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Date: Wed, 01 Dec 2010 09:52:13 -0800
From: Richard Henderson <rth@twiddle.net>
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Subject: Re: [Qemu-devel] [PATCH 08/12] ARM: Return correct result
	for	single<->double conversion of NaN
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To: Nathan Froyd <froydnj@codesourcery.com>
Cc: Peter Maydell <peter.maydell@linaro.org>, qemu-devel@nongnu.org

On 12/01/2010 07:39 AM, Nathan Froyd wrote:
> RTH (CC'd) is the expert on the Alpha bits.

The Alpha cmptun is supposed to return true for both Q+SNaN.

Although, Invalid Operand is supposed to be raised for SNaN,
which is not happening here in helper_cmptun.  Or, indeed,
any of the comparison helper functions.

I think I've lost the thread a bit -- is the proposal to
replace the existing float*_is_nan with _is_quiet_nan and
invent a new function that returns true for both Q+S?  That
at least would be monotonic improvement for Alpha, although
as noted above not 100% correct.


r~