[aarch64-port-dev ] RFR: 8179933: aarch64: incorrect match rule for immL_63 and immL_255

[Andrew Dinn]

On 12/05/17 10:25, Andrew Haley wrote:
> On 12/05/17 10:14, Zhongwei Yao wrote:
>> On 12 May 2017 at 16:14, Andrew Haley <aph at redhat.com> wrote:
>>> So it's
>>>
>>>    ((aLong >> 63) >>> 63)
>>>
>>> This is so weird I don't know what to think about it.
>>
>> Yeah, it is weird. I was thinking (aLong >>> 63) should be enough. Shall we
>> just remove this pattern?
> 
> Well, maybe there was a reason for it.

Ok, these rules were first introduced into jdk8 by Ed Nevill

  http://hg.openjdk.java.net/aarch64-port/jdk8u/hotspot/rev/1fcabae0e46f

They were then imported into jdk9 as part of the wholesale upload.

So, I think there is probably a good reason why they are there :-)

regards,


Andrew Dinn
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