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Re: Fix ctan, ctanh of subnormals in round-upwards mode (bug 14328)


On 07/09/2012 09:35 AM, Joseph S. Myers wrote:
> On Mon, 9 Jul 2012, Adhemerval Zanella wrote:
>
>> On 07/08/2012 05:17 PM, Joseph S. Myers wrote:
>>
>>> Actually I noted that sqrt (epsilon) is really what's relevant here (just 
>>> not convenient to write generically), so you might as well use DBL_EPSILON 
>>> or 0xp1-53L or similar.
>>>
>>> I'd say such constants are better written as hex floats, 0x1p-106L in this 
>>> case (any floating-point constant where you intend an exact bit pattern 
>>> for a particular floating-point format is better written as a hex float 
>>> unless there is a short exact decimal expansion for it).
>>>
>> Thanks for the review, I'll rewrite the epsilon constant as hexa format, 
>> but I think it is best to keep the ldbl-128ibm implementation close to 
>> the one you already committed, instead of fix the spurious overflow 
>> using another logic. Don't you think?
> Yes, keeping the implementations similar makes sense in the absence of any 
> attempt to do something special for the discontiguous mantissas of 
> ldbl-128ibm.
>
So I believe the patch is ok, right?


-- 
Adhemerval Zanella Netto
  Software Engineer
  Linux Technology Center Brazil
  Toolchain / GLIBC on Power Architecture
  azanella@linux.vnet.ibm.com / azanella@br.ibm.com
  +55 61 8642-9890


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