"

 COPYRIGHT (c) 2010 by Jan Vrany, SWING Research Group. CTU in Prague

	      All Rights Reserved

Permission is hereby granted, free of charge, to any person

obtaining a copy of this software and associated documentation

files (the 'Software'), to deal in the Software without

restriction, including without limitation the rights to use,

copy, modify, merge, publish, distribute, sublicense, and/or sell

copies of the Software, and to permit persons to whom the

Software is furnished to do so, subject to the following

conditions:

The above copyright notice and this permission notice shall be

included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND,

EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES

OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND

NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT

HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,

WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING

FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR

OTHER DEALINGS IN THE SOFTWARE.

"

"{ Package: 'stx:libbasic' }"

"{ NameSpace: Smalltalk }"

Object subclass:#Lookup

	instanceVariableNames:''

	classVariableNames:''

	poolDictionaries:''

	category:'Kernel-Extensions'

!

!Lookup class methodsFor:'documentation'!

copyright

"

 COPYRIGHT (c) 2010 by Jan Vrany, SWING Research Group. CTU in Prague

	      All Rights Reserved

Permission is hereby granted, free of charge, to any person

obtaining a copy of this software and associated documentation

files (the 'Software'), to deal in the Software without

restriction, including without limitation the rights to use,

copy, modify, merge, publish, distribute, sublicense, and/or sell

copies of the Software, and to permit persons to whom the

Software is furnished to do so, subject to the following

conditions:

The above copyright notice and this permission notice shall be

included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND,

EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES

OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND

NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT

HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,

WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING

FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR

OTHER DEALINGS IN THE SOFTWARE.

"

! !

!Lookup class methodsFor:'initialization'!

initialize

    "/ do we really need this?

    "/ i.e. my own messages can be resolved by the VM - can't they ?

    "/ self lookupObject: Lookup builtin

    "Created: / 26-04-2010 / 21:15:18 / Jan Vrany <jan.vrany@fit.cvut.cz>"

! !

!Lookup class methodsFor:'accessing'!

builtin

    ^BuiltinLookup instance

    "Created: / 26-04-2010 / 19:26:21 / Jan Vrany <jan.vrany@fit.cvut.cz>"

! !

!Lookup methodsFor:'lookup'!

lookupMethodForSelector: selector directedTo: initialSearchClass

    |cls md method|

    "Following C code is just a performance optimization.

     It is not necessary, however it speeds up UI code,

     since it heavily uses perform:"

%{

    RETURN (  __lookup(initialSearchClass, selector) );

%}.

    cls := initialSearchClass.

    [ cls notNil ] whileTrue:[

       md := cls methodDictionary.

       method := md at:selector ifAbsent:nil.

       method notNil ifTrue:[^ method ].

       cls := cls superclass.

    ].

    ^ nil

    "Created: / 27-04-2010 / 15:30:24 / Jan Vrany <jan.vrany@fit.cvut.cz>"

!

lookupMethodForSelector:selector directedTo:initialSearchClass for:aReceiver withArguments:argArrayOrNil from:sendingContext

    <resource: #obsolete>

    "

     This method is no longer sent by the VM as it nows pass

     inline/poly cache object.

    "

    "invoked by the VM to ask me for a method to call.

     The arguments are: the selector, receiver and arguments,

     the class to start the search in (for here-, super and directed sends)

     the sending context.

     The returned method object will be put into the inline- and polyCache

     at the call site; it might therefore be called more than once for the

     same receiver-class/selector combination (once for each call site).

     If I return nil, a doesNotUnderstand will be invoked."

     |cls md method|

    "Following C code is just a performance optimization.

     It is not necessary, however it speeds up UI code,

     since it heavily uses perform:"

%{

    RETURN (  __lookup(initialSearchClass, selector) );

%}.

    ^ self lookupMethodForSelector: selector

                   directedTo: initialSearchClass

!

lookupMethodForSelector:selector directedTo:initialSearchClass for:aReceiver withArguments:argArrayOrNil from:sendingContext ilc: ilcCache

    "Invoked by the VM to ask me for a method to call.

     The arguments are: the selector, receiver and arguments,

     the class to start the search in (for here-, super and directed sends)

     the sending context and the inline/poly cache (instance of

         PolymorphicInlineCache).

     The returned method object will NOT be put into the inline- and

         polyCache bu default. To update the call site's cache, you have to

         call ilcCache bindTo: method forClass: initialSearch class. If you

         don't call it, inline/poly cache won't be updated and next call

         won't be cached (therefore it will be relatively slow.

     If I return nil, a doesNotUnderstand: will be send."

    | method |

    "Following C code is just a performance optimization.

     It is not necessary, however it speeds up UI code,

     since it heavily uses perform:"

%{

    method = __lookup(initialSearchClass, selector);

    if ( method ) {

        __ilcBind(ilcCache, initialSearchClass, method, selector);

    }

    RETURN (method);

%}.

    method := self lookupMethodForSelector:selector directedTo:initialSearchClass for:aReceiver withArguments:argArrayOrNil from:sendingContext.

    ilcCache notNil ifTrue:[

        ilcCache bindTo: method forClass: initialSearchClass.

    ].

    ^ method.

    "Created: / 01-10-2011 / 13:18:40 / Jan Kurs <kursjan@fit.cvut.cz>"

! !

!Lookup class methodsFor:'documentation'!

version_CVS

    ^ '$Header$'

!

version_SVN

    ^ '$Id$'

! !

Lookup initialize!