Lost perf between 8u40 and 9 hs-comp

[Vladimir Ivanov]

>> Right now, VM doesn't care about profiling logic at all. The intrinsic
>> is used only to inject profile data and all profiling happens in Java
>> code. Once MHI.profileBoolean is intrinsified (profile is injected),
>> no profiling actions are performed.
>
> What I'm thinking is that an uncommon trap could re-run the interpreter
> definition of MHI.profileBoolean using Action_reinterpret.
> That would update the state, wouldn't it?  Then the compiler would
> recompile (after a little time) and see the updated state.
Just setting reexecute=true isn't enough - MHI.profileBoolean is located 
earlier in bytecode, but only last instruction will be reexecuted.

Here's an excerpt from GWT bytecode:
...
   invokevirtual MH.invokeBasic:(...)I
   invokestatic  MHI.profileBoolean:(Z[I)Z  <== profiling
   istore        n
...
   iload         n
   iconst_1
   iand
   ifeq          m                          <== trap happens here
...

In general, there could be other actions between ifeq & 
MHI.profileBoolean, so it's not possible to restore state and reexecute 
the code starting from MHI.profileBoolean.

Am I missing something?

Best regards,
Vladimir Ivanov