1 /*
  2  * Copyright (c) 1997, 2022, 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 "prims/jvmtiExport.hpp"
 35 #include "runtime/safepoint.hpp"
 36 #include "runtime/timerTrace.hpp"
 37 #include "utilities/copy.hpp"
 38 
 39 # define __ _masm->
 40 
 41 void TemplateInterpreter::initialize_stub() {
 42   // assertions
 43   assert(_code == NULL, "must only initialize once");
 44   assert((int)Bytecodes::number_of_codes <= (int)DispatchTable::length,
 45          "dispatch table too small");
 46 
 47   // allocate interpreter
 48   int code_size = InterpreterCodeSize;
 49   NOT_PRODUCT(code_size *= 4;)  // debug uses extra interpreter code space
 50   // 270+ interpreter codelets are generated and each of them is required to be aligned to
 51   // CodeEntryAlignment twice. So we need additional size due to alignment.
 52   int max_aligned_codelets = 280;
 53   int max_aligned_bytes = max_aligned_codelets * CodeEntryAlignment * 2;
 54   _code = new StubQueue(new InterpreterCodeletInterface, code_size + max_aligned_bytes, NULL,
 55                         "Interpreter");
 56 }
 57 
 58 void TemplateInterpreter::initialize_code() {
 59   AbstractInterpreter::initialize();
 60 
 61   TemplateTable::initialize();
 62 
 63   // generate interpreter
 64   { ResourceMark rm;
 65     TraceTime timer("Interpreter generation", TRACETIME_LOG(Info, startuptime));
 66     TemplateInterpreterGenerator g(_code);
 67     // Free the unused memory not occupied by the interpreter and the stubs
 68     _code->deallocate_unused_tail();
 69   }
 70 
 71   if (PrintInterpreter) {
 72     ResourceMark rm;
 73     print();
 74   }
 75 
 76   // initialize dispatch table
 77   _active_table = _normal_table;
 78 }
 79 
 80 //------------------------------------------------------------------------------------------------------------------------
 81 // Implementation of EntryPoint
 82 
 83 EntryPoint::EntryPoint() {
 84   assert(number_of_states == 10, "check the code below");
 85   _entry[btos] = NULL;
 86   _entry[ztos] = NULL;
 87   _entry[ctos] = NULL;
 88   _entry[stos] = NULL;
 89   _entry[atos] = NULL;
 90   _entry[itos] = NULL;
 91   _entry[ltos] = NULL;
 92   _entry[ftos] = NULL;
 93   _entry[dtos] = NULL;
 94   _entry[vtos] = NULL;
 95 }
 96 
 97 
 98 EntryPoint::EntryPoint(address bentry, address zentry, address centry, address sentry, address aentry, address ientry, address lentry, address fentry, address dentry, address ventry) {
 99   assert(number_of_states == 10, "check the code below");
100   _entry[btos] = bentry;
101   _entry[ztos] = zentry;
102   _entry[ctos] = centry;
103   _entry[stos] = sentry;
104   _entry[atos] = aentry;
105   _entry[itos] = ientry;
106   _entry[ltos] = lentry;
107   _entry[ftos] = fentry;
108   _entry[dtos] = dentry;
109   _entry[vtos] = ventry;
110 }
111 
112 EntryPoint::EntryPoint(address aentry, address ientry, address lentry, address fentry, address dentry, address ventry) {
113   assert(number_of_states == 10, "check the code below");
114   _entry[btos] = ientry;
115   _entry[ztos] = ientry;
116   _entry[ctos] = ientry;
117   _entry[stos] = ientry;
118   _entry[atos] = aentry;
119   _entry[itos] = ientry;
120   _entry[ltos] = lentry;
121   _entry[ftos] = fentry;
122   _entry[dtos] = dentry;
123   _entry[vtos] = ventry;
124 }
125 
126 void EntryPoint::set_entry(TosState state, address entry) {
127   assert(0 <= state && state < number_of_states, "state out of bounds");
128   _entry[state] = entry;
129 }
130 
131 
132 address EntryPoint::entry(TosState state) const {
133   assert(0 <= state && state < number_of_states, "state out of bounds");
134   return _entry[state];
135 }
136 
137 
138 void EntryPoint::print() {
139   tty->print("[");
140   for (int i = 0; i < number_of_states; i++) {
141     if (i > 0) tty->print(", ");
142     tty->print(INTPTR_FORMAT, p2i(_entry[i]));
143   }
144   tty->print("]");
145 }
146 
147 
148 bool EntryPoint::operator == (const EntryPoint& y) {
149   int i = number_of_states;
150   while (i-- > 0) {
151     if (_entry[i] != y._entry[i]) return false;
152   }
153   return true;
154 }
155 
156 
157 //------------------------------------------------------------------------------------------------------------------------
158 // Implementation of DispatchTable
159 
160 EntryPoint DispatchTable::entry(int i) const {
161   assert(0 <= i && i < length, "index out of bounds");
162   return
163     EntryPoint(
164       _table[btos][i],
165       _table[ztos][i],
166       _table[ctos][i],
167       _table[stos][i],
168       _table[atos][i],
169       _table[itos][i],
170       _table[ltos][i],
171       _table[ftos][i],
172       _table[dtos][i],
173       _table[vtos][i]
174     );
175 }
176 
177 
178 void DispatchTable::set_entry(int i, EntryPoint& entry) {
179   assert(0 <= i && i < length, "index out of bounds");
180   assert(number_of_states == 10, "check the code below");
181   _table[btos][i] = entry.entry(btos);
182   _table[ztos][i] = entry.entry(ztos);
183   _table[ctos][i] = entry.entry(ctos);
184   _table[stos][i] = entry.entry(stos);
185   _table[atos][i] = entry.entry(atos);
186   _table[itos][i] = entry.entry(itos);
187   _table[ltos][i] = entry.entry(ltos);
188   _table[ftos][i] = entry.entry(ftos);
189   _table[dtos][i] = entry.entry(dtos);
190   _table[vtos][i] = entry.entry(vtos);
191 }
192 
193 
194 bool DispatchTable::operator == (DispatchTable& y) {
195   int i = length;
196   while (i-- > 0) {
197     EntryPoint t = y.entry(i); // for compiler compatibility (BugId 4150096)
198     if (!(entry(i) == t)) return false;
199   }
200   return true;
201 }
202 
203 address    TemplateInterpreter::_remove_activation_entry                    = NULL;
204 address    TemplateInterpreter::_remove_activation_preserving_args_entry    = NULL;
205 
206 
207 address    TemplateInterpreter::_throw_ArrayIndexOutOfBoundsException_entry = NULL;
208 address    TemplateInterpreter::_throw_ArrayStoreException_entry            = NULL;
209 address    TemplateInterpreter::_throw_ArithmeticException_entry            = NULL;
210 address    TemplateInterpreter::_throw_ClassCastException_entry             = NULL;
211 address    TemplateInterpreter::_throw_NullPointerException_entry           = NULL;
212 address    TemplateInterpreter::_throw_StackOverflowError_entry             = NULL;
213 address    TemplateInterpreter::_throw_exception_entry                      = NULL;
214 
215 #ifndef PRODUCT
216 EntryPoint TemplateInterpreter::_trace_code;
217 #endif // !PRODUCT
218 EntryPoint TemplateInterpreter::_return_entry[TemplateInterpreter::number_of_return_entries];
219 EntryPoint TemplateInterpreter::_earlyret_entry;
220 EntryPoint TemplateInterpreter::_deopt_entry [TemplateInterpreter::number_of_deopt_entries ];
221 address    TemplateInterpreter::_deopt_reexecute_return_entry;
222 EntryPoint TemplateInterpreter::_safept_entry;
223 
224 address TemplateInterpreter::_invoke_return_entry[TemplateInterpreter::number_of_return_addrs];
225 address TemplateInterpreter::_invokeinterface_return_entry[TemplateInterpreter::number_of_return_addrs];
226 address TemplateInterpreter::_invokedynamic_return_entry[TemplateInterpreter::number_of_return_addrs];
227 
228 DispatchTable TemplateInterpreter::_active_table;
229 DispatchTable TemplateInterpreter::_normal_table;
230 DispatchTable TemplateInterpreter::_safept_table;
231 address    TemplateInterpreter::_wentry_point[DispatchTable::length];
232 
233 
234 //------------------------------------------------------------------------------------------------------------------------
235 // Entry points
236 
237 /**
238  * Returns the return entry table for the given invoke bytecode.
239  */
240 address* TemplateInterpreter::invoke_return_entry_table_for(Bytecodes::Code code) {
241   switch (code) {
242   case Bytecodes::_invokestatic:
243   case Bytecodes::_invokespecial:
244   case Bytecodes::_invokevirtual:
245   case Bytecodes::_invokehandle:
246     return Interpreter::invoke_return_entry_table();
247   case Bytecodes::_invokeinterface:
248     return Interpreter::invokeinterface_return_entry_table();
249   case Bytecodes::_invokedynamic:
250     return Interpreter::invokedynamic_return_entry_table();
251   default:
252     fatal("invalid bytecode: %s", Bytecodes::name(code));
253     return NULL;
254   }
255 }
256 
257 /**
258  * Returns the return entry address for the given top-of-stack state and bytecode.
259  */
260 address TemplateInterpreter::return_entry(TosState state, int length, Bytecodes::Code code) {
261   guarantee(0 <= length && length < Interpreter::number_of_return_entries, "illegal length");
262   const int index = TosState_as_index(state);
263   switch (code) {
264   case Bytecodes::_invokestatic:
265   case Bytecodes::_invokespecial:
266   case Bytecodes::_invokevirtual:
267   case Bytecodes::_invokehandle:
268     return _invoke_return_entry[index];
269   case Bytecodes::_invokeinterface:
270     return _invokeinterface_return_entry[index];
271   case Bytecodes::_invokedynamic:
272     return _invokedynamic_return_entry[index];
273   default:
274     assert(!Bytecodes::is_invoke(code), "invoke instructions should be handled separately: %s", Bytecodes::name(code));
275     address entry = _return_entry[length].entry(state);
276     vmassert(entry != NULL, "unsupported return entry requested, length=%d state=%d", length, index);
277     return entry;
278   }
279 }
280 
281 
282 address TemplateInterpreter::deopt_entry(TosState state, int length) {
283   guarantee(0 <= length && length < Interpreter::number_of_deopt_entries, "illegal length");
284   address entry = _deopt_entry[length].entry(state);
285   vmassert(entry != NULL, "unsupported deopt entry requested, length=%d state=%d", length, TosState_as_index(state));
286   return entry;
287 }
288 
289 //------------------------------------------------------------------------------------------------------------------------
290 // Suport for invokes
291 
292 int TemplateInterpreter::TosState_as_index(TosState state) {
293   assert( state < number_of_states , "Invalid state in TosState_as_index");
294   assert(0 <= (int)state && (int)state < TemplateInterpreter::number_of_return_addrs, "index out of bounds");
295   return (int)state;
296 }
297 
298 
299 //------------------------------------------------------------------------------------------------------------------------
300 // Safepoint support
301 
302 static inline void copy_table(address* from, address* to, int size) {
303   // Copy non-overlapping tables.
304   if (SafepointSynchronize::is_at_safepoint()) {
305     // Nothing is using the table at a safepoint so skip atomic word copy.
306     Copy::disjoint_words((HeapWord*)from, (HeapWord*)to, (size_t)size);
307   } else {
308     // Use atomic word copy when not at a safepoint for safety.
309     Copy::disjoint_words_atomic((HeapWord*)from, (HeapWord*)to, (size_t)size);
310   }
311 }
312 
313 void TemplateInterpreter::notice_safepoints() {
314   if (!_notice_safepoints) {
315     log_debug(interpreter, safepoint)("switching active_table to safept_table.");
316     // switch to safepoint dispatch table
317     _notice_safepoints = true;
318     copy_table((address*)&_safept_table, (address*)&_active_table, sizeof(_active_table) / sizeof(address));
319   } else {
320     log_debug(interpreter, safepoint)("active_table is already safept_table; "
321                                       "notice_safepoints() call is no-op.");
322   }
323 }
324 
325 // switch from the dispatch table which notices safepoints back to the
326 // normal dispatch table.  So that we can notice single stepping points,
327 // keep the safepoint dispatch table if we are single stepping in JVMTI.
328 // Note that the should_post_single_step test is exactly as fast as the
329 // JvmtiExport::_enabled test and covers both cases.
330 void TemplateInterpreter::ignore_safepoints() {
331   if (_notice_safepoints) {
332     if (!JvmtiExport::should_post_single_step()) {
333       log_debug(interpreter, safepoint)("switching active_table to normal_table.");
334       // switch to normal dispatch table
335       _notice_safepoints = false;
336       copy_table((address*)&_normal_table, (address*)&_active_table, sizeof(_active_table) / sizeof(address));
337     } else {
338       log_debug(interpreter, safepoint)("single stepping is still active; "
339                                         "ignoring ignore_safepoints() call.");
340     }
341   } else {
342     log_debug(interpreter, safepoint)("active_table is already normal_table; "
343                                       "ignore_safepoints() call is no-op.");
344   }
345 }
346 
347 //------------------------------------------------------------------------------------------------------------------------
348 // Deoptimization support
349 
350 // If deoptimization happens, this function returns the point of next bytecode to continue execution
351 address TemplateInterpreter::deopt_continue_after_entry(Method* method, address bcp, int callee_parameters, bool is_top_frame) {
352   return AbstractInterpreter::deopt_continue_after_entry(method, bcp, callee_parameters, is_top_frame);
353 }
354 
355 // If deoptimization happens, this function returns the point where the interpreter reexecutes
356 // the bytecode.
357 // Note: Bytecodes::_athrow (C1 only) and Bytecodes::_return are the special cases
358 //       that do not return "Interpreter::deopt_entry(vtos, 0)"
359 address TemplateInterpreter::deopt_reexecute_entry(Method* method, address bcp) {
360   assert(method->contains(bcp), "just checkin'");
361   Bytecodes::Code code   = Bytecodes::code_at(method, bcp);
362   if (code == Bytecodes::_return_register_finalizer) {
363     // This is used for deopt during registration of finalizers
364     // during Object.<init>.  We simply need to resume execution at
365     // the standard return vtos bytecode to pop the frame normally.
366     // reexecuting the real bytecode would cause double registration
367     // of the finalizable object.
368     return Interpreter::deopt_reexecute_return_entry();
369   } else {
370     return AbstractInterpreter::deopt_reexecute_entry(method, bcp);
371   }
372 }
373 
374 // If deoptimization happens, the interpreter should reexecute this bytecode.
375 // This function mainly helps the compilers to set up the reexecute bit.
376 bool TemplateInterpreter::bytecode_should_reexecute(Bytecodes::Code code) {
377   if (code == Bytecodes::_return) {
378     //Yes, we consider Bytecodes::_return as a special case of reexecution
379     return true;
380   } else {
381     return AbstractInterpreter::bytecode_should_reexecute(code);
382   }
383 }
384 
385 InterpreterCodelet* TemplateInterpreter::codelet_containing(address pc) {
386   return (InterpreterCodelet*)_code->stub_containing(pc);
387 }