1 /*
2 * Copyright 2001-2009 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/_graphKit.cpp.incl"
27
28 //----------------------------GraphKit-----------------------------------------
29 // Main utility constructor.
30 GraphKit::GraphKit(JVMState* jvms)
31 : Phase(Phase::Parser),
32 _env(C->env()),
33 _gvn(*C->initial_gvn())
34 {
35 _exceptions = jvms->map()->next_exception();
36 if (_exceptions != NULL) jvms->map()->set_next_exception(NULL);
37 set_jvms(jvms);
38 }
39
40 // Private constructor for parser.
41 GraphKit::GraphKit()
42 : Phase(Phase::Parser),
43 _env(C->env()),
44 _gvn(*C->initial_gvn())
45 {
46 _exceptions = NULL;
47 set_map(NULL);
48 debug_only(_sp = -99);
49 debug_only(set_bci(-99));
50 }
51
52
53
54 //---------------------------clean_stack---------------------------------------
55 // Clear away rubbish from the stack area of the JVM state.
56 // This destroys any arguments that may be waiting on the stack.
57 void GraphKit::clean_stack(int from_sp) {
58 SafePointNode* map = this->map();
59 JVMState* jvms = this->jvms();
60 int stk_size = jvms->stk_size();
61 int stkoff = jvms->stkoff();
62 Node* top = this->top();
63 for (int i = from_sp; i < stk_size; i++) {
64 if (map->in(stkoff + i) != top) {
65 map->set_req(stkoff + i, top);
66 }
67 }
68 }
69
70
71 //--------------------------------sync_jvms-----------------------------------
72 // Make sure our current jvms agrees with our parse state.
73 JVMState* GraphKit::sync_jvms() const {
74 JVMState* jvms = this->jvms();
75 jvms->set_bci(bci()); // Record the new bci in the JVMState
76 jvms->set_sp(sp()); // Record the new sp in the JVMState
77 assert(jvms_in_sync(), "jvms is now in sync");
78 return jvms;
79 }
80
81 #ifdef ASSERT
82 bool GraphKit::jvms_in_sync() const {
83 Parse* parse = is_Parse();
84 if (parse == NULL) {
85 if (bci() != jvms()->bci()) return false;
86 if (sp() != (int)jvms()->sp()) return false;
87 return true;
88 }
89 if (jvms()->method() != parse->method()) return false;
90 if (jvms()->bci() != parse->bci()) return false;
91 int jvms_sp = jvms()->sp();
92 if (jvms_sp != parse->sp()) return false;
93 int jvms_depth = jvms()->depth();
94 if (jvms_depth != parse->depth()) return false;
95 return true;
96 }
97
98 // Local helper checks for special internal merge points
99 // used to accumulate and merge exception states.
100 // They are marked by the region's in(0) edge being the map itself.
101 // Such merge points must never "escape" into the parser at large,
102 // until they have been handed to gvn.transform.
103 static bool is_hidden_merge(Node* reg) {
104 if (reg == NULL) return false;
105 if (reg->is_Phi()) {
106 reg = reg->in(0);
107 if (reg == NULL) return false;
108 }
109 return reg->is_Region() && reg->in(0) != NULL && reg->in(0)->is_Root();
110 }
111
112 void GraphKit::verify_map() const {
113 if (map() == NULL) return; // null map is OK
114 assert(map()->req() <= jvms()->endoff(), "no extra garbage on map");
115 assert(!map()->has_exceptions(), "call add_exception_states_from 1st");
116 assert(!is_hidden_merge(control()), "call use_exception_state, not set_map");
117 }
118
119 void GraphKit::verify_exception_state(SafePointNode* ex_map) {
120 assert(ex_map->next_exception() == NULL, "not already part of a chain");
121 assert(has_saved_ex_oop(ex_map), "every exception state has an ex_oop");
122 }
123 #endif
124
125 //---------------------------stop_and_kill_map---------------------------------
126 // Set _map to NULL, signalling a stop to further bytecode execution.
127 // First smash the current map's control to a constant, to mark it dead.
128 void GraphKit::stop_and_kill_map() {
129 SafePointNode* dead_map = stop();
130 if (dead_map != NULL) {
131 dead_map->disconnect_inputs(NULL); // Mark the map as killed.
132 assert(dead_map->is_killed(), "must be so marked");
133 }
134 }
135
136
137 //--------------------------------stopped--------------------------------------
138 // Tell if _map is NULL, or control is top.
139 bool GraphKit::stopped() {
140 if (map() == NULL) return true;
141 else if (control() == top()) return true;
142 else return false;
143 }
144
145
146 //-----------------------------has_ex_handler----------------------------------
147 // Tell if this method or any caller method has exception handlers.
148 bool GraphKit::has_ex_handler() {
149 for (JVMState* jvmsp = jvms(); jvmsp != NULL; jvmsp = jvmsp->caller()) {
150 if (jvmsp->has_method() && jvmsp->method()->has_exception_handlers()) {
151 return true;
152 }
153 }
154 return false;
155 }
156
157 //------------------------------save_ex_oop------------------------------------
158 // Save an exception without blowing stack contents or other JVM state.
159 void GraphKit::set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop) {
160 assert(!has_saved_ex_oop(ex_map), "clear ex-oop before setting again");
161 ex_map->add_req(ex_oop);
162 debug_only(verify_exception_state(ex_map));
163 }
164
165 inline static Node* common_saved_ex_oop(SafePointNode* ex_map, bool clear_it) {
166 assert(GraphKit::has_saved_ex_oop(ex_map), "ex_oop must be there");
167 Node* ex_oop = ex_map->in(ex_map->req()-1);
168 if (clear_it) ex_map->del_req(ex_map->req()-1);
169 return ex_oop;
170 }
171
172 //-----------------------------saved_ex_oop------------------------------------
173 // Recover a saved exception from its map.
174 Node* GraphKit::saved_ex_oop(SafePointNode* ex_map) {
175 return common_saved_ex_oop(ex_map, false);
176 }
177
178 //--------------------------clear_saved_ex_oop---------------------------------
179 // Erase a previously saved exception from its map.
180 Node* GraphKit::clear_saved_ex_oop(SafePointNode* ex_map) {
181 return common_saved_ex_oop(ex_map, true);
182 }
183
184 #ifdef ASSERT
185 //---------------------------has_saved_ex_oop----------------------------------
186 // Erase a previously saved exception from its map.
187 bool GraphKit::has_saved_ex_oop(SafePointNode* ex_map) {
188 return ex_map->req() == ex_map->jvms()->endoff()+1;
189 }
190 #endif
191
192 //-------------------------make_exception_state--------------------------------
193 // Turn the current JVM state into an exception state, appending the ex_oop.
194 SafePointNode* GraphKit::make_exception_state(Node* ex_oop) {
195 sync_jvms();
196 SafePointNode* ex_map = stop(); // do not manipulate this map any more
197 set_saved_ex_oop(ex_map, ex_oop);
198 return ex_map;
199 }
200
201
202 //--------------------------add_exception_state--------------------------------
203 // Add an exception to my list of exceptions.
204 void GraphKit::add_exception_state(SafePointNode* ex_map) {
205 if (ex_map == NULL || ex_map->control() == top()) {
206 return;
207 }
208 #ifdef ASSERT
209 verify_exception_state(ex_map);
210 if (has_exceptions()) {
211 assert(ex_map->jvms()->same_calls_as(_exceptions->jvms()), "all collected exceptions must come from the same place");
212 }
213 #endif
214
215 // If there is already an exception of exactly this type, merge with it.
216 // In particular, null-checks and other low-level exceptions common up here.
217 Node* ex_oop = saved_ex_oop(ex_map);
218 const Type* ex_type = _gvn.type(ex_oop);
219 if (ex_oop == top()) {
220 // No action needed.
221 return;
222 }
223 assert(ex_type->isa_instptr(), "exception must be an instance");
224 for (SafePointNode* e2 = _exceptions; e2 != NULL; e2 = e2->next_exception()) {
225 const Type* ex_type2 = _gvn.type(saved_ex_oop(e2));
226 // We check sp also because call bytecodes can generate exceptions
227 // both before and after arguments are popped!
228 if (ex_type2 == ex_type
229 && e2->_jvms->sp() == ex_map->_jvms->sp()) {
230 combine_exception_states(ex_map, e2);
231 return;
232 }
233 }
234
235 // No pre-existing exception of the same type. Chain it on the list.
236 push_exception_state(ex_map);
237 }
238
239 //-----------------------add_exception_states_from-----------------------------
240 void GraphKit::add_exception_states_from(JVMState* jvms) {
241 SafePointNode* ex_map = jvms->map()->next_exception();
242 if (ex_map != NULL) {
243 jvms->map()->set_next_exception(NULL);
244 for (SafePointNode* next_map; ex_map != NULL; ex_map = next_map) {
245 next_map = ex_map->next_exception();
246 ex_map->set_next_exception(NULL);
247 add_exception_state(ex_map);
248 }
249 }
250 }
251
252 //-----------------------transfer_exceptions_into_jvms-------------------------
253 JVMState* GraphKit::transfer_exceptions_into_jvms() {
254 if (map() == NULL) {
255 // We need a JVMS to carry the exceptions, but the map has gone away.
256 // Create a scratch JVMS, cloned from any of the exception states...
257 if (has_exceptions()) {
258 _map = _exceptions;
259 _map = clone_map();
260 _map->set_next_exception(NULL);
261 clear_saved_ex_oop(_map);
262 debug_only(verify_map());
263 } else {
264 // ...or created from scratch
265 JVMState* jvms = new (C) JVMState(_method, NULL);
266 jvms->set_bci(_bci);
267 jvms->set_sp(_sp);
268 jvms->set_map(new (C, TypeFunc::Parms) SafePointNode(TypeFunc::Parms, jvms));
269 set_jvms(jvms);
270 for (uint i = 0; i < map()->req(); i++) map()->init_req(i, top());
271 set_all_memory(top());
272 while (map()->req() < jvms->endoff()) map()->add_req(top());
273 }
274 // (This is a kludge, in case you didn't notice.)
275 set_control(top());
276 }
277 JVMState* jvms = sync_jvms();
278 assert(!jvms->map()->has_exceptions(), "no exceptions on this map yet");
279 jvms->map()->set_next_exception(_exceptions);
280 _exceptions = NULL; // done with this set of exceptions
281 return jvms;
282 }
283
284 static inline void add_n_reqs(Node* dstphi, Node* srcphi) {
285 assert(is_hidden_merge(dstphi), "must be a special merge node");
286 assert(is_hidden_merge(srcphi), "must be a special merge node");
287 uint limit = srcphi->req();
288 for (uint i = PhiNode::Input; i < limit; i++) {
289 dstphi->add_req(srcphi->in(i));
290 }
291 }
292 static inline void add_one_req(Node* dstphi, Node* src) {
293 assert(is_hidden_merge(dstphi), "must be a special merge node");
294 assert(!is_hidden_merge(src), "must not be a special merge node");
295 dstphi->add_req(src);
296 }
297
298 //-----------------------combine_exception_states------------------------------
299 // This helper function combines exception states by building phis on a
300 // specially marked state-merging region. These regions and phis are
301 // untransformed, and can build up gradually. The region is marked by
302 // having a control input of its exception map, rather than NULL. Such
303 // regions do not appear except in this function, and in use_exception_state.
304 void GraphKit::combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map) {
305 if (failing()) return; // dying anyway...
306 JVMState* ex_jvms = ex_map->_jvms;
307 assert(ex_jvms->same_calls_as(phi_map->_jvms), "consistent call chains");
308 assert(ex_jvms->stkoff() == phi_map->_jvms->stkoff(), "matching locals");
309 assert(ex_jvms->sp() == phi_map->_jvms->sp(), "matching stack sizes");
310 assert(ex_jvms->monoff() == phi_map->_jvms->monoff(), "matching JVMS");
311 assert(ex_map->req() == phi_map->req(), "matching maps");
312 uint tos = ex_jvms->stkoff() + ex_jvms->sp();
313 Node* hidden_merge_mark = root();
314 Node* region = phi_map->control();
315 MergeMemNode* phi_mem = phi_map->merged_memory();
316 MergeMemNode* ex_mem = ex_map->merged_memory();
317 if (region->in(0) != hidden_merge_mark) {
318 // The control input is not (yet) a specially-marked region in phi_map.
319 // Make it so, and build some phis.
320 region = new (C, 2) RegionNode(2);
321 _gvn.set_type(region, Type::CONTROL);
322 region->set_req(0, hidden_merge_mark); // marks an internal ex-state
323 region->init_req(1, phi_map->control());
324 phi_map->set_control(region);
325 Node* io_phi = PhiNode::make(region, phi_map->i_o(), Type::ABIO);
326 record_for_igvn(io_phi);
327 _gvn.set_type(io_phi, Type::ABIO);
328 phi_map->set_i_o(io_phi);
329 for (MergeMemStream mms(phi_mem); mms.next_non_empty(); ) {
330 Node* m = mms.memory();
331 Node* m_phi = PhiNode::make(region, m, Type::MEMORY, mms.adr_type(C));
332 record_for_igvn(m_phi);
333 _gvn.set_type(m_phi, Type::MEMORY);
334 mms.set_memory(m_phi);
335 }
336 }
337
338 // Either or both of phi_map and ex_map might already be converted into phis.
339 Node* ex_control = ex_map->control();
340 // if there is special marking on ex_map also, we add multiple edges from src
341 bool add_multiple = (ex_control->in(0) == hidden_merge_mark);
342 // how wide was the destination phi_map, originally?
343 uint orig_width = region->req();
344
345 if (add_multiple) {
346 add_n_reqs(region, ex_control);
347 add_n_reqs(phi_map->i_o(), ex_map->i_o());
348 } else {
349 // ex_map has no merges, so we just add single edges everywhere
350 add_one_req(region, ex_control);
351 add_one_req(phi_map->i_o(), ex_map->i_o());
352 }
353 for (MergeMemStream mms(phi_mem, ex_mem); mms.next_non_empty2(); ) {
354 if (mms.is_empty()) {
355 // get a copy of the base memory, and patch some inputs into it
356 const TypePtr* adr_type = mms.adr_type(C);
357 Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
358 assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
359 mms.set_memory(phi);
360 // Prepare to append interesting stuff onto the newly sliced phi:
361 while (phi->req() > orig_width) phi->del_req(phi->req()-1);
362 }
363 // Append stuff from ex_map:
364 if (add_multiple) {
365 add_n_reqs(mms.memory(), mms.memory2());
366 } else {
367 add_one_req(mms.memory(), mms.memory2());
368 }
369 }
370 uint limit = ex_map->req();
371 for (uint i = TypeFunc::Parms; i < limit; i++) {
372 // Skip everything in the JVMS after tos. (The ex_oop follows.)
373 if (i == tos) i = ex_jvms->monoff();
374 Node* src = ex_map->in(i);
375 Node* dst = phi_map->in(i);
376 if (src != dst) {
377 PhiNode* phi;
378 if (dst->in(0) != region) {
379 dst = phi = PhiNode::make(region, dst, _gvn.type(dst));
380 record_for_igvn(phi);
381 _gvn.set_type(phi, phi->type());
382 phi_map->set_req(i, dst);
383 // Prepare to append interesting stuff onto the new phi:
384 while (dst->req() > orig_width) dst->del_req(dst->req()-1);
385 } else {
386 assert(dst->is_Phi(), "nobody else uses a hidden region");
387 phi = (PhiNode*)dst;
388 }
389 if (add_multiple && src->in(0) == ex_control) {
390 // Both are phis.
391 add_n_reqs(dst, src);
392 } else {
393 while (dst->req() < region->req()) add_one_req(dst, src);
394 }
395 const Type* srctype = _gvn.type(src);
396 if (phi->type() != srctype) {
397 const Type* dsttype = phi->type()->meet(srctype);
398 if (phi->type() != dsttype) {
399 phi->set_type(dsttype);
400 _gvn.set_type(phi, dsttype);
401 }
402 }
403 }
404 }
405 }
406
407 //--------------------------use_exception_state--------------------------------
408 Node* GraphKit::use_exception_state(SafePointNode* phi_map) {
409 if (failing()) { stop(); return top(); }
410 Node* region = phi_map->control();
411 Node* hidden_merge_mark = root();
412 assert(phi_map->jvms()->map() == phi_map, "sanity: 1-1 relation");
413 Node* ex_oop = clear_saved_ex_oop(phi_map);
414 if (region->in(0) == hidden_merge_mark) {
415 // Special marking for internal ex-states. Process the phis now.
416 region->set_req(0, region); // now it's an ordinary region
417 set_jvms(phi_map->jvms()); // ...so now we can use it as a map
418 // Note: Setting the jvms also sets the bci and sp.
419 set_control(_gvn.transform(region));
420 uint tos = jvms()->stkoff() + sp();
421 for (uint i = 1; i < tos; i++) {
422 Node* x = phi_map->in(i);
423 if (x->in(0) == region) {
424 assert(x->is_Phi(), "expected a special phi");
425 phi_map->set_req(i, _gvn.transform(x));
426 }
427 }
428 for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
429 Node* x = mms.memory();
430 if (x->in(0) == region) {
431 assert(x->is_Phi(), "nobody else uses a hidden region");
432 mms.set_memory(_gvn.transform(x));
433 }
434 }
435 if (ex_oop->in(0) == region) {
436 assert(ex_oop->is_Phi(), "expected a special phi");
437 ex_oop = _gvn.transform(ex_oop);
438 }
439 } else {
440 set_jvms(phi_map->jvms());
441 }
442
443 assert(!is_hidden_merge(phi_map->control()), "hidden ex. states cleared");
444 assert(!is_hidden_merge(phi_map->i_o()), "hidden ex. states cleared");
445 return ex_oop;
446 }
447
448 //---------------------------------java_bc-------------------------------------
449 Bytecodes::Code GraphKit::java_bc() const {
450 ciMethod* method = this->method();
451 int bci = this->bci();
452 if (method != NULL && bci != InvocationEntryBci)
453 return method->java_code_at_bci(bci);
454 else
455 return Bytecodes::_illegal;
456 }
457
458 //------------------------------builtin_throw----------------------------------
459 void GraphKit::builtin_throw(Deoptimization::DeoptReason reason, Node* arg) {
460 bool must_throw = true;
461
462 if (env()->jvmti_can_post_exceptions()) {
463 // Do not try anything fancy if we're notifying the VM on every throw.
464 // Cf. case Bytecodes::_athrow in parse2.cpp.
465 uncommon_trap(reason, Deoptimization::Action_none,
466 (ciKlass*)NULL, (char*)NULL, must_throw);
467 return;
468 }
469
470 // If this particular condition has not yet happened at this
471 // bytecode, then use the uncommon trap mechanism, and allow for
472 // a future recompilation if several traps occur here.
473 // If the throw is hot, try to use a more complicated inline mechanism
474 // which keeps execution inside the compiled code.
475 bool treat_throw_as_hot = false;
476 ciMethodData* md = method()->method_data();
477
478 if (ProfileTraps) {
479 if (too_many_traps(reason)) {
480 treat_throw_as_hot = true;
481 }
482 // (If there is no MDO at all, assume it is early in
483 // execution, and that any deopts are part of the
484 // startup transient, and don't need to be remembered.)
485
486 // Also, if there is a local exception handler, treat all throws
487 // as hot if there has been at least one in this method.
488 if (C->trap_count(reason) != 0
489 && method()->method_data()->trap_count(reason) != 0
490 && has_ex_handler()) {
491 treat_throw_as_hot = true;
492 }
493 }
494
495 // If this throw happens frequently, an uncommon trap might cause
496 // a performance pothole. If there is a local exception handler,
497 // and if this particular bytecode appears to be deoptimizing often,
498 // let us handle the throw inline, with a preconstructed instance.
499 // Note: If the deopt count has blown up, the uncommon trap
500 // runtime is going to flush this nmethod, not matter what.
501 if (treat_throw_as_hot
502 && (!StackTraceInThrowable || OmitStackTraceInFastThrow)) {
503 // If the throw is local, we use a pre-existing instance and
504 // punt on the backtrace. This would lead to a missing backtrace
505 // (a repeat of 4292742) if the backtrace object is ever asked
506 // for its backtrace.
507 // Fixing this remaining case of 4292742 requires some flavor of
508 // escape analysis. Leave that for the future.
509 ciInstance* ex_obj = NULL;
510 switch (reason) {
511 case Deoptimization::Reason_null_check:
512 ex_obj = env()->NullPointerException_instance();
513 break;
514 case Deoptimization::Reason_div0_check:
515 ex_obj = env()->ArithmeticException_instance();
516 break;
517 case Deoptimization::Reason_range_check:
518 ex_obj = env()->ArrayIndexOutOfBoundsException_instance();
519 break;
520 case Deoptimization::Reason_class_check:
521 if (java_bc() == Bytecodes::_aastore) {
522 ex_obj = env()->ArrayStoreException_instance();
523 } else {
524 ex_obj = env()->ClassCastException_instance();
525 }
526 break;
527 }
528 if (failing()) { stop(); return; } // exception allocation might fail
529 if (ex_obj != NULL) {
530 // Cheat with a preallocated exception object.
531 if (C->log() != NULL)
532 C->log()->elem("hot_throw preallocated='1' reason='%s'",
533 Deoptimization::trap_reason_name(reason));
534 const TypeInstPtr* ex_con = TypeInstPtr::make(ex_obj);
535 Node* ex_node = _gvn.transform( ConNode::make(C, ex_con) );
536
537 // Clear the detail message of the preallocated exception object.
538 // Weblogic sometimes mutates the detail message of exceptions
539 // using reflection.
540 int offset = java_lang_Throwable::get_detailMessage_offset();
541 const TypePtr* adr_typ = ex_con->add_offset(offset);
542
543 Node *adr = basic_plus_adr(ex_node, ex_node, offset);
544 Node *store = store_oop_to_object(control(), ex_node, adr, adr_typ, null(), ex_con, T_OBJECT);
545
546 add_exception_state(make_exception_state(ex_node));
547 return;
548 }
549 }
550
551 // %%% Maybe add entry to OptoRuntime which directly throws the exc.?
552 // It won't be much cheaper than bailing to the interp., since we'll
553 // have to pass up all the debug-info, and the runtime will have to
554 // create the stack trace.
555
556 // Usual case: Bail to interpreter.
557 // Reserve the right to recompile if we haven't seen anything yet.
558
559 Deoptimization::DeoptAction action = Deoptimization::Action_maybe_recompile;
560 if (treat_throw_as_hot
561 && (method()->method_data()->trap_recompiled_at(bci())
562 || C->too_many_traps(reason))) {
563 // We cannot afford to take more traps here. Suffer in the interpreter.
564 if (C->log() != NULL)
565 C->log()->elem("hot_throw preallocated='0' reason='%s' mcount='%d'",
566 Deoptimization::trap_reason_name(reason),
567 C->trap_count(reason));
568 action = Deoptimization::Action_none;
569 }
570
571 // "must_throw" prunes the JVM state to include only the stack, if there
572 // are no local exception handlers. This should cut down on register
573 // allocation time and code size, by drastically reducing the number
574 // of in-edges on the call to the uncommon trap.
575
576 uncommon_trap(reason, action, (ciKlass*)NULL, (char*)NULL, must_throw);
577 }
578
579
580 //----------------------------PreserveJVMState---------------------------------
581 PreserveJVMState::PreserveJVMState(GraphKit* kit, bool clone_map) {
582 debug_only(kit->verify_map());
583 _kit = kit;
584 _map = kit->map(); // preserve the map
585 _sp = kit->sp();
586 kit->set_map(clone_map ? kit->clone_map() : NULL);
587 #ifdef ASSERT
588 _bci = kit->bci();
589 Parse* parser = kit->is_Parse();
590 int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo();
591 _block = block;
592 #endif
593 }
594 PreserveJVMState::~PreserveJVMState() {
595 GraphKit* kit = _kit;
596 #ifdef ASSERT
597 assert(kit->bci() == _bci, "bci must not shift");
598 Parse* parser = kit->is_Parse();
599 int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo();
600 assert(block == _block, "block must not shift");
601 #endif
602 kit->set_map(_map);
603 kit->set_sp(_sp);
604 }
605
606
607 //-----------------------------BuildCutout-------------------------------------
608 BuildCutout::BuildCutout(GraphKit* kit, Node* p, float prob, float cnt)
609 : PreserveJVMState(kit)
610 {
611 assert(p->is_Con() || p->is_Bool(), "test must be a bool");
612 SafePointNode* outer_map = _map; // preserved map is caller's
613 SafePointNode* inner_map = kit->map();
614 IfNode* iff = kit->create_and_map_if(outer_map->control(), p, prob, cnt);
615 outer_map->set_control(kit->gvn().transform( new (kit->C, 1) IfTrueNode(iff) ));
616 inner_map->set_control(kit->gvn().transform( new (kit->C, 1) IfFalseNode(iff) ));
617 }
618 BuildCutout::~BuildCutout() {
619 GraphKit* kit = _kit;
620 assert(kit->stopped(), "cutout code must stop, throw, return, etc.");
621 }
622
623 //---------------------------PreserveReexecuteState----------------------------
624 PreserveReexecuteState::PreserveReexecuteState(GraphKit* kit) {
625 _kit = kit;
626 _sp = kit->sp();
627 _reexecute = kit->jvms()->_reexecute;
628 }
629 PreserveReexecuteState::~PreserveReexecuteState() {
630 _kit->jvms()->_reexecute = _reexecute;
631 _kit->set_sp(_sp);
632 }
633
634 //------------------------------clone_map--------------------------------------
635 // Implementation of PreserveJVMState
636 //
637 // Only clone_map(...) here. If this function is only used in the
638 // PreserveJVMState class we may want to get rid of this extra
639 // function eventually and do it all there.
640
641 SafePointNode* GraphKit::clone_map() {
642 if (map() == NULL) return NULL;
643
644 // Clone the memory edge first
645 Node* mem = MergeMemNode::make(C, map()->memory());
646 gvn().set_type_bottom(mem);
647
648 SafePointNode *clonemap = (SafePointNode*)map()->clone();
649 JVMState* jvms = this->jvms();
650 JVMState* clonejvms = jvms->clone_shallow(C);
651 clonemap->set_memory(mem);
652 clonemap->set_jvms(clonejvms);
653 clonejvms->set_map(clonemap);
654 record_for_igvn(clonemap);
655 gvn().set_type_bottom(clonemap);
656 return clonemap;
657 }
658
659
660 //-----------------------------set_map_clone-----------------------------------
661 void GraphKit::set_map_clone(SafePointNode* m) {
662 _map = m;
663 _map = clone_map();
664 _map->set_next_exception(NULL);
665 debug_only(verify_map());
666 }
667
668
669 //----------------------------kill_dead_locals---------------------------------
670 // Detect any locals which are known to be dead, and force them to top.
671 void GraphKit::kill_dead_locals() {
672 // Consult the liveness information for the locals. If any
673 // of them are unused, then they can be replaced by top(). This
674 // should help register allocation time and cut down on the size
675 // of the deoptimization information.
676
677 // This call is made from many of the bytecode handling
678 // subroutines called from the Big Switch in do_one_bytecode.
679 // Every bytecode which might include a slow path is responsible
680 // for killing its dead locals. The more consistent we
681 // are about killing deads, the fewer useless phis will be
682 // constructed for them at various merge points.
683
684 // bci can be -1 (InvocationEntryBci). We return the entry
685 // liveness for the method.
686
687 if (method() == NULL || method()->code_size() == 0) {
688 // We are building a graph for a call to a native method.
689 // All locals are live.
690 return;
691 }
692
693 ResourceMark rm;
694
695 // Consult the liveness information for the locals. If any
696 // of them are unused, then they can be replaced by top(). This
697 // should help register allocation time and cut down on the size
698 // of the deoptimization information.
699 MethodLivenessResult live_locals = method()->liveness_at_bci(bci());
700
701 int len = (int)live_locals.size();
702 assert(len <= jvms()->loc_size(), "too many live locals");
703 for (int local = 0; local < len; local++) {
704 if (!live_locals.at(local)) {
705 set_local(local, top());
706 }
707 }
708 }
709
710 #ifdef ASSERT
711 //-------------------------dead_locals_are_killed------------------------------
712 // Return true if all dead locals are set to top in the map.
713 // Used to assert "clean" debug info at various points.
714 bool GraphKit::dead_locals_are_killed() {
715 if (method() == NULL || method()->code_size() == 0) {
716 // No locals need to be dead, so all is as it should be.
717 return true;
718 }
719
720 // Make sure somebody called kill_dead_locals upstream.
721 ResourceMark rm;
722 for (JVMState* jvms = this->jvms(); jvms != NULL; jvms = jvms->caller()) {
723 if (jvms->loc_size() == 0) continue; // no locals to consult
724 SafePointNode* map = jvms->map();
725 ciMethod* method = jvms->method();
726 int bci = jvms->bci();
727 if (jvms == this->jvms()) {
728 bci = this->bci(); // it might not yet be synched
729 }
730 MethodLivenessResult live_locals = method->liveness_at_bci(bci);
731 int len = (int)live_locals.size();
732 if (!live_locals.is_valid() || len == 0)
733 // This method is trivial, or is poisoned by a breakpoint.
734 return true;
735 assert(len == jvms->loc_size(), "live map consistent with locals map");
736 for (int local = 0; local < len; local++) {
737 if (!live_locals.at(local) && map->local(jvms, local) != top()) {
738 if (PrintMiscellaneous && (Verbose || WizardMode)) {
739 tty->print_cr("Zombie local %d: ", local);
740 jvms->dump();
741 }
742 return false;
743 }
744 }
745 }
746 return true;
747 }
748
749 #endif //ASSERT
750
751 // Helper function for enforcing certain bytecodes to reexecute if
752 // deoptimization happens
753 static bool should_reexecute_implied_by_bytecode(JVMState *jvms) {
754 ciMethod* cur_method = jvms->method();
755 int cur_bci = jvms->bci();
756 if (cur_method != NULL && cur_bci != InvocationEntryBci) {
757 Bytecodes::Code code = cur_method->java_code_at_bci(cur_bci);
758 return Interpreter::bytecode_should_reexecute(code);
759 } else
760 return false;
761 }
762
763 // Helper function for adding JVMState and debug information to node
764 void GraphKit::add_safepoint_edges(SafePointNode* call, bool must_throw) {
765 // Add the safepoint edges to the call (or other safepoint).
766
767 // Make sure dead locals are set to top. This
768 // should help register allocation time and cut down on the size
769 // of the deoptimization information.
770 assert(dead_locals_are_killed(), "garbage in debug info before safepoint");
771
772 // Walk the inline list to fill in the correct set of JVMState's
773 // Also fill in the associated edges for each JVMState.
774
775 JVMState* youngest_jvms = sync_jvms();
776
777 // Do we need debug info here? If it is a SafePoint and this method
778 // cannot de-opt, then we do NOT need any debug info.
779 bool full_info = (C->deopt_happens() || call->Opcode() != Op_SafePoint);
780
781 // If we are guaranteed to throw, we can prune everything but the
782 // input to the current bytecode.
783 bool can_prune_locals = false;
784 uint stack_slots_not_pruned = 0;
785 int inputs = 0, depth = 0;
786 if (must_throw) {
787 assert(method() == youngest_jvms->method(), "sanity");
788 if (compute_stack_effects(inputs, depth)) {
789 can_prune_locals = true;
790 stack_slots_not_pruned = inputs;
791 }
792 }
793
794 if (env()->jvmti_can_examine_or_deopt_anywhere()) {
795 // At any safepoint, this method can get breakpointed, which would
796 // then require an immediate deoptimization.
797 full_info = true;
798 can_prune_locals = false; // do not prune locals
799 stack_slots_not_pruned = 0;
800 }
801
802 // do not scribble on the input jvms
803 JVMState* out_jvms = youngest_jvms->clone_deep(C);
804 call->set_jvms(out_jvms); // Start jvms list for call node
805
806 // For a known set of bytecodes, the interpreter should reexecute them if
807 // deoptimization happens. We set the reexecute state for them here
808 if (out_jvms->is_reexecute_undefined() && //don't change if already specified
809 should_reexecute_implied_by_bytecode(out_jvms)) {
810 out_jvms->set_should_reexecute(true); //NOTE: youngest_jvms not changed
811 }
812
813 // Presize the call:
814 debug_only(uint non_debug_edges = call->req());
815 call->add_req_batch(top(), youngest_jvms->debug_depth());
816 assert(call->req() == non_debug_edges + youngest_jvms->debug_depth(), "");
817
818 // Set up edges so that the call looks like this:
819 // Call [state:] ctl io mem fptr retadr
820 // [parms:] parm0 ... parmN
821 // [root:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
822 // [...mid:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN [...]
823 // [young:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
824 // Note that caller debug info precedes callee debug info.
825
826 // Fill pointer walks backwards from "young:" to "root:" in the diagram above:
827 uint debug_ptr = call->req();
828
829 // Loop over the map input edges associated with jvms, add them
830 // to the call node, & reset all offsets to match call node array.
831 for (JVMState* in_jvms = youngest_jvms; in_jvms != NULL; ) {
832 uint debug_end = debug_ptr;
833 uint debug_start = debug_ptr - in_jvms->debug_size();
834 debug_ptr = debug_start; // back up the ptr
835
836 uint p = debug_start; // walks forward in [debug_start, debug_end)
837 uint j, k, l;
838 SafePointNode* in_map = in_jvms->map();
839 out_jvms->set_map(call);
840
841 if (can_prune_locals) {
842 assert(in_jvms->method() == out_jvms->method(), "sanity");
843 // If the current throw can reach an exception handler in this JVMS,
844 // then we must keep everything live that can reach that handler.
845 // As a quick and dirty approximation, we look for any handlers at all.
846 if (in_jvms->method()->has_exception_handlers()) {
847 can_prune_locals = false;
848 }
849 }
850
851 // Add the Locals
852 k = in_jvms->locoff();
853 l = in_jvms->loc_size();
854 out_jvms->set_locoff(p);
855 if (full_info && !can_prune_locals) {
856 for (j = 0; j < l; j++)
857 call->set_req(p++, in_map->in(k+j));
858 } else {
859 p += l; // already set to top above by add_req_batch
860 }
861
862 // Add the Expression Stack
863 k = in_jvms->stkoff();
864 l = in_jvms->sp();
865 out_jvms->set_stkoff(p);
866 if (full_info && !can_prune_locals) {
867 for (j = 0; j < l; j++)
868 call->set_req(p++, in_map->in(k+j));
869 } else if (can_prune_locals && stack_slots_not_pruned != 0) {
870 // Divide stack into {S0,...,S1}, where S0 is set to top.
871 uint s1 = stack_slots_not_pruned;
872 stack_slots_not_pruned = 0; // for next iteration
873 if (s1 > l) s1 = l;
874 uint s0 = l - s1;
875 p += s0; // skip the tops preinstalled by add_req_batch
876 for (j = s0; j < l; j++)
877 call->set_req(p++, in_map->in(k+j));
878 } else {
879 p += l; // already set to top above by add_req_batch
880 }
881
882 // Add the Monitors
883 k = in_jvms->monoff();
884 l = in_jvms->mon_size();
885 out_jvms->set_monoff(p);
886 for (j = 0; j < l; j++)
887 call->set_req(p++, in_map->in(k+j));
888
889 // Copy any scalar object fields.
890 k = in_jvms->scloff();
891 l = in_jvms->scl_size();
892 out_jvms->set_scloff(p);
893 for (j = 0; j < l; j++)
894 call->set_req(p++, in_map->in(k+j));
895
896 // Finish the new jvms.
897 out_jvms->set_endoff(p);
898
899 assert(out_jvms->endoff() == debug_end, "fill ptr must match");
900 assert(out_jvms->depth() == in_jvms->depth(), "depth must match");
901 assert(out_jvms->loc_size() == in_jvms->loc_size(), "size must match");
902 assert(out_jvms->mon_size() == in_jvms->mon_size(), "size must match");
903 assert(out_jvms->scl_size() == in_jvms->scl_size(), "size must match");
904 assert(out_jvms->debug_size() == in_jvms->debug_size(), "size must match");
905
906 // Update the two tail pointers in parallel.
907 out_jvms = out_jvms->caller();
908 in_jvms = in_jvms->caller();
909 }
910
911 assert(debug_ptr == non_debug_edges, "debug info must fit exactly");
912
913 // Test the correctness of JVMState::debug_xxx accessors:
914 assert(call->jvms()->debug_start() == non_debug_edges, "");
915 assert(call->jvms()->debug_end() == call->req(), "");
916 assert(call->jvms()->debug_depth() == call->req() - non_debug_edges, "");
917 }
918
919 bool GraphKit::compute_stack_effects(int& inputs, int& depth) {
920 Bytecodes::Code code = java_bc();
921 if (code == Bytecodes::_wide) {
922 code = method()->java_code_at_bci(bci() + 1);
923 }
924
925 BasicType rtype = T_ILLEGAL;
926 int rsize = 0;
927
928 if (code != Bytecodes::_illegal) {
929 depth = Bytecodes::depth(code); // checkcast=0, athrow=-1
930 rtype = Bytecodes::result_type(code); // checkcast=P, athrow=V
931 if (rtype < T_CONFLICT)
932 rsize = type2size[rtype];
933 }
934
935 switch (code) {
936 case Bytecodes::_illegal:
937 return false;
938
939 case Bytecodes::_ldc:
940 case Bytecodes::_ldc_w:
941 case Bytecodes::_ldc2_w:
942 inputs = 0;
943 break;
944
945 case Bytecodes::_dup: inputs = 1; break;
946 case Bytecodes::_dup_x1: inputs = 2; break;
947 case Bytecodes::_dup_x2: inputs = 3; break;
948 case Bytecodes::_dup2: inputs = 2; break;
949 case Bytecodes::_dup2_x1: inputs = 3; break;
950 case Bytecodes::_dup2_x2: inputs = 4; break;
951 case Bytecodes::_swap: inputs = 2; break;
952 case Bytecodes::_arraylength: inputs = 1; break;
953
954 case Bytecodes::_getstatic:
955 case Bytecodes::_putstatic:
956 case Bytecodes::_getfield:
957 case Bytecodes::_putfield:
958 {
959 bool is_get = (depth >= 0), is_static = (depth & 1);
960 bool ignore;
961 ciBytecodeStream iter(method());
962 iter.reset_to_bci(bci());
963 iter.next();
964 ciField* field = iter.get_field(ignore);
965 int size = field->type()->size();
966 inputs = (is_static ? 0 : 1);
967 if (is_get) {
968 depth = size - inputs;
969 } else {
970 inputs += size; // putxxx pops the value from the stack
971 depth = - inputs;
972 }
973 }
974 break;
975
976 case Bytecodes::_invokevirtual:
977 case Bytecodes::_invokespecial:
978 case Bytecodes::_invokestatic:
979 case Bytecodes::_invokedynamic:
980 case Bytecodes::_invokeinterface:
981 {
982 bool is_static = (depth == 0);
983 bool ignore;
984 ciBytecodeStream iter(method());
985 iter.reset_to_bci(bci());
986 iter.next();
987 ciMethod* method = iter.get_method(ignore);
988 inputs = method->arg_size_no_receiver();
989 if (!is_static) inputs += 1;
990 int size = method->return_type()->size();
991 depth = size - inputs;
992 }
993 break;
994
995 case Bytecodes::_multianewarray:
996 {
997 ciBytecodeStream iter(method());
998 iter.reset_to_bci(bci());
999 iter.next();
1000 inputs = iter.get_dimensions();
1001 assert(rsize == 1, "");
1002 depth = rsize - inputs;
1003 }
1004 break;
1005
1006 case Bytecodes::_ireturn:
1007 case Bytecodes::_lreturn:
1008 case Bytecodes::_freturn:
1009 case Bytecodes::_dreturn:
1010 case Bytecodes::_areturn:
1011 assert(rsize = -depth, "");
1012 inputs = rsize;
1013 break;
1014
1015 case Bytecodes::_jsr:
1016 case Bytecodes::_jsr_w:
1017 inputs = 0;
1018 depth = 1; // S.B. depth=1, not zero
1019 break;
1020
1021 default:
1022 // bytecode produces a typed result
1023 inputs = rsize - depth;
1024 assert(inputs >= 0, "");
1025 break;
1026 }
1027
1028 #ifdef ASSERT
1029 // spot check
1030 int outputs = depth + inputs;
1031 assert(outputs >= 0, "sanity");
1032 switch (code) {
1033 case Bytecodes::_checkcast: assert(inputs == 1 && outputs == 1, ""); break;
1034 case Bytecodes::_athrow: assert(inputs == 1 && outputs == 0, ""); break;
1035 case Bytecodes::_aload_0: assert(inputs == 0 && outputs == 1, ""); break;
1036 case Bytecodes::_return: assert(inputs == 0 && outputs == 0, ""); break;
1037 case Bytecodes::_drem: assert(inputs == 4 && outputs == 2, ""); break;
1038 }
1039 #endif //ASSERT
1040
1041 return true;
1042 }
1043
1044
1045
1046 //------------------------------basic_plus_adr---------------------------------
1047 Node* GraphKit::basic_plus_adr(Node* base, Node* ptr, Node* offset) {
1048 // short-circuit a common case
1049 if (offset == intcon(0)) return ptr;
1050 return _gvn.transform( new (C, 4) AddPNode(base, ptr, offset) );
1051 }
1052
1053 Node* GraphKit::ConvI2L(Node* offset) {
1054 // short-circuit a common case
1055 jint offset_con = find_int_con(offset, Type::OffsetBot);
1056 if (offset_con != Type::OffsetBot) {
1057 return longcon((long) offset_con);
1058 }
1059 return _gvn.transform( new (C, 2) ConvI2LNode(offset));
1060 }
1061 Node* GraphKit::ConvL2I(Node* offset) {
1062 // short-circuit a common case
1063 jlong offset_con = find_long_con(offset, (jlong)Type::OffsetBot);
1064 if (offset_con != (jlong)Type::OffsetBot) {
1065 return intcon((int) offset_con);
1066 }
1067 return _gvn.transform( new (C, 2) ConvL2INode(offset));
1068 }
1069
1070 //-------------------------load_object_klass-----------------------------------
1071 Node* GraphKit::load_object_klass(Node* obj) {
1072 // Special-case a fresh allocation to avoid building nodes:
1073 Node* akls = AllocateNode::Ideal_klass(obj, &_gvn);
1074 if (akls != NULL) return akls;
1075 Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes());
1076 return _gvn.transform( LoadKlassNode::make(_gvn, immutable_memory(), k_adr, TypeInstPtr::KLASS) );
1077 }
1078
1079 //-------------------------load_array_length-----------------------------------
1080 Node* GraphKit::load_array_length(Node* array) {
1081 // Special-case a fresh allocation to avoid building nodes:
1082 AllocateArrayNode* alloc = AllocateArrayNode::Ideal_array_allocation(array, &_gvn);
1083 Node *alen;
1084 if (alloc == NULL) {
1085 Node *r_adr = basic_plus_adr(array, arrayOopDesc::length_offset_in_bytes());
1086 alen = _gvn.transform( new (C, 3) LoadRangeNode(0, immutable_memory(), r_adr, TypeInt::POS));
1087 } else {
1088 alen = alloc->Ideal_length();
1089 Node* ccast = alloc->make_ideal_length(_gvn.type(array)->is_aryptr(), &_gvn);
1090 if (ccast != alen) {
1091 alen = _gvn.transform(ccast);
1092 }
1093 }
1094 return alen;
1095 }
1096
1097 //------------------------------do_null_check----------------------------------
1098 // Helper function to do a NULL pointer check. Returned value is
1099 // the incoming address with NULL casted away. You are allowed to use the
1100 // not-null value only if you are control dependent on the test.
1101 extern int explicit_null_checks_inserted,
1102 explicit_null_checks_elided;
1103 Node* GraphKit::null_check_common(Node* value, BasicType type,
1104 // optional arguments for variations:
1105 bool assert_null,
1106 Node* *null_control) {
1107 assert(!assert_null || null_control == NULL, "not both at once");
1108 if (stopped()) return top();
1109 if (!GenerateCompilerNullChecks && !assert_null && null_control == NULL) {
1110 // For some performance testing, we may wish to suppress null checking.
1111 value = cast_not_null(value); // Make it appear to be non-null (4962416).
1112 return value;
1113 }
1114 explicit_null_checks_inserted++;
1115
1116 // Construct NULL check
1117 Node *chk = NULL;
1118 switch(type) {
1119 case T_LONG : chk = new (C, 3) CmpLNode(value, _gvn.zerocon(T_LONG)); break;
1120 case T_INT : chk = new (C, 3) CmpINode( value, _gvn.intcon(0)); break;
1121 case T_ARRAY : // fall through
1122 type = T_OBJECT; // simplify further tests
1123 case T_OBJECT : {
1124 const Type *t = _gvn.type( value );
1125
1126 const TypeInstPtr* tp = t->isa_instptr();
1127 if (tp != NULL && !tp->klass()->is_loaded()
1128 // Only for do_null_check, not any of its siblings:
1129 && !assert_null && null_control == NULL) {
1130 // Usually, any field access or invocation on an unloaded oop type
1131 // will simply fail to link, since the statically linked class is
1132 // likely also to be unloaded. However, in -Xcomp mode, sometimes
1133 // the static class is loaded but the sharper oop type is not.
1134 // Rather than checking for this obscure case in lots of places,
1135 // we simply observe that a null check on an unloaded class
1136 // will always be followed by a nonsense operation, so we
1137 // can just issue the uncommon trap here.
1138 // Our access to the unloaded class will only be correct
1139 // after it has been loaded and initialized, which requires
1140 // a trip through the interpreter.
1141 #ifndef PRODUCT
1142 if (WizardMode) { tty->print("Null check of unloaded "); tp->klass()->print(); tty->cr(); }
1143 #endif
1144 uncommon_trap(Deoptimization::Reason_unloaded,
1145 Deoptimization::Action_reinterpret,
1146 tp->klass(), "!loaded");
1147 return top();
1148 }
1149
1150 if (assert_null) {
1151 // See if the type is contained in NULL_PTR.
1152 // If so, then the value is already null.
1153 if (t->higher_equal(TypePtr::NULL_PTR)) {
1154 explicit_null_checks_elided++;
1155 return value; // Elided null assert quickly!
1156 }
1157 } else {
1158 // See if mixing in the NULL pointer changes type.
1159 // If so, then the NULL pointer was not allowed in the original
1160 // type. In other words, "value" was not-null.
1161 if (t->meet(TypePtr::NULL_PTR) != t) {
1162 // same as: if (!TypePtr::NULL_PTR->higher_equal(t)) ...
1163 explicit_null_checks_elided++;
1164 return value; // Elided null check quickly!
1165 }
1166 }
1167 chk = new (C, 3) CmpPNode( value, null() );
1168 break;
1169 }
1170
1171 default : ShouldNotReachHere();
1172 }
1173 assert(chk != NULL, "sanity check");
1174 chk = _gvn.transform(chk);
1175
1176 BoolTest::mask btest = assert_null ? BoolTest::eq : BoolTest::ne;
1177 BoolNode *btst = new (C, 2) BoolNode( chk, btest);
1178 Node *tst = _gvn.transform( btst );
1179
1180 //-----------
1181 // if peephole optimizations occurred, a prior test existed.
1182 // If a prior test existed, maybe it dominates as we can avoid this test.
1183 if (tst != btst && type == T_OBJECT) {
1184 // At this point we want to scan up the CFG to see if we can
1185 // find an identical test (and so avoid this test altogether).
1186 Node *cfg = control();
1187 int depth = 0;
1188 while( depth < 16 ) { // Limit search depth for speed
1189 if( cfg->Opcode() == Op_IfTrue &&
1190 cfg->in(0)->in(1) == tst ) {
1191 // Found prior test. Use "cast_not_null" to construct an identical
1192 // CastPP (and hence hash to) as already exists for the prior test.
1193 // Return that casted value.
1194 if (assert_null) {
1195 replace_in_map(value, null());
1196 return null(); // do not issue the redundant test
1197 }
1198 Node *oldcontrol = control();
1199 set_control(cfg);
1200 Node *res = cast_not_null(value);
1201 set_control(oldcontrol);
1202 explicit_null_checks_elided++;
1203 return res;
1204 }
1205 cfg = IfNode::up_one_dom(cfg, /*linear_only=*/ true);
1206 if (cfg == NULL) break; // Quit at region nodes
1207 depth++;
1208 }
1209 }
1210
1211 //-----------
1212 // Branch to failure if null
1213 float ok_prob = PROB_MAX; // a priori estimate: nulls never happen
1214 Deoptimization::DeoptReason reason;
1215 if (assert_null)
1216 reason = Deoptimization::Reason_null_assert;
1217 else if (type == T_OBJECT)
1218 reason = Deoptimization::Reason_null_check;
1219 else
1220 reason = Deoptimization::Reason_div0_check;
1221
1222 // %%% Since Reason_unhandled is not recorded on a per-bytecode basis,
1223 // ciMethodData::has_trap_at will return a conservative -1 if any
1224 // must-be-null assertion has failed. This could cause performance
1225 // problems for a method after its first do_null_assert failure.
1226 // Consider using 'Reason_class_check' instead?
1227
1228 // To cause an implicit null check, we set the not-null probability
1229 // to the maximum (PROB_MAX). For an explicit check the probability
1230 // is set to a smaller value.
1231 if (null_control != NULL || too_many_traps(reason)) {
1232 // probability is less likely
1233 ok_prob = PROB_LIKELY_MAG(3);
1234 } else if (!assert_null &&
1235 (ImplicitNullCheckThreshold > 0) &&
1236 method() != NULL &&
1237 (method()->method_data()->trap_count(reason)
1238 >= (uint)ImplicitNullCheckThreshold)) {
1239 ok_prob = PROB_LIKELY_MAG(3);
1240 }
1241
1242 if (null_control != NULL) {
1243 IfNode* iff = create_and_map_if(control(), tst, ok_prob, COUNT_UNKNOWN);
1244 Node* null_true = _gvn.transform( new (C, 1) IfFalseNode(iff));
1245 set_control( _gvn.transform( new (C, 1) IfTrueNode(iff)));
1246 if (null_true == top())
1247 explicit_null_checks_elided++;
1248 (*null_control) = null_true;
1249 } else {
1250 BuildCutout unless(this, tst, ok_prob);
1251 // Check for optimizer eliding test at parse time
1252 if (stopped()) {
1253 // Failure not possible; do not bother making uncommon trap.
1254 explicit_null_checks_elided++;
1255 } else if (assert_null) {
1256 uncommon_trap(reason,
1257 Deoptimization::Action_make_not_entrant,
1258 NULL, "assert_null");
1259 } else {
1260 replace_in_map(value, zerocon(type));
1261 builtin_throw(reason);
1262 }
1263 }
1264
1265 // Must throw exception, fall-thru not possible?
1266 if (stopped()) {
1267 return top(); // No result
1268 }
1269
1270 if (assert_null) {
1271 // Cast obj to null on this path.
1272 replace_in_map(value, zerocon(type));
1273 return zerocon(type);
1274 }
1275
1276 // Cast obj to not-null on this path, if there is no null_control.
1277 // (If there is a null_control, a non-null value may come back to haunt us.)
1278 if (type == T_OBJECT) {
1279 Node* cast = cast_not_null(value, false);
1280 if (null_control == NULL || (*null_control) == top())
1281 replace_in_map(value, cast);
1282 value = cast;
1283 }
1284
1285 return value;
1286 }
1287
1288
1289 //------------------------------cast_not_null----------------------------------
1290 // Cast obj to not-null on this path
1291 Node* GraphKit::cast_not_null(Node* obj, bool do_replace_in_map) {
1292 const Type *t = _gvn.type(obj);
1293 const Type *t_not_null = t->join(TypePtr::NOTNULL);
1294 // Object is already not-null?
1295 if( t == t_not_null ) return obj;
1296
1297 Node *cast = new (C, 2) CastPPNode(obj,t_not_null);
1298 cast->init_req(0, control());
1299 cast = _gvn.transform( cast );
1300
1301 // Scan for instances of 'obj' in the current JVM mapping.
1302 // These instances are known to be not-null after the test.
1303 if (do_replace_in_map)
1304 replace_in_map(obj, cast);
1305
1306 return cast; // Return casted value
1307 }
1308
1309
1310 //--------------------------replace_in_map-------------------------------------
1311 void GraphKit::replace_in_map(Node* old, Node* neww) {
1312 this->map()->replace_edge(old, neww);
1313
1314 // Note: This operation potentially replaces any edge
1315 // on the map. This includes locals, stack, and monitors
1316 // of the current (innermost) JVM state.
1317
1318 // We can consider replacing in caller maps.
1319 // The idea would be that an inlined function's null checks
1320 // can be shared with the entire inlining tree.
1321 // The expense of doing this is that the PreserveJVMState class
1322 // would have to preserve caller states too, with a deep copy.
1323 }
1324
1325
1326
1327 //=============================================================================
1328 //--------------------------------memory---------------------------------------
1329 Node* GraphKit::memory(uint alias_idx) {
1330 MergeMemNode* mem = merged_memory();
1331 Node* p = mem->memory_at(alias_idx);
1332 _gvn.set_type(p, Type::MEMORY); // must be mapped
1333 return p;
1334 }
1335
1336 //-----------------------------reset_memory------------------------------------
1337 Node* GraphKit::reset_memory() {
1338 Node* mem = map()->memory();
1339 // do not use this node for any more parsing!
1340 debug_only( map()->set_memory((Node*)NULL) );
1341 return _gvn.transform( mem );
1342 }
1343
1344 //------------------------------set_all_memory---------------------------------
1345 void GraphKit::set_all_memory(Node* newmem) {
1346 Node* mergemem = MergeMemNode::make(C, newmem);
1347 gvn().set_type_bottom(mergemem);
1348 map()->set_memory(mergemem);
1349 }
1350
1351 //------------------------------set_all_memory_call----------------------------
1352 void GraphKit::set_all_memory_call(Node* call) {
1353 Node* newmem = _gvn.transform( new (C, 1) ProjNode(call, TypeFunc::Memory) );
1354 set_all_memory(newmem);
1355 }
1356
1357 //=============================================================================
1358 //
1359 // parser factory methods for MemNodes
1360 //
1361 // These are layered on top of the factory methods in LoadNode and StoreNode,
1362 // and integrate with the parser's memory state and _gvn engine.
1363 //
1364
1365 // factory methods in "int adr_idx"
1366 Node* GraphKit::make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
1367 int adr_idx,
1368 bool require_atomic_access) {
1369 assert(adr_idx != Compile::AliasIdxTop, "use other make_load factory" );
1370 const TypePtr* adr_type = NULL; // debug-mode-only argument
1371 debug_only(adr_type = C->get_adr_type(adr_idx));
1372 Node* mem = memory(adr_idx);
1373 Node* ld;
1374 if (require_atomic_access && bt == T_LONG) {
1375 ld = LoadLNode::make_atomic(C, ctl, mem, adr, adr_type, t);
1376 } else {
1377 ld = LoadNode::make(_gvn, ctl, mem, adr, adr_type, t, bt);
1378 }
1379 return _gvn.transform(ld);
1380 }
1381
1382 Node* GraphKit::store_to_memory(Node* ctl, Node* adr, Node *val, BasicType bt,
1383 int adr_idx,
1384 bool require_atomic_access) {
1385 assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1386 const TypePtr* adr_type = NULL;
1387 debug_only(adr_type = C->get_adr_type(adr_idx));
1388 Node *mem = memory(adr_idx);
1389 Node* st;
1390 if (require_atomic_access && bt == T_LONG) {
1391 st = StoreLNode::make_atomic(C, ctl, mem, adr, adr_type, val);
1392 } else {
1393 st = StoreNode::make(_gvn, ctl, mem, adr, adr_type, val, bt);
1394 }
1395 st = _gvn.transform(st);
1396 set_memory(st, adr_idx);
1397 // Back-to-back stores can only remove intermediate store with DU info
1398 // so push on worklist for optimizer.
1399 if (mem->req() > MemNode::Address && adr == mem->in(MemNode::Address))
1400 record_for_igvn(st);
1401
1402 return st;
1403 }
1404
1405
1406 void GraphKit::pre_barrier(Node* ctl,
1407 Node* obj,
1408 Node* adr,
1409 uint adr_idx,
1410 Node* val,
1411 const TypeOopPtr* val_type,
1412 BasicType bt) {
1413 BarrierSet* bs = Universe::heap()->barrier_set();
1414 set_control(ctl);
1415 switch (bs->kind()) {
1416 case BarrierSet::G1SATBCT:
1417 case BarrierSet::G1SATBCTLogging:
1418 g1_write_barrier_pre(obj, adr, adr_idx, val, val_type, bt);
1419 break;
1420
1421 case BarrierSet::CardTableModRef:
1422 case BarrierSet::CardTableExtension:
1423 case BarrierSet::ModRef:
1424 break;
1425
1426 case BarrierSet::Other:
1427 default :
1428 ShouldNotReachHere();
1429
1430 }
1431 }
1432
1433 void GraphKit::post_barrier(Node* ctl,
1434 Node* store,
1435 Node* obj,
1436 Node* adr,
1437 uint adr_idx,
1438 Node* val,
1439 BasicType bt,
1440 bool use_precise) {
1441 BarrierSet* bs = Universe::heap()->barrier_set();
1442 set_control(ctl);
1443 switch (bs->kind()) {
1444 case BarrierSet::G1SATBCT:
1445 case BarrierSet::G1SATBCTLogging:
1446 g1_write_barrier_post(store, obj, adr, adr_idx, val, bt, use_precise);
1447 break;
1448
1449 case BarrierSet::CardTableModRef:
1450 case BarrierSet::CardTableExtension:
1451 write_barrier_post(store, obj, adr, val, use_precise);
1452 break;
1453
1454 case BarrierSet::ModRef:
1455 break;
1456
1457 case BarrierSet::Other:
1458 default :
1459 ShouldNotReachHere();
1460
1461 }
1462 }
1463
1464 Node* GraphKit::store_oop(Node* ctl,
1465 Node* obj,
1466 Node* adr,
1467 const TypePtr* adr_type,
1468 Node* val,
1469 const TypeOopPtr* val_type,
1470 BasicType bt,
1471 bool use_precise) {
1472
1473 set_control(ctl);
1474 if (stopped()) return top(); // Dead path ?
1475
1476 assert(bt == T_OBJECT, "sanity");
1477 assert(val != NULL, "not dead path");
1478 uint adr_idx = C->get_alias_index(adr_type);
1479 assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1480
1481 pre_barrier(control(), obj, adr, adr_idx, val, val_type, bt);
1482 Node* store = store_to_memory(control(), adr, val, bt, adr_idx);
1483 post_barrier(control(), store, obj, adr, adr_idx, val, bt, use_precise);
1484 return store;
1485 }
1486
1487 // Could be an array or object we don't know at compile time (unsafe ref.)
1488 Node* GraphKit::store_oop_to_unknown(Node* ctl,
1489 Node* obj, // containing obj
1490 Node* adr, // actual adress to store val at
1491 const TypePtr* adr_type,
1492 Node* val,
1493 BasicType bt) {
1494 Compile::AliasType* at = C->alias_type(adr_type);
1495 const TypeOopPtr* val_type = NULL;
1496 if (adr_type->isa_instptr()) {
1497 if (at->field() != NULL) {
1498 // known field. This code is a copy of the do_put_xxx logic.
1499 ciField* field = at->field();
1500 if (!field->type()->is_loaded()) {
1501 val_type = TypeInstPtr::BOTTOM;
1502 } else {
1503 val_type = TypeOopPtr::make_from_klass(field->type()->as_klass());
1504 }
1505 }
1506 } else if (adr_type->isa_aryptr()) {
1507 val_type = adr_type->is_aryptr()->elem()->make_oopptr();
1508 }
1509 if (val_type == NULL) {
1510 val_type = TypeInstPtr::BOTTOM;
1511 }
1512 return store_oop(ctl, obj, adr, adr_type, val, val_type, bt, true);
1513 }
1514
1515
1516 //-------------------------array_element_address-------------------------
1517 Node* GraphKit::array_element_address(Node* ary, Node* idx, BasicType elembt,
1518 const TypeInt* sizetype) {
1519 uint shift = exact_log2(type2aelembytes(elembt));
1520 uint header = arrayOopDesc::base_offset_in_bytes(elembt);
1521
1522 // short-circuit a common case (saves lots of confusing waste motion)
1523 jint idx_con = find_int_con(idx, -1);
1524 if (idx_con >= 0) {
1525 intptr_t offset = header + ((intptr_t)idx_con << shift);
1526 return basic_plus_adr(ary, offset);
1527 }
1528
1529 // must be correct type for alignment purposes
1530 Node* base = basic_plus_adr(ary, header);
1531 #ifdef _LP64
1532 // The scaled index operand to AddP must be a clean 64-bit value.
1533 // Java allows a 32-bit int to be incremented to a negative
1534 // value, which appears in a 64-bit register as a large
1535 // positive number. Using that large positive number as an
1536 // operand in pointer arithmetic has bad consequences.
1537 // On the other hand, 32-bit overflow is rare, and the possibility
1538 // can often be excluded, if we annotate the ConvI2L node with
1539 // a type assertion that its value is known to be a small positive
1540 // number. (The prior range check has ensured this.)
1541 // This assertion is used by ConvI2LNode::Ideal.
1542 int index_max = max_jint - 1; // array size is max_jint, index is one less
1543 if (sizetype != NULL) index_max = sizetype->_hi - 1;
1544 const TypeLong* lidxtype = TypeLong::make(CONST64(0), index_max, Type::WidenMax);
1545 idx = _gvn.transform( new (C, 2) ConvI2LNode(idx, lidxtype) );
1546 #endif
1547 Node* scale = _gvn.transform( new (C, 3) LShiftXNode(idx, intcon(shift)) );
1548 return basic_plus_adr(ary, base, scale);
1549 }
1550
1551 //-------------------------load_array_element-------------------------
1552 Node* GraphKit::load_array_element(Node* ctl, Node* ary, Node* idx, const TypeAryPtr* arytype) {
1553 const Type* elemtype = arytype->elem();
1554 BasicType elembt = elemtype->array_element_basic_type();
1555 Node* adr = array_element_address(ary, idx, elembt, arytype->size());
1556 Node* ld = make_load(ctl, adr, elemtype, elembt, arytype);
1557 return ld;
1558 }
1559
1560 //-------------------------set_arguments_for_java_call-------------------------
1561 // Arguments (pre-popped from the stack) are taken from the JVMS.
1562 void GraphKit::set_arguments_for_java_call(CallJavaNode* call) {
1563 // Add the call arguments:
1564 uint nargs = call->method()->arg_size();
1565 for (uint i = 0; i < nargs; i++) {
1566 Node* arg = argument(i);
1567 call->init_req(i + TypeFunc::Parms, arg);
1568 }
1569 }
1570
1571 //---------------------------set_edges_for_java_call---------------------------
1572 // Connect a newly created call into the current JVMS.
1573 // A return value node (if any) is returned from set_edges_for_java_call.
1574 void GraphKit::set_edges_for_java_call(CallJavaNode* call, bool must_throw) {
1575
1576 // Add the predefined inputs:
1577 call->init_req( TypeFunc::Control, control() );
1578 call->init_req( TypeFunc::I_O , i_o() );
1579 call->init_req( TypeFunc::Memory , reset_memory() );
1580 call->init_req( TypeFunc::FramePtr, frameptr() );
1581 call->init_req( TypeFunc::ReturnAdr, top() );
1582
1583 add_safepoint_edges(call, must_throw);
1584
1585 Node* xcall = _gvn.transform(call);
1586
1587 if (xcall == top()) {
1588 set_control(top());
1589 return;
1590 }
1591 assert(xcall == call, "call identity is stable");
1592
1593 // Re-use the current map to produce the result.
1594
1595 set_control(_gvn.transform(new (C, 1) ProjNode(call, TypeFunc::Control)));
1596 set_i_o( _gvn.transform(new (C, 1) ProjNode(call, TypeFunc::I_O )));
1597 set_all_memory_call(xcall);
1598
1599 //return xcall; // no need, caller already has it
1600 }
1601
1602 Node* GraphKit::set_results_for_java_call(CallJavaNode* call) {
1603 if (stopped()) return top(); // maybe the call folded up?
1604
1605 // Capture the return value, if any.
1606 Node* ret;
1607 if (call->method() == NULL ||
1608 call->method()->return_type()->basic_type() == T_VOID)
1609 ret = top();
1610 else ret = _gvn.transform(new (C, 1) ProjNode(call, TypeFunc::Parms));
1611
1612 // Note: Since any out-of-line call can produce an exception,
1613 // we always insert an I_O projection from the call into the result.
1614
1615 make_slow_call_ex(call, env()->Throwable_klass(), false);
1616
1617 return ret;
1618 }
1619
1620 //--------------------set_predefined_input_for_runtime_call--------------------
1621 // Reading and setting the memory state is way conservative here.
1622 // The real problem is that I am not doing real Type analysis on memory,
1623 // so I cannot distinguish card mark stores from other stores. Across a GC
1624 // point the Store Barrier and the card mark memory has to agree. I cannot
1625 // have a card mark store and its barrier split across the GC point from
1626 // either above or below. Here I get that to happen by reading ALL of memory.
1627 // A better answer would be to separate out card marks from other memory.
1628 // For now, return the input memory state, so that it can be reused
1629 // after the call, if this call has restricted memory effects.
1630 Node* GraphKit::set_predefined_input_for_runtime_call(SafePointNode* call) {
1631 // Set fixed predefined input arguments
1632 Node* memory = reset_memory();
1633 call->init_req( TypeFunc::Control, control() );
1634 call->init_req( TypeFunc::I_O, top() ); // does no i/o
1635 call->init_req( TypeFunc::Memory, memory ); // may gc ptrs
1636 call->init_req( TypeFunc::FramePtr, frameptr() );
1637 call->init_req( TypeFunc::ReturnAdr, top() );
1638 return memory;
1639 }
1640
1641 //-------------------set_predefined_output_for_runtime_call--------------------
1642 // Set control and memory (not i_o) from the call.
1643 // If keep_mem is not NULL, use it for the output state,
1644 // except for the RawPtr output of the call, if hook_mem is TypeRawPtr::BOTTOM.
1645 // If hook_mem is NULL, this call produces no memory effects at all.
1646 // If hook_mem is a Java-visible memory slice (such as arraycopy operands),
1647 // then only that memory slice is taken from the call.
1648 // In the last case, we must put an appropriate memory barrier before
1649 // the call, so as to create the correct anti-dependencies on loads
1650 // preceding the call.
1651 void GraphKit::set_predefined_output_for_runtime_call(Node* call,
1652 Node* keep_mem,
1653 const TypePtr* hook_mem) {
1654 // no i/o
1655 set_control(_gvn.transform( new (C, 1) ProjNode(call,TypeFunc::Control) ));
1656 if (keep_mem) {
1657 // First clone the existing memory state
1658 set_all_memory(keep_mem);
1659 if (hook_mem != NULL) {
1660 // Make memory for the call
1661 Node* mem = _gvn.transform( new (C, 1) ProjNode(call, TypeFunc::Memory) );
1662 // Set the RawPtr memory state only. This covers all the heap top/GC stuff
1663 // We also use hook_mem to extract specific effects from arraycopy stubs.
1664 set_memory(mem, hook_mem);
1665 }
1666 // ...else the call has NO memory effects.
1667
1668 // Make sure the call advertises its memory effects precisely.
1669 // This lets us build accurate anti-dependences in gcm.cpp.
1670 assert(C->alias_type(call->adr_type()) == C->alias_type(hook_mem),
1671 "call node must be constructed correctly");
1672 } else {
1673 assert(hook_mem == NULL, "");
1674 // This is not a "slow path" call; all memory comes from the call.
1675 set_all_memory_call(call);
1676 }
1677 }
1678
1679 //------------------------------increment_counter------------------------------
1680 // for statistics: increment a VM counter by 1
1681
1682 void GraphKit::increment_counter(address counter_addr) {
1683 Node* adr1 = makecon(TypeRawPtr::make(counter_addr));
1684 increment_counter(adr1);
1685 }
1686
1687 void GraphKit::increment_counter(Node* counter_addr) {
1688 int adr_type = Compile::AliasIdxRaw;
1689 Node* cnt = make_load(NULL, counter_addr, TypeInt::INT, T_INT, adr_type);
1690 Node* incr = _gvn.transform(new (C, 3) AddINode(cnt, _gvn.intcon(1)));
1691 store_to_memory( NULL, counter_addr, incr, T_INT, adr_type );
1692 }
1693
1694
1695 //------------------------------uncommon_trap----------------------------------
1696 // Bail out to the interpreter in mid-method. Implemented by calling the
1697 // uncommon_trap blob. This helper function inserts a runtime call with the
1698 // right debug info.
1699 void GraphKit::uncommon_trap(int trap_request,
1700 ciKlass* klass, const char* comment,
1701 bool must_throw,
1702 bool keep_exact_action) {
1703 if (failing()) stop();
1704 if (stopped()) return; // trap reachable?
1705
1706 // Note: If ProfileTraps is true, and if a deopt. actually
1707 // occurs here, the runtime will make sure an MDO exists. There is
1708 // no need to call method()->build_method_data() at this point.
1709
1710 #ifdef ASSERT
1711 if (!must_throw) {
1712 // Make sure the stack has at least enough depth to execute
1713 // the current bytecode.
1714 int inputs, ignore;
1715 if (compute_stack_effects(inputs, ignore)) {
1716 assert(sp() >= inputs, "must have enough JVMS stack to execute");
1717 // It is a frequent error in library_call.cpp to issue an
1718 // uncommon trap with the _sp value already popped.
1719 }
1720 }
1721 #endif
1722
1723 Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
1724 Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
1725
1726 switch (action) {
1727 case Deoptimization::Action_maybe_recompile:
1728 case Deoptimization::Action_reinterpret:
1729 // Temporary fix for 6529811 to allow virtual calls to be sure they
1730 // get the chance to go from mono->bi->mega
1731 if (!keep_exact_action &&
1732 Deoptimization::trap_request_index(trap_request) < 0 &&
1733 too_many_recompiles(reason)) {
1734 // This BCI is causing too many recompilations.
1735 action = Deoptimization::Action_none;
1736 trap_request = Deoptimization::make_trap_request(reason, action);
1737 } else {
1738 C->set_trap_can_recompile(true);
1739 }
1740 break;
1741 case Deoptimization::Action_make_not_entrant:
1742 C->set_trap_can_recompile(true);
1743 break;
1744 #ifdef ASSERT
1745 case Deoptimization::Action_none:
1746 case Deoptimization::Action_make_not_compilable:
1747 break;
1748 default:
1749 assert(false, "bad action");
1750 #endif
1751 }
1752
1753 if (TraceOptoParse) {
1754 char buf[100];
1755 tty->print_cr("Uncommon trap %s at bci:%d",
1756 Deoptimization::format_trap_request(buf, sizeof(buf),
1757 trap_request), bci());
1758 }
1759
1760 CompileLog* log = C->log();
1761 if (log != NULL) {
1762 int kid = (klass == NULL)? -1: log->identify(klass);
1763 log->begin_elem("uncommon_trap bci='%d'", bci());
1764 char buf[100];
1765 log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf),
1766 trap_request));
1767 if (kid >= 0) log->print(" klass='%d'", kid);
1768 if (comment != NULL) log->print(" comment='%s'", comment);
1769 log->end_elem();
1770 }
1771
1772 // Make sure any guarding test views this path as very unlikely
1773 Node *i0 = control()->in(0);
1774 if (i0 != NULL && i0->is_If()) { // Found a guarding if test?
1775 IfNode *iff = i0->as_If();
1776 float f = iff->_prob; // Get prob
1777 if (control()->Opcode() == Op_IfTrue) {
1778 if (f > PROB_UNLIKELY_MAG(4))
1779 iff->_prob = PROB_MIN;
1780 } else {
1781 if (f < PROB_LIKELY_MAG(4))
1782 iff->_prob = PROB_MAX;
1783 }
1784 }
1785
1786 // Clear out dead values from the debug info.
1787 kill_dead_locals();
1788
1789 // Now insert the uncommon trap subroutine call
1790 address call_addr = SharedRuntime::uncommon_trap_blob()->instructions_begin();
1791 const TypePtr* no_memory_effects = NULL;
1792 // Pass the index of the class to be loaded
1793 Node* call = make_runtime_call(RC_NO_LEAF | RC_UNCOMMON |
1794 (must_throw ? RC_MUST_THROW : 0),
1795 OptoRuntime::uncommon_trap_Type(),
1796 call_addr, "uncommon_trap", no_memory_effects,
1797 intcon(trap_request));
1798 assert(call->as_CallStaticJava()->uncommon_trap_request() == trap_request,
1799 "must extract request correctly from the graph");
1800 assert(trap_request != 0, "zero value reserved by uncommon_trap_request");
1801
1802 call->set_req(TypeFunc::ReturnAdr, returnadr());
1803 // The debug info is the only real input to this call.
1804
1805 // Halt-and-catch fire here. The above call should never return!
1806 HaltNode* halt = new(C, TypeFunc::Parms) HaltNode(control(), frameptr());
1807 _gvn.set_type_bottom(halt);
1808 root()->add_req(halt);
1809
1810 stop_and_kill_map();
1811 }
1812
1813
1814 //--------------------------just_allocated_object------------------------------
1815 // Report the object that was just allocated.
1816 // It must be the case that there are no intervening safepoints.
1817 // We use this to determine if an object is so "fresh" that
1818 // it does not require card marks.
1819 Node* GraphKit::just_allocated_object(Node* current_control) {
1820 if (C->recent_alloc_ctl() == current_control)
1821 return C->recent_alloc_obj();
1822 return NULL;
1823 }
1824
1825
1826 void GraphKit::round_double_arguments(ciMethod* dest_method) {
1827 // (Note: TypeFunc::make has a cache that makes this fast.)
1828 const TypeFunc* tf = TypeFunc::make(dest_method);
1829 int nargs = tf->_domain->_cnt - TypeFunc::Parms;
1830 for (int j = 0; j < nargs; j++) {
1831 const Type *targ = tf->_domain->field_at(j + TypeFunc::Parms);
1832 if( targ->basic_type() == T_DOUBLE ) {
1833 // If any parameters are doubles, they must be rounded before
1834 // the call, dstore_rounding does gvn.transform
1835 Node *arg = argument(j);
1836 arg = dstore_rounding(arg);
1837 set_argument(j, arg);
1838 }
1839 }
1840 }
1841
1842 void GraphKit::round_double_result(ciMethod* dest_method) {
1843 // A non-strict method may return a double value which has an extended
1844 // exponent, but this must not be visible in a caller which is 'strict'
1845 // If a strict caller invokes a non-strict callee, round a double result
1846
1847 BasicType result_type = dest_method->return_type()->basic_type();
1848 assert( method() != NULL, "must have caller context");
1849 if( result_type == T_DOUBLE && method()->is_strict() && !dest_method->is_strict() ) {
1850 // Destination method's return value is on top of stack
1851 // dstore_rounding() does gvn.transform
1852 Node *result = pop_pair();
1853 result = dstore_rounding(result);
1854 push_pair(result);
1855 }
1856 }
1857
1858 // rounding for strict float precision conformance
1859 Node* GraphKit::precision_rounding(Node* n) {
1860 return UseStrictFP && _method->flags().is_strict()
1861 && UseSSE == 0 && Matcher::strict_fp_requires_explicit_rounding
1862 ? _gvn.transform( new (C, 2) RoundFloatNode(0, n) )
1863 : n;
1864 }
1865
1866 // rounding for strict double precision conformance
1867 Node* GraphKit::dprecision_rounding(Node *n) {
1868 return UseStrictFP && _method->flags().is_strict()
1869 && UseSSE <= 1 && Matcher::strict_fp_requires_explicit_rounding
1870 ? _gvn.transform( new (C, 2) RoundDoubleNode(0, n) )
1871 : n;
1872 }
1873
1874 // rounding for non-strict double stores
1875 Node* GraphKit::dstore_rounding(Node* n) {
1876 return Matcher::strict_fp_requires_explicit_rounding
1877 && UseSSE <= 1
1878 ? _gvn.transform( new (C, 2) RoundDoubleNode(0, n) )
1879 : n;
1880 }
1881
1882 //=============================================================================
1883 // Generate a fast path/slow path idiom. Graph looks like:
1884 // [foo] indicates that 'foo' is a parameter
1885 //
1886 // [in] NULL
1887 // \ /
1888 // CmpP
1889 // Bool ne
1890 // If
1891 // / \
1892 // True False-<2>
1893 // / |
1894 // / cast_not_null
1895 // Load | | ^
1896 // [fast_test] | |
1897 // gvn to opt_test | |
1898 // / \ | <1>
1899 // True False |
1900 // | \\ |
1901 // [slow_call] \[fast_result]
1902 // Ctl Val \ \
1903 // | \ \
1904 // Catch <1> \ \
1905 // / \ ^ \ \
1906 // Ex No_Ex | \ \
1907 // | \ \ | \ <2> \
1908 // ... \ [slow_res] | | \ [null_result]
1909 // \ \--+--+--- | |
1910 // \ | / \ | /
1911 // --------Region Phi
1912 //
1913 //=============================================================================
1914 // Code is structured as a series of driver functions all called 'do_XXX' that
1915 // call a set of helper functions. Helper functions first, then drivers.
1916
1917 //------------------------------null_check_oop---------------------------------
1918 // Null check oop. Set null-path control into Region in slot 3.
1919 // Make a cast-not-nullness use the other not-null control. Return cast.
1920 Node* GraphKit::null_check_oop(Node* value, Node* *null_control,
1921 bool never_see_null) {
1922 // Initial NULL check taken path
1923 (*null_control) = top();
1924 Node* cast = null_check_common(value, T_OBJECT, false, null_control);
1925
1926 // Generate uncommon_trap:
1927 if (never_see_null && (*null_control) != top()) {
1928 // If we see an unexpected null at a check-cast we record it and force a
1929 // recompile; the offending check-cast will be compiled to handle NULLs.
1930 // If we see more than one offending BCI, then all checkcasts in the
1931 // method will be compiled to handle NULLs.
1932 PreserveJVMState pjvms(this);
1933 set_control(*null_control);
1934 replace_in_map(value, null());
1935 uncommon_trap(Deoptimization::Reason_null_check,
1936 Deoptimization::Action_make_not_entrant);
1937 (*null_control) = top(); // NULL path is dead
1938 }
1939
1940 // Cast away null-ness on the result
1941 return cast;
1942 }
1943
1944 //------------------------------opt_iff----------------------------------------
1945 // Optimize the fast-check IfNode. Set the fast-path region slot 2.
1946 // Return slow-path control.
1947 Node* GraphKit::opt_iff(Node* region, Node* iff) {
1948 IfNode *opt_iff = _gvn.transform(iff)->as_If();
1949
1950 // Fast path taken; set region slot 2
1951 Node *fast_taken = _gvn.transform( new (C, 1) IfFalseNode(opt_iff) );
1952 region->init_req(2,fast_taken); // Capture fast-control
1953
1954 // Fast path not-taken, i.e. slow path
1955 Node *slow_taken = _gvn.transform( new (C, 1) IfTrueNode(opt_iff) );
1956 return slow_taken;
1957 }
1958
1959 //-----------------------------make_runtime_call-------------------------------
1960 Node* GraphKit::make_runtime_call(int flags,
1961 const TypeFunc* call_type, address call_addr,
1962 const char* call_name,
1963 const TypePtr* adr_type,
1964 // The following parms are all optional.
1965 // The first NULL ends the list.
1966 Node* parm0, Node* parm1,
1967 Node* parm2, Node* parm3,
1968 Node* parm4, Node* parm5,
1969 Node* parm6, Node* parm7) {
1970 // Slow-path call
1971 int size = call_type->domain()->cnt();
1972 bool is_leaf = !(flags & RC_NO_LEAF);
1973 bool has_io = (!is_leaf && !(flags & RC_NO_IO));
1974 if (call_name == NULL) {
1975 assert(!is_leaf, "must supply name for leaf");
1976 call_name = OptoRuntime::stub_name(call_addr);
1977 }
1978 CallNode* call;
1979 if (!is_leaf) {
1980 call = new(C, size) CallStaticJavaNode(call_type, call_addr, call_name,
1981 bci(), adr_type);
1982 } else if (flags & RC_NO_FP) {
1983 call = new(C, size) CallLeafNoFPNode(call_type, call_addr, call_name, adr_type);
1984 } else {
1985 call = new(C, size) CallLeafNode(call_type, call_addr, call_name, adr_type);
1986 }
1987
1988 // The following is similar to set_edges_for_java_call,
1989 // except that the memory effects of the call are restricted to AliasIdxRaw.
1990
1991 // Slow path call has no side-effects, uses few values
1992 bool wide_in = !(flags & RC_NARROW_MEM);
1993 bool wide_out = (C->get_alias_index(adr_type) == Compile::AliasIdxBot);
1994
1995 Node* prev_mem = NULL;
1996 if (wide_in) {
1997 prev_mem = set_predefined_input_for_runtime_call(call);
1998 } else {
1999 assert(!wide_out, "narrow in => narrow out");
2000 Node* narrow_mem = memory(adr_type);
2001 prev_mem = reset_memory();
2002 map()->set_memory(narrow_mem);
2003 set_predefined_input_for_runtime_call(call);
2004 }
2005
2006 // Hook each parm in order. Stop looking at the first NULL.
2007 if (parm0 != NULL) { call->init_req(TypeFunc::Parms+0, parm0);
2008 if (parm1 != NULL) { call->init_req(TypeFunc::Parms+1, parm1);
2009 if (parm2 != NULL) { call->init_req(TypeFunc::Parms+2, parm2);
2010 if (parm3 != NULL) { call->init_req(TypeFunc::Parms+3, parm3);
2011 if (parm4 != NULL) { call->init_req(TypeFunc::Parms+4, parm4);
2012 if (parm5 != NULL) { call->init_req(TypeFunc::Parms+5, parm5);
2013 if (parm6 != NULL) { call->init_req(TypeFunc::Parms+6, parm6);
2014 if (parm7 != NULL) { call->init_req(TypeFunc::Parms+7, parm7);
2015 /* close each nested if ===> */ } } } } } } } }
2016 assert(call->in(call->req()-1) != NULL, "must initialize all parms");
2017
2018 if (!is_leaf) {
2019 // Non-leaves can block and take safepoints:
2020 add_safepoint_edges(call, ((flags & RC_MUST_THROW) != 0));
2021 }
2022 // Non-leaves can throw exceptions:
2023 if (has_io) {
2024 call->set_req(TypeFunc::I_O, i_o());
2025 }
2026
2027 if (flags & RC_UNCOMMON) {
2028 // Set the count to a tiny probability. Cf. Estimate_Block_Frequency.
2029 // (An "if" probability corresponds roughly to an unconditional count.
2030 // Sort of.)
2031 call->set_cnt(PROB_UNLIKELY_MAG(4));
2032 }
2033
2034 Node* c = _gvn.transform(call);
2035 assert(c == call, "cannot disappear");
2036
2037 if (wide_out) {
2038 // Slow path call has full side-effects.
2039 set_predefined_output_for_runtime_call(call);
2040 } else {
2041 // Slow path call has few side-effects, and/or sets few values.
2042 set_predefined_output_for_runtime_call(call, prev_mem, adr_type);
2043 }
2044
2045 if (has_io) {
2046 set_i_o(_gvn.transform(new (C, 1) ProjNode(call, TypeFunc::I_O)));
2047 }
2048 return call;
2049
2050 }
2051
2052 //------------------------------merge_memory-----------------------------------
2053 // Merge memory from one path into the current memory state.
2054 void GraphKit::merge_memory(Node* new_mem, Node* region, int new_path) {
2055 for (MergeMemStream mms(merged_memory(), new_mem->as_MergeMem()); mms.next_non_empty2(); ) {
2056 Node* old_slice = mms.force_memory();
2057 Node* new_slice = mms.memory2();
2058 if (old_slice != new_slice) {
2059 PhiNode* phi;
2060 if (new_slice->is_Phi() && new_slice->as_Phi()->region() == region) {
2061 phi = new_slice->as_Phi();
2062 #ifdef ASSERT
2063 if (old_slice->is_Phi() && old_slice->as_Phi()->region() == region)
2064 old_slice = old_slice->in(new_path);
2065 // Caller is responsible for ensuring that any pre-existing
2066 // phis are already aware of old memory.
2067 int old_path = (new_path > 1) ? 1 : 2; // choose old_path != new_path
2068 assert(phi->in(old_path) == old_slice, "pre-existing phis OK");
2069 #endif
2070 mms.set_memory(phi);
2071 } else {
2072 phi = PhiNode::make(region, old_slice, Type::MEMORY, mms.adr_type(C));
2073 _gvn.set_type(phi, Type::MEMORY);
2074 phi->set_req(new_path, new_slice);
2075 mms.set_memory(_gvn.transform(phi)); // assume it is complete
2076 }
2077 }
2078 }
2079 }
2080
2081 //------------------------------make_slow_call_ex------------------------------
2082 // Make the exception handler hookups for the slow call
2083 void GraphKit::make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj) {
2084 if (stopped()) return;
2085
2086 // Make a catch node with just two handlers: fall-through and catch-all
2087 Node* i_o = _gvn.transform( new (C, 1) ProjNode(call, TypeFunc::I_O, separate_io_proj) );
2088 Node* catc = _gvn.transform( new (C, 2) CatchNode(control(), i_o, 2) );
2089 Node* norm = _gvn.transform( new (C, 1) CatchProjNode(catc, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci) );
2090 Node* excp = _gvn.transform( new (C, 1) CatchProjNode(catc, CatchProjNode::catch_all_index, CatchProjNode::no_handler_bci) );
2091
2092 { PreserveJVMState pjvms(this);
2093 set_control(excp);
2094 set_i_o(i_o);
2095
2096 if (excp != top()) {
2097 // Create an exception state also.
2098 // Use an exact type if the caller has specified a specific exception.
2099 const Type* ex_type = TypeOopPtr::make_from_klass_unique(ex_klass)->cast_to_ptr_type(TypePtr::NotNull);
2100 Node* ex_oop = new (C, 2) CreateExNode(ex_type, control(), i_o);
2101 add_exception_state(make_exception_state(_gvn.transform(ex_oop)));
2102 }
2103 }
2104
2105 // Get the no-exception control from the CatchNode.
2106 set_control(norm);
2107 }
2108
2109
2110 //-------------------------------gen_subtype_check-----------------------------
2111 // Generate a subtyping check. Takes as input the subtype and supertype.
2112 // Returns 2 values: sets the default control() to the true path and returns
2113 // the false path. Only reads invariant memory; sets no (visible) memory.
2114 // The PartialSubtypeCheckNode sets the hidden 1-word cache in the encoding
2115 // but that's not exposed to the optimizer. This call also doesn't take in an
2116 // Object; if you wish to check an Object you need to load the Object's class
2117 // prior to coming here.
2118 Node* GraphKit::gen_subtype_check(Node* subklass, Node* superklass) {
2119 // Fast check for identical types, perhaps identical constants.
2120 // The types can even be identical non-constants, in cases
2121 // involving Array.newInstance, Object.clone, etc.
2122 if (subklass == superklass)
2123 return top(); // false path is dead; no test needed.
2124
2125 if (_gvn.type(superklass)->singleton()) {
2126 ciKlass* superk = _gvn.type(superklass)->is_klassptr()->klass();
2127 ciKlass* subk = _gvn.type(subklass)->is_klassptr()->klass();
2128
2129 // In the common case of an exact superklass, try to fold up the
2130 // test before generating code. You may ask, why not just generate
2131 // the code and then let it fold up? The answer is that the generated
2132 // code will necessarily include null checks, which do not always
2133 // completely fold away. If they are also needless, then they turn
2134 // into a performance loss. Example:
2135 // Foo[] fa = blah(); Foo x = fa[0]; fa[1] = x;
2136 // Here, the type of 'fa' is often exact, so the store check
2137 // of fa[1]=x will fold up, without testing the nullness of x.
2138 switch (static_subtype_check(superk, subk)) {
2139 case SSC_always_false:
2140 {
2141 Node* always_fail = control();
2142 set_control(top());
2143 return always_fail;
2144 }
2145 case SSC_always_true:
2146 return top();
2147 case SSC_easy_test:
2148 {
2149 // Just do a direct pointer compare and be done.
2150 Node* cmp = _gvn.transform( new(C, 3) CmpPNode(subklass, superklass) );
2151 Node* bol = _gvn.transform( new(C, 2) BoolNode(cmp, BoolTest::eq) );
2152 IfNode* iff = create_and_xform_if(control(), bol, PROB_STATIC_FREQUENT, COUNT_UNKNOWN);
2153 set_control( _gvn.transform( new(C, 1) IfTrueNode (iff) ) );
2154 return _gvn.transform( new(C, 1) IfFalseNode(iff) );
2155 }
2156 case SSC_full_test:
2157 break;
2158 default:
2159 ShouldNotReachHere();
2160 }
2161 }
2162
2163 // %%% Possible further optimization: Even if the superklass is not exact,
2164 // if the subklass is the unique subtype of the superklass, the check
2165 // will always succeed. We could leave a dependency behind to ensure this.
2166
2167 // First load the super-klass's check-offset
2168 Node *p1 = basic_plus_adr( superklass, superklass, sizeof(oopDesc) + Klass::super_check_offset_offset_in_bytes() );
2169 Node *chk_off = _gvn.transform( new (C, 3) LoadINode( NULL, memory(p1), p1, _gvn.type(p1)->is_ptr() ) );
2170 int cacheoff_con = sizeof(oopDesc) + Klass::secondary_super_cache_offset_in_bytes();
2171 bool might_be_cache = (find_int_con(chk_off, cacheoff_con) == cacheoff_con);
2172
2173 // Load from the sub-klass's super-class display list, or a 1-word cache of
2174 // the secondary superclass list, or a failing value with a sentinel offset
2175 // if the super-klass is an interface or exceptionally deep in the Java
2176 // hierarchy and we have to scan the secondary superclass list the hard way.
2177 // Worst-case type is a little odd: NULL is allowed as a result (usually
2178 // klass loads can never produce a NULL).
2179 Node *chk_off_X = ConvI2X(chk_off);
2180 Node *p2 = _gvn.transform( new (C, 4) AddPNode(subklass,subklass,chk_off_X) );
2181 // For some types like interfaces the following loadKlass is from a 1-word
2182 // cache which is mutable so can't use immutable memory. Other
2183 // types load from the super-class display table which is immutable.
2184 Node *kmem = might_be_cache ? memory(p2) : immutable_memory();
2185 Node *nkls = _gvn.transform( LoadKlassNode::make( _gvn, kmem, p2, _gvn.type(p2)->is_ptr(), TypeKlassPtr::OBJECT_OR_NULL ) );
2186
2187 // Compile speed common case: ARE a subtype and we canNOT fail
2188 if( superklass == nkls )
2189 return top(); // false path is dead; no test needed.
2190
2191 // See if we get an immediate positive hit. Happens roughly 83% of the
2192 // time. Test to see if the value loaded just previously from the subklass
2193 // is exactly the superklass.
2194 Node *cmp1 = _gvn.transform( new (C, 3) CmpPNode( superklass, nkls ) );
2195 Node *bol1 = _gvn.transform( new (C, 2) BoolNode( cmp1, BoolTest::eq ) );
2196 IfNode *iff1 = create_and_xform_if( control(), bol1, PROB_LIKELY(0.83f), COUNT_UNKNOWN );
2197 Node *iftrue1 = _gvn.transform( new (C, 1) IfTrueNode ( iff1 ) );
2198 set_control( _gvn.transform( new (C, 1) IfFalseNode( iff1 ) ) );
2199
2200 // Compile speed common case: Check for being deterministic right now. If
2201 // chk_off is a constant and not equal to cacheoff then we are NOT a
2202 // subklass. In this case we need exactly the 1 test above and we can
2203 // return those results immediately.
2204 if (!might_be_cache) {
2205 Node* not_subtype_ctrl = control();
2206 set_control(iftrue1); // We need exactly the 1 test above
2207 return not_subtype_ctrl;
2208 }
2209
2210 // Gather the various success & failures here
2211 RegionNode *r_ok_subtype = new (C, 4) RegionNode(4);
2212 record_for_igvn(r_ok_subtype);
2213 RegionNode *r_not_subtype = new (C, 3) RegionNode(3);
2214 record_for_igvn(r_not_subtype);
2215
2216 r_ok_subtype->init_req(1, iftrue1);
2217
2218 // Check for immediate negative hit. Happens roughly 11% of the time (which
2219 // is roughly 63% of the remaining cases). Test to see if the loaded
2220 // check-offset points into the subklass display list or the 1-element
2221 // cache. If it points to the display (and NOT the cache) and the display
2222 // missed then it's not a subtype.
2223 Node *cacheoff = _gvn.intcon(cacheoff_con);
2224 Node *cmp2 = _gvn.transform( new (C, 3) CmpINode( chk_off, cacheoff ) );
2225 Node *bol2 = _gvn.transform( new (C, 2) BoolNode( cmp2, BoolTest::ne ) );
2226 IfNode *iff2 = create_and_xform_if( control(), bol2, PROB_LIKELY(0.63f), COUNT_UNKNOWN );
2227 r_not_subtype->init_req(1, _gvn.transform( new (C, 1) IfTrueNode (iff2) ) );
2228 set_control( _gvn.transform( new (C, 1) IfFalseNode(iff2) ) );
2229
2230 // Check for self. Very rare to get here, but it is taken 1/3 the time.
2231 // No performance impact (too rare) but allows sharing of secondary arrays
2232 // which has some footprint reduction.
2233 Node *cmp3 = _gvn.transform( new (C, 3) CmpPNode( subklass, superklass ) );
2234 Node *bol3 = _gvn.transform( new (C, 2) BoolNode( cmp3, BoolTest::eq ) );
2235 IfNode *iff3 = create_and_xform_if( control(), bol3, PROB_LIKELY(0.36f), COUNT_UNKNOWN );
2236 r_ok_subtype->init_req(2, _gvn.transform( new (C, 1) IfTrueNode ( iff3 ) ) );
2237 set_control( _gvn.transform( new (C, 1) IfFalseNode( iff3 ) ) );
2238
2239 // -- Roads not taken here: --
2240 // We could also have chosen to perform the self-check at the beginning
2241 // of this code sequence, as the assembler does. This would not pay off
2242 // the same way, since the optimizer, unlike the assembler, can perform
2243 // static type analysis to fold away many successful self-checks.
2244 // Non-foldable self checks work better here in second position, because
2245 // the initial primary superclass check subsumes a self-check for most
2246 // types. An exception would be a secondary type like array-of-interface,
2247 // which does not appear in its own primary supertype display.
2248 // Finally, we could have chosen to move the self-check into the
2249 // PartialSubtypeCheckNode, and from there out-of-line in a platform
2250 // dependent manner. But it is worthwhile to have the check here,
2251 // where it can be perhaps be optimized. The cost in code space is
2252 // small (register compare, branch).
2253
2254 // Now do a linear scan of the secondary super-klass array. Again, no real
2255 // performance impact (too rare) but it's gotta be done.
2256 // Since the code is rarely used, there is no penalty for moving it
2257 // out of line, and it can only improve I-cache density.
2258 // The decision to inline or out-of-line this final check is platform
2259 // dependent, and is found in the AD file definition of PartialSubtypeCheck.
2260 Node* psc = _gvn.transform(
2261 new (C, 3) PartialSubtypeCheckNode(control(), subklass, superklass) );
2262
2263 Node *cmp4 = _gvn.transform( new (C, 3) CmpPNode( psc, null() ) );
2264 Node *bol4 = _gvn.transform( new (C, 2) BoolNode( cmp4, BoolTest::ne ) );
2265 IfNode *iff4 = create_and_xform_if( control(), bol4, PROB_FAIR, COUNT_UNKNOWN );
2266 r_not_subtype->init_req(2, _gvn.transform( new (C, 1) IfTrueNode (iff4) ) );
2267 r_ok_subtype ->init_req(3, _gvn.transform( new (C, 1) IfFalseNode(iff4) ) );
2268
2269 // Return false path; set default control to true path.
2270 set_control( _gvn.transform(r_ok_subtype) );
2271 return _gvn.transform(r_not_subtype);
2272 }
2273
2274 //----------------------------static_subtype_check-----------------------------
2275 // Shortcut important common cases when superklass is exact:
2276 // (0) superklass is java.lang.Object (can occur in reflective code)
2277 // (1) subklass is already limited to a subtype of superklass => always ok
2278 // (2) subklass does not overlap with superklass => always fail
2279 // (3) superklass has NO subtypes and we can check with a simple compare.
2280 int GraphKit::static_subtype_check(ciKlass* superk, ciKlass* subk) {
2281 if (StressReflectiveCode) {
2282 return SSC_full_test; // Let caller generate the general case.
2283 }
2284
2285 if (superk == env()->Object_klass()) {
2286 return SSC_always_true; // (0) this test cannot fail
2287 }
2288
2289 ciType* superelem = superk;
2290 if (superelem->is_array_klass())
2291 superelem = superelem->as_array_klass()->base_element_type();
2292
2293 if (!subk->is_interface()) { // cannot trust static interface types yet
2294 if (subk->is_subtype_of(superk)) {
2295 return SSC_always_true; // (1) false path dead; no dynamic test needed
2296 }
2297 if (!(superelem->is_klass() && superelem->as_klass()->is_interface()) &&
2298 !superk->is_subtype_of(subk)) {
2299 return SSC_always_false;
2300 }
2301 }
2302
2303 // If casting to an instance klass, it must have no subtypes
2304 if (superk->is_interface()) {
2305 // Cannot trust interfaces yet.
2306 // %%% S.B. superk->nof_implementors() == 1
2307 } else if (superelem->is_instance_klass()) {
2308 ciInstanceKlass* ik = superelem->as_instance_klass();
2309 if (!ik->has_subklass() && !ik->is_interface()) {
2310 if (!ik->is_final()) {
2311 // Add a dependency if there is a chance of a later subclass.
2312 C->dependencies()->assert_leaf_type(ik);
2313 }
2314 return SSC_easy_test; // (3) caller can do a simple ptr comparison
2315 }
2316 } else {
2317 // A primitive array type has no subtypes.
2318 return SSC_easy_test; // (3) caller can do a simple ptr comparison
2319 }
2320
2321 return SSC_full_test;
2322 }
2323
2324 // Profile-driven exact type check:
2325 Node* GraphKit::type_check_receiver(Node* receiver, ciKlass* klass,
2326 float prob,
2327 Node* *casted_receiver) {
2328 const TypeKlassPtr* tklass = TypeKlassPtr::make(klass);
2329 Node* recv_klass = load_object_klass(receiver);
2330 Node* want_klass = makecon(tklass);
2331 Node* cmp = _gvn.transform( new(C, 3) CmpPNode(recv_klass, want_klass) );
2332 Node* bol = _gvn.transform( new(C, 2) BoolNode(cmp, BoolTest::eq) );
2333 IfNode* iff = create_and_xform_if(control(), bol, prob, COUNT_UNKNOWN);
2334 set_control( _gvn.transform( new(C, 1) IfTrueNode (iff) ));
2335 Node* fail = _gvn.transform( new(C, 1) IfFalseNode(iff) );
2336
2337 const TypeOopPtr* recv_xtype = tklass->as_instance_type();
2338 assert(recv_xtype->klass_is_exact(), "");
2339
2340 // Subsume downstream occurrences of receiver with a cast to
2341 // recv_xtype, since now we know what the type will be.
2342 Node* cast = new(C, 2) CheckCastPPNode(control(), receiver, recv_xtype);
2343 (*casted_receiver) = _gvn.transform(cast);
2344 // (User must make the replace_in_map call.)
2345
2346 return fail;
2347 }
2348
2349
2350 //-------------------------------gen_instanceof--------------------------------
2351 // Generate an instance-of idiom. Used by both the instance-of bytecode
2352 // and the reflective instance-of call.
2353 Node* GraphKit::gen_instanceof( Node *subobj, Node* superklass ) {
2354 C->set_has_split_ifs(true); // Has chance for split-if optimization
2355 assert( !stopped(), "dead parse path should be checked in callers" );
2356 assert(!TypePtr::NULL_PTR->higher_equal(_gvn.type(superklass)->is_klassptr()),
2357 "must check for not-null not-dead klass in callers");
2358
2359 // Make the merge point
2360 enum { _obj_path = 1, _fail_path, _null_path, PATH_LIMIT };
2361 RegionNode* region = new(C, PATH_LIMIT) RegionNode(PATH_LIMIT);
2362 Node* phi = new(C, PATH_LIMIT) PhiNode(region, TypeInt::BOOL);
2363 C->set_has_split_ifs(true); // Has chance for split-if optimization
2364
2365 // Null check; get casted pointer; set region slot 3
2366 Node* null_ctl = top();
2367 Node* not_null_obj = null_check_oop(subobj, &null_ctl);
2368
2369 // If not_null_obj is dead, only null-path is taken
2370 if (stopped()) { // Doing instance-of on a NULL?
2371 set_control(null_ctl);
2372 return intcon(0);
2373 }
2374 region->init_req(_null_path, null_ctl);
2375 phi ->init_req(_null_path, intcon(0)); // Set null path value
2376
2377 // Load the object's klass
2378 Node* obj_klass = load_object_klass(not_null_obj);
2379
2380 // Generate the subtype check
2381 Node* not_subtype_ctrl = gen_subtype_check(obj_klass, superklass);
2382
2383 // Plug in the success path to the general merge in slot 1.
2384 region->init_req(_obj_path, control());
2385 phi ->init_req(_obj_path, intcon(1));
2386
2387 // Plug in the failing path to the general merge in slot 2.
2388 region->init_req(_fail_path, not_subtype_ctrl);
2389 phi ->init_req(_fail_path, intcon(0));
2390
2391 // Return final merged results
2392 set_control( _gvn.transform(region) );
2393 record_for_igvn(region);
2394 return _gvn.transform(phi);
2395 }
2396
2397 //-------------------------------gen_checkcast---------------------------------
2398 // Generate a checkcast idiom. Used by both the checkcast bytecode and the
2399 // array store bytecode. Stack must be as-if BEFORE doing the bytecode so the
2400 // uncommon-trap paths work. Adjust stack after this call.
2401 // If failure_control is supplied and not null, it is filled in with
2402 // the control edge for the cast failure. Otherwise, an appropriate
2403 // uncommon trap or exception is thrown.
2404 Node* GraphKit::gen_checkcast(Node *obj, Node* superklass,
2405 Node* *failure_control) {
2406 kill_dead_locals(); // Benefit all the uncommon traps
2407 const TypeKlassPtr *tk = _gvn.type(superklass)->is_klassptr();
2408 const Type *toop = TypeOopPtr::make_from_klass(tk->klass());
2409
2410 // Fast cutout: Check the case that the cast is vacuously true.
2411 // This detects the common cases where the test will short-circuit
2412 // away completely. We do this before we perform the null check,
2413 // because if the test is going to turn into zero code, we don't
2414 // want a residual null check left around. (Causes a slowdown,
2415 // for example, in some objArray manipulations, such as a[i]=a[j].)
2416 if (tk->singleton()) {
2417 const TypeOopPtr* objtp = _gvn.type(obj)->isa_oopptr();
2418 if (objtp != NULL && objtp->klass() != NULL) {
2419 switch (static_subtype_check(tk->klass(), objtp->klass())) {
2420 case SSC_always_true:
2421 return obj;
2422 case SSC_always_false:
2423 // It needs a null check because a null will *pass* the cast check.
2424 // A non-null value will always produce an exception.
2425 return do_null_assert(obj, T_OBJECT);
2426 }
2427 }
2428 }
2429
2430 ciProfileData* data = NULL;
2431 if (failure_control == NULL) { // use MDO in regular case only
2432 assert(java_bc() == Bytecodes::_aastore ||
2433 java_bc() == Bytecodes::_checkcast,
2434 "interpreter profiles type checks only for these BCs");
2435 data = method()->method_data()->bci_to_data(bci());
2436 }
2437
2438 // Make the merge point
2439 enum { _obj_path = 1, _null_path, PATH_LIMIT };
2440 RegionNode* region = new (C, PATH_LIMIT) RegionNode(PATH_LIMIT);
2441 Node* phi = new (C, PATH_LIMIT) PhiNode(region, toop);
2442 C->set_has_split_ifs(true); // Has chance for split-if optimization
2443
2444 // Use null-cast information if it is available
2445 bool never_see_null = false;
2446 // If we see an unexpected null at a check-cast we record it and force a
2447 // recompile; the offending check-cast will be compiled to handle NULLs.
2448 // If we see several offending BCIs, then all checkcasts in the
2449 // method will be compiled to handle NULLs.
2450 if (UncommonNullCast // Cutout for this technique
2451 && failure_control == NULL // regular case
2452 && obj != null() // And not the -Xcomp stupid case?
2453 && !too_many_traps(Deoptimization::Reason_null_check)) {
2454 // Finally, check the "null_seen" bit from the interpreter.
2455 if (data == NULL || !data->as_BitData()->null_seen()) {
2456 never_see_null = true;
2457 }
2458 }
2459
2460 // Null check; get casted pointer; set region slot 3
2461 Node* null_ctl = top();
2462 Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null);
2463
2464 // If not_null_obj is dead, only null-path is taken
2465 if (stopped()) { // Doing instance-of on a NULL?
2466 set_control(null_ctl);
2467 return null();
2468 }
2469 region->init_req(_null_path, null_ctl);
2470 phi ->init_req(_null_path, null()); // Set null path value
2471
2472 Node* cast_obj = NULL; // the casted version of the object
2473
2474 // If the profile has seen exactly one type, narrow to that type.
2475 // (The subsequent subtype check will always fold up.)
2476 if (UseTypeProfile && TypeProfileCasts && data != NULL &&
2477 // Counter has never been decremented (due to cast failure).
2478 // ...This is a reasonable thing to expect. It is true of
2479 // all casts inserted by javac to implement generic types.
2480 data->as_CounterData()->count() >= 0 &&
2481 !too_many_traps(Deoptimization::Reason_class_check)) {
2482 // (No, this isn't a call, but it's enough like a virtual call
2483 // to use the same ciMethod accessor to get the profile info...)
2484 ciCallProfile profile = method()->call_profile_at_bci(bci());
2485 if (profile.count() >= 0 && // no cast failures here
2486 profile.has_receiver(0) &&
2487 profile.morphism() == 1) {
2488 ciKlass* exact_kls = profile.receiver(0);
2489 int ssc = static_subtype_check(tk->klass(), exact_kls);
2490 if (ssc == SSC_always_true) {
2491 // If we narrow the type to match what the type profile sees,
2492 // we can then remove the rest of the cast.
2493 // This is a win, even if the exact_kls is very specific,
2494 // because downstream operations, such as method calls,
2495 // will often benefit from the sharper type.
2496 Node* exact_obj = not_null_obj; // will get updated in place...
2497 Node* slow_ctl = type_check_receiver(exact_obj, exact_kls, 1.0,
2498 &exact_obj);
2499 { PreserveJVMState pjvms(this);
2500 set_control(slow_ctl);
2501 uncommon_trap(Deoptimization::Reason_class_check,
2502 Deoptimization::Action_maybe_recompile);
2503 }
2504 if (failure_control != NULL) // failure is now impossible
2505 (*failure_control) = top();
2506 replace_in_map(not_null_obj, exact_obj);
2507 // adjust the type of the phi to the exact klass:
2508 phi->raise_bottom_type(_gvn.type(exact_obj)->meet(TypePtr::NULL_PTR));
2509 cast_obj = exact_obj;
2510 }
2511 // assert(cast_obj != NULL)... except maybe the profile lied to us.
2512 }
2513 }
2514
2515 if (cast_obj == NULL) {
2516 // Load the object's klass
2517 Node* obj_klass = load_object_klass(not_null_obj);
2518
2519 // Generate the subtype check
2520 Node* not_subtype_ctrl = gen_subtype_check( obj_klass, superklass );
2521
2522 // Plug in success path into the merge
2523 cast_obj = _gvn.transform(new (C, 2) CheckCastPPNode(control(),
2524 not_null_obj, toop));
2525 // Failure path ends in uncommon trap (or may be dead - failure impossible)
2526 if (failure_control == NULL) {
2527 if (not_subtype_ctrl != top()) { // If failure is possible
2528 PreserveJVMState pjvms(this);
2529 set_control(not_subtype_ctrl);
2530 builtin_throw(Deoptimization::Reason_class_check, obj_klass);
2531 }
2532 } else {
2533 (*failure_control) = not_subtype_ctrl;
2534 }
2535 }
2536
2537 region->init_req(_obj_path, control());
2538 phi ->init_req(_obj_path, cast_obj);
2539
2540 // A merge of NULL or Casted-NotNull obj
2541 Node* res = _gvn.transform(phi);
2542
2543 // Note I do NOT always 'replace_in_map(obj,result)' here.
2544 // if( tk->klass()->can_be_primary_super() )
2545 // This means that if I successfully store an Object into an array-of-String
2546 // I 'forget' that the Object is really now known to be a String. I have to
2547 // do this because we don't have true union types for interfaces - if I store
2548 // a Baz into an array-of-Interface and then tell the optimizer it's an
2549 // Interface, I forget that it's also a Baz and cannot do Baz-like field
2550 // references to it. FIX THIS WHEN UNION TYPES APPEAR!
2551 // replace_in_map( obj, res );
2552
2553 // Return final merged results
2554 set_control( _gvn.transform(region) );
2555 record_for_igvn(region);
2556 return res;
2557 }
2558
2559 //------------------------------next_monitor-----------------------------------
2560 // What number should be given to the next monitor?
2561 int GraphKit::next_monitor() {
2562 int current = jvms()->monitor_depth()* C->sync_stack_slots();
2563 int next = current + C->sync_stack_slots();
2564 // Keep the toplevel high water mark current:
2565 if (C->fixed_slots() < next) C->set_fixed_slots(next);
2566 return current;
2567 }
2568
2569 //------------------------------insert_mem_bar---------------------------------
2570 // Memory barrier to avoid floating things around
2571 // The membar serves as a pinch point between both control and all memory slices.
2572 Node* GraphKit::insert_mem_bar(int opcode, Node* precedent) {
2573 MemBarNode* mb = MemBarNode::make(C, opcode, Compile::AliasIdxBot, precedent);
2574 mb->init_req(TypeFunc::Control, control());
2575 mb->init_req(TypeFunc::Memory, reset_memory());
2576 Node* membar = _gvn.transform(mb);
2577 set_control(_gvn.transform(new (C, 1) ProjNode(membar,TypeFunc::Control) ));
2578 set_all_memory_call(membar);
2579 return membar;
2580 }
2581
2582 //-------------------------insert_mem_bar_volatile----------------------------
2583 // Memory barrier to avoid floating things around
2584 // The membar serves as a pinch point between both control and memory(alias_idx).
2585 // If you want to make a pinch point on all memory slices, do not use this
2586 // function (even with AliasIdxBot); use insert_mem_bar() instead.
2587 Node* GraphKit::insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent) {
2588 // When Parse::do_put_xxx updates a volatile field, it appends a series
2589 // of MemBarVolatile nodes, one for *each* volatile field alias category.
2590 // The first membar is on the same memory slice as the field store opcode.
2591 // This forces the membar to follow the store. (Bug 6500685 broke this.)
2592 // All the other membars (for other volatile slices, including AliasIdxBot,
2593 // which stands for all unknown volatile slices) are control-dependent
2594 // on the first membar. This prevents later volatile loads or stores
2595 // from sliding up past the just-emitted store.
2596
2597 MemBarNode* mb = MemBarNode::make(C, opcode, alias_idx, precedent);
2598 mb->set_req(TypeFunc::Control,control());
2599 if (alias_idx == Compile::AliasIdxBot) {
2600 mb->set_req(TypeFunc::Memory, merged_memory()->base_memory());
2601 } else {
2602 assert(!(opcode == Op_Initialize && alias_idx != Compile::AliasIdxRaw), "fix caller");
2603 mb->set_req(TypeFunc::Memory, memory(alias_idx));
2604 }
2605 Node* membar = _gvn.transform(mb);
2606 set_control(_gvn.transform(new (C, 1) ProjNode(membar, TypeFunc::Control)));
2607 if (alias_idx == Compile::AliasIdxBot) {
2608 merged_memory()->set_base_memory(_gvn.transform(new (C, 1) ProjNode(membar, TypeFunc::Memory)));
2609 } else {
2610 set_memory(_gvn.transform(new (C, 1) ProjNode(membar, TypeFunc::Memory)),alias_idx);
2611 }
2612 return membar;
2613 }
2614
2615 //------------------------------shared_lock------------------------------------
2616 // Emit locking code.
2617 FastLockNode* GraphKit::shared_lock(Node* obj) {
2618 // bci is either a monitorenter bc or InvocationEntryBci
2619 // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
2620 assert(SynchronizationEntryBCI == InvocationEntryBci, "");
2621
2622 if( !GenerateSynchronizationCode )
2623 return NULL; // Not locking things?
2624 if (stopped()) // Dead monitor?
2625 return NULL;
2626
2627 assert(dead_locals_are_killed(), "should kill locals before sync. point");
2628
2629 // Box the stack location
2630 Node* box = _gvn.transform(new (C, 1) BoxLockNode(next_monitor()));
2631 Node* mem = reset_memory();
2632
2633 FastLockNode * flock = _gvn.transform(new (C, 3) FastLockNode(0, obj, box) )->as_FastLock();
2634 if (PrintPreciseBiasedLockingStatistics) {
2635 // Create the counters for this fast lock.
2636 flock->create_lock_counter(sync_jvms()); // sync_jvms used to get current bci
2637 }
2638 // Add monitor to debug info for the slow path. If we block inside the
2639 // slow path and de-opt, we need the monitor hanging around
2640 map()->push_monitor( flock );
2641
2642 const TypeFunc *tf = LockNode::lock_type();
2643 LockNode *lock = new (C, tf->domain()->cnt()) LockNode(C, tf);
2644
2645 lock->init_req( TypeFunc::Control, control() );
2646 lock->init_req( TypeFunc::Memory , mem );
2647 lock->init_req( TypeFunc::I_O , top() ) ; // does no i/o
2648 lock->init_req( TypeFunc::FramePtr, frameptr() );
2649 lock->init_req( TypeFunc::ReturnAdr, top() );
2650
2651 lock->init_req(TypeFunc::Parms + 0, obj);
2652 lock->init_req(TypeFunc::Parms + 1, box);
2653 lock->init_req(TypeFunc::Parms + 2, flock);
2654 add_safepoint_edges(lock);
2655
2656 lock = _gvn.transform( lock )->as_Lock();
2657
2658 // lock has no side-effects, sets few values
2659 set_predefined_output_for_runtime_call(lock, mem, TypeRawPtr::BOTTOM);
2660
2661 insert_mem_bar(Op_MemBarAcquire);
2662
2663 // Add this to the worklist so that the lock can be eliminated
2664 record_for_igvn(lock);
2665
2666 #ifndef PRODUCT
2667 if (PrintLockStatistics) {
2668 // Update the counter for this lock. Don't bother using an atomic
2669 // operation since we don't require absolute accuracy.
2670 lock->create_lock_counter(map()->jvms());
2671 int adr_type = Compile::AliasIdxRaw;
2672 Node* counter_addr = makecon(TypeRawPtr::make(lock->counter()->addr()));
2673 Node* cnt = make_load(NULL, counter_addr, TypeInt::INT, T_INT, adr_type);
2674 Node* incr = _gvn.transform(new (C, 3) AddINode(cnt, _gvn.intcon(1)));
2675 store_to_memory(control(), counter_addr, incr, T_INT, adr_type);
2676 }
2677 #endif
2678
2679 return flock;
2680 }
2681
2682
2683 //------------------------------shared_unlock----------------------------------
2684 // Emit unlocking code.
2685 void GraphKit::shared_unlock(Node* box, Node* obj) {
2686 // bci is either a monitorenter bc or InvocationEntryBci
2687 // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
2688 assert(SynchronizationEntryBCI == InvocationEntryBci, "");
2689
2690 if( !GenerateSynchronizationCode )
2691 return;
2692 if (stopped()) { // Dead monitor?
2693 map()->pop_monitor(); // Kill monitor from debug info
2694 return;
2695 }
2696
2697 // Memory barrier to avoid floating things down past the locked region
2698 insert_mem_bar(Op_MemBarRelease);
2699
2700 const TypeFunc *tf = OptoRuntime::complete_monitor_exit_Type();
2701 UnlockNode *unlock = new (C, tf->domain()->cnt()) UnlockNode(C, tf);
2702 uint raw_idx = Compile::AliasIdxRaw;
2703 unlock->init_req( TypeFunc::Control, control() );
2704 unlock->init_req( TypeFunc::Memory , memory(raw_idx) );
2705 unlock->init_req( TypeFunc::I_O , top() ) ; // does no i/o
2706 unlock->init_req( TypeFunc::FramePtr, frameptr() );
2707 unlock->init_req( TypeFunc::ReturnAdr, top() );
2708
2709 unlock->init_req(TypeFunc::Parms + 0, obj);
2710 unlock->init_req(TypeFunc::Parms + 1, box);
2711 unlock = _gvn.transform(unlock)->as_Unlock();
2712
2713 Node* mem = reset_memory();
2714
2715 // unlock has no side-effects, sets few values
2716 set_predefined_output_for_runtime_call(unlock, mem, TypeRawPtr::BOTTOM);
2717
2718 // Kill monitor from debug info
2719 map()->pop_monitor( );
2720 }
2721
2722 //-------------------------------get_layout_helper-----------------------------
2723 // If the given klass is a constant or known to be an array,
2724 // fetch the constant layout helper value into constant_value
2725 // and return (Node*)NULL. Otherwise, load the non-constant
2726 // layout helper value, and return the node which represents it.
2727 // This two-faced routine is useful because allocation sites
2728 // almost always feature constant types.
2729 Node* GraphKit::get_layout_helper(Node* klass_node, jint& constant_value) {
2730 const TypeKlassPtr* inst_klass = _gvn.type(klass_node)->isa_klassptr();
2731 if (!StressReflectiveCode && inst_klass != NULL) {
2732 ciKlass* klass = inst_klass->klass();
2733 bool xklass = inst_klass->klass_is_exact();
2734 if (xklass || klass->is_array_klass()) {
2735 jint lhelper = klass->layout_helper();
2736 if (lhelper != Klass::_lh_neutral_value) {
2737 constant_value = lhelper;
2738 return (Node*) NULL;
2739 }
2740 }
2741 }
2742 constant_value = Klass::_lh_neutral_value; // put in a known value
2743 Node* lhp = basic_plus_adr(klass_node, klass_node, Klass::layout_helper_offset_in_bytes() + sizeof(oopDesc));
2744 return make_load(NULL, lhp, TypeInt::INT, T_INT);
2745 }
2746
2747 // We just put in an allocate/initialize with a big raw-memory effect.
2748 // Hook selected additional alias categories on the initialization.
2749 static void hook_memory_on_init(GraphKit& kit, int alias_idx,
2750 MergeMemNode* init_in_merge,
2751 Node* init_out_raw) {
2752 DEBUG_ONLY(Node* init_in_raw = init_in_merge->base_memory());
2753 assert(init_in_merge->memory_at(alias_idx) == init_in_raw, "");
2754
2755 Node* prevmem = kit.memory(alias_idx);
2756 init_in_merge->set_memory_at(alias_idx, prevmem);
2757 kit.set_memory(init_out_raw, alias_idx);
2758 }
2759
2760 //---------------------------set_output_for_allocation-------------------------
2761 Node* GraphKit::set_output_for_allocation(AllocateNode* alloc,
2762 const TypeOopPtr* oop_type,
2763 bool raw_mem_only) {
2764 int rawidx = Compile::AliasIdxRaw;
2765 alloc->set_req( TypeFunc::FramePtr, frameptr() );
2766 add_safepoint_edges(alloc);
2767 Node* allocx = _gvn.transform(alloc);
2768 set_control( _gvn.transform(new (C, 1) ProjNode(allocx, TypeFunc::Control) ) );
2769 // create memory projection for i_o
2770 set_memory ( _gvn.transform( new (C, 1) ProjNode(allocx, TypeFunc::Memory, true) ), rawidx );
2771 make_slow_call_ex(allocx, env()->OutOfMemoryError_klass(), true);
2772
2773 // create a memory projection as for the normal control path
2774 Node* malloc = _gvn.transform(new (C, 1) ProjNode(allocx, TypeFunc::Memory));
2775 set_memory(malloc, rawidx);
2776
2777 // a normal slow-call doesn't change i_o, but an allocation does
2778 // we create a separate i_o projection for the normal control path
2779 set_i_o(_gvn.transform( new (C, 1) ProjNode(allocx, TypeFunc::I_O, false) ) );
2780 Node* rawoop = _gvn.transform( new (C, 1) ProjNode(allocx, TypeFunc::Parms) );
2781
2782 // put in an initialization barrier
2783 InitializeNode* init = insert_mem_bar_volatile(Op_Initialize, rawidx,
2784 rawoop)->as_Initialize();
2785 assert(alloc->initialization() == init, "2-way macro link must work");
2786 assert(init ->allocation() == alloc, "2-way macro link must work");
2787 if (ReduceFieldZeroing && !raw_mem_only) {
2788 // Extract memory strands which may participate in the new object's
2789 // initialization, and source them from the new InitializeNode.
2790 // This will allow us to observe initializations when they occur,
2791 // and link them properly (as a group) to the InitializeNode.
2792 assert(init->in(InitializeNode::Memory) == malloc, "");
2793 MergeMemNode* minit_in = MergeMemNode::make(C, malloc);
2794 init->set_req(InitializeNode::Memory, minit_in);
2795 record_for_igvn(minit_in); // fold it up later, if possible
2796 Node* minit_out = memory(rawidx);
2797 assert(minit_out->is_Proj() && minit_out->in(0) == init, "");
2798 if (oop_type->isa_aryptr()) {
2799 const TypePtr* telemref = oop_type->add_offset(Type::OffsetBot);
2800 int elemidx = C->get_alias_index(telemref);
2801 hook_memory_on_init(*this, elemidx, minit_in, minit_out);
2802 } else if (oop_type->isa_instptr()) {
2803 ciInstanceKlass* ik = oop_type->klass()->as_instance_klass();
2804 for (int i = 0, len = ik->nof_nonstatic_fields(); i < len; i++) {
2805 ciField* field = ik->nonstatic_field_at(i);
2806 if (field->offset() >= TrackedInitializationLimit * HeapWordSize)
2807 continue; // do not bother to track really large numbers of fields
2808 // Find (or create) the alias category for this field:
2809 int fieldidx = C->alias_type(field)->index();
2810 hook_memory_on_init(*this, fieldidx, minit_in, minit_out);
2811 }
2812 }
2813 }
2814
2815 // Cast raw oop to the real thing...
2816 Node* javaoop = new (C, 2) CheckCastPPNode(control(), rawoop, oop_type);
2817 javaoop = _gvn.transform(javaoop);
2818 C->set_recent_alloc(control(), javaoop);
2819 assert(just_allocated_object(control()) == javaoop, "just allocated");
2820
2821 #ifdef ASSERT
2822 { // Verify that the AllocateNode::Ideal_allocation recognizers work:
2823 assert(AllocateNode::Ideal_allocation(rawoop, &_gvn) == alloc,
2824 "Ideal_allocation works");
2825 assert(AllocateNode::Ideal_allocation(javaoop, &_gvn) == alloc,
2826 "Ideal_allocation works");
2827 if (alloc->is_AllocateArray()) {
2828 assert(AllocateArrayNode::Ideal_array_allocation(rawoop, &_gvn) == alloc->as_AllocateArray(),
2829 "Ideal_allocation works");
2830 assert(AllocateArrayNode::Ideal_array_allocation(javaoop, &_gvn) == alloc->as_AllocateArray(),
2831 "Ideal_allocation works");
2832 } else {
2833 assert(alloc->in(AllocateNode::ALength)->is_top(), "no length, please");
2834 }
2835 }
2836 #endif //ASSERT
2837
2838 return javaoop;
2839 }
2840
2841 //---------------------------new_instance--------------------------------------
2842 // This routine takes a klass_node which may be constant (for a static type)
2843 // or may be non-constant (for reflective code). It will work equally well
2844 // for either, and the graph will fold nicely if the optimizer later reduces
2845 // the type to a constant.
2846 // The optional arguments are for specialized use by intrinsics:
2847 // - If 'extra_slow_test' if not null is an extra condition for the slow-path.
2848 // - If 'raw_mem_only', do not cast the result to an oop.
2849 // - If 'return_size_val', report the the total object size to the caller.
2850 Node* GraphKit::new_instance(Node* klass_node,
2851 Node* extra_slow_test,
2852 bool raw_mem_only, // affect only raw memory
2853 Node* *return_size_val) {
2854 // Compute size in doublewords
2855 // The size is always an integral number of doublewords, represented
2856 // as a positive bytewise size stored in the klass's layout_helper.
2857 // The layout_helper also encodes (in a low bit) the need for a slow path.
2858 jint layout_con = Klass::_lh_neutral_value;
2859 Node* layout_val = get_layout_helper(klass_node, layout_con);
2860 int layout_is_con = (layout_val == NULL);
2861
2862 if (extra_slow_test == NULL) extra_slow_test = intcon(0);
2863 // Generate the initial go-slow test. It's either ALWAYS (return a
2864 // Node for 1) or NEVER (return a NULL) or perhaps (in the reflective
2865 // case) a computed value derived from the layout_helper.
2866 Node* initial_slow_test = NULL;
2867 if (layout_is_con) {
2868 assert(!StressReflectiveCode, "stress mode does not use these paths");
2869 bool must_go_slow = Klass::layout_helper_needs_slow_path(layout_con);
2870 initial_slow_test = must_go_slow? intcon(1): extra_slow_test;
2871
2872 } else { // reflective case
2873 // This reflective path is used by Unsafe.allocateInstance.
2874 // (It may be stress-tested by specifying StressReflectiveCode.)
2875 // Basically, we want to get into the VM is there's an illegal argument.
2876 Node* bit = intcon(Klass::_lh_instance_slow_path_bit);
2877 initial_slow_test = _gvn.transform( new (C, 3) AndINode(layout_val, bit) );
2878 if (extra_slow_test != intcon(0)) {
2879 initial_slow_test = _gvn.transform( new (C, 3) OrINode(initial_slow_test, extra_slow_test) );
2880 }
2881 // (Macro-expander will further convert this to a Bool, if necessary.)
2882 }
2883
2884 // Find the size in bytes. This is easy; it's the layout_helper.
2885 // The size value must be valid even if the slow path is taken.
2886 Node* size = NULL;
2887 if (layout_is_con) {
2888 size = MakeConX(Klass::layout_helper_size_in_bytes(layout_con));
2889 } else { // reflective case
2890 // This reflective path is used by clone and Unsafe.allocateInstance.
2891 size = ConvI2X(layout_val);
2892
2893 // Clear the low bits to extract layout_helper_size_in_bytes:
2894 assert((int)Klass::_lh_instance_slow_path_bit < BytesPerLong, "clear bit");
2895 Node* mask = MakeConX(~ (intptr_t)right_n_bits(LogBytesPerLong));
2896 size = _gvn.transform( new (C, 3) AndXNode(size, mask) );
2897 }
2898 if (return_size_val != NULL) {
2899 (*return_size_val) = size;
2900 }
2901
2902 // This is a precise notnull oop of the klass.
2903 // (Actually, it need not be precise if this is a reflective allocation.)
2904 // It's what we cast the result to.
2905 const TypeKlassPtr* tklass = _gvn.type(klass_node)->isa_klassptr();
2906 if (!tklass) tklass = TypeKlassPtr::OBJECT;
2907 const TypeOopPtr* oop_type = tklass->as_instance_type();
2908
2909 // Now generate allocation code
2910
2911 // The entire memory state is needed for slow path of the allocation
2912 // since GC and deoptimization can happened.
2913 Node *mem = reset_memory();
2914 set_all_memory(mem); // Create new memory state
2915
2916 AllocateNode* alloc
2917 = new (C, AllocateNode::ParmLimit)
2918 AllocateNode(C, AllocateNode::alloc_type(),
2919 control(), mem, i_o(),
2920 size, klass_node,
2921 initial_slow_test);
2922
2923 return set_output_for_allocation(alloc, oop_type, raw_mem_only);
2924 }
2925
2926 //-------------------------------new_array-------------------------------------
2927 // helper for both newarray and anewarray
2928 // The 'length' parameter is (obviously) the length of the array.
2929 // See comments on new_instance for the meaning of the other arguments.
2930 Node* GraphKit::new_array(Node* klass_node, // array klass (maybe variable)
2931 Node* length, // number of array elements
2932 int nargs, // number of arguments to push back for uncommon trap
2933 bool raw_mem_only, // affect only raw memory
2934 Node* *return_size_val) {
2935 jint layout_con = Klass::_lh_neutral_value;
2936 Node* layout_val = get_layout_helper(klass_node, layout_con);
2937 int layout_is_con = (layout_val == NULL);
2938
2939 if (!layout_is_con && !StressReflectiveCode &&
2940 !too_many_traps(Deoptimization::Reason_class_check)) {
2941 // This is a reflective array creation site.
2942 // Optimistically assume that it is a subtype of Object[],
2943 // so that we can fold up all the address arithmetic.
2944 layout_con = Klass::array_layout_helper(T_OBJECT);
2945 Node* cmp_lh = _gvn.transform( new(C, 3) CmpINode(layout_val, intcon(layout_con)) );
2946 Node* bol_lh = _gvn.transform( new(C, 2) BoolNode(cmp_lh, BoolTest::eq) );
2947 { BuildCutout unless(this, bol_lh, PROB_MAX);
2948 _sp += nargs;
2949 uncommon_trap(Deoptimization::Reason_class_check,
2950 Deoptimization::Action_maybe_recompile);
2951 }
2952 layout_val = NULL;
2953 layout_is_con = true;
2954 }
2955
2956 // Generate the initial go-slow test. Make sure we do not overflow
2957 // if length is huge (near 2Gig) or negative! We do not need
2958 // exact double-words here, just a close approximation of needed
2959 // double-words. We can't add any offset or rounding bits, lest we
2960 // take a size -1 of bytes and make it positive. Use an unsigned
2961 // compare, so negative sizes look hugely positive.
2962 int fast_size_limit = FastAllocateSizeLimit;
2963 if (layout_is_con) {
2964 assert(!StressReflectiveCode, "stress mode does not use these paths");
2965 // Increase the size limit if we have exact knowledge of array type.
2966 int log2_esize = Klass::layout_helper_log2_element_size(layout_con);
2967 fast_size_limit <<= (LogBytesPerLong - log2_esize);
2968 }
2969
2970 Node* initial_slow_cmp = _gvn.transform( new (C, 3) CmpUNode( length, intcon( fast_size_limit ) ) );
2971 Node* initial_slow_test = _gvn.transform( new (C, 2) BoolNode( initial_slow_cmp, BoolTest::gt ) );
2972 if (initial_slow_test->is_Bool()) {
2973 // Hide it behind a CMoveI, or else PhaseIdealLoop::split_up will get sick.
2974 initial_slow_test = initial_slow_test->as_Bool()->as_int_value(&_gvn);
2975 }
2976
2977 // --- Size Computation ---
2978 // array_size = round_to_heap(array_header + (length << elem_shift));
2979 // where round_to_heap(x) == round_to(x, MinObjAlignmentInBytes)
2980 // and round_to(x, y) == ((x + y-1) & ~(y-1))
2981 // The rounding mask is strength-reduced, if possible.
2982 int round_mask = MinObjAlignmentInBytes - 1;
2983 Node* header_size = NULL;
2984 int header_size_min = arrayOopDesc::base_offset_in_bytes(T_BYTE);
2985 // (T_BYTE has the weakest alignment and size restrictions...)
2986 if (layout_is_con) {
2987 int hsize = Klass::layout_helper_header_size(layout_con);
2988 int eshift = Klass::layout_helper_log2_element_size(layout_con);
2989 BasicType etype = Klass::layout_helper_element_type(layout_con);
2990 if ((round_mask & ~right_n_bits(eshift)) == 0)
2991 round_mask = 0; // strength-reduce it if it goes away completely
2992 assert((hsize & right_n_bits(eshift)) == 0, "hsize is pre-rounded");
2993 assert(header_size_min <= hsize, "generic minimum is smallest");
2994 header_size_min = hsize;
2995 header_size = intcon(hsize + round_mask);
2996 } else {
2997 Node* hss = intcon(Klass::_lh_header_size_shift);
2998 Node* hsm = intcon(Klass::_lh_header_size_mask);
2999 Node* hsize = _gvn.transform( new(C, 3) URShiftINode(layout_val, hss) );
3000 hsize = _gvn.transform( new(C, 3) AndINode(hsize, hsm) );
3001 Node* mask = intcon(round_mask);
3002 header_size = _gvn.transform( new(C, 3) AddINode(hsize, mask) );
3003 }
3004
3005 Node* elem_shift = NULL;
3006 if (layout_is_con) {
3007 int eshift = Klass::layout_helper_log2_element_size(layout_con);
3008 if (eshift != 0)
3009 elem_shift = intcon(eshift);
3010 } else {
3011 // There is no need to mask or shift this value.
3012 // The semantics of LShiftINode include an implicit mask to 0x1F.
3013 assert(Klass::_lh_log2_element_size_shift == 0, "use shift in place");
3014 elem_shift = layout_val;
3015 }
3016
3017 // Transition to native address size for all offset calculations:
3018 Node* lengthx = ConvI2X(length);
3019 Node* headerx = ConvI2X(header_size);
3020 #ifdef _LP64
3021 { const TypeLong* tllen = _gvn.find_long_type(lengthx);
3022 if (tllen != NULL && tllen->_lo < 0) {
3023 // Add a manual constraint to a positive range. Cf. array_element_address.
3024 jlong size_max = arrayOopDesc::max_array_length(T_BYTE);
3025 if (size_max > tllen->_hi) size_max = tllen->_hi;
3026 const TypeLong* tlcon = TypeLong::make(CONST64(0), size_max, Type::WidenMin);
3027 lengthx = _gvn.transform( new (C, 2) ConvI2LNode(length, tlcon));
3028 }
3029 }
3030 #endif
3031
3032 // Combine header size (plus rounding) and body size. Then round down.
3033 // This computation cannot overflow, because it is used only in two
3034 // places, one where the length is sharply limited, and the other
3035 // after a successful allocation.
3036 Node* abody = lengthx;
3037 if (elem_shift != NULL)
3038 abody = _gvn.transform( new(C, 3) LShiftXNode(lengthx, elem_shift) );
3039 Node* size = _gvn.transform( new(C, 3) AddXNode(headerx, abody) );
3040 if (round_mask != 0) {
3041 Node* mask = MakeConX(~round_mask);
3042 size = _gvn.transform( new(C, 3) AndXNode(size, mask) );
3043 }
3044 // else if round_mask == 0, the size computation is self-rounding
3045
3046 if (return_size_val != NULL) {
3047 // This is the size
3048 (*return_size_val) = size;
3049 }
3050
3051 // Now generate allocation code
3052
3053 // The entire memory state is needed for slow path of the allocation
3054 // since GC and deoptimization can happened.
3055 Node *mem = reset_memory();
3056 set_all_memory(mem); // Create new memory state
3057
3058 // Create the AllocateArrayNode and its result projections
3059 AllocateArrayNode* alloc
3060 = new (C, AllocateArrayNode::ParmLimit)
3061 AllocateArrayNode(C, AllocateArrayNode::alloc_type(),
3062 control(), mem, i_o(),
3063 size, klass_node,
3064 initial_slow_test,
3065 length);
3066
3067 // Cast to correct type. Note that the klass_node may be constant or not,
3068 // and in the latter case the actual array type will be inexact also.
3069 // (This happens via a non-constant argument to inline_native_newArray.)
3070 // In any case, the value of klass_node provides the desired array type.
3071 const TypeInt* length_type = _gvn.find_int_type(length);
3072 const TypeOopPtr* ary_type = _gvn.type(klass_node)->is_klassptr()->as_instance_type();
3073 if (ary_type->isa_aryptr() && length_type != NULL) {
3074 // Try to get a better type than POS for the size
3075 ary_type = ary_type->is_aryptr()->cast_to_size(length_type);
3076 }
3077
3078 Node* javaoop = set_output_for_allocation(alloc, ary_type, raw_mem_only);
3079
3080 // Cast length on remaining path to be as narrow as possible
3081 if (map()->find_edge(length) >= 0) {
3082 Node* ccast = alloc->make_ideal_length(ary_type, &_gvn);
3083 if (ccast != length) {
3084 _gvn.set_type_bottom(ccast);
3085 record_for_igvn(ccast);
3086 replace_in_map(length, ccast);
3087 }
3088 }
3089
3090 return javaoop;
3091 }
3092
3093 // The following "Ideal_foo" functions are placed here because they recognize
3094 // the graph shapes created by the functions immediately above.
3095
3096 //---------------------------Ideal_allocation----------------------------------
3097 // Given an oop pointer or raw pointer, see if it feeds from an AllocateNode.
3098 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase) {
3099 if (ptr == NULL) { // reduce dumb test in callers
3100 return NULL;
3101 }
3102 if (ptr->is_CheckCastPP()) { // strip a raw-to-oop cast
3103 ptr = ptr->in(1);
3104 if (ptr == NULL) return NULL;
3105 }
3106 if (ptr->is_Proj()) {
3107 Node* allo = ptr->in(0);
3108 if (allo != NULL && allo->is_Allocate()) {
3109 return allo->as_Allocate();
3110 }
3111 }
3112 // Report failure to match.
3113 return NULL;
3114 }
3115
3116 // Fancy version which also strips off an offset (and reports it to caller).
3117 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase,
3118 intptr_t& offset) {
3119 Node* base = AddPNode::Ideal_base_and_offset(ptr, phase, offset);
3120 if (base == NULL) return NULL;
3121 return Ideal_allocation(base, phase);
3122 }
3123
3124 // Trace Initialize <- Proj[Parm] <- Allocate
3125 AllocateNode* InitializeNode::allocation() {
3126 Node* rawoop = in(InitializeNode::RawAddress);
3127 if (rawoop->is_Proj()) {
3128 Node* alloc = rawoop->in(0);
3129 if (alloc->is_Allocate()) {
3130 return alloc->as_Allocate();
3131 }
3132 }
3133 return NULL;
3134 }
3135
3136 // Trace Allocate -> Proj[Parm] -> Initialize
3137 InitializeNode* AllocateNode::initialization() {
3138 ProjNode* rawoop = proj_out(AllocateNode::RawAddress);
3139 if (rawoop == NULL) return NULL;
3140 for (DUIterator_Fast imax, i = rawoop->fast_outs(imax); i < imax; i++) {
3141 Node* init = rawoop->fast_out(i);
3142 if (init->is_Initialize()) {
3143 assert(init->as_Initialize()->allocation() == this, "2-way link");
3144 return init->as_Initialize();
3145 }
3146 }
3147 return NULL;
3148 }
3149
3150 //----------------------------- store barriers ----------------------------
3151 #define __ ideal.
3152
3153 void GraphKit::sync_kit(IdealKit& ideal) {
3154 // Final sync IdealKit and graphKit.
3155 __ drain_delay_transform();
3156 set_all_memory(__ merged_memory());
3157 set_control(__ ctrl());
3158 }
3159
3160 // vanilla/CMS post barrier
3161 // Insert a write-barrier store. This is to let generational GC work; we have
3162 // to flag all oop-stores before the next GC point.
3163 void GraphKit::write_barrier_post(Node* oop_store,
3164 Node* obj,
3165 Node* adr,
3166 Node* val,
3167 bool use_precise) {
3168 // No store check needed if we're storing a NULL or an old object
3169 // (latter case is probably a string constant). The concurrent
3170 // mark sweep garbage collector, however, needs to have all nonNull
3171 // oop updates flagged via card-marks.
3172 if (val != NULL && val->is_Con()) {
3173 // must be either an oop or NULL
3174 const Type* t = val->bottom_type();
3175 if (t == TypePtr::NULL_PTR || t == Type::TOP)
3176 // stores of null never (?) need barriers
3177 return;
3178 ciObject* con = t->is_oopptr()->const_oop();
3179 if (con != NULL
3180 && con->is_perm()
3181 && Universe::heap()->can_elide_permanent_oop_store_barriers())
3182 // no store barrier needed, because no old-to-new ref created
3183 return;
3184 }
3185
3186 if (!use_precise) {
3187 // All card marks for a (non-array) instance are in one place:
3188 adr = obj;
3189 }
3190 // (Else it's an array (or unknown), and we want more precise card marks.)
3191 assert(adr != NULL, "");
3192
3193 IdealKit ideal(gvn(), control(), merged_memory(), true);
3194
3195 // Convert the pointer to an int prior to doing math on it
3196 Node* cast = __ CastPX(__ ctrl(), adr);
3197
3198 // Divide by card size
3199 assert(Universe::heap()->barrier_set()->kind() == BarrierSet::CardTableModRef,
3200 "Only one we handle so far.");
3201 Node* card_offset = __ URShiftX( cast, __ ConI(CardTableModRefBS::card_shift) );
3202
3203 // Combine card table base and card offset
3204 Node* card_adr = __ AddP(__ top(), byte_map_base_node(), card_offset );
3205
3206 // Get the alias_index for raw card-mark memory
3207 int adr_type = Compile::AliasIdxRaw;
3208 // Smash zero into card
3209 Node* zero = __ ConI(0);
3210 BasicType bt = T_BYTE;
3211 if( !UseConcMarkSweepGC ) {
3212 __ store(__ ctrl(), card_adr, zero, bt, adr_type);
3213 } else {
3214 // Specialized path for CM store barrier
3215 __ storeCM(__ ctrl(), card_adr, zero, oop_store, bt, adr_type);
3216 }
3217
3218 // Final sync IdealKit and GraphKit.
3219 sync_kit(ideal);
3220 }
3221
3222 // G1 pre/post barriers
3223 void GraphKit::g1_write_barrier_pre(Node* obj,
3224 Node* adr,
3225 uint alias_idx,
3226 Node* val,
3227 const TypeOopPtr* val_type,
3228 BasicType bt) {
3229 IdealKit ideal(gvn(), control(), merged_memory(), true);
3230
3231 Node* tls = __ thread(); // ThreadLocalStorage
3232
3233 Node* no_ctrl = NULL;
3234 Node* no_base = __ top();
3235 Node* zero = __ ConI(0);
3236
3237 float likely = PROB_LIKELY(0.999);
3238 float unlikely = PROB_UNLIKELY(0.999);
3239
3240 BasicType active_type = in_bytes(PtrQueue::byte_width_of_active()) == 4 ? T_INT : T_BYTE;
3241 assert(in_bytes(PtrQueue::byte_width_of_active()) == 4 || in_bytes(PtrQueue::byte_width_of_active()) == 1, "flag width");
3242
3243 // Offsets into the thread
3244 const int marking_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 648
3245 PtrQueue::byte_offset_of_active());
3246 const int index_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 656
3247 PtrQueue::byte_offset_of_index());
3248 const int buffer_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 652
3249 PtrQueue::byte_offset_of_buf());
3250 // Now the actual pointers into the thread
3251
3252 // set_control( ctl);
3253
3254 Node* marking_adr = __ AddP(no_base, tls, __ ConX(marking_offset));
3255 Node* buffer_adr = __ AddP(no_base, tls, __ ConX(buffer_offset));
3256 Node* index_adr = __ AddP(no_base, tls, __ ConX(index_offset));
3257
3258 // Now some of the values
3259
3260 Node* marking = __ load(__ ctrl(), marking_adr, TypeInt::INT, active_type, Compile::AliasIdxRaw);
3261
3262 // if (!marking)
3263 __ if_then(marking, BoolTest::ne, zero); {
3264 Node* index = __ load(__ ctrl(), index_adr, TypeInt::INT, T_INT, Compile::AliasIdxRaw);
3265
3266 const Type* t1 = adr->bottom_type();
3267 const Type* t2 = val->bottom_type();
3268
3269 Node* orig = __ load(no_ctrl, adr, val_type, bt, alias_idx);
3270 // if (orig != NULL)
3271 __ if_then(orig, BoolTest::ne, null()); {
3272 Node* buffer = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw);
3273
3274 // load original value
3275 // alias_idx correct??
3276
3277 // is the queue for this thread full?
3278 __ if_then(index, BoolTest::ne, zero, likely); {
3279
3280 // decrement the index
3281 Node* next_index = __ SubI(index, __ ConI(sizeof(intptr_t)));
3282 Node* next_indexX = next_index;
3283 #ifdef _LP64
3284 // We could refine the type for what it's worth
3285 // const TypeLong* lidxtype = TypeLong::make(CONST64(0), get_size_from_queue);
3286 next_indexX = _gvn.transform( new (C, 2) ConvI2LNode(next_index, TypeLong::make(0, max_jlong, Type::WidenMax)) );
3287 #endif
3288
3289 // Now get the buffer location we will log the original value into and store it
3290 Node *log_addr = __ AddP(no_base, buffer, next_indexX);
3291 __ store(__ ctrl(), log_addr, orig, T_OBJECT, Compile::AliasIdxRaw);
3292
3293 // update the index
3294 __ store(__ ctrl(), index_adr, next_index, T_INT, Compile::AliasIdxRaw);
3295
3296 } __ else_(); {
3297
3298 // logging buffer is full, call the runtime
3299 const TypeFunc *tf = OptoRuntime::g1_wb_pre_Type();
3300 __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_pre), "g1_wb_pre", orig, tls);
3301 } __ end_if(); // (!index)
3302 } __ end_if(); // (orig != NULL)
3303 } __ end_if(); // (!marking)
3304
3305 // Final sync IdealKit and GraphKit.
3306 sync_kit(ideal);
3307 }
3308
3309 //
3310 // Update the card table and add card address to the queue
3311 //
3312 void GraphKit::g1_mark_card(IdealKit& ideal,
3313 Node* card_adr,
3314 Node* oop_store,
3315 Node* index,
3316 Node* index_adr,
3317 Node* buffer,
3318 const TypeFunc* tf) {
3319
3320 Node* zero = __ ConI(0);
3321 Node* no_base = __ top();
3322 BasicType card_bt = T_BYTE;
3323 // Smash zero into card. MUST BE ORDERED WRT TO STORE
3324 __ storeCM(__ ctrl(), card_adr, zero, oop_store, card_bt, Compile::AliasIdxRaw);
3325
3326 // Now do the queue work
3327 __ if_then(index, BoolTest::ne, zero); {
3328
3329 Node* next_index = __ SubI(index, __ ConI(sizeof(intptr_t)));
3330 Node* next_indexX = next_index;
3331 #ifdef _LP64
3332 // We could refine the type for what it's worth
3333 // const TypeLong* lidxtype = TypeLong::make(CONST64(0), get_size_from_queue);
3334 next_indexX = _gvn.transform( new (C, 2) ConvI2LNode(next_index, TypeLong::make(0, max_jlong, Type::WidenMax)) );
3335 #endif // _LP64
3336 Node* log_addr = __ AddP(no_base, buffer, next_indexX);
3337
3338 __ store(__ ctrl(), log_addr, card_adr, T_ADDRESS, Compile::AliasIdxRaw);
3339 __ store(__ ctrl(), index_adr, next_index, T_INT, Compile::AliasIdxRaw);
3340
3341 } __ else_(); {
3342 __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_post), "g1_wb_post", card_adr, __ thread());
3343 } __ end_if();
3344
3345 }
3346
3347 void GraphKit::g1_write_barrier_post(Node* oop_store,
3348 Node* obj,
3349 Node* adr,
3350 uint alias_idx,
3351 Node* val,
3352 BasicType bt,
3353 bool use_precise) {
3354 // If we are writing a NULL then we need no post barrier
3355
3356 if (val != NULL && val->is_Con() && val->bottom_type() == TypePtr::NULL_PTR) {
3357 // Must be NULL
3358 const Type* t = val->bottom_type();
3359 assert(t == Type::TOP || t == TypePtr::NULL_PTR, "must be NULL");
3360 // No post barrier if writing NULLx
3361 return;
3362 }
3363
3364 if (!use_precise) {
3365 // All card marks for a (non-array) instance are in one place:
3366 adr = obj;
3367 }
3368 // (Else it's an array (or unknown), and we want more precise card marks.)
3369 assert(adr != NULL, "");
3370
3371 IdealKit ideal(gvn(), control(), merged_memory(), true);
3372
3373 Node* tls = __ thread(); // ThreadLocalStorage
3374
3375 Node* no_ctrl = NULL;
3376 Node* no_base = __ top();
3377 float likely = PROB_LIKELY(0.999);
3378 float unlikely = PROB_UNLIKELY(0.999);
3379 Node* zero = __ ConI(0);
3380 Node* zeroX = __ ConX(0);
3381
3382 // Get the alias_index for raw card-mark memory
3383 const TypePtr* card_type = TypeRawPtr::BOTTOM;
3384
3385 const TypeFunc *tf = OptoRuntime::g1_wb_post_Type();
3386
3387 // Offsets into the thread
3388 const int index_offset = in_bytes(JavaThread::dirty_card_queue_offset() +
3389 PtrQueue::byte_offset_of_index());
3390 const int buffer_offset = in_bytes(JavaThread::dirty_card_queue_offset() +
3391 PtrQueue::byte_offset_of_buf());
3392
3393 // Pointers into the thread
3394
3395 Node* buffer_adr = __ AddP(no_base, tls, __ ConX(buffer_offset));
3396 Node* index_adr = __ AddP(no_base, tls, __ ConX(index_offset));
3397
3398 // Now some values
3399
3400 Node* index = __ load(no_ctrl, index_adr, TypeInt::INT, T_INT, Compile::AliasIdxRaw);
3401 Node* buffer = __ load(no_ctrl, buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw);
3402
3403
3404 // Convert the store obj pointer to an int prior to doing math on it
3405 // Must use ctrl to prevent "integerized oop" existing across safepoint
3406 Node* cast = __ CastPX(__ ctrl(), adr);
3407
3408 // Divide pointer by card size
3409 Node* card_offset = __ URShiftX( cast, __ ConI(CardTableModRefBS::card_shift) );
3410
3411 // Combine card table base and card offset
3412 Node* card_adr = __ AddP(no_base, byte_map_base_node(), card_offset );
3413
3414 // If we know the value being stored does it cross regions?
3415
3416 if (val != NULL) {
3417 // Does the store cause us to cross regions?
3418
3419 // Should be able to do an unsigned compare of region_size instead of
3420 // and extra shift. Do we have an unsigned compare??
3421 // Node* region_size = __ ConI(1 << HeapRegion::LogOfHRGrainBytes);
3422 Node* xor_res = __ URShiftX ( __ XorX( cast, __ CastPX(__ ctrl(), val)), __ ConI(HeapRegion::LogOfHRGrainBytes));
3423
3424 // if (xor_res == 0) same region so skip
3425 __ if_then(xor_res, BoolTest::ne, zeroX); {
3426
3427 // No barrier if we are storing a NULL
3428 __ if_then(val, BoolTest::ne, null(), unlikely); {
3429
3430 // Ok must mark the card if not already dirty
3431
3432 // load the original value of the card
3433 Node* card_val = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw);
3434
3435 __ if_then(card_val, BoolTest::ne, zero); {
3436 g1_mark_card(ideal, card_adr, oop_store, index, index_adr, buffer, tf);
3437 } __ end_if();
3438 } __ end_if();
3439 } __ end_if();
3440 } else {
3441 // Object.clone() instrinsic uses this path.
3442 g1_mark_card(ideal, card_adr, oop_store, index, index_adr, buffer, tf);
3443 }
3444
3445 // Final sync IdealKit and GraphKit.
3446 sync_kit(ideal);
3447 }
3448 #undef __
3449