Didn't think of that, but you are probably right - pipeline stalls are quite expensive and tough to benchmark.
Peter -----Original Message----- From: IBM Mainframe Assembler List [mailto:ASSEMBLER-LIST@LISTSERV.UGA.EDU] On Behalf Of Paul Gilmartin Sent: Saturday, June 16, 2018 9:41 PM To: ASSEMBLER-LIST@LISTSERV.UGA.EDU Subject: Re: Count Words? EXTERNAL EMAIL On 2018-06-16, at 18:53:32, Farley, Peter x23353 wrote: > > The PoP says for the Vector String instructions that "For all instructions > that optionally set the condition code, performance may be degraded if the > condition code is set." > I suspect it's not that the Vector String instruction itself performs poorly, but that a pipeline which depends on a pending condition code may be stalled. Tough to benchmark. Now, if the hardware keeps (multiple) speculative condition codes ... -- This message and any attachments are intended only for the use of the addressee and may contain information that is privileged and confidential. If the reader of the message is not the intended recipient or an authorized representative of the intended recipient, you are hereby notified that any dissemination of this communication is strictly prohibited. If you have received this communication in error, please notify us immediately by e-mail and delete the message and any attachments from your system.
