Purpose and preservation of registers

[Triang3l]

Since we don't have a convention on register usage, how about making one, like for x86?

A convention on register naming would make writing libraries and creating calling conventions easier.

What do I propose:

• A - no proposal.
• B - base pointer - stores SP before allocating variables.
• C - counter - counter - used in loops.
• I and J - used for copying memory.
• X and Y - expression operands registers.
• Z - return value.

B is always pushed when calling a subroutine. Other registers (except for Z) are preserved if needed.

[Yamakaky]

I think we can use the A register for the return value

[Triang3l]

Why not Z? Z is the last Latin letter, symbolizes end of a function. A looks more general-purpose.

[hach-que]

There is already a register convention in the coding style guide line. I
don't see why we would need to be more strict in this area.

On Sunday, September 9, 2012, SiPlus notifications@github.com wrote:

Why not Z? Z is the last English letter, symbolizes end of a function.

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Regards, James Rhodes.
Redpoint Software

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