review for 7052219: JSR 292: Crash in ~BufferBlob::MethodHandles adapters

[Vladimir Kozlov]

Looks good to me.

Vladimir

Tom Rodriguez wrote:
> http://cr.openjdk.java.net/~never/7052219
> 136 lines changed: 79 ins; 31 del; 26 mod; 14582 unchg
> 
> 7052219: JSR 292: Crash in ~BufferBlob::MethodHandles adapters
> Summary:
> Reviewed-by:
> 
> There were a set of bugs on both the JDK and VM side when dealing with
> rotation of arguments that could cause argument shearing which
> resulted in a large class of failures.  The mostly obvious ones were
> crashes from corrupted oops but it caused failures in other
> computations.  The primary bug was inconsistent rules for how the
> rotate was specified when writing over a double word value but there
> were also issues with how the source size was accounted for.  The main
> assembly had to be slightly adjusted to take this into account.
> Equivalent adjustments in the MethodHandleWalk were needed as well.  I
> also included a minor fix to skip unneeded interface checkcasts.  The
> verify logic was adjust to correctly complain about all these cases
> and there were some minor printing changes needed for debugging.
> 
> Tested on x86 and sparc 32/64 with the regression tests and vm.mlvm in
> both product and fastdebug.  All regression tests ran cleanly and the
> vm.mlwm tests are as clean as expected.  All the product crashes we'd
> been seeing before are fixed, though there's still some undiagnosed
> issue on sparc that results in occasional crashes in one of the stress
> tests.
>