[11] RFR(S): 8148871: Possible wrong expression stack depth at deopt point

[Tom Rodriguez]

Looks good.  Thanks for diagnosing this.

tom

Tobias Hartmann wrote:
> Hi,
>
> please review the following patch:
> https://bugs.openjdk.java.net/browse/JDK-8148871
> http://cr.openjdk.java.net/~thartmann/8148871/webrev.00/
>
> The problem is that the stack verification code uses the interpreter oop map to get the stack size
> of the next instruction. However, for calls, the oop map contains the state *after* the instruction.
> With next_mask_expression_stack_size = 0, the result of 'next_mask_expression_stack_size -
> top_frame_expression_stack_adjustment' is negative and verification fails. For details, see my
> comment in the bug [1].
>
> The fix is to add a special case for invoke bytecodes and use the parameter size instead of the oop
> map in that case. Tested with hs-tier1/2 with -XX:+VerifyStack (I hit 8198826 which I'll fix with
> another patch).
>
> Thanks,
> Tobias
>
> [1]
> https://bugs.openjdk.java.net/browse/JDK-8148871?focusedCommentId=14160003&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-14160003