I think the author is confused.
I think the author is confused. Protecting a code segment to be 'read only' does not change a machine from "Von Neumann" to "Modified Harvard" architecture. That distinction is reserved for computers that separate the 'store' (aka volatile memory) into two disjoint regions. And pure Harvard architecture machines (like the early PIC series from Microchip) suffer from an in ability to vary the partition between data and code, which is the real problem[1]. Now there is a pretty sound reason for making your code segment read only, and the author touches on it, which is that if you are running third party code, because it limits the attack surface for security exploits somewhat. But then he goes off the rails with this claim, "What really struck me was that there was no flexibility here; no way to for a program to make changes to itself or build new subprograms, even if Microsoft approved it." The next topic on the required reading list should be "Turing complete" :-) It is entirely possible to write a piece of code which is both a core interpreter, and the byte codes on which that interpreter is operating. And including in the byte codes a means to read, modify, and re-execute any previous byte codes. The sum of actions of course will be constrained by what can be expressed in a byte code but given that, you are free to do what ever you want. And of course any interpreter which was interspersing its data and executable byte codes in the same chunk of memory, well that would be a Von Neumann architecture :-) [1] Harvard machines ultimately fell out of favor because you could end up with left over code store and not enough data store for an application.
Posted by ChuckMcM on Jun 10, 2015, 8:26 PM
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I mean that's the problem though.
I've always believed the opposite: get conditionals deep in your code so that the higher level control flow is regular.
The biggest problem with AI isn't being able to do things.
I am a 3D printing maker type nerd (I make my own tools for other creative tasks, rather than as their own outcomes) and I saw an incredi...
Of course not, those are clearly scams.
Claude makes more detailed plans that seem better if you just skim them, but when analyzed, has a lot of errors, usually.
Effectively everyone is building the same tools with zero quantitative benchmarks or evidence behind the why / ideas … this entire s...
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I think the author is confused.
I think the author is confused. Protecting a code segment to be 'read only' does not change a machine from "Von Neumann" to "Modified Harvard" architecture. That distinction is reserved for computers that separate the 'store' (aka volatile memory) into two disjoint regions. And pure Harvard architecture machines (like the early PIC series from Microchip) suffer from an in ability to vary the partition between data and code, which is the real problem[1]. Now there is a pretty sound reason for making your code segment read only, and the author touches on it, which is that if you are running third party code, because it limits the attack surface for security exploits somewhat. But then he goes off the rails with this claim, "What really struck me was that there was no flexibility here; no way to for a program to make changes to itself or build new subprograms, even if Microsoft approved it." The next topic on the required reading list should be "Turing complete" :-) It is entirely possible to write a piece of code which is both a core interpreter, and the byte codes on which that interpreter is operating. And including in the byte codes a means to read, modify, and re-execute any previous byte codes. The sum of actions of course will be constrained by what can be expressed in a byte code but given that, you are free to do what ever you want. And of course any interpreter which was interspersing its data and executable byte codes in the same chunk of memory, well that would be a Von Neumann architecture :-) [1] Harvard machines ultimately fell out of favor because you could end up with left over code store and not enough data store for an application.
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