From: Bill Frantz <frantz@netcom.com>
Date: Thu, 19 Dec 1996 21:48:36 -0800 (PST)
To: cypherpunks@toad.com
Subject: Re: Code+Data separation
In-Reply-To: <v02140b01aedf4fba9ec3@[192.0.2.1]>
Message-ID: <v03007804aedfd804957e@[204.31.236.106]>
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At 12:08 PM -0800 12/19/96, Peter Hendrickson wrote:
>Are there any modern processors which keep the code and data separated?

Many modern processors keep separate L1 caches for code and data.  Sparc
architecture requires a special instruction to say, "I have just used data
operations to change this part of the program."  I assume that program
fetchers and linkers must use this instruction.

Keeping separate main memory makes program loading and in-memory dynamic
linking hard.  The linker's data is the processor's program.


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