This currently is. Possibly an MF=L in the static area.
MF=L in the DSECT Copy static to DSECT and use MF=E Or am I missing something obvious? On Tue, 27 Aug 2024 17:37:58 +0200 Bernd Oppolzer <[email protected]> wrote: :>Some topic drift: :> :>for one of my customers, I had to change some very old ASSEMBLER :>programs (1980 era) because of :>serious SIIS issues ... programs modifying static areas near the :>instruction stream, thereby invalidating :>cache lines and leading to performance issues. :> :>One of the problem areas were IBM macros such as TIME DEC (IIRC), which :>modify their inline parameter list. :>The examples can be found on the web, I think. Other areas are inhouse :>macros, which had the same or :>similar issues. :> :>There is a IMO clever idea at this customer's site: :> :>if a global macro symbol &GBREN is set, all macros put their temporary :>storage in a certain DSECT :>which is then allocated/getmained at program startup (together with the :>save area) and freed at the end. :>The base register is 13 ... which is needed anyway to address the save :>area. :> :>This way, the SIIS problems disappear at the same time, because the :>target addresses of the store :>and move instructions of the macros now are far away from the :>instruction stream. :> :>I fixed most of the SIIS problems of my customer by "cheating" and :>telling the programs that they were :>RENT (by setting &GBREN), when in fact they were not. And then I :>supplied a static area instead of the :>dynamic area (which is used with true RENT) and addressed this area :>using "dependent USING". :> :>My question now: :> :>what do you think of the idea asking IBM to provide a similar technique :>(an optional parameter, :>like MF=L and MF=E, which is present on almost all macros) on their :>macros, so that the :>definition of the work areas can be put in another (separate) DSECT ? :>This would IMO make :>the creation of RENT programs which include IBM macros so much easier :>... and help us :>solve some SIIS problems. :> :>Kind regards :> :>Bernd :> :> :> :>Am 27.08.2024 um 15:10 schrieb Peter Relson: :>> ... :>> :>> Will the macros ever be "changed" from using "LA" or "LAE" to some long-displacement form unconditionally? Surely "no". That's the same 6-byte vs 4-byte consideration. :>> Conditionally? Maybe. But only if a formal request is submitted. And it's more likely to happen for those macros that are tool-generated (as many of the macros created since the mid 80's are). :>> :>> ... :> :>---------------------------------------------------------------------- :>For IBM-MAIN subscribe / signoff / archive access instructions, :>send email to [email protected] with the message: INFO IBM-MAIN -- Binyamin Dissen <[email protected]> http://www.dissensoftware.com Director, Dissen Software, Bar & Grill - Israel ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
