RFR: 8231754: [JVMCI] Make r27 unconditionally reserved in JVMCI

[Gilles Duboscq]

The idea was to first bring JVMCI in line with what the other compilers do (never allocate r27) and then investigate how we could make r27 conditionally allocatable if there is interest.

  Gilles

On 11/10/2019 07:47, dean.long at oracle.com wrote:
> Wouldn't it be better to make r27 callee-saved in cpu/aarch64/sharedRuntime_aarch64.cpp:RegisterSaver::save_live_registers()?
> 
> dl
> 
> On 10/10/19 6:43 PM, Pengfei Li (Arm Technology China) wrote:
>> FW aarch64-port-dev as this is AArch64 related.
>>
>> -- 
>> Thanks,
>> Pengfei
>>
>>> Hello,
>>>
>>> Please review the following small change to reserve r27 (heap base
>>> register) on AArch64 unconditionally, i.e., regardless of whether compressed
>>> oops is enabled or not.
>>>
>>> http://cr.openjdk.java.net/~yzheng/8231754/
>>> https://bugs.openjdk.java.net/browse/JDK-8231754
>>>
>>> Many thanks,
>>> -Yudi
>