-hash.h
> +++ b/sysdeps/i386/i686/dl-hash.h
> @@ -75,4 +75,7 @@ _dl_elf_hash (const char *name)
>    return result;
>  }
>
> +#define __HAS_DL_ELF_HASH      1
> +#include <sysdeps/generic/dl-hash.h>
> +
>  #endif /* dl-hash.h */
> --
> 2.25.1
>


-- 
H.J.