Re: SUN TLS vs. GNU TLS (was Re: ELF TLS ABI vs L4 ABI)

[Espen Skoglund]

[Marcus Brinkmann]
> As ELF TLS is intended to be used via the __thread keyword, access
> to it is done via the language features of the compiler, and can be
> optimized at the compilers leisure.  In particular, GCC can either
> load the thread pointer and use it with normal memory accesses, or
> do all writes through the %gs segment register, or a mixture of
> both.

Sure, *if* gcc does recognize and "optimize" for the GNU ELF TLS
standard, then it may access the TLS through %gs.  I was just assuming
that the gcc folks were sane enough to not do this (which I hope is
true).  This still doesn't get around optimizing all the hardcoded %gs
stuff deep within glibc, though.

        eSk