RFR(XL): 8185640: Thread-local handshakes

Andrew Haley aph at redhat.com
Thu Oct 26 08:58:31 UTC 2017

On 25/10/17 23:05, Doerr, Martin wrote:

> after looking at the bytecodes again, I remembered that ret is olny
> for jsr. I think polling should also be done for the regular
> returns.
> A poll at the beginning of TemplateTable::_return should do the
> job. Unfortunately, it doesn't fit into your dispatch scheme.

I'm wondering if this is a good idea at all: it could increase the
latency of taking a safepoint in bytecode.  Granted, it does avoid
some significant code bloat in the interpreter.

BTW, I don't understand why interpreted code doesn't simply read the
polling page.  Or we could even simply read-protect the bytecode
dispatch tables themselves.

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