1 /*
2 * Copyright (c) 2001, 2026, 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 "asm/register.hpp"
26 #include "ci/ciObjArray.hpp"
27 #include "ci/ciUtilities.hpp"
28 #include "classfile/javaClasses.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/reachability.hpp"
45 #include "opto/rootnode.hpp"
46 #include "opto/runtime.hpp"
47 #include "opto/subtypenode.hpp"
48 #include "runtime/deoptimization.hpp"
49 #include "runtime/sharedRuntime.hpp"
50 #include "utilities/bitMap.inline.hpp"
51 #include "utilities/growableArray.hpp"
52 #include "utilities/powerOfTwo.hpp"
53
54 //----------------------------GraphKit-----------------------------------------
55 // Main utility constructor.
56 GraphKit::GraphKit(JVMState* jvms)
57 : Phase(Phase::Parser),
58 _env(C->env()),
59 _gvn(*C->initial_gvn()),
60 _barrier_set(BarrierSet::barrier_set()->barrier_set_c2())
61 {
62 _exceptions = jvms->map()->next_exception();
63 if (_exceptions != nullptr) jvms->map()->set_next_exception(nullptr);
64 set_jvms(jvms);
65 }
66
67 // Private constructor for parser.
68 GraphKit::GraphKit()
69 : Phase(Phase::Parser),
70 _env(C->env()),
71 _gvn(*C->initial_gvn()),
72 _barrier_set(BarrierSet::barrier_set()->barrier_set_c2())
73 {
74 _exceptions = nullptr;
75 set_map(nullptr);
76 DEBUG_ONLY(_sp = -99);
77 DEBUG_ONLY(set_bci(-99));
78 }
79
80
81
82 //---------------------------clean_stack---------------------------------------
83 // Clear away rubbish from the stack area of the JVM state.
84 // This destroys any arguments that may be waiting on the stack.
85 void GraphKit::clean_stack(int from_sp) {
86 SafePointNode* map = this->map();
87 JVMState* jvms = this->jvms();
88 int stk_size = jvms->stk_size();
89 int stkoff = jvms->stkoff();
90 Node* top = this->top();
91 for (int i = from_sp; i < stk_size; i++) {
92 if (map->in(stkoff + i) != top) {
93 map->set_req(stkoff + i, top);
94 }
95 }
96 }
97
98
99 //--------------------------------sync_jvms-----------------------------------
100 // Make sure our current jvms agrees with our parse state.
101 JVMState* GraphKit::sync_jvms() const {
102 JVMState* jvms = this->jvms();
103 jvms->set_bci(bci()); // Record the new bci in the JVMState
104 jvms->set_sp(sp()); // Record the new sp in the JVMState
105 assert(jvms_in_sync(), "jvms is now in sync");
106 return jvms;
107 }
108
109 //--------------------------------sync_jvms_for_reexecute---------------------
110 // Make sure our current jvms agrees with our parse state. This version
111 // uses the reexecute_sp for reexecuting bytecodes.
112 JVMState* GraphKit::sync_jvms_for_reexecute() {
113 JVMState* jvms = this->jvms();
114 jvms->set_bci(bci()); // Record the new bci in the JVMState
115 jvms->set_sp(reexecute_sp()); // Record the new sp in the JVMState
116 return jvms;
117 }
118
119 #ifdef ASSERT
120 bool GraphKit::jvms_in_sync() const {
121 Parse* parse = is_Parse();
122 if (parse == nullptr) {
123 if (bci() != jvms()->bci()) return false;
124 if (sp() != (int)jvms()->sp()) return false;
125 return true;
126 }
127 if (jvms()->method() != parse->method()) return false;
128 if (jvms()->bci() != parse->bci()) return false;
129 int jvms_sp = jvms()->sp();
130 if (jvms_sp != parse->sp()) return false;
131 int jvms_depth = jvms()->depth();
132 if (jvms_depth != parse->depth()) return false;
133 return true;
134 }
135
136 // Local helper checks for special internal merge points
137 // used to accumulate and merge exception states.
138 // They are marked by the region's in(0) edge being the map itself.
139 // Such merge points must never "escape" into the parser at large,
140 // until they have been handed to gvn.transform.
141 static bool is_hidden_merge(Node* reg) {
142 if (reg == nullptr) return false;
143 if (reg->is_Phi()) {
144 reg = reg->in(0);
145 if (reg == nullptr) return false;
146 }
147 return reg->is_Region() && reg->in(0) != nullptr && reg->in(0)->is_Root();
148 }
149
150 void GraphKit::verify_map() const {
151 if (map() == nullptr) return; // null map is OK
152 assert(map()->req() <= jvms()->endoff(), "no extra garbage on map");
153 assert(!map()->has_exceptions(), "call add_exception_states_from 1st");
154 assert(!is_hidden_merge(control()), "call use_exception_state, not set_map");
155 }
156
157 void GraphKit::verify_exception_state(SafePointNode* ex_map) {
158 assert(ex_map->next_exception() == nullptr, "not already part of a chain");
159 assert(has_saved_ex_oop(ex_map), "every exception state has an ex_oop");
160 }
161 #endif
162
163 //---------------------------stop_and_kill_map---------------------------------
164 // Set _map to null, signalling a stop to further bytecode execution.
165 // First smash the current map's control to a constant, to mark it dead.
166 void GraphKit::stop_and_kill_map() {
167 SafePointNode* dead_map = stop();
168 if (dead_map != nullptr) {
169 dead_map->disconnect_inputs(C); // Mark the map as killed.
170 assert(dead_map->is_killed(), "must be so marked");
171 }
172 }
173
174
175 //--------------------------------stopped--------------------------------------
176 // Tell if _map is null, or control is top.
177 bool GraphKit::stopped() {
178 if (map() == nullptr) return true;
179 else if (control() == top()) return true;
180 else return false;
181 }
182
183
184 //-----------------------------has_exception_handler----------------------------------
185 // Tell if this method or any caller method has exception handlers.
186 bool GraphKit::has_exception_handler() {
187 for (JVMState* jvmsp = jvms(); jvmsp != nullptr; jvmsp = jvmsp->caller()) {
188 if (jvmsp->has_method() && jvmsp->method()->has_exception_handlers()) {
189 return true;
190 }
191 }
192 return false;
193 }
194
195 //------------------------------save_ex_oop------------------------------------
196 // Save an exception without blowing stack contents or other JVM state.
197 void GraphKit::set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop) {
198 assert(!has_saved_ex_oop(ex_map), "clear ex-oop before setting again");
199 ex_map->add_req(ex_oop);
200 DEBUG_ONLY(verify_exception_state(ex_map));
201 }
202
203 inline static Node* common_saved_ex_oop(SafePointNode* ex_map, bool clear_it) {
204 assert(GraphKit::has_saved_ex_oop(ex_map), "ex_oop must be there");
205 Node* ex_oop = ex_map->in(ex_map->req()-1);
206 if (clear_it) ex_map->del_req(ex_map->req()-1);
207 return ex_oop;
208 }
209
210 //-----------------------------saved_ex_oop------------------------------------
211 // Recover a saved exception from its map.
212 Node* GraphKit::saved_ex_oop(SafePointNode* ex_map) {
213 return common_saved_ex_oop(ex_map, false);
214 }
215
216 //--------------------------clear_saved_ex_oop---------------------------------
217 // Erase a previously saved exception from its map.
218 Node* GraphKit::clear_saved_ex_oop(SafePointNode* ex_map) {
219 return common_saved_ex_oop(ex_map, true);
220 }
221
222 #ifdef ASSERT
223 //---------------------------has_saved_ex_oop----------------------------------
224 // Erase a previously saved exception from its map.
225 bool GraphKit::has_saved_ex_oop(SafePointNode* ex_map) {
226 return ex_map->req() == ex_map->jvms()->endoff()+1;
227 }
228 #endif
229
230 //-------------------------make_exception_state--------------------------------
231 // Turn the current JVM state into an exception state, appending the ex_oop.
232 SafePointNode* GraphKit::make_exception_state(Node* ex_oop) {
233 sync_jvms();
234 SafePointNode* ex_map = stop(); // do not manipulate this map any more
235 set_saved_ex_oop(ex_map, ex_oop);
236 return ex_map;
237 }
238
239
240 //--------------------------add_exception_state--------------------------------
241 // Add an exception to my list of exceptions.
242 void GraphKit::add_exception_state(SafePointNode* ex_map) {
243 if (ex_map == nullptr || ex_map->control() == top()) {
244 return;
245 }
246 #ifdef ASSERT
247 verify_exception_state(ex_map);
248 if (has_exceptions()) {
249 assert(ex_map->jvms()->same_calls_as(_exceptions->jvms()), "all collected exceptions must come from the same place");
250 }
251 #endif
252
253 // If there is already an exception of exactly this type, merge with it.
254 // In particular, null-checks and other low-level exceptions common up here.
255 Node* ex_oop = saved_ex_oop(ex_map);
256 const Type* ex_type = _gvn.type(ex_oop);
257 if (ex_oop == top()) {
258 // No action needed.
259 return;
260 }
261 assert(ex_type->isa_instptr(), "exception must be an instance");
262 for (SafePointNode* e2 = _exceptions; e2 != nullptr; e2 = e2->next_exception()) {
263 const Type* ex_type2 = _gvn.type(saved_ex_oop(e2));
264 // We check sp also because call bytecodes can generate exceptions
265 // both before and after arguments are popped!
266 if (ex_type2 == ex_type
267 && e2->_jvms->sp() == ex_map->_jvms->sp()) {
268 combine_exception_states(ex_map, e2);
269 return;
270 }
271 }
272
273 // No pre-existing exception of the same type. Chain it on the list.
274 push_exception_state(ex_map);
275 }
276
277 //-----------------------add_exception_states_from-----------------------------
278 void GraphKit::add_exception_states_from(JVMState* jvms) {
279 SafePointNode* ex_map = jvms->map()->next_exception();
280 if (ex_map != nullptr) {
281 jvms->map()->set_next_exception(nullptr);
282 for (SafePointNode* next_map; ex_map != nullptr; ex_map = next_map) {
283 next_map = ex_map->next_exception();
284 ex_map->set_next_exception(nullptr);
285 add_exception_state(ex_map);
286 }
287 }
288 }
289
290 //-----------------------transfer_exceptions_into_jvms-------------------------
291 JVMState* GraphKit::transfer_exceptions_into_jvms() {
292 if (map() == nullptr) {
293 // We need a JVMS to carry the exceptions, but the map has gone away.
294 // Create a scratch JVMS, cloned from any of the exception states...
295 if (has_exceptions()) {
296 _map = _exceptions;
297 _map = clone_map();
298 _map->set_next_exception(nullptr);
299 clear_saved_ex_oop(_map);
300 DEBUG_ONLY(verify_map());
301 } else {
302 // ...or created from scratch
303 JVMState* jvms = new (C) JVMState(_method, nullptr);
304 jvms->set_bci(_bci);
305 jvms->set_sp(_sp);
306 jvms->set_map(new SafePointNode(TypeFunc::Parms, jvms));
307 set_jvms(jvms);
308 for (uint i = 0; i < map()->req(); i++) map()->init_req(i, top());
309 set_all_memory(top());
310 while (map()->req() < jvms->endoff()) map()->add_req(top());
311 }
312 // (This is a kludge, in case you didn't notice.)
313 set_control(top());
314 }
315 JVMState* jvms = sync_jvms();
316 assert(!jvms->map()->has_exceptions(), "no exceptions on this map yet");
317 jvms->map()->set_next_exception(_exceptions);
318 _exceptions = nullptr; // done with this set of exceptions
319 return jvms;
320 }
321
322 static inline void add_n_reqs(Node* dstphi, Node* srcphi) {
323 assert(is_hidden_merge(dstphi), "must be a special merge node");
324 assert(is_hidden_merge(srcphi), "must be a special merge node");
325 uint limit = srcphi->req();
326 for (uint i = PhiNode::Input; i < limit; i++) {
327 dstphi->add_req(srcphi->in(i));
328 }
329 }
330 static inline void add_one_req(Node* dstphi, Node* src) {
331 assert(is_hidden_merge(dstphi), "must be a special merge node");
332 assert(!is_hidden_merge(src), "must not be a special merge node");
333 dstphi->add_req(src);
334 }
335
336 //-----------------------combine_exception_states------------------------------
337 // This helper function combines exception states by building phis on a
338 // specially marked state-merging region. These regions and phis are
339 // untransformed, and can build up gradually. The region is marked by
340 // having a control input of its exception map, rather than null. Such
341 // regions do not appear except in this function, and in use_exception_state.
342 void GraphKit::combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map) {
343 if (failing_internal()) {
344 return; // dying anyway...
345 }
346 JVMState* ex_jvms = ex_map->_jvms;
347 assert(ex_jvms->same_calls_as(phi_map->_jvms), "consistent call chains");
348 assert(ex_jvms->stkoff() == phi_map->_jvms->stkoff(), "matching locals");
349 assert(ex_jvms->sp() == phi_map->_jvms->sp(), "matching stack sizes");
350 assert(ex_jvms->monoff() == phi_map->_jvms->monoff(), "matching JVMS");
351 assert(ex_jvms->scloff() == phi_map->_jvms->scloff(), "matching scalar replaced objects");
352 assert(ex_map->req() == phi_map->req(), "matching maps");
353 uint tos = ex_jvms->stkoff() + ex_jvms->sp();
354 Node* hidden_merge_mark = root();
355 Node* region = phi_map->control();
356 MergeMemNode* phi_mem = phi_map->merged_memory();
357 MergeMemNode* ex_mem = ex_map->merged_memory();
358 if (region->in(0) != hidden_merge_mark) {
359 // The control input is not (yet) a specially-marked region in phi_map.
360 // Make it so, and build some phis.
361 region = new RegionNode(2);
362 _gvn.set_type(region, Type::CONTROL);
363 region->set_req(0, hidden_merge_mark); // marks an internal ex-state
364 region->init_req(1, phi_map->control());
365 phi_map->set_control(region);
366 Node* io_phi = PhiNode::make(region, phi_map->i_o(), Type::ABIO);
367 record_for_igvn(io_phi);
368 _gvn.set_type(io_phi, Type::ABIO);
369 phi_map->set_i_o(io_phi);
370 for (MergeMemStream mms(phi_mem); mms.next_non_empty(); ) {
371 Node* m = mms.memory();
372 Node* m_phi = PhiNode::make(region, m, Type::MEMORY, mms.adr_type(C));
373 record_for_igvn(m_phi);
374 _gvn.set_type(m_phi, Type::MEMORY);
375 mms.set_memory(m_phi);
376 }
377 }
378
379 // Either or both of phi_map and ex_map might already be converted into phis.
380 Node* ex_control = ex_map->control();
381 // if there is special marking on ex_map also, we add multiple edges from src
382 bool add_multiple = (ex_control->in(0) == hidden_merge_mark);
383 // how wide was the destination phi_map, originally?
384 uint orig_width = region->req();
385
386 if (add_multiple) {
387 add_n_reqs(region, ex_control);
388 add_n_reqs(phi_map->i_o(), ex_map->i_o());
389 } else {
390 // ex_map has no merges, so we just add single edges everywhere
391 add_one_req(region, ex_control);
392 add_one_req(phi_map->i_o(), ex_map->i_o());
393 }
394 for (MergeMemStream mms(phi_mem, ex_mem); mms.next_non_empty2(); ) {
395 if (mms.is_empty()) {
396 // get a copy of the base memory, and patch some inputs into it
397 const TypePtr* adr_type = mms.adr_type(C);
398 Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
399 assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
400 mms.set_memory(phi);
401 // Prepare to append interesting stuff onto the newly sliced phi:
402 while (phi->req() > orig_width) phi->del_req(phi->req()-1);
403 }
404 // Append stuff from ex_map:
405 if (add_multiple) {
406 add_n_reqs(mms.memory(), mms.memory2());
407 } else {
408 add_one_req(mms.memory(), mms.memory2());
409 }
410 }
411 uint limit = ex_map->req();
412 for (uint i = TypeFunc::Parms; i < limit; i++) {
413 // Skip everything in the JVMS after tos. (The ex_oop follows.)
414 if (i == tos) i = ex_jvms->monoff();
415 Node* src = ex_map->in(i);
416 Node* dst = phi_map->in(i);
417 if (src != dst) {
418 PhiNode* phi;
419 if (dst->in(0) != region) {
420 dst = phi = PhiNode::make(region, dst, _gvn.type(dst));
421 record_for_igvn(phi);
422 _gvn.set_type(phi, phi->type());
423 phi_map->set_req(i, dst);
424 // Prepare to append interesting stuff onto the new phi:
425 while (dst->req() > orig_width) dst->del_req(dst->req()-1);
426 } else {
427 assert(dst->is_Phi(), "nobody else uses a hidden region");
428 phi = dst->as_Phi();
429 }
430 if (add_multiple && src->in(0) == ex_control) {
431 // Both are phis.
432 add_n_reqs(dst, src);
433 } else {
434 while (dst->req() < region->req()) add_one_req(dst, src);
435 }
436 const Type* srctype = _gvn.type(src);
437 if (phi->type() != srctype) {
438 const Type* dsttype = phi->type()->meet_speculative(srctype);
439 if (phi->type() != dsttype) {
440 phi->set_type(dsttype);
441 _gvn.set_type(phi, dsttype);
442 }
443 }
444 }
445 }
446 phi_map->merge_replaced_nodes_with(ex_map);
447 }
448
449 //--------------------------use_exception_state--------------------------------
450 Node* GraphKit::use_exception_state(SafePointNode* phi_map) {
451 if (failing_internal()) { stop(); return top(); }
452 Node* region = phi_map->control();
453 Node* hidden_merge_mark = root();
454 assert(phi_map->jvms()->map() == phi_map, "sanity: 1-1 relation");
455 Node* ex_oop = clear_saved_ex_oop(phi_map);
456 if (region->in(0) == hidden_merge_mark) {
457 // Special marking for internal ex-states. Process the phis now.
458 region->set_req(0, region); // now it's an ordinary region
459 set_jvms(phi_map->jvms()); // ...so now we can use it as a map
460 // Note: Setting the jvms also sets the bci and sp.
461 set_control(_gvn.transform(region));
462 uint tos = jvms()->stkoff() + sp();
463 for (uint i = 1; i < tos; i++) {
464 Node* x = phi_map->in(i);
465 if (x->in(0) == region) {
466 assert(x->is_Phi(), "expected a special phi");
467 phi_map->set_req(i, _gvn.transform(x));
468 }
469 }
470 for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
471 Node* x = mms.memory();
472 if (x->in(0) == region) {
473 assert(x->is_Phi(), "nobody else uses a hidden region");
474 mms.set_memory(_gvn.transform(x));
475 }
476 }
477 if (ex_oop->in(0) == region) {
478 assert(ex_oop->is_Phi(), "expected a special phi");
479 ex_oop = _gvn.transform(ex_oop);
480 }
481 } else {
482 set_jvms(phi_map->jvms());
483 }
484
485 assert(!is_hidden_merge(phi_map->control()), "hidden ex. states cleared");
486 assert(!is_hidden_merge(phi_map->i_o()), "hidden ex. states cleared");
487 return ex_oop;
488 }
489
490 //---------------------------------java_bc-------------------------------------
491 Bytecodes::Code GraphKit::java_bc() const {
492 ciMethod* method = this->method();
493 int bci = this->bci();
494 if (method != nullptr && bci != InvocationEntryBci)
495 return method->java_code_at_bci(bci);
496 else
497 return Bytecodes::_illegal;
498 }
499
500 void GraphKit::uncommon_trap_if_should_post_on_exceptions(Deoptimization::DeoptReason reason,
501 bool must_throw) {
502 // if the exception capability is set, then we will generate code
503 // to check the JavaThread.should_post_on_exceptions flag to see
504 // if we actually need to report exception events (for this
505 // thread). If we don't need to report exception events, we will
506 // take the normal fast path provided by add_exception_events. If
507 // exception event reporting is enabled for this thread, we will
508 // take the uncommon_trap in the BuildCutout below.
509
510 // first must access the should_post_on_exceptions_flag in this thread's JavaThread
511 Node* jthread = _gvn.transform(new ThreadLocalNode());
512 Node* adr = off_heap_plus_addr(jthread, in_bytes(JavaThread::should_post_on_exceptions_flag_offset()));
513 Node* should_post_flag = make_load(control(), adr, TypeInt::INT, T_INT, MemNode::unordered);
514
515 // Test the should_post_on_exceptions_flag vs. 0
516 Node* chk = _gvn.transform( new CmpINode(should_post_flag, intcon(0)) );
517 Node* tst = _gvn.transform( new BoolNode(chk, BoolTest::eq) );
518
519 // Branch to slow_path if should_post_on_exceptions_flag was true
520 { BuildCutout unless(this, tst, PROB_MAX);
521 // Do not try anything fancy if we're notifying the VM on every throw.
522 // Cf. case Bytecodes::_athrow in parse2.cpp.
523 uncommon_trap(reason, Deoptimization::Action_none,
524 (ciKlass*)nullptr, (char*)nullptr, must_throw);
525 }
526
527 }
528
529 //------------------------------builtin_throw----------------------------------
530 void GraphKit::builtin_throw(Deoptimization::DeoptReason reason) {
531 builtin_throw(reason, builtin_throw_exception(reason), /*allow_too_many_traps*/ true);
532 }
533
534 void GraphKit::builtin_throw(Deoptimization::DeoptReason reason,
535 ciInstance* ex_obj,
536 bool allow_too_many_traps) {
537 // If this throw happens frequently, an uncommon trap might cause
538 // a performance pothole. If there is a local exception handler,
539 // and if this particular bytecode appears to be deoptimizing often,
540 // let us handle the throw inline, with a preconstructed instance.
541 // Note: If the deopt count has blown up, the uncommon trap
542 // runtime is going to flush this nmethod, not matter what.
543 if (is_builtin_throw_hot(reason)) {
544 if (method()->can_omit_stack_trace() && ex_obj != nullptr) {
545 // If the throw is local, we use a pre-existing instance and
546 // punt on the backtrace. This would lead to a missing backtrace
547 // (a repeat of 4292742) if the backtrace object is ever asked
548 // for its backtrace.
549 // Fixing this remaining case of 4292742 requires some flavor of
550 // escape analysis. Leave that for the future.
551 if (env()->jvmti_can_post_on_exceptions()) {
552 // check if we must post exception events, take uncommon trap if so
553 uncommon_trap_if_should_post_on_exceptions(reason, true /*must_throw*/);
554 // here if should_post_on_exceptions is false
555 // continue on with the normal codegen
556 }
557
558 // Cheat with a preallocated exception object.
559 if (C->log() != nullptr)
560 C->log()->elem("hot_throw preallocated='1' reason='%s'",
561 Deoptimization::trap_reason_name(reason));
562 const TypeInstPtr* ex_con = TypeInstPtr::make(ex_obj);
563 Node* ex_node = _gvn.transform(ConNode::make(ex_con));
564
565 // Clear the detail message of the preallocated exception object.
566 // Weblogic sometimes mutates the detail message of exceptions
567 // using reflection.
568 int offset = java_lang_Throwable::get_detailMessage_offset();
569 const TypePtr* adr_typ = ex_con->add_offset(offset);
570
571 Node *adr = basic_plus_adr(ex_node, ex_node, offset);
572 const TypeOopPtr* val_type = TypeOopPtr::make_from_klass(env()->String_klass());
573 Node *store = access_store_at(ex_node, adr, adr_typ, null(), val_type, T_OBJECT, IN_HEAP);
574
575 if (!method()->has_exception_handlers()) {
576 // We don't need to preserve the stack if there's no handler as the entire frame is going to be popped anyway.
577 // This prevents issues with exception handling and late inlining.
578 set_sp(0);
579 clean_stack(0);
580 }
581
582 add_exception_state(make_exception_state(ex_node));
583 return;
584 } else if (builtin_throw_too_many_traps(reason, ex_obj)) {
585 // We cannot afford to take too many traps here. Suffer in the interpreter instead.
586 assert(allow_too_many_traps, "not allowed");
587 if (C->log() != nullptr) {
588 C->log()->elem("hot_throw preallocated='0' reason='%s' mcount='%d'",
589 Deoptimization::trap_reason_name(reason),
590 C->trap_count(reason));
591 }
592 uncommon_trap(reason, Deoptimization::Action_none,
593 (ciKlass*) nullptr, (char*) nullptr,
594 true /*must_throw*/);
595 return;
596 }
597 }
598
599 // %%% Maybe add entry to OptoRuntime which directly throws the exc.?
600 // It won't be much cheaper than bailing to the interp., since we'll
601 // have to pass up all the debug-info, and the runtime will have to
602 // create the stack trace.
603
604 // Usual case: Bail to interpreter.
605 // Reserve the right to recompile if we haven't seen anything yet.
606
607 // "must_throw" prunes the JVM state to include only the stack, if there
608 // are no local exception handlers. This should cut down on register
609 // allocation time and code size, by drastically reducing the number
610 // of in-edges on the call to the uncommon trap.
611 uncommon_trap(reason, Deoptimization::Action_maybe_recompile,
612 (ciKlass*) nullptr, (char*) nullptr,
613 true /*must_throw*/);
614 }
615
616 bool GraphKit::is_builtin_throw_hot(Deoptimization::DeoptReason reason) {
617 // If this particular condition has not yet happened at this
618 // bytecode, then use the uncommon trap mechanism, and allow for
619 // a future recompilation if several traps occur here.
620 // If the throw is hot, try to use a more complicated inline mechanism
621 // which keeps execution inside the compiled code.
622 if (ProfileTraps) {
623 if (too_many_traps(reason)) {
624 return true;
625 }
626 // (If there is no MDO at all, assume it is early in
627 // execution, and that any deopts are part of the
628 // startup transient, and don't need to be remembered.)
629
630 // Also, if there is a local exception handler, treat all throws
631 // as hot if there has been at least one in this method.
632 if (C->trap_count(reason) != 0 &&
633 method()->method_data()->trap_count(reason) != 0 &&
634 has_exception_handler()) {
635 return true;
636 }
637 }
638 return false;
639 }
640
641 bool GraphKit::builtin_throw_too_many_traps(Deoptimization::DeoptReason reason,
642 ciInstance* ex_obj) {
643 if (is_builtin_throw_hot(reason)) {
644 if (method()->can_omit_stack_trace() && ex_obj != nullptr) {
645 return false; // no traps; throws preallocated exception instead
646 }
647 ciMethod* m = Deoptimization::reason_is_speculate(reason) ? C->method() : nullptr;
648 if (method()->method_data()->trap_recompiled_at(bci(), m) ||
649 C->too_many_traps(reason)) {
650 return true;
651 }
652 }
653 return false;
654 }
655
656 ciInstance* GraphKit::builtin_throw_exception(Deoptimization::DeoptReason reason) const {
657 // Preallocated exception objects to use when we don't need the backtrace.
658 switch (reason) {
659 case Deoptimization::Reason_null_check:
660 return env()->NullPointerException_instance();
661 case Deoptimization::Reason_div0_check:
662 return env()->ArithmeticException_instance();
663 case Deoptimization::Reason_range_check:
664 return env()->ArrayIndexOutOfBoundsException_instance();
665 case Deoptimization::Reason_class_check:
666 return env()->ClassCastException_instance();
667 case Deoptimization::Reason_array_check:
668 return env()->ArrayStoreException_instance();
669 default:
670 return nullptr;
671 }
672 }
673
674 GraphKit::SavedState::SavedState(GraphKit* kit) :
675 _kit(kit),
676 _sp(kit->sp()),
677 _jvms(kit->jvms()),
678 _map(kit->clone_map()),
679 _discarded(false)
680 {
681 for (DUIterator_Fast imax, i = kit->control()->fast_outs(imax); i < imax; i++) {
682 Node* out = kit->control()->fast_out(i);
683 if (out->is_CFG()) {
684 _ctrl_succ.push(out);
685 }
686 }
687 }
688
689 GraphKit::SavedState::~SavedState() {
690 if (_discarded) {
691 _kit->destruct_map_clone(_map);
692 return;
693 }
694 _kit->jvms()->set_map(_map);
695 _kit->jvms()->set_sp(_sp);
696 _map->set_jvms(_kit->jvms());
697 _kit->set_map(_map);
698 _kit->set_sp(_sp);
699 for (DUIterator_Fast imax, i = _kit->control()->fast_outs(imax); i < imax; i++) {
700 Node* out = _kit->control()->fast_out(i);
701 if (out->is_CFG() && out->in(0) == _kit->control() && out != _kit->map() && !_ctrl_succ.member(out)) {
702 _kit->_gvn.hash_delete(out);
703 out->set_req(0, _kit->C->top());
704 _kit->C->record_for_igvn(out);
705 --i; --imax;
706 _kit->_gvn.hash_find_insert(out);
707 }
708 }
709 }
710
711 void GraphKit::SavedState::discard() {
712 _discarded = true;
713 }
714
715
716 //----------------------------PreserveJVMState---------------------------------
717 PreserveJVMState::PreserveJVMState(GraphKit* kit, bool clone_map) {
718 DEBUG_ONLY(kit->verify_map());
719 _kit = kit;
720 _map = kit->map(); // preserve the map
721 _sp = kit->sp();
722 kit->set_map(clone_map ? kit->clone_map() : nullptr);
723 #ifdef ASSERT
724 _bci = kit->bci();
725 Parse* parser = kit->is_Parse();
726 int block = (parser == nullptr || parser->block() == nullptr) ? -1 : parser->block()->rpo();
727 _block = block;
728 #endif
729 }
730 PreserveJVMState::~PreserveJVMState() {
731 GraphKit* kit = _kit;
732 #ifdef ASSERT
733 assert(kit->bci() == _bci, "bci must not shift");
734 Parse* parser = kit->is_Parse();
735 int block = (parser == nullptr || parser->block() == nullptr) ? -1 : parser->block()->rpo();
736 assert(block == _block, "block must not shift");
737 #endif
738 kit->set_map(_map);
739 kit->set_sp(_sp);
740 }
741
742
743 //-----------------------------BuildCutout-------------------------------------
744 BuildCutout::BuildCutout(GraphKit* kit, Node* p, float prob, float cnt)
745 : PreserveJVMState(kit)
746 {
747 assert(p->is_Con() || p->is_Bool(), "test must be a bool");
748 SafePointNode* outer_map = _map; // preserved map is caller's
749 SafePointNode* inner_map = kit->map();
750 IfNode* iff = kit->create_and_map_if(outer_map->control(), p, prob, cnt);
751 outer_map->set_control(kit->gvn().transform( new IfTrueNode(iff) ));
752 inner_map->set_control(kit->gvn().transform( new IfFalseNode(iff) ));
753 }
754 BuildCutout::~BuildCutout() {
755 GraphKit* kit = _kit;
756 assert(kit->stopped(), "cutout code must stop, throw, return, etc.");
757 }
758
759 //---------------------------PreserveReexecuteState----------------------------
760 PreserveReexecuteState::PreserveReexecuteState(GraphKit* kit) {
761 assert(!kit->stopped(), "must call stopped() before");
762 _kit = kit;
763 _sp = kit->sp();
764 _reexecute = kit->jvms()->_reexecute;
765 }
766 PreserveReexecuteState::~PreserveReexecuteState() {
767 if (_kit->stopped()) return;
768 _kit->jvms()->_reexecute = _reexecute;
769 _kit->set_sp(_sp);
770 }
771
772 //------------------------------clone_map--------------------------------------
773 // Implementation of PreserveJVMState
774 //
775 // Only clone_map(...) here. If this function is only used in the
776 // PreserveJVMState class we may want to get rid of this extra
777 // function eventually and do it all there.
778
779 SafePointNode* GraphKit::clone_map() {
780 if (map() == nullptr) return nullptr;
781
782 // Clone the memory edge first
783 Node* mem = MergeMemNode::make(map()->memory());
784 gvn().set_type_bottom(mem);
785
786 SafePointNode *clonemap = (SafePointNode*)map()->clone();
787 JVMState* jvms = this->jvms();
788 JVMState* clonejvms = jvms->clone_shallow(C);
789 clonemap->set_memory(mem);
790 clonemap->set_jvms(clonejvms);
791 clonejvms->set_map(clonemap);
792 record_for_igvn(clonemap);
793 gvn().set_type_bottom(clonemap);
794 return clonemap;
795 }
796
797 //-----------------------------destruct_map_clone------------------------------
798 //
799 // Order of destruct is important to increase the likelyhood that memory can be re-used. We need
800 // to destruct/free/delete in the exact opposite order as clone_map().
801 void GraphKit::destruct_map_clone(SafePointNode* sfp) {
802 if (sfp == nullptr) return;
803
804 Node* mem = sfp->memory();
805 JVMState* jvms = sfp->jvms();
806
807 if (jvms != nullptr) {
808 delete jvms;
809 }
810
811 remove_for_igvn(sfp);
812 gvn().clear_type(sfp);
813 sfp->destruct(&_gvn);
814
815 if (mem != nullptr) {
816 gvn().clear_type(mem);
817 mem->destruct(&_gvn);
818 }
819 }
820
821 //-----------------------------set_map_clone-----------------------------------
822 void GraphKit::set_map_clone(SafePointNode* m) {
823 _map = m;
824 _map = clone_map();
825 _map->set_next_exception(nullptr);
826 DEBUG_ONLY(verify_map());
827 }
828
829
830 //----------------------------kill_dead_locals---------------------------------
831 // Detect any locals which are known to be dead, and force them to top.
832 void GraphKit::kill_dead_locals() {
833 // Consult the liveness information for the locals. If any
834 // of them are unused, then they can be replaced by top(). This
835 // should help register allocation time and cut down on the size
836 // of the deoptimization information.
837
838 // This call is made from many of the bytecode handling
839 // subroutines called from the Big Switch in do_one_bytecode.
840 // Every bytecode which might include a slow path is responsible
841 // for killing its dead locals. The more consistent we
842 // are about killing deads, the fewer useless phis will be
843 // constructed for them at various merge points.
844
845 // bci can be -1 (InvocationEntryBci). We return the entry
846 // liveness for the method.
847
848 if (method() == nullptr || method()->code_size() == 0) {
849 // We are building a graph for a call to a native method.
850 // All locals are live.
851 return;
852 }
853
854 ResourceMark rm;
855
856 // Consult the liveness information for the locals. If any
857 // of them are unused, then they can be replaced by top(). This
858 // should help register allocation time and cut down on the size
859 // of the deoptimization information.
860 MethodLivenessResult live_locals = method()->liveness_at_bci(bci());
861
862 int len = (int)live_locals.size();
863 assert(len <= jvms()->loc_size(), "too many live locals");
864 for (int local = 0; local < len; local++) {
865 if (!live_locals.at(local)) {
866 set_local(local, top());
867 }
868 }
869 }
870
871 #ifdef ASSERT
872 //-------------------------dead_locals_are_killed------------------------------
873 // Return true if all dead locals are set to top in the map.
874 // Used to assert "clean" debug info at various points.
875 bool GraphKit::dead_locals_are_killed() {
876 if (method() == nullptr || method()->code_size() == 0) {
877 // No locals need to be dead, so all is as it should be.
878 return true;
879 }
880
881 // Make sure somebody called kill_dead_locals upstream.
882 ResourceMark rm;
883 for (JVMState* jvms = this->jvms(); jvms != nullptr; jvms = jvms->caller()) {
884 if (jvms->loc_size() == 0) continue; // no locals to consult
885 SafePointNode* map = jvms->map();
886 ciMethod* method = jvms->method();
887 int bci = jvms->bci();
888 if (jvms == this->jvms()) {
889 bci = this->bci(); // it might not yet be synched
890 }
891 MethodLivenessResult live_locals = method->liveness_at_bci(bci);
892 int len = (int)live_locals.size();
893 if (!live_locals.is_valid() || len == 0)
894 // This method is trivial, or is poisoned by a breakpoint.
895 return true;
896 assert(len == jvms->loc_size(), "live map consistent with locals map");
897 for (int local = 0; local < len; local++) {
898 if (!live_locals.at(local) && map->local(jvms, local) != top()) {
899 if (PrintMiscellaneous && (Verbose || WizardMode)) {
900 tty->print_cr("Zombie local %d: ", local);
901 jvms->dump();
902 }
903 return false;
904 }
905 }
906 }
907 return true;
908 }
909
910 #endif //ASSERT
911
912 // Helper function for enforcing certain bytecodes to reexecute if deoptimization happens.
913 static bool should_reexecute_implied_by_bytecode(JVMState *jvms, bool is_anewarray) {
914 ciMethod* cur_method = jvms->method();
915 int cur_bci = jvms->bci();
916 if (cur_method != nullptr && cur_bci != InvocationEntryBci) {
917 Bytecodes::Code code = cur_method->java_code_at_bci(cur_bci);
918 return Interpreter::bytecode_should_reexecute(code) ||
919 (is_anewarray && code == Bytecodes::_multianewarray);
920 // Reexecute _multianewarray bytecode which was replaced with
921 // sequence of [a]newarray. See Parse::do_multianewarray().
922 //
923 // Note: interpreter should not have it set since this optimization
924 // is limited by dimensions and guarded by flag so in some cases
925 // multianewarray() runtime calls will be generated and
926 // the bytecode should not be reexecutes (stack will not be reset).
927 } else {
928 return false;
929 }
930 }
931
932 // Helper function for adding JVMState and debug information to node
933 void GraphKit::add_safepoint_edges(SafePointNode* call, bool must_throw) {
934 // Add the safepoint edges to the call (or other safepoint).
935
936 // Make sure dead locals are set to top. This
937 // should help register allocation time and cut down on the size
938 // of the deoptimization information.
939 assert(dead_locals_are_killed(), "garbage in debug info before safepoint");
940
941 // Walk the inline list to fill in the correct set of JVMState's
942 // Also fill in the associated edges for each JVMState.
943
944 // If the bytecode needs to be reexecuted we need to put
945 // the arguments back on the stack.
946 const bool should_reexecute = jvms()->should_reexecute();
947 JVMState* youngest_jvms = should_reexecute ? sync_jvms_for_reexecute() : sync_jvms();
948
949 // NOTE: set_bci (called from sync_jvms) might reset the reexecute bit to
950 // undefined if the bci is different. This is normal for Parse but it
951 // should not happen for LibraryCallKit because only one bci is processed.
952 assert(!is_LibraryCallKit() || (jvms()->should_reexecute() == should_reexecute),
953 "in LibraryCallKit the reexecute bit should not change");
954
955 // If we are guaranteed to throw, we can prune everything but the
956 // input to the current bytecode.
957 bool can_prune_locals = false;
958 uint stack_slots_not_pruned = 0;
959 int inputs = 0, depth = 0;
960 if (must_throw) {
961 assert(method() == youngest_jvms->method(), "sanity");
962 if (compute_stack_effects(inputs, depth)) {
963 can_prune_locals = true;
964 stack_slots_not_pruned = inputs;
965 }
966 }
967
968 if (env()->should_retain_local_variables()) {
969 // At any safepoint, this method can get breakpointed, which would
970 // then require an immediate deoptimization.
971 can_prune_locals = false; // do not prune locals
972 stack_slots_not_pruned = 0;
973 }
974
975 // do not scribble on the input jvms
976 JVMState* out_jvms = youngest_jvms->clone_deep(C);
977 call->set_jvms(out_jvms); // Start jvms list for call node
978
979 // For a known set of bytecodes, the interpreter should reexecute them if
980 // deoptimization happens. We set the reexecute state for them here
981 if (out_jvms->is_reexecute_undefined() && //don't change if already specified
982 should_reexecute_implied_by_bytecode(out_jvms, call->is_AllocateArray())) {
983 #ifdef ASSERT
984 int inputs = 0, not_used; // initialized by GraphKit::compute_stack_effects()
985 assert(method() == youngest_jvms->method(), "sanity");
986 assert(compute_stack_effects(inputs, not_used), "unknown bytecode: %s", Bytecodes::name(java_bc()));
987 assert(out_jvms->sp() >= (uint)inputs, "not enough operands for reexecution");
988 #endif // ASSERT
989 out_jvms->set_should_reexecute(true); //NOTE: youngest_jvms not changed
990 }
991
992 // Presize the call:
993 DEBUG_ONLY(uint non_debug_edges = call->req());
994 call->add_req_batch(top(), youngest_jvms->debug_depth());
995 assert(call->req() == non_debug_edges + youngest_jvms->debug_depth(), "");
996
997 // Set up edges so that the call looks like this:
998 // Call [state:] ctl io mem fptr retadr
999 // [parms:] parm0 ... parmN
1000 // [root:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
1001 // [...mid:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN [...]
1002 // [young:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
1003 // Note that caller debug info precedes callee debug info.
1004
1005 // Fill pointer walks backwards from "young:" to "root:" in the diagram above:
1006 uint debug_ptr = call->req();
1007
1008 // Loop over the map input edges associated with jvms, add them
1009 // to the call node, & reset all offsets to match call node array.
1010 for (JVMState* in_jvms = youngest_jvms; in_jvms != nullptr; ) {
1011 uint debug_end = debug_ptr;
1012 uint debug_start = debug_ptr - in_jvms->debug_size();
1013 debug_ptr = debug_start; // back up the ptr
1014
1015 uint p = debug_start; // walks forward in [debug_start, debug_end)
1016 uint j, k, l;
1017 SafePointNode* in_map = in_jvms->map();
1018 out_jvms->set_map(call);
1019
1020 if (can_prune_locals) {
1021 assert(in_jvms->method() == out_jvms->method(), "sanity");
1022 // If the current throw can reach an exception handler in this JVMS,
1023 // then we must keep everything live that can reach that handler.
1024 // As a quick and dirty approximation, we look for any handlers at all.
1025 if (in_jvms->method()->has_exception_handlers()) {
1026 can_prune_locals = false;
1027 }
1028 }
1029
1030 // Add the Locals
1031 k = in_jvms->locoff();
1032 l = in_jvms->loc_size();
1033 out_jvms->set_locoff(p);
1034 if (!can_prune_locals) {
1035 for (j = 0; j < l; j++)
1036 call->set_req(p++, in_map->in(k+j));
1037 } else {
1038 p += l; // already set to top above by add_req_batch
1039 }
1040
1041 // Add the Expression Stack
1042 k = in_jvms->stkoff();
1043 l = in_jvms->sp();
1044 out_jvms->set_stkoff(p);
1045 if (!can_prune_locals) {
1046 for (j = 0; j < l; j++)
1047 call->set_req(p++, in_map->in(k+j));
1048 } else if (can_prune_locals && stack_slots_not_pruned != 0) {
1049 // Divide stack into {S0,...,S1}, where S0 is set to top.
1050 uint s1 = stack_slots_not_pruned;
1051 stack_slots_not_pruned = 0; // for next iteration
1052 if (s1 > l) s1 = l;
1053 uint s0 = l - s1;
1054 p += s0; // skip the tops preinstalled by add_req_batch
1055 for (j = s0; j < l; j++)
1056 call->set_req(p++, in_map->in(k+j));
1057 } else {
1058 p += l; // already set to top above by add_req_batch
1059 }
1060
1061 // Add the Monitors
1062 k = in_jvms->monoff();
1063 l = in_jvms->mon_size();
1064 out_jvms->set_monoff(p);
1065 for (j = 0; j < l; j++)
1066 call->set_req(p++, in_map->in(k+j));
1067
1068 // Copy any scalar object fields.
1069 k = in_jvms->scloff();
1070 l = in_jvms->scl_size();
1071 out_jvms->set_scloff(p);
1072 for (j = 0; j < l; j++)
1073 call->set_req(p++, in_map->in(k+j));
1074
1075 // Finish the new jvms.
1076 out_jvms->set_endoff(p);
1077
1078 assert(out_jvms->endoff() == debug_end, "fill ptr must match");
1079 assert(out_jvms->depth() == in_jvms->depth(), "depth must match");
1080 assert(out_jvms->loc_size() == in_jvms->loc_size(), "size must match");
1081 assert(out_jvms->mon_size() == in_jvms->mon_size(), "size must match");
1082 assert(out_jvms->scl_size() == in_jvms->scl_size(), "size must match");
1083 assert(out_jvms->debug_size() == in_jvms->debug_size(), "size must match");
1084
1085 // Update the two tail pointers in parallel.
1086 out_jvms = out_jvms->caller();
1087 in_jvms = in_jvms->caller();
1088 }
1089
1090 assert(debug_ptr == non_debug_edges, "debug info must fit exactly");
1091
1092 // Test the correctness of JVMState::debug_xxx accessors:
1093 assert(call->jvms()->debug_start() == non_debug_edges, "");
1094 assert(call->jvms()->debug_end() == call->req(), "");
1095 assert(call->jvms()->debug_depth() == call->req() - non_debug_edges, "");
1096 }
1097
1098 bool GraphKit::compute_stack_effects(int& inputs, int& depth) {
1099 Bytecodes::Code code = java_bc();
1100 if (code == Bytecodes::_wide) {
1101 code = method()->java_code_at_bci(bci() + 1);
1102 }
1103
1104 if (code != Bytecodes::_illegal) {
1105 depth = Bytecodes::depth(code); // checkcast=0, athrow=-1
1106 }
1107
1108 auto rsize = [&]() {
1109 assert(code != Bytecodes::_illegal, "code is illegal!");
1110 BasicType rtype = Bytecodes::result_type(code); // checkcast=P, athrow=V
1111 return (rtype < T_CONFLICT) ? type2size[rtype] : 0;
1112 };
1113
1114 switch (code) {
1115 case Bytecodes::_illegal:
1116 return false;
1117
1118 case Bytecodes::_ldc:
1119 case Bytecodes::_ldc_w:
1120 case Bytecodes::_ldc2_w:
1121 inputs = 0;
1122 break;
1123
1124 case Bytecodes::_dup: inputs = 1; break;
1125 case Bytecodes::_dup_x1: inputs = 2; break;
1126 case Bytecodes::_dup_x2: inputs = 3; break;
1127 case Bytecodes::_dup2: inputs = 2; break;
1128 case Bytecodes::_dup2_x1: inputs = 3; break;
1129 case Bytecodes::_dup2_x2: inputs = 4; break;
1130 case Bytecodes::_swap: inputs = 2; break;
1131 case Bytecodes::_arraylength: inputs = 1; break;
1132
1133 case Bytecodes::_getstatic:
1134 case Bytecodes::_putstatic:
1135 case Bytecodes::_getfield:
1136 case Bytecodes::_putfield:
1137 {
1138 bool ignored_will_link;
1139 ciField* field = method()->get_field_at_bci(bci(), ignored_will_link);
1140 int size = field->type()->size();
1141 bool is_get = (depth >= 0), is_static = (depth & 1);
1142 inputs = (is_static ? 0 : 1);
1143 if (is_get) {
1144 depth = size - inputs;
1145 } else {
1146 inputs += size; // putxxx pops the value from the stack
1147 depth = - inputs;
1148 }
1149 }
1150 break;
1151
1152 case Bytecodes::_invokevirtual:
1153 case Bytecodes::_invokespecial:
1154 case Bytecodes::_invokestatic:
1155 case Bytecodes::_invokedynamic:
1156 case Bytecodes::_invokeinterface:
1157 {
1158 bool ignored_will_link;
1159 ciSignature* declared_signature = nullptr;
1160 ciMethod* ignored_callee = method()->get_method_at_bci(bci(), ignored_will_link, &declared_signature);
1161 assert(declared_signature != nullptr, "cannot be null");
1162 inputs = declared_signature->arg_size_for_bc(code);
1163 int size = declared_signature->return_type()->size();
1164 depth = size - inputs;
1165 }
1166 break;
1167
1168 case Bytecodes::_multianewarray:
1169 {
1170 ciBytecodeStream iter(method());
1171 iter.reset_to_bci(bci());
1172 iter.next();
1173 inputs = iter.get_dimensions();
1174 assert(rsize() == 1, "");
1175 depth = 1 - inputs;
1176 }
1177 break;
1178
1179 case Bytecodes::_ireturn:
1180 case Bytecodes::_lreturn:
1181 case Bytecodes::_freturn:
1182 case Bytecodes::_dreturn:
1183 case Bytecodes::_areturn:
1184 assert(rsize() == -depth, "");
1185 inputs = -depth;
1186 break;
1187
1188 case Bytecodes::_jsr:
1189 case Bytecodes::_jsr_w:
1190 inputs = 0;
1191 depth = 1; // S.B. depth=1, not zero
1192 break;
1193
1194 default:
1195 // bytecode produces a typed result
1196 inputs = rsize() - depth;
1197 assert(inputs >= 0, "");
1198 break;
1199 }
1200
1201 #ifdef ASSERT
1202 // spot check
1203 int outputs = depth + inputs;
1204 assert(outputs >= 0, "sanity");
1205 switch (code) {
1206 case Bytecodes::_checkcast: assert(inputs == 1 && outputs == 1, ""); break;
1207 case Bytecodes::_athrow: assert(inputs == 1 && outputs == 0, ""); break;
1208 case Bytecodes::_aload_0: assert(inputs == 0 && outputs == 1, ""); break;
1209 case Bytecodes::_return: assert(inputs == 0 && outputs == 0, ""); break;
1210 case Bytecodes::_drem: assert(inputs == 4 && outputs == 2, ""); break;
1211 default: break;
1212 }
1213 #endif //ASSERT
1214
1215 return true;
1216 }
1217
1218
1219
1220 //------------------------------basic_plus_adr---------------------------------
1221 Node* GraphKit::basic_plus_adr(Node* base, Node* ptr, Node* offset) {
1222 // short-circuit a common case
1223 if (offset == MakeConX(0)) {
1224 return ptr;
1225 }
1226 #ifdef ASSERT
1227 // Both 32-bit and 64-bit zeros should have been handled by the previous `if`
1228 // statement, so if we see either 32-bit or 64-bit zeros here, then we have a
1229 // problem.
1230 if (offset->is_Con()) {
1231 const Type* t = offset->bottom_type();
1232 bool is_zero_int = t->isa_int() && t->is_int()->get_con() == 0;
1233 bool is_zero_long = t->isa_long() && t->is_long()->get_con() == 0;
1234 assert(!is_zero_int && !is_zero_long,
1235 "Unexpected zero offset - should have matched MakeConX(0)");
1236 }
1237 #endif
1238 return _gvn.transform(AddPNode::make_with_base(base, ptr, offset));
1239 }
1240
1241 Node* GraphKit::ConvI2L(Node* offset) {
1242 // short-circuit a common case
1243 jint offset_con = find_int_con(offset, Type::OffsetBot);
1244 if (offset_con != Type::OffsetBot) {
1245 return longcon((jlong) offset_con);
1246 }
1247 return _gvn.transform( new ConvI2LNode(offset));
1248 }
1249
1250 Node* GraphKit::ConvI2UL(Node* offset) {
1251 juint offset_con = (juint) find_int_con(offset, Type::OffsetBot);
1252 if (offset_con != (juint) Type::OffsetBot) {
1253 return longcon((julong) offset_con);
1254 }
1255 Node* conv = _gvn.transform( new ConvI2LNode(offset));
1256 Node* mask = _gvn.transform(ConLNode::make((julong) max_juint));
1257 return _gvn.transform( new AndLNode(conv, mask) );
1258 }
1259
1260 Node* GraphKit::ConvL2I(Node* offset) {
1261 // short-circuit a common case
1262 jlong offset_con = find_long_con(offset, (jlong)Type::OffsetBot);
1263 if (offset_con != (jlong)Type::OffsetBot) {
1264 return intcon((int) offset_con);
1265 }
1266 return _gvn.transform( new ConvL2INode(offset));
1267 }
1268
1269 //-------------------------load_object_klass-----------------------------------
1270 Node* GraphKit::load_object_klass(Node* obj) {
1271 // Special-case a fresh allocation to avoid building nodes:
1272 Node* akls = AllocateNode::Ideal_klass(obj, &_gvn);
1273 if (akls != nullptr) return akls;
1274 Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes());
1275 return _gvn.transform(LoadKlassNode::make(_gvn, immutable_memory(), k_adr, TypeInstPtr::KLASS));
1276 }
1277
1278 //-------------------------load_array_length-----------------------------------
1279 Node* GraphKit::load_array_length(Node* array) {
1280 // Special-case a fresh allocation to avoid building nodes:
1281 AllocateArrayNode* alloc = AllocateArrayNode::Ideal_array_allocation(array);
1282 Node *alen;
1283 if (alloc == nullptr) {
1284 Node *r_adr = basic_plus_adr(array, arrayOopDesc::length_offset_in_bytes());
1285 alen = _gvn.transform( new LoadRangeNode(nullptr, immutable_memory(), r_adr, TypeInt::POS));
1286 } else {
1287 alen = array_ideal_length(alloc, _gvn.type(array)->is_oopptr(), false);
1288 }
1289 return alen;
1290 }
1291
1292 Node* GraphKit::array_ideal_length(AllocateArrayNode* alloc,
1293 const TypeOopPtr* oop_type,
1294 bool replace_length_in_map) {
1295 Node* length = alloc->Ideal_length();
1296 if (replace_length_in_map == false || map()->find_edge(length) >= 0) {
1297 Node* ccast = alloc->make_ideal_length(oop_type, &_gvn);
1298 if (ccast != length) {
1299 // do not transform ccast here, it might convert to top node for
1300 // negative array length and break assumptions in parsing stage.
1301 _gvn.set_type_bottom(ccast);
1302 record_for_igvn(ccast);
1303 if (replace_length_in_map) {
1304 replace_in_map(length, ccast);
1305 }
1306 return ccast;
1307 }
1308 }
1309 return length;
1310 }
1311
1312 //------------------------------do_null_check----------------------------------
1313 // Helper function to do a null pointer check. Returned value is
1314 // the incoming address with null casted away. You are allowed to use the
1315 // not-null value only if you are control dependent on the test.
1316 #ifndef PRODUCT
1317 extern uint explicit_null_checks_inserted,
1318 explicit_null_checks_elided;
1319 #endif
1320 Node* GraphKit::null_check_common(Node* value, BasicType type,
1321 // optional arguments for variations:
1322 bool assert_null,
1323 Node* *null_control,
1324 bool speculative) {
1325 assert(!assert_null || null_control == nullptr, "not both at once");
1326 if (stopped()) return top();
1327 NOT_PRODUCT(explicit_null_checks_inserted++);
1328
1329 // Construct null check
1330 Node *chk = nullptr;
1331 switch(type) {
1332 case T_LONG : chk = new CmpLNode(value, _gvn.zerocon(T_LONG)); break;
1333 case T_INT : chk = new CmpINode(value, _gvn.intcon(0)); break;
1334 case T_ARRAY : // fall through
1335 type = T_OBJECT; // simplify further tests
1336 case T_OBJECT : {
1337 const Type *t = _gvn.type( value );
1338
1339 const TypeOopPtr* tp = t->isa_oopptr();
1340 if (tp != nullptr && !tp->is_loaded()
1341 // Only for do_null_check, not any of its siblings:
1342 && !assert_null && null_control == nullptr) {
1343 // Usually, any field access or invocation on an unloaded oop type
1344 // will simply fail to link, since the statically linked class is
1345 // likely also to be unloaded. However, in -Xcomp mode, sometimes
1346 // the static class is loaded but the sharper oop type is not.
1347 // Rather than checking for this obscure case in lots of places,
1348 // we simply observe that a null check on an unloaded class
1349 // will always be followed by a nonsense operation, so we
1350 // can just issue the uncommon trap here.
1351 // Our access to the unloaded class will only be correct
1352 // after it has been loaded and initialized, which requires
1353 // a trip through the interpreter.
1354 ciKlass* klass = tp->unloaded_klass();
1355 #ifndef PRODUCT
1356 if (WizardMode) { tty->print("Null check of unloaded "); klass->print(); tty->cr(); }
1357 #endif
1358 uncommon_trap(Deoptimization::Reason_unloaded,
1359 Deoptimization::Action_reinterpret,
1360 klass, "!loaded");
1361 return top();
1362 }
1363
1364 if (assert_null) {
1365 // See if the type is contained in NULL_PTR.
1366 // If so, then the value is already null.
1367 if (t->higher_equal(TypePtr::NULL_PTR)) {
1368 NOT_PRODUCT(explicit_null_checks_elided++);
1369 return value; // Elided null assert quickly!
1370 }
1371 } else {
1372 // See if mixing in the null pointer changes type.
1373 // If so, then the null pointer was not allowed in the original
1374 // type. In other words, "value" was not-null.
1375 if (t->meet(TypePtr::NULL_PTR) != t->remove_speculative()) {
1376 // same as: if (!TypePtr::NULL_PTR->higher_equal(t)) ...
1377 NOT_PRODUCT(explicit_null_checks_elided++);
1378 return value; // Elided null check quickly!
1379 }
1380 }
1381 chk = new CmpPNode( value, null() );
1382 break;
1383 }
1384
1385 default:
1386 fatal("unexpected type: %s", type2name(type));
1387 }
1388 assert(chk != nullptr, "sanity check");
1389 chk = _gvn.transform(chk);
1390
1391 BoolTest::mask btest = assert_null ? BoolTest::eq : BoolTest::ne;
1392 BoolNode *btst = new BoolNode( chk, btest);
1393 Node *tst = _gvn.transform( btst );
1394
1395 //-----------
1396 // if peephole optimizations occurred, a prior test existed.
1397 // If a prior test existed, maybe it dominates as we can avoid this test.
1398 if (tst != btst && type == T_OBJECT) {
1399 // At this point we want to scan up the CFG to see if we can
1400 // find an identical test (and so avoid this test altogether).
1401 Node *cfg = control();
1402 int depth = 0;
1403 while( depth < 16 ) { // Limit search depth for speed
1404 if( cfg->Opcode() == Op_IfTrue &&
1405 cfg->in(0)->in(1) == tst ) {
1406 // Found prior test. Use "cast_not_null" to construct an identical
1407 // CastPP (and hence hash to) as already exists for the prior test.
1408 // Return that casted value.
1409 if (assert_null) {
1410 replace_in_map(value, null());
1411 return null(); // do not issue the redundant test
1412 }
1413 Node *oldcontrol = control();
1414 set_control(cfg);
1415 Node *res = cast_not_null(value);
1416 set_control(oldcontrol);
1417 NOT_PRODUCT(explicit_null_checks_elided++);
1418 return res;
1419 }
1420 cfg = IfNode::up_one_dom(cfg, /*linear_only=*/ true);
1421 if (cfg == nullptr) break; // Quit at region nodes
1422 depth++;
1423 }
1424 }
1425
1426 //-----------
1427 // Branch to failure if null
1428 float ok_prob = PROB_MAX; // a priori estimate: nulls never happen
1429 Deoptimization::DeoptReason reason;
1430 if (assert_null) {
1431 reason = Deoptimization::reason_null_assert(speculative);
1432 } else if (type == T_OBJECT) {
1433 reason = Deoptimization::reason_null_check(speculative);
1434 } else {
1435 reason = Deoptimization::Reason_div0_check;
1436 }
1437 // %%% Since Reason_unhandled is not recorded on a per-bytecode basis,
1438 // ciMethodData::has_trap_at will return a conservative -1 if any
1439 // must-be-null assertion has failed. This could cause performance
1440 // problems for a method after its first do_null_assert failure.
1441 // Consider using 'Reason_class_check' instead?
1442
1443 // To cause an implicit null check, we set the not-null probability
1444 // to the maximum (PROB_MAX). For an explicit check the probability
1445 // is set to a smaller value.
1446 if (null_control != nullptr || too_many_traps(reason)) {
1447 // probability is less likely
1448 ok_prob = PROB_LIKELY_MAG(3);
1449 } else if (!assert_null &&
1450 (ImplicitNullCheckThreshold > 0) &&
1451 method() != nullptr &&
1452 (method()->method_data()->trap_count(reason)
1453 >= (uint)ImplicitNullCheckThreshold)) {
1454 ok_prob = PROB_LIKELY_MAG(3);
1455 }
1456
1457 if (null_control != nullptr) {
1458 IfNode* iff = create_and_map_if(control(), tst, ok_prob, COUNT_UNKNOWN);
1459 Node* null_true = _gvn.transform( new IfFalseNode(iff));
1460 set_control( _gvn.transform( new IfTrueNode(iff)));
1461 #ifndef PRODUCT
1462 if (null_true == top()) {
1463 explicit_null_checks_elided++;
1464 }
1465 #endif
1466 (*null_control) = null_true;
1467 } else {
1468 BuildCutout unless(this, tst, ok_prob);
1469 // Check for optimizer eliding test at parse time
1470 if (stopped()) {
1471 // Failure not possible; do not bother making uncommon trap.
1472 NOT_PRODUCT(explicit_null_checks_elided++);
1473 } else if (assert_null) {
1474 uncommon_trap(reason,
1475 Deoptimization::Action_make_not_entrant,
1476 nullptr, "assert_null");
1477 } else {
1478 replace_in_map(value, zerocon(type));
1479 builtin_throw(reason);
1480 }
1481 }
1482
1483 // Must throw exception, fall-thru not possible?
1484 if (stopped()) {
1485 return top(); // No result
1486 }
1487
1488 if (assert_null) {
1489 // Cast obj to null on this path.
1490 replace_in_map(value, zerocon(type));
1491 return zerocon(type);
1492 }
1493
1494 // Cast obj to not-null on this path, if there is no null_control.
1495 // (If there is a null_control, a non-null value may come back to haunt us.)
1496 if (type == T_OBJECT) {
1497 Node* cast = cast_not_null(value, false);
1498 if (null_control == nullptr || (*null_control) == top())
1499 replace_in_map(value, cast);
1500 value = cast;
1501 }
1502
1503 return value;
1504 }
1505
1506
1507 //------------------------------cast_not_null----------------------------------
1508 // Cast obj to not-null on this path
1509 Node* GraphKit::cast_not_null(Node* obj, bool do_replace_in_map) {
1510 const Type *t = _gvn.type(obj);
1511 const Type *t_not_null = t->join_speculative(TypePtr::NOTNULL);
1512 // Object is already not-null?
1513 if( t == t_not_null ) return obj;
1514
1515 Node* cast = new CastPPNode(control(), obj,t_not_null);
1516 cast = _gvn.transform( cast );
1517
1518 // Scan for instances of 'obj' in the current JVM mapping.
1519 // These instances are known to be not-null after the test.
1520 if (do_replace_in_map)
1521 replace_in_map(obj, cast);
1522
1523 return cast; // Return casted value
1524 }
1525
1526 // Sometimes in intrinsics, we implicitly know an object is not null
1527 // (there's no actual null check) so we can cast it to not null. In
1528 // the course of optimizations, the input to the cast can become null.
1529 // In that case that data path will die and we need the control path
1530 // to become dead as well to keep the graph consistent. So we have to
1531 // add a check for null for which one branch can't be taken. It uses
1532 // an OpaqueConstantBool node that will cause the check to be removed after loop
1533 // opts so the test goes away and the compiled code doesn't execute a
1534 // useless check.
1535 Node* GraphKit::must_be_not_null(Node* value, bool do_replace_in_map) {
1536 if (!TypePtr::NULL_PTR->higher_equal(_gvn.type(value))) {
1537 return value;
1538 }
1539 Node* chk = _gvn.transform(new CmpPNode(value, null()));
1540 Node* tst = _gvn.transform(new BoolNode(chk, BoolTest::ne));
1541 Node* opaq = _gvn.transform(new OpaqueConstantBoolNode(C, tst, true));
1542 IfNode* iff = new IfNode(control(), opaq, PROB_MAX, COUNT_UNKNOWN);
1543 _gvn.set_type(iff, iff->Value(&_gvn));
1544 if (!tst->is_Con()) {
1545 record_for_igvn(iff);
1546 }
1547 Node *if_f = _gvn.transform(new IfFalseNode(iff));
1548 Node *frame = _gvn.transform(new ParmNode(C->start(), TypeFunc::FramePtr));
1549 halt(if_f, frame, "unexpected null in intrinsic");
1550 Node *if_t = _gvn.transform(new IfTrueNode(iff));
1551 set_control(if_t);
1552 return cast_not_null(value, do_replace_in_map);
1553 }
1554
1555
1556 //--------------------------replace_in_map-------------------------------------
1557 void GraphKit::replace_in_map(Node* old, Node* neww) {
1558 if (old == neww) {
1559 return;
1560 }
1561
1562 map()->replace_edge(old, neww);
1563
1564 // Note: This operation potentially replaces any edge
1565 // on the map. This includes locals, stack, and monitors
1566 // of the current (innermost) JVM state.
1567
1568 // don't let inconsistent types from profiling escape this
1569 // method
1570
1571 const Type* told = _gvn.type(old);
1572 const Type* tnew = _gvn.type(neww);
1573
1574 if (!tnew->higher_equal(told)) {
1575 return;
1576 }
1577
1578 map()->record_replaced_node(old, neww);
1579 }
1580
1581
1582 //=============================================================================
1583 //--------------------------------memory---------------------------------------
1584 Node* GraphKit::memory(uint alias_idx) {
1585 MergeMemNode* mem = merged_memory();
1586 Node* p = mem->memory_at(alias_idx);
1587 assert(p != mem->empty_memory(), "empty");
1588 _gvn.set_type(p, Type::MEMORY); // must be mapped
1589 return p;
1590 }
1591
1592 //-----------------------------reset_memory------------------------------------
1593 Node* GraphKit::reset_memory() {
1594 Node* mem = map()->memory();
1595 // do not use this node for any more parsing!
1596 DEBUG_ONLY( map()->set_memory((Node*)nullptr) );
1597 return _gvn.transform( mem );
1598 }
1599
1600 //------------------------------set_all_memory---------------------------------
1601 void GraphKit::set_all_memory(Node* newmem) {
1602 Node* mergemem = MergeMemNode::make(newmem);
1603 gvn().set_type_bottom(mergemem);
1604 map()->set_memory(mergemem);
1605 }
1606
1607 //------------------------------set_all_memory_call----------------------------
1608 void GraphKit::set_all_memory_call(Node* call, bool separate_io_proj) {
1609 Node* newmem = _gvn.transform( new ProjNode(call, TypeFunc::Memory, separate_io_proj) );
1610 set_all_memory(newmem);
1611 }
1612
1613 //=============================================================================
1614 //
1615 // parser factory methods for MemNodes
1616 //
1617 // These are layered on top of the factory methods in LoadNode and StoreNode,
1618 // and integrate with the parser's memory state and _gvn engine.
1619 //
1620
1621 // factory methods in "int adr_idx"
1622 Node* GraphKit::make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
1623 MemNode::MemOrd mo,
1624 LoadNode::ControlDependency control_dependency,
1625 bool require_atomic_access,
1626 bool unaligned,
1627 bool mismatched,
1628 bool unsafe,
1629 uint8_t barrier_data) {
1630 int adr_idx = C->get_alias_index(_gvn.type(adr)->isa_ptr());
1631 assert(adr_idx != Compile::AliasIdxTop, "use other make_load factory" );
1632 const TypePtr* adr_type = nullptr; // debug-mode-only argument
1633 DEBUG_ONLY(adr_type = C->get_adr_type(adr_idx));
1634 Node* mem = memory(adr_idx);
1635 Node* ld = LoadNode::make(_gvn, ctl, mem, adr, adr_type, t, bt, mo, control_dependency, require_atomic_access, unaligned, mismatched, unsafe, barrier_data);
1636 ld = _gvn.transform(ld);
1637 if (((bt == T_OBJECT) && C->do_escape_analysis()) || C->eliminate_boxing()) {
1638 // Improve graph before escape analysis and boxing elimination.
1639 record_for_igvn(ld);
1640 if (ld->is_DecodeN()) {
1641 // Also record the actual load (LoadN) in case ld is DecodeN. In some
1642 // rare corner cases, ld->in(1) can be something other than LoadN (e.g.,
1643 // a Phi). Recording such cases is still perfectly sound, but may be
1644 // unnecessary and result in some minor IGVN overhead.
1645 record_for_igvn(ld->in(1));
1646 }
1647 }
1648 return ld;
1649 }
1650
1651 Node* GraphKit::store_to_memory(Node* ctl, Node* adr, Node *val, BasicType bt,
1652 MemNode::MemOrd mo,
1653 bool require_atomic_access,
1654 bool unaligned,
1655 bool mismatched,
1656 bool unsafe,
1657 int barrier_data) {
1658 int adr_idx = C->get_alias_index(_gvn.type(adr)->isa_ptr());
1659 assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1660 const TypePtr* adr_type = nullptr;
1661 DEBUG_ONLY(adr_type = C->get_adr_type(adr_idx));
1662 Node *mem = memory(adr_idx);
1663 Node* st = StoreNode::make(_gvn, ctl, mem, adr, adr_type, val, bt, mo, require_atomic_access);
1664 if (unaligned) {
1665 st->as_Store()->set_unaligned_access();
1666 }
1667 if (mismatched) {
1668 st->as_Store()->set_mismatched_access();
1669 }
1670 if (unsafe) {
1671 st->as_Store()->set_unsafe_access();
1672 }
1673 st->as_Store()->set_barrier_data(barrier_data);
1674 st = _gvn.transform(st);
1675 set_memory(st, adr_idx);
1676 // Back-to-back stores can only remove intermediate store with DU info
1677 // so push on worklist for optimizer.
1678 if (mem->req() > MemNode::Address && adr == mem->in(MemNode::Address))
1679 record_for_igvn(st);
1680
1681 return st;
1682 }
1683
1684 Node* GraphKit::access_store_at(Node* obj,
1685 Node* adr,
1686 const TypePtr* adr_type,
1687 Node* val,
1688 const Type* val_type,
1689 BasicType bt,
1690 DecoratorSet decorators) {
1691 // Transformation of a value which could be null pointer (CastPP #null)
1692 // could be delayed during Parse (for example, in adjust_map_after_if()).
1693 // Execute transformation here to avoid barrier generation in such case.
1694 if (_gvn.type(val) == TypePtr::NULL_PTR) {
1695 val = _gvn.makecon(TypePtr::NULL_PTR);
1696 }
1697
1698 if (stopped()) {
1699 return top(); // Dead path ?
1700 }
1701
1702 assert(val != nullptr, "not dead path");
1703
1704 C2AccessValuePtr addr(adr, adr_type);
1705 C2AccessValue value(val, val_type);
1706 C2ParseAccess access(this, decorators | C2_WRITE_ACCESS, bt, obj, addr);
1707 if (access.is_raw()) {
1708 return _barrier_set->BarrierSetC2::store_at(access, value);
1709 } else {
1710 return _barrier_set->store_at(access, value);
1711 }
1712 }
1713
1714 Node* GraphKit::access_load_at(Node* obj, // containing obj
1715 Node* adr, // actual address to store val at
1716 const TypePtr* adr_type,
1717 const Type* val_type,
1718 BasicType bt,
1719 DecoratorSet decorators) {
1720 if (stopped()) {
1721 return top(); // Dead path ?
1722 }
1723
1724 SavedState old_state(this);
1725 C2AccessValuePtr addr(adr, adr_type);
1726 C2ParseAccess access(this, decorators | C2_READ_ACCESS, bt, obj, addr);
1727 Node* load;
1728 if (access.is_raw()) {
1729 load = _barrier_set->BarrierSetC2::load_at(access, val_type);
1730 } else {
1731 load = _barrier_set->load_at(access, val_type);
1732 }
1733
1734 // Restore the previous state only if the load got folded to a constant
1735 // and we can discard any barriers that might have been added.
1736 if (load == nullptr || !load->is_Con()) {
1737 old_state.discard();
1738 }
1739 return load;
1740 }
1741
1742 Node* GraphKit::access_load(Node* adr, // actual address to load val at
1743 const Type* val_type,
1744 BasicType bt,
1745 DecoratorSet decorators) {
1746 if (stopped()) {
1747 return top(); // Dead path ?
1748 }
1749
1750 SavedState old_state(this);
1751 C2AccessValuePtr addr(adr, adr->bottom_type()->is_ptr());
1752 C2ParseAccess access(this, decorators | C2_READ_ACCESS, bt, nullptr, addr);
1753 Node* load;
1754 if (access.is_raw()) {
1755 load = _barrier_set->BarrierSetC2::load_at(access, val_type);
1756 } else {
1757 load = _barrier_set->load_at(access, val_type);
1758 }
1759
1760 // Restore the previous state only if the load got folded to a constant
1761 // and we can discard any barriers that might have been added.
1762 if (load == nullptr || !load->is_Con()) {
1763 old_state.discard();
1764 }
1765 return load;
1766 }
1767
1768 Node* GraphKit::access_atomic_cmpxchg_val_at(Node* obj,
1769 Node* adr,
1770 const TypePtr* adr_type,
1771 int alias_idx,
1772 Node* expected_val,
1773 Node* new_val,
1774 const Type* value_type,
1775 BasicType bt,
1776 DecoratorSet decorators) {
1777 C2AccessValuePtr addr(adr, adr_type);
1778 C2AtomicParseAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS,
1779 bt, obj, addr, alias_idx);
1780 if (access.is_raw()) {
1781 return _barrier_set->BarrierSetC2::atomic_cmpxchg_val_at(access, expected_val, new_val, value_type);
1782 } else {
1783 return _barrier_set->atomic_cmpxchg_val_at(access, expected_val, new_val, value_type);
1784 }
1785 }
1786
1787 Node* GraphKit::access_atomic_cmpxchg_bool_at(Node* obj,
1788 Node* adr,
1789 const TypePtr* adr_type,
1790 int alias_idx,
1791 Node* expected_val,
1792 Node* new_val,
1793 const Type* value_type,
1794 BasicType bt,
1795 DecoratorSet decorators) {
1796 C2AccessValuePtr addr(adr, adr_type);
1797 C2AtomicParseAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS,
1798 bt, obj, addr, alias_idx);
1799 if (access.is_raw()) {
1800 return _barrier_set->BarrierSetC2::atomic_cmpxchg_bool_at(access, expected_val, new_val, value_type);
1801 } else {
1802 return _barrier_set->atomic_cmpxchg_bool_at(access, expected_val, new_val, value_type);
1803 }
1804 }
1805
1806 Node* GraphKit::access_atomic_xchg_at(Node* obj,
1807 Node* adr,
1808 const TypePtr* adr_type,
1809 int alias_idx,
1810 Node* new_val,
1811 const Type* value_type,
1812 BasicType bt,
1813 DecoratorSet decorators) {
1814 C2AccessValuePtr addr(adr, adr_type);
1815 C2AtomicParseAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS,
1816 bt, obj, addr, alias_idx);
1817 if (access.is_raw()) {
1818 return _barrier_set->BarrierSetC2::atomic_xchg_at(access, new_val, value_type);
1819 } else {
1820 return _barrier_set->atomic_xchg_at(access, new_val, value_type);
1821 }
1822 }
1823
1824 Node* GraphKit::access_atomic_add_at(Node* obj,
1825 Node* adr,
1826 const TypePtr* adr_type,
1827 int alias_idx,
1828 Node* new_val,
1829 const Type* value_type,
1830 BasicType bt,
1831 DecoratorSet decorators) {
1832 C2AccessValuePtr addr(adr, adr_type);
1833 C2AtomicParseAccess access(this, decorators | C2_READ_ACCESS | C2_WRITE_ACCESS, bt, obj, addr, alias_idx);
1834 if (access.is_raw()) {
1835 return _barrier_set->BarrierSetC2::atomic_add_at(access, new_val, value_type);
1836 } else {
1837 return _barrier_set->atomic_add_at(access, new_val, value_type);
1838 }
1839 }
1840
1841 void GraphKit::access_clone(Node* src, Node* dst, Node* size, bool is_array) {
1842 return _barrier_set->clone(this, src, dst, size, is_array);
1843 }
1844
1845 //-------------------------array_element_address-------------------------
1846 Node* GraphKit::array_element_address(Node* ary, Node* idx, BasicType elembt,
1847 const TypeInt* sizetype, Node* ctrl) {
1848 uint shift = exact_log2(type2aelembytes(elembt));
1849 uint header = arrayOopDesc::base_offset_in_bytes(elembt);
1850
1851 // short-circuit a common case (saves lots of confusing waste motion)
1852 jint idx_con = find_int_con(idx, -1);
1853 if (idx_con >= 0) {
1854 intptr_t offset = header + ((intptr_t)idx_con << shift);
1855 return basic_plus_adr(ary, offset);
1856 }
1857
1858 // must be correct type for alignment purposes
1859 Node* base = basic_plus_adr(ary, header);
1860 idx = Compile::conv_I2X_index(&_gvn, idx, sizetype, ctrl);
1861 Node* scale = _gvn.transform( new LShiftXNode(idx, intcon(shift)) );
1862 return basic_plus_adr(ary, base, scale);
1863 }
1864
1865 //-------------------------load_array_element-------------------------
1866 Node* GraphKit::load_array_element(Node* ary, Node* idx, const TypeAryPtr* arytype, bool set_ctrl) {
1867 const Type* elemtype = arytype->elem();
1868 BasicType elembt = elemtype->array_element_basic_type();
1869 Node* adr = array_element_address(ary, idx, elembt, arytype->size());
1870 if (elembt == T_NARROWOOP) {
1871 elembt = T_OBJECT; // To satisfy switch in LoadNode::make()
1872 }
1873 Node* ld = access_load_at(ary, adr, arytype, elemtype, elembt,
1874 IN_HEAP | IS_ARRAY | (set_ctrl ? C2_CONTROL_DEPENDENT_LOAD : 0));
1875 return ld;
1876 }
1877
1878 //-------------------------set_arguments_for_java_call-------------------------
1879 // Arguments (pre-popped from the stack) are taken from the JVMS.
1880 void GraphKit::set_arguments_for_java_call(CallJavaNode* call) {
1881 // Add the call arguments:
1882 uint nargs = call->method()->arg_size();
1883 for (uint i = 0; i < nargs; i++) {
1884 Node* arg = argument(i);
1885 call->init_req(i + TypeFunc::Parms, arg);
1886 }
1887 }
1888
1889 //---------------------------set_edges_for_java_call---------------------------
1890 // Connect a newly created call into the current JVMS.
1891 // A return value node (if any) is returned from set_edges_for_java_call.
1892 void GraphKit::set_edges_for_java_call(CallJavaNode* call, bool must_throw, bool separate_io_proj) {
1893
1894 // Add the predefined inputs:
1895 call->init_req( TypeFunc::Control, control() );
1896 call->init_req( TypeFunc::I_O , i_o() );
1897 call->init_req( TypeFunc::Memory , reset_memory() );
1898 call->init_req( TypeFunc::FramePtr, frameptr() );
1899 call->init_req( TypeFunc::ReturnAdr, top() );
1900
1901 add_safepoint_edges(call, must_throw);
1902
1903 Node* xcall = _gvn.transform(call);
1904
1905 if (xcall == top()) {
1906 set_control(top());
1907 return;
1908 }
1909 assert(xcall == call, "call identity is stable");
1910
1911 // Re-use the current map to produce the result.
1912
1913 set_control(_gvn.transform(new ProjNode(call, TypeFunc::Control)));
1914 set_i_o( _gvn.transform(new ProjNode(call, TypeFunc::I_O , separate_io_proj)));
1915 set_all_memory_call(xcall, separate_io_proj);
1916
1917 //return xcall; // no need, caller already has it
1918 }
1919
1920 Node* GraphKit::set_results_for_java_call(CallJavaNode* call, bool separate_io_proj, bool deoptimize) {
1921 if (stopped()) return top(); // maybe the call folded up?
1922
1923 // Capture the return value, if any.
1924 Node* ret;
1925 if (call->method() == nullptr ||
1926 call->method()->return_type()->basic_type() == T_VOID)
1927 ret = top();
1928 else ret = _gvn.transform(new ProjNode(call, TypeFunc::Parms));
1929
1930 // Note: Since any out-of-line call can produce an exception,
1931 // we always insert an I_O projection from the call into the result.
1932
1933 make_slow_call_ex(call, env()->Throwable_klass(), separate_io_proj, deoptimize);
1934
1935 if (separate_io_proj) {
1936 // The caller requested separate projections be used by the fall
1937 // through and exceptional paths, so replace the projections for
1938 // the fall through path.
1939 set_i_o(_gvn.transform( new ProjNode(call, TypeFunc::I_O) ));
1940 set_all_memory(_gvn.transform( new ProjNode(call, TypeFunc::Memory) ));
1941 }
1942 return ret;
1943 }
1944
1945 //--------------------set_predefined_input_for_runtime_call--------------------
1946 // Reading and setting the memory state is way conservative here.
1947 // The real problem is that I am not doing real Type analysis on memory,
1948 // so I cannot distinguish card mark stores from other stores. Across a GC
1949 // point the Store Barrier and the card mark memory has to agree. I cannot
1950 // have a card mark store and its barrier split across the GC point from
1951 // either above or below. Here I get that to happen by reading ALL of memory.
1952 // A better answer would be to separate out card marks from other memory.
1953 // For now, return the input memory state, so that it can be reused
1954 // after the call, if this call has restricted memory effects.
1955 Node* GraphKit::set_predefined_input_for_runtime_call(SafePointNode* call, Node* narrow_mem) {
1956 // Set fixed predefined input arguments
1957 call->init_req(TypeFunc::Control, control());
1958 call->init_req(TypeFunc::I_O, top()); // does no i/o
1959 call->init_req(TypeFunc::ReturnAdr, top());
1960 if (call->is_CallLeafPure()) {
1961 call->init_req(TypeFunc::Memory, top());
1962 call->init_req(TypeFunc::FramePtr, top());
1963 return nullptr;
1964 } else {
1965 Node* memory = reset_memory();
1966 Node* m = narrow_mem == nullptr ? memory : narrow_mem;
1967 call->init_req(TypeFunc::Memory, m); // may gc ptrs
1968 call->init_req(TypeFunc::FramePtr, frameptr());
1969 return memory;
1970 }
1971 }
1972
1973 //-------------------set_predefined_output_for_runtime_call--------------------
1974 // Set control and memory (not i_o) from the call.
1975 // If keep_mem is not null, use it for the output state,
1976 // except for the RawPtr output of the call, if hook_mem is TypeRawPtr::BOTTOM.
1977 // If hook_mem is null, this call produces no memory effects at all.
1978 // If hook_mem is a Java-visible memory slice (such as arraycopy operands),
1979 // then only that memory slice is taken from the call.
1980 // In the last case, we must put an appropriate memory barrier before
1981 // the call, so as to create the correct anti-dependencies on loads
1982 // preceding the call.
1983 void GraphKit::set_predefined_output_for_runtime_call(Node* call,
1984 Node* keep_mem,
1985 const TypePtr* hook_mem) {
1986 // no i/o
1987 set_control(_gvn.transform( new ProjNode(call,TypeFunc::Control) ));
1988 if (call->is_CallLeafPure()) {
1989 // Pure function have only control (for now) and data output, in particular
1990 // they don't touch the memory, so we don't want a memory proj that is set after.
1991 return;
1992 }
1993 if (keep_mem) {
1994 // First clone the existing memory state
1995 set_all_memory(keep_mem);
1996 if (hook_mem != nullptr) {
1997 // Make memory for the call
1998 Node* mem = _gvn.transform( new ProjNode(call, TypeFunc::Memory) );
1999 // Set the RawPtr memory state only. This covers all the heap top/GC stuff
2000 // We also use hook_mem to extract specific effects from arraycopy stubs.
2001 set_memory(mem, hook_mem);
2002 }
2003 // ...else the call has NO memory effects.
2004
2005 // Make sure the call advertises its memory effects precisely.
2006 // This lets us build accurate anti-dependences in gcm.cpp.
2007 assert(C->alias_type(call->adr_type()) == C->alias_type(hook_mem),
2008 "call node must be constructed correctly");
2009 } else {
2010 assert(hook_mem == nullptr, "");
2011 // This is not a "slow path" call; all memory comes from the call.
2012 set_all_memory_call(call);
2013 }
2014 }
2015
2016 // Keep track of MergeMems feeding into other MergeMems
2017 static void add_mergemem_users_to_worklist(Unique_Node_List& wl, Node* mem) {
2018 if (!mem->is_MergeMem()) {
2019 return;
2020 }
2021 for (SimpleDUIterator i(mem); i.has_next(); i.next()) {
2022 Node* use = i.get();
2023 if (use->is_MergeMem()) {
2024 wl.push(use);
2025 }
2026 }
2027 }
2028
2029 // Replace the call with the current state of the kit.
2030 void GraphKit::replace_call(CallNode* call, Node* result, bool do_replaced_nodes, bool do_asserts) {
2031 JVMState* ejvms = nullptr;
2032 if (has_exceptions()) {
2033 ejvms = transfer_exceptions_into_jvms();
2034 }
2035
2036 ReplacedNodes replaced_nodes = map()->replaced_nodes();
2037 ReplacedNodes replaced_nodes_exception;
2038 Node* ex_ctl = top();
2039
2040 SafePointNode* final_state = stop();
2041
2042 // Find all the needed outputs of this call
2043 CallProjections callprojs;
2044 call->extract_projections(&callprojs, true, do_asserts);
2045
2046 Unique_Node_List wl;
2047 Node* init_mem = call->in(TypeFunc::Memory);
2048 Node* final_mem = final_state->in(TypeFunc::Memory);
2049 Node* final_ctl = final_state->in(TypeFunc::Control);
2050 Node* final_io = final_state->in(TypeFunc::I_O);
2051
2052 // Replace all the old call edges with the edges from the inlining result
2053 if (callprojs.fallthrough_catchproj != nullptr) {
2054 C->gvn_replace_by(callprojs.fallthrough_catchproj, final_ctl);
2055 }
2056 if (callprojs.fallthrough_memproj != nullptr) {
2057 if (final_mem->is_MergeMem()) {
2058 // Parser's exits MergeMem was not transformed but may be optimized
2059 final_mem = _gvn.transform(final_mem);
2060 }
2061 C->gvn_replace_by(callprojs.fallthrough_memproj, final_mem);
2062 add_mergemem_users_to_worklist(wl, final_mem);
2063 }
2064 if (callprojs.fallthrough_ioproj != nullptr) {
2065 C->gvn_replace_by(callprojs.fallthrough_ioproj, final_io);
2066 }
2067
2068 // Replace the result with the new result if it exists and is used
2069 if (callprojs.resproj != nullptr && result != nullptr) {
2070 C->gvn_replace_by(callprojs.resproj, result);
2071 }
2072
2073 if (ejvms == nullptr) {
2074 // No exception edges to simply kill off those paths
2075 if (callprojs.catchall_catchproj != nullptr) {
2076 C->gvn_replace_by(callprojs.catchall_catchproj, C->top());
2077 }
2078 if (callprojs.catchall_memproj != nullptr) {
2079 C->gvn_replace_by(callprojs.catchall_memproj, C->top());
2080 }
2081 if (callprojs.catchall_ioproj != nullptr) {
2082 C->gvn_replace_by(callprojs.catchall_ioproj, C->top());
2083 }
2084 // Replace the old exception object with top
2085 if (callprojs.exobj != nullptr) {
2086 C->gvn_replace_by(callprojs.exobj, C->top());
2087 }
2088 } else {
2089 GraphKit ekit(ejvms);
2090
2091 // Load my combined exception state into the kit, with all phis transformed:
2092 SafePointNode* ex_map = ekit.combine_and_pop_all_exception_states();
2093 replaced_nodes_exception = ex_map->replaced_nodes();
2094
2095 Node* ex_oop = ekit.use_exception_state(ex_map);
2096
2097 if (callprojs.catchall_catchproj != nullptr) {
2098 C->gvn_replace_by(callprojs.catchall_catchproj, ekit.control());
2099 ex_ctl = ekit.control();
2100 }
2101 if (callprojs.catchall_memproj != nullptr) {
2102 Node* ex_mem = ekit.reset_memory();
2103 C->gvn_replace_by(callprojs.catchall_memproj, ex_mem);
2104 add_mergemem_users_to_worklist(wl, ex_mem);
2105 }
2106 if (callprojs.catchall_ioproj != nullptr) {
2107 C->gvn_replace_by(callprojs.catchall_ioproj, ekit.i_o());
2108 }
2109
2110 // Replace the old exception object with the newly created one
2111 if (callprojs.exobj != nullptr) {
2112 C->gvn_replace_by(callprojs.exobj, ex_oop);
2113 }
2114 }
2115
2116 // Disconnect the call from the graph
2117 call->disconnect_inputs(C);
2118 C->gvn_replace_by(call, C->top());
2119
2120 // Clean up any MergeMems that feed other MergeMems since the
2121 // optimizer doesn't like that.
2122 while (wl.size() > 0) {
2123 _gvn.transform(wl.pop());
2124 }
2125
2126 if (callprojs.fallthrough_catchproj != nullptr && !final_ctl->is_top() && do_replaced_nodes) {
2127 replaced_nodes.apply(C, final_ctl);
2128 }
2129 if (!ex_ctl->is_top() && do_replaced_nodes) {
2130 replaced_nodes_exception.apply(C, ex_ctl);
2131 }
2132 }
2133
2134
2135 //------------------------------increment_counter------------------------------
2136 // for statistics: increment a VM counter by 1
2137
2138 void GraphKit::increment_counter(address counter_addr) {
2139 Node* adr1 = makecon(TypeRawPtr::make(counter_addr));
2140 increment_counter(adr1);
2141 }
2142
2143 void GraphKit::increment_counter(Node* counter_addr) {
2144 Node* ctrl = control();
2145 Node* cnt = make_load(ctrl, counter_addr, TypeLong::LONG, T_LONG, MemNode::unordered);
2146 Node* incr = _gvn.transform(new AddLNode(cnt, _gvn.longcon(1)));
2147 store_to_memory(ctrl, counter_addr, incr, T_LONG, MemNode::unordered);
2148 }
2149
2150 void GraphKit::halt(Node* ctrl, Node* frameptr, const char* reason, bool generate_code_in_product) {
2151 Node* halt = new HaltNode(ctrl, frameptr, reason
2152 PRODUCT_ONLY(COMMA generate_code_in_product));
2153 halt = _gvn.transform(halt);
2154 root()->add_req(halt);
2155 }
2156
2157 //------------------------------uncommon_trap----------------------------------
2158 // Bail out to the interpreter in mid-method. Implemented by calling the
2159 // uncommon_trap blob. This helper function inserts a runtime call with the
2160 // right debug info.
2161 Node* GraphKit::uncommon_trap(int trap_request,
2162 ciKlass* klass, const char* comment,
2163 bool must_throw,
2164 bool keep_exact_action) {
2165 if (failing_internal()) {
2166 stop();
2167 }
2168 if (stopped()) return nullptr; // trap reachable?
2169
2170 // Note: If ProfileTraps is true, and if a deopt. actually
2171 // occurs here, the runtime will make sure an MDO exists. There is
2172 // no need to call method()->ensure_method_data() at this point.
2173
2174 // Set the stack pointer to the right value for reexecution:
2175 set_sp(reexecute_sp());
2176
2177 #ifdef ASSERT
2178 if (!must_throw) {
2179 // Make sure the stack has at least enough depth to execute
2180 // the current bytecode.
2181 int inputs, ignored_depth;
2182 if (compute_stack_effects(inputs, ignored_depth)) {
2183 assert(sp() >= inputs, "must have enough JVMS stack to execute %s: sp=%d, inputs=%d",
2184 Bytecodes::name(java_bc()), sp(), inputs);
2185 }
2186 }
2187 #endif
2188
2189 Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
2190 Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
2191
2192 switch (action) {
2193 case Deoptimization::Action_maybe_recompile:
2194 case Deoptimization::Action_reinterpret:
2195 // Temporary fix for 6529811 to allow virtual calls to be sure they
2196 // get the chance to go from mono->bi->mega
2197 if (!keep_exact_action &&
2198 Deoptimization::trap_request_index(trap_request) < 0 &&
2199 too_many_recompiles(reason)) {
2200 // This BCI is causing too many recompilations.
2201 if (C->log() != nullptr) {
2202 C->log()->elem("observe that='trap_action_change' reason='%s' from='%s' to='none'",
2203 Deoptimization::trap_reason_name(reason),
2204 Deoptimization::trap_action_name(action));
2205 }
2206 action = Deoptimization::Action_none;
2207 trap_request = Deoptimization::make_trap_request(reason, action);
2208 } else {
2209 C->set_trap_can_recompile(true);
2210 }
2211 break;
2212 case Deoptimization::Action_make_not_entrant:
2213 C->set_trap_can_recompile(true);
2214 break;
2215 case Deoptimization::Action_none:
2216 case Deoptimization::Action_make_not_compilable:
2217 break;
2218 default:
2219 #ifdef ASSERT
2220 fatal("unknown action %d: %s", action, Deoptimization::trap_action_name(action));
2221 #endif
2222 break;
2223 }
2224
2225 if (TraceOptoParse) {
2226 char buf[100];
2227 tty->print_cr("Uncommon trap %s at bci:%d",
2228 Deoptimization::format_trap_request(buf, sizeof(buf),
2229 trap_request), bci());
2230 }
2231
2232 CompileLog* log = C->log();
2233 if (log != nullptr) {
2234 int kid = (klass == nullptr)? -1: log->identify(klass);
2235 log->begin_elem("uncommon_trap bci='%d'", bci());
2236 char buf[100];
2237 log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf),
2238 trap_request));
2239 if (kid >= 0) log->print(" klass='%d'", kid);
2240 if (comment != nullptr) log->print(" comment='%s'", comment);
2241 log->end_elem();
2242 }
2243
2244 // Make sure any guarding test views this path as very unlikely
2245 Node *i0 = control()->in(0);
2246 if (i0 != nullptr && i0->is_If()) { // Found a guarding if test?
2247 IfNode *iff = i0->as_If();
2248 float f = iff->_prob; // Get prob
2249 if (control()->Opcode() == Op_IfTrue) {
2250 if (f > PROB_UNLIKELY_MAG(4))
2251 iff->_prob = PROB_MIN;
2252 } else {
2253 if (f < PROB_LIKELY_MAG(4))
2254 iff->_prob = PROB_MAX;
2255 }
2256 }
2257
2258 // Clear out dead values from the debug info.
2259 kill_dead_locals();
2260
2261 // Now insert the uncommon trap subroutine call
2262 address call_addr = OptoRuntime::uncommon_trap_blob()->entry_point();
2263 const TypePtr* no_memory_effects = nullptr;
2264 // Pass the index of the class to be loaded
2265 Node* call = make_runtime_call(RC_NO_LEAF | RC_UNCOMMON |
2266 (must_throw ? RC_MUST_THROW : 0),
2267 OptoRuntime::uncommon_trap_Type(),
2268 call_addr, "uncommon_trap", no_memory_effects,
2269 intcon(trap_request));
2270 assert(call->as_CallStaticJava()->uncommon_trap_request() == trap_request,
2271 "must extract request correctly from the graph");
2272 assert(trap_request != 0, "zero value reserved by uncommon_trap_request");
2273
2274 call->set_req(TypeFunc::ReturnAdr, returnadr());
2275 // The debug info is the only real input to this call.
2276
2277 // Halt-and-catch fire here. The above call should never return!
2278 // We only emit code for the HaltNode in debug, which is enough for
2279 // verifying correctness. In product, we don't want to emit it so
2280 // that we can save on code space. HaltNode often get folded because
2281 // the compiler can prove that the unreachable path is dead. But we
2282 // cannot generally expect that for uncommon traps, which are often
2283 // reachable and occasionally taken.
2284 halt(control(), frameptr(),
2285 "uncommon trap returned which should never happen",
2286 false /* don't emit code in product */);
2287 stop_and_kill_map();
2288 return call;
2289 }
2290
2291
2292 //--------------------------just_allocated_object------------------------------
2293 // Report the object that was just allocated.
2294 // It must be the case that there are no intervening safepoints.
2295 // We use this to determine if an object is so "fresh" that
2296 // it does not require card marks.
2297 Node* GraphKit::just_allocated_object(Node* current_control) {
2298 Node* ctrl = current_control;
2299 // Object::<init> is invoked after allocation, most of invoke nodes
2300 // will be reduced, but a region node is kept in parse time, we check
2301 // the pattern and skip the region node if it degraded to a copy.
2302 if (ctrl != nullptr && ctrl->is_Region() && ctrl->req() == 2 &&
2303 ctrl->as_Region()->is_copy()) {
2304 ctrl = ctrl->as_Region()->is_copy();
2305 }
2306 if (C->recent_alloc_ctl() == ctrl) {
2307 return C->recent_alloc_obj();
2308 }
2309 return nullptr;
2310 }
2311
2312
2313 /**
2314 * Record profiling data exact_kls for Node n with the type system so
2315 * that it can propagate it (speculation)
2316 *
2317 * @param n node that the type applies to
2318 * @param exact_kls type from profiling
2319 * @param maybe_null did profiling see null?
2320 *
2321 * @return node with improved type
2322 */
2323 Node* GraphKit::record_profile_for_speculation(Node* n, ciKlass* exact_kls, ProfilePtrKind ptr_kind) {
2324 const Type* current_type = _gvn.type(n);
2325 assert(UseTypeSpeculation, "type speculation must be on");
2326
2327 const TypePtr* speculative = current_type->speculative();
2328
2329 // Should the klass from the profile be recorded in the speculative type?
2330 if (current_type->would_improve_type(exact_kls, jvms()->depth())) {
2331 const TypeKlassPtr* tklass = TypeKlassPtr::make(exact_kls, Type::trust_interfaces);
2332 const TypeOopPtr* xtype = tklass->as_instance_type();
2333 assert(xtype->klass_is_exact(), "Should be exact");
2334 // Any reason to believe n is not null (from this profiling or a previous one)?
2335 assert(ptr_kind != ProfileAlwaysNull, "impossible here");
2336 const TypePtr* ptr = (ptr_kind == ProfileMaybeNull && current_type->speculative_maybe_null()) ? TypePtr::BOTTOM : TypePtr::NOTNULL;
2337 // record the new speculative type's depth
2338 speculative = xtype->cast_to_ptr_type(ptr->ptr())->is_ptr();
2339 speculative = speculative->with_inline_depth(jvms()->depth());
2340 } else if (current_type->would_improve_ptr(ptr_kind)) {
2341 // Profiling report that null was never seen so we can change the
2342 // speculative type to non null ptr.
2343 if (ptr_kind == ProfileAlwaysNull) {
2344 speculative = TypePtr::NULL_PTR;
2345 } else {
2346 assert(ptr_kind == ProfileNeverNull, "nothing else is an improvement");
2347 const TypePtr* ptr = TypePtr::NOTNULL;
2348 if (speculative != nullptr) {
2349 speculative = speculative->cast_to_ptr_type(ptr->ptr())->is_ptr();
2350 } else {
2351 speculative = ptr;
2352 }
2353 }
2354 }
2355
2356 if (speculative != current_type->speculative()) {
2357 // Build a type with a speculative type (what we think we know
2358 // about the type but will need a guard when we use it)
2359 const TypeOopPtr* spec_type = TypeOopPtr::make(TypePtr::BotPTR, Type::OffsetBot, TypeOopPtr::InstanceBot, speculative);
2360 // We're changing the type, we need a new CheckCast node to carry
2361 // the new type. The new type depends on the control: what
2362 // profiling tells us is only valid from here as far as we can
2363 // tell.
2364 Node* cast = new CheckCastPPNode(control(), n, current_type->remove_speculative()->join_speculative(spec_type));
2365 cast = _gvn.transform(cast);
2366 replace_in_map(n, cast);
2367 n = cast;
2368 }
2369
2370 return n;
2371 }
2372
2373 /**
2374 * Record profiling data from receiver profiling at an invoke with the
2375 * type system so that it can propagate it (speculation)
2376 *
2377 * @param n receiver node
2378 *
2379 * @return node with improved type
2380 */
2381 Node* GraphKit::record_profiled_receiver_for_speculation(Node* n) {
2382 if (!UseTypeSpeculation) {
2383 return n;
2384 }
2385 ciKlass* exact_kls = profile_has_unique_klass();
2386 ProfilePtrKind ptr_kind = ProfileMaybeNull;
2387 if ((java_bc() == Bytecodes::_checkcast ||
2388 java_bc() == Bytecodes::_instanceof ||
2389 java_bc() == Bytecodes::_aastore) &&
2390 method()->method_data()->is_mature()) {
2391 ciProfileData* data = method()->method_data()->bci_to_data(bci());
2392 if (data != nullptr) {
2393 if (!data->as_BitData()->null_seen()) {
2394 ptr_kind = ProfileNeverNull;
2395 } else {
2396 if (TypeProfileCasts) {
2397 assert(data->is_ReceiverTypeData(), "bad profile data type");
2398 ciReceiverTypeData* call = (ciReceiverTypeData*)data->as_ReceiverTypeData();
2399 uint i = 0;
2400 for (; i < call->row_limit(); i++) {
2401 ciKlass* receiver = call->receiver(i);
2402 if (receiver != nullptr) {
2403 break;
2404 }
2405 }
2406 ptr_kind = (i == call->row_limit()) ? ProfileAlwaysNull : ProfileMaybeNull;
2407 }
2408 }
2409 }
2410 }
2411 return record_profile_for_speculation(n, exact_kls, ptr_kind);
2412 }
2413
2414 /**
2415 * Record profiling data from argument profiling at an invoke with the
2416 * type system so that it can propagate it (speculation)
2417 *
2418 * @param dest_method target method for the call
2419 * @param bc what invoke bytecode is this?
2420 */
2421 void GraphKit::record_profiled_arguments_for_speculation(ciMethod* dest_method, Bytecodes::Code bc) {
2422 if (!UseTypeSpeculation) {
2423 return;
2424 }
2425 const TypeFunc* tf = TypeFunc::make(dest_method);
2426 int nargs = tf->domain()->cnt() - TypeFunc::Parms;
2427 int skip = Bytecodes::has_receiver(bc) ? 1 : 0;
2428 for (int j = skip, i = 0; j < nargs && i < TypeProfileArgsLimit; j++) {
2429 const Type *targ = tf->domain()->field_at(j + TypeFunc::Parms);
2430 if (is_reference_type(targ->basic_type())) {
2431 ProfilePtrKind ptr_kind = ProfileMaybeNull;
2432 ciKlass* better_type = nullptr;
2433 if (method()->argument_profiled_type(bci(), i, better_type, ptr_kind)) {
2434 record_profile_for_speculation(argument(j), better_type, ptr_kind);
2435 }
2436 i++;
2437 }
2438 }
2439 }
2440
2441 /**
2442 * Record profiling data from parameter profiling at an invoke with
2443 * the type system so that it can propagate it (speculation)
2444 */
2445 void GraphKit::record_profiled_parameters_for_speculation() {
2446 if (!UseTypeSpeculation) {
2447 return;
2448 }
2449 for (int i = 0, j = 0; i < method()->arg_size() ; i++) {
2450 if (_gvn.type(local(i))->isa_oopptr()) {
2451 ProfilePtrKind ptr_kind = ProfileMaybeNull;
2452 ciKlass* better_type = nullptr;
2453 if (method()->parameter_profiled_type(j, better_type, ptr_kind)) {
2454 record_profile_for_speculation(local(i), better_type, ptr_kind);
2455 }
2456 j++;
2457 }
2458 }
2459 }
2460
2461 /**
2462 * Record profiling data from return value profiling at an invoke with
2463 * the type system so that it can propagate it (speculation)
2464 */
2465 void GraphKit::record_profiled_return_for_speculation() {
2466 if (!UseTypeSpeculation) {
2467 return;
2468 }
2469 ProfilePtrKind ptr_kind = ProfileMaybeNull;
2470 ciKlass* better_type = nullptr;
2471 if (method()->return_profiled_type(bci(), better_type, ptr_kind)) {
2472 // If profiling reports a single type for the return value,
2473 // feed it to the type system so it can propagate it as a
2474 // speculative type
2475 record_profile_for_speculation(stack(sp()-1), better_type, ptr_kind);
2476 }
2477 }
2478
2479
2480 //=============================================================================
2481 // Generate a fast path/slow path idiom. Graph looks like:
2482 // [foo] indicates that 'foo' is a parameter
2483 //
2484 // [in] null
2485 // \ /
2486 // CmpP
2487 // Bool ne
2488 // If
2489 // / \
2490 // True False-<2>
2491 // / |
2492 // / cast_not_null
2493 // Load | | ^
2494 // [fast_test] | |
2495 // gvn to opt_test | |
2496 // / \ | <1>
2497 // True False |
2498 // | \\ |
2499 // [slow_call] \[fast_result]
2500 // Ctl Val \ \
2501 // | \ \
2502 // Catch <1> \ \
2503 // / \ ^ \ \
2504 // Ex No_Ex | \ \
2505 // | \ \ | \ <2> \
2506 // ... \ [slow_res] | | \ [null_result]
2507 // \ \--+--+--- | |
2508 // \ | / \ | /
2509 // --------Region Phi
2510 //
2511 //=============================================================================
2512 // Code is structured as a series of driver functions all called 'do_XXX' that
2513 // call a set of helper functions. Helper functions first, then drivers.
2514
2515 //------------------------------null_check_oop---------------------------------
2516 // Null check oop. Set null-path control into Region in slot 3.
2517 // Make a cast-not-nullness use the other not-null control. Return cast.
2518 Node* GraphKit::null_check_oop(Node* value, Node* *null_control,
2519 bool never_see_null,
2520 bool safe_for_replace,
2521 bool speculative) {
2522 // Initial null check taken path
2523 (*null_control) = top();
2524 Node* cast = null_check_common(value, T_OBJECT, false, null_control, speculative);
2525
2526 // Generate uncommon_trap:
2527 if (never_see_null && (*null_control) != top()) {
2528 // If we see an unexpected null at a check-cast we record it and force a
2529 // recompile; the offending check-cast will be compiled to handle nulls.
2530 // If we see more than one offending BCI, then all checkcasts in the
2531 // method will be compiled to handle nulls.
2532 PreserveJVMState pjvms(this);
2533 set_control(*null_control);
2534 replace_in_map(value, null());
2535 Deoptimization::DeoptReason reason = Deoptimization::reason_null_check(speculative);
2536 uncommon_trap(reason,
2537 Deoptimization::Action_make_not_entrant);
2538 (*null_control) = top(); // null path is dead
2539 }
2540 if ((*null_control) == top() && safe_for_replace) {
2541 replace_in_map(value, cast);
2542 }
2543
2544 // Cast away null-ness on the result
2545 return cast;
2546 }
2547
2548 //------------------------------opt_iff----------------------------------------
2549 // Optimize the fast-check IfNode. Set the fast-path region slot 2.
2550 // Return slow-path control.
2551 Node* GraphKit::opt_iff(Node* region, Node* iff) {
2552 IfNode *opt_iff = _gvn.transform(iff)->as_If();
2553
2554 // Fast path taken; set region slot 2
2555 Node *fast_taken = _gvn.transform( new IfFalseNode(opt_iff) );
2556 region->init_req(2,fast_taken); // Capture fast-control
2557
2558 // Fast path not-taken, i.e. slow path
2559 Node *slow_taken = _gvn.transform( new IfTrueNode(opt_iff) );
2560 return slow_taken;
2561 }
2562
2563 //-----------------------------make_runtime_call-------------------------------
2564 Node* GraphKit::make_runtime_call(int flags,
2565 const TypeFunc* call_type, address call_addr,
2566 const char* call_name,
2567 const TypePtr* adr_type,
2568 // The following parms are all optional.
2569 // The first null ends the list.
2570 Node* parm0, Node* parm1,
2571 Node* parm2, Node* parm3,
2572 Node* parm4, Node* parm5,
2573 Node* parm6, Node* parm7) {
2574 assert(call_addr != nullptr, "must not call null targets");
2575
2576 // Slow-path call
2577 bool is_leaf = !(flags & RC_NO_LEAF);
2578 bool has_io = (!is_leaf && !(flags & RC_NO_IO));
2579 if (call_name == nullptr) {
2580 assert(!is_leaf, "must supply name for leaf");
2581 call_name = OptoRuntime::stub_name(call_addr);
2582 }
2583 CallNode* call;
2584 if (!is_leaf) {
2585 call = new CallStaticJavaNode(call_type, call_addr, call_name, adr_type);
2586 } else if (flags & RC_NO_FP) {
2587 call = new CallLeafNoFPNode(call_type, call_addr, call_name, adr_type);
2588 } else if (flags & RC_VECTOR){
2589 uint num_bits = call_type->range()->field_at(TypeFunc::Parms)->is_vect()->length_in_bytes() * BitsPerByte;
2590 call = new CallLeafVectorNode(call_type, call_addr, call_name, adr_type, num_bits);
2591 } else if (flags & RC_PURE) {
2592 assert(adr_type == nullptr, "pure call does not touch memory");
2593 call = new CallLeafPureNode(call_type, call_addr, call_name);
2594 } else {
2595 call = new CallLeafNode(call_type, call_addr, call_name, adr_type);
2596 }
2597
2598 // The following is similar to set_edges_for_java_call,
2599 // except that the memory effects of the call are restricted to AliasIdxRaw.
2600
2601 // Slow path call has no side-effects, uses few values
2602 bool wide_in = !(flags & RC_NARROW_MEM);
2603 bool wide_out = (C->get_alias_index(adr_type) == Compile::AliasIdxBot);
2604
2605 Node* prev_mem = nullptr;
2606 if (wide_in) {
2607 prev_mem = set_predefined_input_for_runtime_call(call);
2608 } else {
2609 assert(!wide_out, "narrow in => narrow out");
2610 Node* narrow_mem = memory(adr_type);
2611 prev_mem = set_predefined_input_for_runtime_call(call, narrow_mem);
2612 }
2613
2614 // Hook each parm in order. Stop looking at the first null.
2615 if (parm0 != nullptr) { call->init_req(TypeFunc::Parms+0, parm0);
2616 if (parm1 != nullptr) { call->init_req(TypeFunc::Parms+1, parm1);
2617 if (parm2 != nullptr) { call->init_req(TypeFunc::Parms+2, parm2);
2618 if (parm3 != nullptr) { call->init_req(TypeFunc::Parms+3, parm3);
2619 if (parm4 != nullptr) { call->init_req(TypeFunc::Parms+4, parm4);
2620 if (parm5 != nullptr) { call->init_req(TypeFunc::Parms+5, parm5);
2621 if (parm6 != nullptr) { call->init_req(TypeFunc::Parms+6, parm6);
2622 if (parm7 != nullptr) { call->init_req(TypeFunc::Parms+7, parm7);
2623 /* close each nested if ===> */ } } } } } } } }
2624 assert(call->in(call->req()-1) != nullptr, "must initialize all parms");
2625
2626 if (!is_leaf) {
2627 // Non-leaves can block and take safepoints:
2628 add_safepoint_edges(call, ((flags & RC_MUST_THROW) != 0));
2629 }
2630 // Non-leaves can throw exceptions:
2631 if (has_io) {
2632 call->set_req(TypeFunc::I_O, i_o());
2633 }
2634
2635 if (flags & RC_UNCOMMON) {
2636 // Set the count to a tiny probability. Cf. Estimate_Block_Frequency.
2637 // (An "if" probability corresponds roughly to an unconditional count.
2638 // Sort of.)
2639 call->set_cnt(PROB_UNLIKELY_MAG(4));
2640 }
2641
2642 Node* c = _gvn.transform(call);
2643 assert(c == call, "cannot disappear");
2644
2645 if (wide_out) {
2646 // Slow path call has full side-effects.
2647 set_predefined_output_for_runtime_call(call);
2648 } else {
2649 // Slow path call has few side-effects, and/or sets few values.
2650 set_predefined_output_for_runtime_call(call, prev_mem, adr_type);
2651 }
2652
2653 if (has_io) {
2654 set_i_o(_gvn.transform(new ProjNode(call, TypeFunc::I_O)));
2655 }
2656 return call;
2657
2658 }
2659
2660 // i2b
2661 Node* GraphKit::sign_extend_byte(Node* in) {
2662 Node* tmp = _gvn.transform(new LShiftINode(in, _gvn.intcon(24)));
2663 return _gvn.transform(new RShiftINode(tmp, _gvn.intcon(24)));
2664 }
2665
2666 // i2s
2667 Node* GraphKit::sign_extend_short(Node* in) {
2668 Node* tmp = _gvn.transform(new LShiftINode(in, _gvn.intcon(16)));
2669 return _gvn.transform(new RShiftINode(tmp, _gvn.intcon(16)));
2670 }
2671
2672 //------------------------------merge_memory-----------------------------------
2673 // Merge memory from one path into the current memory state.
2674 void GraphKit::merge_memory(Node* new_mem, Node* region, int new_path) {
2675 for (MergeMemStream mms(merged_memory(), new_mem->as_MergeMem()); mms.next_non_empty2(); ) {
2676 Node* old_slice = mms.force_memory();
2677 Node* new_slice = mms.memory2();
2678 if (old_slice != new_slice) {
2679 PhiNode* phi;
2680 if (old_slice->is_Phi() && old_slice->as_Phi()->region() == region) {
2681 if (mms.is_empty()) {
2682 // clone base memory Phi's inputs for this memory slice
2683 assert(old_slice == mms.base_memory(), "sanity");
2684 phi = PhiNode::make(region, nullptr, Type::MEMORY, mms.adr_type(C));
2685 _gvn.set_type(phi, Type::MEMORY);
2686 for (uint i = 1; i < phi->req(); i++) {
2687 phi->init_req(i, old_slice->in(i));
2688 }
2689 } else {
2690 phi = old_slice->as_Phi(); // Phi was generated already
2691 }
2692 } else {
2693 phi = PhiNode::make(region, old_slice, Type::MEMORY, mms.adr_type(C));
2694 _gvn.set_type(phi, Type::MEMORY);
2695 }
2696 phi->set_req(new_path, new_slice);
2697 mms.set_memory(phi);
2698 }
2699 }
2700 }
2701
2702 //------------------------------make_slow_call_ex------------------------------
2703 // Make the exception handler hookups for the slow call
2704 void GraphKit::make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj, bool deoptimize) {
2705 if (stopped()) return;
2706
2707 // Make a catch node with just two handlers: fall-through and catch-all
2708 Node* i_o = _gvn.transform( new ProjNode(call, TypeFunc::I_O, separate_io_proj) );
2709 Node* catc = _gvn.transform( new CatchNode(control(), i_o, 2) );
2710 Node* norm = new CatchProjNode(catc, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci);
2711 _gvn.set_type_bottom(norm);
2712 C->record_for_igvn(norm);
2713 Node* excp = _gvn.transform( new CatchProjNode(catc, CatchProjNode::catch_all_index, CatchProjNode::no_handler_bci) );
2714
2715 { PreserveJVMState pjvms(this);
2716 set_control(excp);
2717 set_i_o(i_o);
2718
2719 if (excp != top()) {
2720 if (deoptimize) {
2721 // Deoptimize if an exception is caught. Don't construct exception state in this case.
2722 uncommon_trap(Deoptimization::Reason_unhandled,
2723 Deoptimization::Action_none);
2724 } else {
2725 // Create an exception state also.
2726 // Use an exact type if the caller has a specific exception.
2727 const Type* ex_type = TypeOopPtr::make_from_klass_unique(ex_klass)->cast_to_ptr_type(TypePtr::NotNull);
2728 Node* ex_oop = new CreateExNode(ex_type, control(), i_o);
2729 add_exception_state(make_exception_state(_gvn.transform(ex_oop)));
2730 }
2731 }
2732 }
2733
2734 // Get the no-exception control from the CatchNode.
2735 set_control(norm);
2736 }
2737
2738 static IfNode* gen_subtype_check_compare(Node* ctrl, Node* in1, Node* in2, BoolTest::mask test, float p, PhaseGVN& gvn, BasicType bt) {
2739 Node* cmp = nullptr;
2740 switch(bt) {
2741 case T_INT: cmp = new CmpINode(in1, in2); break;
2742 case T_ADDRESS: cmp = new CmpPNode(in1, in2); break;
2743 default: fatal("unexpected comparison type %s", type2name(bt));
2744 }
2745 cmp = gvn.transform(cmp);
2746 Node* bol = gvn.transform(new BoolNode(cmp, test));
2747 IfNode* iff = new IfNode(ctrl, bol, p, COUNT_UNKNOWN);
2748 gvn.transform(iff);
2749 if (!bol->is_Con()) gvn.record_for_igvn(iff);
2750 return iff;
2751 }
2752
2753 //-------------------------------gen_subtype_check-----------------------------
2754 // Generate a subtyping check. Takes as input the subtype and supertype.
2755 // Returns 2 values: sets the default control() to the true path and returns
2756 // the false path. Only reads invariant memory; sets no (visible) memory.
2757 // The PartialSubtypeCheckNode sets the hidden 1-word cache in the encoding
2758 // but that's not exposed to the optimizer. This call also doesn't take in an
2759 // Object; if you wish to check an Object you need to load the Object's class
2760 // prior to coming here.
2761 Node* Phase::gen_subtype_check(Node* subklass, Node* superklass, Node** ctrl, Node* mem, PhaseGVN& gvn,
2762 ciMethod* method, int bci) {
2763 Compile* C = gvn.C;
2764 if ((*ctrl)->is_top()) {
2765 return C->top();
2766 }
2767
2768 // Fast check for identical types, perhaps identical constants.
2769 // The types can even be identical non-constants, in cases
2770 // involving Array.newInstance, Object.clone, etc.
2771 if (subklass == superklass)
2772 return C->top(); // false path is dead; no test needed.
2773
2774 if (gvn.type(superklass)->singleton()) {
2775 const TypeKlassPtr* superk = gvn.type(superklass)->is_klassptr();
2776 const TypeKlassPtr* subk = gvn.type(subklass)->is_klassptr();
2777
2778 // In the common case of an exact superklass, try to fold up the
2779 // test before generating code. You may ask, why not just generate
2780 // the code and then let it fold up? The answer is that the generated
2781 // code will necessarily include null checks, which do not always
2782 // completely fold away. If they are also needless, then they turn
2783 // into a performance loss. Example:
2784 // Foo[] fa = blah(); Foo x = fa[0]; fa[1] = x;
2785 // Here, the type of 'fa' is often exact, so the store check
2786 // of fa[1]=x will fold up, without testing the nullness of x.
2787 //
2788 // At macro expansion, we would have already folded the SubTypeCheckNode
2789 // being expanded here because we always perform the static sub type
2790 // check in SubTypeCheckNode::sub() regardless of whether
2791 // StressReflectiveCode is set or not. We can therefore skip this
2792 // static check when StressReflectiveCode is on.
2793 switch (C->static_subtype_check(superk, subk)) {
2794 case Compile::SSC_always_false:
2795 {
2796 Node* always_fail = *ctrl;
2797 *ctrl = gvn.C->top();
2798 return always_fail;
2799 }
2800 case Compile::SSC_always_true:
2801 return C->top();
2802 case Compile::SSC_easy_test:
2803 {
2804 // Just do a direct pointer compare and be done.
2805 IfNode* iff = gen_subtype_check_compare(*ctrl, subklass, superklass, BoolTest::eq, PROB_STATIC_FREQUENT, gvn, T_ADDRESS);
2806 *ctrl = gvn.transform(new IfTrueNode(iff));
2807 return gvn.transform(new IfFalseNode(iff));
2808 }
2809 case Compile::SSC_full_test:
2810 break;
2811 default:
2812 ShouldNotReachHere();
2813 }
2814 }
2815
2816 // %%% Possible further optimization: Even if the superklass is not exact,
2817 // if the subklass is the unique subtype of the superklass, the check
2818 // will always succeed. We could leave a dependency behind to ensure this.
2819
2820 // First load the super-klass's check-offset
2821 Node* p1 = gvn.transform(AddPNode::make_off_heap(superklass, gvn.MakeConX(in_bytes(Klass::super_check_offset_offset()))));
2822 Node* m = C->immutable_memory();
2823 Node* chk_off = gvn.transform(new LoadINode(nullptr, m, p1, gvn.type(p1)->is_ptr(), TypeInt::INT, MemNode::unordered));
2824 int cacheoff_con = in_bytes(Klass::secondary_super_cache_offset());
2825 const TypeInt* chk_off_t = chk_off->Value(&gvn)->isa_int();
2826 int chk_off_con = (chk_off_t != nullptr && chk_off_t->is_con()) ? chk_off_t->get_con() : cacheoff_con;
2827 bool might_be_cache = (chk_off_con == cacheoff_con);
2828
2829 // Load from the sub-klass's super-class display list, or a 1-word cache of
2830 // the secondary superclass list, or a failing value with a sentinel offset
2831 // if the super-klass is an interface or exceptionally deep in the Java
2832 // hierarchy and we have to scan the secondary superclass list the hard way.
2833 // Worst-case type is a little odd: null is allowed as a result (usually
2834 // klass loads can never produce a null).
2835 Node *chk_off_X = chk_off;
2836 #ifdef _LP64
2837 chk_off_X = gvn.transform(new ConvI2LNode(chk_off_X));
2838 #endif
2839 Node* p2 = gvn.transform(AddPNode::make_off_heap(subklass, chk_off_X));
2840 // For some types like interfaces the following loadKlass is from a 1-word
2841 // cache which is mutable so can't use immutable memory. Other
2842 // types load from the super-class display table which is immutable.
2843 Node* kmem = C->immutable_memory();
2844 // secondary_super_cache is not immutable but can be treated as such because:
2845 // - no ideal node writes to it in a way that could cause an
2846 // incorrect/missed optimization of the following Load.
2847 // - it's a cache so, worse case, not reading the latest value
2848 // wouldn't cause incorrect execution
2849 if (might_be_cache && mem != nullptr) {
2850 kmem = mem->is_MergeMem() ? mem->as_MergeMem()->memory_at(C->get_alias_index(gvn.type(p2)->is_ptr())) : mem;
2851 }
2852 Node* nkls = gvn.transform(LoadKlassNode::make(gvn, kmem, p2, gvn.type(p2)->is_ptr(), TypeInstKlassPtr::OBJECT_OR_NULL));
2853
2854 // Compile speed common case: ARE a subtype and we canNOT fail
2855 if (superklass == nkls) {
2856 return C->top(); // false path is dead; no test needed.
2857 }
2858
2859 // Gather the various success & failures here
2860 RegionNode* r_not_subtype = new RegionNode(3);
2861 gvn.record_for_igvn(r_not_subtype);
2862 RegionNode* r_ok_subtype = new RegionNode(4);
2863 gvn.record_for_igvn(r_ok_subtype);
2864
2865 // If we might perform an expensive check, first try to take advantage of profile data that was attached to the
2866 // SubTypeCheck node
2867 if (might_be_cache && method != nullptr && VM_Version::profile_all_receivers_at_type_check()) {
2868 ciCallProfile profile = method->call_profile_at_bci(bci);
2869 float total_prob = 0;
2870 for (int i = 0; profile.has_receiver(i); ++i) {
2871 float prob = profile.receiver_prob(i);
2872 total_prob += prob;
2873 }
2874 if (total_prob * 100. >= TypeProfileSubTypeCheckCommonThreshold) {
2875 const TypeKlassPtr* superk = gvn.type(superklass)->is_klassptr();
2876 for (int i = 0; profile.has_receiver(i); ++i) {
2877 ciKlass* klass = profile.receiver(i);
2878 const TypeKlassPtr* klass_t = TypeKlassPtr::make(klass);
2879 Compile::SubTypeCheckResult result = C->static_subtype_check(superk, klass_t);
2880 if (result != Compile::SSC_always_true && result != Compile::SSC_always_false) {
2881 continue;
2882 }
2883 float prob = profile.receiver_prob(i);
2884 ConNode* klass_node = gvn.makecon(klass_t);
2885 IfNode* iff = gen_subtype_check_compare(*ctrl, subklass, klass_node, BoolTest::eq, prob, gvn, T_ADDRESS);
2886 Node* iftrue = gvn.transform(new IfTrueNode(iff));
2887
2888 if (result == Compile::SSC_always_true) {
2889 r_ok_subtype->add_req(iftrue);
2890 } else {
2891 assert(result == Compile::SSC_always_false, "");
2892 r_not_subtype->add_req(iftrue);
2893 }
2894 *ctrl = gvn.transform(new IfFalseNode(iff));
2895 }
2896 }
2897 }
2898
2899 // See if we get an immediate positive hit. Happens roughly 83% of the
2900 // time. Test to see if the value loaded just previously from the subklass
2901 // is exactly the superklass.
2902 IfNode *iff1 = gen_subtype_check_compare(*ctrl, superklass, nkls, BoolTest::eq, PROB_LIKELY(0.83f), gvn, T_ADDRESS);
2903 Node *iftrue1 = gvn.transform( new IfTrueNode (iff1));
2904 *ctrl = gvn.transform(new IfFalseNode(iff1));
2905
2906 // Compile speed common case: Check for being deterministic right now. If
2907 // chk_off is a constant and not equal to cacheoff then we are NOT a
2908 // subklass. In this case we need exactly the 1 test above and we can
2909 // return those results immediately.
2910 if (!might_be_cache) {
2911 Node* not_subtype_ctrl = *ctrl;
2912 *ctrl = iftrue1; // We need exactly the 1 test above
2913 PhaseIterGVN* igvn = gvn.is_IterGVN();
2914 if (igvn != nullptr) {
2915 igvn->remove_globally_dead_node(r_ok_subtype, PhaseIterGVN::NodeOrigin::Speculative);
2916 igvn->remove_globally_dead_node(r_not_subtype, PhaseIterGVN::NodeOrigin::Speculative);
2917 }
2918 return not_subtype_ctrl;
2919 }
2920
2921 r_ok_subtype->init_req(1, iftrue1);
2922
2923 // Check for immediate negative hit. Happens roughly 11% of the time (which
2924 // is roughly 63% of the remaining cases). Test to see if the loaded
2925 // check-offset points into the subklass display list or the 1-element
2926 // cache. If it points to the display (and NOT the cache) and the display
2927 // missed then it's not a subtype.
2928 Node *cacheoff = gvn.intcon(cacheoff_con);
2929 IfNode *iff2 = gen_subtype_check_compare(*ctrl, chk_off, cacheoff, BoolTest::ne, PROB_LIKELY(0.63f), gvn, T_INT);
2930 r_not_subtype->init_req(1, gvn.transform(new IfTrueNode (iff2)));
2931 *ctrl = gvn.transform(new IfFalseNode(iff2));
2932
2933 // Check for self. Very rare to get here, but it is taken 1/3 the time.
2934 // No performance impact (too rare) but allows sharing of secondary arrays
2935 // which has some footprint reduction.
2936 IfNode *iff3 = gen_subtype_check_compare(*ctrl, subklass, superklass, BoolTest::eq, PROB_LIKELY(0.36f), gvn, T_ADDRESS);
2937 r_ok_subtype->init_req(2, gvn.transform(new IfTrueNode(iff3)));
2938 *ctrl = gvn.transform(new IfFalseNode(iff3));
2939
2940 // -- Roads not taken here: --
2941 // We could also have chosen to perform the self-check at the beginning
2942 // of this code sequence, as the assembler does. This would not pay off
2943 // the same way, since the optimizer, unlike the assembler, can perform
2944 // static type analysis to fold away many successful self-checks.
2945 // Non-foldable self checks work better here in second position, because
2946 // the initial primary superclass check subsumes a self-check for most
2947 // types. An exception would be a secondary type like array-of-interface,
2948 // which does not appear in its own primary supertype display.
2949 // Finally, we could have chosen to move the self-check into the
2950 // PartialSubtypeCheckNode, and from there out-of-line in a platform
2951 // dependent manner. But it is worthwhile to have the check here,
2952 // where it can be perhaps be optimized. The cost in code space is
2953 // small (register compare, branch).
2954
2955 // Now do a linear scan of the secondary super-klass array. Again, no real
2956 // performance impact (too rare) but it's gotta be done.
2957 // Since the code is rarely used, there is no penalty for moving it
2958 // out of line, and it can only improve I-cache density.
2959 // The decision to inline or out-of-line this final check is platform
2960 // dependent, and is found in the AD file definition of PartialSubtypeCheck.
2961 Node* psc = gvn.transform(
2962 new PartialSubtypeCheckNode(*ctrl, subklass, superklass));
2963
2964 IfNode *iff4 = gen_subtype_check_compare(*ctrl, psc, gvn.zerocon(T_OBJECT), BoolTest::ne, PROB_FAIR, gvn, T_ADDRESS);
2965 r_not_subtype->init_req(2, gvn.transform(new IfTrueNode (iff4)));
2966 r_ok_subtype ->init_req(3, gvn.transform(new IfFalseNode(iff4)));
2967
2968 // Return false path; set default control to true path.
2969 *ctrl = gvn.transform(r_ok_subtype);
2970 return gvn.transform(r_not_subtype);
2971 }
2972
2973 Node* GraphKit::gen_subtype_check(Node* obj_or_subklass, Node* superklass) {
2974 bool expand_subtype_check = C->post_loop_opts_phase(); // macro node expansion is over
2975 if (expand_subtype_check) {
2976 MergeMemNode* mem = merged_memory();
2977 Node* ctrl = control();
2978 Node* subklass = obj_or_subklass;
2979 if (!_gvn.type(obj_or_subklass)->isa_klassptr()) {
2980 subklass = load_object_klass(obj_or_subklass);
2981 }
2982
2983 Node* n = Phase::gen_subtype_check(subklass, superklass, &ctrl, mem, _gvn, method(), bci());
2984 set_control(ctrl);
2985 return n;
2986 }
2987
2988 Node* check = _gvn.transform(new SubTypeCheckNode(C, obj_or_subklass, superklass, method(), bci()));
2989 Node* bol = _gvn.transform(new BoolNode(check, BoolTest::eq));
2990 IfNode* iff = create_and_xform_if(control(), bol, PROB_STATIC_FREQUENT, COUNT_UNKNOWN);
2991 set_control(_gvn.transform(new IfTrueNode(iff)));
2992 return _gvn.transform(new IfFalseNode(iff));
2993 }
2994
2995 // Profile-driven exact type check:
2996 Node* GraphKit::type_check_receiver(Node* receiver, ciKlass* klass,
2997 float prob,
2998 Node* *casted_receiver) {
2999 assert(!klass->is_interface(), "no exact type check on interfaces");
3000
3001 const TypeKlassPtr* tklass = TypeKlassPtr::make(klass, Type::trust_interfaces);
3002 Node* recv_klass = load_object_klass(receiver);
3003 Node* want_klass = makecon(tklass);
3004 Node* cmp = _gvn.transform(new CmpPNode(recv_klass, want_klass));
3005 Node* bol = _gvn.transform(new BoolNode(cmp, BoolTest::eq));
3006 IfNode* iff = create_and_xform_if(control(), bol, prob, COUNT_UNKNOWN);
3007 set_control( _gvn.transform(new IfTrueNode (iff)));
3008 Node* fail = _gvn.transform(new IfFalseNode(iff));
3009
3010 if (!stopped()) {
3011 const TypeOopPtr* receiver_type = _gvn.type(receiver)->isa_oopptr();
3012 const TypeOopPtr* recvx_type = tklass->as_instance_type();
3013 assert(recvx_type->klass_is_exact(), "");
3014
3015 if (!receiver_type->higher_equal(recvx_type)) { // ignore redundant casts
3016 // Subsume downstream occurrences of receiver with a cast to
3017 // recv_xtype, since now we know what the type will be.
3018 Node* cast = new CheckCastPPNode(control(), receiver, recvx_type);
3019 (*casted_receiver) = _gvn.transform(cast);
3020 assert(!(*casted_receiver)->is_top(), "that path should be unreachable");
3021 // (User must make the replace_in_map call.)
3022 }
3023 }
3024
3025 return fail;
3026 }
3027
3028 //------------------------------subtype_check_receiver-------------------------
3029 Node* GraphKit::subtype_check_receiver(Node* receiver, ciKlass* klass,
3030 Node** casted_receiver) {
3031 const TypeKlassPtr* tklass = TypeKlassPtr::make(klass, Type::trust_interfaces)->try_improve();
3032 Node* want_klass = makecon(tklass);
3033
3034 Node* slow_ctl = gen_subtype_check(receiver, want_klass);
3035
3036 // Ignore interface type information until interface types are properly tracked.
3037 if (!stopped() && !klass->is_interface()) {
3038 const TypeOopPtr* receiver_type = _gvn.type(receiver)->isa_oopptr();
3039 const TypeOopPtr* recv_type = tklass->cast_to_exactness(false)->is_klassptr()->as_instance_type();
3040 if (!receiver_type->higher_equal(recv_type)) { // ignore redundant casts
3041 Node* cast = new CheckCastPPNode(control(), receiver, recv_type);
3042 (*casted_receiver) = _gvn.transform(cast);
3043 }
3044 }
3045
3046 return slow_ctl;
3047 }
3048
3049 //------------------------------seems_never_null-------------------------------
3050 // Use null_seen information if it is available from the profile.
3051 // If we see an unexpected null at a type check we record it and force a
3052 // recompile; the offending check will be recompiled to handle nulls.
3053 // If we see several offending BCIs, then all checks in the
3054 // method will be recompiled.
3055 bool GraphKit::seems_never_null(Node* obj, ciProfileData* data, bool& speculating) {
3056 speculating = !_gvn.type(obj)->speculative_maybe_null();
3057 Deoptimization::DeoptReason reason = Deoptimization::reason_null_check(speculating);
3058 if (UncommonNullCast // Cutout for this technique
3059 && obj != null() // And not the -Xcomp stupid case?
3060 && !too_many_traps(reason)
3061 ) {
3062 if (speculating) {
3063 return true;
3064 }
3065 if (data == nullptr)
3066 // Edge case: no mature data. Be optimistic here.
3067 return true;
3068 // If the profile has not seen a null, assume it won't happen.
3069 assert(java_bc() == Bytecodes::_checkcast ||
3070 java_bc() == Bytecodes::_instanceof ||
3071 java_bc() == Bytecodes::_aastore, "MDO must collect null_seen bit here");
3072 return !data->as_BitData()->null_seen();
3073 }
3074 speculating = false;
3075 return false;
3076 }
3077
3078 void GraphKit::guard_klass_being_initialized(Node* klass) {
3079 int init_state_off = in_bytes(InstanceKlass::init_state_offset());
3080 Node* adr = off_heap_plus_addr(klass, init_state_off);
3081 Node* init_state = LoadNode::make(_gvn, nullptr, immutable_memory(), adr,
3082 adr->bottom_type()->is_ptr(), TypeInt::BYTE,
3083 T_BYTE, MemNode::acquire);
3084 init_state = _gvn.transform(init_state);
3085
3086 Node* being_initialized_state = makecon(TypeInt::make(InstanceKlass::being_initialized));
3087
3088 Node* chk = _gvn.transform(new CmpINode(being_initialized_state, init_state));
3089 Node* tst = _gvn.transform(new BoolNode(chk, BoolTest::eq));
3090
3091 { BuildCutout unless(this, tst, PROB_MAX);
3092 uncommon_trap(Deoptimization::Reason_initialized, Deoptimization::Action_reinterpret);
3093 }
3094 }
3095
3096 void GraphKit::guard_init_thread(Node* klass) {
3097 int init_thread_off = in_bytes(InstanceKlass::init_thread_offset());
3098 Node* adr = off_heap_plus_addr(klass, init_thread_off);
3099
3100 Node* init_thread = LoadNode::make(_gvn, nullptr, immutable_memory(), adr,
3101 adr->bottom_type()->is_ptr(), TypePtr::NOTNULL,
3102 T_ADDRESS, MemNode::unordered);
3103 init_thread = _gvn.transform(init_thread);
3104
3105 Node* cur_thread = _gvn.transform(new ThreadLocalNode());
3106
3107 Node* chk = _gvn.transform(new CmpPNode(cur_thread, init_thread));
3108 Node* tst = _gvn.transform(new BoolNode(chk, BoolTest::eq));
3109
3110 { BuildCutout unless(this, tst, PROB_MAX);
3111 uncommon_trap(Deoptimization::Reason_uninitialized, Deoptimization::Action_none);
3112 }
3113 }
3114
3115 void GraphKit::clinit_barrier(ciInstanceKlass* ik, ciMethod* context) {
3116 if (ik->is_being_initialized()) {
3117 if (C->needs_clinit_barrier(ik, context)) {
3118 Node* klass = makecon(TypeKlassPtr::make(ik));
3119 guard_klass_being_initialized(klass);
3120 guard_init_thread(klass);
3121 insert_mem_bar(Op_MemBarCPUOrder);
3122 }
3123 } else if (ik->is_initialized()) {
3124 return; // no barrier needed
3125 } else {
3126 uncommon_trap(Deoptimization::Reason_uninitialized,
3127 Deoptimization::Action_reinterpret,
3128 nullptr);
3129 }
3130 }
3131
3132 //------------------------maybe_cast_profiled_receiver-------------------------
3133 // If the profile has seen exactly one type, narrow to exactly that type.
3134 // Subsequent type checks will always fold up.
3135 Node* GraphKit::maybe_cast_profiled_receiver(Node* not_null_obj,
3136 const TypeKlassPtr* require_klass,
3137 ciKlass* spec_klass,
3138 bool safe_for_replace) {
3139 if (!UseTypeProfile || !TypeProfileCasts) return nullptr;
3140
3141 Deoptimization::DeoptReason reason = Deoptimization::reason_class_check(spec_klass != nullptr);
3142
3143 // Make sure we haven't already deoptimized from this tactic.
3144 if (too_many_traps_or_recompiles(reason))
3145 return nullptr;
3146
3147 // (No, this isn't a call, but it's enough like a virtual call
3148 // to use the same ciMethod accessor to get the profile info...)
3149 // If we have a speculative type use it instead of profiling (which
3150 // may not help us)
3151 ciKlass* exact_kls = spec_klass == nullptr ? profile_has_unique_klass() : spec_klass;
3152 if (exact_kls != nullptr) {// no cast failures here
3153 if (require_klass == nullptr ||
3154 C->static_subtype_check(require_klass, TypeKlassPtr::make(exact_kls, Type::trust_interfaces)) == Compile::SSC_always_true) {
3155 // If we narrow the type to match what the type profile sees or
3156 // the speculative type, we can then remove the rest of the
3157 // cast.
3158 // This is a win, even if the exact_kls is very specific,
3159 // because downstream operations, such as method calls,
3160 // will often benefit from the sharper type.
3161 Node* exact_obj = not_null_obj; // will get updated in place...
3162 Node* slow_ctl = type_check_receiver(exact_obj, exact_kls, 1.0,
3163 &exact_obj);
3164 { PreserveJVMState pjvms(this);
3165 set_control(slow_ctl);
3166 uncommon_trap_exact(reason, Deoptimization::Action_maybe_recompile);
3167 }
3168 if (safe_for_replace) {
3169 replace_in_map(not_null_obj, exact_obj);
3170 }
3171 return exact_obj;
3172 }
3173 // assert(ssc == Compile::SSC_always_true)... except maybe the profile lied to us.
3174 }
3175
3176 return nullptr;
3177 }
3178
3179 /**
3180 * Cast obj to type and emit guard unless we had too many traps here
3181 * already
3182 *
3183 * @param obj node being casted
3184 * @param type type to cast the node to
3185 * @param not_null true if we know node cannot be null
3186 */
3187 Node* GraphKit::maybe_cast_profiled_obj(Node* obj,
3188 ciKlass* type,
3189 bool not_null) {
3190 if (stopped()) {
3191 return obj;
3192 }
3193
3194 // type is null if profiling tells us this object is always null
3195 if (type != nullptr) {
3196 Deoptimization::DeoptReason class_reason = Deoptimization::Reason_speculate_class_check;
3197 Deoptimization::DeoptReason null_reason = Deoptimization::Reason_speculate_null_check;
3198
3199 if (!too_many_traps_or_recompiles(null_reason) &&
3200 !too_many_traps_or_recompiles(class_reason)) {
3201 Node* not_null_obj = nullptr;
3202 // not_null is true if we know the object is not null and
3203 // there's no need for a null check
3204 if (!not_null) {
3205 Node* null_ctl = top();
3206 not_null_obj = null_check_oop(obj, &null_ctl, true, true, true);
3207 assert(null_ctl->is_top(), "no null control here");
3208 } else {
3209 not_null_obj = obj;
3210 }
3211
3212 Node* exact_obj = not_null_obj;
3213 ciKlass* exact_kls = type;
3214 Node* slow_ctl = type_check_receiver(exact_obj, exact_kls, 1.0,
3215 &exact_obj);
3216 {
3217 PreserveJVMState pjvms(this);
3218 set_control(slow_ctl);
3219 uncommon_trap_exact(class_reason, Deoptimization::Action_maybe_recompile);
3220 }
3221 replace_in_map(not_null_obj, exact_obj);
3222 obj = exact_obj;
3223 }
3224 } else {
3225 if (!too_many_traps_or_recompiles(Deoptimization::Reason_null_assert)) {
3226 Node* exact_obj = null_assert(obj);
3227 replace_in_map(obj, exact_obj);
3228 obj = exact_obj;
3229 }
3230 }
3231 return obj;
3232 }
3233
3234 //-------------------------------gen_instanceof--------------------------------
3235 // Generate an instance-of idiom. Used by both the instance-of bytecode
3236 // and the reflective instance-of call.
3237 Node* GraphKit::gen_instanceof(Node* obj, Node* superklass, bool safe_for_replace) {
3238 kill_dead_locals(); // Benefit all the uncommon traps
3239 assert( !stopped(), "dead parse path should be checked in callers" );
3240 assert(!TypePtr::NULL_PTR->higher_equal(_gvn.type(superklass)->is_klassptr()),
3241 "must check for not-null not-dead klass in callers");
3242
3243 // Make the merge point
3244 enum { _obj_path = 1, _fail_path, _null_path, PATH_LIMIT };
3245 RegionNode* region = new RegionNode(PATH_LIMIT);
3246 Node* phi = new PhiNode(region, TypeInt::BOOL);
3247 C->set_has_split_ifs(true); // Has chance for split-if optimization
3248
3249 ciProfileData* data = nullptr;
3250 if (java_bc() == Bytecodes::_instanceof) { // Only for the bytecode
3251 data = method()->method_data()->bci_to_data(bci());
3252 }
3253 bool speculative_not_null = false;
3254 bool never_see_null = (ProfileDynamicTypes // aggressive use of profile
3255 && seems_never_null(obj, data, speculative_not_null));
3256
3257 // Null check; get casted pointer; set region slot 3
3258 Node* null_ctl = top();
3259 Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace, speculative_not_null);
3260
3261 // If not_null_obj is dead, only null-path is taken
3262 if (stopped()) { // Doing instance-of on a null?
3263 set_control(null_ctl);
3264 return intcon(0);
3265 }
3266 region->init_req(_null_path, null_ctl);
3267 phi ->init_req(_null_path, intcon(0)); // Set null path value
3268 if (null_ctl == top()) {
3269 // Do this eagerly, so that pattern matches like is_diamond_phi
3270 // will work even during parsing.
3271 assert(_null_path == PATH_LIMIT-1, "delete last");
3272 region->del_req(_null_path);
3273 phi ->del_req(_null_path);
3274 }
3275
3276 // Do we know the type check always succeed?
3277 bool known_statically = false;
3278 if (_gvn.type(superklass)->singleton()) {
3279 const TypeKlassPtr* superk = _gvn.type(superklass)->is_klassptr();
3280 const TypeKlassPtr* subk = _gvn.type(obj)->is_oopptr()->as_klass_type();
3281 if (subk->is_loaded()) {
3282 int static_res = C->static_subtype_check(superk, subk);
3283 known_statically = (static_res == Compile::SSC_always_true || static_res == Compile::SSC_always_false);
3284 }
3285 }
3286
3287 if (!known_statically) {
3288 const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
3289 // We may not have profiling here or it may not help us. If we
3290 // have a speculative type use it to perform an exact cast.
3291 ciKlass* spec_obj_type = obj_type->speculative_type();
3292 if (spec_obj_type != nullptr || (ProfileDynamicTypes && data != nullptr)) {
3293 Node* cast_obj = maybe_cast_profiled_receiver(not_null_obj, nullptr, spec_obj_type, safe_for_replace);
3294 if (stopped()) { // Profile disagrees with this path.
3295 set_control(null_ctl); // Null is the only remaining possibility.
3296 return intcon(0);
3297 }
3298 if (cast_obj != nullptr) {
3299 not_null_obj = cast_obj;
3300 }
3301 }
3302 }
3303
3304 // Generate the subtype check
3305 Node* not_subtype_ctrl = gen_subtype_check(not_null_obj, superklass);
3306
3307 // Plug in the success path to the general merge in slot 1.
3308 region->init_req(_obj_path, control());
3309 phi ->init_req(_obj_path, intcon(1));
3310
3311 // Plug in the failing path to the general merge in slot 2.
3312 region->init_req(_fail_path, not_subtype_ctrl);
3313 phi ->init_req(_fail_path, intcon(0));
3314
3315 // Return final merged results
3316 set_control( _gvn.transform(region) );
3317 record_for_igvn(region);
3318
3319 // If we know the type check always succeeds then we don't use the
3320 // profiling data at this bytecode. Don't lose it, feed it to the
3321 // type system as a speculative type.
3322 if (safe_for_replace) {
3323 Node* casted_obj = record_profiled_receiver_for_speculation(obj);
3324 replace_in_map(obj, casted_obj);
3325 }
3326
3327 return _gvn.transform(phi);
3328 }
3329
3330 //-------------------------------gen_checkcast---------------------------------
3331 // Generate a checkcast idiom. Used by both the checkcast bytecode and the
3332 // array store bytecode. Stack must be as-if BEFORE doing the bytecode so the
3333 // uncommon-trap paths work. Adjust stack after this call.
3334 // If failure_control is supplied and not null, it is filled in with
3335 // the control edge for the cast failure. Otherwise, an appropriate
3336 // uncommon trap or exception is thrown.
3337 Node* GraphKit::gen_checkcast(Node *obj, Node* superklass,
3338 Node* *failure_control) {
3339 kill_dead_locals(); // Benefit all the uncommon traps
3340 const TypeKlassPtr* klass_ptr_type = _gvn.type(superklass)->is_klassptr();
3341 const TypeKlassPtr* improved_klass_ptr_type = klass_ptr_type->try_improve();
3342 const TypeOopPtr* toop = improved_klass_ptr_type->cast_to_exactness(false)->as_instance_type();
3343
3344 // Fast cutout: Check the case that the cast is vacuously true.
3345 // This detects the common cases where the test will short-circuit
3346 // away completely. We do this before we perform the null check,
3347 // because if the test is going to turn into zero code, we don't
3348 // want a residual null check left around. (Causes a slowdown,
3349 // for example, in some objArray manipulations, such as a[i]=a[j].)
3350 if (improved_klass_ptr_type->singleton()) {
3351 const TypeOopPtr* objtp = _gvn.type(obj)->isa_oopptr();
3352 if (objtp != nullptr) {
3353 switch (C->static_subtype_check(improved_klass_ptr_type, objtp->as_klass_type())) {
3354 case Compile::SSC_always_true:
3355 // If we know the type check always succeed then we don't use
3356 // the profiling data at this bytecode. Don't lose it, feed it
3357 // to the type system as a speculative type.
3358 return record_profiled_receiver_for_speculation(obj);
3359 case Compile::SSC_always_false:
3360 // It needs a null check because a null will *pass* the cast check.
3361 // A non-null value will always produce an exception.
3362 if (!objtp->maybe_null()) {
3363 bool is_aastore = (java_bc() == Bytecodes::_aastore);
3364 Deoptimization::DeoptReason reason = is_aastore ?
3365 Deoptimization::Reason_array_check : Deoptimization::Reason_class_check;
3366 builtin_throw(reason);
3367 return top();
3368 } else if (!too_many_traps_or_recompiles(Deoptimization::Reason_null_assert)) {
3369 return null_assert(obj);
3370 }
3371 break; // Fall through to full check
3372 default:
3373 break;
3374 }
3375 }
3376 }
3377
3378 ciProfileData* data = nullptr;
3379 bool safe_for_replace = false;
3380 if (failure_control == nullptr) { // use MDO in regular case only
3381 assert(java_bc() == Bytecodes::_aastore ||
3382 java_bc() == Bytecodes::_checkcast,
3383 "interpreter profiles type checks only for these BCs");
3384 data = method()->method_data()->bci_to_data(bci());
3385 safe_for_replace = true;
3386 }
3387
3388 // Make the merge point
3389 enum { _obj_path = 1, _null_path, PATH_LIMIT };
3390 RegionNode* region = new RegionNode(PATH_LIMIT);
3391 Node* phi = new PhiNode(region, toop);
3392 C->set_has_split_ifs(true); // Has chance for split-if optimization
3393
3394 // Use null-cast information if it is available
3395 bool speculative_not_null = false;
3396 bool never_see_null = ((failure_control == nullptr) // regular case only
3397 && seems_never_null(obj, data, speculative_not_null));
3398
3399 // Null check; get casted pointer; set region slot 3
3400 Node* null_ctl = top();
3401 Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace, speculative_not_null);
3402
3403 // If not_null_obj is dead, only null-path is taken
3404 if (stopped()) { // Doing instance-of on a null?
3405 set_control(null_ctl);
3406 return null();
3407 }
3408 region->init_req(_null_path, null_ctl);
3409 phi ->init_req(_null_path, null()); // Set null path value
3410 if (null_ctl == top()) {
3411 // Do this eagerly, so that pattern matches like is_diamond_phi
3412 // will work even during parsing.
3413 assert(_null_path == PATH_LIMIT-1, "delete last");
3414 region->del_req(_null_path);
3415 phi ->del_req(_null_path);
3416 }
3417
3418 Node* cast_obj = nullptr;
3419 if (improved_klass_ptr_type->klass_is_exact()) {
3420 // The following optimization tries to statically cast the speculative type of the object
3421 // (for example obtained during profiling) to the type of the superklass and then do a
3422 // dynamic check that the type of the object is what we expect. To work correctly
3423 // for checkcast and aastore the type of superklass should be exact.
3424 const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
3425 // We may not have profiling here or it may not help us. If we have
3426 // a speculative type use it to perform an exact cast.
3427 ciKlass* spec_obj_type = obj_type->speculative_type();
3428 if (spec_obj_type != nullptr || data != nullptr) {
3429 cast_obj = maybe_cast_profiled_receiver(not_null_obj, improved_klass_ptr_type, spec_obj_type, safe_for_replace);
3430 if (cast_obj != nullptr) {
3431 if (failure_control != nullptr) // failure is now impossible
3432 (*failure_control) = top();
3433 // adjust the type of the phi to the exact klass:
3434 phi->raise_bottom_type(_gvn.type(cast_obj)->meet_speculative(TypePtr::NULL_PTR));
3435 }
3436 }
3437 }
3438
3439 if (cast_obj == nullptr) {
3440 // Generate the subtype check
3441 Node* improved_superklass = superklass;
3442 if (improved_klass_ptr_type != klass_ptr_type && improved_klass_ptr_type->singleton()) {
3443 improved_superklass = makecon(improved_klass_ptr_type);
3444 }
3445 Node* not_subtype_ctrl = gen_subtype_check(not_null_obj, improved_superklass);
3446
3447 // Plug in success path into the merge
3448 cast_obj = _gvn.transform(new CheckCastPPNode(control(), not_null_obj, toop));
3449 // Failure path ends in uncommon trap (or may be dead - failure impossible)
3450 if (failure_control == nullptr) {
3451 if (not_subtype_ctrl != top()) { // If failure is possible
3452 PreserveJVMState pjvms(this);
3453 set_control(not_subtype_ctrl);
3454 bool is_aastore = (java_bc() == Bytecodes::_aastore);
3455 Deoptimization::DeoptReason reason = is_aastore ?
3456 Deoptimization::Reason_array_check : Deoptimization::Reason_class_check;
3457 builtin_throw(reason);
3458 }
3459 } else {
3460 (*failure_control) = not_subtype_ctrl;
3461 }
3462 }
3463
3464 region->init_req(_obj_path, control());
3465 phi ->init_req(_obj_path, cast_obj);
3466
3467 // A merge of null or Casted-NotNull obj
3468 Node* res = _gvn.transform(phi);
3469
3470 // Note I do NOT always 'replace_in_map(obj,result)' here.
3471 // if( tk->klass()->can_be_primary_super() )
3472 // This means that if I successfully store an Object into an array-of-String
3473 // I 'forget' that the Object is really now known to be a String. I have to
3474 // do this because we don't have true union types for interfaces - if I store
3475 // a Baz into an array-of-Interface and then tell the optimizer it's an
3476 // Interface, I forget that it's also a Baz and cannot do Baz-like field
3477 // references to it. FIX THIS WHEN UNION TYPES APPEAR!
3478 // replace_in_map( obj, res );
3479
3480 // Return final merged results
3481 set_control( _gvn.transform(region) );
3482 record_for_igvn(region);
3483
3484 return record_profiled_receiver_for_speculation(res);
3485 }
3486
3487 //------------------------------next_monitor-----------------------------------
3488 // What number should be given to the next monitor?
3489 int GraphKit::next_monitor() {
3490 int current = jvms()->monitor_depth()* C->sync_stack_slots();
3491 int next = current + C->sync_stack_slots();
3492 // Keep the toplevel high water mark current:
3493 if (C->fixed_slots() < next) C->set_fixed_slots(next);
3494 return current;
3495 }
3496
3497 //------------------------------insert_mem_bar---------------------------------
3498 // Memory barrier to avoid floating things around
3499 // The membar serves as a pinch point between both control and all memory slices.
3500 Node* GraphKit::insert_mem_bar(int opcode, Node* precedent) {
3501 MemBarNode* mb = MemBarNode::make(C, opcode, Compile::AliasIdxBot, precedent);
3502 mb->init_req(TypeFunc::Control, control());
3503 mb->init_req(TypeFunc::Memory, reset_memory());
3504 Node* membar = _gvn.transform(mb);
3505 record_for_igvn(membar);
3506 set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control)));
3507 set_all_memory_call(membar);
3508 return membar;
3509 }
3510
3511 //-------------------------insert_mem_bar_volatile----------------------------
3512 // Memory barrier to avoid floating things around
3513 // The membar serves as a pinch point between both control and memory(alias_idx).
3514 // If you want to make a pinch point on all memory slices, do not use this
3515 // function (even with AliasIdxBot); use insert_mem_bar() instead.
3516 Node* GraphKit::insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent) {
3517 // When Parse::do_put_xxx updates a volatile field, it appends a series
3518 // of MemBarVolatile nodes, one for *each* volatile field alias category.
3519 // The first membar is on the same memory slice as the field store opcode.
3520 // This forces the membar to follow the store. (Bug 6500685 broke this.)
3521 // All the other membars (for other volatile slices, including AliasIdxBot,
3522 // which stands for all unknown volatile slices) are control-dependent
3523 // on the first membar. This prevents later volatile loads or stores
3524 // from sliding up past the just-emitted store.
3525
3526 MemBarNode* mb = MemBarNode::make(C, opcode, alias_idx, precedent);
3527 mb->set_req(TypeFunc::Control,control());
3528 if (alias_idx == Compile::AliasIdxBot) {
3529 mb->set_req(TypeFunc::Memory, merged_memory()->base_memory());
3530 } else {
3531 assert(!(opcode == Op_Initialize && alias_idx != Compile::AliasIdxRaw), "fix caller");
3532 mb->set_req(TypeFunc::Memory, memory(alias_idx));
3533 }
3534 Node* membar = _gvn.transform(mb);
3535 record_for_igvn(membar);
3536 set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control)));
3537 if (alias_idx == Compile::AliasIdxBot) {
3538 merged_memory()->set_base_memory(_gvn.transform(new ProjNode(membar, TypeFunc::Memory)));
3539 } else {
3540 set_memory(_gvn.transform(new ProjNode(membar, TypeFunc::Memory)),alias_idx);
3541 }
3542 return membar;
3543 }
3544
3545 //------------------------------insert_reachability_fence----------------------
3546 Node* GraphKit::insert_reachability_fence(Node* referent) {
3547 assert(!referent->is_top(), "");
3548 Node* rf = _gvn.transform(new ReachabilityFenceNode(C, control(), referent));
3549 set_control(rf);
3550 C->record_for_igvn(rf);
3551 return rf;
3552 }
3553
3554 //------------------------------shared_lock------------------------------------
3555 // Emit locking code.
3556 FastLockNode* GraphKit::shared_lock(Node* obj) {
3557 // bci is either a monitorenter bc or InvocationEntryBci
3558 // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3559 assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3560
3561 if (stopped()) // Dead monitor?
3562 return nullptr;
3563
3564 assert(dead_locals_are_killed(), "should kill locals before sync. point");
3565
3566 // Box the stack location
3567 Node* box = new BoxLockNode(next_monitor());
3568 // Check for bailout after new BoxLockNode
3569 if (failing()) { return nullptr; }
3570 box = _gvn.transform(box);
3571 Node* mem = reset_memory();
3572
3573 FastLockNode * flock = _gvn.transform(new FastLockNode(nullptr, obj, box) )->as_FastLock();
3574
3575 // Add monitor to debug info for the slow path. If we block inside the
3576 // slow path and de-opt, we need the monitor hanging around
3577 map()->push_monitor( flock );
3578
3579 const TypeFunc *tf = LockNode::lock_type();
3580 LockNode *lock = new LockNode(C, tf);
3581
3582 lock->init_req( TypeFunc::Control, control() );
3583 lock->init_req( TypeFunc::Memory , mem );
3584 lock->init_req( TypeFunc::I_O , top() ) ; // does no i/o
3585 lock->init_req( TypeFunc::FramePtr, frameptr() );
3586 lock->init_req( TypeFunc::ReturnAdr, top() );
3587
3588 lock->init_req(TypeFunc::Parms + 0, obj);
3589 lock->init_req(TypeFunc::Parms + 1, box);
3590 lock->init_req(TypeFunc::Parms + 2, flock);
3591 add_safepoint_edges(lock);
3592
3593 lock = _gvn.transform( lock )->as_Lock();
3594
3595 // lock has no side-effects, sets few values
3596 set_predefined_output_for_runtime_call(lock, mem, TypeRawPtr::BOTTOM);
3597
3598 insert_mem_bar(Op_MemBarAcquireLock);
3599
3600 // Add this to the worklist so that the lock can be eliminated
3601 record_for_igvn(lock);
3602
3603 #ifndef PRODUCT
3604 if (PrintLockStatistics) {
3605 // Update the counter for this lock. Don't bother using an atomic
3606 // operation since we don't require absolute accuracy.
3607 lock->create_lock_counter(map()->jvms());
3608 increment_counter(lock->counter()->addr());
3609 }
3610 #endif
3611
3612 return flock;
3613 }
3614
3615
3616 //------------------------------shared_unlock----------------------------------
3617 // Emit unlocking code.
3618 void GraphKit::shared_unlock(Node* box, Node* obj) {
3619 // bci is either a monitorenter bc or InvocationEntryBci
3620 // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3621 assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3622
3623 if (stopped()) { // Dead monitor?
3624 map()->pop_monitor(); // Kill monitor from debug info
3625 return;
3626 }
3627
3628 // Memory barrier to avoid floating things down past the locked region
3629 insert_mem_bar(Op_MemBarReleaseLock);
3630
3631 const TypeFunc *tf = OptoRuntime::complete_monitor_exit_Type();
3632 UnlockNode *unlock = new UnlockNode(C, tf);
3633 #ifdef ASSERT
3634 unlock->set_dbg_jvms(sync_jvms());
3635 #endif
3636 uint raw_idx = Compile::AliasIdxRaw;
3637 unlock->init_req( TypeFunc::Control, control() );
3638 unlock->init_req( TypeFunc::Memory , memory(raw_idx) );
3639 unlock->init_req( TypeFunc::I_O , top() ) ; // does no i/o
3640 unlock->init_req( TypeFunc::FramePtr, frameptr() );
3641 unlock->init_req( TypeFunc::ReturnAdr, top() );
3642
3643 unlock->init_req(TypeFunc::Parms + 0, obj);
3644 unlock->init_req(TypeFunc::Parms + 1, box);
3645 unlock = _gvn.transform(unlock)->as_Unlock();
3646
3647 Node* mem = reset_memory();
3648
3649 // unlock has no side-effects, sets few values
3650 set_predefined_output_for_runtime_call(unlock, mem, TypeRawPtr::BOTTOM);
3651
3652 // Kill monitor from debug info
3653 map()->pop_monitor( );
3654 }
3655
3656 //-------------------------------get_layout_helper-----------------------------
3657 // If the given klass is a constant or known to be an array,
3658 // fetch the constant layout helper value into constant_value
3659 // and return null. Otherwise, load the non-constant
3660 // layout helper value, and return the node which represents it.
3661 // This two-faced routine is useful because allocation sites
3662 // almost always feature constant types.
3663 Node* GraphKit::get_layout_helper(Node* klass_node, jint& constant_value) {
3664 const TypeKlassPtr* klass_t = _gvn.type(klass_node)->isa_klassptr();
3665 if (!StressReflectiveCode && klass_t != nullptr) {
3666 bool xklass = klass_t->klass_is_exact();
3667 if (xklass || (klass_t->isa_aryklassptr() && klass_t->is_aryklassptr()->elem() != Type::BOTTOM)) {
3668 jint lhelper;
3669 if (klass_t->isa_aryklassptr()) {
3670 BasicType elem = klass_t->as_instance_type()->isa_aryptr()->elem()->array_element_basic_type();
3671 if (is_reference_type(elem, true)) {
3672 elem = T_OBJECT;
3673 }
3674 lhelper = Klass::array_layout_helper(elem);
3675 } else {
3676 lhelper = klass_t->is_instklassptr()->exact_klass()->layout_helper();
3677 }
3678 if (lhelper != Klass::_lh_neutral_value) {
3679 constant_value = lhelper;
3680 return (Node*) nullptr;
3681 }
3682 }
3683 }
3684 constant_value = Klass::_lh_neutral_value; // put in a known value
3685 Node* lhp = off_heap_plus_addr(klass_node, in_bytes(Klass::layout_helper_offset()));
3686 return make_load(nullptr, lhp, TypeInt::INT, T_INT, MemNode::unordered);
3687 }
3688
3689 // We just put in an allocate/initialize with a big raw-memory effect.
3690 // Hook selected additional alias categories on the initialization.
3691 static void hook_memory_on_init(GraphKit& kit, int alias_idx,
3692 MergeMemNode* init_in_merge,
3693 Node* init_out_raw) {
3694 DEBUG_ONLY(Node* init_in_raw = init_in_merge->base_memory());
3695 assert(init_in_merge->memory_at(alias_idx) == init_in_raw, "");
3696
3697 Node* prevmem = kit.memory(alias_idx);
3698 init_in_merge->set_memory_at(alias_idx, prevmem);
3699 kit.set_memory(init_out_raw, alias_idx);
3700 }
3701
3702 //---------------------------set_output_for_allocation-------------------------
3703 Node* GraphKit::set_output_for_allocation(AllocateNode* alloc,
3704 const TypeOopPtr* oop_type,
3705 bool deoptimize_on_exception) {
3706 int rawidx = Compile::AliasIdxRaw;
3707 alloc->set_req( TypeFunc::FramePtr, frameptr() );
3708 add_safepoint_edges(alloc);
3709 Node* allocx = _gvn.transform(alloc);
3710 set_control( _gvn.transform(new ProjNode(allocx, TypeFunc::Control) ) );
3711 // create memory projection for i_o
3712 set_memory ( _gvn.transform( new ProjNode(allocx, TypeFunc::Memory, true) ), rawidx );
3713 make_slow_call_ex(allocx, env()->Throwable_klass(), true, deoptimize_on_exception);
3714
3715 // create a memory projection as for the normal control path
3716 Node* malloc = _gvn.transform(new ProjNode(allocx, TypeFunc::Memory));
3717 set_memory(malloc, rawidx);
3718
3719 // a normal slow-call doesn't change i_o, but an allocation does
3720 // we create a separate i_o projection for the normal control path
3721 set_i_o(_gvn.transform( new ProjNode(allocx, TypeFunc::I_O, false) ) );
3722 Node* rawoop = _gvn.transform( new ProjNode(allocx, TypeFunc::Parms) );
3723
3724 // put in an initialization barrier
3725 InitializeNode* init = insert_mem_bar_volatile(Op_Initialize, rawidx,
3726 rawoop)->as_Initialize();
3727 assert(alloc->initialization() == init, "2-way macro link must work");
3728 assert(init ->allocation() == alloc, "2-way macro link must work");
3729 {
3730 // Extract memory strands which may participate in the new object's
3731 // initialization, and source them from the new InitializeNode.
3732 // This will allow us to observe initializations when they occur,
3733 // and link them properly (as a group) to the InitializeNode.
3734 assert(init->in(InitializeNode::Memory) == malloc, "");
3735 MergeMemNode* minit_in = MergeMemNode::make(malloc);
3736 init->set_req(InitializeNode::Memory, minit_in);
3737 record_for_igvn(minit_in); // fold it up later, if possible
3738 Node* minit_out = memory(rawidx);
3739 assert(minit_out->is_Proj() && minit_out->in(0) == init, "");
3740 int mark_idx = C->get_alias_index(oop_type->add_offset(oopDesc::mark_offset_in_bytes()));
3741 // Add an edge in the MergeMem for the header fields so an access to one of those has correct memory state.
3742 // Use one NarrowMemProjNode per slice to properly record the adr type of each slice. The Initialize node will have
3743 // multiple projections as a result.
3744 set_memory(_gvn.transform(new NarrowMemProjNode(init, C->get_adr_type(mark_idx))), mark_idx);
3745 int klass_idx = C->get_alias_index(oop_type->add_offset(oopDesc::klass_offset_in_bytes()));
3746 set_memory(_gvn.transform(new NarrowMemProjNode(init, C->get_adr_type(klass_idx))), klass_idx);
3747 if (oop_type->isa_aryptr()) {
3748 const TypePtr* telemref = oop_type->add_offset(Type::OffsetBot);
3749 int elemidx = C->get_alias_index(telemref);
3750 hook_memory_on_init(*this, elemidx, minit_in, _gvn.transform(new NarrowMemProjNode(init, C->get_adr_type(elemidx))));
3751 } else if (oop_type->isa_instptr()) {
3752 ciInstanceKlass* ik = oop_type->is_instptr()->instance_klass();
3753 for (int i = 0, len = ik->nof_nonstatic_fields(); i < len; i++) {
3754 ciField* field = ik->nonstatic_field_at(i);
3755 if (field->offset_in_bytes() >= TrackedInitializationLimit * HeapWordSize)
3756 continue; // do not bother to track really large numbers of fields
3757 // Find (or create) the alias category for this field:
3758 int fieldidx = C->alias_type(field)->index();
3759 hook_memory_on_init(*this, fieldidx, minit_in, _gvn.transform(new NarrowMemProjNode(init, C->get_adr_type(fieldidx))));
3760 }
3761 }
3762 }
3763
3764 // Cast raw oop to the real thing...
3765 Node* javaoop = new CheckCastPPNode(control(), rawoop, oop_type);
3766 javaoop = _gvn.transform(javaoop);
3767 C->set_recent_alloc(control(), javaoop);
3768 assert(just_allocated_object(control()) == javaoop, "just allocated");
3769
3770 #ifdef ASSERT
3771 { // Verify that the AllocateNode::Ideal_allocation recognizers work:
3772 assert(AllocateNode::Ideal_allocation(rawoop) == alloc,
3773 "Ideal_allocation works");
3774 assert(AllocateNode::Ideal_allocation(javaoop) == alloc,
3775 "Ideal_allocation works");
3776 if (alloc->is_AllocateArray()) {
3777 assert(AllocateArrayNode::Ideal_array_allocation(rawoop) == alloc->as_AllocateArray(),
3778 "Ideal_allocation works");
3779 assert(AllocateArrayNode::Ideal_array_allocation(javaoop) == alloc->as_AllocateArray(),
3780 "Ideal_allocation works");
3781 } else {
3782 assert(alloc->in(AllocateNode::ALength)->is_top(), "no length, please");
3783 }
3784 }
3785 #endif //ASSERT
3786
3787 return javaoop;
3788 }
3789
3790 //---------------------------new_instance--------------------------------------
3791 // This routine takes a klass_node which may be constant (for a static type)
3792 // or may be non-constant (for reflective code). It will work equally well
3793 // for either, and the graph will fold nicely if the optimizer later reduces
3794 // the type to a constant.
3795 // The optional arguments are for specialized use by intrinsics:
3796 // - If 'extra_slow_test' if not null is an extra condition for the slow-path.
3797 // - If 'return_size_val', report the total object size to the caller.
3798 // - deoptimize_on_exception controls how Java exceptions are handled (rethrow vs deoptimize)
3799 Node* GraphKit::new_instance(Node* klass_node,
3800 Node* extra_slow_test,
3801 Node* *return_size_val,
3802 bool deoptimize_on_exception) {
3803 // Compute size in doublewords
3804 // The size is always an integral number of doublewords, represented
3805 // as a positive bytewise size stored in the klass's layout_helper.
3806 // The layout_helper also encodes (in a low bit) the need for a slow path.
3807 jint layout_con = Klass::_lh_neutral_value;
3808 Node* layout_val = get_layout_helper(klass_node, layout_con);
3809 int layout_is_con = (layout_val == nullptr);
3810
3811 if (extra_slow_test == nullptr) extra_slow_test = intcon(0);
3812 // Generate the initial go-slow test. It's either ALWAYS (return a
3813 // Node for 1) or NEVER (return a null) or perhaps (in the reflective
3814 // case) a computed value derived from the layout_helper.
3815 Node* initial_slow_test = nullptr;
3816 if (layout_is_con) {
3817 assert(!StressReflectiveCode, "stress mode does not use these paths");
3818 bool must_go_slow = Klass::layout_helper_needs_slow_path(layout_con);
3819 initial_slow_test = must_go_slow ? intcon(1) : extra_slow_test;
3820 } else { // reflective case
3821 // This reflective path is used by Unsafe.allocateInstance.
3822 // (It may be stress-tested by specifying StressReflectiveCode.)
3823 // Basically, we want to get into the VM is there's an illegal argument.
3824 Node* bit = intcon(Klass::_lh_instance_slow_path_bit);
3825 initial_slow_test = _gvn.transform( new AndINode(layout_val, bit) );
3826 if (extra_slow_test != intcon(0)) {
3827 initial_slow_test = _gvn.transform( new OrINode(initial_slow_test, extra_slow_test) );
3828 }
3829 // (Macro-expander will further convert this to a Bool, if necessary.)
3830 }
3831
3832 // Find the size in bytes. This is easy; it's the layout_helper.
3833 // The size value must be valid even if the slow path is taken.
3834 Node* size = nullptr;
3835 if (layout_is_con) {
3836 size = MakeConX(Klass::layout_helper_size_in_bytes(layout_con));
3837 } else { // reflective case
3838 // This reflective path is used by clone and Unsafe.allocateInstance.
3839 size = ConvI2X(layout_val);
3840
3841 // Clear the low bits to extract layout_helper_size_in_bytes:
3842 assert((int)Klass::_lh_instance_slow_path_bit < BytesPerLong, "clear bit");
3843 Node* mask = MakeConX(~ (intptr_t)right_n_bits(LogBytesPerLong));
3844 size = _gvn.transform( new AndXNode(size, mask) );
3845 }
3846 if (return_size_val != nullptr) {
3847 (*return_size_val) = size;
3848 }
3849
3850 // This is a precise notnull oop of the klass.
3851 // (Actually, it need not be precise if this is a reflective allocation.)
3852 // It's what we cast the result to.
3853 const TypeKlassPtr* tklass = _gvn.type(klass_node)->isa_klassptr();
3854 if (!tklass) tklass = TypeInstKlassPtr::OBJECT;
3855 const TypeOopPtr* oop_type = tklass->as_instance_type();
3856
3857 // Now generate allocation code
3858
3859 // The entire memory state is needed for slow path of the allocation
3860 // since GC and deoptimization can happened.
3861 Node *mem = reset_memory();
3862 set_all_memory(mem); // Create new memory state
3863
3864 AllocateNode* alloc = new AllocateNode(C, AllocateNode::alloc_type(Type::TOP),
3865 control(), mem, i_o(),
3866 size, klass_node,
3867 initial_slow_test);
3868
3869 return set_output_for_allocation(alloc, oop_type, deoptimize_on_exception);
3870 }
3871
3872 //-------------------------------new_array-------------------------------------
3873 // helper for both newarray and anewarray
3874 // The 'length' parameter is (obviously) the length of the array.
3875 // The optional arguments are for specialized use by intrinsics:
3876 // - If 'return_size_val', report the non-padded array size (sum of header size
3877 // and array body) to the caller.
3878 // - deoptimize_on_exception controls how Java exceptions are handled (rethrow vs deoptimize)
3879 Node* GraphKit::new_array(Node* klass_node, // array klass (maybe variable)
3880 Node* length, // number of array elements
3881 int nargs, // number of arguments to push back for uncommon trap
3882 Node* *return_size_val,
3883 bool deoptimize_on_exception) {
3884 jint layout_con = Klass::_lh_neutral_value;
3885 Node* layout_val = get_layout_helper(klass_node, layout_con);
3886 int layout_is_con = (layout_val == nullptr);
3887
3888 if (!layout_is_con && !StressReflectiveCode &&
3889 !too_many_traps(Deoptimization::Reason_class_check)) {
3890 // This is a reflective array creation site.
3891 // Optimistically assume that it is a subtype of Object[],
3892 // so that we can fold up all the address arithmetic.
3893 layout_con = Klass::array_layout_helper(T_OBJECT);
3894 Node* cmp_lh = _gvn.transform( new CmpINode(layout_val, intcon(layout_con)) );
3895 Node* bol_lh = _gvn.transform( new BoolNode(cmp_lh, BoolTest::eq) );
3896 { BuildCutout unless(this, bol_lh, PROB_MAX);
3897 inc_sp(nargs);
3898 uncommon_trap(Deoptimization::Reason_class_check,
3899 Deoptimization::Action_maybe_recompile);
3900 }
3901 layout_val = nullptr;
3902 layout_is_con = true;
3903 }
3904
3905 // Generate the initial go-slow test. Make sure we do not overflow
3906 // if length is huge (near 2Gig) or negative! We do not need
3907 // exact double-words here, just a close approximation of needed
3908 // double-words. We can't add any offset or rounding bits, lest we
3909 // take a size -1 of bytes and make it positive. Use an unsigned
3910 // compare, so negative sizes look hugely positive.
3911 int fast_size_limit = FastAllocateSizeLimit;
3912 if (layout_is_con) {
3913 assert(!StressReflectiveCode, "stress mode does not use these paths");
3914 // Increase the size limit if we have exact knowledge of array type.
3915 int log2_esize = Klass::layout_helper_log2_element_size(layout_con);
3916 assert(fast_size_limit == 0 || count_leading_zeros(fast_size_limit) > static_cast<unsigned>(LogBytesPerLong - log2_esize),
3917 "fast_size_limit (%d) overflow when shifted left by %d", fast_size_limit, LogBytesPerLong - log2_esize);
3918 fast_size_limit <<= (LogBytesPerLong - log2_esize);
3919 }
3920
3921 Node* initial_slow_cmp = _gvn.transform( new CmpUNode( length, intcon( fast_size_limit ) ) );
3922 Node* initial_slow_test = _gvn.transform( new BoolNode( initial_slow_cmp, BoolTest::gt ) );
3923
3924 // --- Size Computation ---
3925 // array_size = round_to_heap(array_header + (length << elem_shift));
3926 // where round_to_heap(x) == align_to(x, MinObjAlignmentInBytes)
3927 // and align_to(x, y) == ((x + y-1) & ~(y-1))
3928 // The rounding mask is strength-reduced, if possible.
3929 int round_mask = MinObjAlignmentInBytes - 1;
3930 Node* header_size = nullptr;
3931 // (T_BYTE has the weakest alignment and size restrictions...)
3932 if (layout_is_con) {
3933 int hsize = Klass::layout_helper_header_size(layout_con);
3934 int eshift = Klass::layout_helper_log2_element_size(layout_con);
3935 if ((round_mask & ~right_n_bits(eshift)) == 0)
3936 round_mask = 0; // strength-reduce it if it goes away completely
3937 assert((hsize & right_n_bits(eshift)) == 0, "hsize is pre-rounded");
3938 int header_size_min = arrayOopDesc::base_offset_in_bytes(T_BYTE);
3939 assert(header_size_min <= hsize, "generic minimum is smallest");
3940 header_size = intcon(hsize);
3941 } else {
3942 Node* hss = intcon(Klass::_lh_header_size_shift);
3943 Node* hsm = intcon(Klass::_lh_header_size_mask);
3944 header_size = _gvn.transform(new URShiftINode(layout_val, hss));
3945 header_size = _gvn.transform(new AndINode(header_size, hsm));
3946 }
3947
3948 Node* elem_shift = nullptr;
3949 if (layout_is_con) {
3950 int eshift = Klass::layout_helper_log2_element_size(layout_con);
3951 if (eshift != 0)
3952 elem_shift = intcon(eshift);
3953 } else {
3954 // There is no need to mask or shift this value.
3955 // The semantics of LShiftINode include an implicit mask to 0x1F.
3956 assert(Klass::_lh_log2_element_size_shift == 0, "use shift in place");
3957 elem_shift = layout_val;
3958 }
3959
3960 // Transition to native address size for all offset calculations:
3961 Node* lengthx = ConvI2X(length);
3962 Node* headerx = ConvI2X(header_size);
3963 #ifdef _LP64
3964 { const TypeInt* tilen = _gvn.find_int_type(length);
3965 if (tilen != nullptr && tilen->_lo < 0) {
3966 // Add a manual constraint to a positive range. Cf. array_element_address.
3967 jint size_max = fast_size_limit;
3968 if (size_max > tilen->_hi && tilen->_hi >= 0) {
3969 size_max = tilen->_hi;
3970 }
3971 const TypeInt* tlcon = TypeInt::make(0, size_max, Type::WidenMin);
3972
3973 // Only do a narrow I2L conversion if the range check passed.
3974 IfNode* iff = new IfNode(control(), initial_slow_test, PROB_MIN, COUNT_UNKNOWN);
3975 _gvn.transform(iff);
3976 RegionNode* region = new RegionNode(3);
3977 _gvn.set_type(region, Type::CONTROL);
3978 lengthx = new PhiNode(region, TypeLong::LONG);
3979 _gvn.set_type(lengthx, TypeLong::LONG);
3980
3981 // Range check passed. Use ConvI2L node with narrow type.
3982 Node* passed = IfFalse(iff);
3983 region->init_req(1, passed);
3984 // Make I2L conversion control dependent to prevent it from
3985 // floating above the range check during loop optimizations.
3986 lengthx->init_req(1, C->constrained_convI2L(&_gvn, length, tlcon, passed));
3987
3988 // Range check failed. Use ConvI2L with wide type because length may be invalid.
3989 region->init_req(2, IfTrue(iff));
3990 lengthx->init_req(2, ConvI2X(length));
3991
3992 set_control(region);
3993 record_for_igvn(region);
3994 record_for_igvn(lengthx);
3995 }
3996 }
3997 #endif
3998
3999 // Combine header size and body size for the array copy part, then align (if
4000 // necessary) for the allocation part. This computation cannot overflow,
4001 // because it is used only in two places, one where the length is sharply
4002 // limited, and the other after a successful allocation.
4003 Node* abody = lengthx;
4004 if (elem_shift != nullptr) {
4005 abody = _gvn.transform(new LShiftXNode(lengthx, elem_shift));
4006 }
4007 Node* non_rounded_size = _gvn.transform(new AddXNode(headerx, abody));
4008
4009 if (return_size_val != nullptr) {
4010 // This is the size
4011 (*return_size_val) = non_rounded_size;
4012 }
4013
4014 Node* size = non_rounded_size;
4015 if (round_mask != 0) {
4016 Node* mask1 = MakeConX(round_mask);
4017 size = _gvn.transform(new AddXNode(size, mask1));
4018 Node* mask2 = MakeConX(~round_mask);
4019 size = _gvn.transform(new AndXNode(size, mask2));
4020 }
4021 // else if round_mask == 0, the size computation is self-rounding
4022
4023 // Now generate allocation code
4024
4025 // The entire memory state is needed for slow path of the allocation
4026 // since GC and deoptimization can happened.
4027 Node *mem = reset_memory();
4028 set_all_memory(mem); // Create new memory state
4029
4030 if (initial_slow_test->is_Bool()) {
4031 // Hide it behind a CMoveI, or else PhaseIdealLoop::split_up will get sick.
4032 initial_slow_test = initial_slow_test->as_Bool()->as_int_value(&_gvn);
4033 }
4034
4035 const TypeOopPtr* ary_type = _gvn.type(klass_node)->is_klassptr()->as_instance_type();
4036 Node* valid_length_test = _gvn.intcon(1);
4037 if (ary_type->isa_aryptr()) {
4038 BasicType bt = ary_type->isa_aryptr()->elem()->array_element_basic_type();
4039 jint max = TypeAryPtr::max_array_length(bt);
4040 Node* valid_length_cmp = _gvn.transform(new CmpUNode(length, intcon(max)));
4041 valid_length_test = _gvn.transform(new BoolNode(valid_length_cmp, BoolTest::le));
4042 }
4043
4044 // Create the AllocateArrayNode and its result projections
4045 AllocateArrayNode* alloc
4046 = new AllocateArrayNode(C, AllocateArrayNode::alloc_type(TypeInt::INT),
4047 control(), mem, i_o(),
4048 size, klass_node,
4049 initial_slow_test,
4050 length, valid_length_test);
4051
4052 // Cast to correct type. Note that the klass_node may be constant or not,
4053 // and in the latter case the actual array type will be inexact also.
4054 // (This happens via a non-constant argument to inline_native_newArray.)
4055 // In any case, the value of klass_node provides the desired array type.
4056 const TypeInt* length_type = _gvn.find_int_type(length);
4057 if (ary_type->isa_aryptr() && length_type != nullptr) {
4058 // Try to get a better type than POS for the size
4059 ary_type = ary_type->is_aryptr()->cast_to_size(length_type);
4060 }
4061
4062 Node* javaoop = set_output_for_allocation(alloc, ary_type, deoptimize_on_exception);
4063
4064 array_ideal_length(alloc, ary_type, true);
4065 return javaoop;
4066 }
4067
4068 // The following "Ideal_foo" functions are placed here because they recognize
4069 // the graph shapes created by the functions immediately above.
4070
4071 //---------------------------Ideal_allocation----------------------------------
4072 // Given an oop pointer or raw pointer, see if it feeds from an AllocateNode.
4073 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr) {
4074 if (ptr == nullptr) { // reduce dumb test in callers
4075 return nullptr;
4076 }
4077
4078 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
4079 ptr = bs->step_over_gc_barrier(ptr);
4080
4081 if (ptr->is_CheckCastPP()) { // strip only one raw-to-oop cast
4082 ptr = ptr->in(1);
4083 if (ptr == nullptr) return nullptr;
4084 }
4085 // Return null for allocations with several casts:
4086 // j.l.reflect.Array.newInstance(jobject, jint)
4087 // Object.clone()
4088 // to keep more precise type from last cast.
4089 if (ptr->is_Proj()) {
4090 Node* allo = ptr->in(0);
4091 if (allo != nullptr && allo->is_Allocate()) {
4092 return allo->as_Allocate();
4093 }
4094 }
4095 // Report failure to match.
4096 return nullptr;
4097 }
4098
4099 // Fancy version which also strips off an offset (and reports it to caller).
4100 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseValues* phase,
4101 intptr_t& offset) {
4102 Node* base = AddPNode::Ideal_base_and_offset(ptr, phase, offset);
4103 if (base == nullptr) return nullptr;
4104 return Ideal_allocation(base);
4105 }
4106
4107 // Trace Initialize <- Proj[Parm] <- Allocate
4108 AllocateNode* InitializeNode::allocation() {
4109 Node* rawoop = in(InitializeNode::RawAddress);
4110 if (rawoop->is_Proj()) {
4111 Node* alloc = rawoop->in(0);
4112 if (alloc->is_Allocate()) {
4113 return alloc->as_Allocate();
4114 }
4115 }
4116 return nullptr;
4117 }
4118
4119 // Trace Allocate -> Proj[Parm] -> Initialize
4120 InitializeNode* AllocateNode::initialization() {
4121 ProjNode* rawoop = proj_out_or_null(AllocateNode::RawAddress);
4122 if (rawoop == nullptr) return nullptr;
4123 for (DUIterator_Fast imax, i = rawoop->fast_outs(imax); i < imax; i++) {
4124 Node* init = rawoop->fast_out(i);
4125 if (init->is_Initialize()) {
4126 assert(init->as_Initialize()->allocation() == this, "2-way link");
4127 return init->as_Initialize();
4128 }
4129 }
4130 return nullptr;
4131 }
4132
4133 // Add a Parse Predicate with an uncommon trap on the failing/false path. Normal control will continue on the true path.
4134 void GraphKit::add_parse_predicate(Deoptimization::DeoptReason reason, const int nargs) {
4135 // Too many traps seen?
4136 if (too_many_traps(reason)) {
4137 #ifdef ASSERT
4138 if (TraceLoopPredicate) {
4139 int tc = C->trap_count(reason);
4140 tty->print("too many traps=%s tcount=%d in ",
4141 Deoptimization::trap_reason_name(reason), tc);
4142 method()->print(); // which method has too many predicate traps
4143 tty->cr();
4144 }
4145 #endif
4146 // We cannot afford to take more traps here,
4147 // do not generate Parse Predicate.
4148 return;
4149 }
4150
4151 ParsePredicateNode* parse_predicate = new ParsePredicateNode(control(), reason, &_gvn);
4152 _gvn.set_type(parse_predicate, parse_predicate->Value(&_gvn));
4153 Node* if_false = _gvn.transform(new IfFalseNode(parse_predicate));
4154 {
4155 PreserveJVMState pjvms(this);
4156 set_control(if_false);
4157 inc_sp(nargs);
4158 uncommon_trap(reason, Deoptimization::Action_maybe_recompile);
4159 }
4160 Node* if_true = _gvn.transform(new IfTrueNode(parse_predicate));
4161 set_control(if_true);
4162 }
4163
4164 // Add Parse Predicates which serve as placeholders to create new Runtime Predicates above them. All
4165 // Runtime Predicates inside a Runtime Predicate block share the same uncommon trap as the Parse Predicate.
4166 void GraphKit::add_parse_predicates(int nargs) {
4167 if (ShortRunningLongLoop) {
4168 // Will narrow the limit down with a cast node. Predicates added later may depend on the cast so should be last when
4169 // walking up from the loop.
4170 add_parse_predicate(Deoptimization::Reason_short_running_long_loop, nargs);
4171 }
4172 if (UseLoopPredicate) {
4173 add_parse_predicate(Deoptimization::Reason_predicate, nargs);
4174 if (UseProfiledLoopPredicate) {
4175 add_parse_predicate(Deoptimization::Reason_profile_predicate, nargs);
4176 }
4177 }
4178 if (UseAutoVectorizationPredicate) {
4179 add_parse_predicate(Deoptimization::Reason_auto_vectorization_check, nargs);
4180 }
4181 // Loop Limit Check Predicate should be near the loop.
4182 add_parse_predicate(Deoptimization::Reason_loop_limit_check, nargs);
4183 }
4184
4185 void GraphKit::sync_kit(IdealKit& ideal) {
4186 set_all_memory(ideal.merged_memory());
4187 set_i_o(ideal.i_o());
4188 set_control(ideal.ctrl());
4189 }
4190
4191 void GraphKit::final_sync(IdealKit& ideal) {
4192 // Final sync IdealKit and graphKit.
4193 sync_kit(ideal);
4194 }
4195
4196 Node* GraphKit::load_String_length(Node* str, bool set_ctrl) {
4197 Node* len = load_array_length(load_String_value(str, set_ctrl));
4198 Node* coder = load_String_coder(str, set_ctrl);
4199 // Divide length by 2 if coder is UTF16
4200 return _gvn.transform(new RShiftINode(len, coder));
4201 }
4202
4203 Node* GraphKit::load_String_value(Node* str, bool set_ctrl) {
4204 int value_offset = java_lang_String::value_offset();
4205 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4206 false, nullptr, 0);
4207 const TypePtr* value_field_type = string_type->add_offset(value_offset);
4208 const TypeAryPtr* value_type = TypeAryPtr::make(TypePtr::NotNull,
4209 TypeAry::make(TypeInt::BYTE, TypeInt::POS),
4210 ciTypeArrayKlass::make(T_BYTE), true, 0);
4211 Node* p = basic_plus_adr(str, str, value_offset);
4212 Node* load = access_load_at(str, p, value_field_type, value_type, T_OBJECT,
4213 IN_HEAP | (set_ctrl ? C2_CONTROL_DEPENDENT_LOAD : 0) | MO_UNORDERED);
4214 return load;
4215 }
4216
4217 Node* GraphKit::load_String_coder(Node* str, bool set_ctrl) {
4218 if (!CompactStrings) {
4219 return intcon(java_lang_String::CODER_UTF16);
4220 }
4221 int coder_offset = java_lang_String::coder_offset();
4222 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4223 false, nullptr, 0);
4224 const TypePtr* coder_field_type = string_type->add_offset(coder_offset);
4225
4226 Node* p = basic_plus_adr(str, str, coder_offset);
4227 Node* load = access_load_at(str, p, coder_field_type, TypeInt::BYTE, T_BYTE,
4228 IN_HEAP | (set_ctrl ? C2_CONTROL_DEPENDENT_LOAD : 0) | MO_UNORDERED);
4229 return load;
4230 }
4231
4232 void GraphKit::store_String_value(Node* str, Node* value) {
4233 int value_offset = java_lang_String::value_offset();
4234 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4235 false, nullptr, 0);
4236 const TypePtr* value_field_type = string_type->add_offset(value_offset);
4237
4238 access_store_at(str, basic_plus_adr(str, value_offset), value_field_type,
4239 value, TypeAryPtr::BYTES, T_OBJECT, IN_HEAP | MO_UNORDERED);
4240 }
4241
4242 void GraphKit::store_String_coder(Node* str, Node* value) {
4243 int coder_offset = java_lang_String::coder_offset();
4244 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4245 false, nullptr, 0);
4246 const TypePtr* coder_field_type = string_type->add_offset(coder_offset);
4247
4248 access_store_at(str, basic_plus_adr(str, coder_offset), coder_field_type,
4249 value, TypeInt::BYTE, T_BYTE, IN_HEAP | MO_UNORDERED);
4250 }
4251
4252 // Capture src and dst memory state with a MergeMemNode
4253 Node* GraphKit::capture_memory(const TypePtr* src_type, const TypePtr* dst_type) {
4254 if (src_type == dst_type) {
4255 // Types are equal, we don't need a MergeMemNode
4256 return memory(src_type);
4257 }
4258 MergeMemNode* merge = MergeMemNode::make(map()->memory());
4259 record_for_igvn(merge); // fold it up later, if possible
4260 int src_idx = C->get_alias_index(src_type);
4261 int dst_idx = C->get_alias_index(dst_type);
4262 merge->set_memory_at(src_idx, memory(src_idx));
4263 merge->set_memory_at(dst_idx, memory(dst_idx));
4264 return merge;
4265 }
4266
4267 Node* GraphKit::compress_string(Node* src, const TypeAryPtr* src_type, Node* dst, Node* count) {
4268 assert(Matcher::match_rule_supported(Op_StrCompressedCopy), "Intrinsic not supported");
4269 assert(src_type == TypeAryPtr::BYTES || src_type == TypeAryPtr::CHARS, "invalid source type");
4270 // If input and output memory types differ, capture both states to preserve
4271 // the dependency between preceding and subsequent loads/stores.
4272 // For example, the following program:
4273 // StoreB
4274 // compress_string
4275 // LoadB
4276 // has this memory graph (use->def):
4277 // LoadB -> compress_string -> CharMem
4278 // ... -> StoreB -> ByteMem
4279 // The intrinsic hides the dependency between LoadB and StoreB, causing
4280 // the load to read from memory not containing the result of the StoreB.
4281 // The correct memory graph should look like this:
4282 // LoadB -> compress_string -> MergeMem(CharMem, StoreB(ByteMem))
4283 Node* mem = capture_memory(src_type, TypeAryPtr::BYTES);
4284 StrCompressedCopyNode* str = new StrCompressedCopyNode(control(), mem, src, dst, count);
4285 Node* res_mem = _gvn.transform(new SCMemProjNode(_gvn.transform(str)));
4286 set_memory(res_mem, TypeAryPtr::BYTES);
4287 return str;
4288 }
4289
4290 void GraphKit::inflate_string(Node* src, Node* dst, const TypeAryPtr* dst_type, Node* count) {
4291 assert(Matcher::match_rule_supported(Op_StrInflatedCopy), "Intrinsic not supported");
4292 assert(dst_type == TypeAryPtr::BYTES || dst_type == TypeAryPtr::CHARS, "invalid dest type");
4293 // Capture src and dst memory (see comment in 'compress_string').
4294 Node* mem = capture_memory(TypeAryPtr::BYTES, dst_type);
4295 StrInflatedCopyNode* str = new StrInflatedCopyNode(control(), mem, src, dst, count);
4296 set_memory(_gvn.transform(str), dst_type);
4297 }
4298
4299 void GraphKit::inflate_string_slow(Node* src, Node* dst, Node* start, Node* count) {
4300 /**
4301 * int i_char = start;
4302 * for (int i_byte = 0; i_byte < count; i_byte++) {
4303 * dst[i_char++] = (char)(src[i_byte] & 0xff);
4304 * }
4305 */
4306 add_parse_predicates();
4307 C->set_has_loops(true);
4308
4309 RegionNode* head = new RegionNode(3);
4310 head->init_req(1, control());
4311 gvn().set_type(head, Type::CONTROL);
4312 record_for_igvn(head);
4313
4314 Node* i_byte = new PhiNode(head, TypeInt::INT);
4315 i_byte->init_req(1, intcon(0));
4316 gvn().set_type(i_byte, TypeInt::INT);
4317 record_for_igvn(i_byte);
4318
4319 Node* i_char = new PhiNode(head, TypeInt::INT);
4320 i_char->init_req(1, start);
4321 gvn().set_type(i_char, TypeInt::INT);
4322 record_for_igvn(i_char);
4323
4324 Node* mem = PhiNode::make(head, memory(TypeAryPtr::BYTES), Type::MEMORY, TypeAryPtr::BYTES);
4325 gvn().set_type(mem, Type::MEMORY);
4326 record_for_igvn(mem);
4327 set_control(head);
4328 set_memory(mem, TypeAryPtr::BYTES);
4329 Node* ch = load_array_element(src, i_byte, TypeAryPtr::BYTES, /* set_ctrl */ true);
4330 Node* st = store_to_memory(control(), array_element_address(dst, i_char, T_BYTE),
4331 AndI(ch, intcon(0xff)), T_CHAR, MemNode::unordered, false,
4332 false, true /* mismatched */);
4333
4334 IfNode* iff = create_and_map_if(head, Bool(CmpI(i_byte, count), BoolTest::lt), PROB_FAIR, COUNT_UNKNOWN);
4335 head->init_req(2, IfTrue(iff));
4336 mem->init_req(2, st);
4337 i_byte->init_req(2, AddI(i_byte, intcon(1)));
4338 i_char->init_req(2, AddI(i_char, intcon(2)));
4339
4340 set_control(IfFalse(iff));
4341 set_memory(st, TypeAryPtr::BYTES);
4342 }
4343
4344 Node* GraphKit::make_constant_from_field(ciField* field, Node* obj) {
4345 if (!field->is_constant()) {
4346 return nullptr; // Field not marked as constant.
4347 }
4348 ciInstance* holder = nullptr;
4349 if (!field->is_static()) {
4350 ciObject* const_oop = obj->bottom_type()->is_oopptr()->const_oop();
4351 if (const_oop != nullptr && const_oop->is_instance()) {
4352 holder = const_oop->as_instance();
4353 }
4354 }
4355 const Type* con_type = Type::make_constant_from_field(field, holder, field->layout_type(),
4356 /*is_unsigned_load=*/false);
4357 if (con_type != nullptr) {
4358 return makecon(con_type);
4359 }
4360 return nullptr;
4361 }
4362
4363 Node* GraphKit::maybe_narrow_object_type(Node* obj, ciKlass* type) {
4364 const TypeOopPtr* obj_type = obj->bottom_type()->isa_oopptr();
4365 const TypeOopPtr* sig_type = TypeOopPtr::make_from_klass(type);
4366 if (obj_type != nullptr && sig_type->is_loaded() && !obj_type->higher_equal(sig_type)) {
4367 const Type* narrow_obj_type = obj_type->filter_speculative(sig_type); // keep speculative part
4368 Node* casted_obj = gvn().transform(new CheckCastPPNode(control(), obj, narrow_obj_type));
4369 return casted_obj;
4370 }
4371 return obj;
4372 }