Forgot to mention... use of 8 byte immediate values implies support for them at 
the EQU level as well... 

CTLBNAME   EQU   C'CTLBNAME'  (which is currently limited to just 4 bytes) 

One of the few types of instructions which kind of supports an 8 byte immediate 
value are the compare logical immediates, but only if you're okay with the high 
order 32bits of the immediate value being zero.    

FWIW, I dislike use of lower case for instruction mnemonics and operands, but 
have grown to appreciate LC for struc labels and comments. 

Mike 

-----Original Message-----
From: IBM Mainframe Assembler List [mailto:[email protected]] On 
Behalf Of Mike Hochee
Sent: Saturday, October 24, 2020 5:55 PM
To: [email protected]
Subject: Re: Reversed string macro

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You can also do it with two MVHHI instructions. (which I tend favor!)

Your question also seems to highlight the need for a store immediate that 
supports a 4 byte immediate value, if for no other reason than to complement 
the load logical immediate instructions.

I know the sky is not the limit here, but I could definitely find uses for 8 
byte immediate values as well.

Mike
-----Original Message-----
From: IBM Mainframe Assembler List [mailto:[email protected]] On 
Behalf Of Charles Mills
Sent: Saturday, October 24, 2020 5:24 PM
To: [email protected]
Subject: Re: Reversed string macro

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Why not? What's wrong with MVI/MVC for 3?

Given that it would involve no storage references beyond the target and 
i-cache, I wonder if the fastest way to set four bytes, without the string 
appearing in storage, might not be four sequential MVI's.

Charles


-----Original Message-----
From: IBM Mainframe Assembler List [mailto:[email protected]]
On Behalf Of Tony Thigpen
Sent: Saturday, October 24, 2020 2:07 PM
To: [email protected]
Subject: Re: Reversed string macro

I kinda like the concept, but a lot of literals we use are just 4 characters, 
so it does not scale down easily.

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