vrsub.vi, used as negation


CDS <cohen.steed@...>
 

Is the point of vrsub.vi to provide negation? From a compiler/user perspective, completing the vsub pattern with vsub.vi (even as a virtual instruction) may be a usability enhancement to consider.

 


Andrew Waterman
 

Would be mostly redundant with vadd.vi, since the immediate operand is signed. (Same reason the scalar ISA doesn’t provide a subi instruction.)

On Fri, Aug 7, 2020 at 8:52 AM CDS <cohen.steed@...> wrote:

Is the point of vrsub.vi to provide negation? From a compiler/user perspective, completing the vsub pattern with vsub.vi (even as a virtual instruction) may be a usability enhancement to consider.