[Vm-dev] Weird problem when adding a method to StackInterpreter

[Mariano Martinez Peck]

>
>>
>> Moreover, when I ADD those lines, apart from the make error, when
>> translating from SLANG to C, if I open a Transcript I see these
>> "suspicious" lines:
>>
>> Removed findNewMethodInClass: because it refers to the local variable
>> localSP of interpret.
>> But it is either used outside of interpret or exported!!
>> Removed lookupInMethodCacheSel:class: because it refers to the local
>> variable localSP of interpret.
>> But it is either used outside of interpret or exported!!
>>
>> BUT, none of those methods access localSP.
>>
>> Any idea of what can be wrong?
>>
>
> For some reason  lookupInMethodCacheSel:class: is not being inlined.
>  Since it uses localSP via internalStackValue: it must be always inlined
> into the body of interpret.  What I don't know is why adding a send of
> traceObjectusage: after internalStackValue: causes inlining to fail.
>


Hi Eliot. I did some more tests and it even fails WITHOUT using
#traceObjectUsage:  .  Just adding the line "rcvr := self
internalStackValue: argumentCount."  at the beginning of
#lookupInMethodCacheSel:class:   will cause the problem. So, the following
even fails:

lookupInMethodCacheSel: selector class: class
    "This method....."

    | hash probe rcvr |
    <inline: true>
    <asmLabel: false>
    rcvr := self internalStackValue: argumentCount.
    hash := selector bitXor: class.  "shift drops two low-order zeros from
addresses"
......


Weird ehh, because you use #internalStackValue:  along StackInterpreter in
a lot of other places and you don't have problems there.



>  You're going to have to delve into the inliner in Slang.  This is, um,
> not fun.  I liken it to getting hit on the head with a stick by your guru,
> except that no enlightenment results.  Good luck.
>
>
:(   thanks.



>
>> Thanks in advance,
>>
>>
>> --
>> Mariano
>> http://marianopeck.wordpress.com
>>
>>
>>
>
>
> --
> best,
> Eliot
>
>
>


-- 
Mariano
http://marianopeck.wordpress.com
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