1 /*
   2  * Copyright (c) 1997, 2011, 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 #include "precompiled.hpp"
  26 #include "interpreter/interpreter.hpp"
  27 #include "interpreter/interpreterGenerator.hpp"
  28 #include "interpreter/interpreterRuntime.hpp"
  29 #include "interpreter/templateTable.hpp"
  30 
  31 #ifndef CC_INTERP
  32 
  33 # define __ _masm->
  34 
  35 void TemplateInterpreter::initialize() {
  36   if (_code != NULL) return;
  37   // assertions
  38   assert((int)Bytecodes::number_of_codes <= (int)DispatchTable::length,
  39          "dispatch table too small");
  40 
  41   AbstractInterpreter::initialize();
  42 
  43   TemplateTable::initialize();
  44 
  45   // generate interpreter
  46   { ResourceMark rm;
  47     TraceTime timer("Interpreter generation", TraceStartupTime);
  48     int code_size = InterpreterCodeSize;
  49     NOT_PRODUCT(code_size *= 4;)  // debug uses extra interpreter code space
  50     _code = new StubQueue(new InterpreterCodeletInterface, code_size, NULL,
  51                           "Interpreter");
  52     InterpreterGenerator g(_code);
  53     if (PrintInterpreter) print();
  54   }
  55 
  56   // initialize dispatch table
  57   _active_table = _normal_table;
  58 }
  59 
  60 //------------------------------------------------------------------------------------------------------------------------
  61 // Implementation of EntryPoint
  62 
  63 EntryPoint::EntryPoint() {
  64   assert(number_of_states == 9, "check the code below");
  65   _entry[btos] = NULL;
  66   _entry[ctos] = NULL;
  67   _entry[stos] = NULL;
  68   _entry[atos] = NULL;
  69   _entry[itos] = NULL;
  70   _entry[ltos] = NULL;
  71   _entry[ftos] = NULL;
  72   _entry[dtos] = NULL;
  73   _entry[vtos] = NULL;
  74 }
  75 
  76 
  77 EntryPoint::EntryPoint(address bentry, address centry, address sentry, address aentry, address ientry, address lentry, address fentry, address dentry, address ventry) {
  78   assert(number_of_states == 9, "check the code below");
  79   _entry[btos] = bentry;
  80   _entry[ctos] = centry;
  81   _entry[stos] = sentry;
  82   _entry[atos] = aentry;
  83   _entry[itos] = ientry;
  84   _entry[ltos] = lentry;
  85   _entry[ftos] = fentry;
  86   _entry[dtos] = dentry;
  87   _entry[vtos] = ventry;
  88 }
  89 
  90 
  91 void EntryPoint::set_entry(TosState state, address entry) {
  92   assert(0 <= state && state < number_of_states, "state out of bounds");
  93   _entry[state] = entry;
  94 }
  95 
  96 
  97 address EntryPoint::entry(TosState state) const {
  98   assert(0 <= state && state < number_of_states, "state out of bounds");
  99   return _entry[state];
 100 }
 101 
 102 
 103 void EntryPoint::print() {
 104   tty->print("[");
 105   for (int i = 0; i < number_of_states; i++) {
 106     if (i > 0) tty->print(", ");
 107     tty->print(INTPTR_FORMAT, _entry[i]);
 108   }
 109   tty->print("]");
 110 }
 111 
 112 
 113 bool EntryPoint::operator == (const EntryPoint& y) {
 114   int i = number_of_states;
 115   while (i-- > 0) {
 116     if (_entry[i] != y._entry[i]) return false;
 117   }
 118   return true;
 119 }
 120 
 121 
 122 //------------------------------------------------------------------------------------------------------------------------
 123 // Implementation of DispatchTable
 124 
 125 EntryPoint DispatchTable::entry(int i) const {
 126   assert(0 <= i && i < length, "index out of bounds");
 127   return
 128     EntryPoint(
 129       _table[btos][i],
 130       _table[ctos][i],
 131       _table[stos][i],
 132       _table[atos][i],
 133       _table[itos][i],
 134       _table[ltos][i],
 135       _table[ftos][i],
 136       _table[dtos][i],
 137       _table[vtos][i]
 138     );
 139 }
 140 
 141 
 142 void DispatchTable::set_entry(int i, EntryPoint& entry) {
 143   assert(0 <= i && i < length, "index out of bounds");
 144   assert(number_of_states == 9, "check the code below");
 145   _table[btos][i] = entry.entry(btos);
 146   _table[ctos][i] = entry.entry(ctos);
 147   _table[stos][i] = entry.entry(stos);
 148   _table[atos][i] = entry.entry(atos);
 149   _table[itos][i] = entry.entry(itos);
 150   _table[ltos][i] = entry.entry(ltos);
 151   _table[ftos][i] = entry.entry(ftos);
 152   _table[dtos][i] = entry.entry(dtos);
 153   _table[vtos][i] = entry.entry(vtos);
 154 }
 155 
 156 
 157 bool DispatchTable::operator == (DispatchTable& y) {
 158   int i = length;
 159   while (i-- > 0) {
 160     EntryPoint t = y.entry(i); // for compiler compatibility (BugId 4150096)
 161     if (!(entry(i) == t)) return false;
 162   }
 163   return true;
 164 }
 165 
 166 address    TemplateInterpreter::_remove_activation_entry                    = NULL;
 167 address    TemplateInterpreter::_remove_activation_preserving_args_entry    = NULL;
 168 
 169 
 170 address    TemplateInterpreter::_throw_ArrayIndexOutOfBoundsException_entry = NULL;
 171 address    TemplateInterpreter::_throw_ArrayStoreException_entry            = NULL;
 172 address    TemplateInterpreter::_throw_ArithmeticException_entry            = NULL;
 173 address    TemplateInterpreter::_throw_ClassCastException_entry             = NULL;
 174 address    TemplateInterpreter::_throw_WrongMethodType_entry                = NULL;
 175 address    TemplateInterpreter::_throw_NullPointerException_entry           = NULL;
 176 address    TemplateInterpreter::_throw_StackOverflowError_entry             = NULL;
 177 address    TemplateInterpreter::_throw_exception_entry                      = NULL;
 178 
 179 #ifndef PRODUCT
 180 EntryPoint TemplateInterpreter::_trace_code;
 181 #endif // !PRODUCT
 182 EntryPoint TemplateInterpreter::_return_entry[TemplateInterpreter::number_of_return_entries];
 183 EntryPoint TemplateInterpreter::_earlyret_entry;
 184 EntryPoint TemplateInterpreter::_deopt_entry [TemplateInterpreter::number_of_deopt_entries ];
 185 EntryPoint TemplateInterpreter::_continuation_entry;
 186 EntryPoint TemplateInterpreter::_safept_entry;
 187 
 188 address    TemplateInterpreter::_return_3_addrs_by_index[TemplateInterpreter::number_of_return_addrs];
 189 address    TemplateInterpreter::_return_5_addrs_by_index[TemplateInterpreter::number_of_return_addrs];
 190 
 191 DispatchTable TemplateInterpreter::_active_table;
 192 DispatchTable TemplateInterpreter::_normal_table;
 193 DispatchTable TemplateInterpreter::_safept_table;
 194 address    TemplateInterpreter::_wentry_point[DispatchTable::length];
 195 
 196 TemplateInterpreterGenerator::TemplateInterpreterGenerator(StubQueue* _code): AbstractInterpreterGenerator(_code) {
 197   _unimplemented_bytecode    = NULL;
 198   _illegal_bytecode_sequence = NULL;
 199 }
 200 
 201 static const BasicType types[Interpreter::number_of_result_handlers] = {
 202   T_BOOLEAN,
 203   T_CHAR   ,
 204   T_BYTE   ,
 205   T_SHORT  ,
 206   T_INT    ,
 207   T_LONG   ,
 208   T_VOID   ,
 209   T_FLOAT  ,
 210   T_DOUBLE ,
 211   T_OBJECT
 212 };
 213 
 214 void TemplateInterpreterGenerator::generate_all() {
 215   AbstractInterpreterGenerator::generate_all();
 216 
 217   { CodeletMark cm(_masm, "error exits");
 218     _unimplemented_bytecode    = generate_error_exit("unimplemented bytecode");
 219     _illegal_bytecode_sequence = generate_error_exit("illegal bytecode sequence - method not verified");
 220   }
 221 
 222 #ifndef PRODUCT
 223   if (TraceBytecodes) {
 224     CodeletMark cm(_masm, "bytecode tracing support");
 225     Interpreter::_trace_code =
 226       EntryPoint(
 227         generate_trace_code(btos),
 228         generate_trace_code(ctos),
 229         generate_trace_code(stos),
 230         generate_trace_code(atos),
 231         generate_trace_code(itos),
 232         generate_trace_code(ltos),
 233         generate_trace_code(ftos),
 234         generate_trace_code(dtos),
 235         generate_trace_code(vtos)
 236       );
 237   }
 238 #endif // !PRODUCT
 239 
 240   { CodeletMark cm(_masm, "return entry points");
 241     for (int i = 0; i < Interpreter::number_of_return_entries; i++) {
 242       Interpreter::_return_entry[i] =
 243         EntryPoint(
 244           generate_return_entry_for(itos, i),
 245           generate_return_entry_for(itos, i),
 246           generate_return_entry_for(itos, i),
 247           generate_return_entry_for(atos, i),
 248           generate_return_entry_for(itos, i),
 249           generate_return_entry_for(ltos, i),
 250           generate_return_entry_for(ftos, i),
 251           generate_return_entry_for(dtos, i),
 252           generate_return_entry_for(vtos, i)
 253         );
 254     }
 255   }
 256 
 257   { CodeletMark cm(_masm, "earlyret entry points");
 258     Interpreter::_earlyret_entry =
 259       EntryPoint(
 260         generate_earlyret_entry_for(btos),
 261         generate_earlyret_entry_for(ctos),
 262         generate_earlyret_entry_for(stos),
 263         generate_earlyret_entry_for(atos),
 264         generate_earlyret_entry_for(itos),
 265         generate_earlyret_entry_for(ltos),
 266         generate_earlyret_entry_for(ftos),
 267         generate_earlyret_entry_for(dtos),
 268         generate_earlyret_entry_for(vtos)
 269       );
 270   }
 271 
 272   { CodeletMark cm(_masm, "deoptimization entry points");
 273     for (int i = 0; i < Interpreter::number_of_deopt_entries; i++) {
 274       Interpreter::_deopt_entry[i] =
 275         EntryPoint(
 276           generate_deopt_entry_for(itos, i),
 277           generate_deopt_entry_for(itos, i),
 278           generate_deopt_entry_for(itos, i),
 279           generate_deopt_entry_for(atos, i),
 280           generate_deopt_entry_for(itos, i),
 281           generate_deopt_entry_for(ltos, i),
 282           generate_deopt_entry_for(ftos, i),
 283           generate_deopt_entry_for(dtos, i),
 284           generate_deopt_entry_for(vtos, i)
 285         );
 286     }
 287   }
 288 
 289   { CodeletMark cm(_masm, "result handlers for native calls");
 290     // The various result converter stublets.
 291     int is_generated[Interpreter::number_of_result_handlers];
 292     memset(is_generated, 0, sizeof(is_generated));
 293 
 294     for (int i = 0; i < Interpreter::number_of_result_handlers; i++) {
 295       BasicType type = types[i];
 296       if (!is_generated[Interpreter::BasicType_as_index(type)]++) {
 297         Interpreter::_native_abi_to_tosca[Interpreter::BasicType_as_index(type)] = generate_result_handler_for(type);
 298       }
 299     }
 300   }
 301 
 302   for (int j = 0; j < number_of_states; j++) {
 303     const TosState states[] = {btos, ctos, stos, itos, ltos, ftos, dtos, atos, vtos};
 304     int index = Interpreter::TosState_as_index(states[j]);
 305     Interpreter::_return_3_addrs_by_index[index] = Interpreter::return_entry(states[j], 3);
 306     Interpreter::_return_5_addrs_by_index[index] = Interpreter::return_entry(states[j], 5);
 307   }
 308 
 309   { CodeletMark cm(_masm, "continuation entry points");
 310     Interpreter::_continuation_entry =
 311       EntryPoint(
 312         generate_continuation_for(btos),
 313         generate_continuation_for(ctos),
 314         generate_continuation_for(stos),
 315         generate_continuation_for(atos),
 316         generate_continuation_for(itos),
 317         generate_continuation_for(ltos),
 318         generate_continuation_for(ftos),
 319         generate_continuation_for(dtos),
 320         generate_continuation_for(vtos)
 321       );
 322   }
 323 
 324   { CodeletMark cm(_masm, "safepoint entry points");
 325     Interpreter::_safept_entry =
 326       EntryPoint(
 327         generate_safept_entry_for(btos, CAST_FROM_FN_PTR(address, InterpreterRuntime::at_safepoint)),
 328         generate_safept_entry_for(ctos, CAST_FROM_FN_PTR(address, InterpreterRuntime::at_safepoint)),
 329         generate_safept_entry_for(stos, CAST_FROM_FN_PTR(address, InterpreterRuntime::at_safepoint)),
 330         generate_safept_entry_for(atos, CAST_FROM_FN_PTR(address, InterpreterRuntime::at_safepoint)),
 331         generate_safept_entry_for(itos, CAST_FROM_FN_PTR(address, InterpreterRuntime::at_safepoint)),
 332         generate_safept_entry_for(ltos, CAST_FROM_FN_PTR(address, InterpreterRuntime::at_safepoint)),
 333         generate_safept_entry_for(ftos, CAST_FROM_FN_PTR(address, InterpreterRuntime::at_safepoint)),
 334         generate_safept_entry_for(dtos, CAST_FROM_FN_PTR(address, InterpreterRuntime::at_safepoint)),
 335         generate_safept_entry_for(vtos, CAST_FROM_FN_PTR(address, InterpreterRuntime::at_safepoint))
 336       );
 337   }
 338 
 339   { CodeletMark cm(_masm, "exception handling");
 340     // (Note: this is not safepoint safe because thread may return to compiled code)
 341     generate_throw_exception();
 342   }
 343 
 344   { CodeletMark cm(_masm, "throw exception entrypoints");
 345     Interpreter::_throw_ArrayIndexOutOfBoundsException_entry = generate_ArrayIndexOutOfBounds_handler("java/lang/ArrayIndexOutOfBoundsException");
 346     Interpreter::_throw_ArrayStoreException_entry            = generate_klass_exception_handler("java/lang/ArrayStoreException"                 );
 347     Interpreter::_throw_ArithmeticException_entry            = generate_exception_handler("java/lang/ArithmeticException"           , "/ by zero");
 348     Interpreter::_throw_ClassCastException_entry             = generate_ClassCastException_handler();
 349     Interpreter::_throw_WrongMethodType_entry                = generate_WrongMethodType_handler();
 350     Interpreter::_throw_NullPointerException_entry           = generate_exception_handler("java/lang/NullPointerException"          , NULL       );
 351     Interpreter::_throw_StackOverflowError_entry             = generate_StackOverflowError_handler();
 352   }
 353 
 354 
 355 
 356 #define method_entry(kind)                                                                    \
 357   { CodeletMark cm(_masm, "method entry point (kind = " #kind ")");                    \
 358     Interpreter::_entry_table[Interpreter::kind] = generate_method_entry(Interpreter::kind);  \
 359   }
 360 
 361   // all non-native method kinds
 362   method_entry(zerolocals)
 363   method_entry(zerolocals_synchronized)
 364   method_entry(empty)
 365   method_entry(accessor)
 366   method_entry(abstract)
 367   method_entry(method_handle)
 368   method_entry(java_lang_math_sin  )
 369   method_entry(java_lang_math_cos  )
 370   method_entry(java_lang_math_tan  )
 371   method_entry(java_lang_math_abs  )
 372   method_entry(java_lang_math_sqrt )
 373   method_entry(java_lang_math_log  )
 374   method_entry(java_lang_math_log10)
 375   method_entry(java_lang_ref_reference_get)
 376 
 377   // all native method kinds (must be one contiguous block)
 378   Interpreter::_native_entry_begin = Interpreter::code()->code_end();
 379   method_entry(native)
 380   method_entry(native_synchronized)
 381   Interpreter::_native_entry_end = Interpreter::code()->code_end();
 382 
 383 #undef method_entry
 384 
 385   // Bytecodes
 386   set_entry_points_for_all_bytes();
 387   set_safepoints_for_all_bytes();
 388 }
 389 
 390 //------------------------------------------------------------------------------------------------------------------------
 391 
 392 address TemplateInterpreterGenerator::generate_error_exit(const char* msg) {
 393   address entry = __ pc();
 394   __ stop(msg);
 395   return entry;
 396 }
 397 
 398 
 399 //------------------------------------------------------------------------------------------------------------------------
 400 
 401 void TemplateInterpreterGenerator::set_entry_points_for_all_bytes() {
 402   for (int i = 0; i < DispatchTable::length; i++) {
 403     Bytecodes::Code code = (Bytecodes::Code)i;
 404     if (Bytecodes::is_defined(code)) {
 405       set_entry_points(code);
 406     } else {
 407       set_unimplemented(i);
 408     }
 409   }
 410 }
 411 
 412 
 413 void TemplateInterpreterGenerator::set_safepoints_for_all_bytes() {
 414   for (int i = 0; i < DispatchTable::length; i++) {
 415     Bytecodes::Code code = (Bytecodes::Code)i;
 416     if (Bytecodes::is_defined(code)) Interpreter::_safept_table.set_entry(code, Interpreter::_safept_entry);
 417   }
 418 }
 419 
 420 
 421 void TemplateInterpreterGenerator::set_unimplemented(int i) {
 422   address e = _unimplemented_bytecode;
 423   EntryPoint entry(e, e, e, e, e, e, e, e, e);
 424   Interpreter::_normal_table.set_entry(i, entry);
 425   Interpreter::_wentry_point[i] = _unimplemented_bytecode;
 426 }
 427 
 428 
 429 void TemplateInterpreterGenerator::set_entry_points(Bytecodes::Code code) {
 430   CodeletMark cm(_masm, Bytecodes::name(code), code);
 431   // initialize entry points
 432   assert(_unimplemented_bytecode    != NULL, "should have been generated before");
 433   assert(_illegal_bytecode_sequence != NULL, "should have been generated before");
 434   address bep = _illegal_bytecode_sequence;
 435   address cep = _illegal_bytecode_sequence;
 436   address sep = _illegal_bytecode_sequence;
 437   address aep = _illegal_bytecode_sequence;
 438   address iep = _illegal_bytecode_sequence;
 439   address lep = _illegal_bytecode_sequence;
 440   address fep = _illegal_bytecode_sequence;
 441   address dep = _illegal_bytecode_sequence;
 442   address vep = _unimplemented_bytecode;
 443   address wep = _unimplemented_bytecode;
 444   // code for short & wide version of bytecode
 445   if (Bytecodes::is_defined(code)) {
 446     Template* t = TemplateTable::template_for(code);
 447     assert(t->is_valid(), "just checking");
 448     set_short_entry_points(t, bep, cep, sep, aep, iep, lep, fep, dep, vep);
 449   }
 450   if (Bytecodes::wide_is_defined(code)) {
 451     Template* t = TemplateTable::template_for_wide(code);
 452     assert(t->is_valid(), "just checking");
 453     set_wide_entry_point(t, wep);
 454   }
 455   // set entry points
 456   EntryPoint entry(bep, cep, sep, aep, iep, lep, fep, dep, vep);
 457   Interpreter::_normal_table.set_entry(code, entry);
 458   Interpreter::_wentry_point[code] = wep;
 459 }
 460 
 461 
 462 void TemplateInterpreterGenerator::set_wide_entry_point(Template* t, address& wep) {
 463   assert(t->is_valid(), "template must exist");
 464   assert(t->tos_in() == vtos, "only vtos tos_in supported for wide instructions");
 465   wep = __ pc(); generate_and_dispatch(t);
 466 }
 467 
 468 
 469 void TemplateInterpreterGenerator::set_short_entry_points(Template* t, address& bep, address& cep, address& sep, address& aep, address& iep, address& lep, address& fep, address& dep, address& vep) {
 470   assert(t->is_valid(), "template must exist");
 471   switch (t->tos_in()) {
 472     case btos:
 473     case ctos:
 474     case stos:
 475       ShouldNotReachHere();  // btos/ctos/stos should use itos.
 476       break;
 477     case atos: vep = __ pc(); __ pop(atos); aep = __ pc(); generate_and_dispatch(t); break;
 478     case itos: vep = __ pc(); __ pop(itos); iep = __ pc(); generate_and_dispatch(t); break;
 479     case ltos: vep = __ pc(); __ pop(ltos); lep = __ pc(); generate_and_dispatch(t); break;
 480     case ftos: vep = __ pc(); __ pop(ftos); fep = __ pc(); generate_and_dispatch(t); break;
 481     case dtos: vep = __ pc(); __ pop(dtos); dep = __ pc(); generate_and_dispatch(t); break;
 482     case vtos: set_vtos_entry_points(t, bep, cep, sep, aep, iep, lep, fep, dep, vep);     break;
 483     default  : ShouldNotReachHere();                                                 break;
 484   }
 485 }
 486 
 487 
 488 //------------------------------------------------------------------------------------------------------------------------
 489 
 490 void TemplateInterpreterGenerator::generate_and_dispatch(Template* t, TosState tos_out) {
 491   if (PrintBytecodeHistogram)                                    histogram_bytecode(t);
 492 #ifndef PRODUCT
 493   // debugging code
 494   if (CountBytecodes || TraceBytecodes || StopInterpreterAt > 0) count_bytecode();
 495   if (PrintBytecodePairHistogram)                                histogram_bytecode_pair(t);
 496   if (TraceBytecodes)                                            trace_bytecode(t);
 497   if (StopInterpreterAt > 0)                                     stop_interpreter_at();
 498   __ verify_FPU(1, t->tos_in());
 499 #endif // !PRODUCT
 500   int step;
 501   if (!t->does_dispatch()) {
 502     step = t->is_wide() ? Bytecodes::wide_length_for(t->bytecode()) : Bytecodes::length_for(t->bytecode());
 503     if (tos_out == ilgl) tos_out = t->tos_out();
 504     // compute bytecode size
 505     assert(step > 0, "just checkin'");
 506     // setup stuff for dispatching next bytecode
 507     if (ProfileInterpreter && VerifyDataPointer
 508         && methodDataOopDesc::bytecode_has_profile(t->bytecode())) {
 509       __ verify_method_data_pointer();
 510     }
 511     __ dispatch_prolog(tos_out, step);
 512   }
 513   // generate template
 514   t->generate(_masm);
 515   // advance
 516   if (t->does_dispatch()) {
 517 #ifdef ASSERT
 518     // make sure execution doesn't go beyond this point if code is broken
 519     __ should_not_reach_here();
 520 #endif // ASSERT
 521   } else {
 522     // dispatch to next bytecode
 523     __ dispatch_epilog(tos_out, step);
 524   }
 525 }
 526 
 527 //------------------------------------------------------------------------------------------------------------------------
 528 // Entry points
 529 
 530 address TemplateInterpreter::return_entry(TosState state, int length) {
 531   guarantee(0 <= length && length < Interpreter::number_of_return_entries, "illegal length");
 532   return _return_entry[length].entry(state);
 533 }
 534 
 535 
 536 address TemplateInterpreter::deopt_entry(TosState state, int length) {
 537   guarantee(0 <= length && length < Interpreter::number_of_deopt_entries, "illegal length");
 538   return _deopt_entry[length].entry(state);
 539 }
 540 
 541 //------------------------------------------------------------------------------------------------------------------------
 542 // Suport for invokes
 543 
 544 int TemplateInterpreter::TosState_as_index(TosState state) {
 545   assert( state < number_of_states , "Invalid state in TosState_as_index");
 546   assert(0 <= (int)state && (int)state < TemplateInterpreter::number_of_return_addrs, "index out of bounds");
 547   return (int)state;
 548 }
 549 
 550 
 551 //------------------------------------------------------------------------------------------------------------------------
 552 // Safepoint suppport
 553 
 554 static inline void copy_table(address* from, address* to, int size) {
 555   // Copy non-overlapping tables. The copy has to occur word wise for MT safety.
 556   while (size-- > 0) *to++ = *from++;
 557 }
 558 
 559 void TemplateInterpreter::notice_safepoints() {
 560   if (!_notice_safepoints) {
 561     // switch to safepoint dispatch table
 562     _notice_safepoints = true;
 563     copy_table((address*)&_safept_table, (address*)&_active_table, sizeof(_active_table) / sizeof(address));
 564   }
 565 }
 566 
 567 // switch from the dispatch table which notices safepoints back to the
 568 // normal dispatch table.  So that we can notice single stepping points,
 569 // keep the safepoint dispatch table if we are single stepping in JVMTI.
 570 // Note that the should_post_single_step test is exactly as fast as the
 571 // JvmtiExport::_enabled test and covers both cases.
 572 void TemplateInterpreter::ignore_safepoints() {
 573   if (_notice_safepoints) {
 574     if (!JvmtiExport::should_post_single_step()) {
 575       // switch to normal dispatch table
 576       _notice_safepoints = false;
 577       copy_table((address*)&_normal_table, (address*)&_active_table, sizeof(_active_table) / sizeof(address));
 578     }
 579   }
 580 }
 581 
 582 //------------------------------------------------------------------------------------------------------------------------
 583 // Deoptimization support
 584 
 585 // If deoptimization happens, this function returns the point of next bytecode to continue execution
 586 address TemplateInterpreter::deopt_continue_after_entry(methodOop method, address bcp, int callee_parameters, bool is_top_frame) {
 587   return AbstractInterpreter::deopt_continue_after_entry(method, bcp, callee_parameters, is_top_frame);
 588 }
 589 
 590 // If deoptimization happens, this function returns the point where the interpreter reexecutes
 591 // the bytecode.
 592 // Note: Bytecodes::_athrow (C1 only) and Bytecodes::_return are the special cases
 593 //       that do not return "Interpreter::deopt_entry(vtos, 0)"
 594 address TemplateInterpreter::deopt_reexecute_entry(methodOop method, address bcp) {
 595   assert(method->contains(bcp), "just checkin'");
 596   Bytecodes::Code code   = Bytecodes::java_code_at(method, bcp);
 597   if (code == Bytecodes::_return) {
 598     // This is used for deopt during registration of finalizers
 599     // during Object.<init>.  We simply need to resume execution at
 600     // the standard return vtos bytecode to pop the frame normally.
 601     // reexecuting the real bytecode would cause double registration
 602     // of the finalizable object.
 603     return _normal_table.entry(Bytecodes::_return).entry(vtos);
 604   } else {
 605     return AbstractInterpreter::deopt_reexecute_entry(method, bcp);
 606   }
 607 }
 608 
 609 // If deoptimization happens, the interpreter should reexecute this bytecode.
 610 // This function mainly helps the compilers to set up the reexecute bit.
 611 bool TemplateInterpreter::bytecode_should_reexecute(Bytecodes::Code code) {
 612   if (code == Bytecodes::_return) {
 613     //Yes, we consider Bytecodes::_return as a special case of reexecution
 614     return true;
 615   } else {
 616     return AbstractInterpreter::bytecode_should_reexecute(code);
 617   }
 618 }
 619 
 620 #endif // !CC_INTERP