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

[Nick Gasson]

On 29/11/2019 11:41, Pengfei Li (Arm Technology China) wrote:
> 
> The 4G alignment search may still fail after the fix. Regarding to my second webrev, do you agree that checking the base and shift values in a function in aarch64.ad? See my last email [1] for detail explanations.
> 

How about we exit with a fatal error if we can't find a suitably aligned 
region? Then we can remove the code in decode_klass_non_null that uses 
R27 and this patch is much simpler. That code path is poorly tested at 
the moment so it seems risky to leave it in. With a hard error at least 
users will report it to us so we can fix it.

Thanks,
Nick