Request for reviews (M): 6954029: Improve implicit null check generation with compressed oops
vladimir.kozlov at oracle.com
Fri May 21 10:48:22 PDT 2010
I found bug in the code. x64 DecodeN may change flags
I have to hoist flag-killing projections:
Only opto/lcm.cpp was changed vs previous webrev.
Vladimir Kozlov wrote:
> Thank you, Christian
> I fixed typo.
> Christian Thalinger wrote:
>> On Thu, 2010-05-20 at 18:02 -0700, Vladimir Kozlov wrote:
>>> Fixed 6954029: Improve implicit null check generation with compressed
>>> 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.
>>> 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).
>> + assert(UseCompressedOops, "only for comressed oops code");
>> ^ typo
>> Otherwise (I think) it's OK.
>> -- Christian
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