On Wed, 30 May 2007 11:45:10 -0700 Edward Jaffe <[EMAIL PROTECTED]> wrote:
:>Binyamin Dissen wrote: :>> Why would an AMODE change require a pipline flush? It doesn't branch anywhere. :>> The current pipline should be valid. :>I simply indicated that, in *my* experience, address mode switching is :>fairly expensive and suggested one possible cause. (FWIW, I've found :>similar "slowness" occurs for other PSW-change instructions as well :>e.g., changing the PSW key or translation mode.) A key change caused a slowdown? Interesting. I have lots of code where it switches to key0 for a few instructions. I was reading the POPs regarding machine checks, and it did indicate that the PSW is built of a few separately maintained pieces (with a separate validity bit for each section). :>Rather than argue about it, I suggest you run your own benchmarks. Not arguing - just trying to understand why. -- Binyamin Dissen <[EMAIL PROTECTED]> http://www.dissensoftware.com Director, Dissen Software, Bar & Grill - Israel Should you use the mailblocks package and expect a response from me, you should preauthorize the dissensoftware.com domain. I very rarely bother responding to challenge/response systems, especially those from irresponsible companies. ---------------------------------------------------------------------- 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
