[Vm-dev] Lowcode and x64

[Nicolas Cellier]

Hi Ronie,
>From my understanding, following code cannot work in x64 because registers
are overwritten while marshalling arguments:

generateLowcodeObjectTrampolines
    ... snip ...
    ceInstantiateClassIndexableSizeTrampoline := cogit genTrampolineFor:
#instantiateClass:indexableSize:
                                                called:
'ceInstantiateClassIndexableSizeTrampoline'
                                                arg: ReceiverResultReg
                                                arg: Arg0Reg
                                                result: TempReg.

The first arg ReceiverResultReg (RDX) will overwrite Arg0Reg (RDI) before
Arg0Reg is copied to Arg1Reg (RSI)...
See genMarshallNArgs:arg:arg:arg:arg:
and carefully read the comment for the x64 flavour, it's scary ;)

Cheers
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