List of PSP CPU definitions

[m0skit0]

I suggest you rename the thread to Allegrex or PSP. Those instructions are not MIPS standard.

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[Zecoxao]

Thanks for the help Nymphaea, and no I'm not too lazy to do it by myself, let's just say that I had some "issues" in Networks class about that "lazyness" subject while I wrote that post
m0skit0, I've redefined the topic's name, thanks for mentioning that out, AFAIC, there was no difference between saying MIPS and saying Allegrex.

PS: You're right Nymphaea, I got this from a book of MIPS 1000-4000 processors (It's called MIPS Programmers HandBook), but my idea was that the instructions where exactly the same. Guess I was wrong . Also, I've never used BBCode, hence that mess

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[m0skit0]

m0skit0, I've redefined the topic's name, thanks for mentioning that out, AFAIC, there was no difference between saying MIPS and saying Allegrex.

Allegrex has new instructions not defined on the MIPS standard, such as LA, quoted by Nymphaea. Never seen this one personally though, as well as a lot of other instruction she put. Can you please reference these instructions somewhere, Nymphaea? Thanks. Also Allegrex has no TLB (or it's disabled by hardware), which I think is a standard on MIPS architectures.

I would also suggest you put a more "noobish" name, if I may say, like PSP's CPU or something like that

[Nymphaea]

You did what I told you not to do, and erased the stuff I left out, blaaah XD pretty sure there is an edit history here, might be able to get the few other things back.

LA is a pseudo-instruction, it's actually 2 instructions, LUI followed by ORI, so basically how you would load an address normally, just a single line in your source file

I guess I'll try filling this out more, the Allegrex-unique functions are still missing(like "HI" and "LO", I believe are instructions) and maybe make those function definitions a bit more descriptive. It would be nice if double spoilers were possible to make that clean, but oh well.

[Zecoxao]

You did what I told you not to do, and erased the stuff I left out, blaaah XD pretty sure there is an edit history here, might be able to get the few other things back.

Read first the OP xD. It's safely stored on Notepad in my laptop . Don't worry, the rest will be put there

PS: If you want the OP, send me a PM.

Edit: Never mind the PS, i put the OP in a big spoiler at the bottom of the other one

[m0skit0]

I would suggest not to use pseudo-instructions, they can be quite mis-leading, specially if you're writing assembly code for exploits (shellcodes or eggs). The resulting code is not what you wrote originally, since those instructions will be expanded. Also you would learn better MIPS if you don't use pseudo-instructions IMHO.

Anyways, keep it up!

[Zecoxao]

I would suggest not to use pseudo-instructions

If only i knew what was that (it looks to me an instruction that is actually a set of two instructions )
edit: I still have some problems understanding what i should remove and what i shouldn't. If you're not too busy, could you make me a list of what should I take away?

[m0skit0]

Pseudo-instruction is an instruction that actually translates into various other instructions when assembling. That is, that instruction doesn't exist for the processor.

[Zecoxao]

I removed blt, bgt, ble, blt, bge, li, move that, according to wikipedia, are pseudoinstructions. Know anymore that I can delete?

[m0skit0]

At least 50% of what Nymphaea posted are pseudo-instructions, but you can't be sure when talking about Allegrex since there's no official documentation.

Also I must say that some pseudo-instructions are actually aliases for other instructions, that is, it's the same instruction with just another name (which are the ones you removed, actually).