>STCK does not show such a restriction. It used to. Those of us with long-ago-enough knowledge remember that well.
Regardless, if there is a chance of an operand crossing a cache-line boundary, it might be in your best (performance, not functional) interest to make sure that it doesn't (if you have such control). The easiest way of doing that for an 8-byte operand is usually to make it doubleword-aligned. This applies not just to STCK/STCKF. Some operands, such as those for CDS and CSG must be doubleword-aligned. Some operands must be quadword-aligned (e.g., CDSG, LPQ). For those if the operand is below 2G, you might need to avoid the default behavior of GETMAIN and STORAGE OBTAIN which is to obtain storage on a doubleword boundary (such as by using the STARTBDY keyword). Peter Relson z/OS Core Technology Design ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
