VM Maker: VMMaker-oscog.33.mcz

Eliot

I wanted to understand what: '  Have various places check for isOopCOmpiledMethod:
rather than isCompiledMethod: to allow SmallIntegers to be used as methods.'
means
       in which circumstances do we want to have smalltalkIntegers used as methods?
       when we put an object instead of a compiled method and that by accident this is an integer?

Stef

>
>
> Name: VMMaker-oscog.33
> Author: eem
> Time: 25 September 2010, 7:13:51 am
> UUID: 733b7c50-b973-4ca0-9831-5c84d09032bf
> Ancestors: VMMaker-oscog.32
>
> OSCogVM:
>  Support object-as-method:
>       Eagerly evaluate the interpreter version of a primitive
>       to ease the object-as-method implementation and to
>       improve interpreter performance.
>       Refuse to enter anything that isn't a CompiledMethod
>       into the method-lookup cache to avoid open PICs having
>       to check for valid compiled methods.
>       Have various places check for isOopCOmpiledMethod:
>       rather than isCompiledMethod: to allow SmallIntegers to
>       be used as methods.
> Interpreter:
>       Have various places check for isOopCOmpiledMethod:
>       rather than isCompiledMethod: to allow SmallIntegers to
>       be used as methods.
> Slang:
>       support super sends by expanding them at translation
>       time.  This allows CoInterpreter>>addMethodToCache
>       to avoid cacheing non-compiled methods via a super
>       send, avoiding duplicating SrackInterpreter's method.
>

 

On Sun, Sep 26, 2010 at 1:45 PM, stephane ducasse <[hidden email]> wrote:

Eliot

I wanted to understand what: '  Have various places check for isOopCOmpiledMethod:
rather than isCompiledMethod: to allow SmallIntegers to be used as methods.'
means
       in which circumstances do we want to have smalltalkIntegers used as methods?
       when we put an object instead of a compiled method and that by accident this is an integer?

Eliot, first of all, thanks A LOT!!!  This is really important for us....wiiii we have TestCoverage again :)

BTW, I think I found something related to what Stef says....In normal squeakVM :

testAddNumbers
    self assert: (self add: 3 with: 4) = 7.
    self assert: (self perform: #add:with: withArguments: #(3 4)) = 7.

this is ok, since (self perform: #add:with: withArguments: #(3 4))  answers 7.
But with this new CogVM, there is a primitiveError.

so...we can update the test to:

    self should: (self perform: #add:with: withArguments: #(3 4)) rise: Error.

or something like that....but this test will fail with normal VM..

what we should do?

thanks

mariano
 

Stef

>
>
> Name: VMMaker-oscog.33
> Author: eem
> Time: 25 September 2010, 7:13:51 am
> UUID: 733b7c50-b973-4ca0-9831-5c84d09032bf
> Ancestors: VMMaker-oscog.32
>
> OSCogVM:
>  Support object-as-method:
>       Eagerly evaluate the interpreter version of a primitive
>       to ease the object-as-method implementation and to
>       improve interpreter performance.
>       Refuse to enter anything that isn't a CompiledMethod
>       into the method-lookup cache to avoid open PICs having
>       to check for valid compiled methods.
>       Have various places check for isOopCOmpiledMethod:
>       rather than isCompiledMethod: to allow SmallIntegers to
>       be used as methods.
> Interpreter:
>       Have various places check for isOopCOmpiledMethod:
>       rather than isCompiledMethod: to allow SmallIntegers to
>       be used as methods.
> Slang:
>       support super sends by expanding them at translation
>       time.  This allows CoInterpreter>>addMethodToCache
>       to avoid cacheing non-compiled methods via a super
>       send, avoiding duplicating SrackInterpreter's method.
>

Eliot

I wanted to understand what: '  Have various places check for isOopCOmpiledMethod:
rather than isCompiledMethod: to allow SmallIntegers to be used as methods.'
means
       in which circumstances do we want to have smalltalkIntegers used as methods?
       when we put an object instead of a compiled method and that by accident this is an integer?

Stef

>
>
> Name: VMMaker-oscog.33
> Author: eem
> Time: 25 September 2010, 7:13:51 am
> UUID: 733b7c50-b973-4ca0-9831-5c84d09032bf
> Ancestors: VMMaker-oscog.32
>
> OSCogVM:
>  Support object-as-method:
>       Eagerly evaluate the interpreter version of a primitive
>       to ease the object-as-method implementation and to
>       improve interpreter performance.
>       Refuse to enter anything that isn't a CompiledMethod
>       into the method-lookup cache to avoid open PICs having
>       to check for valid compiled methods.
>       Have various places check for isOopCOmpiledMethod:
>       rather than isCompiledMethod: to allow SmallIntegers to
>       be used as methods.
> Interpreter:
>       Have various places check for isOopCOmpiledMethod:
>       rather than isCompiledMethod: to allow SmallIntegers to
>       be used as methods.
> Slang:
>       support super sends by expanding them at translation
>       time.  This allows CoInterpreter>>addMethodToCache
>       to avoid cacheing non-compiled methods via a super
>       send, avoiding duplicating SrackInterpreter's method.
>

 

On Sun, Sep 26, 2010 at 5:59 AM, Mariano Martinez Peck <[hidden email]> wrote:

 

On Sun, Sep 26, 2010 at 1:45 PM, stephane ducasse <[hidden email]> wrote:

Eliot

I wanted to understand what: '  Have various places check for isOopCOmpiledMethod:
rather than isCompiledMethod: to allow SmallIntegers to be used as methods.'
means
       in which circumstances do we want to have smalltalkIntegers used as methods?
       when we put an object instead of a compiled method and that by accident this is an integer?

Eliot, first of all, thanks A LOT!!!  This is really important for us....wiiii we have TestCoverage again :)

BTW, I think I found something related to what Stef says....In normal squeakVM :

testAddNumbers
    self assert: (self add: 3 with: 4) = 7.
    self assert: (self perform: #add:with: withArguments: #(3 4)) = 7.

this is ok, since (self perform: #add:with: withArguments: #(3 4))  answers 7.
But with this new CogVM, there is a primitiveError.

so...we can update the test to:

    self should: (self perform: #add:with: withArguments: #(3 4)) rise: Error.

or something like that....but this test will fail with normal VM..

what we should do?

Leave the test be.  The test should not fail.  I should fix Cog.  Now I have the difficult part done fixing related should not take as long.

But I don't see this failure in the Squeak tests.  Can you email me the Pharo version of Tests-ObjectsAsMethods?

TIA

 

thanks

mariano
 

Stef

>
>
> Name: VMMaker-oscog.33
> Author: eem
> Time: 25 September 2010, 7:13:51 am
> UUID: 733b7c50-b973-4ca0-9831-5c84d09032bf
> Ancestors: VMMaker-oscog.32
>
> OSCogVM:
>  Support object-as-method:
>       Eagerly evaluate the interpreter version of a primitive
>       to ease the object-as-method implementation and to
>       improve interpreter performance.
>       Refuse to enter anything that isn't a CompiledMethod
>       into the method-lookup cache to avoid open PICs having
>       to check for valid compiled methods.
>       Have various places check for isOopCOmpiledMethod:
>       rather than isCompiledMethod: to allow SmallIntegers to
>       be used as methods.
> Interpreter:
>       Have various places check for isOopCOmpiledMethod:
>       rather than isCompiledMethod: to allow SmallIntegers to
>       be used as methods.
> Slang:
>       support super sends by expanding them at translation
>       time.  This allows CoInterpreter>>addMethodToCache
>       to avoid cacheing non-compiled methods via a super
>       send, avoiding duplicating SrackInterpreter's method.
>

should I conclude that before your change even the default old vm would crash when we put a SmallInteger in a methodDict?

Because if I would have know I would not ask my question. I thought it was for something else you had in mind.

Stef

>
> Eliot
>
> I wanted to understand what: '  Have various places check for isOopCOmpiledMethod:
> rather than isCompiledMethod: to allow SmallIntegers to be used as methods.'
> means
>        in which circumstances do we want to have smalltalkIntegers used as methods?
>        when we put an object instead of a compiled method and that by accident this is an integer?
>
> Looking at the code for the standard Interpreter, if anyone tried
>
>     self class addSelector: #foo withMethod: 0.
>     self foo.
>
> then the VM would crash trying to determine if 0 was a compiled method because the VM uses isCompiledMethod: and isCompiledMethod: does not (and should not, because it is used elsewhere) guard against a tagged object.  isOopCompiledMethod: does guard against a tagged object:
>
> isOopCompiledMethod: oop
>     ^(self isNonIntegerObject: oop) and: [self isCompiledMethod: oop]
>
> isCompiledMethod: obj
>     ^(self formatOf: obj) >= 12
>
> So in practice it's not an issue; presumably no-one is using SmallIntegers as methods ("Doctor it hurts when I...").  But if the VM provides a facility it is nice for it to provide that facility robustly (if there is no significant impact on performance).
>
>