The Trunk: Kernel-ul.362.mcz

Levente Uzonyi uploaded a new version of Kernel to project The Trunk:
http://source.squeak.org/trunk/Kernel-ul.362.mcz

==================== Summary ====================

Name: Kernel-ul.362
Author: ul
Time: 31 December 2009, 7:04:23 am
UUID: 96615f68-2456-7745-9ecb-335973913252
Ancestors: Kernel-ul.361

- speed up method trailer creation
- speed up source fetching from source files

=============== Diff against Kernel-ar.360 ===============

Item was added:
+ ----- Method: CompiledMethod>>getSourceFromFileAt: (in category 'source code management') -----
+ getSourceFromFileAt: sourcePointer
+
+ | position index |
+ position := SourceFiles filePositionFromSourcePointer: sourcePointer.
+ position = 0 ifTrue: [ ^nil ].
+ index := SourceFiles fileIndexFromSourcePointer: sourcePointer.
+ ^(RemoteString newFileNumber: index position: position)
+ text!

Item was added:
+ ----- Method: CompiledMethodTrailer class>>trailerKindDecoders (in category 'generated') -----
+ trailerKindDecoders
+
+ ^#(#decodeNoTrailer #decodeClearedTrailer #decodeTempsNamesQCompress #decodeTempsNamesZip #decodeSourceBySelector #decodeSourceByStringIdentifier #decodeEmbeddedSourceQCompress #decodeEmbeddedSourceZip #decodeVarLengthSourcePointer #decodeExtendedKind #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeUndefined #decodeSourcePointer)!

Item was changed:
  ----- Method: CompiledMethod>>getSourceFor:in: (in category 'source code management') -----
  getSourceFor: selector in: class
  "Retrieve or reconstruct the source code for this method."
  | trailer source |
  trailer := self trailer.
 
  trailer tempNames ifNotNil: [:namesString |
  "Magic sources -- decompile with temp names"
  ^ ((class decompilerClass new withTempNames: namesString)
  decompile: selector in: class method: self)
  decompileString].
 
  trailer sourceCode ifNotNil: [:code | ^ code ].
 
  trailer hasSourcePointer ifFalse: [
  "No source pointer -- decompile without temp names"
  ^ (class decompilerClass new decompile: selector in: class method: self)
  decompileString].
 
  "Situation normal;  read the sourceCode from the file"
+ source := [self getSourceFromFileAt: trailer sourcePointer]
- source := [self getSourceFromFile]
  on: Error
  "An error can happen here if, for example, the changes file has been truncated by an aborted download.  The present solution is to ignore the error and fall back on the decompiler.  A more thorough solution should probably trigger a systematic invalidation of all source pointers past the end of the changes file.  Consider that, as time goes on, the changes file will eventually grow large enough to cover the lost code, and then instead of falling into this error case, random source code will get returned."
  do: [ :ex | ex return: nil].
 
  ^source ifNil: [
  "Something really wrong -- decompile blind (no temps)"
  (class decompilerClass new decompile: selector in: class method: self)
  decompileString]!

Item was changed:
  ----- Method: CompiledMethod>>getSourceFromFile (in category 'source code management') -----
  getSourceFromFile
+
+ ^self getSourceFromFileAt: self sourcePointer!
- "Read the source code from file, determining source file index and
- file position from the last 3 bytes of this method."
- | position |
- (position := self filePosition) = 0 ifTrue: [^ nil].
- ^ (RemoteString newFileNumber: self fileIndex position: position)
- text!

Item was changed:
  ----- Method: CompiledMethodTrailer>>method: (in category 'initialize-release') -----
  method: aMethod
 
+ | flagByte index |
- | flagByte |
-
  data := size := nil.
  method := aMethod.
+ flagByte := method at: method size.
- flagByte := method at: (method size).
 
  "trailer kind encoded in 6 high bits of last byte"
+ index := flagByte >> 2 + 1.
+ kind := self class trailerKinds at: index.
- kind := self class trailerKinds at: 1+(flagByte>>2).
 
  "decode the trailer bytes"
+ self perform: (self class trailerKindDecoders at: index).
- self perform: ('decode' , kind) asSymbol.
 
  "after decoding the trailer, size must be set"
+ self assert: size notNil
- self assert: (size notNil).
 
  !

Item was changed:
  ----- Method: CompiledMethodTrailer class>>trailerKinds (in category 'as yet unclassified') -----
  trailerKinds
+ " see class comment for description. If you change this method, evaluate this:
+ self generateTrailerKindDecoders"
+
+ ^#(
- " see class comment for description"
- ^#(
  "000000" #NoTrailer
  "000001" #ClearedTrailer
  "000010" #TempsNamesQCompress
  "000011" #TempsNamesZip
  "000100" #SourceBySelector
  "000101" #SourceByStringIdentifier
  "000110" #EmbeddedSourceQCompress
  "000111" #EmbeddedSourceZip
  "001000" #VarLengthSourcePointer
  "001001" #ExtendedKind
  "001010" #Undefined
  "001011" #Undefined
  "001100" #Undefined
  "001101" #Undefined
  "001110" #Undefined
  "001111" #Undefined
  "010000" #Undefined
  "010001" #Undefined
  "010010" #Undefined
  "010011" #Undefined
  "010100" #Undefined
  "010101" #Undefined
  "010110" #Undefined
  "010111" #Undefined
  "011000" #Undefined
  "011001" #Undefined
  "011010" #Undefined
  "011011" #Undefined
  "011100" #Undefined
  "011101" #Undefined
  "011110" #Undefined
  "011111" #Undefined
  "100000" #Undefined
  "100001" #Undefined
  "100010" #Undefined
  "100011" #Undefined
  "100100" #Undefined
  "100101" #Undefined
  "100110" #Undefined
  "100111" #Undefined
  "101000" #Undefined
  "101001" #Undefined
  "101010" #Undefined
  "101011" #Undefined
  "101100" #Undefined
  "101101" #Undefined
  "101110" #Undefined
  "101111" #Undefined
  "110000" #Undefined
  "110001" #Undefined
  "110010" #Undefined
  "110011" #Undefined
  "110100" #Undefined
  "110101" #Undefined
  "110110" #Undefined
  "110111" #Undefined
  "111000" #Undefined
  "111001" #Undefined
  "111010" #Undefined
  "111011" #Undefined
  "111100" #Undefined
  "111101" #Undefined
  "111110" #Undefined
  "111111" #SourcePointer
+ )!
- )!

Item was changed:
  Object subclass: #CompiledMethodTrailer
  instanceVariableNames: 'data encodedData kind size method'
  classVariableNames: ''
  poolDictionaries: ''
  category: 'Kernel-Methods'!
 
+ !CompiledMethodTrailer commentStamp: 'ul 12/31/2009 19:03' prior: 0!
- !CompiledMethodTrailer commentStamp: 'Igor.Stasenko 12/13/2009 12:53' prior: 0!
  I am responsible for encoding and decoding various kinds of compiled method trailer data.
  I should not expose any binary data outside of myself, so all tools which working with compiled methods
  should ask me to encode the meta-data, they want to be added to the compiled method trailer, as well as retrieve it.
 
  To add a new kind of trailer, you should give it a proper name and define it in the #trailerKinds method at my class side.
+ Then you need to implement a corresponding #encode<your name> and #decode<your name> methods at instance side. Then add any public accessor methods, which will use a newly introduced trailer kind for communicating with outer layer(s). And finally evaluate: self generateTrailerKindDecoders.
- Then you need to implement a corresponding #encode<your name> and #decode<your name> methods at instance side. Then add any public accessor methods, which will use a newly introduced trailer kind for communicating with outer layer(s).
 
  An encodeXXX methods should store result (byte array) into encodedData instance variable.
 
  A decodeXXX methods should read the data from compiled method instance, held by 'method' ivar,
  and always set 'size' ivar (denoting a total length of trailer in compiled method) and optionally 'data' ivar which should keep a decoded data, ready to be used by outer layer(s) using accessor method(s) you providing.
 
  The kind of compiled method trailer is determined by the last byte of compiled method.
 
  The byte format used is following:
  "2rkkkkkkdd"
 
  where 'k' bits stands for 'kind' , allowing totally 64 different kinds of method trailer
  and 'd' bits is data.
 
  Following is the list of currently defined trailer kinds:
 
  NoTrailer , k = 000000, dd unused
  method has no trailer, and total trailer size bytes is always 1
 
  ClearedTrailer, k = 000001,
  method has cleared trailer (it was set to something else, but then cleared)
  dd+1  determines the number of bytes for size field, and size is a total length of trailer bytes
  So a total length of trailer is: 1 + (dd + 1) + size
 
  TempsNamesQCompress, k = 000010
  the trailer contains a list of method temp names,  compressed using qCompress: method.
  dd+1  determines the number of bytes for size field, and size is a number of bytes of compressed buffer.
  So a total length of trailer is:  1 + (dd + 1) + size
 
  TempsNamesZip, k = 000011
  the trailer contains a list of method temp names,  compressed using GZIP compression method.
  dd+1  determines the number of bytes for size field, and size is a number of bytes of compressed buffer
  So a total length of trailer is: 1 + (dd + 1) + size
 
  SourceBySelector, k = 000100
  the trailer indicates , that method source is determined by a class + selector where it is installed to.
  Trailer size = 1.
 
  SourceByStringIdentifier, k = 000101
  the trailer indicates , that method source is determined by a class + some ByteString identifier.
  dd+1  determines the number of bytes for size of ByteString identifier, and size is number of bytes of string.
  A total length of trailer is:  1 + (dd + 1) + size
 
  EmbeddedSourceQCompress, k = 000110
  the trailer contains an utf-8 encoded method source code, compressed using qCompress method
  dd+1  determines the number of bytes for size field, and size is a number of bytes of compressed source code
  A total length of trailer is:  1 + (dd + 1) + size
 
  EmbeddedSourceZip, k = 000111
  the trailer contains an utf-8 encoded method source code, comressed using GZIP
  dd+1  determines the number of bytes for size field, and size is a number of bytes of compressed buffer
  A total length of trailer is:  1 + (dd + 1) + size
 
  VarLengthSourcePointer, k = 001000
  the trailer is variable-length encoded source pointer.
  dd bits is unused.
 
  ExtendedKind, k = 001001
  the next byte of trailer (one that prepends the last byte of compiled method)
  denotes an extended kind of trailer, allowing to use additional 256 kinds of encoding method's trailer in future.
 
  SourcePointer, k = 111111
  the trailer is encoded source pointer. Total trailer size is 4-bytes
  (this kind of encoding is backwards compatible with most of existing compiled methods)
 
  !

Item was added:
+ ----- Method: CompiledMethodTrailer class>>generateTrailerKindDecoders (in category 'as yet unclassified') -----
+ generateTrailerKindDecoders
+
+ self class
+ compile: (String streamContents: [ :stream |
+ stream
+ nextPutAll: 'trailerKindDecoders'; cr;
+ cr;
+ tab; nextPut: $^; print: (
+ self trailerKinds collect: [ :each |
+ ('decode', each) asSymbol ]) ])
+ classified: 'generated'
+ !