Out of curiosity, were you compiling with the OPT compiler option? If not, does changing to that generate the same instructions?
"Farley, Peter x23353" <[email protected]> wrote in message news:<053f2631ec9c584883847c8b4970a22804998...@josqems1.jsq.bsg.ad.adp.com>. .. > I am in the midst of a CPU optimization exercise for a COBOL program and > ran across the following code sequence generated by the compiler: > > MVI 254(3),X'40' > MVC 255(119,3),254(3) > > This code is generated in response to a simple COBOL "MOVE SPACES TO > variable" instruction, where the variable is 120 bytes long. > > Did I or did I not see some discussion here or perhaps in a SHARE > presentation that on a z10 machine overlapping/destructive moves wreck > the pipeline and take *much* longer to execute as a result? Or am I > imagining that? > > The reason I ask is that Strobe highlights this place in the code as a > high-usage point, and I am struggling to understand why. > > TIA for any info you can provide. > > Peter > ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
