[aarch64-port-dev ] Field too big for insn issue with Shenandoah

[Andrew Haley]

On 09/10/2018 04:11 PM, Roman Kennke wrote:
> This only happens when running with Shenandoah. I suspect that the extra
> barriers that we emit with Shenandoah make the code too big and the PC
> too far away from the constants, but I am not sure.

Nice catch! I always knew that this was a theoretical possibility, but
I never could find a way to trigger it.

> Does anybody have an idea why that happens and how to possibly fix it?

I'll have a look. It's going to be very awkward if loads can't reach the
constant pool. The load offset is 19 bits, shifted by 2, so that's +/- a
megabyte. I don't really believe that any method will generate a megabyte
of code, so I suspect that there may be some other reason. Perhaps enabling
debug mode just generates too much checking code.

Which test was running?

-- 
Andrew Haley
Java Platform Lead Engineer
Red Hat UK Ltd. <https://www.redhat.com>
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