// java-interp.h - Header file for the bytecode interpreter.  -*- c++ -*-

/* Copyright (C) 1999  Red Hat, Inc.

   This file is part of libgcj.

This software is copyrighted work licensed under the terms of the
Libgcj License.  Please consult the file "LIBGCJ_LICENSE" for
details.  */

#ifndef __JAVA_INTERP_H__
#define __JAVA_INTERP_H__

#include <jvm.h>
#include <java-cpool.h>

#ifdef INTERPRETER

#pragma interface

#include <java/lang/Class.h>
#include <java/lang/ClassLoader.h>
#include <gnu/gcj/runtime/MethodInvocation.h>

extern "C" {
#include <ffi.h>
}

extern inline jboolean
_Jv_IsInterpretedClass (jclass c)
{
  return (c->loader != 0);
}

struct _Jv_ResolvedMethod;

void _Jv_VerifyFieldSignature (_Jv_Utf8Const*sig);
void _Jv_VerifyMethodSignature (_Jv_Utf8Const*sig);
void _Jv_VerifyClassName (unsigned char* ptr, _Jv_ushort length);
void _Jv_VerifyClassName (_Jv_Utf8Const *name);
void _Jv_VerifyIdentifier (_Jv_Utf8Const *);
bool _Jv_ClassNameSamePackage (_Jv_Utf8Const *name1, _Jv_Utf8Const *name2);
void _Jv_DefineClass (jclass, jbyteArray, jint, jint);
void _Jv_ResolveField (_Jv_Field *, java::lang::ClassLoader*);

void _Jv_InitField (jobject, jclass, int);
void * _Jv_AllocMethodInvocation (jsize size);

/* FIXME: this should really be defined in some more generic place */
#define ROUND(V, A) (((((unsigned) (V))-1) | ((A)-1))+1)

/* the interpreter is written in C++, primarily because it makes it easy for
 * the entire thing to be "friend" with class Class. */

class _Jv_InterpClass;
class _Jv_InterpMethod;
class _Jv_InterpMethodInvocation;

class _Jv_InterpException {
  int  start_pc;
  int  end_pc;
  int  handler_pc;
  int  handler_type;

  friend class _Jv_ClassReader;
  friend class _Jv_InterpMethod;
};

class _Jv_InterpMethod {

  _Jv_ushort       max_stack;
  _Jv_ushort       max_locals;
  int              code_length;

  _Jv_ushort       exc_count;
  _Jv_ushort       args_raw_size;

  _Jv_InterpClass *defining_class;
  _Jv_Method      *self;

  unsigned char* bytecode () 
  {
    return 
      ((unsigned char*)this) 
      + ROUND((sizeof (_Jv_InterpMethod)
	       + exc_count*sizeof (_Jv_InterpException)), 4);
  }
    
  _Jv_InterpException * exceptions ()
  {
    return (_Jv_InterpException*) (this+1);
  }

  static size_t size (int exc_count, int code_length)
  {
    return 
      ROUND ((sizeof (_Jv_InterpMethod) 
	      + (exc_count * sizeof (_Jv_InterpException))), 4)
      + code_length;
  }

  // return the method's invocation pointer (a stub).
  void *ncode ();
  void continue1 (_Jv_InterpMethodInvocation *inv);

  static void run_normal (ffi_cif*, void*, ffi_raw*, void*);
  static void run_synch_object (ffi_cif*, void*, ffi_raw*, void*);
  static void run_synch_class (ffi_cif*, void*, ffi_raw*, void*);

  inline jobject run (ffi_cif*, void*, ffi_raw*, 
		      _Jv_InterpMethodInvocation*);

  bool find_exception (jobject ex,
		       _Jv_InterpMethodInvocation *inv);

 public:
  static void dump_object(jobject o);

  friend class _Jv_ClassReader;
  friend class _Jv_InterpMethodInvocation;
  friend class gnu::gcj::runtime::MethodInvocation;

  friend void _Jv_PrepareClass(jclass);
};

class _Jv_InterpMethodInvocation {
  _Jv_InterpMethod *running;
  _Jv_word         *sp;
  unsigned char    *pc;
  _Jv_word          state[0];

  _Jv_word*         stack_base () { return &state[0]; }
  _Jv_word*         local_base () { return &state[running->max_stack]; }

  friend class _Jv_InterpMethod;
};
  
class _Jv_InterpClass : public java::lang::Class
{
  _Jv_InterpMethod **interpreted_methods;
  _Jv_ushort        *field_initializers;

  friend class _Jv_ClassReader;
  friend class _Jv_InterpMethod;
  friend void  _Jv_PrepareClass(jclass);
  friend void  _Jv_InitField (jobject, jclass, int);
  friend void* _Jv_MarkObj (void *, void *, void *, void *);
};

struct _Jv_ResolvedMethod {
  jint            stack_item_count;	
  jint            vtable_index;	
  jclass          klass;
  _Jv_Method*     method;

  // a resolved method holds the cif in-line, so that _Jv_MarkObj just needs
  // to mark the resolved method to hold on to the cif.  Some memory could be
  // saved by keeping a cache of cif's, since many will be the same.
  ffi_cif         cif;
  ffi_type *      arg_types[0];
};

#endif /* INTERPRETER */

#endif /* __JAVA_INTERP_H__ */