[fpc-pascal]Default calling convention
tom_at_work at gmx.at
Fri Jul 2 19:31:30 CEST 2004
>>In this case
>> procedure nx_fill(P: PLongword; Count: Longint; Value: Longword);
>> pushl %edi
>> movl P,%edi // edi <- P
>> movl Value,%eax // eax <- Value
>> movl Count,%ecx // ecx <- Count
>> popl %edi
>>works both as embedded and non-embedded assembler procedure because the
>>order of assignments is ok in both cases.
> Yes, but this way a program becomes a mineland. You write this, a few
> weeks later, for some reason, you change the line order, and you waste
> time to find why, suddenly, your program crashes (and yet, assuming you
> immediately activate the bug).
:( That's true.
I usually add a 'pascal' procedure modifier to most (if not all)
assembler routines exactly because of that. This forces parameter
passing on the stack.
This is a little slower, but if your hand-coded assembler proc is only
faster if the parameters are passed through registers, it might be a
good idea to use Pascal right away...
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