1 /* 2 * Copyright (c) 1997, 2012, 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 #include "utilities/top.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 void skip_optional_size(); 57 int parse_type(); // returns the parameter size in words (0 for void) 58 void check_signature_end(); 59 60 public: 61 // Definitions used in generating and iterating the 62 // bit field form of the signature generated by the 63 // Fingerprinter. 64 enum { 65 static_feature_size = 1, 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 }; 118 119 120 // Specialized SignatureIterators: Used to compute signature specific values. 121 122 class SignatureTypeNames : public SignatureIterator { 123 protected: 124 virtual void type_name(const char* name) = 0; 125 126 void do_bool() { type_name("jboolean"); } 127 void do_char() { type_name("jchar" ); } 128 void do_float() { type_name("jfloat" ); } 129 void do_double() { type_name("jdouble" ); } 130 void do_byte() { type_name("jbyte" ); } 131 void do_short() { type_name("jshort" ); } 132 void do_int() { type_name("jint" ); } 133 void do_long() { type_name("jlong" ); } 134 void do_void() { type_name("void" ); } 135 void do_object(int begin, int end) { type_name("jobject" ); } 136 void do_array (int begin, int end) { type_name("jobject" ); } 137 138 public: 139 SignatureTypeNames(Symbol* signature) : SignatureIterator(signature) {} 140 }; 141 142 143 class SignatureInfo: public SignatureIterator { 144 protected: 145 bool _has_iterated; // need this because iterate cannot be called in constructor (set is virtual!) 146 bool _has_iterated_return; 147 int _size; 148 149 void lazy_iterate_parameters() { if (!_has_iterated) { iterate_parameters(); _has_iterated = true; } } 150 void lazy_iterate_return() { if (!_has_iterated_return) { iterate_returntype(); _has_iterated_return = true; } } 151 152 virtual void set(int size, BasicType type) = 0; 153 154 void do_bool () { set(T_BOOLEAN_size, T_BOOLEAN); } 155 void do_char () { set(T_CHAR_size , T_CHAR ); } 156 void do_float () { set(T_FLOAT_size , T_FLOAT ); } 157 void do_double() { set(T_DOUBLE_size , T_DOUBLE ); } 158 void do_byte () { set(T_BYTE_size , T_BYTE ); } 159 void do_short () { set(T_SHORT_size , T_SHORT ); } 160 void do_int () { set(T_INT_size , T_INT ); } 161 void do_long () { set(T_LONG_size , T_LONG ); } 162 void do_void () { set(T_VOID_size , T_VOID ); } 163 void do_object(int begin, int end) { set(T_OBJECT_size , T_OBJECT ); } 164 void do_array (int begin, int end) { set(T_ARRAY_size , T_ARRAY ); } 165 166 public: 167 SignatureInfo(Symbol* signature) : SignatureIterator(signature) { 168 _has_iterated = _has_iterated_return = false; 169 _size = 0; 170 _return_type = T_ILLEGAL; 171 } 172 173 }; 174 175 176 // Specialized SignatureIterator: Used to compute the argument size. 177 178 class ArgumentSizeComputer: public SignatureInfo { 179 private: 180 void set(int size, BasicType type) { _size += size; } 181 public: 182 ArgumentSizeComputer(Symbol* signature) : SignatureInfo(signature) {} 183 184 int size() { lazy_iterate_parameters(); return _size; } 185 }; 186 187 188 class ArgumentCount: public SignatureInfo { 189 private: 190 void set(int size, BasicType type) { _size ++; } 191 public: 192 ArgumentCount(Symbol* signature) : SignatureInfo(signature) {} 193 194 int size() { lazy_iterate_parameters(); return _size; } 195 }; 196 197 198 // Specialized SignatureIterator: Used to compute the result type. 199 200 class ResultTypeFinder: public SignatureInfo { 201 private: 202 void set(int size, BasicType type) { _return_type = type; } 203 public: 204 BasicType type() { lazy_iterate_return(); return _return_type; } 205 206 ResultTypeFinder(Symbol* signature) : SignatureInfo(signature) {} 207 }; 208 209 210 // Fingerprinter computes a unique ID for a given method. The ID 211 // is a bitvector characterizing the methods signature (incl. the receiver). 212 class Fingerprinter: public SignatureIterator { 213 private: 214 uint64_t _fingerprint; 215 int _shift_count; 216 methodHandle mh; 217 218 public: 219 220 void do_bool() { _fingerprint |= (((uint64_t)bool_parm) << _shift_count); _shift_count += parameter_feature_size; } 221 void do_char() { _fingerprint |= (((uint64_t)char_parm) << _shift_count); _shift_count += parameter_feature_size; } 222 void do_byte() { _fingerprint |= (((uint64_t)byte_parm) << _shift_count); _shift_count += parameter_feature_size; } 223 void do_short() { _fingerprint |= (((uint64_t)short_parm) << _shift_count); _shift_count += parameter_feature_size; } 224 void do_int() { _fingerprint |= (((uint64_t)int_parm) << _shift_count); _shift_count += parameter_feature_size; } 225 void do_long() { _fingerprint |= (((uint64_t)long_parm) << _shift_count); _shift_count += parameter_feature_size; } 226 void do_float() { _fingerprint |= (((uint64_t)float_parm) << _shift_count); _shift_count += parameter_feature_size; } 227 void do_double() { _fingerprint |= (((uint64_t)double_parm) << _shift_count); _shift_count += parameter_feature_size; } 228 229 void do_object(int begin, int end) { _fingerprint |= (((uint64_t)obj_parm) << _shift_count); _shift_count += parameter_feature_size; } 230 void do_array (int begin, int end) { _fingerprint |= (((uint64_t)obj_parm) << _shift_count); _shift_count += parameter_feature_size; } 231 232 void do_void() { ShouldNotReachHere(); } 233 234 Fingerprinter(methodHandle method) : SignatureIterator(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 Symbol* _signature; 353 int _begin; 354 int _end; 355 BasicType _type; 356 bool _at_return_type; 357 GrowableArray<Symbol*>* _names; // symbols created while parsing signature 358 359 public: 360 bool at_return_type() const { return _at_return_type; } 361 bool is_done() const; 362 void next_non_primitive(int t); 363 void next() { 364 Symbol* sig = _signature; 365 int len = sig->utf8_length(); 366 if (_end >= len) { 367 _end = len + 1; 368 return; 369 } 370 371 _begin = _end; 372 int t = sig->byte_at(_begin); 373 switch (t) { 374 case 'B': _type = T_BYTE; break; 375 case 'C': _type = T_CHAR; break; 376 case 'D': _type = T_DOUBLE; break; 377 case 'F': _type = T_FLOAT; break; 378 case 'I': _type = T_INT; break; 379 case 'J': _type = T_LONG; break; 380 case 'S': _type = T_SHORT; break; 381 case 'Z': _type = T_BOOLEAN; break; 382 case 'V': _type = T_VOID; break; 383 default : next_non_primitive(t); 384 return; 385 } 386 _end++; 387 } 388 389 SignatureStream(Symbol* signature, bool is_method = true); 390 ~SignatureStream(); 391 392 bool is_object() const; // True if this argument is an object 393 bool is_array() const; // True if this argument is an array 394 BasicType type() const { return _type; } 395 Symbol* as_symbol(TRAPS); 396 enum FailureMode { ReturnNull, CNFException, NCDFError }; 397 Klass* as_klass(Handle class_loader, Handle protection_domain, FailureMode failure_mode, TRAPS); 398 oop as_java_mirror(Handle class_loader, Handle protection_domain, FailureMode failure_mode, TRAPS); 399 const jbyte* raw_bytes() { return _signature->bytes() + _begin; } 400 int raw_length() { return _end - _begin; } 401 402 // return same as_symbol except allocation of new symbols is avoided. 403 Symbol* as_symbol_or_null(); 404 405 // count the number of references in the signature 406 int reference_parameter_count(); 407 }; 408 409 class SignatureVerifier : public StackObj { 410 public: 411 // Returns true if the symbol is valid method or type signature 412 static bool is_valid_signature(Symbol* sig); 413 414 static bool is_valid_method_signature(Symbol* sig); 415 static bool is_valid_type_signature(Symbol* sig); 416 private: 417 418 static ssize_t is_valid_type(const char*, ssize_t); 419 static bool invalid_name_char(char); 420 }; 421 422 #endif // SHARE_VM_RUNTIME_SIGNATURE_HPP