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From: Alex =?utf-8?Q?Benn=C3=A9e?= <alex.bennee@linaro.org>
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Date: Mon, 29 Jan 2018 11:59:03 +0000
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Subject: Re: [Qemu-devel] [PATCH v3 19/22] fpu/softfloat: re-factor scalbn
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To: Richard Henderson <richard.henderson@linaro.org>
Cc: peter.maydell@linaro.org, laurent@vivier.eu, bharata@linux.vnet.ibm.com, andrew@andrewdutcher.com, qemu-devel@nongnu.org, Aurelien Jarno <aurelien@aurel32.net>


Richard Henderson <richard.henderson@linaro.org> writes:

> On 01/24/2018 05:13 AM, Alex Benn=C3=A9e wrote:
>> +/* Multiply A by 2 raised to the power N.  */
>> +static FloatParts scalbn_decomposed(FloatParts a, int n,
>> +                                          float_status *s)
>> +{
>> +    if (a.cls =3D=3D float_class_normal) {
>> +        a.exp +=3D n;
>> +    }
>> +    return a;
>> +}
>
> ...
>
>> -    if ( aExp =3D=3D 0x7FF ) {
>> -        if ( aSig ) {
>> -            return propagateFloat64NaN(a, a, status);
>
> This is where we used to raise inexact.
> In the new function we need to handle this as in round_to_int.

Why is the handling in round_canonical not good enough for this?

--
Alex Benn=C3=A9e