I am clearing the area to X'00' so the usual suspects (SR, XR, SLR, LHI) each do it in one instruction.
Charles -----Original Message----- From: IBM Mainframe Assembler List [mailto:[email protected]] On Behalf Of Steve Smith Sent: Thursday, August 17, 2017 12:04 PM To: [email protected] Subject: Re: Source address significance for clearing MVCL HLASM doesn't do "obviously I meant" (aka DWIM). The source address register is ignored, doesn't have to be cleared, and will not be changed, when the source length is 0. btw, the cool modern way to set that with one instruction is LLILH Rx,x'4000' (e.g.). Fair warning, this clears the high-word, if that matters to your program or environment.
