RFR: 8320682: [AArch64] C1 compilation fails with "Field too big for insn" [v3]

[Daniel Lundén]

On Fri, 8 Dec 2023 02:29:29 GMT, Dean Long <dlong at openjdk.org> wrote:

>> Daniel Lundén has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   Update copyright
>
> test/hotspot/jtreg/compiler/arguments/TestC1Globals.java line 62:
> 
>> 60:  *          Linux.
>> 61:  *
>> 62:  * @run main/othervm -XX:NMethodSizeLimit=351658240
> 
> What were these large sizes of NMethodSizeLimit meant to test?  Removing these test cases because of a problem with aarch64 seems wrong, unless these test cases really have no value for other platforms.

Thanks for the review @dean-long. I added these tests recently for [JDK-8318817](https://bugs.openjdk.org/browse/JDK-8318817) and [JDK-8316653](https://bugs.openjdk.org/browse/JDK-8316653). From what I've gathered since then, there is little reason to allow such large values for NMethodSizeLimit. Do you know of any use case that requires more than 1MB? If not, I would say 1MB is probably a sensible upper bound, as it deals with this issue and also other potential issues due to code cache size assumptions (not only on aarch64).

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PR Review Comment: https://git.openjdk.org/jdk/pull/16951#discussion_r1420477576