RFR(S)[13]: AArch64: float point register corruption in ZBarrierSetAssembler::load_at

[Andrew Haley]

On 6/21/19 5:02 PM, Stuart Monteith wrote:
>    I'm trying passing r19 instead of rscratch1 to __ load_mirror and
> also checking that rscratch1,2 aren't passed to load_at. That would
> free up rscratch1 and 2 to be used, and not saved, in load_at.

Yes. Better.

> The tmp register is more often than not set to rscratch2 or noreg,
> so it isn't a terribly useful parameter.

Huh? It makes no sense to pass noreg as a tmp. A callee has a right
to assume that a reg passed as tmp can be used.

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