I noticed the new COBOL compiler was generating:

MVHHI target,0
MVHHI target+2,48000

instead of:

MVC target,=F'48000'

and I thought I'd look into using 2 MVHHI's instead of a MVC with a literal 
even when the top half of the value is non-zero.  The assembler happily accepts:

MVHHI target+2,C'abcd'

truncating the leading 'ab', but I gave up since I could not determine how to 
consistently obtain the top half of the value when it is a general (resolvable 
at assembly) expression, except by doing:

MVHHI target,0
ORG   *-2
DC    A(expression)
ORG   *-2
MVHHI target+2,expression

HLASM need logical shift operations to avoid requiring ORG/DC/ORG in the 
generate code.

Robert Ngan

-----Original Message-----
From: IBM Mainframe Assembler List [mailto:[email protected]] On 
Behalf Of Paul Gilmartin
Sent: Wednesday, March 01, 2017 11:54
To: [email protected]
Subject: Re: HLASM anomaly

On 2017-03-01, at 10:00, Charles Mills wrote:

> For sure! It's not a problem I lose sleep over -- perhaps because my
> primary language is now C++, no longer assembler.
>
> I don't recall ever thinking about the issue until it came up on this list.
>
> I'm a "design elegance" guy. It would please me if there were a single
> expression processor such that the syntax of immediate operands and of
> DC's of the same length were the same.
>
What lengths do you want?  There are:
         DC    AL1(expression)  1 byte;  unsigned
         DC    Y(expression)    2 bytes; signed
         DC    A(expression)    4 bytes; signed

Does HLASM issue any operand range warnings for any of LLI[HL][FHL]?
Is this implied by the PoOps "The condition code is unchanged."  Or, does HLASM 
simply ignore bits 0-15 of the immediate operand expression?
Is this documented?

-- gil

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