Re: [cc65] register usage when mixing assembler and C with cc65?

From: <>
Date: 2014-07-17 04:31:38
Am Donnerstag, 17. Juli 2014, 04:22:52 schrieben Sie:
> When I call external assembler functions from my C code, what are the rules
> for preserving the registers? I couldn't find it in the documentation.
> - does the C environment expect the assembler code to save the A/X/Y/flags
> register values?

no (this is not true for some runtime functions, but generally for user 
defined functions)

> Is there a difference between fastcall and normal defined functions with and
> without parameters?

no, you may generally clobber all


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Received on Thu Jul 17 04:35:40 2014

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