qemu-arm
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Qemu-arm] [Qemu-devel] [PATCH 1/2] softfloat: Enable run-time-confi


From: Leon Alrae
Subject: Re: [Qemu-arm] [Qemu-devel] [PATCH 1/2] softfloat: Enable run-time-configurable meaning of signaling NaN bit
Date: Mon, 4 Apr 2016 17:10:24 +0100
User-agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0

On 03/04/16 15:25, Aleksandar Markovic wrote:
> It just seems to me that, in similar case, 16-bit default NaN value should be 
> 0x7E00. This value is needed for MSA operations. ("MIPS Architecture for 
> Programmers Volume IV-j: The MIPS32® SIMD Architecture Module", Revision 
> 1.12, (february 3, 2016), page 52, table 3.7 "Default NaN Encodings")
> 
> I plan to include all three corrections in the next version of this patch 
> set. Please, let me know if you think that I should not.

Great, thanks.

Also, the pickNaNMulAdd() for MIPS requires updating to match "3.5.3 NaN
Propagation" from the same MSA doc:
"When two or three operands are NaN, the payload of the resulting NaN is
identical to the payload of one of the input NaNs selected from left to
right as described by the instruction format".
This indicates the "c, a, b" order instead of "a, b, c" which is
currently implemented.

Regards,
Leon




reply via email to

[Prev in Thread] Current Thread [Next in Thread]