preliminary review (L): 6939861: JVM should handle more conversion operations

[Christian Thalinger]

On Sep 10, 2010, at 10:47 AM, John Rose wrote:
> This is the JVM infrastructure for pushing a stack frame *during* a  
> method handle call, so that some sort of intermediate fixup  
> operation can be done before completing the call.
>
> The requirement is that a recognizable stack frame be pushed during  
> the intermediate fixup operation, so that if there is an exception,  
> or a GC, or some other stack walk, the stack will be parsed  
> properly.  Crucially, the pending arguments must be recognized as  
> managed pointers.
>
> This is a preliminary review, because it shows just the new stack  
> frame type, rather than the use cases (which are forthcoming).
>
> 6939861: JVM should handle more conversion operations
> http://cr.openjdk.java.net/~jrose/6939861/webrev.00/


src/share/vm/code/codeBlob.cpp:

Have you tried to apply this change to a current HotSpot version?   
CodeBlob does not have instructions_begin/end anymore but  
content_begin/end or code_begin/end, depends on what you really want.


src/share/vm/prims/methodHandles.hpp:

+  enum {                        // arg_mask values, used only for  
TaggedStackInterpreter

I removed tagged stack interpreter support as of 6943304.


Can we move enum method_handles_platform_dependent_constants from  
stubRoutines_<arch_model>.hpp to methodHandles_<arch>.hpp in this  
change?

I also looked at the methodHandles_x86.cpp changes but it's hard to  
tell if everything is correct.

-- Christian