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