RFR(s): 8154210: Zero: Better byte behaviour

[Severin Gehwolf]

On Fri, 2016-04-22 at 08:49 -0400, Coleen Phillimore wrote:
> This looks good.  Sorry, I thought I'd fixed this but apparently not 
> correctly.
> I'll sponsor it.

Thanks for the review, Coleen!

HG exported changeset is here for your convenience:
http://cr.openjdk.java.net/~sgehwolf/webrevs/JDK-8154210/JDK-8154210-Zero-better-byte-behaviour.jdk9.export.patch

Cheers,
Severin

> Coleen
> 
> 
> On 4/22/16 8:42 AM, Severin Gehwolf wrote:
> > 
> > Hi,
> > 
> > [new thread for JDK 9].
> > 
> > Could somebody please review this Zero-only fix for jdk9/dev? The April
> > CPU patches for OpenJDK broke this (bug 8132051). Please see the bug
> > for details.
> > 
> > The fixes are:
> > - Fix the jump table which is used for Zero release builds, since
> >    JDK-8132051 introduced a new bytecode _fast_zputfield.
> > - Make sure that results, which are a subword of a stack slot
> >    (possibly narrowed) are always at the lowest address.
> > 
> > The fix was originally written by Andrew Haley.
> > 
> > Bug: https://bugs.openjdk.java.net/browse/JDK-8154210
> > webrev: http://cr.openjdk.java.net/~sgehwolf/webrevs/JDK-8154210/webrev.02/
> > 
> > Once reviewed and pushed, we'd need a similar fix[2] for JDK 8u Zero
> > which is currently broken too. I think this fix needs to get pushed to
> > jdk9/dev directly since jdk9/hs does not have the CPU fixes yet.
> > 
> > Thoughts?
> > 
> > Thanks,
> > Severin
> > 
> > [1] http://cr.openjdk.java.net/~sgehwolf/webrevs/JDK-8154210/webrev.01/