Re: Why ain't there no XILL?
Any standard logic text establishes that o AND, inclusive OR, and NOT are together universal, o NOR alone is universal, and o NAND alone is universal. Thus, in an obvious notation, XOR(a,b) =df (a | b) (¬(a b)) What is all the pother about? John Gilmore, Ashland, MA 01721 - USA -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Why ain't there no XILL?
I would assume the pother is because OIL and NIL are macros that provide or and and processing with serialization. Your notation fails to provide serialization. It should be relatively easy to create an XIL macro based on OIL or NIL however. === Wayne Driscoll OMEGAMON DB2 L3 Support/Development wdrisco(AT)us.ibm.com === From: John Gilmore jwgli...@gmail.com To: IBM-MAIN@listserv.ua.edu, Date: 08/02/2012 07:12 AM Subject:Re: [IBM-MAIN] Why ain't there no XILL? Sent by:IBM Mainframe Discussion List IBM-MAIN@listserv.ua.edu Any standard logic text establishes that o AND, inclusive OR, and NOT are together universal, o NOR alone is universal, and o NAND alone is universal. Thus, in an obvious notation, XOR(a,b) =df (a | b) (¬(a b)) What is all the pother about? John Gilmore, Ashland, MA 01721 - USA -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Why ain't there no XILL?
Serialization, performance, auxiliary storage and a related hardware realization: On Aug 2, 2012, at 07:46, Wayne Driscoll wrote: I would assume the pother is because OIL and NIL are macros that provide or and and processing with serialization. Your notation fails to provide serialization. It should be relatively easy to create an XIL macro based on OIL or NIL however. I was about to write that, then I RTFM. The P[ro]Ops describes NILL and OILL as quite different from NIL and OIL. A cursory reading does not show whether they are atomic for serialization in a MP environment. From: John Gilmore jwgli...@gmail.com Date: 08/02/2012 07:12 AM Any standard logic text establishes that o AND, inclusive OR, and NOT are together universal, o NOR alone is universal, and o NAND alone is universal. Thus, in an obvious notation, XOR(a,b) =df (a | b) (¬(a b)) What is all the pother about? That such a scheme requires auxiliary storage. That it is slower than a likely hardware implementation. That it may further require locking in a MP environment. Back in the Day of TTL SSI/MSI logic components, I looked at the spec sheets of two chips. The specs included low level circuit diagrams. One vendor called its component MSI and used roughly the formula you give. The other called its component SSI (fewer transistors) and accomplished the function by connecting a to the emitter of one transistor and b to its base, giving (a ¬b). b was connected to the emitter and a to the base of a second transistor, giving (b ¬a). The collectors were connected in parallel for (a ¬b) | (b ¬a), give or take a totem-pole output stage and a liberal seasoning with De Morgan's laws. A very clever and efficient disuse of what any standard logic text establishes. -- gil -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Why ain't there no XILL?
A weird way would be: _OR OPSYN OR OR OPSYN XR OIL ... OR OPSYN _OR This changes the OR instruction in the OIL macro into an XR instruction. Of course, this also ASSuMEs that OIL macro will never use more than one OR instruction. If you want, you can copy the OIL macro to your own MACLIB and change the name to XIL. Then physically change the OR instruction to XR in the new XIL macro. -- John McKown Systems Engineer IV IT Administrative Services Group HealthMarkets® 9151 Boulevard 26 . N. Richland Hills . TX 76010 (817) 255-3225 phone . john.mck...@healthmarkets.com . www.HealthMarkets.com Confidentiality Notice: This e-mail message may contain confidential or proprietary information. If you are not the intended recipient, please contact the sender by reply e-mail and destroy all copies of the original message. HealthMarkets® is the brand name for products underwritten and issued by the insurance subsidiaries of HealthMarkets, Inc. -The Chesapeake Life Insurance Company®, Mid-West National Life Insurance Company of TennesseeSM and The MEGA Life and Health Insurance Company.SM -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] On Behalf Of David Crayford Sent: Thursday, August 02, 2012 9:12 AM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Re: Why ain't there no XILL? On 2/08/2012 9:46 PM, Wayne Driscoll wrote: I would assume the pother is because OIL and NIL are macros that provide or and and processing with serialization. Your notation fails to provide serialization. It should be relatively easy to create an XIL macro based on OIL or NIL however. Please show us how to then! === Wayne Driscoll OMEGAMON DB2 L3 Support/Development wdrisco(AT)us.ibm.com === From: John Gilmore jwgli...@gmail.com To: IBM-MAIN@listserv.ua.edu, Date: 08/02/2012 07:12 AM Subject:Re: [IBM-MAIN] Why ain't there no XILL? Sent by:IBM Mainframe Discussion List IBM-MAIN@listserv.ua.edu Any standard logic text establishes that o AND, inclusive OR, and NOT are together universal, o NOR alone is universal, and o NAND alone is universal. Thus, in an obvious notation, XOR(a,b) =df (a | b) (¬(a b)) What is all the pother about? John Gilmore, Ashland, MA 01721 - USA -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Why ain't there no XILL?
David Crayford suggests that the pother to which I objected is perhaps: | Because it's not done in the hardware to make it self-documenting? which raises the question what he means by self-documenting. Machine instructions are not self-documenting. If z/Architecture instructions were self-documenting we should be able to dispense with the PrOp, which all of us in fact find indispensable. XOR is 'documented' by a simple four-row truth table, and anyone who cannot reproduce that truth table upon demand should not be a programmer. John Gilmore, Ashland, MA 01721 - USA -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Re: Why ain't there no XILL?
There are now XIHF and XILF to do an Xor of the high 32 bits or the low 32 bit (respectively) with an immediate fullword. Curiously, there are NIHF, NILF for fullword aNd Immediate fullword. But there are also NIHH, NIHL, NILH, NILL to do halfword and immediates to bits 0..15, 16..31, 32..47, and 48..63 of the specified 64-bit register. Likewise, replace the leading NI with OI for corresponding Or Immediate instructions. Why was Exclusive Or short changed to not have the halfword immediate variants? My guess is simply that IBM simply did not see any of their code which required this. The and and or instruction variants may have been implemented via multiple instructions in many places. I don't know. -- John McKown Systems Engineer IV IT Administrative Services Group HealthMarkets(r) 9151 Boulevard 26 * N. Richland Hills * TX 76010 (817) 255-3225 phone * john.mck...@healthmarkets.com * www.HealthMarkets.com Confidentiality Notice: This e-mail message may contain confidential or proprietary information. If you are not the intended recipient, please contact the sender by reply e-mail and destroy all copies of the original message. HealthMarkets(r) is the brand name for products underwritten and issued by the insurance subsidiaries of HealthMarkets, Inc. -The Chesapeake Life Insurance Company(r), Mid-West National Life Insurance Company of TennesseeSM and The MEGA Life and Health Insurance Company.SM -Original Message- From: IBM Mainframe Discussion List [mailto:IBM-MAIN@LISTSERV.UA.EDU] On Behalf Of Shmuel Metz (Seymour J.) Sent: Thursday, August 02, 2012 11:16 AM To: IBM-MAIN@LISTSERV.UA.EDU Subject: Re: Why ain't there no XILL? In 50195a2f.3030...@dignus.com, on 08/01/2012 at 12:32 PM, Thomas David Rivers riv...@dignus.com said: Maybe they were running out of acreage? But XOR is very doable with a few NOTs, ANDs and ORs... Aren't OIL and NIL MVS macros rather than z instructions? The exclusive or instructions have been present since the dawn of Time, so why not write your own XIL macro if you need it? There's no need to do X with multiple instructions. -- Shmuel (Seymour J.) Metz, SysProg and JOAT Atid/2http://patriot.net/~shmuel We don't care. We don't have to care, we're Congress. (S877: The Shut up and Eat Your spam act of 2003) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to lists...@listserv.ua.edu with the message: INFO IBM-MAIN
Why ain't there no XILL?
NILL? check. OILL? check. XILL? not present -- Binyamin Dissen bdis...@dissensoftware.com 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 lists...@listserv.ua.edu with the message: INFO IBM-MAIN
