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Re: [RFC][AARCH64] TARGET_ATOMIC_ASSIGN_EXPAND_FENV hook


On 2 May 2014 11:06, Marcus Shawcroft <marcus.shawcroft@gmail.com> wrote:

> Kugan, I've not looked at the respin in detail yet, but it has just
> occurred to me that the sequence used here to set FPCR is
> insufficient.  The architecture reference manual requires that any
> write to FPCR must be syncrhronized by a context synchronization
> operation so we need to plant an ISB after the write.   Both the write
> and ISB are likely to be expensive on some implementations so it would
> be good to ensure that both the write and the isb are scheduled
> independently.  IIRC there si

Sorry, incomplete sentence.  I had started to write that IIRC the same
issue did not apply to FPSCR in the ARM patch.  I have doubled checked
and the FPSCR does not have the issue therefore the ARM patch is fine
in this respect.

/Marcus


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