Request for review(XS): 7013812: C1: deopt blob too far from patching stub

Tom Rodriguez tom.rodriguez at
Thu Jan 20 22:09:32 PST 2011

Actually, how does this happen?  deopt blob and patching stubs are created pretty early so how could they be that far apart?  The branch has a signed reach of 22 bits worth of words so it can reach +/- 8M.  How could there be 8M between the deopt blob and the patching stub?


On Jan 20, 2011, at 9:45 PM, Igor Veresov wrote:

> After a bit of a thought, I decided to leave the 32bit as it was.
> Webrev updated:
> igor
> On 1/20/11 9:28 PM, Igor Veresov wrote:
>> access_filed_patching and load_klass_patching stubs are using
>> effectively a bp instruction to jump to deopt blob. This limits the
>> distance between the deopt blob and these stub to 2^20, which is not
>> enough. Since this situation could become possible also with a 32bit VM
>> (the distance is only 1M), I decided to always use long jumps.
>> Webrev:
>> Thanks,
>> igor

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