I like your response. Its near impossible to understand the IBM structured macros, but the Mainstar and TMON VTAM versions were quite understandable, at least to me.
At ASG TIMS used the IBM versions, as did the manager of TMVT, but Parker, walker carter et. al. hate them. -----Original Message----- From: IBM Mainframe Assembler List [mailto:[email protected]] On Behalf Of DASDBILL2 Sent: Wednesday, December 04, 2013 2:16 PM To: [email protected] Subject: Re: Base-less programming If everything else were equal (which it probably isn't), code like that sounds like a good reason to use structured Assembler macros. Bill Fairchild Franklin, TN ----- Original Message ----- From: "Tony Thigpen" <[email protected]> To: [email protected] Sent: Wednesday, December 4, 2013 2:16:41 PM Subject: Re: Base-less programming I try to balance the use of B *+2+4 style branches against the cluttering up by using a bunch of labels. It's never for more than 2 instructions. Nothing worse than looking at long series of tests followed by bit setting instructions where every other instruction has a label. Tony Thigpen -----Original Message ----- From: Chris Craddock Sent: 12/04/2013 02:58 PM >> Date: Wed, 4 Dec 2013 13:37:31 -0600 >> From: [email protected] >> Subject: Re: Base-less programming >> To: [email protected] >> > <snip>> > >>> Am I reading the book right? >>> >> >> No. Although the assembled instructions have the displacement in half >> words, your source code should still use the original "offset". HLASM >> itself will halve the value. And it will complain bitterly if the >> offset is not even. So you just replace the B??? with J??? and leave >> the operand itself alone. > > Well.. yes, but being pedantic; how about just using a label?!? I cringe > whenever I see carefully crafted branch statements with instruction lengths. > That's trivially broken by any down-stream change, whereas a label as a jump > or branch target will never be wrong - no matter how much the code changes in > between. Make your own and the next poor fool's job easier. > Just saying.... > CC >
