Sorry, I was a little cryptic. The compare and swap is generally on your lockword and you should be incrementing that for each iteration. This is not an easy to understand instruction. I mean what normal instruction needs over 13 pages to explain it? I do a function code 0 to get the lock count, then gather all my before values, calculate my after values and then do the real PLO. If something else has updated the structures between the first and second PLO instructions, you go back and start over.
Chris Blaicher Technical Architect Software Development Syncsort Incorporated 50 Tice Boulevard, Woodcliff Lake, NJ 07677 P: 201-930-8234 | M: 512-627-3803 E: [email protected] -----Original Message----- From: IBM Mainframe Discussion List [mailto:[email protected]] On Behalf Of Donald Likens Sent: Monday, April 27, 2015 1:06 PM To: [email protected] Subject: PLO Function Codes 16-19 What am I missing? Isn't PLO Function Codes 16-19 (Compare and Swap and Double Store) updating three locations? Direct out of the "Principle of Operations": The first-operand comparison value is compared to the second operand. When the first-operand comparison value is equal to the second operand, the first-operand replacement value is stored at the second-operand location, the third operand is stored at the fourth-operand location, the fifth operand is stored at the sixth-operand location, and condition code 0 is set. I see three stores in the above text. I've been using this successfully for a while updating two different locations, but now I want to update three and do not see a need to "Compare and Swap and Triple Store". ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN ________________________________ ATTENTION: ----- The information contained in this message (including any files transmitted with this message) may contain proprietary, trade secret or other confidential and/or legally privileged information. Any pricing information contained in this message or in any files transmitted with this message is always confidential and cannot be shared with any third parties without prior written approval from Syncsort. This message is intended to be read only by the individual or entity to whom it is addressed or by their designee. If the reader of this message is not the intended recipient, you are on notice that any use, disclosure, copying or distribution of this message, in any form, is strictly prohibited. If you have received this message in error, please immediately notify the sender and/or Syncsort and destroy all copies of this message in your possession, custody or control. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO IBM-MAIN
