libjava/include/java-interp.h

   1 // java-interp.h - Header file for the bytecode interpreter.  -*- c++ -*-
   2
   3 /* Copyright (C) 1999, 2000, 2001, 2002  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 #include <gnu/gcj/runtime/NameFinder.h>
  17
  18 #ifdef INTERPRETER
  19
  20 #pragma interface
  21
  22 #include <java/lang/Class.h>
  23 #include <java/lang/ClassLoader.h>
  24 #include <gnu/gcj/runtime/StackTrace.h>
  25
  26 extern "C" {
  27 #include <ffi.h>
  28 }
  29
  30 extern inline jboolean
  31 _Jv_IsInterpretedClass (jclass c)
  32 {
  33   return (c->loader != 0);
  34 }
  35
  36 struct _Jv_ResolvedMethod;
  37
  38 void _Jv_DefineClass (jclass, jbyteArray, jint, jint);
  39
  40 void _Jv_InitField (jobject, jclass, int);
  41 void * _Jv_AllocMethodInvocation (jsize size);
  42 int  _Jv_count_arguments (_Jv_Utf8Const *signature,
  43                           jboolean staticp = true);
  44 void _Jv_VerifyMethod (_Jv_InterpMethod *method);
  45
  46 /* FIXME: this should really be defined in some more generic place */
  47 #define ROUND(V, A) (((((unsigned) (V))-1) | ((A)-1))+1)
  48
  49 /* the interpreter is written in C++, primarily because it makes it easy for
  50  * the entire thing to be "friend" with class Class. */
  51
  52 class _Jv_InterpClass;
  53 class _Jv_InterpMethod;
  54
  55 // Before a method is "compiled" we store values as the bytecode PC,
  56 // an int.  Afterwards we store them as pointers into the prepared
  57 // code itself.
  58 union _Jv_InterpPC
  59 {
  60   int i;
  61   void *p;
  62 };
  63
  64 class _Jv_InterpException
  65 {
  66   _Jv_InterpPC start_pc;
  67   _Jv_InterpPC end_pc;
  68   _Jv_InterpPC handler_pc;
  69   _Jv_InterpPC handler_type;
  70
  71   friend class _Jv_ClassReader;
  72   friend class _Jv_InterpMethod;
  73   friend class _Jv_BytecodeVerifier;
  74 };
  75
  76 // Base class for method representations.  Subclasses are interpreted
  77 // and JNI methods.
  78 class _Jv_MethodBase
  79 {
  80 protected:
  81   // The class which defined this method.
  82   _Jv_InterpClass *defining_class;
  83
  84   // The method description.
  85   _Jv_Method *self;
  86
  87   // Size of raw arguments.
  88   _Jv_ushort args_raw_size;
  89
  90 public:
  91   _Jv_Method *get_method ()
  92   {
  93     return self;
  94   }
  95 };
  96
  97 class _Jv_InterpMethod : public _Jv_MethodBase
  98 {
  99   _Jv_ushort       max_stack;
 100   _Jv_ushort       max_locals;
 101   int              code_length;
 102
 103   _Jv_ushort       exc_count;
 104
 105   void *prepared;
 106
 107   unsigned char* bytecode ()
 108   {
 109     return
 110       ((unsigned char*)this)
 111       + ROUND((sizeof (_Jv_InterpMethod)
 112                + exc_count*sizeof (_Jv_InterpException)), 4);
 113   }
 114
 115   _Jv_InterpException * exceptions ()
 116   {
 117     return (_Jv_InterpException*) (this+1);
 118   }
 119
 120   static size_t size (int exc_count, int code_length)
 121   {
 122     return
 123       ROUND ((sizeof (_Jv_InterpMethod)
 124               + (exc_count * sizeof (_Jv_InterpException))), 4)
 125       + code_length;
 126   }
 127
 128   // return the method's invocation pointer (a stub).
 129   void *ncode ();
 130   void compile (const void * const *);
 131
 132   static void run_normal (ffi_cif*, void*, ffi_raw*, void*);
 133   static void run_synch_object (ffi_cif*, void*, ffi_raw*, void*);
 134   static void run_synch_class (ffi_cif*, void*, ffi_raw*, void*);
 135
 136   void run (void*, ffi_raw *);
 137
 138  public:
 139   static void dump_object(jobject o);
 140
 141   friend class _Jv_ClassReader;
 142   friend class _Jv_BytecodeVerifier;
 143   friend class gnu::gcj::runtime::NameFinder;
 144   friend class gnu::gcj::runtime::StackTrace;
 145
 146   friend void _Jv_PrepareClass(jclass);
 147
 148 #ifdef JV_MARKOBJ_DECL
 149   friend JV_MARKOBJ_DECL;
 150 #endif
 151 };
 152
 153 class _Jv_InterpClass : public java::lang::Class
 154 {
 155   _Jv_MethodBase **interpreted_methods;
 156   _Jv_ushort        *field_initializers;
 157
 158   friend class _Jv_ClassReader;
 159   friend class _Jv_InterpMethod;
 160   friend void  _Jv_PrepareClass(jclass);
 161   friend void  _Jv_InitField (jobject, jclass, int);
 162 #ifdef JV_MARKOBJ_DECL
 163   friend JV_MARKOBJ_DECL;
 164 #endif
 165
 166   friend _Jv_MethodBase ** _Jv_GetFirstMethod (_Jv_InterpClass *klass);
 167 };
 168
 169 extern inline _Jv_MethodBase **
 170 _Jv_GetFirstMethod (_Jv_InterpClass *klass)
 171 {
 172   return klass->interpreted_methods;
 173 }
 174
 175 struct _Jv_ResolvedMethod {
 176   jint            stack_item_count;
 177   jint            vtable_index;
 178   jclass          klass;
 179   _Jv_Method*     method;
 180
 181   // a resolved method holds the cif in-line, so that _Jv_MarkObj just needs
 182   // to mark the resolved method to hold on to the cif.  Some memory could be
 183   // saved by keeping a cache of cif's, since many will be the same.
 184   ffi_cif         cif;
 185   ffi_type *      arg_types[0];
 186 };
 187
 188 class _Jv_JNIMethod : public _Jv_MethodBase
 189 {
 190   // The underlying function.  If NULL we have to look for the
 191   // function.
 192   void *function;
 193
 194   // This is the CIF used by the JNI function.
 195   ffi_cif jni_cif;
 196
 197   // These are the argument types used by the JNI function.
 198   ffi_type **jni_arg_types;
 199
 200   // This function is used when making a JNI call from the interpreter.
 201   static void call (ffi_cif *, void *, ffi_raw *, void *);
 202
 203   void *ncode ();
 204
 205   friend class _Jv_ClassReader;
 206   friend void _Jv_PrepareClass(jclass);
 207
 208 public:
 209   // FIXME: this is ugly.
 210   void set_function (void *f)
 211   {
 212     function = f;
 213   }
 214 };
 215
 216 // A structure of this type is used to link together interpreter
 217 // invocations on the stack.
 218 struct _Jv_MethodChain
 219 {
 220   const _Jv_InterpMethod *self;
 221   _Jv_MethodChain **ptr;
 222   _Jv_MethodChain *next;
 223
 224   _Jv_MethodChain (const _Jv_InterpMethod *s, _Jv_MethodChain **n)
 225   {
 226     self = s;
 227     ptr = n;
 228     next = *n;
 229     *n = this;
 230   }
 231
 232   ~_Jv_MethodChain ()
 233   {
 234     *ptr = next;
 235   }
 236 };
 237
 238 #endif /* INTERPRETER */
 239
 240 #endif /* __JAVA_INTERP_H__ */