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From: markw@gvlf1-c.gvl.unisys.com (Mark H. Weber)
Newsgroups: comp.sys.m68k
Subject: Re: Code too Big to ROM - where do we optimize
Message-ID: <590@gvlv2.GVL.Unisys.COM>
Date: 26 Mar 90 15:08:46 GMT
References: <5873@tekig5.PEN.TEK.COM>
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Organization: Unisys Defense Systems, Great Valley Labs, Paoli, Pa
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In article <5873@tekig5.PEN.TEK.COM> barbaras@tekig5.PEN.TEK.COM (Barbara Ann Siefken) writes:
>Our code is too big to ROM.  Are there some assembly language
>statements or processes that are known to take less space if
>done another way?  Is that simplifying the question too much.
>
One area to check would be the usage of macros vs. subroutines. A macro is
expanded in place each time it is used, so there may be many copies of
the same code being generated. A subroutine may be substituted for the
macro so that only one copy of the code is generated. Unfortunately there
is slightly more overhead in a subroutine call (pushing/popping things
from the stack). Generally, macros are used to optimize for high speed,
and subroutines are used to optimize for small code size. Hope this helps!

Mark

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  Mark H. Weber                   | Internet: markw@GVL.Unisys.COM  
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