PowerPC For Dummies: A simplified guide to understanding the PowerPC Instruction Set

[JimmyKazakhstan]

Thanks! Although I have a few counter questions.


1. 
So this part is actually correct?

Code:

With Update = An address will be placed into a register after execution of an instruction.

Algebric = The user specified value in an instruction will be treated as a 32 bit value.

Indexed = Calculates an address after execution of an instruction

I sent the page to one of the people who helped with the guide (and is familiar with PowerPC) to get his input, but he never responded when I sent him these, what I wrote for those are mostly assumptions, are those the actual definitions?

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2. 

Code:

An Fyi. Li is a simplified mnemonic for addi

i.e. li r1, 1 = addi r1, r0, 1 #Broadway treats r0 as literal 0 when it's used as a source register in this instruction

Do you know what specific instructions treat r0 like this? I want to label them for the guide. 
(I know in the sentence below you say that there are too many to list, but what are the main ones?)

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3. 

Code:

In the Broadway manual i see nothing about bun, bnu, bdznt, bdnzf, and bdz branches. Are these present in other PPC chips? An fyi, the disassembler used in Dolphin is a generic PPC disassembler, so it will show instructions that simply don't exist in Broadway. Maybe these are simplified mnemonics not referenced in the manual?

Not a question. But look at page 523 - 526 of this pdf. There are many, many, many, many.... many.... many... branch instructions types........

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4. 

Code:

example:
r3 = 0x80000000; VALUE = 0x1500
stwu r0, 0x1500 (r3)
Before instruction was executed; r3 was 0x80000000
After instruction has executed; r3 is now 0x80001500

In this context, what is r0 for? I've never really fully understood the "update" instruction types.

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5.

Code:

Your definition for NOT is incorrect. NOT is not the negative of a value. Its a simplified mnemonic for NOR'ing a register with itself

Hmm, well the person I've been showing the page to told me it made values negative. But what exactly does it mean to "NOR" a value? I only know of the term of it.

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6.

Code:

Regarding your quick description of an fpr, you should add in a note that the floating value is in its 64-bit form

I was going to put something like this, but on the psq description page on the smash forum I linked in another forum category here, it mentions that dolphin has a weird issue where it will display the same value twice in the fpr display in debug mode, even if it's not a double, something like that. It confused me, which means it most likely will confuse everyone else.

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7.

Code:

Bit is not a single digit within a word (its not half of a byte).

What would be a better term I could put for what I labeled as a "bit" on the site?

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Last Question

8. 

On the Operation Instructions Section of the site
What I put for AND and OR is actually correct? I just want to be sure, the person I've been showing the site too didn't respond about it yet.