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From: rhyde@dimaggio.ucr.edu (randy hyde)
Newsgroups: comp.sys.apple2
Subject: Re: ML subroutines (passing parameters in ML)
Message-ID: <13954@ucrmath.ucr.edu>
Date: 26 Apr 91 18:50:29 GMT
References: <3397@kluge.fiu.edu> <13845@ucrmath.ucr.edu> <112122@tut.cis.ohio-state.edu>
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Reply-To: rhyde@dimaggio.ucr.edu (randy hyde)
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>> Its quite simple (to access parameters on the stack) if you point the
   direct page at the stack...

True, it's easy, but you give up two important things about the direct page--
the ability to use it as a set of 256 scratch pad registers, and furthermore,
it's doubtful the dp would be page aligned costing you another cycle on each
dp memory access.

I've often wondered why compilers insist on using the dp as a frame pointer
rather than fixing dp (or pseudo-fixing it) and using register allocation
schemes like a RISC machine.  The resulting code would run quite a bit faster.