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Date: Mon, 11 Apr 2011 16:30:34 +0100
Message-ID: <BANLkTikcC4TSp+3znAc4yt_O37iY4jUihg@mail.gmail.com>
Subject: Re: [Qemu-devel] Re: [PATCH] target-sh4: get rid of CPU_{Float,
	Double}U
From: Peter Maydell <peter.maydell@linaro.org>
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To: Richard Henderson <rth@twiddle.net>
Cc: Aurelien Jarno <aurelien@aurel32.net>, qemu-devel@nongnu.org, Nathan Froyd <froydnj@codesourcery.com>

On 11 April 2011 16:19, Richard Henderson <rth@twiddle.net> wrote:
> On 04/11/2011 08:09 AM, Peter Maydell wrote:
>> (4) I think you should be able to write a helper function for an
>> add as just
>> =C2=A0float32 HELPER(my_float_add)(float32 a, float32 b) {
>> =C2=A0 =C2=A0 =C2=A0return float32_add(a, b, status);
>> =C2=A0}
>
> While this is a laudable goal, this will fail for hosts that pass
> all structures by reference. =C2=A0This is true of, e.g. PPC32.

...but only if float32 is a struct, which is where we came in.
In the sane default configuration float32 is just a uint32_t
in disguise.

In other words, my point is that I'd prefer to give up[*] being
able to run with float32-is-a-struct rather than give up having
clean and straightforward helper functions.

[*] actually I suspect we've never actually had this capability
so we're not really giving anything up except philosophically...

-- PMM