On 2019-11-11, at 09:08:39, Steve Smith wrote: > > I must agree that USING on numbers is a questionable feature; also operand > 1 doesn't have to be 0, anything up to 2gb should work. > What's "questionable"? Should the Assembler require a relocatable expression? Why?
An old (BitSavers) Assembler manual said the allowed range was (1-2**24,2**24-1). HLASM says, "non-negative". I don't believe either restriction was ever enforced. What does "negative" mean for a relocatable expression? Does it depdend on the address at which the CSECT/DSECT gets loaded? > ... My guess is somebody in 1964 thought it was a good idea. > Prior to the advent of immediate instructions there was no better alternative. -- gil
