Float math in VMMaker-dtl.123

>
> I just noticed that
>
> bytecodePrimGreaterOrEqual
>     ...
>     aBool := self primitiveFloatLess: rcvr thanArg: arg.
>     successFlag ifTrue: [^self booleanCheat: aBool not].
>
> got changed to
>
> bytecodePrimGreaterOrEqual
>     ...
>     aBool := self primitiveFloatGreaterOrEqual: rcvr toArg: arg.
>     successFlag ifTrue: [^self booleanCheat: aBool not].
>
> but shouldn't that be
>
> bytecodePrimGreaterOrEqual
>     ...
>     aBool := self primitiveFloatGreaterOrEqual: rcvr toArg: arg.
>     successFlag ifTrue: [^self booleanCheat: aBool].
>
> and similarly for bytecodePrimLessOrEqual?
>
> - Bert -
>
>

>
> Bert Freudenberg wrote:
> >
> >I just noticed that
> >
> >bytecodePrimGreaterOrEqual
> >    ...
> >    aBool := self primitiveFloatLess: rcvr thanArg: arg.
> >    successFlag ifTrue: [^self booleanCheat: aBool not].
> >
> >got changed to
> >
> >bytecodePrimGreaterOrEqual
> >    ...
> >    aBool := self primitiveFloatGreaterOrEqual: rcvr toArg: arg.
> >    successFlag ifTrue: [^self booleanCheat: aBool not].
> >
> >but shouldn't that be
> >
> >bytecodePrimGreaterOrEqual
> >    ...
> >    aBool := self primitiveFloatGreaterOrEqual: rcvr toArg: arg.
> >    successFlag ifTrue: [^self booleanCheat: aBool].
> >
> >and similarly for bytecodePrimLessOrEqual?
> >
> >- Bert -
> >
> >

>
> On Wed, Jul 01, 2009 at 08:32:18AM -0700, Andreas Raab wrote:
>>
>> Ouch. Yeah, I'd say that's right...
>
> This is from http://bugs.squeak.org/view.php?id=7260. I reopened the
> issue on Mantis.
>
> I'll apply the fix to VMMaker as soon as I can (but feel free to do the
> update if I don't get to it first; Bert you have developer access as well
> as Andreas of course).
>
> Dave
>

>>
>> Bert Freudenberg wrote:
>> >
>> >I just noticed that
>> >
>> >bytecodePrimGreaterOrEqual
>> >    ...
>> >    aBool := self primitiveFloatLess: rcvr thanArg: arg.
>> >    successFlag ifTrue: [^self booleanCheat: aBool not].
>> >
>> >got changed to
>> >
>> >bytecodePrimGreaterOrEqual
>> >    ...
>> >    aBool := self primitiveFloatGreaterOrEqual: rcvr toArg: arg.
>> >    successFlag ifTrue: [^self booleanCheat: aBool not].
>> >
>> >but shouldn't that be
>> >
>> >bytecodePrimGreaterOrEqual
>> >    ...
>> >    aBool := self primitiveFloatGreaterOrEqual: rcvr toArg: arg.
>> >    successFlag ifTrue: [^self booleanCheat: aBool].
>> >
>> >and similarly for bytecodePrimLessOrEqual?
>> >
>> >- Bert -
>> >
>> >
>

>
> 2009/7/1 David T. Lewis <[hidden email]>:
>>
>> On Wed, Jul 01, 2009 at 08:32:18AM -0700, Andreas Raab wrote:
>>>
>>> Ouch. Yeah, I'd say that's right...
>>
>> This is from http://bugs.squeak.org/view.php?id=7260. I reopened the
>> issue on Mantis.
>>
>> I'll apply the fix to VMMaker as soon as I can (but feel free to do  
>> the
>> update if I don't get to it first; Bert you have developer access  
>> as well
>> as Andreas of course).
>>
>> Dave
>>
>
> Ouch again, my fault.
> How can the tests pass... Hmm not enough test?

>
>  Hi Bert,  All,
>     Hold on!
>
> On Wed, Jul 1, 2009 at 11:52 AM, Bert Freudenberg <[hidden email]> wrote:
>>
>>
>> On 01.07.2009, at 19:02, Nicolas Cellier wrote:
>>
>>>
>>> 2009/7/1 David T. Lewis <[hidden email]>:
>>>>
>>>> On Wed, Jul 01, 2009 at 08:32:18AM -0700, Andreas Raab wrote:
>>>>>
>>>>> Ouch. Yeah, I'd say that's right...
>>>>
>>>> This is from http://bugs.squeak.org/view.php?id=7260. I reopened the
>>>> issue on Mantis.
>>>>
>>>> I'll apply the fix to VMMaker as soon as I can (but feel free to do the
>>>> update if I don't get to it first; Bert you have developer access as well
>>>> as Andreas of course).
>>>>
>>>> Dave
>>>>
>>>
>>> Ouch again, my fault.
>>> How can the tests pass... Hmm not enough test?
>>
>>
>> the failure would only be triggered for code like
>>
>> 0.1 <= 0.2 ifTrue: [...]
>>
>> but not for
>>
>> self assert: 0.1 <= 0.2
>
> That's not my reading of booleanCheat:.  booleanCheat: takes a C boolean argument cond.  If the following bytecodes are those of a conditional branch then it either takes or skips those bytecodes based on the value of cond, otherwise it reifies cond as either true or false.  i.e. the jump and reification behaviours match (duh!).  So I think it *does* show up in both
>     0.1 <= 0.2 ifTrue: [...]
> and
>     self assert: 0.1 <= 0.2
> Further, the comment I have in my versions is I think correct:
> bytecodePrimGreaterOrEqual
> | rcvr arg aBool |
> rcvr := self internalStackValue: 1.
> arg := self internalStackValue: 0.
> (self areIntegers: rcvr and: arg) ifTrue:
> ["The C code can avoid detagging since tagged integers are still signed.
> But this means the simulator must override to do detagging."
> self cCode: '' inSmalltalk: [^self booleanCheat: (self integerValueOf: rcvr) >= (self integerValueOf: arg)].
> ^self booleanCheat: rcvr >= arg].
> successFlag := true.
>>> "Invert test so that NaN comparisons work correctly."
> aBool := self primitiveFloatLess: rcvr thanArg: arg.
> successFlag ifTrue: [^self booleanCheat: aBool not]
> Because
>     | aNaN | aNaN := Float nan.  nan >= nan
> must be false (since nan ~= nan) and because
>     | aNaN | aNaN := Float nan.  nan < nan