[LLVMdev] [PATCH][RFC]: Add fmin/fmax intrinsics

[Owen Anderson]

On Sep 17, 2014, at 2:44 PM, Matt Arsenault <arsenm2 at gmail.com> wrote:

> 
> On Sep 15, 2014, at 4:17 PM, Owen Anderson <resistor at mac.com> wrote:
> 
>> I’d be fine with that proposal.  I could even be convinced if we wanted to add a pair of NaN-propagating intrinsics as well, for targets and languages that want those semantics, even if I disagree with them.  I do think that, if we are using the minnum/maxnum names, we should explicitly note that they are equivalent to C’s fmin/fmax, but not std::min/std::max or Java(script)’s min/max.
>> 
>> —Owen
>> 
>> 
>>> On Sep 15, 2014, at 12:26 PM, Dan Gohman <dan433584 at gmail.com> wrote:
>>> 
>>> Given IEEE-754's sway, and its saying what it does on this point, but given also the popularity of NaN-propagating min and max, how about a compromise? We add intrinsics following the IEEE-754 semantics, but we also follow IEEE-754 (and ARMv8) in renaming them to minnum and maxnum, to clarify which interpretation these intrinsics are using.
>> 
>> 
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> 
> I can rename these, but the convention followed by all the other LLVM intrinsics follow the C library names

minnum and maxnum matches their names in the IEEE 754 standard.  It diverges LLVM’s convention, but the names are not without precedent.

—Owen