1 /*
2 * Copyright (c) 1997, 2006, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 // SignatureIterators iterate over a Java signature (or parts of it).
26 // (Syntax according to: "The Java Virtual Machine Specification" by
27 // Tim Lindholm & Frank Yellin; section 4.3 Descriptors; p. 89ff.)
28 //
29 // Example: Iterating over ([Lfoo;D)I using
30 // 0123456789
31 //
32 // iterate_parameters() calls: do_array(2, 7); do_double();
33 // iterate_returntype() calls: do_int();
34 // iterate() calls: do_array(2, 7); do_double(); do_int();
35 //
36 // is_return_type() is: false ; false ; true
37 //
38 // NOTE: The new optimizer has an alternate, for-loop based signature
39 // iterator implemented in opto/type.cpp, TypeTuple::make().
40
41 class SignatureIterator: public ResourceObj {
42 protected:
43 symbolHandle _signature; // the signature to iterate over
44 int _index; // the current character index (only valid during iteration)
45 int _parameter_index; // the current parameter index (0 outside iteration phase)
46 BasicType _return_type;
47
48 void expect(char c);
49 void skip_optional_size();
50 int parse_type(); // returns the parameter size in words (0 for void)
51 void check_signature_end();
52
53 public:
54 // Definitions used in generating and iterating the
55 // bit field form of the signature generated by the
56 // Fingerprinter.
57 enum {
58 static_feature_size = 1,
59 result_feature_size = 4,
60 result_feature_mask = 0xF,
61 parameter_feature_size = 4,
62 parameter_feature_mask = 0xF,
63
64 bool_parm = 1,
65 byte_parm = 2,
66 char_parm = 3,
67 short_parm = 4,
68 int_parm = 5,
69 long_parm = 6,
70 float_parm = 7,
71 double_parm = 8,
72 obj_parm = 9,
73 done_parm = 10, // marker for end of parameters
74
75 // max parameters is wordsize minus
76 // The sign bit, termination field, the result and static bit fields
77 max_size_of_parameters = (BitsPerLong-1 -
78 result_feature_size - parameter_feature_size -
79 static_feature_size) / parameter_feature_size
80 };
81
82 // Constructors
83 SignatureIterator(symbolOop signature);
84 SignatureIterator(Thread *thread, symbolOop signature);
85 SignatureIterator(symbolHandle signature);
86
87 // Iteration
88 void dispatch_field(); // dispatches once for field signatures
89 void iterate_parameters(); // iterates over parameters only
90 void iterate_parameters( uint64_t fingerprint );
91 void iterate_returntype(); // iterates over returntype only
92 void iterate(); // iterates over whole signature
93 // Returns the word index of the current parameter;
94 int parameter_index() const { return _parameter_index; }
95 bool is_return_type() const { return parameter_index() < 0; }
96 BasicType get_ret_type() const { return _return_type; }
97
98 // Basic types
99 virtual void do_bool () = 0;
100 virtual void do_char () = 0;
101 virtual void do_float () = 0;
102 virtual void do_double() = 0;
103 virtual void do_byte () = 0;
104 virtual void do_short () = 0;
105 virtual void do_int () = 0;
106 virtual void do_long () = 0;
107 virtual void do_void () = 0;
108
109 // Object types (begin indexes the first character of the entry, end indexes the first character after the entry)
110 virtual void do_object(int begin, int end) = 0;
111 virtual void do_array (int begin, int end) = 0;
112 };
113
114
115 // Specialized SignatureIterators: Used to compute signature specific values.
116
117 class SignatureTypeNames : public SignatureIterator {
118 protected:
119 virtual void type_name(const char* name) = 0;
120
121 void do_bool() { type_name("jboolean"); }
122 void do_char() { type_name("jchar" ); }
123 void do_float() { type_name("jfloat" ); }
124 void do_double() { type_name("jdouble" ); }
125 void do_byte() { type_name("jbyte" ); }
126 void do_short() { type_name("jshort" ); }
127 void do_int() { type_name("jint" ); }
128 void do_long() { type_name("jlong" ); }
129 void do_void() { type_name("void" ); }
130 void do_object(int begin, int end) { type_name("jobject" ); }
131 void do_array (int begin, int end) { type_name("jobject" ); }
132
133 public:
134 SignatureTypeNames(symbolHandle signature) : SignatureIterator(signature) {}
135 };
136
137
138 class SignatureInfo: public SignatureIterator {
139 protected:
140 bool _has_iterated; // need this because iterate cannot be called in constructor (set is virtual!)
141 bool _has_iterated_return;
142 int _size;
143
144 void lazy_iterate_parameters() { if (!_has_iterated) { iterate_parameters(); _has_iterated = true; } }
145 void lazy_iterate_return() { if (!_has_iterated_return) { iterate_returntype(); _has_iterated_return = true; } }
146
147 virtual void set(int size, BasicType type) = 0;
148
149 void do_bool () { set(T_BOOLEAN_size, T_BOOLEAN); }
150 void do_char () { set(T_CHAR_size , T_CHAR ); }
151 void do_float () { set(T_FLOAT_size , T_FLOAT ); }
152 void do_double() { set(T_DOUBLE_size , T_DOUBLE ); }
153 void do_byte () { set(T_BYTE_size , T_BYTE ); }
154 void do_short () { set(T_SHORT_size , T_SHORT ); }
155 void do_int () { set(T_INT_size , T_INT ); }
156 void do_long () { set(T_LONG_size , T_LONG ); }
157 void do_void () { set(T_VOID_size , T_VOID ); }
158 void do_object(int begin, int end) { set(T_OBJECT_size , T_OBJECT ); }
159 void do_array (int begin, int end) { set(T_ARRAY_size , T_ARRAY ); }
160
161 public:
162 SignatureInfo(symbolHandle signature) : SignatureIterator(signature) {
163 _has_iterated = _has_iterated_return = false;
164 _size = 0;
165 _return_type = T_ILLEGAL;
166 }
167
168 };
169
170
171 // Specialized SignatureIterator: Used to compute the argument size.
172
173 class ArgumentSizeComputer: public SignatureInfo {
174 private:
175 void set(int size, BasicType type) { _size += size; }
176 public:
177 ArgumentSizeComputer(symbolHandle signature) : SignatureInfo(signature) {}
178
179 int size() { lazy_iterate_parameters(); return _size; }
180 };
181
182
183 class ArgumentCount: public SignatureInfo {
184 private:
185 void set(int size, BasicType type) { _size ++; }
186 public:
187 ArgumentCount(symbolHandle signature) : SignatureInfo(signature) {}
188
189 int size() { lazy_iterate_parameters(); return _size; }
190 };
191
192
193 // Specialized SignatureIterator: Used to compute the result type.
194
195 class ResultTypeFinder: public SignatureInfo {
196 private:
197 void set(int size, BasicType type) { _return_type = type; }
198 public:
199 BasicType type() { lazy_iterate_return(); return _return_type; }
200
201 ResultTypeFinder(symbolHandle signature) : SignatureInfo(signature) {}
202 };
203
204
205 // Fingerprinter computes a unique ID for a given method. The ID
206 // is a bitvector characterizing the methods signature (incl. the receiver).
207 class Fingerprinter: public SignatureIterator {
208 private:
209 uint64_t _fingerprint;
210 int _shift_count;
211 methodHandle mh;
212
213 public:
214
215 void do_bool() { _fingerprint |= (((uint64_t)bool_parm) << _shift_count); _shift_count += parameter_feature_size; }
216 void do_char() { _fingerprint |= (((uint64_t)char_parm) << _shift_count); _shift_count += parameter_feature_size; }
217 void do_byte() { _fingerprint |= (((uint64_t)byte_parm) << _shift_count); _shift_count += parameter_feature_size; }
218 void do_short() { _fingerprint |= (((uint64_t)short_parm) << _shift_count); _shift_count += parameter_feature_size; }
219 void do_int() { _fingerprint |= (((uint64_t)int_parm) << _shift_count); _shift_count += parameter_feature_size; }
220 void do_long() { _fingerprint |= (((uint64_t)long_parm) << _shift_count); _shift_count += parameter_feature_size; }
221 void do_float() { _fingerprint |= (((uint64_t)float_parm) << _shift_count); _shift_count += parameter_feature_size; }
222 void do_double() { _fingerprint |= (((uint64_t)double_parm) << _shift_count); _shift_count += parameter_feature_size; }
223
224 void do_object(int begin, int end) { _fingerprint |= (((uint64_t)obj_parm) << _shift_count); _shift_count += parameter_feature_size; }
225 void do_array (int begin, int end) { _fingerprint |= (((uint64_t)obj_parm) << _shift_count); _shift_count += parameter_feature_size; }
226
227 void do_void() { ShouldNotReachHere(); }
228
229 Fingerprinter(methodHandle method) : SignatureIterator(method->signature()) {
230 mh = method;
231 _fingerprint = 0;
232 }
233
234 Fingerprinter(Thread *thread, methodHandle method) : SignatureIterator(thread, method->signature()) {
235 mh = method;
236 _fingerprint = 0;
237 }
238
239 uint64_t fingerprint() {
240 // See if we fingerprinted this method already
241 if (mh->constMethod()->fingerprint() != CONST64(0)) {
242 return mh->constMethod()->fingerprint();
243 }
244
245 if (mh->size_of_parameters() > max_size_of_parameters ) {
246 _fingerprint = UCONST64(-1);
247 mh->constMethod()->set_fingerprint(_fingerprint);
248 return _fingerprint;
249 }
250
251 assert( (int)mh->result_type() <= (int)result_feature_mask, "bad result type");
252 _fingerprint = mh->result_type();
253 _fingerprint <<= static_feature_size;
254 if (mh->is_static()) _fingerprint |= 1;
255 _shift_count = result_feature_size + static_feature_size;
256 iterate_parameters();
257 _fingerprint |= ((uint64_t)done_parm) << _shift_count;// mark end of sig
258 mh->constMethod()->set_fingerprint(_fingerprint);
259 return _fingerprint;
260 }
261 };
262
263
264 // Specialized SignatureIterator: Used for native call purposes
265
266 class NativeSignatureIterator: public SignatureIterator {
267 private:
268 methodHandle _method;
269 // We need separate JNI and Java offset values because in 64 bit mode,
270 // the argument offsets are not in sync with the Java stack.
271 // For example a long takes up 1 "C" stack entry but 2 Java stack entries.
272 int _offset; // The java stack offset
273 int _prepended; // number of prepended JNI parameters (1 JNIEnv, plus 1 mirror if static)
274 int _jni_offset; // the current parameter offset, starting with 0
275
276 void do_bool () { pass_int(); _jni_offset++; _offset++; }
277 void do_char () { pass_int(); _jni_offset++; _offset++; }
278 void do_float () { pass_float(); _jni_offset++; _offset++; }
279 #ifdef _LP64
280 void do_double() { pass_double(); _jni_offset++; _offset += 2; }
281 #else
282 void do_double() { pass_double(); _jni_offset += 2; _offset += 2; }
283 #endif
284 void do_byte () { pass_int(); _jni_offset++; _offset++; }
285 void do_short () { pass_int(); _jni_offset++; _offset++; }
286 void do_int () { pass_int(); _jni_offset++; _offset++; }
287 #ifdef _LP64
288 void do_long () { pass_long(); _jni_offset++; _offset += 2; }
289 #else
290 void do_long () { pass_long(); _jni_offset += 2; _offset += 2; }
291 #endif
292 void do_void () { ShouldNotReachHere(); }
293 void do_object(int begin, int end) { pass_object(); _jni_offset++; _offset++; }
294 void do_array (int begin, int end) { pass_object(); _jni_offset++; _offset++; }
295
296 public:
297 methodHandle method() const { return _method; }
298 int offset() const { return _offset; }
299 int jni_offset() const { return _jni_offset + _prepended; }
300 // int java_offset() const { return method()->size_of_parameters() - _offset - 1; }
301 bool is_static() const { return method()->is_static(); }
302 virtual void pass_int() = 0;
303 virtual void pass_long() = 0;
304 virtual void pass_object() = 0;
305 virtual void pass_float() = 0;
306 #ifdef _LP64
307 virtual void pass_double() = 0;
308 #else
309 virtual void pass_double() { pass_long(); } // may be same as long
310 #endif
311
312 NativeSignatureIterator(methodHandle method) : SignatureIterator(method->signature()) {
313 _method = method;
314 _offset = 0;
315 _jni_offset = 0;
316
317 const int JNIEnv_words = 1;
318 const int mirror_words = 1;
319 _prepended = !is_static() ? JNIEnv_words : JNIEnv_words + mirror_words;
320 }
321
322 // iterate() calles the 2 virtual methods according to the following invocation syntax:
323 //
324 // {pass_int | pass_long | pass_object}
325 //
326 // Arguments are handled from left to right (receiver first, if any).
327 // The offset() values refer to the Java stack offsets but are 0 based and increasing.
328 // The java_offset() values count down to 0, and refer to the Java TOS.
329 // The jni_offset() values increase from 1 or 2, and refer to C arguments.
330
331 void iterate() { iterate(Fingerprinter(method()).fingerprint());
332 }
333
334
335 // Optimized path if we have the bitvector form of signature
336 void iterate( uint64_t fingerprint ) {
337
338 if (!is_static()) {
339 // handle receiver (not handled by iterate because not in signature)
340 pass_object(); _jni_offset++; _offset++;
341 }
342
343 SignatureIterator::iterate_parameters( fingerprint );
344 }
345 };
346
347
348 // Handy stream for iterating over signature
349
350 class SignatureStream : public StackObj {
351 private:
352 symbolHandle _signature;
353 int _begin;
354 int _end;
355 BasicType _type;
356 bool _at_return_type;
357
358 public:
359 bool at_return_type() const { return _at_return_type; }
360 bool is_done() const;
361 void next_non_primitive(int t);
362 void next() {
363 symbolOop sig = _signature();
364 int len = sig->utf8_length();
365 if (_end >= len) {
366 _end = len + 1;
367 return;
368 }
369
370 _begin = _end;
371 int t = sig->byte_at(_begin);
372 switch (t) {
373 case 'B': _type = T_BYTE; break;
374 case 'C': _type = T_CHAR; break;
375 case 'D': _type = T_DOUBLE; break;
376 case 'F': _type = T_FLOAT; break;
377 case 'I': _type = T_INT; break;
378 case 'J': _type = T_LONG; break;
379 case 'S': _type = T_SHORT; break;
380 case 'Z': _type = T_BOOLEAN; break;
381 case 'V': _type = T_VOID; break;
382 default : next_non_primitive(t);
383 return;
384 }
385 _end++;
386 }
387
388 SignatureStream(symbolHandle signature,
389 bool is_method = true) :
390 _signature(signature), _at_return_type(false) {
391 _begin = _end = (is_method ? 1 : 0); // skip first '(' in method signatures
392 next();
393 }
394
395 bool is_object() const; // True if this argument is an object
396 bool is_array() const; // True if this argument is an array
397 BasicType type() const { return _type; }
398 symbolOop as_symbol(TRAPS);
399 enum FailureMode { ReturnNull, CNFException, NCDFError };
400 klassOop as_klass(Handle class_loader, Handle protection_domain, FailureMode failure_mode, TRAPS);
401 oop as_java_mirror(Handle class_loader, Handle protection_domain, FailureMode failure_mode, TRAPS);
402
403 // return same as_symbol except allocation of new symbols is avoided.
404 symbolOop as_symbol_or_null();
405 };
406
407 class SignatureVerifier : public StackObj {
408 public:
409 // Returns true if the symbol is valid method or type signature
410 static bool is_valid_signature(symbolHandle sig);
411
412 static bool is_valid_method_signature(symbolHandle sig);
413 static bool is_valid_type_signature(symbolHandle sig);
414 private:
415
416 static ssize_t is_valid_type(const char*, ssize_t);
417 static bool invalid_name_char(char);
418 };