1 /* 2 * Copyright (c) 1997, 2015, 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_VM_RUNTIME_SIGNATURE_HPP 26 #define SHARE_VM_RUNTIME_SIGNATURE_HPP 27 28 #include "memory/allocation.hpp" 29 #include "oops/method.hpp" 30 31 // SignatureIterators iterate over a Java signature (or parts of it). 32 // (Syntax according to: "The Java Virtual Machine Specification" by 33 // Tim Lindholm & Frank Yellin; section 4.3 Descriptors; p. 89ff.) 34 // 35 // Example: Iterating over ([Lfoo;D)I using 36 // 0123456789 37 // 38 // iterate_parameters() calls: do_array(2, 7); do_double(); 39 // iterate_returntype() calls: do_int(); 40 // iterate() calls: do_array(2, 7); do_double(); do_int(); 41 // 42 // is_return_type() is: false ; false ; true 43 // 44 // NOTE: The new optimizer has an alternate, for-loop based signature 45 // iterator implemented in opto/type.cpp, TypeTuple::make(). 46 47 class SignatureIterator: public ResourceObj { 48 protected: 49 Symbol* _signature; // the signature to iterate over 50 int _index; // the current character index (only valid during iteration) 51 int _parameter_index; // the current parameter index (0 outside iteration phase) 52 BasicType _return_type; 53 54 void expect(char c); 55 void skip_optional_size(); 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 valuetype_parm = 10, 82 done_parm = 11, // marker for end of parameters 83 84 // max parameters is wordsize minus 85 // The sign bit, termination field, the result and static bit fields 86 max_size_of_parameters = (BitsPerLong-1 - 87 result_feature_size - parameter_feature_size - 88 static_feature_size) / parameter_feature_size 89 }; 90 91 // Constructors 92 SignatureIterator(Symbol* signature); 93 94 // Iteration 95 void dispatch_field(); // dispatches once for field signatures 96 void iterate_parameters(); // iterates over parameters only 97 void iterate_parameters( uint64_t fingerprint ); 98 void iterate_returntype(); // iterates over returntype only 99 void iterate(); // iterates over whole signature 100 // Returns the word index of the current parameter; 101 int parameter_index() const { return _parameter_index; } 102 bool is_return_type() const { return parameter_index() < 0; } 103 BasicType get_ret_type() const { return _return_type; } 104 105 // Basic types 106 virtual void do_bool () = 0; 107 virtual void do_char () = 0; 108 virtual void do_float () = 0; 109 virtual void do_double() = 0; 110 virtual void do_byte () = 0; 111 virtual void do_short () = 0; 112 virtual void do_int () = 0; 113 virtual void do_long () = 0; 114 virtual void do_void () = 0; 115 116 // Object types (begin indexes the first character of the entry, end indexes the first character after the entry) 117 virtual void do_object(int begin, int end) = 0; 118 virtual void do_array (int begin, int end) = 0; 119 virtual void do_valuetype(int begin, int end) = 0; 120 121 static bool is_static(uint64_t fingerprint) { 122 assert(fingerprint != (uint64_t)CONST64(-1), "invalid fingerprint"); 123 return fingerprint & is_static_bit; 124 } 125 static BasicType return_type(uint64_t fingerprint) { 126 assert(fingerprint != (uint64_t)CONST64(-1), "invalid fingerprint"); 127 return (BasicType) ((fingerprint >> static_feature_size) & result_feature_mask); 128 } 129 }; 130 131 132 // Specialized SignatureIterators: Used to compute signature specific values. 133 134 class SignatureTypeNames : public SignatureIterator { 135 protected: 136 virtual void type_name(const char* name) = 0; 137 138 void do_bool() { type_name("jboolean"); } 139 void do_char() { type_name("jchar" ); } 140 void do_float() { type_name("jfloat" ); } 141 void do_double() { type_name("jdouble" ); } 142 void do_byte() { type_name("jbyte" ); } 143 void do_short() { type_name("jshort" ); } 144 void do_int() { type_name("jint" ); } 145 void do_long() { type_name("jlong" ); } 146 void do_void() { type_name("void" ); } 147 void do_object(int begin, int end) { type_name("jobject" ); } 148 void do_array (int begin, int end) { type_name("jobject" ); } 149 void do_valuetype(int begin, int end){ type_name("jvaluetype"); } 150 151 public: 152 SignatureTypeNames(Symbol* signature) : SignatureIterator(signature) {} 153 }; 154 155 156 class SignatureInfo: public SignatureIterator { 157 protected: 158 bool _has_iterated; // need this because iterate cannot be called in constructor (set is virtual!) 159 bool _has_iterated_return; 160 int _size; 161 162 void lazy_iterate_parameters() { if (!_has_iterated) { iterate_parameters(); _has_iterated = true; } } 163 void lazy_iterate_return() { if (!_has_iterated_return) { iterate_returntype(); _has_iterated_return = true; } } 164 165 virtual void set(int size, BasicType type) = 0; 166 167 void do_bool () { set(T_BOOLEAN_size, T_BOOLEAN); } 168 void do_char () { set(T_CHAR_size , T_CHAR ); } 169 void do_float () { set(T_FLOAT_size , T_FLOAT ); } 170 void do_double() { set(T_DOUBLE_size , T_DOUBLE ); } 171 void do_byte () { set(T_BYTE_size , T_BYTE ); } 172 void do_short () { set(T_SHORT_size , T_SHORT ); } 173 void do_int () { set(T_INT_size , T_INT ); } 174 void do_long () { set(T_LONG_size , T_LONG ); } 175 void do_void () { set(T_VOID_size , T_VOID ); } 176 void do_object(int begin, int end) { set(T_OBJECT_size , T_OBJECT ); } 177 void do_array (int begin, int end) { set(T_ARRAY_size , T_ARRAY ); } 178 void do_valuetype(int begin, int end){ set(T_VALUETYPE_size, T_VALUETYPE); } 179 180 public: 181 SignatureInfo(Symbol* signature) : SignatureIterator(signature) { 182 _has_iterated = _has_iterated_return = false; 183 _size = 0; 184 _return_type = T_ILLEGAL; 185 } 186 187 }; 188 189 190 // Specialized SignatureIterator: Used to compute the argument size. 191 192 class ArgumentSizeComputer: public SignatureInfo { 193 private: 194 void set(int size, BasicType type) { _size += size; } 195 public: 196 ArgumentSizeComputer(Symbol* signature) : SignatureInfo(signature) {} 197 198 int size() { lazy_iterate_parameters(); return _size; } 199 }; 200 201 202 class ArgumentCount: public SignatureInfo { 203 private: 204 void set(int size, BasicType type) { _size ++; } 205 public: 206 ArgumentCount(Symbol* signature) : SignatureInfo(signature) {} 207 208 int size() { lazy_iterate_parameters(); return _size; } 209 }; 210 211 212 // Specialized SignatureIterator: Used to compute the result type. 213 214 class ResultTypeFinder: public SignatureInfo { 215 private: 216 void set(int size, BasicType type) { _return_type = type; } 217 public: 218 BasicType type() { lazy_iterate_return(); return _return_type; } 219 220 ResultTypeFinder(Symbol* signature) : SignatureInfo(signature) {} 221 }; 222 223 224 // Fingerprinter computes a unique ID for a given method. The ID 225 // is a bitvector characterizing the methods signature (incl. the receiver). 226 class Fingerprinter: public SignatureIterator { 227 private: 228 uint64_t _fingerprint; 229 int _shift_count; 230 methodHandle mh; 231 232 public: 233 234 void do_bool() { _fingerprint |= (((uint64_t)bool_parm) << _shift_count); _shift_count += parameter_feature_size; } 235 void do_char() { _fingerprint |= (((uint64_t)char_parm) << _shift_count); _shift_count += parameter_feature_size; } 236 void do_byte() { _fingerprint |= (((uint64_t)byte_parm) << _shift_count); _shift_count += parameter_feature_size; } 237 void do_short() { _fingerprint |= (((uint64_t)short_parm) << _shift_count); _shift_count += parameter_feature_size; } 238 void do_int() { _fingerprint |= (((uint64_t)int_parm) << _shift_count); _shift_count += parameter_feature_size; } 239 void do_long() { _fingerprint |= (((uint64_t)long_parm) << _shift_count); _shift_count += parameter_feature_size; } 240 void do_float() { _fingerprint |= (((uint64_t)float_parm) << _shift_count); _shift_count += parameter_feature_size; } 241 void do_double() { _fingerprint |= (((uint64_t)double_parm) << _shift_count); _shift_count += parameter_feature_size; } 242 243 void do_object(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 void do_valuetype(int begin, int end) { _fingerprint |= (((uint64_t)valuetype_parm) << _shift_count); _shift_count += parameter_feature_size; } 246 247 void do_void() { ShouldNotReachHere(); } 248 249 Fingerprinter(const methodHandle& method) : SignatureIterator(method->signature()) { 250 mh = method; 251 _fingerprint = 0; 252 } 253 254 uint64_t fingerprint() { 255 // See if we fingerprinted this method already 256 if (mh->constMethod()->fingerprint() != CONST64(0)) { 257 return mh->constMethod()->fingerprint(); 258 } 259 260 if (mh->size_of_parameters() > max_size_of_parameters ) { 261 _fingerprint = (uint64_t)CONST64(-1); 262 mh->constMethod()->set_fingerprint(_fingerprint); 263 return _fingerprint; 264 } 265 266 assert( (int)mh->result_type() <= (int)result_feature_mask, "bad result type"); 267 _fingerprint = mh->result_type(); 268 _fingerprint <<= static_feature_size; 269 if (mh->is_static()) _fingerprint |= 1; 270 _shift_count = result_feature_size + static_feature_size; 271 iterate_parameters(); 272 _fingerprint |= ((uint64_t)done_parm) << _shift_count;// mark end of sig 273 mh->constMethod()->set_fingerprint(_fingerprint); 274 return _fingerprint; 275 } 276 }; 277 278 279 // Specialized SignatureIterator: Used for native call purposes 280 281 class NativeSignatureIterator: public SignatureIterator { 282 private: 283 methodHandle _method; 284 // We need separate JNI and Java offset values because in 64 bit mode, 285 // the argument offsets are not in sync with the Java stack. 286 // For example a long takes up 1 "C" stack entry but 2 Java stack entries. 287 int _offset; // The java stack offset 288 int _prepended; // number of prepended JNI parameters (1 JNIEnv, plus 1 mirror if static) 289 int _jni_offset; // the current parameter offset, starting with 0 290 291 void do_bool () { pass_int(); _jni_offset++; _offset++; } 292 void do_char () { pass_int(); _jni_offset++; _offset++; } 293 void do_float () { pass_float(); _jni_offset++; _offset++; } 294 #ifdef _LP64 295 void do_double() { pass_double(); _jni_offset++; _offset += 2; } 296 #else 297 void do_double() { pass_double(); _jni_offset += 2; _offset += 2; } 298 #endif 299 void do_byte () { pass_int(); _jni_offset++; _offset++; } 300 void do_short () { pass_int(); _jni_offset++; _offset++; } 301 void do_int () { pass_int(); _jni_offset++; _offset++; } 302 #ifdef _LP64 303 void do_long () { pass_long(); _jni_offset++; _offset += 2; } 304 #else 305 void do_long () { pass_long(); _jni_offset += 2; _offset += 2; } 306 #endif 307 void do_void () { ShouldNotReachHere(); } 308 void do_object(int begin, int end) { pass_object(); _jni_offset++; _offset++; } 309 void do_array (int begin, int end) { pass_object(); _jni_offset++; _offset++; } 310 void do_valuetype(int begin, int end){ pass_valuetype(); _jni_offset++; _offset++; } 311 312 public: 313 methodHandle method() const { return _method; } 314 int offset() const { return _offset; } 315 int jni_offset() const { return _jni_offset + _prepended; } 316 // int java_offset() const { return method()->size_of_parameters() - _offset - 1; } 317 bool is_static() const { return method()->is_static(); } 318 virtual void pass_int() = 0; 319 virtual void pass_long() = 0; 320 virtual void pass_object() = 0; 321 virtual void pass_valuetype() = 0; 322 virtual void pass_float() = 0; 323 #ifdef _LP64 324 virtual void pass_double() = 0; 325 #else 326 virtual void pass_double() { pass_long(); } // may be same as long 327 #endif 328 329 NativeSignatureIterator(const methodHandle& method) : SignatureIterator(method->signature()) { 330 _method = method; 331 _offset = 0; 332 _jni_offset = 0; 333 334 const int JNIEnv_words = 1; 335 const int mirror_words = 1; 336 _prepended = !is_static() ? JNIEnv_words : JNIEnv_words + mirror_words; 337 } 338 339 // iterate() calles the 2 virtual methods according to the following invocation syntax: 340 // 341 // {pass_int | pass_long | pass_object} 342 // 343 // Arguments are handled from left to right (receiver first, if any). 344 // The offset() values refer to the Java stack offsets but are 0 based and increasing. 345 // The java_offset() values count down to 0, and refer to the Java TOS. 346 // The jni_offset() values increase from 1 or 2, and refer to C arguments. 347 348 void iterate() { iterate(Fingerprinter(method()).fingerprint()); 349 } 350 351 352 // Optimized path if we have the bitvector form of signature 353 void iterate( uint64_t fingerprint ) { 354 355 if (!is_static()) { 356 // handle receiver (not handled by iterate because not in signature) 357 pass_object(); _jni_offset++; _offset++; 358 } 359 360 SignatureIterator::iterate_parameters( fingerprint ); 361 } 362 }; 363 364 365 // Handy stream for iterating over signature 366 367 class SignatureStream : public StackObj { 368 private: 369 Symbol* _signature; 370 int _begin; 371 int _end; 372 BasicType _type; 373 bool _at_return_type; 374 GrowableArray<Symbol*>* _names; // symbols created while parsing signature 375 376 public: 377 bool at_return_type() const { return _at_return_type; } 378 bool is_done() const; 379 void next_non_primitive(int t); 380 void next() { 381 Symbol* sig = _signature; 382 int len = sig->utf8_length(); 383 if (_end >= len) { 384 _end = len + 1; 385 return; 386 } 387 388 _begin = _end; 389 int t = sig->byte_at(_begin); 390 switch (t) { 391 case 'B': _type = T_BYTE; break; 392 case 'C': _type = T_CHAR; break; 393 case 'D': _type = T_DOUBLE; break; 394 case 'F': _type = T_FLOAT; break; 395 case 'I': _type = T_INT; break; 396 case 'J': _type = T_LONG; break; 397 case 'S': _type = T_SHORT; break; 398 case 'Z': _type = T_BOOLEAN; break; 399 case 'V': _type = T_VOID; break; 400 default : next_non_primitive(t); 401 return; 402 } 403 _end++; 404 } 405 406 SignatureStream(Symbol* signature, bool is_method = true); 407 ~SignatureStream(); 408 409 bool is_object() const; // True if this argument is an object 410 bool is_array() const; // True if this argument is an array 411 BasicType type() const { return _type; } 412 Symbol* as_symbol(TRAPS); 413 enum FailureMode { ReturnNull, CNFException, NCDFError }; 414 Klass* as_klass(Handle class_loader, Handle protection_domain, FailureMode failure_mode, TRAPS); 415 oop as_java_mirror(Handle class_loader, Handle protection_domain, FailureMode failure_mode, TRAPS); 416 const jbyte* raw_bytes() { return _signature->bytes() + _begin; } 417 int raw_length() { return _end - _begin; } 418 419 // return same as_symbol except allocation of new symbols is avoided. 420 Symbol* as_symbol_or_null(); 421 422 // count the number of references in the signature 423 int reference_parameter_count(); 424 }; 425 426 class SignatureVerifier : public StackObj { 427 public: 428 // Returns true if the symbol is valid method or type signature 429 static bool is_valid_signature(Symbol* sig); 430 431 static bool is_valid_method_signature(Symbol* sig); 432 static bool is_valid_type_signature(Symbol* sig); 433 private: 434 435 static ssize_t is_valid_type(const char*, ssize_t); 436 static bool invalid_name_char(char); 437 }; 438 439 // Used for adapter generation. One SigEntry is used per element of 440 // the signature of the method. Value type arguments are treated 441 // specially. See comment for ValueKlass::collect_fields(). 442 class SigEntry VALUE_OBJ_CLASS_SPEC { 443 public: 444 BasicType _bt; 445 int _offset; 446 447 SigEntry() 448 : _bt(T_ILLEGAL), _offset(-1) { 449 } 450 SigEntry(BasicType bt, int offset) 451 : _bt(bt), _offset(offset) {} 452 453 SigEntry(BasicType bt) 454 : _bt(bt), _offset(-1) {} 455 456 static int compare(SigEntry* e1, SigEntry* e2) { 457 if (e1->_offset != e2->_offset) { 458 return e1->_offset - e2->_offset; 459 } 460 assert((e1->_bt == T_LONG && (e2->_bt == T_LONG || e2->_bt == T_VOID)) || 461 (e1->_bt == T_DOUBLE && (e2->_bt == T_DOUBLE || e2->_bt == T_VOID)) || 462 e1->_bt == T_VALUETYPE || e2->_bt == T_VALUETYPE || e1->_bt == T_VOID || e2->_bt == T_VOID, "bad bt"); 463 if (e1->_bt == e2->_bt) { 464 assert(e1->_bt == T_VALUETYPE || e1->_bt == T_VOID, "only ones with duplicate offsets"); 465 return 0; 466 } 467 if (e1->_bt == T_VOID || 468 e2->_bt == T_VALUETYPE) { 469 return 1; 470 } 471 if (e1->_bt == T_VALUETYPE || 472 e2->_bt == T_VOID) { 473 return -1; 474 } 475 ShouldNotReachHere(); 476 return 0; 477 } 478 static int count_fields(const GrowableArray<SigEntry>& sig_extended); 479 static void fill_sig_bt(const GrowableArray<SigEntry>& sig_extended, BasicType* sig_bt_cc, int total_args_passed_cc, bool skip_vt); 480 }; 481 482 #endif // SHARE_VM_RUNTIME_SIGNATURE_HPP