"

 COPYRIGHT (c) 1989 by Claus Gittinger

	      All Rights Reserved

 This software is furnished under a license and may be used

 only in accordance with the terms of that license and with the

 inclusion of the above copyright notice.   This software may not

 be provided or otherwise made available to, or used by, any

 other person.  No title to or ownership of the software is

 hereby transferred.

"

"{ Package: 'stx:libcomp' }"

Object subclass:#ParseNode

	instanceVariableNames:'parent type comments parenthized startPosition endPosition

		attributes'

	classVariableNames:''

	poolDictionaries:''

	category:'System-Compiler-Support'

!

!ParseNode class methodsFor:'documentation'!

copyright

"

 COPYRIGHT (c) 1989 by Claus Gittinger

	      All Rights Reserved

 This software is furnished under a license and may be used

 only in accordance with the terms of that license and with the

 inclusion of the above copyright notice.   This software may not

 be provided or otherwise made available to, or used by, any

 other person.  No title to or ownership of the software is

 hereby transferred.

"

!

documentation

"

    node for parse-trees; abstract class

    This is a helper class for the compiler.

    [author:]

        Claus Gittinger

"

! !

!ParseNode class methodsFor:'instance creation'!

type:t

    ^ (self basicNew) type:t

! !

!ParseNode methodsFor:'accessing'!

enclosingBlock

    "Return closest enclosing block node or nil"

    | block |

    block := parent.

    [ block notNil and:[block isBlockNode not] ] whileTrue:[

        block := block parent.

    ].

    ^block.

    "Created: / 16-02-2012 / 22:46:12 / Jan Vrany <jan.vrany@fit.cvut.cz>"

!

endPosition

    ^ endPosition

!

endPosition:aCharacterPosition

    endPosition := aCharacterPosition

    "Modified: / 28-07-2011 / 10:03:53 / Jan Vrany <jan.vrany@fit.cvut.cz>"

!

line

    "Compatibility"

    ^self lineNumber

    "Created: / 09-07-2011 / 22:30:38 / Jan Vrany <jan.vrany@fit.cvut.cz>"

!

lineNumber

    ^nil

    "Created: / 09-07-2011 / 22:30:57 / Jan Vrany <jan.vrany@fit.cvut.cz>"

!

lineNumber:dummy

    "set linenumber - ignored here"

    ^ self

!

parent

    ^parent

    "Created: / 11-07-2011 / 17:36:43 / Jan Vrany <jan.vrany@fit.cvut.cz>"

!

parent: aParseNode

    parent := aParseNode

    "Created: / 11-07-2011 / 17:36:33 / Jan Vrany <jan.vrany@fit.cvut.cz>"

!

parenthesized

    ^ parenthized ? false

!

parenthesized:aBoolean

    parenthized := aBoolean

!

parenthized

    "obsolete - typo in message name - use parenthesized"

    ^ parenthized ? false

!

parenthized:aBoolean

    "obsolete - typo in message name - use parenthesized:"

    parenthized := aBoolean

!

selectorPartPositions:selectorPartPositions

    "/ ignored here, but implemented because sent without checking 

    "/ when parsing keyword messages to an optimized messageNode

    "/ (which become optimized to a constantNode by the folder)

    "Created: / 28-08-2013 / 21:17:22 / cg"

!

selectorPosition:aCharacterPosition

    "ignored here"

    "Created: 5.8.1997 / 16:32:17 / cg"

!

startPosition

    ^ startPosition

!

startPosition:start

    startPosition := start

    "Modified: / 08-04-2011 / 22:03:43 / Jan Vrany <jan.vrany@fit.cvut.cz>"

!

startPosition:start endPosition: end

    startPosition := start.

    endPosition := end.

    ^self

    "Created: / 11-07-2011 / 17:44:11 / Jan Vrany <jan.vrany@fit.cvut.cz>"

!

type

    "return the nodes type"

    ^ type

! !

!ParseNode methodsFor:'attributes access'!

objectAttributes

    ^attributes

    "Created: / 09-07-2011 / 12:17:55 / Jan Vrany <jan.vrany@fit.cvut.cz>"

!

objectAttributes: anObject

    attributes := anObject

    "Created: / 09-07-2011 / 12:18:08 / Jan Vrany <jan.vrany@fit.cvut.cz>"

! !

!ParseNode methodsFor:'checks'!

plausibilityCheckIn:aParser

    ^ nil

! !

!ParseNode methodsFor:'code generation'!

codeForSideEffectOn:aStream inBlock:b for:aCompiler

    "generate code for this statement - value not needed"

    self codeOn:aStream inBlock:b for:aCompiler.

    aStream nextPut:#drop

!

codeForSimpleReturnOn:aStream inBlock:b lineNumber:lineNrOrNil for:aCompiler

    "generate code to return myself as a simple method return"

    self codeOn:aStream inBlock:b for:aCompiler.

    lineNrOrNil notNil ifTrue:[

        self codeLineNumber:lineNrOrNil on:aStream for:aCompiler

    ].

    aStream nextPut:#retTop.

!

codeInlineOn:aStream inBlock:b valueNeeded:valueNeeded for:aCompiler

    "generate code for this statement - value is needed"

    self codeOn:aStream inBlock:b for:aCompiler.

!

codeLineNumber:nr on:codeStream for:aCompiler

    "generate lineNumber information"

    aCompiler codeLineNumber:nr on:codeStream

!

codeOn:aStream inBlock:codeBlock for:aCompiler

    ^ self subclassResponsibility

! !

!ParseNode methodsFor:'code generation helpers'!

emitPushGlobalWithLiteralIndex:litIndex on:aTokenCodeStream for:aCompiler

    litIndex <= 255 ifTrue:[

        aTokenCodeStream nextPut:#pushGlobalS; nextPut:litIndex

    ] ifFalse:[

        litIndex <= 16rFFFF ifTrue:[

            aTokenCodeStream nextPut:#pushGlobalL; nextPut:litIndex; nextPut:0

        ] ifFalse:[

            aTokenCodeStream nextPut:#pushGlobalVL; nextPut:0; nextPut:litIndex; nextPut:0; nextPut:0; nextPut:0

        ].

    ].

!

emitPushLiteral:value on:aTokenCodeStream for:aCompiler

    |index|

    index := aCompiler addLiteral:value.

    self emitPushLiteralIndex:index on:aTokenCodeStream for:aCompiler

!

emitPushLiteralIndex:index on:aTokenCodeStream for:aCompiler

    index <= 8 ifTrue:[

        aTokenCodeStream 

            nextPut:(#(pushLit1 pushLit2 pushLit3 pushLit4

                       pushLit5 pushLit6 pushLit7 pushLit8) at:index).

    ] ifFalse:[

        index <= 255 ifTrue:[

            aTokenCodeStream nextPut:#pushLitS; nextPut:index

        ] ifFalse:[

            index <= 16rFFFF ifTrue:[

                aTokenCodeStream nextPut:#pushLitL; nextPut:index; nextPut:0

            ] ifFalse:[

                aTokenCodeStream nextPut:#pushLitVL; nextPut:0; nextPut:index; nextPut:0; nextPut:0; nextPut:0

            ]

        ].

    ].

!

emitSendLiteralIndex:litIndex numArgs:nargs line:lineNr on:aStream for:aCompiler

    lineNr >= 255 ifTrue:[

        self codeLineNumber: lineNr on: aStream for:aCompiler.  

    ].

    (litIndex <= 255) ifTrue:[

        nargs <= 3 ifTrue:[

            aStream 

                nextPut:(#(send0 send1 send2 send3) at:(nargs+1)); nextPut:lineNr; 

                nextPut:litIndex.

            ^ self.

        ].

        aStream 

            nextPut:#send; nextPut:lineNr; 

            nextPut:litIndex; 

            nextPut:nargs.

        ^ self.

    ].

    (litIndex <= 16rFFFF) ifTrue:[

        aStream 

            nextPut:#sendL; nextPut:lineNr; 

            nextPut:litIndex; nextPut:0; 

            nextPut:nargs.

        ^ self.

    ].

    aStream 

        nextPut:#sendVL; nextPut:0; nextPut:lineNr; 

        nextPut:litIndex; nextPut:0; nextPut:0; nextPut:0; 

        nextPut:nargs.

    "Modified: / 13-04-2013 / 11:02:20 / Jan Vrany <jan.vrany@fit.cvut.cz>"

!

emitStoreGlobalWithLiteralIndex:litIndex on:aTokenCodeStream for:aCompiler

    litIndex <= 255 ifTrue:[

        aTokenCodeStream nextPut:#storeGlobalS; nextPut:litIndex

    ] ifFalse:[

        litIndex <= 16rFFFF ifTrue:[

            aTokenCodeStream nextPut:#storeGlobalL; nextPut:litIndex; nextPut:0

        ] ifFalse:[

            aTokenCodeStream nextPut:#storeGlobalVL; nextPut:0; nextPut:litIndex; nextPut:0; nextPut:0; nextPut:0; nextPut:0

        ].

    ].

!

emitSuperSendLiteralIndex:litIndex classLiteralIndex:clsLitIndex numArgs:nargs line:lineNr on:aStream for:aCompiler

    lineNr >= 255 ifTrue:[

        self codeLineNumber: lineNr on: aStream for:aCompiler.  

    ].

    (litIndex <= 255 and:[clsLitIndex <= 255]) ifTrue:[

        aStream 

            nextPut:#superSend; nextPut:lineNr; 

            nextPut:litIndex; 

            nextPut:nargs; 

            nextPut:clsLitIndex.

    ] ifFalse:[

        (litIndex <= 16rFFFF and:[clsLitIndex <= 16rFFFF]) ifTrue:[

            aStream 

                nextPut:#superSendL; nextPut:lineNr; 

                nextPut:litIndex; nextPut:0; 

                nextPut:nargs; 

                nextPut:clsLitIndex; nextPut:0.

        ] ifFalse:[

            aStream 

                nextPut:#superSendVL; nextPut:0; nextPut:lineNr; 

                nextPut:litIndex; nextPut:0; nextPut:0; nextPut:0;

                nextPut:nargs; 

                nextPut:clsLitIndex; nextPut:0; nextPut:0; nextPut:0.

        ].

    ].

    "Modified: / 13-04-2013 / 11:01:51 / Jan Vrany <jan.vrany@fit.cvut.cz>"

! !

!ParseNode methodsFor:'enumeration'!

messageNodesDo:aBlock

    "evaluate aBlock for each message-node here and in subnodes"

    ^ self

!

messageSelectors

    "return a collection of message seelctors"

    |setOfSymbols|

    setOfSymbols := Set new.

    self messageSelectorsDo:[:each | setOfSymbols add:each ].

    ^ setOfSymbols

!

messageSelectorsDo:aBlock

    "evaluate aBlock for each message-selector here and in subnodes"

    ^ self

!

messages

    "return a collection of messageNodes"

    |setOfMessages|

    setOfMessages := Set new.

    self messagesDo:[:each | setOfMessages add:each ].

    ^ setOfMessages

!

messagesDo:aBlock

    "evaluate aBlock for each message-node here and in subnodes"

    ^ self

! !

!ParseNode methodsFor:'evaluation'!

evaluate

    ^ self evaluateIn:nil

!

evaluateForCascade

    ^ self evaluateForCascadeIn:nil

!

evaluateForCascadeIn:anEnvironment

    ^ self evaluateIn:anEnvironment

!

evaluateIn:anEnvironment

    self subclassResponsibility

!

isStatement

^false.

    "Created: / 22-02-2011 / 16:29:50 / Jakub <zelenja7@fel.cvut.cz>"

! !

!ParseNode methodsFor:'printing & storing'!

printOn:aStream

    "append a user printed representation of the receiver to aStream.

     The format is suitable for a human - not meant to be read back."

    self printOn:aStream indent:0

!

printOn:aStream indent:indent

    "append a user printed representation of the receiver to aStream.

     The format is suitable for a human - not meant to be read back."

    self subclassResponsibility

    "Created: / 20-04-2005 / 14:21:46 / cg"

!

printOn:aStream indent:indent parenthized:parenthized

    parenthized ifTrue:[

        aStream nextPutAll:'('

    ].

    self printOn:aStream indent:indent.

    parenthized ifTrue:[

        aStream nextPutAll:')'

    ].

    "Created: / 20-04-2005 / 14:21:28 / cg"

! !

!ParseNode methodsFor:'private'!

type:t

    "set the nodes type"

    type := t

! !

!ParseNode methodsFor:'queries'!

canReuseAsArg:anotherNode

    ^ false

    "Created: 14.4.1996 / 00:43:08 / cg"

!

collectBlocksInto:aCollection

    ^ self

    "Created: 23.10.1996 / 15:45:00 / cg"

!

containsReturn

    ^ false

!

positionToInsertPeriodForStatementSeparation

    ^ self endPosition + (parenthized == true ifTrue:1 ifFalse:0)

    "Created: 14.4.1996 / 00:43:08 / cg"

!

precedence

    ^ 9999

!

withConstantValueDo:aBlock

    "return true, if this evaluates to a constant value

     and evaluate aBlock with it"

    ^ false

! !

!ParseNode methodsFor:'testing'!

isAssignment

    "return true, if this is a node for an assignment"