Re: [PATCH] Remove alpha specific fmax, fmin to fix sNaN handling [BZ #20947]

[Adhemerval Zanella <adhemerval dot zanella at linaro dot org>]

On 03/01/2018 16:23, Joseph Myers wrote:
> On Wed, 3 Jan 2018, Adhemerval Zanella wrote:
> 
>> Although the manual I am using (Alpha Architecture Handbook version 3),
>> notes that CVTfi OUTPUT Exceptions (B.3 Mapping to IEEE Standard)
>> should not generate Inexact, the manual of the chip I am testing it
>> (Alpha 21264 [1]) states at A.8 IEEE Floating-Point Conformance that
>> CVTfi and CVTif OUTPUT does generate inexact exception for inexact
>> result.  I think easier solution is just use generic implementation
>> for alpha.
> 
> Sure.  Presumably this applies to all of ceil, floor and trunc.  And a GCC 
> bug should be filed for inlining those functions on alpha in the default 
> -ffp-int-builtin-inexact case which allows the exception to be raised.
> 

Indeed trunc is also affected, although because addt/suc and subt/suc,
which for 21264 raises inexact for inexact result.  I will track trunc
in another bugzilla and open a gcc one as well.