> On Mon, Jan 23, 2012 at 8:52 AM, Mariano Martinez Peck <
marianopeck@gmail.com> wrote:
> Hi guys. I usually like to take a look to ProtoObject and see what is really needed for the minimal object. But having 30% of the methods being #tryNamedPrimitive:with: * is not fun.
> So...I wonder, do you think there could be another way so that to avoid having all those methods in ProtoObject ?
>
> Yes there is. I implemented primitive 218 in Cog, primitiveDoNamedPrimitiveWithArgs, which is accessed via
>
>
> tryNamedPrimitiveIn: aCompiledMethod for: aReceiver withArgs: arguments
> | selector theMethod spec receiverClass |
> <primitive: 218 error: ec>
> ec ifNotNil:
> ["If ec is an integer other than -1 there was a problem with primitive 218,
> not with the external primitive itself. -1 indicates a generic failure (where
> ec should be nil) but ec = nil means primitive 218 is not implemented. So
> interpret -1 to mean the external primitive failed with a nil error code."
> ec isInteger ifTrue:
> [ec = -1
> ifTrue: [ec := nil]
> ifFalse: [self primitiveFailed]].
> ^{PrimitiveFailToken. ec}].
> "Assume a nil error code implies the primitive is not implemented and fall back on the old code."
> "Hack. Attempt to execute the named primitive from the given compiled method"
> arguments size > 8 ifTrue:
> [^{PrimitiveFailToken. nil}].
> selector := #(
> tryNamedPrimitive
> tryNamedPrimitive:
> tryNamedPrimitive:with:
> tryNamedPrimitive:with:with:
> tryNamedPrimitive:with:with:with:
> tryNamedPrimitive:with:with:with:with:
> tryNamedPrimitive:with:with:with:with:with:
> tryNamedPrimitive:with:with:with:with:with:with:
> tryNamedPrimitive:with:with:with:with:with:with:with:) at: arguments size+1.
> receiverClass := self objectClass: aReceiver.
> theMethod := receiverClass lookupSelector: selector.
> theMethod == nil ifTrue:
> [^{PrimitiveFailToken. nil}].
> spec := theMethod literalAt: 1.
> spec replaceFrom: 1 to: spec size with: (aCompiledMethod literalAt: 1) startingAt: 1.
> Smalltalk unbindExternalPrimitives.
> ^self object: aReceiver perform: selector withArguments: arguments inClass: receiverClass
>
> (cf tryPrimitive: withArgs:) and used in
>
>
> doPrimitive: primitiveIndex method: meth receiver: receiver args: arguments
> "Simulate a primitive method whose index is primitiveIndex. The simulated receiver
> and arguments are given as arguments to this message. Any primitive which provokes
> execution needs to be intercepted and simulated to avoid execution running away."
>
> | value |
> "If successful, push result and return resuming context, else ^ { PrimitiveFailToken. errorCode }"
> (primitiveIndex = 19) ifTrue:
> [ToolSet
> debugContext: self
> label:'Code simulation error'
> contents: nil].
>
> "ContextPart>>blockCopy:; simulated to get startpc right"
> (primitiveIndex = 80 and: [(self objectClass: receiver) includesBehavior: ContextPart])
> ifTrue: [^self push: ((BlockContext newForMethod: receiver method)
> home: receiver home
> startpc: pc + 2
> nargs: (arguments at: 1))].
> (primitiveIndex = 81 and: [(self objectClass: receiver) == BlockContext]) "BlockContext>>value[:value:...]"
> ifTrue: [^receiver pushArgs: arguments from: self].
> (primitiveIndex = 82 and: [(self objectClass: receiver) == BlockContext]) "BlockContext>>valueWithArguments:"
> ifTrue: [^receiver pushArgs: arguments first from: self].
> primitiveIndex = 83 "afr 9/11/1998 19:50" "Object>>perform:[with:...]"
> ifTrue: [^self send: arguments first
> to: receiver
> with: arguments allButFirst
> super: false].
> primitiveIndex = 84 "afr 9/11/1998 19:50 & eem 8/18/2009 17:04" "Object>>perform:withArguments:"
> ifTrue: [^self send: arguments first
> to: receiver
> with: (arguments at: 2)
> startClass: nil].
> primitiveIndex = 100 "eem 8/18/2009 16:57" "Object>>perform:withArguments:inSuperclass:"
> ifTrue: [^self send: arguments first
> to: receiver
> with: (arguments at: 2)
> startClass: (arguments at: 3)].
>
> "Mutex>>primitiveEnterCriticalSection
> Mutex>>primitiveTestAndSetOwnershipOfCriticalSection"
> (primitiveIndex = 186 or: [primitiveIndex = 187]) ifTrue:
> [| active effective |
> active := Processor activeProcess.
> effective := active effectiveProcess.
> "active == effective"
> value := primitiveIndex = 186
> ifTrue: [receiver primitiveEnterCriticalSectionOnBehalfOf: effective]
> ifFalse: [receiver primitiveTestAndSetOwnershipOfCriticalSectionOnBehalfOf: effective].
> ^(value isArray
> and: [value size = 2
> and: [value first == PrimitiveFailToken]])
> ifTrue: [value]
> ifFalse: [self push: value]].
>
> primitiveIndex = 188 ifTrue: "eem 5/27/2008 11:10 Object>>withArgs:executeMethod:"
> [^MethodContext
> sender: self
> receiver: receiver
> method: (arguments at: 2)
> arguments: (arguments at: 1)].
>
> "Closure primitives"
> (primitiveIndex = 200 and: [self == receiver]) ifTrue:
> "ContextPart>>closureCopy:copiedValues:; simulated to get startpc right"
> [^self push: (BlockClosure
> outerContext: receiver
> startpc: pc + 2
> numArgs: arguments first
> copiedValues: arguments last)].
> ((primitiveIndex between: 201 and: 205) "BlockClosure>>value[:value:...]"
> or: [primitiveIndex between: 221 and: 222]) ifTrue: "BlockClosure>>valueNoContextSwitch[:]"
> [^receiver simulateValueWithArguments: arguments caller: self].
> primitiveIndex = 206 ifTrue: "BlockClosure>>valueWithArguments:"
> [^receiver simulateValueWithArguments: arguments first caller: self].
>
> primitiveIndex = 118 ifTrue: "tryPrimitive:withArgs:; avoid recursing in the VM"
> [(arguments size = 2
> and: [arguments first isInteger
> and: [arguments last class == Array]]) ifFalse:
> [^ContextPart primitiveFailTokenFor: nil].
> ^self doPrimitive: arguments first method: meth receiver: receiver args: arguments last].
>
> value := primitiveIndex = 120 "FFI method"
> ifTrue: [(meth literalAt: 1) tryInvokeWithArguments: arguments]
> ifFalse:
> [primitiveIndex = 117 "named primitives"
> ifTrue: [self tryNamedPrimitiveIn: meth for: receiver withArgs: arguments]
> ifFalse:
> [receiver tryPrimitive: primitiveIndex withArgs: arguments]].
> ^(value isArray
> and: [value size = 2
> and: [value first == PrimitiveFailToken]])
> ifTrue: [value]
> ifFalse: [self push: value]
>
> (find attached). But these need implementing in the standard VM before they can be used in Pharo, Squeak, etc.
>
>
> Thanks
>
> --
> Mariano
>
http://marianopeck.wordpress.com
>
>
>
>
> --
> best,
> Eliot
>