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From: Robert Millan <rmh@debian.org>
To: "Jayachandran C." <jchandra@freebsd.org>
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Cc: freebsd-mips@freebsd.org
Subject: Re: [PATCH] Retrieval of TLS pointer via RDHWR
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Not interested?

Note this might become mandatory if you ever want to compile
code that uses TLS with recent GCC.

In any case, when executed natively, rdhwr is a speed-up
compared to a sysarch() call.

2010/12/9 Robert Millan <rmh@debian.org>:
> 2010/12/9 Jayachandran C. <jchandra@freebsd.org>:
>> I'm not sure that the freebsd mips toolchain supports the __thread
>> directive yet. =C2=A0Were you able to test this from C?
>
> Yes, but not via __thread. =C2=A0I wrote a small program that sets
> the TLS pointer to an arbitrary value (via MIPS_SET_TLS),
> then issued rdhwr instruction using C inline assembly, and
> finally verified that both values are the same.
>
> (the toolchain I'm using doesn't support __thread either,
> but I submit this patch with the expectation that it can be
> useful later on)
>
> --
> Robert Millan
>



--=20
Robert Millan