Hi, Magritte and my TagLengthValue (TLV) both use >>#instVarNamed:/>>#instVarNamed:put: to read and write from an object. I was just running >>#bench on my SMPP library and noticed that besides Spur Pharo5 is slower than Pharo3. I added this to PointerLayout:
# instVarIndexFor: aString ifAbsent: aBlockClosure | idx | idx := 1. slotScope do: [:each | each isVisible ifTrue: [ each name = aString ifTrue: [^idx]. idx := idx +1]]. ^aBlockClosure value
and modified ClassDescription/TClassDescription to use it: "protocol: instance variables" instVarIndexFor: instVarName ifAbsent: aBlock "Answer the index of the named instance variable." | index | index := self classLayout instVarIndexFor: instVarName ifAbsent: [0]. index = 0 ifTrue: [^self superclass == nil ifTrue: [aBlock value] ifFalse: [self superclass instVarIndexFor: instVarName ifAbsent: aBlock]]. ^self superclass == nil ifTrue: [index] ifFalse: [index + self superclass instSize] The speed-up comes from filtering allSlots to allVisibleSlots (and creating an Array), then collecting the slot names and finally searching the name. Does it make sense to integrate such speed-ups? cheers holger