Codegen refactoring [1/x]: Introduced a PPCCodeBlock
A PPCCodeBlock is an abstraction of a block of statements with temporaries. This will
allow for scoped temporary management in code generator - temporary variables could
be allocated for block only. (i.e., make them block-temporaries)
"{ Package: 'stx:goodies/petitparser/compiler' }"
"{ NameSpace: Smalltalk }"
Object subclass:#PPCCodeBlock
instanceVariableNames:'buffer indentation temporaries'
classVariableNames:''
poolDictionaries:''
category:'PetitCompiler-Compiler-Codegen'
!
!PPCCodeBlock class methodsFor:'instance creation'!
new
"return an initialized instance"
^ self basicNew initialize.
! !
!PPCCodeBlock methodsFor:'as yet unclassified'!
add: string
self nl.
((Smalltalk respondsTo:#isSmalltalkX) and:[ Smalltalk isSmalltalkX ]) ifTrue:[
indentation * 4 timesRepeat: [ buffer nextPut: Character space ].
] ifFalse:[
indentation timesRepeat: [ buffer nextPut: Character tab ].
].
self addOnLine: string.
"Modified: / 21-05-2015 / 15:42:18 / Jan Vrany <jan.vrany@fit.cvut.cz>"
!
addOnLine: string
buffer nextPutAll: string.
!
nl
^ buffer nextPut: Character cr
! !
!PPCCodeBlock methodsFor:'code generation'!
code: aStringOrBlock
aStringOrBlock isString ifTrue:[
buffer nextPutAll: aStringOrBlock
] ifFalse:[
aStringOrBlock value
].
"Created: / 01-06-2015 / 21:07:10 / Jan Vrany <jan.vrany@fit.cvut.cz>"
! !
!PPCCodeBlock methodsFor:'code generation - variables'!
allocateTemporaryVariableNamed:preferredName
"Allocate a new variable with (preferably) given name.
Returns a real variable name that should be used."
(temporaries includes:preferredName) ifFalse:[
temporaries add:preferredName.
^ preferredName
] ifTrue:[
| name |
name := preferredName , '_' , (temporaries size + 1) printString.
temporaries add:name.
^ name
].
"Created: / 23-04-2015 / 17:37:55 / Jan Vrany <jan.vrany@fit.cvut.cz>"
"Modified: / 01-06-2015 / 21:03:39 / Jan Vrany <jan.vrany@fit.cvut.cz>"
! !
!PPCCodeBlock methodsFor:'indentation'!
dedent
indentation := indentation - 1
!
indent
indentation := indentation + 1
!
indentationLevel
^ indentation
!
indentationLevel: value
indentation := value
! !
!PPCCodeBlock methodsFor:'initialization'!
initialize
"Invoked when a new instance is created."
"/ please change as required (and remove this comment)
buffer := String new writeStream.
indentation := 1.
temporaries := OrderedCollection new.
"/ super initialize. -- commented since inherited method does nothing
"Modified: / 01-06-2015 / 20:57:08 / Jan Vrany <jan.vrany@fit.cvut.cz>"
! !
!PPCCodeBlock methodsFor:'printing and storing'!
codeOn: aStream
"Dumps generated code on given stream"
temporaries notEmpty ifTrue:[
((Smalltalk respondsTo:#isSmalltalkX) and:[ Smalltalk isSmalltalkX ]) ifTrue:[
indentation * 4 timesRepeat: [ aStream nextPut: Character space ].
] ifFalse:[
indentation timesRepeat: [ buffer nextPut: Character tab ].
].
aStream nextPut: $|.
temporaries do:[:e | aStream space; nextPutAll: e ].
aStream space.
aStream nextPut: $|.
self nl.
"In Smalltalk/X, there should be a blank line after temporaries"
((Smalltalk respondsTo:#isSmalltalkX) and:[ Smalltalk isSmalltalkX ]) ifTrue:[
self nl.
].
].
aStream nextPutAll: buffer contents
"Created: / 01-06-2015 / 21:26:03 / Jan Vrany <jan.vrany@fit.cvut.cz>"
! !
!PPCCodeBlock class methodsFor:'documentation'!
version
^ 'Path: stx/goodies/petitparser/compiler/PPCCodeBlock.st, Version: 1.0, User: jv, Time: 2015-06-01T21:57:38.671+01'
!
version_HG
^ 'Path: stx/goodies/petitparser/compiler/PPCCodeBlock.st, Version: 1.0, User: jv, Time: 2015-06-01T21:57:38.671+01'
! !