Hi Levente,
On Tue, Feb 28, 2017 at 10:44 AM, Levente Uzonyi leves@caesar.elte.hu wrote:
In case someone would like to defend the performance of #~~ and #notNil, here's a little benchmark I just wrote:
| base ifNilIfNotNil notIdentical notEqual notNil | Smalltalk garbageCollect. base := (1 to: 5) collect: [ :run | [ 1 to: 100000000 do: [ :i | ] ] timeToRun ].
ifNilIfNotNil := (1 to: 5) collect: [ :run | [ 1 to: 100000000 do: [ :i | i ifNil: [ false ] ifNotNil: [ true ] ] ] timeToRun ].
notIdentical := (1 to: 5) collect: [ :run | [ 1 to: 100000000 do: [ :i | i ~~ nil ] ] timeToRun ].
notEqual := (1 to: 5) collect: [ :run | [ 1 to: 100000000 do: [ :i | i ~= nil ] ] timeToRun ].
notNil := (1 to: 5) collect: [ :run | [ 1 to: 100000000 do: [ :i | i notNil ] ] timeToRun ].
{ #ifNilIfNotNil -> ifNilIfNotNil. #notIdentical -> notIdentical. #notEqual -> notEqual. #notNil -> notNil } replace: [ :each | each key -> (each value average - base average) asFloat ]; sort: #value ascending
"{#ifNilIfNotNil->73.6 . #notNil->336.8 . #notIdentical->511.6 . #notEqual->3354.0}"
So it's 4.5x faster than #notNil and 7x faster than #~~ on 64-bit Spur on Linux. Once we have jitted #~~, I'll change the code again.
IIRC, all one needs to get jitted #~~ is to store #~~ in place of blockCopy: in the specialSelectors array and recompile all senders of #~~. You may need to collect all senders of #~~ before you make the swap since putting it in the specialSelectors array may confuse allReferencesTo: et al.
Levente
On Tue, 28 Feb 2017, commits@source.squeak.org wrote:
Levente Uzonyi uploaded a new version of Collections to project The Trunk:
http://source.squeak.org/trunk/Collections-ul.739.mcz
==================== Summary ====================
Name: Collections-ul.739 Author: ul Time: 28 February 2017, 7:34:55.711173 pm UUID: 66c6ecf2-71bf-4e7d-80e6-5ace72fa19ba Ancestors: Collections-ul.738
- use micro optimization for #~~ and #notNil in common collection methods
- reuse one of the OrderedCollections in RunArray >> #scanFrom:
- two other minor tweaks in KeyedSet
- removed accidentally commited Set >> #includes2:
=============== Diff against Collections-ul.738 ===============
Item was changed: ----- Method: Dictionary>>includesKey: (in category 'testing') ----- includesKey: key "Answer whether the receiver has a key equal to the argument, key."
(array at: (self scanFor: key)) ifNil: [ ^false ] ifNotNil: [^true ]!
^(array at: (self scanFor: key)) notNil!Item was changed: ----- Method: KeyedSet>>includesKey: (in category 'testing') ----- includesKey: key
(array at: (self scanFor: key)) ifNil: [ ^false ] ifNotNil: [^true ]!
^ (array at: (self scanFor: key)) notNil!Item was changed: ----- Method: KeyedSet>>remove:ifAbsent: (in category 'removing') ----- remove: oldObject ifAbsent: aBlock
| index | index := self scanFor: (keyBlock value: oldObject).
(array at: index) ifNil: [ ^ aBlock value ].
(array at: index) == nil ifTrue: [ ^ aBlock value ]. array at: index put: nil. tally := tally - 1. self fixCollisionsFrom: index. ^ oldObject!Item was changed:
----- Method: KeyedSet>>removeKey:ifAbsent: (in category 'removing')
removeKey: key ifAbsent: aBlock
| index obj | index := self scanFor: key.
obj := (array at: index) ifNil: [ ^ aBlock value ].
(obj := array at: index) == nil ifTrue: [ ^ aBlock value ]. array at: index put: nil. tally := tally - 1. self fixCollisionsFrom: index. ^ obj enclosedSetElement!Item was changed: ----- Method: RunArray class>>scanFrom: (in category 'instance creation') ----- scanFrom: strm "Read the style section of a fileOut or sources file. nextChunk has already been done. We need to return a RunArray of TextAttributes of various kinds. These are written by the implementors of writeScanOn:" | runs values attrList char | (strm peekFor: $( ) ifFalse: [^ nil]. runs := OrderedCollection new. [strm skipSeparators. strm peekFor: $)] whileFalse: [runs add: (Number readFrom: strm)]. values := OrderedCollection new. "Value array" attrList := OrderedCollection new. "Attributes list" [(char := strm peek) == nil] whileFalse: [ (char isSeparator or: [ char = $!! ]) ifTrue: [ "n.b. Skip $!! to meet expectations of RunArrayTest>>testScanFromTrailer. The example string used in that test does not seem to match the implemention of the fileOut serialization, but the test may be right and the implementation wrong. In any case, relax the parsing here to meet the test expectations, and to be more consistent with the original version of this method that assumed any unexpected charater to be a separator. -dtl Jan 2014" strm next "space, cr do nothing"] ifFalse: [char == $, ifTrue: [strm next. values add: attrList asArray.
attrList reset ]
attrList :=OrderedCollection new] ifFalse: [attrList add: (TextAttribute newFrom: strm)] ] ]. values add: attrList asArray. ^ self runs: runs asArray values: (values copyFrom: 1 to: runs size) asArray " RunArray scanFrom: (ReadStream on: '(14 50 312)f1,f1b,f1LInteger +;i') "!
Item was removed:
- ----- Method: Set>>includes2: (in category 'testing') -----
- includes2: anObject - - ^((array at: (self scanFor: anObject)) ==
nil) not!
Item was changed: ----- Method: WeakIdentityDictionary>>includesKey: (in category 'testing') ----- includesKey: key "Answer whether the receiver has a key equal to the argument, key."
(array at: (self scanFor: key))ifNil: ["it just has been reclaimed"^false]ifNotNil: [ :element |element == vacuumifTrue: [ ^false ]ifFalse: [ ^true ] ]!
^(array at: (self scanFor: key))ifNil:["it just has been reclaimed"false]ifNotNil: [:element | element ~~ vacuum]!Item was changed: ----- Method: WeakSet>>includes: (in category 'testing') ----- includes: anObject
(array at: (self scanFor: anObject)) ifNil: [ ^false ]
ifNotNil: [ :object |object == flagifTrue: [ ^false ]ifFalse: [ ^true ] ]!
ifNotNil: [ :object | ^object ~~ flag ]!