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Re: [PATCH] Add ifunc memcpy and memmove for aarch64
On Thursday 23 February 2017 05:57 AM, Steve Ellcey wrote:
> Here is a new version of the IFUNC functionality for aarch64. It does
> not include the memcpy changes to use it. I tried to move the cpu
> feature check to later in the start up process so that I could check
> GLRO(dl_hwcap_mask) but it does not seem to be working. I was
> wondering if anyone could look at this and see if I am doing something
> wrong.
>
> If I understand the code correctly, for a dynamically linked program,
> dl_main is going to get called before dl_sysdep_start and dl_main is
> where environment variables are processed and where dl_hwcap_mask
> should be getting set. But when I check dl_hwcap_mask in
> init_cpu_features (called from dl_sysdep_start), it does not seem to
> have changed from its original value that is set in the new
> dl-procinfo.h header file.
dl_sysdep_start calls dl_main, so you've got the order wrong. If you
want init_cpu_features to read dl_hwcap_mask then you'll have to move
the code to read LD_* environment variables earlier. In fact they need
to go into tunables, something I've had in mind for this release.
Do you want me to move the envvars into tunables or would you like to do it?
Siddhesh