4–108 Alpha Architecture Handbook
Notes:
Except that it is likely in many implementations to be substantially faster, the instruction:
FCMOVxx Fa,Fb,Fc
is exactly equivalent to:
FByy Fa,label ! yy = NOT xx
CPYS Fb,Fb,Fc
label: ...
For example, a branchless sequence for:
F1=MAX(F1,F2)
is:
CMPxLT F1,F2,F3 ! F3=one if F1<F2; x=F/G/S/T
FCMOVNE F3,F2,F1 ! Move F2 to F1 if F1<F2