1 // jvm.h - Header file for private implementation information. -*- c++ -*-
3 /* Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation
5 This file is part of libgcj.
7 This software is copyrighted work licensed under the terms of the
8 Libgcj License. Please consult the file "LIBGCJ_LICENSE" for
11 #ifndef __JAVA_JVM_H__
12 #define __JAVA_JVM_H__
14 // Define this before including jni.h.
15 // jni.h is included by jvmpi.h, which might be included. We define
16 // this unconditionally because it is convenient and it lets other
17 // files include jni.h without difficulty.
18 #define __GCJ_JNI_IMPL__
20 #include <gcj/javaprims.h>
22 #include <java-assert.h>
23 #include <java-threads.h>
24 // Must include java-gc.h before Object.h for the implementation.
27 #include <java/lang/Object.h>
29 // Include cni.h before field.h to enable all definitions. FIXME.
31 #include <gcj/field.h>
33 /* Macro for possible unused arguments. */
34 #define MAYBE_UNUSED __attribute__((__unused__))
36 /* Structure of the virtual table. */
40 typedef struct { void *pc
, *gp
; } vtable_elt
;
42 typedef void *vtable_elt
;
47 // This must be last, as derived classes "extend" this by
48 // adding new data members.
52 void *get_method(int i
) { return &method
[i
]; }
53 void set_method(int i
, void *fptr
) { method
[i
] = *(vtable_elt
*)fptr
; }
56 // We know that get_finalizer is only used for checking whether
57 // this object needs to have a finalizer registered. So it is
58 // safe to simply return just the PC component of the vtable
60 return ((vtable_elt
*)(get_method(0)))->pc
;
63 void *get_method(int i
) { return method
[i
]; }
64 void set_method(int i
, void *fptr
) { method
[i
] = fptr
; }
65 void *get_finalizer() { return get_method(0); }
68 static size_t vtable_elt_size() { return sizeof(vtable_elt
); }
70 // Given a method index, return byte offset from the vtable pointer.
71 static jint
idx_to_offset (int index
)
73 return (2 * sizeof (void *)) + (index
* vtable_elt_size ());
75 static _Jv_VTable
*new_vtable (int count
);
78 // Number of virtual methods on object. FIXME: it sucks that we have
79 // to keep this up to date by hand.
80 #define NUM_OBJECT_METHODS 5
85 jint i
; // Also stores smaller integral types.
87 jint ia
[1]; // Half of _Jv_word2.
90 #if SIZEOF_VOID_P == 8
91 // We can safely put a long or a double in here without increasing
92 // the size of _Jv_Word; we take advantage of this in the interpreter.
99 struct _Jv_Field
*field
;
100 struct _Jv_Utf8Const
*utf8
;
101 struct _Jv_ResolvedMethod
*rmethod
;
119 jdouble double_value
;
120 jobject object_value
;
123 /* Extract a character from a Java-style Utf8 string.
124 * PTR points to the current character.
125 * LIMIT points to the end of the Utf8 string.
126 * PTR is incremented to point after the character thta gets returns.
127 * On an error, -1 is returned. */
128 #define UTF8_GET(PTR, LIMIT) \
129 ((PTR) >= (LIMIT) ? -1 \
130 : *(PTR) < 128 ? *(PTR)++ \
131 : (*(PTR)&0xE0) == 0xC0 && ((PTR)+=2)<=(LIMIT) && ((PTR)[-1]&0xC0) == 0x80 \
132 ? (((PTR)[-2] & 0x1F) << 6) + ((PTR)[-1] & 0x3F) \
133 : (*(PTR) & 0xF0) == 0xE0 && ((PTR) += 3) <= (LIMIT) \
134 && ((PTR)[-2] & 0xC0) == 0x80 && ((PTR)[-1] & 0xC0) == 0x80 \
135 ? (((PTR)[-3]&0x0F) << 12) + (((PTR)[-2]&0x3F) << 6) + ((PTR)[-1]&0x3F) \
138 extern int _Jv_strLengthUtf8(char* str
, int len
);
140 typedef struct _Jv_Utf8Const Utf8Const
;
141 _Jv_Utf8Const
*_Jv_makeUtf8Const (char *s
, int len
);
142 _Jv_Utf8Const
*_Jv_makeUtf8Const (jstring string
);
143 extern jboolean
_Jv_equalUtf8Consts (const _Jv_Utf8Const
*, const _Jv_Utf8Const
*);
144 extern jboolean
_Jv_equal (_Jv_Utf8Const
*, jstring
, jint
);
145 extern jboolean
_Jv_equaln (_Jv_Utf8Const
*, jstring
, jint
);
147 /* Helper class which converts a jstring to a temporary char*.
148 Uses the supplied buffer, if non-null. Otherwise, allocates
149 the buffer on the heap. Use the JV_TEMP_UTF_STRING macro,
150 which follows, to automatically allocate a stack buffer if
151 the string is small enough. */
152 class _Jv_TempUTFString
155 _Jv_TempUTFString(jstring jstr
, char* buf
=0);
156 ~_Jv_TempUTFString();
159 operator const char*() const
163 const char* buf() const
177 inline _Jv_TempUTFString::_Jv_TempUTFString (jstring jstr
, char* buf
)
178 : buf_(0), heapAllocated_(false)
181 jsize len
= JvGetStringUTFLength (jstr
);
186 buf_
= (char*) _Jv_Malloc (len
+1);
187 heapAllocated_
= true;
190 JvGetStringUTFRegion (jstr
, 0, jstr
->length(), buf_
);
194 inline _Jv_TempUTFString::~_Jv_TempUTFString ()
200 /* Macro which uses _Jv_TempUTFString. Allocates a stack-based
201 buffer if the string and its null terminator are <= 256
202 characters in length. Otherwise, a heap-based buffer is
203 used. The parameters to this macro are the variable name
204 which is an instance of _Jv_TempUTFString (above) and a
209 jstring jstr = getAJString();
210 JV_TEMP_UTF_STRING(utfstr, jstr);
211 printf("The string is: %s\n", utfstr.buf());
214 #define JV_TEMP_UTF_STRING(utfstr, jstr) \
215 jstring utfstr##thejstr = (jstr); \
216 jsize utfstr##_len = utfstr##thejstr ? JvGetStringUTFLength (utfstr##thejstr) + 1 : 0; \
217 char utfstr##_buf[utfstr##_len <= 256 ? utfstr##_len : 0]; \
218 _Jv_TempUTFString utfstr(utfstr##thejstr, sizeof(utfstr##_buf)==0 ? 0 : utfstr##_buf)
222 /* Some constants used during lookup of special class methods. */
223 extern _Jv_Utf8Const
*void_signature
; /* "()V" */
224 extern _Jv_Utf8Const
*clinit_name
; /* "<clinit>" */
225 extern _Jv_Utf8Const
*init_name
; /* "<init>" */
226 extern _Jv_Utf8Const
*finit_name
; /* "finit$", */
228 /* Set to true by _Jv_CreateJavaVM. */
229 extern bool runtimeInitialized
;
231 /* Print out class names as they are initialized. */
232 extern bool verbose_class_flag
;
234 /* When true, enable the bytecode verifier and BC-ABI verification. */
235 extern bool verifyClasses
;
238 // This class handles all aspects of class preparation and linking.
242 static _Jv_Field
*find_field_helper(jclass
, _Jv_Utf8Const
*, _Jv_Utf8Const
*,
244 static _Jv_Field
*find_field(jclass
, jclass
, jclass
*, _Jv_Utf8Const
*,
246 static void prepare_constant_time_tables(jclass
);
247 static jshort
get_interfaces(jclass
, _Jv_ifaces
*);
248 static void link_symbol_table(jclass
);
249 static void link_exception_table(jclass
);
250 static void layout_interface_methods(jclass
);
251 static void layout_vtable_methods(jclass
);
252 static void set_vtable_entries(jclass
, _Jv_VTable
*);
253 static void make_vtable(jclass
);
254 static void ensure_fields_laid_out(jclass
);
255 static void ensure_class_linked(jclass
);
256 static void ensure_supers_installed(jclass
);
257 static void add_miranda_methods(jclass
, jclass
);
258 static void ensure_method_table_complete(jclass
);
259 static void verify_class(jclass
);
260 static jshort
find_iindex(jclass
*, jshort
*, jshort
);
261 static jshort
indexof(void *, void **, jshort
);
262 static int get_alignment_from_class(jclass
);
263 static void generate_itable(jclass
, _Jv_ifaces
*, jshort
*);
264 static jshort
append_partial_itable(jclass
, jclass
, void **, jshort
);
265 static _Jv_Method
*search_method_in_class (jclass
, jclass
,
271 static bool has_field_p (jclass
, _Jv_Utf8Const
*);
272 static void print_class_loaded (jclass
);
273 static void resolve_class_ref (jclass
, jclass
*);
274 static void wait_for_state(jclass
, int);
275 static _Jv_word
resolve_pool_entry (jclass
, int);
276 static void resolve_field (_Jv_Field
*, java::lang::ClassLoader
*);
277 static void verify_type_assertions (jclass
);
280 /* Type of pointer used as finalizer. */
281 typedef void _Jv_FinalizerFunc (jobject
);
283 /* Allocate space for a new Java object. */
284 void *_Jv_AllocObj (jsize size
, jclass cl
) __attribute__((__malloc__
));
285 /* Allocate space for a potentially uninitialized pointer-free object.
286 Interesting only with JV_HASH_SYNCHRONIZATION. */
287 void *_Jv_AllocPtrFreeObj (jsize size
, jclass cl
) __attribute__((__malloc__
));
288 /* Allocate space for an array of Java objects. */
289 void *_Jv_AllocArray (jsize size
, jclass cl
) __attribute__((__malloc__
));
290 /* Allocate space that is known to be pointer-free. */
291 void *_Jv_AllocBytes (jsize size
) __attribute__((__malloc__
));
292 /* Allocate space for a new non-Java object, which does not have the usual
293 Java object header but may contain pointers to other GC'ed objects. */
294 void *_Jv_AllocRawObj (jsize size
) __attribute__((__malloc__
));
295 /* Explicitly throw an out-of-memory exception. */
296 void _Jv_ThrowNoMemory() __attribute__((__noreturn__
));
297 /* Allocate an object with a single pointer. The first word is reserved
298 for the GC, and the second word is the traced pointer. */
299 void *_Jv_AllocTraceOne (jsize size
/* incl. reserved slot */);
300 /* Ditto, but for two traced pointers. */
301 void *_Jv_AllocTraceTwo (jsize size
/* incl. reserved slot */);
302 /* Initialize the GC. */
303 void _Jv_InitGC (void);
304 /* Register a finalizer. */
305 void _Jv_RegisterFinalizer (void *object
, _Jv_FinalizerFunc
*method
);
306 /* Compute the GC descriptor for a class */
307 void * _Jv_BuildGCDescr(jclass
);
309 /* Allocate some unscanned, unmoveable memory. Return NULL if out of
311 void *_Jv_MallocUnchecked (jsize size
) __attribute__((__malloc__
));
313 /* Initialize finalizers. The argument is a function to be called
314 when a finalizer is ready to be run. */
315 void _Jv_GCInitializeFinalizers (void (*notifier
) (void));
316 /* Run finalizers for objects ready to be finalized.. */
317 void _Jv_RunFinalizers (void);
318 /* Run all finalizers. Should be called only before exit. */
319 void _Jv_RunAllFinalizers (void);
321 void _Jv_RunGC (void);
322 /* Disable and enable GC. */
323 void _Jv_DisableGC (void);
324 void _Jv_EnableGC (void);
325 /* Register a disappearing link. This is a field F which should be
326 cleared when *F is found to be inaccessible. This is used in the
327 implementation of java.lang.ref.Reference. */
328 void _Jv_GCRegisterDisappearingLink (jobject
*objp
);
329 /* Return true if OBJECT should be reclaimed. This is used to
330 implement soft references. */
331 jboolean
_Jv_GCCanReclaimSoftReference (jobject obj
);
333 /* Register a finalizer for a String object. This is only used by
334 the intern() implementation. */
335 void _Jv_RegisterStringFinalizer (jobject str
);
336 /* This is called to actually finalize a possibly-intern()d String. */
337 void _Jv_FinalizeString (jobject str
);
339 /* Return approximation of total size of heap. */
340 long _Jv_GCTotalMemory (void);
341 /* Return approximation of total free memory. */
342 long _Jv_GCFreeMemory (void);
344 /* Set initial heap size. If SIZE==0, ignore. Should be run before
345 _Jv_InitGC. Not required to have any actual effect. */
346 void _Jv_GCSetInitialHeapSize (size_t size
);
348 /* Set maximum heap size. If SIZE==0, unbounded. Should be run
349 before _Jv_InitGC. Not required to have any actual effect. */
350 void _Jv_GCSetMaximumHeapSize (size_t size
);
352 /* External interface to setting the heap size. Parses ARG (a number
353 which can optionally have "k" or "m" appended and calls
354 _Jv_GCSetInitialHeapSize. */
355 void _Jv_SetInitialHeapSize (const char *arg
);
357 /* External interface to setting the maximum heap size. Parses ARG (a
358 number which can optionally have "k" or "m" appended and calls
359 _Jv_GCSetMaximumHeapSize. */
360 void _Jv_SetMaximumHeapSize (const char *arg
);
362 /* Free the method cache, if one was allocated. This is only called
363 during thread deregistration. */
364 void _Jv_FreeMethodCache ();
366 extern "C" void JvRunMain (jclass klass
, int argc
, const char **argv
);
367 void _Jv_RunMain (jclass klass
, const char *name
, int argc
, const char **argv
,
370 void _Jv_RunMain (struct _Jv_VMInitArgs
*vm_args
, jclass klass
,
371 const char *name
, int argc
, const char **argv
, bool is_jar
);
373 // Delayed until after _Jv_AllocBytes is declared.
375 // Note that we allocate this as unscanned memory -- the vtables
376 // are handled specially by the GC.
379 _Jv_VTable::new_vtable (int count
)
381 size_t size
= sizeof(_Jv_VTable
) + (count
- 1) * vtable_elt_size ();
382 return (_Jv_VTable
*) _Jv_AllocBytes (size
);
385 // Determine if METH gets an entry in a VTable.
386 static inline jboolean
_Jv_isVirtualMethod (_Jv_Method
*meth
)
388 using namespace java::lang::reflect
;
389 return (((meth
->accflags
& (Modifier::STATIC
| Modifier::PRIVATE
)) == 0)
390 && meth
->name
->first() != '<');
393 // This function is used to determine the hash code of an object.
395 _Jv_HashCode (jobject obj
)
397 // This was chosen to yield relatively well distributed results on
398 // both 32- and 64-bit architectures. Note 0x7fffffff is prime.
399 // FIXME: we assume sizeof(long) == sizeof(void *).
400 return (jint
) ((unsigned long) obj
% 0x7fffffff);
403 // Return a raw pointer to the elements of an array given the array
404 // and its element type. You might think we could just pick a single
405 // array type and use elements() on it, but we can't because we must
406 // account for alignment of the element type. When ARRAY is null, we
407 // obtain the number of bytes taken by the base part of the array.
409 _Jv_GetArrayElementFromElementType (jobject array
,
413 if (element_type
== JvPrimClass (byte
))
414 elts
= (char *) elements ((jbyteArray
) array
);
415 else if (element_type
== JvPrimClass (short))
416 elts
= (char *) elements ((jshortArray
) array
);
417 else if (element_type
== JvPrimClass (int))
418 elts
= (char *) elements ((jintArray
) array
);
419 else if (element_type
== JvPrimClass (long))
420 elts
= (char *) elements ((jlongArray
) array
);
421 else if (element_type
== JvPrimClass (boolean
))
422 elts
= (char *) elements ((jbooleanArray
) array
);
423 else if (element_type
== JvPrimClass (char))
424 elts
= (char *) elements ((jcharArray
) array
);
425 else if (element_type
== JvPrimClass (float))
426 elts
= (char *) elements ((jfloatArray
) array
);
427 else if (element_type
== JvPrimClass (double))
428 elts
= (char *) elements ((jdoubleArray
) array
);
430 elts
= (char *) elements ((jobjectArray
) array
);
434 extern "C" void _Jv_ThrowBadArrayIndex (jint bad_index
)
435 __attribute__((noreturn
));
436 extern "C" void _Jv_ThrowNullPointerException (void)
437 __attribute__((noreturn
));
438 extern "C" jobject
_Jv_NewArray (jint type
, jint size
)
439 __attribute__((__malloc__
));
440 extern "C" jobject
_Jv_NewMultiArray (jclass klass
, jint dims
, ...)
441 __attribute__((__malloc__
));
442 extern "C" void *_Jv_CheckCast (jclass klass
, jobject obj
);
443 extern "C" void *_Jv_LookupInterfaceMethod (jclass klass
, Utf8Const
*name
,
444 Utf8Const
*signature
);
445 extern "C" void *_Jv_LookupInterfaceMethodIdx (jclass klass
, jclass iface
,
447 extern "C" void _Jv_CheckArrayStore (jobject array
, jobject obj
);
448 extern "C" void _Jv_RegisterClass (jclass klass
);
449 extern "C" void _Jv_RegisterClasses (const jclass
*classes
);
450 extern "C" void _Jv_RegisterClasses_Counted (const jclass
*classes
,
452 extern "C" void _Jv_RegisterResource (void *vptr
);
453 extern void _Jv_UnregisterClass (_Jv_Utf8Const
*, java::lang::ClassLoader
*);
455 extern jclass
_Jv_FindClass (_Jv_Utf8Const
*name
,
456 java::lang::ClassLoader
*loader
);
457 extern jclass
_Jv_FindClassFromSignature (char *,
458 java::lang::ClassLoader
*loader
,
460 extern void _Jv_GetTypesFromSignature (jmethodID method
,
461 jclass declaringClass
,
462 JArray
<jclass
> **arg_types_out
,
463 jclass
*return_type_out
);
465 extern jboolean
_Jv_CheckAccess (jclass self_klass
, jclass other_klass
,
468 extern jobject
_Jv_CallAnyMethodA (jobject obj
, jclass return_type
,
469 jmethodID meth
, jboolean is_constructor
,
470 JArray
<jclass
> *parameter_types
,
472 jclass iface
= NULL
);
475 extern void _Jv_CallAnyMethodA (jobject obj
,
478 jboolean is_constructor
,
479 jboolean is_virtual_call
,
480 JArray
<jclass
> *parameter_types
,
483 jboolean is_jni_call
= true,
484 jclass iface
= NULL
);
486 extern jobject
_Jv_NewMultiArray (jclass
, jint ndims
, jint
* dims
)
487 __attribute__((__malloc__
));
489 extern "C" void _Jv_ThrowAbstractMethodError () __attribute__((__noreturn__
));
491 /* Checked divide subroutines. */
494 jint
_Jv_divI (jint
, jint
);
495 jint
_Jv_remI (jint
, jint
);
496 jlong
_Jv_divJ (jlong
, jlong
);
497 jlong
_Jv_remJ (jlong
, jlong
);
500 /* Get the number of arguments (cf. argc) or 0 if our argument
501 list was never initialized. */
502 extern int _Jv_GetNbArgs (void);
504 /* Get the specified argument (cf. argv[index]) or "" if either
505 our argument list was never initialized or the specified index
507 extern const char * _Jv_GetSafeArg (int index
);
509 /* Sets our argument list. Can be used by programs with non-standard
511 extern void _Jv_SetArgs (int argc
, const char **argv
);
513 /* Get the name of the running executable. */
514 extern const char *_Jv_ThisExecutable (void);
516 /* Return a pointer to a symbol in executable or loaded library. */
517 void *_Jv_FindSymbolInExecutable (const char *);
519 /* Initialize JNI. */
520 extern void _Jv_JNI_Init (void);
522 /* Get or set the per-thread JNIEnv used by the invocation API. */
523 _Jv_JNIEnv
*_Jv_GetCurrentJNIEnv ();
524 void _Jv_SetCurrentJNIEnv (_Jv_JNIEnv
*);
527 void _Jv_FreeJNIEnv (_Jv_JNIEnv
*);
530 void _Jv_FreeJNIEnv (_Jv_JNIEnv
*);
533 _Jv_JavaVM
*_Jv_GetJavaVM ();
535 // Some verification functions from defineclass.cc.
536 bool _Jv_VerifyFieldSignature (_Jv_Utf8Const
*sig
);
537 bool _Jv_VerifyMethodSignature (_Jv_Utf8Const
*sig
);
538 bool _Jv_VerifyClassName (unsigned char* ptr
, _Jv_ushort length
);
539 bool _Jv_VerifyClassName (_Jv_Utf8Const
*name
);
540 bool _Jv_VerifyIdentifier (_Jv_Utf8Const
*);
541 bool _Jv_ClassNameSamePackage (_Jv_Utf8Const
*name1
, _Jv_Utf8Const
*name2
);
543 struct _Jv_core_chain
550 struct _Jv_core_chain
*next
;
553 // This is called when new core data is loaded.
554 extern void (*_Jv_RegisterCoreHook
) (_Jv_core_chain
*);
556 _Jv_core_chain
*_Jv_FindCore (_Jv_core_chain
*node
, jstring name
);
557 void _Jv_FreeCoreChain (_Jv_core_chain
*chain
);
563 extern void (*_Jv_JVMPI_Notify_OBJECT_ALLOC
) (JVMPI_Event
*event
);
564 extern void (*_Jv_JVMPI_Notify_THREAD_START
) (JVMPI_Event
*event
);
565 extern void (*_Jv_JVMPI_Notify_THREAD_END
) (JVMPI_Event
*event
);
568 /* FIXME: this should really be defined in some more generic place */
569 #define ROUND(V, A) (((((unsigned) (V))-1) | ((A)-1))+1)
571 extern void _Jv_RegisterBootstrapPackages ();
573 #define FLAG_BINARYCOMPAT_ABI (1<<31) /* Class is built with the BC-ABI. */
575 #define FLAG_BOOTSTRAP_LOADER (1<<30) /* Used when defining a class that
576 should be loaded by the bootstrap
579 // These are used to find ABI versions we recognize.
580 #define GCJ_CXX_ABI_VERSION (__GNUC__ * 100000 + __GNUC_MINOR__ * 1000)
582 // This is the old-style BC version ID used by GCJ 4.0.0.
583 #define OLD_GCJ_40_BC_ABI_VERSION (4 * 10000 + 0 * 10 + 5)
585 // New style version IDs used by GCJ 4.0.1 and later.
586 #define GCJ_40_BC_ABI_VERSION (4 * 100000 + 0 * 1000)
589 _Jv_CheckABIVersion (unsigned long value
)
591 // We are compatible with GCJ 4.0.0 BC-ABI classes. This release used a
592 // different format for the version ID string.
593 if (value
== OLD_GCJ_40_BC_ABI_VERSION
)
596 // The 20 low-end bits are used for the version number.
597 unsigned long version
= value
& 0xfffff;
599 if (value
& FLAG_BINARYCOMPAT_ABI
)
601 int abi_rev
= version
% 100;
602 int abi_ver
= version
- abi_rev
;
603 if (abi_ver
== GCJ_40_BC_ABI_VERSION
&& abi_rev
<= 0)
608 return version
== GCJ_CXX_ABI_VERSION
;
614 _Jv_ClassForBootstrapLoader (unsigned long value
)
616 return (value
& FLAG_BOOTSTRAP_LOADER
);
619 // It makes the source cleaner if we simply always define this
620 // function. If the interpreter is not built, it will never return
622 extern inline jboolean
623 _Jv_IsInterpretedClass (jclass c
)
625 return (c
->accflags
& java::lang::reflect::Modifier::INTERPRETED
) != 0;
628 // Return true if the class was compiled with the BC ABI.
629 extern inline jboolean
630 _Jv_IsBinaryCompatibilityABI (jclass c
)
632 // There isn't really a better test for the ABI type at this point,
633 // that will work once the class has been registered.
634 return c
->otable_syms
|| c
->atable_syms
|| c
->itable_syms
;
637 #endif /* __JAVA_JVM_H__ */