1 /*
2 * Copyright (c) 1997, 2019, 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.
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23 */
24
25 #ifndef SHARE_RUNTIME_SIGNATURE_HPP
26 #define SHARE_RUNTIME_SIGNATURE_HPP
27
28 #include "classfile/symbolTable.hpp"
29 #include "memory/allocation.hpp"
30 #include "oops/method.hpp"
31
32 // SignatureIterators iterate over a Java signature (or parts of it).
33 // (Syntax according to: "The Java Virtual Machine Specification" by
34 // Tim Lindholm & Frank Yellin; section 4.3 Descriptors; p. 89ff.)
35 //
36 // Example: Iterating over ([Lfoo;D)I using
37 // 0123456789
38 //
39 // iterate_parameters() calls: do_array(2, 7); do_double();
40 // iterate_returntype() calls: do_int();
41 // iterate() calls: do_array(2, 7); do_double(); do_int();
42 //
43 // is_return_type() is: false ; false ; true
44 //
45 // NOTE: The new optimizer has an alternate, for-loop based signature
46 // iterator implemented in opto/type.cpp, TypeTuple::make().
47
48 class SignatureIterator: public ResourceObj {
49 protected:
50 Symbol* _signature; // the signature to iterate over
51 int _index; // the current character index (only valid during iteration)
52 int _parameter_index; // the current parameter index (0 outside iteration phase)
53 BasicType _return_type;
54
55 void expect(char c);
56 int parse_type(); // returns the parameter size in words (0 for void)
57 void check_signature_end();
58
59 public:
60 // Definitions used in generating and iterating the
61 // bit field form of the signature generated by the
62 // Fingerprinter.
63 enum {
64 static_feature_size = 1,
65 is_static_bit = 1,
66
67 result_feature_size = 4,
68 result_feature_mask = 0xF,
69 parameter_feature_size = 4,
70 parameter_feature_mask = 0xF,
71
72 bool_parm = 1,
73 byte_parm = 2,
74 char_parm = 3,
75 short_parm = 4,
76 int_parm = 5,
77 long_parm = 6,
78 float_parm = 7,
79 double_parm = 8,
80 obj_parm = 9,
81 done_parm = 10, // marker for end of parameters
82
83 // max parameters is wordsize minus
84 // The sign bit, termination field, the result and static bit fields
85 max_size_of_parameters = (BitsPerLong-1 -
86 result_feature_size - parameter_feature_size -
87 static_feature_size) / parameter_feature_size
88 };
89
90 // Constructors
91 SignatureIterator(Symbol* signature);
92
93 // Iteration
94 void dispatch_field(); // dispatches once for field signatures
95 void iterate_parameters(); // iterates over parameters only
96 void iterate_parameters( uint64_t fingerprint );
97 void iterate_returntype(); // iterates over returntype only
98 void iterate(); // iterates over whole signature
99 // Returns the word index of the current parameter;
100 int parameter_index() const { return _parameter_index; }
101 bool is_return_type() const { return parameter_index() < 0; }
102 BasicType get_ret_type() const { return _return_type; }
103
104 // Basic types
105 virtual void do_bool () = 0;
106 virtual void do_char () = 0;
107 virtual void do_float () = 0;
108 virtual void do_double() = 0;
109 virtual void do_byte () = 0;
110 virtual void do_short () = 0;
111 virtual void do_int () = 0;
112 virtual void do_long () = 0;
113 virtual void do_void () = 0;
114
115 // Object types (begin indexes the first character of the entry, end indexes the first character after the entry)
116 virtual void do_object(int begin, int end) = 0;
117 virtual void do_valuetype(int begin, int end) = 0;
118 virtual void do_array (int begin, int end) = 0;
119
120 static bool is_static(uint64_t fingerprint) {
121 assert(fingerprint != (uint64_t)CONST64(-1), "invalid fingerprint");
122 return fingerprint & is_static_bit;
123 }
124 static BasicType return_type(uint64_t fingerprint) {
125 assert(fingerprint != (uint64_t)CONST64(-1), "invalid fingerprint");
126 return (BasicType) ((fingerprint >> static_feature_size) & result_feature_mask);
127 }
128 };
129
130
131 // Specialized SignatureIterators: Used to compute signature specific values.
132
133 class SignatureTypeNames : public SignatureIterator {
134 protected:
135 virtual void type_name(const char* name) = 0;
136
137 void do_bool() { type_name("jboolean"); }
138 void do_char() { type_name("jchar" ); }
139 void do_float() { type_name("jfloat" ); }
140 void do_double() { type_name("jdouble" ); }
141 void do_byte() { type_name("jbyte" ); }
142 void do_short() { type_name("jshort" ); }
143 void do_int() { type_name("jint" ); }
144 void do_long() { type_name("jlong" ); }
145 void do_void() { type_name("void" ); }
146 void do_object(int begin, int end) { type_name("jobject" ); }
147 void do_valuetype(int begin, int end) { type_name("jobject"); }
148 void do_array (int begin, int end) { type_name("jobject" ); }
149
150 public:
151 SignatureTypeNames(Symbol* signature) : SignatureIterator(signature) {}
152 };
153
154
155 class SignatureInfo: public SignatureIterator {
156 protected:
157 bool _has_iterated; // need this because iterate cannot be called in constructor (set is virtual!)
158 bool _has_iterated_return;
159 int _size;
160
161 void lazy_iterate_parameters() { if (!_has_iterated) { iterate_parameters(); _has_iterated = true; } }
162 void lazy_iterate_return() { if (!_has_iterated_return) { iterate_returntype(); _has_iterated_return = true; } }
163
164 virtual void set(int size, BasicType type) = 0;
165
166 void do_bool () { set(T_BOOLEAN_size, T_BOOLEAN); }
167 void do_char () { set(T_CHAR_size , T_CHAR ); }
168 void do_float () { set(T_FLOAT_size , T_FLOAT ); }
169 void do_double() { set(T_DOUBLE_size , T_DOUBLE ); }
170 void do_byte () { set(T_BYTE_size , T_BYTE ); }
171 void do_short () { set(T_SHORT_size , T_SHORT ); }
172 void do_int () { set(T_INT_size , T_INT ); }
173 void do_long () { set(T_LONG_size , T_LONG ); }
174 void do_void () { set(T_VOID_size , T_VOID ); }
175 void do_object(int begin, int end) { set(T_OBJECT_size , T_OBJECT ); }
176 void do_valuetype(int begin, int end) { set(T_VALUETYPE_size, T_VALUETYPE ); }
177 void do_array (int begin, int end) { set(T_ARRAY_size , T_ARRAY ); }
178
179 public:
180 SignatureInfo(Symbol* signature) : SignatureIterator(signature) {
181 _has_iterated = _has_iterated_return = false;
182 _size = 0;
183 _return_type = T_ILLEGAL;
184 }
185
186 };
187
188
189 // Specialized SignatureIterator: Used to compute the argument size.
190
191 class ArgumentSizeComputer: public SignatureInfo {
192 private:
193 void set(int size, BasicType type) { _size += size; }
194 public:
195 ArgumentSizeComputer(Symbol* signature) : SignatureInfo(signature) {}
196
197 int size() { lazy_iterate_parameters(); return _size; }
198 };
199
200
201 class ArgumentCount: public SignatureInfo {
202 private:
203 void set(int size, BasicType type) { _size ++; }
204 public:
205 ArgumentCount(Symbol* signature) : SignatureInfo(signature) {}
206
207 int size() { lazy_iterate_parameters(); return _size; }
208 };
209
210
211 // Specialized SignatureIterator: Used to compute the result type.
212
213 class ResultTypeFinder: public SignatureInfo {
214 private:
215 void set(int size, BasicType type) { _return_type = type; }
216 public:
217 BasicType type() { lazy_iterate_return(); return _return_type; }
218
219 ResultTypeFinder(Symbol* signature) : SignatureInfo(signature) {}
220 };
221
222
223 // Fingerprinter computes a unique ID for a given method. The ID
224 // is a bitvector characterizing the methods signature (incl. the receiver).
225 class Fingerprinter: public SignatureIterator {
226 private:
227 uint64_t _fingerprint;
228 int _shift_count;
229 methodHandle mh;
230
231 public:
232
233 void do_bool() { _fingerprint |= (((uint64_t)bool_parm) << _shift_count); _shift_count += parameter_feature_size; }
234 void do_char() { _fingerprint |= (((uint64_t)char_parm) << _shift_count); _shift_count += parameter_feature_size; }
235 void do_byte() { _fingerprint |= (((uint64_t)byte_parm) << _shift_count); _shift_count += parameter_feature_size; }
236 void do_short() { _fingerprint |= (((uint64_t)short_parm) << _shift_count); _shift_count += parameter_feature_size; }
237 void do_int() { _fingerprint |= (((uint64_t)int_parm) << _shift_count); _shift_count += parameter_feature_size; }
238 void do_long() { _fingerprint |= (((uint64_t)long_parm) << _shift_count); _shift_count += parameter_feature_size; }
239 void do_float() { _fingerprint |= (((uint64_t)float_parm) << _shift_count); _shift_count += parameter_feature_size; }
240 void do_double() { _fingerprint |= (((uint64_t)double_parm) << _shift_count); _shift_count += parameter_feature_size; }
241
242 void do_object(int begin, int end) { _fingerprint |= (((uint64_t)obj_parm) << _shift_count); _shift_count += parameter_feature_size; }
243 void do_valuetype(int begin, int end) { _fingerprint |= (((uint64_t)obj_parm) << _shift_count); _shift_count += parameter_feature_size; }
244 void do_array (int begin, int end) { _fingerprint |= (((uint64_t)obj_parm) << _shift_count); _shift_count += parameter_feature_size; }
245
246 void do_void() { ShouldNotReachHere(); }
247
248 Fingerprinter(const methodHandle& method) : SignatureIterator(method->signature()) {
249 mh = method;
250 _fingerprint = 0;
251 }
252
253 uint64_t fingerprint() {
254 // See if we fingerprinted this method already
255 if (mh->constMethod()->fingerprint() != CONST64(0)) {
256 return mh->constMethod()->fingerprint();
257 }
258
259 if (mh->size_of_parameters() > max_size_of_parameters ) {
260 _fingerprint = (uint64_t)CONST64(-1);
261 mh->constMethod()->set_fingerprint(_fingerprint);
262 return _fingerprint;
263 }
264
265 assert( (int)mh->result_type() <= (int)result_feature_mask, "bad result type");
266 _fingerprint = mh->result_type();
267 _fingerprint <<= static_feature_size;
268 if (mh->is_static()) _fingerprint |= 1;
269 _shift_count = result_feature_size + static_feature_size;
270 iterate_parameters();
271 _fingerprint |= ((uint64_t)done_parm) << _shift_count;// mark end of sig
272 mh->constMethod()->set_fingerprint(_fingerprint);
273 return _fingerprint;
274 }
275 };
276
277
278 // Specialized SignatureIterator: Used for native call purposes
279
280 class NativeSignatureIterator: public SignatureIterator {
281 private:
282 methodHandle _method;
283 // We need separate JNI and Java offset values because in 64 bit mode,
284 // the argument offsets are not in sync with the Java stack.
285 // For example a long takes up 1 "C" stack entry but 2 Java stack entries.
286 int _offset; // The java stack offset
287 int _prepended; // number of prepended JNI parameters (1 JNIEnv, plus 1 mirror if static)
288 int _jni_offset; // the current parameter offset, starting with 0
289
290 void do_bool () { pass_int(); _jni_offset++; _offset++; }
291 void do_char () { pass_int(); _jni_offset++; _offset++; }
292 void do_float () { pass_float(); _jni_offset++; _offset++; }
293 #ifdef _LP64
294 void do_double() { pass_double(); _jni_offset++; _offset += 2; }
295 #else
296 void do_double() { pass_double(); _jni_offset += 2; _offset += 2; }
297 #endif
298 void do_byte () { pass_int(); _jni_offset++; _offset++; }
299 void do_short () { pass_int(); _jni_offset++; _offset++; }
300 void do_int () { pass_int(); _jni_offset++; _offset++; }
301 #ifdef _LP64
302 void do_long () { pass_long(); _jni_offset++; _offset += 2; }
303 #else
304 void do_long () { pass_long(); _jni_offset += 2; _offset += 2; }
305 #endif
306 void do_void () { ShouldNotReachHere(); }
307 void do_object(int begin, int end) { pass_object(); _jni_offset++; _offset++; }
308 void do_array (int begin, int end) { pass_object(); _jni_offset++; _offset++; }
309 void do_valuetype(int begin, int end){ pass_valuetype(); _jni_offset++; _offset++; }
310
311 public:
312 methodHandle method() const { return _method; }
313 int offset() const { return _offset; }
314 int jni_offset() const { return _jni_offset + _prepended; }
315 // int java_offset() const { return method()->size_of_parameters() - _offset - 1; }
316 bool is_static() const { return method()->is_static(); }
317 virtual void pass_int() = 0;
318 virtual void pass_long() = 0;
319 virtual void pass_object() = 0;
320 virtual void pass_valuetype() = 0;
321 virtual void pass_float() = 0;
322 #ifdef _LP64
323 virtual void pass_double() = 0;
324 #else
325 virtual void pass_double() { pass_long(); } // may be same as long
326 #endif
327
328 NativeSignatureIterator(const methodHandle& method) : SignatureIterator(method->signature()) {
329 _method = method;
330 _offset = 0;
331 _jni_offset = 0;
332
333 const int JNIEnv_words = 1;
334 const int mirror_words = 1;
335 _prepended = !is_static() ? JNIEnv_words : JNIEnv_words + mirror_words;
336 }
337
338 // iterate() calles the 2 virtual methods according to the following invocation syntax:
339 //
340 // {pass_int | pass_long | pass_object}
341 //
342 // Arguments are handled from left to right (receiver first, if any).
343 // The offset() values refer to the Java stack offsets but are 0 based and increasing.
344 // The java_offset() values count down to 0, and refer to the Java TOS.
345 // The jni_offset() values increase from 1 or 2, and refer to C arguments.
346
347 void iterate() { iterate(Fingerprinter(method()).fingerprint());
348 }
349
350
351 // Optimized path if we have the bitvector form of signature
352 void iterate( uint64_t fingerprint ) {
353
354 if (!is_static()) {
355 // handle receiver (not handled by iterate because not in signature)
356 pass_object(); _jni_offset++; _offset++;
357 }
358
359 SignatureIterator::iterate_parameters( fingerprint );
360 }
361 };
362
363
364 // Handy stream for iterating over signature
365
366 class SignatureStream : public StackObj {
367 private:
368 Symbol* _signature;
369 int _begin;
370 int _end;
371 BasicType _type;
372 bool _at_return_type;
373 GrowableArray<Symbol*>* _names; // symbols created while parsing signature
374
375 public:
376 bool at_return_type() const { return _at_return_type; }
377 bool is_done() const;
378 void next_non_primitive(int t);
379 void next() {
380 Symbol* sig = _signature;
381 int len = sig->utf8_length();
382 if (_end >= len) {
383 _end = len + 1;
384 return;
385 }
386
387 _begin = _end;
388 int t = sig->char_at(_begin);
389 switch (t) {
390 case 'B': _type = T_BYTE; break;
391 case 'C': _type = T_CHAR; break;
392 case 'D': _type = T_DOUBLE; break;
393 case 'F': _type = T_FLOAT; break;
394 case 'I': _type = T_INT; break;
395 case 'J': _type = T_LONG; break;
396 case 'S': _type = T_SHORT; break;
397 case 'Z': _type = T_BOOLEAN; break;
398 case 'V': _type = T_VOID; break;
399 default : next_non_primitive(t);
400 return;
401 }
402 _end++;
403 }
404
405 SignatureStream(Symbol* signature, bool is_method = true);
406 ~SignatureStream();
407
408 bool is_object() const; // True if this argument is an object
409 bool is_array() const; // True if this argument is an array
410 BasicType type() const { return _type; }
411 Symbol* as_symbol(TRAPS);
412 enum FailureMode { ReturnNull, CNFException, NCDFError };
413 Klass* as_klass(Handle class_loader, Handle protection_domain, FailureMode failure_mode, TRAPS);
414 oop as_java_mirror(Handle class_loader, Handle protection_domain, FailureMode failure_mode, TRAPS);
415 const u1* raw_bytes() { return _signature->bytes() + _begin; }
416 int raw_length() { return _end - _begin; }
417
418 // return same as_symbol except allocation of new symbols is avoided.
419 Symbol* as_symbol_or_null();
420
421 // count the number of references in the signature
422 int reference_parameter_count();
423 };
424
425 class SignatureVerifier : public StackObj {
426 public:
427 // Returns true if the symbol is valid method or type signature
428 static bool is_valid_signature(Symbol* sig);
429
430 static bool is_valid_method_signature(Symbol* sig);
431 static bool is_valid_type_signature(Symbol* sig);
432 private:
433
434 static ssize_t is_valid_type(const char*, ssize_t);
435 static bool invalid_name_char(char);
436 };
437
438 class SigEntryFilter;
439 typedef GrowableArrayFilterIterator<SigEntry, SigEntryFilter> ExtendedSignature;
440
441 // Used for adapter generation. One SigEntry is used per element of
442 // the signature of the method. Value type arguments are treated
443 // specially. See comment for ValueKlass::collect_fields().
444 class SigEntry {
445 public:
446 BasicType _bt;
447 int _offset;
448
449 enum { ReservedOffset = -2 }; // Special offset to mark the reserved entry
450
451 SigEntry()
452 : _bt(T_ILLEGAL), _offset(-1) {
453 }
454 SigEntry(BasicType bt, int offset)
455 : _bt(bt), _offset(offset) {}
456
457 SigEntry(BasicType bt)
458 : _bt(bt), _offset(-1) {}
459
460 static int compare(SigEntry* e1, SigEntry* e2) {
461 if (e1->_offset != e2->_offset) {
462 return e1->_offset - e2->_offset;
463 }
464 assert((e1->_bt == T_LONG && (e2->_bt == T_LONG || e2->_bt == T_VOID)) ||
465 (e1->_bt == T_DOUBLE && (e2->_bt == T_DOUBLE || e2->_bt == T_VOID)) ||
466 e1->_bt == T_VALUETYPE || e2->_bt == T_VALUETYPE || e1->_bt == T_VOID || e2->_bt == T_VOID, "bad bt");
467 if (e1->_bt == e2->_bt) {
468 assert(e1->_bt == T_VALUETYPE || e1->_bt == T_VOID, "only ones with duplicate offsets");
469 return 0;
470 }
471 if (e1->_bt == T_VOID ||
472 e2->_bt == T_VALUETYPE) {
473 return 1;
474 }
475 if (e1->_bt == T_VALUETYPE ||
476 e2->_bt == T_VOID) {
477 return -1;
478 }
479 ShouldNotReachHere();
480 return 0;
481 }
482 static void add_entry(GrowableArray<SigEntry>* sig, BasicType bt, int offset = -1);
483 static void insert_reserved_entry(GrowableArray<SigEntry>* sig, int i, BasicType bt);
484 static bool is_reserved_entry(const GrowableArray<SigEntry>* sig, int i);
485 static bool skip_value_delimiters(const GrowableArray<SigEntry>* sig, int i);
486 static int fill_sig_bt(const GrowableArray<SigEntry>* sig, BasicType* sig_bt);
487 static TempNewSymbol create_symbol(const GrowableArray<SigEntry>* sig);
488
489 static bool next_is_reserved(ExtendedSignature& sig, BasicType& bt, bool can_be_void = false);
490 };
491
492 class SigEntryFilter {
493 public:
494 bool operator()(const SigEntry& entry) { return entry._bt != T_VALUETYPE && entry._bt != T_VOID; }
495 };
496
497 #endif // SHARE_RUNTIME_SIGNATURE_HPP