libjava/include/java-interp.h

   1 // java-interp.h - Header file for the bytecode interpreter.  -*- c++ -*-
   2
   3 /* Copyright (C) 1999, 2000, 2001  Free Software Foundation
   4
   5    This file is part of libgcj.
   6
   7 This software is copyrighted work licensed under the terms of the
   8 Libgcj License.  Please consult the file "LIBGCJ_LICENSE" for
   9 details.  */
  10
  11 #ifndef __JAVA_INTERP_H__
  12 #define __JAVA_INTERP_H__
  13
  14 #include <jvm.h>
  15 #include <java-cpool.h>
  16
  17 #ifdef INTERPRETER
  18
  19 #pragma interface
  20
  21 #include <java/lang/Class.h>
  22 #include <java/lang/ClassLoader.h>
  23
  24 extern "C" {
  25 #include <ffi.h>
  26 }
  27
  28 extern inline jboolean
  29 _Jv_IsInterpretedClass (jclass c)
  30 {
  31   return (c->loader != 0);
  32 }
  33
  34 struct _Jv_ResolvedMethod;
  35
  36 bool _Jv_VerifyFieldSignature (_Jv_Utf8Const*sig);
  37 bool _Jv_VerifyMethodSignature (_Jv_Utf8Const*sig);
  38 bool _Jv_VerifyClassName (unsigned char* ptr, _Jv_ushort length);
  39 bool _Jv_VerifyClassName (_Jv_Utf8Const *name);
  40 bool _Jv_VerifyIdentifier (_Jv_Utf8Const *);
  41 bool _Jv_ClassNameSamePackage (_Jv_Utf8Const *name1, _Jv_Utf8Const *name2);
  42 void _Jv_DefineClass (jclass, jbyteArray, jint, jint);
  43
  44 void _Jv_InitField (jobject, jclass, int);
  45 void * _Jv_AllocMethodInvocation (jsize size);
  46 int  _Jv_count_arguments (_Jv_Utf8Const *signature,
  47                           jboolean staticp = true);
  48 void _Jv_VerifyMethod (_Jv_InterpMethod *method);
  49
  50 /* FIXME: this should really be defined in some more generic place */
  51 #define ROUND(V, A) (((((unsigned) (V))-1) | ((A)-1))+1)
  52
  53 /* the interpreter is written in C++, primarily because it makes it easy for
  54  * the entire thing to be "friend" with class Class. */
  55
  56 class _Jv_InterpClass;
  57 class _Jv_InterpMethod;
  58 class _Jv_InterpMethodInvocation;
  59
  60 class _Jv_InterpException
  61 {
  62   int  start_pc;
  63   int  end_pc;
  64   int  handler_pc;
  65   int  handler_type;
  66
  67   friend class _Jv_ClassReader;
  68   friend class _Jv_InterpMethod;
  69   friend class _Jv_BytecodeVerifier;
  70 };
  71
  72 // Base class for method representations.  Subclasses are interpreted
  73 // and JNI methods.
  74 class _Jv_MethodBase
  75 {
  76 protected:
  77   // The class which defined this method.
  78   _Jv_InterpClass *defining_class;
  79
  80   // The method description.
  81   _Jv_Method *self;
  82
  83   // Size of raw arguments.
  84   _Jv_ushort args_raw_size;
  85
  86 public:
  87   _Jv_Method *get_method ()
  88   {
  89     return self;
  90   }
  91 };
  92
  93 class _Jv_InterpMethod : public _Jv_MethodBase
  94 {
  95   _Jv_ushort       max_stack;
  96   _Jv_ushort       max_locals;
  97   int              code_length;
  98
  99   _Jv_ushort       exc_count;
 100
 101   unsigned char* bytecode ()
 102   {
 103     return
 104       ((unsigned char*)this)
 105       + ROUND((sizeof (_Jv_InterpMethod)
 106                + exc_count*sizeof (_Jv_InterpException)), 4);
 107   }
 108
 109   _Jv_InterpException * exceptions ()
 110   {
 111     return (_Jv_InterpException*) (this+1);
 112   }
 113
 114   static size_t size (int exc_count, int code_length)
 115   {
 116     return
 117       ROUND ((sizeof (_Jv_InterpMethod)
 118               + (exc_count * sizeof (_Jv_InterpException))), 4)
 119       + code_length;
 120   }
 121
 122   // return the method's invocation pointer (a stub).
 123   void *ncode ();
 124   void continue1 (_Jv_InterpMethodInvocation *inv);
 125
 126   static void run_normal (ffi_cif*, void*, ffi_raw*, void*);
 127   static void run_synch_object (ffi_cif*, void*, ffi_raw*, void*);
 128   static void run_synch_class (ffi_cif*, void*, ffi_raw*, void*);
 129
 130   inline jobject run (ffi_cif*, void*, ffi_raw*,
 131                       _Jv_InterpMethodInvocation*);
 132
 133   bool find_exception (jobject ex,
 134                        _Jv_InterpMethodInvocation *inv);
 135
 136  public:
 137   static void dump_object(jobject o);
 138
 139   friend class _Jv_ClassReader;
 140   friend class _Jv_InterpMethodInvocation;
 141   friend class _Jv_BytecodeVerifier;
 142
 143   friend void _Jv_PrepareClass(jclass);
 144 };
 145
 146 class _Jv_InterpMethodInvocation {
 147   _Jv_InterpMethod *running;
 148   _Jv_word         *sp;
 149   unsigned char    *pc;
 150   _Jv_word          state[0];
 151
 152   _Jv_word*         stack_base () { return &state[0]; }
 153   _Jv_word*         local_base () { return &state[running->max_stack]; }
 154
 155   friend class _Jv_InterpMethod;
 156 };
 157
 158 class _Jv_InterpClass : public java::lang::Class
 159 {
 160   _Jv_MethodBase **interpreted_methods;
 161   _Jv_ushort        *field_initializers;
 162
 163   friend class _Jv_ClassReader;
 164   friend class _Jv_InterpMethod;
 165   friend void  _Jv_PrepareClass(jclass);
 166   friend void  _Jv_InitField (jobject, jclass, int);
 167 #ifdef JV_MARKOBJ_DECL
 168   friend JV_MARKOBJ_DECL;
 169 #endif
 170
 171   friend _Jv_MethodBase ** _Jv_GetFirstMethod (_Jv_InterpClass *klass);
 172 };
 173
 174 extern inline _Jv_MethodBase **
 175 _Jv_GetFirstMethod (_Jv_InterpClass *klass)
 176 {
 177   return klass->interpreted_methods;
 178 }
 179
 180 struct _Jv_ResolvedMethod {
 181   jint            stack_item_count;
 182   jint            vtable_index;
 183   jclass          klass;
 184   _Jv_Method*     method;
 185
 186   // a resolved method holds the cif in-line, so that _Jv_MarkObj just needs
 187   // to mark the resolved method to hold on to the cif.  Some memory could be
 188   // saved by keeping a cache of cif's, since many will be the same.
 189   ffi_cif         cif;
 190   ffi_type *      arg_types[0];
 191 };
 192
 193 class _Jv_JNIMethod : public _Jv_MethodBase
 194 {
 195   // The underlying function.  If NULL we have to look for the
 196   // function.
 197   void *function;
 198
 199   // This is the CIF used by the JNI function.
 200   ffi_cif jni_cif;
 201
 202   // These are the argument types used by the JNI function.
 203   ffi_type **jni_arg_types;
 204
 205   // This function is used when making a JNI call from the interpreter.
 206   static void call (ffi_cif *, void *, ffi_raw *, void *);
 207
 208   void *ncode ();
 209
 210   friend class _Jv_ClassReader;
 211   friend void _Jv_PrepareClass(jclass);
 212
 213 public:
 214   // FIXME: this is ugly.
 215   void set_function (void *f)
 216   {
 217     function = f;
 218   }
 219 };
 220
 221 #endif /* INTERPRETER */
 222
 223 #endif /* __JAVA_INTERP_H__ */