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. 22 * 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 iterate_parameters(); // iterates over parameters only 95 void iterate_parameters( uint64_t fingerprint ); 96 void iterate_returntype(); // iterates over returntype only 97 void iterate(); // iterates over whole signature 98 // Returns the word index of the current parameter; 99 int parameter_index() const { return _parameter_index; } 100 bool is_return_type() const { return parameter_index() < 0; } 101 BasicType get_ret_type() const { return _return_type; } 102 103 // Basic types 104 virtual void do_bool () = 0; 105 virtual void do_char () = 0; 106 virtual void do_float () = 0; 107 virtual void do_double() = 0; 108 virtual void do_byte () = 0; 109 virtual void do_short () = 0; 110 virtual void do_int () = 0; 111 virtual void do_long () = 0; 112 virtual void do_void () = 0; 113 114 // Object types (begin indexes the first character of the entry, end indexes the first character after the entry) 115 virtual void do_object(int begin, int end) = 0; 116 virtual void do_valuetype(int begin, int end) = 0; 117 virtual void do_array (int begin, int end) = 0; 118 119 static bool is_static(uint64_t fingerprint) { 120 assert(fingerprint != (uint64_t)CONST64(-1), "invalid fingerprint"); 121 return fingerprint & is_static_bit; 122 } 123 static BasicType return_type(uint64_t fingerprint) { 124 assert(fingerprint != (uint64_t)CONST64(-1), "invalid fingerprint"); 125 return (BasicType) ((fingerprint >> static_feature_size) & result_feature_mask); 126 } 127 }; 128 129 130 // Specialized SignatureIterators: Used to compute signature specific values. 131 132 class SignatureTypeNames : public SignatureIterator { 133 protected: 134 virtual void type_name(const char* name) = 0; 135 136 void do_bool() { type_name("jboolean"); } 137 void do_char() { type_name("jchar" ); } 138 void do_float() { type_name("jfloat" ); } 139 void do_double() { type_name("jdouble" ); } 140 void do_byte() { type_name("jbyte" ); } 141 void do_short() { type_name("jshort" ); } 142 void do_int() { type_name("jint" ); } 143 void do_long() { type_name("jlong" ); } 144 void do_void() { type_name("void" ); } 145 void do_object(int begin, int end) { type_name("jobject" ); } 146 void do_valuetype(int begin, int end) { type_name("jobject"); } 147 void do_array (int begin, int end) { type_name("jobject" ); } 148 149 public: 150 SignatureTypeNames(Symbol* signature) : SignatureIterator(signature) {} 151 }; 152 153 154 class SignatureInfo: public SignatureIterator { 155 protected: 156 bool _has_iterated; // need this because iterate cannot be called in constructor (set is virtual!) 157 bool _has_iterated_return; 158 int _size; 159 160 void lazy_iterate_parameters() { if (!_has_iterated) { iterate_parameters(); _has_iterated = true; } } 161 void lazy_iterate_return() { if (!_has_iterated_return) { iterate_returntype(); _has_iterated_return = true; } } 162 163 virtual void set(int size, BasicType type) = 0; 164 165 void do_bool () { set(T_BOOLEAN_size, T_BOOLEAN); } 166 void do_char () { set(T_CHAR_size , T_CHAR ); } 167 void do_float () { set(T_FLOAT_size , T_FLOAT ); } 168 void do_double() { set(T_DOUBLE_size , T_DOUBLE ); } 169 void do_byte () { set(T_BYTE_size , T_BYTE ); } 170 void do_short () { set(T_SHORT_size , T_SHORT ); } 171 void do_int () { set(T_INT_size , T_INT ); } 172 void do_long () { set(T_LONG_size , T_LONG ); } 173 void do_void () { set(T_VOID_size , T_VOID ); } 174 void do_object(int begin, int end) { set(T_OBJECT_size , T_OBJECT ); } 175 void do_valuetype(int begin, int end) { set(T_VALUETYPE_size, T_VALUETYPE ); } 176 void do_array (int begin, int end) { set(T_ARRAY_size , T_ARRAY ); } 177 178 public: 179 SignatureInfo(Symbol* signature) : SignatureIterator(signature) { 180 _has_iterated = _has_iterated_return = false; 181 _size = 0; 182 _return_type = T_ILLEGAL; 183 } 184 185 }; 186 187 188 // Specialized SignatureIterator: Used to compute the argument size. 189 190 class ArgumentSizeComputer: public SignatureInfo { 191 private: 192 void set(int size, BasicType type) { _size += size; } 193 public: 194 ArgumentSizeComputer(Symbol* signature) : SignatureInfo(signature) {} 195 196 int size() { lazy_iterate_parameters(); return _size; } 197 }; 198 199 200 class ArgumentCount: public SignatureInfo { 201 private: 202 void set(int size, BasicType type) { _size ++; } 203 public: 204 ArgumentCount(Symbol* signature) : SignatureInfo(signature) {} 205 206 int size() { lazy_iterate_parameters(); return _size; } 207 }; 208 209 210 // Specialized SignatureIterator: Used to compute the result type. 211 212 class ResultTypeFinder: public SignatureInfo { 213 private: 214 void set(int size, BasicType type) { _return_type = type; } 215 public: 216 BasicType type() { lazy_iterate_return(); return _return_type; } 217 218 ResultTypeFinder(Symbol* signature) : SignatureInfo(signature) {} 219 }; 220 221 222 // Fingerprinter computes a unique ID for a given method. The ID 223 // is a bitvector characterizing the methods signature (incl. the receiver). 224 class Fingerprinter: public SignatureIterator { 225 private: 226 uint64_t _fingerprint; 227 int _shift_count; 228 methodHandle mh; 229 230 public: 231 232 void do_bool() { _fingerprint |= (((uint64_t)bool_parm) << _shift_count); _shift_count += parameter_feature_size; } 233 void do_char() { _fingerprint |= (((uint64_t)char_parm) << _shift_count); _shift_count += parameter_feature_size; } 234 void do_byte() { _fingerprint |= (((uint64_t)byte_parm) << _shift_count); _shift_count += parameter_feature_size; } 235 void do_short() { _fingerprint |= (((uint64_t)short_parm) << _shift_count); _shift_count += parameter_feature_size; } 236 void do_int() { _fingerprint |= (((uint64_t)int_parm) << _shift_count); _shift_count += parameter_feature_size; } 237 void do_long() { _fingerprint |= (((uint64_t)long_parm) << _shift_count); _shift_count += parameter_feature_size; } 238 void do_float() { _fingerprint |= (((uint64_t)float_parm) << _shift_count); _shift_count += parameter_feature_size; } 239 void do_double() { _fingerprint |= (((uint64_t)double_parm) << _shift_count); _shift_count += parameter_feature_size; } 240 241 void do_object(int begin, int end) { _fingerprint |= (((uint64_t)obj_parm) << _shift_count); _shift_count += parameter_feature_size; } 242 void do_valuetype(int begin, int end) { _fingerprint |= (((uint64_t)obj_parm) << _shift_count); _shift_count += parameter_feature_size; } 243 void do_array (int begin, int end) { _fingerprint |= (((uint64_t)obj_parm) << _shift_count); _shift_count += parameter_feature_size; } 244 245 void do_void() { ShouldNotReachHere(); } 246 247 Fingerprinter(const methodHandle& method) : SignatureIterator(method->signature()) { 248 mh = method; 249 _fingerprint = 0; 250 } 251 252 uint64_t fingerprint() { 253 // See if we fingerprinted this method already 254 if (mh->constMethod()->fingerprint() != CONST64(0)) { 255 return mh->constMethod()->fingerprint(); 256 } 257 258 if (mh->size_of_parameters() > max_size_of_parameters ) { 259 _fingerprint = (uint64_t)CONST64(-1); 260 mh->constMethod()->set_fingerprint(_fingerprint); 261 return _fingerprint; 262 } 263 264 assert( (int)mh->result_type() <= (int)result_feature_mask, "bad result type"); 265 _fingerprint = mh->result_type(); 266 _fingerprint <<= static_feature_size; 267 if (mh->is_static()) _fingerprint |= 1; 268 _shift_count = result_feature_size + static_feature_size; 269 iterate_parameters(); 270 _fingerprint |= ((uint64_t)done_parm) << _shift_count;// mark end of sig 271 mh->constMethod()->set_fingerprint(_fingerprint); 272 return _fingerprint; 273 } 274 }; 275 276 277 // Specialized SignatureIterator: Used for native call purposes 278 279 class NativeSignatureIterator: public SignatureIterator { 280 private: 281 methodHandle _method; 282 // We need separate JNI and Java offset values because in 64 bit mode, 283 // the argument offsets are not in sync with the Java stack. 284 // For example a long takes up 1 "C" stack entry but 2 Java stack entries. 285 int _offset; // The java stack offset 286 int _prepended; // number of prepended JNI parameters (1 JNIEnv, plus 1 mirror if static) 287 int _jni_offset; // the current parameter offset, starting with 0 288 289 void do_bool () { pass_int(); _jni_offset++; _offset++; } 290 void do_char () { pass_int(); _jni_offset++; _offset++; } 291 void do_float () { pass_float(); _jni_offset++; _offset++; } 292 #ifdef _LP64 293 void do_double() { pass_double(); _jni_offset++; _offset += 2; } 294 #else 295 void do_double() { pass_double(); _jni_offset += 2; _offset += 2; } 296 #endif 297 void do_byte () { pass_int(); _jni_offset++; _offset++; } 298 void do_short () { pass_int(); _jni_offset++; _offset++; } 299 void do_int () { pass_int(); _jni_offset++; _offset++; } 300 #ifdef _LP64 301 void do_long () { pass_long(); _jni_offset++; _offset += 2; } 302 #else 303 void do_long () { pass_long(); _jni_offset += 2; _offset += 2; } 304 #endif 305 void do_void () { ShouldNotReachHere(); } 306 void do_object(int begin, int end) { pass_object(); _jni_offset++; _offset++; } 307 void do_array (int begin, int end) { pass_object(); _jni_offset++; _offset++; } 308 void do_valuetype(int begin, int end){ pass_valuetype(); _jni_offset++; _offset++; } 309 310 public: 311 methodHandle method() const { return _method; } 312 int offset() const { return _offset; } 313 int jni_offset() const { return _jni_offset + _prepended; } 314 // int java_offset() const { return method()->size_of_parameters() - _offset - 1; } 315 bool is_static() const { return method()->is_static(); } 316 virtual void pass_int() = 0; 317 virtual void pass_long() = 0; 318 virtual void pass_object() = 0; 319 virtual void pass_valuetype() = 0; 320 virtual void pass_float() = 0; 321 #ifdef _LP64 322 virtual void pass_double() = 0; 323 #else 324 virtual void pass_double() { pass_long(); } // may be same as long 325 #endif 326 327 NativeSignatureIterator(const methodHandle& method) : SignatureIterator(method->signature()) { 328 _method = method; 329 _offset = 0; 330 _jni_offset = 0; 331 332 const int JNIEnv_words = 1; 333 const int mirror_words = 1; 334 _prepended = !is_static() ? JNIEnv_words : JNIEnv_words + mirror_words; 335 } 336 337 // iterate() calles the 2 virtual methods according to the following invocation syntax: 338 // 339 // {pass_int | pass_long | pass_object} 340 // 341 // Arguments are handled from left to right (receiver first, if any). 342 // The offset() values refer to the Java stack offsets but are 0 based and increasing. 343 // The java_offset() values count down to 0, and refer to the Java TOS. 344 // The jni_offset() values increase from 1 or 2, and refer to C arguments. 345 346 void iterate() { iterate(Fingerprinter(method()).fingerprint()); 347 } 348 349 350 // Optimized path if we have the bitvector form of signature 351 void iterate( uint64_t fingerprint ) { 352 353 if (!is_static()) { 354 // handle receiver (not handled by iterate because not in signature) 355 pass_object(); _jni_offset++; _offset++; 356 } 357 358 SignatureIterator::iterate_parameters( fingerprint ); 359 } 360 }; 361 362 363 // Handy stream for iterating over signature 364 365 class SignatureStream : public StackObj { 366 private: 367 Symbol* _signature; 368 int _begin; 369 int _end; 370 BasicType _type; 371 bool _at_return_type; 372 Symbol* _previous_name; // cache the previously looked up symbol to avoid lookups 373 GrowableArray<Symbol*>* _names; // symbols created while parsing that need to be dereferenced 374 public: 375 bool at_return_type() const { return _at_return_type; } 376 bool is_done() const; 377 void next_non_primitive(int t); 378 void next() { 379 Symbol* sig = _signature; 380 int len = sig->utf8_length(); 381 if (_end >= len) { 382 _end = len + 1; 383 return; 384 } 385 386 _begin = _end; 387 int t = sig->char_at(_begin); 388 switch (t) { 389 case 'B': _type = T_BYTE; break; 390 case 'C': _type = T_CHAR; break; 391 case 'D': _type = T_DOUBLE; break; 392 case 'F': _type = T_FLOAT; break; 393 case 'I': _type = T_INT; break; 394 case 'J': _type = T_LONG; break; 395 case 'S': _type = T_SHORT; break; 396 case 'Z': _type = T_BOOLEAN; break; 397 case 'V': _type = T_VOID; break; 398 default : next_non_primitive(t); 399 return; 400 } 401 _end++; 402 } 403 404 SignatureStream(Symbol* signature, bool is_method = true); 405 ~SignatureStream(); 406 407 bool is_object() const; // True if this argument is an object 408 bool is_array() const; // True if this argument is an array 409 BasicType type() const { return _type; } 410 Symbol* as_symbol(); 411 enum FailureMode { ReturnNull, NCDFError }; 412 ValueKlass* as_value_klass(InstanceKlass* holder); 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 SigEntryFilter; 426 typedef GrowableArrayFilterIterator<SigEntry, SigEntryFilter> ExtendedSignature; 427 428 // Used for adapter generation. One SigEntry is used per element of 429 // the signature of the method. Value type arguments are treated 430 // specially. See comment for ValueKlass::collect_fields(). 431 class SigEntry { 432 public: 433 BasicType _bt; 434 int _offset; 435 436 enum { ReservedOffset = -2 }; // Special offset to mark the reserved entry 437 438 SigEntry() 439 : _bt(T_ILLEGAL), _offset(-1) { 440 } 441 SigEntry(BasicType bt, int offset) 442 : _bt(bt), _offset(offset) {} 443 444 SigEntry(BasicType bt) 445 : _bt(bt), _offset(-1) {} 446 447 static int compare(SigEntry* e1, SigEntry* e2) { 448 if (e1->_offset != e2->_offset) { 449 return e1->_offset - e2->_offset; 450 } 451 assert((e1->_bt == T_LONG && (e2->_bt == T_LONG || e2->_bt == T_VOID)) || 452 (e1->_bt == T_DOUBLE && (e2->_bt == T_DOUBLE || e2->_bt == T_VOID)) || 453 e1->_bt == T_VALUETYPE || e2->_bt == T_VALUETYPE || e1->_bt == T_VOID || e2->_bt == T_VOID, "bad bt"); 454 if (e1->_bt == e2->_bt) { 455 assert(e1->_bt == T_VALUETYPE || e1->_bt == T_VOID, "only ones with duplicate offsets"); 456 return 0; 457 } 458 if (e1->_bt == T_VOID || 459 e2->_bt == T_VALUETYPE) { 460 return 1; 461 } 462 if (e1->_bt == T_VALUETYPE || 463 e2->_bt == T_VOID) { 464 return -1; 465 } 466 ShouldNotReachHere(); 467 return 0; 468 } 469 static void add_entry(GrowableArray<SigEntry>* sig, BasicType bt, int offset = -1); 470 static void insert_reserved_entry(GrowableArray<SigEntry>* sig, int i, BasicType bt); 471 static bool is_reserved_entry(const GrowableArray<SigEntry>* sig, int i); 472 static bool skip_value_delimiters(const GrowableArray<SigEntry>* sig, int i); 473 static int fill_sig_bt(const GrowableArray<SigEntry>* sig, BasicType* sig_bt); 474 static TempNewSymbol create_symbol(const GrowableArray<SigEntry>* sig); 475 476 static bool next_is_reserved(ExtendedSignature& sig, BasicType& bt, bool can_be_void = false); 477 }; 478 479 class SigEntryFilter { 480 public: 481 bool operator()(const SigEntry& entry) { return entry._bt != T_VALUETYPE && entry._bt != T_VOID; } 482 }; 483 484 #ifdef ASSERT 485 class SignatureVerifier : public StackObj { 486 public: 487 static bool is_valid_method_signature(const Symbol* sig); 488 static bool is_valid_type_signature(const Symbol* sig); 489 private: 490 static ssize_t is_valid_type(const char*, ssize_t); 491 }; 492 #endif 493 #endif // SHARE_RUNTIME_SIGNATURE_HPP