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 #include "precompiled.hpp"
  26 #include "interpreter/interpreter.hpp"
  27 #include "interpreter/interpreterRuntime.hpp"
  28 #include "interpreter/interp_masm.hpp"
  29 #include "interpreter/templateInterpreter.hpp"
  30 #include "interpreter/templateInterpreterGenerator.hpp"
  31 #include "interpreter/templateTable.hpp"
  32 #include "logging/log.hpp"
  33 #include "memory/resourceArea.hpp"
  34 #include "runtime/safepoint.hpp"
  35 #include "runtime/timerTrace.hpp"
  36 #include "utilities/copy.hpp"
  37 
  38 #ifndef CC_INTERP
  39 
  40 # define __ _masm->
  41 
  42 void TemplateInterpreter::initialize() {
  43   if (_code != NULL) return;
  44   // assertions
  45   assert((int)Bytecodes::number_of_codes <= (int)DispatchTable::length,
  46          "dispatch table too small");
  47 
  48   AbstractInterpreter::initialize();
  49 
  50   TemplateTable::initialize();
  51 
  52   // generate interpreter
  53   { ResourceMark rm;
  54     TraceTime timer("Interpreter generation", TRACETIME_LOG(Info, startuptime));
  55     int code_size = InterpreterCodeSize;
  56     NOT_PRODUCT(code_size *= 4;)  // debug uses extra interpreter code space
  57     _code = new StubQueue(new InterpreterCodeletInterface, code_size, NULL,
  58                           "Interpreter");
  59     TemplateInterpreterGenerator g(_code);
  60     // Free the unused memory not occupied by the interpreter and the stubs
  61     _code->deallocate_unused_tail();
  62   }
  63 
  64   if (PrintInterpreter) {
  65     ResourceMark rm;
  66     print();
  67   }
  68 
  69   // initialize dispatch table
  70   _active_table = _normal_table;
  71 }
  72 
  73 //------------------------------------------------------------------------------------------------------------------------
  74 // Implementation of EntryPoint
  75 
  76 EntryPoint::EntryPoint() {
  77   assert(number_of_states == 10, "check the code below");
  78   _entry[btos] = NULL;
  79   _entry[ztos] = NULL;
  80   _entry[ctos] = NULL;
  81   _entry[stos] = NULL;
  82   _entry[atos] = NULL;
  83   _entry[itos] = NULL;
  84   _entry[ltos] = NULL;
  85   _entry[ftos] = NULL;
  86   _entry[dtos] = NULL;
  87   _entry[vtos] = NULL;
  88 }
  89 
  90 
  91 EntryPoint::EntryPoint(address bentry, address zentry, address centry, address sentry, address aentry, address ientry, address lentry, address fentry, address dentry, address ventry) {
  92   assert(number_of_states == 10, "check the code below");
  93   _entry[btos] = bentry;
  94   _entry[ztos] = zentry;
  95   _entry[ctos] = centry;
  96   _entry[stos] = sentry;
  97   _entry[atos] = aentry;
  98   _entry[itos] = ientry;
  99   _entry[ltos] = lentry;
 100   _entry[ftos] = fentry;
 101   _entry[dtos] = dentry;
 102   _entry[vtos] = ventry;
 103 }
 104 
 105 
 106 void EntryPoint::set_entry(TosState state, address entry) {
 107   assert(0 <= state && state < number_of_states, "state out of bounds");
 108   _entry[state] = entry;
 109 }
 110 
 111 
 112 address EntryPoint::entry(TosState state) const {
 113   assert(0 <= state && state < number_of_states, "state out of bounds");
 114   return _entry[state];
 115 }
 116 
 117 
 118 void EntryPoint::print() {
 119   tty->print("[");
 120   for (int i = 0; i < number_of_states; i++) {
 121     if (i > 0) tty->print(", ");
 122     tty->print(INTPTR_FORMAT, p2i(_entry[i]));
 123   }
 124   tty->print("]");
 125 }
 126 
 127 
 128 bool EntryPoint::operator == (const EntryPoint& y) {
 129   int i = number_of_states;
 130   while (i-- > 0) {
 131     if (_entry[i] != y._entry[i]) return false;
 132   }
 133   return true;
 134 }
 135 
 136 
 137 //------------------------------------------------------------------------------------------------------------------------
 138 // Implementation of DispatchTable
 139 
 140 EntryPoint DispatchTable::entry(int i) const {
 141   assert(0 <= i && i < length, "index out of bounds");
 142   return
 143     EntryPoint(
 144       _table[btos][i],
 145       _table[ztos][i],
 146       _table[ctos][i],
 147       _table[stos][i],
 148       _table[atos][i],
 149       _table[itos][i],
 150       _table[ltos][i],
 151       _table[ftos][i],
 152       _table[dtos][i],
 153       _table[vtos][i]
 154     );
 155 }
 156 
 157 
 158 void DispatchTable::set_entry(int i, EntryPoint& entry) {
 159   assert(0 <= i && i < length, "index out of bounds");
 160   assert(number_of_states == 10, "check the code below");
 161   _table[btos][i] = entry.entry(btos);
 162   _table[ztos][i] = entry.entry(ztos);
 163   _table[ctos][i] = entry.entry(ctos);
 164   _table[stos][i] = entry.entry(stos);
 165   _table[atos][i] = entry.entry(atos);
 166   _table[itos][i] = entry.entry(itos);
 167   _table[ltos][i] = entry.entry(ltos);
 168   _table[ftos][i] = entry.entry(ftos);
 169   _table[dtos][i] = entry.entry(dtos);
 170   _table[vtos][i] = entry.entry(vtos);
 171 }
 172 
 173 
 174 bool DispatchTable::operator == (DispatchTable& y) {
 175   int i = length;
 176   while (i-- > 0) {
 177     EntryPoint t = y.entry(i); // for compiler compatibility (BugId 4150096)
 178     if (!(entry(i) == t)) return false;
 179   }
 180   return true;
 181 }
 182 
 183 address    TemplateInterpreter::_remove_activation_entry                    = NULL;
 184 address    TemplateInterpreter::_remove_activation_preserving_args_entry    = NULL;
 185 
 186 
 187 address    TemplateInterpreter::_throw_ArrayIndexOutOfBoundsException_entry = NULL;
 188 address    TemplateInterpreter::_throw_ArrayStoreException_entry            = NULL;
 189 address    TemplateInterpreter::_throw_ArithmeticException_entry            = NULL;
 190 address    TemplateInterpreter::_throw_ClassCastException_entry             = NULL;
 191 address    TemplateInterpreter::_throw_NullPointerException_entry           = NULL;
 192 address    TemplateInterpreter::_throw_StackOverflowError_entry             = NULL;
 193 address    TemplateInterpreter::_throw_exception_entry                      = NULL;
 194 
 195 #ifndef PRODUCT
 196 EntryPoint TemplateInterpreter::_trace_code;
 197 #endif // !PRODUCT
 198 EntryPoint TemplateInterpreter::_return_entry[TemplateInterpreter::number_of_return_entries];
 199 EntryPoint TemplateInterpreter::_return_entryX[TemplateInterpreter::number_of_return_entries];
 200 EntryPoint TemplateInterpreter::_earlyret_entry;
 201 EntryPoint TemplateInterpreter::_deopt_entry [TemplateInterpreter::number_of_deopt_entries ];
 202 address    TemplateInterpreter::_deopt_reexecute_return_entry;
 203 EntryPoint TemplateInterpreter::_safept_entry;
 204 
 205 address TemplateInterpreter::_invoke_return_entry[TemplateInterpreter::number_of_return_addrs];
 206 address TemplateInterpreter::_invoke_return_entryX[TemplateInterpreter::number_of_return_addrs];
 207 address TemplateInterpreter::_invokeinterface_return_entry[TemplateInterpreter::number_of_return_addrs];
 208 address TemplateInterpreter::_invokedynamic_return_entry[TemplateInterpreter::number_of_return_addrs];
 209 
 210 DispatchTable TemplateInterpreter::_active_table;
 211 DispatchTable TemplateInterpreter::_normal_table;
 212 DispatchTable TemplateInterpreter::_safept_table;
 213 address    TemplateInterpreter::_wentry_point[DispatchTable::length];
 214 
 215 
 216 //------------------------------------------------------------------------------------------------------------------------
 217 // Entry points
 218 
 219 /**
 220  * Returns the return entry table for the given invoke bytecode.
 221  */
 222 address* TemplateInterpreter::invoke_return_entry_table_for(Bytecodes::Code code) {
 223   switch (code) {
 224   case Bytecodes::_invokestatic:
 225   case Bytecodes::_invokespecial:
 226   case Bytecodes::_invokevirtual:
 227   case Bytecodes::_invokehandle:
 228     return Interpreter::invoke_return_entry_table();
 229   case Bytecodes::_invokeinterface:
 230     return Interpreter::invokeinterface_return_entry_table();
 231   case Bytecodes::_invokedynamic:
 232     return Interpreter::invokedynamic_return_entry_table();
 233   default:
 234     fatal("invalid bytecode: %s", Bytecodes::name(code));
 235     return NULL;
 236   }
 237 }
 238 
 239 /**
 240  * Returns the return entry address for the given top-of-stack state and bytecode.
 241  */
 242 address TemplateInterpreter::return_entry(TosState state, int length, Bytecodes::Code code) {
 243   return return_entry(state, length, code, false);
 244 }
 245 
 246 address TemplateInterpreter::return_entry(TosState state, int length, Bytecodes::Code code, bool X) {
 247   guarantee(0 <= length && length < Interpreter::number_of_return_entries, "illegal length");
 248   const int index = TosState_as_index(state);
 249   switch (code) {
 250   case Bytecodes::_invokestatic:
 251   case Bytecodes::_invokespecial:
 252   case Bytecodes::_invokevirtual:
 253   case Bytecodes::_invokehandle:
 254     return X ? _invoke_return_entryX[index] : _invoke_return_entry[index];
 255   case Bytecodes::_invokeinterface:
 256     return _invokeinterface_return_entry[index];
 257   case Bytecodes::_invokedynamic:
 258     return _invokedynamic_return_entry[index];
 259   default:
 260     assert(!Bytecodes::is_invoke(code), "invoke instructions should be handled separately: %s", Bytecodes::name(code));
 261     address entry = (X ? _return_entryX[length] : _return_entry[length]).entry(state);
 262     vmassert(entry != NULL, "unsupported return entry requested, length=%d state=%d", length, index);
 263     return entry;
 264   }
 265 }
 266 
 267 
 268 address TemplateInterpreter::deopt_entry(TosState state, int length) {
 269   guarantee(0 <= length && length < Interpreter::number_of_deopt_entries, "illegal length");
 270   address entry = _deopt_entry[length].entry(state);
 271   vmassert(entry != NULL, "unsupported deopt entry requested, length=%d state=%d", length, TosState_as_index(state));
 272   return entry;
 273 }
 274 
 275 //------------------------------------------------------------------------------------------------------------------------
 276 // Suport for invokes
 277 
 278 int TemplateInterpreter::TosState_as_index(TosState state) {
 279   assert( state < number_of_states , "Invalid state in TosState_as_index");
 280   assert(0 <= (int)state && (int)state < TemplateInterpreter::number_of_return_addrs, "index out of bounds");
 281   return (int)state;
 282 }
 283 
 284 
 285 //------------------------------------------------------------------------------------------------------------------------
 286 // Safepoint support
 287 
 288 static inline void copy_table(address* from, address* to, int size) {
 289   // Copy non-overlapping tables.
 290   if (SafepointSynchronize::is_at_safepoint()) {
 291     // Nothing is using the table at a safepoint so skip atomic word copy.
 292     Copy::disjoint_words((HeapWord*)from, (HeapWord*)to, (size_t)size);
 293   } else {
 294     // Use atomic word copy when not at a safepoint for safety.
 295     Copy::disjoint_words_atomic((HeapWord*)from, (HeapWord*)to, (size_t)size);
 296   }
 297 }
 298 
 299 void TemplateInterpreter::notice_safepoints() {
 300   if (!_notice_safepoints) {
 301     log_debug(interpreter, safepoint)("switching active_table to safept_table.");
 302     // switch to safepoint dispatch table
 303     _notice_safepoints = true;
 304     copy_table((address*)&_safept_table, (address*)&_active_table, sizeof(_active_table) / sizeof(address));
 305   } else {
 306     log_debug(interpreter, safepoint)("active_table is already safept_table; "
 307                                       "notice_safepoints() call is no-op.");
 308   }
 309 }
 310 
 311 // switch from the dispatch table which notices safepoints back to the
 312 // normal dispatch table.  So that we can notice single stepping points,
 313 // keep the safepoint dispatch table if we are single stepping in JVMTI.
 314 // Note that the should_post_single_step test is exactly as fast as the
 315 // JvmtiExport::_enabled test and covers both cases.
 316 void TemplateInterpreter::ignore_safepoints() {
 317   if (_notice_safepoints) {
 318     if (!JvmtiExport::should_post_single_step()) {
 319       log_debug(interpreter, safepoint)("switching active_table to normal_table.");
 320       // switch to normal dispatch table
 321       _notice_safepoints = false;
 322       copy_table((address*)&_normal_table, (address*)&_active_table, sizeof(_active_table) / sizeof(address));
 323     } else {
 324       log_debug(interpreter, safepoint)("single stepping is still active; "
 325                                         "ignoring ignore_safepoints() call.");
 326     }
 327   } else {
 328     log_debug(interpreter, safepoint)("active_table is already normal_table; "
 329                                       "ignore_safepoints() call is no-op.");
 330   }
 331 }
 332 
 333 //------------------------------------------------------------------------------------------------------------------------
 334 // Deoptimization support
 335 
 336 // If deoptimization happens, this function returns the point of next bytecode to continue execution
 337 address TemplateInterpreter::deopt_continue_after_entry(Method* method, address bcp, int callee_parameters, bool is_top_frame) {
 338   return AbstractInterpreter::deopt_continue_after_entry(method, bcp, callee_parameters, is_top_frame);
 339 }
 340 
 341 // If deoptimization happens, this function returns the point where the interpreter reexecutes
 342 // the bytecode.
 343 // Note: Bytecodes::_athrow (C1 only) and Bytecodes::_return are the special cases
 344 //       that do not return "Interpreter::deopt_entry(vtos, 0)"
 345 address TemplateInterpreter::deopt_reexecute_entry(Method* method, address bcp) {
 346   assert(method->contains(bcp), "just checkin'");
 347   Bytecodes::Code code   = Bytecodes::code_at(method, bcp);
 348   if (code == Bytecodes::_return_register_finalizer) {
 349     // This is used for deopt during registration of finalizers
 350     // during Object.<init>.  We simply need to resume execution at
 351     // the standard return vtos bytecode to pop the frame normally.
 352     // reexecuting the real bytecode would cause double registration
 353     // of the finalizable object.
 354     return Interpreter::deopt_reexecute_return_entry();
 355   } else {
 356     return AbstractInterpreter::deopt_reexecute_entry(method, bcp);
 357   }
 358 }
 359 
 360 // If deoptimization happens, the interpreter should reexecute this bytecode.
 361 // This function mainly helps the compilers to set up the reexecute bit.
 362 bool TemplateInterpreter::bytecode_should_reexecute(Bytecodes::Code code) {
 363   if (code == Bytecodes::_return) {
 364     //Yes, we consider Bytecodes::_return as a special case of reexecution
 365     return true;
 366   } else {
 367     return AbstractInterpreter::bytecode_should_reexecute(code);
 368   }
 369 }
 370 
 371 InterpreterCodelet* TemplateInterpreter::codelet_containing(address pc) {
 372   return (InterpreterCodelet*)_code->stub_containing(pc);
 373 }
 374 
 375 #endif // !CC_INTERP