[aarch64-port-dev ] RFR(M): 8233743: AArch64: Make r27 conditionally allocatable

[Andrew Haley]

On 11/18/19 10:35 AM, Pengfei Li (Arm Technology China) wrote:
> If this is true, UseCompressedClassPointers cannot be used without
> UseCompressedOops. So wouldn't a single condition of UseCompressedOops be
> enough?

Why do you think so? UseCompressedOops doesn't usually need r27.

> But the x86_64 code which I referenced has both two conditions.
> Is it because the relationship of the arguments are subject to change in the
> future?

I have no idea why these flags depend on each other. I'd use compressed
class pointers all the time, regardless of compressed oops.

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