Message-ID: <5BF60CD649EDD411A04600B0D049F53A544468@hydmail02.hyd.wilco-int.com>
From: Prashant Ramachandra <rprash AT wilco-int DOT com>
To: "'djgpp AT delorie DOT com'" <djgpp AT delorie DOT com>
Subject: RE: Accessing registers from C
Date: Mon, 2 Jul 2001 09:47:09 +0530 
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Reply-To: djgpp AT delorie DOT com

On Monday, July 02, 2001 9:03 AM, Tom St Denis [SMTP:tomstdenis AT yahoo DOT com]
wrote:
| 
| > Everytime you use the variable "eax", you're actually accessing
| > or
| modifying
| > the eax register itself.
| 
| Perhaps, and by doing so you take away chances for GCC to optimize
| the code.

Yes, but it's useful in certain cases. I posted some code to check the CPU
type back in 1998. That's the simplest use I can think of. You might want to
see that. And the linux kernel uses lots of this, too. Do you think they
weren't concerned about optimizing ther kernel code?

| You might as well not write in C then.

You won't be using this in every function. So this doesn't justify anything.
--
Prashant TR <tr AT midpec DOT com>  Web: http://www.midpec.com/

"Those who do not understand Unix are condemned to reinvent it, poorly."
     -- Henry Spencer