Squeak-dev October 2014

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The Trunk: Network-ul.155.mcz
by commits＠source.squeak.org 27 Oct '14

27 Oct '14

Levente Uzonyi uploaded a new version of Network to project The Trunk: http://source.squeak.org/trunk/Network-ul.155.mcz ==================== Summary ==================== Name: Network-ul.155 Author: ul Time: 27 October 2014, 4:46:13.635 pm UUID: cf2f8a25-3525-4183-8f93-7dc5d127f22d Ancestors: Network-ul.152 - use the new ExternalObjectTable API - unifed socket initialization - unregister ResolverSemaphore when the network initialization fails =============== Diff against Network-ul.152 =============== Item was changed: ----- Method: NetNameResolver class>>initializeNetwork (in category 'network initialization') ----- initializeNetwork "Initialize the network drivers and record the semaphore to be used by the resolver. Do nothing if the network is already initialized. Evaluate the given block if network initialization fails." "NetNameResolver initializeNetwork" - | semaIndex | self resolverStatus = ResolverUninitialized ifFalse: [^HaveNetwork := true]. "network is already initialized" HaveNetwork := false. "in case abort" + Smalltalk newExternalSemaphoreDo: [ :semaphore :index | + ResolverSemaphore := semaphore. + "result is nil if network initialization failed, self if it succeeds" + (self primInitializeNetwork: index) + ifNil: [ + Smalltalk unregisterExternalObject: ResolverSemaphore. + ResolverSemaphore := nil. + NoNetworkError signal: 'failed network initialization'] + ifNotNil: [ HaveNetwork := true ] ]. - ResolverSemaphore := Semaphore new. - semaIndex := Smalltalk registerExternalObject: ResolverSemaphore. + self initializeOldNetworkFlag! - "result is nil if network initialization failed, self if it succeeds" - (self primInitializeNetwork: semaIndex) - ifNil: [NoNetworkError signal: 'failed network initialization'] - ifNotNil: [HaveNetwork := true]. - - self initializeOldNetworkFlag - ! Item was changed: ----- Method: Socket>>acceptFrom: (in category 'initialize-destroy') ----- acceptFrom: aSocket "Initialize a new socket handle from an accept call" - | semaIndex readSemaIndex writeSemaIndex | + self initializeSocketHandleUsing: [ :semaIndex :readSemaIndex :writeSemaIndex | + self + primAcceptFrom: aSocket socketHandle + receiveBufferSize: 8000 + sendBufSize: 8000 + semaIndex: semaIndex + readSemaIndex: readSemaIndex + writeSemaIndex: writeSemaIndex ]! - semaphore := Semaphore new. - readSemaphore := Semaphore new. - writeSemaphore := Semaphore new. - semaIndex := Smalltalk registerExternalObject: semaphore. - readSemaIndex := Smalltalk registerExternalObject: readSemaphore. - writeSemaIndex := Smalltalk registerExternalObject: writeSemaphore. - socketHandle := self primAcceptFrom: aSocket socketHandle - receiveBufferSize: 8000 - sendBufSize: 8000 - semaIndex: semaIndex - readSemaIndex: readSemaIndex - writeSemaIndex: writeSemaIndex. - socketHandle - ifNotNil: [ self register ] - ifNil: [ "socket creation failed" - Smalltalk unregisterExternalObject: semaphore. - Smalltalk unregisterExternalObject: readSemaphore. - Smalltalk unregisterExternalObject: writeSemaphore. - readSemaphore := writeSemaphore := semaphore := nil ] - ! Item was changed: ----- Method: Socket>>destroy (in category 'initialize-destroy') ----- destroy "Destroy this socket. Its connection, if any, is aborted and its resources are freed. Do nothing if the socket has already been destroyed (i.e., if its socketHandle is nil)." socketHandle ifNotNil: [ self isValid ifTrue: [ self primSocketDestroy: socketHandle ]. + Smalltalk unregisterExternalObjects: { + semaphore. + readSemaphore. + writeSemaphore }. - Smalltalk unregisterExternalObject: semaphore. - Smalltalk unregisterExternalObject: readSemaphore. - Smalltalk unregisterExternalObject: writeSemaphore. socketHandle := nil. readSemaphore := writeSemaphore := semaphore := nil. self unregister ]! Item was changed: ----- Method: Socket>>finalize (in category 'finalization') ----- finalize + self primSocketDestroyGently: socketHandle. + Smalltalk unregisterExternalObjects: { + semaphore. + readSemaphore. + writeSemaphore } - Smalltalk unregisterExternalObject: semaphore. - Smalltalk unregisterExternalObject: readSemaphore. - Smalltalk unregisterExternalObject: writeSemaphore. ! Item was changed: ----- Method: Socket>>initialize: (in category 'initialize-destroy') ----- initialize: socketType "Initialize a new socket handle. If socket creation fails, socketHandle will be set to nil." - | semaIndex readSemaIndex writeSemaIndex | + self initializeSocketHandleUsing: [ :semaIndex :readSemaIndex :writeSemaIndex | - semaphore := Semaphore new. - readSemaphore := Semaphore new. - writeSemaphore := Semaphore new. - semaIndex := Smalltalk registerExternalObject: semaphore. - readSemaIndex := Smalltalk registerExternalObject: readSemaphore. - writeSemaIndex := Smalltalk registerExternalObject: writeSemaphore. - socketHandle := self primSocketCreateNetwork: 0 type: socketType receiveBufferSize: 8000 sendBufSize: 8000 semaIndex: semaIndex readSemaIndex: readSemaIndex + writeSemaIndex: writeSemaIndex ]! - writeSemaIndex: writeSemaIndex. - - socketHandle - ifNotNil: [ self register ] - ifNil: [ "socket creation failed" - Smalltalk unregisterExternalObject: semaphore. - Smalltalk unregisterExternalObject: readSemaphore. - Smalltalk unregisterExternalObject: writeSemaphore. - readSemaphore := writeSemaphore := semaphore := nil ] - ! Item was changed: ----- Method: Socket>>initialize:family: (in category 'initialize-destroy') ----- initialize: socketType family: family "Initialize a new socket handle. If socket creation fails, socketHandle will be set to nil." - | semaIndex readSemaIndex writeSemaIndex | + NetNameResolver useOldNetwork ifTrue: [ ^self initialize: socketType ]. + self initializeSocketHandleUsing: [ :semaIndex :readSemaIndex :writeSemaIndex | - NetNameResolver useOldNetwork ifTrue: [^self initialize: socketType]. - semaphore := Semaphore new. - readSemaphore := Semaphore new. - writeSemaphore := Semaphore new. - semaIndex := Smalltalk registerExternalObject: semaphore. - readSemaIndex := Smalltalk registerExternalObject: readSemaphore. - writeSemaIndex := Smalltalk registerExternalObject: writeSemaphore. - socketHandle := self primSocketCreateNetwork: family type: socketType receiveBufferSize: 8000 sendBufSize: 8000 semaIndex: semaIndex readSemaIndex: readSemaIndex + writeSemaIndex: writeSemaIndex ]! - writeSemaIndex: writeSemaIndex. - - socketHandle - ifNotNil: [ self register ] - ifNil: [ "socket creation failed" - Smalltalk unregisterExternalObject: semaphore. - Smalltalk unregisterExternalObject: readSemaphore. - Smalltalk unregisterExternalObject: writeSemaphore. - readSemaphore := writeSemaphore := semaphore := nil ] - ! Item was added: + ----- Method: Socket>>initializeSocketHandleUsing: (in category 'initialize-destroy') ----- + initializeSocketHandleUsing: aBlock + "Initialize a new socket handle. If socket creation fails, socketHandle will be set to nil." + + | semaphoresAndIndexes semaphores indexes | + semaphoresAndIndexes := Smalltalk newExternalSemaphores: 3. + semaphores := semaphoresAndIndexes at: 1. + indexes := semaphoresAndIndexes at: 2. + semaphore := semaphores at: 1. + readSemaphore := semaphores at: 2. + writeSemaphore := semaphores at: 3. + (socketHandle := aBlock valueWithArguments: indexes) + ifNotNil: [ self register ] + ifNil: [ + "socket creation failed" + semaphore := readSemaphore := writeSemaphore := nil. + Smalltalk unregisterExternalObjects: semaphores ]!

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The Trunk: Files-ul.141.mcz
by commits＠source.squeak.org 27 Oct '14

27 Oct '14

Levente Uzonyi uploaded a new version of Files to project The Trunk: http://source.squeak.org/trunk/Files-ul.141.mcz ==================== Summary ==================== Name: Files-ul.141 Author: ul Time: 27 October 2014, 4:51:14.305 pm UUID: b0dbabfe-ce75-4f18-a82f-2f95fa8b026e Ancestors: Files-eem.138 - use the new ExternalObjectTable API =============== Diff against Files-eem.138 =============== Item was changed: ----- Method: AsyncFile>>open:forWrite: (in category 'as yet unclassified') ----- open: fullFileName forWrite: aBoolean "Open a file of the given name, and return a handle for that file. Answer the receiver if the primitive succeeds, nil otherwise. If openForWrite is true, then: if there is no existing file with this name, then create one else open the existing file in read-write mode otherwise: if there is an existing file with this name, then open it read-only else answer nil." "Note: if an exisiting file is opened for writing, it is NOT truncated. If truncation is desired, the file should be deleted before being opened as an asynchronous file." "Note: On some platforms (e.g., Mac), a file can only have one writer at a time." - | semaIndex | name := fullFileName. writeable := aBoolean. + ^Smalltalk newExternalSemaphoreDo: [ :newSemaphore :index | + fileHandle := self primOpen: name asVmPathName forWrite: writeable semaIndex: index. + fileHandle + ifNotNil: [ + semaphore := newSemaphore. + self ] + ifNil: [ + Smalltalk unregisterExternalObject: newSemaphore. + nil ] ]! - semaphore := Semaphore new. - semaIndex := Smalltalk registerExternalObject: semaphore. - fileHandle := self primOpen: name asVmPathName forWrite: writeable semaIndex: semaIndex. - fileHandle ifNil: [ - Smalltalk unregisterExternalObject: semaphore. - semaphore := nil. - ^ nil]. - ! Item was changed: ----- Method: StandardFileStream>>post:target:url:ifError: (in category 'browser requests') ----- post: data target: target url: url ifError: errorBlock "Post data to the given URL. The returned file stream contains the reply of the server. If Squeak is not running in a browser evaluate errorBlock" + - | sema index request result | self waitBrowserReadyFor: self defaultBrowserReadyWait ifFail: [^errorBlock value]. + Smalltalk newExternalSemaphoreDo: [ :semaphore :index | + | request result | + request := self primURLPost: url target: target data: data semaIndex: index. + request ifNil: [ + Smalltalk unregisterExternalObject: semaphore. + ^errorBlock value ]. + [ semaphore wait. "until something happens" + result := self primURLRequestState: request. + result == nil ] whileTrue. + result ifTrue: [ fileID := self primURLRequestFileHandle: request ]. - sema := Semaphore new. - index := Smalltalk registerExternalObject: sema. - request := self primURLPost: url target: target data: data semaIndex: index. - request == nil ifTrue:[ - - Smalltalk unregisterExternalObject: sema. - ^errorBlock value. - ] ifFalse:[ - [sema wait. "until something happens" - result := self primURLRequestState: request. - result == nil] whileTrue. - result ifTrue:[fileID := self primURLRequestFileHandle: request]. self primURLRequestDestroy: request. + Smalltalk unregisterExternalObject: semaphore ]. + fileID ifNil: [ ^nil ]. - ]. - Smalltalk unregisterExternalObject: sema. - fileID == nil ifTrue:[^nil]. self register. name := url. rwmode := false. buffer1 := String new: 1. + self enableReadBuffering! - self enableReadBuffering - ! Item was changed: ----- Method: StandardFileStream>>requestURL:target:ifError: (in category 'browser requests') ----- requestURL: url target: target ifError: errorBlock "Request to go to the target for the given URL. If Squeak is not running in a browser evaluate errorBlock" - | sema index request result | self waitBrowserReadyFor: self defaultBrowserReadyWait ifFail: [^errorBlock value]. + Smalltalk newExternalSemaphoreDo: [ :semaphore :index | + | request result | + request := self primURLRequest: url target: target semaIndex: index. + request ifNil: [ + Smalltalk unregisterExternalObject: semaphore. + ^errorBlock value ]. + [ semaphore wait. "until something happens" + result := self primURLRequestState: request. + result == nil ] whileTrue. - sema := Semaphore new. - index := Smalltalk registerExternalObject: sema. - request := self primURLRequest: url target: target semaIndex: index. - request == nil ifTrue:[ - - Smalltalk unregisterExternalObject: sema. - ^errorBlock value. - ] ifFalse:[ - [sema wait. "until something happens" - result := self primURLRequestState: request. - result == nil] whileTrue. self primURLRequestDestroy: request. + Smalltalk unregisterExternalObject: semaphore ]. + fileID ifNil: [ ^nil ]. - ]. - Smalltalk unregisterExternalObject: sema. - fileID == nil ifTrue:[^nil]. self register. name := url. rwmode := false. buffer1 := String new: 1. + self enableReadBuffering! - self enableReadBuffering - ! Item was changed: ----- Method: StandardFileStream>>requestURLStream:ifError: (in category 'browser requests') ----- requestURLStream: url ifError: errorBlock "Request a FileStream for the given URL. If Squeak is not running in a browser evaluate errorBlock" "FileStream requestURLStream:'http://www.squeak.org'" + - | sema index request result | self waitBrowserReadyFor: self defaultBrowserReadyWait ifFail: [^errorBlock value]. + Smalltalk newExternalSemaphoreDo: [ :semaphore :index | + | request result | + request := self primURLRequest: url semaIndex: index. + request ifNil: [ + Smalltalk unregisterExternalObject: semaphore. + ^errorBlock value ]. + [ semaphore wait. "until something happens" + result := self primURLRequestState: request. + result == nil ] whileTrue. + result ifTrue: [ fileID := self primURLRequestFileHandle: request ]. - sema := Semaphore new. - index := Smalltalk registerExternalObject: sema. - request := self primURLRequest: url semaIndex: index. - request == nil ifTrue:[ - - Smalltalk unregisterExternalObject: sema. - ^errorBlock value. - ] ifFalse:[ - [sema wait. "until something happens" - result := self primURLRequestState: request. - result == nil] whileTrue. - result ifTrue:[fileID := self primURLRequestFileHandle: request]. self primURLRequestDestroy: request. + Smalltalk unregisterExternalObject: semaphore ]. + fileID ifNil: [ ^nil ]. - ]. - Smalltalk unregisterExternalObject: sema. - fileID == nil ifTrue:[^nil]. self register. name := url. rwmode := false. buffer1 := String new: 1. + self enableReadBuffering! - self enableReadBuffering - !

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Re: [squeak-dev] The Trunk: KernelTests-nice.280.mcz
by Nicolas Cellier 27 Oct '14

27 Oct '14

Once upon a Time, there could have been a literal nan... Yes, in Squeak 3.8 or 3.9 when formed thru ('0.' , (String new: 320 withAll: $0) , '1e321') - see http://bugs.squeak.org/view.php?id=6982 Let's consider this case rare and accidental... Now, even if literalEqualityOfNan is a bit like unreachable, let's consider this as a future proof test... 2014-10-27 21:53 GMT+01:00 <commits(a)source.squeak.org>: > Nicolas Cellier uploaded a new version of KernelTests to project The Trunk: > http://source.squeak.org/trunk/KernelTests-nice.280.mcz > > ==================== Summary ==================== > > Name: KernelTests-nice.280 > Author: nice > Time: 27 October 2014, 9:53:44.861 pm > UUID: fc50e9f5-10d8-45d8-8c9e-e80806596878 > Ancestors: KernelTests-dtl.279 > > Two more expectations for float literal equality: > - zero and negativeZero are equal but not #literalEqual: > - nan are not equals but can be #literalEqual: > > Thanks to Kris Gybels for reporting this case at > https://pharo.fogbugz.com/f/cases/14316/ > > =============== Diff against KernelTests-dtl.279 =============== > > Item was added: > + ----- Method: FloatTest>>testLiteralEqualityOfNan (in category 'testing > compare') ----- > + testLiteralEqualityOfNan > + | nan | > + nan := Float nan. > + self assert: (nan literalEqual: nan) > + description: 'Float nan is not equal to itself, though it > is literally equal'.! > > Item was added: > + ----- Method: FloatTest>>testLiteralEqualityOfZeroAndNegativeZero (in > category 'testing compare') ----- > + testLiteralEqualityOfZeroAndNegativeZero > + self assert: -1 > + equals: (Compiler evaluate: '1>2 ifTrue: [0.0] ifFalse: > [-0.0]') sign > + description: 'Float zero and negativeZero are not > literally substituable'.! > > >

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The Trunk: Kernel-nice.881.mcz
by commits＠source.squeak.org 27 Oct '14

27 Oct '14

Nicolas Cellier uploaded a new version of Kernel to project The Trunk: http://source.squeak.org/trunk/Kernel-nice.881.mcz ==================== Summary ==================== Name: Kernel-nice.881 Author: nice Time: 27 October 2014, 9:59:32.033 pm UUID: 3a3a0a22-ab12-4838-8606-250c9e58cf76 Ancestors: Kernel-ul.880 Fix Float literal equality: 0.0 and -0.0 are not the same Float... =============== Diff against Kernel-ul.880 =============== Item was added: + ----- Method: Float>>literalEqual: (in category 'comparing') ----- + literalEqual: aFloat + "Two float literals can be replaced by a single one only if their representation have the same bits. + For example, zero and negativeZero are equal, but not literally equal." + + ^self class == aFloat class and: [(self at: 1) = (aFloat at: 1) and: [(self at: 2) = (aFloat at: 2)]]!

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The Trunk: KernelTests-nice.280.mcz
by commits＠source.squeak.org 27 Oct '14

27 Oct '14

Nicolas Cellier uploaded a new version of KernelTests to project The Trunk: http://source.squeak.org/trunk/KernelTests-nice.280.mcz ==================== Summary ==================== Name: KernelTests-nice.280 Author: nice Time: 27 October 2014, 9:53:44.861 pm UUID: fc50e9f5-10d8-45d8-8c9e-e80806596878 Ancestors: KernelTests-dtl.279 Two more expectations for float literal equality: - zero and negativeZero are equal but not #literalEqual: - nan are not equals but can be #literalEqual: Thanks to Kris Gybels for reporting this case at https://pharo.fogbugz.com/f/cases/14316/ =============== Diff against KernelTests-dtl.279 =============== Item was added: + ----- Method: FloatTest>>testLiteralEqualityOfNan (in category 'testing compare') ----- + testLiteralEqualityOfNan + | nan | + nan := Float nan. + self assert: (nan literalEqual: nan) + description: 'Float nan is not equal to itself, though it is literally equal'.! Item was added: + ----- Method: FloatTest>>testLiteralEqualityOfZeroAndNegativeZero (in category 'testing compare') ----- + testLiteralEqualityOfZeroAndNegativeZero + self assert: -1 + equals: (Compiler evaluate: '1>2 ifTrue: [0.0] ifFalse: [-0.0]') sign + description: 'Float zero and negativeZero are not literally substituable'.!

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The Trunk: System-ul.688.mcz
by commits＠source.squeak.org 27 Oct '14

27 Oct '14

Levente Uzonyi uploaded a new version of System to project The Trunk: http://source.squeak.org/trunk/System-ul.688.mcz ==================== Summary ==================== Name: System-ul.688 Author: ul Time: 27 October 2014, 4:43:14.279 pm UUID: 77747387-55a5-4118-95b5-752979bf1cf7 Ancestors: System-dtl.685 Replaced ExternalSemaphoreTable with ExternalObjectTable to provide faster registration, and give better support to the current users of external objects. Notable changes: - the table is a separate object instead of a few class side methods - the whole API can be found in SmalltalkImage in the external objects category - #newExternalSemaphore, #newExternalSemaphoreDo: and #newExternalSemaphores: provide fast and easy creation and registration of Semaphores - #unregisterExternalObjects: can unregister multiple objects faster - #externalObjects will return a copy of the externalObjectsArray - better scalability - the maxExternalSemaphores VM parameter will be incremented as the externalObjectsArray grows =============== Diff against System-dtl.685 =============== Item was added: + Object subclass: #ExternalObjectTable + instanceVariableNames: 'semaphore externalObjectsArray freeSlotIndexes indexesByObjects' + classVariableNames: '' + poolDictionaries: '' + category: 'System-Support'! + ExternalObjectTable class + instanceVariableNames: 'current'! + + !ExternalObjectTable commentStamp: 'ul 10/27/2014 16:26' prior: 0! + I'm an enhanced version of JMM's ExternalSemaphoreTable. + I'm responsible for maintaining the externalObjectsArray, which can be found at slot 39 of Smalltalk specialObjectsArray. Manipulating the array directly is highly discouraged. + + My services are available via the methods of the "external objects" category of SmalltalkImage. + + To register anObject simply use Smalltalk registerExternalObject: anObject. Use #unregisterExternalObject: to unregister it. It your responsibility to always unregister these objects. + If you'd like the create one or more new Semaphores, and register them for external use, then you should use one of #newExternalSemaphore, #newExternalSemaphoreDo: and #newExternalSemaphores:. If you want to unregister more than one external objects at the same time, then #unregisterExternalObjects: is the method you're looking for. + + Implementation details: + I maintain a single instance (#current), which can automatically synchronize with externalObjectsArray. + All accesses are protected by the semaphore instance variable. + To ensure fast access, I keep track of the indexes of the external objects in the externalObjectArray in my indexesByObjects IdentityDictionary. + To ensure fast insertion, I keep track of the free slots of the externalObjectsArray in the freeSlotIndexes OrderedCollection. The access pattern is LIFO to avoid unnecessary growth and reordering of the OrderedCollection. + I can grow the externalObjectsArray (see #ensureFreeSlot), but I never shrink it.! + ExternalObjectTable class + instanceVariableNames: 'current'! Item was added: + ----- Method: ExternalObjectTable class>>cleanUp: (in category 'initialize-release') ----- + cleanUp: aggressive + "It's safe to release the instance" + + self reset! Item was added: + ----- Method: ExternalObjectTable class>>current (in category 'accessing') ----- + current + + ^current ifNil: [ + | newInstance | + newInstance := self new. + " Check again, because another process might have registered another instance. " + current ifNil: [ current := newInstance ] ]! Item was added: + ----- Method: ExternalObjectTable class>>reset (in category 'accessing') ----- + reset + + current := nil! Item was added: + ----- Method: ExternalObjectTable>>clearExternalObjects (in category 'accessing') ----- + clearExternalObjects + "Clear the array of objects that have been registered for use in non-Smalltalk code." + + semaphore critical: [ + Smalltalk specialObjectsArray at: 39 put: Array new. + self + initializeCaches; + synchronizeExternalObjectsArrayAndForceUpdate: true ]! Item was added: + ----- Method: ExternalObjectTable>>ensureFreeSlot (in category 'private') ----- + ensureFreeSlot + "Make sure there's at least one free slot." + + | oldSize newSize newExternalObjectsArray specialObjectsArray | + freeSlotIndexes isEmpty ifFalse: [ ^self ]. + oldSize := externalObjectsArray size. + newSize := oldSize + 20. "Linear growth is not really a problem, because we never shrink the array." + newExternalObjectsArray := externalObjectsArray species new: newSize. + newExternalObjectsArray + replaceFrom: 1 + to: oldSize + with: externalObjectsArray + startingAt: 1. + specialObjectsArray := Smalltalk specialObjectsArray. + (specialObjectsArray at: 39) == externalObjectsArray + ifFalse: [ + "We're not in sync. Try again." + ^self + synchronizeExternalObjectsArrayAndForceUpdate: true; + ensureFreeSlot ]. + specialObjectsArray at: 39 put: newExternalObjectsArray. + externalObjectsArray := newExternalObjectsArray. + newSize to: oldSize + 1 by: -1 do: [ :each | + freeSlotIndexes addFirst: each ]. + Smalltalk maxExternalSemaphores ifNotNil: [ :maxExternalSemaphores | + "Make sure that those new external semaphores can be signaled by the VM. This is not entirely safe, but not incrementing at all is worse." + newSize > maxExternalSemaphores ifTrue: [ + Smalltalk maxExternalSemaphores: newSize ] ] + + ! Item was added: + ----- Method: ExternalObjectTable>>externalObjects (in category 'accessing') ----- + externalObjects + "Return a copy of the externalObjectsArray." + + ^semaphore critical: [ + self synchronizeExternalObjectsArrayAndForceUpdate: false. + externalObjectsArray copy ]! Item was added: + ----- Method: ExternalObjectTable>>externalObjectsArray: (in category 'private') ----- + externalObjectsArray: anArray + "Update the index mapping using anArray as the new externalObjectsArray." + + externalObjectsArray := anArray. + freeSlotIndexes reset. + indexesByObjects removeAll. + 1 to: externalObjectsArray size do: [ :index | + (anArray at: index) + ifNil: [ freeSlotIndexes addFirst: index ] + ifNotNil: [ :object | indexesByObjects at: object put: index ] ]! Item was added: + ----- Method: ExternalObjectTable>>initialize (in category 'initialize-release') ----- + initialize + + semaphore := Semaphore forMutualExclusion. + self initializeCaches! Item was added: + ----- Method: ExternalObjectTable>>initializeCaches (in category 'private') ----- + initializeCaches + + freeSlotIndexes := OrderedCollection new. + indexesByObjects := IdentityDictionary new! Item was added: + ----- Method: ExternalObjectTable>>newExternalSemaphore (in category 'accessing') ----- + newExternalSemaphore + "Create and register a new Semaphore, and return an array containing itself and its index." + + | newSemaphore | + ^{ + newSemaphore := Semaphore new. + semaphore critical: [ + self + synchronizeExternalObjectsArrayAndForceUpdate: false; + safelyRegisterNewExternalObject: newSemaphore ] }! Item was added: + ----- Method: ExternalObjectTable>>newExternalSemaphoreDo: (in category 'accessing') ----- + newExternalSemaphoreDo: aBlock + "Create and register a new Semaphore, then evaluate aBlock with it and its index." + + | newSemaphore | + ^aBlock + value: (newSemaphore := Semaphore new) + value: (semaphore critical: [ + self + synchronizeExternalObjectsArrayAndForceUpdate: false; + safelyRegisterNewExternalObject: newSemaphore ])! Item was added: + ----- Method: ExternalObjectTable>>newExternalSemaphores: (in category 'accessing') ----- + newExternalSemaphores: count + "Create and register multiple Semaphores, and return an array containing the semaphores and their indexes in separate arrays." + + | semaphores indexes | + semaphores := Array new: count. + 1 to: count do: [ :index | semaphores at: index put: Semaphore new ]. + indexes := Array new: count. + semaphore critical: [ + self synchronizeExternalObjectsArrayAndForceUpdate: false. + 1 to: count do: [ :index | + indexes at: index put: ( + self safelyRegisterNewExternalObject: (semaphores at: index)) ] ]. + ^{ semaphores. indexes }! Item was added: + ----- Method: ExternalObjectTable>>registerExternalObject: (in category 'accessing') ----- + registerExternalObject: anObject + "Register the given object in the external objects array and return its index. If it is already there, just return its index." + + anObject ifNil: [ ^nil ]. + ^semaphore critical: [ + self + synchronizeExternalObjectsArrayAndForceUpdate: false; + safelyRegisterExternalObject: anObject ]! Item was added: + ----- Method: ExternalObjectTable>>safelyRegisterExternalObject: (in category 'private') ----- + safelyRegisterExternalObject: anObject + + | index | + (index := indexesByObjects at: anObject ifAbsent: nil) ifNotNil: [ + (externalObjectsArray at: index) == anObject ifTrue: [ ^index ]. + "indexesByObjects is out of sync. Try again." + ^self + synchronizeExternalObjectsArrayAndForceUpdate: true; + safelyRegisterExternalObject: anObject ]. + ^self safelyRegisterNewExternalObject: anObject! Item was added: + ----- Method: ExternalObjectTable>>safelyRegisterNewExternalObject: (in category 'private') ----- + safelyRegisterNewExternalObject: anObject + + | index | + self ensureFreeSlot. + index := freeSlotIndexes removeLast. + (externalObjectsArray at: index) ifNotNil: [ + "Free slot is not empty. Try again." + ^self + synchronizeExternalObjectsArrayAndForceUpdate: true; + safelyRegisterNewExternalObject: anObject ]. + externalObjectsArray at: index put: anObject. + indexesByObjects at: anObject put: index. + ^index! Item was added: + ----- Method: ExternalObjectTable>>safelyUnregisterExternalObject: (in category 'private') ----- + safelyUnregisterExternalObject: anObject + + (indexesByObjects removeKey: anObject ifAbsent: nil) + ifNotNil: [ :index | + (externalObjectsArray at: index) == anObject ifFalse: [ + "We're not in sync. Try again." + ^self + synchronizeExternalObjectsArrayAndForceUpdate: true; + safelyUnregisterExternalObject: anObject ]. + externalObjectsArray at: index put: nil. + freeSlotIndexes add: index ] + ifNil: [ + "Check if we're just out of sync." + (externalObjectsArray instVarsInclude: anObject) ifFalse: [ ^self ]. + "We're not in sync. Try again." + ^self + synchronizeExternalObjectsArrayAndForceUpdate: true; + safelyUnregisterExternalObject: anObject ]! Item was added: + ----- Method: ExternalObjectTable>>synchronizeExternalObjectsArrayAndForceUpdate: (in category 'private') ----- + synchronizeExternalObjectsArrayAndForceUpdate: forceUpdate + + | actualExternalObjectsArray | + actualExternalObjectsArray := Smalltalk specialObjectsArray at: 39. + (actualExternalObjectsArray == externalObjectsArray and: [ forceUpdate not ]) + ifTrue: [ ^self ]. + self externalObjectsArray: actualExternalObjectsArray! Item was added: + ----- Method: ExternalObjectTable>>unregisterExternalObject: (in category 'accessing') ----- + unregisterExternalObject: anObject + "Unregister the given object from the external objects array. Do nothing if it isn't registered." + + anObject ifNil: [ ^self ]. + semaphore critical: [ + self + synchronizeExternalObjectsArrayAndForceUpdate: false; + safelyUnregisterExternalObject: anObject ]! Item was added: + ----- Method: ExternalObjectTable>>unregisterExternalObjects: (in category 'accessing') ----- + unregisterExternalObjects: aCollection + "Unregister the given objects from the external objects array. Do nothing if they aren't registered." + + semaphore critical: [ + self synchronizeExternalObjectsArrayAndForceUpdate: false. + aCollection do: [ :each | + each ifNotNil: [ + self safelyUnregisterExternalObject: each ] ] ]! Item was removed: - Object subclass: #ExternalSemaphoreTable - instanceVariableNames: '' - classVariableNames: 'ProtectTable' - poolDictionaries: '' - category: 'System-Support'! - - !ExternalSemaphoreTable commentStamp: '<historical>' prior: 0! - By John M McIntosh johnmci(a)smalltalkconsulting.com - This class was written to mange the external semaphore table. When I was writing a Socket test server I discovered various race conditions on the access to the externalSemaphore table. This new class uses class side methods to restrict access using a mutex semaphore. It seemed cleaner to deligate the reponsibility here versus adding more code and another class variable to SystemDictionary - - Note that in Smalltalk recreateSpecialObjectsArray we still directly play with the table.! Item was removed: - ----- Method: ExternalSemaphoreTable class>>clearExternalObjects (in category 'accessing') ----- - clearExternalObjects - "Clear the array of objects that have been registered for use in non-Smalltalk code." - - ProtectTable critical: [Smalltalk specialObjectsArray at: 39 put: Array new]. - ! Item was removed: - ----- Method: ExternalSemaphoreTable class>>externalObjects (in category 'accessing') ----- - externalObjects - ^ProtectTable critical: [Smalltalk specialObjectsArray at: 39].! Item was removed: - ----- Method: ExternalSemaphoreTable class>>initialize (in category 'initialize') ----- - initialize - ProtectTable := Semaphore forMutualExclusion! Item was removed: - ----- Method: ExternalSemaphoreTable class>>registerExternalObject: (in category 'accessing') ----- - registerExternalObject: anObject - ^ ProtectTable critical: [self safelyRegisterExternalObject: anObject] - ! Item was removed: - ----- Method: ExternalSemaphoreTable class>>safelyRegisterExternalObject: (in category 'accessing') ----- - safelyRegisterExternalObject: anObject - "Register the given object in the external objects array and return its index. If it is already there, just return its index." - - | objects firstEmptyIndex obj sz newObjects | - objects := Smalltalk specialObjectsArray at: 39. - - "find the first empty slot" - firstEmptyIndex := 0. - 1 to: objects size do: [:i | - obj := objects at: i. - obj == anObject ifTrue: [^ i]. "object already there, just return its index" - (obj == nil and: [firstEmptyIndex = 0]) ifTrue: [firstEmptyIndex := i]]. - - "if no empty slots, expand the array" - firstEmptyIndex = 0 ifTrue: [ - sz := objects size. - newObjects := objects species new: sz + 20. "grow linearly" - newObjects replaceFrom: 1 to: sz with: objects startingAt: 1. - firstEmptyIndex := sz + 1. - Smalltalk specialObjectsArray at: 39 put: newObjects. - objects := newObjects]. - - objects at: firstEmptyIndex put: anObject. - ^ firstEmptyIndex - ! Item was removed: - ----- Method: ExternalSemaphoreTable class>>safelyUnregisterExternalObject: (in category 'accessing') ----- - safelyUnregisterExternalObject: anObject - "Unregister the given object in the external objects array. Do nothing if it isn't registered. - JMM change to return if we clear the element, since it should only appear once in the array" - - | objects | - anObject ifNil: [^ self]. - objects := Smalltalk specialObjectsArray at: 39. - 1 to: objects size do: [:i | - (objects at: i) == anObject ifTrue: - [objects at: i put: nil. - ^self]]. - ! Item was removed: - ----- Method: ExternalSemaphoreTable class>>unregisterExternalObject: (in category 'accessing') ----- - unregisterExternalObject: anObject - ProtectTable critical: [self safelyUnregisterExternalObject: anObject] - ! Item was changed: + ----- Method: SmalltalkImage>>clearExternalObjects (in category 'external objects') ----- - ----- Method: SmalltalkImage>>clearExternalObjects (in category 'special objects') ----- clearExternalObjects "Clear the array of objects that have been registered for use in non-Smalltalk code." "Smalltalk clearExternalObjects" + ExternalObjectTable current clearExternalObjects - ExternalSemaphoreTable clearExternalObjects ! Item was changed: + ----- Method: SmalltalkImage>>externalObjects (in category 'external objects') ----- - ----- Method: SmalltalkImage>>externalObjects (in category 'special objects') ----- externalObjects "Return an array of objects that have been registered for use in non-Smalltalk code. Smalltalk objects should be referrenced by external code only via indirection through this array, thus allowing the objects to move during compaction. This array can be cleared when the VM re-starts, since variables in external code do not survive snapshots. Note that external code should not attempt to access a Smalltalk object, even via this mechanism, while garbage collection is in progress." + "Note that this is just a copy of the array used by the VM." "Smalltalk externalObjects" + ^ExternalObjectTable current externalObjects - ^ ExternalSemaphoreTable externalObjects ! Item was added: + ----- Method: SmalltalkImage>>newExternalSemaphore (in category 'external objects') ----- + newExternalSemaphore + "Create and register a new Semaphore, and return an array containing itself and its index." + + ^ExternalObjectTable current newExternalSemaphore! Item was added: + ----- Method: SmalltalkImage>>newExternalSemaphoreDo: (in category 'external objects') ----- + newExternalSemaphoreDo: aBlock + "Create and register a new Semaphore, then evaluate aBlock with it and its index." + + ^ExternalObjectTable current newExternalSemaphoreDo: aBlock! Item was added: + ----- Method: SmalltalkImage>>newExternalSemaphores: (in category 'external objects') ----- + newExternalSemaphores: count + "Create and register multiple Semaphores, and return an array containing the semaphores and their indexes in separate arrays." + + ^ExternalObjectTable current newExternalSemaphores: count! Item was changed: + ----- Method: SmalltalkImage>>registerExternalObject: (in category 'external objects') ----- - ----- Method: SmalltalkImage>>registerExternalObject: (in category 'special objects') ----- registerExternalObject: anObject "Register the given object in the external objects array and return its index. If it is already there, just return its index." + ^ExternalObjectTable current registerExternalObject: anObject! - ^ExternalSemaphoreTable registerExternalObject: anObject! Item was changed: + ----- Method: SmalltalkImage>>unregisterExternalObject: (in category 'external objects') ----- - ----- Method: SmalltalkImage>>unregisterExternalObject: (in category 'special objects') ----- unregisterExternalObject: anObject "Unregister the given object in the external objects array. Do nothing if it isn't registered." + ExternalObjectTable current unregisterExternalObject: anObject! - ExternalSemaphoreTable unregisterExternalObject: anObject! Item was added: + ----- Method: SmalltalkImage>>unregisterExternalObjects: (in category 'external objects') ----- + unregisterExternalObjects: aCollection + "Unregister the given objects from the external objects array. Do nothing if they aren't registered." + + ExternalObjectTable current unregisterExternalObjects: aCollection!

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Color>>quickHighLight: problems with transparent images
by tim Rowledge 27 Oct '14

27 Oct '14

The Color>>quickHighLight: method is ancient and appears to be wrong when using ‘modern’ pixel values where 0 is transparent and 16r1 is black. The use case is getting a decently visible colour for a cursor when painted onto an arbitrarily coloured background image. Strictly speaking a bitwise reverse isn’t a perceptually reliable algorithm but it is at least quick and usually tolerable. Consider the following code - |bitBlt bufferForm| bufferForm := Form extent: 100@20 depth: 32. bufferForm fillWhite. bitBlt := (BitBlt toForm: bufferForm) clipRect: bufferForm boundingBox; fillColor: (Color quickHighLight: bufferForm depth); combinationRule: Form reverse. bitBlt destRect: (0@0 extent: (bufferForm width /2) @bufferForm height); copyBits. bufferForm displayOn: Display at: 0@0 rule: Form paint What one wants to see is a patch in the top left of the Display with a 50x20 black area and a 50x20 white area. You get 50x20 transparent (ie nothing visible) and 50x20 white. If we change the code to |bitBlt bufferForm| bufferForm := Form extent: 100@20 depth: 32. bufferForm fillWhite. bitBlt := (BitBlt toForm: bufferForm) clipRect: bufferForm boundingBox; fillColor: (Bitmap with: 16rFFFFFFFE); combinationRule: Form reverse. bitBlt destRect: (0@0 extent: (bufferForm width /2) @bufferForm height); copyBits. bufferForm displayOn: Display at: 0@0 rule: Form paint … then we see what we wanted. I’m not completely convinced that changing the Color>>initializeHighLights method to - initializeHighLights "Create a set of Bitmaps for quickly reversing areas of the screen without converting colors. " "Color initializeHighLights" | t | t := Array new: 32. t at: 1 put: (Bitmap with: 16rFFFFFFFF). t at: 2 put: (Bitmap with: 16rFFFFFFFF). t at: 4 put: (Bitmap with: 16r55555555). t at: 8 put: (Bitmap with: 16r7070707). t at: 16 put: (Bitmap with: 16rFFFFFFFF). t at: 32 put: (Bitmap with: 16rFFFFFFFE). HighLightBitmaps := t. … is completely correct, but it might be. Does the 16bpp case need changing? Is there a bitblt rule I’m unaware of that does things better? tim -- tim Rowledge; tim(a)rowledge.org; http://www.rowledge.org/tim Useful Latin Phrases:- Fac ut vivas. = Get a life.

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The Trunk: Collections-ul.586.mcz
by commits＠source.squeak.org 27 Oct '14

27 Oct '14

Levente Uzonyi uploaded a new version of Collections to project The Trunk: http://source.squeak.org/trunk/Collections-ul.586.mcz ==================== Summary ==================== Name: Collections-ul.586 Author: ul Time: 27 October 2014, 12:52:51.886 am UUID: 4c460675-3065-4b48-aa30-52ad67e15076 Ancestors: Collections-cmm.585 Symbol table changes: - ensure that enumerations stay consistent - avoid read-write and write-write race conditions - added a safe #condenseNewSymbols method, which is a replacement for former unsafe methods (#shutDown: and #compactSymbolTable). It's also automatically triggered whenever there are more than 1000 NewSymbols. - deprecated #compactSymbolTable - updated some comments Note that interning many symbols is a bit slower, but thread safety is more important. =============== Diff against Collections-cmm.585 =============== Item was changed: ----- Method: Symbol class>>allSymbolTablesDo: (in category 'class initialization') ----- allSymbolTablesDo: aBlock + + | originalNewSymbols originalSymbolTable | + originalNewSymbols := NewSymbols. + originalSymbolTable := SymbolTable. + originalNewSymbols do: aBlock. + originalSymbolTable do: aBlock.! - - NewSymbols do: aBlock. - SymbolTable do: aBlock.! Item was changed: ----- Method: Symbol class>>allSymbolTablesDo:after: (in category 'class initialization') ----- allSymbolTablesDo: aBlock after: aSymbol + | originalNewSymbols originalSymbolTable | + originalNewSymbols := NewSymbols. + originalSymbolTable := SymbolTable. + (originalNewSymbols includes: aSymbol) - (NewSymbols includes: aSymbol) ifTrue: [ + originalNewSymbols do: aBlock after: aSymbol. + originalSymbolTable do: aBlock after: aSymbol ] - NewSymbols do: aBlock after: aSymbol. - SymbolTable do: aBlock after: aSymbol ] ifFalse: [ + originalSymbolTable do: aBlock after: aSymbol. + originalNewSymbols do: aBlock after: aSymbol ] - SymbolTable do: aBlock after: aSymbol. - NewSymbols do: aBlock after: aSymbol ] ! Item was changed: ----- Method: Symbol class>>allSymbols (in category 'access') ----- allSymbols "Answer all interned symbols" + | originalNewSymbols originalSymbolTable | + originalNewSymbols := NewSymbols. + originalSymbolTable := SymbolTable. ^Array + new: originalNewSymbols slowSize + originalSymbolTable slowSize - new: NewSymbols slowSize + SymbolTable slowSize streamContents:[ :stream | stream + nextPutAll: originalNewSymbols; + nextPutAll: originalSymbolTable ] - nextPutAll: NewSymbols; - nextPutAll: SymbolTable ] ! Item was changed: ----- Method: Symbol class>>cleanUp (in category 'class initialization') ----- cleanUp "Flush caches" + self condenseNewSymbols! - self compactSymbolTable.! Item was changed: ----- Method: Symbol class>>compactSymbolTable (in category 'class initialization') ----- compactSymbolTable "Reduce the size of the symbol table so that it holds all existing symbols with 25% free space." + self deprecated: 'Use #condenseNewSymbols instead'. + self condenseNewSymbols! - | oldSize | - Smalltalk garbageCollect. - oldSize := SymbolTable capacity. - SymbolTable compact. - ^(oldSize - SymbolTable capacity) printString, ' slot(s) reclaimed'! Item was added: + ----- Method: Symbol class>>condenseNewSymbols (in category 'private') ----- + condenseNewSymbols + "Move all symbols from NewSymbols to SymbolTable, and compact SymbolTable." + + | originalNewSymbols originalSymbolTable newNewSymbols newSymbolTable | + originalNewSymbols := NewSymbols. + originalSymbolTable := SymbolTable. + newNewSymbols := WeakSet new. + newSymbolTable := originalSymbolTable copy + addAll: originalNewSymbols; + compact; + yourself. + originalNewSymbols == NewSymbols ifFalse: [ + "Some other process has modified the symbols. Try again." + ^self condenseNewSymbols ]. + NewSymbols := newNewSymbols. + SymbolTable := newSymbolTable! Item was changed: ----- Method: Symbol class>>intern: (in category 'instance creation') ----- intern: aStringOrSymbol + | originalNewSymbols | + originalNewSymbols := NewSymbols. ^(self lookup: aStringOrSymbol) ifNil:[ + | aClass aSymbol newNewSymbols | - | aClass aSymbol | aStringOrSymbol isSymbol ifTrue:[ aSymbol := aStringOrSymbol. ] ifFalse:[ aClass := aStringOrSymbol isOctetString ifTrue:[ByteSymbol] ifFalse:[WideSymbol]. aSymbol := aClass new: aStringOrSymbol size. aSymbol string: aStringOrSymbol. ]. + newNewSymbols := originalNewSymbols copyWith: aSymbol. + originalNewSymbols == NewSymbols + ifTrue: [ + NewSymbols := newNewSymbols. + newNewSymbols size > 1000 ifTrue: [ self condenseNewSymbols ]. + aSymbol ] + ifFalse: [ + "Some other process has modified the symbols. Try again." + self intern: aStringOrSymbol ] ]! - NewSymbols add: aSymbol. - aSymbol].! Item was changed: ----- Method: Symbol class>>lookup: (in category 'instance creation') ----- lookup: aStringOrSymbol + | originalNewSymbols originalSymbolTable | + originalNewSymbols := NewSymbols. + originalSymbolTable := SymbolTable. + ^(originalNewSymbols like: aStringOrSymbol) ifNil: [ + originalSymbolTable like: aStringOrSymbol ]! - ^(SymbolTable like: aStringOrSymbol) ifNil: [ - NewSymbols like: aStringOrSymbol - ]! Item was changed: ----- Method: Symbol class>>rehash (in category 'private') ----- + rehash + "Rebuild the hash table, reclaiming unreferenced Symbols. This method will intern all symbols. You're probably looking for #condenseNewSymbols instead." - rehash "Symbol rehash" - "Rebuild the hash table, reclaiming unreferenced Symbols." + | originalNewSymbols originalSymbolTable newNewSymbols newSymbolTable | + originalNewSymbols := NewSymbols. + originalSymbolTable := SymbolTable. + newNewSymbols := WeakSet new. + newSymbolTable := WeakSet withAll: self allSubInstances. + originalNewSymbols == NewSymbols ifFalse: [ + "Some other process has modified the symbols. Try again." + ^self rehash ]. + NewSymbols := newNewSymbols. + SymbolTable := newSymbolTable! - SymbolTable := WeakSet withAll: self allSubInstances. - NewSymbols := WeakSet new.! Item was changed: ----- Method: Symbol class>>shutDown: (in category 'private') ----- shutDown: aboutToQuit + self condenseNewSymbols! - SymbolTable addAll: NewSymbols. - NewSymbols := WeakSet new.!

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Re: [Pharo-dev] Should literals be immutable ?
by Eliot Miranda 27 Oct '14

27 Oct '14

On Mon, Oct 27, 2014 at 9:19 AM, Levente Uzonyi <leves(a)elte.hu> wrote: > On Mon, 27 Oct 2014, Clément Bera wrote: > > Hey guys, >> I was discussing about methods like that with Marcus: >> >> MyClass>>foo >> #(false) first >> ifFalse: [ >> 'first call since compilation' logCr. >> #(false) at: 1 put: true ] >> ifTrue: [ 'other calls' logCr ] >> >> DoIt: >> 4 timesRepeat: [MyClass new foo ] >> >> Transcript: >> 'first call since compilation' >> 'other calls' >> 'other calls' >> 'other calls' >> >> In the sista image/VM, we are most probably going with Eliot to implement >> a slow path when you edit the literal of a method (deoptimizing the method) >> so we can consider that the literals are immutable in the >> generic case (and if it's not true, execution falls back to a slow path). >> >> But I was thinking, does it worth it to implement the slow path ? >> Couldn't we just put literals as immutable all the time ? >> The methods as the one shown before would not work any more. But does >> someone use it ? >> > > This method was used in Seaside (or some Seaside extension) to cache the > contents of files in methods. > > By the way, how would you ensure immutability? > See my message earlier in the thread. Via a per-object isImmutable bit. > I mean, how would you prevent something like this? > > MyClass >> foo > > ^#('placeHolder') > > And then > > (((MyClass >> #foo) literalAt: 1) at: 1) becomeForward: Object new > > > Levente > > P.S.: why isn't this on the vm-dev list? > > >> ... >> >> >> -- best, Eliot

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Re: [Pharo-dev] Should literals be immutable ?
by Eliot Miranda 27 Oct '14

27 Oct '14

Hi Clément, IMO literals should be immutable all the time, and IMO the best way is via a per-object isImmutable bit. We implemented this for VW in 7.0 and it was a positive experience. I've implemented the "create an immutable subclass for each literal class" and it has lots of problems (thing printString or storeString having to produce something like 'an immutable string' asMutableString for a normal string). The per-object bit has other uses too. Object databases such as GemStone can use it to make write-through scheme efficient. The only problem we had was dealing with broken user code that was depending on mutable literals. This is of course a bug, but folks thought we shouldn't just break user code so Alan Knight provided a system setting that write a warning to the transcript and updated the literal instead if raising an error. That's easy to do, if IMO dubious. Fixing the code is as easy as sending copy to the literal in question, the copy being mutable. Now I implemented the per-object bit for the Newspeak interpreter WM so you'll find lots of the necessary work is there waiting to be ported to the Stack and Cog VMs. I've not had the time to implement the JIT support to catch inst var and at:put: writes to immutables. But it shouldn't be too much work. Volunteers? Eliot (phone) On Oct 27, 2014, at 8:22 AM, Clément Bera <bera.clement(a)gmail.com> wrote: > Hey guys, > > I was discussing about methods like that with Marcus: > > MyClass>>foo > #(false) first > ifFalse: [ > 'first call since compilation' logCr. > #(false) at: 1 put: true ] > ifTrue: [ 'other calls' logCr ] > > DoIt: > 4 timesRepeat: [MyClass new foo ] > > Transcript: > 'first call since compilation' > 'other calls' > 'other calls' > 'other calls' > > In the sista image/VM, we are most probably going with Eliot to implement a slow path when you edit the literal of a method (deoptimizing the method) so we can consider that the literals are immutable in the generic case (and if it's not true, execution falls back to a slow path). > > But I was thinking, does it worth it to implement the slow path ? > Couldn't we just put literals as immutable all the time ? > The methods as the one shown before would not work any more. But does someone use it ? > > ... >

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