toolchain/gcc/libjava/include/java-interp.h

   1 // java-interp.h - Header file for the bytecode interpreter.  -*- c++ -*-
   2
   3 /* Copyright (C) 1999, 2000, 2001, 2002, 2003  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 <java/lang/reflect/Modifier.h>
  25 #include <gnu/gcj/runtime/StackTrace.h>
  26
  27 extern "C" {
  28 #include <ffi.h>
  29 }
  30
  31 extern inline jboolean
  32 _Jv_IsInterpretedClass (jclass c)
  33 {
  34   return (c->accflags & java::lang::reflect::Modifier::INTERPRETED) != 0;
  35 }
  36
  37 struct _Jv_ResolvedMethod;
  38
  39 void _Jv_InitInterpreter ();
  40 void _Jv_DefineClass (jclass, jbyteArray, jint, jint);
  41
  42 void _Jv_InitField (jobject, jclass, int);
  43 void * _Jv_AllocMethodInvocation (jsize size);
  44 int  _Jv_count_arguments (_Jv_Utf8Const *signature,
  45                           jboolean staticp = true);
  46 void _Jv_VerifyMethod (_Jv_InterpMethod *method);
  47
  48 /* FIXME: this should really be defined in some more generic place */
  49 #define ROUND(V, A) (((((unsigned) (V))-1) | ((A)-1))+1)
  50
  51 /* the interpreter is written in C++, primarily because it makes it easy for
  52  * the entire thing to be "friend" with class Class. */
  53
  54 class _Jv_InterpClass;
  55 class _Jv_InterpMethod;
  56
  57 // Before a method is "compiled" we store values as the bytecode PC,
  58 // an int.  Afterwards we store them as pointers into the prepared
  59 // code itself.
  60 union _Jv_InterpPC
  61 {
  62   int i;
  63   void *p;
  64 };
  65
  66 class _Jv_InterpException
  67 {
  68   _Jv_InterpPC start_pc;
  69   _Jv_InterpPC end_pc;
  70   _Jv_InterpPC handler_pc;
  71   _Jv_InterpPC handler_type;
  72
  73   friend class _Jv_ClassReader;
  74   friend class _Jv_InterpMethod;
  75   friend class _Jv_BytecodeVerifier;
  76 };
  77
  78 // Base class for method representations.  Subclasses are interpreted
  79 // and JNI methods.
  80 class _Jv_MethodBase
  81 {
  82 protected:
  83   // The class which defined this method.
  84   _Jv_InterpClass *defining_class;
  85
  86   // The method description.
  87   _Jv_Method *self;
  88
  89   // Size of raw arguments.
  90   _Jv_ushort args_raw_size;
  91
  92   // Chain of addresses to fill in.  See _Jv_Defer_Resolution.
  93   void *deferred;
  94
  95   friend void _Jv_Defer_Resolution (void *cl, _Jv_Method *meth, void **);
  96   friend void _Jv_PrepareClass(jclass);
  97
  98 public:
  99   _Jv_Method *get_method ()
 100   {
 101     return self;
 102   }
 103 };
 104
 105 class _Jv_InterpMethod : public _Jv_MethodBase
 106 {
 107   _Jv_ushort       max_stack;
 108   _Jv_ushort       max_locals;
 109   int              code_length;
 110
 111   _Jv_ushort       exc_count;
 112
 113   void *prepared;
 114
 115   unsigned char* bytecode ()
 116   {
 117     return
 118       ((unsigned char*)this)
 119       + ROUND((sizeof (_Jv_InterpMethod)
 120                + exc_count*sizeof (_Jv_InterpException)), 4);
 121   }
 122
 123   _Jv_InterpException * exceptions ()
 124   {
 125     return (_Jv_InterpException*) (this+1);
 126   }
 127
 128   static size_t size (int exc_count, int code_length)
 129   {
 130     return
 131       ROUND ((sizeof (_Jv_InterpMethod)
 132               + (exc_count * sizeof (_Jv_InterpException))), 4)
 133       + code_length;
 134   }
 135
 136   // return the method's invocation pointer (a stub).
 137   void *ncode ();
 138   void compile (const void * const *);
 139
 140   static void run_normal (ffi_cif*, void*, ffi_raw*, void*);
 141   static void run_synch_object (ffi_cif*, void*, ffi_raw*, void*);
 142   static void run_class (ffi_cif*, void*, ffi_raw*, void*);
 143   static void run_synch_class (ffi_cif*, void*, ffi_raw*, void*);
 144
 145   void run (void*, ffi_raw *);
 146
 147  public:
 148   static void dump_object(jobject o);
 149
 150   friend class _Jv_ClassReader;
 151   friend class _Jv_BytecodeVerifier;
 152   friend class gnu::gcj::runtime::NameFinder;
 153   friend class gnu::gcj::runtime::StackTrace;
 154
 155   friend void _Jv_PrepareClass(jclass);
 156
 157 #ifdef JV_MARKOBJ_DECL
 158   friend JV_MARKOBJ_DECL;
 159 #endif
 160 };
 161
 162 class _Jv_InterpClass : public java::lang::Class
 163 {
 164   _Jv_MethodBase **interpreted_methods;
 165   _Jv_ushort        *field_initializers;
 166
 167   friend class _Jv_ClassReader;
 168   friend class _Jv_InterpMethod;
 169   friend void  _Jv_PrepareClass(jclass);
 170   friend void  _Jv_PrepareMissingMethods (jclass base2, jclass iface_class);
 171   friend void  _Jv_InitField (jobject, jclass, int);
 172 #ifdef JV_MARKOBJ_DECL
 173   friend JV_MARKOBJ_DECL;
 174 #endif
 175
 176   friend _Jv_MethodBase ** _Jv_GetFirstMethod (_Jv_InterpClass *klass);
 177   friend void _Jv_Defer_Resolution (void *cl, _Jv_Method *meth, void **);
 178 };
 179
 180 // We have an interpreted class CL and we're trying to find the
 181 // address of the ncode of a method METH.  That interpreted class
 182 // hasn't yet been prepared, so we defer fixups until they are ready.
 183 // To do this, we create a chain of fixups that will be resolved by
 184 // _Jv_PrepareClass.
 185 extern inline void
 186 _Jv_Defer_Resolution (void *cl, _Jv_Method *meth, void **address)
 187 {
 188   int i;
 189   _Jv_InterpClass *self = (_Jv_InterpClass *)cl;
 190   for (i = 0; i < self->method_count; i++)
 191     {
 192       _Jv_Method *m = &self->methods[i];
 193       if (m == meth)
 194         {
 195           _Jv_MethodBase *imeth = self->interpreted_methods[i];
 196           *address = imeth->deferred;
 197           imeth->deferred = address;
 198           return;
 199         }
 200     }
 201   return;
 202 }
 203
 204 extern inline _Jv_MethodBase **
 205 _Jv_GetFirstMethod (_Jv_InterpClass *klass)
 206 {
 207   return klass->interpreted_methods;
 208 }
 209
 210 struct _Jv_ResolvedMethod {
 211   jint            stack_item_count;
 212   jint            vtable_index;
 213   jclass          klass;
 214   _Jv_Method*     method;
 215
 216   // a resolved method holds the cif in-line, so that _Jv_MarkObj just needs
 217   // to mark the resolved method to hold on to the cif.  Some memory could be
 218   // saved by keeping a cache of cif's, since many will be the same.
 219   ffi_cif         cif;
 220   ffi_type *      arg_types[0];
 221 };
 222
 223 class _Jv_JNIMethod : public _Jv_MethodBase
 224 {
 225   // The underlying function.  If NULL we have to look for the
 226   // function.
 227   void *function;
 228
 229   // This is the CIF used by the JNI function.
 230   ffi_cif jni_cif;
 231
 232   // These are the argument types used by the JNI function.
 233   ffi_type **jni_arg_types;
 234
 235   // This function is used when making a JNI call from the interpreter.
 236   static void call (ffi_cif *, void *, ffi_raw *, void *);
 237
 238   void *ncode ();
 239
 240   friend class _Jv_ClassReader;
 241   friend void _Jv_PrepareClass(jclass);
 242
 243 public:
 244   // FIXME: this is ugly.
 245   void set_function (void *f)
 246   {
 247     function = f;
 248   }
 249 };
 250
 251 // A structure of this type is used to link together interpreter
 252 // invocations on the stack.
 253 struct _Jv_MethodChain
 254 {
 255   const _Jv_InterpMethod *self;
 256   _Jv_MethodChain **ptr;
 257   _Jv_MethodChain *next;
 258
 259   _Jv_MethodChain (const _Jv_InterpMethod *s, _Jv_MethodChain **n)
 260   {
 261     self = s;
 262     ptr = n;
 263     next = *n;
 264     *n = this;
 265   }
 266
 267   ~_Jv_MethodChain ()
 268   {
 269     *ptr = next;
 270   }
 271 };
 272
 273 #endif /* INTERPRETER */
 274
 275 #endif /* __JAVA_INTERP_H__ */