AArch64: is a compressed class space at 2G a problem?

[Reingruber, Richard]

> On 12/18/20 4:52 PM, Reingruber, Richard wrote:
> > 
> > it appears to me that locating the compressed class space (ccs) at 2G is
> > currently not possible on AArch64 [1][2]. This looks like a bug to me. Would you
> > agree?

> If the compressed class space is located at 2G then its encoding
> base should be zero. We don't care exactly where the space starts,
> but we do care very much that its encoding base is 4G-aligned.

Thanks for the feedback! I've created [1] to track this.

Richard.

[1] https://bugs.openjdk.java.net/browse/JDK-8258756

-----Original Message-----
From: hotspot-dev <hotspot-dev-retn at openjdk.java.net> On Behalf Of Andrew Haley
Sent: Samstag, 19. Dezember 2020 11:56
To: hotspot-dev at openjdk.java.net
Subject: Re: AArch64: is a compressed class space at 2G a problem?

On 12/18/20 4:52 PM, Reingruber, Richard wrote:
> 
> it appears to me that locating the compressed class space (ccs) at 2G is
> currently not possible on AArch64 [1][2]. This looks like a bug to me. Would you
> agree?

If the compressed class space is located at 2G then its encoding
base should be zero. We don't care exactly where the space starts,
but we do care very much that its encoding base is 4G-aligned.

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