Request for reviews (M): 6954029: Improve implicit null check generation with compressed oops

[Vladimir Kozlov]

Thank you, Christian

I fixed typo.

Vladimir

Christian Thalinger wrote:
> On Thu, 2010-05-20 at 18:02 -0700, Vladimir Kozlov wrote:
>> http://cr.openjdk.java.net/~kvn/6954029/webrev
>>
>> Fixed 6954029: Improve implicit null check generation with compressed oops
>>
>> Problem:
>> When DecodeN instruction does not fold into address expression
>> it may prevent implicit null check generation if it is scheduled
>> below the null check since the corresponding memory instruction
>> could not be moved.
>>
>> Solution:
>> If needed move DecodeN instruction before null check to generate
>> implicit null check.
>>
>> I also removed code which switch off default COOP usage on N1:
>> currently generated COOP code perform better on N1 (tested jbb2005).
> 
> src/cpu/sparc/vm/sparc.ad:
> src/cpu/x86/vm/x86_64.ad:
> 
> +   assert(UseCompressedOops, "only for comressed oops code");
>                                            ^ typo
> 
> Otherwise (I think) it's OK.
> 
> -- Christian
>