1 // java-interp.h - Header file for the bytecode interpreter. -*- c++ -*-
3 /* Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007 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_INTERP_H__
12 #define __JAVA_INTERP_H__
15 #include <java-cpool.h>
16 #include <gnu/gcj/runtime/NameFinder.h>
29 #include <java/lang/Class.h>
30 #include <java/lang/ClassLoader.h>
31 #include <java/lang/reflect/Modifier.h>
32 #include <java/lang/Thread.h>
33 #include <gnu/gcj/RawData.h>
35 // Define this to get the direct-threaded interpreter. If undefined,
36 // we revert to a basic bytecode interpreter. The former is faster
37 // but uses more memory.
38 #define DIRECT_THREADED
42 struct _Jv_ResolvedMethod;
44 void _Jv_InitInterpreter ();
45 void _Jv_DefineClass (jclass, jbyteArray, jint, jint,
46 java::security::ProtectionDomain *,
49 void _Jv_InitField (jobject, jclass, int);
50 void * _Jv_AllocMethodInvocation (jsize size);
51 int _Jv_count_arguments (_Jv_Utf8Const *signature,
52 jboolean staticp = true);
53 void _Jv_VerifyMethod (_Jv_InterpMethod *method);
54 void _Jv_CompileMethod (_Jv_InterpMethod* method);
55 int _Jv_init_cif (_Jv_Utf8Const* signature,
62 /* the interpreter is written in C++, primarily because it makes it easy for
63 * the entire thing to be "friend" with class Class. */
65 class _Jv_InterpClass;
66 class _Jv_InterpMethod;
68 // Before a method is "compiled" we store values as the bytecode PC,
69 // an int. Afterwards we store them as pointers into the prepared
77 class _Jv_InterpException
79 _Jv_InterpPC start_pc;
81 _Jv_InterpPC handler_pc;
82 _Jv_InterpPC handler_type;
84 friend class _Jv_ClassReader;
85 friend class _Jv_InterpMethod;
86 friend class _Jv_BytecodeVerifier;
89 // Base class for method representations. Subclasses are interpreted
94 // The class which defined this method.
95 jclass defining_class;
97 // The method description.
100 // Size of raw arguments.
101 _Jv_ushort args_raw_size;
103 friend class _Jv_InterpreterEngine;
106 _Jv_Method *get_method ()
112 // The type of the PC depends on whether we're doing direct threading
113 // or a more ordinary bytecode interpreter.
114 #ifdef DIRECT_THREADED
115 // Slot in the "compiled" form of the bytecode.
120 // An integer value used by an instruction.
122 // A pointer value used by an instruction.
126 typedef insn_slot *pc_t;
128 typedef unsigned char *pc_t;
132 // This structure holds the bytecode pc and corresponding source code
133 // line number. An array (plus length field) of this structure is put
134 // in each _Jv_InterpMethod and used to resolve the (internal) program
135 // counter of the interpreted method to an actual java source file
137 struct _Jv_LineTableEntry
147 // This structure holds local variable information.
148 // Like _Jv_LineTableEntry above, it is remapped when the method is
149 // compiled for direct threading.
150 struct _Jv_LocalVarTableEntry
152 // First PC value at which variable is live
159 // length of visibility of variable
168 // stack slot number (long and double occupy slot and slot + 1)
172 class _Jv_InterpMethod : public _Jv_MethodBase
174 // Breakpoint instruction
175 static pc_t breakpoint_insn;
176 #ifdef DIRECT_THREADED
177 static insn_slot bp_insn_slot;
180 // Mutex to prevent a data race between threads when rewriting
181 // instructions. See interpret-run.cc for an explanation of its use.
182 static _Jv_Mutex_t rewrite_insn_mutex;
184 // The count of threads executing this method.
190 static unsigned char bp_insn_opcode;
193 _Jv_ushort max_stack;
194 _Jv_ushort max_locals;
197 _Jv_ushort exc_count;
200 // Length of the line_table - when this is zero then line_table is NULL.
202 _Jv_LineTableEntry *line_table;
204 // The local variable table length and the table itself
205 int local_var_table_len;
206 _Jv_LocalVarTableEntry *local_var_table;
209 int number_insn_slots;
211 unsigned char* bytecode ()
214 ((unsigned char*)this)
215 + ROUND((sizeof (_Jv_InterpMethod)
216 + exc_count*sizeof (_Jv_InterpException)), 4);
219 _Jv_InterpException * exceptions ()
221 return (_Jv_InterpException*) (this+1);
224 static size_t size (int exc_count, int code_length)
227 ROUND ((sizeof (_Jv_InterpMethod)
228 + (exc_count * sizeof (_Jv_InterpException))), 4)
232 // return the method's invocation pointer (a stub).
233 void *ncode (jclass);
234 void compile (const void * const *);
236 #if FFI_NATIVE_RAW_API
237 # define INTERP_FFI_RAW_TYPE ffi_raw
239 # define INTERP_FFI_RAW_TYPE ffi_java_raw
242 static void run_normal (ffi_cif*, void*, INTERP_FFI_RAW_TYPE*, void*);
243 static void run_synch_object (ffi_cif*, void*, INTERP_FFI_RAW_TYPE*, void*);
244 static void run_class (ffi_cif*, void*, INTERP_FFI_RAW_TYPE*, void*);
245 static void run_synch_class (ffi_cif*, void*, INTERP_FFI_RAW_TYPE*, void*);
247 static void run_normal_debug (ffi_cif*, void*, INTERP_FFI_RAW_TYPE*, void*);
248 static void run_synch_object_debug (ffi_cif*, void*, INTERP_FFI_RAW_TYPE*,
250 static void run_class_debug (ffi_cif*, void*, INTERP_FFI_RAW_TYPE*, void*);
251 static void run_synch_class_debug (ffi_cif*, void*, INTERP_FFI_RAW_TYPE*,
254 static void run (void *, INTERP_FFI_RAW_TYPE *, _Jv_InterpMethod *);
255 static void run_debug (void *, INTERP_FFI_RAW_TYPE *, _Jv_InterpMethod *);
259 // Returns source file line number for given PC value, or -1 if line
260 // number info is unavailable.
261 int get_source_line(pc_t mpc);
265 // Convenience function for indexing bytecode PC/insn slots in
266 // line tables for JDWP
267 jlong insn_index (pc_t pc);
269 // Helper function used to check if there is a handler for an exception
270 // present at this code index
271 jboolean check_handler (pc_t *pc, _Jv_InterpMethod *meth,
272 java::lang::Throwable *ex);
274 /* Get the line table for this method.
275 * start is the lowest index in the method
276 * end is the highest index in the method
277 * line_numbers is an array to hold the list of source line numbers
278 * code_indices is an array to hold the corresponding list of code indices
280 void get_line_table (jlong& start, jlong& end, jintArray& line_numbers,
281 jlongArray& code_indices);
283 int get_max_locals ()
285 return static_cast<int> (max_locals);
288 /* Get info for a local variable of this method.
289 * If there is no loca_var_table for this method it will return -1.
290 * table_slot indicates which slot in the local_var_table to get, if there is
291 * no variable at this location it will return 0.
292 * Otherwise, it will return the number of table slots after the selected
293 * slot, indexed from 0.
295 * Example: there are 5 slots in the table, you request slot 0 so it will
298 int get_local_var_table (char **name, char **sig, char **generic_sig,
299 jlong *startloc, jint *length, jint *slot,
302 /* Installs a break instruction at the given code index. Returns
303 the pc_t of the breakpoint or NULL if index is invalid. */
304 pc_t install_break (jlong index);
306 // Gets the instruction at the given index
307 pc_t get_insn (jlong index);
309 /* Writes the given instruction at the given code index. Returns
310 the insn or NULL if index is invalid. */
311 pc_t set_insn (jlong index, pc_t insn);
313 // Is the given location in this method a breakpoint?
314 bool breakpoint_at (jlong index);
316 #ifdef DIRECT_THREADED
317 friend void _Jv_CompileMethod (_Jv_InterpMethod*);
320 friend class _Jv_ClassReader;
321 friend class _Jv_BytecodeVerifier;
322 friend class _Jv_StackTrace;
323 friend class _Jv_InterpreterEngine;
325 #ifdef JV_MARKOBJ_DECL
326 friend JV_MARKOBJ_DECL;
330 class _Jv_InterpClass
332 _Jv_MethodBase **interpreted_methods;
333 _Jv_ushort *field_initializers;
334 jstring source_file_name;
335 _Jv_ClosureList **closures;
337 friend class _Jv_ClassReader;
338 friend class _Jv_InterpMethod;
339 friend class _Jv_StackTrace;
340 friend class _Jv_InterpreterEngine;
342 friend void _Jv_InitField (jobject, jclass, int);
343 #ifdef JV_MARKOBJ_DECL
344 friend JV_MARKOBJ_DECL;
347 friend _Jv_MethodBase ** _Jv_GetFirstMethod (_Jv_InterpClass *klass);
348 friend jstring _Jv_GetInterpClassSourceFile (jclass);
351 extern inline _Jv_MethodBase **
352 _Jv_GetFirstMethod (_Jv_InterpClass *klass)
354 return klass->interpreted_methods;
357 struct _Jv_ResolvedMethod
359 jint stack_item_count;
363 // a resolved method holds the cif in-line, so that _Jv_MarkObj just needs
364 // to mark the resolved method to hold on to the cif. Some memory could be
365 // saved by keeping a cache of cif's, since many will be the same.
367 ffi_type * arg_types[0];
370 class _Jv_JNIMethod : public _Jv_MethodBase
372 // The underlying function. If NULL we have to look for the
376 // This is the CIF used by the JNI function.
379 // These are the argument types used by the JNI function.
380 ffi_type **jni_arg_types;
382 // This function is used when making a JNI call from the interpreter.
383 static void call (ffi_cif *, void *, INTERP_FFI_RAW_TYPE *, void *);
385 void *ncode (jclass);
387 friend class _Jv_ClassReader;
388 friend class _Jv_InterpreterEngine;
390 #ifdef JV_MARKOBJ_DECL
391 friend JV_MARKOBJ_DECL;
395 // FIXME: this is ugly.
396 void set_function (void *f)
402 // The composite call stack as represented by a linked list of frames
406 java::lang::Thread *thread;
410 _Jv_MethodBase *self;
412 _Jv_Method *proxyMethod;
415 //The full list of frames, JNI and interpreted
417 _Jv_FrameType frame_type;
419 _Jv_Frame (_Jv_MethodBase *s, java::lang::Thread *thr, _Jv_FrameType type)
423 next = (_Jv_Frame *) thr->frame;
424 thr->frame = (gnu::gcj::RawData *) this;
430 thread->frame = (gnu::gcj::RawData *) next;
437 for (f = this; f != NULL; f = f->next)
444 // An interpreted frame in the call stack
445 class _Jv_InterpFrame : public _Jv_Frame
449 // Keep the purely interpreted list around so as not to break backtraces
450 _Jv_InterpFrame *next_interp;
458 // Pointer to the actual pc value.
461 //Debug info for local variables.
465 // Object pointer for this frame ("this")
468 _Jv_InterpFrame (void *meth, java::lang::Thread *thr, jclass proxyCls = NULL,
470 _Jv_FrameType frame_type = frame_interpreter)
471 : _Jv_Frame (reinterpret_cast<_Jv_MethodBase *> (meth), thr,
474 next_interp = (_Jv_InterpFrame *) thr->interp_frame;
475 proxyClass = proxyCls;
476 thr->interp_frame = (gnu::gcj::RawData *) this;
483 thread->interp_frame = (gnu::gcj::RawData *) next_interp;
486 jobject get_this_ptr ()
495 // If the PC_PTR is NULL, we are not debugging.
505 // A native frame in the call stack really just a placeholder
506 class _Jv_NativeFrame : public _Jv_Frame
510 _Jv_NativeFrame (_Jv_JNIMethod *s, java::lang::Thread *thr)
511 : _Jv_Frame (s, thr, frame_native)
516 #ifdef DIRECT_THREADED
517 // This class increments and decrements the thread_count field in an
518 // interpreted method. On entry to the interpreter a
519 // ThreadCountAdjuster is created when increments the thread_count in
520 // the current method and uses the next_interp field in the frame to
521 // find the previous method and decrement its thread_count.
522 class ThreadCountAdjuster
525 // A class used to handle the rewrite_insn_mutex while we're
526 // adjusting the thread_count in a method. Unlocking the mutex in a
527 // destructor ensures that it's unlocked even if (for example) a
528 // segfault occurs in the critical section.
534 MutexLock (_Jv_Mutex_t *m)
537 _Jv_MutexLock (mutex);
541 _Jv_MutexUnlock (mutex);
545 _Jv_InterpMethod *method;
546 _Jv_InterpMethod *next_method;
550 ThreadCountAdjuster (_Jv_InterpMethod *m, _Jv_InterpFrame *fr)
552 MutexLock lock (&::_Jv_InterpMethod::rewrite_insn_mutex);
557 _Jv_InterpFrame *next_interp = fr->next_interp;
559 // Record the fact that we're executing this method and that
560 // we're no longer executing the method that called us.
561 method->thread_count++;
563 if (next_interp && next_interp->frame_type == frame_interpreter)
566 = reinterpret_cast<_Jv_InterpMethod *> (next_interp->meth);
567 next_method->thread_count--;
571 ~ThreadCountAdjuster ()
573 MutexLock lock (&::_Jv_InterpMethod::rewrite_insn_mutex);
575 // We're going to return to the method that called us, so bump its
576 // thread_count and decrement our own.
578 method->thread_count--;
581 next_method->thread_count++;
584 #endif // DIRECT_THREADED
586 #endif /* INTERPRETER */
588 #endif /* __JAVA_INTERP_H__ */