[Vm-dev] positive32BitValueOf: fail with LargePositiveInteger

[Levente Uzonyi]

On Fri, 8 Oct 2010, David T. Lewis wrote:

>
> On Fri, Oct 08, 2010 at 07:12:13PM +0200, Mariano Martinez Peck wrote:
>>
>> So....I don't understand...how can I have a LargePositiveInteger but that is
>> less than 32 bits?  Wouldn't that  be a SmallInteger?
>
> SmallInteger maxVal hex ==> '16r3FFFFFFF'.
>
> The largest positive two-compliment integer that fits into 32 bits is
> 16rEFFFFFFF, so any Integer in the range 16r4000000 through 16rEFFFFFFF
> is a LargePositiveInteger that can fit into a signed 32-bit C int.
>
> Thus the number of LargePositiveInteger values that fit into a 32-bit
> twos-compliment representation is (16r4000000 to: 16rEFFFFFFF) size ==> 3959422976
>
> Note that a SmallInteger is represented internally as a 31-bit value,
> which accounts for the difference. It's a bit confusing when you are used
> to thinking of 32-bit int values.

Shouldn't those 16rEFFFFFFF's be 167FFFFFF?


Levente

>
> Dave
>
>