checkSnippetKills

[Bernhard Urban]

Hi Tom,

thanks, there's indeed a problem around SnippetCounters. First, as a
comment in the snippet counter implementation already suggest, it should
not use ANY_LOCATION but a separate location designated to snippet
counters.  After doing that, it exposes another problem around HotSpot
stubs.  Stubs are not allowed to embed oops in their code.  Thus my fix
excludes snippet counters in snippets designed for stubs.

Apparently we don't use snippet counters that much lately ;-) I'm pushing
it through the gate now, in the meanwhile you can fetch the patch from
here: http://lafo.ssw.uni-linz.ac.at/lewurm/snippetcounters.patch

-Bernhard


On Wed, Mar 26, 2014 at 8:36 PM, Deneau, Tom <tom.deneau at amd.com> wrote:

> I just tried this with the amd64 backend and got similar results
> I compiled:
>     MyObj[] escapingObject;
>
>     public void newObjTest(int gid) {
>         escapingObject[gid] = new MyObj();
>     }
>
> and using -G:+SnippetCounters
>
> The log showed
>
>                 Lowering allocateInstance in
> StructuredGraph:18{HotSpotMethod<BasicTest2.newObjTest(int)>}:
> node=159|NewInstance,
> template=StructuredGraph:39{HotSpotMethod<NewObjectSnippets.allocateInstance(int,
> Word, Word, boolean, Register, boolean, String)>}(<constant> [0], long [1],
> <unused> [2], <constant> [3], <constant> [4], <constant> [5], <constant>
> [6]), arguments=Parameters<NewObjectSnippets.allocateInstance [const size =
> 16, hub = 124|Const(4296021216), prototypeMarkWord = 5, const fillContents
> = true, const threadRegister = r15, const constantSize = true, const
> typeContext = >
>                 WARNING: 159|NewInstance is not a MemoryCheckpoint, but
> the snippet graph contains kills ([ANY_LOCATION]). You might want
> 159|NewInstance to be a MemoryCheckpoint
>                   [thread:1] scope:
> BasicTest2.Compiling.GraalCompiler.FrontEnd.LowTier.Lowering.IncrementalCanonicalizer.LoweringIteration0.InterceptException
>                   Exception occurred in scope:
> BasicTest2.Compiling.GraalCompiler.FrontEnd.LowTier.Lowering.IncrementalCanonicalizer.LoweringIteration0.InterceptException
>                   Context obj java.lang.AssertionError: snippet graph
> contains a kill to ANY_LOCATION, but replacee (159|NewInstance) doesn't
> kill ANY_LOCATION.  kills: [ANY_LOCATION]
>
>
>
> > -----Original Message-----
> > From: Deneau, Tom
> > Sent: Wednesday, March 26, 2014 2:27 PM
> > To: graal-dev at openjdk.java.net
> > Subject: checkSnippetKills
> >
> > I have a snippet for NewInstance that works but I wanted to increment a
> > snippet counter on one of the paths thru the snippet.  After doing that
> > and using -G:+SnippetCounters, I get the following error:
> >
> > java.lang.AssertionError: snippet graph contains a kill to ANY_LOCATION,
> > but replacee (333|NewInstance) doesn't kill ANY_LOCATION.  kills:
> > [ANY_LOCATION, Initialization]
> >       at
> > com.oracle.graal.replacements.SnippetTemplate.checkSnippetKills(SnippetT
> > emplate.java:946)
> >
> > How should this be corrected?
> >
> > -- Tom
>
>