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 "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 int parse_type(); // returns the parameter size in words (0 for void) 56 void check_signature_end(); 57 58 public: 59 // Definitions used in generating and iterating the 60 // bit field form of the signature generated by the 61 // Fingerprinter. 62 enum { 63 static_feature_size = 1, 64 is_static_bit = 1, 65 66 result_feature_size = 4, 67 result_feature_mask = 0xF, 68 parameter_feature_size = 4, 69 parameter_feature_mask = 0xF, 70 71 bool_parm = 1, 72 byte_parm = 2, 73 char_parm = 3, 74 short_parm = 4, 75 int_parm = 5, 76 long_parm = 6, 77 float_parm = 7, 78 double_parm = 8, 79 obj_parm = 9, 80 done_parm = 10, // marker for end of parameters 81 82 // max parameters is wordsize minus 83 // The sign bit, termination field, the result and static bit fields 84 max_size_of_parameters = (BitsPerLong-1 - 85 result_feature_size - parameter_feature_size - 86 static_feature_size) / parameter_feature_size 87 }; 88 89 // Constructors 90 SignatureIterator(Symbol* signature); 91 92 // Iteration 93 void dispatch_field(); // dispatches once for field signatures 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_array (int begin, int end) = 0; 117 118 static bool is_static(uint64_t fingerprint) { 119 assert(fingerprint != (uint64_t)CONST64(-1), "invalid fingerprint"); 120 return fingerprint & is_static_bit; 121 } 122 static BasicType return_type(uint64_t fingerprint) { 123 assert(fingerprint != (uint64_t)CONST64(-1), "invalid fingerprint"); 124 return (BasicType) ((fingerprint >> static_feature_size) & result_feature_mask); 125 } 126 }; 127 128 129 // Specialized SignatureIterators: Used to compute signature specific values. 130 131 class SignatureTypeNames : public SignatureIterator { 132 protected: 133 virtual void type_name(const char* name) = 0; 134 135 void do_bool() { type_name("jboolean"); } 136 void do_char() { type_name("jchar" ); } 137 void do_float() { type_name("jfloat" ); } 138 void do_double() { type_name("jdouble" ); } 139 void do_byte() { type_name("jbyte" ); } 140 void do_short() { type_name("jshort" ); } 141 void do_int() { type_name("jint" ); } 142 void do_long() { type_name("jlong" ); } 143 void do_void() { type_name("void" ); } 144 void do_object(int begin, int end) { type_name("jobject" ); } 145 void do_array (int begin, int end) { type_name("jobject" ); } 146 147 public: 148 SignatureTypeNames(Symbol* signature) : SignatureIterator(signature) {} 149 }; 150 151 152 class SignatureInfo: public SignatureIterator { 153 protected: 154 bool _has_iterated; // need this because iterate cannot be called in constructor (set is virtual!) 155 bool _has_iterated_return; 156 int _size; 157 158 void lazy_iterate_parameters() { if (!_has_iterated) { iterate_parameters(); _has_iterated = true; } } 159 void lazy_iterate_return() { if (!_has_iterated_return) { iterate_returntype(); _has_iterated_return = true; } } 160 161 virtual void set(int size, BasicType type) = 0; 162 163 void do_bool () { set(T_BOOLEAN_size, T_BOOLEAN); } 164 void do_char () { set(T_CHAR_size , T_CHAR ); } 165 void do_float () { set(T_FLOAT_size , T_FLOAT ); } 166 void do_double() { set(T_DOUBLE_size , T_DOUBLE ); } 167 void do_byte () { set(T_BYTE_size , T_BYTE ); } 168 void do_short () { set(T_SHORT_size , T_SHORT ); } 169 void do_int () { set(T_INT_size , T_INT ); } 170 void do_long () { set(T_LONG_size , T_LONG ); } 171 void do_void () { set(T_VOID_size , T_VOID ); } 172 void do_object(int begin, int end) { set(T_OBJECT_size , T_OBJECT ); } 173 void do_array (int begin, int end) { set(T_ARRAY_size , T_ARRAY ); } 174 175 public: 176 SignatureInfo(Symbol* signature) : SignatureIterator(signature) { 177 _has_iterated = _has_iterated_return = false; 178 _size = 0; 179 _return_type = T_ILLEGAL; 180 } 181 182 }; 183 184 185 // Specialized SignatureIterator: Used to compute the argument size. 186 187 class ArgumentSizeComputer: public SignatureInfo { 188 private: 189 void set(int size, BasicType type) { _size += size; } 190 public: 191 ArgumentSizeComputer(Symbol* signature) : SignatureInfo(signature) {} 192 193 int size() { lazy_iterate_parameters(); return _size; } 194 }; 195 196 197 class ArgumentCount: public SignatureInfo { 198 private: 199 void set(int size, BasicType type) { _size ++; } 200 public: 201 ArgumentCount(Symbol* signature) : SignatureInfo(signature) {} 202 203 int size() { lazy_iterate_parameters(); return _size; } 204 }; 205 206 207 // Specialized SignatureIterator: Used to compute the result type. 208 209 class ResultTypeFinder: public SignatureInfo { 210 private: 211 void set(int size, BasicType type) { _return_type = type; } 212 public: 213 BasicType type() { lazy_iterate_return(); return _return_type; } 214 215 ResultTypeFinder(Symbol* signature) : SignatureInfo(signature) {} 216 }; 217 218 219 // Fingerprinter computes a unique ID for a given method. The ID 220 // is a bitvector characterizing the methods signature (incl. the receiver). 221 class Fingerprinter: public SignatureIterator { 222 private: 223 uint64_t _fingerprint; 224 int _shift_count; 225 methodHandle mh; 226 227 public: 228 229 void do_bool() { _fingerprint |= (((uint64_t)bool_parm) << _shift_count); _shift_count += parameter_feature_size; } 230 void do_char() { _fingerprint |= (((uint64_t)char_parm) << _shift_count); _shift_count += parameter_feature_size; } 231 void do_byte() { _fingerprint |= (((uint64_t)byte_parm) << _shift_count); _shift_count += parameter_feature_size; } 232 void do_short() { _fingerprint |= (((uint64_t)short_parm) << _shift_count); _shift_count += parameter_feature_size; } 233 void do_int() { _fingerprint |= (((uint64_t)int_parm) << _shift_count); _shift_count += parameter_feature_size; } 234 void do_long() { _fingerprint |= (((uint64_t)long_parm) << _shift_count); _shift_count += parameter_feature_size; } 235 void do_float() { _fingerprint |= (((uint64_t)float_parm) << _shift_count); _shift_count += parameter_feature_size; } 236 void do_double() { _fingerprint |= (((uint64_t)double_parm) << _shift_count); _shift_count += parameter_feature_size; } 237 238 void do_object(int begin, int end) { _fingerprint |= (((uint64_t)obj_parm) << _shift_count); _shift_count += parameter_feature_size; } 239 void do_array (int begin, int end) { _fingerprint |= (((uint64_t)obj_parm) << _shift_count); _shift_count += parameter_feature_size; } 240 241 void do_void() { ShouldNotReachHere(); } 242 243 Fingerprinter(const methodHandle& method) : SignatureIterator(method->signature()) { 244 mh = method; 245 _fingerprint = 0; 246 } 247 248 uint64_t fingerprint() { 249 // See if we fingerprinted this method already 250 if (mh->constMethod()->fingerprint() != CONST64(0)) { 251 return mh->constMethod()->fingerprint(); 252 } 253 254 if (mh->size_of_parameters() > max_size_of_parameters ) { 255 _fingerprint = (uint64_t)CONST64(-1); 256 mh->constMethod()->set_fingerprint(_fingerprint); 257 return _fingerprint; 258 } 259 260 assert( (int)mh->result_type() <= (int)result_feature_mask, "bad result type"); 261 _fingerprint = mh->result_type(); 262 _fingerprint <<= static_feature_size; 263 if (mh->is_static()) _fingerprint |= 1; 264 _shift_count = result_feature_size + static_feature_size; 265 iterate_parameters(); 266 _fingerprint |= ((uint64_t)done_parm) << _shift_count;// mark end of sig 267 mh->constMethod()->set_fingerprint(_fingerprint); 268 return _fingerprint; 269 } 270 }; 271 272 273 // Specialized SignatureIterator: Used for native call purposes 274 275 class NativeSignatureIterator: public SignatureIterator { 276 private: 277 methodHandle _method; 278 // We need separate JNI and Java offset values because in 64 bit mode, 279 // the argument offsets are not in sync with the Java stack. 280 // For example a long takes up 1 "C" stack entry but 2 Java stack entries. 281 int _offset; // The java stack offset 282 int _prepended; // number of prepended JNI parameters (1 JNIEnv, plus 1 mirror if static) 283 int _jni_offset; // the current parameter offset, starting with 0 284 285 void do_bool () { pass_int(); _jni_offset++; _offset++; } 286 void do_char () { pass_int(); _jni_offset++; _offset++; } 287 void do_float () { pass_float(); _jni_offset++; _offset++; } 288 #ifdef _LP64 289 void do_double() { pass_double(); _jni_offset++; _offset += 2; } 290 #else 291 void do_double() { pass_double(); _jni_offset += 2; _offset += 2; } 292 #endif 293 void do_byte () { pass_int(); _jni_offset++; _offset++; } 294 void do_short () { pass_int(); _jni_offset++; _offset++; } 295 void do_int () { pass_int(); _jni_offset++; _offset++; } 296 #ifdef _LP64 297 void do_long () { pass_long(); _jni_offset++; _offset += 2; } 298 #else 299 void do_long () { pass_long(); _jni_offset += 2; _offset += 2; } 300 #endif 301 void do_void () { ShouldNotReachHere(); } 302 void do_object(int begin, int end) { pass_object(); _jni_offset++; _offset++; } 303 void do_array (int begin, int end) { pass_object(); _jni_offset++; _offset++; } 304 305 public: 306 methodHandle method() const { return _method; } 307 int offset() const { return _offset; } 308 int jni_offset() const { return _jni_offset + _prepended; } 309 // int java_offset() const { return method()->size_of_parameters() - _offset - 1; } 310 bool is_static() const { return method()->is_static(); } 311 virtual void pass_int() = 0; 312 virtual void pass_long() = 0; 313 virtual void pass_object() = 0; 314 virtual void pass_float() = 0; 315 #ifdef _LP64 316 virtual void pass_double() = 0; 317 #else 318 virtual void pass_double() { pass_long(); } // may be same as long 319 #endif 320 321 NativeSignatureIterator(const methodHandle& method) : SignatureIterator(method->signature()) { 322 _method = method; 323 _offset = 0; 324 _jni_offset = 0; 325 326 const int JNIEnv_words = 1; 327 const int mirror_words = 1; 328 _prepended = !is_static() ? JNIEnv_words : JNIEnv_words + mirror_words; 329 } 330 331 // iterate() calles the 2 virtual methods according to the following invocation syntax: 332 // 333 // {pass_int | pass_long | pass_object} 334 // 335 // Arguments are handled from left to right (receiver first, if any). 336 // The offset() values refer to the Java stack offsets but are 0 based and increasing. 337 // The java_offset() values count down to 0, and refer to the Java TOS. 338 // The jni_offset() values increase from 1 or 2, and refer to C arguments. 339 340 void iterate() { iterate(Fingerprinter(method()).fingerprint()); 341 } 342 343 344 // Optimized path if we have the bitvector form of signature 345 void iterate( uint64_t fingerprint ) { 346 347 if (!is_static()) { 348 // handle receiver (not handled by iterate because not in signature) 349 pass_object(); _jni_offset++; _offset++; 350 } 351 352 SignatureIterator::iterate_parameters( fingerprint ); 353 } 354 }; 355 356 357 // Handy stream for iterating over signature 358 359 class SignatureStream : public StackObj { 360 private: 361 Symbol* _signature; 362 int _begin; 363 int _end; 364 BasicType _type; 365 bool _at_return_type; 366 GrowableArray<Symbol*>* _names; // symbols created while parsing signature 367 368 public: 369 bool at_return_type() const { return _at_return_type; } 370 bool is_done() const; 371 void next_non_primitive(int t); 372 void next() { 373 Symbol* sig = _signature; 374 int len = sig->utf8_length(); 375 if (_end >= len) { 376 _end = len + 1; 377 return; 378 } 379 380 _begin = _end; 381 int t = sig->char_at(_begin); 382 switch (t) { 383 case 'B': _type = T_BYTE; break; 384 case 'C': _type = T_CHAR; break; 385 case 'D': _type = T_DOUBLE; break; 386 case 'F': _type = T_FLOAT; break; 387 case 'I': _type = T_INT; break; 388 case 'J': _type = T_LONG; break; 389 case 'S': _type = T_SHORT; break; 390 case 'Z': _type = T_BOOLEAN; break; 391 case 'V': _type = T_VOID; break; 392 default : next_non_primitive(t); 393 return; 394 } 395 _end++; 396 } 397 398 SignatureStream(Symbol* signature, bool is_method = true); 399 ~SignatureStream(); 400 401 bool is_object() const; // True if this argument is an object 402 bool is_array() const; // True if this argument is an array 403 BasicType type() const { return _type; } 404 Symbol* as_symbol(TRAPS); 405 enum FailureMode { ReturnNull, CNFException, NCDFError }; 406 Klass* as_klass(Handle class_loader, Handle protection_domain, FailureMode failure_mode, TRAPS); 407 oop as_java_mirror(Handle class_loader, Handle protection_domain, FailureMode failure_mode, TRAPS); 408 const u1* raw_bytes() { return _signature->bytes() + _begin; } 409 int raw_length() { return _end - _begin; } 410 411 // return same as_symbol except allocation of new symbols is avoided. 412 Symbol* as_symbol_or_null(); 413 414 // count the number of references in the signature 415 int reference_parameter_count(); 416 }; 417 418 class SignatureVerifier : public StackObj { 419 public: 420 // Returns true if the symbol is valid method or type signature 421 static bool is_valid_signature(Symbol* sig); 422 423 static bool is_valid_method_signature(Symbol* sig); 424 static bool is_valid_type_signature(Symbol* sig); 425 private: 426 427 static ssize_t is_valid_type(const char*, ssize_t); 428 static bool invalid_name_char(char); 429 }; 430 431 #endif // SHARE_RUNTIME_SIGNATURE_HPP