Fix unlikely but possible race in `WeakValueDictionary`
It may happen that value in `valueArray` could have been already
collected by the GC but #clearDeadSlots have not yet been called.
When this happened, `#at:ifAbsentPut:` returned tombstone rather
than updating the dictionary with value from block.
This commit fixes this by checking whether `valueArray` contain
the tombstone and if so, clearing up the dead slots and restarting
the operation. HTH.
"
COPYRIGHT (c) 1997 eXept Software AG
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:libbasic' }"
"{ NameSpace: Smalltalk }"
UnboxedIntegerArray variableSignedWordSubclass:#SignedWordArray
instanceVariableNames:''
classVariableNames:''
poolDictionaries:''
category:'Collections-Arrayed'
!
!SignedWordArray class methodsFor:'documentation'!
copyright
"
COPYRIGHT (c) 1997 eXept Software AG
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
"
SignedWordArrays store 16bit signed integers in the range -16r8000..16r7FFF.
They are much like WordArrays, but the values stored are signed.
In contrast to normal arrays (which store pointers to their elements),
signedWordArrays store the values in a dense & compact way.
Since the representation fits the underlying C-language systems representation
of signed int16's, this is also useful to pass bulk data to c primitive code.
Therefore, SignedWordArrays can be used to hold bulk data in a more compact way.
For example:
Array new:100000 withAll:1
requires 400k of object memory;
in contrast,
SignedWordArray new:100000 withAll:1
only requires half of it.
[memory requirements:]
OBJ-HEADER + (size * 2)
[see also:]
ByteArray WordArray BooleanArray FloatArray DoubleArray Array
IntegerArray LongIntegerArray SignedLongIntegerArray
[author:]
Claus Gittinger
"
! !
!SignedWordArray class methodsFor:'queries'!
elementByteSize
"for bit-like containers, return the number of bytes stored per element.
Here, 2 is returned"
^ 2
"Created: / 15-09-2011 / 14:11:18 / cg"
!
maxVal
"the maximum value which can be stored in instances of me.
For SignedWordArrays, this is 16r7FFF (largest 16bit signed int)"
^ 16r7FFF
!
minVal
"the minimum value which can be stored in instances of me.
For SignedWordArrays, this is -16r8000 (smallest 16bit signed int)"
^ -16r8000
! !
!SignedWordArray class methodsFor:'documentation'!
version
^ '$Header$'
!
version_CVS
^ '$Header$'
! !