Putting this in the inbox for review in case there may be some
performance impact (I don't think so, but better to be safe).

Dave


On Fri, Nov 26, 2021 at 04:06:22PM +0000, commits at source.squeak.org wrote:
> A new version of System was added to project The Inbox:
> http://source.squeak.org/inbox/System-dtl.1254.mcz
> 
> ==================== Summary ====================
> 
> Name: System-dtl.1254
> Author: dtl
> Time: 26 November 2021, 11:06:19.584405 am
> UUID: 3856329c-1404-4bd5-9b94-d9c47f663d7c
> Ancestors: System-mt.1253
> 
> Let vmParameterAt:ifAbsent: treat nil as an absent parameter. Previously only out of range parameter requests were treated as absent.
> 
> Handles the case of parameter 54 which is numeric for Spur VM, nil for Cog VM, and out of range for interpreter VM. Update bytesUsedString to use 0 as default for parameter 54.
> 
> =============== Diff against System-mt.1253 ===============
> 
> Item was changed:
>   ----- Method: SmalltalkImage>>bytesUsedString (in category 'memory space') -----
>   bytesUsedString
>   	"Answer a string describing the amount of memory in use."
>   	"Smalltalk bytesUsedString"
>   	| totalUsed |
>   	totalUsed := (self vmParameterAt: 2 "used eden + used past space")
> + 				+ ((self vmParameterAt: 1 "old space size")
> + 				- (self vmParameterAt: 54 ifAbsent: 0 "free old space")).
> - 				+ ((self vmParameterAt: 1 "old space size") - (self vmParameterAt: 54 "free old space")).
>   	^totalUsed asStringWithCommas, ' bytes in use'!
> 
> Item was changed:
>   ----- Method: SmalltalkImage>>vmParameterAt:ifAbsent: (in category 'vm parameters') -----
>   vmParameterAt: parameterIndex ifAbsent: defaultValueOrBlock
> + 	"Answer a VM parameter or defaultValueOrBlock value if out of range
> + 	or if the VM does not provide a value for this parameter. A VM parameter
> + 	is typically numeric or boolean, and if not implemented will be nil."
> + 	^ [(self vmParameterAt: parameterIndex)
> + 			ifNil: defaultValueOrBlock value]
> - 	"Answer a VM parameter or defaultValueOrBlock value if out of range."
> - 	^ [self vmParameterAt: parameterIndex]
>   		on: Error
>   		do: [defaultValueOrBlock value]!
> 
>