[aarch64-port-dev ] RFR(S): 8241091: AArch64: "bad AD file" with VM option "-XX:-UsePopCountInstruction"

[Andrew Haley]

On 3/20/20 8:40 AM, Pengfei Li wrote:
> Hi Andrew,
> 
>> We could go either way, but there's no point in disabling popcount on
>> AArch64. So [2], but please produce an error message if "-
>> UsePopCountInstruction" is used.
> 
> My understanding of your "error message" is a warning message instead of a hard error, as current "bad AD file" is already a hard error.
> 
> The general option UsePopCountInstruction is false by default. In my updated webrev [1], the default value is changed to true for AArch64 and a warning is printed if it's turned off manually.
> 
> $ java Foo
> 219504
> $ java -XX:-UsePopCountInstruction Foo
> OpenJDK 64-Bit Server VM warning: UsePopCountInstruction is always enabled on this CPU
> 219504
> 
> Jtreg tier1 passed. Is this ok?
> 
> [1] http://cr.openjdk.java.net/~pli/rfr/8241091/webrev.02/

Yes, thanks.

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