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 if (CheckExceptionEventsNeeded) {
464 // if the exception capability is set, then we will generate a
465 // runtime call to see if we actually need to report exception
466 // events. If we don't need to report exception events, we will
467 // take the normal fast path provided by add_exception_events.
468 // If exception event reporting is enabled, we will take the
469 // uncommon_trap in the BuildCutout below.
470
471 // call C++ runtime routine to determine whether we need to
472 // report exception events
473 Node* c = make_runtime_call(RC_LEAF, OptoRuntime::must_post_exception_events_Type(),
474 CAST_FROM_FN_PTR(address, JvmtiExport::must_post_exception_events_jrt_leaf),
475 "must_post_exception_events", NULL //no memory effects
476 );
477
478 Node* need_exc_bool = _gvn.transform(new (C, 1) ProjNode(c, TypeFunc::Parms + 0));
479
480 // Test the result returned by the runtime call vs. 0
481 Node* zero = _gvn.intcon(0);
482 Node* chk = _gvn.transform( new (C, 3) CmpINode(need_exc_bool, zero) );
483 BoolTest::mask btesteq = BoolTest::eq;
484 Node* tst = _gvn.transform( new (C, 2) BoolNode(chk, btesteq) );
485
486 // Branch to slow_path if runtime call returned true
487 { BuildCutout unless(this, tst, PROB_MAX);
488 // Do not try anything fancy if we're notifying the VM on every throw.
489 // Cf. case Bytecodes::_athrow in parse2.cpp.
490 uncommon_trap(reason, Deoptimization::Action_none,
491 (ciKlass*)NULL, (char*)NULL, must_throw);
492 }
493 // here if the runtime call returned false
494 // note we do not return here, but continue on with the normal codegen
495 }
496 else {
497 // CheckExceptionEventsNeeded is false
498 // Do not try anything fancy if we're notifying the VM on every throw.
499 // Cf. case Bytecodes::_athrow in parse2.cpp.
500 uncommon_trap(reason, Deoptimization::Action_none,
501 (ciKlass*)NULL, (char*)NULL, must_throw);
502 return;
503 }
504 }
505
506 // If this particular condition has not yet happened at this
507 // bytecode, then use the uncommon trap mechanism, and allow for
508 // a future recompilation if several traps occur here.
509 // If the throw is hot, try to use a more complicated inline mechanism
510 // which keeps execution inside the compiled code.
511 bool treat_throw_as_hot = false;
512 ciMethodData* md = method()->method_data();
513
514 if (ProfileTraps) {
515 if (too_many_traps(reason)) {
516 treat_throw_as_hot = true;
517 }
518 // (If there is no MDO at all, assume it is early in
519 // execution, and that any deopts are part of the
520 // startup transient, and don't need to be remembered.)
521
522 // Also, if there is a local exception handler, treat all throws
523 // as hot if there has been at least one in this method.
524 if (C->trap_count(reason) != 0
525 && method()->method_data()->trap_count(reason) != 0
526 && has_ex_handler()) {
527 treat_throw_as_hot = true;
528 }
529 }
530
531 // If this throw happens frequently, an uncommon trap might cause
532 // a performance pothole. If there is a local exception handler,
533 // and if this particular bytecode appears to be deoptimizing often,
534 // let us handle the throw inline, with a preconstructed instance.
535 // Note: If the deopt count has blown up, the uncommon trap
536 // runtime is going to flush this nmethod, not matter what.
537 if (treat_throw_as_hot
538 && (!StackTraceInThrowable || OmitStackTraceInFastThrow)) {
539 // If the throw is local, we use a pre-existing instance and
540 // punt on the backtrace. This would lead to a missing backtrace
541 // (a repeat of 4292742) if the backtrace object is ever asked
542 // for its backtrace.
543 // Fixing this remaining case of 4292742 requires some flavor of
544 // escape analysis. Leave that for the future.
545 ciInstance* ex_obj = NULL;
546 switch (reason) {
547 case Deoptimization::Reason_null_check:
548 ex_obj = env()->NullPointerException_instance();
549 break;
550 case Deoptimization::Reason_div0_check:
551 ex_obj = env()->ArithmeticException_instance();
552 break;
553 case Deoptimization::Reason_range_check:
554 ex_obj = env()->ArrayIndexOutOfBoundsException_instance();
555 break;
556 case Deoptimization::Reason_class_check:
557 if (java_bc() == Bytecodes::_aastore) {
558 ex_obj = env()->ArrayStoreException_instance();
559 } else {
560 ex_obj = env()->ClassCastException_instance();
561 }
562 break;
563 }
564 if (failing()) { stop(); return; } // exception allocation might fail
565 if (ex_obj != NULL) {
566 // Cheat with a preallocated exception object.
567 if (C->log() != NULL)
568 C->log()->elem("hot_throw preallocated='1' reason='%s'",
569 Deoptimization::trap_reason_name(reason));
570 const TypeInstPtr* ex_con = TypeInstPtr::make(ex_obj);
571 Node* ex_node = _gvn.transform( ConNode::make(C, ex_con) );
572
573 // Clear the detail message of the preallocated exception object.
574 // Weblogic sometimes mutates the detail message of exceptions
575 // using reflection.
576 int offset = java_lang_Throwable::get_detailMessage_offset();
577 const TypePtr* adr_typ = ex_con->add_offset(offset);
578
579 Node *adr = basic_plus_adr(ex_node, ex_node, offset);
580 Node *store = store_oop_to_object(control(), ex_node, adr, adr_typ, null(), ex_con, T_OBJECT);
581
582 add_exception_state(make_exception_state(ex_node));
583 return;
584 }
585 }
586
587 // %%% Maybe add entry to OptoRuntime which directly throws the exc.?
588 // It won't be much cheaper than bailing to the interp., since we'll
589 // have to pass up all the debug-info, and the runtime will have to
590 // create the stack trace.
591
592 // Usual case: Bail to interpreter.
593 // Reserve the right to recompile if we haven't seen anything yet.
594
595 Deoptimization::DeoptAction action = Deoptimization::Action_maybe_recompile;
596 if (treat_throw_as_hot
597 && (method()->method_data()->trap_recompiled_at(bci())
598 || C->too_many_traps(reason))) {
599 // We cannot afford to take more traps here. Suffer in the interpreter.
600 if (C->log() != NULL)
601 C->log()->elem("hot_throw preallocated='0' reason='%s' mcount='%d'",
602 Deoptimization::trap_reason_name(reason),
603 C->trap_count(reason));
604 action = Deoptimization::Action_none;
605 }
606
607 // "must_throw" prunes the JVM state to include only the stack, if there
608 // are no local exception handlers. This should cut down on register
609 // allocation time and code size, by drastically reducing the number
610 // of in-edges on the call to the uncommon trap.
611
612 uncommon_trap(reason, action, (ciKlass*)NULL, (char*)NULL, must_throw);
613 }
614
615
616 //----------------------------PreserveJVMState---------------------------------
617 PreserveJVMState::PreserveJVMState(GraphKit* kit, bool clone_map) {
618 debug_only(kit->verify_map());
619 _kit = kit;
620 _map = kit->map(); // preserve the map
621 _sp = kit->sp();
622 kit->set_map(clone_map ? kit->clone_map() : NULL);
623 #ifdef ASSERT
624 _bci = kit->bci();
625 Parse* parser = kit->is_Parse();
626 int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo();
627 _block = block;
628 #endif
629 }
630 PreserveJVMState::~PreserveJVMState() {
631 GraphKit* kit = _kit;
632 #ifdef ASSERT
633 assert(kit->bci() == _bci, "bci must not shift");
634 Parse* parser = kit->is_Parse();
635 int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo();
636 assert(block == _block, "block must not shift");
637 #endif
638 kit->set_map(_map);
639 kit->set_sp(_sp);
640 }
641
642
643 //-----------------------------BuildCutout-------------------------------------
644 BuildCutout::BuildCutout(GraphKit* kit, Node* p, float prob, float cnt)
645 : PreserveJVMState(kit)
646 {
647 assert(p->is_Con() || p->is_Bool(), "test must be a bool");
648 SafePointNode* outer_map = _map; // preserved map is caller's
649 SafePointNode* inner_map = kit->map();
650 IfNode* iff = kit->create_and_map_if(outer_map->control(), p, prob, cnt);
651 outer_map->set_control(kit->gvn().transform( new (kit->C, 1) IfTrueNode(iff) ));
652 inner_map->set_control(kit->gvn().transform( new (kit->C, 1) IfFalseNode(iff) ));
653 }
654 BuildCutout::~BuildCutout() {
655 GraphKit* kit = _kit;
656 assert(kit->stopped(), "cutout code must stop, throw, return, etc.");
657 }
658
659 //---------------------------PreserveReexecuteState----------------------------
660 PreserveReexecuteState::PreserveReexecuteState(GraphKit* kit) {
661 assert(!kit->stopped(), "must call stopped() before");
662 _kit = kit;
663 _sp = kit->sp();
664 _reexecute = kit->jvms()->_reexecute;
665 }
666 PreserveReexecuteState::~PreserveReexecuteState() {
667 if (_kit->stopped()) return;
668 _kit->jvms()->_reexecute = _reexecute;
669 _kit->set_sp(_sp);
670 }
671
672 //------------------------------clone_map--------------------------------------
673 // Implementation of PreserveJVMState
674 //
675 // Only clone_map(...) here. If this function is only used in the
676 // PreserveJVMState class we may want to get rid of this extra
677 // function eventually and do it all there.
678
679 SafePointNode* GraphKit::clone_map() {
680 if (map() == NULL) return NULL;
681
682 // Clone the memory edge first
683 Node* mem = MergeMemNode::make(C, map()->memory());
684 gvn().set_type_bottom(mem);
685
686 SafePointNode *clonemap = (SafePointNode*)map()->clone();
687 JVMState* jvms = this->jvms();
688 JVMState* clonejvms = jvms->clone_shallow(C);
689 clonemap->set_memory(mem);
690 clonemap->set_jvms(clonejvms);
691 clonejvms->set_map(clonemap);
692 record_for_igvn(clonemap);
693 gvn().set_type_bottom(clonemap);
694 return clonemap;
695 }
696
697
698 //-----------------------------set_map_clone-----------------------------------
699 void GraphKit::set_map_clone(SafePointNode* m) {
700 _map = m;
701 _map = clone_map();
702 _map->set_next_exception(NULL);
703 debug_only(verify_map());
704 }
705
706
707 //----------------------------kill_dead_locals---------------------------------
708 // Detect any locals which are known to be dead, and force them to top.
709 void GraphKit::kill_dead_locals() {
710 // Consult the liveness information for the locals. If any
711 // of them are unused, then they can be replaced by top(). This
712 // should help register allocation time and cut down on the size
713 // of the deoptimization information.
714
715 // This call is made from many of the bytecode handling
716 // subroutines called from the Big Switch in do_one_bytecode.
717 // Every bytecode which might include a slow path is responsible
718 // for killing its dead locals. The more consistent we
719 // are about killing deads, the fewer useless phis will be
720 // constructed for them at various merge points.
721
722 // bci can be -1 (InvocationEntryBci). We return the entry
723 // liveness for the method.
724
725 if (method() == NULL || method()->code_size() == 0) {
726 // We are building a graph for a call to a native method.
727 // All locals are live.
728 return;
729 }
730
731 ResourceMark rm;
732
733 // Consult the liveness information for the locals. If any
734 // of them are unused, then they can be replaced by top(). This
735 // should help register allocation time and cut down on the size
736 // of the deoptimization information.
737 MethodLivenessResult live_locals = method()->liveness_at_bci(bci());
738
739 int len = (int)live_locals.size();
740 assert(len <= jvms()->loc_size(), "too many live locals");
741 for (int local = 0; local < len; local++) {
742 if (!live_locals.at(local)) {
743 set_local(local, top());
744 }
745 }
746 }
747
748 #ifdef ASSERT
749 //-------------------------dead_locals_are_killed------------------------------
750 // Return true if all dead locals are set to top in the map.
751 // Used to assert "clean" debug info at various points.
752 bool GraphKit::dead_locals_are_killed() {
753 if (method() == NULL || method()->code_size() == 0) {
754 // No locals need to be dead, so all is as it should be.
755 return true;
756 }
757
758 // Make sure somebody called kill_dead_locals upstream.
759 ResourceMark rm;
760 for (JVMState* jvms = this->jvms(); jvms != NULL; jvms = jvms->caller()) {
761 if (jvms->loc_size() == 0) continue; // no locals to consult
762 SafePointNode* map = jvms->map();
763 ciMethod* method = jvms->method();
764 int bci = jvms->bci();
765 if (jvms == this->jvms()) {
766 bci = this->bci(); // it might not yet be synched
767 }
768 MethodLivenessResult live_locals = method->liveness_at_bci(bci);
769 int len = (int)live_locals.size();
770 if (!live_locals.is_valid() || len == 0)
771 // This method is trivial, or is poisoned by a breakpoint.
772 return true;
773 assert(len == jvms->loc_size(), "live map consistent with locals map");
774 for (int local = 0; local < len; local++) {
775 if (!live_locals.at(local) && map->local(jvms, local) != top()) {
776 if (PrintMiscellaneous && (Verbose || WizardMode)) {
777 tty->print_cr("Zombie local %d: ", local);
778 jvms->dump();
779 }
780 return false;
781 }
782 }
783 }
784 return true;
785 }
786
787 #endif //ASSERT
788
789 // Helper function for enforcing certain bytecodes to reexecute if
790 // deoptimization happens
791 static bool should_reexecute_implied_by_bytecode(JVMState *jvms) {
792 ciMethod* cur_method = jvms->method();
793 int cur_bci = jvms->bci();
794 if (cur_method != NULL && cur_bci != InvocationEntryBci) {
795 Bytecodes::Code code = cur_method->java_code_at_bci(cur_bci);
796 return Interpreter::bytecode_should_reexecute(code);
797 } else
798 return false;
799 }
800
801 // Helper function for adding JVMState and debug information to node
802 void GraphKit::add_safepoint_edges(SafePointNode* call, bool must_throw) {
803 // Add the safepoint edges to the call (or other safepoint).
804
805 // Make sure dead locals are set to top. This
806 // should help register allocation time and cut down on the size
807 // of the deoptimization information.
808 assert(dead_locals_are_killed(), "garbage in debug info before safepoint");
809
810 // Walk the inline list to fill in the correct set of JVMState's
811 // Also fill in the associated edges for each JVMState.
812
813 JVMState* youngest_jvms = sync_jvms();
814
815 // Do we need debug info here? If it is a SafePoint and this method
816 // cannot de-opt, then we do NOT need any debug info.
817 bool full_info = (C->deopt_happens() || call->Opcode() != Op_SafePoint);
818
819 // If we are guaranteed to throw, we can prune everything but the
820 // input to the current bytecode.
821 bool can_prune_locals = false;
822 uint stack_slots_not_pruned = 0;
823 int inputs = 0, depth = 0;
824 if (must_throw) {
825 assert(method() == youngest_jvms->method(), "sanity");
826 if (compute_stack_effects(inputs, depth)) {
827 can_prune_locals = true;
828 stack_slots_not_pruned = inputs;
829 }
830 }
831
832 if (env()->jvmti_can_examine_or_deopt_anywhere()) {
833 // At any safepoint, this method can get breakpointed, which would
834 // then require an immediate deoptimization.
835 full_info = true;
836 can_prune_locals = false; // do not prune locals
837 stack_slots_not_pruned = 0;
838 }
839
840 // do not scribble on the input jvms
841 JVMState* out_jvms = youngest_jvms->clone_deep(C);
842 call->set_jvms(out_jvms); // Start jvms list for call node
843
844 // For a known set of bytecodes, the interpreter should reexecute them if
845 // deoptimization happens. We set the reexecute state for them here
846 if (out_jvms->is_reexecute_undefined() && //don't change if already specified
847 should_reexecute_implied_by_bytecode(out_jvms)) {
848 out_jvms->set_should_reexecute(true); //NOTE: youngest_jvms not changed
849 }
850
851 // Presize the call:
852 debug_only(uint non_debug_edges = call->req());
853 call->add_req_batch(top(), youngest_jvms->debug_depth());
854 assert(call->req() == non_debug_edges + youngest_jvms->debug_depth(), "");
855
856 // Set up edges so that the call looks like this:
857 // Call [state:] ctl io mem fptr retadr
858 // [parms:] parm0 ... parmN
859 // [root:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
860 // [...mid:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN [...]
861 // [young:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
862 // Note that caller debug info precedes callee debug info.
863
864 // Fill pointer walks backwards from "young:" to "root:" in the diagram above:
865 uint debug_ptr = call->req();
866
867 // Loop over the map input edges associated with jvms, add them
868 // to the call node, & reset all offsets to match call node array.
869 for (JVMState* in_jvms = youngest_jvms; in_jvms != NULL; ) {
870 uint debug_end = debug_ptr;
871 uint debug_start = debug_ptr - in_jvms->debug_size();
872 debug_ptr = debug_start; // back up the ptr
873
874 uint p = debug_start; // walks forward in [debug_start, debug_end)
875 uint j, k, l;
876 SafePointNode* in_map = in_jvms->map();
877 out_jvms->set_map(call);
878
879 if (can_prune_locals) {
880 assert(in_jvms->method() == out_jvms->method(), "sanity");
881 // If the current throw can reach an exception handler in this JVMS,
882 // then we must keep everything live that can reach that handler.
883 // As a quick and dirty approximation, we look for any handlers at all.
884 if (in_jvms->method()->has_exception_handlers()) {
885 can_prune_locals = false;
886 }
887 }
888
889 // Add the Locals
890 k = in_jvms->locoff();
891 l = in_jvms->loc_size();
892 out_jvms->set_locoff(p);
893 if (full_info && !can_prune_locals) {
894 for (j = 0; j < l; j++)
895 call->set_req(p++, in_map->in(k+j));
896 } else {
897 p += l; // already set to top above by add_req_batch
898 }
899
900 // Add the Expression Stack
901 k = in_jvms->stkoff();
902 l = in_jvms->sp();
903 out_jvms->set_stkoff(p);
904 if (full_info && !can_prune_locals) {
905 for (j = 0; j < l; j++)
906 call->set_req(p++, in_map->in(k+j));
907 } else if (can_prune_locals && stack_slots_not_pruned != 0) {
908 // Divide stack into {S0,...,S1}, where S0 is set to top.
909 uint s1 = stack_slots_not_pruned;
910 stack_slots_not_pruned = 0; // for next iteration
911 if (s1 > l) s1 = l;
912 uint s0 = l - s1;
913 p += s0; // skip the tops preinstalled by add_req_batch
914 for (j = s0; j < l; j++)
915 call->set_req(p++, in_map->in(k+j));
916 } else {
917 p += l; // already set to top above by add_req_batch
918 }
919
920 // Add the Monitors
921 k = in_jvms->monoff();
922 l = in_jvms->mon_size();
923 out_jvms->set_monoff(p);
924 for (j = 0; j < l; j++)
925 call->set_req(p++, in_map->in(k+j));
926
927 // Copy any scalar object fields.
928 k = in_jvms->scloff();
929 l = in_jvms->scl_size();
930 out_jvms->set_scloff(p);
931 for (j = 0; j < l; j++)
932 call->set_req(p++, in_map->in(k+j));
933
934 // Finish the new jvms.
935 out_jvms->set_endoff(p);
936
937 assert(out_jvms->endoff() == debug_end, "fill ptr must match");
938 assert(out_jvms->depth() == in_jvms->depth(), "depth must match");
939 assert(out_jvms->loc_size() == in_jvms->loc_size(), "size must match");
940 assert(out_jvms->mon_size() == in_jvms->mon_size(), "size must match");
941 assert(out_jvms->scl_size() == in_jvms->scl_size(), "size must match");
942 assert(out_jvms->debug_size() == in_jvms->debug_size(), "size must match");
943
944 // Update the two tail pointers in parallel.
945 out_jvms = out_jvms->caller();
946 in_jvms = in_jvms->caller();
947 }
948
949 assert(debug_ptr == non_debug_edges, "debug info must fit exactly");
950
951 // Test the correctness of JVMState::debug_xxx accessors:
952 assert(call->jvms()->debug_start() == non_debug_edges, "");
953 assert(call->jvms()->debug_end() == call->req(), "");
954 assert(call->jvms()->debug_depth() == call->req() - non_debug_edges, "");
955 }
956
957 bool GraphKit::compute_stack_effects(int& inputs, int& depth) {
958 Bytecodes::Code code = java_bc();
959 if (code == Bytecodes::_wide) {
960 code = method()->java_code_at_bci(bci() + 1);
961 }
962
963 BasicType rtype = T_ILLEGAL;
964 int rsize = 0;
965
966 if (code != Bytecodes::_illegal) {
967 depth = Bytecodes::depth(code); // checkcast=0, athrow=-1
968 rtype = Bytecodes::result_type(code); // checkcast=P, athrow=V
969 if (rtype < T_CONFLICT)
970 rsize = type2size[rtype];
971 }
972
973 switch (code) {
974 case Bytecodes::_illegal:
975 return false;
976
977 case Bytecodes::_ldc:
978 case Bytecodes::_ldc_w:
979 case Bytecodes::_ldc2_w:
980 inputs = 0;
981 break;
982
983 case Bytecodes::_dup: inputs = 1; break;
984 case Bytecodes::_dup_x1: inputs = 2; break;
985 case Bytecodes::_dup_x2: inputs = 3; break;
986 case Bytecodes::_dup2: inputs = 2; break;
987 case Bytecodes::_dup2_x1: inputs = 3; break;
988 case Bytecodes::_dup2_x2: inputs = 4; break;
989 case Bytecodes::_swap: inputs = 2; break;
990 case Bytecodes::_arraylength: inputs = 1; break;
991
992 case Bytecodes::_getstatic:
993 case Bytecodes::_putstatic:
994 case Bytecodes::_getfield:
995 case Bytecodes::_putfield:
996 {
997 bool is_get = (depth >= 0), is_static = (depth & 1);
998 bool ignore;
999 ciBytecodeStream iter(method());
1000 iter.reset_to_bci(bci());
1001 iter.next();
1002 ciField* field = iter.get_field(ignore);
1003 int size = field->type()->size();
1004 inputs = (is_static ? 0 : 1);
1005 if (is_get) {
1006 depth = size - inputs;
1007 } else {
1008 inputs += size; // putxxx pops the value from the stack
1009 depth = - inputs;
1010 }
1011 }
1012 break;
1013
1014 case Bytecodes::_invokevirtual:
1015 case Bytecodes::_invokespecial:
1016 case Bytecodes::_invokestatic:
1017 case Bytecodes::_invokedynamic:
1018 case Bytecodes::_invokeinterface:
1019 {
1020 bool is_static = (depth == 0);
1021 bool ignore;
1022 ciBytecodeStream iter(method());
1023 iter.reset_to_bci(bci());
1024 iter.next();
1025 ciMethod* method = iter.get_method(ignore);
1026 inputs = method->arg_size_no_receiver();
1027 if (!is_static) inputs += 1;
1028 int size = method->return_type()->size();
1029 depth = size - inputs;
1030 }
1031 break;
1032
1033 case Bytecodes::_multianewarray:
1034 {
1035 ciBytecodeStream iter(method());
1036 iter.reset_to_bci(bci());
1037 iter.next();
1038 inputs = iter.get_dimensions();
1039 assert(rsize == 1, "");
1040 depth = rsize - inputs;
1041 }
1042 break;
1043
1044 case Bytecodes::_ireturn:
1045 case Bytecodes::_lreturn:
1046 case Bytecodes::_freturn:
1047 case Bytecodes::_dreturn:
1048 case Bytecodes::_areturn:
1049 assert(rsize = -depth, "");
1050 inputs = rsize;
1051 break;
1052
1053 case Bytecodes::_jsr:
1054 case Bytecodes::_jsr_w:
1055 inputs = 0;
1056 depth = 1; // S.B. depth=1, not zero
1057 break;
1058
1059 default:
1060 // bytecode produces a typed result
1061 inputs = rsize - depth;
1062 assert(inputs >= 0, "");
1063 break;
1064 }
1065
1066 #ifdef ASSERT
1067 // spot check
1068 int outputs = depth + inputs;
1069 assert(outputs >= 0, "sanity");
1070 switch (code) {
1071 case Bytecodes::_checkcast: assert(inputs == 1 && outputs == 1, ""); break;
1072 case Bytecodes::_athrow: assert(inputs == 1 && outputs == 0, ""); break;
1073 case Bytecodes::_aload_0: assert(inputs == 0 && outputs == 1, ""); break;
1074 case Bytecodes::_return: assert(inputs == 0 && outputs == 0, ""); break;
1075 case Bytecodes::_drem: assert(inputs == 4 && outputs == 2, ""); break;
1076 }
1077 #endif //ASSERT
1078
1079 return true;
1080 }
1081
1082
1083
1084 //------------------------------basic_plus_adr---------------------------------
1085 Node* GraphKit::basic_plus_adr(Node* base, Node* ptr, Node* offset) {
1086 // short-circuit a common case
1087 if (offset == intcon(0)) return ptr;
1088 return _gvn.transform( new (C, 4) AddPNode(base, ptr, offset) );
1089 }
1090
1091 Node* GraphKit::ConvI2L(Node* offset) {
1092 // short-circuit a common case
1093 jint offset_con = find_int_con(offset, Type::OffsetBot);
1094 if (offset_con != Type::OffsetBot) {
1095 return longcon((long) offset_con);
1096 }
1097 return _gvn.transform( new (C, 2) ConvI2LNode(offset));
1098 }
1099 Node* GraphKit::ConvL2I(Node* offset) {
1100 // short-circuit a common case
1101 jlong offset_con = find_long_con(offset, (jlong)Type::OffsetBot);
1102 if (offset_con != (jlong)Type::OffsetBot) {
1103 return intcon((int) offset_con);
1104 }
1105 return _gvn.transform( new (C, 2) ConvL2INode(offset));
1106 }
1107
1108 //-------------------------load_object_klass-----------------------------------
1109 Node* GraphKit::load_object_klass(Node* obj) {
1110 // Special-case a fresh allocation to avoid building nodes:
1111 Node* akls = AllocateNode::Ideal_klass(obj, &_gvn);
1112 if (akls != NULL) return akls;
1113 Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes());
1114 return _gvn.transform( LoadKlassNode::make(_gvn, immutable_memory(), k_adr, TypeInstPtr::KLASS) );
1115 }
1116
1117 //-------------------------load_array_length-----------------------------------
1118 Node* GraphKit::load_array_length(Node* array) {
1119 // Special-case a fresh allocation to avoid building nodes:
1120 AllocateArrayNode* alloc = AllocateArrayNode::Ideal_array_allocation(array, &_gvn);
1121 Node *alen;
1122 if (alloc == NULL) {
1123 Node *r_adr = basic_plus_adr(array, arrayOopDesc::length_offset_in_bytes());
1124 alen = _gvn.transform( new (C, 3) LoadRangeNode(0, immutable_memory(), r_adr, TypeInt::POS));
1125 } else {
1126 alen = alloc->Ideal_length();
1127 Node* ccast = alloc->make_ideal_length(_gvn.type(array)->is_oopptr(), &_gvn);
1128 if (ccast != alen) {
1129 alen = _gvn.transform(ccast);
1130 }
1131 }
1132 return alen;
1133 }
1134
1135 //------------------------------do_null_check----------------------------------
1136 // Helper function to do a NULL pointer check. Returned value is
1137 // the incoming address with NULL casted away. You are allowed to use the
1138 // not-null value only if you are control dependent on the test.
1139 extern int explicit_null_checks_inserted,
1140 explicit_null_checks_elided;
1141 Node* GraphKit::null_check_common(Node* value, BasicType type,
1142 // optional arguments for variations:
1143 bool assert_null,
1144 Node* *null_control) {
1145 assert(!assert_null || null_control == NULL, "not both at once");
1146 if (stopped()) return top();
1147 if (!GenerateCompilerNullChecks && !assert_null && null_control == NULL) {
1148 // For some performance testing, we may wish to suppress null checking.
1149 value = cast_not_null(value); // Make it appear to be non-null (4962416).
1150 return value;
1151 }
1152 explicit_null_checks_inserted++;
1153
1154 // Construct NULL check
1155 Node *chk = NULL;
1156 switch(type) {
1157 case T_LONG : chk = new (C, 3) CmpLNode(value, _gvn.zerocon(T_LONG)); break;
1158 case T_INT : chk = new (C, 3) CmpINode( value, _gvn.intcon(0)); break;
1159 case T_ARRAY : // fall through
1160 type = T_OBJECT; // simplify further tests
1161 case T_OBJECT : {
1162 const Type *t = _gvn.type( value );
1163
1164 const TypeOopPtr* tp = t->isa_oopptr();
1165 if (tp != NULL && tp->klass() != NULL && !tp->klass()->is_loaded()
1166 // Only for do_null_check, not any of its siblings:
1167 && !assert_null && null_control == NULL) {
1168 // Usually, any field access or invocation on an unloaded oop type
1169 // will simply fail to link, since the statically linked class is
1170 // likely also to be unloaded. However, in -Xcomp mode, sometimes
1171 // the static class is loaded but the sharper oop type is not.
1172 // Rather than checking for this obscure case in lots of places,
1173 // we simply observe that a null check on an unloaded class
1174 // will always be followed by a nonsense operation, so we
1175 // can just issue the uncommon trap here.
1176 // Our access to the unloaded class will only be correct
1177 // after it has been loaded and initialized, which requires
1178 // a trip through the interpreter.
1179 #ifndef PRODUCT
1180 if (WizardMode) { tty->print("Null check of unloaded "); tp->klass()->print(); tty->cr(); }
1181 #endif
1182 uncommon_trap(Deoptimization::Reason_unloaded,
1183 Deoptimization::Action_reinterpret,
1184 tp->klass(), "!loaded");
1185 return top();
1186 }
1187
1188 if (assert_null) {
1189 // See if the type is contained in NULL_PTR.
1190 // If so, then the value is already null.
1191 if (t->higher_equal(TypePtr::NULL_PTR)) {
1192 explicit_null_checks_elided++;
1193 return value; // Elided null assert quickly!
1194 }
1195 } else {
1196 // See if mixing in the NULL pointer changes type.
1197 // If so, then the NULL pointer was not allowed in the original
1198 // type. In other words, "value" was not-null.
1199 if (t->meet(TypePtr::NULL_PTR) != t) {
1200 // same as: if (!TypePtr::NULL_PTR->higher_equal(t)) ...
1201 explicit_null_checks_elided++;
1202 return value; // Elided null check quickly!
1203 }
1204 }
1205 chk = new (C, 3) CmpPNode( value, null() );
1206 break;
1207 }
1208
1209 default : ShouldNotReachHere();
1210 }
1211 assert(chk != NULL, "sanity check");
1212 chk = _gvn.transform(chk);
1213
1214 BoolTest::mask btest = assert_null ? BoolTest::eq : BoolTest::ne;
1215 BoolNode *btst = new (C, 2) BoolNode( chk, btest);
1216 Node *tst = _gvn.transform( btst );
1217
1218 //-----------
1219 // if peephole optimizations occurred, a prior test existed.
1220 // If a prior test existed, maybe it dominates as we can avoid this test.
1221 if (tst != btst && type == T_OBJECT) {
1222 // At this point we want to scan up the CFG to see if we can
1223 // find an identical test (and so avoid this test altogether).
1224 Node *cfg = control();
1225 int depth = 0;
1226 while( depth < 16 ) { // Limit search depth for speed
1227 if( cfg->Opcode() == Op_IfTrue &&
1228 cfg->in(0)->in(1) == tst ) {
1229 // Found prior test. Use "cast_not_null" to construct an identical
1230 // CastPP (and hence hash to) as already exists for the prior test.
1231 // Return that casted value.
1232 if (assert_null) {
1233 replace_in_map(value, null());
1234 return null(); // do not issue the redundant test
1235 }
1236 Node *oldcontrol = control();
1237 set_control(cfg);
1238 Node *res = cast_not_null(value);
1239 set_control(oldcontrol);
1240 explicit_null_checks_elided++;
1241 return res;
1242 }
1243 cfg = IfNode::up_one_dom(cfg, /*linear_only=*/ true);
1244 if (cfg == NULL) break; // Quit at region nodes
1245 depth++;
1246 }
1247 }
1248
1249 //-----------
1250 // Branch to failure if null
1251 float ok_prob = PROB_MAX; // a priori estimate: nulls never happen
1252 Deoptimization::DeoptReason reason;
1253 if (assert_null)
1254 reason = Deoptimization::Reason_null_assert;
1255 else if (type == T_OBJECT)
1256 reason = Deoptimization::Reason_null_check;
1257 else
1258 reason = Deoptimization::Reason_div0_check;
1259
1260 // %%% Since Reason_unhandled is not recorded on a per-bytecode basis,
1261 // ciMethodData::has_trap_at will return a conservative -1 if any
1262 // must-be-null assertion has failed. This could cause performance
1263 // problems for a method after its first do_null_assert failure.
1264 // Consider using 'Reason_class_check' instead?
1265
1266 // To cause an implicit null check, we set the not-null probability
1267 // to the maximum (PROB_MAX). For an explicit check the probability
1268 // is set to a smaller value.
1269 if (null_control != NULL || too_many_traps(reason)) {
1270 // probability is less likely
1271 ok_prob = PROB_LIKELY_MAG(3);
1272 } else if (!assert_null &&
1273 (ImplicitNullCheckThreshold > 0) &&
1274 method() != NULL &&
1275 (method()->method_data()->trap_count(reason)
1276 >= (uint)ImplicitNullCheckThreshold)) {
1277 ok_prob = PROB_LIKELY_MAG(3);
1278 }
1279
1280 if (null_control != NULL) {
1281 IfNode* iff = create_and_map_if(control(), tst, ok_prob, COUNT_UNKNOWN);
1282 Node* null_true = _gvn.transform( new (C, 1) IfFalseNode(iff));
1283 set_control( _gvn.transform( new (C, 1) IfTrueNode(iff)));
1284 if (null_true == top())
1285 explicit_null_checks_elided++;
1286 (*null_control) = null_true;
1287 } else {
1288 BuildCutout unless(this, tst, ok_prob);
1289 // Check for optimizer eliding test at parse time
1290 if (stopped()) {
1291 // Failure not possible; do not bother making uncommon trap.
1292 explicit_null_checks_elided++;
1293 } else if (assert_null) {
1294 uncommon_trap(reason,
1295 Deoptimization::Action_make_not_entrant,
1296 NULL, "assert_null");
1297 } else {
1298 replace_in_map(value, zerocon(type));
1299 builtin_throw(reason);
1300 }
1301 }
1302
1303 // Must throw exception, fall-thru not possible?
1304 if (stopped()) {
1305 return top(); // No result
1306 }
1307
1308 if (assert_null) {
1309 // Cast obj to null on this path.
1310 replace_in_map(value, zerocon(type));
1311 return zerocon(type);
1312 }
1313
1314 // Cast obj to not-null on this path, if there is no null_control.
1315 // (If there is a null_control, a non-null value may come back to haunt us.)
1316 if (type == T_OBJECT) {
1317 Node* cast = cast_not_null(value, false);
1318 if (null_control == NULL || (*null_control) == top())
1319 replace_in_map(value, cast);
1320 value = cast;
1321 }
1322
1323 return value;
1324 }
1325
1326
1327 //------------------------------cast_not_null----------------------------------
1328 // Cast obj to not-null on this path
1329 Node* GraphKit::cast_not_null(Node* obj, bool do_replace_in_map) {
1330 const Type *t = _gvn.type(obj);
1331 const Type *t_not_null = t->join(TypePtr::NOTNULL);
1332 // Object is already not-null?
1333 if( t == t_not_null ) return obj;
1334
1335 Node *cast = new (C, 2) CastPPNode(obj,t_not_null);
1336 cast->init_req(0, control());
1337 cast = _gvn.transform( cast );
1338
1339 // Scan for instances of 'obj' in the current JVM mapping.
1340 // These instances are known to be not-null after the test.
1341 if (do_replace_in_map)
1342 replace_in_map(obj, cast);
1343
1344 return cast; // Return casted value
1345 }
1346
1347
1348 //--------------------------replace_in_map-------------------------------------
1349 void GraphKit::replace_in_map(Node* old, Node* neww) {
1350 this->map()->replace_edge(old, neww);
1351
1352 // Note: This operation potentially replaces any edge
1353 // on the map. This includes locals, stack, and monitors
1354 // of the current (innermost) JVM state.
1355
1356 // We can consider replacing in caller maps.
1357 // The idea would be that an inlined function's null checks
1358 // can be shared with the entire inlining tree.
1359 // The expense of doing this is that the PreserveJVMState class
1360 // would have to preserve caller states too, with a deep copy.
1361 }
1362
1363
1364
1365 //=============================================================================
1366 //--------------------------------memory---------------------------------------
1367 Node* GraphKit::memory(uint alias_idx) {
1368 MergeMemNode* mem = merged_memory();
1369 Node* p = mem->memory_at(alias_idx);
1370 _gvn.set_type(p, Type::MEMORY); // must be mapped
1371 return p;
1372 }
1373
1374 //-----------------------------reset_memory------------------------------------
1375 Node* GraphKit::reset_memory() {
1376 Node* mem = map()->memory();
1377 // do not use this node for any more parsing!
1378 debug_only( map()->set_memory((Node*)NULL) );
1379 return _gvn.transform( mem );
1380 }
1381
1382 //------------------------------set_all_memory---------------------------------
1383 void GraphKit::set_all_memory(Node* newmem) {
1384 Node* mergemem = MergeMemNode::make(C, newmem);
1385 gvn().set_type_bottom(mergemem);
1386 map()->set_memory(mergemem);
1387 }
1388
1389 //------------------------------set_all_memory_call----------------------------
1390 void GraphKit::set_all_memory_call(Node* call, bool separate_io_proj) {
1391 Node* newmem = _gvn.transform( new (C, 1) ProjNode(call, TypeFunc::Memory, separate_io_proj) );
1392 set_all_memory(newmem);
1393 }
1394
1395 //=============================================================================
1396 //
1397 // parser factory methods for MemNodes
1398 //
1399 // These are layered on top of the factory methods in LoadNode and StoreNode,
1400 // and integrate with the parser's memory state and _gvn engine.
1401 //
1402
1403 // factory methods in "int adr_idx"
1404 Node* GraphKit::make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
1405 int adr_idx,
1406 bool require_atomic_access) {
1407 assert(adr_idx != Compile::AliasIdxTop, "use other make_load factory" );
1408 const TypePtr* adr_type = NULL; // debug-mode-only argument
1409 debug_only(adr_type = C->get_adr_type(adr_idx));
1410 Node* mem = memory(adr_idx);
1411 Node* ld;
1412 if (require_atomic_access && bt == T_LONG) {
1413 ld = LoadLNode::make_atomic(C, ctl, mem, adr, adr_type, t);
1414 } else {
1415 ld = LoadNode::make(_gvn, ctl, mem, adr, adr_type, t, bt);
1416 }
1417 return _gvn.transform(ld);
1418 }
1419
1420 Node* GraphKit::store_to_memory(Node* ctl, Node* adr, Node *val, BasicType bt,
1421 int adr_idx,
1422 bool require_atomic_access) {
1423 assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1424 const TypePtr* adr_type = NULL;
1425 debug_only(adr_type = C->get_adr_type(adr_idx));
1426 Node *mem = memory(adr_idx);
1427 Node* st;
1428 if (require_atomic_access && bt == T_LONG) {
1429 st = StoreLNode::make_atomic(C, ctl, mem, adr, adr_type, val);
1430 } else {
1431 st = StoreNode::make(_gvn, ctl, mem, adr, adr_type, val, bt);
1432 }
1433 st = _gvn.transform(st);
1434 set_memory(st, adr_idx);
1435 // Back-to-back stores can only remove intermediate store with DU info
1436 // so push on worklist for optimizer.
1437 if (mem->req() > MemNode::Address && adr == mem->in(MemNode::Address))
1438 record_for_igvn(st);
1439
1440 return st;
1441 }
1442
1443
1444 void GraphKit::pre_barrier(Node* ctl,
1445 Node* obj,
1446 Node* adr,
1447 uint adr_idx,
1448 Node* val,
1449 const TypeOopPtr* val_type,
1450 BasicType bt) {
1451 BarrierSet* bs = Universe::heap()->barrier_set();
1452 set_control(ctl);
1453 switch (bs->kind()) {
1454 case BarrierSet::G1SATBCT:
1455 case BarrierSet::G1SATBCTLogging:
1456 g1_write_barrier_pre(obj, adr, adr_idx, val, val_type, bt);
1457 break;
1458
1459 case BarrierSet::CardTableModRef:
1460 case BarrierSet::CardTableExtension:
1461 case BarrierSet::ModRef:
1462 break;
1463
1464 case BarrierSet::Other:
1465 default :
1466 ShouldNotReachHere();
1467
1468 }
1469 }
1470
1471 void GraphKit::post_barrier(Node* ctl,
1472 Node* store,
1473 Node* obj,
1474 Node* adr,
1475 uint adr_idx,
1476 Node* val,
1477 BasicType bt,
1478 bool use_precise) {
1479 BarrierSet* bs = Universe::heap()->barrier_set();
1480 set_control(ctl);
1481 switch (bs->kind()) {
1482 case BarrierSet::G1SATBCT:
1483 case BarrierSet::G1SATBCTLogging:
1484 g1_write_barrier_post(store, obj, adr, adr_idx, val, bt, use_precise);
1485 break;
1486
1487 case BarrierSet::CardTableModRef:
1488 case BarrierSet::CardTableExtension:
1489 write_barrier_post(store, obj, adr, adr_idx, val, use_precise);
1490 break;
1491
1492 case BarrierSet::ModRef:
1493 break;
1494
1495 case BarrierSet::Other:
1496 default :
1497 ShouldNotReachHere();
1498
1499 }
1500 }
1501
1502 Node* GraphKit::store_oop(Node* ctl,
1503 Node* obj,
1504 Node* adr,
1505 const TypePtr* adr_type,
1506 Node* val,
1507 const TypeOopPtr* val_type,
1508 BasicType bt,
1509 bool use_precise) {
1510
1511 set_control(ctl);
1512 if (stopped()) return top(); // Dead path ?
1513
1514 assert(bt == T_OBJECT, "sanity");
1515 assert(val != NULL, "not dead path");
1516 uint adr_idx = C->get_alias_index(adr_type);
1517 assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1518
1519 pre_barrier(control(), obj, adr, adr_idx, val, val_type, bt);
1520 Node* store = store_to_memory(control(), adr, val, bt, adr_idx);
1521 post_barrier(control(), store, obj, adr, adr_idx, val, bt, use_precise);
1522 return store;
1523 }
1524
1525 // Could be an array or object we don't know at compile time (unsafe ref.)
1526 Node* GraphKit::store_oop_to_unknown(Node* ctl,
1527 Node* obj, // containing obj
1528 Node* adr, // actual adress to store val at
1529 const TypePtr* adr_type,
1530 Node* val,
1531 BasicType bt) {
1532 Compile::AliasType* at = C->alias_type(adr_type);
1533 const TypeOopPtr* val_type = NULL;
1534 if (adr_type->isa_instptr()) {
1535 if (at->field() != NULL) {
1536 // known field. This code is a copy of the do_put_xxx logic.
1537 ciField* field = at->field();
1538 if (!field->type()->is_loaded()) {
1539 val_type = TypeInstPtr::BOTTOM;
1540 } else {
1541 val_type = TypeOopPtr::make_from_klass(field->type()->as_klass());
1542 }
1543 }
1544 } else if (adr_type->isa_aryptr()) {
1545 val_type = adr_type->is_aryptr()->elem()->make_oopptr();
1546 }
1547 if (val_type == NULL) {
1548 val_type = TypeInstPtr::BOTTOM;
1549 }
1550 return store_oop(ctl, obj, adr, adr_type, val, val_type, bt, true);
1551 }
1552
1553
1554 //-------------------------array_element_address-------------------------
1555 Node* GraphKit::array_element_address(Node* ary, Node* idx, BasicType elembt,
1556 const TypeInt* sizetype) {
1557 uint shift = exact_log2(type2aelembytes(elembt));
1558 uint header = arrayOopDesc::base_offset_in_bytes(elembt);
1559
1560 // short-circuit a common case (saves lots of confusing waste motion)
1561 jint idx_con = find_int_con(idx, -1);
1562 if (idx_con >= 0) {
1563 intptr_t offset = header + ((intptr_t)idx_con << shift);
1564 return basic_plus_adr(ary, offset);
1565 }
1566
1567 // must be correct type for alignment purposes
1568 Node* base = basic_plus_adr(ary, header);
1569 #ifdef _LP64
1570 // The scaled index operand to AddP must be a clean 64-bit value.
1571 // Java allows a 32-bit int to be incremented to a negative
1572 // value, which appears in a 64-bit register as a large
1573 // positive number. Using that large positive number as an
1574 // operand in pointer arithmetic has bad consequences.
1575 // On the other hand, 32-bit overflow is rare, and the possibility
1576 // can often be excluded, if we annotate the ConvI2L node with
1577 // a type assertion that its value is known to be a small positive
1578 // number. (The prior range check has ensured this.)
1579 // This assertion is used by ConvI2LNode::Ideal.
1580 int index_max = max_jint - 1; // array size is max_jint, index is one less
1581 if (sizetype != NULL) index_max = sizetype->_hi - 1;
1582 const TypeLong* lidxtype = TypeLong::make(CONST64(0), index_max, Type::WidenMax);
1583 idx = _gvn.transform( new (C, 2) ConvI2LNode(idx, lidxtype) );
1584 #endif
1585 Node* scale = _gvn.transform( new (C, 3) LShiftXNode(idx, intcon(shift)) );
1586 return basic_plus_adr(ary, base, scale);
1587 }
1588
1589 //-------------------------load_array_element-------------------------
1590 Node* GraphKit::load_array_element(Node* ctl, Node* ary, Node* idx, const TypeAryPtr* arytype) {
1591 const Type* elemtype = arytype->elem();
1592 BasicType elembt = elemtype->array_element_basic_type();
1593 Node* adr = array_element_address(ary, idx, elembt, arytype->size());
1594 Node* ld = make_load(ctl, adr, elemtype, elembt, arytype);
1595 return ld;
1596 }
1597
1598 //-------------------------set_arguments_for_java_call-------------------------
1599 // Arguments (pre-popped from the stack) are taken from the JVMS.
1600 void GraphKit::set_arguments_for_java_call(CallJavaNode* call) {
1601 // Add the call arguments:
1602 uint nargs = call->method()->arg_size();
1603 for (uint i = 0; i < nargs; i++) {
1604 Node* arg = argument(i);
1605 call->init_req(i + TypeFunc::Parms, arg);
1606 }
1607 }
1608
1609 //---------------------------set_edges_for_java_call---------------------------
1610 // Connect a newly created call into the current JVMS.
1611 // A return value node (if any) is returned from set_edges_for_java_call.
1612 void GraphKit::set_edges_for_java_call(CallJavaNode* call, bool must_throw, bool separate_io_proj) {
1613
1614 // Add the predefined inputs:
1615 call->init_req( TypeFunc::Control, control() );
1616 call->init_req( TypeFunc::I_O , i_o() );
1617 call->init_req( TypeFunc::Memory , reset_memory() );
1618 call->init_req( TypeFunc::FramePtr, frameptr() );
1619 call->init_req( TypeFunc::ReturnAdr, top() );
1620
1621 add_safepoint_edges(call, must_throw);
1622
1623 Node* xcall = _gvn.transform(call);
1624
1625 if (xcall == top()) {
1626 set_control(top());
1627 return;
1628 }
1629 assert(xcall == call, "call identity is stable");
1630
1631 // Re-use the current map to produce the result.
1632
1633 set_control(_gvn.transform(new (C, 1) ProjNode(call, TypeFunc::Control)));
1634 set_i_o( _gvn.transform(new (C, 1) ProjNode(call, TypeFunc::I_O , separate_io_proj)));
1635 set_all_memory_call(xcall, separate_io_proj);
1636
1637 //return xcall; // no need, caller already has it
1638 }
1639
1640 Node* GraphKit::set_results_for_java_call(CallJavaNode* call, bool separate_io_proj) {
1641 if (stopped()) return top(); // maybe the call folded up?
1642
1643 // Capture the return value, if any.
1644 Node* ret;
1645 if (call->method() == NULL ||
1646 call->method()->return_type()->basic_type() == T_VOID)
1647 ret = top();
1648 else ret = _gvn.transform(new (C, 1) ProjNode(call, TypeFunc::Parms));
1649
1650 // Note: Since any out-of-line call can produce an exception,
1651 // we always insert an I_O projection from the call into the result.
1652
1653 make_slow_call_ex(call, env()->Throwable_klass(), separate_io_proj);
1654
1655 if (separate_io_proj) {
1656 // The caller requested separate projections be used by the fall
1657 // through and exceptional paths, so replace the projections for
1658 // the fall through path.
1659 set_i_o(_gvn.transform( new (C, 1) ProjNode(call, TypeFunc::I_O) ));
1660 set_all_memory(_gvn.transform( new (C, 1) ProjNode(call, TypeFunc::Memory) ));
1661 }
1662 return ret;
1663 }
1664
1665 //--------------------set_predefined_input_for_runtime_call--------------------
1666 // Reading and setting the memory state is way conservative here.
1667 // The real problem is that I am not doing real Type analysis on memory,
1668 // so I cannot distinguish card mark stores from other stores. Across a GC
1669 // point the Store Barrier and the card mark memory has to agree. I cannot
1670 // have a card mark store and its barrier split across the GC point from
1671 // either above or below. Here I get that to happen by reading ALL of memory.
1672 // A better answer would be to separate out card marks from other memory.
1673 // For now, return the input memory state, so that it can be reused
1674 // after the call, if this call has restricted memory effects.
1675 Node* GraphKit::set_predefined_input_for_runtime_call(SafePointNode* call) {
1676 // Set fixed predefined input arguments
1677 Node* memory = reset_memory();
1678 call->init_req( TypeFunc::Control, control() );
1679 call->init_req( TypeFunc::I_O, top() ); // does no i/o
1680 call->init_req( TypeFunc::Memory, memory ); // may gc ptrs
1681 call->init_req( TypeFunc::FramePtr, frameptr() );
1682 call->init_req( TypeFunc::ReturnAdr, top() );
1683 return memory;
1684 }
1685
1686 //-------------------set_predefined_output_for_runtime_call--------------------
1687 // Set control and memory (not i_o) from the call.
1688 // If keep_mem is not NULL, use it for the output state,
1689 // except for the RawPtr output of the call, if hook_mem is TypeRawPtr::BOTTOM.
1690 // If hook_mem is NULL, this call produces no memory effects at all.
1691 // If hook_mem is a Java-visible memory slice (such as arraycopy operands),
1692 // then only that memory slice is taken from the call.
1693 // In the last case, we must put an appropriate memory barrier before
1694 // the call, so as to create the correct anti-dependencies on loads
1695 // preceding the call.
1696 void GraphKit::set_predefined_output_for_runtime_call(Node* call,
1697 Node* keep_mem,
1698 const TypePtr* hook_mem) {
1699 // no i/o
1700 set_control(_gvn.transform( new (C, 1) ProjNode(call,TypeFunc::Control) ));
1701 if (keep_mem) {
1702 // First clone the existing memory state
1703 set_all_memory(keep_mem);
1704 if (hook_mem != NULL) {
1705 // Make memory for the call
1706 Node* mem = _gvn.transform( new (C, 1) ProjNode(call, TypeFunc::Memory) );
1707 // Set the RawPtr memory state only. This covers all the heap top/GC stuff
1708 // We also use hook_mem to extract specific effects from arraycopy stubs.
1709 set_memory(mem, hook_mem);
1710 }
1711 // ...else the call has NO memory effects.
1712
1713 // Make sure the call advertises its memory effects precisely.
1714 // This lets us build accurate anti-dependences in gcm.cpp.
1715 assert(C->alias_type(call->adr_type()) == C->alias_type(hook_mem),
1716 "call node must be constructed correctly");
1717 } else {
1718 assert(hook_mem == NULL, "");
1719 // This is not a "slow path" call; all memory comes from the call.
1720 set_all_memory_call(call);
1721 }
1722 }
1723
1724
1725 // Replace the call with the current state of the kit.
1726 void GraphKit::replace_call(CallNode* call, Node* result) {
1727 JVMState* ejvms = NULL;
1728 if (has_exceptions()) {
1729 ejvms = transfer_exceptions_into_jvms();
1730 }
1731
1732 SafePointNode* final_state = stop();
1733
1734 // Find all the needed outputs of this call
1735 CallProjections callprojs;
1736 call->extract_projections(&callprojs, true);
1737
1738 // Replace all the old call edges with the edges from the inlining result
1739 C->gvn_replace_by(callprojs.fallthrough_catchproj, final_state->in(TypeFunc::Control));
1740 C->gvn_replace_by(callprojs.fallthrough_memproj, final_state->in(TypeFunc::Memory));
1741 C->gvn_replace_by(callprojs.fallthrough_ioproj, final_state->in(TypeFunc::I_O));
1742
1743 // Replace the result with the new result if it exists and is used
1744 if (callprojs.resproj != NULL && result != NULL) {
1745 C->gvn_replace_by(callprojs.resproj, result);
1746 }
1747
1748 if (ejvms == NULL) {
1749 // No exception edges to simply kill off those paths
1750 C->gvn_replace_by(callprojs.catchall_catchproj, C->top());
1751 C->gvn_replace_by(callprojs.catchall_memproj, C->top());
1752 C->gvn_replace_by(callprojs.catchall_ioproj, C->top());
1753
1754 // Replace the old exception object with top
1755 if (callprojs.exobj != NULL) {
1756 C->gvn_replace_by(callprojs.exobj, C->top());
1757 }
1758 } else {
1759 GraphKit ekit(ejvms);
1760
1761 // Load my combined exception state into the kit, with all phis transformed:
1762 SafePointNode* ex_map = ekit.combine_and_pop_all_exception_states();
1763
1764 Node* ex_oop = ekit.use_exception_state(ex_map);
1765
1766 C->gvn_replace_by(callprojs.catchall_catchproj, ekit.control());
1767 C->gvn_replace_by(callprojs.catchall_memproj, ekit.reset_memory());
1768 C->gvn_replace_by(callprojs.catchall_ioproj, ekit.i_o());
1769
1770 // Replace the old exception object with the newly created one
1771 if (callprojs.exobj != NULL) {
1772 C->gvn_replace_by(callprojs.exobj, ex_oop);
1773 }
1774 }
1775
1776 // Disconnect the call from the graph
1777 call->disconnect_inputs(NULL);
1778 C->gvn_replace_by(call, C->top());
1779 }
1780
1781
1782 //------------------------------increment_counter------------------------------
1783 // for statistics: increment a VM counter by 1
1784
1785 void GraphKit::increment_counter(address counter_addr) {
1786 Node* adr1 = makecon(TypeRawPtr::make(counter_addr));
1787 increment_counter(adr1);
1788 }
1789
1790 void GraphKit::increment_counter(Node* counter_addr) {
1791 int adr_type = Compile::AliasIdxRaw;
1792 Node* cnt = make_load(NULL, counter_addr, TypeInt::INT, T_INT, adr_type);
1793 Node* incr = _gvn.transform(new (C, 3) AddINode(cnt, _gvn.intcon(1)));
1794 store_to_memory( NULL, counter_addr, incr, T_INT, adr_type );
1795 }
1796
1797
1798 //------------------------------uncommon_trap----------------------------------
1799 // Bail out to the interpreter in mid-method. Implemented by calling the
1800 // uncommon_trap blob. This helper function inserts a runtime call with the
1801 // right debug info.
1802 void GraphKit::uncommon_trap(int trap_request,
1803 ciKlass* klass, const char* comment,
1804 bool must_throw,
1805 bool keep_exact_action) {
1806 if (failing()) stop();
1807 if (stopped()) return; // trap reachable?
1808
1809 // Note: If ProfileTraps is true, and if a deopt. actually
1810 // occurs here, the runtime will make sure an MDO exists. There is
1811 // no need to call method()->build_method_data() at this point.
1812
1813 #ifdef ASSERT
1814 if (!must_throw) {
1815 // Make sure the stack has at least enough depth to execute
1816 // the current bytecode.
1817 int inputs, ignore;
1818 if (compute_stack_effects(inputs, ignore)) {
1819 assert(sp() >= inputs, "must have enough JVMS stack to execute");
1820 // It is a frequent error in library_call.cpp to issue an
1821 // uncommon trap with the _sp value already popped.
1822 }
1823 }
1824 #endif
1825
1826 Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
1827 Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
1828
1829 switch (action) {
1830 case Deoptimization::Action_maybe_recompile:
1831 case Deoptimization::Action_reinterpret:
1832 // Temporary fix for 6529811 to allow virtual calls to be sure they
1833 // get the chance to go from mono->bi->mega
1834 if (!keep_exact_action &&
1835 Deoptimization::trap_request_index(trap_request) < 0 &&
1836 too_many_recompiles(reason)) {
1837 // This BCI is causing too many recompilations.
1838 action = Deoptimization::Action_none;
1839 trap_request = Deoptimization::make_trap_request(reason, action);
1840 } else {
1841 C->set_trap_can_recompile(true);
1842 }
1843 break;
1844 case Deoptimization::Action_make_not_entrant:
1845 C->set_trap_can_recompile(true);
1846 break;
1847 #ifdef ASSERT
1848 case Deoptimization::Action_none:
1849 case Deoptimization::Action_make_not_compilable:
1850 break;
1851 default:
1852 assert(false, "bad action");
1853 #endif
1854 }
1855
1856 if (TraceOptoParse) {
1857 char buf[100];
1858 tty->print_cr("Uncommon trap %s at bci:%d",
1859 Deoptimization::format_trap_request(buf, sizeof(buf),
1860 trap_request), bci());
1861 }
1862
1863 CompileLog* log = C->log();
1864 if (log != NULL) {
1865 int kid = (klass == NULL)? -1: log->identify(klass);
1866 log->begin_elem("uncommon_trap bci='%d'", bci());
1867 char buf[100];
1868 log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf),
1869 trap_request));
1870 if (kid >= 0) log->print(" klass='%d'", kid);
1871 if (comment != NULL) log->print(" comment='%s'", comment);
1872 log->end_elem();
1873 }
1874
1875 // Make sure any guarding test views this path as very unlikely
1876 Node *i0 = control()->in(0);
1877 if (i0 != NULL && i0->is_If()) { // Found a guarding if test?
1878 IfNode *iff = i0->as_If();
1879 float f = iff->_prob; // Get prob
1880 if (control()->Opcode() == Op_IfTrue) {
1881 if (f > PROB_UNLIKELY_MAG(4))
1882 iff->_prob = PROB_MIN;
1883 } else {
1884 if (f < PROB_LIKELY_MAG(4))
1885 iff->_prob = PROB_MAX;
1886 }
1887 }
1888
1889 // Clear out dead values from the debug info.
1890 kill_dead_locals();
1891
1892 // Now insert the uncommon trap subroutine call
1893 address call_addr = SharedRuntime::uncommon_trap_blob()->instructions_begin();
1894 const TypePtr* no_memory_effects = NULL;
1895 // Pass the index of the class to be loaded
1896 Node* call = make_runtime_call(RC_NO_LEAF | RC_UNCOMMON |
1897 (must_throw ? RC_MUST_THROW : 0),
1898 OptoRuntime::uncommon_trap_Type(),
1899 call_addr, "uncommon_trap", no_memory_effects,
1900 intcon(trap_request));
1901 assert(call->as_CallStaticJava()->uncommon_trap_request() == trap_request,
1902 "must extract request correctly from the graph");
1903 assert(trap_request != 0, "zero value reserved by uncommon_trap_request");
1904
1905 call->set_req(TypeFunc::ReturnAdr, returnadr());
1906 // The debug info is the only real input to this call.
1907
1908 // Halt-and-catch fire here. The above call should never return!
1909 HaltNode* halt = new(C, TypeFunc::Parms) HaltNode(control(), frameptr());
1910 _gvn.set_type_bottom(halt);
1911 root()->add_req(halt);
1912
1913 stop_and_kill_map();
1914 }
1915
1916
1917 //--------------------------just_allocated_object------------------------------
1918 // Report the object that was just allocated.
1919 // It must be the case that there are no intervening safepoints.
1920 // We use this to determine if an object is so "fresh" that
1921 // it does not require card marks.
1922 Node* GraphKit::just_allocated_object(Node* current_control) {
1923 if (C->recent_alloc_ctl() == current_control)
1924 return C->recent_alloc_obj();
1925 return NULL;
1926 }
1927
1928
1929 void GraphKit::round_double_arguments(ciMethod* dest_method) {
1930 // (Note: TypeFunc::make has a cache that makes this fast.)
1931 const TypeFunc* tf = TypeFunc::make(dest_method);
1932 int nargs = tf->_domain->_cnt - TypeFunc::Parms;
1933 for (int j = 0; j < nargs; j++) {
1934 const Type *targ = tf->_domain->field_at(j + TypeFunc::Parms);
1935 if( targ->basic_type() == T_DOUBLE ) {
1936 // If any parameters are doubles, they must be rounded before
1937 // the call, dstore_rounding does gvn.transform
1938 Node *arg = argument(j);
1939 arg = dstore_rounding(arg);
1940 set_argument(j, arg);
1941 }
1942 }
1943 }
1944
1945 void GraphKit::round_double_result(ciMethod* dest_method) {
1946 // A non-strict method may return a double value which has an extended
1947 // exponent, but this must not be visible in a caller which is 'strict'
1948 // If a strict caller invokes a non-strict callee, round a double result
1949
1950 BasicType result_type = dest_method->return_type()->basic_type();
1951 assert( method() != NULL, "must have caller context");
1952 if( result_type == T_DOUBLE && method()->is_strict() && !dest_method->is_strict() ) {
1953 // Destination method's return value is on top of stack
1954 // dstore_rounding() does gvn.transform
1955 Node *result = pop_pair();
1956 result = dstore_rounding(result);
1957 push_pair(result);
1958 }
1959 }
1960
1961 // rounding for strict float precision conformance
1962 Node* GraphKit::precision_rounding(Node* n) {
1963 return UseStrictFP && _method->flags().is_strict()
1964 && UseSSE == 0 && Matcher::strict_fp_requires_explicit_rounding
1965 ? _gvn.transform( new (C, 2) RoundFloatNode(0, n) )
1966 : n;
1967 }
1968
1969 // rounding for strict double precision conformance
1970 Node* GraphKit::dprecision_rounding(Node *n) {
1971 return UseStrictFP && _method->flags().is_strict()
1972 && UseSSE <= 1 && Matcher::strict_fp_requires_explicit_rounding
1973 ? _gvn.transform( new (C, 2) RoundDoubleNode(0, n) )
1974 : n;
1975 }
1976
1977 // rounding for non-strict double stores
1978 Node* GraphKit::dstore_rounding(Node* n) {
1979 return Matcher::strict_fp_requires_explicit_rounding
1980 && UseSSE <= 1
1981 ? _gvn.transform( new (C, 2) RoundDoubleNode(0, n) )
1982 : n;
1983 }
1984
1985 //=============================================================================
1986 // Generate a fast path/slow path idiom. Graph looks like:
1987 // [foo] indicates that 'foo' is a parameter
1988 //
1989 // [in] NULL
1990 // \ /
1991 // CmpP
1992 // Bool ne
1993 // If
1994 // / \
1995 // True False-<2>
1996 // / |
1997 // / cast_not_null
1998 // Load | | ^
1999 // [fast_test] | |
2000 // gvn to opt_test | |
2001 // / \ | <1>
2002 // True False |
2003 // | \\ |
2004 // [slow_call] \[fast_result]
2005 // Ctl Val \ \
2006 // | \ \
2007 // Catch <1> \ \
2008 // / \ ^ \ \
2009 // Ex No_Ex | \ \
2010 // | \ \ | \ <2> \
2011 // ... \ [slow_res] | | \ [null_result]
2012 // \ \--+--+--- | |
2013 // \ | / \ | /
2014 // --------Region Phi
2015 //
2016 //=============================================================================
2017 // Code is structured as a series of driver functions all called 'do_XXX' that
2018 // call a set of helper functions. Helper functions first, then drivers.
2019
2020 //------------------------------null_check_oop---------------------------------
2021 // Null check oop. Set null-path control into Region in slot 3.
2022 // Make a cast-not-nullness use the other not-null control. Return cast.
2023 Node* GraphKit::null_check_oop(Node* value, Node* *null_control,
2024 bool never_see_null) {
2025 // Initial NULL check taken path
2026 (*null_control) = top();
2027 Node* cast = null_check_common(value, T_OBJECT, false, null_control);
2028
2029 // Generate uncommon_trap:
2030 if (never_see_null && (*null_control) != top()) {
2031 // If we see an unexpected null at a check-cast we record it and force a
2032 // recompile; the offending check-cast will be compiled to handle NULLs.
2033 // If we see more than one offending BCI, then all checkcasts in the
2034 // method will be compiled to handle NULLs.
2035 PreserveJVMState pjvms(this);
2036 set_control(*null_control);
2037 replace_in_map(value, null());
2038 uncommon_trap(Deoptimization::Reason_null_check,
2039 Deoptimization::Action_make_not_entrant);
2040 (*null_control) = top(); // NULL path is dead
2041 }
2042
2043 // Cast away null-ness on the result
2044 return cast;
2045 }
2046
2047 //------------------------------opt_iff----------------------------------------
2048 // Optimize the fast-check IfNode. Set the fast-path region slot 2.
2049 // Return slow-path control.
2050 Node* GraphKit::opt_iff(Node* region, Node* iff) {
2051 IfNode *opt_iff = _gvn.transform(iff)->as_If();
2052
2053 // Fast path taken; set region slot 2
2054 Node *fast_taken = _gvn.transform( new (C, 1) IfFalseNode(opt_iff) );
2055 region->init_req(2,fast_taken); // Capture fast-control
2056
2057 // Fast path not-taken, i.e. slow path
2058 Node *slow_taken = _gvn.transform( new (C, 1) IfTrueNode(opt_iff) );
2059 return slow_taken;
2060 }
2061
2062 //-----------------------------make_runtime_call-------------------------------
2063 Node* GraphKit::make_runtime_call(int flags,
2064 const TypeFunc* call_type, address call_addr,
2065 const char* call_name,
2066 const TypePtr* adr_type,
2067 // The following parms are all optional.
2068 // The first NULL ends the list.
2069 Node* parm0, Node* parm1,
2070 Node* parm2, Node* parm3,
2071 Node* parm4, Node* parm5,
2072 Node* parm6, Node* parm7) {
2073 // Slow-path call
2074 int size = call_type->domain()->cnt();
2075 bool is_leaf = !(flags & RC_NO_LEAF);
2076 bool has_io = (!is_leaf && !(flags & RC_NO_IO));
2077 if (call_name == NULL) {
2078 assert(!is_leaf, "must supply name for leaf");
2079 call_name = OptoRuntime::stub_name(call_addr);
2080 }
2081 CallNode* call;
2082 if (!is_leaf) {
2083 call = new(C, size) CallStaticJavaNode(call_type, call_addr, call_name,
2084 bci(), adr_type);
2085 } else if (flags & RC_NO_FP) {
2086 call = new(C, size) CallLeafNoFPNode(call_type, call_addr, call_name, adr_type);
2087 } else {
2088 call = new(C, size) CallLeafNode(call_type, call_addr, call_name, adr_type);
2089 }
2090
2091 // The following is similar to set_edges_for_java_call,
2092 // except that the memory effects of the call are restricted to AliasIdxRaw.
2093
2094 // Slow path call has no side-effects, uses few values
2095 bool wide_in = !(flags & RC_NARROW_MEM);
2096 bool wide_out = (C->get_alias_index(adr_type) == Compile::AliasIdxBot);
2097
2098 Node* prev_mem = NULL;
2099 if (wide_in) {
2100 prev_mem = set_predefined_input_for_runtime_call(call);
2101 } else {
2102 assert(!wide_out, "narrow in => narrow out");
2103 Node* narrow_mem = memory(adr_type);
2104 prev_mem = reset_memory();
2105 map()->set_memory(narrow_mem);
2106 set_predefined_input_for_runtime_call(call);
2107 }
2108
2109 // Hook each parm in order. Stop looking at the first NULL.
2110 if (parm0 != NULL) { call->init_req(TypeFunc::Parms+0, parm0);
2111 if (parm1 != NULL) { call->init_req(TypeFunc::Parms+1, parm1);
2112 if (parm2 != NULL) { call->init_req(TypeFunc::Parms+2, parm2);
2113 if (parm3 != NULL) { call->init_req(TypeFunc::Parms+3, parm3);
2114 if (parm4 != NULL) { call->init_req(TypeFunc::Parms+4, parm4);
2115 if (parm5 != NULL) { call->init_req(TypeFunc::Parms+5, parm5);
2116 if (parm6 != NULL) { call->init_req(TypeFunc::Parms+6, parm6);
2117 if (parm7 != NULL) { call->init_req(TypeFunc::Parms+7, parm7);
2118 /* close each nested if ===> */ } } } } } } } }
2119 assert(call->in(call->req()-1) != NULL, "must initialize all parms");
2120
2121 if (!is_leaf) {
2122 // Non-leaves can block and take safepoints:
2123 add_safepoint_edges(call, ((flags & RC_MUST_THROW) != 0));
2124 }
2125 // Non-leaves can throw exceptions:
2126 if (has_io) {
2127 call->set_req(TypeFunc::I_O, i_o());
2128 }
2129
2130 if (flags & RC_UNCOMMON) {
2131 // Set the count to a tiny probability. Cf. Estimate_Block_Frequency.
2132 // (An "if" probability corresponds roughly to an unconditional count.
2133 // Sort of.)
2134 call->set_cnt(PROB_UNLIKELY_MAG(4));
2135 }
2136
2137 Node* c = _gvn.transform(call);
2138 assert(c == call, "cannot disappear");
2139
2140 if (wide_out) {
2141 // Slow path call has full side-effects.
2142 set_predefined_output_for_runtime_call(call);
2143 } else {
2144 // Slow path call has few side-effects, and/or sets few values.
2145 set_predefined_output_for_runtime_call(call, prev_mem, adr_type);
2146 }
2147
2148 if (has_io) {
2149 set_i_o(_gvn.transform(new (C, 1) ProjNode(call, TypeFunc::I_O)));
2150 }
2151 return call;
2152
2153 }
2154
2155 //------------------------------merge_memory-----------------------------------
2156 // Merge memory from one path into the current memory state.
2157 void GraphKit::merge_memory(Node* new_mem, Node* region, int new_path) {
2158 for (MergeMemStream mms(merged_memory(), new_mem->as_MergeMem()); mms.next_non_empty2(); ) {
2159 Node* old_slice = mms.force_memory();
2160 Node* new_slice = mms.memory2();
2161 if (old_slice != new_slice) {
2162 PhiNode* phi;
2163 if (new_slice->is_Phi() && new_slice->as_Phi()->region() == region) {
2164 phi = new_slice->as_Phi();
2165 #ifdef ASSERT
2166 if (old_slice->is_Phi() && old_slice->as_Phi()->region() == region)
2167 old_slice = old_slice->in(new_path);
2168 // Caller is responsible for ensuring that any pre-existing
2169 // phis are already aware of old memory.
2170 int old_path = (new_path > 1) ? 1 : 2; // choose old_path != new_path
2171 assert(phi->in(old_path) == old_slice, "pre-existing phis OK");
2172 #endif
2173 mms.set_memory(phi);
2174 } else {
2175 phi = PhiNode::make(region, old_slice, Type::MEMORY, mms.adr_type(C));
2176 _gvn.set_type(phi, Type::MEMORY);
2177 phi->set_req(new_path, new_slice);
2178 mms.set_memory(_gvn.transform(phi)); // assume it is complete
2179 }
2180 }
2181 }
2182 }
2183
2184 //------------------------------make_slow_call_ex------------------------------
2185 // Make the exception handler hookups for the slow call
2186 void GraphKit::make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj) {
2187 if (stopped()) return;
2188
2189 // Make a catch node with just two handlers: fall-through and catch-all
2190 Node* i_o = _gvn.transform( new (C, 1) ProjNode(call, TypeFunc::I_O, separate_io_proj) );
2191 Node* catc = _gvn.transform( new (C, 2) CatchNode(control(), i_o, 2) );
2192 Node* norm = _gvn.transform( new (C, 1) CatchProjNode(catc, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci) );
2193 Node* excp = _gvn.transform( new (C, 1) CatchProjNode(catc, CatchProjNode::catch_all_index, CatchProjNode::no_handler_bci) );
2194
2195 { PreserveJVMState pjvms(this);
2196 set_control(excp);
2197 set_i_o(i_o);
2198
2199 if (excp != top()) {
2200 // Create an exception state also.
2201 // Use an exact type if the caller has specified a specific exception.
2202 const Type* ex_type = TypeOopPtr::make_from_klass_unique(ex_klass)->cast_to_ptr_type(TypePtr::NotNull);
2203 Node* ex_oop = new (C, 2) CreateExNode(ex_type, control(), i_o);
2204 add_exception_state(make_exception_state(_gvn.transform(ex_oop)));
2205 }
2206 }
2207
2208 // Get the no-exception control from the CatchNode.
2209 set_control(norm);
2210 }
2211
2212
2213 //-------------------------------gen_subtype_check-----------------------------
2214 // Generate a subtyping check. Takes as input the subtype and supertype.
2215 // Returns 2 values: sets the default control() to the true path and returns
2216 // the false path. Only reads invariant memory; sets no (visible) memory.
2217 // The PartialSubtypeCheckNode sets the hidden 1-word cache in the encoding
2218 // but that's not exposed to the optimizer. This call also doesn't take in an
2219 // Object; if you wish to check an Object you need to load the Object's class
2220 // prior to coming here.
2221 Node* GraphKit::gen_subtype_check(Node* subklass, Node* superklass) {
2222 // Fast check for identical types, perhaps identical constants.
2223 // The types can even be identical non-constants, in cases
2224 // involving Array.newInstance, Object.clone, etc.
2225 if (subklass == superklass)
2226 return top(); // false path is dead; no test needed.
2227
2228 if (_gvn.type(superklass)->singleton()) {
2229 ciKlass* superk = _gvn.type(superklass)->is_klassptr()->klass();
2230 ciKlass* subk = _gvn.type(subklass)->is_klassptr()->klass();
2231
2232 // In the common case of an exact superklass, try to fold up the
2233 // test before generating code. You may ask, why not just generate
2234 // the code and then let it fold up? The answer is that the generated
2235 // code will necessarily include null checks, which do not always
2236 // completely fold away. If they are also needless, then they turn
2237 // into a performance loss. Example:
2238 // Foo[] fa = blah(); Foo x = fa[0]; fa[1] = x;
2239 // Here, the type of 'fa' is often exact, so the store check
2240 // of fa[1]=x will fold up, without testing the nullness of x.
2241 switch (static_subtype_check(superk, subk)) {
2242 case SSC_always_false:
2243 {
2244 Node* always_fail = control();
2245 set_control(top());
2246 return always_fail;
2247 }
2248 case SSC_always_true:
2249 return top();
2250 case SSC_easy_test:
2251 {
2252 // Just do a direct pointer compare and be done.
2253 Node* cmp = _gvn.transform( new(C, 3) CmpPNode(subklass, superklass) );
2254 Node* bol = _gvn.transform( new(C, 2) BoolNode(cmp, BoolTest::eq) );
2255 IfNode* iff = create_and_xform_if(control(), bol, PROB_STATIC_FREQUENT, COUNT_UNKNOWN);
2256 set_control( _gvn.transform( new(C, 1) IfTrueNode (iff) ) );
2257 return _gvn.transform( new(C, 1) IfFalseNode(iff) );
2258 }
2259 case SSC_full_test:
2260 break;
2261 default:
2262 ShouldNotReachHere();
2263 }
2264 }
2265
2266 // %%% Possible further optimization: Even if the superklass is not exact,
2267 // if the subklass is the unique subtype of the superklass, the check
2268 // will always succeed. We could leave a dependency behind to ensure this.
2269
2270 // First load the super-klass's check-offset
2271 Node *p1 = basic_plus_adr( superklass, superklass, sizeof(oopDesc) + Klass::super_check_offset_offset_in_bytes() );
2272 Node *chk_off = _gvn.transform( new (C, 3) LoadINode( NULL, memory(p1), p1, _gvn.type(p1)->is_ptr() ) );
2273 int cacheoff_con = sizeof(oopDesc) + Klass::secondary_super_cache_offset_in_bytes();
2274 bool might_be_cache = (find_int_con(chk_off, cacheoff_con) == cacheoff_con);
2275
2276 // Load from the sub-klass's super-class display list, or a 1-word cache of
2277 // the secondary superclass list, or a failing value with a sentinel offset
2278 // if the super-klass is an interface or exceptionally deep in the Java
2279 // hierarchy and we have to scan the secondary superclass list the hard way.
2280 // Worst-case type is a little odd: NULL is allowed as a result (usually
2281 // klass loads can never produce a NULL).
2282 Node *chk_off_X = ConvI2X(chk_off);
2283 Node *p2 = _gvn.transform( new (C, 4) AddPNode(subklass,subklass,chk_off_X) );
2284 // For some types like interfaces the following loadKlass is from a 1-word
2285 // cache which is mutable so can't use immutable memory. Other
2286 // types load from the super-class display table which is immutable.
2287 Node *kmem = might_be_cache ? memory(p2) : immutable_memory();
2288 Node *nkls = _gvn.transform( LoadKlassNode::make( _gvn, kmem, p2, _gvn.type(p2)->is_ptr(), TypeKlassPtr::OBJECT_OR_NULL ) );
2289
2290 // Compile speed common case: ARE a subtype and we canNOT fail
2291 if( superklass == nkls )
2292 return top(); // false path is dead; no test needed.
2293
2294 // See if we get an immediate positive hit. Happens roughly 83% of the
2295 // time. Test to see if the value loaded just previously from the subklass
2296 // is exactly the superklass.
2297 Node *cmp1 = _gvn.transform( new (C, 3) CmpPNode( superklass, nkls ) );
2298 Node *bol1 = _gvn.transform( new (C, 2) BoolNode( cmp1, BoolTest::eq ) );
2299 IfNode *iff1 = create_and_xform_if( control(), bol1, PROB_LIKELY(0.83f), COUNT_UNKNOWN );
2300 Node *iftrue1 = _gvn.transform( new (C, 1) IfTrueNode ( iff1 ) );
2301 set_control( _gvn.transform( new (C, 1) IfFalseNode( iff1 ) ) );
2302
2303 // Compile speed common case: Check for being deterministic right now. If
2304 // chk_off is a constant and not equal to cacheoff then we are NOT a
2305 // subklass. In this case we need exactly the 1 test above and we can
2306 // return those results immediately.
2307 if (!might_be_cache) {
2308 Node* not_subtype_ctrl = control();
2309 set_control(iftrue1); // We need exactly the 1 test above
2310 return not_subtype_ctrl;
2311 }
2312
2313 // Gather the various success & failures here
2314 RegionNode *r_ok_subtype = new (C, 4) RegionNode(4);
2315 record_for_igvn(r_ok_subtype);
2316 RegionNode *r_not_subtype = new (C, 3) RegionNode(3);
2317 record_for_igvn(r_not_subtype);
2318
2319 r_ok_subtype->init_req(1, iftrue1);
2320
2321 // Check for immediate negative hit. Happens roughly 11% of the time (which
2322 // is roughly 63% of the remaining cases). Test to see if the loaded
2323 // check-offset points into the subklass display list or the 1-element
2324 // cache. If it points to the display (and NOT the cache) and the display
2325 // missed then it's not a subtype.
2326 Node *cacheoff = _gvn.intcon(cacheoff_con);
2327 Node *cmp2 = _gvn.transform( new (C, 3) CmpINode( chk_off, cacheoff ) );
2328 Node *bol2 = _gvn.transform( new (C, 2) BoolNode( cmp2, BoolTest::ne ) );
2329 IfNode *iff2 = create_and_xform_if( control(), bol2, PROB_LIKELY(0.63f), COUNT_UNKNOWN );
2330 r_not_subtype->init_req(1, _gvn.transform( new (C, 1) IfTrueNode (iff2) ) );
2331 set_control( _gvn.transform( new (C, 1) IfFalseNode(iff2) ) );
2332
2333 // Check for self. Very rare to get here, but it is taken 1/3 the time.
2334 // No performance impact (too rare) but allows sharing of secondary arrays
2335 // which has some footprint reduction.
2336 Node *cmp3 = _gvn.transform( new (C, 3) CmpPNode( subklass, superklass ) );
2337 Node *bol3 = _gvn.transform( new (C, 2) BoolNode( cmp3, BoolTest::eq ) );
2338 IfNode *iff3 = create_and_xform_if( control(), bol3, PROB_LIKELY(0.36f), COUNT_UNKNOWN );
2339 r_ok_subtype->init_req(2, _gvn.transform( new (C, 1) IfTrueNode ( iff3 ) ) );
2340 set_control( _gvn.transform( new (C, 1) IfFalseNode( iff3 ) ) );
2341
2342 // -- Roads not taken here: --
2343 // We could also have chosen to perform the self-check at the beginning
2344 // of this code sequence, as the assembler does. This would not pay off
2345 // the same way, since the optimizer, unlike the assembler, can perform
2346 // static type analysis to fold away many successful self-checks.
2347 // Non-foldable self checks work better here in second position, because
2348 // the initial primary superclass check subsumes a self-check for most
2349 // types. An exception would be a secondary type like array-of-interface,
2350 // which does not appear in its own primary supertype display.
2351 // Finally, we could have chosen to move the self-check into the
2352 // PartialSubtypeCheckNode, and from there out-of-line in a platform
2353 // dependent manner. But it is worthwhile to have the check here,
2354 // where it can be perhaps be optimized. The cost in code space is
2355 // small (register compare, branch).
2356
2357 // Now do a linear scan of the secondary super-klass array. Again, no real
2358 // performance impact (too rare) but it's gotta be done.
2359 // Since the code is rarely used, there is no penalty for moving it
2360 // out of line, and it can only improve I-cache density.
2361 // The decision to inline or out-of-line this final check is platform
2362 // dependent, and is found in the AD file definition of PartialSubtypeCheck.
2363 Node* psc = _gvn.transform(
2364 new (C, 3) PartialSubtypeCheckNode(control(), subklass, superklass) );
2365
2366 Node *cmp4 = _gvn.transform( new (C, 3) CmpPNode( psc, null() ) );
2367 Node *bol4 = _gvn.transform( new (C, 2) BoolNode( cmp4, BoolTest::ne ) );
2368 IfNode *iff4 = create_and_xform_if( control(), bol4, PROB_FAIR, COUNT_UNKNOWN );
2369 r_not_subtype->init_req(2, _gvn.transform( new (C, 1) IfTrueNode (iff4) ) );
2370 r_ok_subtype ->init_req(3, _gvn.transform( new (C, 1) IfFalseNode(iff4) ) );
2371
2372 // Return false path; set default control to true path.
2373 set_control( _gvn.transform(r_ok_subtype) );
2374 return _gvn.transform(r_not_subtype);
2375 }
2376
2377 //----------------------------static_subtype_check-----------------------------
2378 // Shortcut important common cases when superklass is exact:
2379 // (0) superklass is java.lang.Object (can occur in reflective code)
2380 // (1) subklass is already limited to a subtype of superklass => always ok
2381 // (2) subklass does not overlap with superklass => always fail
2382 // (3) superklass has NO subtypes and we can check with a simple compare.
2383 int GraphKit::static_subtype_check(ciKlass* superk, ciKlass* subk) {
2384 if (StressReflectiveCode) {
2385 return SSC_full_test; // Let caller generate the general case.
2386 }
2387
2388 if (superk == env()->Object_klass()) {
2389 return SSC_always_true; // (0) this test cannot fail
2390 }
2391
2392 ciType* superelem = superk;
2393 if (superelem->is_array_klass())
2394 superelem = superelem->as_array_klass()->base_element_type();
2395
2396 if (!subk->is_interface()) { // cannot trust static interface types yet
2397 if (subk->is_subtype_of(superk)) {
2398 return SSC_always_true; // (1) false path dead; no dynamic test needed
2399 }
2400 if (!(superelem->is_klass() && superelem->as_klass()->is_interface()) &&
2401 !superk->is_subtype_of(subk)) {
2402 return SSC_always_false;
2403 }
2404 }
2405
2406 // If casting to an instance klass, it must have no subtypes
2407 if (superk->is_interface()) {
2408 // Cannot trust interfaces yet.
2409 // %%% S.B. superk->nof_implementors() == 1
2410 } else if (superelem->is_instance_klass()) {
2411 ciInstanceKlass* ik = superelem->as_instance_klass();
2412 if (!ik->has_subklass() && !ik->is_interface()) {
2413 if (!ik->is_final()) {
2414 // Add a dependency if there is a chance of a later subclass.
2415 C->dependencies()->assert_leaf_type(ik);
2416 }
2417 return SSC_easy_test; // (3) caller can do a simple ptr comparison
2418 }
2419 } else {
2420 // A primitive array type has no subtypes.
2421 return SSC_easy_test; // (3) caller can do a simple ptr comparison
2422 }
2423
2424 return SSC_full_test;
2425 }
2426
2427 // Profile-driven exact type check:
2428 Node* GraphKit::type_check_receiver(Node* receiver, ciKlass* klass,
2429 float prob,
2430 Node* *casted_receiver) {
2431 const TypeKlassPtr* tklass = TypeKlassPtr::make(klass);
2432 Node* recv_klass = load_object_klass(receiver);
2433 Node* want_klass = makecon(tklass);
2434 Node* cmp = _gvn.transform( new(C, 3) CmpPNode(recv_klass, want_klass) );
2435 Node* bol = _gvn.transform( new(C, 2) BoolNode(cmp, BoolTest::eq) );
2436 IfNode* iff = create_and_xform_if(control(), bol, prob, COUNT_UNKNOWN);
2437 set_control( _gvn.transform( new(C, 1) IfTrueNode (iff) ));
2438 Node* fail = _gvn.transform( new(C, 1) IfFalseNode(iff) );
2439
2440 const TypeOopPtr* recv_xtype = tklass->as_instance_type();
2441 assert(recv_xtype->klass_is_exact(), "");
2442
2443 // Subsume downstream occurrences of receiver with a cast to
2444 // recv_xtype, since now we know what the type will be.
2445 Node* cast = new(C, 2) CheckCastPPNode(control(), receiver, recv_xtype);
2446 (*casted_receiver) = _gvn.transform(cast);
2447 // (User must make the replace_in_map call.)
2448
2449 return fail;
2450 }
2451
2452
2453 //-------------------------------gen_instanceof--------------------------------
2454 // Generate an instance-of idiom. Used by both the instance-of bytecode
2455 // and the reflective instance-of call.
2456 Node* GraphKit::gen_instanceof( Node *subobj, Node* superklass ) {
2457 C->set_has_split_ifs(true); // Has chance for split-if optimization
2458 assert( !stopped(), "dead parse path should be checked in callers" );
2459 assert(!TypePtr::NULL_PTR->higher_equal(_gvn.type(superklass)->is_klassptr()),
2460 "must check for not-null not-dead klass in callers");
2461
2462 // Make the merge point
2463 enum { _obj_path = 1, _fail_path, _null_path, PATH_LIMIT };
2464 RegionNode* region = new(C, PATH_LIMIT) RegionNode(PATH_LIMIT);
2465 Node* phi = new(C, PATH_LIMIT) PhiNode(region, TypeInt::BOOL);
2466 C->set_has_split_ifs(true); // Has chance for split-if optimization
2467
2468 // Null check; get casted pointer; set region slot 3
2469 Node* null_ctl = top();
2470 Node* not_null_obj = null_check_oop(subobj, &null_ctl);
2471
2472 // If not_null_obj is dead, only null-path is taken
2473 if (stopped()) { // Doing instance-of on a NULL?
2474 set_control(null_ctl);
2475 return intcon(0);
2476 }
2477 region->init_req(_null_path, null_ctl);
2478 phi ->init_req(_null_path, intcon(0)); // Set null path value
2479
2480 // Load the object's klass
2481 Node* obj_klass = load_object_klass(not_null_obj);
2482
2483 // Generate the subtype check
2484 Node* not_subtype_ctrl = gen_subtype_check(obj_klass, superklass);
2485
2486 // Plug in the success path to the general merge in slot 1.
2487 region->init_req(_obj_path, control());
2488 phi ->init_req(_obj_path, intcon(1));
2489
2490 // Plug in the failing path to the general merge in slot 2.
2491 region->init_req(_fail_path, not_subtype_ctrl);
2492 phi ->init_req(_fail_path, intcon(0));
2493
2494 // Return final merged results
2495 set_control( _gvn.transform(region) );
2496 record_for_igvn(region);
2497 return _gvn.transform(phi);
2498 }
2499
2500 //-------------------------------gen_checkcast---------------------------------
2501 // Generate a checkcast idiom. Used by both the checkcast bytecode and the
2502 // array store bytecode. Stack must be as-if BEFORE doing the bytecode so the
2503 // uncommon-trap paths work. Adjust stack after this call.
2504 // If failure_control is supplied and not null, it is filled in with
2505 // the control edge for the cast failure. Otherwise, an appropriate
2506 // uncommon trap or exception is thrown.
2507 Node* GraphKit::gen_checkcast(Node *obj, Node* superklass,
2508 Node* *failure_control) {
2509 kill_dead_locals(); // Benefit all the uncommon traps
2510 const TypeKlassPtr *tk = _gvn.type(superklass)->is_klassptr();
2511 const Type *toop = TypeOopPtr::make_from_klass(tk->klass());
2512
2513 // Fast cutout: Check the case that the cast is vacuously true.
2514 // This detects the common cases where the test will short-circuit
2515 // away completely. We do this before we perform the null check,
2516 // because if the test is going to turn into zero code, we don't
2517 // want a residual null check left around. (Causes a slowdown,
2518 // for example, in some objArray manipulations, such as a[i]=a[j].)
2519 if (tk->singleton()) {
2520 const TypeOopPtr* objtp = _gvn.type(obj)->isa_oopptr();
2521 if (objtp != NULL && objtp->klass() != NULL) {
2522 switch (static_subtype_check(tk->klass(), objtp->klass())) {
2523 case SSC_always_true:
2524 return obj;
2525 case SSC_always_false:
2526 // It needs a null check because a null will *pass* the cast check.
2527 // A non-null value will always produce an exception.
2528 return do_null_assert(obj, T_OBJECT);
2529 }
2530 }
2531 }
2532
2533 ciProfileData* data = NULL;
2534 if (failure_control == NULL) { // use MDO in regular case only
2535 assert(java_bc() == Bytecodes::_aastore ||
2536 java_bc() == Bytecodes::_checkcast,
2537 "interpreter profiles type checks only for these BCs");
2538 data = method()->method_data()->bci_to_data(bci());
2539 }
2540
2541 // Make the merge point
2542 enum { _obj_path = 1, _null_path, PATH_LIMIT };
2543 RegionNode* region = new (C, PATH_LIMIT) RegionNode(PATH_LIMIT);
2544 Node* phi = new (C, PATH_LIMIT) PhiNode(region, toop);
2545 C->set_has_split_ifs(true); // Has chance for split-if optimization
2546
2547 // Use null-cast information if it is available
2548 bool never_see_null = false;
2549 // If we see an unexpected null at a check-cast we record it and force a
2550 // recompile; the offending check-cast will be compiled to handle NULLs.
2551 // If we see several offending BCIs, then all checkcasts in the
2552 // method will be compiled to handle NULLs.
2553 if (UncommonNullCast // Cutout for this technique
2554 && failure_control == NULL // regular case
2555 && obj != null() // And not the -Xcomp stupid case?
2556 && !too_many_traps(Deoptimization::Reason_null_check)) {
2557 // Finally, check the "null_seen" bit from the interpreter.
2558 if (data == NULL || !data->as_BitData()->null_seen()) {
2559 never_see_null = true;
2560 }
2561 }
2562
2563 // Null check; get casted pointer; set region slot 3
2564 Node* null_ctl = top();
2565 Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null);
2566
2567 // If not_null_obj is dead, only null-path is taken
2568 if (stopped()) { // Doing instance-of on a NULL?
2569 set_control(null_ctl);
2570 return null();
2571 }
2572 region->init_req(_null_path, null_ctl);
2573 phi ->init_req(_null_path, null()); // Set null path value
2574
2575 Node* cast_obj = NULL; // the casted version of the object
2576
2577 // If the profile has seen exactly one type, narrow to that type.
2578 // (The subsequent subtype check will always fold up.)
2579 if (UseTypeProfile && TypeProfileCasts && data != NULL &&
2580 // Counter has never been decremented (due to cast failure).
2581 // ...This is a reasonable thing to expect. It is true of
2582 // all casts inserted by javac to implement generic types.
2583 data->as_CounterData()->count() >= 0 &&
2584 !too_many_traps(Deoptimization::Reason_class_check)) {
2585 // (No, this isn't a call, but it's enough like a virtual call
2586 // to use the same ciMethod accessor to get the profile info...)
2587 ciCallProfile profile = method()->call_profile_at_bci(bci());
2588 if (profile.count() >= 0 && // no cast failures here
2589 profile.has_receiver(0) &&
2590 profile.morphism() == 1) {
2591 ciKlass* exact_kls = profile.receiver(0);
2592 int ssc = static_subtype_check(tk->klass(), exact_kls);
2593 if (ssc == SSC_always_true) {
2594 // If we narrow the type to match what the type profile sees,
2595 // we can then remove the rest of the cast.
2596 // This is a win, even if the exact_kls is very specific,
2597 // because downstream operations, such as method calls,
2598 // will often benefit from the sharper type.
2599 Node* exact_obj = not_null_obj; // will get updated in place...
2600 Node* slow_ctl = type_check_receiver(exact_obj, exact_kls, 1.0,
2601 &exact_obj);
2602 { PreserveJVMState pjvms(this);
2603 set_control(slow_ctl);
2604 uncommon_trap(Deoptimization::Reason_class_check,
2605 Deoptimization::Action_maybe_recompile);
2606 }
2607 if (failure_control != NULL) // failure is now impossible
2608 (*failure_control) = top();
2609 replace_in_map(not_null_obj, exact_obj);
2610 // adjust the type of the phi to the exact klass:
2611 phi->raise_bottom_type(_gvn.type(exact_obj)->meet(TypePtr::NULL_PTR));
2612 cast_obj = exact_obj;
2613 }
2614 // assert(cast_obj != NULL)... except maybe the profile lied to us.
2615 }
2616 }
2617
2618 if (cast_obj == NULL) {
2619 // Load the object's klass
2620 Node* obj_klass = load_object_klass(not_null_obj);
2621
2622 // Generate the subtype check
2623 Node* not_subtype_ctrl = gen_subtype_check( obj_klass, superklass );
2624
2625 // Plug in success path into the merge
2626 cast_obj = _gvn.transform(new (C, 2) CheckCastPPNode(control(),
2627 not_null_obj, toop));
2628 // Failure path ends in uncommon trap (or may be dead - failure impossible)
2629 if (failure_control == NULL) {
2630 if (not_subtype_ctrl != top()) { // If failure is possible
2631 PreserveJVMState pjvms(this);
2632 set_control(not_subtype_ctrl);
2633 builtin_throw(Deoptimization::Reason_class_check, obj_klass);
2634 }
2635 } else {
2636 (*failure_control) = not_subtype_ctrl;
2637 }
2638 }
2639
2640 region->init_req(_obj_path, control());
2641 phi ->init_req(_obj_path, cast_obj);
2642
2643 // A merge of NULL or Casted-NotNull obj
2644 Node* res = _gvn.transform(phi);
2645
2646 // Note I do NOT always 'replace_in_map(obj,result)' here.
2647 // if( tk->klass()->can_be_primary_super() )
2648 // This means that if I successfully store an Object into an array-of-String
2649 // I 'forget' that the Object is really now known to be a String. I have to
2650 // do this because we don't have true union types for interfaces - if I store
2651 // a Baz into an array-of-Interface and then tell the optimizer it's an
2652 // Interface, I forget that it's also a Baz and cannot do Baz-like field
2653 // references to it. FIX THIS WHEN UNION TYPES APPEAR!
2654 // replace_in_map( obj, res );
2655
2656 // Return final merged results
2657 set_control( _gvn.transform(region) );
2658 record_for_igvn(region);
2659 return res;
2660 }
2661
2662 //------------------------------next_monitor-----------------------------------
2663 // What number should be given to the next monitor?
2664 int GraphKit::next_monitor() {
2665 int current = jvms()->monitor_depth()* C->sync_stack_slots();
2666 int next = current + C->sync_stack_slots();
2667 // Keep the toplevel high water mark current:
2668 if (C->fixed_slots() < next) C->set_fixed_slots(next);
2669 return current;
2670 }
2671
2672 //------------------------------insert_mem_bar---------------------------------
2673 // Memory barrier to avoid floating things around
2674 // The membar serves as a pinch point between both control and all memory slices.
2675 Node* GraphKit::insert_mem_bar(int opcode, Node* precedent) {
2676 MemBarNode* mb = MemBarNode::make(C, opcode, Compile::AliasIdxBot, precedent);
2677 mb->init_req(TypeFunc::Control, control());
2678 mb->init_req(TypeFunc::Memory, reset_memory());
2679 Node* membar = _gvn.transform(mb);
2680 set_control(_gvn.transform(new (C, 1) ProjNode(membar,TypeFunc::Control) ));
2681 set_all_memory_call(membar);
2682 return membar;
2683 }
2684
2685 //-------------------------insert_mem_bar_volatile----------------------------
2686 // Memory barrier to avoid floating things around
2687 // The membar serves as a pinch point between both control and memory(alias_idx).
2688 // If you want to make a pinch point on all memory slices, do not use this
2689 // function (even with AliasIdxBot); use insert_mem_bar() instead.
2690 Node* GraphKit::insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent) {
2691 // When Parse::do_put_xxx updates a volatile field, it appends a series
2692 // of MemBarVolatile nodes, one for *each* volatile field alias category.
2693 // The first membar is on the same memory slice as the field store opcode.
2694 // This forces the membar to follow the store. (Bug 6500685 broke this.)
2695 // All the other membars (for other volatile slices, including AliasIdxBot,
2696 // which stands for all unknown volatile slices) are control-dependent
2697 // on the first membar. This prevents later volatile loads or stores
2698 // from sliding up past the just-emitted store.
2699
2700 MemBarNode* mb = MemBarNode::make(C, opcode, alias_idx, precedent);
2701 mb->set_req(TypeFunc::Control,control());
2702 if (alias_idx == Compile::AliasIdxBot) {
2703 mb->set_req(TypeFunc::Memory, merged_memory()->base_memory());
2704 } else {
2705 assert(!(opcode == Op_Initialize && alias_idx != Compile::AliasIdxRaw), "fix caller");
2706 mb->set_req(TypeFunc::Memory, memory(alias_idx));
2707 }
2708 Node* membar = _gvn.transform(mb);
2709 set_control(_gvn.transform(new (C, 1) ProjNode(membar, TypeFunc::Control)));
2710 if (alias_idx == Compile::AliasIdxBot) {
2711 merged_memory()->set_base_memory(_gvn.transform(new (C, 1) ProjNode(membar, TypeFunc::Memory)));
2712 } else {
2713 set_memory(_gvn.transform(new (C, 1) ProjNode(membar, TypeFunc::Memory)),alias_idx);
2714 }
2715 return membar;
2716 }
2717
2718 //------------------------------shared_lock------------------------------------
2719 // Emit locking code.
2720 FastLockNode* GraphKit::shared_lock(Node* obj) {
2721 // bci is either a monitorenter bc or InvocationEntryBci
2722 // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
2723 assert(SynchronizationEntryBCI == InvocationEntryBci, "");
2724
2725 if( !GenerateSynchronizationCode )
2726 return NULL; // Not locking things?
2727 if (stopped()) // Dead monitor?
2728 return NULL;
2729
2730 assert(dead_locals_are_killed(), "should kill locals before sync. point");
2731
2732 // Box the stack location
2733 Node* box = _gvn.transform(new (C, 1) BoxLockNode(next_monitor()));
2734 Node* mem = reset_memory();
2735
2736 FastLockNode * flock = _gvn.transform(new (C, 3) FastLockNode(0, obj, box) )->as_FastLock();
2737 if (PrintPreciseBiasedLockingStatistics) {
2738 // Create the counters for this fast lock.
2739 flock->create_lock_counter(sync_jvms()); // sync_jvms used to get current bci
2740 }
2741 // Add monitor to debug info for the slow path. If we block inside the
2742 // slow path and de-opt, we need the monitor hanging around
2743 map()->push_monitor( flock );
2744
2745 const TypeFunc *tf = LockNode::lock_type();
2746 LockNode *lock = new (C, tf->domain()->cnt()) LockNode(C, tf);
2747
2748 lock->init_req( TypeFunc::Control, control() );
2749 lock->init_req( TypeFunc::Memory , mem );
2750 lock->init_req( TypeFunc::I_O , top() ) ; // does no i/o
2751 lock->init_req( TypeFunc::FramePtr, frameptr() );
2752 lock->init_req( TypeFunc::ReturnAdr, top() );
2753
2754 lock->init_req(TypeFunc::Parms + 0, obj);
2755 lock->init_req(TypeFunc::Parms + 1, box);
2756 lock->init_req(TypeFunc::Parms + 2, flock);
2757 add_safepoint_edges(lock);
2758
2759 lock = _gvn.transform( lock )->as_Lock();
2760
2761 // lock has no side-effects, sets few values
2762 set_predefined_output_for_runtime_call(lock, mem, TypeRawPtr::BOTTOM);
2763
2764 insert_mem_bar(Op_MemBarAcquire);
2765
2766 // Add this to the worklist so that the lock can be eliminated
2767 record_for_igvn(lock);
2768
2769 #ifndef PRODUCT
2770 if (PrintLockStatistics) {
2771 // Update the counter for this lock. Don't bother using an atomic
2772 // operation since we don't require absolute accuracy.
2773 lock->create_lock_counter(map()->jvms());
2774 int adr_type = Compile::AliasIdxRaw;
2775 Node* counter_addr = makecon(TypeRawPtr::make(lock->counter()->addr()));
2776 Node* cnt = make_load(NULL, counter_addr, TypeInt::INT, T_INT, adr_type);
2777 Node* incr = _gvn.transform(new (C, 3) AddINode(cnt, _gvn.intcon(1)));
2778 store_to_memory(control(), counter_addr, incr, T_INT, adr_type);
2779 }
2780 #endif
2781
2782 return flock;
2783 }
2784
2785
2786 //------------------------------shared_unlock----------------------------------
2787 // Emit unlocking code.
2788 void GraphKit::shared_unlock(Node* box, Node* obj) {
2789 // bci is either a monitorenter bc or InvocationEntryBci
2790 // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
2791 assert(SynchronizationEntryBCI == InvocationEntryBci, "");
2792
2793 if( !GenerateSynchronizationCode )
2794 return;
2795 if (stopped()) { // Dead monitor?
2796 map()->pop_monitor(); // Kill monitor from debug info
2797 return;
2798 }
2799
2800 // Memory barrier to avoid floating things down past the locked region
2801 insert_mem_bar(Op_MemBarRelease);
2802
2803 const TypeFunc *tf = OptoRuntime::complete_monitor_exit_Type();
2804 UnlockNode *unlock = new (C, tf->domain()->cnt()) UnlockNode(C, tf);
2805 uint raw_idx = Compile::AliasIdxRaw;
2806 unlock->init_req( TypeFunc::Control, control() );
2807 unlock->init_req( TypeFunc::Memory , memory(raw_idx) );
2808 unlock->init_req( TypeFunc::I_O , top() ) ; // does no i/o
2809 unlock->init_req( TypeFunc::FramePtr, frameptr() );
2810 unlock->init_req( TypeFunc::ReturnAdr, top() );
2811
2812 unlock->init_req(TypeFunc::Parms + 0, obj);
2813 unlock->init_req(TypeFunc::Parms + 1, box);
2814 unlock = _gvn.transform(unlock)->as_Unlock();
2815
2816 Node* mem = reset_memory();
2817
2818 // unlock has no side-effects, sets few values
2819 set_predefined_output_for_runtime_call(unlock, mem, TypeRawPtr::BOTTOM);
2820
2821 // Kill monitor from debug info
2822 map()->pop_monitor( );
2823 }
2824
2825 //-------------------------------get_layout_helper-----------------------------
2826 // If the given klass is a constant or known to be an array,
2827 // fetch the constant layout helper value into constant_value
2828 // and return (Node*)NULL. Otherwise, load the non-constant
2829 // layout helper value, and return the node which represents it.
2830 // This two-faced routine is useful because allocation sites
2831 // almost always feature constant types.
2832 Node* GraphKit::get_layout_helper(Node* klass_node, jint& constant_value) {
2833 const TypeKlassPtr* inst_klass = _gvn.type(klass_node)->isa_klassptr();
2834 if (!StressReflectiveCode && inst_klass != NULL) {
2835 ciKlass* klass = inst_klass->klass();
2836 bool xklass = inst_klass->klass_is_exact();
2837 if (xklass || klass->is_array_klass()) {
2838 jint lhelper = klass->layout_helper();
2839 if (lhelper != Klass::_lh_neutral_value) {
2840 constant_value = lhelper;
2841 return (Node*) NULL;
2842 }
2843 }
2844 }
2845 constant_value = Klass::_lh_neutral_value; // put in a known value
2846 Node* lhp = basic_plus_adr(klass_node, klass_node, Klass::layout_helper_offset_in_bytes() + sizeof(oopDesc));
2847 return make_load(NULL, lhp, TypeInt::INT, T_INT);
2848 }
2849
2850 // We just put in an allocate/initialize with a big raw-memory effect.
2851 // Hook selected additional alias categories on the initialization.
2852 static void hook_memory_on_init(GraphKit& kit, int alias_idx,
2853 MergeMemNode* init_in_merge,
2854 Node* init_out_raw) {
2855 DEBUG_ONLY(Node* init_in_raw = init_in_merge->base_memory());
2856 assert(init_in_merge->memory_at(alias_idx) == init_in_raw, "");
2857
2858 Node* prevmem = kit.memory(alias_idx);
2859 init_in_merge->set_memory_at(alias_idx, prevmem);
2860 kit.set_memory(init_out_raw, alias_idx);
2861 }
2862
2863 //---------------------------set_output_for_allocation-------------------------
2864 Node* GraphKit::set_output_for_allocation(AllocateNode* alloc,
2865 const TypeOopPtr* oop_type,
2866 bool raw_mem_only) {
2867 int rawidx = Compile::AliasIdxRaw;
2868 alloc->set_req( TypeFunc::FramePtr, frameptr() );
2869 add_safepoint_edges(alloc);
2870 Node* allocx = _gvn.transform(alloc);
2871 set_control( _gvn.transform(new (C, 1) ProjNode(allocx, TypeFunc::Control) ) );
2872 // create memory projection for i_o
2873 set_memory ( _gvn.transform( new (C, 1) ProjNode(allocx, TypeFunc::Memory, true) ), rawidx );
2874 make_slow_call_ex(allocx, env()->OutOfMemoryError_klass(), true);
2875
2876 // create a memory projection as for the normal control path
2877 Node* malloc = _gvn.transform(new (C, 1) ProjNode(allocx, TypeFunc::Memory));
2878 set_memory(malloc, rawidx);
2879
2880 // a normal slow-call doesn't change i_o, but an allocation does
2881 // we create a separate i_o projection for the normal control path
2882 set_i_o(_gvn.transform( new (C, 1) ProjNode(allocx, TypeFunc::I_O, false) ) );
2883 Node* rawoop = _gvn.transform( new (C, 1) ProjNode(allocx, TypeFunc::Parms) );
2884
2885 // put in an initialization barrier
2886 InitializeNode* init = insert_mem_bar_volatile(Op_Initialize, rawidx,
2887 rawoop)->as_Initialize();
2888 assert(alloc->initialization() == init, "2-way macro link must work");
2889 assert(init ->allocation() == alloc, "2-way macro link must work");
2890 if (ReduceFieldZeroing && !raw_mem_only) {
2891 // Extract memory strands which may participate in the new object's
2892 // initialization, and source them from the new InitializeNode.
2893 // This will allow us to observe initializations when they occur,
2894 // and link them properly (as a group) to the InitializeNode.
2895 assert(init->in(InitializeNode::Memory) == malloc, "");
2896 MergeMemNode* minit_in = MergeMemNode::make(C, malloc);
2897 init->set_req(InitializeNode::Memory, minit_in);
2898 record_for_igvn(minit_in); // fold it up later, if possible
2899 Node* minit_out = memory(rawidx);
2900 assert(minit_out->is_Proj() && minit_out->in(0) == init, "");
2901 if (oop_type->isa_aryptr()) {
2902 const TypePtr* telemref = oop_type->add_offset(Type::OffsetBot);
2903 int elemidx = C->get_alias_index(telemref);
2904 hook_memory_on_init(*this, elemidx, minit_in, minit_out);
2905 } else if (oop_type->isa_instptr()) {
2906 ciInstanceKlass* ik = oop_type->klass()->as_instance_klass();
2907 for (int i = 0, len = ik->nof_nonstatic_fields(); i < len; i++) {
2908 ciField* field = ik->nonstatic_field_at(i);
2909 if (field->offset() >= TrackedInitializationLimit * HeapWordSize)
2910 continue; // do not bother to track really large numbers of fields
2911 // Find (or create) the alias category for this field:
2912 int fieldidx = C->alias_type(field)->index();
2913 hook_memory_on_init(*this, fieldidx, minit_in, minit_out);
2914 }
2915 }
2916 }
2917
2918 // Cast raw oop to the real thing...
2919 Node* javaoop = new (C, 2) CheckCastPPNode(control(), rawoop, oop_type);
2920 javaoop = _gvn.transform(javaoop);
2921 C->set_recent_alloc(control(), javaoop);
2922 assert(just_allocated_object(control()) == javaoop, "just allocated");
2923
2924 #ifdef ASSERT
2925 { // Verify that the AllocateNode::Ideal_allocation recognizers work:
2926 assert(AllocateNode::Ideal_allocation(rawoop, &_gvn) == alloc,
2927 "Ideal_allocation works");
2928 assert(AllocateNode::Ideal_allocation(javaoop, &_gvn) == alloc,
2929 "Ideal_allocation works");
2930 if (alloc->is_AllocateArray()) {
2931 assert(AllocateArrayNode::Ideal_array_allocation(rawoop, &_gvn) == alloc->as_AllocateArray(),
2932 "Ideal_allocation works");
2933 assert(AllocateArrayNode::Ideal_array_allocation(javaoop, &_gvn) == alloc->as_AllocateArray(),
2934 "Ideal_allocation works");
2935 } else {
2936 assert(alloc->in(AllocateNode::ALength)->is_top(), "no length, please");
2937 }
2938 }
2939 #endif //ASSERT
2940
2941 return javaoop;
2942 }
2943
2944 //---------------------------new_instance--------------------------------------
2945 // This routine takes a klass_node which may be constant (for a static type)
2946 // or may be non-constant (for reflective code). It will work equally well
2947 // for either, and the graph will fold nicely if the optimizer later reduces
2948 // the type to a constant.
2949 // The optional arguments are for specialized use by intrinsics:
2950 // - If 'extra_slow_test' if not null is an extra condition for the slow-path.
2951 // - If 'raw_mem_only', do not cast the result to an oop.
2952 // - If 'return_size_val', report the the total object size to the caller.
2953 Node* GraphKit::new_instance(Node* klass_node,
2954 Node* extra_slow_test,
2955 bool raw_mem_only, // affect only raw memory
2956 Node* *return_size_val) {
2957 // Compute size in doublewords
2958 // The size is always an integral number of doublewords, represented
2959 // as a positive bytewise size stored in the klass's layout_helper.
2960 // The layout_helper also encodes (in a low bit) the need for a slow path.
2961 jint layout_con = Klass::_lh_neutral_value;
2962 Node* layout_val = get_layout_helper(klass_node, layout_con);
2963 int layout_is_con = (layout_val == NULL);
2964
2965 if (extra_slow_test == NULL) extra_slow_test = intcon(0);
2966 // Generate the initial go-slow test. It's either ALWAYS (return a
2967 // Node for 1) or NEVER (return a NULL) or perhaps (in the reflective
2968 // case) a computed value derived from the layout_helper.
2969 Node* initial_slow_test = NULL;
2970 if (layout_is_con) {
2971 assert(!StressReflectiveCode, "stress mode does not use these paths");
2972 bool must_go_slow = Klass::layout_helper_needs_slow_path(layout_con);
2973 initial_slow_test = must_go_slow? intcon(1): extra_slow_test;
2974
2975 } else { // reflective case
2976 // This reflective path is used by Unsafe.allocateInstance.
2977 // (It may be stress-tested by specifying StressReflectiveCode.)
2978 // Basically, we want to get into the VM is there's an illegal argument.
2979 Node* bit = intcon(Klass::_lh_instance_slow_path_bit);
2980 initial_slow_test = _gvn.transform( new (C, 3) AndINode(layout_val, bit) );
2981 if (extra_slow_test != intcon(0)) {
2982 initial_slow_test = _gvn.transform( new (C, 3) OrINode(initial_slow_test, extra_slow_test) );
2983 }
2984 // (Macro-expander will further convert this to a Bool, if necessary.)
2985 }
2986
2987 // Find the size in bytes. This is easy; it's the layout_helper.
2988 // The size value must be valid even if the slow path is taken.
2989 Node* size = NULL;
2990 if (layout_is_con) {
2991 size = MakeConX(Klass::layout_helper_size_in_bytes(layout_con));
2992 } else { // reflective case
2993 // This reflective path is used by clone and Unsafe.allocateInstance.
2994 size = ConvI2X(layout_val);
2995
2996 // Clear the low bits to extract layout_helper_size_in_bytes:
2997 assert((int)Klass::_lh_instance_slow_path_bit < BytesPerLong, "clear bit");
2998 Node* mask = MakeConX(~ (intptr_t)right_n_bits(LogBytesPerLong));
2999 size = _gvn.transform( new (C, 3) AndXNode(size, mask) );
3000 }
3001 if (return_size_val != NULL) {
3002 (*return_size_val) = size;
3003 }
3004
3005 // This is a precise notnull oop of the klass.
3006 // (Actually, it need not be precise if this is a reflective allocation.)
3007 // It's what we cast the result to.
3008 const TypeKlassPtr* tklass = _gvn.type(klass_node)->isa_klassptr();
3009 if (!tklass) tklass = TypeKlassPtr::OBJECT;
3010 const TypeOopPtr* oop_type = tklass->as_instance_type();
3011
3012 // Now generate allocation code
3013
3014 // The entire memory state is needed for slow path of the allocation
3015 // since GC and deoptimization can happened.
3016 Node *mem = reset_memory();
3017 set_all_memory(mem); // Create new memory state
3018
3019 AllocateNode* alloc
3020 = new (C, AllocateNode::ParmLimit)
3021 AllocateNode(C, AllocateNode::alloc_type(),
3022 control(), mem, i_o(),
3023 size, klass_node,
3024 initial_slow_test);
3025
3026 return set_output_for_allocation(alloc, oop_type, raw_mem_only);
3027 }
3028
3029 //-------------------------------new_array-------------------------------------
3030 // helper for both newarray and anewarray
3031 // The 'length' parameter is (obviously) the length of the array.
3032 // See comments on new_instance for the meaning of the other arguments.
3033 Node* GraphKit::new_array(Node* klass_node, // array klass (maybe variable)
3034 Node* length, // number of array elements
3035 int nargs, // number of arguments to push back for uncommon trap
3036 bool raw_mem_only, // affect only raw memory
3037 Node* *return_size_val) {
3038 jint layout_con = Klass::_lh_neutral_value;
3039 Node* layout_val = get_layout_helper(klass_node, layout_con);
3040 int layout_is_con = (layout_val == NULL);
3041
3042 if (!layout_is_con && !StressReflectiveCode &&
3043 !too_many_traps(Deoptimization::Reason_class_check)) {
3044 // This is a reflective array creation site.
3045 // Optimistically assume that it is a subtype of Object[],
3046 // so that we can fold up all the address arithmetic.
3047 layout_con = Klass::array_layout_helper(T_OBJECT);
3048 Node* cmp_lh = _gvn.transform( new(C, 3) CmpINode(layout_val, intcon(layout_con)) );
3049 Node* bol_lh = _gvn.transform( new(C, 2) BoolNode(cmp_lh, BoolTest::eq) );
3050 { BuildCutout unless(this, bol_lh, PROB_MAX);
3051 _sp += nargs;
3052 uncommon_trap(Deoptimization::Reason_class_check,
3053 Deoptimization::Action_maybe_recompile);
3054 }
3055 layout_val = NULL;
3056 layout_is_con = true;
3057 }
3058
3059 // Generate the initial go-slow test. Make sure we do not overflow
3060 // if length is huge (near 2Gig) or negative! We do not need
3061 // exact double-words here, just a close approximation of needed
3062 // double-words. We can't add any offset or rounding bits, lest we
3063 // take a size -1 of bytes and make it positive. Use an unsigned
3064 // compare, so negative sizes look hugely positive.
3065 int fast_size_limit = FastAllocateSizeLimit;
3066 if (layout_is_con) {
3067 assert(!StressReflectiveCode, "stress mode does not use these paths");
3068 // Increase the size limit if we have exact knowledge of array type.
3069 int log2_esize = Klass::layout_helper_log2_element_size(layout_con);
3070 fast_size_limit <<= (LogBytesPerLong - log2_esize);
3071 }
3072
3073 Node* initial_slow_cmp = _gvn.transform( new (C, 3) CmpUNode( length, intcon( fast_size_limit ) ) );
3074 Node* initial_slow_test = _gvn.transform( new (C, 2) BoolNode( initial_slow_cmp, BoolTest::gt ) );
3075 if (initial_slow_test->is_Bool()) {
3076 // Hide it behind a CMoveI, or else PhaseIdealLoop::split_up will get sick.
3077 initial_slow_test = initial_slow_test->as_Bool()->as_int_value(&_gvn);
3078 }
3079
3080 // --- Size Computation ---
3081 // array_size = round_to_heap(array_header + (length << elem_shift));
3082 // where round_to_heap(x) == round_to(x, MinObjAlignmentInBytes)
3083 // and round_to(x, y) == ((x + y-1) & ~(y-1))
3084 // The rounding mask is strength-reduced, if possible.
3085 int round_mask = MinObjAlignmentInBytes - 1;
3086 Node* header_size = NULL;
3087 int header_size_min = arrayOopDesc::base_offset_in_bytes(T_BYTE);
3088 // (T_BYTE has the weakest alignment and size restrictions...)
3089 if (layout_is_con) {
3090 int hsize = Klass::layout_helper_header_size(layout_con);
3091 int eshift = Klass::layout_helper_log2_element_size(layout_con);
3092 BasicType etype = Klass::layout_helper_element_type(layout_con);
3093 if ((round_mask & ~right_n_bits(eshift)) == 0)
3094 round_mask = 0; // strength-reduce it if it goes away completely
3095 assert((hsize & right_n_bits(eshift)) == 0, "hsize is pre-rounded");
3096 assert(header_size_min <= hsize, "generic minimum is smallest");
3097 header_size_min = hsize;
3098 header_size = intcon(hsize + round_mask);
3099 } else {
3100 Node* hss = intcon(Klass::_lh_header_size_shift);
3101 Node* hsm = intcon(Klass::_lh_header_size_mask);
3102 Node* hsize = _gvn.transform( new(C, 3) URShiftINode(layout_val, hss) );
3103 hsize = _gvn.transform( new(C, 3) AndINode(hsize, hsm) );
3104 Node* mask = intcon(round_mask);
3105 header_size = _gvn.transform( new(C, 3) AddINode(hsize, mask) );
3106 }
3107
3108 Node* elem_shift = NULL;
3109 if (layout_is_con) {
3110 int eshift = Klass::layout_helper_log2_element_size(layout_con);
3111 if (eshift != 0)
3112 elem_shift = intcon(eshift);
3113 } else {
3114 // There is no need to mask or shift this value.
3115 // The semantics of LShiftINode include an implicit mask to 0x1F.
3116 assert(Klass::_lh_log2_element_size_shift == 0, "use shift in place");
3117 elem_shift = layout_val;
3118 }
3119
3120 // Transition to native address size for all offset calculations:
3121 Node* lengthx = ConvI2X(length);
3122 Node* headerx = ConvI2X(header_size);
3123 #ifdef _LP64
3124 { const TypeLong* tllen = _gvn.find_long_type(lengthx);
3125 if (tllen != NULL && tllen->_lo < 0) {
3126 // Add a manual constraint to a positive range. Cf. array_element_address.
3127 jlong size_max = arrayOopDesc::max_array_length(T_BYTE);
3128 if (size_max > tllen->_hi) size_max = tllen->_hi;
3129 const TypeLong* tlcon = TypeLong::make(CONST64(0), size_max, Type::WidenMin);
3130 lengthx = _gvn.transform( new (C, 2) ConvI2LNode(length, tlcon));
3131 }
3132 }
3133 #endif
3134
3135 // Combine header size (plus rounding) and body size. Then round down.
3136 // This computation cannot overflow, because it is used only in two
3137 // places, one where the length is sharply limited, and the other
3138 // after a successful allocation.
3139 Node* abody = lengthx;
3140 if (elem_shift != NULL)
3141 abody = _gvn.transform( new(C, 3) LShiftXNode(lengthx, elem_shift) );
3142 Node* size = _gvn.transform( new(C, 3) AddXNode(headerx, abody) );
3143 if (round_mask != 0) {
3144 Node* mask = MakeConX(~round_mask);
3145 size = _gvn.transform( new(C, 3) AndXNode(size, mask) );
3146 }
3147 // else if round_mask == 0, the size computation is self-rounding
3148
3149 if (return_size_val != NULL) {
3150 // This is the size
3151 (*return_size_val) = size;
3152 }
3153
3154 // Now generate allocation code
3155
3156 // The entire memory state is needed for slow path of the allocation
3157 // since GC and deoptimization can happened.
3158 Node *mem = reset_memory();
3159 set_all_memory(mem); // Create new memory state
3160
3161 // Create the AllocateArrayNode and its result projections
3162 AllocateArrayNode* alloc
3163 = new (C, AllocateArrayNode::ParmLimit)
3164 AllocateArrayNode(C, AllocateArrayNode::alloc_type(),
3165 control(), mem, i_o(),
3166 size, klass_node,
3167 initial_slow_test,
3168 length);
3169
3170 // Cast to correct type. Note that the klass_node may be constant or not,
3171 // and in the latter case the actual array type will be inexact also.
3172 // (This happens via a non-constant argument to inline_native_newArray.)
3173 // In any case, the value of klass_node provides the desired array type.
3174 const TypeInt* length_type = _gvn.find_int_type(length);
3175 const TypeOopPtr* ary_type = _gvn.type(klass_node)->is_klassptr()->as_instance_type();
3176 if (ary_type->isa_aryptr() && length_type != NULL) {
3177 // Try to get a better type than POS for the size
3178 ary_type = ary_type->is_aryptr()->cast_to_size(length_type);
3179 }
3180
3181 Node* javaoop = set_output_for_allocation(alloc, ary_type, raw_mem_only);
3182
3183 // Cast length on remaining path to be as narrow as possible
3184 if (map()->find_edge(length) >= 0) {
3185 Node* ccast = alloc->make_ideal_length(ary_type, &_gvn);
3186 if (ccast != length) {
3187 _gvn.set_type_bottom(ccast);
3188 record_for_igvn(ccast);
3189 replace_in_map(length, ccast);
3190 }
3191 }
3192
3193 return javaoop;
3194 }
3195
3196 // The following "Ideal_foo" functions are placed here because they recognize
3197 // the graph shapes created by the functions immediately above.
3198
3199 //---------------------------Ideal_allocation----------------------------------
3200 // Given an oop pointer or raw pointer, see if it feeds from an AllocateNode.
3201 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase) {
3202 if (ptr == NULL) { // reduce dumb test in callers
3203 return NULL;
3204 }
3205 if (ptr->is_CheckCastPP()) { // strip a raw-to-oop cast
3206 ptr = ptr->in(1);
3207 if (ptr == NULL) return NULL;
3208 }
3209 if (ptr->is_Proj()) {
3210 Node* allo = ptr->in(0);
3211 if (allo != NULL && allo->is_Allocate()) {
3212 return allo->as_Allocate();
3213 }
3214 }
3215 // Report failure to match.
3216 return NULL;
3217 }
3218
3219 // Fancy version which also strips off an offset (and reports it to caller).
3220 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase,
3221 intptr_t& offset) {
3222 Node* base = AddPNode::Ideal_base_and_offset(ptr, phase, offset);
3223 if (base == NULL) return NULL;
3224 return Ideal_allocation(base, phase);
3225 }
3226
3227 // Trace Initialize <- Proj[Parm] <- Allocate
3228 AllocateNode* InitializeNode::allocation() {
3229 Node* rawoop = in(InitializeNode::RawAddress);
3230 if (rawoop->is_Proj()) {
3231 Node* alloc = rawoop->in(0);
3232 if (alloc->is_Allocate()) {
3233 return alloc->as_Allocate();
3234 }
3235 }
3236 return NULL;
3237 }
3238
3239 // Trace Allocate -> Proj[Parm] -> Initialize
3240 InitializeNode* AllocateNode::initialization() {
3241 ProjNode* rawoop = proj_out(AllocateNode::RawAddress);
3242 if (rawoop == NULL) return NULL;
3243 for (DUIterator_Fast imax, i = rawoop->fast_outs(imax); i < imax; i++) {
3244 Node* init = rawoop->fast_out(i);
3245 if (init->is_Initialize()) {
3246 assert(init->as_Initialize()->allocation() == this, "2-way link");
3247 return init->as_Initialize();
3248 }
3249 }
3250 return NULL;
3251 }
3252
3253 //----------------------------- store barriers ----------------------------
3254 #define __ ideal.
3255
3256 void GraphKit::sync_kit(IdealKit& ideal) {
3257 // Final sync IdealKit and graphKit.
3258 __ drain_delay_transform();
3259 set_all_memory(__ merged_memory());
3260 set_control(__ ctrl());
3261 }
3262
3263 // vanilla/CMS post barrier
3264 // Insert a write-barrier store. This is to let generational GC work; we have
3265 // to flag all oop-stores before the next GC point.
3266 void GraphKit::write_barrier_post(Node* oop_store,
3267 Node* obj,
3268 Node* adr,
3269 uint adr_idx,
3270 Node* val,
3271 bool use_precise) {
3272 // No store check needed if we're storing a NULL or an old object
3273 // (latter case is probably a string constant). The concurrent
3274 // mark sweep garbage collector, however, needs to have all nonNull
3275 // oop updates flagged via card-marks.
3276 if (val != NULL && val->is_Con()) {
3277 // must be either an oop or NULL
3278 const Type* t = val->bottom_type();
3279 if (t == TypePtr::NULL_PTR || t == Type::TOP)
3280 // stores of null never (?) need barriers
3281 return;
3282 ciObject* con = t->is_oopptr()->const_oop();
3283 if (con != NULL
3284 && con->is_perm()
3285 && Universe::heap()->can_elide_permanent_oop_store_barriers())
3286 // no store barrier needed, because no old-to-new ref created
3287 return;
3288 }
3289
3290 if (use_ReduceInitialCardMarks()
3291 && obj == just_allocated_object(control())) {
3292 // We can skip marks on a freshly-allocated object in Eden.
3293 // Keep this code in sync with maybe_defer_card_mark() in runtime.cpp.
3294 // That routine informs GC to take appropriate compensating steps
3295 // so as to make this card-mark elision safe.
3296 return;
3297 }
3298
3299 if (!use_precise) {
3300 // All card marks for a (non-array) instance are in one place:
3301 adr = obj;
3302 }
3303 // (Else it's an array (or unknown), and we want more precise card marks.)
3304 assert(adr != NULL, "");
3305
3306 IdealKit ideal(gvn(), control(), merged_memory(), true);
3307
3308 // Convert the pointer to an int prior to doing math on it
3309 Node* cast = __ CastPX(__ ctrl(), adr);
3310
3311 // Divide by card size
3312 assert(Universe::heap()->barrier_set()->kind() == BarrierSet::CardTableModRef,
3313 "Only one we handle so far.");
3314 Node* card_offset = __ URShiftX( cast, __ ConI(CardTableModRefBS::card_shift) );
3315
3316 // Combine card table base and card offset
3317 Node* card_adr = __ AddP(__ top(), byte_map_base_node(), card_offset );
3318
3319 // Get the alias_index for raw card-mark memory
3320 int adr_type = Compile::AliasIdxRaw;
3321 // Smash zero into card
3322 Node* zero = __ ConI(0);
3323 BasicType bt = T_BYTE;
3324 if( !UseConcMarkSweepGC ) {
3325 __ store(__ ctrl(), card_adr, zero, bt, adr_type);
3326 } else {
3327 // Specialized path for CM store barrier
3328 __ storeCM(__ ctrl(), card_adr, zero, oop_store, adr_idx, bt, adr_type);
3329 }
3330
3331 // Final sync IdealKit and GraphKit.
3332 sync_kit(ideal);
3333 }
3334
3335 // G1 pre/post barriers
3336 void GraphKit::g1_write_barrier_pre(Node* obj,
3337 Node* adr,
3338 uint alias_idx,
3339 Node* val,
3340 const TypeOopPtr* val_type,
3341 BasicType bt) {
3342 IdealKit ideal(gvn(), control(), merged_memory(), true);
3343
3344 Node* tls = __ thread(); // ThreadLocalStorage
3345
3346 Node* no_ctrl = NULL;
3347 Node* no_base = __ top();
3348 Node* zero = __ ConI(0);
3349
3350 float likely = PROB_LIKELY(0.999);
3351 float unlikely = PROB_UNLIKELY(0.999);
3352
3353 BasicType active_type = in_bytes(PtrQueue::byte_width_of_active()) == 4 ? T_INT : T_BYTE;
3354 assert(in_bytes(PtrQueue::byte_width_of_active()) == 4 || in_bytes(PtrQueue::byte_width_of_active()) == 1, "flag width");
3355
3356 // Offsets into the thread
3357 const int marking_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 648
3358 PtrQueue::byte_offset_of_active());
3359 const int index_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 656
3360 PtrQueue::byte_offset_of_index());
3361 const int buffer_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 652
3362 PtrQueue::byte_offset_of_buf());
3363 // Now the actual pointers into the thread
3364
3365 // set_control( ctl);
3366
3367 Node* marking_adr = __ AddP(no_base, tls, __ ConX(marking_offset));
3368 Node* buffer_adr = __ AddP(no_base, tls, __ ConX(buffer_offset));
3369 Node* index_adr = __ AddP(no_base, tls, __ ConX(index_offset));
3370
3371 // Now some of the values
3372
3373 Node* marking = __ load(__ ctrl(), marking_adr, TypeInt::INT, active_type, Compile::AliasIdxRaw);
3374
3375 // if (!marking)
3376 __ if_then(marking, BoolTest::ne, zero); {
3377 Node* index = __ load(__ ctrl(), index_adr, TypeInt::INT, T_INT, Compile::AliasIdxRaw);
3378
3379 const Type* t1 = adr->bottom_type();
3380 const Type* t2 = val->bottom_type();
3381
3382 Node* orig = __ load(no_ctrl, adr, val_type, bt, alias_idx);
3383 // if (orig != NULL)
3384 __ if_then(orig, BoolTest::ne, null()); {
3385 Node* buffer = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw);
3386
3387 // load original value
3388 // alias_idx correct??
3389
3390 // is the queue for this thread full?
3391 __ if_then(index, BoolTest::ne, zero, likely); {
3392
3393 // decrement the index
3394 Node* next_index = __ SubI(index, __ ConI(sizeof(intptr_t)));
3395 Node* next_indexX = next_index;
3396 #ifdef _LP64
3397 // We could refine the type for what it's worth
3398 // const TypeLong* lidxtype = TypeLong::make(CONST64(0), get_size_from_queue);
3399 next_indexX = _gvn.transform( new (C, 2) ConvI2LNode(next_index, TypeLong::make(0, max_jlong, Type::WidenMax)) );
3400 #endif
3401
3402 // Now get the buffer location we will log the original value into and store it
3403 Node *log_addr = __ AddP(no_base, buffer, next_indexX);
3404 __ store(__ ctrl(), log_addr, orig, T_OBJECT, Compile::AliasIdxRaw);
3405
3406 // update the index
3407 __ store(__ ctrl(), index_adr, next_index, T_INT, Compile::AliasIdxRaw);
3408
3409 } __ else_(); {
3410
3411 // logging buffer is full, call the runtime
3412 const TypeFunc *tf = OptoRuntime::g1_wb_pre_Type();
3413 __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_pre), "g1_wb_pre", orig, tls);
3414 } __ end_if(); // (!index)
3415 } __ end_if(); // (orig != NULL)
3416 } __ end_if(); // (!marking)
3417
3418 // Final sync IdealKit and GraphKit.
3419 sync_kit(ideal);
3420 }
3421
3422 //
3423 // Update the card table and add card address to the queue
3424 //
3425 void GraphKit::g1_mark_card(IdealKit& ideal,
3426 Node* card_adr,
3427 Node* oop_store,
3428 uint oop_alias_idx,
3429 Node* index,
3430 Node* index_adr,
3431 Node* buffer,
3432 const TypeFunc* tf) {
3433
3434 Node* zero = __ ConI(0);
3435 Node* no_base = __ top();
3436 BasicType card_bt = T_BYTE;
3437 // Smash zero into card. MUST BE ORDERED WRT TO STORE
3438 __ storeCM(__ ctrl(), card_adr, zero, oop_store, oop_alias_idx, card_bt, Compile::AliasIdxRaw);
3439
3440 // Now do the queue work
3441 __ if_then(index, BoolTest::ne, zero); {
3442
3443 Node* next_index = __ SubI(index, __ ConI(sizeof(intptr_t)));
3444 Node* next_indexX = next_index;
3445 #ifdef _LP64
3446 // We could refine the type for what it's worth
3447 // const TypeLong* lidxtype = TypeLong::make(CONST64(0), get_size_from_queue);
3448 next_indexX = _gvn.transform( new (C, 2) ConvI2LNode(next_index, TypeLong::make(0, max_jlong, Type::WidenMax)) );
3449 #endif // _LP64
3450 Node* log_addr = __ AddP(no_base, buffer, next_indexX);
3451
3452 __ store(__ ctrl(), log_addr, card_adr, T_ADDRESS, Compile::AliasIdxRaw);
3453 __ store(__ ctrl(), index_adr, next_index, T_INT, Compile::AliasIdxRaw);
3454
3455 } __ else_(); {
3456 __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_post), "g1_wb_post", card_adr, __ thread());
3457 } __ end_if();
3458
3459 }
3460
3461 void GraphKit::g1_write_barrier_post(Node* oop_store,
3462 Node* obj,
3463 Node* adr,
3464 uint alias_idx,
3465 Node* val,
3466 BasicType bt,
3467 bool use_precise) {
3468 // If we are writing a NULL then we need no post barrier
3469
3470 if (val != NULL && val->is_Con() && val->bottom_type() == TypePtr::NULL_PTR) {
3471 // Must be NULL
3472 const Type* t = val->bottom_type();
3473 assert(t == Type::TOP || t == TypePtr::NULL_PTR, "must be NULL");
3474 // No post barrier if writing NULLx
3475 return;
3476 }
3477
3478 if (!use_precise) {
3479 // All card marks for a (non-array) instance are in one place:
3480 adr = obj;
3481 }
3482 // (Else it's an array (or unknown), and we want more precise card marks.)
3483 assert(adr != NULL, "");
3484
3485 IdealKit ideal(gvn(), control(), merged_memory(), true);
3486
3487 Node* tls = __ thread(); // ThreadLocalStorage
3488
3489 Node* no_ctrl = NULL;
3490 Node* no_base = __ top();
3491 float likely = PROB_LIKELY(0.999);
3492 float unlikely = PROB_UNLIKELY(0.999);
3493 Node* zero = __ ConI(0);
3494 Node* zeroX = __ ConX(0);
3495
3496 // Get the alias_index for raw card-mark memory
3497 const TypePtr* card_type = TypeRawPtr::BOTTOM;
3498
3499 const TypeFunc *tf = OptoRuntime::g1_wb_post_Type();
3500
3501 // Offsets into the thread
3502 const int index_offset = in_bytes(JavaThread::dirty_card_queue_offset() +
3503 PtrQueue::byte_offset_of_index());
3504 const int buffer_offset = in_bytes(JavaThread::dirty_card_queue_offset() +
3505 PtrQueue::byte_offset_of_buf());
3506
3507 // Pointers into the thread
3508
3509 Node* buffer_adr = __ AddP(no_base, tls, __ ConX(buffer_offset));
3510 Node* index_adr = __ AddP(no_base, tls, __ ConX(index_offset));
3511
3512 // Now some values
3513
3514 Node* index = __ load(no_ctrl, index_adr, TypeInt::INT, T_INT, Compile::AliasIdxRaw);
3515 Node* buffer = __ load(no_ctrl, buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw);
3516
3517
3518 // Convert the store obj pointer to an int prior to doing math on it
3519 // Must use ctrl to prevent "integerized oop" existing across safepoint
3520 Node* cast = __ CastPX(__ ctrl(), adr);
3521
3522 // Divide pointer by card size
3523 Node* card_offset = __ URShiftX( cast, __ ConI(CardTableModRefBS::card_shift) );
3524
3525 // Combine card table base and card offset
3526 Node* card_adr = __ AddP(no_base, byte_map_base_node(), card_offset );
3527
3528 // If we know the value being stored does it cross regions?
3529
3530 if (val != NULL) {
3531 // Does the store cause us to cross regions?
3532
3533 // Should be able to do an unsigned compare of region_size instead of
3534 // and extra shift. Do we have an unsigned compare??
3535 // Node* region_size = __ ConI(1 << HeapRegion::LogOfHRGrainBytes);
3536 Node* xor_res = __ URShiftX ( __ XorX( cast, __ CastPX(__ ctrl(), val)), __ ConI(HeapRegion::LogOfHRGrainBytes));
3537
3538 // if (xor_res == 0) same region so skip
3539 __ if_then(xor_res, BoolTest::ne, zeroX); {
3540
3541 // No barrier if we are storing a NULL
3542 __ if_then(val, BoolTest::ne, null(), unlikely); {
3543
3544 // Ok must mark the card if not already dirty
3545
3546 // load the original value of the card
3547 Node* card_val = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw);
3548
3549 __ if_then(card_val, BoolTest::ne, zero); {
3550 g1_mark_card(ideal, card_adr, oop_store, alias_idx, index, index_adr, buffer, tf);
3551 } __ end_if();
3552 } __ end_if();
3553 } __ end_if();
3554 } else {
3555 // Object.clone() instrinsic uses this path.
3556 g1_mark_card(ideal, card_adr, oop_store, alias_idx, index, index_adr, buffer, tf);
3557 }
3558
3559 // Final sync IdealKit and GraphKit.
3560 sync_kit(ideal);
3561 }
3562 #undef __