[8u] RFR: 8233023: assert(Opcode() == mem->Opcode() || phase->C->get_alias_index(adr_type()) == Compile::AliasIdxRaw) failed: no mismatched stores, except on raw memory

[Andrew John Hughes]

On 30/10/2019 09:41, Severin Gehwolf wrote:
> Hi,
> 
> Could I please get a review of this 8u only issue? The reason a
> fastdebug build of latest OpenJDK 8u asserts for the dec-tree benchmark
> of the renaissance suite is because the 8u backport of JDK-8140309 was
> missing this hunk from JDK 9[1]:
> 
> +             (Opcode() == Op_StoreL && st->Opcode() == Op_StoreI) || // expanded ClearArrayNode
> +             (is_mismatched_access() || st->as_Store()->is_mismatched_access()),
> 
> I had a closer look and there doesn't seem to be missing anything else.
> The proposed fix is to amend the assert condition in the appropriate
> place, which brings 8u in line with JDK 9 code where the failure isn't
> observed.
> 
> Bug: https://bugs.openjdk.java.net/browse/JDK-8233023
> webrev: http://cr.openjdk.java.net/~sgehwolf/webrevs/JDK-8233023/01/webrev/
> 
> Testing: 8u tier1 test set with fastdebug build on x86_64 Linux. No new
> failures. dec-tree benchmark now runs successfully on an 8u fastdebug
> build.
> 
> Thoughts?
> 
> Thanks,
> Severin
> 
> [1] http://hg.openjdk.java.net/jdk9/jdk9/hotspot/rev/4bee38ba018c
> 

I compared the two patches and this missing hunk does stand out. So the
patch looks fine in that respect.

I notice they also didn't backport the testcase to 8u. Any thoughts on
including that?

Thanks,
-- 
Andrew :)

Senior Free Java Software Engineer
Red Hat, Inc. (http://www.redhat.com)

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