1 /*
2 * Copyright (c) 2001, 2025, 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 "ci/ciUtilities.hpp"
26 #include "classfile/javaClasses.hpp"
27 #include "ci/ciObjArray.hpp"
28 #include "asm/register.hpp"
29 #include "compiler/compileLog.hpp"
30 #include "gc/shared/barrierSet.hpp"
31 #include "gc/shared/c2/barrierSetC2.hpp"
32 #include "interpreter/interpreter.hpp"
33 #include "memory/resourceArea.hpp"
34 #include "opto/addnode.hpp"
35 #include "opto/castnode.hpp"
36 #include "opto/convertnode.hpp"
37 #include "opto/graphKit.hpp"
38 #include "opto/idealKit.hpp"
39 #include "opto/intrinsicnode.hpp"
40 #include "opto/locknode.hpp"
41 #include "opto/machnode.hpp"
42 #include "opto/opaquenode.hpp"
43 #include "opto/parse.hpp"
44 #include "opto/rootnode.hpp"
45 #include "opto/runtime.hpp"
46 #include "opto/subtypenode.hpp"
47 #include "runtime/deoptimization.hpp"
48 #include "runtime/sharedRuntime.hpp"
49 #include "utilities/bitMap.inline.hpp"
50 #include "utilities/powerOfTwo.hpp"
51 #include "utilities/growableArray.hpp"
52
53 //----------------------------GraphKit-----------------------------------------
54 // Main utility constructor.
55 GraphKit::GraphKit(JVMState* jvms)
56 : Phase(Phase::Parser),
57 _env(C->env()),
58 _gvn(*C->initial_gvn()),
59 _barrier_set(BarrierSet::barrier_set()->barrier_set_c2())
60 {
61 _exceptions = jvms->map()->next_exception();
62 if (_exceptions != nullptr) jvms->map()->set_next_exception(nullptr);
63 set_jvms(jvms);
64 }
65
66 // Private constructor for parser.
67 GraphKit::GraphKit()
68 : Phase(Phase::Parser),
69 _env(C->env()),
70 _gvn(*C->initial_gvn()),
71 _barrier_set(BarrierSet::barrier_set()->barrier_set_c2())
72 {
73 _exceptions = nullptr;
74 set_map(nullptr);
75 debug_only(_sp = -99);
76 debug_only(set_bci(-99));
77 }
78
79
80
81 //---------------------------clean_stack---------------------------------------
82 // Clear away rubbish from the stack area of the JVM state.
83 // This destroys any arguments that may be waiting on the stack.
84 void GraphKit::clean_stack(int from_sp) {
85 SafePointNode* map = this->map();
86 JVMState* jvms = this->jvms();
87 int stk_size = jvms->stk_size();
88 int stkoff = jvms->stkoff();
89 Node* top = this->top();
90 for (int i = from_sp; i < stk_size; i++) {
91 if (map->in(stkoff + i) != top) {
92 map->set_req(stkoff + i, top);
93 }
94 }
95 }
96
97
98 //--------------------------------sync_jvms-----------------------------------
99 // Make sure our current jvms agrees with our parse state.
100 JVMState* GraphKit::sync_jvms() const {
101 JVMState* jvms = this->jvms();
102 jvms->set_bci(bci()); // Record the new bci in the JVMState
103 jvms->set_sp(sp()); // Record the new sp in the JVMState
104 assert(jvms_in_sync(), "jvms is now in sync");
105 return jvms;
106 }
107
108 //--------------------------------sync_jvms_for_reexecute---------------------
109 // Make sure our current jvms agrees with our parse state. This version
110 // uses the reexecute_sp for reexecuting bytecodes.
111 JVMState* GraphKit::sync_jvms_for_reexecute() {
112 JVMState* jvms = this->jvms();
113 jvms->set_bci(bci()); // Record the new bci in the JVMState
114 jvms->set_sp(reexecute_sp()); // Record the new sp in the JVMState
115 return jvms;
116 }
117
118 #ifdef ASSERT
119 bool GraphKit::jvms_in_sync() const {
120 Parse* parse = is_Parse();
121 if (parse == nullptr) {
122 if (bci() != jvms()->bci()) return false;
123 if (sp() != (int)jvms()->sp()) return false;
124 return true;
125 }
126 if (jvms()->method() != parse->method()) return false;
127 if (jvms()->bci() != parse->bci()) return false;
128 int jvms_sp = jvms()->sp();
129 if (jvms_sp != parse->sp()) return false;
130 int jvms_depth = jvms()->depth();
131 if (jvms_depth != parse->depth()) return false;
132 return true;
133 }
134
135 // Local helper checks for special internal merge points
136 // used to accumulate and merge exception states.
137 // They are marked by the region's in(0) edge being the map itself.
138 // Such merge points must never "escape" into the parser at large,
139 // until they have been handed to gvn.transform.
140 static bool is_hidden_merge(Node* reg) {
141 if (reg == nullptr) return false;
142 if (reg->is_Phi()) {
143 reg = reg->in(0);
144 if (reg == nullptr) return false;
145 }
146 return reg->is_Region() && reg->in(0) != nullptr && reg->in(0)->is_Root();
147 }
148
149 void GraphKit::verify_map() const {
150 if (map() == nullptr) return; // null map is OK
151 assert(map()->req() <= jvms()->endoff(), "no extra garbage on map");
152 assert(!map()->has_exceptions(), "call add_exception_states_from 1st");
153 assert(!is_hidden_merge(control()), "call use_exception_state, not set_map");
154 }
155
156 void GraphKit::verify_exception_state(SafePointNode* ex_map) {
157 assert(ex_map->next_exception() == nullptr, "not already part of a chain");
158 assert(has_saved_ex_oop(ex_map), "every exception state has an ex_oop");
159 }
160 #endif
161
162 //---------------------------stop_and_kill_map---------------------------------
163 // Set _map to null, signalling a stop to further bytecode execution.
164 // First smash the current map's control to a constant, to mark it dead.
165 void GraphKit::stop_and_kill_map() {
166 SafePointNode* dead_map = stop();
167 if (dead_map != nullptr) {
168 dead_map->disconnect_inputs(C); // Mark the map as killed.
169 assert(dead_map->is_killed(), "must be so marked");
170 }
171 }
172
173
174 //--------------------------------stopped--------------------------------------
175 // Tell if _map is null, or control is top.
176 bool GraphKit::stopped() {
177 if (map() == nullptr) return true;
178 else if (control() == top()) return true;
179 else return false;
180 }
181
182
183 //-----------------------------has_exception_handler----------------------------------
184 // Tell if this method or any caller method has exception handlers.
185 bool GraphKit::has_exception_handler() {
186 for (JVMState* jvmsp = jvms(); jvmsp != nullptr; jvmsp = jvmsp->caller()) {
187 if (jvmsp->has_method() && jvmsp->method()->has_exception_handlers()) {
188 return true;
189 }
190 }
191 return false;
192 }
193
194 //------------------------------save_ex_oop------------------------------------
195 // Save an exception without blowing stack contents or other JVM state.
196 void GraphKit::set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop) {
197 assert(!has_saved_ex_oop(ex_map), "clear ex-oop before setting again");
198 ex_map->add_req(ex_oop);
199 debug_only(verify_exception_state(ex_map));
200 }
201
202 inline static Node* common_saved_ex_oop(SafePointNode* ex_map, bool clear_it) {
203 assert(GraphKit::has_saved_ex_oop(ex_map), "ex_oop must be there");
204 Node* ex_oop = ex_map->in(ex_map->req()-1);
205 if (clear_it) ex_map->del_req(ex_map->req()-1);
206 return ex_oop;
207 }
208
209 //-----------------------------saved_ex_oop------------------------------------
210 // Recover a saved exception from its map.
211 Node* GraphKit::saved_ex_oop(SafePointNode* ex_map) {
212 return common_saved_ex_oop(ex_map, false);
213 }
214
215 //--------------------------clear_saved_ex_oop---------------------------------
216 // Erase a previously saved exception from its map.
217 Node* GraphKit::clear_saved_ex_oop(SafePointNode* ex_map) {
218 return common_saved_ex_oop(ex_map, true);
219 }
220
221 #ifdef ASSERT
222 //---------------------------has_saved_ex_oop----------------------------------
223 // Erase a previously saved exception from its map.
224 bool GraphKit::has_saved_ex_oop(SafePointNode* ex_map) {
225 return ex_map->req() == ex_map->jvms()->endoff()+1;
226 }
227 #endif
228
229 //-------------------------make_exception_state--------------------------------
230 // Turn the current JVM state into an exception state, appending the ex_oop.
231 SafePointNode* GraphKit::make_exception_state(Node* ex_oop) {
232 sync_jvms();
233 SafePointNode* ex_map = stop(); // do not manipulate this map any more
234 set_saved_ex_oop(ex_map, ex_oop);
235 return ex_map;
236 }
237
238
239 //--------------------------add_exception_state--------------------------------
240 // Add an exception to my list of exceptions.
241 void GraphKit::add_exception_state(SafePointNode* ex_map) {
242 if (ex_map == nullptr || ex_map->control() == top()) {
243 return;
244 }
245 #ifdef ASSERT
246 verify_exception_state(ex_map);
247 if (has_exceptions()) {
248 assert(ex_map->jvms()->same_calls_as(_exceptions->jvms()), "all collected exceptions must come from the same place");
249 }
250 #endif
251
252 // If there is already an exception of exactly this type, merge with it.
253 // In particular, null-checks and other low-level exceptions common up here.
254 Node* ex_oop = saved_ex_oop(ex_map);
255 const Type* ex_type = _gvn.type(ex_oop);
256 if (ex_oop == top()) {
257 // No action needed.
258 return;
259 }
260 assert(ex_type->isa_instptr(), "exception must be an instance");
261 for (SafePointNode* e2 = _exceptions; e2 != nullptr; e2 = e2->next_exception()) {
262 const Type* ex_type2 = _gvn.type(saved_ex_oop(e2));
263 // We check sp also because call bytecodes can generate exceptions
264 // both before and after arguments are popped!
265 if (ex_type2 == ex_type
266 && e2->_jvms->sp() == ex_map->_jvms->sp()) {
267 combine_exception_states(ex_map, e2);
268 return;
269 }
270 }
271
272 // No pre-existing exception of the same type. Chain it on the list.
273 push_exception_state(ex_map);
274 }
275
276 //-----------------------add_exception_states_from-----------------------------
277 void GraphKit::add_exception_states_from(JVMState* jvms) {
278 SafePointNode* ex_map = jvms->map()->next_exception();
279 if (ex_map != nullptr) {
280 jvms->map()->set_next_exception(nullptr);
281 for (SafePointNode* next_map; ex_map != nullptr; ex_map = next_map) {
282 next_map = ex_map->next_exception();
283 ex_map->set_next_exception(nullptr);
284 add_exception_state(ex_map);
285 }
286 }
287 }
288
289 //-----------------------transfer_exceptions_into_jvms-------------------------
290 JVMState* GraphKit::transfer_exceptions_into_jvms() {
291 if (map() == nullptr) {
292 // We need a JVMS to carry the exceptions, but the map has gone away.
293 // Create a scratch JVMS, cloned from any of the exception states...
294 if (has_exceptions()) {
295 _map = _exceptions;
296 _map = clone_map();
297 _map->set_next_exception(nullptr);
298 clear_saved_ex_oop(_map);
299 debug_only(verify_map());
300 } else {
301 // ...or created from scratch
302 JVMState* jvms = new (C) JVMState(_method, nullptr);
303 jvms->set_bci(_bci);
304 jvms->set_sp(_sp);
305 jvms->set_map(new SafePointNode(TypeFunc::Parms, jvms));
306 set_jvms(jvms);
307 for (uint i = 0; i < map()->req(); i++) map()->init_req(i, top());
308 set_all_memory(top());
309 while (map()->req() < jvms->endoff()) map()->add_req(top());
310 }
311 // (This is a kludge, in case you didn't notice.)
312 set_control(top());
313 }
314 JVMState* jvms = sync_jvms();
315 assert(!jvms->map()->has_exceptions(), "no exceptions on this map yet");
316 jvms->map()->set_next_exception(_exceptions);
317 _exceptions = nullptr; // done with this set of exceptions
318 return jvms;
319 }
320
321 static inline void add_n_reqs(Node* dstphi, Node* srcphi) {
322 assert(is_hidden_merge(dstphi), "must be a special merge node");
323 assert(is_hidden_merge(srcphi), "must be a special merge node");
324 uint limit = srcphi->req();
325 for (uint i = PhiNode::Input; i < limit; i++) {
326 dstphi->add_req(srcphi->in(i));
327 }
328 }
329 static inline void add_one_req(Node* dstphi, Node* src) {
330 assert(is_hidden_merge(dstphi), "must be a special merge node");
331 assert(!is_hidden_merge(src), "must not be a special merge node");
332 dstphi->add_req(src);
333 }
334
335 //-----------------------combine_exception_states------------------------------
336 // This helper function combines exception states by building phis on a
337 // specially marked state-merging region. These regions and phis are
338 // untransformed, and can build up gradually. The region is marked by
339 // having a control input of its exception map, rather than null. Such
340 // regions do not appear except in this function, and in use_exception_state.
341 void GraphKit::combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map) {
342 if (failing_internal()) {
343 return; // dying anyway...
344 }
345 JVMState* ex_jvms = ex_map->_jvms;
346 assert(ex_jvms->same_calls_as(phi_map->_jvms), "consistent call chains");
347 assert(ex_jvms->stkoff() == phi_map->_jvms->stkoff(), "matching locals");
348 assert(ex_jvms->sp() == phi_map->_jvms->sp(), "matching stack sizes");
349 assert(ex_jvms->monoff() == phi_map->_jvms->monoff(), "matching JVMS");
350 assert(ex_jvms->scloff() == phi_map->_jvms->scloff(), "matching scalar replaced objects");
351 assert(ex_map->req() == phi_map->req(), "matching maps");
352 uint tos = ex_jvms->stkoff() + ex_jvms->sp();
353 Node* hidden_merge_mark = root();
354 Node* region = phi_map->control();
355 MergeMemNode* phi_mem = phi_map->merged_memory();
356 MergeMemNode* ex_mem = ex_map->merged_memory();
357 if (region->in(0) != hidden_merge_mark) {
358 // The control input is not (yet) a specially-marked region in phi_map.
359 // Make it so, and build some phis.
360 region = new RegionNode(2);
361 _gvn.set_type(region, Type::CONTROL);
362 region->set_req(0, hidden_merge_mark); // marks an internal ex-state
363 region->init_req(1, phi_map->control());
364 phi_map->set_control(region);
365 Node* io_phi = PhiNode::make(region, phi_map->i_o(), Type::ABIO);
366 record_for_igvn(io_phi);
367 _gvn.set_type(io_phi, Type::ABIO);
368 phi_map->set_i_o(io_phi);
369 for (MergeMemStream mms(phi_mem); mms.next_non_empty(); ) {
370 Node* m = mms.memory();
371 Node* m_phi = PhiNode::make(region, m, Type::MEMORY, mms.adr_type(C));
372 record_for_igvn(m_phi);
373 _gvn.set_type(m_phi, Type::MEMORY);
374 mms.set_memory(m_phi);
375 }
376 }
377
378 // Either or both of phi_map and ex_map might already be converted into phis.
379 Node* ex_control = ex_map->control();
380 // if there is special marking on ex_map also, we add multiple edges from src
381 bool add_multiple = (ex_control->in(0) == hidden_merge_mark);
382 // how wide was the destination phi_map, originally?
383 uint orig_width = region->req();
384
385 if (add_multiple) {
386 add_n_reqs(region, ex_control);
387 add_n_reqs(phi_map->i_o(), ex_map->i_o());
388 } else {
389 // ex_map has no merges, so we just add single edges everywhere
390 add_one_req(region, ex_control);
391 add_one_req(phi_map->i_o(), ex_map->i_o());
392 }
393 for (MergeMemStream mms(phi_mem, ex_mem); mms.next_non_empty2(); ) {
394 if (mms.is_empty()) {
395 // get a copy of the base memory, and patch some inputs into it
396 const TypePtr* adr_type = mms.adr_type(C);
397 Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
398 assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
399 mms.set_memory(phi);
400 // Prepare to append interesting stuff onto the newly sliced phi:
401 while (phi->req() > orig_width) phi->del_req(phi->req()-1);
402 }
403 // Append stuff from ex_map:
404 if (add_multiple) {
405 add_n_reqs(mms.memory(), mms.memory2());
406 } else {
407 add_one_req(mms.memory(), mms.memory2());
408 }
409 }
410 uint limit = ex_map->req();
411 for (uint i = TypeFunc::Parms; i < limit; i++) {
412 // Skip everything in the JVMS after tos. (The ex_oop follows.)
413 if (i == tos) i = ex_jvms->monoff();
414 Node* src = ex_map->in(i);
415 Node* dst = phi_map->in(i);
416 if (src != dst) {
417 PhiNode* phi;
418 if (dst->in(0) != region) {
419 dst = phi = PhiNode::make(region, dst, _gvn.type(dst));
420 record_for_igvn(phi);
421 _gvn.set_type(phi, phi->type());
422 phi_map->set_req(i, dst);
423 // Prepare to append interesting stuff onto the new phi:
424 while (dst->req() > orig_width) dst->del_req(dst->req()-1);
425 } else {
426 assert(dst->is_Phi(), "nobody else uses a hidden region");
427 phi = dst->as_Phi();
428 }
429 if (add_multiple && src->in(0) == ex_control) {
430 // Both are phis.
431 add_n_reqs(dst, src);
432 } else {
433 while (dst->req() < region->req()) add_one_req(dst, src);
434 }
435 const Type* srctype = _gvn.type(src);
436 if (phi->type() != srctype) {
437 const Type* dsttype = phi->type()->meet_speculative(srctype);
438 if (phi->type() != dsttype) {
439 phi->set_type(dsttype);
440 _gvn.set_type(phi, dsttype);
441 }
442 }
443 }
444 }
445 phi_map->merge_replaced_nodes_with(ex_map);
446 }
447
448 //--------------------------use_exception_state--------------------------------
449 Node* GraphKit::use_exception_state(SafePointNode* phi_map) {
450 if (failing_internal()) { stop(); return top(); }
451 Node* region = phi_map->control();
452 Node* hidden_merge_mark = root();
453 assert(phi_map->jvms()->map() == phi_map, "sanity: 1-1 relation");
454 Node* ex_oop = clear_saved_ex_oop(phi_map);
455 if (region->in(0) == hidden_merge_mark) {
456 // Special marking for internal ex-states. Process the phis now.
457 region->set_req(0, region); // now it's an ordinary region
458 set_jvms(phi_map->jvms()); // ...so now we can use it as a map
459 // Note: Setting the jvms also sets the bci and sp.
460 set_control(_gvn.transform(region));
461 uint tos = jvms()->stkoff() + sp();
462 for (uint i = 1; i < tos; i++) {
463 Node* x = phi_map->in(i);
464 if (x->in(0) == region) {
465 assert(x->is_Phi(), "expected a special phi");
466 phi_map->set_req(i, _gvn.transform(x));
467 }
468 }
469 for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
470 Node* x = mms.memory();
471 if (x->in(0) == region) {
472 assert(x->is_Phi(), "nobody else uses a hidden region");
473 mms.set_memory(_gvn.transform(x));
474 }
475 }
476 if (ex_oop->in(0) == region) {
477 assert(ex_oop->is_Phi(), "expected a special phi");
478 ex_oop = _gvn.transform(ex_oop);
479 }
480 } else {
481 set_jvms(phi_map->jvms());
482 }
483
484 assert(!is_hidden_merge(phi_map->control()), "hidden ex. states cleared");
485 assert(!is_hidden_merge(phi_map->i_o()), "hidden ex. states cleared");
486 return ex_oop;
487 }
488
489 //---------------------------------java_bc-------------------------------------
490 Bytecodes::Code GraphKit::java_bc() const {
491 ciMethod* method = this->method();
492 int bci = this->bci();
493 if (method != nullptr && bci != InvocationEntryBci)
494 return method->java_code_at_bci(bci);
495 else
496 return Bytecodes::_illegal;
497 }
498
499 void GraphKit::uncommon_trap_if_should_post_on_exceptions(Deoptimization::DeoptReason reason,
500 bool must_throw) {
501 // if the exception capability is set, then we will generate code
502 // to check the JavaThread.should_post_on_exceptions flag to see
503 // if we actually need to report exception events (for this
504 // thread). If we don't need to report exception events, we will
505 // take the normal fast path provided by add_exception_events. If
506 // exception event reporting is enabled for this thread, we will
507 // take the uncommon_trap in the BuildCutout below.
508
509 // first must access the should_post_on_exceptions_flag in this thread's JavaThread
510 Node* jthread = _gvn.transform(new ThreadLocalNode());
511 Node* adr = basic_plus_adr(top(), jthread, in_bytes(JavaThread::should_post_on_exceptions_flag_offset()));
512 Node* should_post_flag = make_load(control(), adr, TypeInt::INT, T_INT, MemNode::unordered);
513
514 // Test the should_post_on_exceptions_flag vs. 0
515 Node* chk = _gvn.transform( new CmpINode(should_post_flag, intcon(0)) );
516 Node* tst = _gvn.transform( new BoolNode(chk, BoolTest::eq) );
517
518 // Branch to slow_path if should_post_on_exceptions_flag was true
519 { BuildCutout unless(this, tst, PROB_MAX);
520 // Do not try anything fancy if we're notifying the VM on every throw.
521 // Cf. case Bytecodes::_athrow in parse2.cpp.
522 uncommon_trap(reason, Deoptimization::Action_none,
523 (ciKlass*)nullptr, (char*)nullptr, must_throw);
524 }
525
526 }
527
528 //------------------------------builtin_throw----------------------------------
529 void GraphKit::builtin_throw(Deoptimization::DeoptReason reason) {
530 bool must_throw = true;
531
532 // If this particular condition has not yet happened at this
533 // bytecode, then use the uncommon trap mechanism, and allow for
534 // a future recompilation if several traps occur here.
535 // If the throw is hot, try to use a more complicated inline mechanism
536 // which keeps execution inside the compiled code.
537 bool treat_throw_as_hot = false;
538 ciMethodData* md = method()->method_data();
539
540 if (ProfileTraps) {
541 if (too_many_traps(reason)) {
542 treat_throw_as_hot = true;
543 }
544 // (If there is no MDO at all, assume it is early in
545 // execution, and that any deopts are part of the
546 // startup transient, and don't need to be remembered.)
547
548 // Also, if there is a local exception handler, treat all throws
549 // as hot if there has been at least one in this method.
550 if (C->trap_count(reason) != 0
551 && method()->method_data()->trap_count(reason) != 0
552 && has_exception_handler()) {
553 treat_throw_as_hot = true;
554 }
555 }
556
557 // If this throw happens frequently, an uncommon trap might cause
558 // a performance pothole. If there is a local exception handler,
559 // and if this particular bytecode appears to be deoptimizing often,
560 // let us handle the throw inline, with a preconstructed instance.
561 // Note: If the deopt count has blown up, the uncommon trap
562 // runtime is going to flush this nmethod, not matter what.
563 if (treat_throw_as_hot && method()->can_omit_stack_trace()) {
564 // If the throw is local, we use a pre-existing instance and
565 // punt on the backtrace. This would lead to a missing backtrace
566 // (a repeat of 4292742) if the backtrace object is ever asked
567 // for its backtrace.
568 // Fixing this remaining case of 4292742 requires some flavor of
569 // escape analysis. Leave that for the future.
570 ciInstance* ex_obj = nullptr;
571 switch (reason) {
572 case Deoptimization::Reason_null_check:
573 ex_obj = env()->NullPointerException_instance();
574 break;
575 case Deoptimization::Reason_div0_check:
576 ex_obj = env()->ArithmeticException_instance();
577 break;
578 case Deoptimization::Reason_range_check:
579 ex_obj = env()->ArrayIndexOutOfBoundsException_instance();
580 break;
581 case Deoptimization::Reason_class_check:
582 ex_obj = env()->ClassCastException_instance();
583 break;
584 case Deoptimization::Reason_array_check:
585 ex_obj = env()->ArrayStoreException_instance();
586 break;
587 default:
588 break;
589 }
590 if (failing()) { stop(); return; } // exception allocation might fail
591 if (ex_obj != nullptr) {
592 if (env()->jvmti_can_post_on_exceptions()) {
593 // check if we must post exception events, take uncommon trap if so
594 uncommon_trap_if_should_post_on_exceptions(reason, must_throw);
595 // here if should_post_on_exceptions is false
596 // continue on with the normal codegen
597 }
598
599 // Cheat with a preallocated exception object.
600 if (C->log() != nullptr)
601 C->log()->elem("hot_throw preallocated='1' reason='%s'",
602 Deoptimization::trap_reason_name(reason));
603 const TypeInstPtr* ex_con = TypeInstPtr::make(ex_obj);
604 Node* ex_node = _gvn.transform(ConNode::make(ex_con));
605
606 // Clear the detail message of the preallocated exception object.
607 // Weblogic sometimes mutates the detail message of exceptions
608 // using reflection.
609 int offset = java_lang_Throwable::get_detailMessage_offset();
610 const TypePtr* adr_typ = ex_con->add_offset(offset);
611
612 Node *adr = basic_plus_adr(ex_node, ex_node, offset);
613 const TypeOopPtr* val_type = TypeOopPtr::make_from_klass(env()->String_klass());
614 Node *store = access_store_at(ex_node, adr, adr_typ, null(), val_type, T_OBJECT, IN_HEAP);
615
616 if (!method()->has_exception_handlers()) {
617 // We don't need to preserve the stack if there's no handler as the entire frame is going to be popped anyway.
618 // This prevents issues with exception handling and late inlining.
619 set_sp(0);
620 clean_stack(0);
621 }
622
623 add_exception_state(make_exception_state(ex_node));
624 return;
625 }
626 }
627
628 // %%% Maybe add entry to OptoRuntime which directly throws the exc.?
629 // It won't be much cheaper than bailing to the interp., since we'll
630 // have to pass up all the debug-info, and the runtime will have to
631 // create the stack trace.
632
633 // Usual case: Bail to interpreter.
634 // Reserve the right to recompile if we haven't seen anything yet.
635
636 ciMethod* m = Deoptimization::reason_is_speculate(reason) ? C->method() : nullptr;
637 Deoptimization::DeoptAction action = Deoptimization::Action_maybe_recompile;
638 if (treat_throw_as_hot
639 && (method()->method_data()->trap_recompiled_at(bci(), m)
640 || C->too_many_traps(reason))) {
641 // We cannot afford to take more traps here. Suffer in the interpreter.
642 if (C->log() != nullptr)
643 C->log()->elem("hot_throw preallocated='0' reason='%s' mcount='%d'",
644 Deoptimization::trap_reason_name(reason),
645 C->trap_count(reason));
646 action = Deoptimization::Action_none;
647 }
648
649 // "must_throw" prunes the JVM state to include only the stack, if there
650 // are no local exception handlers. This should cut down on register
651 // allocation time and code size, by drastically reducing the number
652 // of in-edges on the call to the uncommon trap.
653
654 uncommon_trap(reason, action, (ciKlass*)nullptr, (char*)nullptr, must_throw);
655 }
656
657
658 //----------------------------PreserveJVMState---------------------------------
659 PreserveJVMState::PreserveJVMState(GraphKit* kit, bool clone_map) {
660 debug_only(kit->verify_map());
661 _kit = kit;
662 _map = kit->map(); // preserve the map
663 _sp = kit->sp();
664 kit->set_map(clone_map ? kit->clone_map() : nullptr);
665 #ifdef ASSERT
666 _bci = kit->bci();
667 Parse* parser = kit->is_Parse();
668 int block = (parser == nullptr || parser->block() == nullptr) ? -1 : parser->block()->rpo();
669 _block = block;
670 #endif
671 }
672 PreserveJVMState::~PreserveJVMState() {
673 GraphKit* kit = _kit;
674 #ifdef ASSERT
675 assert(kit->bci() == _bci, "bci must not shift");
676 Parse* parser = kit->is_Parse();
677 int block = (parser == nullptr || parser->block() == nullptr) ? -1 : parser->block()->rpo();
678 assert(block == _block, "block must not shift");
679 #endif
680 kit->set_map(_map);
681 kit->set_sp(_sp);
682 }
683
684
685 //-----------------------------BuildCutout-------------------------------------
686 BuildCutout::BuildCutout(GraphKit* kit, Node* p, float prob, float cnt)
687 : PreserveJVMState(kit)
688 {
689 assert(p->is_Con() || p->is_Bool(), "test must be a bool");
690 SafePointNode* outer_map = _map; // preserved map is caller's
691 SafePointNode* inner_map = kit->map();
692 IfNode* iff = kit->create_and_map_if(outer_map->control(), p, prob, cnt);
693 outer_map->set_control(kit->gvn().transform( new IfTrueNode(iff) ));
694 inner_map->set_control(kit->gvn().transform( new IfFalseNode(iff) ));
695 }
696 BuildCutout::~BuildCutout() {
697 GraphKit* kit = _kit;
698 assert(kit->stopped(), "cutout code must stop, throw, return, etc.");
699 }
700
701 //---------------------------PreserveReexecuteState----------------------------
702 PreserveReexecuteState::PreserveReexecuteState(GraphKit* kit) {
703 assert(!kit->stopped(), "must call stopped() before");
704 _kit = kit;
705 _sp = kit->sp();
706 _reexecute = kit->jvms()->_reexecute;
707 }
708 PreserveReexecuteState::~PreserveReexecuteState() {
709 if (_kit->stopped()) return;
710 _kit->jvms()->_reexecute = _reexecute;
711 _kit->set_sp(_sp);
712 }
713
714 //------------------------------clone_map--------------------------------------
715 // Implementation of PreserveJVMState
716 //
717 // Only clone_map(...) here. If this function is only used in the
718 // PreserveJVMState class we may want to get rid of this extra
719 // function eventually and do it all there.
720
721 SafePointNode* GraphKit::clone_map() {
722 if (map() == nullptr) return nullptr;
723
724 // Clone the memory edge first
725 Node* mem = MergeMemNode::make(map()->memory());
726 gvn().set_type_bottom(mem);
727
728 SafePointNode *clonemap = (SafePointNode*)map()->clone();
729 JVMState* jvms = this->jvms();
730 JVMState* clonejvms = jvms->clone_shallow(C);
731 clonemap->set_memory(mem);
732 clonemap->set_jvms(clonejvms);
733 clonejvms->set_map(clonemap);
734 record_for_igvn(clonemap);
735 gvn().set_type_bottom(clonemap);
736 return clonemap;
737 }
738
739 //-----------------------------destruct_map_clone------------------------------
740 //
741 // Order of destruct is important to increase the likelyhood that memory can be re-used. We need
742 // to destruct/free/delete in the exact opposite order as clone_map().
743 void GraphKit::destruct_map_clone(SafePointNode* sfp) {
744 if (sfp == nullptr) return;
745
746 Node* mem = sfp->memory();
747 JVMState* jvms = sfp->jvms();
748
749 if (jvms != nullptr) {
750 delete jvms;
751 }
752
753 remove_for_igvn(sfp);
754 gvn().clear_type(sfp);
755 sfp->destruct(&_gvn);
756
757 if (mem != nullptr) {
758 gvn().clear_type(mem);
759 mem->destruct(&_gvn);
760 }
761 }
762
763 //-----------------------------set_map_clone-----------------------------------
764 void GraphKit::set_map_clone(SafePointNode* m) {
765 _map = m;
766 _map = clone_map();
767 _map->set_next_exception(nullptr);
768 debug_only(verify_map());
769 }
770
771
772 //----------------------------kill_dead_locals---------------------------------
773 // Detect any locals which are known to be dead, and force them to top.
774 void GraphKit::kill_dead_locals() {
775 // Consult the liveness information for the locals. If any
776 // of them are unused, then they can be replaced by top(). This
777 // should help register allocation time and cut down on the size
778 // of the deoptimization information.
779
780 // This call is made from many of the bytecode handling
781 // subroutines called from the Big Switch in do_one_bytecode.
782 // Every bytecode which might include a slow path is responsible
783 // for killing its dead locals. The more consistent we
784 // are about killing deads, the fewer useless phis will be
785 // constructed for them at various merge points.
786
787 // bci can be -1 (InvocationEntryBci). We return the entry
788 // liveness for the method.
789
790 if (method() == nullptr || method()->code_size() == 0) {
791 // We are building a graph for a call to a native method.
792 // All locals are live.
793 return;
794 }
795
796 ResourceMark rm;
797
798 // Consult the liveness information for the locals. If any
799 // of them are unused, then they can be replaced by top(). This
800 // should help register allocation time and cut down on the size
801 // of the deoptimization information.
802 MethodLivenessResult live_locals = method()->liveness_at_bci(bci());
803
804 int len = (int)live_locals.size();
805 assert(len <= jvms()->loc_size(), "too many live locals");
806 for (int local = 0; local < len; local++) {
807 if (!live_locals.at(local)) {
808 set_local(local, top());
809 }
810 }
811 }
812
813 #ifdef ASSERT
814 //-------------------------dead_locals_are_killed------------------------------
815 // Return true if all dead locals are set to top in the map.
816 // Used to assert "clean" debug info at various points.
817 bool GraphKit::dead_locals_are_killed() {
818 if (method() == nullptr || method()->code_size() == 0) {
819 // No locals need to be dead, so all is as it should be.
820 return true;
821 }
822
823 // Make sure somebody called kill_dead_locals upstream.
824 ResourceMark rm;
825 for (JVMState* jvms = this->jvms(); jvms != nullptr; jvms = jvms->caller()) {
826 if (jvms->loc_size() == 0) continue; // no locals to consult
827 SafePointNode* map = jvms->map();
828 ciMethod* method = jvms->method();
829 int bci = jvms->bci();
830 if (jvms == this->jvms()) {
831 bci = this->bci(); // it might not yet be synched
832 }
833 MethodLivenessResult live_locals = method->liveness_at_bci(bci);
834 int len = (int)live_locals.size();
835 if (!live_locals.is_valid() || len == 0)
836 // This method is trivial, or is poisoned by a breakpoint.
837 return true;
838 assert(len == jvms->loc_size(), "live map consistent with locals map");
839 for (int local = 0; local < len; local++) {
840 if (!live_locals.at(local) && map->local(jvms, local) != top()) {
841 if (PrintMiscellaneous && (Verbose || WizardMode)) {
842 tty->print_cr("Zombie local %d: ", local);
843 jvms->dump();
844 }
845 return false;
846 }
847 }
848 }
849 return true;
850 }
851
852 #endif //ASSERT
853
854 // Helper function for enforcing certain bytecodes to reexecute if deoptimization happens.
855 static bool should_reexecute_implied_by_bytecode(JVMState *jvms, bool is_anewarray) {
856 ciMethod* cur_method = jvms->method();
857 int cur_bci = jvms->bci();
858 if (cur_method != nullptr && cur_bci != InvocationEntryBci) {
859 Bytecodes::Code code = cur_method->java_code_at_bci(cur_bci);
860 return Interpreter::bytecode_should_reexecute(code) ||
861 (is_anewarray && code == Bytecodes::_multianewarray);
862 // Reexecute _multianewarray bytecode which was replaced with
863 // sequence of [a]newarray. See Parse::do_multianewarray().
864 //
865 // Note: interpreter should not have it set since this optimization
866 // is limited by dimensions and guarded by flag so in some cases
867 // multianewarray() runtime calls will be generated and
868 // the bytecode should not be reexecutes (stack will not be reset).
869 } else {
870 return false;
871 }
872 }
873
874 // Helper function for adding JVMState and debug information to node
875 void GraphKit::add_safepoint_edges(SafePointNode* call, bool must_throw) {
876 // Add the safepoint edges to the call (or other safepoint).
877
878 // Make sure dead locals are set to top. This
879 // should help register allocation time and cut down on the size
880 // of the deoptimization information.
881 assert(dead_locals_are_killed(), "garbage in debug info before safepoint");
882
883 // Walk the inline list to fill in the correct set of JVMState's
884 // Also fill in the associated edges for each JVMState.
885
886 // If the bytecode needs to be reexecuted we need to put
887 // the arguments back on the stack.
888 const bool should_reexecute = jvms()->should_reexecute();
889 JVMState* youngest_jvms = should_reexecute ? sync_jvms_for_reexecute() : sync_jvms();
890
891 // NOTE: set_bci (called from sync_jvms) might reset the reexecute bit to
892 // undefined if the bci is different. This is normal for Parse but it
893 // should not happen for LibraryCallKit because only one bci is processed.
894 assert(!is_LibraryCallKit() || (jvms()->should_reexecute() == should_reexecute),
895 "in LibraryCallKit the reexecute bit should not change");
896
897 // If we are guaranteed to throw, we can prune everything but the
898 // input to the current bytecode.
899 bool can_prune_locals = false;
900 uint stack_slots_not_pruned = 0;
901 int inputs = 0, depth = 0;
902 if (must_throw) {
903 assert(method() == youngest_jvms->method(), "sanity");
904 if (compute_stack_effects(inputs, depth)) {
905 can_prune_locals = true;
906 stack_slots_not_pruned = inputs;
907 }
908 }
909
910 if (env()->should_retain_local_variables()) {
911 // At any safepoint, this method can get breakpointed, which would
912 // then require an immediate deoptimization.
913 can_prune_locals = false; // do not prune locals
914 stack_slots_not_pruned = 0;
915 }
916
917 // do not scribble on the input jvms
918 JVMState* out_jvms = youngest_jvms->clone_deep(C);
919 call->set_jvms(out_jvms); // Start jvms list for call node
920
921 // For a known set of bytecodes, the interpreter should reexecute them if
922 // deoptimization happens. We set the reexecute state for them here
923 if (out_jvms->is_reexecute_undefined() && //don't change if already specified
924 should_reexecute_implied_by_bytecode(out_jvms, call->is_AllocateArray())) {
925 #ifdef ASSERT
926 int inputs = 0, not_used; // initialized by GraphKit::compute_stack_effects()
927 assert(method() == youngest_jvms->method(), "sanity");
928 assert(compute_stack_effects(inputs, not_used), "unknown bytecode: %s", Bytecodes::name(java_bc()));
929 assert(out_jvms->sp() >= (uint)inputs, "not enough operands for reexecution");
930 #endif // ASSERT
931 out_jvms->set_should_reexecute(true); //NOTE: youngest_jvms not changed
932 }
933
934 // Presize the call:
935 DEBUG_ONLY(uint non_debug_edges = call->req());
936 call->add_req_batch(top(), youngest_jvms->debug_depth());
937 assert(call->req() == non_debug_edges + youngest_jvms->debug_depth(), "");
938
939 // Set up edges so that the call looks like this:
940 // Call [state:] ctl io mem fptr retadr
941 // [parms:] parm0 ... parmN
942 // [root:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
943 // [...mid:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN [...]
944 // [young:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
945 // Note that caller debug info precedes callee debug info.
946
947 // Fill pointer walks backwards from "young:" to "root:" in the diagram above:
948 uint debug_ptr = call->req();
949
950 // Loop over the map input edges associated with jvms, add them
951 // to the call node, & reset all offsets to match call node array.
952 for (JVMState* in_jvms = youngest_jvms; in_jvms != nullptr; ) {
953 uint debug_end = debug_ptr;
954 uint debug_start = debug_ptr - in_jvms->debug_size();
955 debug_ptr = debug_start; // back up the ptr
956
957 uint p = debug_start; // walks forward in [debug_start, debug_end)
958 uint j, k, l;
959 SafePointNode* in_map = in_jvms->map();
960 out_jvms->set_map(call);
961
962 if (can_prune_locals) {
963 assert(in_jvms->method() == out_jvms->method(), "sanity");
964 // If the current throw can reach an exception handler in this JVMS,
965 // then we must keep everything live that can reach that handler.
966 // As a quick and dirty approximation, we look for any handlers at all.
967 if (in_jvms->method()->has_exception_handlers()) {
968 can_prune_locals = false;
969 }
970 }
971
972 // Add the Locals
973 k = in_jvms->locoff();
974 l = in_jvms->loc_size();
975 out_jvms->set_locoff(p);
976 if (!can_prune_locals) {
977 for (j = 0; j < l; j++)
978 call->set_req(p++, in_map->in(k+j));
979 } else {
980 p += l; // already set to top above by add_req_batch
981 }
982
983 // Add the Expression Stack
984 k = in_jvms->stkoff();
985 l = in_jvms->sp();
986 out_jvms->set_stkoff(p);
987 if (!can_prune_locals) {
988 for (j = 0; j < l; j++)
989 call->set_req(p++, in_map->in(k+j));
990 } else if (can_prune_locals && stack_slots_not_pruned != 0) {
991 // Divide stack into {S0,...,S1}, where S0 is set to top.
992 uint s1 = stack_slots_not_pruned;
993 stack_slots_not_pruned = 0; // for next iteration
994 if (s1 > l) s1 = l;
995 uint s0 = l - s1;
996 p += s0; // skip the tops preinstalled by add_req_batch
997 for (j = s0; j < l; j++)
998 call->set_req(p++, in_map->in(k+j));
999 } else {
1000 p += l; // already set to top above by add_req_batch
1001 }
1002
1003 // Add the Monitors
1004 k = in_jvms->monoff();
1005 l = in_jvms->mon_size();
1006 out_jvms->set_monoff(p);
1007 for (j = 0; j < l; j++)
1008 call->set_req(p++, in_map->in(k+j));
1009
1010 // Copy any scalar object fields.
1011 k = in_jvms->scloff();
1012 l = in_jvms->scl_size();
1013 out_jvms->set_scloff(p);
1014 for (j = 0; j < l; j++)
1015 call->set_req(p++, in_map->in(k+j));
1016
1017 // Finish the new jvms.
1018 out_jvms->set_endoff(p);
1019
1020 assert(out_jvms->endoff() == debug_end, "fill ptr must match");
1021 assert(out_jvms->depth() == in_jvms->depth(), "depth must match");
1022 assert(out_jvms->loc_size() == in_jvms->loc_size(), "size must match");
1023 assert(out_jvms->mon_size() == in_jvms->mon_size(), "size must match");
1024 assert(out_jvms->scl_size() == in_jvms->scl_size(), "size must match");
1025 assert(out_jvms->debug_size() == in_jvms->debug_size(), "size must match");
1026
1027 // Update the two tail pointers in parallel.
1028 out_jvms = out_jvms->caller();
1029 in_jvms = in_jvms->caller();
1030 }
1031
1032 assert(debug_ptr == non_debug_edges, "debug info must fit exactly");
1033
1034 // Test the correctness of JVMState::debug_xxx accessors:
1035 assert(call->jvms()->debug_start() == non_debug_edges, "");
1036 assert(call->jvms()->debug_end() == call->req(), "");
1037 assert(call->jvms()->debug_depth() == call->req() - non_debug_edges, "");
1038 }
1039
1040 bool GraphKit::compute_stack_effects(int& inputs, int& depth) {
1041 Bytecodes::Code code = java_bc();
1042 if (code == Bytecodes::_wide) {
1043 code = method()->java_code_at_bci(bci() + 1);
1044 }
1045
1046 if (code != Bytecodes::_illegal) {
1047 depth = Bytecodes::depth(code); // checkcast=0, athrow=-1
1048 }
1049
1050 auto rsize = [&]() {
1051 assert(code != Bytecodes::_illegal, "code is illegal!");
1052 BasicType rtype = Bytecodes::result_type(code); // checkcast=P, athrow=V
1053 return (rtype < T_CONFLICT) ? type2size[rtype] : 0;
1054 };
1055
1056 switch (code) {
1057 case Bytecodes::_illegal:
1058 return false;
1059
1060 case Bytecodes::_ldc:
1061 case Bytecodes::_ldc_w:
1062 case Bytecodes::_ldc2_w:
1063 inputs = 0;
1064 break;
1065
1066 case Bytecodes::_dup: inputs = 1; break;
1067 case Bytecodes::_dup_x1: inputs = 2; break;
1068 case Bytecodes::_dup_x2: inputs = 3; break;
1069 case Bytecodes::_dup2: inputs = 2; break;
1070 case Bytecodes::_dup2_x1: inputs = 3; break;
1071 case Bytecodes::_dup2_x2: inputs = 4; break;
1072 case Bytecodes::_swap: inputs = 2; break;
1073 case Bytecodes::_arraylength: inputs = 1; break;
1074
1075 case Bytecodes::_getstatic:
1076 case Bytecodes::_putstatic:
1077 case Bytecodes::_getfield:
1078 case Bytecodes::_putfield:
1079 {
1080 bool ignored_will_link;
1081 ciField* field = method()->get_field_at_bci(bci(), ignored_will_link);
1082 int size = field->type()->size();
1083 bool is_get = (depth >= 0), is_static = (depth & 1);
1084 inputs = (is_static ? 0 : 1);
1085 if (is_get) {
1086 depth = size - inputs;
1087 } else {
1088 inputs += size; // putxxx pops the value from the stack
1089 depth = - inputs;
1090 }
1091 }
1092 break;
1093
1094 case Bytecodes::_invokevirtual:
1095 case Bytecodes::_invokespecial:
1096 case Bytecodes::_invokestatic:
1097 case Bytecodes::_invokedynamic:
1098 case Bytecodes::_invokeinterface:
1099 {
1100 bool ignored_will_link;
1101 ciSignature* declared_signature = nullptr;
1102 ciMethod* ignored_callee = method()->get_method_at_bci(bci(), ignored_will_link, &declared_signature);
1103 assert(declared_signature != nullptr, "cannot be null");
1104 inputs = declared_signature->arg_size_for_bc(code);
1105 int size = declared_signature->return_type()->size();
1106 depth = size - inputs;
1107 }
1108 break;
1109
1110 case Bytecodes::_multianewarray:
1111 {
1112 ciBytecodeStream iter(method());
1113 iter.reset_to_bci(bci());
1114 iter.next();
1115 inputs = iter.get_dimensions();
1116 assert(rsize() == 1, "");
1117 depth = 1 - inputs;
1118 }
1119 break;
1120
1121 case Bytecodes::_ireturn:
1122 case Bytecodes::_lreturn:
1123 case Bytecodes::_freturn:
1124 case Bytecodes::_dreturn:
1125 case Bytecodes::_areturn:
1126 assert(rsize() == -depth, "");
1127 inputs = -depth;
1128 break;
1129
1130 case Bytecodes::_jsr:
1131 case Bytecodes::_jsr_w:
1132 inputs = 0;
1133 depth = 1; // S.B. depth=1, not zero
1134 break;
1135
1136 default:
1137 // bytecode produces a typed result
1138 inputs = rsize() - depth;
1139 assert(inputs >= 0, "");
1140 break;
1141 }
1142
1143 #ifdef ASSERT
1144 // spot check
1145 int outputs = depth + inputs;
1146 assert(outputs >= 0, "sanity");
1147 switch (code) {
1148 case Bytecodes::_checkcast: assert(inputs == 1 && outputs == 1, ""); break;
1149 case Bytecodes::_athrow: assert(inputs == 1 && outputs == 0, ""); break;
1150 case Bytecodes::_aload_0: assert(inputs == 0 && outputs == 1, ""); break;
1151 case Bytecodes::_return: assert(inputs == 0 && outputs == 0, ""); break;
1152 case Bytecodes::_drem: assert(inputs == 4 && outputs == 2, ""); break;
1153 default: break;
1154 }
1155 #endif //ASSERT
1156
1157 return true;
1158 }
1159
1160
1161
1162 //------------------------------basic_plus_adr---------------------------------
1163 Node* GraphKit::basic_plus_adr(Node* base, Node* ptr, Node* offset) {
1164 // short-circuit a common case
1165 if (offset == intcon(0)) return ptr;
1166 return _gvn.transform( new AddPNode(base, ptr, offset) );
1167 }
1168
1169 Node* GraphKit::ConvI2L(Node* offset) {
1170 // short-circuit a common case
1171 jint offset_con = find_int_con(offset, Type::OffsetBot);
1172 if (offset_con != Type::OffsetBot) {
1173 return longcon((jlong) offset_con);
1174 }
1175 return _gvn.transform( new ConvI2LNode(offset));
1176 }
1177
1178 Node* GraphKit::ConvI2UL(Node* offset) {
1179 juint offset_con = (juint) find_int_con(offset, Type::OffsetBot);
1180 if (offset_con != (juint) Type::OffsetBot) {
1181 return longcon((julong) offset_con);
1182 }
1183 Node* conv = _gvn.transform( new ConvI2LNode(offset));
1184 Node* mask = _gvn.transform(ConLNode::make((julong) max_juint));
1185 return _gvn.transform( new AndLNode(conv, mask) );
1186 }
1187
1188 Node* GraphKit::ConvL2I(Node* offset) {
1189 // short-circuit a common case
1190 jlong offset_con = find_long_con(offset, (jlong)Type::OffsetBot);
1191 if (offset_con != (jlong)Type::OffsetBot) {
1192 return intcon((int) offset_con);
1193 }
1194 return _gvn.transform( new ConvL2INode(offset));
1195 }
1196
1197 //-------------------------load_object_klass-----------------------------------
1198 Node* GraphKit::load_object_klass(Node* obj) {
1199 // Special-case a fresh allocation to avoid building nodes:
1200 Node* akls = AllocateNode::Ideal_klass(obj, &_gvn);
1201 if (akls != nullptr) return akls;
1202 Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes());
1203 return _gvn.transform(LoadKlassNode::make(_gvn, immutable_memory(), k_adr, TypeInstPtr::KLASS));
1204 }
1205
1206 //-------------------------load_array_length-----------------------------------
1207 Node* GraphKit::load_array_length(Node* array) {
1208 // Special-case a fresh allocation to avoid building nodes:
1209 AllocateArrayNode* alloc = AllocateArrayNode::Ideal_array_allocation(array);
1210 Node *alen;
1211 if (alloc == nullptr) {
1212 Node *r_adr = basic_plus_adr(array, arrayOopDesc::length_offset_in_bytes());
1213 alen = _gvn.transform( new LoadRangeNode(nullptr, immutable_memory(), r_adr, TypeInt::POS));
1214 } else {
1215 alen = array_ideal_length(alloc, _gvn.type(array)->is_oopptr(), false);
1216 }
1217 return alen;
1218 }
1219
1220 Node* GraphKit::array_ideal_length(AllocateArrayNode* alloc,
1221 const TypeOopPtr* oop_type,
1222 bool replace_length_in_map) {
1223 Node* length = alloc->Ideal_length();
1224 if (replace_length_in_map == false || map()->find_edge(length) >= 0) {
1225 Node* ccast = alloc->make_ideal_length(oop_type, &_gvn);
1226 if (ccast != length) {
1227 // do not transform ccast here, it might convert to top node for
1228 // negative array length and break assumptions in parsing stage.
1229 _gvn.set_type_bottom(ccast);
1230 record_for_igvn(ccast);
1231 if (replace_length_in_map) {
1232 replace_in_map(length, ccast);
1233 }
1234 return ccast;
1235 }
1236 }
1237 return length;
1238 }
1239
1240 //------------------------------do_null_check----------------------------------
1241 // Helper function to do a null pointer check. Returned value is
1242 // the incoming address with null casted away. You are allowed to use the
1243 // not-null value only if you are control dependent on the test.
1244 #ifndef PRODUCT
1245 extern uint explicit_null_checks_inserted,
1246 explicit_null_checks_elided;
1247 #endif
1248 Node* GraphKit::null_check_common(Node* value, BasicType type,
1249 // optional arguments for variations:
1250 bool assert_null,
1251 Node* *null_control,
1252 bool speculative) {
1253 assert(!assert_null || null_control == nullptr, "not both at once");
1254 if (stopped()) return top();
1255 NOT_PRODUCT(explicit_null_checks_inserted++);
1256
1257 // Construct null check
1258 Node *chk = nullptr;
1259 switch(type) {
1260 case T_LONG : chk = new CmpLNode(value, _gvn.zerocon(T_LONG)); break;
1261 case T_INT : chk = new CmpINode(value, _gvn.intcon(0)); break;
1262 case T_ARRAY : // fall through
1263 type = T_OBJECT; // simplify further tests
1264 case T_OBJECT : {
1265 const Type *t = _gvn.type( value );
1266
1267 const TypeOopPtr* tp = t->isa_oopptr();
1268 if (tp != nullptr && !tp->is_loaded()
1269 // Only for do_null_check, not any of its siblings:
1270 && !assert_null && null_control == nullptr) {
1271 // Usually, any field access or invocation on an unloaded oop type
1272 // will simply fail to link, since the statically linked class is
1273 // likely also to be unloaded. However, in -Xcomp mode, sometimes
1274 // the static class is loaded but the sharper oop type is not.
1275 // Rather than checking for this obscure case in lots of places,
1276 // we simply observe that a null check on an unloaded class
1277 // will always be followed by a nonsense operation, so we
1278 // can just issue the uncommon trap here.
1279 // Our access to the unloaded class will only be correct
1280 // after it has been loaded and initialized, which requires
1281 // a trip through the interpreter.
1282 ciKlass* klass = tp->unloaded_klass();
1283 #ifndef PRODUCT
1284 if (WizardMode) { tty->print("Null check of unloaded "); klass->print(); tty->cr(); }
1285 #endif
1286 uncommon_trap(Deoptimization::Reason_unloaded,
1287 Deoptimization::Action_reinterpret,
1288 klass, "!loaded");
1289 return top();
1290 }
1291
1292 if (assert_null) {
1293 // See if the type is contained in NULL_PTR.
1294 // If so, then the value is already null.
1295 if (t->higher_equal(TypePtr::NULL_PTR)) {
1296 NOT_PRODUCT(explicit_null_checks_elided++);
1297 return value; // Elided null assert quickly!
1298 }
1299 } else {
1300 // See if mixing in the null pointer changes type.
1301 // If so, then the null pointer was not allowed in the original
1302 // type. In other words, "value" was not-null.
1303 if (t->meet(TypePtr::NULL_PTR) != t->remove_speculative()) {
1304 // same as: if (!TypePtr::NULL_PTR->higher_equal(t)) ...
1305 NOT_PRODUCT(explicit_null_checks_elided++);
1306 return value; // Elided null check quickly!
1307 }
1308 }
1309 chk = new CmpPNode( value, null() );
1310 break;
1311 }
1312
1313 default:
1314 fatal("unexpected type: %s", type2name(type));
1315 }
1316 assert(chk != nullptr, "sanity check");
1317 chk = _gvn.transform(chk);
1318
1319 BoolTest::mask btest = assert_null ? BoolTest::eq : BoolTest::ne;
1320 BoolNode *btst = new BoolNode( chk, btest);
1321 Node *tst = _gvn.transform( btst );
1322
1323 //-----------
1324 // if peephole optimizations occurred, a prior test existed.
1325 // If a prior test existed, maybe it dominates as we can avoid this test.
1326 if (tst != btst && type == T_OBJECT) {
1327 // At this point we want to scan up the CFG to see if we can
1328 // find an identical test (and so avoid this test altogether).
1329 Node *cfg = control();
1330 int depth = 0;
1331 while( depth < 16 ) { // Limit search depth for speed
1332 if( cfg->Opcode() == Op_IfTrue &&
1333 cfg->in(0)->in(1) == tst ) {
1334 // Found prior test. Use "cast_not_null" to construct an identical
1335 // CastPP (and hence hash to) as already exists for the prior test.
1336 // Return that casted value.
1337 if (assert_null) {
1338 replace_in_map(value, null());
1339 return null(); // do not issue the redundant test
1340 }
1341 Node *oldcontrol = control();
1342 set_control(cfg);
1343 Node *res = cast_not_null(value);
1344 set_control(oldcontrol);
1345 NOT_PRODUCT(explicit_null_checks_elided++);
1346 return res;
1347 }
1348 cfg = IfNode::up_one_dom(cfg, /*linear_only=*/ true);
1349 if (cfg == nullptr) break; // Quit at region nodes
1350 depth++;
1351 }
1352 }
1353
1354 //-----------
1355 // Branch to failure if null
1356 float ok_prob = PROB_MAX; // a priori estimate: nulls never happen
1357 Deoptimization::DeoptReason reason;
1358 if (assert_null) {
1359 reason = Deoptimization::reason_null_assert(speculative);
1360 } else if (type == T_OBJECT) {
1361 reason = Deoptimization::reason_null_check(speculative);
1362 } else {
1363 reason = Deoptimization::Reason_div0_check;
1364 }
1365 // %%% Since Reason_unhandled is not recorded on a per-bytecode basis,
1366 // ciMethodData::has_trap_at will return a conservative -1 if any
1367 // must-be-null assertion has failed. This could cause performance
1368 // problems for a method after its first do_null_assert failure.
1369 // Consider using 'Reason_class_check' instead?
1370
1371 // To cause an implicit null check, we set the not-null probability
1372 // to the maximum (PROB_MAX). For an explicit check the probability
1373 // is set to a smaller value.
1374 if (null_control != nullptr || too_many_traps(reason)) {
1375 // probability is less likely
1376 ok_prob = PROB_LIKELY_MAG(3);
1377 } else if (!assert_null &&
1378 (ImplicitNullCheckThreshold > 0) &&
1379 method() != nullptr &&
1380 (method()->method_data()->trap_count(reason)
1381 >= (uint)ImplicitNullCheckThreshold)) {
1382 ok_prob = PROB_LIKELY_MAG(3);
1383 }
1384
1385 if (null_control != nullptr) {
1386 IfNode* iff = create_and_map_if(control(), tst, ok_prob, COUNT_UNKNOWN);
1387 Node* null_true = _gvn.transform( new IfFalseNode(iff));
1388 set_control( _gvn.transform( new IfTrueNode(iff)));
1389 #ifndef PRODUCT
1390 if (null_true == top()) {
1391 explicit_null_checks_elided++;
1392 }
1393 #endif
1394 (*null_control) = null_true;
1395 } else {
1396 BuildCutout unless(this, tst, ok_prob);
1397 // Check for optimizer eliding test at parse time
1398 if (stopped()) {
1399 // Failure not possible; do not bother making uncommon trap.
1400 NOT_PRODUCT(explicit_null_checks_elided++);
1401 } else if (assert_null) {
1402 uncommon_trap(reason,
1403 Deoptimization::Action_make_not_entrant,
1404 nullptr, "assert_null");
1405 } else {
1406 replace_in_map(value, zerocon(type));
1407 builtin_throw(reason);
1408 }
1409 }
1410
1411 // Must throw exception, fall-thru not possible?
1412 if (stopped()) {
1413 return top(); // No result
1414 }
1415
1416 if (assert_null) {
1417 // Cast obj to null on this path.
1418 replace_in_map(value, zerocon(type));
1419 return zerocon(type);
1420 }
1421
1422 // Cast obj to not-null on this path, if there is no null_control.
1423 // (If there is a null_control, a non-null value may come back to haunt us.)
1424 if (type == T_OBJECT) {
1425 Node* cast = cast_not_null(value, false);
1426 if (null_control == nullptr || (*null_control) == top())
1427 replace_in_map(value, cast);
1428 value = cast;
1429 }
1430
1431 return value;
1432 }
1433
1434
1435 //------------------------------cast_not_null----------------------------------
1436 // Cast obj to not-null on this path
1437 Node* GraphKit::cast_not_null(Node* obj, bool do_replace_in_map) {
1438 const Type *t = _gvn.type(obj);
1439 const Type *t_not_null = t->join_speculative(TypePtr::NOTNULL);
1440 // Object is already not-null?
1441 if( t == t_not_null ) return obj;
1442
1443 Node* cast = new CastPPNode(control(), obj,t_not_null);
1444 cast = _gvn.transform( cast );
1445
1446 // Scan for instances of 'obj' in the current JVM mapping.
1447 // These instances are known to be not-null after the test.
1448 if (do_replace_in_map)
1449 replace_in_map(obj, cast);
1450
1451 return cast; // Return casted value
1452 }
1453
1454 // Sometimes in intrinsics, we implicitly know an object is not null
1455 // (there's no actual null check) so we can cast it to not null. In
1456 // the course of optimizations, the input to the cast can become null.
1457 // In that case that data path will die and we need the control path
1458 // to become dead as well to keep the graph consistent. So we have to
1459 // add a check for null for which one branch can't be taken. It uses
1460 // an OpaqueNotNull node that will cause the check to be removed after loop
1461 // opts so the test goes away and the compiled code doesn't execute a
1462 // useless check.
1463 Node* GraphKit::must_be_not_null(Node* value, bool do_replace_in_map) {
1464 if (!TypePtr::NULL_PTR->higher_equal(_gvn.type(value))) {
1465 return value;
1466 }
1467 Node* chk = _gvn.transform(new CmpPNode(value, null()));
1468 Node* tst = _gvn.transform(new BoolNode(chk, BoolTest::ne));
1469 Node* opaq = _gvn.transform(new OpaqueNotNullNode(C, tst));
1470 IfNode* iff = new IfNode(control(), opaq, PROB_MAX, COUNT_UNKNOWN);
1471 _gvn.set_type(iff, iff->Value(&_gvn));
1472 if (!tst->is_Con()) {
1473 record_for_igvn(iff);
1474 }
1475 Node *if_f = _gvn.transform(new IfFalseNode(iff));
1476 Node *frame = _gvn.transform(new ParmNode(C->start(), TypeFunc::FramePtr));
1477 Node* halt = _gvn.transform(new HaltNode(if_f, frame, "unexpected null in intrinsic"));
1478 C->root()->add_req(halt);
1479 Node *if_t = _gvn.transform(new IfTrueNode(iff));
1480 set_control(if_t);
1481 return cast_not_null(value, do_replace_in_map);
1482 }
1483
1484
1485 //--------------------------replace_in_map-------------------------------------
1486 void GraphKit::replace_in_map(Node* old, Node* neww) {
1487 if (old == neww) {
1488 return;
1489 }
1490
1491 map()->replace_edge(old, neww);
1492
1493 // Note: This operation potentially replaces any edge
1494 // on the map. This includes locals, stack, and monitors
1495 // of the current (innermost) JVM state.
1496
1497 // don't let inconsistent types from profiling escape this
1498 // method
1499
1500 const Type* told = _gvn.type(old);
1501 const Type* tnew = _gvn.type(neww);
1502
1503 if (!tnew->higher_equal(told)) {
1504 return;
1505 }
1506
1507 map()->record_replaced_node(old, neww);
1508 }
1509
1510
1511 //=============================================================================
1512 //--------------------------------memory---------------------------------------
1513 Node* GraphKit::memory(uint alias_idx) {
1514 MergeMemNode* mem = merged_memory();
1515 Node* p = mem->memory_at(alias_idx);
1516 assert(p != mem->empty_memory(), "empty");
1517 _gvn.set_type(p, Type::MEMORY); // must be mapped
1518 return p;
1519 }
1520
1521 //-----------------------------reset_memory------------------------------------
1522 Node* GraphKit::reset_memory() {
1523 Node* mem = map()->memory();
1524 // do not use this node for any more parsing!
1525 debug_only( map()->set_memory((Node*)nullptr) );
1526 return _gvn.transform( mem );
1527 }
1528
1529 //------------------------------set_all_memory---------------------------------
1530 void GraphKit::set_all_memory(Node* newmem) {
1531 Node* mergemem = MergeMemNode::make(newmem);
1532 gvn().set_type_bottom(mergemem);
1533 map()->set_memory(mergemem);
1534 }
1535
1536 //------------------------------set_all_memory_call----------------------------
1537 void GraphKit::set_all_memory_call(Node* call, bool separate_io_proj) {
1538 Node* newmem = _gvn.transform( new ProjNode(call, TypeFunc::Memory, separate_io_proj) );
1539 set_all_memory(newmem);
1540 }
1541
1542 //=============================================================================
1543 //
1544 // parser factory methods for MemNodes
1545 //
1546 // These are layered on top of the factory methods in LoadNode and StoreNode,
1547 // and integrate with the parser's memory state and _gvn engine.
1548 //
1549
1550 // factory methods in "int adr_idx"
1551 Node* GraphKit::make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
1552 MemNode::MemOrd mo,
1553 LoadNode::ControlDependency control_dependency,
1554 bool require_atomic_access,
1555 bool unaligned,
1556 bool mismatched,
1557 bool unsafe,
1558 uint8_t barrier_data) {
1559 int adr_idx = C->get_alias_index(_gvn.type(adr)->isa_ptr());
1560 assert(adr_idx != Compile::AliasIdxTop, "use other make_load factory" );
1561 const TypePtr* adr_type = nullptr; // debug-mode-only argument
1562 debug_only(adr_type = C->get_adr_type(adr_idx));
1563 Node* mem = memory(adr_idx);
1564 Node* ld = LoadNode::make(_gvn, ctl, mem, adr, adr_type, t, bt, mo, control_dependency, require_atomic_access, unaligned, mismatched, unsafe, barrier_data);
1565 ld = _gvn.transform(ld);
1566 if (((bt == T_OBJECT) && C->do_escape_analysis()) || C->eliminate_boxing()) {
1567 // Improve graph before escape analysis and boxing elimination.
1568 record_for_igvn(ld);
1569 if (ld->is_DecodeN()) {
1570 // Also record the actual load (LoadN) in case ld is DecodeN. In some
1571 // rare corner cases, ld->in(1) can be something other than LoadN (e.g.,
1572 // a Phi). Recording such cases is still perfectly sound, but may be
1573 // unnecessary and result in some minor IGVN overhead.
1574 record_for_igvn(ld->in(1));
1575 }
1576 }
1577 return ld;
1578 }
1579
1580 Node* GraphKit::store_to_memory(Node* ctl, Node* adr, Node *val, BasicType bt,
1581 MemNode::MemOrd mo,
1582 bool require_atomic_access,
1583 bool unaligned,
1584 bool mismatched,
1585 bool unsafe,
1586 int barrier_data) {
1587 int adr_idx = C->get_alias_index(_gvn.type(adr)->isa_ptr());
1588 assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1589 const TypePtr* adr_type = nullptr;
1590 debug_only(adr_type = C->get_adr_type(adr_idx));
1591 Node *mem = memory(adr_idx);
1592 Node* st = StoreNode::make(_gvn, ctl, mem, adr, adr_type, val, bt, mo, require_atomic_access);
1593 if (unaligned) {
1594 st->as_Store()->set_unaligned_access();
1595 }
1596 if (mismatched) {
1597 st->as_Store()->set_mismatched_access();
1598 }
1599 if (unsafe) {
1600 st->as_Store()->set_unsafe_access();
1601 }
1602 st->as_Store()->set_barrier_data(barrier_data);
1603 st = _gvn.transform(st);
1604 set_memory(st, adr_idx);
1605 // Back-to-back stores can only remove intermediate store with DU info
1606 // so push on worklist for optimizer.
1607 if (mem->req() > MemNode::Address && adr == mem->in(MemNode::Address))
1608 record_for_igvn(st);
1609
1610 return st;
1611 }
1612
1613 Node* GraphKit::access_store_at(Node* obj,
1614 Node* adr,
1615 const TypePtr* adr_type,
1616 Node* val,
1617 const Type* val_type,
1618 BasicType bt,
1619 DecoratorSet decorators) {
1620 // Transformation of a value which could be null pointer (CastPP #null)
1621 // could be delayed during Parse (for example, in adjust_map_after_if()).
1622 // Execute transformation here to avoid barrier generation in such case.
1623 if (_gvn.type(val) == TypePtr::NULL_PTR) {
1624 val = _gvn.makecon(TypePtr::NULL_PTR);
1625 }
1626
1627 if (stopped()) {
1628 return top(); // Dead path ?
1629 }
1630
1631 assert(val != nullptr, "not dead path");
1632
1633 C2AccessValuePtr addr(adr, adr_type);
1634 C2AccessValue value(val, val_type);
1635 C2ParseAccess access(this, decorators | C2_WRITE_ACCESS, bt, obj, addr);
1636 if (access.is_raw()) {
1637 return _barrier_set->BarrierSetC2::store_at(access, value);
1638 } else {
1639 return _barrier_set->store_at(access, value);
1640 }
1641 }
1642
1643 Node* GraphKit::access_load_at(Node* obj, // containing obj
1644 Node* adr, // actual address to store val at
1645 const TypePtr* adr_type,
1646 const Type* val_type,
1647 BasicType bt,
1648 DecoratorSet decorators) {
1649 if (stopped()) {
1650 return top(); // Dead path ?
1651 }
1652
1653 C2AccessValuePtr addr(adr, adr_type);
1654 C2ParseAccess access(this, decorators | C2_READ_ACCESS, bt, obj, addr);
1655 if (access.is_raw()) {
1656 return _barrier_set->BarrierSetC2::load_at(access, val_type);
1657 } else {
1658 return _barrier_set->load_at(access, val_type);
1659 }
1660 }
1661
1662 Node* GraphKit::access_load(Node* adr, // actual address to load val at
1663 const Type* val_type,
1664 BasicType bt,
1665 DecoratorSet decorators) {
1666 if (stopped()) {
1667 return top(); // Dead path ?
1668 }
1669
1670 C2AccessValuePtr addr(adr, adr->bottom_type()->is_ptr());
1671 C2ParseAccess access(this, decorators | C2_READ_ACCESS, bt, nullptr, addr);
1672 if (access.is_raw()) {
1673 return _barrier_set->BarrierSetC2::load_at(access, val_type);
1674 } else {
1675 return _barrier_set->load_at(access, val_type);
1676 }
1677 }
1678
1679 Node* GraphKit::access_atomic_cmpxchg_val_at(Node* obj,
1680 Node* adr,
1681 const TypePtr* adr_type,
1682 int alias_idx,
1683 Node* expected_val,
1684 Node* new_val,
1685 const Type* value_type,
1686 BasicType bt,
1687 DecoratorSet decorators) {
1688 C2AccessValuePtr addr(adr, adr_type);
1689 C2AtomicParseAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS,
1690 bt, obj, addr, alias_idx);
1691 if (access.is_raw()) {
1692 return _barrier_set->BarrierSetC2::atomic_cmpxchg_val_at(access, expected_val, new_val, value_type);
1693 } else {
1694 return _barrier_set->atomic_cmpxchg_val_at(access, expected_val, new_val, value_type);
1695 }
1696 }
1697
1698 Node* GraphKit::access_atomic_cmpxchg_bool_at(Node* obj,
1699 Node* adr,
1700 const TypePtr* adr_type,
1701 int alias_idx,
1702 Node* expected_val,
1703 Node* new_val,
1704 const Type* value_type,
1705 BasicType bt,
1706 DecoratorSet decorators) {
1707 C2AccessValuePtr addr(adr, adr_type);
1708 C2AtomicParseAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS,
1709 bt, obj, addr, alias_idx);
1710 if (access.is_raw()) {
1711 return _barrier_set->BarrierSetC2::atomic_cmpxchg_bool_at(access, expected_val, new_val, value_type);
1712 } else {
1713 return _barrier_set->atomic_cmpxchg_bool_at(access, expected_val, new_val, value_type);
1714 }
1715 }
1716
1717 Node* GraphKit::access_atomic_xchg_at(Node* obj,
1718 Node* adr,
1719 const TypePtr* adr_type,
1720 int alias_idx,
1721 Node* new_val,
1722 const Type* value_type,
1723 BasicType bt,
1724 DecoratorSet decorators) {
1725 C2AccessValuePtr addr(adr, adr_type);
1726 C2AtomicParseAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS,
1727 bt, obj, addr, alias_idx);
1728 if (access.is_raw()) {
1729 return _barrier_set->BarrierSetC2::atomic_xchg_at(access, new_val, value_type);
1730 } else {
1731 return _barrier_set->atomic_xchg_at(access, new_val, value_type);
1732 }
1733 }
1734
1735 Node* GraphKit::access_atomic_add_at(Node* obj,
1736 Node* adr,
1737 const TypePtr* adr_type,
1738 int alias_idx,
1739 Node* new_val,
1740 const Type* value_type,
1741 BasicType bt,
1742 DecoratorSet decorators) {
1743 C2AccessValuePtr addr(adr, adr_type);
1744 C2AtomicParseAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS, bt, obj, addr, alias_idx);
1745 if (access.is_raw()) {
1746 return _barrier_set->BarrierSetC2::atomic_add_at(access, new_val, value_type);
1747 } else {
1748 return _barrier_set->atomic_add_at(access, new_val, value_type);
1749 }
1750 }
1751
1752 void GraphKit::access_clone(Node* src, Node* dst, Node* size, bool is_array) {
1753 return _barrier_set->clone(this, src, dst, size, is_array);
1754 }
1755
1756 //-------------------------array_element_address-------------------------
1757 Node* GraphKit::array_element_address(Node* ary, Node* idx, BasicType elembt,
1758 const TypeInt* sizetype, Node* ctrl) {
1759 uint shift = exact_log2(type2aelembytes(elembt));
1760 uint header = arrayOopDesc::base_offset_in_bytes(elembt);
1761
1762 // short-circuit a common case (saves lots of confusing waste motion)
1763 jint idx_con = find_int_con(idx, -1);
1764 if (idx_con >= 0) {
1765 intptr_t offset = header + ((intptr_t)idx_con << shift);
1766 return basic_plus_adr(ary, offset);
1767 }
1768
1769 // must be correct type for alignment purposes
1770 Node* base = basic_plus_adr(ary, header);
1771 idx = Compile::conv_I2X_index(&_gvn, idx, sizetype, ctrl);
1772 Node* scale = _gvn.transform( new LShiftXNode(idx, intcon(shift)) );
1773 return basic_plus_adr(ary, base, scale);
1774 }
1775
1776 //-------------------------load_array_element-------------------------
1777 Node* GraphKit::load_array_element(Node* ary, Node* idx, const TypeAryPtr* arytype, bool set_ctrl) {
1778 const Type* elemtype = arytype->elem();
1779 BasicType elembt = elemtype->array_element_basic_type();
1780 Node* adr = array_element_address(ary, idx, elembt, arytype->size());
1781 if (elembt == T_NARROWOOP) {
1782 elembt = T_OBJECT; // To satisfy switch in LoadNode::make()
1783 }
1784 Node* ld = access_load_at(ary, adr, arytype, elemtype, elembt,
1785 IN_HEAP | IS_ARRAY | (set_ctrl ? C2_CONTROL_DEPENDENT_LOAD : 0));
1786 return ld;
1787 }
1788
1789 //-------------------------set_arguments_for_java_call-------------------------
1790 // Arguments (pre-popped from the stack) are taken from the JVMS.
1791 void GraphKit::set_arguments_for_java_call(CallJavaNode* call) {
1792 // Add the call arguments:
1793 uint nargs = call->method()->arg_size();
1794 for (uint i = 0; i < nargs; i++) {
1795 Node* arg = argument(i);
1796 call->init_req(i + TypeFunc::Parms, arg);
1797 }
1798 }
1799
1800 //---------------------------set_edges_for_java_call---------------------------
1801 // Connect a newly created call into the current JVMS.
1802 // A return value node (if any) is returned from set_edges_for_java_call.
1803 void GraphKit::set_edges_for_java_call(CallJavaNode* call, bool must_throw, bool separate_io_proj) {
1804
1805 // Add the predefined inputs:
1806 call->init_req( TypeFunc::Control, control() );
1807 call->init_req( TypeFunc::I_O , i_o() );
1808 call->init_req( TypeFunc::Memory , reset_memory() );
1809 call->init_req( TypeFunc::FramePtr, frameptr() );
1810 call->init_req( TypeFunc::ReturnAdr, top() );
1811
1812 add_safepoint_edges(call, must_throw);
1813
1814 Node* xcall = _gvn.transform(call);
1815
1816 if (xcall == top()) {
1817 set_control(top());
1818 return;
1819 }
1820 assert(xcall == call, "call identity is stable");
1821
1822 // Re-use the current map to produce the result.
1823
1824 set_control(_gvn.transform(new ProjNode(call, TypeFunc::Control)));
1825 set_i_o( _gvn.transform(new ProjNode(call, TypeFunc::I_O , separate_io_proj)));
1826 set_all_memory_call(xcall, separate_io_proj);
1827
1828 //return xcall; // no need, caller already has it
1829 }
1830
1831 Node* GraphKit::set_results_for_java_call(CallJavaNode* call, bool separate_io_proj, bool deoptimize) {
1832 if (stopped()) return top(); // maybe the call folded up?
1833
1834 // Capture the return value, if any.
1835 Node* ret;
1836 if (call->method() == nullptr ||
1837 call->method()->return_type()->basic_type() == T_VOID)
1838 ret = top();
1839 else ret = _gvn.transform(new ProjNode(call, TypeFunc::Parms));
1840
1841 // Note: Since any out-of-line call can produce an exception,
1842 // we always insert an I_O projection from the call into the result.
1843
1844 make_slow_call_ex(call, env()->Throwable_klass(), separate_io_proj, deoptimize);
1845
1846 if (separate_io_proj) {
1847 // The caller requested separate projections be used by the fall
1848 // through and exceptional paths, so replace the projections for
1849 // the fall through path.
1850 set_i_o(_gvn.transform( new ProjNode(call, TypeFunc::I_O) ));
1851 set_all_memory(_gvn.transform( new ProjNode(call, TypeFunc::Memory) ));
1852 }
1853 return ret;
1854 }
1855
1856 //--------------------set_predefined_input_for_runtime_call--------------------
1857 // Reading and setting the memory state is way conservative here.
1858 // The real problem is that I am not doing real Type analysis on memory,
1859 // so I cannot distinguish card mark stores from other stores. Across a GC
1860 // point the Store Barrier and the card mark memory has to agree. I cannot
1861 // have a card mark store and its barrier split across the GC point from
1862 // either above or below. Here I get that to happen by reading ALL of memory.
1863 // A better answer would be to separate out card marks from other memory.
1864 // For now, return the input memory state, so that it can be reused
1865 // after the call, if this call has restricted memory effects.
1866 Node* GraphKit::set_predefined_input_for_runtime_call(SafePointNode* call, Node* narrow_mem) {
1867 // Set fixed predefined input arguments
1868 Node* memory = reset_memory();
1869 Node* m = narrow_mem == nullptr ? memory : narrow_mem;
1870 call->init_req( TypeFunc::Control, control() );
1871 call->init_req( TypeFunc::I_O, top() ); // does no i/o
1872 call->init_req( TypeFunc::Memory, m ); // may gc ptrs
1873 call->init_req( TypeFunc::FramePtr, frameptr() );
1874 call->init_req( TypeFunc::ReturnAdr, top() );
1875 return memory;
1876 }
1877
1878 //-------------------set_predefined_output_for_runtime_call--------------------
1879 // Set control and memory (not i_o) from the call.
1880 // If keep_mem is not null, use it for the output state,
1881 // except for the RawPtr output of the call, if hook_mem is TypeRawPtr::BOTTOM.
1882 // If hook_mem is null, this call produces no memory effects at all.
1883 // If hook_mem is a Java-visible memory slice (such as arraycopy operands),
1884 // then only that memory slice is taken from the call.
1885 // In the last case, we must put an appropriate memory barrier before
1886 // the call, so as to create the correct anti-dependencies on loads
1887 // preceding the call.
1888 void GraphKit::set_predefined_output_for_runtime_call(Node* call,
1889 Node* keep_mem,
1890 const TypePtr* hook_mem) {
1891 // no i/o
1892 set_control(_gvn.transform( new ProjNode(call,TypeFunc::Control) ));
1893 if (keep_mem) {
1894 // First clone the existing memory state
1895 set_all_memory(keep_mem);
1896 if (hook_mem != nullptr) {
1897 // Make memory for the call
1898 Node* mem = _gvn.transform( new ProjNode(call, TypeFunc::Memory) );
1899 // Set the RawPtr memory state only. This covers all the heap top/GC stuff
1900 // We also use hook_mem to extract specific effects from arraycopy stubs.
1901 set_memory(mem, hook_mem);
1902 }
1903 // ...else the call has NO memory effects.
1904
1905 // Make sure the call advertises its memory effects precisely.
1906 // This lets us build accurate anti-dependences in gcm.cpp.
1907 assert(C->alias_type(call->adr_type()) == C->alias_type(hook_mem),
1908 "call node must be constructed correctly");
1909 } else {
1910 assert(hook_mem == nullptr, "");
1911 // This is not a "slow path" call; all memory comes from the call.
1912 set_all_memory_call(call);
1913 }
1914 }
1915
1916 // Keep track of MergeMems feeding into other MergeMems
1917 static void add_mergemem_users_to_worklist(Unique_Node_List& wl, Node* mem) {
1918 if (!mem->is_MergeMem()) {
1919 return;
1920 }
1921 for (SimpleDUIterator i(mem); i.has_next(); i.next()) {
1922 Node* use = i.get();
1923 if (use->is_MergeMem()) {
1924 wl.push(use);
1925 }
1926 }
1927 }
1928
1929 // Replace the call with the current state of the kit.
1930 void GraphKit::replace_call(CallNode* call, Node* result, bool do_replaced_nodes, bool do_asserts) {
1931 JVMState* ejvms = nullptr;
1932 if (has_exceptions()) {
1933 ejvms = transfer_exceptions_into_jvms();
1934 }
1935
1936 ReplacedNodes replaced_nodes = map()->replaced_nodes();
1937 ReplacedNodes replaced_nodes_exception;
1938 Node* ex_ctl = top();
1939
1940 SafePointNode* final_state = stop();
1941
1942 // Find all the needed outputs of this call
1943 CallProjections callprojs;
1944 call->extract_projections(&callprojs, true, do_asserts);
1945
1946 Unique_Node_List wl;
1947 Node* init_mem = call->in(TypeFunc::Memory);
1948 Node* final_mem = final_state->in(TypeFunc::Memory);
1949 Node* final_ctl = final_state->in(TypeFunc::Control);
1950 Node* final_io = final_state->in(TypeFunc::I_O);
1951
1952 // Replace all the old call edges with the edges from the inlining result
1953 if (callprojs.fallthrough_catchproj != nullptr) {
1954 C->gvn_replace_by(callprojs.fallthrough_catchproj, final_ctl);
1955 }
1956 if (callprojs.fallthrough_memproj != nullptr) {
1957 if (final_mem->is_MergeMem()) {
1958 // Parser's exits MergeMem was not transformed but may be optimized
1959 final_mem = _gvn.transform(final_mem);
1960 }
1961 C->gvn_replace_by(callprojs.fallthrough_memproj, final_mem);
1962 add_mergemem_users_to_worklist(wl, final_mem);
1963 }
1964 if (callprojs.fallthrough_ioproj != nullptr) {
1965 C->gvn_replace_by(callprojs.fallthrough_ioproj, final_io);
1966 }
1967
1968 // Replace the result with the new result if it exists and is used
1969 if (callprojs.resproj != nullptr && result != nullptr) {
1970 C->gvn_replace_by(callprojs.resproj, result);
1971 }
1972
1973 if (ejvms == nullptr) {
1974 // No exception edges to simply kill off those paths
1975 if (callprojs.catchall_catchproj != nullptr) {
1976 C->gvn_replace_by(callprojs.catchall_catchproj, C->top());
1977 }
1978 if (callprojs.catchall_memproj != nullptr) {
1979 C->gvn_replace_by(callprojs.catchall_memproj, C->top());
1980 }
1981 if (callprojs.catchall_ioproj != nullptr) {
1982 C->gvn_replace_by(callprojs.catchall_ioproj, C->top());
1983 }
1984 // Replace the old exception object with top
1985 if (callprojs.exobj != nullptr) {
1986 C->gvn_replace_by(callprojs.exobj, C->top());
1987 }
1988 } else {
1989 GraphKit ekit(ejvms);
1990
1991 // Load my combined exception state into the kit, with all phis transformed:
1992 SafePointNode* ex_map = ekit.combine_and_pop_all_exception_states();
1993 replaced_nodes_exception = ex_map->replaced_nodes();
1994
1995 Node* ex_oop = ekit.use_exception_state(ex_map);
1996
1997 if (callprojs.catchall_catchproj != nullptr) {
1998 C->gvn_replace_by(callprojs.catchall_catchproj, ekit.control());
1999 ex_ctl = ekit.control();
2000 }
2001 if (callprojs.catchall_memproj != nullptr) {
2002 Node* ex_mem = ekit.reset_memory();
2003 C->gvn_replace_by(callprojs.catchall_memproj, ex_mem);
2004 add_mergemem_users_to_worklist(wl, ex_mem);
2005 }
2006 if (callprojs.catchall_ioproj != nullptr) {
2007 C->gvn_replace_by(callprojs.catchall_ioproj, ekit.i_o());
2008 }
2009
2010 // Replace the old exception object with the newly created one
2011 if (callprojs.exobj != nullptr) {
2012 C->gvn_replace_by(callprojs.exobj, ex_oop);
2013 }
2014 }
2015
2016 // Disconnect the call from the graph
2017 call->disconnect_inputs(C);
2018 C->gvn_replace_by(call, C->top());
2019
2020 // Clean up any MergeMems that feed other MergeMems since the
2021 // optimizer doesn't like that.
2022 while (wl.size() > 0) {
2023 _gvn.transform(wl.pop());
2024 }
2025
2026 if (callprojs.fallthrough_catchproj != nullptr && !final_ctl->is_top() && do_replaced_nodes) {
2027 replaced_nodes.apply(C, final_ctl);
2028 }
2029 if (!ex_ctl->is_top() && do_replaced_nodes) {
2030 replaced_nodes_exception.apply(C, ex_ctl);
2031 }
2032 }
2033
2034
2035 //------------------------------increment_counter------------------------------
2036 // for statistics: increment a VM counter by 1
2037
2038 void GraphKit::increment_counter(address counter_addr) {
2039 Node* adr1 = makecon(TypeRawPtr::make(counter_addr));
2040 increment_counter(adr1);
2041 }
2042
2043 void GraphKit::increment_counter(Node* counter_addr) {
2044 Node* ctrl = control();
2045 Node* cnt = make_load(ctrl, counter_addr, TypeLong::LONG, T_LONG, MemNode::unordered);
2046 Node* incr = _gvn.transform(new AddLNode(cnt, _gvn.longcon(1)));
2047 store_to_memory(ctrl, counter_addr, incr, T_LONG, MemNode::unordered);
2048 }
2049
2050
2051 //------------------------------uncommon_trap----------------------------------
2052 // Bail out to the interpreter in mid-method. Implemented by calling the
2053 // uncommon_trap blob. This helper function inserts a runtime call with the
2054 // right debug info.
2055 Node* GraphKit::uncommon_trap(int trap_request,
2056 ciKlass* klass, const char* comment,
2057 bool must_throw,
2058 bool keep_exact_action) {
2059 if (failing_internal()) {
2060 stop();
2061 }
2062 if (stopped()) return nullptr; // trap reachable?
2063
2064 // Note: If ProfileTraps is true, and if a deopt. actually
2065 // occurs here, the runtime will make sure an MDO exists. There is
2066 // no need to call method()->ensure_method_data() at this point.
2067
2068 // Set the stack pointer to the right value for reexecution:
2069 set_sp(reexecute_sp());
2070
2071 #ifdef ASSERT
2072 if (!must_throw) {
2073 // Make sure the stack has at least enough depth to execute
2074 // the current bytecode.
2075 int inputs, ignored_depth;
2076 if (compute_stack_effects(inputs, ignored_depth)) {
2077 assert(sp() >= inputs, "must have enough JVMS stack to execute %s: sp=%d, inputs=%d",
2078 Bytecodes::name(java_bc()), sp(), inputs);
2079 }
2080 }
2081 #endif
2082
2083 Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
2084 Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
2085
2086 switch (action) {
2087 case Deoptimization::Action_maybe_recompile:
2088 case Deoptimization::Action_reinterpret:
2089 // Temporary fix for 6529811 to allow virtual calls to be sure they
2090 // get the chance to go from mono->bi->mega
2091 if (!keep_exact_action &&
2092 Deoptimization::trap_request_index(trap_request) < 0 &&
2093 too_many_recompiles(reason)) {
2094 // This BCI is causing too many recompilations.
2095 if (C->log() != nullptr) {
2096 C->log()->elem("observe that='trap_action_change' reason='%s' from='%s' to='none'",
2097 Deoptimization::trap_reason_name(reason),
2098 Deoptimization::trap_action_name(action));
2099 }
2100 action = Deoptimization::Action_none;
2101 trap_request = Deoptimization::make_trap_request(reason, action);
2102 } else {
2103 C->set_trap_can_recompile(true);
2104 }
2105 break;
2106 case Deoptimization::Action_make_not_entrant:
2107 C->set_trap_can_recompile(true);
2108 break;
2109 case Deoptimization::Action_none:
2110 case Deoptimization::Action_make_not_compilable:
2111 break;
2112 default:
2113 #ifdef ASSERT
2114 fatal("unknown action %d: %s", action, Deoptimization::trap_action_name(action));
2115 #endif
2116 break;
2117 }
2118
2119 if (TraceOptoParse) {
2120 char buf[100];
2121 tty->print_cr("Uncommon trap %s at bci:%d",
2122 Deoptimization::format_trap_request(buf, sizeof(buf),
2123 trap_request), bci());
2124 }
2125
2126 CompileLog* log = C->log();
2127 if (log != nullptr) {
2128 int kid = (klass == nullptr)? -1: log->identify(klass);
2129 log->begin_elem("uncommon_trap bci='%d'", bci());
2130 char buf[100];
2131 log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf),
2132 trap_request));
2133 if (kid >= 0) log->print(" klass='%d'", kid);
2134 if (comment != nullptr) log->print(" comment='%s'", comment);
2135 log->end_elem();
2136 }
2137
2138 // Make sure any guarding test views this path as very unlikely
2139 Node *i0 = control()->in(0);
2140 if (i0 != nullptr && i0->is_If()) { // Found a guarding if test?
2141 IfNode *iff = i0->as_If();
2142 float f = iff->_prob; // Get prob
2143 if (control()->Opcode() == Op_IfTrue) {
2144 if (f > PROB_UNLIKELY_MAG(4))
2145 iff->_prob = PROB_MIN;
2146 } else {
2147 if (f < PROB_LIKELY_MAG(4))
2148 iff->_prob = PROB_MAX;
2149 }
2150 }
2151
2152 // Clear out dead values from the debug info.
2153 kill_dead_locals();
2154
2155 // Now insert the uncommon trap subroutine call
2156 address call_addr = OptoRuntime::uncommon_trap_blob()->entry_point();
2157 const TypePtr* no_memory_effects = nullptr;
2158 // Pass the index of the class to be loaded
2159 Node* call = make_runtime_call(RC_NO_LEAF | RC_UNCOMMON |
2160 (must_throw ? RC_MUST_THROW : 0),
2161 OptoRuntime::uncommon_trap_Type(),
2162 call_addr, "uncommon_trap", no_memory_effects,
2163 intcon(trap_request));
2164 assert(call->as_CallStaticJava()->uncommon_trap_request() == trap_request,
2165 "must extract request correctly from the graph");
2166 assert(trap_request != 0, "zero value reserved by uncommon_trap_request");
2167
2168 call->set_req(TypeFunc::ReturnAdr, returnadr());
2169 // The debug info is the only real input to this call.
2170
2171 // Halt-and-catch fire here. The above call should never return!
2172 HaltNode* halt = new HaltNode(control(), frameptr(), "uncommon trap returned which should never happen"
2173 PRODUCT_ONLY(COMMA /*reachable*/false));
2174 _gvn.set_type_bottom(halt);
2175 root()->add_req(halt);
2176
2177 stop_and_kill_map();
2178 return call;
2179 }
2180
2181
2182 //--------------------------just_allocated_object------------------------------
2183 // Report the object that was just allocated.
2184 // It must be the case that there are no intervening safepoints.
2185 // We use this to determine if an object is so "fresh" that
2186 // it does not require card marks.
2187 Node* GraphKit::just_allocated_object(Node* current_control) {
2188 Node* ctrl = current_control;
2189 // Object::<init> is invoked after allocation, most of invoke nodes
2190 // will be reduced, but a region node is kept in parse time, we check
2191 // the pattern and skip the region node if it degraded to a copy.
2192 if (ctrl != nullptr && ctrl->is_Region() && ctrl->req() == 2 &&
2193 ctrl->as_Region()->is_copy()) {
2194 ctrl = ctrl->as_Region()->is_copy();
2195 }
2196 if (C->recent_alloc_ctl() == ctrl) {
2197 return C->recent_alloc_obj();
2198 }
2199 return nullptr;
2200 }
2201
2202
2203 /**
2204 * Record profiling data exact_kls for Node n with the type system so
2205 * that it can propagate it (speculation)
2206 *
2207 * @param n node that the type applies to
2208 * @param exact_kls type from profiling
2209 * @param maybe_null did profiling see null?
2210 *
2211 * @return node with improved type
2212 */
2213 Node* GraphKit::record_profile_for_speculation(Node* n, ciKlass* exact_kls, ProfilePtrKind ptr_kind) {
2214 const Type* current_type = _gvn.type(n);
2215 assert(UseTypeSpeculation, "type speculation must be on");
2216
2217 const TypePtr* speculative = current_type->speculative();
2218
2219 // Should the klass from the profile be recorded in the speculative type?
2220 if (current_type->would_improve_type(exact_kls, jvms()->depth())) {
2221 const TypeKlassPtr* tklass = TypeKlassPtr::make(exact_kls, Type::trust_interfaces);
2222 const TypeOopPtr* xtype = tklass->as_instance_type();
2223 assert(xtype->klass_is_exact(), "Should be exact");
2224 // Any reason to believe n is not null (from this profiling or a previous one)?
2225 assert(ptr_kind != ProfileAlwaysNull, "impossible here");
2226 const TypePtr* ptr = (ptr_kind == ProfileMaybeNull && current_type->speculative_maybe_null()) ? TypePtr::BOTTOM : TypePtr::NOTNULL;
2227 // record the new speculative type's depth
2228 speculative = xtype->cast_to_ptr_type(ptr->ptr())->is_ptr();
2229 speculative = speculative->with_inline_depth(jvms()->depth());
2230 } else if (current_type->would_improve_ptr(ptr_kind)) {
2231 // Profiling report that null was never seen so we can change the
2232 // speculative type to non null ptr.
2233 if (ptr_kind == ProfileAlwaysNull) {
2234 speculative = TypePtr::NULL_PTR;
2235 } else {
2236 assert(ptr_kind == ProfileNeverNull, "nothing else is an improvement");
2237 const TypePtr* ptr = TypePtr::NOTNULL;
2238 if (speculative != nullptr) {
2239 speculative = speculative->cast_to_ptr_type(ptr->ptr())->is_ptr();
2240 } else {
2241 speculative = ptr;
2242 }
2243 }
2244 }
2245
2246 if (speculative != current_type->speculative()) {
2247 // Build a type with a speculative type (what we think we know
2248 // about the type but will need a guard when we use it)
2249 const TypeOopPtr* spec_type = TypeOopPtr::make(TypePtr::BotPTR, Type::OffsetBot, TypeOopPtr::InstanceBot, speculative);
2250 // We're changing the type, we need a new CheckCast node to carry
2251 // the new type. The new type depends on the control: what
2252 // profiling tells us is only valid from here as far as we can
2253 // tell.
2254 Node* cast = new CheckCastPPNode(control(), n, current_type->remove_speculative()->join_speculative(spec_type));
2255 cast = _gvn.transform(cast);
2256 replace_in_map(n, cast);
2257 n = cast;
2258 }
2259
2260 return n;
2261 }
2262
2263 /**
2264 * Record profiling data from receiver profiling at an invoke with the
2265 * type system so that it can propagate it (speculation)
2266 *
2267 * @param n receiver node
2268 *
2269 * @return node with improved type
2270 */
2271 Node* GraphKit::record_profiled_receiver_for_speculation(Node* n) {
2272 if (!UseTypeSpeculation) {
2273 return n;
2274 }
2275 ciKlass* exact_kls = profile_has_unique_klass();
2276 ProfilePtrKind ptr_kind = ProfileMaybeNull;
2277 if ((java_bc() == Bytecodes::_checkcast ||
2278 java_bc() == Bytecodes::_instanceof ||
2279 java_bc() == Bytecodes::_aastore) &&
2280 method()->method_data()->is_mature()) {
2281 ciProfileData* data = method()->method_data()->bci_to_data(bci());
2282 if (data != nullptr) {
2283 if (!data->as_BitData()->null_seen()) {
2284 ptr_kind = ProfileNeverNull;
2285 } else {
2286 assert(data->is_ReceiverTypeData(), "bad profile data type");
2287 ciReceiverTypeData* call = (ciReceiverTypeData*)data->as_ReceiverTypeData();
2288 uint i = 0;
2289 for (; i < call->row_limit(); i++) {
2290 ciKlass* receiver = call->receiver(i);
2291 if (receiver != nullptr) {
2292 break;
2293 }
2294 }
2295 ptr_kind = (i == call->row_limit()) ? ProfileAlwaysNull : ProfileMaybeNull;
2296 }
2297 }
2298 }
2299 return record_profile_for_speculation(n, exact_kls, ptr_kind);
2300 }
2301
2302 /**
2303 * Record profiling data from argument profiling at an invoke with the
2304 * type system so that it can propagate it (speculation)
2305 *
2306 * @param dest_method target method for the call
2307 * @param bc what invoke bytecode is this?
2308 */
2309 void GraphKit::record_profiled_arguments_for_speculation(ciMethod* dest_method, Bytecodes::Code bc) {
2310 if (!UseTypeSpeculation) {
2311 return;
2312 }
2313 const TypeFunc* tf = TypeFunc::make(dest_method);
2314 int nargs = tf->domain()->cnt() - TypeFunc::Parms;
2315 int skip = Bytecodes::has_receiver(bc) ? 1 : 0;
2316 for (int j = skip, i = 0; j < nargs && i < TypeProfileArgsLimit; j++) {
2317 const Type *targ = tf->domain()->field_at(j + TypeFunc::Parms);
2318 if (is_reference_type(targ->basic_type())) {
2319 ProfilePtrKind ptr_kind = ProfileMaybeNull;
2320 ciKlass* better_type = nullptr;
2321 if (method()->argument_profiled_type(bci(), i, better_type, ptr_kind)) {
2322 record_profile_for_speculation(argument(j), better_type, ptr_kind);
2323 }
2324 i++;
2325 }
2326 }
2327 }
2328
2329 /**
2330 * Record profiling data from parameter profiling at an invoke with
2331 * the type system so that it can propagate it (speculation)
2332 */
2333 void GraphKit::record_profiled_parameters_for_speculation() {
2334 if (!UseTypeSpeculation) {
2335 return;
2336 }
2337 for (int i = 0, j = 0; i < method()->arg_size() ; i++) {
2338 if (_gvn.type(local(i))->isa_oopptr()) {
2339 ProfilePtrKind ptr_kind = ProfileMaybeNull;
2340 ciKlass* better_type = nullptr;
2341 if (method()->parameter_profiled_type(j, better_type, ptr_kind)) {
2342 record_profile_for_speculation(local(i), better_type, ptr_kind);
2343 }
2344 j++;
2345 }
2346 }
2347 }
2348
2349 /**
2350 * Record profiling data from return value profiling at an invoke with
2351 * the type system so that it can propagate it (speculation)
2352 */
2353 void GraphKit::record_profiled_return_for_speculation() {
2354 if (!UseTypeSpeculation) {
2355 return;
2356 }
2357 ProfilePtrKind ptr_kind = ProfileMaybeNull;
2358 ciKlass* better_type = nullptr;
2359 if (method()->return_profiled_type(bci(), better_type, ptr_kind)) {
2360 // If profiling reports a single type for the return value,
2361 // feed it to the type system so it can propagate it as a
2362 // speculative type
2363 record_profile_for_speculation(stack(sp()-1), better_type, ptr_kind);
2364 }
2365 }
2366
2367 void GraphKit::round_double_arguments(ciMethod* dest_method) {
2368 if (Matcher::strict_fp_requires_explicit_rounding) {
2369 // (Note: TypeFunc::make has a cache that makes this fast.)
2370 const TypeFunc* tf = TypeFunc::make(dest_method);
2371 int nargs = tf->domain()->cnt() - TypeFunc::Parms;
2372 for (int j = 0; j < nargs; j++) {
2373 const Type *targ = tf->domain()->field_at(j + TypeFunc::Parms);
2374 if (targ->basic_type() == T_DOUBLE) {
2375 // If any parameters are doubles, they must be rounded before
2376 // the call, dprecision_rounding does gvn.transform
2377 Node *arg = argument(j);
2378 arg = dprecision_rounding(arg);
2379 set_argument(j, arg);
2380 }
2381 }
2382 }
2383 }
2384
2385 // rounding for strict float precision conformance
2386 Node* GraphKit::precision_rounding(Node* n) {
2387 if (Matcher::strict_fp_requires_explicit_rounding) {
2388 #ifdef IA32
2389 if (UseSSE == 0) {
2390 return _gvn.transform(new RoundFloatNode(nullptr, n));
2391 }
2392 #else
2393 Unimplemented();
2394 #endif // IA32
2395 }
2396 return n;
2397 }
2398
2399 // rounding for strict double precision conformance
2400 Node* GraphKit::dprecision_rounding(Node *n) {
2401 if (Matcher::strict_fp_requires_explicit_rounding) {
2402 #ifdef IA32
2403 if (UseSSE < 2) {
2404 return _gvn.transform(new RoundDoubleNode(nullptr, n));
2405 }
2406 #else
2407 Unimplemented();
2408 #endif // IA32
2409 }
2410 return n;
2411 }
2412
2413 //=============================================================================
2414 // Generate a fast path/slow path idiom. Graph looks like:
2415 // [foo] indicates that 'foo' is a parameter
2416 //
2417 // [in] null
2418 // \ /
2419 // CmpP
2420 // Bool ne
2421 // If
2422 // / \
2423 // True False-<2>
2424 // / |
2425 // / cast_not_null
2426 // Load | | ^
2427 // [fast_test] | |
2428 // gvn to opt_test | |
2429 // / \ | <1>
2430 // True False |
2431 // | \\ |
2432 // [slow_call] \[fast_result]
2433 // Ctl Val \ \
2434 // | \ \
2435 // Catch <1> \ \
2436 // / \ ^ \ \
2437 // Ex No_Ex | \ \
2438 // | \ \ | \ <2> \
2439 // ... \ [slow_res] | | \ [null_result]
2440 // \ \--+--+--- | |
2441 // \ | / \ | /
2442 // --------Region Phi
2443 //
2444 //=============================================================================
2445 // Code is structured as a series of driver functions all called 'do_XXX' that
2446 // call a set of helper functions. Helper functions first, then drivers.
2447
2448 //------------------------------null_check_oop---------------------------------
2449 // Null check oop. Set null-path control into Region in slot 3.
2450 // Make a cast-not-nullness use the other not-null control. Return cast.
2451 Node* GraphKit::null_check_oop(Node* value, Node* *null_control,
2452 bool never_see_null,
2453 bool safe_for_replace,
2454 bool speculative) {
2455 // Initial null check taken path
2456 (*null_control) = top();
2457 Node* cast = null_check_common(value, T_OBJECT, false, null_control, speculative);
2458
2459 // Generate uncommon_trap:
2460 if (never_see_null && (*null_control) != top()) {
2461 // If we see an unexpected null at a check-cast we record it and force a
2462 // recompile; the offending check-cast will be compiled to handle nulls.
2463 // If we see more than one offending BCI, then all checkcasts in the
2464 // method will be compiled to handle nulls.
2465 PreserveJVMState pjvms(this);
2466 set_control(*null_control);
2467 replace_in_map(value, null());
2468 Deoptimization::DeoptReason reason = Deoptimization::reason_null_check(speculative);
2469 uncommon_trap(reason,
2470 Deoptimization::Action_make_not_entrant);
2471 (*null_control) = top(); // null path is dead
2472 }
2473 if ((*null_control) == top() && safe_for_replace) {
2474 replace_in_map(value, cast);
2475 }
2476
2477 // Cast away null-ness on the result
2478 return cast;
2479 }
2480
2481 //------------------------------opt_iff----------------------------------------
2482 // Optimize the fast-check IfNode. Set the fast-path region slot 2.
2483 // Return slow-path control.
2484 Node* GraphKit::opt_iff(Node* region, Node* iff) {
2485 IfNode *opt_iff = _gvn.transform(iff)->as_If();
2486
2487 // Fast path taken; set region slot 2
2488 Node *fast_taken = _gvn.transform( new IfFalseNode(opt_iff) );
2489 region->init_req(2,fast_taken); // Capture fast-control
2490
2491 // Fast path not-taken, i.e. slow path
2492 Node *slow_taken = _gvn.transform( new IfTrueNode(opt_iff) );
2493 return slow_taken;
2494 }
2495
2496 //-----------------------------make_runtime_call-------------------------------
2497 Node* GraphKit::make_runtime_call(int flags,
2498 const TypeFunc* call_type, address call_addr,
2499 const char* call_name,
2500 const TypePtr* adr_type,
2501 // The following parms are all optional.
2502 // The first null ends the list.
2503 Node* parm0, Node* parm1,
2504 Node* parm2, Node* parm3,
2505 Node* parm4, Node* parm5,
2506 Node* parm6, Node* parm7) {
2507 assert(call_addr != nullptr, "must not call null targets");
2508
2509 // Slow-path call
2510 bool is_leaf = !(flags & RC_NO_LEAF);
2511 bool has_io = (!is_leaf && !(flags & RC_NO_IO));
2512 if (call_name == nullptr) {
2513 assert(!is_leaf, "must supply name for leaf");
2514 call_name = OptoRuntime::stub_name(call_addr);
2515 }
2516 CallNode* call;
2517 if (!is_leaf) {
2518 call = new CallStaticJavaNode(call_type, call_addr, call_name, adr_type);
2519 } else if (flags & RC_NO_FP) {
2520 call = new CallLeafNoFPNode(call_type, call_addr, call_name, adr_type);
2521 } else if (flags & RC_VECTOR){
2522 uint num_bits = call_type->range()->field_at(TypeFunc::Parms)->is_vect()->length_in_bytes() * BitsPerByte;
2523 call = new CallLeafVectorNode(call_type, call_addr, call_name, adr_type, num_bits);
2524 } else {
2525 call = new CallLeafNode(call_type, call_addr, call_name, adr_type);
2526 }
2527
2528 // The following is similar to set_edges_for_java_call,
2529 // except that the memory effects of the call are restricted to AliasIdxRaw.
2530
2531 // Slow path call has no side-effects, uses few values
2532 bool wide_in = !(flags & RC_NARROW_MEM);
2533 bool wide_out = (C->get_alias_index(adr_type) == Compile::AliasIdxBot);
2534
2535 Node* prev_mem = nullptr;
2536 if (wide_in) {
2537 prev_mem = set_predefined_input_for_runtime_call(call);
2538 } else {
2539 assert(!wide_out, "narrow in => narrow out");
2540 Node* narrow_mem = memory(adr_type);
2541 prev_mem = set_predefined_input_for_runtime_call(call, narrow_mem);
2542 }
2543
2544 // Hook each parm in order. Stop looking at the first null.
2545 if (parm0 != nullptr) { call->init_req(TypeFunc::Parms+0, parm0);
2546 if (parm1 != nullptr) { call->init_req(TypeFunc::Parms+1, parm1);
2547 if (parm2 != nullptr) { call->init_req(TypeFunc::Parms+2, parm2);
2548 if (parm3 != nullptr) { call->init_req(TypeFunc::Parms+3, parm3);
2549 if (parm4 != nullptr) { call->init_req(TypeFunc::Parms+4, parm4);
2550 if (parm5 != nullptr) { call->init_req(TypeFunc::Parms+5, parm5);
2551 if (parm6 != nullptr) { call->init_req(TypeFunc::Parms+6, parm6);
2552 if (parm7 != nullptr) { call->init_req(TypeFunc::Parms+7, parm7);
2553 /* close each nested if ===> */ } } } } } } } }
2554 assert(call->in(call->req()-1) != nullptr, "must initialize all parms");
2555
2556 if (!is_leaf) {
2557 // Non-leaves can block and take safepoints:
2558 add_safepoint_edges(call, ((flags & RC_MUST_THROW) != 0));
2559 }
2560 // Non-leaves can throw exceptions:
2561 if (has_io) {
2562 call->set_req(TypeFunc::I_O, i_o());
2563 }
2564
2565 if (flags & RC_UNCOMMON) {
2566 // Set the count to a tiny probability. Cf. Estimate_Block_Frequency.
2567 // (An "if" probability corresponds roughly to an unconditional count.
2568 // Sort of.)
2569 call->set_cnt(PROB_UNLIKELY_MAG(4));
2570 }
2571
2572 Node* c = _gvn.transform(call);
2573 assert(c == call, "cannot disappear");
2574
2575 if (wide_out) {
2576 // Slow path call has full side-effects.
2577 set_predefined_output_for_runtime_call(call);
2578 } else {
2579 // Slow path call has few side-effects, and/or sets few values.
2580 set_predefined_output_for_runtime_call(call, prev_mem, adr_type);
2581 }
2582
2583 if (has_io) {
2584 set_i_o(_gvn.transform(new ProjNode(call, TypeFunc::I_O)));
2585 }
2586 return call;
2587
2588 }
2589
2590 // i2b
2591 Node* GraphKit::sign_extend_byte(Node* in) {
2592 Node* tmp = _gvn.transform(new LShiftINode(in, _gvn.intcon(24)));
2593 return _gvn.transform(new RShiftINode(tmp, _gvn.intcon(24)));
2594 }
2595
2596 // i2s
2597 Node* GraphKit::sign_extend_short(Node* in) {
2598 Node* tmp = _gvn.transform(new LShiftINode(in, _gvn.intcon(16)));
2599 return _gvn.transform(new RShiftINode(tmp, _gvn.intcon(16)));
2600 }
2601
2602 //------------------------------merge_memory-----------------------------------
2603 // Merge memory from one path into the current memory state.
2604 void GraphKit::merge_memory(Node* new_mem, Node* region, int new_path) {
2605 for (MergeMemStream mms(merged_memory(), new_mem->as_MergeMem()); mms.next_non_empty2(); ) {
2606 Node* old_slice = mms.force_memory();
2607 Node* new_slice = mms.memory2();
2608 if (old_slice != new_slice) {
2609 PhiNode* phi;
2610 if (old_slice->is_Phi() && old_slice->as_Phi()->region() == region) {
2611 if (mms.is_empty()) {
2612 // clone base memory Phi's inputs for this memory slice
2613 assert(old_slice == mms.base_memory(), "sanity");
2614 phi = PhiNode::make(region, nullptr, Type::MEMORY, mms.adr_type(C));
2615 _gvn.set_type(phi, Type::MEMORY);
2616 for (uint i = 1; i < phi->req(); i++) {
2617 phi->init_req(i, old_slice->in(i));
2618 }
2619 } else {
2620 phi = old_slice->as_Phi(); // Phi was generated already
2621 }
2622 } else {
2623 phi = PhiNode::make(region, old_slice, Type::MEMORY, mms.adr_type(C));
2624 _gvn.set_type(phi, Type::MEMORY);
2625 }
2626 phi->set_req(new_path, new_slice);
2627 mms.set_memory(phi);
2628 }
2629 }
2630 }
2631
2632 //------------------------------make_slow_call_ex------------------------------
2633 // Make the exception handler hookups for the slow call
2634 void GraphKit::make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj, bool deoptimize) {
2635 if (stopped()) return;
2636
2637 // Make a catch node with just two handlers: fall-through and catch-all
2638 Node* i_o = _gvn.transform( new ProjNode(call, TypeFunc::I_O, separate_io_proj) );
2639 Node* catc = _gvn.transform( new CatchNode(control(), i_o, 2) );
2640 Node* norm = new CatchProjNode(catc, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci);
2641 _gvn.set_type_bottom(norm);
2642 C->record_for_igvn(norm);
2643 Node* excp = _gvn.transform( new CatchProjNode(catc, CatchProjNode::catch_all_index, CatchProjNode::no_handler_bci) );
2644
2645 { PreserveJVMState pjvms(this);
2646 set_control(excp);
2647 set_i_o(i_o);
2648
2649 if (excp != top()) {
2650 if (deoptimize) {
2651 // Deoptimize if an exception is caught. Don't construct exception state in this case.
2652 uncommon_trap(Deoptimization::Reason_unhandled,
2653 Deoptimization::Action_none);
2654 } else {
2655 // Create an exception state also.
2656 // Use an exact type if the caller has a specific exception.
2657 const Type* ex_type = TypeOopPtr::make_from_klass_unique(ex_klass)->cast_to_ptr_type(TypePtr::NotNull);
2658 Node* ex_oop = new CreateExNode(ex_type, control(), i_o);
2659 add_exception_state(make_exception_state(_gvn.transform(ex_oop)));
2660 }
2661 }
2662 }
2663
2664 // Get the no-exception control from the CatchNode.
2665 set_control(norm);
2666 }
2667
2668 static IfNode* gen_subtype_check_compare(Node* ctrl, Node* in1, Node* in2, BoolTest::mask test, float p, PhaseGVN& gvn, BasicType bt) {
2669 Node* cmp = nullptr;
2670 switch(bt) {
2671 case T_INT: cmp = new CmpINode(in1, in2); break;
2672 case T_ADDRESS: cmp = new CmpPNode(in1, in2); break;
2673 default: fatal("unexpected comparison type %s", type2name(bt));
2674 }
2675 cmp = gvn.transform(cmp);
2676 Node* bol = gvn.transform(new BoolNode(cmp, test));
2677 IfNode* iff = new IfNode(ctrl, bol, p, COUNT_UNKNOWN);
2678 gvn.transform(iff);
2679 if (!bol->is_Con()) gvn.record_for_igvn(iff);
2680 return iff;
2681 }
2682
2683 //-------------------------------gen_subtype_check-----------------------------
2684 // Generate a subtyping check. Takes as input the subtype and supertype.
2685 // Returns 2 values: sets the default control() to the true path and returns
2686 // the false path. Only reads invariant memory; sets no (visible) memory.
2687 // The PartialSubtypeCheckNode sets the hidden 1-word cache in the encoding
2688 // but that's not exposed to the optimizer. This call also doesn't take in an
2689 // Object; if you wish to check an Object you need to load the Object's class
2690 // prior to coming here.
2691 Node* Phase::gen_subtype_check(Node* subklass, Node* superklass, Node** ctrl, Node* mem, PhaseGVN& gvn,
2692 ciMethod* method, int bci) {
2693 Compile* C = gvn.C;
2694 if ((*ctrl)->is_top()) {
2695 return C->top();
2696 }
2697
2698 // Fast check for identical types, perhaps identical constants.
2699 // The types can even be identical non-constants, in cases
2700 // involving Array.newInstance, Object.clone, etc.
2701 if (subklass == superklass)
2702 return C->top(); // false path is dead; no test needed.
2703
2704 if (gvn.type(superklass)->singleton()) {
2705 const TypeKlassPtr* superk = gvn.type(superklass)->is_klassptr();
2706 const TypeKlassPtr* subk = gvn.type(subklass)->is_klassptr();
2707
2708 // In the common case of an exact superklass, try to fold up the
2709 // test before generating code. You may ask, why not just generate
2710 // the code and then let it fold up? The answer is that the generated
2711 // code will necessarily include null checks, which do not always
2712 // completely fold away. If they are also needless, then they turn
2713 // into a performance loss. Example:
2714 // Foo[] fa = blah(); Foo x = fa[0]; fa[1] = x;
2715 // Here, the type of 'fa' is often exact, so the store check
2716 // of fa[1]=x will fold up, without testing the nullness of x.
2717 //
2718 // At macro expansion, we would have already folded the SubTypeCheckNode
2719 // being expanded here because we always perform the static sub type
2720 // check in SubTypeCheckNode::sub() regardless of whether
2721 // StressReflectiveCode is set or not. We can therefore skip this
2722 // static check when StressReflectiveCode is on.
2723 switch (C->static_subtype_check(superk, subk)) {
2724 case Compile::SSC_always_false:
2725 {
2726 Node* always_fail = *ctrl;
2727 *ctrl = gvn.C->top();
2728 return always_fail;
2729 }
2730 case Compile::SSC_always_true:
2731 return C->top();
2732 case Compile::SSC_easy_test:
2733 {
2734 // Just do a direct pointer compare and be done.
2735 IfNode* iff = gen_subtype_check_compare(*ctrl, subklass, superklass, BoolTest::eq, PROB_STATIC_FREQUENT, gvn, T_ADDRESS);
2736 *ctrl = gvn.transform(new IfTrueNode(iff));
2737 return gvn.transform(new IfFalseNode(iff));
2738 }
2739 case Compile::SSC_full_test:
2740 break;
2741 default:
2742 ShouldNotReachHere();
2743 }
2744 }
2745
2746 // %%% Possible further optimization: Even if the superklass is not exact,
2747 // if the subklass is the unique subtype of the superklass, the check
2748 // will always succeed. We could leave a dependency behind to ensure this.
2749
2750 // First load the super-klass's check-offset
2751 Node *p1 = gvn.transform(new AddPNode(superklass, superklass, gvn.MakeConX(in_bytes(Klass::super_check_offset_offset()))));
2752 Node* m = C->immutable_memory();
2753 Node *chk_off = gvn.transform(new LoadINode(nullptr, m, p1, gvn.type(p1)->is_ptr(), TypeInt::INT, MemNode::unordered));
2754 int cacheoff_con = in_bytes(Klass::secondary_super_cache_offset());
2755 const TypeInt* chk_off_t = chk_off->Value(&gvn)->isa_int();
2756 int chk_off_con = (chk_off_t != nullptr && chk_off_t->is_con()) ? chk_off_t->get_con() : cacheoff_con;
2757 bool might_be_cache = (chk_off_con == cacheoff_con);
2758
2759 // Load from the sub-klass's super-class display list, or a 1-word cache of
2760 // the secondary superclass list, or a failing value with a sentinel offset
2761 // if the super-klass is an interface or exceptionally deep in the Java
2762 // hierarchy and we have to scan the secondary superclass list the hard way.
2763 // Worst-case type is a little odd: null is allowed as a result (usually
2764 // klass loads can never produce a null).
2765 Node *chk_off_X = chk_off;
2766 #ifdef _LP64
2767 chk_off_X = gvn.transform(new ConvI2LNode(chk_off_X));
2768 #endif
2769 Node *p2 = gvn.transform(new AddPNode(subklass,subklass,chk_off_X));
2770 // For some types like interfaces the following loadKlass is from a 1-word
2771 // cache which is mutable so can't use immutable memory. Other
2772 // types load from the super-class display table which is immutable.
2773 Node *kmem = C->immutable_memory();
2774 // secondary_super_cache is not immutable but can be treated as such because:
2775 // - no ideal node writes to it in a way that could cause an
2776 // incorrect/missed optimization of the following Load.
2777 // - it's a cache so, worse case, not reading the latest value
2778 // wouldn't cause incorrect execution
2779 if (might_be_cache && mem != nullptr) {
2780 kmem = mem->is_MergeMem() ? mem->as_MergeMem()->memory_at(C->get_alias_index(gvn.type(p2)->is_ptr())) : mem;
2781 }
2782 Node* nkls = gvn.transform(LoadKlassNode::make(gvn, kmem, p2, gvn.type(p2)->is_ptr(), TypeInstKlassPtr::OBJECT_OR_NULL));
2783
2784 // Compile speed common case: ARE a subtype and we canNOT fail
2785 if (superklass == nkls) {
2786 return C->top(); // false path is dead; no test needed.
2787 }
2788
2789 // Gather the various success & failures here
2790 RegionNode* r_not_subtype = new RegionNode(3);
2791 gvn.record_for_igvn(r_not_subtype);
2792 RegionNode* r_ok_subtype = new RegionNode(4);
2793 gvn.record_for_igvn(r_ok_subtype);
2794
2795 // If we might perform an expensive check, first try to take advantage of profile data that was attached to the
2796 // SubTypeCheck node
2797 if (might_be_cache && method != nullptr && VM_Version::profile_all_receivers_at_type_check()) {
2798 ciCallProfile profile = method->call_profile_at_bci(bci);
2799 float total_prob = 0;
2800 for (int i = 0; profile.has_receiver(i); ++i) {
2801 float prob = profile.receiver_prob(i);
2802 total_prob += prob;
2803 }
2804 if (total_prob * 100. >= TypeProfileSubTypeCheckCommonThreshold) {
2805 const TypeKlassPtr* superk = gvn.type(superklass)->is_klassptr();
2806 for (int i = 0; profile.has_receiver(i); ++i) {
2807 ciKlass* klass = profile.receiver(i);
2808 const TypeKlassPtr* klass_t = TypeKlassPtr::make(klass);
2809 Compile::SubTypeCheckResult result = C->static_subtype_check(superk, klass_t);
2810 if (result != Compile::SSC_always_true && result != Compile::SSC_always_false) {
2811 continue;
2812 }
2813 float prob = profile.receiver_prob(i);
2814 ConNode* klass_node = gvn.makecon(klass_t);
2815 IfNode* iff = gen_subtype_check_compare(*ctrl, subklass, klass_node, BoolTest::eq, prob, gvn, T_ADDRESS);
2816 Node* iftrue = gvn.transform(new IfTrueNode(iff));
2817
2818 if (result == Compile::SSC_always_true) {
2819 r_ok_subtype->add_req(iftrue);
2820 } else {
2821 assert(result == Compile::SSC_always_false, "");
2822 r_not_subtype->add_req(iftrue);
2823 }
2824 *ctrl = gvn.transform(new IfFalseNode(iff));
2825 }
2826 }
2827 }
2828
2829 // See if we get an immediate positive hit. Happens roughly 83% of the
2830 // time. Test to see if the value loaded just previously from the subklass
2831 // is exactly the superklass.
2832 IfNode *iff1 = gen_subtype_check_compare(*ctrl, superklass, nkls, BoolTest::eq, PROB_LIKELY(0.83f), gvn, T_ADDRESS);
2833 Node *iftrue1 = gvn.transform( new IfTrueNode (iff1));
2834 *ctrl = gvn.transform(new IfFalseNode(iff1));
2835
2836 // Compile speed common case: Check for being deterministic right now. If
2837 // chk_off is a constant and not equal to cacheoff then we are NOT a
2838 // subklass. In this case we need exactly the 1 test above and we can
2839 // return those results immediately.
2840 if (!might_be_cache) {
2841 Node* not_subtype_ctrl = *ctrl;
2842 *ctrl = iftrue1; // We need exactly the 1 test above
2843 PhaseIterGVN* igvn = gvn.is_IterGVN();
2844 if (igvn != nullptr) {
2845 igvn->remove_globally_dead_node(r_ok_subtype);
2846 igvn->remove_globally_dead_node(r_not_subtype);
2847 }
2848 return not_subtype_ctrl;
2849 }
2850
2851 r_ok_subtype->init_req(1, iftrue1);
2852
2853 // Check for immediate negative hit. Happens roughly 11% of the time (which
2854 // is roughly 63% of the remaining cases). Test to see if the loaded
2855 // check-offset points into the subklass display list or the 1-element
2856 // cache. If it points to the display (and NOT the cache) and the display
2857 // missed then it's not a subtype.
2858 Node *cacheoff = gvn.intcon(cacheoff_con);
2859 IfNode *iff2 = gen_subtype_check_compare(*ctrl, chk_off, cacheoff, BoolTest::ne, PROB_LIKELY(0.63f), gvn, T_INT);
2860 r_not_subtype->init_req(1, gvn.transform(new IfTrueNode (iff2)));
2861 *ctrl = gvn.transform(new IfFalseNode(iff2));
2862
2863 // Check for self. Very rare to get here, but it is taken 1/3 the time.
2864 // No performance impact (too rare) but allows sharing of secondary arrays
2865 // which has some footprint reduction.
2866 IfNode *iff3 = gen_subtype_check_compare(*ctrl, subklass, superklass, BoolTest::eq, PROB_LIKELY(0.36f), gvn, T_ADDRESS);
2867 r_ok_subtype->init_req(2, gvn.transform(new IfTrueNode(iff3)));
2868 *ctrl = gvn.transform(new IfFalseNode(iff3));
2869
2870 // -- Roads not taken here: --
2871 // We could also have chosen to perform the self-check at the beginning
2872 // of this code sequence, as the assembler does. This would not pay off
2873 // the same way, since the optimizer, unlike the assembler, can perform
2874 // static type analysis to fold away many successful self-checks.
2875 // Non-foldable self checks work better here in second position, because
2876 // the initial primary superclass check subsumes a self-check for most
2877 // types. An exception would be a secondary type like array-of-interface,
2878 // which does not appear in its own primary supertype display.
2879 // Finally, we could have chosen to move the self-check into the
2880 // PartialSubtypeCheckNode, and from there out-of-line in a platform
2881 // dependent manner. But it is worthwhile to have the check here,
2882 // where it can be perhaps be optimized. The cost in code space is
2883 // small (register compare, branch).
2884
2885 // Now do a linear scan of the secondary super-klass array. Again, no real
2886 // performance impact (too rare) but it's gotta be done.
2887 // Since the code is rarely used, there is no penalty for moving it
2888 // out of line, and it can only improve I-cache density.
2889 // The decision to inline or out-of-line this final check is platform
2890 // dependent, and is found in the AD file definition of PartialSubtypeCheck.
2891 Node* psc = gvn.transform(
2892 new PartialSubtypeCheckNode(*ctrl, subklass, superklass));
2893
2894 IfNode *iff4 = gen_subtype_check_compare(*ctrl, psc, gvn.zerocon(T_OBJECT), BoolTest::ne, PROB_FAIR, gvn, T_ADDRESS);
2895 r_not_subtype->init_req(2, gvn.transform(new IfTrueNode (iff4)));
2896 r_ok_subtype ->init_req(3, gvn.transform(new IfFalseNode(iff4)));
2897
2898 // Return false path; set default control to true path.
2899 *ctrl = gvn.transform(r_ok_subtype);
2900 return gvn.transform(r_not_subtype);
2901 }
2902
2903 Node* GraphKit::gen_subtype_check(Node* obj_or_subklass, Node* superklass) {
2904 bool expand_subtype_check = C->post_loop_opts_phase(); // macro node expansion is over
2905 if (expand_subtype_check) {
2906 MergeMemNode* mem = merged_memory();
2907 Node* ctrl = control();
2908 Node* subklass = obj_or_subklass;
2909 if (!_gvn.type(obj_or_subklass)->isa_klassptr()) {
2910 subklass = load_object_klass(obj_or_subklass);
2911 }
2912
2913 Node* n = Phase::gen_subtype_check(subklass, superklass, &ctrl, mem, _gvn, method(), bci());
2914 set_control(ctrl);
2915 return n;
2916 }
2917
2918 Node* check = _gvn.transform(new SubTypeCheckNode(C, obj_or_subklass, superklass, method(), bci()));
2919 Node* bol = _gvn.transform(new BoolNode(check, BoolTest::eq));
2920 IfNode* iff = create_and_xform_if(control(), bol, PROB_STATIC_FREQUENT, COUNT_UNKNOWN);
2921 set_control(_gvn.transform(new IfTrueNode(iff)));
2922 return _gvn.transform(new IfFalseNode(iff));
2923 }
2924
2925 // Profile-driven exact type check:
2926 Node* GraphKit::type_check_receiver(Node* receiver, ciKlass* klass,
2927 float prob,
2928 Node* *casted_receiver) {
2929 assert(!klass->is_interface(), "no exact type check on interfaces");
2930
2931 const TypeKlassPtr* tklass = TypeKlassPtr::make(klass, Type::trust_interfaces);
2932 Node* recv_klass = load_object_klass(receiver);
2933 Node* want_klass = makecon(tklass);
2934 Node* cmp = _gvn.transform(new CmpPNode(recv_klass, want_klass));
2935 Node* bol = _gvn.transform(new BoolNode(cmp, BoolTest::eq));
2936 IfNode* iff = create_and_xform_if(control(), bol, prob, COUNT_UNKNOWN);
2937 set_control( _gvn.transform(new IfTrueNode (iff)));
2938 Node* fail = _gvn.transform(new IfFalseNode(iff));
2939
2940 if (!stopped()) {
2941 const TypeOopPtr* receiver_type = _gvn.type(receiver)->isa_oopptr();
2942 const TypeOopPtr* recvx_type = tklass->as_instance_type();
2943 assert(recvx_type->klass_is_exact(), "");
2944
2945 if (!receiver_type->higher_equal(recvx_type)) { // ignore redundant casts
2946 // Subsume downstream occurrences of receiver with a cast to
2947 // recv_xtype, since now we know what the type will be.
2948 Node* cast = new CheckCastPPNode(control(), receiver, recvx_type);
2949 (*casted_receiver) = _gvn.transform(cast);
2950 assert(!(*casted_receiver)->is_top(), "that path should be unreachable");
2951 // (User must make the replace_in_map call.)
2952 }
2953 }
2954
2955 return fail;
2956 }
2957
2958 //------------------------------subtype_check_receiver-------------------------
2959 Node* GraphKit::subtype_check_receiver(Node* receiver, ciKlass* klass,
2960 Node** casted_receiver) {
2961 const TypeKlassPtr* tklass = TypeKlassPtr::make(klass, Type::trust_interfaces)->try_improve();
2962 Node* want_klass = makecon(tklass);
2963
2964 Node* slow_ctl = gen_subtype_check(receiver, want_klass);
2965
2966 // Ignore interface type information until interface types are properly tracked.
2967 if (!stopped() && !klass->is_interface()) {
2968 const TypeOopPtr* receiver_type = _gvn.type(receiver)->isa_oopptr();
2969 const TypeOopPtr* recv_type = tklass->cast_to_exactness(false)->is_klassptr()->as_instance_type();
2970 if (!receiver_type->higher_equal(recv_type)) { // ignore redundant casts
2971 Node* cast = new CheckCastPPNode(control(), receiver, recv_type);
2972 (*casted_receiver) = _gvn.transform(cast);
2973 }
2974 }
2975
2976 return slow_ctl;
2977 }
2978
2979 //------------------------------seems_never_null-------------------------------
2980 // Use null_seen information if it is available from the profile.
2981 // If we see an unexpected null at a type check we record it and force a
2982 // recompile; the offending check will be recompiled to handle nulls.
2983 // If we see several offending BCIs, then all checks in the
2984 // method will be recompiled.
2985 bool GraphKit::seems_never_null(Node* obj, ciProfileData* data, bool& speculating) {
2986 speculating = !_gvn.type(obj)->speculative_maybe_null();
2987 Deoptimization::DeoptReason reason = Deoptimization::reason_null_check(speculating);
2988 if (UncommonNullCast // Cutout for this technique
2989 && obj != null() // And not the -Xcomp stupid case?
2990 && !too_many_traps(reason)
2991 ) {
2992 if (speculating) {
2993 return true;
2994 }
2995 if (data == nullptr)
2996 // Edge case: no mature data. Be optimistic here.
2997 return true;
2998 // If the profile has not seen a null, assume it won't happen.
2999 assert(java_bc() == Bytecodes::_checkcast ||
3000 java_bc() == Bytecodes::_instanceof ||
3001 java_bc() == Bytecodes::_aastore, "MDO must collect null_seen bit here");
3002 return !data->as_BitData()->null_seen();
3003 }
3004 speculating = false;
3005 return false;
3006 }
3007
3008 void GraphKit::guard_klass_being_initialized(Node* klass) {
3009 int init_state_off = in_bytes(InstanceKlass::init_state_offset());
3010 Node* adr = basic_plus_adr(top(), klass, init_state_off);
3011 Node* init_state = LoadNode::make(_gvn, nullptr, immutable_memory(), adr,
3012 adr->bottom_type()->is_ptr(), TypeInt::BYTE,
3013 T_BYTE, MemNode::acquire);
3014 init_state = _gvn.transform(init_state);
3015
3016 Node* being_initialized_state = makecon(TypeInt::make(InstanceKlass::being_initialized));
3017
3018 Node* chk = _gvn.transform(new CmpINode(being_initialized_state, init_state));
3019 Node* tst = _gvn.transform(new BoolNode(chk, BoolTest::eq));
3020
3021 { BuildCutout unless(this, tst, PROB_MAX);
3022 uncommon_trap(Deoptimization::Reason_initialized, Deoptimization::Action_reinterpret);
3023 }
3024 }
3025
3026 void GraphKit::guard_init_thread(Node* klass) {
3027 int init_thread_off = in_bytes(InstanceKlass::init_thread_offset());
3028 Node* adr = basic_plus_adr(top(), klass, init_thread_off);
3029
3030 Node* init_thread = LoadNode::make(_gvn, nullptr, immutable_memory(), adr,
3031 adr->bottom_type()->is_ptr(), TypePtr::NOTNULL,
3032 T_ADDRESS, MemNode::unordered);
3033 init_thread = _gvn.transform(init_thread);
3034
3035 Node* cur_thread = _gvn.transform(new ThreadLocalNode());
3036
3037 Node* chk = _gvn.transform(new CmpPNode(cur_thread, init_thread));
3038 Node* tst = _gvn.transform(new BoolNode(chk, BoolTest::eq));
3039
3040 { BuildCutout unless(this, tst, PROB_MAX);
3041 uncommon_trap(Deoptimization::Reason_uninitialized, Deoptimization::Action_none);
3042 }
3043 }
3044
3045 void GraphKit::clinit_barrier(ciInstanceKlass* ik, ciMethod* context) {
3046 if (ik->is_being_initialized()) {
3047 if (C->needs_clinit_barrier(ik, context)) {
3048 Node* klass = makecon(TypeKlassPtr::make(ik));
3049 guard_klass_being_initialized(klass);
3050 guard_init_thread(klass);
3051 insert_mem_bar(Op_MemBarCPUOrder);
3052 }
3053 } else if (ik->is_initialized()) {
3054 return; // no barrier needed
3055 } else {
3056 uncommon_trap(Deoptimization::Reason_uninitialized,
3057 Deoptimization::Action_reinterpret,
3058 nullptr);
3059 }
3060 }
3061
3062 //------------------------maybe_cast_profiled_receiver-------------------------
3063 // If the profile has seen exactly one type, narrow to exactly that type.
3064 // Subsequent type checks will always fold up.
3065 Node* GraphKit::maybe_cast_profiled_receiver(Node* not_null_obj,
3066 const TypeKlassPtr* require_klass,
3067 ciKlass* spec_klass,
3068 bool safe_for_replace) {
3069 if (!UseTypeProfile || !TypeProfileCasts) return nullptr;
3070
3071 Deoptimization::DeoptReason reason = Deoptimization::reason_class_check(spec_klass != nullptr);
3072
3073 // Make sure we haven't already deoptimized from this tactic.
3074 if (too_many_traps_or_recompiles(reason))
3075 return nullptr;
3076
3077 // (No, this isn't a call, but it's enough like a virtual call
3078 // to use the same ciMethod accessor to get the profile info...)
3079 // If we have a speculative type use it instead of profiling (which
3080 // may not help us)
3081 ciKlass* exact_kls = spec_klass == nullptr ? profile_has_unique_klass() : spec_klass;
3082 if (exact_kls != nullptr) {// no cast failures here
3083 if (require_klass == nullptr ||
3084 C->static_subtype_check(require_klass, TypeKlassPtr::make(exact_kls, Type::trust_interfaces)) == Compile::SSC_always_true) {
3085 // If we narrow the type to match what the type profile sees or
3086 // the speculative type, we can then remove the rest of the
3087 // cast.
3088 // This is a win, even if the exact_kls is very specific,
3089 // because downstream operations, such as method calls,
3090 // will often benefit from the sharper type.
3091 Node* exact_obj = not_null_obj; // will get updated in place...
3092 Node* slow_ctl = type_check_receiver(exact_obj, exact_kls, 1.0,
3093 &exact_obj);
3094 { PreserveJVMState pjvms(this);
3095 set_control(slow_ctl);
3096 uncommon_trap_exact(reason, Deoptimization::Action_maybe_recompile);
3097 }
3098 if (safe_for_replace) {
3099 replace_in_map(not_null_obj, exact_obj);
3100 }
3101 return exact_obj;
3102 }
3103 // assert(ssc == Compile::SSC_always_true)... except maybe the profile lied to us.
3104 }
3105
3106 return nullptr;
3107 }
3108
3109 /**
3110 * Cast obj to type and emit guard unless we had too many traps here
3111 * already
3112 *
3113 * @param obj node being casted
3114 * @param type type to cast the node to
3115 * @param not_null true if we know node cannot be null
3116 */
3117 Node* GraphKit::maybe_cast_profiled_obj(Node* obj,
3118 ciKlass* type,
3119 bool not_null) {
3120 if (stopped()) {
3121 return obj;
3122 }
3123
3124 // type is null if profiling tells us this object is always null
3125 if (type != nullptr) {
3126 Deoptimization::DeoptReason class_reason = Deoptimization::Reason_speculate_class_check;
3127 Deoptimization::DeoptReason null_reason = Deoptimization::Reason_speculate_null_check;
3128
3129 if (!too_many_traps_or_recompiles(null_reason) &&
3130 !too_many_traps_or_recompiles(class_reason)) {
3131 Node* not_null_obj = nullptr;
3132 // not_null is true if we know the object is not null and
3133 // there's no need for a null check
3134 if (!not_null) {
3135 Node* null_ctl = top();
3136 not_null_obj = null_check_oop(obj, &null_ctl, true, true, true);
3137 assert(null_ctl->is_top(), "no null control here");
3138 } else {
3139 not_null_obj = obj;
3140 }
3141
3142 Node* exact_obj = not_null_obj;
3143 ciKlass* exact_kls = type;
3144 Node* slow_ctl = type_check_receiver(exact_obj, exact_kls, 1.0,
3145 &exact_obj);
3146 {
3147 PreserveJVMState pjvms(this);
3148 set_control(slow_ctl);
3149 uncommon_trap_exact(class_reason, Deoptimization::Action_maybe_recompile);
3150 }
3151 replace_in_map(not_null_obj, exact_obj);
3152 obj = exact_obj;
3153 }
3154 } else {
3155 if (!too_many_traps_or_recompiles(Deoptimization::Reason_null_assert)) {
3156 Node* exact_obj = null_assert(obj);
3157 replace_in_map(obj, exact_obj);
3158 obj = exact_obj;
3159 }
3160 }
3161 return obj;
3162 }
3163
3164 //-------------------------------gen_instanceof--------------------------------
3165 // Generate an instance-of idiom. Used by both the instance-of bytecode
3166 // and the reflective instance-of call.
3167 Node* GraphKit::gen_instanceof(Node* obj, Node* superklass, bool safe_for_replace) {
3168 kill_dead_locals(); // Benefit all the uncommon traps
3169 assert( !stopped(), "dead parse path should be checked in callers" );
3170 assert(!TypePtr::NULL_PTR->higher_equal(_gvn.type(superklass)->is_klassptr()),
3171 "must check for not-null not-dead klass in callers");
3172
3173 // Make the merge point
3174 enum { _obj_path = 1, _fail_path, _null_path, PATH_LIMIT };
3175 RegionNode* region = new RegionNode(PATH_LIMIT);
3176 Node* phi = new PhiNode(region, TypeInt::BOOL);
3177 C->set_has_split_ifs(true); // Has chance for split-if optimization
3178
3179 ciProfileData* data = nullptr;
3180 if (java_bc() == Bytecodes::_instanceof) { // Only for the bytecode
3181 data = method()->method_data()->bci_to_data(bci());
3182 }
3183 bool speculative_not_null = false;
3184 bool never_see_null = (ProfileDynamicTypes // aggressive use of profile
3185 && seems_never_null(obj, data, speculative_not_null));
3186
3187 // Null check; get casted pointer; set region slot 3
3188 Node* null_ctl = top();
3189 Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace, speculative_not_null);
3190
3191 // If not_null_obj is dead, only null-path is taken
3192 if (stopped()) { // Doing instance-of on a null?
3193 set_control(null_ctl);
3194 return intcon(0);
3195 }
3196 region->init_req(_null_path, null_ctl);
3197 phi ->init_req(_null_path, intcon(0)); // Set null path value
3198 if (null_ctl == top()) {
3199 // Do this eagerly, so that pattern matches like is_diamond_phi
3200 // will work even during parsing.
3201 assert(_null_path == PATH_LIMIT-1, "delete last");
3202 region->del_req(_null_path);
3203 phi ->del_req(_null_path);
3204 }
3205
3206 // Do we know the type check always succeed?
3207 bool known_statically = false;
3208 if (_gvn.type(superklass)->singleton()) {
3209 const TypeKlassPtr* superk = _gvn.type(superklass)->is_klassptr();
3210 const TypeKlassPtr* subk = _gvn.type(obj)->is_oopptr()->as_klass_type();
3211 if (subk->is_loaded()) {
3212 int static_res = C->static_subtype_check(superk, subk);
3213 known_statically = (static_res == Compile::SSC_always_true || static_res == Compile::SSC_always_false);
3214 }
3215 }
3216
3217 if (!known_statically) {
3218 const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
3219 // We may not have profiling here or it may not help us. If we
3220 // have a speculative type use it to perform an exact cast.
3221 ciKlass* spec_obj_type = obj_type->speculative_type();
3222 if (spec_obj_type != nullptr || (ProfileDynamicTypes && data != nullptr)) {
3223 Node* cast_obj = maybe_cast_profiled_receiver(not_null_obj, nullptr, spec_obj_type, safe_for_replace);
3224 if (stopped()) { // Profile disagrees with this path.
3225 set_control(null_ctl); // Null is the only remaining possibility.
3226 return intcon(0);
3227 }
3228 if (cast_obj != nullptr) {
3229 not_null_obj = cast_obj;
3230 }
3231 }
3232 }
3233
3234 // Generate the subtype check
3235 Node* not_subtype_ctrl = gen_subtype_check(not_null_obj, superklass);
3236
3237 // Plug in the success path to the general merge in slot 1.
3238 region->init_req(_obj_path, control());
3239 phi ->init_req(_obj_path, intcon(1));
3240
3241 // Plug in the failing path to the general merge in slot 2.
3242 region->init_req(_fail_path, not_subtype_ctrl);
3243 phi ->init_req(_fail_path, intcon(0));
3244
3245 // Return final merged results
3246 set_control( _gvn.transform(region) );
3247 record_for_igvn(region);
3248
3249 // If we know the type check always succeeds then we don't use the
3250 // profiling data at this bytecode. Don't lose it, feed it to the
3251 // type system as a speculative type.
3252 if (safe_for_replace) {
3253 Node* casted_obj = record_profiled_receiver_for_speculation(obj);
3254 replace_in_map(obj, casted_obj);
3255 }
3256
3257 return _gvn.transform(phi);
3258 }
3259
3260 //-------------------------------gen_checkcast---------------------------------
3261 // Generate a checkcast idiom. Used by both the checkcast bytecode and the
3262 // array store bytecode. Stack must be as-if BEFORE doing the bytecode so the
3263 // uncommon-trap paths work. Adjust stack after this call.
3264 // If failure_control is supplied and not null, it is filled in with
3265 // the control edge for the cast failure. Otherwise, an appropriate
3266 // uncommon trap or exception is thrown.
3267 Node* GraphKit::gen_checkcast(Node *obj, Node* superklass,
3268 Node* *failure_control) {
3269 kill_dead_locals(); // Benefit all the uncommon traps
3270 const TypeKlassPtr* klass_ptr_type = _gvn.type(superklass)->is_klassptr();
3271 const TypeKlassPtr* improved_klass_ptr_type = klass_ptr_type->try_improve();
3272 const TypeOopPtr* toop = improved_klass_ptr_type->cast_to_exactness(false)->as_instance_type();
3273
3274 // Fast cutout: Check the case that the cast is vacuously true.
3275 // This detects the common cases where the test will short-circuit
3276 // away completely. We do this before we perform the null check,
3277 // because if the test is going to turn into zero code, we don't
3278 // want a residual null check left around. (Causes a slowdown,
3279 // for example, in some objArray manipulations, such as a[i]=a[j].)
3280 if (improved_klass_ptr_type->singleton()) {
3281 const TypeOopPtr* objtp = _gvn.type(obj)->isa_oopptr();
3282 if (objtp != nullptr) {
3283 switch (C->static_subtype_check(improved_klass_ptr_type, objtp->as_klass_type())) {
3284 case Compile::SSC_always_true:
3285 // If we know the type check always succeed then we don't use
3286 // the profiling data at this bytecode. Don't lose it, feed it
3287 // to the type system as a speculative type.
3288 return record_profiled_receiver_for_speculation(obj);
3289 case Compile::SSC_always_false:
3290 // It needs a null check because a null will *pass* the cast check.
3291 // A non-null value will always produce an exception.
3292 if (!objtp->maybe_null()) {
3293 bool is_aastore = (java_bc() == Bytecodes::_aastore);
3294 Deoptimization::DeoptReason reason = is_aastore ?
3295 Deoptimization::Reason_array_check : Deoptimization::Reason_class_check;
3296 builtin_throw(reason);
3297 return top();
3298 } else if (!too_many_traps_or_recompiles(Deoptimization::Reason_null_assert)) {
3299 return null_assert(obj);
3300 }
3301 break; // Fall through to full check
3302 default:
3303 break;
3304 }
3305 }
3306 }
3307
3308 ciProfileData* data = nullptr;
3309 bool safe_for_replace = false;
3310 if (failure_control == nullptr) { // use MDO in regular case only
3311 assert(java_bc() == Bytecodes::_aastore ||
3312 java_bc() == Bytecodes::_checkcast,
3313 "interpreter profiles type checks only for these BCs");
3314 data = method()->method_data()->bci_to_data(bci());
3315 safe_for_replace = true;
3316 }
3317
3318 // Make the merge point
3319 enum { _obj_path = 1, _null_path, PATH_LIMIT };
3320 RegionNode* region = new RegionNode(PATH_LIMIT);
3321 Node* phi = new PhiNode(region, toop);
3322 C->set_has_split_ifs(true); // Has chance for split-if optimization
3323
3324 // Use null-cast information if it is available
3325 bool speculative_not_null = false;
3326 bool never_see_null = ((failure_control == nullptr) // regular case only
3327 && seems_never_null(obj, data, speculative_not_null));
3328
3329 // Null check; get casted pointer; set region slot 3
3330 Node* null_ctl = top();
3331 Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace, speculative_not_null);
3332
3333 // If not_null_obj is dead, only null-path is taken
3334 if (stopped()) { // Doing instance-of on a null?
3335 set_control(null_ctl);
3336 return null();
3337 }
3338 region->init_req(_null_path, null_ctl);
3339 phi ->init_req(_null_path, null()); // Set null path value
3340 if (null_ctl == top()) {
3341 // Do this eagerly, so that pattern matches like is_diamond_phi
3342 // will work even during parsing.
3343 assert(_null_path == PATH_LIMIT-1, "delete last");
3344 region->del_req(_null_path);
3345 phi ->del_req(_null_path);
3346 }
3347
3348 Node* cast_obj = nullptr;
3349 if (improved_klass_ptr_type->klass_is_exact()) {
3350 // The following optimization tries to statically cast the speculative type of the object
3351 // (for example obtained during profiling) to the type of the superklass and then do a
3352 // dynamic check that the type of the object is what we expect. To work correctly
3353 // for checkcast and aastore the type of superklass should be exact.
3354 const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
3355 // We may not have profiling here or it may not help us. If we have
3356 // a speculative type use it to perform an exact cast.
3357 ciKlass* spec_obj_type = obj_type->speculative_type();
3358 if (spec_obj_type != nullptr || data != nullptr) {
3359 cast_obj = maybe_cast_profiled_receiver(not_null_obj, improved_klass_ptr_type, spec_obj_type, safe_for_replace);
3360 if (cast_obj != nullptr) {
3361 if (failure_control != nullptr) // failure is now impossible
3362 (*failure_control) = top();
3363 // adjust the type of the phi to the exact klass:
3364 phi->raise_bottom_type(_gvn.type(cast_obj)->meet_speculative(TypePtr::NULL_PTR));
3365 }
3366 }
3367 }
3368
3369 if (cast_obj == nullptr) {
3370 // Generate the subtype check
3371 Node* improved_superklass = superklass;
3372 if (improved_klass_ptr_type != klass_ptr_type && improved_klass_ptr_type->singleton()) {
3373 improved_superklass = makecon(improved_klass_ptr_type);
3374 }
3375 Node* not_subtype_ctrl = gen_subtype_check(not_null_obj, improved_superklass);
3376
3377 // Plug in success path into the merge
3378 cast_obj = _gvn.transform(new CheckCastPPNode(control(), not_null_obj, toop));
3379 // Failure path ends in uncommon trap (or may be dead - failure impossible)
3380 if (failure_control == nullptr) {
3381 if (not_subtype_ctrl != top()) { // If failure is possible
3382 PreserveJVMState pjvms(this);
3383 set_control(not_subtype_ctrl);
3384 bool is_aastore = (java_bc() == Bytecodes::_aastore);
3385 Deoptimization::DeoptReason reason = is_aastore ?
3386 Deoptimization::Reason_array_check : Deoptimization::Reason_class_check;
3387 builtin_throw(reason);
3388 }
3389 } else {
3390 (*failure_control) = not_subtype_ctrl;
3391 }
3392 }
3393
3394 region->init_req(_obj_path, control());
3395 phi ->init_req(_obj_path, cast_obj);
3396
3397 // A merge of null or Casted-NotNull obj
3398 Node* res = _gvn.transform(phi);
3399
3400 // Note I do NOT always 'replace_in_map(obj,result)' here.
3401 // if( tk->klass()->can_be_primary_super() )
3402 // This means that if I successfully store an Object into an array-of-String
3403 // I 'forget' that the Object is really now known to be a String. I have to
3404 // do this because we don't have true union types for interfaces - if I store
3405 // a Baz into an array-of-Interface and then tell the optimizer it's an
3406 // Interface, I forget that it's also a Baz and cannot do Baz-like field
3407 // references to it. FIX THIS WHEN UNION TYPES APPEAR!
3408 // replace_in_map( obj, res );
3409
3410 // Return final merged results
3411 set_control( _gvn.transform(region) );
3412 record_for_igvn(region);
3413
3414 return record_profiled_receiver_for_speculation(res);
3415 }
3416
3417 //------------------------------next_monitor-----------------------------------
3418 // What number should be given to the next monitor?
3419 int GraphKit::next_monitor() {
3420 int current = jvms()->monitor_depth()* C->sync_stack_slots();
3421 int next = current + C->sync_stack_slots();
3422 // Keep the toplevel high water mark current:
3423 if (C->fixed_slots() < next) C->set_fixed_slots(next);
3424 return current;
3425 }
3426
3427 //------------------------------insert_mem_bar---------------------------------
3428 // Memory barrier to avoid floating things around
3429 // The membar serves as a pinch point between both control and all memory slices.
3430 Node* GraphKit::insert_mem_bar(int opcode, Node* precedent) {
3431 MemBarNode* mb = MemBarNode::make(C, opcode, Compile::AliasIdxBot, precedent);
3432 mb->init_req(TypeFunc::Control, control());
3433 mb->init_req(TypeFunc::Memory, reset_memory());
3434 Node* membar = _gvn.transform(mb);
3435 set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control)));
3436 set_all_memory_call(membar);
3437 return membar;
3438 }
3439
3440 //-------------------------insert_mem_bar_volatile----------------------------
3441 // Memory barrier to avoid floating things around
3442 // The membar serves as a pinch point between both control and memory(alias_idx).
3443 // If you want to make a pinch point on all memory slices, do not use this
3444 // function (even with AliasIdxBot); use insert_mem_bar() instead.
3445 Node* GraphKit::insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent) {
3446 // When Parse::do_put_xxx updates a volatile field, it appends a series
3447 // of MemBarVolatile nodes, one for *each* volatile field alias category.
3448 // The first membar is on the same memory slice as the field store opcode.
3449 // This forces the membar to follow the store. (Bug 6500685 broke this.)
3450 // All the other membars (for other volatile slices, including AliasIdxBot,
3451 // which stands for all unknown volatile slices) are control-dependent
3452 // on the first membar. This prevents later volatile loads or stores
3453 // from sliding up past the just-emitted store.
3454
3455 MemBarNode* mb = MemBarNode::make(C, opcode, alias_idx, precedent);
3456 mb->set_req(TypeFunc::Control,control());
3457 if (alias_idx == Compile::AliasIdxBot) {
3458 mb->set_req(TypeFunc::Memory, merged_memory()->base_memory());
3459 } else {
3460 assert(!(opcode == Op_Initialize && alias_idx != Compile::AliasIdxRaw), "fix caller");
3461 mb->set_req(TypeFunc::Memory, memory(alias_idx));
3462 }
3463 Node* membar = _gvn.transform(mb);
3464 set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control)));
3465 if (alias_idx == Compile::AliasIdxBot) {
3466 merged_memory()->set_base_memory(_gvn.transform(new ProjNode(membar, TypeFunc::Memory)));
3467 } else {
3468 set_memory(_gvn.transform(new ProjNode(membar, TypeFunc::Memory)),alias_idx);
3469 }
3470 return membar;
3471 }
3472
3473 //------------------------------shared_lock------------------------------------
3474 // Emit locking code.
3475 FastLockNode* GraphKit::shared_lock(Node* obj) {
3476 // bci is either a monitorenter bc or InvocationEntryBci
3477 // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3478 assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3479
3480 if( !GenerateSynchronizationCode )
3481 return nullptr; // Not locking things?
3482 if (stopped()) // Dead monitor?
3483 return nullptr;
3484
3485 assert(dead_locals_are_killed(), "should kill locals before sync. point");
3486
3487 // Box the stack location
3488 Node* box = new BoxLockNode(next_monitor());
3489 // Check for bailout after new BoxLockNode
3490 if (failing()) { return nullptr; }
3491 box = _gvn.transform(box);
3492 Node* mem = reset_memory();
3493
3494 FastLockNode * flock = _gvn.transform(new FastLockNode(nullptr, obj, box) )->as_FastLock();
3495
3496 // Add monitor to debug info for the slow path. If we block inside the
3497 // slow path and de-opt, we need the monitor hanging around
3498 map()->push_monitor( flock );
3499
3500 const TypeFunc *tf = LockNode::lock_type();
3501 LockNode *lock = new LockNode(C, tf);
3502
3503 lock->init_req( TypeFunc::Control, control() );
3504 lock->init_req( TypeFunc::Memory , mem );
3505 lock->init_req( TypeFunc::I_O , top() ) ; // does no i/o
3506 lock->init_req( TypeFunc::FramePtr, frameptr() );
3507 lock->init_req( TypeFunc::ReturnAdr, top() );
3508
3509 lock->init_req(TypeFunc::Parms + 0, obj);
3510 lock->init_req(TypeFunc::Parms + 1, box);
3511 lock->init_req(TypeFunc::Parms + 2, flock);
3512 add_safepoint_edges(lock);
3513
3514 lock = _gvn.transform( lock )->as_Lock();
3515
3516 // lock has no side-effects, sets few values
3517 set_predefined_output_for_runtime_call(lock, mem, TypeRawPtr::BOTTOM);
3518
3519 insert_mem_bar(Op_MemBarAcquireLock);
3520
3521 // Add this to the worklist so that the lock can be eliminated
3522 record_for_igvn(lock);
3523
3524 #ifndef PRODUCT
3525 if (PrintLockStatistics) {
3526 // Update the counter for this lock. Don't bother using an atomic
3527 // operation since we don't require absolute accuracy.
3528 lock->create_lock_counter(map()->jvms());
3529 increment_counter(lock->counter()->addr());
3530 }
3531 #endif
3532
3533 return flock;
3534 }
3535
3536
3537 //------------------------------shared_unlock----------------------------------
3538 // Emit unlocking code.
3539 void GraphKit::shared_unlock(Node* box, Node* obj) {
3540 // bci is either a monitorenter bc or InvocationEntryBci
3541 // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3542 assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3543
3544 if( !GenerateSynchronizationCode )
3545 return;
3546 if (stopped()) { // Dead monitor?
3547 map()->pop_monitor(); // Kill monitor from debug info
3548 return;
3549 }
3550
3551 // Memory barrier to avoid floating things down past the locked region
3552 insert_mem_bar(Op_MemBarReleaseLock);
3553
3554 const TypeFunc *tf = OptoRuntime::complete_monitor_exit_Type();
3555 UnlockNode *unlock = new UnlockNode(C, tf);
3556 #ifdef ASSERT
3557 unlock->set_dbg_jvms(sync_jvms());
3558 #endif
3559 uint raw_idx = Compile::AliasIdxRaw;
3560 unlock->init_req( TypeFunc::Control, control() );
3561 unlock->init_req( TypeFunc::Memory , memory(raw_idx) );
3562 unlock->init_req( TypeFunc::I_O , top() ) ; // does no i/o
3563 unlock->init_req( TypeFunc::FramePtr, frameptr() );
3564 unlock->init_req( TypeFunc::ReturnAdr, top() );
3565
3566 unlock->init_req(TypeFunc::Parms + 0, obj);
3567 unlock->init_req(TypeFunc::Parms + 1, box);
3568 unlock = _gvn.transform(unlock)->as_Unlock();
3569
3570 Node* mem = reset_memory();
3571
3572 // unlock has no side-effects, sets few values
3573 set_predefined_output_for_runtime_call(unlock, mem, TypeRawPtr::BOTTOM);
3574
3575 // Kill monitor from debug info
3576 map()->pop_monitor( );
3577 }
3578
3579 //-------------------------------get_layout_helper-----------------------------
3580 // If the given klass is a constant or known to be an array,
3581 // fetch the constant layout helper value into constant_value
3582 // and return null. Otherwise, load the non-constant
3583 // layout helper value, and return the node which represents it.
3584 // This two-faced routine is useful because allocation sites
3585 // almost always feature constant types.
3586 Node* GraphKit::get_layout_helper(Node* klass_node, jint& constant_value) {
3587 const TypeKlassPtr* klass_t = _gvn.type(klass_node)->isa_klassptr();
3588 if (!StressReflectiveCode && klass_t != nullptr) {
3589 bool xklass = klass_t->klass_is_exact();
3590 if (xklass || (klass_t->isa_aryklassptr() && klass_t->is_aryklassptr()->elem() != Type::BOTTOM)) {
3591 jint lhelper;
3592 if (klass_t->isa_aryklassptr()) {
3593 BasicType elem = klass_t->as_instance_type()->isa_aryptr()->elem()->array_element_basic_type();
3594 if (is_reference_type(elem, true)) {
3595 elem = T_OBJECT;
3596 }
3597 lhelper = Klass::array_layout_helper(elem);
3598 } else {
3599 lhelper = klass_t->is_instklassptr()->exact_klass()->layout_helper();
3600 }
3601 if (lhelper != Klass::_lh_neutral_value) {
3602 constant_value = lhelper;
3603 return (Node*) nullptr;
3604 }
3605 }
3606 }
3607 constant_value = Klass::_lh_neutral_value; // put in a known value
3608 Node* lhp = basic_plus_adr(klass_node, klass_node, in_bytes(Klass::layout_helper_offset()));
3609 return make_load(nullptr, lhp, TypeInt::INT, T_INT, MemNode::unordered);
3610 }
3611
3612 // We just put in an allocate/initialize with a big raw-memory effect.
3613 // Hook selected additional alias categories on the initialization.
3614 static void hook_memory_on_init(GraphKit& kit, int alias_idx,
3615 MergeMemNode* init_in_merge,
3616 Node* init_out_raw) {
3617 DEBUG_ONLY(Node* init_in_raw = init_in_merge->base_memory());
3618 assert(init_in_merge->memory_at(alias_idx) == init_in_raw, "");
3619
3620 Node* prevmem = kit.memory(alias_idx);
3621 init_in_merge->set_memory_at(alias_idx, prevmem);
3622 kit.set_memory(init_out_raw, alias_idx);
3623 }
3624
3625 //---------------------------set_output_for_allocation-------------------------
3626 Node* GraphKit::set_output_for_allocation(AllocateNode* alloc,
3627 const TypeOopPtr* oop_type,
3628 bool deoptimize_on_exception) {
3629 int rawidx = Compile::AliasIdxRaw;
3630 alloc->set_req( TypeFunc::FramePtr, frameptr() );
3631 add_safepoint_edges(alloc);
3632 Node* allocx = _gvn.transform(alloc);
3633 set_control( _gvn.transform(new ProjNode(allocx, TypeFunc::Control) ) );
3634 // create memory projection for i_o
3635 set_memory ( _gvn.transform( new ProjNode(allocx, TypeFunc::Memory, true) ), rawidx );
3636 make_slow_call_ex(allocx, env()->Throwable_klass(), true, deoptimize_on_exception);
3637
3638 // create a memory projection as for the normal control path
3639 Node* malloc = _gvn.transform(new ProjNode(allocx, TypeFunc::Memory));
3640 set_memory(malloc, rawidx);
3641
3642 // a normal slow-call doesn't change i_o, but an allocation does
3643 // we create a separate i_o projection for the normal control path
3644 set_i_o(_gvn.transform( new ProjNode(allocx, TypeFunc::I_O, false) ) );
3645 Node* rawoop = _gvn.transform( new ProjNode(allocx, TypeFunc::Parms) );
3646
3647 // put in an initialization barrier
3648 InitializeNode* init = insert_mem_bar_volatile(Op_Initialize, rawidx,
3649 rawoop)->as_Initialize();
3650 assert(alloc->initialization() == init, "2-way macro link must work");
3651 assert(init ->allocation() == alloc, "2-way macro link must work");
3652 {
3653 // Extract memory strands which may participate in the new object's
3654 // initialization, and source them from the new InitializeNode.
3655 // This will allow us to observe initializations when they occur,
3656 // and link them properly (as a group) to the InitializeNode.
3657 assert(init->in(InitializeNode::Memory) == malloc, "");
3658 MergeMemNode* minit_in = MergeMemNode::make(malloc);
3659 init->set_req(InitializeNode::Memory, minit_in);
3660 record_for_igvn(minit_in); // fold it up later, if possible
3661 Node* minit_out = memory(rawidx);
3662 assert(minit_out->is_Proj() && minit_out->in(0) == init, "");
3663 // Add an edge in the MergeMem for the header fields so an access
3664 // to one of those has correct memory state
3665 set_memory(minit_out, C->get_alias_index(oop_type->add_offset(oopDesc::mark_offset_in_bytes())));
3666 set_memory(minit_out, C->get_alias_index(oop_type->add_offset(oopDesc::klass_offset_in_bytes())));
3667 if (oop_type->isa_aryptr()) {
3668 const TypePtr* telemref = oop_type->add_offset(Type::OffsetBot);
3669 int elemidx = C->get_alias_index(telemref);
3670 hook_memory_on_init(*this, elemidx, minit_in, minit_out);
3671 } else if (oop_type->isa_instptr()) {
3672 ciInstanceKlass* ik = oop_type->is_instptr()->instance_klass();
3673 for (int i = 0, len = ik->nof_nonstatic_fields(); i < len; i++) {
3674 ciField* field = ik->nonstatic_field_at(i);
3675 if (field->offset_in_bytes() >= TrackedInitializationLimit * HeapWordSize)
3676 continue; // do not bother to track really large numbers of fields
3677 // Find (or create) the alias category for this field:
3678 int fieldidx = C->alias_type(field)->index();
3679 hook_memory_on_init(*this, fieldidx, minit_in, minit_out);
3680 }
3681 }
3682 }
3683
3684 // Cast raw oop to the real thing...
3685 Node* javaoop = new CheckCastPPNode(control(), rawoop, oop_type);
3686 javaoop = _gvn.transform(javaoop);
3687 C->set_recent_alloc(control(), javaoop);
3688 assert(just_allocated_object(control()) == javaoop, "just allocated");
3689
3690 #ifdef ASSERT
3691 { // Verify that the AllocateNode::Ideal_allocation recognizers work:
3692 assert(AllocateNode::Ideal_allocation(rawoop) == alloc,
3693 "Ideal_allocation works");
3694 assert(AllocateNode::Ideal_allocation(javaoop) == alloc,
3695 "Ideal_allocation works");
3696 if (alloc->is_AllocateArray()) {
3697 assert(AllocateArrayNode::Ideal_array_allocation(rawoop) == alloc->as_AllocateArray(),
3698 "Ideal_allocation works");
3699 assert(AllocateArrayNode::Ideal_array_allocation(javaoop) == alloc->as_AllocateArray(),
3700 "Ideal_allocation works");
3701 } else {
3702 assert(alloc->in(AllocateNode::ALength)->is_top(), "no length, please");
3703 }
3704 }
3705 #endif //ASSERT
3706
3707 return javaoop;
3708 }
3709
3710 //---------------------------new_instance--------------------------------------
3711 // This routine takes a klass_node which may be constant (for a static type)
3712 // or may be non-constant (for reflective code). It will work equally well
3713 // for either, and the graph will fold nicely if the optimizer later reduces
3714 // the type to a constant.
3715 // The optional arguments are for specialized use by intrinsics:
3716 // - If 'extra_slow_test' if not null is an extra condition for the slow-path.
3717 // - If 'return_size_val', report the total object size to the caller.
3718 // - deoptimize_on_exception controls how Java exceptions are handled (rethrow vs deoptimize)
3719 Node* GraphKit::new_instance(Node* klass_node,
3720 Node* extra_slow_test,
3721 Node* *return_size_val,
3722 bool deoptimize_on_exception) {
3723 // Compute size in doublewords
3724 // The size is always an integral number of doublewords, represented
3725 // as a positive bytewise size stored in the klass's layout_helper.
3726 // The layout_helper also encodes (in a low bit) the need for a slow path.
3727 jint layout_con = Klass::_lh_neutral_value;
3728 Node* layout_val = get_layout_helper(klass_node, layout_con);
3729 int layout_is_con = (layout_val == nullptr);
3730
3731 if (extra_slow_test == nullptr) extra_slow_test = intcon(0);
3732 // Generate the initial go-slow test. It's either ALWAYS (return a
3733 // Node for 1) or NEVER (return a null) or perhaps (in the reflective
3734 // case) a computed value derived from the layout_helper.
3735 Node* initial_slow_test = nullptr;
3736 if (layout_is_con) {
3737 assert(!StressReflectiveCode, "stress mode does not use these paths");
3738 bool must_go_slow = Klass::layout_helper_needs_slow_path(layout_con);
3739 initial_slow_test = must_go_slow ? intcon(1) : extra_slow_test;
3740 } else { // reflective case
3741 // This reflective path is used by Unsafe.allocateInstance.
3742 // (It may be stress-tested by specifying StressReflectiveCode.)
3743 // Basically, we want to get into the VM is there's an illegal argument.
3744 Node* bit = intcon(Klass::_lh_instance_slow_path_bit);
3745 initial_slow_test = _gvn.transform( new AndINode(layout_val, bit) );
3746 if (extra_slow_test != intcon(0)) {
3747 initial_slow_test = _gvn.transform( new OrINode(initial_slow_test, extra_slow_test) );
3748 }
3749 // (Macro-expander will further convert this to a Bool, if necessary.)
3750 }
3751
3752 // Find the size in bytes. This is easy; it's the layout_helper.
3753 // The size value must be valid even if the slow path is taken.
3754 Node* size = nullptr;
3755 if (layout_is_con) {
3756 size = MakeConX(Klass::layout_helper_size_in_bytes(layout_con));
3757 } else { // reflective case
3758 // This reflective path is used by clone and Unsafe.allocateInstance.
3759 size = ConvI2X(layout_val);
3760
3761 // Clear the low bits to extract layout_helper_size_in_bytes:
3762 assert((int)Klass::_lh_instance_slow_path_bit < BytesPerLong, "clear bit");
3763 Node* mask = MakeConX(~ (intptr_t)right_n_bits(LogBytesPerLong));
3764 size = _gvn.transform( new AndXNode(size, mask) );
3765 }
3766 if (return_size_val != nullptr) {
3767 (*return_size_val) = size;
3768 }
3769
3770 // This is a precise notnull oop of the klass.
3771 // (Actually, it need not be precise if this is a reflective allocation.)
3772 // It's what we cast the result to.
3773 const TypeKlassPtr* tklass = _gvn.type(klass_node)->isa_klassptr();
3774 if (!tklass) tklass = TypeInstKlassPtr::OBJECT;
3775 const TypeOopPtr* oop_type = tklass->as_instance_type();
3776
3777 // Now generate allocation code
3778
3779 // The entire memory state is needed for slow path of the allocation
3780 // since GC and deoptimization can happened.
3781 Node *mem = reset_memory();
3782 set_all_memory(mem); // Create new memory state
3783
3784 AllocateNode* alloc = new AllocateNode(C, AllocateNode::alloc_type(Type::TOP),
3785 control(), mem, i_o(),
3786 size, klass_node,
3787 initial_slow_test);
3788
3789 return set_output_for_allocation(alloc, oop_type, deoptimize_on_exception);
3790 }
3791
3792 //-------------------------------new_array-------------------------------------
3793 // helper for both newarray and anewarray
3794 // The 'length' parameter is (obviously) the length of the array.
3795 // The optional arguments are for specialized use by intrinsics:
3796 // - If 'return_size_val', report the non-padded array size (sum of header size
3797 // and array body) to the caller.
3798 // - deoptimize_on_exception controls how Java exceptions are handled (rethrow vs deoptimize)
3799 Node* GraphKit::new_array(Node* klass_node, // array klass (maybe variable)
3800 Node* length, // number of array elements
3801 int nargs, // number of arguments to push back for uncommon trap
3802 Node* *return_size_val,
3803 bool deoptimize_on_exception) {
3804 jint layout_con = Klass::_lh_neutral_value;
3805 Node* layout_val = get_layout_helper(klass_node, layout_con);
3806 int layout_is_con = (layout_val == nullptr);
3807
3808 if (!layout_is_con && !StressReflectiveCode &&
3809 !too_many_traps(Deoptimization::Reason_class_check)) {
3810 // This is a reflective array creation site.
3811 // Optimistically assume that it is a subtype of Object[],
3812 // so that we can fold up all the address arithmetic.
3813 layout_con = Klass::array_layout_helper(T_OBJECT);
3814 Node* cmp_lh = _gvn.transform( new CmpINode(layout_val, intcon(layout_con)) );
3815 Node* bol_lh = _gvn.transform( new BoolNode(cmp_lh, BoolTest::eq) );
3816 { BuildCutout unless(this, bol_lh, PROB_MAX);
3817 inc_sp(nargs);
3818 uncommon_trap(Deoptimization::Reason_class_check,
3819 Deoptimization::Action_maybe_recompile);
3820 }
3821 layout_val = nullptr;
3822 layout_is_con = true;
3823 }
3824
3825 // Generate the initial go-slow test. Make sure we do not overflow
3826 // if length is huge (near 2Gig) or negative! We do not need
3827 // exact double-words here, just a close approximation of needed
3828 // double-words. We can't add any offset or rounding bits, lest we
3829 // take a size -1 of bytes and make it positive. Use an unsigned
3830 // compare, so negative sizes look hugely positive.
3831 int fast_size_limit = FastAllocateSizeLimit;
3832 if (layout_is_con) {
3833 assert(!StressReflectiveCode, "stress mode does not use these paths");
3834 // Increase the size limit if we have exact knowledge of array type.
3835 int log2_esize = Klass::layout_helper_log2_element_size(layout_con);
3836 fast_size_limit <<= (LogBytesPerLong - log2_esize);
3837 }
3838
3839 Node* initial_slow_cmp = _gvn.transform( new CmpUNode( length, intcon( fast_size_limit ) ) );
3840 Node* initial_slow_test = _gvn.transform( new BoolNode( initial_slow_cmp, BoolTest::gt ) );
3841
3842 // --- Size Computation ---
3843 // array_size = round_to_heap(array_header + (length << elem_shift));
3844 // where round_to_heap(x) == align_to(x, MinObjAlignmentInBytes)
3845 // and align_to(x, y) == ((x + y-1) & ~(y-1))
3846 // The rounding mask is strength-reduced, if possible.
3847 int round_mask = MinObjAlignmentInBytes - 1;
3848 Node* header_size = nullptr;
3849 // (T_BYTE has the weakest alignment and size restrictions...)
3850 if (layout_is_con) {
3851 int hsize = Klass::layout_helper_header_size(layout_con);
3852 int eshift = Klass::layout_helper_log2_element_size(layout_con);
3853 if ((round_mask & ~right_n_bits(eshift)) == 0)
3854 round_mask = 0; // strength-reduce it if it goes away completely
3855 assert((hsize & right_n_bits(eshift)) == 0, "hsize is pre-rounded");
3856 int header_size_min = arrayOopDesc::base_offset_in_bytes(T_BYTE);
3857 assert(header_size_min <= hsize, "generic minimum is smallest");
3858 header_size = intcon(hsize);
3859 } else {
3860 Node* hss = intcon(Klass::_lh_header_size_shift);
3861 Node* hsm = intcon(Klass::_lh_header_size_mask);
3862 header_size = _gvn.transform(new URShiftINode(layout_val, hss));
3863 header_size = _gvn.transform(new AndINode(header_size, hsm));
3864 }
3865
3866 Node* elem_shift = nullptr;
3867 if (layout_is_con) {
3868 int eshift = Klass::layout_helper_log2_element_size(layout_con);
3869 if (eshift != 0)
3870 elem_shift = intcon(eshift);
3871 } else {
3872 // There is no need to mask or shift this value.
3873 // The semantics of LShiftINode include an implicit mask to 0x1F.
3874 assert(Klass::_lh_log2_element_size_shift == 0, "use shift in place");
3875 elem_shift = layout_val;
3876 }
3877
3878 // Transition to native address size for all offset calculations:
3879 Node* lengthx = ConvI2X(length);
3880 Node* headerx = ConvI2X(header_size);
3881 #ifdef _LP64
3882 { const TypeInt* tilen = _gvn.find_int_type(length);
3883 if (tilen != nullptr && tilen->_lo < 0) {
3884 // Add a manual constraint to a positive range. Cf. array_element_address.
3885 jint size_max = fast_size_limit;
3886 if (size_max > tilen->_hi) size_max = tilen->_hi;
3887 const TypeInt* tlcon = TypeInt::make(0, size_max, Type::WidenMin);
3888
3889 // Only do a narrow I2L conversion if the range check passed.
3890 IfNode* iff = new IfNode(control(), initial_slow_test, PROB_MIN, COUNT_UNKNOWN);
3891 _gvn.transform(iff);
3892 RegionNode* region = new RegionNode(3);
3893 _gvn.set_type(region, Type::CONTROL);
3894 lengthx = new PhiNode(region, TypeLong::LONG);
3895 _gvn.set_type(lengthx, TypeLong::LONG);
3896
3897 // Range check passed. Use ConvI2L node with narrow type.
3898 Node* passed = IfFalse(iff);
3899 region->init_req(1, passed);
3900 // Make I2L conversion control dependent to prevent it from
3901 // floating above the range check during loop optimizations.
3902 lengthx->init_req(1, C->constrained_convI2L(&_gvn, length, tlcon, passed));
3903
3904 // Range check failed. Use ConvI2L with wide type because length may be invalid.
3905 region->init_req(2, IfTrue(iff));
3906 lengthx->init_req(2, ConvI2X(length));
3907
3908 set_control(region);
3909 record_for_igvn(region);
3910 record_for_igvn(lengthx);
3911 }
3912 }
3913 #endif
3914
3915 // Combine header size and body size for the array copy part, then align (if
3916 // necessary) for the allocation part. This computation cannot overflow,
3917 // because it is used only in two places, one where the length is sharply
3918 // limited, and the other after a successful allocation.
3919 Node* abody = lengthx;
3920 if (elem_shift != nullptr) {
3921 abody = _gvn.transform(new LShiftXNode(lengthx, elem_shift));
3922 }
3923 Node* non_rounded_size = _gvn.transform(new AddXNode(headerx, abody));
3924
3925 if (return_size_val != nullptr) {
3926 // This is the size
3927 (*return_size_val) = non_rounded_size;
3928 }
3929
3930 Node* size = non_rounded_size;
3931 if (round_mask != 0) {
3932 Node* mask1 = MakeConX(round_mask);
3933 size = _gvn.transform(new AddXNode(size, mask1));
3934 Node* mask2 = MakeConX(~round_mask);
3935 size = _gvn.transform(new AndXNode(size, mask2));
3936 }
3937 // else if round_mask == 0, the size computation is self-rounding
3938
3939 // Now generate allocation code
3940
3941 // The entire memory state is needed for slow path of the allocation
3942 // since GC and deoptimization can happened.
3943 Node *mem = reset_memory();
3944 set_all_memory(mem); // Create new memory state
3945
3946 if (initial_slow_test->is_Bool()) {
3947 // Hide it behind a CMoveI, or else PhaseIdealLoop::split_up will get sick.
3948 initial_slow_test = initial_slow_test->as_Bool()->as_int_value(&_gvn);
3949 }
3950
3951 const TypeOopPtr* ary_type = _gvn.type(klass_node)->is_klassptr()->as_instance_type();
3952 Node* valid_length_test = _gvn.intcon(1);
3953 if (ary_type->isa_aryptr()) {
3954 BasicType bt = ary_type->isa_aryptr()->elem()->array_element_basic_type();
3955 jint max = TypeAryPtr::max_array_length(bt);
3956 Node* valid_length_cmp = _gvn.transform(new CmpUNode(length, intcon(max)));
3957 valid_length_test = _gvn.transform(new BoolNode(valid_length_cmp, BoolTest::le));
3958 }
3959
3960 // Create the AllocateArrayNode and its result projections
3961 AllocateArrayNode* alloc
3962 = new AllocateArrayNode(C, AllocateArrayNode::alloc_type(TypeInt::INT),
3963 control(), mem, i_o(),
3964 size, klass_node,
3965 initial_slow_test,
3966 length, valid_length_test);
3967
3968 // Cast to correct type. Note that the klass_node may be constant or not,
3969 // and in the latter case the actual array type will be inexact also.
3970 // (This happens via a non-constant argument to inline_native_newArray.)
3971 // In any case, the value of klass_node provides the desired array type.
3972 const TypeInt* length_type = _gvn.find_int_type(length);
3973 if (ary_type->isa_aryptr() && length_type != nullptr) {
3974 // Try to get a better type than POS for the size
3975 ary_type = ary_type->is_aryptr()->cast_to_size(length_type);
3976 }
3977
3978 Node* javaoop = set_output_for_allocation(alloc, ary_type, deoptimize_on_exception);
3979
3980 array_ideal_length(alloc, ary_type, true);
3981 return javaoop;
3982 }
3983
3984 // The following "Ideal_foo" functions are placed here because they recognize
3985 // the graph shapes created by the functions immediately above.
3986
3987 //---------------------------Ideal_allocation----------------------------------
3988 // Given an oop pointer or raw pointer, see if it feeds from an AllocateNode.
3989 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr) {
3990 if (ptr == nullptr) { // reduce dumb test in callers
3991 return nullptr;
3992 }
3993
3994 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
3995 ptr = bs->step_over_gc_barrier(ptr);
3996
3997 if (ptr->is_CheckCastPP()) { // strip only one raw-to-oop cast
3998 ptr = ptr->in(1);
3999 if (ptr == nullptr) return nullptr;
4000 }
4001 // Return null for allocations with several casts:
4002 // j.l.reflect.Array.newInstance(jobject, jint)
4003 // Object.clone()
4004 // to keep more precise type from last cast.
4005 if (ptr->is_Proj()) {
4006 Node* allo = ptr->in(0);
4007 if (allo != nullptr && allo->is_Allocate()) {
4008 return allo->as_Allocate();
4009 }
4010 }
4011 // Report failure to match.
4012 return nullptr;
4013 }
4014
4015 // Fancy version which also strips off an offset (and reports it to caller).
4016 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseValues* phase,
4017 intptr_t& offset) {
4018 Node* base = AddPNode::Ideal_base_and_offset(ptr, phase, offset);
4019 if (base == nullptr) return nullptr;
4020 return Ideal_allocation(base);
4021 }
4022
4023 // Trace Initialize <- Proj[Parm] <- Allocate
4024 AllocateNode* InitializeNode::allocation() {
4025 Node* rawoop = in(InitializeNode::RawAddress);
4026 if (rawoop->is_Proj()) {
4027 Node* alloc = rawoop->in(0);
4028 if (alloc->is_Allocate()) {
4029 return alloc->as_Allocate();
4030 }
4031 }
4032 return nullptr;
4033 }
4034
4035 // Trace Allocate -> Proj[Parm] -> Initialize
4036 InitializeNode* AllocateNode::initialization() {
4037 ProjNode* rawoop = proj_out_or_null(AllocateNode::RawAddress);
4038 if (rawoop == nullptr) return nullptr;
4039 for (DUIterator_Fast imax, i = rawoop->fast_outs(imax); i < imax; i++) {
4040 Node* init = rawoop->fast_out(i);
4041 if (init->is_Initialize()) {
4042 assert(init->as_Initialize()->allocation() == this, "2-way link");
4043 return init->as_Initialize();
4044 }
4045 }
4046 return nullptr;
4047 }
4048
4049 // Add a Parse Predicate with an uncommon trap on the failing/false path. Normal control will continue on the true path.
4050 void GraphKit::add_parse_predicate(Deoptimization::DeoptReason reason, const int nargs) {
4051 // Too many traps seen?
4052 if (too_many_traps(reason)) {
4053 #ifdef ASSERT
4054 if (TraceLoopPredicate) {
4055 int tc = C->trap_count(reason);
4056 tty->print("too many traps=%s tcount=%d in ",
4057 Deoptimization::trap_reason_name(reason), tc);
4058 method()->print(); // which method has too many predicate traps
4059 tty->cr();
4060 }
4061 #endif
4062 // We cannot afford to take more traps here,
4063 // do not generate Parse Predicate.
4064 return;
4065 }
4066
4067 ParsePredicateNode* parse_predicate = new ParsePredicateNode(control(), reason, &_gvn);
4068 _gvn.set_type(parse_predicate, parse_predicate->Value(&_gvn));
4069 Node* if_false = _gvn.transform(new IfFalseNode(parse_predicate));
4070 {
4071 PreserveJVMState pjvms(this);
4072 set_control(if_false);
4073 inc_sp(nargs);
4074 uncommon_trap(reason, Deoptimization::Action_maybe_recompile);
4075 }
4076 Node* if_true = _gvn.transform(new IfTrueNode(parse_predicate));
4077 set_control(if_true);
4078 }
4079
4080 // Add Parse Predicates which serve as placeholders to create new Runtime Predicates above them. All
4081 // Runtime Predicates inside a Runtime Predicate block share the same uncommon trap as the Parse Predicate.
4082 void GraphKit::add_parse_predicates(int nargs) {
4083 if (UseLoopPredicate) {
4084 add_parse_predicate(Deoptimization::Reason_predicate, nargs);
4085 }
4086 if (UseProfiledLoopPredicate) {
4087 add_parse_predicate(Deoptimization::Reason_profile_predicate, nargs);
4088 }
4089 // Loop Limit Check Predicate should be near the loop.
4090 add_parse_predicate(Deoptimization::Reason_loop_limit_check, nargs);
4091 }
4092
4093 void GraphKit::sync_kit(IdealKit& ideal) {
4094 set_all_memory(ideal.merged_memory());
4095 set_i_o(ideal.i_o());
4096 set_control(ideal.ctrl());
4097 }
4098
4099 void GraphKit::final_sync(IdealKit& ideal) {
4100 // Final sync IdealKit and graphKit.
4101 sync_kit(ideal);
4102 }
4103
4104 Node* GraphKit::load_String_length(Node* str, bool set_ctrl) {
4105 Node* len = load_array_length(load_String_value(str, set_ctrl));
4106 Node* coder = load_String_coder(str, set_ctrl);
4107 // Divide length by 2 if coder is UTF16
4108 return _gvn.transform(new RShiftINode(len, coder));
4109 }
4110
4111 Node* GraphKit::load_String_value(Node* str, bool set_ctrl) {
4112 int value_offset = java_lang_String::value_offset();
4113 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4114 false, nullptr, 0);
4115 const TypePtr* value_field_type = string_type->add_offset(value_offset);
4116 const TypeAryPtr* value_type = TypeAryPtr::make(TypePtr::NotNull,
4117 TypeAry::make(TypeInt::BYTE, TypeInt::POS),
4118 ciTypeArrayKlass::make(T_BYTE), true, 0);
4119 Node* p = basic_plus_adr(str, str, value_offset);
4120 Node* load = access_load_at(str, p, value_field_type, value_type, T_OBJECT,
4121 IN_HEAP | (set_ctrl ? C2_CONTROL_DEPENDENT_LOAD : 0) | MO_UNORDERED);
4122 return load;
4123 }
4124
4125 Node* GraphKit::load_String_coder(Node* str, bool set_ctrl) {
4126 if (!CompactStrings) {
4127 return intcon(java_lang_String::CODER_UTF16);
4128 }
4129 int coder_offset = java_lang_String::coder_offset();
4130 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4131 false, nullptr, 0);
4132 const TypePtr* coder_field_type = string_type->add_offset(coder_offset);
4133
4134 Node* p = basic_plus_adr(str, str, coder_offset);
4135 Node* load = access_load_at(str, p, coder_field_type, TypeInt::BYTE, T_BYTE,
4136 IN_HEAP | (set_ctrl ? C2_CONTROL_DEPENDENT_LOAD : 0) | MO_UNORDERED);
4137 return load;
4138 }
4139
4140 void GraphKit::store_String_value(Node* str, Node* value) {
4141 int value_offset = java_lang_String::value_offset();
4142 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4143 false, nullptr, 0);
4144 const TypePtr* value_field_type = string_type->add_offset(value_offset);
4145
4146 access_store_at(str, basic_plus_adr(str, value_offset), value_field_type,
4147 value, TypeAryPtr::BYTES, T_OBJECT, IN_HEAP | MO_UNORDERED);
4148 }
4149
4150 void GraphKit::store_String_coder(Node* str, Node* value) {
4151 int coder_offset = java_lang_String::coder_offset();
4152 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4153 false, nullptr, 0);
4154 const TypePtr* coder_field_type = string_type->add_offset(coder_offset);
4155
4156 access_store_at(str, basic_plus_adr(str, coder_offset), coder_field_type,
4157 value, TypeInt::BYTE, T_BYTE, IN_HEAP | MO_UNORDERED);
4158 }
4159
4160 // Capture src and dst memory state with a MergeMemNode
4161 Node* GraphKit::capture_memory(const TypePtr* src_type, const TypePtr* dst_type) {
4162 if (src_type == dst_type) {
4163 // Types are equal, we don't need a MergeMemNode
4164 return memory(src_type);
4165 }
4166 MergeMemNode* merge = MergeMemNode::make(map()->memory());
4167 record_for_igvn(merge); // fold it up later, if possible
4168 int src_idx = C->get_alias_index(src_type);
4169 int dst_idx = C->get_alias_index(dst_type);
4170 merge->set_memory_at(src_idx, memory(src_idx));
4171 merge->set_memory_at(dst_idx, memory(dst_idx));
4172 return merge;
4173 }
4174
4175 Node* GraphKit::compress_string(Node* src, const TypeAryPtr* src_type, Node* dst, Node* count) {
4176 assert(Matcher::match_rule_supported(Op_StrCompressedCopy), "Intrinsic not supported");
4177 assert(src_type == TypeAryPtr::BYTES || src_type == TypeAryPtr::CHARS, "invalid source type");
4178 // If input and output memory types differ, capture both states to preserve
4179 // the dependency between preceding and subsequent loads/stores.
4180 // For example, the following program:
4181 // StoreB
4182 // compress_string
4183 // LoadB
4184 // has this memory graph (use->def):
4185 // LoadB -> compress_string -> CharMem
4186 // ... -> StoreB -> ByteMem
4187 // The intrinsic hides the dependency between LoadB and StoreB, causing
4188 // the load to read from memory not containing the result of the StoreB.
4189 // The correct memory graph should look like this:
4190 // LoadB -> compress_string -> MergeMem(CharMem, StoreB(ByteMem))
4191 Node* mem = capture_memory(src_type, TypeAryPtr::BYTES);
4192 StrCompressedCopyNode* str = new StrCompressedCopyNode(control(), mem, src, dst, count);
4193 Node* res_mem = _gvn.transform(new SCMemProjNode(_gvn.transform(str)));
4194 set_memory(res_mem, TypeAryPtr::BYTES);
4195 return str;
4196 }
4197
4198 void GraphKit::inflate_string(Node* src, Node* dst, const TypeAryPtr* dst_type, Node* count) {
4199 assert(Matcher::match_rule_supported(Op_StrInflatedCopy), "Intrinsic not supported");
4200 assert(dst_type == TypeAryPtr::BYTES || dst_type == TypeAryPtr::CHARS, "invalid dest type");
4201 // Capture src and dst memory (see comment in 'compress_string').
4202 Node* mem = capture_memory(TypeAryPtr::BYTES, dst_type);
4203 StrInflatedCopyNode* str = new StrInflatedCopyNode(control(), mem, src, dst, count);
4204 set_memory(_gvn.transform(str), dst_type);
4205 }
4206
4207 void GraphKit::inflate_string_slow(Node* src, Node* dst, Node* start, Node* count) {
4208 /**
4209 * int i_char = start;
4210 * for (int i_byte = 0; i_byte < count; i_byte++) {
4211 * dst[i_char++] = (char)(src[i_byte] & 0xff);
4212 * }
4213 */
4214 add_parse_predicates();
4215 C->set_has_loops(true);
4216
4217 RegionNode* head = new RegionNode(3);
4218 head->init_req(1, control());
4219 gvn().set_type(head, Type::CONTROL);
4220 record_for_igvn(head);
4221
4222 Node* i_byte = new PhiNode(head, TypeInt::INT);
4223 i_byte->init_req(1, intcon(0));
4224 gvn().set_type(i_byte, TypeInt::INT);
4225 record_for_igvn(i_byte);
4226
4227 Node* i_char = new PhiNode(head, TypeInt::INT);
4228 i_char->init_req(1, start);
4229 gvn().set_type(i_char, TypeInt::INT);
4230 record_for_igvn(i_char);
4231
4232 Node* mem = PhiNode::make(head, memory(TypeAryPtr::BYTES), Type::MEMORY, TypeAryPtr::BYTES);
4233 gvn().set_type(mem, Type::MEMORY);
4234 record_for_igvn(mem);
4235 set_control(head);
4236 set_memory(mem, TypeAryPtr::BYTES);
4237 Node* ch = load_array_element(src, i_byte, TypeAryPtr::BYTES, /* set_ctrl */ true);
4238 Node* st = store_to_memory(control(), array_element_address(dst, i_char, T_BYTE),
4239 AndI(ch, intcon(0xff)), T_CHAR, MemNode::unordered, false,
4240 false, true /* mismatched */);
4241
4242 IfNode* iff = create_and_map_if(head, Bool(CmpI(i_byte, count), BoolTest::lt), PROB_FAIR, COUNT_UNKNOWN);
4243 head->init_req(2, IfTrue(iff));
4244 mem->init_req(2, st);
4245 i_byte->init_req(2, AddI(i_byte, intcon(1)));
4246 i_char->init_req(2, AddI(i_char, intcon(2)));
4247
4248 set_control(IfFalse(iff));
4249 set_memory(st, TypeAryPtr::BYTES);
4250 }
4251
4252 Node* GraphKit::make_constant_from_field(ciField* field, Node* obj) {
4253 if (!field->is_constant()) {
4254 return nullptr; // Field not marked as constant.
4255 }
4256 ciInstance* holder = nullptr;
4257 if (!field->is_static()) {
4258 ciObject* const_oop = obj->bottom_type()->is_oopptr()->const_oop();
4259 if (const_oop != nullptr && const_oop->is_instance()) {
4260 holder = const_oop->as_instance();
4261 }
4262 }
4263 const Type* con_type = Type::make_constant_from_field(field, holder, field->layout_type(),
4264 /*is_unsigned_load=*/false);
4265 if (con_type != nullptr) {
4266 return makecon(con_type);
4267 }
4268 return nullptr;
4269 }
4270
4271 Node* GraphKit::maybe_narrow_object_type(Node* obj, ciKlass* type) {
4272 const TypeOopPtr* obj_type = obj->bottom_type()->isa_oopptr();
4273 const TypeOopPtr* sig_type = TypeOopPtr::make_from_klass(type);
4274 if (obj_type != nullptr && sig_type->is_loaded() && !obj_type->higher_equal(sig_type)) {
4275 const Type* narrow_obj_type = obj_type->filter_speculative(sig_type); // keep speculative part
4276 Node* casted_obj = gvn().transform(new CheckCastPPNode(control(), obj, narrow_obj_type));
4277 return casted_obj;
4278 }
4279 return obj;
4280 }