> > "... a good reason why small MVCs run slower than LG/STG pairs ... > > overhead at the beginning of an MVC ... check if the operands are on 'good' > > boundaries ... check for operand overlap ... length check ... [meanwhile] the > > LG/STG is far on its way. Anyone writing a length-1 MVC instead of an > > IC/STC would be laughed out of their code review. > > Rubbish. > KISS. > A move of length 1 is clear and unequivocal. > And it's only one line.
Nevertheless, IC/STC is what the newer mainframe compilers generate for a one-byte move. For the reasons given, it's less work for the system than an MVC.
