[8u] RFR 8248901: Signed immediate support in .../share/assembler.hpp is broken.

[Andrew Haley]

On 6/23/21 9:46 AM, Andrew Dinn wrote:

> On 22/06/2021 15:20, Zhengyu Gu wrote:
>> I would like to backport this patch to openjdk8u for parity with Oracle 
>> 8u291.

Parity only really makes sense in the context of bug fixes.

>> The original patch does not apply cleanly.
>>
>> - openjdk8u does not have arm (32-bit) port, striped arm specific 
>> changes from the patch.
>> - "precond" macro is not defined in openjdk8u, replaced with assert(...).
>>
>> Original bug: https://bugs.openjdk.java.net/browse/JDK-8248901
>> Original patch: https://hg.openjdk.java.net/jdk/jdk/rev/ce8fb40c9174
>>
>> 8u webrev: http://cr.openjdk.java.net/~zgu/JDK-8248901-8u/webrev.00/
> The webrev above still includes two occurrences of precond.

I'm not convinced we need this backport at all. It doesn't fix any bugs,
and is only used for the one-liner is_uimm12 in the fix for 8247766. This
patch is harmless, but we should at least think about the churn in 8u.

-- 
Andrew Haley  (he/him)
Java Platform Lead Engineer
Red Hat UK Ltd. <https://www.redhat.com>
https://keybase.io/andrewhaley
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