Request for reviews (S): 6711117: Assertion in 64bit server vm (flat != TypePtr::BOTTOM,"cannot alias-analyze an untyped ptr")
Vladimir.Kozlov at Sun.COM
Mon Apr 6 16:18:58 PDT 2009
Tom Rodriguez wrote:
> The extra load of base can be eliminated too since you moved the check
> for != NULL outside.
> I don't understand this addition:
> && phase->type(base)->higher_equal(TypePtr::NOTNULL)
> Why does the base need to be NOTNULL?
You are right, it should be != NULL_PTR:
to avoid "NULL+off" address type.
> On Apr 6, 2009, at 3:33 PM, Vladimir Kozlov wrote:
>> Fixed 6711117: Assertion in 64bit server vm (flat !=
>> TypePtr::BOTTOM,"cannot alias-analyze an untyped ptr")
>> The assert is triggered by the eliminate AutoBox code which asks
>> an alias type of "NULL+off" address type.
>> It is caused by the memory node processing during IGVN before
>> its control edge which checks the address's nullness is processed.
>> Delay a memory node transformation if its control on IGVN worklist.
>> Delay a memory node transformation if its address on IGVN worklist.
>> Execute the eliminate AutoBox code only when the address is not NULL.
>> Use replace_node() instead of subsume_node() during macro nodes
>> expansion to put users of the old node on IGVN worklist.
>> Reviewed by:
>> Fix verified (y/n): y, bug test
>> Other testing:
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