> -----Original Message----- > From: IBM Mainframe Discussion List > [mailto:[EMAIL PROTECTED] On Behalf Of Edward Jaffe > Sent: Wednesday, May 30, 2007 11:45 AM > To: [email protected] > Subject: Re: Is there a cost in switching AMODEs? > > > Binyamin Dissen wrote: > > Is there much of a cost to switching amodes? > > > > Is it worth writing code to be able to run completely in 64 > bit mode (and > > maintain the top half of the registers) or is it fine to > switch in and out > > when referencing storage above the bar? > > > > POPs does not indicate anything. > > > > In my experience, excessive switching of addressing mode is quite > expensive. I suspect it's because the entire pipeline must be flushed. > > -- > Edward E Jaffe
So, I would gather that your recommendation, in general, would be to stay in AMODE 64 whenever possible (assuming AMODE 64 is needed at all), changing AMODEs only when necessary to invoke a service or program which is AMODE 64 intolerant? If using UNIX services, then I guess it would be better to use the AMODE 64 version of the service instead of the AMODE 31 version, again assuming that AMODE 64 is needed in other parts of your program. -- John McKown Senior Systems Programmer HealthMarkets Keeping the Promise of Affordable Coverage Administrative Services Group Information Technology The information contained in this e-mail message may be privileged and/or confidential. It is for intended addressee(s) only. If you are not the intended recipient, you are hereby notified that any disclosure, reproduction, distribution or other use of this communication is strictly prohibited and could, in certain circumstances, be a criminal offense. If you have received this e-mail in error, please notify the sender by reply and delete this message without copying or disclosing it. ---------------------------------------------------------------------- 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
