libjava/resolve.cc

   1 // resolve.cc - Code for linking and resolving classes and pool entries.
   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 /* Author: Kresten Krab Thorup <krab@gnu.org>  */
  12
  13 #include <config.h>
  14
  15 #include <java-interp.h>
  16
  17 #include <jvm.h>
  18 #include <gcj/cni.h>
  19 #include <string.h>
  20 #include <java-cpool.h>
  21 #include <java/lang/Class.h>
  22 #include <java/lang/String.h>
  23 #include <java/lang/StringBuffer.h>
  24 #include <java/lang/Thread.h>
  25 #include <java/lang/InternalError.h>
  26 #include <java/lang/VirtualMachineError.h>
  27 #include <java/lang/NoSuchFieldError.h>
  28 #include <java/lang/NoSuchMethodError.h>
  29 #include <java/lang/ClassFormatError.h>
  30 #include <java/lang/IllegalAccessError.h>
  31 #include <java/lang/AbstractMethodError.h>
  32 #include <java/lang/NoClassDefFoundError.h>
  33 #include <java/lang/IncompatibleClassChangeError.h>
  34 #include <java/lang/reflect/Modifier.h>
  35
  36 using namespace gcj;
  37
  38 void
  39 _Jv_ResolveField (_Jv_Field *field, java::lang::ClassLoader *loader)
  40 {
  41   if (! field->isResolved ())
  42     {
  43       _Jv_Utf8Const *sig = (_Jv_Utf8Const*)field->type;
  44       field->type = _Jv_FindClassFromSignature (sig->data, loader);
  45       field->flags &= ~_Jv_FIELD_UNRESOLVED_FLAG;
  46     }
  47 }
  48
  49 #ifdef INTERPRETER
  50
  51 static void throw_internal_error (char *msg)
  52         __attribute__ ((__noreturn__));
  53 static void throw_class_format_error (jstring msg)
  54         __attribute__ ((__noreturn__));
  55 static void throw_class_format_error (char *msg)
  56         __attribute__ ((__noreturn__));
  57
  58 static int get_alignment_from_class (jclass);
  59
  60 static _Jv_ResolvedMethod*
  61 _Jv_BuildResolvedMethod (_Jv_Method*,
  62                          jclass,
  63                          jboolean,
  64                          jint);
  65
  66
  67 static void throw_incompatible_class_change_error (jstring msg)
  68 {
  69   throw new java::lang::IncompatibleClassChangeError (msg);
  70 }
  71
  72 _Jv_word
  73 _Jv_ResolvePoolEntry (jclass klass, int index)
  74 {
  75   using namespace java::lang::reflect;
  76
  77   _Jv_Constants *pool = &klass->constants;
  78
  79   if ((pool->tags[index] & JV_CONSTANT_ResolvedFlag) != 0)
  80     return pool->data[index];
  81
  82   switch (pool->tags[index]) {
  83   case JV_CONSTANT_Class:
  84     {
  85       _Jv_Utf8Const *name = pool->data[index].utf8;
  86
  87       jclass found;
  88       if (name->data[0] == '[')
  89         found = _Jv_FindClassFromSignature (&name->data[0],
  90                                             klass->loader);
  91       else
  92         found = _Jv_FindClass (name, klass->loader);
  93
  94       if (! found)
  95         {
  96           jstring str = _Jv_NewStringUTF (name->data);
  97           // This exception is specified in JLS 2nd Ed, section 5.1.
  98           throw new java::lang::NoClassDefFoundError (str);
  99         }
 100
 101       if ((found->accflags & Modifier::PUBLIC) == Modifier::PUBLIC
 102           || (_Jv_ClassNameSamePackage (found->name,
 103                                         klass->name)))
 104         {
 105           pool->data[index].clazz = found;
 106           pool->tags[index] |= JV_CONSTANT_ResolvedFlag;
 107         }
 108       else
 109         {
 110           throw new java::lang::IllegalAccessError (found->getName());
 111         }
 112     }
 113     break;
 114
 115   case JV_CONSTANT_String:
 116     {
 117       jstring str;
 118       str = _Jv_NewStringUtf8Const (pool->data[index].utf8);
 119       pool->data[index].o = str;
 120       pool->tags[index] |= JV_CONSTANT_ResolvedFlag;
 121     }
 122     break;
 123
 124
 125   case JV_CONSTANT_Fieldref:
 126     {
 127       _Jv_ushort class_index, name_and_type_index;
 128       _Jv_loadIndexes (&pool->data[index],
 129                        class_index,
 130                        name_and_type_index);
 131       jclass owner = (_Jv_ResolvePoolEntry (klass, class_index)).clazz;
 132
 133       if (owner != klass)
 134         _Jv_InitClass (owner);
 135
 136       _Jv_ushort name_index, type_index;
 137       _Jv_loadIndexes (&pool->data[name_and_type_index],
 138                        name_index,
 139                        type_index);
 140
 141       _Jv_Utf8Const *field_name = pool->data[name_index].utf8;
 142       _Jv_Utf8Const *field_type_name = pool->data[type_index].utf8;
 143
 144       // FIXME: The implementation of this function
 145       // (_Jv_FindClassFromSignature) will generate an instance of
 146       // _Jv_Utf8Const for each call if the field type is a class name
 147       // (Lxx.yy.Z;).  This may be too expensive to do for each and
 148       // every fieldref being resolved.  For now, we fix the problem by
 149       // only doing it when we have a loader different from the class
 150       // declaring the field.
 151
 152       jclass field_type = 0;
 153
 154       if (owner->loader != klass->loader)
 155         field_type = _Jv_FindClassFromSignature (field_type_name->data,
 156                                                  klass->loader);
 157
 158       _Jv_Field* the_field = 0;
 159
 160       for (jclass cls = owner; cls != 0; cls = cls->getSuperclass ())
 161         {
 162           for (int i = 0;  i < cls->field_count;  i++)
 163             {
 164               _Jv_Field *field = &cls->fields[i];
 165               if (! _Jv_equalUtf8Consts (field->name, field_name))
 166                 continue;
 167
 168               // now, check field access.
 169
 170               if (   (cls == klass)
 171                   || ((field->flags & Modifier::PUBLIC) != 0)
 172                   || (((field->flags & Modifier::PROTECTED) != 0)
 173                       && cls->isAssignableFrom (klass))
 174                   || (((field->flags & Modifier::PRIVATE) == 0)
 175                       && _Jv_ClassNameSamePackage (cls->name,
 176                                                    klass->name)))
 177                 {
 178                   /* resove the field using the class' own loader
 179                      if necessary */
 180
 181                   if (!field->isResolved ())
 182                     _Jv_ResolveField (field, cls->loader);
 183
 184                   if (field_type != 0 && field->type != field_type)
 185                     throw new java::lang::LinkageError
 186                       (JvNewStringLatin1
 187                        ("field type mismatch with different loaders"));
 188
 189                   the_field = field;
 190                   goto end_of_field_search;
 191                 }
 192               else
 193                 {
 194                   throw new java::lang::IllegalAccessError;
 195                 }
 196             }
 197         }
 198
 199     end_of_field_search:
 200       if (the_field == 0)
 201         {
 202           java::lang::StringBuffer *sb = new java::lang::StringBuffer();
 203           sb->append(JvNewStringLatin1("field "));
 204           sb->append(owner->getName());
 205           sb->append(JvNewStringLatin1("."));
 206           sb->append(_Jv_NewStringUTF(field_name->data));
 207           sb->append(JvNewStringLatin1(" was not found."));
 208           throw_incompatible_class_change_error(sb->toString());
 209         }
 210
 211       pool->data[index].field = the_field;
 212       pool->tags[index] |= JV_CONSTANT_ResolvedFlag;
 213     }
 214     break;
 215
 216   case JV_CONSTANT_Methodref:
 217   case JV_CONSTANT_InterfaceMethodref:
 218     {
 219       _Jv_ushort class_index, name_and_type_index;
 220       _Jv_loadIndexes (&pool->data[index],
 221                        class_index,
 222                        name_and_type_index);
 223       jclass owner = (_Jv_ResolvePoolEntry (klass, class_index)).clazz;
 224
 225       if (owner != klass)
 226         _Jv_InitClass (owner);
 227
 228       _Jv_ushort name_index, type_index;
 229       _Jv_loadIndexes (&pool->data[name_and_type_index],
 230                        name_index,
 231                        type_index);
 232
 233       _Jv_Utf8Const *method_name = pool->data[name_index].utf8;
 234       _Jv_Utf8Const *method_signature = pool->data[type_index].utf8;
 235
 236       _Jv_Method *the_method = 0;
 237       jclass found_class = 0;
 238
 239       // First search the class itself.
 240       the_method = _Jv_SearchMethodInClass (owner, klass,
 241                                             method_name, method_signature);
 242
 243       if (the_method != 0)
 244         {
 245           found_class = owner;
 246           goto end_of_method_search;
 247         }
 248
 249       // If we are resolving an interface method, search the
 250       // interface's superinterfaces (A superinterface is not an
 251       // interface's superclass - a superinterface is implemented by
 252       // the interface).
 253       if (pool->tags[index] == JV_CONSTANT_InterfaceMethodref)
 254         {
 255           _Jv_ifaces ifaces;
 256           ifaces.count = 0;
 257           ifaces.len = 4;
 258           ifaces.list = (jclass *) _Jv_Malloc (ifaces.len * sizeof (jclass *));
 259
 260           _Jv_GetInterfaces (owner, &ifaces);
 261
 262           for (int i = 0; i < ifaces.count; i++)
 263             {
 264               jclass cls = ifaces.list[i];
 265               the_method = _Jv_SearchMethodInClass (cls, klass, method_name,
 266                                                     method_signature);
 267               if (the_method != 0)
 268                 {
 269                   found_class = cls;
 270                   break;
 271                 }
 272             }
 273
 274           _Jv_Free (ifaces.list);
 275
 276           if (the_method != 0)
 277             goto end_of_method_search;
 278         }
 279
 280       // Finally, search superclasses.
 281       for (jclass cls = owner->getSuperclass (); cls != 0;
 282            cls = cls->getSuperclass ())
 283         {
 284           the_method = _Jv_SearchMethodInClass (cls, klass,
 285                                                 method_name, method_signature);
 286           if (the_method != 0)
 287             {
 288               found_class = cls;
 289               break;
 290             }
 291         }
 292
 293     end_of_method_search:
 294
 295       // FIXME: if (cls->loader != klass->loader), then we
 296       // must actually check that the types of arguments
 297       // correspond.  That is, for each argument type, and
 298       // the return type, doing _Jv_FindClassFromSignature
 299       // with either loader should produce the same result,
 300       // i.e., exactly the same jclass object. JVMS 5.4.3.3
 301
 302       if (the_method == 0)
 303         {
 304           java::lang::StringBuffer *sb = new java::lang::StringBuffer();
 305           sb->append(JvNewStringLatin1("method "));
 306           sb->append(owner->getName());
 307           sb->append(JvNewStringLatin1("."));
 308           sb->append(_Jv_NewStringUTF(method_name->data));
 309           sb->append(JvNewStringLatin1(" was not found."));
 310           throw new java::lang::NoSuchMethodError (sb->toString());
 311         }
 312
 313       int vtable_index = -1;
 314       if (pool->tags[index] != JV_CONSTANT_InterfaceMethodref)
 315         vtable_index = (jshort)the_method->index;
 316
 317       pool->data[index].rmethod =
 318         _Jv_BuildResolvedMethod(the_method,
 319                                 found_class,
 320                                 (the_method->accflags & Modifier::STATIC) != 0,
 321                                 vtable_index);
 322       pool->tags[index] |= JV_CONSTANT_ResolvedFlag;
 323     }
 324     break;
 325
 326   }
 327
 328   return pool->data[index];
 329 }
 330
 331 // Find a method declared in the cls that is referenced from klass and
 332 // perform access checks.
 333 _Jv_Method *
 334 _Jv_SearchMethodInClass (jclass cls, jclass klass,
 335                          _Jv_Utf8Const *method_name,
 336                          _Jv_Utf8Const *method_signature)
 337 {
 338   using namespace java::lang::reflect;
 339
 340   for (int i = 0;  i < cls->method_count;  i++)
 341     {
 342       _Jv_Method *method = &cls->methods[i];
 343       if (   (!_Jv_equalUtf8Consts (method->name,
 344                                     method_name))
 345           || (!_Jv_equalUtf8Consts (method->signature,
 346                                     method_signature)))
 347         continue;
 348
 349       if (cls == klass
 350           || ((method->accflags & Modifier::PUBLIC) != 0)
 351           || (((method->accflags & Modifier::PROTECTED) != 0)
 352               && cls->isAssignableFrom (klass))
 353           || (((method->accflags & Modifier::PRIVATE) == 0)
 354               && _Jv_ClassNameSamePackage (cls->name,
 355                                            klass->name)))
 356         {
 357           return method;
 358         }
 359       else
 360         {
 361           throw new java::lang::IllegalAccessError;
 362         }
 363     }
 364   return 0;
 365 }
 366
 367 // A helper for _Jv_PrepareClass.  This adds missing `Miranda methods'
 368 // to a class.
 369 void
 370 _Jv_PrepareMissingMethods (jclass base2, jclass iface_class)
 371 {
 372   _Jv_InterpClass *base = reinterpret_cast<_Jv_InterpClass *> (base2);
 373   for (int i = 0; i < iface_class->interface_count; ++i)
 374     {
 375       for (int j = 0; j < iface_class->interfaces[i]->method_count; ++j)
 376         {
 377           _Jv_Method *meth = &iface_class->interfaces[i]->methods[j];
 378           // Don't bother with <clinit>.
 379           if (meth->name->data[0] == '<')
 380             continue;
 381           _Jv_Method *new_meth = _Jv_LookupDeclaredMethod (base, meth->name,
 382                                                            meth->signature);
 383           if (! new_meth)
 384             {
 385               // We assume that such methods are very unlikely, so we
 386               // just reallocate the method array each time one is
 387               // found.  This greatly simplifies the searching --
 388               // otherwise we have to make sure that each such method
 389               // found is really unique among all superinterfaces.
 390               int new_count = base->method_count + 1;
 391               _Jv_Method *new_m
 392                 = (_Jv_Method *) _Jv_AllocBytes (sizeof (_Jv_Method)
 393                                                  * new_count);
 394               memcpy (new_m, base->methods,
 395                       sizeof (_Jv_Method) * base->method_count);
 396
 397               // Add new method.
 398               new_m[base->method_count] = *meth;
 399               new_m[base->method_count].index = (_Jv_ushort) -1;
 400               new_m[base->method_count].accflags
 401                 |= java::lang::reflect::Modifier::INVISIBLE;
 402
 403               _Jv_MethodBase **new_im
 404                 = (_Jv_MethodBase **) _Jv_AllocBytes (sizeof (_Jv_MethodBase *)
 405                                                       * new_count);
 406               memcpy (new_im, base->interpreted_methods,
 407                       sizeof (_Jv_MethodBase *) * base->method_count);
 408
 409               base->methods = new_m;
 410               base->interpreted_methods = new_im;
 411               base->method_count = new_count;
 412             }
 413         }
 414
 415       _Jv_PrepareMissingMethods (base, iface_class->interfaces[i]);
 416     }
 417 }
 418
 419 void
 420 _Jv_PrepareClass(jclass klass)
 421 {
 422   using namespace java::lang::reflect;
 423
 424  /*
 425   * The job of this function is to: 1) assign storage to fields, and 2)
 426   * build the vtable.  static fields are assigned real memory, instance
 427   * fields are assigned offsets.
 428   *
 429   * NOTE: we have a contract with the garbage collector here.  Static
 430   * reference fields must not be resolved, until after they have storage
 431   * assigned which is the check used by the collector to see if it
 432   * should indirect the static field reference and mark the object
 433   * pointed to.
 434   *
 435   * Most fields are resolved lazily (i.e. have their class-type
 436   * assigned) when they are accessed the first time by calling as part
 437   * of _Jv_ResolveField, which is allways called after _Jv_PrepareClass.
 438   * Static fields with initializers are resolved as part of this
 439   * function, as are fields with primitive types.
 440   */
 441
 442   if (! _Jv_IsInterpretedClass (klass))
 443     return;
 444
 445   if (klass->state >= JV_STATE_PREPARED)
 446     return;
 447
 448   // Make sure super-class is linked.  This involves taking a lock on
 449   // the super class, so we use the Java method resolveClass, which
 450   // will unlock it properly, should an exception happen.  If there's
 451   // no superclass, do nothing -- Object will already have been
 452   // resolved.
 453
 454   if (klass->superclass)
 455     java::lang::ClassLoader::resolveClass0 (klass->superclass);
 456
 457   _Jv_InterpClass *clz = (_Jv_InterpClass*)klass;
 458
 459   /************ PART ONE: OBJECT LAYOUT ***************/
 460
 461   int instance_size;
 462   int static_size;
 463
 464   // Although java.lang.Object is never interpreted, an interface can
 465   // have a null superclass.
 466   if (clz->superclass)
 467     instance_size = clz->superclass->size();
 468   else
 469     instance_size = java::lang::Object::class$.size();
 470   static_size   = 0;
 471
 472   for (int i = 0; i < clz->field_count; i++)
 473     {
 474       int field_size;
 475       int field_align;
 476
 477       _Jv_Field *field = &clz->fields[i];
 478
 479       if (! field->isRef ())
 480         {
 481           // it's safe to resolve the field here, since it's
 482           // a primitive class, which does not cause loading to happen.
 483           _Jv_ResolveField (field, clz->loader);
 484
 485           field_size = field->type->size ();
 486           field_align = get_alignment_from_class (field->type);
 487         }
 488       else
 489         {
 490           field_size = sizeof (jobject);
 491           field_align = __alignof__ (jobject);
 492         }
 493
 494 #ifndef COMPACT_FIELDS
 495       field->bsize = field_size;
 496 #endif
 497
 498       if (field->flags & Modifier::STATIC)
 499         {
 500           /* this computes an offset into a region we'll allocate
 501              shortly, and then add this offset to the start address */
 502
 503           static_size        = ROUND (static_size, field_align);
 504           field->u.boffset   = static_size;
 505           static_size       += field_size;
 506         }
 507       else
 508         {
 509           instance_size      = ROUND (instance_size, field_align);
 510           field->u.boffset   = instance_size;
 511           instance_size     += field_size;
 512         }
 513     }
 514
 515   // set the instance size for the class
 516   clz->size_in_bytes = instance_size;
 517
 518   // allocate static memory
 519   if (static_size != 0)
 520     {
 521       char *static_data = (char*)_Jv_AllocBytes (static_size);
 522
 523       memset (static_data, 0, static_size);
 524
 525       for (int i = 0; i < clz->field_count; i++)
 526         {
 527           _Jv_Field *field = &clz->fields[i];
 528
 529           if ((field->flags & Modifier::STATIC) != 0)
 530             {
 531               field->u.addr  = static_data + field->u.boffset;
 532
 533               if (clz->field_initializers[i] != 0)
 534                 {
 535                   _Jv_ResolveField (field, clz->loader);
 536                   _Jv_InitField (0, clz, i);
 537                 }
 538             }
 539         }
 540
 541       // now we don't need the field_initializers anymore, so let the
 542       // collector get rid of it!
 543
 544       clz->field_initializers = 0;
 545     }
 546
 547   /************ PART TWO: VTABLE LAYOUT ***************/
 548
 549   /* preparation: build the vtable stubs (even interfaces can)
 550      have code -- for static constructors. */
 551   for (int i = 0; i < clz->method_count; i++)
 552     {
 553       _Jv_MethodBase *imeth = clz->interpreted_methods[i];
 554
 555       if ((clz->methods[i].accflags & Modifier::NATIVE) != 0)
 556         {
 557           // You might think we could use a virtual `ncode' method in
 558           // the _Jv_MethodBase and unify the native and non-native
 559           // cases.  Well, we can't, because we don't allocate these
 560           // objects using `new', and thus they don't get a vtable.
 561           _Jv_JNIMethod *jnim = reinterpret_cast<_Jv_JNIMethod *> (imeth);
 562           clz->methods[i].ncode = jnim->ncode ();
 563         }
 564       else if (imeth != 0)              // it could be abstract
 565         {
 566           _Jv_InterpMethod *im = reinterpret_cast<_Jv_InterpMethod *> (imeth);
 567           _Jv_VerifyMethod (im);
 568           clz->methods[i].ncode = im->ncode ();
 569         }
 570     }
 571
 572   if ((clz->accflags & Modifier::INTERFACE))
 573     {
 574       clz->state = JV_STATE_PREPARED;
 575       clz->notifyAll ();
 576       return;
 577     }
 578
 579   // A class might have so-called "Miranda methods".  This is a method
 580   // that is declared in an interface and not re-declared in an
 581   // abstract class.  Some compilers don't emit declarations for such
 582   // methods in the class; this will give us problems since we expect
 583   // a declaration for any method requiring a vtable entry.  We handle
 584   // this here by searching for such methods and constructing new
 585   // internal declarations for them.  We only need to do this for
 586   // abstract classes.
 587   if ((clz->accflags & Modifier::ABSTRACT))
 588     _Jv_PrepareMissingMethods (clz, clz);
 589
 590   clz->vtable_method_count = -1;
 591   _Jv_MakeVTable (clz);
 592
 593   /* wooha! we're done. */
 594   clz->state = JV_STATE_PREPARED;
 595   clz->notifyAll ();
 596 }
 597
 598 /** Do static initialization for fields with a constant initializer */
 599 void
 600 _Jv_InitField (jobject obj, jclass klass, int index)
 601 {
 602   using namespace java::lang::reflect;
 603
 604   if (obj != 0 && klass == 0)
 605     klass = obj->getClass ();
 606
 607   if (!_Jv_IsInterpretedClass (klass))
 608     return;
 609
 610   _Jv_InterpClass *clz = (_Jv_InterpClass*)klass;
 611
 612   _Jv_Field * field = (&clz->fields[0]) + index;
 613
 614   if (index > clz->field_count)
 615     throw_internal_error ("field out of range");
 616
 617   int init = clz->field_initializers[index];
 618   if (init == 0)
 619     return;
 620
 621   _Jv_Constants *pool = &clz->constants;
 622   int tag = pool->tags[init];
 623
 624   if (! field->isResolved ())
 625     throw_internal_error ("initializing unresolved field");
 626
 627   if (obj==0 && ((field->flags & Modifier::STATIC) == 0))
 628     throw_internal_error ("initializing non-static field with no object");
 629
 630   void *addr = 0;
 631
 632   if ((field->flags & Modifier::STATIC) != 0)
 633     addr = (void*) field->u.addr;
 634   else
 635     addr = (void*) (((char*)obj) + field->u.boffset);
 636
 637   switch (tag)
 638     {
 639     case JV_CONSTANT_String:
 640       {
 641         _Jv_MonitorEnter (clz);
 642         jstring str;
 643         str = _Jv_NewStringUtf8Const (pool->data[init].utf8);
 644         pool->data[init].string = str;
 645         pool->tags[init] = JV_CONSTANT_ResolvedString;
 646         _Jv_MonitorExit (clz);
 647       }
 648       /* fall through */
 649
 650     case JV_CONSTANT_ResolvedString:
 651       if (! (field->type == &StringClass
 652              || field->type == &java::lang::Class::class$))
 653         throw_class_format_error ("string initialiser to non-string field");
 654
 655       *(jstring*)addr = pool->data[init].string;
 656       break;
 657
 658     case JV_CONSTANT_Integer:
 659       {
 660         int value = pool->data[init].i;
 661
 662         if (field->type == JvPrimClass (boolean))
 663           *(jboolean*)addr = (jboolean)value;
 664
 665         else if (field->type == JvPrimClass (byte))
 666           *(jbyte*)addr = (jbyte)value;
 667
 668         else if (field->type == JvPrimClass (char))
 669           *(jchar*)addr = (jchar)value;
 670
 671         else if (field->type == JvPrimClass (short))
 672           *(jshort*)addr = (jshort)value;
 673
 674         else if (field->type == JvPrimClass (int))
 675           *(jint*)addr = (jint)value;
 676
 677         else
 678           throw_class_format_error ("erroneous field initializer");
 679       }
 680       break;
 681
 682     case JV_CONSTANT_Long:
 683       if (field->type != JvPrimClass (long))
 684         throw_class_format_error ("erroneous field initializer");
 685
 686       *(jlong*)addr = _Jv_loadLong (&pool->data[init]);
 687       break;
 688
 689     case JV_CONSTANT_Float:
 690       if (field->type != JvPrimClass (float))
 691         throw_class_format_error ("erroneous field initializer");
 692
 693       *(jfloat*)addr = pool->data[init].f;
 694       break;
 695
 696     case JV_CONSTANT_Double:
 697       if (field->type != JvPrimClass (double))
 698         throw_class_format_error ("erroneous field initializer");
 699
 700       *(jdouble*)addr = _Jv_loadDouble (&pool->data[init]);
 701       break;
 702
 703     default:
 704       throw_class_format_error ("erroneous field initializer");
 705     }
 706 }
 707
 708 static int
 709 get_alignment_from_class (jclass klass)
 710 {
 711   if (klass == JvPrimClass (byte))
 712     return  __alignof__ (jbyte);
 713   else if (klass == JvPrimClass (short))
 714     return  __alignof__ (jshort);
 715   else if (klass == JvPrimClass (int))
 716     return  __alignof__ (jint);
 717   else if (klass == JvPrimClass (long))
 718     return  __alignof__ (jlong);
 719   else if (klass == JvPrimClass (boolean))
 720     return  __alignof__ (jboolean);
 721   else if (klass == JvPrimClass (char))
 722     return  __alignof__ (jchar);
 723   else if (klass == JvPrimClass (float))
 724     return  __alignof__ (jfloat);
 725   else if (klass == JvPrimClass (double))
 726     return  __alignof__ (jdouble);
 727   else
 728     return __alignof__ (jobject);
 729 }
 730
 731
 732 inline static unsigned char*
 733 skip_one_type (unsigned char* ptr)
 734 {
 735   int ch = *ptr++;
 736
 737   while (ch == '[')
 738     {
 739       ch = *ptr++;
 740     }
 741
 742   if (ch == 'L')
 743     {
 744       do { ch = *ptr++; } while (ch != ';');
 745     }
 746
 747   return ptr;
 748 }
 749
 750 static ffi_type*
 751 get_ffi_type_from_signature (unsigned char* ptr)
 752 {
 753   switch (*ptr)
 754     {
 755     case 'L':
 756     case '[':
 757       return &ffi_type_pointer;
 758       break;
 759
 760     case 'Z':
 761       // On some platforms a bool is a byte, on others an int.
 762       if (sizeof (jboolean) == sizeof (jbyte))
 763         return &ffi_type_sint8;
 764       else
 765         {
 766           JvAssert (sizeof (jbyte) == sizeof (jint));
 767           return &ffi_type_sint32;
 768         }
 769       break;
 770
 771     case 'B':
 772       return &ffi_type_sint8;
 773       break;
 774
 775     case 'C':
 776       return &ffi_type_uint16;
 777       break;
 778
 779     case 'S':
 780       return &ffi_type_sint16;
 781       break;
 782
 783     case 'I':
 784       return &ffi_type_sint32;
 785       break;
 786
 787     case 'J':
 788       return &ffi_type_sint64;
 789       break;
 790
 791     case 'F':
 792       return &ffi_type_float;
 793       break;
 794
 795     case 'D':
 796       return &ffi_type_double;
 797       break;
 798
 799     case 'V':
 800       return &ffi_type_void;
 801       break;
 802     }
 803
 804   throw_internal_error ("unknown type in signature");
 805 }
 806
 807 /* this function yields the number of actual arguments, that is, if the
 808  * function is non-static, then one is added to the number of elements
 809  * found in the signature */
 810
 811 int
 812 _Jv_count_arguments (_Jv_Utf8Const *signature,
 813                      jboolean staticp)
 814 {
 815   unsigned char *ptr = (unsigned char*) signature->data;
 816   int arg_count = staticp ? 0 : 1;
 817
 818   /* first, count number of arguments */
 819
 820   // skip '('
 821   ptr++;
 822
 823   // count args
 824   while (*ptr != ')')
 825     {
 826       ptr = skip_one_type (ptr);
 827       arg_count += 1;
 828     }
 829
 830   return arg_count;
 831 }
 832
 833 /* This beast will build a cif, given the signature.  Memory for
 834  * the cif itself and for the argument types must be allocated by the
 835  * caller.
 836  */
 837
 838 static int
 839 init_cif (_Jv_Utf8Const* signature,
 840           int arg_count,
 841           jboolean staticp,
 842           ffi_cif *cif,
 843           ffi_type **arg_types,
 844           ffi_type **rtype_p)
 845 {
 846   unsigned char *ptr = (unsigned char*) signature->data;
 847
 848   int arg_index = 0;            // arg number
 849   int item_count = 0;           // stack-item count
 850
 851   // setup receiver
 852   if (!staticp)
 853     {
 854       arg_types[arg_index++] = &ffi_type_pointer;
 855       item_count += 1;
 856     }
 857
 858   // skip '('
 859   ptr++;
 860
 861   // assign arg types
 862   while (*ptr != ')')
 863     {
 864       arg_types[arg_index++] = get_ffi_type_from_signature (ptr);
 865
 866       if (*ptr == 'J' || *ptr == 'D')
 867         item_count += 2;
 868       else
 869         item_count += 1;
 870
 871       ptr = skip_one_type (ptr);
 872     }
 873
 874   // skip ')'
 875   ptr++;
 876   ffi_type *rtype = get_ffi_type_from_signature (ptr);
 877
 878   ptr = skip_one_type (ptr);
 879   if (ptr != (unsigned char*)signature->data + signature->length)
 880     throw_internal_error ("did not find end of signature");
 881
 882   if (ffi_prep_cif (cif, FFI_DEFAULT_ABI,
 883                     arg_count, rtype, arg_types) != FFI_OK)
 884     throw_internal_error ("ffi_prep_cif failed");
 885
 886   if (rtype_p != NULL)
 887     *rtype_p = rtype;
 888
 889   return item_count;
 890 }
 891
 892 #if FFI_NATIVE_RAW_API
 893 #   define FFI_PREP_RAW_CLOSURE ffi_prep_raw_closure
 894 #   define FFI_RAW_SIZE ffi_raw_size
 895 #else
 896 #   define FFI_PREP_RAW_CLOSURE ffi_prep_java_raw_closure
 897 #   define FFI_RAW_SIZE ffi_java_raw_size
 898 #endif
 899
 900 /* we put this one here, and not in interpret.cc because it
 901  * calls the utility routines _Jv_count_arguments
 902  * which are static to this module.  The following struct defines the
 903  * layout we use for the stubs, it's only used in the ncode method. */
 904
 905 typedef struct {
 906   ffi_raw_closure  closure;
 907   ffi_cif   cif;
 908   ffi_type *arg_types[0];
 909 } ncode_closure;
 910
 911 typedef void (*ffi_closure_fun) (ffi_cif*,void*,ffi_raw*,void*);
 912
 913 void *
 914 _Jv_InterpMethod::ncode ()
 915 {
 916   using namespace java::lang::reflect;
 917
 918   if (self->ncode != 0)
 919     return self->ncode;
 920
 921   jboolean staticp = (self->accflags & Modifier::STATIC) != 0;
 922   int arg_count = _Jv_count_arguments (self->signature, staticp);
 923
 924   ncode_closure *closure =
 925     (ncode_closure*)_Jv_AllocBytes (sizeof (ncode_closure)
 926                                         + arg_count * sizeof (ffi_type*));
 927
 928   init_cif (self->signature,
 929             arg_count,
 930             staticp,
 931             &closure->cif,
 932             &closure->arg_types[0],
 933             NULL);
 934
 935   ffi_closure_fun fun;
 936
 937   args_raw_size = FFI_RAW_SIZE (&closure->cif);
 938
 939   JvAssert ((self->accflags & Modifier::NATIVE) == 0);
 940
 941   if ((self->accflags & Modifier::SYNCHRONIZED) != 0)
 942     {
 943       if (staticp)
 944         fun = (ffi_closure_fun)&_Jv_InterpMethod::run_synch_class;
 945       else
 946         fun = (ffi_closure_fun)&_Jv_InterpMethod::run_synch_object;
 947     }
 948   else
 949     {
 950       if (staticp)
 951         fun = (ffi_closure_fun)&_Jv_InterpMethod::run_class;
 952       else
 953         fun = (ffi_closure_fun)&_Jv_InterpMethod::run_normal;
 954     }
 955
 956   FFI_PREP_RAW_CLOSURE (&closure->closure,
 957                         &closure->cif,
 958                         fun,
 959                         (void*)this);
 960
 961   self->ncode = (void*)closure;
 962   return self->ncode;
 963 }
 964
 965 void *
 966 _Jv_JNIMethod::ncode ()
 967 {
 968   using namespace java::lang::reflect;
 969
 970   if (self->ncode != 0)
 971     return self->ncode;
 972
 973   jboolean staticp = (self->accflags & Modifier::STATIC) != 0;
 974   int arg_count = _Jv_count_arguments (self->signature, staticp);
 975
 976   ncode_closure *closure =
 977     (ncode_closure*)_Jv_AllocBytes (sizeof (ncode_closure)
 978                                     + arg_count * sizeof (ffi_type*));
 979
 980   ffi_type *rtype;
 981   init_cif (self->signature,
 982             arg_count,
 983             staticp,
 984             &closure->cif,
 985             &closure->arg_types[0],
 986             &rtype);
 987
 988   ffi_closure_fun fun;
 989
 990   args_raw_size = FFI_RAW_SIZE (&closure->cif);
 991
 992   // Initialize the argument types and CIF that represent the actual
 993   // underlying JNI function.
 994   int extra_args = 1;
 995   if ((self->accflags & Modifier::STATIC))
 996     ++extra_args;
 997   jni_arg_types = (ffi_type **) _Jv_Malloc ((extra_args + arg_count)
 998                                             * sizeof (ffi_type *));
 999   int offset = 0;
1000   jni_arg_types[offset++] = &ffi_type_pointer;
1001   if ((self->accflags & Modifier::STATIC))
1002     jni_arg_types[offset++] = &ffi_type_pointer;
1003   memcpy (&jni_arg_types[offset], &closure->arg_types[0],
1004           arg_count * sizeof (ffi_type *));
1005
1006   // NOTE: This must agree with the JNICALL definition in jni.h
1007 #ifdef WIN32
1008 #define FFI_JNI_ABI FFI_STDCALL
1009 #else
1010 #define FFI_JNI_ABI FFI_DEFAULT_ABI
1011 #endif
1012
1013   if (ffi_prep_cif (&jni_cif, FFI_JNI_ABI,
1014                     extra_args + arg_count, rtype,
1015                     jni_arg_types) != FFI_OK)
1016     throw_internal_error ("ffi_prep_cif failed for JNI function");
1017
1018   JvAssert ((self->accflags & Modifier::NATIVE) != 0);
1019
1020   // FIXME: for now we assume that all native methods for
1021   // interpreted code use JNI.
1022   fun = (ffi_closure_fun) &_Jv_JNIMethod::call;
1023
1024   FFI_PREP_RAW_CLOSURE (&closure->closure,
1025                         &closure->cif,
1026                         fun,
1027                         (void*) this);
1028
1029   self->ncode = (void *) closure;
1030   return self->ncode;
1031 }
1032
1033
1034 /* A _Jv_ResolvedMethod is what is put in the constant pool for a
1035  * MethodRef or InterfacemethodRef.  */
1036 static _Jv_ResolvedMethod*
1037 _Jv_BuildResolvedMethod (_Jv_Method* method,
1038                          jclass      klass,
1039                          jboolean staticp,
1040                          jint vtable_index)
1041 {
1042   int arg_count = _Jv_count_arguments (method->signature, staticp);
1043
1044   _Jv_ResolvedMethod* result = (_Jv_ResolvedMethod*)
1045     _Jv_AllocBytes (sizeof (_Jv_ResolvedMethod)
1046                     + arg_count*sizeof (ffi_type*));
1047
1048   result->stack_item_count
1049     = init_cif (method->signature,
1050                 arg_count,
1051                 staticp,
1052                 &result->cif,
1053                 &result->arg_types[0],
1054                 NULL);
1055
1056   result->vtable_index        = vtable_index;
1057   result->method              = method;
1058   result->klass               = klass;
1059
1060   return result;
1061 }
1062
1063
1064 static void
1065 throw_class_format_error (jstring msg)
1066 {
1067   throw (msg
1068          ? new java::lang::ClassFormatError (msg)
1069          : new java::lang::ClassFormatError);
1070 }
1071
1072 static void
1073 throw_class_format_error (char *msg)
1074 {
1075   throw_class_format_error (JvNewStringLatin1 (msg));
1076 }
1077
1078 static void
1079 throw_internal_error (char *msg)
1080 {
1081   throw new java::lang::InternalError (JvNewStringLatin1 (msg));
1082 }
1083
1084
1085 #endif /* INTERPRETER */