[fpc-devel] Re: On a port of Free Pascal to the IBM 370

[Mark Morgan Lloyd]

waldo kitty wrote:

>>  > No, I know exactly what I mean. Label and section names are under the
>>  > same rules in an assembler program on the 370, and a CSECT in 370
>>  > Assembly language
>>
>> I suspect that this will depend on the target operating system, so the 
>> Linux ABI
>> may differ from e.g. MUSIC/SP.
> 
> ABI means what? for those of us reading and trying to keep up ;) this 
> might even be something new to those attempting to work on such a port 
> task ;)

Application Binary Interface, it's the overall set of register usage 
conventions, syscall numbers and so on. I'm unsure the origin of the 
term but over the last ten years or so it's come into common usage for 
Linux, and extended to other OSes.

For Linux on IBM mainframes, see 
http://linuxvm.org/present/SHARE102/S9236uw.pdf as a starting point. 
Also I've put info on assembler formats etc. at 
http://wiki.lazarus.freepascal.org/Assembler_and_ABI_Resources (I needed 
comparative info when looking at MIPS a few months ago), I was hoping to 
add links to ABIs for each architecture but didn't get that far since 
something else intervened.

-- 
Mark Morgan Lloyd
markMLl .AT. telemetry.co .DOT. uk

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