1 /*
2 * Copyright (c) 2001, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "ci/ciUtilities.hpp"
27 #include "compiler/compileLog.hpp"
28 #include "gc/g1/g1BarrierSet.hpp"
29 #include "gc/g1/g1CardTable.hpp"
30 #include "gc/g1/heapRegion.hpp"
31 #include "gc/shared/barrierSet.hpp"
32 #include "gc/shared/cardTable.hpp"
33 #include "gc/shared/cardTableBarrierSet.hpp"
34 #include "gc/shared/collectedHeap.hpp"
35 #include "interpreter/interpreter.hpp"
36 #include "memory/resourceArea.hpp"
37 #include "opto/addnode.hpp"
38 #include "opto/castnode.hpp"
39 #include "opto/convertnode.hpp"
40 #include "opto/graphKit.hpp"
41 #include "opto/idealKit.hpp"
42 #include "opto/intrinsicnode.hpp"
43 #include "opto/locknode.hpp"
44 #include "opto/machnode.hpp"
45 #include "opto/opaquenode.hpp"
46 #include "opto/parse.hpp"
47 #include "opto/rootnode.hpp"
48 #include "opto/runtime.hpp"
49 #include "runtime/deoptimization.hpp"
50 #include "runtime/sharedRuntime.hpp"
51
52 //----------------------------GraphKit-----------------------------------------
53 // Main utility constructor.
54 GraphKit::GraphKit(JVMState* jvms)
55 : Phase(Phase::Parser),
56 _env(C->env()),
57 _gvn(*C->initial_gvn())
58 {
59 _exceptions = jvms->map()->next_exception();
60 if (_exceptions != NULL) jvms->map()->set_next_exception(NULL);
61 set_jvms(jvms);
62 }
63
64 // Private constructor for parser.
65 GraphKit::GraphKit()
66 : Phase(Phase::Parser),
67 _env(C->env()),
68 _gvn(*C->initial_gvn())
69 {
70 _exceptions = NULL;
71 set_map(NULL);
72 debug_only(_sp = -99);
73 debug_only(set_bci(-99));
74 }
75
76
77
78 //---------------------------clean_stack---------------------------------------
79 // Clear away rubbish from the stack area of the JVM state.
80 // This destroys any arguments that may be waiting on the stack.
81 void GraphKit::clean_stack(int from_sp) {
82 SafePointNode* map = this->map();
83 JVMState* jvms = this->jvms();
84 int stk_size = jvms->stk_size();
85 int stkoff = jvms->stkoff();
86 Node* top = this->top();
87 for (int i = from_sp; i < stk_size; i++) {
88 if (map->in(stkoff + i) != top) {
89 map->set_req(stkoff + i, top);
90 }
91 }
92 }
93
94
95 //--------------------------------sync_jvms-----------------------------------
96 // Make sure our current jvms agrees with our parse state.
97 JVMState* GraphKit::sync_jvms() const {
98 JVMState* jvms = this->jvms();
99 jvms->set_bci(bci()); // Record the new bci in the JVMState
100 jvms->set_sp(sp()); // Record the new sp in the JVMState
101 assert(jvms_in_sync(), "jvms is now in sync");
102 return jvms;
103 }
104
105 //--------------------------------sync_jvms_for_reexecute---------------------
106 // Make sure our current jvms agrees with our parse state. This version
107 // uses the reexecute_sp for reexecuting bytecodes.
108 JVMState* GraphKit::sync_jvms_for_reexecute() {
109 JVMState* jvms = this->jvms();
110 jvms->set_bci(bci()); // Record the new bci in the JVMState
111 jvms->set_sp(reexecute_sp()); // Record the new sp in the JVMState
112 return jvms;
113 }
114
115 #ifdef ASSERT
116 bool GraphKit::jvms_in_sync() const {
117 Parse* parse = is_Parse();
118 if (parse == NULL) {
119 if (bci() != jvms()->bci()) return false;
120 if (sp() != (int)jvms()->sp()) return false;
121 return true;
122 }
123 if (jvms()->method() != parse->method()) return false;
124 if (jvms()->bci() != parse->bci()) return false;
125 int jvms_sp = jvms()->sp();
126 if (jvms_sp != parse->sp()) return false;
127 int jvms_depth = jvms()->depth();
128 if (jvms_depth != parse->depth()) return false;
129 return true;
130 }
131
132 // Local helper checks for special internal merge points
133 // used to accumulate and merge exception states.
134 // They are marked by the region's in(0) edge being the map itself.
135 // Such merge points must never "escape" into the parser at large,
136 // until they have been handed to gvn.transform.
137 static bool is_hidden_merge(Node* reg) {
138 if (reg == NULL) return false;
139 if (reg->is_Phi()) {
140 reg = reg->in(0);
141 if (reg == NULL) return false;
142 }
143 return reg->is_Region() && reg->in(0) != NULL && reg->in(0)->is_Root();
144 }
145
146 void GraphKit::verify_map() const {
147 if (map() == NULL) return; // null map is OK
148 assert(map()->req() <= jvms()->endoff(), "no extra garbage on map");
149 assert(!map()->has_exceptions(), "call add_exception_states_from 1st");
150 assert(!is_hidden_merge(control()), "call use_exception_state, not set_map");
151 }
152
153 void GraphKit::verify_exception_state(SafePointNode* ex_map) {
154 assert(ex_map->next_exception() == NULL, "not already part of a chain");
155 assert(has_saved_ex_oop(ex_map), "every exception state has an ex_oop");
156 }
157 #endif
158
159 //---------------------------stop_and_kill_map---------------------------------
160 // Set _map to NULL, signalling a stop to further bytecode execution.
161 // First smash the current map's control to a constant, to mark it dead.
162 void GraphKit::stop_and_kill_map() {
163 SafePointNode* dead_map = stop();
164 if (dead_map != NULL) {
165 dead_map->disconnect_inputs(NULL, C); // Mark the map as killed.
166 assert(dead_map->is_killed(), "must be so marked");
167 }
168 }
169
170
171 //--------------------------------stopped--------------------------------------
172 // Tell if _map is NULL, or control is top.
173 bool GraphKit::stopped() {
174 if (map() == NULL) return true;
175 else if (control() == top()) return true;
176 else return false;
177 }
178
179
180 //-----------------------------has_ex_handler----------------------------------
181 // Tell if this method or any caller method has exception handlers.
182 bool GraphKit::has_ex_handler() {
183 for (JVMState* jvmsp = jvms(); jvmsp != NULL; jvmsp = jvmsp->caller()) {
184 if (jvmsp->has_method() && jvmsp->method()->has_exception_handlers()) {
185 return true;
186 }
187 }
188 return false;
189 }
190
191 //------------------------------save_ex_oop------------------------------------
192 // Save an exception without blowing stack contents or other JVM state.
193 void GraphKit::set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop) {
194 assert(!has_saved_ex_oop(ex_map), "clear ex-oop before setting again");
195 ex_map->add_req(ex_oop);
196 debug_only(verify_exception_state(ex_map));
197 }
198
199 inline static Node* common_saved_ex_oop(SafePointNode* ex_map, bool clear_it) {
200 assert(GraphKit::has_saved_ex_oop(ex_map), "ex_oop must be there");
201 Node* ex_oop = ex_map->in(ex_map->req()-1);
202 if (clear_it) ex_map->del_req(ex_map->req()-1);
203 return ex_oop;
204 }
205
206 //-----------------------------saved_ex_oop------------------------------------
207 // Recover a saved exception from its map.
208 Node* GraphKit::saved_ex_oop(SafePointNode* ex_map) {
209 return common_saved_ex_oop(ex_map, false);
210 }
211
212 //--------------------------clear_saved_ex_oop---------------------------------
213 // Erase a previously saved exception from its map.
214 Node* GraphKit::clear_saved_ex_oop(SafePointNode* ex_map) {
215 return common_saved_ex_oop(ex_map, true);
216 }
217
218 #ifdef ASSERT
219 //---------------------------has_saved_ex_oop----------------------------------
220 // Erase a previously saved exception from its map.
221 bool GraphKit::has_saved_ex_oop(SafePointNode* ex_map) {
222 return ex_map->req() == ex_map->jvms()->endoff()+1;
223 }
224 #endif
225
226 //-------------------------make_exception_state--------------------------------
227 // Turn the current JVM state into an exception state, appending the ex_oop.
228 SafePointNode* GraphKit::make_exception_state(Node* ex_oop) {
229 sync_jvms();
230 SafePointNode* ex_map = stop(); // do not manipulate this map any more
231 set_saved_ex_oop(ex_map, ex_oop);
232 return ex_map;
233 }
234
235
236 //--------------------------add_exception_state--------------------------------
237 // Add an exception to my list of exceptions.
238 void GraphKit::add_exception_state(SafePointNode* ex_map) {
239 if (ex_map == NULL || ex_map->control() == top()) {
240 return;
241 }
242 #ifdef ASSERT
243 verify_exception_state(ex_map);
244 if (has_exceptions()) {
245 assert(ex_map->jvms()->same_calls_as(_exceptions->jvms()), "all collected exceptions must come from the same place");
246 }
247 #endif
248
249 // If there is already an exception of exactly this type, merge with it.
250 // In particular, null-checks and other low-level exceptions common up here.
251 Node* ex_oop = saved_ex_oop(ex_map);
252 const Type* ex_type = _gvn.type(ex_oop);
253 if (ex_oop == top()) {
254 // No action needed.
255 return;
256 }
257 assert(ex_type->isa_instptr(), "exception must be an instance");
258 for (SafePointNode* e2 = _exceptions; e2 != NULL; e2 = e2->next_exception()) {
259 const Type* ex_type2 = _gvn.type(saved_ex_oop(e2));
260 // We check sp also because call bytecodes can generate exceptions
261 // both before and after arguments are popped!
262 if (ex_type2 == ex_type
263 && e2->_jvms->sp() == ex_map->_jvms->sp()) {
264 combine_exception_states(ex_map, e2);
265 return;
266 }
267 }
268
269 // No pre-existing exception of the same type. Chain it on the list.
270 push_exception_state(ex_map);
271 }
272
273 //-----------------------add_exception_states_from-----------------------------
274 void GraphKit::add_exception_states_from(JVMState* jvms) {
275 SafePointNode* ex_map = jvms->map()->next_exception();
276 if (ex_map != NULL) {
277 jvms->map()->set_next_exception(NULL);
278 for (SafePointNode* next_map; ex_map != NULL; ex_map = next_map) {
279 next_map = ex_map->next_exception();
280 ex_map->set_next_exception(NULL);
281 add_exception_state(ex_map);
282 }
283 }
284 }
285
286 //-----------------------transfer_exceptions_into_jvms-------------------------
287 JVMState* GraphKit::transfer_exceptions_into_jvms() {
288 if (map() == NULL) {
289 // We need a JVMS to carry the exceptions, but the map has gone away.
290 // Create a scratch JVMS, cloned from any of the exception states...
291 if (has_exceptions()) {
292 _map = _exceptions;
293 _map = clone_map();
294 _map->set_next_exception(NULL);
295 clear_saved_ex_oop(_map);
296 debug_only(verify_map());
297 } else {
298 // ...or created from scratch
299 JVMState* jvms = new (C) JVMState(_method, NULL);
300 jvms->set_bci(_bci);
301 jvms->set_sp(_sp);
302 jvms->set_map(new SafePointNode(TypeFunc::Parms, jvms));
303 set_jvms(jvms);
304 for (uint i = 0; i < map()->req(); i++) map()->init_req(i, top());
305 set_all_memory(top());
306 while (map()->req() < jvms->endoff()) map()->add_req(top());
307 }
308 // (This is a kludge, in case you didn't notice.)
309 set_control(top());
310 }
311 JVMState* jvms = sync_jvms();
312 assert(!jvms->map()->has_exceptions(), "no exceptions on this map yet");
313 jvms->map()->set_next_exception(_exceptions);
314 _exceptions = NULL; // done with this set of exceptions
315 return jvms;
316 }
317
318 static inline void add_n_reqs(Node* dstphi, Node* srcphi) {
319 assert(is_hidden_merge(dstphi), "must be a special merge node");
320 assert(is_hidden_merge(srcphi), "must be a special merge node");
321 uint limit = srcphi->req();
322 for (uint i = PhiNode::Input; i < limit; i++) {
323 dstphi->add_req(srcphi->in(i));
324 }
325 }
326 static inline void add_one_req(Node* dstphi, Node* src) {
327 assert(is_hidden_merge(dstphi), "must be a special merge node");
328 assert(!is_hidden_merge(src), "must not be a special merge node");
329 dstphi->add_req(src);
330 }
331
332 //-----------------------combine_exception_states------------------------------
333 // This helper function combines exception states by building phis on a
334 // specially marked state-merging region. These regions and phis are
335 // untransformed, and can build up gradually. The region is marked by
336 // having a control input of its exception map, rather than NULL. Such
337 // regions do not appear except in this function, and in use_exception_state.
338 void GraphKit::combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map) {
339 if (failing()) return; // dying anyway...
340 JVMState* ex_jvms = ex_map->_jvms;
341 assert(ex_jvms->same_calls_as(phi_map->_jvms), "consistent call chains");
342 assert(ex_jvms->stkoff() == phi_map->_jvms->stkoff(), "matching locals");
343 assert(ex_jvms->sp() == phi_map->_jvms->sp(), "matching stack sizes");
344 assert(ex_jvms->monoff() == phi_map->_jvms->monoff(), "matching JVMS");
345 assert(ex_jvms->scloff() == phi_map->_jvms->scloff(), "matching scalar replaced objects");
346 assert(ex_map->req() == phi_map->req(), "matching maps");
347 uint tos = ex_jvms->stkoff() + ex_jvms->sp();
348 Node* hidden_merge_mark = root();
349 Node* region = phi_map->control();
350 MergeMemNode* phi_mem = phi_map->merged_memory();
351 MergeMemNode* ex_mem = ex_map->merged_memory();
352 if (region->in(0) != hidden_merge_mark) {
353 // The control input is not (yet) a specially-marked region in phi_map.
354 // Make it so, and build some phis.
355 region = new RegionNode(2);
356 _gvn.set_type(region, Type::CONTROL);
357 region->set_req(0, hidden_merge_mark); // marks an internal ex-state
358 region->init_req(1, phi_map->control());
359 phi_map->set_control(region);
360 Node* io_phi = PhiNode::make(region, phi_map->i_o(), Type::ABIO);
361 record_for_igvn(io_phi);
362 _gvn.set_type(io_phi, Type::ABIO);
363 phi_map->set_i_o(io_phi);
364 for (MergeMemStream mms(phi_mem); mms.next_non_empty(); ) {
365 Node* m = mms.memory();
366 Node* m_phi = PhiNode::make(region, m, Type::MEMORY, mms.adr_type(C));
367 record_for_igvn(m_phi);
368 _gvn.set_type(m_phi, Type::MEMORY);
369 mms.set_memory(m_phi);
370 }
371 }
372
373 // Either or both of phi_map and ex_map might already be converted into phis.
374 Node* ex_control = ex_map->control();
375 // if there is special marking on ex_map also, we add multiple edges from src
376 bool add_multiple = (ex_control->in(0) == hidden_merge_mark);
377 // how wide was the destination phi_map, originally?
378 uint orig_width = region->req();
379
380 if (add_multiple) {
381 add_n_reqs(region, ex_control);
382 add_n_reqs(phi_map->i_o(), ex_map->i_o());
383 } else {
384 // ex_map has no merges, so we just add single edges everywhere
385 add_one_req(region, ex_control);
386 add_one_req(phi_map->i_o(), ex_map->i_o());
387 }
388 for (MergeMemStream mms(phi_mem, ex_mem); mms.next_non_empty2(); ) {
389 if (mms.is_empty()) {
390 // get a copy of the base memory, and patch some inputs into it
391 const TypePtr* adr_type = mms.adr_type(C);
392 Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
393 assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
394 mms.set_memory(phi);
395 // Prepare to append interesting stuff onto the newly sliced phi:
396 while (phi->req() > orig_width) phi->del_req(phi->req()-1);
397 }
398 // Append stuff from ex_map:
399 if (add_multiple) {
400 add_n_reqs(mms.memory(), mms.memory2());
401 } else {
402 add_one_req(mms.memory(), mms.memory2());
403 }
404 }
405 uint limit = ex_map->req();
406 for (uint i = TypeFunc::Parms; i < limit; i++) {
407 // Skip everything in the JVMS after tos. (The ex_oop follows.)
408 if (i == tos) i = ex_jvms->monoff();
409 Node* src = ex_map->in(i);
410 Node* dst = phi_map->in(i);
411 if (src != dst) {
412 PhiNode* phi;
413 if (dst->in(0) != region) {
414 dst = phi = PhiNode::make(region, dst, _gvn.type(dst));
415 record_for_igvn(phi);
416 _gvn.set_type(phi, phi->type());
417 phi_map->set_req(i, dst);
418 // Prepare to append interesting stuff onto the new phi:
419 while (dst->req() > orig_width) dst->del_req(dst->req()-1);
420 } else {
421 assert(dst->is_Phi(), "nobody else uses a hidden region");
422 phi = dst->as_Phi();
423 }
424 if (add_multiple && src->in(0) == ex_control) {
425 // Both are phis.
426 add_n_reqs(dst, src);
427 } else {
428 while (dst->req() < region->req()) add_one_req(dst, src);
429 }
430 const Type* srctype = _gvn.type(src);
431 if (phi->type() != srctype) {
432 const Type* dsttype = phi->type()->meet_speculative(srctype);
433 if (phi->type() != dsttype) {
434 phi->set_type(dsttype);
435 _gvn.set_type(phi, dsttype);
436 }
437 }
438 }
439 }
440 phi_map->merge_replaced_nodes_with(ex_map);
441 }
442
443 //--------------------------use_exception_state--------------------------------
444 Node* GraphKit::use_exception_state(SafePointNode* phi_map) {
445 if (failing()) { stop(); return top(); }
446 Node* region = phi_map->control();
447 Node* hidden_merge_mark = root();
448 assert(phi_map->jvms()->map() == phi_map, "sanity: 1-1 relation");
449 Node* ex_oop = clear_saved_ex_oop(phi_map);
450 if (region->in(0) == hidden_merge_mark) {
451 // Special marking for internal ex-states. Process the phis now.
452 region->set_req(0, region); // now it's an ordinary region
453 set_jvms(phi_map->jvms()); // ...so now we can use it as a map
454 // Note: Setting the jvms also sets the bci and sp.
455 set_control(_gvn.transform(region));
456 uint tos = jvms()->stkoff() + sp();
457 for (uint i = 1; i < tos; i++) {
458 Node* x = phi_map->in(i);
459 if (x->in(0) == region) {
460 assert(x->is_Phi(), "expected a special phi");
461 phi_map->set_req(i, _gvn.transform(x));
462 }
463 }
464 for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
465 Node* x = mms.memory();
466 if (x->in(0) == region) {
467 assert(x->is_Phi(), "nobody else uses a hidden region");
468 mms.set_memory(_gvn.transform(x));
469 }
470 }
471 if (ex_oop->in(0) == region) {
472 assert(ex_oop->is_Phi(), "expected a special phi");
473 ex_oop = _gvn.transform(ex_oop);
474 }
475 } else {
476 set_jvms(phi_map->jvms());
477 }
478
479 assert(!is_hidden_merge(phi_map->control()), "hidden ex. states cleared");
480 assert(!is_hidden_merge(phi_map->i_o()), "hidden ex. states cleared");
481 return ex_oop;
482 }
483
484 //---------------------------------java_bc-------------------------------------
485 Bytecodes::Code GraphKit::java_bc() const {
486 ciMethod* method = this->method();
487 int bci = this->bci();
488 if (method != NULL && bci != InvocationEntryBci)
489 return method->java_code_at_bci(bci);
490 else
491 return Bytecodes::_illegal;
492 }
493
494 void GraphKit::uncommon_trap_if_should_post_on_exceptions(Deoptimization::DeoptReason reason,
495 bool must_throw) {
496 // if the exception capability is set, then we will generate code
497 // to check the JavaThread.should_post_on_exceptions flag to see
498 // if we actually need to report exception events (for this
499 // thread). If we don't need to report exception events, we will
500 // take the normal fast path provided by add_exception_events. If
501 // exception event reporting is enabled for this thread, we will
502 // take the uncommon_trap in the BuildCutout below.
503
504 // first must access the should_post_on_exceptions_flag in this thread's JavaThread
505 Node* jthread = _gvn.transform(new ThreadLocalNode());
506 Node* adr = basic_plus_adr(top(), jthread, in_bytes(JavaThread::should_post_on_exceptions_flag_offset()));
507 Node* should_post_flag = make_load(control(), adr, TypeInt::INT, T_INT, Compile::AliasIdxRaw, MemNode::unordered);
508
509 // Test the should_post_on_exceptions_flag vs. 0
510 Node* chk = _gvn.transform( new CmpINode(should_post_flag, intcon(0)) );
511 Node* tst = _gvn.transform( new BoolNode(chk, BoolTest::eq) );
512
513 // Branch to slow_path if should_post_on_exceptions_flag was true
514 { BuildCutout unless(this, tst, PROB_MAX);
515 // Do not try anything fancy if we're notifying the VM on every throw.
516 // Cf. case Bytecodes::_athrow in parse2.cpp.
517 uncommon_trap(reason, Deoptimization::Action_none,
518 (ciKlass*)NULL, (char*)NULL, must_throw);
519 }
520
521 }
522
523 //------------------------------builtin_throw----------------------------------
524 void GraphKit::builtin_throw(Deoptimization::DeoptReason reason, Node* arg) {
525 bool must_throw = true;
526
527 if (env()->jvmti_can_post_on_exceptions()) {
528 // check if we must post exception events, take uncommon trap if so
529 uncommon_trap_if_should_post_on_exceptions(reason, must_throw);
530 // here if should_post_on_exceptions is false
531 // continue on with the normal codegen
532 }
533
534 // If this particular condition has not yet happened at this
535 // bytecode, then use the uncommon trap mechanism, and allow for
536 // a future recompilation if several traps occur here.
537 // If the throw is hot, try to use a more complicated inline mechanism
538 // which keeps execution inside the compiled code.
539 bool treat_throw_as_hot = false;
540 ciMethodData* md = method()->method_data();
541
542 if (ProfileTraps) {
543 if (too_many_traps(reason)) {
544 treat_throw_as_hot = true;
545 }
546 // (If there is no MDO at all, assume it is early in
547 // execution, and that any deopts are part of the
548 // startup transient, and don't need to be remembered.)
549
550 // Also, if there is a local exception handler, treat all throws
551 // as hot if there has been at least one in this method.
552 if (C->trap_count(reason) != 0
553 && method()->method_data()->trap_count(reason) != 0
554 && has_ex_handler()) {
555 treat_throw_as_hot = true;
556 }
557 }
558
559 // If this throw happens frequently, an uncommon trap might cause
560 // a performance pothole. If there is a local exception handler,
561 // and if this particular bytecode appears to be deoptimizing often,
562 // let us handle the throw inline, with a preconstructed instance.
563 // Note: If the deopt count has blown up, the uncommon trap
564 // runtime is going to flush this nmethod, not matter what.
565 if (treat_throw_as_hot
566 && (!StackTraceInThrowable || OmitStackTraceInFastThrow)) {
567 // If the throw is local, we use a pre-existing instance and
568 // punt on the backtrace. This would lead to a missing backtrace
569 // (a repeat of 4292742) if the backtrace object is ever asked
570 // for its backtrace.
571 // Fixing this remaining case of 4292742 requires some flavor of
572 // escape analysis. Leave that for the future.
573 ciInstance* ex_obj = NULL;
574 switch (reason) {
575 case Deoptimization::Reason_null_check:
576 ex_obj = env()->NullPointerException_instance();
577 break;
578 case Deoptimization::Reason_div0_check:
579 ex_obj = env()->ArithmeticException_instance();
580 break;
581 case Deoptimization::Reason_range_check:
582 ex_obj = env()->ArrayIndexOutOfBoundsException_instance();
583 break;
584 case Deoptimization::Reason_class_check:
585 if (java_bc() == Bytecodes::_aastore) {
586 ex_obj = env()->ArrayStoreException_instance();
587 } else {
588 ex_obj = env()->ClassCastException_instance();
589 }
590 break;
591 default:
592 break;
593 }
594 if (failing()) { stop(); return; } // exception allocation might fail
595 if (ex_obj != NULL) {
596 // Cheat with a preallocated exception object.
597 if (C->log() != NULL)
598 C->log()->elem("hot_throw preallocated='1' reason='%s'",
599 Deoptimization::trap_reason_name(reason));
600 const TypeInstPtr* ex_con = TypeInstPtr::make(ex_obj);
601 Node* ex_node = _gvn.transform(ConNode::make(ex_con));
602
603 // Clear the detail message of the preallocated exception object.
604 // Weblogic sometimes mutates the detail message of exceptions
605 // using reflection.
606 int offset = java_lang_Throwable::get_detailMessage_offset();
607 const TypePtr* adr_typ = ex_con->add_offset(offset);
608
609 Node *adr = basic_plus_adr(ex_node, ex_node, offset);
610 const TypeOopPtr* val_type = TypeOopPtr::make_from_klass(env()->String_klass());
611 // Conservatively release stores of object references.
612 Node *store = store_oop_to_object(control(), ex_node, adr, adr_typ, null(), val_type, T_OBJECT, MemNode::release);
613
614 add_exception_state(make_exception_state(ex_node));
615 return;
616 }
617 }
618
619 // %%% Maybe add entry to OptoRuntime which directly throws the exc.?
620 // It won't be much cheaper than bailing to the interp., since we'll
621 // have to pass up all the debug-info, and the runtime will have to
622 // create the stack trace.
623
624 // Usual case: Bail to interpreter.
625 // Reserve the right to recompile if we haven't seen anything yet.
626
627 ciMethod* m = Deoptimization::reason_is_speculate(reason) ? C->method() : NULL;
628 Deoptimization::DeoptAction action = Deoptimization::Action_maybe_recompile;
629 if (treat_throw_as_hot
630 && (method()->method_data()->trap_recompiled_at(bci(), m)
631 || C->too_many_traps(reason))) {
632 // We cannot afford to take more traps here. Suffer in the interpreter.
633 if (C->log() != NULL)
634 C->log()->elem("hot_throw preallocated='0' reason='%s' mcount='%d'",
635 Deoptimization::trap_reason_name(reason),
636 C->trap_count(reason));
637 action = Deoptimization::Action_none;
638 }
639
640 // "must_throw" prunes the JVM state to include only the stack, if there
641 // are no local exception handlers. This should cut down on register
642 // allocation time and code size, by drastically reducing the number
643 // of in-edges on the call to the uncommon trap.
644
645 uncommon_trap(reason, action, (ciKlass*)NULL, (char*)NULL, must_throw);
646 }
647
648
649 //----------------------------PreserveJVMState---------------------------------
650 PreserveJVMState::PreserveJVMState(GraphKit* kit, bool clone_map) {
651 debug_only(kit->verify_map());
652 _kit = kit;
653 _map = kit->map(); // preserve the map
654 _sp = kit->sp();
655 kit->set_map(clone_map ? kit->clone_map() : NULL);
656 #ifdef ASSERT
657 _bci = kit->bci();
658 Parse* parser = kit->is_Parse();
659 int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo();
660 _block = block;
661 #endif
662 }
663 PreserveJVMState::~PreserveJVMState() {
664 GraphKit* kit = _kit;
665 #ifdef ASSERT
666 assert(kit->bci() == _bci, "bci must not shift");
667 Parse* parser = kit->is_Parse();
668 int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo();
669 assert(block == _block, "block must not shift");
670 #endif
671 kit->set_map(_map);
672 kit->set_sp(_sp);
673 }
674
675
676 //-----------------------------BuildCutout-------------------------------------
677 BuildCutout::BuildCutout(GraphKit* kit, Node* p, float prob, float cnt)
678 : PreserveJVMState(kit)
679 {
680 assert(p->is_Con() || p->is_Bool(), "test must be a bool");
681 SafePointNode* outer_map = _map; // preserved map is caller's
682 SafePointNode* inner_map = kit->map();
683 IfNode* iff = kit->create_and_map_if(outer_map->control(), p, prob, cnt);
684 outer_map->set_control(kit->gvn().transform( new IfTrueNode(iff) ));
685 inner_map->set_control(kit->gvn().transform( new IfFalseNode(iff) ));
686 }
687 BuildCutout::~BuildCutout() {
688 GraphKit* kit = _kit;
689 assert(kit->stopped(), "cutout code must stop, throw, return, etc.");
690 }
691
692 //---------------------------PreserveReexecuteState----------------------------
693 PreserveReexecuteState::PreserveReexecuteState(GraphKit* kit) {
694 assert(!kit->stopped(), "must call stopped() before");
695 _kit = kit;
696 _sp = kit->sp();
697 _reexecute = kit->jvms()->_reexecute;
698 }
699 PreserveReexecuteState::~PreserveReexecuteState() {
700 if (_kit->stopped()) return;
701 _kit->jvms()->_reexecute = _reexecute;
702 _kit->set_sp(_sp);
703 }
704
705 //------------------------------clone_map--------------------------------------
706 // Implementation of PreserveJVMState
707 //
708 // Only clone_map(...) here. If this function is only used in the
709 // PreserveJVMState class we may want to get rid of this extra
710 // function eventually and do it all there.
711
712 SafePointNode* GraphKit::clone_map() {
713 if (map() == NULL) return NULL;
714
715 // Clone the memory edge first
716 Node* mem = MergeMemNode::make(map()->memory());
717 gvn().set_type_bottom(mem);
718
719 SafePointNode *clonemap = (SafePointNode*)map()->clone();
720 JVMState* jvms = this->jvms();
721 JVMState* clonejvms = jvms->clone_shallow(C);
722 clonemap->set_memory(mem);
723 clonemap->set_jvms(clonejvms);
724 clonejvms->set_map(clonemap);
725 record_for_igvn(clonemap);
726 gvn().set_type_bottom(clonemap);
727 return clonemap;
728 }
729
730
731 //-----------------------------set_map_clone-----------------------------------
732 void GraphKit::set_map_clone(SafePointNode* m) {
733 _map = m;
734 _map = clone_map();
735 _map->set_next_exception(NULL);
736 debug_only(verify_map());
737 }
738
739
740 //----------------------------kill_dead_locals---------------------------------
741 // Detect any locals which are known to be dead, and force them to top.
742 void GraphKit::kill_dead_locals() {
743 // Consult the liveness information for the locals. If any
744 // of them are unused, then they can be replaced by top(). This
745 // should help register allocation time and cut down on the size
746 // of the deoptimization information.
747
748 // This call is made from many of the bytecode handling
749 // subroutines called from the Big Switch in do_one_bytecode.
750 // Every bytecode which might include a slow path is responsible
751 // for killing its dead locals. The more consistent we
752 // are about killing deads, the fewer useless phis will be
753 // constructed for them at various merge points.
754
755 // bci can be -1 (InvocationEntryBci). We return the entry
756 // liveness for the method.
757
758 if (method() == NULL || method()->code_size() == 0) {
759 // We are building a graph for a call to a native method.
760 // All locals are live.
761 return;
762 }
763
764 ResourceMark rm;
765
766 // Consult the liveness information for the locals. If any
767 // of them are unused, then they can be replaced by top(). This
768 // should help register allocation time and cut down on the size
769 // of the deoptimization information.
770 MethodLivenessResult live_locals = method()->liveness_at_bci(bci());
771
772 int len = (int)live_locals.size();
773 assert(len <= jvms()->loc_size(), "too many live locals");
774 for (int local = 0; local < len; local++) {
775 if (!live_locals.at(local)) {
776 set_local(local, top());
777 }
778 }
779 }
780
781 #ifdef ASSERT
782 //-------------------------dead_locals_are_killed------------------------------
783 // Return true if all dead locals are set to top in the map.
784 // Used to assert "clean" debug info at various points.
785 bool GraphKit::dead_locals_are_killed() {
786 if (method() == NULL || method()->code_size() == 0) {
787 // No locals need to be dead, so all is as it should be.
788 return true;
789 }
790
791 // Make sure somebody called kill_dead_locals upstream.
792 ResourceMark rm;
793 for (JVMState* jvms = this->jvms(); jvms != NULL; jvms = jvms->caller()) {
794 if (jvms->loc_size() == 0) continue; // no locals to consult
795 SafePointNode* map = jvms->map();
796 ciMethod* method = jvms->method();
797 int bci = jvms->bci();
798 if (jvms == this->jvms()) {
799 bci = this->bci(); // it might not yet be synched
800 }
801 MethodLivenessResult live_locals = method->liveness_at_bci(bci);
802 int len = (int)live_locals.size();
803 if (!live_locals.is_valid() || len == 0)
804 // This method is trivial, or is poisoned by a breakpoint.
805 return true;
806 assert(len == jvms->loc_size(), "live map consistent with locals map");
807 for (int local = 0; local < len; local++) {
808 if (!live_locals.at(local) && map->local(jvms, local) != top()) {
809 if (PrintMiscellaneous && (Verbose || WizardMode)) {
810 tty->print_cr("Zombie local %d: ", local);
811 jvms->dump();
812 }
813 return false;
814 }
815 }
816 }
817 return true;
818 }
819
820 #endif //ASSERT
821
822 // Helper function for enforcing certain bytecodes to reexecute if
823 // deoptimization happens
824 static bool should_reexecute_implied_by_bytecode(JVMState *jvms, bool is_anewarray) {
825 ciMethod* cur_method = jvms->method();
826 int cur_bci = jvms->bci();
827 if (cur_method != NULL && cur_bci != InvocationEntryBci) {
828 Bytecodes::Code code = cur_method->java_code_at_bci(cur_bci);
829 return Interpreter::bytecode_should_reexecute(code) ||
830 (is_anewarray && code == Bytecodes::_multianewarray);
831 // Reexecute _multianewarray bytecode which was replaced with
832 // sequence of [a]newarray. See Parse::do_multianewarray().
833 //
834 // Note: interpreter should not have it set since this optimization
835 // is limited by dimensions and guarded by flag so in some cases
836 // multianewarray() runtime calls will be generated and
837 // the bytecode should not be reexecutes (stack will not be reset).
838 } else
839 return false;
840 }
841
842 // Helper function for adding JVMState and debug information to node
843 void GraphKit::add_safepoint_edges(SafePointNode* call, bool must_throw) {
844 // Add the safepoint edges to the call (or other safepoint).
845
846 // Make sure dead locals are set to top. This
847 // should help register allocation time and cut down on the size
848 // of the deoptimization information.
849 assert(dead_locals_are_killed(), "garbage in debug info before safepoint");
850
851 // Walk the inline list to fill in the correct set of JVMState's
852 // Also fill in the associated edges for each JVMState.
853
854 // If the bytecode needs to be reexecuted we need to put
855 // the arguments back on the stack.
856 const bool should_reexecute = jvms()->should_reexecute();
857 JVMState* youngest_jvms = should_reexecute ? sync_jvms_for_reexecute() : sync_jvms();
858
859 // NOTE: set_bci (called from sync_jvms) might reset the reexecute bit to
860 // undefined if the bci is different. This is normal for Parse but it
861 // should not happen for LibraryCallKit because only one bci is processed.
862 assert(!is_LibraryCallKit() || (jvms()->should_reexecute() == should_reexecute),
863 "in LibraryCallKit the reexecute bit should not change");
864
865 // If we are guaranteed to throw, we can prune everything but the
866 // input to the current bytecode.
867 bool can_prune_locals = false;
868 uint stack_slots_not_pruned = 0;
869 int inputs = 0, depth = 0;
870 if (must_throw) {
871 assert(method() == youngest_jvms->method(), "sanity");
872 if (compute_stack_effects(inputs, depth)) {
873 can_prune_locals = true;
874 stack_slots_not_pruned = inputs;
875 }
876 }
877
878 if (env()->should_retain_local_variables()) {
879 // At any safepoint, this method can get breakpointed, which would
880 // then require an immediate deoptimization.
881 can_prune_locals = false; // do not prune locals
882 stack_slots_not_pruned = 0;
883 }
884
885 // do not scribble on the input jvms
886 JVMState* out_jvms = youngest_jvms->clone_deep(C);
887 call->set_jvms(out_jvms); // Start jvms list for call node
888
889 // For a known set of bytecodes, the interpreter should reexecute them if
890 // deoptimization happens. We set the reexecute state for them here
891 if (out_jvms->is_reexecute_undefined() && //don't change if already specified
892 should_reexecute_implied_by_bytecode(out_jvms, call->is_AllocateArray())) {
893 out_jvms->set_should_reexecute(true); //NOTE: youngest_jvms not changed
894 }
895
896 // Presize the call:
897 DEBUG_ONLY(uint non_debug_edges = call->req());
898 call->add_req_batch(top(), youngest_jvms->debug_depth());
899 assert(call->req() == non_debug_edges + youngest_jvms->debug_depth(), "");
900
901 // Set up edges so that the call looks like this:
902 // Call [state:] ctl io mem fptr retadr
903 // [parms:] parm0 ... parmN
904 // [root:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
905 // [...mid:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN [...]
906 // [young:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
907 // Note that caller debug info precedes callee debug info.
908
909 // Fill pointer walks backwards from "young:" to "root:" in the diagram above:
910 uint debug_ptr = call->req();
911
912 // Loop over the map input edges associated with jvms, add them
913 // to the call node, & reset all offsets to match call node array.
914 for (JVMState* in_jvms = youngest_jvms; in_jvms != NULL; ) {
915 uint debug_end = debug_ptr;
916 uint debug_start = debug_ptr - in_jvms->debug_size();
917 debug_ptr = debug_start; // back up the ptr
918
919 uint p = debug_start; // walks forward in [debug_start, debug_end)
920 uint j, k, l;
921 SafePointNode* in_map = in_jvms->map();
922 out_jvms->set_map(call);
923
924 if (can_prune_locals) {
925 assert(in_jvms->method() == out_jvms->method(), "sanity");
926 // If the current throw can reach an exception handler in this JVMS,
927 // then we must keep everything live that can reach that handler.
928 // As a quick and dirty approximation, we look for any handlers at all.
929 if (in_jvms->method()->has_exception_handlers()) {
930 can_prune_locals = false;
931 }
932 }
933
934 // Add the Locals
935 k = in_jvms->locoff();
936 l = in_jvms->loc_size();
937 out_jvms->set_locoff(p);
938 if (!can_prune_locals) {
939 for (j = 0; j < l; j++)
940 call->set_req(p++, in_map->in(k+j));
941 } else {
942 p += l; // already set to top above by add_req_batch
943 }
944
945 // Add the Expression Stack
946 k = in_jvms->stkoff();
947 l = in_jvms->sp();
948 out_jvms->set_stkoff(p);
949 if (!can_prune_locals) {
950 for (j = 0; j < l; j++)
951 call->set_req(p++, in_map->in(k+j));
952 } else if (can_prune_locals && stack_slots_not_pruned != 0) {
953 // Divide stack into {S0,...,S1}, where S0 is set to top.
954 uint s1 = stack_slots_not_pruned;
955 stack_slots_not_pruned = 0; // for next iteration
956 if (s1 > l) s1 = l;
957 uint s0 = l - s1;
958 p += s0; // skip the tops preinstalled by add_req_batch
959 for (j = s0; j < l; j++)
960 call->set_req(p++, in_map->in(k+j));
961 } else {
962 p += l; // already set to top above by add_req_batch
963 }
964
965 // Add the Monitors
966 k = in_jvms->monoff();
967 l = in_jvms->mon_size();
968 out_jvms->set_monoff(p);
969 for (j = 0; j < l; j++)
970 call->set_req(p++, in_map->in(k+j));
971
972 // Copy any scalar object fields.
973 k = in_jvms->scloff();
974 l = in_jvms->scl_size();
975 out_jvms->set_scloff(p);
976 for (j = 0; j < l; j++)
977 call->set_req(p++, in_map->in(k+j));
978
979 // Finish the new jvms.
980 out_jvms->set_endoff(p);
981
982 assert(out_jvms->endoff() == debug_end, "fill ptr must match");
983 assert(out_jvms->depth() == in_jvms->depth(), "depth must match");
984 assert(out_jvms->loc_size() == in_jvms->loc_size(), "size must match");
985 assert(out_jvms->mon_size() == in_jvms->mon_size(), "size must match");
986 assert(out_jvms->scl_size() == in_jvms->scl_size(), "size must match");
987 assert(out_jvms->debug_size() == in_jvms->debug_size(), "size must match");
988
989 // Update the two tail pointers in parallel.
990 out_jvms = out_jvms->caller();
991 in_jvms = in_jvms->caller();
992 }
993
994 assert(debug_ptr == non_debug_edges, "debug info must fit exactly");
995
996 // Test the correctness of JVMState::debug_xxx accessors:
997 assert(call->jvms()->debug_start() == non_debug_edges, "");
998 assert(call->jvms()->debug_end() == call->req(), "");
999 assert(call->jvms()->debug_depth() == call->req() - non_debug_edges, "");
1000 }
1001
1002 bool GraphKit::compute_stack_effects(int& inputs, int& depth) {
1003 Bytecodes::Code code = java_bc();
1004 if (code == Bytecodes::_wide) {
1005 code = method()->java_code_at_bci(bci() + 1);
1006 }
1007
1008 BasicType rtype = T_ILLEGAL;
1009 int rsize = 0;
1010
1011 if (code != Bytecodes::_illegal) {
1012 depth = Bytecodes::depth(code); // checkcast=0, athrow=-1
1013 rtype = Bytecodes::result_type(code); // checkcast=P, athrow=V
1014 if (rtype < T_CONFLICT)
1015 rsize = type2size[rtype];
1016 }
1017
1018 switch (code) {
1019 case Bytecodes::_illegal:
1020 return false;
1021
1022 case Bytecodes::_ldc:
1023 case Bytecodes::_ldc_w:
1024 case Bytecodes::_ldc2_w:
1025 inputs = 0;
1026 break;
1027
1028 case Bytecodes::_dup: inputs = 1; break;
1029 case Bytecodes::_dup_x1: inputs = 2; break;
1030 case Bytecodes::_dup_x2: inputs = 3; break;
1031 case Bytecodes::_dup2: inputs = 2; break;
1032 case Bytecodes::_dup2_x1: inputs = 3; break;
1033 case Bytecodes::_dup2_x2: inputs = 4; break;
1034 case Bytecodes::_swap: inputs = 2; break;
1035 case Bytecodes::_arraylength: inputs = 1; break;
1036
1037 case Bytecodes::_getstatic:
1038 case Bytecodes::_putstatic:
1039 case Bytecodes::_getfield:
1040 case Bytecodes::_putfield:
1041 {
1042 bool ignored_will_link;
1043 ciField* field = method()->get_field_at_bci(bci(), ignored_will_link);
1044 int size = field->type()->size();
1045 bool is_get = (depth >= 0), is_static = (depth & 1);
1046 inputs = (is_static ? 0 : 1);
1047 if (is_get) {
1048 depth = size - inputs;
1049 } else {
1050 inputs += size; // putxxx pops the value from the stack
1051 depth = - inputs;
1052 }
1053 }
1054 break;
1055
1056 case Bytecodes::_invokevirtual:
1057 case Bytecodes::_invokespecial:
1058 case Bytecodes::_invokestatic:
1059 case Bytecodes::_invokedynamic:
1060 case Bytecodes::_invokeinterface:
1061 {
1062 bool ignored_will_link;
1063 ciSignature* declared_signature = NULL;
1064 ciMethod* ignored_callee = method()->get_method_at_bci(bci(), ignored_will_link, &declared_signature);
1065 assert(declared_signature != NULL, "cannot be null");
1066 inputs = declared_signature->arg_size_for_bc(code);
1067 int size = declared_signature->return_type()->size();
1068 depth = size - inputs;
1069 }
1070 break;
1071
1072 case Bytecodes::_multianewarray:
1073 {
1074 ciBytecodeStream iter(method());
1075 iter.reset_to_bci(bci());
1076 iter.next();
1077 inputs = iter.get_dimensions();
1078 assert(rsize == 1, "");
1079 depth = rsize - inputs;
1080 }
1081 break;
1082
1083 case Bytecodes::_ireturn:
1084 case Bytecodes::_lreturn:
1085 case Bytecodes::_freturn:
1086 case Bytecodes::_dreturn:
1087 case Bytecodes::_areturn:
1088 assert(rsize == -depth, "");
1089 inputs = rsize;
1090 break;
1091
1092 case Bytecodes::_jsr:
1093 case Bytecodes::_jsr_w:
1094 inputs = 0;
1095 depth = 1; // S.B. depth=1, not zero
1096 break;
1097
1098 default:
1099 // bytecode produces a typed result
1100 inputs = rsize - depth;
1101 assert(inputs >= 0, "");
1102 break;
1103 }
1104
1105 #ifdef ASSERT
1106 // spot check
1107 int outputs = depth + inputs;
1108 assert(outputs >= 0, "sanity");
1109 switch (code) {
1110 case Bytecodes::_checkcast: assert(inputs == 1 && outputs == 1, ""); break;
1111 case Bytecodes::_athrow: assert(inputs == 1 && outputs == 0, ""); break;
1112 case Bytecodes::_aload_0: assert(inputs == 0 && outputs == 1, ""); break;
1113 case Bytecodes::_return: assert(inputs == 0 && outputs == 0, ""); break;
1114 case Bytecodes::_drem: assert(inputs == 4 && outputs == 2, ""); break;
1115 default: break;
1116 }
1117 #endif //ASSERT
1118
1119 return true;
1120 }
1121
1122
1123
1124 //------------------------------basic_plus_adr---------------------------------
1125 Node* GraphKit::basic_plus_adr(Node* base, Node* ptr, Node* offset) {
1126 // short-circuit a common case
1127 if (offset == intcon(0)) return ptr;
1128 return _gvn.transform( new AddPNode(base, ptr, offset) );
1129 }
1130
1131 Node* GraphKit::ConvI2L(Node* offset) {
1132 // short-circuit a common case
1133 jint offset_con = find_int_con(offset, Type::OffsetBot);
1134 if (offset_con != Type::OffsetBot) {
1135 return longcon((jlong) offset_con);
1136 }
1137 return _gvn.transform( new ConvI2LNode(offset));
1138 }
1139
1140 Node* GraphKit::ConvI2UL(Node* offset) {
1141 juint offset_con = (juint) find_int_con(offset, Type::OffsetBot);
1142 if (offset_con != (juint) Type::OffsetBot) {
1143 return longcon((julong) offset_con);
1144 }
1145 Node* conv = _gvn.transform( new ConvI2LNode(offset));
1146 Node* mask = _gvn.transform(ConLNode::make((julong) max_juint));
1147 return _gvn.transform( new AndLNode(conv, mask) );
1148 }
1149
1150 Node* GraphKit::ConvL2I(Node* offset) {
1151 // short-circuit a common case
1152 jlong offset_con = find_long_con(offset, (jlong)Type::OffsetBot);
1153 if (offset_con != (jlong)Type::OffsetBot) {
1154 return intcon((int) offset_con);
1155 }
1156 return _gvn.transform( new ConvL2INode(offset));
1157 }
1158
1159 //-------------------------load_object_klass-----------------------------------
1160 Node* GraphKit::load_object_klass(Node* obj) {
1161 // Special-case a fresh allocation to avoid building nodes:
1162 Node* akls = AllocateNode::Ideal_klass(obj, &_gvn);
1163 if (akls != NULL) return akls;
1164 Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes());
1165 return _gvn.transform(LoadKlassNode::make(_gvn, NULL, immutable_memory(), k_adr, TypeInstPtr::KLASS));
1166 }
1167
1168 //-------------------------load_array_length-----------------------------------
1169 Node* GraphKit::load_array_length(Node* array) {
1170 // Special-case a fresh allocation to avoid building nodes:
1171 AllocateArrayNode* alloc = AllocateArrayNode::Ideal_array_allocation(array, &_gvn);
1172 Node *alen;
1173 if (alloc == NULL) {
1174 Node *r_adr = basic_plus_adr(array, arrayOopDesc::length_offset_in_bytes());
1175 alen = _gvn.transform( new LoadRangeNode(0, immutable_memory(), r_adr, TypeInt::POS));
1176 } else {
1177 alen = alloc->Ideal_length();
1178 Node* ccast = alloc->make_ideal_length(_gvn.type(array)->is_oopptr(), &_gvn);
1179 if (ccast != alen) {
1180 alen = _gvn.transform(ccast);
1181 }
1182 }
1183 return alen;
1184 }
1185
1186 //------------------------------do_null_check----------------------------------
1187 // Helper function to do a NULL pointer check. Returned value is
1188 // the incoming address with NULL casted away. You are allowed to use the
1189 // not-null value only if you are control dependent on the test.
1190 #ifndef PRODUCT
1191 extern int explicit_null_checks_inserted,
1192 explicit_null_checks_elided;
1193 #endif
1194 Node* GraphKit::null_check_common(Node* value, BasicType type,
1195 // optional arguments for variations:
1196 bool assert_null,
1197 Node* *null_control,
1198 bool speculative) {
1199 assert(!assert_null || null_control == NULL, "not both at once");
1200 if (stopped()) return top();
1201 NOT_PRODUCT(explicit_null_checks_inserted++);
1202
1203 // Construct NULL check
1204 Node *chk = NULL;
1205 switch(type) {
1206 case T_LONG : chk = new CmpLNode(value, _gvn.zerocon(T_LONG)); break;
1207 case T_INT : chk = new CmpINode(value, _gvn.intcon(0)); break;
1208 case T_ARRAY : // fall through
1209 type = T_OBJECT; // simplify further tests
1210 case T_OBJECT : {
1211 const Type *t = _gvn.type( value );
1212
1213 const TypeOopPtr* tp = t->isa_oopptr();
1214 if (tp != NULL && tp->klass() != NULL && !tp->klass()->is_loaded()
1215 // Only for do_null_check, not any of its siblings:
1216 && !assert_null && null_control == NULL) {
1217 // Usually, any field access or invocation on an unloaded oop type
1218 // will simply fail to link, since the statically linked class is
1219 // likely also to be unloaded. However, in -Xcomp mode, sometimes
1220 // the static class is loaded but the sharper oop type is not.
1221 // Rather than checking for this obscure case in lots of places,
1222 // we simply observe that a null check on an unloaded class
1223 // will always be followed by a nonsense operation, so we
1224 // can just issue the uncommon trap here.
1225 // Our access to the unloaded class will only be correct
1226 // after it has been loaded and initialized, which requires
1227 // a trip through the interpreter.
1228 #ifndef PRODUCT
1229 if (WizardMode) { tty->print("Null check of unloaded "); tp->klass()->print(); tty->cr(); }
1230 #endif
1231 uncommon_trap(Deoptimization::Reason_unloaded,
1232 Deoptimization::Action_reinterpret,
1233 tp->klass(), "!loaded");
1234 return top();
1235 }
1236
1237 if (assert_null) {
1238 // See if the type is contained in NULL_PTR.
1239 // If so, then the value is already null.
1240 if (t->higher_equal(TypePtr::NULL_PTR)) {
1241 NOT_PRODUCT(explicit_null_checks_elided++);
1242 return value; // Elided null assert quickly!
1243 }
1244 } else {
1245 // See if mixing in the NULL pointer changes type.
1246 // If so, then the NULL pointer was not allowed in the original
1247 // type. In other words, "value" was not-null.
1248 if (t->meet(TypePtr::NULL_PTR) != t->remove_speculative()) {
1249 // same as: if (!TypePtr::NULL_PTR->higher_equal(t)) ...
1250 NOT_PRODUCT(explicit_null_checks_elided++);
1251 return value; // Elided null check quickly!
1252 }
1253 }
1254 chk = new CmpPNode( value, null() );
1255 break;
1256 }
1257
1258 default:
1259 fatal("unexpected type: %s", type2name(type));
1260 }
1261 assert(chk != NULL, "sanity check");
1262 chk = _gvn.transform(chk);
1263
1264 BoolTest::mask btest = assert_null ? BoolTest::eq : BoolTest::ne;
1265 BoolNode *btst = new BoolNode( chk, btest);
1266 Node *tst = _gvn.transform( btst );
1267
1268 //-----------
1269 // if peephole optimizations occurred, a prior test existed.
1270 // If a prior test existed, maybe it dominates as we can avoid this test.
1271 if (tst != btst && type == T_OBJECT) {
1272 // At this point we want to scan up the CFG to see if we can
1273 // find an identical test (and so avoid this test altogether).
1274 Node *cfg = control();
1275 int depth = 0;
1276 while( depth < 16 ) { // Limit search depth for speed
1277 if( cfg->Opcode() == Op_IfTrue &&
1278 cfg->in(0)->in(1) == tst ) {
1279 // Found prior test. Use "cast_not_null" to construct an identical
1280 // CastPP (and hence hash to) as already exists for the prior test.
1281 // Return that casted value.
1282 if (assert_null) {
1283 replace_in_map(value, null());
1284 return null(); // do not issue the redundant test
1285 }
1286 Node *oldcontrol = control();
1287 set_control(cfg);
1288 Node *res = cast_not_null(value);
1289 set_control(oldcontrol);
1290 NOT_PRODUCT(explicit_null_checks_elided++);
1291 return res;
1292 }
1293 cfg = IfNode::up_one_dom(cfg, /*linear_only=*/ true);
1294 if (cfg == NULL) break; // Quit at region nodes
1295 depth++;
1296 }
1297 }
1298
1299 //-----------
1300 // Branch to failure if null
1301 float ok_prob = PROB_MAX; // a priori estimate: nulls never happen
1302 Deoptimization::DeoptReason reason;
1303 if (assert_null) {
1304 reason = Deoptimization::reason_null_assert(speculative);
1305 } else if (type == T_OBJECT) {
1306 reason = Deoptimization::reason_null_check(speculative);
1307 } else {
1308 reason = Deoptimization::Reason_div0_check;
1309 }
1310 // %%% Since Reason_unhandled is not recorded on a per-bytecode basis,
1311 // ciMethodData::has_trap_at will return a conservative -1 if any
1312 // must-be-null assertion has failed. This could cause performance
1313 // problems for a method after its first do_null_assert failure.
1314 // Consider using 'Reason_class_check' instead?
1315
1316 // To cause an implicit null check, we set the not-null probability
1317 // to the maximum (PROB_MAX). For an explicit check the probability
1318 // is set to a smaller value.
1319 if (null_control != NULL || too_many_traps(reason)) {
1320 // probability is less likely
1321 ok_prob = PROB_LIKELY_MAG(3);
1322 } else if (!assert_null &&
1323 (ImplicitNullCheckThreshold > 0) &&
1324 method() != NULL &&
1325 (method()->method_data()->trap_count(reason)
1326 >= (uint)ImplicitNullCheckThreshold)) {
1327 ok_prob = PROB_LIKELY_MAG(3);
1328 }
1329
1330 if (null_control != NULL) {
1331 IfNode* iff = create_and_map_if(control(), tst, ok_prob, COUNT_UNKNOWN);
1332 Node* null_true = _gvn.transform( new IfFalseNode(iff));
1333 set_control( _gvn.transform( new IfTrueNode(iff)));
1334 #ifndef PRODUCT
1335 if (null_true == top()) {
1336 explicit_null_checks_elided++;
1337 }
1338 #endif
1339 (*null_control) = null_true;
1340 } else {
1341 BuildCutout unless(this, tst, ok_prob);
1342 // Check for optimizer eliding test at parse time
1343 if (stopped()) {
1344 // Failure not possible; do not bother making uncommon trap.
1345 NOT_PRODUCT(explicit_null_checks_elided++);
1346 } else if (assert_null) {
1347 uncommon_trap(reason,
1348 Deoptimization::Action_make_not_entrant,
1349 NULL, "assert_null");
1350 } else {
1351 replace_in_map(value, zerocon(type));
1352 builtin_throw(reason);
1353 }
1354 }
1355
1356 // Must throw exception, fall-thru not possible?
1357 if (stopped()) {
1358 return top(); // No result
1359 }
1360
1361 if (assert_null) {
1362 // Cast obj to null on this path.
1363 replace_in_map(value, zerocon(type));
1364 return zerocon(type);
1365 }
1366
1367 // Cast obj to not-null on this path, if there is no null_control.
1368 // (If there is a null_control, a non-null value may come back to haunt us.)
1369 if (type == T_OBJECT) {
1370 Node* cast = cast_not_null(value, false);
1371 if (null_control == NULL || (*null_control) == top())
1372 replace_in_map(value, cast);
1373 value = cast;
1374 }
1375
1376 return value;
1377 }
1378
1379
1380 //------------------------------cast_not_null----------------------------------
1381 // Cast obj to not-null on this path
1382 Node* GraphKit::cast_not_null(Node* obj, bool do_replace_in_map) {
1383 const Type *t = _gvn.type(obj);
1384 const Type *t_not_null = t->join_speculative(TypePtr::NOTNULL);
1385 // Object is already not-null?
1386 if( t == t_not_null ) return obj;
1387
1388 Node *cast = new CastPPNode(obj,t_not_null);
1389 cast->init_req(0, control());
1390 cast = _gvn.transform( cast );
1391
1392 // Scan for instances of 'obj' in the current JVM mapping.
1393 // These instances are known to be not-null after the test.
1394 if (do_replace_in_map)
1395 replace_in_map(obj, cast);
1396
1397 return cast; // Return casted value
1398 }
1399
1400 // Sometimes in intrinsics, we implicitly know an object is not null
1401 // (there's no actual null check) so we can cast it to not null. In
1402 // the course of optimizations, the input to the cast can become null.
1403 // In that case that data path will die and we need the control path
1404 // to become dead as well to keep the graph consistent. So we have to
1405 // add a check for null for which one branch can't be taken. It uses
1406 // an Opaque4 node that will cause the check to be removed after loop
1407 // opts so the test goes away and the compiled code doesn't execute a
1408 // useless check.
1409 Node* GraphKit::must_be_not_null(Node* value, bool do_replace_in_map) {
1410 Node* chk = _gvn.transform(new CmpPNode(value, null()));
1411 Node *tst = _gvn.transform(new BoolNode(chk, BoolTest::ne));
1412 Node* opaq = _gvn.transform(new Opaque4Node(C, tst, intcon(1)));
1413 IfNode *iff = new IfNode(control(), opaq, PROB_MAX, COUNT_UNKNOWN);
1414 _gvn.set_type(iff, iff->Value(&_gvn));
1415 Node *if_f = _gvn.transform(new IfFalseNode(iff));
1416 Node *frame = _gvn.transform(new ParmNode(C->start(), TypeFunc::FramePtr));
1417 Node *halt = _gvn.transform(new HaltNode(if_f, frame));
1418 C->root()->add_req(halt);
1419 Node *if_t = _gvn.transform(new IfTrueNode(iff));
1420 set_control(if_t);
1421 return cast_not_null(value, do_replace_in_map);
1422 }
1423
1424
1425 //--------------------------replace_in_map-------------------------------------
1426 void GraphKit::replace_in_map(Node* old, Node* neww) {
1427 if (old == neww) {
1428 return;
1429 }
1430
1431 map()->replace_edge(old, neww);
1432
1433 // Note: This operation potentially replaces any edge
1434 // on the map. This includes locals, stack, and monitors
1435 // of the current (innermost) JVM state.
1436
1437 // don't let inconsistent types from profiling escape this
1438 // method
1439
1440 const Type* told = _gvn.type(old);
1441 const Type* tnew = _gvn.type(neww);
1442
1443 if (!tnew->higher_equal(told)) {
1444 return;
1445 }
1446
1447 map()->record_replaced_node(old, neww);
1448 }
1449
1450
1451 //=============================================================================
1452 //--------------------------------memory---------------------------------------
1453 Node* GraphKit::memory(uint alias_idx) {
1454 MergeMemNode* mem = merged_memory();
1455 Node* p = mem->memory_at(alias_idx);
1456 _gvn.set_type(p, Type::MEMORY); // must be mapped
1457 return p;
1458 }
1459
1460 //-----------------------------reset_memory------------------------------------
1461 Node* GraphKit::reset_memory() {
1462 Node* mem = map()->memory();
1463 // do not use this node for any more parsing!
1464 debug_only( map()->set_memory((Node*)NULL) );
1465 return _gvn.transform( mem );
1466 }
1467
1468 //------------------------------set_all_memory---------------------------------
1469 void GraphKit::set_all_memory(Node* newmem) {
1470 Node* mergemem = MergeMemNode::make(newmem);
1471 gvn().set_type_bottom(mergemem);
1472 map()->set_memory(mergemem);
1473 }
1474
1475 //------------------------------set_all_memory_call----------------------------
1476 void GraphKit::set_all_memory_call(Node* call, bool separate_io_proj) {
1477 Node* newmem = _gvn.transform( new ProjNode(call, TypeFunc::Memory, separate_io_proj) );
1478 set_all_memory(newmem);
1479 }
1480
1481 //=============================================================================
1482 //
1483 // parser factory methods for MemNodes
1484 //
1485 // These are layered on top of the factory methods in LoadNode and StoreNode,
1486 // and integrate with the parser's memory state and _gvn engine.
1487 //
1488
1489 // factory methods in "int adr_idx"
1490 Node* GraphKit::make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
1491 int adr_idx,
1492 MemNode::MemOrd mo,
1493 LoadNode::ControlDependency control_dependency,
1494 bool require_atomic_access,
1495 bool unaligned,
1496 bool mismatched) {
1497 assert(adr_idx != Compile::AliasIdxTop, "use other make_load factory" );
1498 const TypePtr* adr_type = NULL; // debug-mode-only argument
1499 debug_only(adr_type = C->get_adr_type(adr_idx));
1500 Node* mem = memory(adr_idx);
1501 Node* ld;
1502 if (require_atomic_access && bt == T_LONG) {
1503 ld = LoadLNode::make_atomic(ctl, mem, adr, adr_type, t, mo, control_dependency, unaligned, mismatched);
1504 } else if (require_atomic_access && bt == T_DOUBLE) {
1505 ld = LoadDNode::make_atomic(ctl, mem, adr, adr_type, t, mo, control_dependency, unaligned, mismatched);
1506 } else {
1507 ld = LoadNode::make(_gvn, ctl, mem, adr, adr_type, t, bt, mo, control_dependency, unaligned, mismatched);
1508 }
1509 ld = _gvn.transform(ld);
1510 if (((bt == T_OBJECT) && C->do_escape_analysis()) || C->eliminate_boxing()) {
1511 // Improve graph before escape analysis and boxing elimination.
1512 record_for_igvn(ld);
1513 }
1514 return ld;
1515 }
1516
1517 Node* GraphKit::store_to_memory(Node* ctl, Node* adr, Node *val, BasicType bt,
1518 int adr_idx,
1519 MemNode::MemOrd mo,
1520 bool require_atomic_access,
1521 bool unaligned,
1522 bool mismatched) {
1523 assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1524 const TypePtr* adr_type = NULL;
1525 debug_only(adr_type = C->get_adr_type(adr_idx));
1526 Node *mem = memory(adr_idx);
1527 Node* st;
1528 if (require_atomic_access && bt == T_LONG) {
1529 st = StoreLNode::make_atomic(ctl, mem, adr, adr_type, val, mo);
1530 } else if (require_atomic_access && bt == T_DOUBLE) {
1531 st = StoreDNode::make_atomic(ctl, mem, adr, adr_type, val, mo);
1532 } else {
1533 st = StoreNode::make(_gvn, ctl, mem, adr, adr_type, val, bt, mo);
1534 }
1535 if (unaligned) {
1536 st->as_Store()->set_unaligned_access();
1537 }
1538 if (mismatched) {
1539 st->as_Store()->set_mismatched_access();
1540 }
1541 st = _gvn.transform(st);
1542 set_memory(st, adr_idx);
1543 // Back-to-back stores can only remove intermediate store with DU info
1544 // so push on worklist for optimizer.
1545 if (mem->req() > MemNode::Address && adr == mem->in(MemNode::Address))
1546 record_for_igvn(st);
1547
1548 return st;
1549 }
1550
1551
1552 void GraphKit::pre_barrier(bool do_load,
1553 Node* ctl,
1554 Node* obj,
1555 Node* adr,
1556 uint adr_idx,
1557 Node* val,
1558 const TypeOopPtr* val_type,
1559 Node* pre_val,
1560 BasicType bt) {
1561
1562 BarrierSet* bs = Universe::heap()->barrier_set();
1563 set_control(ctl);
1564 switch (bs->kind()) {
1565 case BarrierSet::G1BarrierSet:
1566 g1_write_barrier_pre(do_load, obj, adr, adr_idx, val, val_type, pre_val, bt);
1567 break;
1568
1569 case BarrierSet::CardTableBarrierSet:
1570 break;
1571
1572 default :
1573 ShouldNotReachHere();
1574
1575 }
1576 }
1577
1578 bool GraphKit::can_move_pre_barrier() const {
1579 BarrierSet* bs = Universe::heap()->barrier_set();
1580 switch (bs->kind()) {
1581 case BarrierSet::G1BarrierSet:
1582 return true; // Can move it if no safepoint
1583
1584 case BarrierSet::CardTableBarrierSet:
1585 return true; // There is no pre-barrier
1586
1587 default :
1588 ShouldNotReachHere();
1589 }
1590 return false;
1591 }
1592
1593 void GraphKit::post_barrier(Node* ctl,
1594 Node* store,
1595 Node* obj,
1596 Node* adr,
1597 uint adr_idx,
1598 Node* val,
1599 BasicType bt,
1600 bool use_precise) {
1601 BarrierSet* bs = Universe::heap()->barrier_set();
1602 set_control(ctl);
1603 switch (bs->kind()) {
1604 case BarrierSet::G1BarrierSet:
1605 g1_write_barrier_post(store, obj, adr, adr_idx, val, bt, use_precise);
1606 break;
1607
1608 case BarrierSet::CardTableBarrierSet:
1609 write_barrier_post(store, obj, adr, adr_idx, val, use_precise);
1610 break;
1611
1612 default :
1613 ShouldNotReachHere();
1614
1615 }
1616 }
1617
1618 Node* GraphKit::store_oop(Node* ctl,
1619 Node* obj,
1620 Node* adr,
1621 const TypePtr* adr_type,
1622 Node* val,
1623 const TypeOopPtr* val_type,
1624 BasicType bt,
1625 bool use_precise,
1626 MemNode::MemOrd mo,
1627 bool mismatched) {
1628 // Transformation of a value which could be NULL pointer (CastPP #NULL)
1629 // could be delayed during Parse (for example, in adjust_map_after_if()).
1630 // Execute transformation here to avoid barrier generation in such case.
1631 if (_gvn.type(val) == TypePtr::NULL_PTR)
1632 val = _gvn.makecon(TypePtr::NULL_PTR);
1633
1634 set_control(ctl);
1635 if (stopped()) return top(); // Dead path ?
1636
1637 assert(bt == T_OBJECT, "sanity");
1638 assert(val != NULL, "not dead path");
1639 uint adr_idx = C->get_alias_index(adr_type);
1640 assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1641
1642 pre_barrier(true /* do_load */,
1643 control(), obj, adr, adr_idx, val, val_type,
1644 NULL /* pre_val */,
1645 bt);
1646
1647 Node* store = store_to_memory(control(), adr, val, bt, adr_idx, mo, mismatched);
1648 post_barrier(control(), store, obj, adr, adr_idx, val, bt, use_precise);
1649 return store;
1650 }
1651
1652 // Could be an array or object we don't know at compile time (unsafe ref.)
1653 Node* GraphKit::store_oop_to_unknown(Node* ctl,
1654 Node* obj, // containing obj
1655 Node* adr, // actual adress to store val at
1656 const TypePtr* adr_type,
1657 Node* val,
1658 BasicType bt,
1659 MemNode::MemOrd mo,
1660 bool mismatched) {
1661 Compile::AliasType* at = C->alias_type(adr_type);
1662 const TypeOopPtr* val_type = NULL;
1663 if (adr_type->isa_instptr()) {
1664 if (at->field() != NULL) {
1665 // known field. This code is a copy of the do_put_xxx logic.
1666 ciField* field = at->field();
1667 if (!field->type()->is_loaded()) {
1668 val_type = TypeInstPtr::BOTTOM;
1669 } else {
1670 val_type = TypeOopPtr::make_from_klass(field->type()->as_klass());
1671 }
1672 }
1673 } else if (adr_type->isa_aryptr()) {
1674 val_type = adr_type->is_aryptr()->elem()->make_oopptr();
1675 }
1676 if (val_type == NULL) {
1677 val_type = TypeInstPtr::BOTTOM;
1678 }
1679 return store_oop(ctl, obj, adr, adr_type, val, val_type, bt, true, mo, mismatched);
1680 }
1681
1682
1683 //-------------------------array_element_address-------------------------
1684 Node* GraphKit::array_element_address(Node* ary, Node* idx, BasicType elembt,
1685 const TypeInt* sizetype, Node* ctrl) {
1686 uint shift = exact_log2(type2aelembytes(elembt));
1687 uint header = arrayOopDesc::base_offset_in_bytes(elembt);
1688
1689 // short-circuit a common case (saves lots of confusing waste motion)
1690 jint idx_con = find_int_con(idx, -1);
1691 if (idx_con >= 0) {
1692 intptr_t offset = header + ((intptr_t)idx_con << shift);
1693 return basic_plus_adr(ary, offset);
1694 }
1695
1696 // must be correct type for alignment purposes
1697 Node* base = basic_plus_adr(ary, header);
1698 idx = Compile::conv_I2X_index(&_gvn, idx, sizetype, ctrl);
1699 Node* scale = _gvn.transform( new LShiftXNode(idx, intcon(shift)) );
1700 return basic_plus_adr(ary, base, scale);
1701 }
1702
1703 //-------------------------load_array_element-------------------------
1704 Node* GraphKit::load_array_element(Node* ctl, Node* ary, Node* idx, const TypeAryPtr* arytype) {
1705 const Type* elemtype = arytype->elem();
1706 BasicType elembt = elemtype->array_element_basic_type();
1707 Node* adr = array_element_address(ary, idx, elembt, arytype->size());
1708 if (elembt == T_NARROWOOP) {
1709 elembt = T_OBJECT; // To satisfy switch in LoadNode::make()
1710 }
1711 Node* ld = make_load(ctl, adr, elemtype, elembt, arytype, MemNode::unordered);
1712 return ld;
1713 }
1714
1715 //-------------------------set_arguments_for_java_call-------------------------
1716 // Arguments (pre-popped from the stack) are taken from the JVMS.
1717 void GraphKit::set_arguments_for_java_call(CallJavaNode* call) {
1718 // Add the call arguments:
1719 uint nargs = call->method()->arg_size();
1720 for (uint i = 0; i < nargs; i++) {
1721 Node* arg = argument(i);
1722 call->init_req(i + TypeFunc::Parms, arg);
1723 }
1724 }
1725
1726 //---------------------------set_edges_for_java_call---------------------------
1727 // Connect a newly created call into the current JVMS.
1728 // A return value node (if any) is returned from set_edges_for_java_call.
1729 void GraphKit::set_edges_for_java_call(CallJavaNode* call, bool must_throw, bool separate_io_proj) {
1730
1731 // Add the predefined inputs:
1732 call->init_req( TypeFunc::Control, control() );
1733 call->init_req( TypeFunc::I_O , i_o() );
1734 call->init_req( TypeFunc::Memory , reset_memory() );
1735 call->init_req( TypeFunc::FramePtr, frameptr() );
1736 call->init_req( TypeFunc::ReturnAdr, top() );
1737
1738 add_safepoint_edges(call, must_throw);
1739
1740 Node* xcall = _gvn.transform(call);
1741
1742 if (xcall == top()) {
1743 set_control(top());
1744 return;
1745 }
1746 assert(xcall == call, "call identity is stable");
1747
1748 // Re-use the current map to produce the result.
1749
1750 set_control(_gvn.transform(new ProjNode(call, TypeFunc::Control)));
1751 set_i_o( _gvn.transform(new ProjNode(call, TypeFunc::I_O , separate_io_proj)));
1752 set_all_memory_call(xcall, separate_io_proj);
1753
1754 //return xcall; // no need, caller already has it
1755 }
1756
1757 Node* GraphKit::set_results_for_java_call(CallJavaNode* call, bool separate_io_proj) {
1758 if (stopped()) return top(); // maybe the call folded up?
1759
1760 // Capture the return value, if any.
1761 Node* ret;
1762 if (call->method() == NULL ||
1763 call->method()->return_type()->basic_type() == T_VOID)
1764 ret = top();
1765 else ret = _gvn.transform(new ProjNode(call, TypeFunc::Parms));
1766
1767 // Note: Since any out-of-line call can produce an exception,
1768 // we always insert an I_O projection from the call into the result.
1769
1770 make_slow_call_ex(call, env()->Throwable_klass(), separate_io_proj);
1771
1772 if (separate_io_proj) {
1773 // The caller requested separate projections be used by the fall
1774 // through and exceptional paths, so replace the projections for
1775 // the fall through path.
1776 set_i_o(_gvn.transform( new ProjNode(call, TypeFunc::I_O) ));
1777 set_all_memory(_gvn.transform( new ProjNode(call, TypeFunc::Memory) ));
1778 }
1779 return ret;
1780 }
1781
1782 //--------------------set_predefined_input_for_runtime_call--------------------
1783 // Reading and setting the memory state is way conservative here.
1784 // The real problem is that I am not doing real Type analysis on memory,
1785 // so I cannot distinguish card mark stores from other stores. Across a GC
1786 // point the Store Barrier and the card mark memory has to agree. I cannot
1787 // have a card mark store and its barrier split across the GC point from
1788 // either above or below. Here I get that to happen by reading ALL of memory.
1789 // A better answer would be to separate out card marks from other memory.
1790 // For now, return the input memory state, so that it can be reused
1791 // after the call, if this call has restricted memory effects.
1792 Node* GraphKit::set_predefined_input_for_runtime_call(SafePointNode* call) {
1793 // Set fixed predefined input arguments
1794 Node* memory = reset_memory();
1795 call->init_req( TypeFunc::Control, control() );
1796 call->init_req( TypeFunc::I_O, top() ); // does no i/o
1797 call->init_req( TypeFunc::Memory, memory ); // may gc ptrs
1798 call->init_req( TypeFunc::FramePtr, frameptr() );
1799 call->init_req( TypeFunc::ReturnAdr, top() );
1800 return memory;
1801 }
1802
1803 //-------------------set_predefined_output_for_runtime_call--------------------
1804 // Set control and memory (not i_o) from the call.
1805 // If keep_mem is not NULL, use it for the output state,
1806 // except for the RawPtr output of the call, if hook_mem is TypeRawPtr::BOTTOM.
1807 // If hook_mem is NULL, this call produces no memory effects at all.
1808 // If hook_mem is a Java-visible memory slice (such as arraycopy operands),
1809 // then only that memory slice is taken from the call.
1810 // In the last case, we must put an appropriate memory barrier before
1811 // the call, so as to create the correct anti-dependencies on loads
1812 // preceding the call.
1813 void GraphKit::set_predefined_output_for_runtime_call(Node* call,
1814 Node* keep_mem,
1815 const TypePtr* hook_mem) {
1816 // no i/o
1817 set_control(_gvn.transform( new ProjNode(call,TypeFunc::Control) ));
1818 if (keep_mem) {
1819 // First clone the existing memory state
1820 set_all_memory(keep_mem);
1821 if (hook_mem != NULL) {
1822 // Make memory for the call
1823 Node* mem = _gvn.transform( new ProjNode(call, TypeFunc::Memory) );
1824 // Set the RawPtr memory state only. This covers all the heap top/GC stuff
1825 // We also use hook_mem to extract specific effects from arraycopy stubs.
1826 set_memory(mem, hook_mem);
1827 }
1828 // ...else the call has NO memory effects.
1829
1830 // Make sure the call advertises its memory effects precisely.
1831 // This lets us build accurate anti-dependences in gcm.cpp.
1832 assert(C->alias_type(call->adr_type()) == C->alias_type(hook_mem),
1833 "call node must be constructed correctly");
1834 } else {
1835 assert(hook_mem == NULL, "");
1836 // This is not a "slow path" call; all memory comes from the call.
1837 set_all_memory_call(call);
1838 }
1839 }
1840
1841
1842 // Replace the call with the current state of the kit.
1843 void GraphKit::replace_call(CallNode* call, Node* result, bool do_replaced_nodes) {
1844 JVMState* ejvms = NULL;
1845 if (has_exceptions()) {
1846 ejvms = transfer_exceptions_into_jvms();
1847 }
1848
1849 ReplacedNodes replaced_nodes = map()->replaced_nodes();
1850 ReplacedNodes replaced_nodes_exception;
1851 Node* ex_ctl = top();
1852
1853 SafePointNode* final_state = stop();
1854
1855 // Find all the needed outputs of this call
1856 CallProjections callprojs;
1857 call->extract_projections(&callprojs, true);
1858
1859 Node* init_mem = call->in(TypeFunc::Memory);
1860 Node* final_mem = final_state->in(TypeFunc::Memory);
1861 Node* final_ctl = final_state->in(TypeFunc::Control);
1862 Node* final_io = final_state->in(TypeFunc::I_O);
1863
1864 // Replace all the old call edges with the edges from the inlining result
1865 if (callprojs.fallthrough_catchproj != NULL) {
1866 C->gvn_replace_by(callprojs.fallthrough_catchproj, final_ctl);
1867 }
1868 if (callprojs.fallthrough_memproj != NULL) {
1869 if (final_mem->is_MergeMem()) {
1870 // Parser's exits MergeMem was not transformed but may be optimized
1871 final_mem = _gvn.transform(final_mem);
1872 }
1873 C->gvn_replace_by(callprojs.fallthrough_memproj, final_mem);
1874 }
1875 if (callprojs.fallthrough_ioproj != NULL) {
1876 C->gvn_replace_by(callprojs.fallthrough_ioproj, final_io);
1877 }
1878
1879 // Replace the result with the new result if it exists and is used
1880 if (callprojs.resproj != NULL && result != NULL) {
1881 C->gvn_replace_by(callprojs.resproj, result);
1882 }
1883
1884 if (ejvms == NULL) {
1885 // No exception edges to simply kill off those paths
1886 if (callprojs.catchall_catchproj != NULL) {
1887 C->gvn_replace_by(callprojs.catchall_catchproj, C->top());
1888 }
1889 if (callprojs.catchall_memproj != NULL) {
1890 C->gvn_replace_by(callprojs.catchall_memproj, C->top());
1891 }
1892 if (callprojs.catchall_ioproj != NULL) {
1893 C->gvn_replace_by(callprojs.catchall_ioproj, C->top());
1894 }
1895 // Replace the old exception object with top
1896 if (callprojs.exobj != NULL) {
1897 C->gvn_replace_by(callprojs.exobj, C->top());
1898 }
1899 } else {
1900 GraphKit ekit(ejvms);
1901
1902 // Load my combined exception state into the kit, with all phis transformed:
1903 SafePointNode* ex_map = ekit.combine_and_pop_all_exception_states();
1904 replaced_nodes_exception = ex_map->replaced_nodes();
1905
1906 Node* ex_oop = ekit.use_exception_state(ex_map);
1907
1908 if (callprojs.catchall_catchproj != NULL) {
1909 C->gvn_replace_by(callprojs.catchall_catchproj, ekit.control());
1910 ex_ctl = ekit.control();
1911 }
1912 if (callprojs.catchall_memproj != NULL) {
1913 C->gvn_replace_by(callprojs.catchall_memproj, ekit.reset_memory());
1914 }
1915 if (callprojs.catchall_ioproj != NULL) {
1916 C->gvn_replace_by(callprojs.catchall_ioproj, ekit.i_o());
1917 }
1918
1919 // Replace the old exception object with the newly created one
1920 if (callprojs.exobj != NULL) {
1921 C->gvn_replace_by(callprojs.exobj, ex_oop);
1922 }
1923 }
1924
1925 // Disconnect the call from the graph
1926 call->disconnect_inputs(NULL, C);
1927 C->gvn_replace_by(call, C->top());
1928
1929 // Clean up any MergeMems that feed other MergeMems since the
1930 // optimizer doesn't like that.
1931 if (final_mem->is_MergeMem()) {
1932 Node_List wl;
1933 for (SimpleDUIterator i(final_mem); i.has_next(); i.next()) {
1934 Node* m = i.get();
1935 if (m->is_MergeMem() && !wl.contains(m)) {
1936 wl.push(m);
1937 }
1938 }
1939 while (wl.size() > 0) {
1940 _gvn.transform(wl.pop());
1941 }
1942 }
1943
1944 if (callprojs.fallthrough_catchproj != NULL && !final_ctl->is_top() && do_replaced_nodes) {
1945 replaced_nodes.apply(C, final_ctl);
1946 }
1947 if (!ex_ctl->is_top() && do_replaced_nodes) {
1948 replaced_nodes_exception.apply(C, ex_ctl);
1949 }
1950 }
1951
1952
1953 //------------------------------increment_counter------------------------------
1954 // for statistics: increment a VM counter by 1
1955
1956 void GraphKit::increment_counter(address counter_addr) {
1957 Node* adr1 = makecon(TypeRawPtr::make(counter_addr));
1958 increment_counter(adr1);
1959 }
1960
1961 void GraphKit::increment_counter(Node* counter_addr) {
1962 int adr_type = Compile::AliasIdxRaw;
1963 Node* ctrl = control();
1964 Node* cnt = make_load(ctrl, counter_addr, TypeInt::INT, T_INT, adr_type, MemNode::unordered);
1965 Node* incr = _gvn.transform(new AddINode(cnt, _gvn.intcon(1)));
1966 store_to_memory(ctrl, counter_addr, incr, T_INT, adr_type, MemNode::unordered);
1967 }
1968
1969
1970 //------------------------------uncommon_trap----------------------------------
1971 // Bail out to the interpreter in mid-method. Implemented by calling the
1972 // uncommon_trap blob. This helper function inserts a runtime call with the
1973 // right debug info.
1974 void GraphKit::uncommon_trap(int trap_request,
1975 ciKlass* klass, const char* comment,
1976 bool must_throw,
1977 bool keep_exact_action) {
1978 if (failing()) stop();
1979 if (stopped()) return; // trap reachable?
1980
1981 // Note: If ProfileTraps is true, and if a deopt. actually
1982 // occurs here, the runtime will make sure an MDO exists. There is
1983 // no need to call method()->ensure_method_data() at this point.
1984
1985 // Set the stack pointer to the right value for reexecution:
1986 set_sp(reexecute_sp());
1987
1988 #ifdef ASSERT
1989 if (!must_throw) {
1990 // Make sure the stack has at least enough depth to execute
1991 // the current bytecode.
1992 int inputs, ignored_depth;
1993 if (compute_stack_effects(inputs, ignored_depth)) {
1994 assert(sp() >= inputs, "must have enough JVMS stack to execute %s: sp=%d, inputs=%d",
1995 Bytecodes::name(java_bc()), sp(), inputs);
1996 }
1997 }
1998 #endif
1999
2000 Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
2001 Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
2002
2003 switch (action) {
2004 case Deoptimization::Action_maybe_recompile:
2005 case Deoptimization::Action_reinterpret:
2006 // Temporary fix for 6529811 to allow virtual calls to be sure they
2007 // get the chance to go from mono->bi->mega
2008 if (!keep_exact_action &&
2009 Deoptimization::trap_request_index(trap_request) < 0 &&
2010 too_many_recompiles(reason)) {
2011 // This BCI is causing too many recompilations.
2012 if (C->log() != NULL) {
2013 C->log()->elem("observe that='trap_action_change' reason='%s' from='%s' to='none'",
2014 Deoptimization::trap_reason_name(reason),
2015 Deoptimization::trap_action_name(action));
2016 }
2017 action = Deoptimization::Action_none;
2018 trap_request = Deoptimization::make_trap_request(reason, action);
2019 } else {
2020 C->set_trap_can_recompile(true);
2021 }
2022 break;
2023 case Deoptimization::Action_make_not_entrant:
2024 C->set_trap_can_recompile(true);
2025 break;
2026 case Deoptimization::Action_none:
2027 case Deoptimization::Action_make_not_compilable:
2028 break;
2029 default:
2030 #ifdef ASSERT
2031 fatal("unknown action %d: %s", action, Deoptimization::trap_action_name(action));
2032 #endif
2033 break;
2034 }
2035
2036 if (TraceOptoParse) {
2037 char buf[100];
2038 tty->print_cr("Uncommon trap %s at bci:%d",
2039 Deoptimization::format_trap_request(buf, sizeof(buf),
2040 trap_request), bci());
2041 }
2042
2043 CompileLog* log = C->log();
2044 if (log != NULL) {
2045 int kid = (klass == NULL)? -1: log->identify(klass);
2046 log->begin_elem("uncommon_trap bci='%d'", bci());
2047 char buf[100];
2048 log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf),
2049 trap_request));
2050 if (kid >= 0) log->print(" klass='%d'", kid);
2051 if (comment != NULL) log->print(" comment='%s'", comment);
2052 log->end_elem();
2053 }
2054
2055 // Make sure any guarding test views this path as very unlikely
2056 Node *i0 = control()->in(0);
2057 if (i0 != NULL && i0->is_If()) { // Found a guarding if test?
2058 IfNode *iff = i0->as_If();
2059 float f = iff->_prob; // Get prob
2060 if (control()->Opcode() == Op_IfTrue) {
2061 if (f > PROB_UNLIKELY_MAG(4))
2062 iff->_prob = PROB_MIN;
2063 } else {
2064 if (f < PROB_LIKELY_MAG(4))
2065 iff->_prob = PROB_MAX;
2066 }
2067 }
2068
2069 // Clear out dead values from the debug info.
2070 kill_dead_locals();
2071
2072 // Now insert the uncommon trap subroutine call
2073 address call_addr = SharedRuntime::uncommon_trap_blob()->entry_point();
2074 const TypePtr* no_memory_effects = NULL;
2075 // Pass the index of the class to be loaded
2076 Node* call = make_runtime_call(RC_NO_LEAF | RC_UNCOMMON |
2077 (must_throw ? RC_MUST_THROW : 0),
2078 OptoRuntime::uncommon_trap_Type(),
2079 call_addr, "uncommon_trap", no_memory_effects,
2080 intcon(trap_request));
2081 assert(call->as_CallStaticJava()->uncommon_trap_request() == trap_request,
2082 "must extract request correctly from the graph");
2083 assert(trap_request != 0, "zero value reserved by uncommon_trap_request");
2084
2085 call->set_req(TypeFunc::ReturnAdr, returnadr());
2086 // The debug info is the only real input to this call.
2087
2088 // Halt-and-catch fire here. The above call should never return!
2089 HaltNode* halt = new HaltNode(control(), frameptr());
2090 _gvn.set_type_bottom(halt);
2091 root()->add_req(halt);
2092
2093 stop_and_kill_map();
2094 }
2095
2096
2097 //--------------------------just_allocated_object------------------------------
2098 // Report the object that was just allocated.
2099 // It must be the case that there are no intervening safepoints.
2100 // We use this to determine if an object is so "fresh" that
2101 // it does not require card marks.
2102 Node* GraphKit::just_allocated_object(Node* current_control) {
2103 if (C->recent_alloc_ctl() == current_control)
2104 return C->recent_alloc_obj();
2105 return NULL;
2106 }
2107
2108
2109 void GraphKit::round_double_arguments(ciMethod* dest_method) {
2110 // (Note: TypeFunc::make has a cache that makes this fast.)
2111 const TypeFunc* tf = TypeFunc::make(dest_method);
2112 int nargs = tf->domain()->cnt() - TypeFunc::Parms;
2113 for (int j = 0; j < nargs; j++) {
2114 const Type *targ = tf->domain()->field_at(j + TypeFunc::Parms);
2115 if( targ->basic_type() == T_DOUBLE ) {
2116 // If any parameters are doubles, they must be rounded before
2117 // the call, dstore_rounding does gvn.transform
2118 Node *arg = argument(j);
2119 arg = dstore_rounding(arg);
2120 set_argument(j, arg);
2121 }
2122 }
2123 }
2124
2125 /**
2126 * Record profiling data exact_kls for Node n with the type system so
2127 * that it can propagate it (speculation)
2128 *
2129 * @param n node that the type applies to
2130 * @param exact_kls type from profiling
2131 * @param maybe_null did profiling see null?
2132 *
2133 * @return node with improved type
2134 */
2135 Node* GraphKit::record_profile_for_speculation(Node* n, ciKlass* exact_kls, ProfilePtrKind ptr_kind) {
2136 const Type* current_type = _gvn.type(n);
2137 assert(UseTypeSpeculation, "type speculation must be on");
2138
2139 const TypePtr* speculative = current_type->speculative();
2140
2141 // Should the klass from the profile be recorded in the speculative type?
2142 if (current_type->would_improve_type(exact_kls, jvms()->depth())) {
2143 const TypeKlassPtr* tklass = TypeKlassPtr::make(exact_kls);
2144 const TypeOopPtr* xtype = tklass->as_instance_type();
2145 assert(xtype->klass_is_exact(), "Should be exact");
2146 // Any reason to believe n is not null (from this profiling or a previous one)?
2147 assert(ptr_kind != ProfileAlwaysNull, "impossible here");
2148 const TypePtr* ptr = (ptr_kind == ProfileMaybeNull && current_type->speculative_maybe_null()) ? TypePtr::BOTTOM : TypePtr::NOTNULL;
2149 // record the new speculative type's depth
2150 speculative = xtype->cast_to_ptr_type(ptr->ptr())->is_ptr();
2151 speculative = speculative->with_inline_depth(jvms()->depth());
2152 } else if (current_type->would_improve_ptr(ptr_kind)) {
2153 // Profiling report that null was never seen so we can change the
2154 // speculative type to non null ptr.
2155 if (ptr_kind == ProfileAlwaysNull) {
2156 speculative = TypePtr::NULL_PTR;
2157 } else {
2158 assert(ptr_kind == ProfileNeverNull, "nothing else is an improvement");
2159 const TypePtr* ptr = TypePtr::NOTNULL;
2160 if (speculative != NULL) {
2161 speculative = speculative->cast_to_ptr_type(ptr->ptr())->is_ptr();
2162 } else {
2163 speculative = ptr;
2164 }
2165 }
2166 }
2167
2168 if (speculative != current_type->speculative()) {
2169 // Build a type with a speculative type (what we think we know
2170 // about the type but will need a guard when we use it)
2171 const TypeOopPtr* spec_type = TypeOopPtr::make(TypePtr::BotPTR, Type::OffsetBot, TypeOopPtr::InstanceBot, speculative);
2172 // We're changing the type, we need a new CheckCast node to carry
2173 // the new type. The new type depends on the control: what
2174 // profiling tells us is only valid from here as far as we can
2175 // tell.
2176 Node* cast = new CheckCastPPNode(control(), n, current_type->remove_speculative()->join_speculative(spec_type));
2177 cast = _gvn.transform(cast);
2178 replace_in_map(n, cast);
2179 n = cast;
2180 }
2181
2182 return n;
2183 }
2184
2185 /**
2186 * Record profiling data from receiver profiling at an invoke with the
2187 * type system so that it can propagate it (speculation)
2188 *
2189 * @param n receiver node
2190 *
2191 * @return node with improved type
2192 */
2193 Node* GraphKit::record_profiled_receiver_for_speculation(Node* n) {
2194 if (!UseTypeSpeculation) {
2195 return n;
2196 }
2197 ciKlass* exact_kls = profile_has_unique_klass();
2198 ProfilePtrKind ptr_kind = ProfileMaybeNull;
2199 if ((java_bc() == Bytecodes::_checkcast ||
2200 java_bc() == Bytecodes::_instanceof ||
2201 java_bc() == Bytecodes::_aastore) &&
2202 method()->method_data()->is_mature()) {
2203 ciProfileData* data = method()->method_data()->bci_to_data(bci());
2204 if (data != NULL) {
2205 if (!data->as_BitData()->null_seen()) {
2206 ptr_kind = ProfileNeverNull;
2207 } else {
2208 assert(data->is_ReceiverTypeData(), "bad profile data type");
2209 ciReceiverTypeData* call = (ciReceiverTypeData*)data->as_ReceiverTypeData();
2210 uint i = 0;
2211 for (; i < call->row_limit(); i++) {
2212 ciKlass* receiver = call->receiver(i);
2213 if (receiver != NULL) {
2214 break;
2215 }
2216 }
2217 ptr_kind = (i == call->row_limit()) ? ProfileAlwaysNull : ProfileMaybeNull;
2218 }
2219 }
2220 }
2221 return record_profile_for_speculation(n, exact_kls, ptr_kind);
2222 }
2223
2224 /**
2225 * Record profiling data from argument profiling at an invoke with the
2226 * type system so that it can propagate it (speculation)
2227 *
2228 * @param dest_method target method for the call
2229 * @param bc what invoke bytecode is this?
2230 */
2231 void GraphKit::record_profiled_arguments_for_speculation(ciMethod* dest_method, Bytecodes::Code bc) {
2232 if (!UseTypeSpeculation) {
2233 return;
2234 }
2235 const TypeFunc* tf = TypeFunc::make(dest_method);
2236 int nargs = tf->domain()->cnt() - TypeFunc::Parms;
2237 int skip = Bytecodes::has_receiver(bc) ? 1 : 0;
2238 for (int j = skip, i = 0; j < nargs && i < TypeProfileArgsLimit; j++) {
2239 const Type *targ = tf->domain()->field_at(j + TypeFunc::Parms);
2240 if (targ->basic_type() == T_OBJECT || targ->basic_type() == T_ARRAY) {
2241 ProfilePtrKind ptr_kind = ProfileMaybeNull;
2242 ciKlass* better_type = NULL;
2243 if (method()->argument_profiled_type(bci(), i, better_type, ptr_kind)) {
2244 record_profile_for_speculation(argument(j), better_type, ptr_kind);
2245 }
2246 i++;
2247 }
2248 }
2249 }
2250
2251 /**
2252 * Record profiling data from parameter profiling at an invoke with
2253 * the type system so that it can propagate it (speculation)
2254 */
2255 void GraphKit::record_profiled_parameters_for_speculation() {
2256 if (!UseTypeSpeculation) {
2257 return;
2258 }
2259 for (int i = 0, j = 0; i < method()->arg_size() ; i++) {
2260 if (_gvn.type(local(i))->isa_oopptr()) {
2261 ProfilePtrKind ptr_kind = ProfileMaybeNull;
2262 ciKlass* better_type = NULL;
2263 if (method()->parameter_profiled_type(j, better_type, ptr_kind)) {
2264 record_profile_for_speculation(local(i), better_type, ptr_kind);
2265 }
2266 j++;
2267 }
2268 }
2269 }
2270
2271 /**
2272 * Record profiling data from return value profiling at an invoke with
2273 * the type system so that it can propagate it (speculation)
2274 */
2275 void GraphKit::record_profiled_return_for_speculation() {
2276 if (!UseTypeSpeculation) {
2277 return;
2278 }
2279 ProfilePtrKind ptr_kind = ProfileMaybeNull;
2280 ciKlass* better_type = NULL;
2281 if (method()->return_profiled_type(bci(), better_type, ptr_kind)) {
2282 // If profiling reports a single type for the return value,
2283 // feed it to the type system so it can propagate it as a
2284 // speculative type
2285 record_profile_for_speculation(stack(sp()-1), better_type, ptr_kind);
2286 }
2287 }
2288
2289 void GraphKit::round_double_result(ciMethod* dest_method) {
2290 // A non-strict method may return a double value which has an extended
2291 // exponent, but this must not be visible in a caller which is 'strict'
2292 // If a strict caller invokes a non-strict callee, round a double result
2293
2294 BasicType result_type = dest_method->return_type()->basic_type();
2295 assert( method() != NULL, "must have caller context");
2296 if( result_type == T_DOUBLE && method()->is_strict() && !dest_method->is_strict() ) {
2297 // Destination method's return value is on top of stack
2298 // dstore_rounding() does gvn.transform
2299 Node *result = pop_pair();
2300 result = dstore_rounding(result);
2301 push_pair(result);
2302 }
2303 }
2304
2305 // rounding for strict float precision conformance
2306 Node* GraphKit::precision_rounding(Node* n) {
2307 return UseStrictFP && _method->flags().is_strict()
2308 && UseSSE == 0 && Matcher::strict_fp_requires_explicit_rounding
2309 ? _gvn.transform( new RoundFloatNode(0, n) )
2310 : n;
2311 }
2312
2313 // rounding for strict double precision conformance
2314 Node* GraphKit::dprecision_rounding(Node *n) {
2315 return UseStrictFP && _method->flags().is_strict()
2316 && UseSSE <= 1 && Matcher::strict_fp_requires_explicit_rounding
2317 ? _gvn.transform( new RoundDoubleNode(0, n) )
2318 : n;
2319 }
2320
2321 // rounding for non-strict double stores
2322 Node* GraphKit::dstore_rounding(Node* n) {
2323 return Matcher::strict_fp_requires_explicit_rounding
2324 && UseSSE <= 1
2325 ? _gvn.transform( new RoundDoubleNode(0, n) )
2326 : n;
2327 }
2328
2329 //=============================================================================
2330 // Generate a fast path/slow path idiom. Graph looks like:
2331 // [foo] indicates that 'foo' is a parameter
2332 //
2333 // [in] NULL
2334 // \ /
2335 // CmpP
2336 // Bool ne
2337 // If
2338 // / \
2339 // True False-<2>
2340 // / |
2341 // / cast_not_null
2342 // Load | | ^
2343 // [fast_test] | |
2344 // gvn to opt_test | |
2345 // / \ | <1>
2346 // True False |
2347 // | \\ |
2348 // [slow_call] \[fast_result]
2349 // Ctl Val \ \
2350 // | \ \
2351 // Catch <1> \ \
2352 // / \ ^ \ \
2353 // Ex No_Ex | \ \
2354 // | \ \ | \ <2> \
2355 // ... \ [slow_res] | | \ [null_result]
2356 // \ \--+--+--- | |
2357 // \ | / \ | /
2358 // --------Region Phi
2359 //
2360 //=============================================================================
2361 // Code is structured as a series of driver functions all called 'do_XXX' that
2362 // call a set of helper functions. Helper functions first, then drivers.
2363
2364 //------------------------------null_check_oop---------------------------------
2365 // Null check oop. Set null-path control into Region in slot 3.
2366 // Make a cast-not-nullness use the other not-null control. Return cast.
2367 Node* GraphKit::null_check_oop(Node* value, Node* *null_control,
2368 bool never_see_null,
2369 bool safe_for_replace,
2370 bool speculative) {
2371 // Initial NULL check taken path
2372 (*null_control) = top();
2373 Node* cast = null_check_common(value, T_OBJECT, false, null_control, speculative);
2374
2375 // Generate uncommon_trap:
2376 if (never_see_null && (*null_control) != top()) {
2377 // If we see an unexpected null at a check-cast we record it and force a
2378 // recompile; the offending check-cast will be compiled to handle NULLs.
2379 // If we see more than one offending BCI, then all checkcasts in the
2380 // method will be compiled to handle NULLs.
2381 PreserveJVMState pjvms(this);
2382 set_control(*null_control);
2383 replace_in_map(value, null());
2384 Deoptimization::DeoptReason reason = Deoptimization::reason_null_check(speculative);
2385 uncommon_trap(reason,
2386 Deoptimization::Action_make_not_entrant);
2387 (*null_control) = top(); // NULL path is dead
2388 }
2389 if ((*null_control) == top() && safe_for_replace) {
2390 replace_in_map(value, cast);
2391 }
2392
2393 // Cast away null-ness on the result
2394 return cast;
2395 }
2396
2397 //------------------------------opt_iff----------------------------------------
2398 // Optimize the fast-check IfNode. Set the fast-path region slot 2.
2399 // Return slow-path control.
2400 Node* GraphKit::opt_iff(Node* region, Node* iff) {
2401 IfNode *opt_iff = _gvn.transform(iff)->as_If();
2402
2403 // Fast path taken; set region slot 2
2404 Node *fast_taken = _gvn.transform( new IfFalseNode(opt_iff) );
2405 region->init_req(2,fast_taken); // Capture fast-control
2406
2407 // Fast path not-taken, i.e. slow path
2408 Node *slow_taken = _gvn.transform( new IfTrueNode(opt_iff) );
2409 return slow_taken;
2410 }
2411
2412 //-----------------------------make_runtime_call-------------------------------
2413 Node* GraphKit::make_runtime_call(int flags,
2414 const TypeFunc* call_type, address call_addr,
2415 const char* call_name,
2416 const TypePtr* adr_type,
2417 // The following parms are all optional.
2418 // The first NULL ends the list.
2419 Node* parm0, Node* parm1,
2420 Node* parm2, Node* parm3,
2421 Node* parm4, Node* parm5,
2422 Node* parm6, Node* parm7) {
2423 // Slow-path call
2424 bool is_leaf = !(flags & RC_NO_LEAF);
2425 bool has_io = (!is_leaf && !(flags & RC_NO_IO));
2426 if (call_name == NULL) {
2427 assert(!is_leaf, "must supply name for leaf");
2428 call_name = OptoRuntime::stub_name(call_addr);
2429 }
2430 CallNode* call;
2431 if (!is_leaf) {
2432 call = new CallStaticJavaNode(call_type, call_addr, call_name,
2433 bci(), adr_type);
2434 } else if (flags & RC_NO_FP) {
2435 call = new CallLeafNoFPNode(call_type, call_addr, call_name, adr_type);
2436 } else {
2437 call = new CallLeafNode(call_type, call_addr, call_name, adr_type);
2438 }
2439
2440 // The following is similar to set_edges_for_java_call,
2441 // except that the memory effects of the call are restricted to AliasIdxRaw.
2442
2443 // Slow path call has no side-effects, uses few values
2444 bool wide_in = !(flags & RC_NARROW_MEM);
2445 bool wide_out = (C->get_alias_index(adr_type) == Compile::AliasIdxBot);
2446
2447 Node* prev_mem = NULL;
2448 if (wide_in) {
2449 prev_mem = set_predefined_input_for_runtime_call(call);
2450 } else {
2451 assert(!wide_out, "narrow in => narrow out");
2452 Node* narrow_mem = memory(adr_type);
2453 prev_mem = reset_memory();
2454 map()->set_memory(narrow_mem);
2455 set_predefined_input_for_runtime_call(call);
2456 }
2457
2458 // Hook each parm in order. Stop looking at the first NULL.
2459 if (parm0 != NULL) { call->init_req(TypeFunc::Parms+0, parm0);
2460 if (parm1 != NULL) { call->init_req(TypeFunc::Parms+1, parm1);
2461 if (parm2 != NULL) { call->init_req(TypeFunc::Parms+2, parm2);
2462 if (parm3 != NULL) { call->init_req(TypeFunc::Parms+3, parm3);
2463 if (parm4 != NULL) { call->init_req(TypeFunc::Parms+4, parm4);
2464 if (parm5 != NULL) { call->init_req(TypeFunc::Parms+5, parm5);
2465 if (parm6 != NULL) { call->init_req(TypeFunc::Parms+6, parm6);
2466 if (parm7 != NULL) { call->init_req(TypeFunc::Parms+7, parm7);
2467 /* close each nested if ===> */ } } } } } } } }
2468 assert(call->in(call->req()-1) != NULL, "must initialize all parms");
2469
2470 if (!is_leaf) {
2471 // Non-leaves can block and take safepoints:
2472 add_safepoint_edges(call, ((flags & RC_MUST_THROW) != 0));
2473 }
2474 // Non-leaves can throw exceptions:
2475 if (has_io) {
2476 call->set_req(TypeFunc::I_O, i_o());
2477 }
2478
2479 if (flags & RC_UNCOMMON) {
2480 // Set the count to a tiny probability. Cf. Estimate_Block_Frequency.
2481 // (An "if" probability corresponds roughly to an unconditional count.
2482 // Sort of.)
2483 call->set_cnt(PROB_UNLIKELY_MAG(4));
2484 }
2485
2486 Node* c = _gvn.transform(call);
2487 assert(c == call, "cannot disappear");
2488
2489 if (wide_out) {
2490 // Slow path call has full side-effects.
2491 set_predefined_output_for_runtime_call(call);
2492 } else {
2493 // Slow path call has few side-effects, and/or sets few values.
2494 set_predefined_output_for_runtime_call(call, prev_mem, adr_type);
2495 }
2496
2497 if (has_io) {
2498 set_i_o(_gvn.transform(new ProjNode(call, TypeFunc::I_O)));
2499 }
2500 return call;
2501
2502 }
2503
2504 //------------------------------merge_memory-----------------------------------
2505 // Merge memory from one path into the current memory state.
2506 void GraphKit::merge_memory(Node* new_mem, Node* region, int new_path) {
2507 for (MergeMemStream mms(merged_memory(), new_mem->as_MergeMem()); mms.next_non_empty2(); ) {
2508 Node* old_slice = mms.force_memory();
2509 Node* new_slice = mms.memory2();
2510 if (old_slice != new_slice) {
2511 PhiNode* phi;
2512 if (old_slice->is_Phi() && old_slice->as_Phi()->region() == region) {
2513 if (mms.is_empty()) {
2514 // clone base memory Phi's inputs for this memory slice
2515 assert(old_slice == mms.base_memory(), "sanity");
2516 phi = PhiNode::make(region, NULL, Type::MEMORY, mms.adr_type(C));
2517 _gvn.set_type(phi, Type::MEMORY);
2518 for (uint i = 1; i < phi->req(); i++) {
2519 phi->init_req(i, old_slice->in(i));
2520 }
2521 } else {
2522 phi = old_slice->as_Phi(); // Phi was generated already
2523 }
2524 } else {
2525 phi = PhiNode::make(region, old_slice, Type::MEMORY, mms.adr_type(C));
2526 _gvn.set_type(phi, Type::MEMORY);
2527 }
2528 phi->set_req(new_path, new_slice);
2529 mms.set_memory(phi);
2530 }
2531 }
2532 }
2533
2534 //------------------------------make_slow_call_ex------------------------------
2535 // Make the exception handler hookups for the slow call
2536 void GraphKit::make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj, bool deoptimize) {
2537 if (stopped()) return;
2538
2539 // Make a catch node with just two handlers: fall-through and catch-all
2540 Node* i_o = _gvn.transform( new ProjNode(call, TypeFunc::I_O, separate_io_proj) );
2541 Node* catc = _gvn.transform( new CatchNode(control(), i_o, 2) );
2542 Node* norm = _gvn.transform( new CatchProjNode(catc, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci) );
2543 Node* excp = _gvn.transform( new CatchProjNode(catc, CatchProjNode::catch_all_index, CatchProjNode::no_handler_bci) );
2544
2545 { PreserveJVMState pjvms(this);
2546 set_control(excp);
2547 set_i_o(i_o);
2548
2549 if (excp != top()) {
2550 if (deoptimize) {
2551 // Deoptimize if an exception is caught. Don't construct exception state in this case.
2552 uncommon_trap(Deoptimization::Reason_unhandled,
2553 Deoptimization::Action_none);
2554 } else {
2555 // Create an exception state also.
2556 // Use an exact type if the caller has specified a specific exception.
2557 const Type* ex_type = TypeOopPtr::make_from_klass_unique(ex_klass)->cast_to_ptr_type(TypePtr::NotNull);
2558 Node* ex_oop = new CreateExNode(ex_type, control(), i_o);
2559 add_exception_state(make_exception_state(_gvn.transform(ex_oop)));
2560 }
2561 }
2562 }
2563
2564 // Get the no-exception control from the CatchNode.
2565 set_control(norm);
2566 }
2567
2568 static IfNode* gen_subtype_check_compare(Node* ctrl, Node* in1, Node* in2, BoolTest::mask test, float p, PhaseGVN* gvn, BasicType bt) {
2569 Node* cmp = NULL;
2570 switch(bt) {
2571 case T_INT: cmp = new CmpINode(in1, in2); break;
2572 case T_ADDRESS: cmp = new CmpPNode(in1, in2); break;
2573 default: fatal("unexpected comparison type %s", type2name(bt));
2574 }
2575 gvn->transform(cmp);
2576 Node* bol = gvn->transform(new BoolNode(cmp, test));
2577 IfNode* iff = new IfNode(ctrl, bol, p, COUNT_UNKNOWN);
2578 gvn->transform(iff);
2579 if (!bol->is_Con()) gvn->record_for_igvn(iff);
2580 return iff;
2581 }
2582
2583
2584 //-------------------------------gen_subtype_check-----------------------------
2585 // Generate a subtyping check. Takes as input the subtype and supertype.
2586 // Returns 2 values: sets the default control() to the true path and returns
2587 // the false path. Only reads invariant memory; sets no (visible) memory.
2588 // The PartialSubtypeCheckNode sets the hidden 1-word cache in the encoding
2589 // but that's not exposed to the optimizer. This call also doesn't take in an
2590 // Object; if you wish to check an Object you need to load the Object's class
2591 // prior to coming here.
2592 Node* Phase::gen_subtype_check(Node* subklass, Node* superklass, Node** ctrl, MergeMemNode* mem, PhaseGVN* gvn) {
2593 Compile* C = gvn->C;
2594
2595 if ((*ctrl)->is_top()) {
2596 return C->top();
2597 }
2598
2599 // Fast check for identical types, perhaps identical constants.
2600 // The types can even be identical non-constants, in cases
2601 // involving Array.newInstance, Object.clone, etc.
2602 if (subklass == superklass)
2603 return C->top(); // false path is dead; no test needed.
2604
2605 if (gvn->type(superklass)->singleton()) {
2606 ciKlass* superk = gvn->type(superklass)->is_klassptr()->klass();
2607 ciKlass* subk = gvn->type(subklass)->is_klassptr()->klass();
2608
2609 // In the common case of an exact superklass, try to fold up the
2610 // test before generating code. You may ask, why not just generate
2611 // the code and then let it fold up? The answer is that the generated
2612 // code will necessarily include null checks, which do not always
2613 // completely fold away. If they are also needless, then they turn
2614 // into a performance loss. Example:
2615 // Foo[] fa = blah(); Foo x = fa[0]; fa[1] = x;
2616 // Here, the type of 'fa' is often exact, so the store check
2617 // of fa[1]=x will fold up, without testing the nullness of x.
2618 switch (C->static_subtype_check(superk, subk)) {
2619 case Compile::SSC_always_false:
2620 {
2621 Node* always_fail = *ctrl;
2622 *ctrl = gvn->C->top();
2623 return always_fail;
2624 }
2625 case Compile::SSC_always_true:
2626 return C->top();
2627 case Compile::SSC_easy_test:
2628 {
2629 // Just do a direct pointer compare and be done.
2630 IfNode* iff = gen_subtype_check_compare(*ctrl, subklass, superklass, BoolTest::eq, PROB_STATIC_FREQUENT, gvn, T_ADDRESS);
2631 *ctrl = gvn->transform(new IfTrueNode(iff));
2632 return gvn->transform(new IfFalseNode(iff));
2633 }
2634 case Compile::SSC_full_test:
2635 break;
2636 default:
2637 ShouldNotReachHere();
2638 }
2639 }
2640
2641 // %%% Possible further optimization: Even if the superklass is not exact,
2642 // if the subklass is the unique subtype of the superklass, the check
2643 // will always succeed. We could leave a dependency behind to ensure this.
2644
2645 // First load the super-klass's check-offset
2646 Node *p1 = gvn->transform(new AddPNode(superklass, superklass, gvn->MakeConX(in_bytes(Klass::super_check_offset_offset()))));
2647 Node* m = mem->memory_at(C->get_alias_index(gvn->type(p1)->is_ptr()));
2648 Node *chk_off = gvn->transform(new LoadINode(NULL, m, p1, gvn->type(p1)->is_ptr(), TypeInt::INT, MemNode::unordered));
2649 int cacheoff_con = in_bytes(Klass::secondary_super_cache_offset());
2650 bool might_be_cache = (gvn->find_int_con(chk_off, cacheoff_con) == cacheoff_con);
2651
2652 // Load from the sub-klass's super-class display list, or a 1-word cache of
2653 // the secondary superclass list, or a failing value with a sentinel offset
2654 // if the super-klass is an interface or exceptionally deep in the Java
2655 // hierarchy and we have to scan the secondary superclass list the hard way.
2656 // Worst-case type is a little odd: NULL is allowed as a result (usually
2657 // klass loads can never produce a NULL).
2658 Node *chk_off_X = chk_off;
2659 #ifdef _LP64
2660 chk_off_X = gvn->transform(new ConvI2LNode(chk_off_X));
2661 #endif
2662 Node *p2 = gvn->transform(new AddPNode(subklass,subklass,chk_off_X));
2663 // For some types like interfaces the following loadKlass is from a 1-word
2664 // cache which is mutable so can't use immutable memory. Other
2665 // types load from the super-class display table which is immutable.
2666 m = mem->memory_at(C->get_alias_index(gvn->type(p2)->is_ptr()));
2667 Node *kmem = might_be_cache ? m : C->immutable_memory();
2668 Node *nkls = gvn->transform(LoadKlassNode::make(*gvn, NULL, kmem, p2, gvn->type(p2)->is_ptr(), TypeKlassPtr::OBJECT_OR_NULL));
2669
2670 // Compile speed common case: ARE a subtype and we canNOT fail
2671 if( superklass == nkls )
2672 return C->top(); // false path is dead; no test needed.
2673
2674 // See if we get an immediate positive hit. Happens roughly 83% of the
2675 // time. Test to see if the value loaded just previously from the subklass
2676 // is exactly the superklass.
2677 IfNode *iff1 = gen_subtype_check_compare(*ctrl, superklass, nkls, BoolTest::eq, PROB_LIKELY(0.83f), gvn, T_ADDRESS);
2678 Node *iftrue1 = gvn->transform( new IfTrueNode (iff1));
2679 *ctrl = gvn->transform(new IfFalseNode(iff1));
2680
2681 // Compile speed common case: Check for being deterministic right now. If
2682 // chk_off is a constant and not equal to cacheoff then we are NOT a
2683 // subklass. In this case we need exactly the 1 test above and we can
2684 // return those results immediately.
2685 if (!might_be_cache) {
2686 Node* not_subtype_ctrl = *ctrl;
2687 *ctrl = iftrue1; // We need exactly the 1 test above
2688 return not_subtype_ctrl;
2689 }
2690
2691 // Gather the various success & failures here
2692 RegionNode *r_ok_subtype = new RegionNode(4);
2693 gvn->record_for_igvn(r_ok_subtype);
2694 RegionNode *r_not_subtype = new RegionNode(3);
2695 gvn->record_for_igvn(r_not_subtype);
2696
2697 r_ok_subtype->init_req(1, iftrue1);
2698
2699 // Check for immediate negative hit. Happens roughly 11% of the time (which
2700 // is roughly 63% of the remaining cases). Test to see if the loaded
2701 // check-offset points into the subklass display list or the 1-element
2702 // cache. If it points to the display (and NOT the cache) and the display
2703 // missed then it's not a subtype.
2704 Node *cacheoff = gvn->intcon(cacheoff_con);
2705 IfNode *iff2 = gen_subtype_check_compare(*ctrl, chk_off, cacheoff, BoolTest::ne, PROB_LIKELY(0.63f), gvn, T_INT);
2706 r_not_subtype->init_req(1, gvn->transform(new IfTrueNode (iff2)));
2707 *ctrl = gvn->transform(new IfFalseNode(iff2));
2708
2709 // Check for self. Very rare to get here, but it is taken 1/3 the time.
2710 // No performance impact (too rare) but allows sharing of secondary arrays
2711 // which has some footprint reduction.
2712 IfNode *iff3 = gen_subtype_check_compare(*ctrl, subklass, superklass, BoolTest::eq, PROB_LIKELY(0.36f), gvn, T_ADDRESS);
2713 r_ok_subtype->init_req(2, gvn->transform(new IfTrueNode(iff3)));
2714 *ctrl = gvn->transform(new IfFalseNode(iff3));
2715
2716 // -- Roads not taken here: --
2717 // We could also have chosen to perform the self-check at the beginning
2718 // of this code sequence, as the assembler does. This would not pay off
2719 // the same way, since the optimizer, unlike the assembler, can perform
2720 // static type analysis to fold away many successful self-checks.
2721 // Non-foldable self checks work better here in second position, because
2722 // the initial primary superclass check subsumes a self-check for most
2723 // types. An exception would be a secondary type like array-of-interface,
2724 // which does not appear in its own primary supertype display.
2725 // Finally, we could have chosen to move the self-check into the
2726 // PartialSubtypeCheckNode, and from there out-of-line in a platform
2727 // dependent manner. But it is worthwhile to have the check here,
2728 // where it can be perhaps be optimized. The cost in code space is
2729 // small (register compare, branch).
2730
2731 // Now do a linear scan of the secondary super-klass array. Again, no real
2732 // performance impact (too rare) but it's gotta be done.
2733 // Since the code is rarely used, there is no penalty for moving it
2734 // out of line, and it can only improve I-cache density.
2735 // The decision to inline or out-of-line this final check is platform
2736 // dependent, and is found in the AD file definition of PartialSubtypeCheck.
2737 Node* psc = gvn->transform(
2738 new PartialSubtypeCheckNode(*ctrl, subklass, superklass));
2739
2740 IfNode *iff4 = gen_subtype_check_compare(*ctrl, psc, gvn->zerocon(T_OBJECT), BoolTest::ne, PROB_FAIR, gvn, T_ADDRESS);
2741 r_not_subtype->init_req(2, gvn->transform(new IfTrueNode (iff4)));
2742 r_ok_subtype ->init_req(3, gvn->transform(new IfFalseNode(iff4)));
2743
2744 // Return false path; set default control to true path.
2745 *ctrl = gvn->transform(r_ok_subtype);
2746 return gvn->transform(r_not_subtype);
2747 }
2748
2749 // Profile-driven exact type check:
2750 Node* GraphKit::type_check_receiver(Node* receiver, ciKlass* klass,
2751 float prob,
2752 Node* *casted_receiver) {
2753 const TypeKlassPtr* tklass = TypeKlassPtr::make(klass);
2754 Node* recv_klass = load_object_klass(receiver);
2755 Node* want_klass = makecon(tklass);
2756 Node* cmp = _gvn.transform( new CmpPNode(recv_klass, want_klass) );
2757 Node* bol = _gvn.transform( new BoolNode(cmp, BoolTest::eq) );
2758 IfNode* iff = create_and_xform_if(control(), bol, prob, COUNT_UNKNOWN);
2759 set_control( _gvn.transform( new IfTrueNode (iff) ));
2760 Node* fail = _gvn.transform( new IfFalseNode(iff) );
2761
2762 const TypeOopPtr* recv_xtype = tklass->as_instance_type();
2763 assert(recv_xtype->klass_is_exact(), "");
2764
2765 // Subsume downstream occurrences of receiver with a cast to
2766 // recv_xtype, since now we know what the type will be.
2767 Node* cast = new CheckCastPPNode(control(), receiver, recv_xtype);
2768 (*casted_receiver) = _gvn.transform(cast);
2769 // (User must make the replace_in_map call.)
2770
2771 return fail;
2772 }
2773
2774
2775 //------------------------------seems_never_null-------------------------------
2776 // Use null_seen information if it is available from the profile.
2777 // If we see an unexpected null at a type check we record it and force a
2778 // recompile; the offending check will be recompiled to handle NULLs.
2779 // If we see several offending BCIs, then all checks in the
2780 // method will be recompiled.
2781 bool GraphKit::seems_never_null(Node* obj, ciProfileData* data, bool& speculating) {
2782 speculating = !_gvn.type(obj)->speculative_maybe_null();
2783 Deoptimization::DeoptReason reason = Deoptimization::reason_null_check(speculating);
2784 if (UncommonNullCast // Cutout for this technique
2785 && obj != null() // And not the -Xcomp stupid case?
2786 && !too_many_traps(reason)
2787 ) {
2788 if (speculating) {
2789 return true;
2790 }
2791 if (data == NULL)
2792 // Edge case: no mature data. Be optimistic here.
2793 return true;
2794 // If the profile has not seen a null, assume it won't happen.
2795 assert(java_bc() == Bytecodes::_checkcast ||
2796 java_bc() == Bytecodes::_instanceof ||
2797 java_bc() == Bytecodes::_aastore, "MDO must collect null_seen bit here");
2798 return !data->as_BitData()->null_seen();
2799 }
2800 speculating = false;
2801 return false;
2802 }
2803
2804 //------------------------maybe_cast_profiled_receiver-------------------------
2805 // If the profile has seen exactly one type, narrow to exactly that type.
2806 // Subsequent type checks will always fold up.
2807 Node* GraphKit::maybe_cast_profiled_receiver(Node* not_null_obj,
2808 ciKlass* require_klass,
2809 ciKlass* spec_klass,
2810 bool safe_for_replace) {
2811 if (!UseTypeProfile || !TypeProfileCasts) return NULL;
2812
2813 Deoptimization::DeoptReason reason = Deoptimization::reason_class_check(spec_klass != NULL);
2814
2815 // Make sure we haven't already deoptimized from this tactic.
2816 if (too_many_traps(reason) || too_many_recompiles(reason))
2817 return NULL;
2818
2819 // (No, this isn't a call, but it's enough like a virtual call
2820 // to use the same ciMethod accessor to get the profile info...)
2821 // If we have a speculative type use it instead of profiling (which
2822 // may not help us)
2823 ciKlass* exact_kls = spec_klass == NULL ? profile_has_unique_klass() : spec_klass;
2824 if (exact_kls != NULL) {// no cast failures here
2825 if (require_klass == NULL ||
2826 C->static_subtype_check(require_klass, exact_kls) == Compile::SSC_always_true) {
2827 // If we narrow the type to match what the type profile sees or
2828 // the speculative type, we can then remove the rest of the
2829 // cast.
2830 // This is a win, even if the exact_kls is very specific,
2831 // because downstream operations, such as method calls,
2832 // will often benefit from the sharper type.
2833 Node* exact_obj = not_null_obj; // will get updated in place...
2834 Node* slow_ctl = type_check_receiver(exact_obj, exact_kls, 1.0,
2835 &exact_obj);
2836 { PreserveJVMState pjvms(this);
2837 set_control(slow_ctl);
2838 uncommon_trap_exact(reason, Deoptimization::Action_maybe_recompile);
2839 }
2840 if (safe_for_replace) {
2841 replace_in_map(not_null_obj, exact_obj);
2842 }
2843 return exact_obj;
2844 }
2845 // assert(ssc == Compile::SSC_always_true)... except maybe the profile lied to us.
2846 }
2847
2848 return NULL;
2849 }
2850
2851 /**
2852 * Cast obj to type and emit guard unless we had too many traps here
2853 * already
2854 *
2855 * @param obj node being casted
2856 * @param type type to cast the node to
2857 * @param not_null true if we know node cannot be null
2858 */
2859 Node* GraphKit::maybe_cast_profiled_obj(Node* obj,
2860 ciKlass* type,
2861 bool not_null) {
2862 if (stopped()) {
2863 return obj;
2864 }
2865
2866 // type == NULL if profiling tells us this object is always null
2867 if (type != NULL) {
2868 Deoptimization::DeoptReason class_reason = Deoptimization::Reason_speculate_class_check;
2869 Deoptimization::DeoptReason null_reason = Deoptimization::Reason_speculate_null_check;
2870
2871 if (!too_many_traps(null_reason) && !too_many_recompiles(null_reason) &&
2872 !too_many_traps(class_reason) &&
2873 !too_many_recompiles(class_reason)) {
2874 Node* not_null_obj = NULL;
2875 // not_null is true if we know the object is not null and
2876 // there's no need for a null check
2877 if (!not_null) {
2878 Node* null_ctl = top();
2879 not_null_obj = null_check_oop(obj, &null_ctl, true, true, true);
2880 assert(null_ctl->is_top(), "no null control here");
2881 } else {
2882 not_null_obj = obj;
2883 }
2884
2885 Node* exact_obj = not_null_obj;
2886 ciKlass* exact_kls = type;
2887 Node* slow_ctl = type_check_receiver(exact_obj, exact_kls, 1.0,
2888 &exact_obj);
2889 {
2890 PreserveJVMState pjvms(this);
2891 set_control(slow_ctl);
2892 uncommon_trap_exact(class_reason, Deoptimization::Action_maybe_recompile);
2893 }
2894 replace_in_map(not_null_obj, exact_obj);
2895 obj = exact_obj;
2896 }
2897 } else {
2898 if (!too_many_traps(Deoptimization::Reason_null_assert) &&
2899 !too_many_recompiles(Deoptimization::Reason_null_assert)) {
2900 Node* exact_obj = null_assert(obj);
2901 replace_in_map(obj, exact_obj);
2902 obj = exact_obj;
2903 }
2904 }
2905 return obj;
2906 }
2907
2908 //-------------------------------gen_instanceof--------------------------------
2909 // Generate an instance-of idiom. Used by both the instance-of bytecode
2910 // and the reflective instance-of call.
2911 Node* GraphKit::gen_instanceof(Node* obj, Node* superklass, bool safe_for_replace) {
2912 kill_dead_locals(); // Benefit all the uncommon traps
2913 assert( !stopped(), "dead parse path should be checked in callers" );
2914 assert(!TypePtr::NULL_PTR->higher_equal(_gvn.type(superklass)->is_klassptr()),
2915 "must check for not-null not-dead klass in callers");
2916
2917 // Make the merge point
2918 enum { _obj_path = 1, _fail_path, _null_path, PATH_LIMIT };
2919 RegionNode* region = new RegionNode(PATH_LIMIT);
2920 Node* phi = new PhiNode(region, TypeInt::BOOL);
2921 C->set_has_split_ifs(true); // Has chance for split-if optimization
2922
2923 ciProfileData* data = NULL;
2924 if (java_bc() == Bytecodes::_instanceof) { // Only for the bytecode
2925 data = method()->method_data()->bci_to_data(bci());
2926 }
2927 bool speculative_not_null = false;
2928 bool never_see_null = (ProfileDynamicTypes // aggressive use of profile
2929 && seems_never_null(obj, data, speculative_not_null));
2930
2931 // Null check; get casted pointer; set region slot 3
2932 Node* null_ctl = top();
2933 Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace, speculative_not_null);
2934
2935 // If not_null_obj is dead, only null-path is taken
2936 if (stopped()) { // Doing instance-of on a NULL?
2937 set_control(null_ctl);
2938 return intcon(0);
2939 }
2940 region->init_req(_null_path, null_ctl);
2941 phi ->init_req(_null_path, intcon(0)); // Set null path value
2942 if (null_ctl == top()) {
2943 // Do this eagerly, so that pattern matches like is_diamond_phi
2944 // will work even during parsing.
2945 assert(_null_path == PATH_LIMIT-1, "delete last");
2946 region->del_req(_null_path);
2947 phi ->del_req(_null_path);
2948 }
2949
2950 // Do we know the type check always succeed?
2951 bool known_statically = false;
2952 if (_gvn.type(superklass)->singleton()) {
2953 ciKlass* superk = _gvn.type(superklass)->is_klassptr()->klass();
2954 ciKlass* subk = _gvn.type(obj)->is_oopptr()->klass();
2955 if (subk != NULL && subk->is_loaded()) {
2956 int static_res = C->static_subtype_check(superk, subk);
2957 known_statically = (static_res == Compile::SSC_always_true || static_res == Compile::SSC_always_false);
2958 }
2959 }
2960
2961 if (!known_statically) {
2962 const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
2963 // We may not have profiling here or it may not help us. If we
2964 // have a speculative type use it to perform an exact cast.
2965 ciKlass* spec_obj_type = obj_type->speculative_type();
2966 if (spec_obj_type != NULL || (ProfileDynamicTypes && data != NULL)) {
2967 Node* cast_obj = maybe_cast_profiled_receiver(not_null_obj, NULL, spec_obj_type, safe_for_replace);
2968 if (stopped()) { // Profile disagrees with this path.
2969 set_control(null_ctl); // Null is the only remaining possibility.
2970 return intcon(0);
2971 }
2972 if (cast_obj != NULL) {
2973 not_null_obj = cast_obj;
2974 }
2975 }
2976 }
2977
2978 // Load the object's klass
2979 Node* obj_klass = load_object_klass(not_null_obj);
2980
2981 // Generate the subtype check
2982 Node* not_subtype_ctrl = gen_subtype_check(obj_klass, superklass);
2983
2984 // Plug in the success path to the general merge in slot 1.
2985 region->init_req(_obj_path, control());
2986 phi ->init_req(_obj_path, intcon(1));
2987
2988 // Plug in the failing path to the general merge in slot 2.
2989 region->init_req(_fail_path, not_subtype_ctrl);
2990 phi ->init_req(_fail_path, intcon(0));
2991
2992 // Return final merged results
2993 set_control( _gvn.transform(region) );
2994 record_for_igvn(region);
2995
2996 // If we know the type check always succeeds then we don't use the
2997 // profiling data at this bytecode. Don't lose it, feed it to the
2998 // type system as a speculative type.
2999 if (safe_for_replace) {
3000 Node* casted_obj = record_profiled_receiver_for_speculation(obj);
3001 replace_in_map(obj, casted_obj);
3002 }
3003
3004 return _gvn.transform(phi);
3005 }
3006
3007 //-------------------------------gen_checkcast---------------------------------
3008 // Generate a checkcast idiom. Used by both the checkcast bytecode and the
3009 // array store bytecode. Stack must be as-if BEFORE doing the bytecode so the
3010 // uncommon-trap paths work. Adjust stack after this call.
3011 // If failure_control is supplied and not null, it is filled in with
3012 // the control edge for the cast failure. Otherwise, an appropriate
3013 // uncommon trap or exception is thrown.
3014 Node* GraphKit::gen_checkcast(Node *obj, Node* superklass,
3015 Node* *failure_control) {
3016 kill_dead_locals(); // Benefit all the uncommon traps
3017 const TypeKlassPtr *tk = _gvn.type(superklass)->is_klassptr();
3018 const Type *toop = TypeOopPtr::make_from_klass(tk->klass());
3019
3020 // Fast cutout: Check the case that the cast is vacuously true.
3021 // This detects the common cases where the test will short-circuit
3022 // away completely. We do this before we perform the null check,
3023 // because if the test is going to turn into zero code, we don't
3024 // want a residual null check left around. (Causes a slowdown,
3025 // for example, in some objArray manipulations, such as a[i]=a[j].)
3026 if (tk->singleton()) {
3027 const TypeOopPtr* objtp = _gvn.type(obj)->isa_oopptr();
3028 if (objtp != NULL && objtp->klass() != NULL) {
3029 switch (C->static_subtype_check(tk->klass(), objtp->klass())) {
3030 case Compile::SSC_always_true:
3031 // If we know the type check always succeed then we don't use
3032 // the profiling data at this bytecode. Don't lose it, feed it
3033 // to the type system as a speculative type.
3034 return record_profiled_receiver_for_speculation(obj);
3035 case Compile::SSC_always_false:
3036 // It needs a null check because a null will *pass* the cast check.
3037 // A non-null value will always produce an exception.
3038 return null_assert(obj);
3039 }
3040 }
3041 }
3042
3043 ciProfileData* data = NULL;
3044 bool safe_for_replace = false;
3045 if (failure_control == NULL) { // use MDO in regular case only
3046 assert(java_bc() == Bytecodes::_aastore ||
3047 java_bc() == Bytecodes::_checkcast,
3048 "interpreter profiles type checks only for these BCs");
3049 data = method()->method_data()->bci_to_data(bci());
3050 safe_for_replace = true;
3051 }
3052
3053 // Make the merge point
3054 enum { _obj_path = 1, _null_path, PATH_LIMIT };
3055 RegionNode* region = new RegionNode(PATH_LIMIT);
3056 Node* phi = new PhiNode(region, toop);
3057 C->set_has_split_ifs(true); // Has chance for split-if optimization
3058
3059 // Use null-cast information if it is available
3060 bool speculative_not_null = false;
3061 bool never_see_null = ((failure_control == NULL) // regular case only
3062 && seems_never_null(obj, data, speculative_not_null));
3063
3064 // Null check; get casted pointer; set region slot 3
3065 Node* null_ctl = top();
3066 Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace, speculative_not_null);
3067
3068 // If not_null_obj is dead, only null-path is taken
3069 if (stopped()) { // Doing instance-of on a NULL?
3070 set_control(null_ctl);
3071 return null();
3072 }
3073 region->init_req(_null_path, null_ctl);
3074 phi ->init_req(_null_path, null()); // Set null path value
3075 if (null_ctl == top()) {
3076 // Do this eagerly, so that pattern matches like is_diamond_phi
3077 // will work even during parsing.
3078 assert(_null_path == PATH_LIMIT-1, "delete last");
3079 region->del_req(_null_path);
3080 phi ->del_req(_null_path);
3081 }
3082
3083 Node* cast_obj = NULL;
3084 if (tk->klass_is_exact()) {
3085 // The following optimization tries to statically cast the speculative type of the object
3086 // (for example obtained during profiling) to the type of the superklass and then do a
3087 // dynamic check that the type of the object is what we expect. To work correctly
3088 // for checkcast and aastore the type of superklass should be exact.
3089 const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
3090 // We may not have profiling here or it may not help us. If we have
3091 // a speculative type use it to perform an exact cast.
3092 ciKlass* spec_obj_type = obj_type->speculative_type();
3093 if (spec_obj_type != NULL || data != NULL) {
3094 cast_obj = maybe_cast_profiled_receiver(not_null_obj, tk->klass(), spec_obj_type, safe_for_replace);
3095 if (cast_obj != NULL) {
3096 if (failure_control != NULL) // failure is now impossible
3097 (*failure_control) = top();
3098 // adjust the type of the phi to the exact klass:
3099 phi->raise_bottom_type(_gvn.type(cast_obj)->meet_speculative(TypePtr::NULL_PTR));
3100 }
3101 }
3102 }
3103
3104 if (cast_obj == NULL) {
3105 // Load the object's klass
3106 Node* obj_klass = load_object_klass(not_null_obj);
3107
3108 // Generate the subtype check
3109 Node* not_subtype_ctrl = gen_subtype_check( obj_klass, superklass );
3110
3111 // Plug in success path into the merge
3112 cast_obj = _gvn.transform(new CheckCastPPNode(control(), not_null_obj, toop));
3113 // Failure path ends in uncommon trap (or may be dead - failure impossible)
3114 if (failure_control == NULL) {
3115 if (not_subtype_ctrl != top()) { // If failure is possible
3116 PreserveJVMState pjvms(this);
3117 set_control(not_subtype_ctrl);
3118 builtin_throw(Deoptimization::Reason_class_check, obj_klass);
3119 }
3120 } else {
3121 (*failure_control) = not_subtype_ctrl;
3122 }
3123 }
3124
3125 region->init_req(_obj_path, control());
3126 phi ->init_req(_obj_path, cast_obj);
3127
3128 // A merge of NULL or Casted-NotNull obj
3129 Node* res = _gvn.transform(phi);
3130
3131 // Note I do NOT always 'replace_in_map(obj,result)' here.
3132 // if( tk->klass()->can_be_primary_super() )
3133 // This means that if I successfully store an Object into an array-of-String
3134 // I 'forget' that the Object is really now known to be a String. I have to
3135 // do this because we don't have true union types for interfaces - if I store
3136 // a Baz into an array-of-Interface and then tell the optimizer it's an
3137 // Interface, I forget that it's also a Baz and cannot do Baz-like field
3138 // references to it. FIX THIS WHEN UNION TYPES APPEAR!
3139 // replace_in_map( obj, res );
3140
3141 // Return final merged results
3142 set_control( _gvn.transform(region) );
3143 record_for_igvn(region);
3144
3145 return record_profiled_receiver_for_speculation(res);
3146 }
3147
3148 //------------------------------next_monitor-----------------------------------
3149 // What number should be given to the next monitor?
3150 int GraphKit::next_monitor() {
3151 int current = jvms()->monitor_depth()* C->sync_stack_slots();
3152 int next = current + C->sync_stack_slots();
3153 // Keep the toplevel high water mark current:
3154 if (C->fixed_slots() < next) C->set_fixed_slots(next);
3155 return current;
3156 }
3157
3158 //------------------------------insert_mem_bar---------------------------------
3159 // Memory barrier to avoid floating things around
3160 // The membar serves as a pinch point between both control and all memory slices.
3161 Node* GraphKit::insert_mem_bar(int opcode, Node* precedent) {
3162 MemBarNode* mb = MemBarNode::make(C, opcode, Compile::AliasIdxBot, precedent);
3163 mb->init_req(TypeFunc::Control, control());
3164 mb->init_req(TypeFunc::Memory, reset_memory());
3165 Node* membar = _gvn.transform(mb);
3166 set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control)));
3167 set_all_memory_call(membar);
3168 return membar;
3169 }
3170
3171 //-------------------------insert_mem_bar_volatile----------------------------
3172 // Memory barrier to avoid floating things around
3173 // The membar serves as a pinch point between both control and memory(alias_idx).
3174 // If you want to make a pinch point on all memory slices, do not use this
3175 // function (even with AliasIdxBot); use insert_mem_bar() instead.
3176 Node* GraphKit::insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent) {
3177 // When Parse::do_put_xxx updates a volatile field, it appends a series
3178 // of MemBarVolatile nodes, one for *each* volatile field alias category.
3179 // The first membar is on the same memory slice as the field store opcode.
3180 // This forces the membar to follow the store. (Bug 6500685 broke this.)
3181 // All the other membars (for other volatile slices, including AliasIdxBot,
3182 // which stands for all unknown volatile slices) are control-dependent
3183 // on the first membar. This prevents later volatile loads or stores
3184 // from sliding up past the just-emitted store.
3185
3186 MemBarNode* mb = MemBarNode::make(C, opcode, alias_idx, precedent);
3187 mb->set_req(TypeFunc::Control,control());
3188 if (alias_idx == Compile::AliasIdxBot) {
3189 mb->set_req(TypeFunc::Memory, merged_memory()->base_memory());
3190 } else {
3191 assert(!(opcode == Op_Initialize && alias_idx != Compile::AliasIdxRaw), "fix caller");
3192 mb->set_req(TypeFunc::Memory, memory(alias_idx));
3193 }
3194 Node* membar = _gvn.transform(mb);
3195 set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control)));
3196 if (alias_idx == Compile::AliasIdxBot) {
3197 merged_memory()->set_base_memory(_gvn.transform(new ProjNode(membar, TypeFunc::Memory)));
3198 } else {
3199 set_memory(_gvn.transform(new ProjNode(membar, TypeFunc::Memory)),alias_idx);
3200 }
3201 return membar;
3202 }
3203
3204 //------------------------------shared_lock------------------------------------
3205 // Emit locking code.
3206 FastLockNode* GraphKit::shared_lock(Node* obj) {
3207 // bci is either a monitorenter bc or InvocationEntryBci
3208 // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3209 assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3210
3211 if( !GenerateSynchronizationCode )
3212 return NULL; // Not locking things?
3213 if (stopped()) // Dead monitor?
3214 return NULL;
3215
3216 assert(dead_locals_are_killed(), "should kill locals before sync. point");
3217
3218 // Box the stack location
3219 Node* box = _gvn.transform(new BoxLockNode(next_monitor()));
3220 Node* mem = reset_memory();
3221
3222 FastLockNode * flock = _gvn.transform(new FastLockNode(0, obj, box) )->as_FastLock();
3223 if (UseBiasedLocking && PrintPreciseBiasedLockingStatistics) {
3224 // Create the counters for this fast lock.
3225 flock->create_lock_counter(sync_jvms()); // sync_jvms used to get current bci
3226 }
3227
3228 // Create the rtm counters for this fast lock if needed.
3229 flock->create_rtm_lock_counter(sync_jvms()); // sync_jvms used to get current bci
3230
3231 // Add monitor to debug info for the slow path. If we block inside the
3232 // slow path and de-opt, we need the monitor hanging around
3233 map()->push_monitor( flock );
3234
3235 const TypeFunc *tf = LockNode::lock_type();
3236 LockNode *lock = new LockNode(C, tf);
3237
3238 lock->init_req( TypeFunc::Control, control() );
3239 lock->init_req( TypeFunc::Memory , mem );
3240 lock->init_req( TypeFunc::I_O , top() ) ; // does no i/o
3241 lock->init_req( TypeFunc::FramePtr, frameptr() );
3242 lock->init_req( TypeFunc::ReturnAdr, top() );
3243
3244 lock->init_req(TypeFunc::Parms + 0, obj);
3245 lock->init_req(TypeFunc::Parms + 1, box);
3246 lock->init_req(TypeFunc::Parms + 2, flock);
3247 add_safepoint_edges(lock);
3248
3249 lock = _gvn.transform( lock )->as_Lock();
3250
3251 // lock has no side-effects, sets few values
3252 set_predefined_output_for_runtime_call(lock, mem, TypeRawPtr::BOTTOM);
3253
3254 insert_mem_bar(Op_MemBarAcquireLock);
3255
3256 // Add this to the worklist so that the lock can be eliminated
3257 record_for_igvn(lock);
3258
3259 #ifndef PRODUCT
3260 if (PrintLockStatistics) {
3261 // Update the counter for this lock. Don't bother using an atomic
3262 // operation since we don't require absolute accuracy.
3263 lock->create_lock_counter(map()->jvms());
3264 increment_counter(lock->counter()->addr());
3265 }
3266 #endif
3267
3268 return flock;
3269 }
3270
3271
3272 //------------------------------shared_unlock----------------------------------
3273 // Emit unlocking code.
3274 void GraphKit::shared_unlock(Node* box, Node* obj) {
3275 // bci is either a monitorenter bc or InvocationEntryBci
3276 // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3277 assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3278
3279 if( !GenerateSynchronizationCode )
3280 return;
3281 if (stopped()) { // Dead monitor?
3282 map()->pop_monitor(); // Kill monitor from debug info
3283 return;
3284 }
3285
3286 // Memory barrier to avoid floating things down past the locked region
3287 insert_mem_bar(Op_MemBarReleaseLock);
3288
3289 const TypeFunc *tf = OptoRuntime::complete_monitor_exit_Type();
3290 UnlockNode *unlock = new UnlockNode(C, tf);
3291 #ifdef ASSERT
3292 unlock->set_dbg_jvms(sync_jvms());
3293 #endif
3294 uint raw_idx = Compile::AliasIdxRaw;
3295 unlock->init_req( TypeFunc::Control, control() );
3296 unlock->init_req( TypeFunc::Memory , memory(raw_idx) );
3297 unlock->init_req( TypeFunc::I_O , top() ) ; // does no i/o
3298 unlock->init_req( TypeFunc::FramePtr, frameptr() );
3299 unlock->init_req( TypeFunc::ReturnAdr, top() );
3300
3301 unlock->init_req(TypeFunc::Parms + 0, obj);
3302 unlock->init_req(TypeFunc::Parms + 1, box);
3303 unlock = _gvn.transform(unlock)->as_Unlock();
3304
3305 Node* mem = reset_memory();
3306
3307 // unlock has no side-effects, sets few values
3308 set_predefined_output_for_runtime_call(unlock, mem, TypeRawPtr::BOTTOM);
3309
3310 // Kill monitor from debug info
3311 map()->pop_monitor( );
3312 }
3313
3314 //-------------------------------get_layout_helper-----------------------------
3315 // If the given klass is a constant or known to be an array,
3316 // fetch the constant layout helper value into constant_value
3317 // and return (Node*)NULL. Otherwise, load the non-constant
3318 // layout helper value, and return the node which represents it.
3319 // This two-faced routine is useful because allocation sites
3320 // almost always feature constant types.
3321 Node* GraphKit::get_layout_helper(Node* klass_node, jint& constant_value) {
3322 const TypeKlassPtr* inst_klass = _gvn.type(klass_node)->isa_klassptr();
3323 if (!StressReflectiveCode && inst_klass != NULL) {
3324 ciKlass* klass = inst_klass->klass();
3325 bool xklass = inst_klass->klass_is_exact();
3326 if (xklass || klass->is_array_klass()) {
3327 jint lhelper = klass->layout_helper();
3328 if (lhelper != Klass::_lh_neutral_value) {
3329 constant_value = lhelper;
3330 return (Node*) NULL;
3331 }
3332 }
3333 }
3334 constant_value = Klass::_lh_neutral_value; // put in a known value
3335 Node* lhp = basic_plus_adr(klass_node, klass_node, in_bytes(Klass::layout_helper_offset()));
3336 return make_load(NULL, lhp, TypeInt::INT, T_INT, MemNode::unordered);
3337 }
3338
3339 // We just put in an allocate/initialize with a big raw-memory effect.
3340 // Hook selected additional alias categories on the initialization.
3341 static void hook_memory_on_init(GraphKit& kit, int alias_idx,
3342 MergeMemNode* init_in_merge,
3343 Node* init_out_raw) {
3344 DEBUG_ONLY(Node* init_in_raw = init_in_merge->base_memory());
3345 assert(init_in_merge->memory_at(alias_idx) == init_in_raw, "");
3346
3347 Node* prevmem = kit.memory(alias_idx);
3348 init_in_merge->set_memory_at(alias_idx, prevmem);
3349 kit.set_memory(init_out_raw, alias_idx);
3350 }
3351
3352 //---------------------------set_output_for_allocation-------------------------
3353 Node* GraphKit::set_output_for_allocation(AllocateNode* alloc,
3354 const TypeOopPtr* oop_type,
3355 bool deoptimize_on_exception) {
3356 int rawidx = Compile::AliasIdxRaw;
3357 alloc->set_req( TypeFunc::FramePtr, frameptr() );
3358 add_safepoint_edges(alloc);
3359 Node* allocx = _gvn.transform(alloc);
3360 set_control( _gvn.transform(new ProjNode(allocx, TypeFunc::Control) ) );
3361 // create memory projection for i_o
3362 set_memory ( _gvn.transform( new ProjNode(allocx, TypeFunc::Memory, true) ), rawidx );
3363 make_slow_call_ex(allocx, env()->Throwable_klass(), true, deoptimize_on_exception);
3364
3365 // create a memory projection as for the normal control path
3366 Node* malloc = _gvn.transform(new ProjNode(allocx, TypeFunc::Memory));
3367 set_memory(malloc, rawidx);
3368
3369 // a normal slow-call doesn't change i_o, but an allocation does
3370 // we create a separate i_o projection for the normal control path
3371 set_i_o(_gvn.transform( new ProjNode(allocx, TypeFunc::I_O, false) ) );
3372 Node* rawoop = _gvn.transform( new ProjNode(allocx, TypeFunc::Parms) );
3373
3374 // put in an initialization barrier
3375 InitializeNode* init = insert_mem_bar_volatile(Op_Initialize, rawidx,
3376 rawoop)->as_Initialize();
3377 assert(alloc->initialization() == init, "2-way macro link must work");
3378 assert(init ->allocation() == alloc, "2-way macro link must work");
3379 {
3380 // Extract memory strands which may participate in the new object's
3381 // initialization, and source them from the new InitializeNode.
3382 // This will allow us to observe initializations when they occur,
3383 // and link them properly (as a group) to the InitializeNode.
3384 assert(init->in(InitializeNode::Memory) == malloc, "");
3385 MergeMemNode* minit_in = MergeMemNode::make(malloc);
3386 init->set_req(InitializeNode::Memory, minit_in);
3387 record_for_igvn(minit_in); // fold it up later, if possible
3388 Node* minit_out = memory(rawidx);
3389 assert(minit_out->is_Proj() && minit_out->in(0) == init, "");
3390 if (oop_type->isa_aryptr()) {
3391 const TypePtr* telemref = oop_type->add_offset(Type::OffsetBot);
3392 int elemidx = C->get_alias_index(telemref);
3393 hook_memory_on_init(*this, elemidx, minit_in, minit_out);
3394 } else if (oop_type->isa_instptr()) {
3395 ciInstanceKlass* ik = oop_type->klass()->as_instance_klass();
3396 for (int i = 0, len = ik->nof_nonstatic_fields(); i < len; i++) {
3397 ciField* field = ik->nonstatic_field_at(i);
3398 if (field->offset() >= TrackedInitializationLimit * HeapWordSize)
3399 continue; // do not bother to track really large numbers of fields
3400 // Find (or create) the alias category for this field:
3401 int fieldidx = C->alias_type(field)->index();
3402 hook_memory_on_init(*this, fieldidx, minit_in, minit_out);
3403 }
3404 }
3405 }
3406
3407 // Cast raw oop to the real thing...
3408 Node* javaoop = new CheckCastPPNode(control(), rawoop, oop_type);
3409 javaoop = _gvn.transform(javaoop);
3410 C->set_recent_alloc(control(), javaoop);
3411 assert(just_allocated_object(control()) == javaoop, "just allocated");
3412
3413 #ifdef ASSERT
3414 { // Verify that the AllocateNode::Ideal_allocation recognizers work:
3415 assert(AllocateNode::Ideal_allocation(rawoop, &_gvn) == alloc,
3416 "Ideal_allocation works");
3417 assert(AllocateNode::Ideal_allocation(javaoop, &_gvn) == alloc,
3418 "Ideal_allocation works");
3419 if (alloc->is_AllocateArray()) {
3420 assert(AllocateArrayNode::Ideal_array_allocation(rawoop, &_gvn) == alloc->as_AllocateArray(),
3421 "Ideal_allocation works");
3422 assert(AllocateArrayNode::Ideal_array_allocation(javaoop, &_gvn) == alloc->as_AllocateArray(),
3423 "Ideal_allocation works");
3424 } else {
3425 assert(alloc->in(AllocateNode::ALength)->is_top(), "no length, please");
3426 }
3427 }
3428 #endif //ASSERT
3429
3430 return javaoop;
3431 }
3432
3433 //---------------------------new_instance--------------------------------------
3434 // This routine takes a klass_node which may be constant (for a static type)
3435 // or may be non-constant (for reflective code). It will work equally well
3436 // for either, and the graph will fold nicely if the optimizer later reduces
3437 // the type to a constant.
3438 // The optional arguments are for specialized use by intrinsics:
3439 // - If 'extra_slow_test' if not null is an extra condition for the slow-path.
3440 // - If 'return_size_val', report the the total object size to the caller.
3441 // - deoptimize_on_exception controls how Java exceptions are handled (rethrow vs deoptimize)
3442 Node* GraphKit::new_instance(Node* klass_node,
3443 Node* extra_slow_test,
3444 Node* *return_size_val,
3445 bool deoptimize_on_exception) {
3446 // Compute size in doublewords
3447 // The size is always an integral number of doublewords, represented
3448 // as a positive bytewise size stored in the klass's layout_helper.
3449 // The layout_helper also encodes (in a low bit) the need for a slow path.
3450 jint layout_con = Klass::_lh_neutral_value;
3451 Node* layout_val = get_layout_helper(klass_node, layout_con);
3452 int layout_is_con = (layout_val == NULL);
3453
3454 if (extra_slow_test == NULL) extra_slow_test = intcon(0);
3455 // Generate the initial go-slow test. It's either ALWAYS (return a
3456 // Node for 1) or NEVER (return a NULL) or perhaps (in the reflective
3457 // case) a computed value derived from the layout_helper.
3458 Node* initial_slow_test = NULL;
3459 if (layout_is_con) {
3460 assert(!StressReflectiveCode, "stress mode does not use these paths");
3461 bool must_go_slow = Klass::layout_helper_needs_slow_path(layout_con);
3462 initial_slow_test = must_go_slow ? intcon(1) : extra_slow_test;
3463 } else { // reflective case
3464 // This reflective path is used by Unsafe.allocateInstance.
3465 // (It may be stress-tested by specifying StressReflectiveCode.)
3466 // Basically, we want to get into the VM is there's an illegal argument.
3467 Node* bit = intcon(Klass::_lh_instance_slow_path_bit);
3468 initial_slow_test = _gvn.transform( new AndINode(layout_val, bit) );
3469 if (extra_slow_test != intcon(0)) {
3470 initial_slow_test = _gvn.transform( new OrINode(initial_slow_test, extra_slow_test) );
3471 }
3472 // (Macro-expander will further convert this to a Bool, if necessary.)
3473 }
3474
3475 // Find the size in bytes. This is easy; it's the layout_helper.
3476 // The size value must be valid even if the slow path is taken.
3477 Node* size = NULL;
3478 if (layout_is_con) {
3479 size = MakeConX(Klass::layout_helper_size_in_bytes(layout_con));
3480 } else { // reflective case
3481 // This reflective path is used by clone and Unsafe.allocateInstance.
3482 size = ConvI2X(layout_val);
3483
3484 // Clear the low bits to extract layout_helper_size_in_bytes:
3485 assert((int)Klass::_lh_instance_slow_path_bit < BytesPerLong, "clear bit");
3486 Node* mask = MakeConX(~ (intptr_t)right_n_bits(LogBytesPerLong));
3487 size = _gvn.transform( new AndXNode(size, mask) );
3488 }
3489 if (return_size_val != NULL) {
3490 (*return_size_val) = size;
3491 }
3492
3493 // This is a precise notnull oop of the klass.
3494 // (Actually, it need not be precise if this is a reflective allocation.)
3495 // It's what we cast the result to.
3496 const TypeKlassPtr* tklass = _gvn.type(klass_node)->isa_klassptr();
3497 if (!tklass) tklass = TypeKlassPtr::OBJECT;
3498 const TypeOopPtr* oop_type = tklass->as_instance_type();
3499
3500 // Now generate allocation code
3501
3502 // The entire memory state is needed for slow path of the allocation
3503 // since GC and deoptimization can happened.
3504 Node *mem = reset_memory();
3505 set_all_memory(mem); // Create new memory state
3506
3507 AllocateNode* alloc = new AllocateNode(C, AllocateNode::alloc_type(Type::TOP),
3508 control(), mem, i_o(),
3509 size, klass_node,
3510 initial_slow_test);
3511
3512 return set_output_for_allocation(alloc, oop_type, deoptimize_on_exception);
3513 }
3514
3515 //-------------------------------new_array-------------------------------------
3516 // helper for both newarray and anewarray
3517 // The 'length' parameter is (obviously) the length of the array.
3518 // See comments on new_instance for the meaning of the other arguments.
3519 Node* GraphKit::new_array(Node* klass_node, // array klass (maybe variable)
3520 Node* length, // number of array elements
3521 int nargs, // number of arguments to push back for uncommon trap
3522 Node* *return_size_val,
3523 bool deoptimize_on_exception) {
3524 jint layout_con = Klass::_lh_neutral_value;
3525 Node* layout_val = get_layout_helper(klass_node, layout_con);
3526 int layout_is_con = (layout_val == NULL);
3527
3528 if (!layout_is_con && !StressReflectiveCode &&
3529 !too_many_traps(Deoptimization::Reason_class_check)) {
3530 // This is a reflective array creation site.
3531 // Optimistically assume that it is a subtype of Object[],
3532 // so that we can fold up all the address arithmetic.
3533 layout_con = Klass::array_layout_helper(T_OBJECT);
3534 Node* cmp_lh = _gvn.transform( new CmpINode(layout_val, intcon(layout_con)) );
3535 Node* bol_lh = _gvn.transform( new BoolNode(cmp_lh, BoolTest::eq) );
3536 { BuildCutout unless(this, bol_lh, PROB_MAX);
3537 inc_sp(nargs);
3538 uncommon_trap(Deoptimization::Reason_class_check,
3539 Deoptimization::Action_maybe_recompile);
3540 }
3541 layout_val = NULL;
3542 layout_is_con = true;
3543 }
3544
3545 // Generate the initial go-slow test. Make sure we do not overflow
3546 // if length is huge (near 2Gig) or negative! We do not need
3547 // exact double-words here, just a close approximation of needed
3548 // double-words. We can't add any offset or rounding bits, lest we
3549 // take a size -1 of bytes and make it positive. Use an unsigned
3550 // compare, so negative sizes look hugely positive.
3551 int fast_size_limit = FastAllocateSizeLimit;
3552 if (layout_is_con) {
3553 assert(!StressReflectiveCode, "stress mode does not use these paths");
3554 // Increase the size limit if we have exact knowledge of array type.
3555 int log2_esize = Klass::layout_helper_log2_element_size(layout_con);
3556 fast_size_limit <<= (LogBytesPerLong - log2_esize);
3557 }
3558
3559 Node* initial_slow_cmp = _gvn.transform( new CmpUNode( length, intcon( fast_size_limit ) ) );
3560 Node* initial_slow_test = _gvn.transform( new BoolNode( initial_slow_cmp, BoolTest::gt ) );
3561
3562 // --- Size Computation ---
3563 // array_size = round_to_heap(array_header + (length << elem_shift));
3564 // where round_to_heap(x) == align_to(x, MinObjAlignmentInBytes)
3565 // and align_to(x, y) == ((x + y-1) & ~(y-1))
3566 // The rounding mask is strength-reduced, if possible.
3567 int round_mask = MinObjAlignmentInBytes - 1;
3568 Node* header_size = NULL;
3569 int header_size_min = arrayOopDesc::base_offset_in_bytes(T_BYTE);
3570 // (T_BYTE has the weakest alignment and size restrictions...)
3571 if (layout_is_con) {
3572 int hsize = Klass::layout_helper_header_size(layout_con);
3573 int eshift = Klass::layout_helper_log2_element_size(layout_con);
3574 BasicType etype = Klass::layout_helper_element_type(layout_con);
3575 if ((round_mask & ~right_n_bits(eshift)) == 0)
3576 round_mask = 0; // strength-reduce it if it goes away completely
3577 assert((hsize & right_n_bits(eshift)) == 0, "hsize is pre-rounded");
3578 assert(header_size_min <= hsize, "generic minimum is smallest");
3579 header_size_min = hsize;
3580 header_size = intcon(hsize + round_mask);
3581 } else {
3582 Node* hss = intcon(Klass::_lh_header_size_shift);
3583 Node* hsm = intcon(Klass::_lh_header_size_mask);
3584 Node* hsize = _gvn.transform( new URShiftINode(layout_val, hss) );
3585 hsize = _gvn.transform( new AndINode(hsize, hsm) );
3586 Node* mask = intcon(round_mask);
3587 header_size = _gvn.transform( new AddINode(hsize, mask) );
3588 }
3589
3590 Node* elem_shift = NULL;
3591 if (layout_is_con) {
3592 int eshift = Klass::layout_helper_log2_element_size(layout_con);
3593 if (eshift != 0)
3594 elem_shift = intcon(eshift);
3595 } else {
3596 // There is no need to mask or shift this value.
3597 // The semantics of LShiftINode include an implicit mask to 0x1F.
3598 assert(Klass::_lh_log2_element_size_shift == 0, "use shift in place");
3599 elem_shift = layout_val;
3600 }
3601
3602 // Transition to native address size for all offset calculations:
3603 Node* lengthx = ConvI2X(length);
3604 Node* headerx = ConvI2X(header_size);
3605 #ifdef _LP64
3606 { const TypeInt* tilen = _gvn.find_int_type(length);
3607 if (tilen != NULL && tilen->_lo < 0) {
3608 // Add a manual constraint to a positive range. Cf. array_element_address.
3609 jint size_max = fast_size_limit;
3610 if (size_max > tilen->_hi) size_max = tilen->_hi;
3611 const TypeInt* tlcon = TypeInt::make(0, size_max, Type::WidenMin);
3612
3613 // Only do a narrow I2L conversion if the range check passed.
3614 IfNode* iff = new IfNode(control(), initial_slow_test, PROB_MIN, COUNT_UNKNOWN);
3615 _gvn.transform(iff);
3616 RegionNode* region = new RegionNode(3);
3617 _gvn.set_type(region, Type::CONTROL);
3618 lengthx = new PhiNode(region, TypeLong::LONG);
3619 _gvn.set_type(lengthx, TypeLong::LONG);
3620
3621 // Range check passed. Use ConvI2L node with narrow type.
3622 Node* passed = IfFalse(iff);
3623 region->init_req(1, passed);
3624 // Make I2L conversion control dependent to prevent it from
3625 // floating above the range check during loop optimizations.
3626 lengthx->init_req(1, C->constrained_convI2L(&_gvn, length, tlcon, passed));
3627
3628 // Range check failed. Use ConvI2L with wide type because length may be invalid.
3629 region->init_req(2, IfTrue(iff));
3630 lengthx->init_req(2, ConvI2X(length));
3631
3632 set_control(region);
3633 record_for_igvn(region);
3634 record_for_igvn(lengthx);
3635 }
3636 }
3637 #endif
3638
3639 // Combine header size (plus rounding) and body size. Then round down.
3640 // This computation cannot overflow, because it is used only in two
3641 // places, one where the length is sharply limited, and the other
3642 // after a successful allocation.
3643 Node* abody = lengthx;
3644 if (elem_shift != NULL)
3645 abody = _gvn.transform( new LShiftXNode(lengthx, elem_shift) );
3646 Node* size = _gvn.transform( new AddXNode(headerx, abody) );
3647 if (round_mask != 0) {
3648 Node* mask = MakeConX(~round_mask);
3649 size = _gvn.transform( new AndXNode(size, mask) );
3650 }
3651 // else if round_mask == 0, the size computation is self-rounding
3652
3653 if (return_size_val != NULL) {
3654 // This is the size
3655 (*return_size_val) = size;
3656 }
3657
3658 // Now generate allocation code
3659
3660 // The entire memory state is needed for slow path of the allocation
3661 // since GC and deoptimization can happened.
3662 Node *mem = reset_memory();
3663 set_all_memory(mem); // Create new memory state
3664
3665 if (initial_slow_test->is_Bool()) {
3666 // Hide it behind a CMoveI, or else PhaseIdealLoop::split_up will get sick.
3667 initial_slow_test = initial_slow_test->as_Bool()->as_int_value(&_gvn);
3668 }
3669
3670 // Create the AllocateArrayNode and its result projections
3671 AllocateArrayNode* alloc
3672 = new AllocateArrayNode(C, AllocateArrayNode::alloc_type(TypeInt::INT),
3673 control(), mem, i_o(),
3674 size, klass_node,
3675 initial_slow_test,
3676 length);
3677
3678 // Cast to correct type. Note that the klass_node may be constant or not,
3679 // and in the latter case the actual array type will be inexact also.
3680 // (This happens via a non-constant argument to inline_native_newArray.)
3681 // In any case, the value of klass_node provides the desired array type.
3682 const TypeInt* length_type = _gvn.find_int_type(length);
3683 const TypeOopPtr* ary_type = _gvn.type(klass_node)->is_klassptr()->as_instance_type();
3684 if (ary_type->isa_aryptr() && length_type != NULL) {
3685 // Try to get a better type than POS for the size
3686 ary_type = ary_type->is_aryptr()->cast_to_size(length_type);
3687 }
3688
3689 Node* javaoop = set_output_for_allocation(alloc, ary_type, deoptimize_on_exception);
3690
3691 // Cast length on remaining path to be as narrow as possible
3692 if (map()->find_edge(length) >= 0) {
3693 Node* ccast = alloc->make_ideal_length(ary_type, &_gvn);
3694 if (ccast != length) {
3695 _gvn.set_type_bottom(ccast);
3696 record_for_igvn(ccast);
3697 replace_in_map(length, ccast);
3698 }
3699 }
3700
3701 return javaoop;
3702 }
3703
3704 // The following "Ideal_foo" functions are placed here because they recognize
3705 // the graph shapes created by the functions immediately above.
3706
3707 //---------------------------Ideal_allocation----------------------------------
3708 // Given an oop pointer or raw pointer, see if it feeds from an AllocateNode.
3709 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase) {
3710 if (ptr == NULL) { // reduce dumb test in callers
3711 return NULL;
3712 }
3713 if (ptr->is_CheckCastPP()) { // strip only one raw-to-oop cast
3714 ptr = ptr->in(1);
3715 if (ptr == NULL) return NULL;
3716 }
3717 // Return NULL for allocations with several casts:
3718 // j.l.reflect.Array.newInstance(jobject, jint)
3719 // Object.clone()
3720 // to keep more precise type from last cast.
3721 if (ptr->is_Proj()) {
3722 Node* allo = ptr->in(0);
3723 if (allo != NULL && allo->is_Allocate()) {
3724 return allo->as_Allocate();
3725 }
3726 }
3727 // Report failure to match.
3728 return NULL;
3729 }
3730
3731 // Fancy version which also strips off an offset (and reports it to caller).
3732 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase,
3733 intptr_t& offset) {
3734 Node* base = AddPNode::Ideal_base_and_offset(ptr, phase, offset);
3735 if (base == NULL) return NULL;
3736 return Ideal_allocation(base, phase);
3737 }
3738
3739 // Trace Initialize <- Proj[Parm] <- Allocate
3740 AllocateNode* InitializeNode::allocation() {
3741 Node* rawoop = in(InitializeNode::RawAddress);
3742 if (rawoop->is_Proj()) {
3743 Node* alloc = rawoop->in(0);
3744 if (alloc->is_Allocate()) {
3745 return alloc->as_Allocate();
3746 }
3747 }
3748 return NULL;
3749 }
3750
3751 // Trace Allocate -> Proj[Parm] -> Initialize
3752 InitializeNode* AllocateNode::initialization() {
3753 ProjNode* rawoop = proj_out_or_null(AllocateNode::RawAddress);
3754 if (rawoop == NULL) return NULL;
3755 for (DUIterator_Fast imax, i = rawoop->fast_outs(imax); i < imax; i++) {
3756 Node* init = rawoop->fast_out(i);
3757 if (init->is_Initialize()) {
3758 assert(init->as_Initialize()->allocation() == this, "2-way link");
3759 return init->as_Initialize();
3760 }
3761 }
3762 return NULL;
3763 }
3764
3765 //----------------------------- loop predicates ---------------------------
3766
3767 //------------------------------add_predicate_impl----------------------------
3768 void GraphKit::add_predicate_impl(Deoptimization::DeoptReason reason, int nargs) {
3769 // Too many traps seen?
3770 if (too_many_traps(reason)) {
3771 #ifdef ASSERT
3772 if (TraceLoopPredicate) {
3773 int tc = C->trap_count(reason);
3774 tty->print("too many traps=%s tcount=%d in ",
3775 Deoptimization::trap_reason_name(reason), tc);
3776 method()->print(); // which method has too many predicate traps
3777 tty->cr();
3778 }
3779 #endif
3780 // We cannot afford to take more traps here,
3781 // do not generate predicate.
3782 return;
3783 }
3784
3785 Node *cont = _gvn.intcon(1);
3786 Node* opq = _gvn.transform(new Opaque1Node(C, cont));
3787 Node *bol = _gvn.transform(new Conv2BNode(opq));
3788 IfNode* iff = create_and_map_if(control(), bol, PROB_MAX, COUNT_UNKNOWN);
3789 Node* iffalse = _gvn.transform(new IfFalseNode(iff));
3790 C->add_predicate_opaq(opq);
3791 {
3792 PreserveJVMState pjvms(this);
3793 set_control(iffalse);
3794 inc_sp(nargs);
3795 uncommon_trap(reason, Deoptimization::Action_maybe_recompile);
3796 }
3797 Node* iftrue = _gvn.transform(new IfTrueNode(iff));
3798 set_control(iftrue);
3799 }
3800
3801 //------------------------------add_predicate---------------------------------
3802 void GraphKit::add_predicate(int nargs) {
3803 if (UseLoopPredicate) {
3804 add_predicate_impl(Deoptimization::Reason_predicate, nargs);
3805 }
3806 // loop's limit check predicate should be near the loop.
3807 add_predicate_impl(Deoptimization::Reason_loop_limit_check, nargs);
3808 }
3809
3810 //----------------------------- store barriers ----------------------------
3811 #define __ ideal.
3812
3813 bool GraphKit::use_ReduceInitialCardMarks() {
3814 BarrierSet *bs = Universe::heap()->barrier_set();
3815 return bs->is_a(BarrierSet::CardTableBarrierSet)
3816 && barrier_set_cast<CardTableBarrierSet>(bs)->can_elide_tlab_store_barriers()
3817 && ReduceInitialCardMarks;
3818 }
3819
3820 void GraphKit::sync_kit(IdealKit& ideal) {
3821 set_all_memory(__ merged_memory());
3822 set_i_o(__ i_o());
3823 set_control(__ ctrl());
3824 }
3825
3826 void GraphKit::final_sync(IdealKit& ideal) {
3827 // Final sync IdealKit and graphKit.
3828 sync_kit(ideal);
3829 }
3830
3831 Node* GraphKit::byte_map_base_node() {
3832 // Get base of card map
3833 jbyte* card_table_base = ci_card_table_address();
3834 if (card_table_base != NULL) {
3835 return makecon(TypeRawPtr::make((address)card_table_base));
3836 } else {
3837 return null();
3838 }
3839 }
3840
3841 // vanilla/CMS post barrier
3842 // Insert a write-barrier store. This is to let generational GC work; we have
3843 // to flag all oop-stores before the next GC point.
3844 void GraphKit::write_barrier_post(Node* oop_store,
3845 Node* obj,
3846 Node* adr,
3847 uint adr_idx,
3848 Node* val,
3849 bool use_precise) {
3850 // No store check needed if we're storing a NULL or an old object
3851 // (latter case is probably a string constant). The concurrent
3852 // mark sweep garbage collector, however, needs to have all nonNull
3853 // oop updates flagged via card-marks.
3854 if (val != NULL && val->is_Con()) {
3855 // must be either an oop or NULL
3856 const Type* t = val->bottom_type();
3857 if (t == TypePtr::NULL_PTR || t == Type::TOP)
3858 // stores of null never (?) need barriers
3859 return;
3860 }
3861
3862 if (use_ReduceInitialCardMarks()
3863 && obj == just_allocated_object(control())) {
3864 // We can skip marks on a freshly-allocated object in Eden.
3865 // Keep this code in sync with new_deferred_store_barrier() in runtime.cpp.
3866 // That routine informs GC to take appropriate compensating steps,
3867 // upon a slow-path allocation, so as to make this card-mark
3868 // elision safe.
3869 return;
3870 }
3871
3872 if (!use_precise) {
3873 // All card marks for a (non-array) instance are in one place:
3874 adr = obj;
3875 }
3876 // (Else it's an array (or unknown), and we want more precise card marks.)
3877 assert(adr != NULL, "");
3878
3879 IdealKit ideal(this, true);
3880
3881 // Convert the pointer to an int prior to doing math on it
3882 Node* cast = __ CastPX(__ ctrl(), adr);
3883
3884 // Divide by card size
3885 assert(Universe::heap()->barrier_set()->is_a(BarrierSet::CardTableBarrierSet),
3886 "Only one we handle so far.");
3887 Node* card_offset = __ URShiftX( cast, __ ConI(CardTable::card_shift) );
3888
3889 // Combine card table base and card offset
3890 Node* card_adr = __ AddP(__ top(), byte_map_base_node(), card_offset );
3891
3892 // Get the alias_index for raw card-mark memory
3893 int adr_type = Compile::AliasIdxRaw;
3894 Node* zero = __ ConI(0); // Dirty card value
3895 BasicType bt = T_BYTE;
3896
3897 if (UseConcMarkSweepGC && UseCondCardMark) {
3898 insert_mem_bar(Op_MemBarVolatile); // StoreLoad barrier
3899 __ sync_kit(this);
3900 }
3901
3902 if (UseCondCardMark) {
3903 // The classic GC reference write barrier is typically implemented
3904 // as a store into the global card mark table. Unfortunately
3905 // unconditional stores can result in false sharing and excessive
3906 // coherence traffic as well as false transactional aborts.
3907 // UseCondCardMark enables MP "polite" conditional card mark
3908 // stores. In theory we could relax the load from ctrl() to
3909 // no_ctrl, but that doesn't buy much latitude.
3910 Node* card_val = __ load( __ ctrl(), card_adr, TypeInt::BYTE, bt, adr_type);
3911 __ if_then(card_val, BoolTest::ne, zero);
3912 }
3913
3914 // Smash zero into card
3915 if( !UseConcMarkSweepGC ) {
3916 __ store(__ ctrl(), card_adr, zero, bt, adr_type, MemNode::unordered);
3917 } else {
3918 // Specialized path for CM store barrier
3919 __ storeCM(__ ctrl(), card_adr, zero, oop_store, adr_idx, bt, adr_type);
3920 }
3921
3922 if (UseCondCardMark) {
3923 __ end_if();
3924 }
3925
3926 // Final sync IdealKit and GraphKit.
3927 final_sync(ideal);
3928 }
3929 /*
3930 * Determine if the G1 pre-barrier can be removed. The pre-barrier is
3931 * required by SATB to make sure all objects live at the start of the
3932 * marking are kept alive, all reference updates need to any previous
3933 * reference stored before writing.
3934 *
3935 * If the previous value is NULL there is no need to save the old value.
3936 * References that are NULL are filtered during runtime by the barrier
3937 * code to avoid unnecessary queuing.
3938 *
3939 * However in the case of newly allocated objects it might be possible to
3940 * prove that the reference about to be overwritten is NULL during compile
3941 * time and avoid adding the barrier code completely.
3942 *
3943 * The compiler needs to determine that the object in which a field is about
3944 * to be written is newly allocated, and that no prior store to the same field
3945 * has happened since the allocation.
3946 *
3947 * Returns true if the pre-barrier can be removed
3948 */
3949 bool GraphKit::g1_can_remove_pre_barrier(PhaseTransform* phase, Node* adr,
3950 BasicType bt, uint adr_idx) {
3951 intptr_t offset = 0;
3952 Node* base = AddPNode::Ideal_base_and_offset(adr, phase, offset);
3953 AllocateNode* alloc = AllocateNode::Ideal_allocation(base, phase);
3954
3955 if (offset == Type::OffsetBot) {
3956 return false; // cannot unalias unless there are precise offsets
3957 }
3958
3959 if (alloc == NULL) {
3960 return false; // No allocation found
3961 }
3962
3963 intptr_t size_in_bytes = type2aelembytes(bt);
3964
3965 Node* mem = memory(adr_idx); // start searching here...
3966
3967 for (int cnt = 0; cnt < 50; cnt++) {
3968
3969 if (mem->is_Store()) {
3970
3971 Node* st_adr = mem->in(MemNode::Address);
3972 intptr_t st_offset = 0;
3973 Node* st_base = AddPNode::Ideal_base_and_offset(st_adr, phase, st_offset);
3974
3975 if (st_base == NULL) {
3976 break; // inscrutable pointer
3977 }
3978
3979 // Break we have found a store with same base and offset as ours so break
3980 if (st_base == base && st_offset == offset) {
3981 break;
3982 }
3983
3984 if (st_offset != offset && st_offset != Type::OffsetBot) {
3985 const int MAX_STORE = BytesPerLong;
3986 if (st_offset >= offset + size_in_bytes ||
3987 st_offset <= offset - MAX_STORE ||
3988 st_offset <= offset - mem->as_Store()->memory_size()) {
3989 // Success: The offsets are provably independent.
3990 // (You may ask, why not just test st_offset != offset and be done?
3991 // The answer is that stores of different sizes can co-exist
3992 // in the same sequence of RawMem effects. We sometimes initialize
3993 // a whole 'tile' of array elements with a single jint or jlong.)
3994 mem = mem->in(MemNode::Memory);
3995 continue; // advance through independent store memory
3996 }
3997 }
3998
3999 if (st_base != base
4000 && MemNode::detect_ptr_independence(base, alloc, st_base,
4001 AllocateNode::Ideal_allocation(st_base, phase),
4002 phase)) {
4003 // Success: The bases are provably independent.
4004 mem = mem->in(MemNode::Memory);
4005 continue; // advance through independent store memory
4006 }
4007 } else if (mem->is_Proj() && mem->in(0)->is_Initialize()) {
4008
4009 InitializeNode* st_init = mem->in(0)->as_Initialize();
4010 AllocateNode* st_alloc = st_init->allocation();
4011
4012 // Make sure that we are looking at the same allocation site.
4013 // The alloc variable is guaranteed to not be null here from earlier check.
4014 if (alloc == st_alloc) {
4015 // Check that the initialization is storing NULL so that no previous store
4016 // has been moved up and directly write a reference
4017 Node* captured_store = st_init->find_captured_store(offset,
4018 type2aelembytes(T_OBJECT),
4019 phase);
4020 if (captured_store == NULL || captured_store == st_init->zero_memory()) {
4021 return true;
4022 }
4023 }
4024 }
4025
4026 // Unless there is an explicit 'continue', we must bail out here,
4027 // because 'mem' is an inscrutable memory state (e.g., a call).
4028 break;
4029 }
4030
4031 return false;
4032 }
4033
4034 // G1 pre/post barriers
4035 void GraphKit::g1_write_barrier_pre(bool do_load,
4036 Node* obj,
4037 Node* adr,
4038 uint alias_idx,
4039 Node* val,
4040 const TypeOopPtr* val_type,
4041 Node* pre_val,
4042 BasicType bt) {
4043
4044 // Some sanity checks
4045 // Note: val is unused in this routine.
4046
4047 if (do_load) {
4048 // We need to generate the load of the previous value
4049 assert(obj != NULL, "must have a base");
4050 assert(adr != NULL, "where are loading from?");
4051 assert(pre_val == NULL, "loaded already?");
4052 assert(val_type != NULL, "need a type");
4053
4054 if (use_ReduceInitialCardMarks()
4055 && g1_can_remove_pre_barrier(&_gvn, adr, bt, alias_idx)) {
4056 return;
4057 }
4058
4059 } else {
4060 // In this case both val_type and alias_idx are unused.
4061 assert(pre_val != NULL, "must be loaded already");
4062 // Nothing to be done if pre_val is null.
4063 if (pre_val->bottom_type() == TypePtr::NULL_PTR) return;
4064 assert(pre_val->bottom_type()->basic_type() == T_OBJECT, "or we shouldn't be here");
4065 }
4066 assert(bt == T_OBJECT, "or we shouldn't be here");
4067
4068 IdealKit ideal(this, true);
4069
4070 Node* tls = __ thread(); // ThreadLocalStorage
4071
4072 Node* no_ctrl = NULL;
4073 Node* no_base = __ top();
4074 Node* zero = __ ConI(0);
4075 Node* zeroX = __ ConX(0);
4076
4077 float likely = PROB_LIKELY(0.999);
4078 float unlikely = PROB_UNLIKELY(0.999);
4079
4080 BasicType active_type = in_bytes(SATBMarkQueue::byte_width_of_active()) == 4 ? T_INT : T_BYTE;
4081 assert(in_bytes(SATBMarkQueue::byte_width_of_active()) == 4 || in_bytes(SATBMarkQueue::byte_width_of_active()) == 1, "flag width");
4082
4083 // Offsets into the thread
4084 const int marking_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 648
4085 SATBMarkQueue::byte_offset_of_active());
4086 const int index_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 656
4087 SATBMarkQueue::byte_offset_of_index());
4088 const int buffer_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 652
4089 SATBMarkQueue::byte_offset_of_buf());
4090
4091 // Now the actual pointers into the thread
4092 Node* marking_adr = __ AddP(no_base, tls, __ ConX(marking_offset));
4093 Node* buffer_adr = __ AddP(no_base, tls, __ ConX(buffer_offset));
4094 Node* index_adr = __ AddP(no_base, tls, __ ConX(index_offset));
4095
4096 // Now some of the values
4097 Node* marking = __ load(__ ctrl(), marking_adr, TypeInt::INT, active_type, Compile::AliasIdxRaw);
4098
4099 // if (!marking)
4100 __ if_then(marking, BoolTest::ne, zero, unlikely); {
4101 BasicType index_bt = TypeX_X->basic_type();
4102 assert(sizeof(size_t) == type2aelembytes(index_bt), "Loading G1 SATBMarkQueue::_index with wrong size.");
4103 Node* index = __ load(__ ctrl(), index_adr, TypeX_X, index_bt, Compile::AliasIdxRaw);
4104
4105 if (do_load) {
4106 // load original value
4107 // alias_idx correct??
4108 pre_val = __ load(__ ctrl(), adr, val_type, bt, alias_idx);
4109 }
4110
4111 // if (pre_val != NULL)
4112 __ if_then(pre_val, BoolTest::ne, null()); {
4113 Node* buffer = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw);
4114
4115 // is the queue for this thread full?
4116 __ if_then(index, BoolTest::ne, zeroX, likely); {
4117
4118 // decrement the index
4119 Node* next_index = _gvn.transform(new SubXNode(index, __ ConX(sizeof(intptr_t))));
4120
4121 // Now get the buffer location we will log the previous value into and store it
4122 Node *log_addr = __ AddP(no_base, buffer, next_index);
4123 __ store(__ ctrl(), log_addr, pre_val, T_OBJECT, Compile::AliasIdxRaw, MemNode::unordered);
4124 // update the index
4125 __ store(__ ctrl(), index_adr, next_index, index_bt, Compile::AliasIdxRaw, MemNode::unordered);
4126
4127 } __ else_(); {
4128
4129 // logging buffer is full, call the runtime
4130 const TypeFunc *tf = OptoRuntime::g1_wb_pre_Type();
4131 __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_pre), "g1_wb_pre", pre_val, tls);
4132 } __ end_if(); // (!index)
4133 } __ end_if(); // (pre_val != NULL)
4134 } __ end_if(); // (!marking)
4135
4136 // Final sync IdealKit and GraphKit.
4137 final_sync(ideal);
4138 }
4139
4140 /*
4141 * G1 similar to any GC with a Young Generation requires a way to keep track of
4142 * references from Old Generation to Young Generation to make sure all live
4143 * objects are found. G1 also requires to keep track of object references
4144 * between different regions to enable evacuation of old regions, which is done
4145 * as part of mixed collections. References are tracked in remembered sets and
4146 * is continuously updated as reference are written to with the help of the
4147 * post-barrier.
4148 *
4149 * To reduce the number of updates to the remembered set the post-barrier
4150 * filters updates to fields in objects located in the Young Generation,
4151 * the same region as the reference, when the NULL is being written or
4152 * if the card is already marked as dirty by an earlier write.
4153 *
4154 * Under certain circumstances it is possible to avoid generating the
4155 * post-barrier completely if it is possible during compile time to prove
4156 * the object is newly allocated and that no safepoint exists between the
4157 * allocation and the store.
4158 *
4159 * In the case of slow allocation the allocation code must handle the barrier
4160 * as part of the allocation in the case the allocated object is not located
4161 * in the nursery, this would happen for humongous objects. This is similar to
4162 * how CMS is required to handle this case, see the comments for the method
4163 * CardTableBarrierSet::on_allocation_slowpath_exit and OptoRuntime::new_deferred_store_barrier.
4164 * A deferred card mark is required for these objects and handled in the above
4165 * mentioned methods.
4166 *
4167 * Returns true if the post barrier can be removed
4168 */
4169 bool GraphKit::g1_can_remove_post_barrier(PhaseTransform* phase, Node* store,
4170 Node* adr) {
4171 intptr_t offset = 0;
4172 Node* base = AddPNode::Ideal_base_and_offset(adr, phase, offset);
4173 AllocateNode* alloc = AllocateNode::Ideal_allocation(base, phase);
4174
4175 if (offset == Type::OffsetBot) {
4176 return false; // cannot unalias unless there are precise offsets
4177 }
4178
4179 if (alloc == NULL) {
4180 return false; // No allocation found
4181 }
4182
4183 // Start search from Store node
4184 Node* mem = store->in(MemNode::Control);
4185 if (mem->is_Proj() && mem->in(0)->is_Initialize()) {
4186
4187 InitializeNode* st_init = mem->in(0)->as_Initialize();
4188 AllocateNode* st_alloc = st_init->allocation();
4189
4190 // Make sure we are looking at the same allocation
4191 if (alloc == st_alloc) {
4192 return true;
4193 }
4194 }
4195
4196 return false;
4197 }
4198
4199 //
4200 // Update the card table and add card address to the queue
4201 //
4202 void GraphKit::g1_mark_card(IdealKit& ideal,
4203 Node* card_adr,
4204 Node* oop_store,
4205 uint oop_alias_idx,
4206 Node* index,
4207 Node* index_adr,
4208 Node* buffer,
4209 const TypeFunc* tf) {
4210
4211 Node* zero = __ ConI(0);
4212 Node* zeroX = __ ConX(0);
4213 Node* no_base = __ top();
4214 BasicType card_bt = T_BYTE;
4215 // Smash zero into card. MUST BE ORDERED WRT TO STORE
4216 __ storeCM(__ ctrl(), card_adr, zero, oop_store, oop_alias_idx, card_bt, Compile::AliasIdxRaw);
4217
4218 // Now do the queue work
4219 __ if_then(index, BoolTest::ne, zeroX); {
4220
4221 Node* next_index = _gvn.transform(new SubXNode(index, __ ConX(sizeof(intptr_t))));
4222 Node* log_addr = __ AddP(no_base, buffer, next_index);
4223
4224 // Order, see storeCM.
4225 __ store(__ ctrl(), log_addr, card_adr, T_ADDRESS, Compile::AliasIdxRaw, MemNode::unordered);
4226 __ store(__ ctrl(), index_adr, next_index, TypeX_X->basic_type(), Compile::AliasIdxRaw, MemNode::unordered);
4227
4228 } __ else_(); {
4229 __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_post), "g1_wb_post", card_adr, __ thread());
4230 } __ end_if();
4231
4232 }
4233
4234 void GraphKit::g1_write_barrier_post(Node* oop_store,
4235 Node* obj,
4236 Node* adr,
4237 uint alias_idx,
4238 Node* val,
4239 BasicType bt,
4240 bool use_precise) {
4241 // If we are writing a NULL then we need no post barrier
4242
4243 if (val != NULL && val->is_Con() && val->bottom_type() == TypePtr::NULL_PTR) {
4244 // Must be NULL
4245 const Type* t = val->bottom_type();
4246 assert(t == Type::TOP || t == TypePtr::NULL_PTR, "must be NULL");
4247 // No post barrier if writing NULLx
4248 return;
4249 }
4250
4251 if (use_ReduceInitialCardMarks() && obj == just_allocated_object(control())) {
4252 // We can skip marks on a freshly-allocated object in Eden.
4253 // Keep this code in sync with new_deferred_store_barrier() in runtime.cpp.
4254 // That routine informs GC to take appropriate compensating steps,
4255 // upon a slow-path allocation, so as to make this card-mark
4256 // elision safe.
4257 return;
4258 }
4259
4260 if (use_ReduceInitialCardMarks()
4261 && g1_can_remove_post_barrier(&_gvn, oop_store, adr)) {
4262 return;
4263 }
4264
4265 if (!use_precise) {
4266 // All card marks for a (non-array) instance are in one place:
4267 adr = obj;
4268 }
4269 // (Else it's an array (or unknown), and we want more precise card marks.)
4270 assert(adr != NULL, "");
4271
4272 IdealKit ideal(this, true);
4273
4274 Node* tls = __ thread(); // ThreadLocalStorage
4275
4276 Node* no_base = __ top();
4277 float likely = PROB_LIKELY(0.999);
4278 float unlikely = PROB_UNLIKELY(0.999);
4279 Node* young_card = __ ConI((jint)G1CardTable::g1_young_card_val());
4280 Node* dirty_card = __ ConI((jint)CardTable::dirty_card_val());
4281 Node* zeroX = __ ConX(0);
4282
4283 // Get the alias_index for raw card-mark memory
4284 const TypePtr* card_type = TypeRawPtr::BOTTOM;
4285
4286 const TypeFunc *tf = OptoRuntime::g1_wb_post_Type();
4287
4288 // Offsets into the thread
4289 const int index_offset = in_bytes(JavaThread::dirty_card_queue_offset() +
4290 DirtyCardQueue::byte_offset_of_index());
4291 const int buffer_offset = in_bytes(JavaThread::dirty_card_queue_offset() +
4292 DirtyCardQueue::byte_offset_of_buf());
4293
4294 // Pointers into the thread
4295
4296 Node* buffer_adr = __ AddP(no_base, tls, __ ConX(buffer_offset));
4297 Node* index_adr = __ AddP(no_base, tls, __ ConX(index_offset));
4298
4299 // Now some values
4300 // Use ctrl to avoid hoisting these values past a safepoint, which could
4301 // potentially reset these fields in the JavaThread.
4302 Node* index = __ load(__ ctrl(), index_adr, TypeX_X, TypeX_X->basic_type(), Compile::AliasIdxRaw);
4303 Node* buffer = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw);
4304
4305 // Convert the store obj pointer to an int prior to doing math on it
4306 // Must use ctrl to prevent "integerized oop" existing across safepoint
4307 Node* cast = __ CastPX(__ ctrl(), adr);
4308
4309 // Divide pointer by card size
4310 Node* card_offset = __ URShiftX( cast, __ ConI(CardTable::card_shift) );
4311
4312 // Combine card table base and card offset
4313 Node* card_adr = __ AddP(no_base, byte_map_base_node(), card_offset );
4314
4315 // If we know the value being stored does it cross regions?
4316
4317 if (val != NULL) {
4318 // Does the store cause us to cross regions?
4319
4320 // Should be able to do an unsigned compare of region_size instead of
4321 // and extra shift. Do we have an unsigned compare??
4322 // Node* region_size = __ ConI(1 << HeapRegion::LogOfHRGrainBytes);
4323 Node* xor_res = __ URShiftX ( __ XorX( cast, __ CastPX(__ ctrl(), val)), __ ConI(HeapRegion::LogOfHRGrainBytes));
4324
4325 // if (xor_res == 0) same region so skip
4326 __ if_then(xor_res, BoolTest::ne, zeroX); {
4327
4328 // No barrier if we are storing a NULL
4329 __ if_then(val, BoolTest::ne, null(), unlikely); {
4330
4331 // Ok must mark the card if not already dirty
4332
4333 // load the original value of the card
4334 Node* card_val = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw);
4335
4336 __ if_then(card_val, BoolTest::ne, young_card); {
4337 sync_kit(ideal);
4338 // Use Op_MemBarVolatile to achieve the effect of a StoreLoad barrier.
4339 insert_mem_bar(Op_MemBarVolatile, oop_store);
4340 __ sync_kit(this);
4341
4342 Node* card_val_reload = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw);
4343 __ if_then(card_val_reload, BoolTest::ne, dirty_card); {
4344 g1_mark_card(ideal, card_adr, oop_store, alias_idx, index, index_adr, buffer, tf);
4345 } __ end_if();
4346 } __ end_if();
4347 } __ end_if();
4348 } __ end_if();
4349 } else {
4350 // The Object.clone() intrinsic uses this path if !ReduceInitialCardMarks.
4351 // We don't need a barrier here if the destination is a newly allocated object
4352 // in Eden. Otherwise, GC verification breaks because we assume that cards in Eden
4353 // are set to 'g1_young_gen' (see G1CardTable::verify_g1_young_region()).
4354 assert(!use_ReduceInitialCardMarks(), "can only happen with card marking");
4355 Node* card_val = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw);
4356 __ if_then(card_val, BoolTest::ne, young_card); {
4357 g1_mark_card(ideal, card_adr, oop_store, alias_idx, index, index_adr, buffer, tf);
4358 } __ end_if();
4359 }
4360
4361 // Final sync IdealKit and GraphKit.
4362 final_sync(ideal);
4363 }
4364 #undef __
4365
4366
4367 Node* GraphKit::load_String_length(Node* ctrl, Node* str) {
4368 Node* len = load_array_length(load_String_value(ctrl, str));
4369 Node* coder = load_String_coder(ctrl, str);
4370 // Divide length by 2 if coder is UTF16
4371 return _gvn.transform(new RShiftINode(len, coder));
4372 }
4373
4374 Node* GraphKit::load_String_value(Node* ctrl, Node* str) {
4375 int value_offset = java_lang_String::value_offset_in_bytes();
4376 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4377 false, NULL, 0);
4378 const TypePtr* value_field_type = string_type->add_offset(value_offset);
4379 const TypeAryPtr* value_type = TypeAryPtr::make(TypePtr::NotNull,
4380 TypeAry::make(TypeInt::BYTE, TypeInt::POS),
4381 ciTypeArrayKlass::make(T_BYTE), true, 0);
4382 int value_field_idx = C->get_alias_index(value_field_type);
4383 Node* load = make_load(ctrl, basic_plus_adr(str, str, value_offset),
4384 value_type, T_OBJECT, value_field_idx, MemNode::unordered);
4385 // String.value field is known to be @Stable.
4386 if (UseImplicitStableValues) {
4387 load = cast_array_to_stable(load, value_type);
4388 }
4389 return load;
4390 }
4391
4392 Node* GraphKit::load_String_coder(Node* ctrl, Node* str) {
4393 if (!CompactStrings) {
4394 return intcon(java_lang_String::CODER_UTF16);
4395 }
4396 int coder_offset = java_lang_String::coder_offset_in_bytes();
4397 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4398 false, NULL, 0);
4399 const TypePtr* coder_field_type = string_type->add_offset(coder_offset);
4400 int coder_field_idx = C->get_alias_index(coder_field_type);
4401 return make_load(ctrl, basic_plus_adr(str, str, coder_offset),
4402 TypeInt::BYTE, T_BYTE, coder_field_idx, MemNode::unordered);
4403 }
4404
4405 void GraphKit::store_String_value(Node* ctrl, Node* str, Node* value) {
4406 int value_offset = java_lang_String::value_offset_in_bytes();
4407 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4408 false, NULL, 0);
4409 const TypePtr* value_field_type = string_type->add_offset(value_offset);
4410 store_oop_to_object(ctrl, str, basic_plus_adr(str, value_offset), value_field_type,
4411 value, TypeAryPtr::BYTES, T_OBJECT, MemNode::unordered);
4412 }
4413
4414 void GraphKit::store_String_coder(Node* ctrl, Node* str, Node* value) {
4415 int coder_offset = java_lang_String::coder_offset_in_bytes();
4416 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4417 false, NULL, 0);
4418 const TypePtr* coder_field_type = string_type->add_offset(coder_offset);
4419 int coder_field_idx = C->get_alias_index(coder_field_type);
4420 store_to_memory(ctrl, basic_plus_adr(str, coder_offset),
4421 value, T_BYTE, coder_field_idx, MemNode::unordered);
4422 }
4423
4424 // Capture src and dst memory state with a MergeMemNode
4425 Node* GraphKit::capture_memory(const TypePtr* src_type, const TypePtr* dst_type) {
4426 if (src_type == dst_type) {
4427 // Types are equal, we don't need a MergeMemNode
4428 return memory(src_type);
4429 }
4430 MergeMemNode* merge = MergeMemNode::make(map()->memory());
4431 record_for_igvn(merge); // fold it up later, if possible
4432 int src_idx = C->get_alias_index(src_type);
4433 int dst_idx = C->get_alias_index(dst_type);
4434 merge->set_memory_at(src_idx, memory(src_idx));
4435 merge->set_memory_at(dst_idx, memory(dst_idx));
4436 return merge;
4437 }
4438
4439 Node* GraphKit::compress_string(Node* src, const TypeAryPtr* src_type, Node* dst, Node* count) {
4440 assert(Matcher::match_rule_supported(Op_StrCompressedCopy), "Intrinsic not supported");
4441 assert(src_type == TypeAryPtr::BYTES || src_type == TypeAryPtr::CHARS, "invalid source type");
4442 // If input and output memory types differ, capture both states to preserve
4443 // the dependency between preceding and subsequent loads/stores.
4444 // For example, the following program:
4445 // StoreB
4446 // compress_string
4447 // LoadB
4448 // has this memory graph (use->def):
4449 // LoadB -> compress_string -> CharMem
4450 // ... -> StoreB -> ByteMem
4451 // The intrinsic hides the dependency between LoadB and StoreB, causing
4452 // the load to read from memory not containing the result of the StoreB.
4453 // The correct memory graph should look like this:
4454 // LoadB -> compress_string -> MergeMem(CharMem, StoreB(ByteMem))
4455 Node* mem = capture_memory(src_type, TypeAryPtr::BYTES);
4456 StrCompressedCopyNode* str = new StrCompressedCopyNode(control(), mem, src, dst, count);
4457 Node* res_mem = _gvn.transform(new SCMemProjNode(str));
4458 set_memory(res_mem, TypeAryPtr::BYTES);
4459 return str;
4460 }
4461
4462 void GraphKit::inflate_string(Node* src, Node* dst, const TypeAryPtr* dst_type, Node* count) {
4463 assert(Matcher::match_rule_supported(Op_StrInflatedCopy), "Intrinsic not supported");
4464 assert(dst_type == TypeAryPtr::BYTES || dst_type == TypeAryPtr::CHARS, "invalid dest type");
4465 // Capture src and dst memory (see comment in 'compress_string').
4466 Node* mem = capture_memory(TypeAryPtr::BYTES, dst_type);
4467 StrInflatedCopyNode* str = new StrInflatedCopyNode(control(), mem, src, dst, count);
4468 set_memory(_gvn.transform(str), dst_type);
4469 }
4470
4471 void GraphKit::inflate_string_slow(Node* src, Node* dst, Node* start, Node* count) {
4472 /**
4473 * int i_char = start;
4474 * for (int i_byte = 0; i_byte < count; i_byte++) {
4475 * dst[i_char++] = (char)(src[i_byte] & 0xff);
4476 * }
4477 */
4478 add_predicate();
4479 RegionNode* head = new RegionNode(3);
4480 head->init_req(1, control());
4481 gvn().set_type(head, Type::CONTROL);
4482 record_for_igvn(head);
4483
4484 Node* i_byte = new PhiNode(head, TypeInt::INT);
4485 i_byte->init_req(1, intcon(0));
4486 gvn().set_type(i_byte, TypeInt::INT);
4487 record_for_igvn(i_byte);
4488
4489 Node* i_char = new PhiNode(head, TypeInt::INT);
4490 i_char->init_req(1, start);
4491 gvn().set_type(i_char, TypeInt::INT);
4492 record_for_igvn(i_char);
4493
4494 Node* mem = PhiNode::make(head, memory(TypeAryPtr::BYTES), Type::MEMORY, TypeAryPtr::BYTES);
4495 gvn().set_type(mem, Type::MEMORY);
4496 record_for_igvn(mem);
4497 set_control(head);
4498 set_memory(mem, TypeAryPtr::BYTES);
4499 Node* ch = load_array_element(control(), src, i_byte, TypeAryPtr::BYTES);
4500 Node* st = store_to_memory(control(), array_element_address(dst, i_char, T_BYTE),
4501 AndI(ch, intcon(0xff)), T_CHAR, TypeAryPtr::BYTES, MemNode::unordered,
4502 false, false, true /* mismatched */);
4503
4504 IfNode* iff = create_and_map_if(head, Bool(CmpI(i_byte, count), BoolTest::lt), PROB_FAIR, COUNT_UNKNOWN);
4505 head->init_req(2, IfTrue(iff));
4506 mem->init_req(2, st);
4507 i_byte->init_req(2, AddI(i_byte, intcon(1)));
4508 i_char->init_req(2, AddI(i_char, intcon(2)));
4509
4510 set_control(IfFalse(iff));
4511 set_memory(st, TypeAryPtr::BYTES);
4512 }
4513
4514 Node* GraphKit::make_constant_from_field(ciField* field, Node* obj) {
4515 if (!field->is_constant()) {
4516 return NULL; // Field not marked as constant.
4517 }
4518 ciInstance* holder = NULL;
4519 if (!field->is_static()) {
4520 ciObject* const_oop = obj->bottom_type()->is_oopptr()->const_oop();
4521 if (const_oop != NULL && const_oop->is_instance()) {
4522 holder = const_oop->as_instance();
4523 }
4524 }
4525 const Type* con_type = Type::make_constant_from_field(field, holder, field->layout_type(),
4526 /*is_unsigned_load=*/false);
4527 if (con_type != NULL) {
4528 return makecon(con_type);
4529 }
4530 return NULL;
4531 }
4532
4533 Node* GraphKit::cast_array_to_stable(Node* ary, const TypeAryPtr* ary_type) {
4534 // Reify the property as a CastPP node in Ideal graph to comply with monotonicity
4535 // assumption of CCP analysis.
4536 return _gvn.transform(new CastPPNode(ary, ary_type->cast_to_stable(true)));
4537 }