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
_Jv_IsInterpretedClass(jclass c)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:
get_method()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
bytecode()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
exceptions()123 _Jv_InterpException * exceptions ()
124 {
125 return (_Jv_InterpException*) (this+1);
126 }
127
size(int exc_count,int code_length)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
_Jv_Defer_Resolution(void * cl,_Jv_Method * meth,void ** address)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 **
_Jv_GetFirstMethod(_Jv_InterpClass * klass)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.
set_function(void * f)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
_Jv_MethodChain_Jv_MethodChain259 _Jv_MethodChain (const _Jv_InterpMethod *s, _Jv_MethodChain **n)
260 {
261 self = s;
262 ptr = n;
263 next = *n;
264 *n = this;
265 }
266
~_Jv_MethodChain_Jv_MethodChain267 ~_Jv_MethodChain ()
268 {
269 *ptr = next;
270 }
271 };
272
273 #endif /* INTERPRETER */
274
275 #endif /* __JAVA_INTERP_H__ */
276