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Re: [f-cpu] Re: Floating-Point?



On Thu, 16 Aug 2001, Michael Riepe wrote:

> On Wed, Aug 15, 2001 at 11:15:33PM -0600, Ben Franchuk wrote:
> [...]
> > Ok what about instruction decoding of the opcode in a configuration
> > register with each setup modifying the fields used?
> > version 1 - endian bit active high
> > version 2 - endian bit active low
> > ( Special register xor endian flag ).
> 
> No, no, three times NO!
> 
> Can you imagine what happens when a piece of code runs with the wrong
> configuration settings?  *kaboom* FUBAR.
> 
> Don't you remember the `D' flag in Intel's x86?
> 
> Let's not duplicate this insanity.  A configuration register should
> NEVER affect the semantics of a program.  The configurable translation
> (size bits -> register size) is already too much, from a programmer's
> point of view.

I agree to your opinion! Basically, if one uses a toggle
type register it is always hard to detect the current
setting, i.e. this requires extra code... and thus slows
down the program -> a penalty you don't want at all.

JG

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