1 /*
   2  * Copyright 1997-2008 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  20  * CA 95054 USA or visit www.sun.com if you need additional information or
  21  * have any questions.
  22  *
  23  */
  24 
  25 # include "incls/_precompiled.incl"
  26 # include "incls/_vmSymbols.cpp.incl"
  27 
  28 
  29 symbolOop vmSymbols::_symbols[vmSymbols::SID_LIMIT];
  30 
  31 symbolOop vmSymbols::_type_signatures[T_VOID+1] = { NULL /*, NULL...*/ };
  32 
  33 inline int compare_symbol(symbolOop a, symbolOop b) {
  34   if (a == b)  return 0;
  35   // follow the natural address order:
  36   return (address)a > (address)b ? +1 : -1;
  37 }
  38 
  39 static vmSymbols::SID vm_symbol_index[vmSymbols::SID_LIMIT];
  40 extern "C" {
  41   static int compare_vmsymbol_sid(const void* void_a, const void* void_b) {
  42     symbolOop a = vmSymbols::symbol_at(*((vmSymbols::SID*) void_a));
  43     symbolOop b = vmSymbols::symbol_at(*((vmSymbols::SID*) void_b));
  44     return compare_symbol(a, b);
  45   }
  46 }
  47 
  48 #ifndef PRODUCT
  49 #define VM_SYMBOL_ENUM_NAME_BODY(name, string) #name "\0"
  50 static const char* vm_symbol_enum_names =
  51   VM_SYMBOLS_DO(VM_SYMBOL_ENUM_NAME_BODY, VM_ALIAS_IGNORE)
  52   "\0";
  53 static const char* vm_symbol_enum_name(vmSymbols::SID sid) {
  54   const char* string = &vm_symbol_enum_names[0];
  55   int skip = (int)sid - (int)vmSymbols::FIRST_SID;
  56   for (; skip != 0; skip--) {
  57     size_t skiplen = strlen(string);
  58     if (skiplen == 0)  return "<unknown>";  // overflow
  59     string += skiplen+1;
  60   }
  61   return string;
  62 }
  63 #endif //PRODUCT
  64 
  65 // Put all the VM symbol strings in one place.
  66 // Makes for a more compact libjvm.
  67 #define VM_SYMBOL_BODY(name, string) string "\0"
  68 static const char* vm_symbol_bodies = VM_SYMBOLS_DO(VM_SYMBOL_BODY, VM_ALIAS_IGNORE);
  69 
  70 void vmSymbols::initialize(TRAPS) {
  71   assert((int)SID_LIMIT <= (1<<log2_SID_LIMIT), "must fit in this bitfield");
  72   assert((int)SID_LIMIT*5 > (1<<log2_SID_LIMIT), "make the bitfield smaller, please");
  73 
  74   if (!UseSharedSpaces) {
  75     const char* string = &vm_symbol_bodies[0];
  76     for (int index = (int)FIRST_SID; index < (int)SID_LIMIT; index++) {
  77       symbolOop sym = oopFactory::new_symbol(string, CHECK);
  78       _symbols[index] = sym;
  79       string += strlen(string); // skip string body
  80       string += 1;              // skip trailing null
  81     }
  82 
  83     _type_signatures[T_BYTE]    = byte_signature();
  84     _type_signatures[T_CHAR]    = char_signature();
  85     _type_signatures[T_DOUBLE]  = double_signature();
  86     _type_signatures[T_FLOAT]   = float_signature();
  87     _type_signatures[T_INT]     = int_signature();
  88     _type_signatures[T_LONG]    = long_signature();
  89     _type_signatures[T_SHORT]   = short_signature();
  90     _type_signatures[T_BOOLEAN] = bool_signature();
  91     _type_signatures[T_VOID]    = void_signature();
  92     // no single signatures for T_OBJECT or T_ARRAY
  93   }
  94 
  95 #ifdef ASSERT
  96   // Check for duplicates:
  97   for (int i1 = (int)FIRST_SID; i1 < (int)SID_LIMIT; i1++) {
  98     symbolOop sym = symbol_at((SID)i1);
  99     for (int i2 = (int)FIRST_SID; i2 < i1; i2++) {
 100       if (symbol_at((SID)i2) == sym) {
 101         tty->print("*** Duplicate VM symbol SIDs %s(%d) and %s(%d): \"",
 102                    vm_symbol_enum_name((SID)i2), i2,
 103                    vm_symbol_enum_name((SID)i1), i1);
 104         sym->print_symbol_on(tty);
 105         tty->print_cr("\"");
 106       }
 107     }
 108   }
 109 #endif //ASSERT
 110 
 111   // Create an index for find_id:
 112   {
 113     for (int index = (int)FIRST_SID; index < (int)SID_LIMIT; index++) {
 114       vm_symbol_index[index] = (SID)index;
 115     }
 116     int num_sids = SID_LIMIT-FIRST_SID;
 117     qsort(&vm_symbol_index[FIRST_SID], num_sids, sizeof(vm_symbol_index[0]),
 118           compare_vmsymbol_sid);
 119   }
 120 
 121 #ifdef ASSERT
 122   {
 123     // Spot-check correspondence between strings, symbols, and enums:
 124     assert(_symbols[NO_SID] == NULL, "must be");
 125     const char* str = "java/lang/Object";
 126     symbolOop sym = oopFactory::new_symbol(str, CHECK);
 127     assert(strcmp(str, (char*)sym->base()) == 0, "");
 128     assert(sym == java_lang_Object(), "");
 129     SID sid = VM_SYMBOL_ENUM_NAME(java_lang_Object);
 130     assert(find_sid(sym) == sid, "");
 131     assert(symbol_at(sid) == sym, "");
 132 
 133     // Make sure find_sid produces the right answer in each case.
 134     for (int index = (int)FIRST_SID; index < (int)SID_LIMIT; index++) {
 135       sym = symbol_at((SID)index);
 136       sid = find_sid(sym);
 137       assert(sid == (SID)index, "symbol index works");
 138       // Note:  If there are duplicates, this assert will fail.
 139       // A "Duplicate VM symbol" message will have already been printed.
 140     }
 141 
 142     // The string "format" happens (at the moment) not to be a vmSymbol,
 143     // though it is a method name in java.lang.String.
 144     str = "format";
 145     sym = oopFactory::new_symbol(str, CHECK);
 146     sid = find_sid(sym);
 147     assert(sid == NO_SID, "symbol index works (negative test)");
 148   }
 149 #endif
 150 }
 151 
 152 
 153 #ifndef PRODUCT
 154 const char* vmSymbols::name_for(vmSymbols::SID sid) {
 155   if (sid == NO_SID)
 156     return "NO_SID";
 157   const char* string = &vm_symbol_bodies[0];
 158   for (int index = (int)FIRST_SID; index < (int)SID_LIMIT; index++) {
 159     if (index == (int)sid)
 160       return string;
 161     string += strlen(string); // skip string body
 162     string += 1;              // skip trailing null
 163   }
 164   return "BAD_SID";
 165 }
 166 #endif
 167 
 168 
 169 
 170 void vmSymbols::oops_do(OopClosure* f, bool do_all) {
 171   for (int index = (int)FIRST_SID; index < (int)SID_LIMIT; index++) {
 172     f->do_oop((oop*) &_symbols[index]);
 173   }
 174   for (int i = 0; i < T_VOID+1; i++) {
 175     if (_type_signatures[i] != NULL) {
 176       assert(i >= T_BOOLEAN, "checking");
 177       f->do_oop((oop*)&_type_signatures[i]);
 178     } else if (do_all) {
 179       f->do_oop((oop*)&_type_signatures[i]);
 180     }
 181   }
 182 }
 183 
 184 
 185 BasicType vmSymbols::signature_type(symbolOop s) {
 186   assert(s != NULL, "checking");
 187   for (int i = T_BOOLEAN; i < T_VOID+1; i++) {
 188     if (s == _type_signatures[i]) {
 189       return (BasicType)i;
 190     }
 191   }
 192   return T_OBJECT;
 193 }
 194 
 195 
 196 static int mid_hint = (int)vmSymbols::FIRST_SID+1;
 197 
 198 #ifndef PRODUCT
 199 static int find_sid_calls, find_sid_probes;
 200 // (Typical counts are calls=7000 and probes=17000.)
 201 #endif
 202 
 203 vmSymbols::SID vmSymbols::find_sid(symbolOop symbol) {
 204   // Handle the majority of misses by a bounds check.
 205   // Then, use a binary search over the index.
 206   // Expected trip count is less than log2_SID_LIMIT, about eight.
 207   // This is slow but acceptable, given that calls are not
 208   // dynamically common.  (methodOop::intrinsic_id has a cache.)
 209   NOT_PRODUCT(find_sid_calls++);
 210   int min = (int)FIRST_SID, max = (int)SID_LIMIT - 1;
 211   SID sid = NO_SID, sid1;
 212   int cmp1;
 213   sid1 = vm_symbol_index[min];
 214   cmp1 = compare_symbol(symbol, symbol_at(sid1));
 215   if (cmp1 <= 0) {              // before the first
 216     if (cmp1 == 0)  sid = sid1;
 217   } else {
 218     sid1 = vm_symbol_index[max];
 219     cmp1 = compare_symbol(symbol, symbol_at(sid1));
 220     if (cmp1 >= 0) {            // after the last
 221       if (cmp1 == 0)  sid = sid1;
 222     } else {
 223       // After checking the extremes, do a binary search.
 224       ++min; --max;             // endpoints are done
 225       int mid = mid_hint;       // start at previous success
 226       while (max >= min) {
 227         assert(mid >= min && mid <= max, "");
 228         NOT_PRODUCT(find_sid_probes++);
 229         sid1 = vm_symbol_index[mid];
 230         cmp1 = compare_symbol(symbol, symbol_at(sid1));
 231         if (cmp1 == 0) {
 232           mid_hint = mid;
 233           sid = sid1;
 234           break;
 235         }
 236         if (cmp1 < 0)
 237           max = mid - 1;        // symbol < symbol_at(sid)
 238         else
 239           min = mid + 1;
 240 
 241         // Pick a new probe point:
 242         mid = (max + min) / 2;
 243       }
 244     }
 245   }
 246 
 247 #ifdef ASSERT
 248   // Perform the exhaustive self-check the first 1000 calls,
 249   // and every 100 calls thereafter.
 250   static int find_sid_check_count = -2000;
 251   if ((uint)++find_sid_check_count > (uint)100) {
 252     if (find_sid_check_count > 0)  find_sid_check_count = 0;
 253 
 254     // Make sure this is the right answer, using linear search.
 255     // (We have already proven that there are no duplicates in the list.)
 256     SID sid2 = NO_SID;
 257     for (int index = (int)FIRST_SID; index < (int)SID_LIMIT; index++) {
 258       symbolOop sym2 = symbol_at((SID)index);
 259       if (sym2 == symbol) {
 260         sid2 = (SID)index;
 261         break;
 262       }
 263     }
 264     // Unless it's a duplicate, assert that the sids are the same.
 265     if (_symbols[sid] != _symbols[sid2]) {
 266       assert(sid == sid2, "binary same as linear search");
 267     }
 268   }
 269 #endif //ASSERT
 270 
 271   return sid;
 272 }
 273 
 274 
 275 #define VM_INTRINSIC_INITIALIZE(id, klass, name, sig, flags) #id "\0"
 276 static const char* vm_intrinsic_name_bodies =
 277   VM_INTRINSICS_DO(VM_INTRINSIC_INITIALIZE,
 278                    VM_SYMBOL_IGNORE, VM_SYMBOL_IGNORE, VM_SYMBOL_IGNORE, VM_ALIAS_IGNORE);
 279 
 280 static const char* vm_intrinsic_name_table[vmIntrinsics::ID_LIMIT];
 281 
 282 const char* vmIntrinsics::name_at(vmIntrinsics::ID id) {
 283   const char** nt = &vm_intrinsic_name_table[0];
 284   if (nt[_none] == NULL) {
 285     char* string = (char*) &vm_intrinsic_name_bodies[0];
 286     for (int index = FIRST_ID; index < ID_LIMIT; index++) {
 287       nt[index] = string;
 288       string += strlen(string); // skip string body
 289       string += 1;              // skip trailing null
 290     }
 291     assert(!strcmp(nt[_hashCode], "_hashCode"), "lined up");
 292     nt[_none] = "_none";
 293   }
 294   if ((uint)id < (uint)ID_LIMIT)
 295     return vm_intrinsic_name_table[(uint)id];
 296   else
 297     return "(unknown intrinsic)";
 298 }
 299 
 300 // These are flag-matching functions:
 301 inline bool match_F_R(jshort flags) {
 302   const int req = 0;
 303   const int neg = JVM_ACC_STATIC | JVM_ACC_SYNCHRONIZED;
 304   return (flags & (req | neg)) == req;
 305 }
 306 inline bool match_F_RN(jshort flags) {
 307   const int req = JVM_ACC_NATIVE;
 308   const int neg = JVM_ACC_STATIC | JVM_ACC_SYNCHRONIZED;
 309   return (flags & (req | neg)) == req;
 310 }
 311 inline bool match_F_S(jshort flags) {
 312   const int req = JVM_ACC_STATIC;
 313   const int neg = JVM_ACC_SYNCHRONIZED;
 314   return (flags & (req | neg)) == req;
 315 }
 316 inline bool match_F_SN(jshort flags) {
 317   const int req = JVM_ACC_STATIC | JVM_ACC_NATIVE;
 318   const int neg = JVM_ACC_SYNCHRONIZED;
 319   return (flags & (req | neg)) == req;
 320 }
 321 inline bool match_F_RNY(jshort flags) {
 322   const int req = JVM_ACC_NATIVE | JVM_ACC_SYNCHRONIZED;
 323   const int neg = JVM_ACC_STATIC;
 324   return (flags & (req | neg)) == req;
 325 }
 326 
 327 // These are for forming case labels:
 328 #define ID3(x, y, z) (( jint)(z) +                                  \
 329                       ((jint)(y) <<    vmSymbols::log2_SID_LIMIT) + \
 330                       ((jint)(x) << (2*vmSymbols::log2_SID_LIMIT))  )
 331 #define SID_ENUM(n) vmSymbols::VM_SYMBOL_ENUM_NAME(n)
 332 
 333 vmIntrinsics::ID vmIntrinsics::find_id(vmSymbols::SID holder,
 334                                        vmSymbols::SID name,
 335                                        vmSymbols::SID sig,
 336                                        jshort flags) {
 337   assert((int)vmSymbols::SID_LIMIT <= (1<<vmSymbols::log2_SID_LIMIT), "must fit");
 338 
 339   // Let the C compiler build the decision tree.
 340 
 341 #define VM_INTRINSIC_CASE(id, klass, name, sig, fcode) \
 342   case ID3(SID_ENUM(klass), SID_ENUM(name), SID_ENUM(sig)): \
 343     if (!match_##fcode(flags))  break; \
 344     return id;
 345 
 346   switch (ID3(holder, name, sig)) {
 347     VM_INTRINSICS_DO(VM_INTRINSIC_CASE,
 348                      VM_SYMBOL_IGNORE, VM_SYMBOL_IGNORE, VM_SYMBOL_IGNORE, VM_ALIAS_IGNORE);
 349   }
 350   return vmIntrinsics::_none;
 351 
 352 #undef VM_INTRINSIC_CASE
 353 }
 354 
 355 
 356 const char* vmIntrinsics::short_name_as_C_string(vmIntrinsics::ID id, char* buf, int buflen) {
 357   const char* str = name_at(id);
 358 #ifndef PRODUCT
 359   const char* kname = vmSymbols::name_for(class_for(id));
 360   const char* mname = vmSymbols::name_for(name_for(id));
 361   const char* sname = vmSymbols::name_for(signature_for(id));
 362   const char* fname = "";
 363   switch (flags_for(id)) {
 364   case F_RN: fname = "native ";        break;
 365   case F_SN: fname = "native static "; break;
 366   case F_S:  fname = "static ";        break;
 367   case F_RNY:fname = "native synchronized "; break;
 368   }
 369   const char* kptr = strrchr(kname, '/');
 370   if (kptr != NULL)  kname = kptr + 1;
 371   int len = jio_snprintf(buf, buflen, "%s: %s%s.%s%s",
 372                          str, fname, kname, mname, sname);
 373   if (len < buflen)
 374     str = buf;
 375 #endif //PRODUCT
 376   return str;
 377 }
 378 
 379 
 380 // These are for friendly printouts of intrinsics:
 381 
 382 vmSymbols::SID vmIntrinsics::class_for(vmIntrinsics::ID id) {
 383 #ifndef PRODUCT
 384 #define VM_INTRINSIC_CASE(id, klass, name, sig, fcode) \
 385   case id: return SID_ENUM(klass);
 386 
 387   switch (id) {
 388     VM_INTRINSICS_DO(VM_INTRINSIC_CASE,
 389                      VM_SYMBOL_IGNORE, VM_SYMBOL_IGNORE, VM_SYMBOL_IGNORE, VM_ALIAS_IGNORE);
 390   }
 391 #undef VM_INTRINSIC_CASE
 392 #endif //PRODUCT
 393   return vmSymbols::NO_SID;
 394 }
 395 
 396 vmSymbols::SID vmIntrinsics::name_for(vmIntrinsics::ID id) {
 397 #ifndef PRODUCT
 398 #define VM_INTRINSIC_CASE(id, klass, name, sig, fcode) \
 399   case id: return SID_ENUM(name);
 400 
 401   switch (id) {
 402     VM_INTRINSICS_DO(VM_INTRINSIC_CASE,
 403                      VM_SYMBOL_IGNORE, VM_SYMBOL_IGNORE, VM_SYMBOL_IGNORE, VM_ALIAS_IGNORE);
 404   }
 405 #undef VM_INTRINSIC_CASE
 406 #endif //PRODUCT
 407   return vmSymbols::NO_SID;
 408 }
 409 
 410 vmSymbols::SID vmIntrinsics::signature_for(vmIntrinsics::ID id) {
 411 #ifndef PRODUCT
 412 #define VM_INTRINSIC_CASE(id, klass, name, sig, fcode) \
 413   case id: return SID_ENUM(sig);
 414 
 415   switch (id) {
 416     VM_INTRINSICS_DO(VM_INTRINSIC_CASE,
 417                      VM_SYMBOL_IGNORE, VM_SYMBOL_IGNORE, VM_SYMBOL_IGNORE, VM_ALIAS_IGNORE);
 418   }
 419 #undef VM_INTRINSIC_CASE
 420 #endif //PRODUCT
 421   return vmSymbols::NO_SID;
 422 }
 423 
 424 vmIntrinsics::Flags vmIntrinsics::flags_for(vmIntrinsics::ID id) {
 425 #ifndef PRODUCT
 426 #define VM_INTRINSIC_CASE(id, klass, name, sig, fcode) \
 427   case id: return fcode;
 428 
 429   switch (id) {
 430     VM_INTRINSICS_DO(VM_INTRINSIC_CASE,
 431                      VM_SYMBOL_IGNORE, VM_SYMBOL_IGNORE, VM_SYMBOL_IGNORE, VM_ALIAS_IGNORE);
 432   }
 433 #undef VM_INTRINSIC_CASE
 434 #endif //PRODUCT
 435   return F_none;
 436 }
 437 
 438 
 439 #ifndef PRODUCT
 440 // verify_method performs an extra check on a matched intrinsic method
 441 
 442 static bool match_method(methodOop m, symbolOop n, symbolOop s) {
 443   return (m->name() == n &&
 444           m->signature() == s);
 445 }
 446 
 447 static vmIntrinsics::ID match_method_with_klass(methodOop m, symbolOop mk) {
 448 #define VM_INTRINSIC_MATCH(id, klassname, namepart, sigpart, flags) \
 449   { symbolOop k = vmSymbols::klassname(); \
 450     if (mk == k) { \
 451       symbolOop n = vmSymbols::namepart(); \
 452       symbolOop s = vmSymbols::sigpart(); \
 453       if (match_method(m, n, s)) \
 454         return vmIntrinsics::id; \
 455     } }
 456   VM_INTRINSICS_DO(VM_INTRINSIC_MATCH,
 457                    VM_SYMBOL_IGNORE, VM_SYMBOL_IGNORE, VM_SYMBOL_IGNORE, VM_ALIAS_IGNORE);
 458   return vmIntrinsics::_none;
 459 #undef VM_INTRINSIC_MATCH
 460 }
 461 
 462 void vmIntrinsics::verify_method(ID actual_id, methodOop m) {
 463   symbolOop mk = Klass::cast(m->method_holder())->name();
 464   ID declared_id = match_method_with_klass(m, mk);
 465 
 466   if (declared_id == actual_id)  return; // success
 467 
 468   if (declared_id == _none && actual_id != _none && mk == vmSymbols::java_lang_StrictMath()) {
 469     // Here are a few special cases in StrictMath not declared in vmSymbols.hpp.
 470     switch (actual_id) {
 471     case _min:
 472     case _max:
 473     case _dsqrt:
 474       declared_id = match_method_with_klass(m, vmSymbols::java_lang_Math());
 475       if (declared_id == actual_id)  return; // acceptable alias
 476       break;
 477     }
 478   }
 479 
 480   const char* declared_name = name_at(declared_id);
 481   const char* actual_name   = name_at(actual_id);
 482   methodHandle mh = m;
 483   m = NULL;
 484   ttyLocker ttyl;
 485   if (xtty != NULL) {
 486     xtty->begin_elem("intrinsic_misdeclared actual='%s' declared='%s'",
 487                      actual_name, declared_name);
 488     xtty->method(mh);
 489     xtty->end_elem("");
 490   }
 491   if (PrintMiscellaneous && (WizardMode || Verbose)) {
 492     tty->print_cr("*** misidentified method; %s(%d) should be %s(%d):",
 493                   declared_name, declared_id, actual_name, actual_id);
 494     mh()->print_short_name(tty);
 495     tty->cr();
 496   }
 497 }
 498 #endif //PRODUCT