Subject: Re: bcopy, bzero, copypage, and zeropage
To: Jason Thorpe <>
From: Chris G Demetriou <>
List: tech-kern
Date: 12/14/1996 13:31:33
> This eliminates unnecessary code size and overhead from indirect
> function calls in the critical path.

Oh, and while i'm at it:

One some architectures, there's really no overhead difference between
a 'direct' and 'indirect' function call.  There's always cpu-cycle
overhead for comparisons and branches, not to mention the additional
memory load that they can cause (test

Code size is a good argument for single-function implementations, but
i'm not completely convinced that even on the m68k that the "indirect
function call" one is, for "generic" implementations.  (See my
previous message for a good way to remove all potential overhead for
"specific" implementations.)

On some architectures, all you're left with is code size.  While
that's a good argument, well, welcome to the wonderful world of
space-time tradeoffs.  8-)