[PATCH] [BZ #19679] [x86_64] Set DL_RUNIME_UNALIGNED_VEC_SIZE to 8

[Florian Weimer]

On 02/20/2016 12:49 AM, H.J. Lu wrote:
> +#ifndef DL_RUNTIME_UNALIGNED_VEC_SIZE
> +/* The maximum size in bytes of unaligned vector load and store in the
> +   dynamic linker.  Since SSE optimized memory/string functions with
> +   aligned SSE register load and store are used in the dynamic linker,
> +   we must set this to 8 so that _dl_runtime_resolve_sse will align the
> +   stack before calling _dl_fixup.  */
> +# define DL_RUNTIME_UNALIGNED_VEC_SIZE 8

The comment doesn't really explain the situation.  If all programs
actually fallowed the psABI, we wouldn't need this.

I think it's easier at this point to change the psABI to say that
__tls_getaddr can be called with an 8-byte-aligned stack.

And DL_RUNTIME_UNALIGNED_VEC_SIZE etc. can be removed.

Florian