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From: Peter Maydell <peter.maydell@linaro.org>
Date: Mon, 20 Aug 2018 18:15:07 +0100
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Subject: Re: [Qemu-devel] [PATCH 0/4] target/arm: Fix int64_to_float16
 double-rounding
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To: Richard Henderson <richard.henderson@linaro.org>
Cc: QEMU Developers <qemu-devel@nongnu.org>, Laurent Desnogues <laurent.desnogues@gmail.com>, =?UTF-8?B?QWxleCBCZW5uw6ll?= <alex.bennee@linaro.org>

On 14 August 2018 at 01:26, Richard Henderson
<richard.henderson@linaro.org> wrote:
> In 88808a022c0, I tried to fix an overflow problem that affected float16
> scaling by coverting first to float64 and then rounding after that.
>
> However, Laurent reported that -0x3ff40000000001 converted to float16
> resulted in 0xfbfe instead of the expected 0xfbff.  This is caused by
> the inexact conversion to float64.
>
> Rather than build more logic into target/arm to compensate, just add
> a function that takes a scaling parameter so that the whole thing is
> done all at once with only one rounding.
>
> I don't have a failing test case for the float-to-int paths, but it
> seemed best to apply the same solution.
>
>
> r~
>
>
> Richard Henderson (4):
>   softfloat: Add scaling int-to-float routines
>   softfloat: Add scaling float-to-int routines
>   target/arm: Use the int-to-float-scale softfloat routines
>   target/arm: Use the float-to-int-scale softfloat routines

series
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>

and applied to target-arm.next.

thanks
-- PMM