JVM Interpreter

[Kim Barrett]

> On Aug 25, 2018, at 2:39 PM, mr rupplin <mearvk at outlook.com> wrote:
> 
> I am presuming the JVM interpreter is defined/implemented in the the hotspot module since this is a JVM implementation.

This is probably more of a hotspot-dev or hotspot-runtime-dev kind of question, rather than core-libs.

> I cannot seem to find *any* instruction in it that gets called by a simple "./java -ea Class" call.  We are stumped.
> 
> 
> For instance there are methods for local set and reference:
> 
> 
> void BytecodeInterpreter::set_stack_slot(intptr_t *tos, address value, int offset) {
> 
>    *((address *)&tos[Interpreter::expr_index_at(-offset)]) = value;
> }
> 
> void BytecodeInterpreter::set_stack_object(intptr_t *tos, oop value, int offset) {
> 
>  *((oop *)&tos[Interpreter::expr_index_at(-offset)]) = value;
> }
> 
> These (and similar in same file) are not being called at all during the JVM interpreter phase (simple java program as reference).  My program creates an object and calls a test method with a single object as reference.
> 
> What could be the hang up?  No printf statement seems to work.

I think BytecodeInterpreter is part of CppInterpreter, which I think
is only used by Zero platforms, with the TemplateInterpreter used by
all other platforms.  So unless you are running on a platform that
uses Zero, or specifically built for Zero, I think BytecodeInterpreter
won't be used (and might not even be compiled in?).

> Thanks.
> 
> Max Rupplin
> 
> Software Engineer