8248336: AArch64: C2: offset overflow in BoxLockNode::emit

[Andrew Haley]

BoxLockNode::emit only allows a 12-bit offset from register SP to the
stack slot that contains the inflated lock. Rather amazingly we've
never seen this fail in production, but in theory a BoxLockNode can be
anywhere in the stack frame.

I have once seen this fail in test code, but it is very hard to
reproduce.

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