review (S) for 6958485: fix for 6879921 was insufficient

[Volker Simonis]

Hi Tom,

I was just wondering how the testcase should fail. I tried with
1.7.0-ea-b96 (hs 19.0-b02) on Linux_amd64 and 1.6.0_20-b02 (hs
16.3-b01) on Solaris_sparc (both 32 and 64 bit) without problems. Is
the test specific to hs17 or does it not always fail?

Regards,
Volker

On Fri, Jun 4, 2010 at 7:18 PM, Tom Rodriguez <tom.rodriguez at oracle.com> wrote:
> http://cr.openjdk.java.net/~never/6958485
>
> 6958485: fix for 6879921 was insufficient
> Reviewed-by:
>
> 6879921 fixed a case where the superword optimization was attempting
> to handle arrays of oops which we shouldn't allow.  A guard was
> inserted in stmts_can_pack which fixed the original issue.  Testing
> with bigapps has shown that there are other paths where this problem
> can manifest.  In particular this pattern:
>
>  dst[i] = (src[i] != null ? false : true);
>
> shows that are_adjacent_refs can be reached through est_savings,
> skipping the added is_java_primitive guard.  The fix is to put an
> is_java_primitive guard into are_adjacent_refs to guard the data_size
> calls.  Tested with new testcase.
>