1 /*
2 * Copyright (c) 2001, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "compiler/compileLog.hpp"
27 #include "gc/g1/g1SATBCardTableModRefBS.hpp"
28 #include "gc/g1/heapRegion.hpp"
29 #include "gc/shared/barrierSet.hpp"
30 #include "gc/shared/cardTableModRefBS.hpp"
31 #include "gc/shared/collectedHeap.hpp"
32 #include "memory/resourceArea.hpp"
33 #include "opto/addnode.hpp"
34 #include "opto/castnode.hpp"
35 #include "opto/convertnode.hpp"
36 #include "opto/graphKit.hpp"
37 #include "opto/idealKit.hpp"
38 #include "opto/intrinsicnode.hpp"
39 #include "opto/locknode.hpp"
40 #include "opto/machnode.hpp"
41 #include "opto/opaquenode.hpp"
42 #include "opto/parse.hpp"
43 #include "opto/rootnode.hpp"
44 #include "opto/runtime.hpp"
45 #include "runtime/deoptimization.hpp"
46 #include "runtime/sharedRuntime.hpp"
47
48 //----------------------------GraphKit-----------------------------------------
49 // Main utility constructor.
50 GraphKit::GraphKit(JVMState* jvms)
51 : Phase(Phase::Parser),
52 _env(C->env()),
53 _gvn(*C->initial_gvn())
54 {
55 _exceptions = jvms->map()->next_exception();
56 if (_exceptions != NULL) jvms->map()->set_next_exception(NULL);
57 set_jvms(jvms);
58 }
59
60 // Private constructor for parser.
61 GraphKit::GraphKit()
62 : Phase(Phase::Parser),
63 _env(C->env()),
64 _gvn(*C->initial_gvn())
65 {
66 _exceptions = NULL;
67 set_map(NULL);
68 debug_only(_sp = -99);
69 debug_only(set_bci(-99));
70 }
71
72
73
74 //---------------------------clean_stack---------------------------------------
75 // Clear away rubbish from the stack area of the JVM state.
76 // This destroys any arguments that may be waiting on the stack.
77 void GraphKit::clean_stack(int from_sp) {
78 SafePointNode* map = this->map();
79 JVMState* jvms = this->jvms();
80 int stk_size = jvms->stk_size();
81 int stkoff = jvms->stkoff();
82 Node* top = this->top();
83 for (int i = from_sp; i < stk_size; i++) {
84 if (map->in(stkoff + i) != top) {
85 map->set_req(stkoff + i, top);
86 }
87 }
88 }
89
90
91 //--------------------------------sync_jvms-----------------------------------
92 // Make sure our current jvms agrees with our parse state.
93 JVMState* GraphKit::sync_jvms() const {
94 JVMState* jvms = this->jvms();
95 jvms->set_bci(bci()); // Record the new bci in the JVMState
96 jvms->set_sp(sp()); // Record the new sp in the JVMState
97 assert(jvms_in_sync(), "jvms is now in sync");
98 return jvms;
99 }
100
101 //--------------------------------sync_jvms_for_reexecute---------------------
102 // Make sure our current jvms agrees with our parse state. This version
103 // uses the reexecute_sp for reexecuting bytecodes.
104 JVMState* GraphKit::sync_jvms_for_reexecute() {
105 JVMState* jvms = this->jvms();
106 jvms->set_bci(bci()); // Record the new bci in the JVMState
107 jvms->set_sp(reexecute_sp()); // Record the new sp in the JVMState
108 return jvms;
109 }
110
111 #ifdef ASSERT
112 bool GraphKit::jvms_in_sync() const {
113 Parse* parse = is_Parse();
114 if (parse == NULL) {
115 if (bci() != jvms()->bci()) return false;
116 if (sp() != (int)jvms()->sp()) return false;
117 return true;
118 }
119 if (jvms()->method() != parse->method()) return false;
120 if (jvms()->bci() != parse->bci()) return false;
121 int jvms_sp = jvms()->sp();
122 if (jvms_sp != parse->sp()) return false;
123 int jvms_depth = jvms()->depth();
124 if (jvms_depth != parse->depth()) return false;
125 return true;
126 }
127
128 // Local helper checks for special internal merge points
129 // used to accumulate and merge exception states.
130 // They are marked by the region's in(0) edge being the map itself.
131 // Such merge points must never "escape" into the parser at large,
132 // until they have been handed to gvn.transform.
133 static bool is_hidden_merge(Node* reg) {
134 if (reg == NULL) return false;
135 if (reg->is_Phi()) {
136 reg = reg->in(0);
137 if (reg == NULL) return false;
138 }
139 return reg->is_Region() && reg->in(0) != NULL && reg->in(0)->is_Root();
140 }
141
142 void GraphKit::verify_map() const {
143 if (map() == NULL) return; // null map is OK
144 assert(map()->req() <= jvms()->endoff(), "no extra garbage on map");
145 assert(!map()->has_exceptions(), "call add_exception_states_from 1st");
146 assert(!is_hidden_merge(control()), "call use_exception_state, not set_map");
147 }
148
149 void GraphKit::verify_exception_state(SafePointNode* ex_map) {
150 assert(ex_map->next_exception() == NULL, "not already part of a chain");
151 assert(has_saved_ex_oop(ex_map), "every exception state has an ex_oop");
152 }
153 #endif
154
155 //---------------------------stop_and_kill_map---------------------------------
156 // Set _map to NULL, signalling a stop to further bytecode execution.
157 // First smash the current map's control to a constant, to mark it dead.
158 void GraphKit::stop_and_kill_map() {
159 SafePointNode* dead_map = stop();
160 if (dead_map != NULL) {
161 dead_map->disconnect_inputs(NULL, C); // Mark the map as killed.
162 assert(dead_map->is_killed(), "must be so marked");
163 }
164 }
165
166
167 //--------------------------------stopped--------------------------------------
168 // Tell if _map is NULL, or control is top.
169 bool GraphKit::stopped() {
170 if (map() == NULL) return true;
171 else if (control() == top()) return true;
172 else return false;
173 }
174
175
176 //-----------------------------has_ex_handler----------------------------------
177 // Tell if this method or any caller method has exception handlers.
178 bool GraphKit::has_ex_handler() {
179 for (JVMState* jvmsp = jvms(); jvmsp != NULL; jvmsp = jvmsp->caller()) {
180 if (jvmsp->has_method() && jvmsp->method()->has_exception_handlers()) {
181 return true;
182 }
183 }
184 return false;
185 }
186
187 //------------------------------save_ex_oop------------------------------------
188 // Save an exception without blowing stack contents or other JVM state.
189 void GraphKit::set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop) {
190 assert(!has_saved_ex_oop(ex_map), "clear ex-oop before setting again");
191 ex_map->add_req(ex_oop);
192 debug_only(verify_exception_state(ex_map));
193 }
194
195 inline static Node* common_saved_ex_oop(SafePointNode* ex_map, bool clear_it) {
196 assert(GraphKit::has_saved_ex_oop(ex_map), "ex_oop must be there");
197 Node* ex_oop = ex_map->in(ex_map->req()-1);
198 if (clear_it) ex_map->del_req(ex_map->req()-1);
199 return ex_oop;
200 }
201
202 //-----------------------------saved_ex_oop------------------------------------
203 // Recover a saved exception from its map.
204 Node* GraphKit::saved_ex_oop(SafePointNode* ex_map) {
205 return common_saved_ex_oop(ex_map, false);
206 }
207
208 //--------------------------clear_saved_ex_oop---------------------------------
209 // Erase a previously saved exception from its map.
210 Node* GraphKit::clear_saved_ex_oop(SafePointNode* ex_map) {
211 return common_saved_ex_oop(ex_map, true);
212 }
213
214 #ifdef ASSERT
215 //---------------------------has_saved_ex_oop----------------------------------
216 // Erase a previously saved exception from its map.
217 bool GraphKit::has_saved_ex_oop(SafePointNode* ex_map) {
218 return ex_map->req() == ex_map->jvms()->endoff()+1;
219 }
220 #endif
221
222 //-------------------------make_exception_state--------------------------------
223 // Turn the current JVM state into an exception state, appending the ex_oop.
224 SafePointNode* GraphKit::make_exception_state(Node* ex_oop) {
225 sync_jvms();
226 SafePointNode* ex_map = stop(); // do not manipulate this map any more
227 set_saved_ex_oop(ex_map, ex_oop);
228 return ex_map;
229 }
230
231
232 //--------------------------add_exception_state--------------------------------
233 // Add an exception to my list of exceptions.
234 void GraphKit::add_exception_state(SafePointNode* ex_map) {
235 if (ex_map == NULL || ex_map->control() == top()) {
236 return;
237 }
238 #ifdef ASSERT
239 verify_exception_state(ex_map);
240 if (has_exceptions()) {
241 assert(ex_map->jvms()->same_calls_as(_exceptions->jvms()), "all collected exceptions must come from the same place");
242 }
243 #endif
244
245 // If there is already an exception of exactly this type, merge with it.
246 // In particular, null-checks and other low-level exceptions common up here.
247 Node* ex_oop = saved_ex_oop(ex_map);
248 const Type* ex_type = _gvn.type(ex_oop);
249 if (ex_oop == top()) {
250 // No action needed.
251 return;
252 }
253 assert(ex_type->isa_instptr(), "exception must be an instance");
254 for (SafePointNode* e2 = _exceptions; e2 != NULL; e2 = e2->next_exception()) {
255 const Type* ex_type2 = _gvn.type(saved_ex_oop(e2));
256 // We check sp also because call bytecodes can generate exceptions
257 // both before and after arguments are popped!
258 if (ex_type2 == ex_type
259 && e2->_jvms->sp() == ex_map->_jvms->sp()) {
260 combine_exception_states(ex_map, e2);
261 return;
262 }
263 }
264
265 // No pre-existing exception of the same type. Chain it on the list.
266 push_exception_state(ex_map);
267 }
268
269 //-----------------------add_exception_states_from-----------------------------
270 void GraphKit::add_exception_states_from(JVMState* jvms) {
271 SafePointNode* ex_map = jvms->map()->next_exception();
272 if (ex_map != NULL) {
273 jvms->map()->set_next_exception(NULL);
274 for (SafePointNode* next_map; ex_map != NULL; ex_map = next_map) {
275 next_map = ex_map->next_exception();
276 ex_map->set_next_exception(NULL);
277 add_exception_state(ex_map);
278 }
279 }
280 }
281
282 //-----------------------transfer_exceptions_into_jvms-------------------------
283 JVMState* GraphKit::transfer_exceptions_into_jvms() {
284 if (map() == NULL) {
285 // We need a JVMS to carry the exceptions, but the map has gone away.
286 // Create a scratch JVMS, cloned from any of the exception states...
287 if (has_exceptions()) {
288 _map = _exceptions;
289 _map = clone_map();
290 _map->set_next_exception(NULL);
291 clear_saved_ex_oop(_map);
292 debug_only(verify_map());
293 } else {
294 // ...or created from scratch
295 JVMState* jvms = new (C) JVMState(_method, NULL);
296 jvms->set_bci(_bci);
297 jvms->set_sp(_sp);
298 jvms->set_map(new SafePointNode(TypeFunc::Parms, jvms));
299 set_jvms(jvms);
300 for (uint i = 0; i < map()->req(); i++) map()->init_req(i, top());
301 set_all_memory(top());
302 while (map()->req() < jvms->endoff()) map()->add_req(top());
303 }
304 // (This is a kludge, in case you didn't notice.)
305 set_control(top());
306 }
307 JVMState* jvms = sync_jvms();
308 assert(!jvms->map()->has_exceptions(), "no exceptions on this map yet");
309 jvms->map()->set_next_exception(_exceptions);
310 _exceptions = NULL; // done with this set of exceptions
311 return jvms;
312 }
313
314 static inline void add_n_reqs(Node* dstphi, Node* srcphi) {
315 assert(is_hidden_merge(dstphi), "must be a special merge node");
316 assert(is_hidden_merge(srcphi), "must be a special merge node");
317 uint limit = srcphi->req();
318 for (uint i = PhiNode::Input; i < limit; i++) {
319 dstphi->add_req(srcphi->in(i));
320 }
321 }
322 static inline void add_one_req(Node* dstphi, Node* src) {
323 assert(is_hidden_merge(dstphi), "must be a special merge node");
324 assert(!is_hidden_merge(src), "must not be a special merge node");
325 dstphi->add_req(src);
326 }
327
328 //-----------------------combine_exception_states------------------------------
329 // This helper function combines exception states by building phis on a
330 // specially marked state-merging region. These regions and phis are
331 // untransformed, and can build up gradually. The region is marked by
332 // having a control input of its exception map, rather than NULL. Such
333 // regions do not appear except in this function, and in use_exception_state.
334 void GraphKit::combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map) {
335 if (failing()) return; // dying anyway...
336 JVMState* ex_jvms = ex_map->_jvms;
337 assert(ex_jvms->same_calls_as(phi_map->_jvms), "consistent call chains");
338 assert(ex_jvms->stkoff() == phi_map->_jvms->stkoff(), "matching locals");
339 assert(ex_jvms->sp() == phi_map->_jvms->sp(), "matching stack sizes");
340 assert(ex_jvms->monoff() == phi_map->_jvms->monoff(), "matching JVMS");
341 assert(ex_jvms->scloff() == phi_map->_jvms->scloff(), "matching scalar replaced objects");
342 assert(ex_map->req() == phi_map->req(), "matching maps");
343 uint tos = ex_jvms->stkoff() + ex_jvms->sp();
344 Node* hidden_merge_mark = root();
345 Node* region = phi_map->control();
346 MergeMemNode* phi_mem = phi_map->merged_memory();
347 MergeMemNode* ex_mem = ex_map->merged_memory();
348 if (region->in(0) != hidden_merge_mark) {
349 // The control input is not (yet) a specially-marked region in phi_map.
350 // Make it so, and build some phis.
351 region = new RegionNode(2);
352 _gvn.set_type(region, Type::CONTROL);
353 region->set_req(0, hidden_merge_mark); // marks an internal ex-state
354 region->init_req(1, phi_map->control());
355 phi_map->set_control(region);
356 Node* io_phi = PhiNode::make(region, phi_map->i_o(), Type::ABIO);
357 record_for_igvn(io_phi);
358 _gvn.set_type(io_phi, Type::ABIO);
359 phi_map->set_i_o(io_phi);
360 for (MergeMemStream mms(phi_mem); mms.next_non_empty(); ) {
361 Node* m = mms.memory();
362 Node* m_phi = PhiNode::make(region, m, Type::MEMORY, mms.adr_type(C));
363 record_for_igvn(m_phi);
364 _gvn.set_type(m_phi, Type::MEMORY);
365 mms.set_memory(m_phi);
366 }
367 }
368
369 // Either or both of phi_map and ex_map might already be converted into phis.
370 Node* ex_control = ex_map->control();
371 // if there is special marking on ex_map also, we add multiple edges from src
372 bool add_multiple = (ex_control->in(0) == hidden_merge_mark);
373 // how wide was the destination phi_map, originally?
374 uint orig_width = region->req();
375
376 if (add_multiple) {
377 add_n_reqs(region, ex_control);
378 add_n_reqs(phi_map->i_o(), ex_map->i_o());
379 } else {
380 // ex_map has no merges, so we just add single edges everywhere
381 add_one_req(region, ex_control);
382 add_one_req(phi_map->i_o(), ex_map->i_o());
383 }
384 for (MergeMemStream mms(phi_mem, ex_mem); mms.next_non_empty2(); ) {
385 if (mms.is_empty()) {
386 // get a copy of the base memory, and patch some inputs into it
387 const TypePtr* adr_type = mms.adr_type(C);
388 Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
389 assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
390 mms.set_memory(phi);
391 // Prepare to append interesting stuff onto the newly sliced phi:
392 while (phi->req() > orig_width) phi->del_req(phi->req()-1);
393 }
394 // Append stuff from ex_map:
395 if (add_multiple) {
396 add_n_reqs(mms.memory(), mms.memory2());
397 } else {
398 add_one_req(mms.memory(), mms.memory2());
399 }
400 }
401 uint limit = ex_map->req();
402 for (uint i = TypeFunc::Parms; i < limit; i++) {
403 // Skip everything in the JVMS after tos. (The ex_oop follows.)
404 if (i == tos) i = ex_jvms->monoff();
405 Node* src = ex_map->in(i);
406 Node* dst = phi_map->in(i);
407 if (src != dst) {
408 PhiNode* phi;
409 if (dst->in(0) != region) {
410 dst = phi = PhiNode::make(region, dst, _gvn.type(dst));
411 record_for_igvn(phi);
412 _gvn.set_type(phi, phi->type());
413 phi_map->set_req(i, dst);
414 // Prepare to append interesting stuff onto the new phi:
415 while (dst->req() > orig_width) dst->del_req(dst->req()-1);
416 } else {
417 assert(dst->is_Phi(), "nobody else uses a hidden region");
418 phi = dst->as_Phi();
419 }
420 if (add_multiple && src->in(0) == ex_control) {
421 // Both are phis.
422 add_n_reqs(dst, src);
423 } else {
424 while (dst->req() < region->req()) add_one_req(dst, src);
425 }
426 const Type* srctype = _gvn.type(src);
427 if (phi->type() != srctype) {
428 const Type* dsttype = phi->type()->meet_speculative(srctype);
429 if (phi->type() != dsttype) {
430 phi->set_type(dsttype);
431 _gvn.set_type(phi, dsttype);
432 }
433 }
434 }
435 }
436 phi_map->merge_replaced_nodes_with(ex_map);
437 }
438
439 //--------------------------use_exception_state--------------------------------
440 Node* GraphKit::use_exception_state(SafePointNode* phi_map) {
441 if (failing()) { stop(); return top(); }
442 Node* region = phi_map->control();
443 Node* hidden_merge_mark = root();
444 assert(phi_map->jvms()->map() == phi_map, "sanity: 1-1 relation");
445 Node* ex_oop = clear_saved_ex_oop(phi_map);
446 if (region->in(0) == hidden_merge_mark) {
447 // Special marking for internal ex-states. Process the phis now.
448 region->set_req(0, region); // now it's an ordinary region
449 set_jvms(phi_map->jvms()); // ...so now we can use it as a map
450 // Note: Setting the jvms also sets the bci and sp.
451 set_control(_gvn.transform(region));
452 uint tos = jvms()->stkoff() + sp();
453 for (uint i = 1; i < tos; i++) {
454 Node* x = phi_map->in(i);
455 if (x->in(0) == region) {
456 assert(x->is_Phi(), "expected a special phi");
457 phi_map->set_req(i, _gvn.transform(x));
458 }
459 }
460 for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
461 Node* x = mms.memory();
462 if (x->in(0) == region) {
463 assert(x->is_Phi(), "nobody else uses a hidden region");
464 mms.set_memory(_gvn.transform(x));
465 }
466 }
467 if (ex_oop->in(0) == region) {
468 assert(ex_oop->is_Phi(), "expected a special phi");
469 ex_oop = _gvn.transform(ex_oop);
470 }
471 } else {
472 set_jvms(phi_map->jvms());
473 }
474
475 assert(!is_hidden_merge(phi_map->control()), "hidden ex. states cleared");
476 assert(!is_hidden_merge(phi_map->i_o()), "hidden ex. states cleared");
477 return ex_oop;
478 }
479
480 //---------------------------------java_bc-------------------------------------
481 Bytecodes::Code GraphKit::java_bc() const {
482 ciMethod* method = this->method();
483 int bci = this->bci();
484 if (method != NULL && bci != InvocationEntryBci)
485 return method->java_code_at_bci(bci);
486 else
487 return Bytecodes::_illegal;
488 }
489
490 void GraphKit::uncommon_trap_if_should_post_on_exceptions(Deoptimization::DeoptReason reason,
491 bool must_throw) {
492 // if the exception capability is set, then we will generate code
493 // to check the JavaThread.should_post_on_exceptions flag to see
494 // if we actually need to report exception events (for this
495 // thread). If we don't need to report exception events, we will
496 // take the normal fast path provided by add_exception_events. If
497 // exception event reporting is enabled for this thread, we will
498 // take the uncommon_trap in the BuildCutout below.
499
500 // first must access the should_post_on_exceptions_flag in this thread's JavaThread
501 Node* jthread = _gvn.transform(new ThreadLocalNode());
502 Node* adr = basic_plus_adr(top(), jthread, in_bytes(JavaThread::should_post_on_exceptions_flag_offset()));
503 Node* should_post_flag = make_load(control(), adr, TypeInt::INT, T_INT, Compile::AliasIdxRaw, MemNode::unordered);
504
505 // Test the should_post_on_exceptions_flag vs. 0
506 Node* chk = _gvn.transform( new CmpINode(should_post_flag, intcon(0)) );
507 Node* tst = _gvn.transform( new BoolNode(chk, BoolTest::eq) );
508
509 // Branch to slow_path if should_post_on_exceptions_flag was true
510 { BuildCutout unless(this, tst, PROB_MAX);
511 // Do not try anything fancy if we're notifying the VM on every throw.
512 // Cf. case Bytecodes::_athrow in parse2.cpp.
513 uncommon_trap(reason, Deoptimization::Action_none,
514 (ciKlass*)NULL, (char*)NULL, must_throw);
515 }
516
517 }
518
519 //------------------------------builtin_throw----------------------------------
520 void GraphKit::builtin_throw(Deoptimization::DeoptReason reason, Node* arg) {
521 bool must_throw = true;
522
523 if (env()->jvmti_can_post_on_exceptions()) {
524 // check if we must post exception events, take uncommon trap if so
525 uncommon_trap_if_should_post_on_exceptions(reason, must_throw);
526 // here if should_post_on_exceptions is false
527 // continue on with the normal codegen
528 }
529
530 // If this particular condition has not yet happened at this
531 // bytecode, then use the uncommon trap mechanism, and allow for
532 // a future recompilation if several traps occur here.
533 // If the throw is hot, try to use a more complicated inline mechanism
534 // which keeps execution inside the compiled code.
535 bool treat_throw_as_hot = false;
536 ciMethodData* md = method()->method_data();
537
538 if (ProfileTraps) {
539 if (too_many_traps(reason)) {
540 treat_throw_as_hot = true;
541 }
542 // (If there is no MDO at all, assume it is early in
543 // execution, and that any deopts are part of the
544 // startup transient, and don't need to be remembered.)
545
546 // Also, if there is a local exception handler, treat all throws
547 // as hot if there has been at least one in this method.
548 if (C->trap_count(reason) != 0
549 && method()->method_data()->trap_count(reason) != 0
550 && has_ex_handler()) {
551 treat_throw_as_hot = true;
552 }
553 }
554
555 // If this throw happens frequently, an uncommon trap might cause
556 // a performance pothole. If there is a local exception handler,
557 // and if this particular bytecode appears to be deoptimizing often,
558 // let us handle the throw inline, with a preconstructed instance.
559 // Note: If the deopt count has blown up, the uncommon trap
560 // runtime is going to flush this nmethod, not matter what.
561 if (treat_throw_as_hot
562 && (!StackTraceInThrowable || OmitStackTraceInFastThrow)) {
563 // If the throw is local, we use a pre-existing instance and
564 // punt on the backtrace. This would lead to a missing backtrace
565 // (a repeat of 4292742) if the backtrace object is ever asked
566 // for its backtrace.
567 // Fixing this remaining case of 4292742 requires some flavor of
568 // escape analysis. Leave that for the future.
569 ciInstance* ex_obj = NULL;
570 switch (reason) {
571 case Deoptimization::Reason_null_check:
572 ex_obj = env()->NullPointerException_instance();
573 break;
574 case Deoptimization::Reason_div0_check:
575 ex_obj = env()->ArithmeticException_instance();
576 break;
577 case Deoptimization::Reason_range_check:
578 ex_obj = env()->ArrayIndexOutOfBoundsException_instance();
579 break;
580 case Deoptimization::Reason_class_check:
581 if (java_bc() == Bytecodes::_aastore) {
582 ex_obj = env()->ArrayStoreException_instance();
583 } else {
584 ex_obj = env()->ClassCastException_instance();
585 }
586 break;
587 default:
588 break;
589 }
590 if (failing()) { stop(); return; } // exception allocation might fail
591 if (ex_obj != NULL) {
592 // Cheat with a preallocated exception object.
593 if (C->log() != NULL)
594 C->log()->elem("hot_throw preallocated='1' reason='%s'",
595 Deoptimization::trap_reason_name(reason));
596 const TypeInstPtr* ex_con = TypeInstPtr::make(ex_obj);
597 Node* ex_node = _gvn.transform(ConNode::make(ex_con));
598
599 // Clear the detail message of the preallocated exception object.
600 // Weblogic sometimes mutates the detail message of exceptions
601 // using reflection.
602 int offset = java_lang_Throwable::get_detailMessage_offset();
603 const TypePtr* adr_typ = ex_con->add_offset(offset);
604
605 Node *adr = basic_plus_adr(ex_node, ex_node, offset);
606 const TypeOopPtr* val_type = TypeOopPtr::make_from_klass(env()->String_klass());
607 // Conservatively release stores of object references.
608 Node *store = store_oop_to_object(control(), ex_node, adr, adr_typ, null(), val_type, T_OBJECT, MemNode::release);
609
610 add_exception_state(make_exception_state(ex_node));
611 return;
612 }
613 }
614
615 // %%% Maybe add entry to OptoRuntime which directly throws the exc.?
616 // It won't be much cheaper than bailing to the interp., since we'll
617 // have to pass up all the debug-info, and the runtime will have to
618 // create the stack trace.
619
620 // Usual case: Bail to interpreter.
621 // Reserve the right to recompile if we haven't seen anything yet.
622
623 ciMethod* m = Deoptimization::reason_is_speculate(reason) ? C->method() : NULL;
624 Deoptimization::DeoptAction action = Deoptimization::Action_maybe_recompile;
625 if (treat_throw_as_hot
626 && (method()->method_data()->trap_recompiled_at(bci(), m)
627 || C->too_many_traps(reason))) {
628 // We cannot afford to take more traps here. Suffer in the interpreter.
629 if (C->log() != NULL)
630 C->log()->elem("hot_throw preallocated='0' reason='%s' mcount='%d'",
631 Deoptimization::trap_reason_name(reason),
632 C->trap_count(reason));
633 action = Deoptimization::Action_none;
634 }
635
636 // "must_throw" prunes the JVM state to include only the stack, if there
637 // are no local exception handlers. This should cut down on register
638 // allocation time and code size, by drastically reducing the number
639 // of in-edges on the call to the uncommon trap.
640
641 uncommon_trap(reason, action, (ciKlass*)NULL, (char*)NULL, must_throw);
642 }
643
644
645 //----------------------------PreserveJVMState---------------------------------
646 PreserveJVMState::PreserveJVMState(GraphKit* kit, bool clone_map) {
647 debug_only(kit->verify_map());
648 _kit = kit;
649 _map = kit->map(); // preserve the map
650 _sp = kit->sp();
651 kit->set_map(clone_map ? kit->clone_map() : NULL);
652 #ifdef ASSERT
653 _bci = kit->bci();
654 Parse* parser = kit->is_Parse();
655 int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo();
656 _block = block;
657 #endif
658 }
659 PreserveJVMState::~PreserveJVMState() {
660 GraphKit* kit = _kit;
661 #ifdef ASSERT
662 assert(kit->bci() == _bci, "bci must not shift");
663 Parse* parser = kit->is_Parse();
664 int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo();
665 assert(block == _block, "block must not shift");
666 #endif
667 kit->set_map(_map);
668 kit->set_sp(_sp);
669 }
670
671
672 //-----------------------------BuildCutout-------------------------------------
673 BuildCutout::BuildCutout(GraphKit* kit, Node* p, float prob, float cnt)
674 : PreserveJVMState(kit)
675 {
676 assert(p->is_Con() || p->is_Bool(), "test must be a bool");
677 SafePointNode* outer_map = _map; // preserved map is caller's
678 SafePointNode* inner_map = kit->map();
679 IfNode* iff = kit->create_and_map_if(outer_map->control(), p, prob, cnt);
680 outer_map->set_control(kit->gvn().transform( new IfTrueNode(iff) ));
681 inner_map->set_control(kit->gvn().transform( new IfFalseNode(iff) ));
682 }
683 BuildCutout::~BuildCutout() {
684 GraphKit* kit = _kit;
685 assert(kit->stopped(), "cutout code must stop, throw, return, etc.");
686 }
687
688 //---------------------------PreserveReexecuteState----------------------------
689 PreserveReexecuteState::PreserveReexecuteState(GraphKit* kit) {
690 assert(!kit->stopped(), "must call stopped() before");
691 _kit = kit;
692 _sp = kit->sp();
693 _reexecute = kit->jvms()->_reexecute;
694 }
695 PreserveReexecuteState::~PreserveReexecuteState() {
696 if (_kit->stopped()) return;
697 _kit->jvms()->_reexecute = _reexecute;
698 _kit->set_sp(_sp);
699 }
700
701 //------------------------------clone_map--------------------------------------
702 // Implementation of PreserveJVMState
703 //
704 // Only clone_map(...) here. If this function is only used in the
705 // PreserveJVMState class we may want to get rid of this extra
706 // function eventually and do it all there.
707
708 SafePointNode* GraphKit::clone_map() {
709 if (map() == NULL) return NULL;
710
711 // Clone the memory edge first
712 Node* mem = MergeMemNode::make(map()->memory());
713 gvn().set_type_bottom(mem);
714
715 SafePointNode *clonemap = (SafePointNode*)map()->clone();
716 JVMState* jvms = this->jvms();
717 JVMState* clonejvms = jvms->clone_shallow(C);
718 clonemap->set_memory(mem);
719 clonemap->set_jvms(clonejvms);
720 clonejvms->set_map(clonemap);
721 record_for_igvn(clonemap);
722 gvn().set_type_bottom(clonemap);
723 return clonemap;
724 }
725
726
727 //-----------------------------set_map_clone-----------------------------------
728 void GraphKit::set_map_clone(SafePointNode* m) {
729 _map = m;
730 _map = clone_map();
731 _map->set_next_exception(NULL);
732 debug_only(verify_map());
733 }
734
735
736 //----------------------------kill_dead_locals---------------------------------
737 // Detect any locals which are known to be dead, and force them to top.
738 void GraphKit::kill_dead_locals() {
739 // Consult the liveness information for the locals. If any
740 // of them are unused, then they can be replaced by top(). This
741 // should help register allocation time and cut down on the size
742 // of the deoptimization information.
743
744 // This call is made from many of the bytecode handling
745 // subroutines called from the Big Switch in do_one_bytecode.
746 // Every bytecode which might include a slow path is responsible
747 // for killing its dead locals. The more consistent we
748 // are about killing deads, the fewer useless phis will be
749 // constructed for them at various merge points.
750
751 // bci can be -1 (InvocationEntryBci). We return the entry
752 // liveness for the method.
753
754 if (method() == NULL || method()->code_size() == 0) {
755 // We are building a graph for a call to a native method.
756 // All locals are live.
757 return;
758 }
759
760 ResourceMark rm;
761
762 // Consult the liveness information for the locals. If any
763 // of them are unused, then they can be replaced by top(). This
764 // should help register allocation time and cut down on the size
765 // of the deoptimization information.
766 MethodLivenessResult live_locals = method()->liveness_at_bci(bci());
767
768 int len = (int)live_locals.size();
769 assert(len <= jvms()->loc_size(), "too many live locals");
770 for (int local = 0; local < len; local++) {
771 if (!live_locals.at(local)) {
772 set_local(local, top());
773 }
774 }
775 }
776
777 #ifdef ASSERT
778 //-------------------------dead_locals_are_killed------------------------------
779 // Return true if all dead locals are set to top in the map.
780 // Used to assert "clean" debug info at various points.
781 bool GraphKit::dead_locals_are_killed() {
782 if (method() == NULL || method()->code_size() == 0) {
783 // No locals need to be dead, so all is as it should be.
784 return true;
785 }
786
787 // Make sure somebody called kill_dead_locals upstream.
788 ResourceMark rm;
789 for (JVMState* jvms = this->jvms(); jvms != NULL; jvms = jvms->caller()) {
790 if (jvms->loc_size() == 0) continue; // no locals to consult
791 SafePointNode* map = jvms->map();
792 ciMethod* method = jvms->method();
793 int bci = jvms->bci();
794 if (jvms == this->jvms()) {
795 bci = this->bci(); // it might not yet be synched
796 }
797 MethodLivenessResult live_locals = method->liveness_at_bci(bci);
798 int len = (int)live_locals.size();
799 if (!live_locals.is_valid() || len == 0)
800 // This method is trivial, or is poisoned by a breakpoint.
801 return true;
802 assert(len == jvms->loc_size(), "live map consistent with locals map");
803 for (int local = 0; local < len; local++) {
804 if (!live_locals.at(local) && map->local(jvms, local) != top()) {
805 if (PrintMiscellaneous && (Verbose || WizardMode)) {
806 tty->print_cr("Zombie local %d: ", local);
807 jvms->dump();
808 }
809 return false;
810 }
811 }
812 }
813 return true;
814 }
815
816 #endif //ASSERT
817
818 // Helper function for enforcing certain bytecodes to reexecute if
819 // deoptimization happens
820 static bool should_reexecute_implied_by_bytecode(JVMState *jvms, bool is_anewarray) {
821 ciMethod* cur_method = jvms->method();
822 int cur_bci = jvms->bci();
823 if (cur_method != NULL && cur_bci != InvocationEntryBci) {
824 Bytecodes::Code code = cur_method->java_code_at_bci(cur_bci);
825 return Interpreter::bytecode_should_reexecute(code) ||
826 (is_anewarray && code == Bytecodes::_multianewarray);
827 // Reexecute _multianewarray bytecode which was replaced with
828 // sequence of [a]newarray. See Parse::do_multianewarray().
829 //
830 // Note: interpreter should not have it set since this optimization
831 // is limited by dimensions and guarded by flag so in some cases
832 // multianewarray() runtime calls will be generated and
833 // the bytecode should not be reexecutes (stack will not be reset).
834 } else
835 return false;
836 }
837
838 // Helper function for adding JVMState and debug information to node
839 void GraphKit::add_safepoint_edges(SafePointNode* call, bool must_throw) {
840 // Add the safepoint edges to the call (or other safepoint).
841
842 // Make sure dead locals are set to top. This
843 // should help register allocation time and cut down on the size
844 // of the deoptimization information.
845 assert(dead_locals_are_killed(), "garbage in debug info before safepoint");
846
847 // Walk the inline list to fill in the correct set of JVMState's
848 // Also fill in the associated edges for each JVMState.
849
850 // If the bytecode needs to be reexecuted we need to put
851 // the arguments back on the stack.
852 const bool should_reexecute = jvms()->should_reexecute();
853 JVMState* youngest_jvms = should_reexecute ? sync_jvms_for_reexecute() : sync_jvms();
854
855 // NOTE: set_bci (called from sync_jvms) might reset the reexecute bit to
856 // undefined if the bci is different. This is normal for Parse but it
857 // should not happen for LibraryCallKit because only one bci is processed.
858 assert(!is_LibraryCallKit() || (jvms()->should_reexecute() == should_reexecute),
859 "in LibraryCallKit the reexecute bit should not change");
860
861 // If we are guaranteed to throw, we can prune everything but the
862 // input to the current bytecode.
863 bool can_prune_locals = false;
864 uint stack_slots_not_pruned = 0;
865 int inputs = 0, depth = 0;
866 if (must_throw) {
867 assert(method() == youngest_jvms->method(), "sanity");
868 if (compute_stack_effects(inputs, depth)) {
869 can_prune_locals = true;
870 stack_slots_not_pruned = inputs;
871 }
872 }
873
874 if (env()->should_retain_local_variables()) {
875 // At any safepoint, this method can get breakpointed, which would
876 // then require an immediate deoptimization.
877 can_prune_locals = false; // do not prune locals
878 stack_slots_not_pruned = 0;
879 }
880
881 // do not scribble on the input jvms
882 JVMState* out_jvms = youngest_jvms->clone_deep(C);
883 call->set_jvms(out_jvms); // Start jvms list for call node
884
885 // For a known set of bytecodes, the interpreter should reexecute them if
886 // deoptimization happens. We set the reexecute state for them here
887 if (out_jvms->is_reexecute_undefined() && //don't change if already specified
888 should_reexecute_implied_by_bytecode(out_jvms, call->is_AllocateArray())) {
889 out_jvms->set_should_reexecute(true); //NOTE: youngest_jvms not changed
890 }
891
892 // Presize the call:
893 DEBUG_ONLY(uint non_debug_edges = call->req());
894 call->add_req_batch(top(), youngest_jvms->debug_depth());
895 assert(call->req() == non_debug_edges + youngest_jvms->debug_depth(), "");
896
897 // Set up edges so that the call looks like this:
898 // Call [state:] ctl io mem fptr retadr
899 // [parms:] parm0 ... parmN
900 // [root:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
901 // [...mid:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN [...]
902 // [young:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
903 // Note that caller debug info precedes callee debug info.
904
905 // Fill pointer walks backwards from "young:" to "root:" in the diagram above:
906 uint debug_ptr = call->req();
907
908 // Loop over the map input edges associated with jvms, add them
909 // to the call node, & reset all offsets to match call node array.
910 for (JVMState* in_jvms = youngest_jvms; in_jvms != NULL; ) {
911 uint debug_end = debug_ptr;
912 uint debug_start = debug_ptr - in_jvms->debug_size();
913 debug_ptr = debug_start; // back up the ptr
914
915 uint p = debug_start; // walks forward in [debug_start, debug_end)
916 uint j, k, l;
917 SafePointNode* in_map = in_jvms->map();
918 out_jvms->set_map(call);
919
920 if (can_prune_locals) {
921 assert(in_jvms->method() == out_jvms->method(), "sanity");
922 // If the current throw can reach an exception handler in this JVMS,
923 // then we must keep everything live that can reach that handler.
924 // As a quick and dirty approximation, we look for any handlers at all.
925 if (in_jvms->method()->has_exception_handlers()) {
926 can_prune_locals = false;
927 }
928 }
929
930 // Add the Locals
931 k = in_jvms->locoff();
932 l = in_jvms->loc_size();
933 out_jvms->set_locoff(p);
934 if (!can_prune_locals) {
935 for (j = 0; j < l; j++)
936 call->set_req(p++, in_map->in(k+j));
937 } else {
938 p += l; // already set to top above by add_req_batch
939 }
940
941 // Add the Expression Stack
942 k = in_jvms->stkoff();
943 l = in_jvms->sp();
944 out_jvms->set_stkoff(p);
945 if (!can_prune_locals) {
946 for (j = 0; j < l; j++)
947 call->set_req(p++, in_map->in(k+j));
948 } else if (can_prune_locals && stack_slots_not_pruned != 0) {
949 // Divide stack into {S0,...,S1}, where S0 is set to top.
950 uint s1 = stack_slots_not_pruned;
951 stack_slots_not_pruned = 0; // for next iteration
952 if (s1 > l) s1 = l;
953 uint s0 = l - s1;
954 p += s0; // skip the tops preinstalled by add_req_batch
955 for (j = s0; j < l; j++)
956 call->set_req(p++, in_map->in(k+j));
957 } else {
958 p += l; // already set to top above by add_req_batch
959 }
960
961 // Add the Monitors
962 k = in_jvms->monoff();
963 l = in_jvms->mon_size();
964 out_jvms->set_monoff(p);
965 for (j = 0; j < l; j++)
966 call->set_req(p++, in_map->in(k+j));
967
968 // Copy any scalar object fields.
969 k = in_jvms->scloff();
970 l = in_jvms->scl_size();
971 out_jvms->set_scloff(p);
972 for (j = 0; j < l; j++)
973 call->set_req(p++, in_map->in(k+j));
974
975 // Finish the new jvms.
976 out_jvms->set_endoff(p);
977
978 assert(out_jvms->endoff() == debug_end, "fill ptr must match");
979 assert(out_jvms->depth() == in_jvms->depth(), "depth must match");
980 assert(out_jvms->loc_size() == in_jvms->loc_size(), "size must match");
981 assert(out_jvms->mon_size() == in_jvms->mon_size(), "size must match");
982 assert(out_jvms->scl_size() == in_jvms->scl_size(), "size must match");
983 assert(out_jvms->debug_size() == in_jvms->debug_size(), "size must match");
984
985 // Update the two tail pointers in parallel.
986 out_jvms = out_jvms->caller();
987 in_jvms = in_jvms->caller();
988 }
989
990 assert(debug_ptr == non_debug_edges, "debug info must fit exactly");
991
992 // Test the correctness of JVMState::debug_xxx accessors:
993 assert(call->jvms()->debug_start() == non_debug_edges, "");
994 assert(call->jvms()->debug_end() == call->req(), "");
995 assert(call->jvms()->debug_depth() == call->req() - non_debug_edges, "");
996 }
997
998 bool GraphKit::compute_stack_effects(int& inputs, int& depth) {
999 Bytecodes::Code code = java_bc();
1000 if (code == Bytecodes::_wide) {
1001 code = method()->java_code_at_bci(bci() + 1);
1002 }
1003
1004 BasicType rtype = T_ILLEGAL;
1005 int rsize = 0;
1006
1007 if (code != Bytecodes::_illegal) {
1008 depth = Bytecodes::depth(code); // checkcast=0, athrow=-1
1009 rtype = Bytecodes::result_type(code); // checkcast=P, athrow=V
1010 if (rtype < T_CONFLICT)
1011 rsize = type2size[rtype];
1012 }
1013
1014 switch (code) {
1015 case Bytecodes::_illegal:
1016 return false;
1017
1018 case Bytecodes::_ldc:
1019 case Bytecodes::_ldc_w:
1020 case Bytecodes::_ldc2_w:
1021 inputs = 0;
1022 break;
1023
1024 case Bytecodes::_dup: inputs = 1; break;
1025 case Bytecodes::_dup_x1: inputs = 2; break;
1026 case Bytecodes::_dup_x2: inputs = 3; break;
1027 case Bytecodes::_dup2: inputs = 2; break;
1028 case Bytecodes::_dup2_x1: inputs = 3; break;
1029 case Bytecodes::_dup2_x2: inputs = 4; break;
1030 case Bytecodes::_swap: inputs = 2; break;
1031 case Bytecodes::_arraylength: inputs = 1; break;
1032
1033 case Bytecodes::_getstatic:
1034 case Bytecodes::_putstatic:
1035 case Bytecodes::_getfield:
1036 case Bytecodes::_putfield:
1037 {
1038 bool ignored_will_link;
1039 ciField* field = method()->get_field_at_bci(bci(), ignored_will_link);
1040 int size = field->type()->size();
1041 bool is_get = (depth >= 0), is_static = (depth & 1);
1042 inputs = (is_static ? 0 : 1);
1043 if (is_get) {
1044 depth = size - inputs;
1045 } else {
1046 inputs += size; // putxxx pops the value from the stack
1047 depth = - inputs;
1048 }
1049 }
1050 break;
1051
1052 case Bytecodes::_invokevirtual:
1053 case Bytecodes::_invokespecial:
1054 case Bytecodes::_invokestatic:
1055 case Bytecodes::_invokedynamic:
1056 case Bytecodes::_invokeinterface:
1057 {
1058 bool ignored_will_link;
1059 ciSignature* declared_signature = NULL;
1060 ciMethod* ignored_callee = method()->get_method_at_bci(bci(), ignored_will_link, &declared_signature);
1061 assert(declared_signature != NULL, "cannot be null");
1062 inputs = declared_signature->arg_size_for_bc(code);
1063 int size = declared_signature->return_type()->size();
1064 depth = size - inputs;
1065 }
1066 break;
1067
1068 case Bytecodes::_multianewarray:
1069 {
1070 ciBytecodeStream iter(method());
1071 iter.reset_to_bci(bci());
1072 iter.next();
1073 inputs = iter.get_dimensions();
1074 assert(rsize == 1, "");
1075 depth = rsize - inputs;
1076 }
1077 break;
1078
1079 case Bytecodes::_ireturn:
1080 case Bytecodes::_lreturn:
1081 case Bytecodes::_freturn:
1082 case Bytecodes::_dreturn:
1083 case Bytecodes::_areturn:
1084 assert(rsize == -depth, "");
1085 inputs = rsize;
1086 break;
1087
1088 case Bytecodes::_jsr:
1089 case Bytecodes::_jsr_w:
1090 inputs = 0;
1091 depth = 1; // S.B. depth=1, not zero
1092 break;
1093
1094 default:
1095 // bytecode produces a typed result
1096 inputs = rsize - depth;
1097 assert(inputs >= 0, "");
1098 break;
1099 }
1100
1101 #ifdef ASSERT
1102 // spot check
1103 int outputs = depth + inputs;
1104 assert(outputs >= 0, "sanity");
1105 switch (code) {
1106 case Bytecodes::_checkcast: assert(inputs == 1 && outputs == 1, ""); break;
1107 case Bytecodes::_athrow: assert(inputs == 1 && outputs == 0, ""); break;
1108 case Bytecodes::_aload_0: assert(inputs == 0 && outputs == 1, ""); break;
1109 case Bytecodes::_return: assert(inputs == 0 && outputs == 0, ""); break;
1110 case Bytecodes::_drem: assert(inputs == 4 && outputs == 2, ""); break;
1111 default: break;
1112 }
1113 #endif //ASSERT
1114
1115 return true;
1116 }
1117
1118
1119
1120 //------------------------------basic_plus_adr---------------------------------
1121 Node* GraphKit::basic_plus_adr(Node* base, Node* ptr, Node* offset) {
1122 // short-circuit a common case
1123 if (offset == intcon(0)) return ptr;
1124 return _gvn.transform( new AddPNode(base, ptr, offset) );
1125 }
1126
1127 Node* GraphKit::ConvI2L(Node* offset) {
1128 // short-circuit a common case
1129 jint offset_con = find_int_con(offset, Type::OffsetBot);
1130 if (offset_con != Type::OffsetBot) {
1131 return longcon((jlong) offset_con);
1132 }
1133 return _gvn.transform( new ConvI2LNode(offset));
1134 }
1135
1136 Node* GraphKit::ConvI2UL(Node* offset) {
1137 juint offset_con = (juint) find_int_con(offset, Type::OffsetBot);
1138 if (offset_con != (juint) Type::OffsetBot) {
1139 return longcon((julong) offset_con);
1140 }
1141 Node* conv = _gvn.transform( new ConvI2LNode(offset));
1142 Node* mask = _gvn.transform(ConLNode::make((julong) max_juint));
1143 return _gvn.transform( new AndLNode(conv, mask) );
1144 }
1145
1146 Node* GraphKit::ConvL2I(Node* offset) {
1147 // short-circuit a common case
1148 jlong offset_con = find_long_con(offset, (jlong)Type::OffsetBot);
1149 if (offset_con != (jlong)Type::OffsetBot) {
1150 return intcon((int) offset_con);
1151 }
1152 return _gvn.transform( new ConvL2INode(offset));
1153 }
1154
1155 //-------------------------load_object_klass-----------------------------------
1156 Node* GraphKit::load_object_klass(Node* obj) {
1157 // Special-case a fresh allocation to avoid building nodes:
1158 Node* akls = AllocateNode::Ideal_klass(obj, &_gvn);
1159 if (akls != NULL) return akls;
1160 Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes());
1161 return _gvn.transform(LoadKlassNode::make(_gvn, NULL, immutable_memory(), k_adr, TypeInstPtr::KLASS));
1162 }
1163
1164 //-------------------------load_array_length-----------------------------------
1165 Node* GraphKit::load_array_length(Node* array) {
1166 // Special-case a fresh allocation to avoid building nodes:
1167 AllocateArrayNode* alloc = AllocateArrayNode::Ideal_array_allocation(array, &_gvn);
1168 Node *alen;
1169 if (alloc == NULL) {
1170 Node *r_adr = basic_plus_adr(array, arrayOopDesc::length_offset_in_bytes());
1171 alen = _gvn.transform( new LoadRangeNode(0, immutable_memory(), r_adr, TypeInt::POS));
1172 } else {
1173 alen = alloc->Ideal_length();
1174 Node* ccast = alloc->make_ideal_length(_gvn.type(array)->is_oopptr(), &_gvn);
1175 if (ccast != alen) {
1176 alen = _gvn.transform(ccast);
1177 }
1178 }
1179 return alen;
1180 }
1181
1182 //------------------------------do_null_check----------------------------------
1183 // Helper function to do a NULL pointer check. Returned value is
1184 // the incoming address with NULL casted away. You are allowed to use the
1185 // not-null value only if you are control dependent on the test.
1186 #ifndef PRODUCT
1187 extern int explicit_null_checks_inserted,
1188 explicit_null_checks_elided;
1189 #endif
1190 Node* GraphKit::null_check_common(Node* value, BasicType type,
1191 // optional arguments for variations:
1192 bool assert_null,
1193 Node* *null_control,
1194 bool speculative) {
1195 assert(!assert_null || null_control == NULL, "not both at once");
1196 if (stopped()) return top();
1197 NOT_PRODUCT(explicit_null_checks_inserted++);
1198
1199 // Construct NULL check
1200 Node *chk = NULL;
1201 switch(type) {
1202 case T_LONG : chk = new CmpLNode(value, _gvn.zerocon(T_LONG)); break;
1203 case T_INT : chk = new CmpINode(value, _gvn.intcon(0)); break;
1204 case T_ARRAY : // fall through
1205 type = T_OBJECT; // simplify further tests
1206 case T_OBJECT : {
1207 const Type *t = _gvn.type( value );
1208
1209 const TypeOopPtr* tp = t->isa_oopptr();
1210 if (tp != NULL && tp->klass() != NULL && !tp->klass()->is_loaded()
1211 // Only for do_null_check, not any of its siblings:
1212 && !assert_null && null_control == NULL) {
1213 // Usually, any field access or invocation on an unloaded oop type
1214 // will simply fail to link, since the statically linked class is
1215 // likely also to be unloaded. However, in -Xcomp mode, sometimes
1216 // the static class is loaded but the sharper oop type is not.
1217 // Rather than checking for this obscure case in lots of places,
1218 // we simply observe that a null check on an unloaded class
1219 // will always be followed by a nonsense operation, so we
1220 // can just issue the uncommon trap here.
1221 // Our access to the unloaded class will only be correct
1222 // after it has been loaded and initialized, which requires
1223 // a trip through the interpreter.
1224 #ifndef PRODUCT
1225 if (WizardMode) { tty->print("Null check of unloaded "); tp->klass()->print(); tty->cr(); }
1226 #endif
1227 uncommon_trap(Deoptimization::Reason_unloaded,
1228 Deoptimization::Action_reinterpret,
1229 tp->klass(), "!loaded");
1230 return top();
1231 }
1232
1233 if (assert_null) {
1234 // See if the type is contained in NULL_PTR.
1235 // If so, then the value is already null.
1236 if (t->higher_equal(TypePtr::NULL_PTR)) {
1237 NOT_PRODUCT(explicit_null_checks_elided++);
1238 return value; // Elided null assert quickly!
1239 }
1240 } else {
1241 // See if mixing in the NULL pointer changes type.
1242 // If so, then the NULL pointer was not allowed in the original
1243 // type. In other words, "value" was not-null.
1244 if (t->meet(TypePtr::NULL_PTR) != t->remove_speculative()) {
1245 // same as: if (!TypePtr::NULL_PTR->higher_equal(t)) ...
1246 NOT_PRODUCT(explicit_null_checks_elided++);
1247 return value; // Elided null check quickly!
1248 }
1249 }
1250 chk = new CmpPNode( value, null() );
1251 break;
1252 }
1253
1254 default:
1255 fatal("unexpected type: %s", type2name(type));
1256 }
1257 assert(chk != NULL, "sanity check");
1258 chk = _gvn.transform(chk);
1259
1260 BoolTest::mask btest = assert_null ? BoolTest::eq : BoolTest::ne;
1261 BoolNode *btst = new BoolNode( chk, btest);
1262 Node *tst = _gvn.transform( btst );
1263
1264 //-----------
1265 // if peephole optimizations occurred, a prior test existed.
1266 // If a prior test existed, maybe it dominates as we can avoid this test.
1267 if (tst != btst && type == T_OBJECT) {
1268 // At this point we want to scan up the CFG to see if we can
1269 // find an identical test (and so avoid this test altogether).
1270 Node *cfg = control();
1271 int depth = 0;
1272 while( depth < 16 ) { // Limit search depth for speed
1273 if( cfg->Opcode() == Op_IfTrue &&
1274 cfg->in(0)->in(1) == tst ) {
1275 // Found prior test. Use "cast_not_null" to construct an identical
1276 // CastPP (and hence hash to) as already exists for the prior test.
1277 // Return that casted value.
1278 if (assert_null) {
1279 replace_in_map(value, null());
1280 return null(); // do not issue the redundant test
1281 }
1282 Node *oldcontrol = control();
1283 set_control(cfg);
1284 Node *res = cast_not_null(value);
1285 set_control(oldcontrol);
1286 NOT_PRODUCT(explicit_null_checks_elided++);
1287 return res;
1288 }
1289 cfg = IfNode::up_one_dom(cfg, /*linear_only=*/ true);
1290 if (cfg == NULL) break; // Quit at region nodes
1291 depth++;
1292 }
1293 }
1294
1295 //-----------
1296 // Branch to failure if null
1297 float ok_prob = PROB_MAX; // a priori estimate: nulls never happen
1298 Deoptimization::DeoptReason reason;
1299 if (assert_null) {
1300 reason = Deoptimization::reason_null_assert(speculative);
1301 } else if (type == T_OBJECT) {
1302 reason = Deoptimization::reason_null_check(speculative);
1303 } else {
1304 reason = Deoptimization::Reason_div0_check;
1305 }
1306 // %%% Since Reason_unhandled is not recorded on a per-bytecode basis,
1307 // ciMethodData::has_trap_at will return a conservative -1 if any
1308 // must-be-null assertion has failed. This could cause performance
1309 // problems for a method after its first do_null_assert failure.
1310 // Consider using 'Reason_class_check' instead?
1311
1312 // To cause an implicit null check, we set the not-null probability
1313 // to the maximum (PROB_MAX). For an explicit check the probability
1314 // is set to a smaller value.
1315 if (null_control != NULL || too_many_traps(reason)) {
1316 // probability is less likely
1317 ok_prob = PROB_LIKELY_MAG(3);
1318 } else if (!assert_null &&
1319 (ImplicitNullCheckThreshold > 0) &&
1320 method() != NULL &&
1321 (method()->method_data()->trap_count(reason)
1322 >= (uint)ImplicitNullCheckThreshold)) {
1323 ok_prob = PROB_LIKELY_MAG(3);
1324 }
1325
1326 if (null_control != NULL) {
1327 IfNode* iff = create_and_map_if(control(), tst, ok_prob, COUNT_UNKNOWN);
1328 Node* null_true = _gvn.transform( new IfFalseNode(iff));
1329 set_control( _gvn.transform( new IfTrueNode(iff)));
1330 #ifndef PRODUCT
1331 if (null_true == top()) {
1332 explicit_null_checks_elided++;
1333 }
1334 #endif
1335 (*null_control) = null_true;
1336 } else {
1337 BuildCutout unless(this, tst, ok_prob);
1338 // Check for optimizer eliding test at parse time
1339 if (stopped()) {
1340 // Failure not possible; do not bother making uncommon trap.
1341 NOT_PRODUCT(explicit_null_checks_elided++);
1342 } else if (assert_null) {
1343 uncommon_trap(reason,
1344 Deoptimization::Action_make_not_entrant,
1345 NULL, "assert_null");
1346 } else {
1347 replace_in_map(value, zerocon(type));
1348 builtin_throw(reason);
1349 }
1350 }
1351
1352 // Must throw exception, fall-thru not possible?
1353 if (stopped()) {
1354 return top(); // No result
1355 }
1356
1357 if (assert_null) {
1358 // Cast obj to null on this path.
1359 replace_in_map(value, zerocon(type));
1360 return zerocon(type);
1361 }
1362
1363 // Cast obj to not-null on this path, if there is no null_control.
1364 // (If there is a null_control, a non-null value may come back to haunt us.)
1365 if (type == T_OBJECT) {
1366 Node* cast = cast_not_null(value, false);
1367 if (null_control == NULL || (*null_control) == top())
1368 replace_in_map(value, cast);
1369 value = cast;
1370 }
1371
1372 return value;
1373 }
1374
1375
1376 //------------------------------cast_not_null----------------------------------
1377 // Cast obj to not-null on this path
1378 Node* GraphKit::cast_not_null(Node* obj, bool do_replace_in_map) {
1379 const Type *t = _gvn.type(obj);
1380 const Type *t_not_null = t->join_speculative(TypePtr::NOTNULL);
1381 // Object is already not-null?
1382 if( t == t_not_null ) return obj;
1383
1384 Node *cast = new CastPPNode(obj,t_not_null);
1385 cast->init_req(0, control());
1386 cast = _gvn.transform( cast );
1387
1388 // Scan for instances of 'obj' in the current JVM mapping.
1389 // These instances are known to be not-null after the test.
1390 if (do_replace_in_map)
1391 replace_in_map(obj, cast);
1392
1393 return cast; // Return casted value
1394 }
1395
1396 // Sometimes in intrinsics, we implicitly know an object is not null
1397 // (there's no actual null check) so we can cast it to not null. In
1398 // the course of optimizations, the input to the cast can become null.
1399 // In that case that data path will die and we need the control path
1400 // to become dead as well to keep the graph consistent. So we have to
1401 // add a check for null for which one branch can't be taken. It uses
1402 // an Opaque4 node that will cause the check to be removed after loop
1403 // opts so the test goes away and the compiled code doesn't execute a
1404 // useless check.
1405 Node* GraphKit::must_be_not_null(Node* value, bool do_replace_in_map) {
1406 Node* chk = _gvn.transform(new CmpPNode(value, null()));
1407 Node *tst = _gvn.transform(new BoolNode(chk, BoolTest::ne));
1408 Node* opaq = _gvn.transform(new Opaque4Node(C, tst, intcon(1)));
1409 IfNode *iff = new IfNode(control(), opaq, PROB_MAX, COUNT_UNKNOWN);
1410 _gvn.set_type(iff, iff->Value(&_gvn));
1411 Node *if_f = _gvn.transform(new IfFalseNode(iff));
1412 Node *frame = _gvn.transform(new ParmNode(C->start(), TypeFunc::FramePtr));
1413 Node *halt = _gvn.transform(new HaltNode(if_f, frame));
1414 C->root()->add_req(halt);
1415 Node *if_t = _gvn.transform(new IfTrueNode(iff));
1416 set_control(if_t);
1417 return cast_not_null(value, do_replace_in_map);
1418 }
1419
1420
1421 //--------------------------replace_in_map-------------------------------------
1422 void GraphKit::replace_in_map(Node* old, Node* neww) {
1423 if (old == neww) {
1424 return;
1425 }
1426
1427 map()->replace_edge(old, neww);
1428
1429 // Note: This operation potentially replaces any edge
1430 // on the map. This includes locals, stack, and monitors
1431 // of the current (innermost) JVM state.
1432
1433 // don't let inconsistent types from profiling escape this
1434 // method
1435
1436 const Type* told = _gvn.type(old);
1437 const Type* tnew = _gvn.type(neww);
1438
1439 if (!tnew->higher_equal(told)) {
1440 return;
1441 }
1442
1443 map()->record_replaced_node(old, neww);
1444 }
1445
1446
1447 //=============================================================================
1448 //--------------------------------memory---------------------------------------
1449 Node* GraphKit::memory(uint alias_idx) {
1450 MergeMemNode* mem = merged_memory();
1451 Node* p = mem->memory_at(alias_idx);
1452 _gvn.set_type(p, Type::MEMORY); // must be mapped
1453 return p;
1454 }
1455
1456 //-----------------------------reset_memory------------------------------------
1457 Node* GraphKit::reset_memory() {
1458 Node* mem = map()->memory();
1459 // do not use this node for any more parsing!
1460 debug_only( map()->set_memory((Node*)NULL) );
1461 return _gvn.transform( mem );
1462 }
1463
1464 //------------------------------set_all_memory---------------------------------
1465 void GraphKit::set_all_memory(Node* newmem) {
1466 Node* mergemem = MergeMemNode::make(newmem);
1467 gvn().set_type_bottom(mergemem);
1468 map()->set_memory(mergemem);
1469 }
1470
1471 //------------------------------set_all_memory_call----------------------------
1472 void GraphKit::set_all_memory_call(Node* call, bool separate_io_proj) {
1473 Node* newmem = _gvn.transform( new ProjNode(call, TypeFunc::Memory, separate_io_proj) );
1474 set_all_memory(newmem);
1475 }
1476
1477 //=============================================================================
1478 //
1479 // parser factory methods for MemNodes
1480 //
1481 // These are layered on top of the factory methods in LoadNode and StoreNode,
1482 // and integrate with the parser's memory state and _gvn engine.
1483 //
1484
1485 // factory methods in "int adr_idx"
1486 Node* GraphKit::make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
1487 int adr_idx,
1488 MemNode::MemOrd mo,
1489 LoadNode::ControlDependency control_dependency,
1490 bool require_atomic_access,
1491 bool unaligned,
1492 bool mismatched) {
1493 assert(adr_idx != Compile::AliasIdxTop, "use other make_load factory" );
1494 const TypePtr* adr_type = NULL; // debug-mode-only argument
1495 debug_only(adr_type = C->get_adr_type(adr_idx));
1496 Node* mem = memory(adr_idx);
1497 Node* ld;
1498 if (require_atomic_access && bt == T_LONG) {
1499 ld = LoadLNode::make_atomic(ctl, mem, adr, adr_type, t, mo, control_dependency, unaligned, mismatched);
1500 } else if (require_atomic_access && bt == T_DOUBLE) {
1501 ld = LoadDNode::make_atomic(ctl, mem, adr, adr_type, t, mo, control_dependency, unaligned, mismatched);
1502 } else {
1503 ld = LoadNode::make(_gvn, ctl, mem, adr, adr_type, t, bt, mo, control_dependency, unaligned, mismatched);
1504 }
1505 ld = _gvn.transform(ld);
1506 if (((bt == T_OBJECT) && C->do_escape_analysis()) || C->eliminate_boxing()) {
1507 // Improve graph before escape analysis and boxing elimination.
1508 record_for_igvn(ld);
1509 }
1510 return ld;
1511 }
1512
1513 Node* GraphKit::store_to_memory(Node* ctl, Node* adr, Node *val, BasicType bt,
1514 int adr_idx,
1515 MemNode::MemOrd mo,
1516 bool require_atomic_access,
1517 bool unaligned,
1518 bool mismatched) {
1519 assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1520 const TypePtr* adr_type = NULL;
1521 debug_only(adr_type = C->get_adr_type(adr_idx));
1522 Node *mem = memory(adr_idx);
1523 Node* st;
1524 if (require_atomic_access && bt == T_LONG) {
1525 st = StoreLNode::make_atomic(ctl, mem, adr, adr_type, val, mo);
1526 } else if (require_atomic_access && bt == T_DOUBLE) {
1527 st = StoreDNode::make_atomic(ctl, mem, adr, adr_type, val, mo);
1528 } else {
1529 st = StoreNode::make(_gvn, ctl, mem, adr, adr_type, val, bt, mo);
1530 }
1531 if (unaligned) {
1532 st->as_Store()->set_unaligned_access();
1533 }
1534 if (mismatched) {
1535 st->as_Store()->set_mismatched_access();
1536 }
1537 st = _gvn.transform(st);
1538 set_memory(st, adr_idx);
1539 // Back-to-back stores can only remove intermediate store with DU info
1540 // so push on worklist for optimizer.
1541 if (mem->req() > MemNode::Address && adr == mem->in(MemNode::Address))
1542 record_for_igvn(st);
1543
1544 return st;
1545 }
1546
1547
1548 void GraphKit::pre_barrier(bool do_load,
1549 Node* ctl,
1550 Node* obj,
1551 Node* adr,
1552 uint adr_idx,
1553 Node* val,
1554 const TypeOopPtr* val_type,
1555 Node* pre_val,
1556 BasicType bt) {
1557
1558 BarrierSet* bs = Universe::heap()->barrier_set();
1559 set_control(ctl);
1560 switch (bs->kind()) {
1561 case BarrierSet::G1SATBCTLogging:
1562 g1_write_barrier_pre(do_load, obj, adr, adr_idx, val, val_type, pre_val, bt);
1563 break;
1564
1565 case BarrierSet::CardTableForRS:
1566 case BarrierSet::CardTableExtension:
1567 case BarrierSet::ModRef:
1568 break;
1569
1570 default :
1571 ShouldNotReachHere();
1572
1573 }
1574 }
1575
1576 bool GraphKit::can_move_pre_barrier() const {
1577 BarrierSet* bs = Universe::heap()->barrier_set();
1578 switch (bs->kind()) {
1579 case BarrierSet::G1SATBCTLogging:
1580 return true; // Can move it if no safepoint
1581
1582 case BarrierSet::CardTableForRS:
1583 case BarrierSet::CardTableExtension:
1584 case BarrierSet::ModRef:
1585 return true; // There is no pre-barrier
1586
1587 default :
1588 ShouldNotReachHere();
1589 }
1590 return false;
1591 }
1592
1593 void GraphKit::post_barrier(Node* ctl,
1594 Node* store,
1595 Node* obj,
1596 Node* adr,
1597 uint adr_idx,
1598 Node* val,
1599 BasicType bt,
1600 bool use_precise) {
1601 BarrierSet* bs = Universe::heap()->barrier_set();
1602 set_control(ctl);
1603 switch (bs->kind()) {
1604 case BarrierSet::G1SATBCTLogging:
1605 g1_write_barrier_post(store, obj, adr, adr_idx, val, bt, use_precise);
1606 break;
1607
1608 case BarrierSet::CardTableForRS:
1609 case BarrierSet::CardTableExtension:
1610 write_barrier_post(store, obj, adr, adr_idx, val, use_precise);
1611 break;
1612
1613 case BarrierSet::ModRef:
1614 break;
1615
1616 default :
1617 ShouldNotReachHere();
1618
1619 }
1620 }
1621
1622 Node* GraphKit::store_oop(Node* ctl,
1623 Node* obj,
1624 Node* adr,
1625 const TypePtr* adr_type,
1626 Node* val,
1627 const TypeOopPtr* val_type,
1628 BasicType bt,
1629 bool use_precise,
1630 MemNode::MemOrd mo,
1631 bool mismatched) {
1632 // Transformation of a value which could be NULL pointer (CastPP #NULL)
1633 // could be delayed during Parse (for example, in adjust_map_after_if()).
1634 // Execute transformation here to avoid barrier generation in such case.
1635 if (_gvn.type(val) == TypePtr::NULL_PTR)
1636 val = _gvn.makecon(TypePtr::NULL_PTR);
1637
1638 set_control(ctl);
1639 if (stopped()) return top(); // Dead path ?
1640
1641 assert(bt == T_OBJECT, "sanity");
1642 assert(val != NULL, "not dead path");
1643 uint adr_idx = C->get_alias_index(adr_type);
1644 assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1645
1646 pre_barrier(true /* do_load */,
1647 control(), obj, adr, adr_idx, val, val_type,
1648 NULL /* pre_val */,
1649 bt);
1650
1651 Node* store = store_to_memory(control(), adr, val, bt, adr_idx, mo, mismatched);
1652 post_barrier(control(), store, obj, adr, adr_idx, val, bt, use_precise);
1653 return store;
1654 }
1655
1656 // Could be an array or object we don't know at compile time (unsafe ref.)
1657 Node* GraphKit::store_oop_to_unknown(Node* ctl,
1658 Node* obj, // containing obj
1659 Node* adr, // actual adress to store val at
1660 const TypePtr* adr_type,
1661 Node* val,
1662 BasicType bt,
1663 MemNode::MemOrd mo,
1664 bool mismatched) {
1665 Compile::AliasType* at = C->alias_type(adr_type);
1666 const TypeOopPtr* val_type = NULL;
1667 if (adr_type->isa_instptr()) {
1668 if (at->field() != NULL) {
1669 // known field. This code is a copy of the do_put_xxx logic.
1670 ciField* field = at->field();
1671 if (!field->type()->is_loaded()) {
1672 val_type = TypeInstPtr::BOTTOM;
1673 } else {
1674 val_type = TypeOopPtr::make_from_klass(field->type()->as_klass());
1675 }
1676 }
1677 } else if (adr_type->isa_aryptr()) {
1678 val_type = adr_type->is_aryptr()->elem()->make_oopptr();
1679 }
1680 if (val_type == NULL) {
1681 val_type = TypeInstPtr::BOTTOM;
1682 }
1683 return store_oop(ctl, obj, adr, adr_type, val, val_type, bt, true, mo, mismatched);
1684 }
1685
1686
1687 //-------------------------array_element_address-------------------------
1688 Node* GraphKit::array_element_address(Node* ary, Node* idx, BasicType elembt,
1689 const TypeInt* sizetype, Node* ctrl) {
1690 uint shift = exact_log2(type2aelembytes(elembt));
1691 uint header = arrayOopDesc::base_offset_in_bytes(elembt);
1692
1693 // short-circuit a common case (saves lots of confusing waste motion)
1694 jint idx_con = find_int_con(idx, -1);
1695 if (idx_con >= 0) {
1696 intptr_t offset = header + ((intptr_t)idx_con << shift);
1697 return basic_plus_adr(ary, offset);
1698 }
1699
1700 // must be correct type for alignment purposes
1701 Node* base = basic_plus_adr(ary, header);
1702 idx = Compile::conv_I2X_index(&_gvn, idx, sizetype, ctrl);
1703 Node* scale = _gvn.transform( new LShiftXNode(idx, intcon(shift)) );
1704 return basic_plus_adr(ary, base, scale);
1705 }
1706
1707 //-------------------------load_array_element-------------------------
1708 Node* GraphKit::load_array_element(Node* ctl, Node* ary, Node* idx, const TypeAryPtr* arytype) {
1709 const Type* elemtype = arytype->elem();
1710 BasicType elembt = elemtype->array_element_basic_type();
1711 Node* adr = array_element_address(ary, idx, elembt, arytype->size());
1712 if (elembt == T_NARROWOOP) {
1713 elembt = T_OBJECT; // To satisfy switch in LoadNode::make()
1714 }
1715 Node* ld = make_load(ctl, adr, elemtype, elembt, arytype, MemNode::unordered);
1716 return ld;
1717 }
1718
1719 //-------------------------set_arguments_for_java_call-------------------------
1720 // Arguments (pre-popped from the stack) are taken from the JVMS.
1721 void GraphKit::set_arguments_for_java_call(CallJavaNode* call) {
1722 // Add the call arguments:
1723 uint nargs = call->method()->arg_size();
1724 for (uint i = 0; i < nargs; i++) {
1725 Node* arg = argument(i);
1726 call->init_req(i + TypeFunc::Parms, arg);
1727 }
1728 }
1729
1730 //---------------------------set_edges_for_java_call---------------------------
1731 // Connect a newly created call into the current JVMS.
1732 // A return value node (if any) is returned from set_edges_for_java_call.
1733 void GraphKit::set_edges_for_java_call(CallJavaNode* call, bool must_throw, bool separate_io_proj) {
1734
1735 // Add the predefined inputs:
1736 call->init_req( TypeFunc::Control, control() );
1737 call->init_req( TypeFunc::I_O , i_o() );
1738 call->init_req( TypeFunc::Memory , reset_memory() );
1739 call->init_req( TypeFunc::FramePtr, frameptr() );
1740 call->init_req( TypeFunc::ReturnAdr, top() );
1741
1742 add_safepoint_edges(call, must_throw);
1743
1744 Node* xcall = _gvn.transform(call);
1745
1746 if (xcall == top()) {
1747 set_control(top());
1748 return;
1749 }
1750 assert(xcall == call, "call identity is stable");
1751
1752 // Re-use the current map to produce the result.
1753
1754 set_control(_gvn.transform(new ProjNode(call, TypeFunc::Control)));
1755 set_i_o( _gvn.transform(new ProjNode(call, TypeFunc::I_O , separate_io_proj)));
1756 set_all_memory_call(xcall, separate_io_proj);
1757
1758 //return xcall; // no need, caller already has it
1759 }
1760
1761 Node* GraphKit::set_results_for_java_call(CallJavaNode* call, bool separate_io_proj) {
1762 if (stopped()) return top(); // maybe the call folded up?
1763
1764 // Capture the return value, if any.
1765 Node* ret;
1766 if (call->method() == NULL ||
1767 call->method()->return_type()->basic_type() == T_VOID)
1768 ret = top();
1769 else ret = _gvn.transform(new ProjNode(call, TypeFunc::Parms));
1770
1771 // Note: Since any out-of-line call can produce an exception,
1772 // we always insert an I_O projection from the call into the result.
1773
1774 make_slow_call_ex(call, env()->Throwable_klass(), separate_io_proj);
1775
1776 if (separate_io_proj) {
1777 // The caller requested separate projections be used by the fall
1778 // through and exceptional paths, so replace the projections for
1779 // the fall through path.
1780 set_i_o(_gvn.transform( new ProjNode(call, TypeFunc::I_O) ));
1781 set_all_memory(_gvn.transform( new ProjNode(call, TypeFunc::Memory) ));
1782 }
1783 return ret;
1784 }
1785
1786 //--------------------set_predefined_input_for_runtime_call--------------------
1787 // Reading and setting the memory state is way conservative here.
1788 // The real problem is that I am not doing real Type analysis on memory,
1789 // so I cannot distinguish card mark stores from other stores. Across a GC
1790 // point the Store Barrier and the card mark memory has to agree. I cannot
1791 // have a card mark store and its barrier split across the GC point from
1792 // either above or below. Here I get that to happen by reading ALL of memory.
1793 // A better answer would be to separate out card marks from other memory.
1794 // For now, return the input memory state, so that it can be reused
1795 // after the call, if this call has restricted memory effects.
1796 Node* GraphKit::set_predefined_input_for_runtime_call(SafePointNode* call) {
1797 // Set fixed predefined input arguments
1798 Node* memory = reset_memory();
1799 call->init_req( TypeFunc::Control, control() );
1800 call->init_req( TypeFunc::I_O, top() ); // does no i/o
1801 call->init_req( TypeFunc::Memory, memory ); // may gc ptrs
1802 call->init_req( TypeFunc::FramePtr, frameptr() );
1803 call->init_req( TypeFunc::ReturnAdr, top() );
1804 return memory;
1805 }
1806
1807 //-------------------set_predefined_output_for_runtime_call--------------------
1808 // Set control and memory (not i_o) from the call.
1809 // If keep_mem is not NULL, use it for the output state,
1810 // except for the RawPtr output of the call, if hook_mem is TypeRawPtr::BOTTOM.
1811 // If hook_mem is NULL, this call produces no memory effects at all.
1812 // If hook_mem is a Java-visible memory slice (such as arraycopy operands),
1813 // then only that memory slice is taken from the call.
1814 // In the last case, we must put an appropriate memory barrier before
1815 // the call, so as to create the correct anti-dependencies on loads
1816 // preceding the call.
1817 void GraphKit::set_predefined_output_for_runtime_call(Node* call,
1818 Node* keep_mem,
1819 const TypePtr* hook_mem) {
1820 // no i/o
1821 set_control(_gvn.transform( new ProjNode(call,TypeFunc::Control) ));
1822 if (keep_mem) {
1823 // First clone the existing memory state
1824 set_all_memory(keep_mem);
1825 if (hook_mem != NULL) {
1826 // Make memory for the call
1827 Node* mem = _gvn.transform( new ProjNode(call, TypeFunc::Memory) );
1828 // Set the RawPtr memory state only. This covers all the heap top/GC stuff
1829 // We also use hook_mem to extract specific effects from arraycopy stubs.
1830 set_memory(mem, hook_mem);
1831 }
1832 // ...else the call has NO memory effects.
1833
1834 // Make sure the call advertises its memory effects precisely.
1835 // This lets us build accurate anti-dependences in gcm.cpp.
1836 assert(C->alias_type(call->adr_type()) == C->alias_type(hook_mem),
1837 "call node must be constructed correctly");
1838 } else {
1839 assert(hook_mem == NULL, "");
1840 // This is not a "slow path" call; all memory comes from the call.
1841 set_all_memory_call(call);
1842 }
1843 }
1844
1845
1846 // Replace the call with the current state of the kit.
1847 void GraphKit::replace_call(CallNode* call, Node* result, bool do_replaced_nodes) {
1848 JVMState* ejvms = NULL;
1849 if (has_exceptions()) {
1850 ejvms = transfer_exceptions_into_jvms();
1851 }
1852
1853 ReplacedNodes replaced_nodes = map()->replaced_nodes();
1854 ReplacedNodes replaced_nodes_exception;
1855 Node* ex_ctl = top();
1856
1857 SafePointNode* final_state = stop();
1858
1859 // Find all the needed outputs of this call
1860 CallProjections callprojs;
1861 call->extract_projections(&callprojs, true);
1862
1863 Node* init_mem = call->in(TypeFunc::Memory);
1864 Node* final_mem = final_state->in(TypeFunc::Memory);
1865 Node* final_ctl = final_state->in(TypeFunc::Control);
1866 Node* final_io = final_state->in(TypeFunc::I_O);
1867
1868 // Replace all the old call edges with the edges from the inlining result
1869 if (callprojs.fallthrough_catchproj != NULL) {
1870 C->gvn_replace_by(callprojs.fallthrough_catchproj, final_ctl);
1871 }
1872 if (callprojs.fallthrough_memproj != NULL) {
1873 if (final_mem->is_MergeMem()) {
1874 // Parser's exits MergeMem was not transformed but may be optimized
1875 final_mem = _gvn.transform(final_mem);
1876 }
1877 C->gvn_replace_by(callprojs.fallthrough_memproj, final_mem);
1878 }
1879 if (callprojs.fallthrough_ioproj != NULL) {
1880 C->gvn_replace_by(callprojs.fallthrough_ioproj, final_io);
1881 }
1882
1883 // Replace the result with the new result if it exists and is used
1884 if (callprojs.resproj != NULL && result != NULL) {
1885 C->gvn_replace_by(callprojs.resproj, result);
1886 }
1887
1888 if (ejvms == NULL) {
1889 // No exception edges to simply kill off those paths
1890 if (callprojs.catchall_catchproj != NULL) {
1891 C->gvn_replace_by(callprojs.catchall_catchproj, C->top());
1892 }
1893 if (callprojs.catchall_memproj != NULL) {
1894 C->gvn_replace_by(callprojs.catchall_memproj, C->top());
1895 }
1896 if (callprojs.catchall_ioproj != NULL) {
1897 C->gvn_replace_by(callprojs.catchall_ioproj, C->top());
1898 }
1899 // Replace the old exception object with top
1900 if (callprojs.exobj != NULL) {
1901 C->gvn_replace_by(callprojs.exobj, C->top());
1902 }
1903 } else {
1904 GraphKit ekit(ejvms);
1905
1906 // Load my combined exception state into the kit, with all phis transformed:
1907 SafePointNode* ex_map = ekit.combine_and_pop_all_exception_states();
1908 replaced_nodes_exception = ex_map->replaced_nodes();
1909
1910 Node* ex_oop = ekit.use_exception_state(ex_map);
1911
1912 if (callprojs.catchall_catchproj != NULL) {
1913 C->gvn_replace_by(callprojs.catchall_catchproj, ekit.control());
1914 ex_ctl = ekit.control();
1915 }
1916 if (callprojs.catchall_memproj != NULL) {
1917 C->gvn_replace_by(callprojs.catchall_memproj, ekit.reset_memory());
1918 }
1919 if (callprojs.catchall_ioproj != NULL) {
1920 C->gvn_replace_by(callprojs.catchall_ioproj, ekit.i_o());
1921 }
1922
1923 // Replace the old exception object with the newly created one
1924 if (callprojs.exobj != NULL) {
1925 C->gvn_replace_by(callprojs.exobj, ex_oop);
1926 }
1927 }
1928
1929 // Disconnect the call from the graph
1930 call->disconnect_inputs(NULL, C);
1931 C->gvn_replace_by(call, C->top());
1932
1933 // Clean up any MergeMems that feed other MergeMems since the
1934 // optimizer doesn't like that.
1935 if (final_mem->is_MergeMem()) {
1936 Node_List wl;
1937 for (SimpleDUIterator i(final_mem); i.has_next(); i.next()) {
1938 Node* m = i.get();
1939 if (m->is_MergeMem() && !wl.contains(m)) {
1940 wl.push(m);
1941 }
1942 }
1943 while (wl.size() > 0) {
1944 _gvn.transform(wl.pop());
1945 }
1946 }
1947
1948 if (callprojs.fallthrough_catchproj != NULL && !final_ctl->is_top() && do_replaced_nodes) {
1949 replaced_nodes.apply(C, final_ctl);
1950 }
1951 if (!ex_ctl->is_top() && do_replaced_nodes) {
1952 replaced_nodes_exception.apply(C, ex_ctl);
1953 }
1954 }
1955
1956
1957 //------------------------------increment_counter------------------------------
1958 // for statistics: increment a VM counter by 1
1959
1960 void GraphKit::increment_counter(address counter_addr) {
1961 Node* adr1 = makecon(TypeRawPtr::make(counter_addr));
1962 increment_counter(adr1);
1963 }
1964
1965 void GraphKit::increment_counter(Node* counter_addr) {
1966 int adr_type = Compile::AliasIdxRaw;
1967 Node* ctrl = control();
1968 Node* cnt = make_load(ctrl, counter_addr, TypeInt::INT, T_INT, adr_type, MemNode::unordered);
1969 Node* incr = _gvn.transform(new AddINode(cnt, _gvn.intcon(1)));
1970 store_to_memory(ctrl, counter_addr, incr, T_INT, adr_type, MemNode::unordered);
1971 }
1972
1973
1974 //------------------------------uncommon_trap----------------------------------
1975 // Bail out to the interpreter in mid-method. Implemented by calling the
1976 // uncommon_trap blob. This helper function inserts a runtime call with the
1977 // right debug info.
1978 void GraphKit::uncommon_trap(int trap_request,
1979 ciKlass* klass, const char* comment,
1980 bool must_throw,
1981 bool keep_exact_action) {
1982 if (failing()) stop();
1983 if (stopped()) return; // trap reachable?
1984
1985 // Note: If ProfileTraps is true, and if a deopt. actually
1986 // occurs here, the runtime will make sure an MDO exists. There is
1987 // no need to call method()->ensure_method_data() at this point.
1988
1989 // Set the stack pointer to the right value for reexecution:
1990 set_sp(reexecute_sp());
1991
1992 #ifdef ASSERT
1993 if (!must_throw) {
1994 // Make sure the stack has at least enough depth to execute
1995 // the current bytecode.
1996 int inputs, ignored_depth;
1997 if (compute_stack_effects(inputs, ignored_depth)) {
1998 assert(sp() >= inputs, "must have enough JVMS stack to execute %s: sp=%d, inputs=%d",
1999 Bytecodes::name(java_bc()), sp(), inputs);
2000 }
2001 }
2002 #endif
2003
2004 Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
2005 Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
2006
2007 switch (action) {
2008 case Deoptimization::Action_maybe_recompile:
2009 case Deoptimization::Action_reinterpret:
2010 // Temporary fix for 6529811 to allow virtual calls to be sure they
2011 // get the chance to go from mono->bi->mega
2012 if (!keep_exact_action &&
2013 Deoptimization::trap_request_index(trap_request) < 0 &&
2014 too_many_recompiles(reason)) {
2015 // This BCI is causing too many recompilations.
2016 if (C->log() != NULL) {
2017 C->log()->elem("observe that='trap_action_change' reason='%s' from='%s' to='none'",
2018 Deoptimization::trap_reason_name(reason),
2019 Deoptimization::trap_action_name(action));
2020 }
2021 action = Deoptimization::Action_none;
2022 trap_request = Deoptimization::make_trap_request(reason, action);
2023 } else {
2024 C->set_trap_can_recompile(true);
2025 }
2026 break;
2027 case Deoptimization::Action_make_not_entrant:
2028 C->set_trap_can_recompile(true);
2029 break;
2030 case Deoptimization::Action_none:
2031 case Deoptimization::Action_make_not_compilable:
2032 break;
2033 default:
2034 #ifdef ASSERT
2035 fatal("unknown action %d: %s", action, Deoptimization::trap_action_name(action));
2036 #endif
2037 break;
2038 }
2039
2040 if (TraceOptoParse) {
2041 char buf[100];
2042 tty->print_cr("Uncommon trap %s at bci:%d",
2043 Deoptimization::format_trap_request(buf, sizeof(buf),
2044 trap_request), bci());
2045 }
2046
2047 CompileLog* log = C->log();
2048 if (log != NULL) {
2049 int kid = (klass == NULL)? -1: log->identify(klass);
2050 log->begin_elem("uncommon_trap bci='%d'", bci());
2051 char buf[100];
2052 log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf),
2053 trap_request));
2054 if (kid >= 0) log->print(" klass='%d'", kid);
2055 if (comment != NULL) log->print(" comment='%s'", comment);
2056 log->end_elem();
2057 }
2058
2059 // Make sure any guarding test views this path as very unlikely
2060 Node *i0 = control()->in(0);
2061 if (i0 != NULL && i0->is_If()) { // Found a guarding if test?
2062 IfNode *iff = i0->as_If();
2063 float f = iff->_prob; // Get prob
2064 if (control()->Opcode() == Op_IfTrue) {
2065 if (f > PROB_UNLIKELY_MAG(4))
2066 iff->_prob = PROB_MIN;
2067 } else {
2068 if (f < PROB_LIKELY_MAG(4))
2069 iff->_prob = PROB_MAX;
2070 }
2071 }
2072
2073 // Clear out dead values from the debug info.
2074 kill_dead_locals();
2075
2076 // Now insert the uncommon trap subroutine call
2077 address call_addr = SharedRuntime::uncommon_trap_blob()->entry_point();
2078 const TypePtr* no_memory_effects = NULL;
2079 // Pass the index of the class to be loaded
2080 Node* call = make_runtime_call(RC_NO_LEAF | RC_UNCOMMON |
2081 (must_throw ? RC_MUST_THROW : 0),
2082 OptoRuntime::uncommon_trap_Type(),
2083 call_addr, "uncommon_trap", no_memory_effects,
2084 intcon(trap_request));
2085 assert(call->as_CallStaticJava()->uncommon_trap_request() == trap_request,
2086 "must extract request correctly from the graph");
2087 assert(trap_request != 0, "zero value reserved by uncommon_trap_request");
2088
2089 call->set_req(TypeFunc::ReturnAdr, returnadr());
2090 // The debug info is the only real input to this call.
2091
2092 // Halt-and-catch fire here. The above call should never return!
2093 HaltNode* halt = new HaltNode(control(), frameptr());
2094 _gvn.set_type_bottom(halt);
2095 root()->add_req(halt);
2096
2097 stop_and_kill_map();
2098 }
2099
2100
2101 //--------------------------just_allocated_object------------------------------
2102 // Report the object that was just allocated.
2103 // It must be the case that there are no intervening safepoints.
2104 // We use this to determine if an object is so "fresh" that
2105 // it does not require card marks.
2106 Node* GraphKit::just_allocated_object(Node* current_control) {
2107 if (C->recent_alloc_ctl() == current_control)
2108 return C->recent_alloc_obj();
2109 return NULL;
2110 }
2111
2112
2113 void GraphKit::round_double_arguments(ciMethod* dest_method) {
2114 // (Note: TypeFunc::make has a cache that makes this fast.)
2115 const TypeFunc* tf = TypeFunc::make(dest_method);
2116 int nargs = tf->domain()->cnt() - TypeFunc::Parms;
2117 for (int j = 0; j < nargs; j++) {
2118 const Type *targ = tf->domain()->field_at(j + TypeFunc::Parms);
2119 if( targ->basic_type() == T_DOUBLE ) {
2120 // If any parameters are doubles, they must be rounded before
2121 // the call, dstore_rounding does gvn.transform
2122 Node *arg = argument(j);
2123 arg = dstore_rounding(arg);
2124 set_argument(j, arg);
2125 }
2126 }
2127 }
2128
2129 /**
2130 * Record profiling data exact_kls for Node n with the type system so
2131 * that it can propagate it (speculation)
2132 *
2133 * @param n node that the type applies to
2134 * @param exact_kls type from profiling
2135 * @param maybe_null did profiling see null?
2136 *
2137 * @return node with improved type
2138 */
2139 Node* GraphKit::record_profile_for_speculation(Node* n, ciKlass* exact_kls, ProfilePtrKind ptr_kind) {
2140 const Type* current_type = _gvn.type(n);
2141 assert(UseTypeSpeculation, "type speculation must be on");
2142
2143 const TypePtr* speculative = current_type->speculative();
2144
2145 // Should the klass from the profile be recorded in the speculative type?
2146 if (current_type->would_improve_type(exact_kls, jvms()->depth())) {
2147 const TypeKlassPtr* tklass = TypeKlassPtr::make(exact_kls);
2148 const TypeOopPtr* xtype = tklass->as_instance_type();
2149 assert(xtype->klass_is_exact(), "Should be exact");
2150 // Any reason to believe n is not null (from this profiling or a previous one)?
2151 assert(ptr_kind != ProfileAlwaysNull, "impossible here");
2152 const TypePtr* ptr = (ptr_kind == ProfileMaybeNull && current_type->speculative_maybe_null()) ? TypePtr::BOTTOM : TypePtr::NOTNULL;
2153 // record the new speculative type's depth
2154 speculative = xtype->cast_to_ptr_type(ptr->ptr())->is_ptr();
2155 speculative = speculative->with_inline_depth(jvms()->depth());
2156 } else if (current_type->would_improve_ptr(ptr_kind)) {
2157 // Profiling report that null was never seen so we can change the
2158 // speculative type to non null ptr.
2159 if (ptr_kind == ProfileAlwaysNull) {
2160 speculative = TypePtr::NULL_PTR;
2161 } else {
2162 assert(ptr_kind == ProfileNeverNull, "nothing else is an improvement");
2163 const TypePtr* ptr = TypePtr::NOTNULL;
2164 if (speculative != NULL) {
2165 speculative = speculative->cast_to_ptr_type(ptr->ptr())->is_ptr();
2166 } else {
2167 speculative = ptr;
2168 }
2169 }
2170 }
2171
2172 if (speculative != current_type->speculative()) {
2173 // Build a type with a speculative type (what we think we know
2174 // about the type but will need a guard when we use it)
2175 const TypeOopPtr* spec_type = TypeOopPtr::make(TypePtr::BotPTR, Type::OffsetBot, TypeOopPtr::InstanceBot, speculative);
2176 // We're changing the type, we need a new CheckCast node to carry
2177 // the new type. The new type depends on the control: what
2178 // profiling tells us is only valid from here as far as we can
2179 // tell.
2180 Node* cast = new CheckCastPPNode(control(), n, current_type->remove_speculative()->join_speculative(spec_type));
2181 cast = _gvn.transform(cast);
2182 replace_in_map(n, cast);
2183 n = cast;
2184 }
2185
2186 return n;
2187 }
2188
2189 /**
2190 * Record profiling data from receiver profiling at an invoke with the
2191 * type system so that it can propagate it (speculation)
2192 *
2193 * @param n receiver node
2194 *
2195 * @return node with improved type
2196 */
2197 Node* GraphKit::record_profiled_receiver_for_speculation(Node* n) {
2198 if (!UseTypeSpeculation) {
2199 return n;
2200 }
2201 ciKlass* exact_kls = profile_has_unique_klass();
2202 ProfilePtrKind ptr_kind = ProfileMaybeNull;
2203 if ((java_bc() == Bytecodes::_checkcast ||
2204 java_bc() == Bytecodes::_instanceof ||
2205 java_bc() == Bytecodes::_aastore) &&
2206 method()->method_data()->is_mature()) {
2207 ciProfileData* data = method()->method_data()->bci_to_data(bci());
2208 if (data != NULL) {
2209 if (!data->as_BitData()->null_seen()) {
2210 ptr_kind = ProfileNeverNull;
2211 } else {
2212 assert(data->is_ReceiverTypeData(), "bad profile data type");
2213 ciReceiverTypeData* call = (ciReceiverTypeData*)data->as_ReceiverTypeData();
2214 uint i = 0;
2215 for (; i < call->row_limit(); i++) {
2216 ciKlass* receiver = call->receiver(i);
2217 if (receiver != NULL) {
2218 break;
2219 }
2220 }
2221 ptr_kind = (i == call->row_limit()) ? ProfileAlwaysNull : ProfileMaybeNull;
2222 }
2223 }
2224 }
2225 return record_profile_for_speculation(n, exact_kls, ptr_kind);
2226 }
2227
2228 /**
2229 * Record profiling data from argument profiling at an invoke with the
2230 * type system so that it can propagate it (speculation)
2231 *
2232 * @param dest_method target method for the call
2233 * @param bc what invoke bytecode is this?
2234 */
2235 void GraphKit::record_profiled_arguments_for_speculation(ciMethod* dest_method, Bytecodes::Code bc) {
2236 if (!UseTypeSpeculation) {
2237 return;
2238 }
2239 const TypeFunc* tf = TypeFunc::make(dest_method);
2240 int nargs = tf->domain()->cnt() - TypeFunc::Parms;
2241 int skip = Bytecodes::has_receiver(bc) ? 1 : 0;
2242 for (int j = skip, i = 0; j < nargs && i < TypeProfileArgsLimit; j++) {
2243 const Type *targ = tf->domain()->field_at(j + TypeFunc::Parms);
2244 if (targ->basic_type() == T_OBJECT || targ->basic_type() == T_ARRAY) {
2245 ProfilePtrKind ptr_kind = ProfileMaybeNull;
2246 ciKlass* better_type = NULL;
2247 if (method()->argument_profiled_type(bci(), i, better_type, ptr_kind)) {
2248 record_profile_for_speculation(argument(j), better_type, ptr_kind);
2249 }
2250 i++;
2251 }
2252 }
2253 }
2254
2255 /**
2256 * Record profiling data from parameter profiling at an invoke with
2257 * the type system so that it can propagate it (speculation)
2258 */
2259 void GraphKit::record_profiled_parameters_for_speculation() {
2260 if (!UseTypeSpeculation) {
2261 return;
2262 }
2263 for (int i = 0, j = 0; i < method()->arg_size() ; i++) {
2264 if (_gvn.type(local(i))->isa_oopptr()) {
2265 ProfilePtrKind ptr_kind = ProfileMaybeNull;
2266 ciKlass* better_type = NULL;
2267 if (method()->parameter_profiled_type(j, better_type, ptr_kind)) {
2268 record_profile_for_speculation(local(i), better_type, ptr_kind);
2269 }
2270 j++;
2271 }
2272 }
2273 }
2274
2275 /**
2276 * Record profiling data from return value profiling at an invoke with
2277 * the type system so that it can propagate it (speculation)
2278 */
2279 void GraphKit::record_profiled_return_for_speculation() {
2280 if (!UseTypeSpeculation) {
2281 return;
2282 }
2283 ProfilePtrKind ptr_kind = ProfileMaybeNull;
2284 ciKlass* better_type = NULL;
2285 if (method()->return_profiled_type(bci(), better_type, ptr_kind)) {
2286 // If profiling reports a single type for the return value,
2287 // feed it to the type system so it can propagate it as a
2288 // speculative type
2289 record_profile_for_speculation(stack(sp()-1), better_type, ptr_kind);
2290 }
2291 }
2292
2293 void GraphKit::round_double_result(ciMethod* dest_method) {
2294 // A non-strict method may return a double value which has an extended
2295 // exponent, but this must not be visible in a caller which is 'strict'
2296 // If a strict caller invokes a non-strict callee, round a double result
2297
2298 BasicType result_type = dest_method->return_type()->basic_type();
2299 assert( method() != NULL, "must have caller context");
2300 if( result_type == T_DOUBLE && method()->is_strict() && !dest_method->is_strict() ) {
2301 // Destination method's return value is on top of stack
2302 // dstore_rounding() does gvn.transform
2303 Node *result = pop_pair();
2304 result = dstore_rounding(result);
2305 push_pair(result);
2306 }
2307 }
2308
2309 // rounding for strict float precision conformance
2310 Node* GraphKit::precision_rounding(Node* n) {
2311 return UseStrictFP && _method->flags().is_strict()
2312 && UseSSE == 0 && Matcher::strict_fp_requires_explicit_rounding
2313 ? _gvn.transform( new RoundFloatNode(0, n) )
2314 : n;
2315 }
2316
2317 // rounding for strict double precision conformance
2318 Node* GraphKit::dprecision_rounding(Node *n) {
2319 return UseStrictFP && _method->flags().is_strict()
2320 && UseSSE <= 1 && Matcher::strict_fp_requires_explicit_rounding
2321 ? _gvn.transform( new RoundDoubleNode(0, n) )
2322 : n;
2323 }
2324
2325 // rounding for non-strict double stores
2326 Node* GraphKit::dstore_rounding(Node* n) {
2327 return Matcher::strict_fp_requires_explicit_rounding
2328 && UseSSE <= 1
2329 ? _gvn.transform( new RoundDoubleNode(0, n) )
2330 : n;
2331 }
2332
2333 //=============================================================================
2334 // Generate a fast path/slow path idiom. Graph looks like:
2335 // [foo] indicates that 'foo' is a parameter
2336 //
2337 // [in] NULL
2338 // \ /
2339 // CmpP
2340 // Bool ne
2341 // If
2342 // / \
2343 // True False-<2>
2344 // / |
2345 // / cast_not_null
2346 // Load | | ^
2347 // [fast_test] | |
2348 // gvn to opt_test | |
2349 // / \ | <1>
2350 // True False |
2351 // | \\ |
2352 // [slow_call] \[fast_result]
2353 // Ctl Val \ \
2354 // | \ \
2355 // Catch <1> \ \
2356 // / \ ^ \ \
2357 // Ex No_Ex | \ \
2358 // | \ \ | \ <2> \
2359 // ... \ [slow_res] | | \ [null_result]
2360 // \ \--+--+--- | |
2361 // \ | / \ | /
2362 // --------Region Phi
2363 //
2364 //=============================================================================
2365 // Code is structured as a series of driver functions all called 'do_XXX' that
2366 // call a set of helper functions. Helper functions first, then drivers.
2367
2368 //------------------------------null_check_oop---------------------------------
2369 // Null check oop. Set null-path control into Region in slot 3.
2370 // Make a cast-not-nullness use the other not-null control. Return cast.
2371 Node* GraphKit::null_check_oop(Node* value, Node* *null_control,
2372 bool never_see_null,
2373 bool safe_for_replace,
2374 bool speculative) {
2375 // Initial NULL check taken path
2376 (*null_control) = top();
2377 Node* cast = null_check_common(value, T_OBJECT, false, null_control, speculative);
2378
2379 // Generate uncommon_trap:
2380 if (never_see_null && (*null_control) != top()) {
2381 // If we see an unexpected null at a check-cast we record it and force a
2382 // recompile; the offending check-cast will be compiled to handle NULLs.
2383 // If we see more than one offending BCI, then all checkcasts in the
2384 // method will be compiled to handle NULLs.
2385 PreserveJVMState pjvms(this);
2386 set_control(*null_control);
2387 replace_in_map(value, null());
2388 Deoptimization::DeoptReason reason = Deoptimization::reason_null_check(speculative);
2389 uncommon_trap(reason,
2390 Deoptimization::Action_make_not_entrant);
2391 (*null_control) = top(); // NULL path is dead
2392 }
2393 if ((*null_control) == top() && safe_for_replace) {
2394 replace_in_map(value, cast);
2395 }
2396
2397 // Cast away null-ness on the result
2398 return cast;
2399 }
2400
2401 //------------------------------opt_iff----------------------------------------
2402 // Optimize the fast-check IfNode. Set the fast-path region slot 2.
2403 // Return slow-path control.
2404 Node* GraphKit::opt_iff(Node* region, Node* iff) {
2405 IfNode *opt_iff = _gvn.transform(iff)->as_If();
2406
2407 // Fast path taken; set region slot 2
2408 Node *fast_taken = _gvn.transform( new IfFalseNode(opt_iff) );
2409 region->init_req(2,fast_taken); // Capture fast-control
2410
2411 // Fast path not-taken, i.e. slow path
2412 Node *slow_taken = _gvn.transform( new IfTrueNode(opt_iff) );
2413 return slow_taken;
2414 }
2415
2416 //-----------------------------make_runtime_call-------------------------------
2417 Node* GraphKit::make_runtime_call(int flags,
2418 const TypeFunc* call_type, address call_addr,
2419 const char* call_name,
2420 const TypePtr* adr_type,
2421 // The following parms are all optional.
2422 // The first NULL ends the list.
2423 Node* parm0, Node* parm1,
2424 Node* parm2, Node* parm3,
2425 Node* parm4, Node* parm5,
2426 Node* parm6, Node* parm7) {
2427 // Slow-path call
2428 bool is_leaf = !(flags & RC_NO_LEAF);
2429 bool has_io = (!is_leaf && !(flags & RC_NO_IO));
2430 if (call_name == NULL) {
2431 assert(!is_leaf, "must supply name for leaf");
2432 call_name = OptoRuntime::stub_name(call_addr);
2433 }
2434 CallNode* call;
2435 if (!is_leaf) {
2436 call = new CallStaticJavaNode(call_type, call_addr, call_name,
2437 bci(), adr_type);
2438 } else if (flags & RC_NO_FP) {
2439 call = new CallLeafNoFPNode(call_type, call_addr, call_name, adr_type);
2440 } else {
2441 call = new CallLeafNode(call_type, call_addr, call_name, adr_type);
2442 }
2443
2444 // The following is similar to set_edges_for_java_call,
2445 // except that the memory effects of the call are restricted to AliasIdxRaw.
2446
2447 // Slow path call has no side-effects, uses few values
2448 bool wide_in = !(flags & RC_NARROW_MEM);
2449 bool wide_out = (C->get_alias_index(adr_type) == Compile::AliasIdxBot);
2450
2451 Node* prev_mem = NULL;
2452 if (wide_in) {
2453 prev_mem = set_predefined_input_for_runtime_call(call);
2454 } else {
2455 assert(!wide_out, "narrow in => narrow out");
2456 Node* narrow_mem = memory(adr_type);
2457 prev_mem = reset_memory();
2458 map()->set_memory(narrow_mem);
2459 set_predefined_input_for_runtime_call(call);
2460 }
2461
2462 // Hook each parm in order. Stop looking at the first NULL.
2463 if (parm0 != NULL) { call->init_req(TypeFunc::Parms+0, parm0);
2464 if (parm1 != NULL) { call->init_req(TypeFunc::Parms+1, parm1);
2465 if (parm2 != NULL) { call->init_req(TypeFunc::Parms+2, parm2);
2466 if (parm3 != NULL) { call->init_req(TypeFunc::Parms+3, parm3);
2467 if (parm4 != NULL) { call->init_req(TypeFunc::Parms+4, parm4);
2468 if (parm5 != NULL) { call->init_req(TypeFunc::Parms+5, parm5);
2469 if (parm6 != NULL) { call->init_req(TypeFunc::Parms+6, parm6);
2470 if (parm7 != NULL) { call->init_req(TypeFunc::Parms+7, parm7);
2471 /* close each nested if ===> */ } } } } } } } }
2472 assert(call->in(call->req()-1) != NULL, "must initialize all parms");
2473
2474 if (!is_leaf) {
2475 // Non-leaves can block and take safepoints:
2476 add_safepoint_edges(call, ((flags & RC_MUST_THROW) != 0));
2477 }
2478 // Non-leaves can throw exceptions:
2479 if (has_io) {
2480 call->set_req(TypeFunc::I_O, i_o());
2481 }
2482
2483 if (flags & RC_UNCOMMON) {
2484 // Set the count to a tiny probability. Cf. Estimate_Block_Frequency.
2485 // (An "if" probability corresponds roughly to an unconditional count.
2486 // Sort of.)
2487 call->set_cnt(PROB_UNLIKELY_MAG(4));
2488 }
2489
2490 Node* c = _gvn.transform(call);
2491 assert(c == call, "cannot disappear");
2492
2493 if (wide_out) {
2494 // Slow path call has full side-effects.
2495 set_predefined_output_for_runtime_call(call);
2496 } else {
2497 // Slow path call has few side-effects, and/or sets few values.
2498 set_predefined_output_for_runtime_call(call, prev_mem, adr_type);
2499 }
2500
2501 if (has_io) {
2502 set_i_o(_gvn.transform(new ProjNode(call, TypeFunc::I_O)));
2503 }
2504 return call;
2505
2506 }
2507
2508 //------------------------------merge_memory-----------------------------------
2509 // Merge memory from one path into the current memory state.
2510 void GraphKit::merge_memory(Node* new_mem, Node* region, int new_path) {
2511 for (MergeMemStream mms(merged_memory(), new_mem->as_MergeMem()); mms.next_non_empty2(); ) {
2512 Node* old_slice = mms.force_memory();
2513 Node* new_slice = mms.memory2();
2514 if (old_slice != new_slice) {
2515 PhiNode* phi;
2516 if (old_slice->is_Phi() && old_slice->as_Phi()->region() == region) {
2517 if (mms.is_empty()) {
2518 // clone base memory Phi's inputs for this memory slice
2519 assert(old_slice == mms.base_memory(), "sanity");
2520 phi = PhiNode::make(region, NULL, Type::MEMORY, mms.adr_type(C));
2521 _gvn.set_type(phi, Type::MEMORY);
2522 for (uint i = 1; i < phi->req(); i++) {
2523 phi->init_req(i, old_slice->in(i));
2524 }
2525 } else {
2526 phi = old_slice->as_Phi(); // Phi was generated already
2527 }
2528 } else {
2529 phi = PhiNode::make(region, old_slice, Type::MEMORY, mms.adr_type(C));
2530 _gvn.set_type(phi, Type::MEMORY);
2531 }
2532 phi->set_req(new_path, new_slice);
2533 mms.set_memory(phi);
2534 }
2535 }
2536 }
2537
2538 //------------------------------make_slow_call_ex------------------------------
2539 // Make the exception handler hookups for the slow call
2540 void GraphKit::make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj, bool deoptimize) {
2541 if (stopped()) return;
2542
2543 // Make a catch node with just two handlers: fall-through and catch-all
2544 Node* i_o = _gvn.transform( new ProjNode(call, TypeFunc::I_O, separate_io_proj) );
2545 Node* catc = _gvn.transform( new CatchNode(control(), i_o, 2) );
2546 Node* norm = _gvn.transform( new CatchProjNode(catc, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci) );
2547 Node* excp = _gvn.transform( new CatchProjNode(catc, CatchProjNode::catch_all_index, CatchProjNode::no_handler_bci) );
2548
2549 { PreserveJVMState pjvms(this);
2550 set_control(excp);
2551 set_i_o(i_o);
2552
2553 if (excp != top()) {
2554 if (deoptimize) {
2555 // Deoptimize if an exception is caught. Don't construct exception state in this case.
2556 uncommon_trap(Deoptimization::Reason_unhandled,
2557 Deoptimization::Action_none);
2558 } else {
2559 // Create an exception state also.
2560 // Use an exact type if the caller has specified a specific exception.
2561 const Type* ex_type = TypeOopPtr::make_from_klass_unique(ex_klass)->cast_to_ptr_type(TypePtr::NotNull);
2562 Node* ex_oop = new CreateExNode(ex_type, control(), i_o);
2563 add_exception_state(make_exception_state(_gvn.transform(ex_oop)));
2564 }
2565 }
2566 }
2567
2568 // Get the no-exception control from the CatchNode.
2569 set_control(norm);
2570 }
2571
2572 static IfNode* gen_subtype_check_compare(Node* ctrl, Node* in1, Node* in2, BoolTest::mask test, float p, PhaseGVN* gvn, BasicType bt) {
2573 Node* cmp = NULL;
2574 switch(bt) {
2575 case T_INT: cmp = new CmpINode(in1, in2); break;
2576 case T_ADDRESS: cmp = new CmpPNode(in1, in2); break;
2577 default: fatal("unexpected comparison type %s", type2name(bt));
2578 }
2579 gvn->transform(cmp);
2580 Node* bol = gvn->transform(new BoolNode(cmp, test));
2581 IfNode* iff = new IfNode(ctrl, bol, p, COUNT_UNKNOWN);
2582 gvn->transform(iff);
2583 if (!bol->is_Con()) gvn->record_for_igvn(iff);
2584 return iff;
2585 }
2586
2587
2588 //-------------------------------gen_subtype_check-----------------------------
2589 // Generate a subtyping check. Takes as input the subtype and supertype.
2590 // Returns 2 values: sets the default control() to the true path and returns
2591 // the false path. Only reads invariant memory; sets no (visible) memory.
2592 // The PartialSubtypeCheckNode sets the hidden 1-word cache in the encoding
2593 // but that's not exposed to the optimizer. This call also doesn't take in an
2594 // Object; if you wish to check an Object you need to load the Object's class
2595 // prior to coming here.
2596 Node* Phase::gen_subtype_check(Node* subklass, Node* superklass, Node** ctrl, MergeMemNode* mem, PhaseGVN* gvn) {
2597 Compile* C = gvn->C;
2598
2599 if ((*ctrl)->is_top()) {
2600 return C->top();
2601 }
2602
2603 // Fast check for identical types, perhaps identical constants.
2604 // The types can even be identical non-constants, in cases
2605 // involving Array.newInstance, Object.clone, etc.
2606 if (subklass == superklass)
2607 return C->top(); // false path is dead; no test needed.
2608
2609 if (gvn->type(superklass)->singleton()) {
2610 ciKlass* superk = gvn->type(superklass)->is_klassptr()->klass();
2611 ciKlass* subk = gvn->type(subklass)->is_klassptr()->klass();
2612
2613 // In the common case of an exact superklass, try to fold up the
2614 // test before generating code. You may ask, why not just generate
2615 // the code and then let it fold up? The answer is that the generated
2616 // code will necessarily include null checks, which do not always
2617 // completely fold away. If they are also needless, then they turn
2618 // into a performance loss. Example:
2619 // Foo[] fa = blah(); Foo x = fa[0]; fa[1] = x;
2620 // Here, the type of 'fa' is often exact, so the store check
2621 // of fa[1]=x will fold up, without testing the nullness of x.
2622 switch (C->static_subtype_check(superk, subk)) {
2623 case Compile::SSC_always_false:
2624 {
2625 Node* always_fail = *ctrl;
2626 *ctrl = gvn->C->top();
2627 return always_fail;
2628 }
2629 case Compile::SSC_always_true:
2630 return C->top();
2631 case Compile::SSC_easy_test:
2632 {
2633 // Just do a direct pointer compare and be done.
2634 IfNode* iff = gen_subtype_check_compare(*ctrl, subklass, superklass, BoolTest::eq, PROB_STATIC_FREQUENT, gvn, T_ADDRESS);
2635 *ctrl = gvn->transform(new IfTrueNode(iff));
2636 return gvn->transform(new IfFalseNode(iff));
2637 }
2638 case Compile::SSC_full_test:
2639 break;
2640 default:
2641 ShouldNotReachHere();
2642 }
2643 }
2644
2645 // %%% Possible further optimization: Even if the superklass is not exact,
2646 // if the subklass is the unique subtype of the superklass, the check
2647 // will always succeed. We could leave a dependency behind to ensure this.
2648
2649 // First load the super-klass's check-offset
2650 Node *p1 = gvn->transform(new AddPNode(superklass, superklass, gvn->MakeConX(in_bytes(Klass::super_check_offset_offset()))));
2651 Node* m = mem->memory_at(C->get_alias_index(gvn->type(p1)->is_ptr()));
2652 Node *chk_off = gvn->transform(new LoadINode(NULL, m, p1, gvn->type(p1)->is_ptr(), TypeInt::INT, MemNode::unordered));
2653 int cacheoff_con = in_bytes(Klass::secondary_super_cache_offset());
2654 bool might_be_cache = (gvn->find_int_con(chk_off, cacheoff_con) == cacheoff_con);
2655
2656 // Load from the sub-klass's super-class display list, or a 1-word cache of
2657 // the secondary superclass list, or a failing value with a sentinel offset
2658 // if the super-klass is an interface or exceptionally deep in the Java
2659 // hierarchy and we have to scan the secondary superclass list the hard way.
2660 // Worst-case type is a little odd: NULL is allowed as a result (usually
2661 // klass loads can never produce a NULL).
2662 Node *chk_off_X = chk_off;
2663 #ifdef _LP64
2664 chk_off_X = gvn->transform(new ConvI2LNode(chk_off_X));
2665 #endif
2666 Node *p2 = gvn->transform(new AddPNode(subklass,subklass,chk_off_X));
2667 // For some types like interfaces the following loadKlass is from a 1-word
2668 // cache which is mutable so can't use immutable memory. Other
2669 // types load from the super-class display table which is immutable.
2670 m = mem->memory_at(C->get_alias_index(gvn->type(p2)->is_ptr()));
2671 Node *kmem = might_be_cache ? m : C->immutable_memory();
2672 Node *nkls = gvn->transform(LoadKlassNode::make(*gvn, NULL, kmem, p2, gvn->type(p2)->is_ptr(), TypeKlassPtr::OBJECT_OR_NULL));
2673
2674 // Compile speed common case: ARE a subtype and we canNOT fail
2675 if( superklass == nkls )
2676 return C->top(); // false path is dead; no test needed.
2677
2678 // See if we get an immediate positive hit. Happens roughly 83% of the
2679 // time. Test to see if the value loaded just previously from the subklass
2680 // is exactly the superklass.
2681 IfNode *iff1 = gen_subtype_check_compare(*ctrl, superklass, nkls, BoolTest::eq, PROB_LIKELY(0.83f), gvn, T_ADDRESS);
2682 Node *iftrue1 = gvn->transform( new IfTrueNode (iff1));
2683 *ctrl = gvn->transform(new IfFalseNode(iff1));
2684
2685 // Compile speed common case: Check for being deterministic right now. If
2686 // chk_off is a constant and not equal to cacheoff then we are NOT a
2687 // subklass. In this case we need exactly the 1 test above and we can
2688 // return those results immediately.
2689 if (!might_be_cache) {
2690 Node* not_subtype_ctrl = *ctrl;
2691 *ctrl = iftrue1; // We need exactly the 1 test above
2692 return not_subtype_ctrl;
2693 }
2694
2695 // Gather the various success & failures here
2696 RegionNode *r_ok_subtype = new RegionNode(4);
2697 gvn->record_for_igvn(r_ok_subtype);
2698 RegionNode *r_not_subtype = new RegionNode(3);
2699 gvn->record_for_igvn(r_not_subtype);
2700
2701 r_ok_subtype->init_req(1, iftrue1);
2702
2703 // Check for immediate negative hit. Happens roughly 11% of the time (which
2704 // is roughly 63% of the remaining cases). Test to see if the loaded
2705 // check-offset points into the subklass display list or the 1-element
2706 // cache. If it points to the display (and NOT the cache) and the display
2707 // missed then it's not a subtype.
2708 Node *cacheoff = gvn->intcon(cacheoff_con);
2709 IfNode *iff2 = gen_subtype_check_compare(*ctrl, chk_off, cacheoff, BoolTest::ne, PROB_LIKELY(0.63f), gvn, T_INT);
2710 r_not_subtype->init_req(1, gvn->transform(new IfTrueNode (iff2)));
2711 *ctrl = gvn->transform(new IfFalseNode(iff2));
2712
2713 // Check for self. Very rare to get here, but it is taken 1/3 the time.
2714 // No performance impact (too rare) but allows sharing of secondary arrays
2715 // which has some footprint reduction.
2716 IfNode *iff3 = gen_subtype_check_compare(*ctrl, subklass, superklass, BoolTest::eq, PROB_LIKELY(0.36f), gvn, T_ADDRESS);
2717 r_ok_subtype->init_req(2, gvn->transform(new IfTrueNode(iff3)));
2718 *ctrl = gvn->transform(new IfFalseNode(iff3));
2719
2720 // -- Roads not taken here: --
2721 // We could also have chosen to perform the self-check at the beginning
2722 // of this code sequence, as the assembler does. This would not pay off
2723 // the same way, since the optimizer, unlike the assembler, can perform
2724 // static type analysis to fold away many successful self-checks.
2725 // Non-foldable self checks work better here in second position, because
2726 // the initial primary superclass check subsumes a self-check for most
2727 // types. An exception would be a secondary type like array-of-interface,
2728 // which does not appear in its own primary supertype display.
2729 // Finally, we could have chosen to move the self-check into the
2730 // PartialSubtypeCheckNode, and from there out-of-line in a platform
2731 // dependent manner. But it is worthwhile to have the check here,
2732 // where it can be perhaps be optimized. The cost in code space is
2733 // small (register compare, branch).
2734
2735 // Now do a linear scan of the secondary super-klass array. Again, no real
2736 // performance impact (too rare) but it's gotta be done.
2737 // Since the code is rarely used, there is no penalty for moving it
2738 // out of line, and it can only improve I-cache density.
2739 // The decision to inline or out-of-line this final check is platform
2740 // dependent, and is found in the AD file definition of PartialSubtypeCheck.
2741 Node* psc = gvn->transform(
2742 new PartialSubtypeCheckNode(*ctrl, subklass, superklass));
2743
2744 IfNode *iff4 = gen_subtype_check_compare(*ctrl, psc, gvn->zerocon(T_OBJECT), BoolTest::ne, PROB_FAIR, gvn, T_ADDRESS);
2745 r_not_subtype->init_req(2, gvn->transform(new IfTrueNode (iff4)));
2746 r_ok_subtype ->init_req(3, gvn->transform(new IfFalseNode(iff4)));
2747
2748 // Return false path; set default control to true path.
2749 *ctrl = gvn->transform(r_ok_subtype);
2750 return gvn->transform(r_not_subtype);
2751 }
2752
2753 // Profile-driven exact type check:
2754 Node* GraphKit::type_check_receiver(Node* receiver, ciKlass* klass,
2755 float prob,
2756 Node* *casted_receiver) {
2757 const TypeKlassPtr* tklass = TypeKlassPtr::make(klass);
2758 Node* recv_klass = load_object_klass(receiver);
2759 Node* want_klass = makecon(tklass);
2760 Node* cmp = _gvn.transform( new CmpPNode(recv_klass, want_klass) );
2761 Node* bol = _gvn.transform( new BoolNode(cmp, BoolTest::eq) );
2762 IfNode* iff = create_and_xform_if(control(), bol, prob, COUNT_UNKNOWN);
2763 set_control( _gvn.transform( new IfTrueNode (iff) ));
2764 Node* fail = _gvn.transform( new IfFalseNode(iff) );
2765
2766 const TypeOopPtr* recv_xtype = tklass->as_instance_type();
2767 assert(recv_xtype->klass_is_exact(), "");
2768
2769 // Subsume downstream occurrences of receiver with a cast to
2770 // recv_xtype, since now we know what the type will be.
2771 Node* cast = new CheckCastPPNode(control(), receiver, recv_xtype);
2772 (*casted_receiver) = _gvn.transform(cast);
2773 // (User must make the replace_in_map call.)
2774
2775 return fail;
2776 }
2777
2778
2779 //------------------------------seems_never_null-------------------------------
2780 // Use null_seen information if it is available from the profile.
2781 // If we see an unexpected null at a type check we record it and force a
2782 // recompile; the offending check will be recompiled to handle NULLs.
2783 // If we see several offending BCIs, then all checks in the
2784 // method will be recompiled.
2785 bool GraphKit::seems_never_null(Node* obj, ciProfileData* data, bool& speculating) {
2786 speculating = !_gvn.type(obj)->speculative_maybe_null();
2787 Deoptimization::DeoptReason reason = Deoptimization::reason_null_check(speculating);
2788 if (UncommonNullCast // Cutout for this technique
2789 && obj != null() // And not the -Xcomp stupid case?
2790 && !too_many_traps(reason)
2791 ) {
2792 if (speculating) {
2793 return true;
2794 }
2795 if (data == NULL)
2796 // Edge case: no mature data. Be optimistic here.
2797 return true;
2798 // If the profile has not seen a null, assume it won't happen.
2799 assert(java_bc() == Bytecodes::_checkcast ||
2800 java_bc() == Bytecodes::_instanceof ||
2801 java_bc() == Bytecodes::_aastore, "MDO must collect null_seen bit here");
2802 return !data->as_BitData()->null_seen();
2803 }
2804 speculating = false;
2805 return false;
2806 }
2807
2808 //------------------------maybe_cast_profiled_receiver-------------------------
2809 // If the profile has seen exactly one type, narrow to exactly that type.
2810 // Subsequent type checks will always fold up.
2811 Node* GraphKit::maybe_cast_profiled_receiver(Node* not_null_obj,
2812 ciKlass* require_klass,
2813 ciKlass* spec_klass,
2814 bool safe_for_replace) {
2815 if (!UseTypeProfile || !TypeProfileCasts) return NULL;
2816
2817 Deoptimization::DeoptReason reason = Deoptimization::reason_class_check(spec_klass != NULL);
2818
2819 // Make sure we haven't already deoptimized from this tactic.
2820 if (too_many_traps(reason) || too_many_recompiles(reason))
2821 return NULL;
2822
2823 // (No, this isn't a call, but it's enough like a virtual call
2824 // to use the same ciMethod accessor to get the profile info...)
2825 // If we have a speculative type use it instead of profiling (which
2826 // may not help us)
2827 ciKlass* exact_kls = spec_klass == NULL ? profile_has_unique_klass() : spec_klass;
2828 if (exact_kls != NULL) {// no cast failures here
2829 if (require_klass == NULL ||
2830 C->static_subtype_check(require_klass, exact_kls) == Compile::SSC_always_true) {
2831 // If we narrow the type to match what the type profile sees or
2832 // the speculative type, we can then remove the rest of the
2833 // cast.
2834 // This is a win, even if the exact_kls is very specific,
2835 // because downstream operations, such as method calls,
2836 // will often benefit from the sharper type.
2837 Node* exact_obj = not_null_obj; // will get updated in place...
2838 Node* slow_ctl = type_check_receiver(exact_obj, exact_kls, 1.0,
2839 &exact_obj);
2840 { PreserveJVMState pjvms(this);
2841 set_control(slow_ctl);
2842 uncommon_trap_exact(reason, Deoptimization::Action_maybe_recompile);
2843 }
2844 if (safe_for_replace) {
2845 replace_in_map(not_null_obj, exact_obj);
2846 }
2847 return exact_obj;
2848 }
2849 // assert(ssc == Compile::SSC_always_true)... except maybe the profile lied to us.
2850 }
2851
2852 return NULL;
2853 }
2854
2855 /**
2856 * Cast obj to type and emit guard unless we had too many traps here
2857 * already
2858 *
2859 * @param obj node being casted
2860 * @param type type to cast the node to
2861 * @param not_null true if we know node cannot be null
2862 */
2863 Node* GraphKit::maybe_cast_profiled_obj(Node* obj,
2864 ciKlass* type,
2865 bool not_null) {
2866 if (stopped()) {
2867 return obj;
2868 }
2869
2870 // type == NULL if profiling tells us this object is always null
2871 if (type != NULL) {
2872 Deoptimization::DeoptReason class_reason = Deoptimization::Reason_speculate_class_check;
2873 Deoptimization::DeoptReason null_reason = Deoptimization::Reason_speculate_null_check;
2874
2875 if (!too_many_traps(null_reason) && !too_many_recompiles(null_reason) &&
2876 !too_many_traps(class_reason) &&
2877 !too_many_recompiles(class_reason)) {
2878 Node* not_null_obj = NULL;
2879 // not_null is true if we know the object is not null and
2880 // there's no need for a null check
2881 if (!not_null) {
2882 Node* null_ctl = top();
2883 not_null_obj = null_check_oop(obj, &null_ctl, true, true, true);
2884 assert(null_ctl->is_top(), "no null control here");
2885 } else {
2886 not_null_obj = obj;
2887 }
2888
2889 Node* exact_obj = not_null_obj;
2890 ciKlass* exact_kls = type;
2891 Node* slow_ctl = type_check_receiver(exact_obj, exact_kls, 1.0,
2892 &exact_obj);
2893 {
2894 PreserveJVMState pjvms(this);
2895 set_control(slow_ctl);
2896 uncommon_trap_exact(class_reason, Deoptimization::Action_maybe_recompile);
2897 }
2898 replace_in_map(not_null_obj, exact_obj);
2899 obj = exact_obj;
2900 }
2901 } else {
2902 if (!too_many_traps(Deoptimization::Reason_null_assert) &&
2903 !too_many_recompiles(Deoptimization::Reason_null_assert)) {
2904 Node* exact_obj = null_assert(obj);
2905 replace_in_map(obj, exact_obj);
2906 obj = exact_obj;
2907 }
2908 }
2909 return obj;
2910 }
2911
2912 //-------------------------------gen_instanceof--------------------------------
2913 // Generate an instance-of idiom. Used by both the instance-of bytecode
2914 // and the reflective instance-of call.
2915 Node* GraphKit::gen_instanceof(Node* obj, Node* superklass, bool safe_for_replace) {
2916 kill_dead_locals(); // Benefit all the uncommon traps
2917 assert( !stopped(), "dead parse path should be checked in callers" );
2918 assert(!TypePtr::NULL_PTR->higher_equal(_gvn.type(superklass)->is_klassptr()),
2919 "must check for not-null not-dead klass in callers");
2920
2921 // Make the merge point
2922 enum { _obj_path = 1, _fail_path, _null_path, PATH_LIMIT };
2923 RegionNode* region = new RegionNode(PATH_LIMIT);
2924 Node* phi = new PhiNode(region, TypeInt::BOOL);
2925 C->set_has_split_ifs(true); // Has chance for split-if optimization
2926
2927 ciProfileData* data = NULL;
2928 if (java_bc() == Bytecodes::_instanceof) { // Only for the bytecode
2929 data = method()->method_data()->bci_to_data(bci());
2930 }
2931 bool speculative_not_null = false;
2932 bool never_see_null = (ProfileDynamicTypes // aggressive use of profile
2933 && seems_never_null(obj, data, speculative_not_null));
2934
2935 // Null check; get casted pointer; set region slot 3
2936 Node* null_ctl = top();
2937 Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace, speculative_not_null);
2938
2939 // If not_null_obj is dead, only null-path is taken
2940 if (stopped()) { // Doing instance-of on a NULL?
2941 set_control(null_ctl);
2942 return intcon(0);
2943 }
2944 region->init_req(_null_path, null_ctl);
2945 phi ->init_req(_null_path, intcon(0)); // Set null path value
2946 if (null_ctl == top()) {
2947 // Do this eagerly, so that pattern matches like is_diamond_phi
2948 // will work even during parsing.
2949 assert(_null_path == PATH_LIMIT-1, "delete last");
2950 region->del_req(_null_path);
2951 phi ->del_req(_null_path);
2952 }
2953
2954 // Do we know the type check always succeed?
2955 bool known_statically = false;
2956 if (_gvn.type(superklass)->singleton()) {
2957 ciKlass* superk = _gvn.type(superklass)->is_klassptr()->klass();
2958 ciKlass* subk = _gvn.type(obj)->is_oopptr()->klass();
2959 if (subk != NULL && subk->is_loaded()) {
2960 int static_res = C->static_subtype_check(superk, subk);
2961 known_statically = (static_res == Compile::SSC_always_true || static_res == Compile::SSC_always_false);
2962 }
2963 }
2964
2965 if (!known_statically) {
2966 const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
2967 // We may not have profiling here or it may not help us. If we
2968 // have a speculative type use it to perform an exact cast.
2969 ciKlass* spec_obj_type = obj_type->speculative_type();
2970 if (spec_obj_type != NULL || (ProfileDynamicTypes && data != NULL)) {
2971 Node* cast_obj = maybe_cast_profiled_receiver(not_null_obj, NULL, spec_obj_type, safe_for_replace);
2972 if (stopped()) { // Profile disagrees with this path.
2973 set_control(null_ctl); // Null is the only remaining possibility.
2974 return intcon(0);
2975 }
2976 if (cast_obj != NULL) {
2977 not_null_obj = cast_obj;
2978 }
2979 }
2980 }
2981
2982 // Load the object's klass
2983 Node* obj_klass = load_object_klass(not_null_obj);
2984
2985 // Generate the subtype check
2986 Node* not_subtype_ctrl = gen_subtype_check(obj_klass, superklass);
2987
2988 // Plug in the success path to the general merge in slot 1.
2989 region->init_req(_obj_path, control());
2990 phi ->init_req(_obj_path, intcon(1));
2991
2992 // Plug in the failing path to the general merge in slot 2.
2993 region->init_req(_fail_path, not_subtype_ctrl);
2994 phi ->init_req(_fail_path, intcon(0));
2995
2996 // Return final merged results
2997 set_control( _gvn.transform(region) );
2998 record_for_igvn(region);
2999
3000 // If we know the type check always succeeds then we don't use the
3001 // profiling data at this bytecode. Don't lose it, feed it to the
3002 // type system as a speculative type.
3003 if (safe_for_replace) {
3004 Node* casted_obj = record_profiled_receiver_for_speculation(obj);
3005 replace_in_map(obj, casted_obj);
3006 }
3007
3008 return _gvn.transform(phi);
3009 }
3010
3011 //-------------------------------gen_checkcast---------------------------------
3012 // Generate a checkcast idiom. Used by both the checkcast bytecode and the
3013 // array store bytecode. Stack must be as-if BEFORE doing the bytecode so the
3014 // uncommon-trap paths work. Adjust stack after this call.
3015 // If failure_control is supplied and not null, it is filled in with
3016 // the control edge for the cast failure. Otherwise, an appropriate
3017 // uncommon trap or exception is thrown.
3018 Node* GraphKit::gen_checkcast(Node *obj, Node* superklass,
3019 Node* *failure_control) {
3020 kill_dead_locals(); // Benefit all the uncommon traps
3021 const TypeKlassPtr *tk = _gvn.type(superklass)->is_klassptr();
3022 const Type *toop = TypeOopPtr::make_from_klass(tk->klass());
3023
3024 // Fast cutout: Check the case that the cast is vacuously true.
3025 // This detects the common cases where the test will short-circuit
3026 // away completely. We do this before we perform the null check,
3027 // because if the test is going to turn into zero code, we don't
3028 // want a residual null check left around. (Causes a slowdown,
3029 // for example, in some objArray manipulations, such as a[i]=a[j].)
3030 if (tk->singleton()) {
3031 const TypeOopPtr* objtp = _gvn.type(obj)->isa_oopptr();
3032 if (objtp != NULL && objtp->klass() != NULL) {
3033 switch (C->static_subtype_check(tk->klass(), objtp->klass())) {
3034 case Compile::SSC_always_true:
3035 // If we know the type check always succeed then we don't use
3036 // the profiling data at this bytecode. Don't lose it, feed it
3037 // to the type system as a speculative type.
3038 return record_profiled_receiver_for_speculation(obj);
3039 case Compile::SSC_always_false:
3040 // It needs a null check because a null will *pass* the cast check.
3041 // A non-null value will always produce an exception.
3042 return null_assert(obj);
3043 }
3044 }
3045 }
3046
3047 ciProfileData* data = NULL;
3048 bool safe_for_replace = false;
3049 if (failure_control == NULL) { // use MDO in regular case only
3050 assert(java_bc() == Bytecodes::_aastore ||
3051 java_bc() == Bytecodes::_checkcast,
3052 "interpreter profiles type checks only for these BCs");
3053 data = method()->method_data()->bci_to_data(bci());
3054 safe_for_replace = true;
3055 }
3056
3057 // Make the merge point
3058 enum { _obj_path = 1, _null_path, PATH_LIMIT };
3059 RegionNode* region = new RegionNode(PATH_LIMIT);
3060 Node* phi = new PhiNode(region, toop);
3061 C->set_has_split_ifs(true); // Has chance for split-if optimization
3062
3063 // Use null-cast information if it is available
3064 bool speculative_not_null = false;
3065 bool never_see_null = ((failure_control == NULL) // regular case only
3066 && seems_never_null(obj, data, speculative_not_null));
3067
3068 // Null check; get casted pointer; set region slot 3
3069 Node* null_ctl = top();
3070 Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace, speculative_not_null);
3071
3072 // If not_null_obj is dead, only null-path is taken
3073 if (stopped()) { // Doing instance-of on a NULL?
3074 set_control(null_ctl);
3075 return null();
3076 }
3077 region->init_req(_null_path, null_ctl);
3078 phi ->init_req(_null_path, null()); // Set null path value
3079 if (null_ctl == top()) {
3080 // Do this eagerly, so that pattern matches like is_diamond_phi
3081 // will work even during parsing.
3082 assert(_null_path == PATH_LIMIT-1, "delete last");
3083 region->del_req(_null_path);
3084 phi ->del_req(_null_path);
3085 }
3086
3087 Node* cast_obj = NULL;
3088 if (tk->klass_is_exact()) {
3089 // The following optimization tries to statically cast the speculative type of the object
3090 // (for example obtained during profiling) to the type of the superklass and then do a
3091 // dynamic check that the type of the object is what we expect. To work correctly
3092 // for checkcast and aastore the type of superklass should be exact.
3093 const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
3094 // We may not have profiling here or it may not help us. If we have
3095 // a speculative type use it to perform an exact cast.
3096 ciKlass* spec_obj_type = obj_type->speculative_type();
3097 if (spec_obj_type != NULL || data != NULL) {
3098 cast_obj = maybe_cast_profiled_receiver(not_null_obj, tk->klass(), spec_obj_type, safe_for_replace);
3099 if (cast_obj != NULL) {
3100 if (failure_control != NULL) // failure is now impossible
3101 (*failure_control) = top();
3102 // adjust the type of the phi to the exact klass:
3103 phi->raise_bottom_type(_gvn.type(cast_obj)->meet_speculative(TypePtr::NULL_PTR));
3104 }
3105 }
3106 }
3107
3108 if (cast_obj == NULL) {
3109 // Load the object's klass
3110 Node* obj_klass = load_object_klass(not_null_obj);
3111
3112 // Generate the subtype check
3113 Node* not_subtype_ctrl = gen_subtype_check( obj_klass, superklass );
3114
3115 // Plug in success path into the merge
3116 cast_obj = _gvn.transform(new CheckCastPPNode(control(), not_null_obj, toop));
3117 // Failure path ends in uncommon trap (or may be dead - failure impossible)
3118 if (failure_control == NULL) {
3119 if (not_subtype_ctrl != top()) { // If failure is possible
3120 PreserveJVMState pjvms(this);
3121 set_control(not_subtype_ctrl);
3122 builtin_throw(Deoptimization::Reason_class_check, obj_klass);
3123 }
3124 } else {
3125 (*failure_control) = not_subtype_ctrl;
3126 }
3127 }
3128
3129 region->init_req(_obj_path, control());
3130 phi ->init_req(_obj_path, cast_obj);
3131
3132 // A merge of NULL or Casted-NotNull obj
3133 Node* res = _gvn.transform(phi);
3134
3135 // Note I do NOT always 'replace_in_map(obj,result)' here.
3136 // if( tk->klass()->can_be_primary_super() )
3137 // This means that if I successfully store an Object into an array-of-String
3138 // I 'forget' that the Object is really now known to be a String. I have to
3139 // do this because we don't have true union types for interfaces - if I store
3140 // a Baz into an array-of-Interface and then tell the optimizer it's an
3141 // Interface, I forget that it's also a Baz and cannot do Baz-like field
3142 // references to it. FIX THIS WHEN UNION TYPES APPEAR!
3143 // replace_in_map( obj, res );
3144
3145 // Return final merged results
3146 set_control( _gvn.transform(region) );
3147 record_for_igvn(region);
3148
3149 return record_profiled_receiver_for_speculation(res);
3150 }
3151
3152 //------------------------------next_monitor-----------------------------------
3153 // What number should be given to the next monitor?
3154 int GraphKit::next_monitor() {
3155 int current = jvms()->monitor_depth()* C->sync_stack_slots();
3156 int next = current + C->sync_stack_slots();
3157 // Keep the toplevel high water mark current:
3158 if (C->fixed_slots() < next) C->set_fixed_slots(next);
3159 return current;
3160 }
3161
3162 //------------------------------insert_mem_bar---------------------------------
3163 // Memory barrier to avoid floating things around
3164 // The membar serves as a pinch point between both control and all memory slices.
3165 Node* GraphKit::insert_mem_bar(int opcode, Node* precedent) {
3166 MemBarNode* mb = MemBarNode::make(C, opcode, Compile::AliasIdxBot, precedent);
3167 mb->init_req(TypeFunc::Control, control());
3168 mb->init_req(TypeFunc::Memory, reset_memory());
3169 Node* membar = _gvn.transform(mb);
3170 set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control)));
3171 set_all_memory_call(membar);
3172 return membar;
3173 }
3174
3175 //-------------------------insert_mem_bar_volatile----------------------------
3176 // Memory barrier to avoid floating things around
3177 // The membar serves as a pinch point between both control and memory(alias_idx).
3178 // If you want to make a pinch point on all memory slices, do not use this
3179 // function (even with AliasIdxBot); use insert_mem_bar() instead.
3180 Node* GraphKit::insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent) {
3181 // When Parse::do_put_xxx updates a volatile field, it appends a series
3182 // of MemBarVolatile nodes, one for *each* volatile field alias category.
3183 // The first membar is on the same memory slice as the field store opcode.
3184 // This forces the membar to follow the store. (Bug 6500685 broke this.)
3185 // All the other membars (for other volatile slices, including AliasIdxBot,
3186 // which stands for all unknown volatile slices) are control-dependent
3187 // on the first membar. This prevents later volatile loads or stores
3188 // from sliding up past the just-emitted store.
3189
3190 MemBarNode* mb = MemBarNode::make(C, opcode, alias_idx, precedent);
3191 mb->set_req(TypeFunc::Control,control());
3192 if (alias_idx == Compile::AliasIdxBot) {
3193 mb->set_req(TypeFunc::Memory, merged_memory()->base_memory());
3194 } else {
3195 assert(!(opcode == Op_Initialize && alias_idx != Compile::AliasIdxRaw), "fix caller");
3196 mb->set_req(TypeFunc::Memory, memory(alias_idx));
3197 }
3198 Node* membar = _gvn.transform(mb);
3199 set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control)));
3200 if (alias_idx == Compile::AliasIdxBot) {
3201 merged_memory()->set_base_memory(_gvn.transform(new ProjNode(membar, TypeFunc::Memory)));
3202 } else {
3203 set_memory(_gvn.transform(new ProjNode(membar, TypeFunc::Memory)),alias_idx);
3204 }
3205 return membar;
3206 }
3207
3208 //------------------------------shared_lock------------------------------------
3209 // Emit locking code.
3210 FastLockNode* GraphKit::shared_lock(Node* obj) {
3211 // bci is either a monitorenter bc or InvocationEntryBci
3212 // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3213 assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3214
3215 if( !GenerateSynchronizationCode )
3216 return NULL; // Not locking things?
3217 if (stopped()) // Dead monitor?
3218 return NULL;
3219
3220 assert(dead_locals_are_killed(), "should kill locals before sync. point");
3221
3222 // Box the stack location
3223 Node* box = _gvn.transform(new BoxLockNode(next_monitor()));
3224 Node* mem = reset_memory();
3225
3226 FastLockNode * flock = _gvn.transform(new FastLockNode(0, obj, box) )->as_FastLock();
3227 if (UseBiasedLocking && PrintPreciseBiasedLockingStatistics) {
3228 // Create the counters for this fast lock.
3229 flock->create_lock_counter(sync_jvms()); // sync_jvms used to get current bci
3230 }
3231
3232 // Create the rtm counters for this fast lock if needed.
3233 flock->create_rtm_lock_counter(sync_jvms()); // sync_jvms used to get current bci
3234
3235 // Add monitor to debug info for the slow path. If we block inside the
3236 // slow path and de-opt, we need the monitor hanging around
3237 map()->push_monitor( flock );
3238
3239 const TypeFunc *tf = LockNode::lock_type();
3240 LockNode *lock = new LockNode(C, tf);
3241
3242 lock->init_req( TypeFunc::Control, control() );
3243 lock->init_req( TypeFunc::Memory , mem );
3244 lock->init_req( TypeFunc::I_O , top() ) ; // does no i/o
3245 lock->init_req( TypeFunc::FramePtr, frameptr() );
3246 lock->init_req( TypeFunc::ReturnAdr, top() );
3247
3248 lock->init_req(TypeFunc::Parms + 0, obj);
3249 lock->init_req(TypeFunc::Parms + 1, box);
3250 lock->init_req(TypeFunc::Parms + 2, flock);
3251 add_safepoint_edges(lock);
3252
3253 lock = _gvn.transform( lock )->as_Lock();
3254
3255 // lock has no side-effects, sets few values
3256 set_predefined_output_for_runtime_call(lock, mem, TypeRawPtr::BOTTOM);
3257
3258 insert_mem_bar(Op_MemBarAcquireLock);
3259
3260 // Add this to the worklist so that the lock can be eliminated
3261 record_for_igvn(lock);
3262
3263 #ifndef PRODUCT
3264 if (PrintLockStatistics) {
3265 // Update the counter for this lock. Don't bother using an atomic
3266 // operation since we don't require absolute accuracy.
3267 lock->create_lock_counter(map()->jvms());
3268 increment_counter(lock->counter()->addr());
3269 }
3270 #endif
3271
3272 return flock;
3273 }
3274
3275
3276 //------------------------------shared_unlock----------------------------------
3277 // Emit unlocking code.
3278 void GraphKit::shared_unlock(Node* box, Node* obj) {
3279 // bci is either a monitorenter bc or InvocationEntryBci
3280 // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3281 assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3282
3283 if( !GenerateSynchronizationCode )
3284 return;
3285 if (stopped()) { // Dead monitor?
3286 map()->pop_monitor(); // Kill monitor from debug info
3287 return;
3288 }
3289
3290 // Memory barrier to avoid floating things down past the locked region
3291 insert_mem_bar(Op_MemBarReleaseLock);
3292
3293 const TypeFunc *tf = OptoRuntime::complete_monitor_exit_Type();
3294 UnlockNode *unlock = new UnlockNode(C, tf);
3295 #ifdef ASSERT
3296 unlock->set_dbg_jvms(sync_jvms());
3297 #endif
3298 uint raw_idx = Compile::AliasIdxRaw;
3299 unlock->init_req( TypeFunc::Control, control() );
3300 unlock->init_req( TypeFunc::Memory , memory(raw_idx) );
3301 unlock->init_req( TypeFunc::I_O , top() ) ; // does no i/o
3302 unlock->init_req( TypeFunc::FramePtr, frameptr() );
3303 unlock->init_req( TypeFunc::ReturnAdr, top() );
3304
3305 unlock->init_req(TypeFunc::Parms + 0, obj);
3306 unlock->init_req(TypeFunc::Parms + 1, box);
3307 unlock = _gvn.transform(unlock)->as_Unlock();
3308
3309 Node* mem = reset_memory();
3310
3311 // unlock has no side-effects, sets few values
3312 set_predefined_output_for_runtime_call(unlock, mem, TypeRawPtr::BOTTOM);
3313
3314 // Kill monitor from debug info
3315 map()->pop_monitor( );
3316 }
3317
3318 //-------------------------------get_layout_helper-----------------------------
3319 // If the given klass is a constant or known to be an array,
3320 // fetch the constant layout helper value into constant_value
3321 // and return (Node*)NULL. Otherwise, load the non-constant
3322 // layout helper value, and return the node which represents it.
3323 // This two-faced routine is useful because allocation sites
3324 // almost always feature constant types.
3325 Node* GraphKit::get_layout_helper(Node* klass_node, jint& constant_value) {
3326 const TypeKlassPtr* inst_klass = _gvn.type(klass_node)->isa_klassptr();
3327 if (!StressReflectiveCode && inst_klass != NULL) {
3328 ciKlass* klass = inst_klass->klass();
3329 bool xklass = inst_klass->klass_is_exact();
3330 if (xklass || klass->is_array_klass()) {
3331 jint lhelper = klass->layout_helper();
3332 if (lhelper != Klass::_lh_neutral_value) {
3333 constant_value = lhelper;
3334 return (Node*) NULL;
3335 }
3336 }
3337 }
3338 constant_value = Klass::_lh_neutral_value; // put in a known value
3339 Node* lhp = basic_plus_adr(klass_node, klass_node, in_bytes(Klass::layout_helper_offset()));
3340 return make_load(NULL, lhp, TypeInt::INT, T_INT, MemNode::unordered);
3341 }
3342
3343 // We just put in an allocate/initialize with a big raw-memory effect.
3344 // Hook selected additional alias categories on the initialization.
3345 static void hook_memory_on_init(GraphKit& kit, int alias_idx,
3346 MergeMemNode* init_in_merge,
3347 Node* init_out_raw) {
3348 DEBUG_ONLY(Node* init_in_raw = init_in_merge->base_memory());
3349 assert(init_in_merge->memory_at(alias_idx) == init_in_raw, "");
3350
3351 Node* prevmem = kit.memory(alias_idx);
3352 init_in_merge->set_memory_at(alias_idx, prevmem);
3353 kit.set_memory(init_out_raw, alias_idx);
3354 }
3355
3356 //---------------------------set_output_for_allocation-------------------------
3357 Node* GraphKit::set_output_for_allocation(AllocateNode* alloc,
3358 const TypeOopPtr* oop_type,
3359 bool deoptimize_on_exception) {
3360 int rawidx = Compile::AliasIdxRaw;
3361 alloc->set_req( TypeFunc::FramePtr, frameptr() );
3362 add_safepoint_edges(alloc);
3363 Node* allocx = _gvn.transform(alloc);
3364 set_control( _gvn.transform(new ProjNode(allocx, TypeFunc::Control) ) );
3365 // create memory projection for i_o
3366 set_memory ( _gvn.transform( new ProjNode(allocx, TypeFunc::Memory, true) ), rawidx );
3367 make_slow_call_ex(allocx, env()->Throwable_klass(), true, deoptimize_on_exception);
3368
3369 // create a memory projection as for the normal control path
3370 Node* malloc = _gvn.transform(new ProjNode(allocx, TypeFunc::Memory));
3371 set_memory(malloc, rawidx);
3372
3373 // a normal slow-call doesn't change i_o, but an allocation does
3374 // we create a separate i_o projection for the normal control path
3375 set_i_o(_gvn.transform( new ProjNode(allocx, TypeFunc::I_O, false) ) );
3376 Node* rawoop = _gvn.transform( new ProjNode(allocx, TypeFunc::Parms) );
3377
3378 // put in an initialization barrier
3379 InitializeNode* init = insert_mem_bar_volatile(Op_Initialize, rawidx,
3380 rawoop)->as_Initialize();
3381 assert(alloc->initialization() == init, "2-way macro link must work");
3382 assert(init ->allocation() == alloc, "2-way macro link must work");
3383 {
3384 // Extract memory strands which may participate in the new object's
3385 // initialization, and source them from the new InitializeNode.
3386 // This will allow us to observe initializations when they occur,
3387 // and link them properly (as a group) to the InitializeNode.
3388 assert(init->in(InitializeNode::Memory) == malloc, "");
3389 MergeMemNode* minit_in = MergeMemNode::make(malloc);
3390 init->set_req(InitializeNode::Memory, minit_in);
3391 record_for_igvn(minit_in); // fold it up later, if possible
3392 Node* minit_out = memory(rawidx);
3393 assert(minit_out->is_Proj() && minit_out->in(0) == init, "");
3394 if (oop_type->isa_aryptr()) {
3395 const TypePtr* telemref = oop_type->add_offset(Type::OffsetBot);
3396 int elemidx = C->get_alias_index(telemref);
3397 hook_memory_on_init(*this, elemidx, minit_in, minit_out);
3398 } else if (oop_type->isa_instptr()) {
3399 ciInstanceKlass* ik = oop_type->klass()->as_instance_klass();
3400 for (int i = 0, len = ik->nof_nonstatic_fields(); i < len; i++) {
3401 ciField* field = ik->nonstatic_field_at(i);
3402 if (field->offset() >= TrackedInitializationLimit * HeapWordSize)
3403 continue; // do not bother to track really large numbers of fields
3404 // Find (or create) the alias category for this field:
3405 int fieldidx = C->alias_type(field)->index();
3406 hook_memory_on_init(*this, fieldidx, minit_in, minit_out);
3407 }
3408 }
3409 }
3410
3411 // Cast raw oop to the real thing...
3412 Node* javaoop = new CheckCastPPNode(control(), rawoop, oop_type);
3413 javaoop = _gvn.transform(javaoop);
3414 C->set_recent_alloc(control(), javaoop);
3415 assert(just_allocated_object(control()) == javaoop, "just allocated");
3416
3417 #ifdef ASSERT
3418 { // Verify that the AllocateNode::Ideal_allocation recognizers work:
3419 assert(AllocateNode::Ideal_allocation(rawoop, &_gvn) == alloc,
3420 "Ideal_allocation works");
3421 assert(AllocateNode::Ideal_allocation(javaoop, &_gvn) == alloc,
3422 "Ideal_allocation works");
3423 if (alloc->is_AllocateArray()) {
3424 assert(AllocateArrayNode::Ideal_array_allocation(rawoop, &_gvn) == alloc->as_AllocateArray(),
3425 "Ideal_allocation works");
3426 assert(AllocateArrayNode::Ideal_array_allocation(javaoop, &_gvn) == alloc->as_AllocateArray(),
3427 "Ideal_allocation works");
3428 } else {
3429 assert(alloc->in(AllocateNode::ALength)->is_top(), "no length, please");
3430 }
3431 }
3432 #endif //ASSERT
3433
3434 return javaoop;
3435 }
3436
3437 //---------------------------new_instance--------------------------------------
3438 // This routine takes a klass_node which may be constant (for a static type)
3439 // or may be non-constant (for reflective code). It will work equally well
3440 // for either, and the graph will fold nicely if the optimizer later reduces
3441 // the type to a constant.
3442 // The optional arguments are for specialized use by intrinsics:
3443 // - If 'extra_slow_test' if not null is an extra condition for the slow-path.
3444 // - If 'return_size_val', report the the total object size to the caller.
3445 // - deoptimize_on_exception controls how Java exceptions are handled (rethrow vs deoptimize)
3446 Node* GraphKit::new_instance(Node* klass_node,
3447 Node* extra_slow_test,
3448 Node* *return_size_val,
3449 bool deoptimize_on_exception) {
3450 // Compute size in doublewords
3451 // The size is always an integral number of doublewords, represented
3452 // as a positive bytewise size stored in the klass's layout_helper.
3453 // The layout_helper also encodes (in a low bit) the need for a slow path.
3454 jint layout_con = Klass::_lh_neutral_value;
3455 Node* layout_val = get_layout_helper(klass_node, layout_con);
3456 int layout_is_con = (layout_val == NULL);
3457
3458 if (extra_slow_test == NULL) extra_slow_test = intcon(0);
3459 // Generate the initial go-slow test. It's either ALWAYS (return a
3460 // Node for 1) or NEVER (return a NULL) or perhaps (in the reflective
3461 // case) a computed value derived from the layout_helper.
3462 Node* initial_slow_test = NULL;
3463 if (layout_is_con) {
3464 assert(!StressReflectiveCode, "stress mode does not use these paths");
3465 bool must_go_slow = Klass::layout_helper_needs_slow_path(layout_con);
3466 initial_slow_test = must_go_slow ? intcon(1) : extra_slow_test;
3467 } else { // reflective case
3468 // This reflective path is used by Unsafe.allocateInstance.
3469 // (It may be stress-tested by specifying StressReflectiveCode.)
3470 // Basically, we want to get into the VM is there's an illegal argument.
3471 Node* bit = intcon(Klass::_lh_instance_slow_path_bit);
3472 initial_slow_test = _gvn.transform( new AndINode(layout_val, bit) );
3473 if (extra_slow_test != intcon(0)) {
3474 initial_slow_test = _gvn.transform( new OrINode(initial_slow_test, extra_slow_test) );
3475 }
3476 // (Macro-expander will further convert this to a Bool, if necessary.)
3477 }
3478
3479 // Find the size in bytes. This is easy; it's the layout_helper.
3480 // The size value must be valid even if the slow path is taken.
3481 Node* size = NULL;
3482 if (layout_is_con) {
3483 size = MakeConX(Klass::layout_helper_size_in_bytes(layout_con));
3484 } else { // reflective case
3485 // This reflective path is used by clone and Unsafe.allocateInstance.
3486 size = ConvI2X(layout_val);
3487
3488 // Clear the low bits to extract layout_helper_size_in_bytes:
3489 assert((int)Klass::_lh_instance_slow_path_bit < BytesPerLong, "clear bit");
3490 Node* mask = MakeConX(~ (intptr_t)right_n_bits(LogBytesPerLong));
3491 size = _gvn.transform( new AndXNode(size, mask) );
3492 }
3493 if (return_size_val != NULL) {
3494 (*return_size_val) = size;
3495 }
3496
3497 // This is a precise notnull oop of the klass.
3498 // (Actually, it need not be precise if this is a reflective allocation.)
3499 // It's what we cast the result to.
3500 const TypeKlassPtr* tklass = _gvn.type(klass_node)->isa_klassptr();
3501 if (!tklass) tklass = TypeKlassPtr::OBJECT;
3502 const TypeOopPtr* oop_type = tklass->as_instance_type();
3503
3504 // Now generate allocation code
3505
3506 // The entire memory state is needed for slow path of the allocation
3507 // since GC and deoptimization can happened.
3508 Node *mem = reset_memory();
3509 set_all_memory(mem); // Create new memory state
3510
3511 AllocateNode* alloc = new AllocateNode(C, AllocateNode::alloc_type(Type::TOP),
3512 control(), mem, i_o(),
3513 size, klass_node,
3514 initial_slow_test);
3515
3516 return set_output_for_allocation(alloc, oop_type, deoptimize_on_exception);
3517 }
3518
3519 //-------------------------------new_array-------------------------------------
3520 // helper for both newarray and anewarray
3521 // The 'length' parameter is (obviously) the length of the array.
3522 // See comments on new_instance for the meaning of the other arguments.
3523 Node* GraphKit::new_array(Node* klass_node, // array klass (maybe variable)
3524 Node* length, // number of array elements
3525 int nargs, // number of arguments to push back for uncommon trap
3526 Node* *return_size_val,
3527 bool deoptimize_on_exception) {
3528 jint layout_con = Klass::_lh_neutral_value;
3529 Node* layout_val = get_layout_helper(klass_node, layout_con);
3530 int layout_is_con = (layout_val == NULL);
3531
3532 if (!layout_is_con && !StressReflectiveCode &&
3533 !too_many_traps(Deoptimization::Reason_class_check)) {
3534 // This is a reflective array creation site.
3535 // Optimistically assume that it is a subtype of Object[],
3536 // so that we can fold up all the address arithmetic.
3537 layout_con = Klass::array_layout_helper(T_OBJECT);
3538 Node* cmp_lh = _gvn.transform( new CmpINode(layout_val, intcon(layout_con)) );
3539 Node* bol_lh = _gvn.transform( new BoolNode(cmp_lh, BoolTest::eq) );
3540 { BuildCutout unless(this, bol_lh, PROB_MAX);
3541 inc_sp(nargs);
3542 uncommon_trap(Deoptimization::Reason_class_check,
3543 Deoptimization::Action_maybe_recompile);
3544 }
3545 layout_val = NULL;
3546 layout_is_con = true;
3547 }
3548
3549 // Generate the initial go-slow test. Make sure we do not overflow
3550 // if length is huge (near 2Gig) or negative! We do not need
3551 // exact double-words here, just a close approximation of needed
3552 // double-words. We can't add any offset or rounding bits, lest we
3553 // take a size -1 of bytes and make it positive. Use an unsigned
3554 // compare, so negative sizes look hugely positive.
3555 int fast_size_limit = FastAllocateSizeLimit;
3556 if (layout_is_con) {
3557 assert(!StressReflectiveCode, "stress mode does not use these paths");
3558 // Increase the size limit if we have exact knowledge of array type.
3559 int log2_esize = Klass::layout_helper_log2_element_size(layout_con);
3560 fast_size_limit <<= (LogBytesPerLong - log2_esize);
3561 }
3562
3563 Node* initial_slow_cmp = _gvn.transform( new CmpUNode( length, intcon( fast_size_limit ) ) );
3564 Node* initial_slow_test = _gvn.transform( new BoolNode( initial_slow_cmp, BoolTest::gt ) );
3565
3566 // --- Size Computation ---
3567 // array_size = round_to_heap(array_header + (length << elem_shift));
3568 // where round_to_heap(x) == align_to(x, MinObjAlignmentInBytes)
3569 // and align_to(x, y) == ((x + y-1) & ~(y-1))
3570 // The rounding mask is strength-reduced, if possible.
3571 int round_mask = MinObjAlignmentInBytes - 1;
3572 Node* header_size = NULL;
3573 int header_size_min = arrayOopDesc::base_offset_in_bytes(T_BYTE);
3574 // (T_BYTE has the weakest alignment and size restrictions...)
3575 if (layout_is_con) {
3576 int hsize = Klass::layout_helper_header_size(layout_con);
3577 int eshift = Klass::layout_helper_log2_element_size(layout_con);
3578 BasicType etype = Klass::layout_helper_element_type(layout_con);
3579 if ((round_mask & ~right_n_bits(eshift)) == 0)
3580 round_mask = 0; // strength-reduce it if it goes away completely
3581 assert((hsize & right_n_bits(eshift)) == 0, "hsize is pre-rounded");
3582 assert(header_size_min <= hsize, "generic minimum is smallest");
3583 header_size_min = hsize;
3584 header_size = intcon(hsize + round_mask);
3585 } else {
3586 Node* hss = intcon(Klass::_lh_header_size_shift);
3587 Node* hsm = intcon(Klass::_lh_header_size_mask);
3588 Node* hsize = _gvn.transform( new URShiftINode(layout_val, hss) );
3589 hsize = _gvn.transform( new AndINode(hsize, hsm) );
3590 Node* mask = intcon(round_mask);
3591 header_size = _gvn.transform( new AddINode(hsize, mask) );
3592 }
3593
3594 Node* elem_shift = NULL;
3595 if (layout_is_con) {
3596 int eshift = Klass::layout_helper_log2_element_size(layout_con);
3597 if (eshift != 0)
3598 elem_shift = intcon(eshift);
3599 } else {
3600 // There is no need to mask or shift this value.
3601 // The semantics of LShiftINode include an implicit mask to 0x1F.
3602 assert(Klass::_lh_log2_element_size_shift == 0, "use shift in place");
3603 elem_shift = layout_val;
3604 }
3605
3606 // Transition to native address size for all offset calculations:
3607 Node* lengthx = ConvI2X(length);
3608 Node* headerx = ConvI2X(header_size);
3609 #ifdef _LP64
3610 { const TypeInt* tilen = _gvn.find_int_type(length);
3611 if (tilen != NULL && tilen->_lo < 0) {
3612 // Add a manual constraint to a positive range. Cf. array_element_address.
3613 jint size_max = fast_size_limit;
3614 if (size_max > tilen->_hi) size_max = tilen->_hi;
3615 const TypeInt* tlcon = TypeInt::make(0, size_max, Type::WidenMin);
3616
3617 // Only do a narrow I2L conversion if the range check passed.
3618 IfNode* iff = new IfNode(control(), initial_slow_test, PROB_MIN, COUNT_UNKNOWN);
3619 _gvn.transform(iff);
3620 RegionNode* region = new RegionNode(3);
3621 _gvn.set_type(region, Type::CONTROL);
3622 lengthx = new PhiNode(region, TypeLong::LONG);
3623 _gvn.set_type(lengthx, TypeLong::LONG);
3624
3625 // Range check passed. Use ConvI2L node with narrow type.
3626 Node* passed = IfFalse(iff);
3627 region->init_req(1, passed);
3628 // Make I2L conversion control dependent to prevent it from
3629 // floating above the range check during loop optimizations.
3630 lengthx->init_req(1, C->constrained_convI2L(&_gvn, length, tlcon, passed));
3631
3632 // Range check failed. Use ConvI2L with wide type because length may be invalid.
3633 region->init_req(2, IfTrue(iff));
3634 lengthx->init_req(2, ConvI2X(length));
3635
3636 set_control(region);
3637 record_for_igvn(region);
3638 record_for_igvn(lengthx);
3639 }
3640 }
3641 #endif
3642
3643 // Combine header size (plus rounding) and body size. Then round down.
3644 // This computation cannot overflow, because it is used only in two
3645 // places, one where the length is sharply limited, and the other
3646 // after a successful allocation.
3647 Node* abody = lengthx;
3648 if (elem_shift != NULL)
3649 abody = _gvn.transform( new LShiftXNode(lengthx, elem_shift) );
3650 Node* size = _gvn.transform( new AddXNode(headerx, abody) );
3651 if (round_mask != 0) {
3652 Node* mask = MakeConX(~round_mask);
3653 size = _gvn.transform( new AndXNode(size, mask) );
3654 }
3655 // else if round_mask == 0, the size computation is self-rounding
3656
3657 if (return_size_val != NULL) {
3658 // This is the size
3659 (*return_size_val) = size;
3660 }
3661
3662 // Now generate allocation code
3663
3664 // The entire memory state is needed for slow path of the allocation
3665 // since GC and deoptimization can happened.
3666 Node *mem = reset_memory();
3667 set_all_memory(mem); // Create new memory state
3668
3669 if (initial_slow_test->is_Bool()) {
3670 // Hide it behind a CMoveI, or else PhaseIdealLoop::split_up will get sick.
3671 initial_slow_test = initial_slow_test->as_Bool()->as_int_value(&_gvn);
3672 }
3673
3674 // Create the AllocateArrayNode and its result projections
3675 AllocateArrayNode* alloc
3676 = new AllocateArrayNode(C, AllocateArrayNode::alloc_type(TypeInt::INT),
3677 control(), mem, i_o(),
3678 size, klass_node,
3679 initial_slow_test,
3680 length);
3681
3682 // Cast to correct type. Note that the klass_node may be constant or not,
3683 // and in the latter case the actual array type will be inexact also.
3684 // (This happens via a non-constant argument to inline_native_newArray.)
3685 // In any case, the value of klass_node provides the desired array type.
3686 const TypeInt* length_type = _gvn.find_int_type(length);
3687 const TypeOopPtr* ary_type = _gvn.type(klass_node)->is_klassptr()->as_instance_type();
3688 if (ary_type->isa_aryptr() && length_type != NULL) {
3689 // Try to get a better type than POS for the size
3690 ary_type = ary_type->is_aryptr()->cast_to_size(length_type);
3691 }
3692
3693 Node* javaoop = set_output_for_allocation(alloc, ary_type, deoptimize_on_exception);
3694
3695 // Cast length on remaining path to be as narrow as possible
3696 if (map()->find_edge(length) >= 0) {
3697 Node* ccast = alloc->make_ideal_length(ary_type, &_gvn);
3698 if (ccast != length) {
3699 _gvn.set_type_bottom(ccast);
3700 record_for_igvn(ccast);
3701 replace_in_map(length, ccast);
3702 }
3703 }
3704
3705 return javaoop;
3706 }
3707
3708 // The following "Ideal_foo" functions are placed here because they recognize
3709 // the graph shapes created by the functions immediately above.
3710
3711 //---------------------------Ideal_allocation----------------------------------
3712 // Given an oop pointer or raw pointer, see if it feeds from an AllocateNode.
3713 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase) {
3714 if (ptr == NULL) { // reduce dumb test in callers
3715 return NULL;
3716 }
3717 if (ptr->is_CheckCastPP()) { // strip only one raw-to-oop cast
3718 ptr = ptr->in(1);
3719 if (ptr == NULL) return NULL;
3720 }
3721 // Return NULL for allocations with several casts:
3722 // j.l.reflect.Array.newInstance(jobject, jint)
3723 // Object.clone()
3724 // to keep more precise type from last cast.
3725 if (ptr->is_Proj()) {
3726 Node* allo = ptr->in(0);
3727 if (allo != NULL && allo->is_Allocate()) {
3728 return allo->as_Allocate();
3729 }
3730 }
3731 // Report failure to match.
3732 return NULL;
3733 }
3734
3735 // Fancy version which also strips off an offset (and reports it to caller).
3736 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase,
3737 intptr_t& offset) {
3738 Node* base = AddPNode::Ideal_base_and_offset(ptr, phase, offset);
3739 if (base == NULL) return NULL;
3740 return Ideal_allocation(base, phase);
3741 }
3742
3743 // Trace Initialize <- Proj[Parm] <- Allocate
3744 AllocateNode* InitializeNode::allocation() {
3745 Node* rawoop = in(InitializeNode::RawAddress);
3746 if (rawoop->is_Proj()) {
3747 Node* alloc = rawoop->in(0);
3748 if (alloc->is_Allocate()) {
3749 return alloc->as_Allocate();
3750 }
3751 }
3752 return NULL;
3753 }
3754
3755 // Trace Allocate -> Proj[Parm] -> Initialize
3756 InitializeNode* AllocateNode::initialization() {
3757 ProjNode* rawoop = proj_out_or_null(AllocateNode::RawAddress);
3758 if (rawoop == NULL) return NULL;
3759 for (DUIterator_Fast imax, i = rawoop->fast_outs(imax); i < imax; i++) {
3760 Node* init = rawoop->fast_out(i);
3761 if (init->is_Initialize()) {
3762 assert(init->as_Initialize()->allocation() == this, "2-way link");
3763 return init->as_Initialize();
3764 }
3765 }
3766 return NULL;
3767 }
3768
3769 //----------------------------- loop predicates ---------------------------
3770
3771 //------------------------------add_predicate_impl----------------------------
3772 void GraphKit::add_predicate_impl(Deoptimization::DeoptReason reason, int nargs) {
3773 // Too many traps seen?
3774 if (too_many_traps(reason)) {
3775 #ifdef ASSERT
3776 if (TraceLoopPredicate) {
3777 int tc = C->trap_count(reason);
3778 tty->print("too many traps=%s tcount=%d in ",
3779 Deoptimization::trap_reason_name(reason), tc);
3780 method()->print(); // which method has too many predicate traps
3781 tty->cr();
3782 }
3783 #endif
3784 // We cannot afford to take more traps here,
3785 // do not generate predicate.
3786 return;
3787 }
3788
3789 Node *cont = _gvn.intcon(1);
3790 Node* opq = _gvn.transform(new Opaque1Node(C, cont));
3791 Node *bol = _gvn.transform(new Conv2BNode(opq));
3792 IfNode* iff = create_and_map_if(control(), bol, PROB_MAX, COUNT_UNKNOWN);
3793 Node* iffalse = _gvn.transform(new IfFalseNode(iff));
3794 C->add_predicate_opaq(opq);
3795 {
3796 PreserveJVMState pjvms(this);
3797 set_control(iffalse);
3798 inc_sp(nargs);
3799 uncommon_trap(reason, Deoptimization::Action_maybe_recompile);
3800 }
3801 Node* iftrue = _gvn.transform(new IfTrueNode(iff));
3802 set_control(iftrue);
3803 }
3804
3805 //------------------------------add_predicate---------------------------------
3806 void GraphKit::add_predicate(int nargs) {
3807 if (UseLoopPredicate) {
3808 add_predicate_impl(Deoptimization::Reason_predicate, nargs);
3809 }
3810 // loop's limit check predicate should be near the loop.
3811 add_predicate_impl(Deoptimization::Reason_loop_limit_check, nargs);
3812 }
3813
3814 //----------------------------- store barriers ----------------------------
3815 #define __ ideal.
3816
3817 void GraphKit::sync_kit(IdealKit& ideal) {
3818 set_all_memory(__ merged_memory());
3819 set_i_o(__ i_o());
3820 set_control(__ ctrl());
3821 }
3822
3823 void GraphKit::final_sync(IdealKit& ideal) {
3824 // Final sync IdealKit and graphKit.
3825 sync_kit(ideal);
3826 }
3827
3828 Node* GraphKit::byte_map_base_node() {
3829 // Get base of card map
3830 CardTableModRefBS* ct =
3831 barrier_set_cast<CardTableModRefBS>(Universe::heap()->barrier_set());
3832 assert(sizeof(*ct->byte_map_base) == sizeof(jbyte), "adjust users of this code");
3833 if (ct->byte_map_base != NULL) {
3834 return makecon(TypeRawPtr::make((address)ct->byte_map_base));
3835 } else {
3836 return null();
3837 }
3838 }
3839
3840 // vanilla/CMS post barrier
3841 // Insert a write-barrier store. This is to let generational GC work; we have
3842 // to flag all oop-stores before the next GC point.
3843 void GraphKit::write_barrier_post(Node* oop_store,
3844 Node* obj,
3845 Node* adr,
3846 uint adr_idx,
3847 Node* val,
3848 bool use_precise) {
3849 // No store check needed if we're storing a NULL or an old object
3850 // (latter case is probably a string constant). The concurrent
3851 // mark sweep garbage collector, however, needs to have all nonNull
3852 // oop updates flagged via card-marks.
3853 if (val != NULL && val->is_Con()) {
3854 // must be either an oop or NULL
3855 const Type* t = val->bottom_type();
3856 if (t == TypePtr::NULL_PTR || t == Type::TOP)
3857 // stores of null never (?) need barriers
3858 return;
3859 }
3860
3861 if (use_ReduceInitialCardMarks()
3862 && obj == just_allocated_object(control())) {
3863 // We can skip marks on a freshly-allocated object in Eden.
3864 // Keep this code in sync with new_store_pre_barrier() in runtime.cpp.
3865 // That routine informs GC to take appropriate compensating steps,
3866 // upon a slow-path allocation, so as to make this card-mark
3867 // elision safe.
3868 return;
3869 }
3870
3871 if (!use_precise) {
3872 // All card marks for a (non-array) instance are in one place:
3873 adr = obj;
3874 }
3875 // (Else it's an array (or unknown), and we want more precise card marks.)
3876 assert(adr != NULL, "");
3877
3878 IdealKit ideal(this, true);
3879
3880 // Convert the pointer to an int prior to doing math on it
3881 Node* cast = __ CastPX(__ ctrl(), adr);
3882
3883 // Divide by card size
3884 assert(Universe::heap()->barrier_set()->is_a(BarrierSet::CardTableModRef),
3885 "Only one we handle so far.");
3886 Node* card_offset = __ URShiftX( cast, __ ConI(CardTableModRefBS::card_shift) );
3887
3888 // Combine card table base and card offset
3889 Node* card_adr = __ AddP(__ top(), byte_map_base_node(), card_offset );
3890
3891 // Get the alias_index for raw card-mark memory
3892 int adr_type = Compile::AliasIdxRaw;
3893 Node* zero = __ ConI(0); // Dirty card value
3894 BasicType bt = T_BYTE;
3895
3896 if (UseConcMarkSweepGC && UseCondCardMark) {
3897 insert_mem_bar(Op_MemBarVolatile); // StoreLoad barrier
3898 __ sync_kit(this);
3899 }
3900
3901 if (UseCondCardMark) {
3902 // The classic GC reference write barrier is typically implemented
3903 // as a store into the global card mark table. Unfortunately
3904 // unconditional stores can result in false sharing and excessive
3905 // coherence traffic as well as false transactional aborts.
3906 // UseCondCardMark enables MP "polite" conditional card mark
3907 // stores. In theory we could relax the load from ctrl() to
3908 // no_ctrl, but that doesn't buy much latitude.
3909 Node* card_val = __ load( __ ctrl(), card_adr, TypeInt::BYTE, bt, adr_type);
3910 __ if_then(card_val, BoolTest::ne, zero);
3911 }
3912
3913 // Smash zero into card
3914 if( !UseConcMarkSweepGC ) {
3915 __ store(__ ctrl(), card_adr, zero, bt, adr_type, MemNode::unordered);
3916 } else {
3917 // Specialized path for CM store barrier
3918 __ storeCM(__ ctrl(), card_adr, zero, oop_store, adr_idx, bt, adr_type);
3919 }
3920
3921 if (UseCondCardMark) {
3922 __ end_if();
3923 }
3924
3925 // Final sync IdealKit and GraphKit.
3926 final_sync(ideal);
3927 }
3928 /*
3929 * Determine if the G1 pre-barrier can be removed. The pre-barrier is
3930 * required by SATB to make sure all objects live at the start of the
3931 * marking are kept alive, all reference updates need to any previous
3932 * reference stored before writing.
3933 *
3934 * If the previous value is NULL there is no need to save the old value.
3935 * References that are NULL are filtered during runtime by the barrier
3936 * code to avoid unnecessary queuing.
3937 *
3938 * However in the case of newly allocated objects it might be possible to
3939 * prove that the reference about to be overwritten is NULL during compile
3940 * time and avoid adding the barrier code completely.
3941 *
3942 * The compiler needs to determine that the object in which a field is about
3943 * to be written is newly allocated, and that no prior store to the same field
3944 * has happened since the allocation.
3945 *
3946 * Returns true if the pre-barrier can be removed
3947 */
3948 bool GraphKit::g1_can_remove_pre_barrier(PhaseTransform* phase, Node* adr,
3949 BasicType bt, uint adr_idx) {
3950 intptr_t offset = 0;
3951 Node* base = AddPNode::Ideal_base_and_offset(adr, phase, offset);
3952 AllocateNode* alloc = AllocateNode::Ideal_allocation(base, phase);
3953
3954 if (offset == Type::OffsetBot) {
3955 return false; // cannot unalias unless there are precise offsets
3956 }
3957
3958 if (alloc == NULL) {
3959 return false; // No allocation found
3960 }
3961
3962 intptr_t size_in_bytes = type2aelembytes(bt);
3963
3964 Node* mem = memory(adr_idx); // start searching here...
3965
3966 for (int cnt = 0; cnt < 50; cnt++) {
3967
3968 if (mem->is_Store()) {
3969
3970 Node* st_adr = mem->in(MemNode::Address);
3971 intptr_t st_offset = 0;
3972 Node* st_base = AddPNode::Ideal_base_and_offset(st_adr, phase, st_offset);
3973
3974 if (st_base == NULL) {
3975 break; // inscrutable pointer
3976 }
3977
3978 // Break we have found a store with same base and offset as ours so break
3979 if (st_base == base && st_offset == offset) {
3980 break;
3981 }
3982
3983 if (st_offset != offset && st_offset != Type::OffsetBot) {
3984 const int MAX_STORE = BytesPerLong;
3985 if (st_offset >= offset + size_in_bytes ||
3986 st_offset <= offset - MAX_STORE ||
3987 st_offset <= offset - mem->as_Store()->memory_size()) {
3988 // Success: The offsets are provably independent.
3989 // (You may ask, why not just test st_offset != offset and be done?
3990 // The answer is that stores of different sizes can co-exist
3991 // in the same sequence of RawMem effects. We sometimes initialize
3992 // a whole 'tile' of array elements with a single jint or jlong.)
3993 mem = mem->in(MemNode::Memory);
3994 continue; // advance through independent store memory
3995 }
3996 }
3997
3998 if (st_base != base
3999 && MemNode::detect_ptr_independence(base, alloc, st_base,
4000 AllocateNode::Ideal_allocation(st_base, phase),
4001 phase)) {
4002 // Success: The bases are provably independent.
4003 mem = mem->in(MemNode::Memory);
4004 continue; // advance through independent store memory
4005 }
4006 } else if (mem->is_Proj() && mem->in(0)->is_Initialize()) {
4007
4008 InitializeNode* st_init = mem->in(0)->as_Initialize();
4009 AllocateNode* st_alloc = st_init->allocation();
4010
4011 // Make sure that we are looking at the same allocation site.
4012 // The alloc variable is guaranteed to not be null here from earlier check.
4013 if (alloc == st_alloc) {
4014 // Check that the initialization is storing NULL so that no previous store
4015 // has been moved up and directly write a reference
4016 Node* captured_store = st_init->find_captured_store(offset,
4017 type2aelembytes(T_OBJECT),
4018 phase);
4019 if (captured_store == NULL || captured_store == st_init->zero_memory()) {
4020 return true;
4021 }
4022 }
4023 }
4024
4025 // Unless there is an explicit 'continue', we must bail out here,
4026 // because 'mem' is an inscrutable memory state (e.g., a call).
4027 break;
4028 }
4029
4030 return false;
4031 }
4032
4033 // G1 pre/post barriers
4034 void GraphKit::g1_write_barrier_pre(bool do_load,
4035 Node* obj,
4036 Node* adr,
4037 uint alias_idx,
4038 Node* val,
4039 const TypeOopPtr* val_type,
4040 Node* pre_val,
4041 BasicType bt) {
4042
4043 // Some sanity checks
4044 // Note: val is unused in this routine.
4045
4046 if (do_load) {
4047 // We need to generate the load of the previous value
4048 assert(obj != NULL, "must have a base");
4049 assert(adr != NULL, "where are loading from?");
4050 assert(pre_val == NULL, "loaded already?");
4051 assert(val_type != NULL, "need a type");
4052
4053 if (use_ReduceInitialCardMarks()
4054 && g1_can_remove_pre_barrier(&_gvn, adr, bt, alias_idx)) {
4055 return;
4056 }
4057
4058 } else {
4059 // In this case both val_type and alias_idx are unused.
4060 assert(pre_val != NULL, "must be loaded already");
4061 // Nothing to be done if pre_val is null.
4062 if (pre_val->bottom_type() == TypePtr::NULL_PTR) return;
4063 assert(pre_val->bottom_type()->basic_type() == T_OBJECT, "or we shouldn't be here");
4064 }
4065 assert(bt == T_OBJECT, "or we shouldn't be here");
4066
4067 IdealKit ideal(this, true);
4068
4069 Node* tls = __ thread(); // ThreadLocalStorage
4070
4071 Node* no_ctrl = NULL;
4072 Node* no_base = __ top();
4073 Node* zero = __ ConI(0);
4074 Node* zeroX = __ ConX(0);
4075
4076 float likely = PROB_LIKELY(0.999);
4077 float unlikely = PROB_UNLIKELY(0.999);
4078
4079 BasicType active_type = in_bytes(SATBMarkQueue::byte_width_of_active()) == 4 ? T_INT : T_BYTE;
4080 assert(in_bytes(SATBMarkQueue::byte_width_of_active()) == 4 || in_bytes(SATBMarkQueue::byte_width_of_active()) == 1, "flag width");
4081
4082 // Offsets into the thread
4083 const int marking_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 648
4084 SATBMarkQueue::byte_offset_of_active());
4085 const int index_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 656
4086 SATBMarkQueue::byte_offset_of_index());
4087 const int buffer_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 652
4088 SATBMarkQueue::byte_offset_of_buf());
4089
4090 // Now the actual pointers into the thread
4091 Node* marking_adr = __ AddP(no_base, tls, __ ConX(marking_offset));
4092 Node* buffer_adr = __ AddP(no_base, tls, __ ConX(buffer_offset));
4093 Node* index_adr = __ AddP(no_base, tls, __ ConX(index_offset));
4094
4095 // Now some of the values
4096 Node* marking = __ load(__ ctrl(), marking_adr, TypeInt::INT, active_type, Compile::AliasIdxRaw);
4097
4098 // if (!marking)
4099 __ if_then(marking, BoolTest::ne, zero, unlikely); {
4100 BasicType index_bt = TypeX_X->basic_type();
4101 assert(sizeof(size_t) == type2aelembytes(index_bt), "Loading G1 SATBMarkQueue::_index with wrong size.");
4102 Node* index = __ load(__ ctrl(), index_adr, TypeX_X, index_bt, Compile::AliasIdxRaw);
4103
4104 if (do_load) {
4105 // load original value
4106 // alias_idx correct??
4107 pre_val = __ load(__ ctrl(), adr, val_type, bt, alias_idx);
4108 }
4109
4110 // if (pre_val != NULL)
4111 __ if_then(pre_val, BoolTest::ne, null()); {
4112 Node* buffer = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw);
4113
4114 // is the queue for this thread full?
4115 __ if_then(index, BoolTest::ne, zeroX, likely); {
4116
4117 // decrement the index
4118 Node* next_index = _gvn.transform(new SubXNode(index, __ ConX(sizeof(intptr_t))));
4119
4120 // Now get the buffer location we will log the previous value into and store it
4121 Node *log_addr = __ AddP(no_base, buffer, next_index);
4122 __ store(__ ctrl(), log_addr, pre_val, T_OBJECT, Compile::AliasIdxRaw, MemNode::unordered);
4123 // update the index
4124 __ store(__ ctrl(), index_adr, next_index, index_bt, Compile::AliasIdxRaw, MemNode::unordered);
4125
4126 } __ else_(); {
4127
4128 // logging buffer is full, call the runtime
4129 const TypeFunc *tf = OptoRuntime::g1_wb_pre_Type();
4130 __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_pre), "g1_wb_pre", pre_val, tls);
4131 } __ end_if(); // (!index)
4132 } __ end_if(); // (pre_val != NULL)
4133 } __ end_if(); // (!marking)
4134
4135 // Final sync IdealKit and GraphKit.
4136 final_sync(ideal);
4137 }
4138
4139 /*
4140 * G1 similar to any GC with a Young Generation requires a way to keep track of
4141 * references from Old Generation to Young Generation to make sure all live
4142 * objects are found. G1 also requires to keep track of object references
4143 * between different regions to enable evacuation of old regions, which is done
4144 * as part of mixed collections. References are tracked in remembered sets and
4145 * is continuously updated as reference are written to with the help of the
4146 * post-barrier.
4147 *
4148 * To reduce the number of updates to the remembered set the post-barrier
4149 * filters updates to fields in objects located in the Young Generation,
4150 * the same region as the reference, when the NULL is being written or
4151 * if the card is already marked as dirty by an earlier write.
4152 *
4153 * Under certain circumstances it is possible to avoid generating the
4154 * post-barrier completely if it is possible during compile time to prove
4155 * the object is newly allocated and that no safepoint exists between the
4156 * allocation and the store.
4157 *
4158 * In the case of slow allocation the allocation code must handle the barrier
4159 * as part of the allocation in the case the allocated object is not located
4160 * in the nursery, this would happen for humongous objects. This is similar to
4161 * how CMS is required to handle this case, see the comments for the method
4162 * CollectedHeap::new_store_pre_barrier and OptoRuntime::new_store_pre_barrier.
4163 * A deferred card mark is required for these objects and handled in the above
4164 * mentioned methods.
4165 *
4166 * Returns true if the post barrier can be removed
4167 */
4168 bool GraphKit::g1_can_remove_post_barrier(PhaseTransform* phase, Node* store,
4169 Node* adr) {
4170 intptr_t offset = 0;
4171 Node* base = AddPNode::Ideal_base_and_offset(adr, phase, offset);
4172 AllocateNode* alloc = AllocateNode::Ideal_allocation(base, phase);
4173
4174 if (offset == Type::OffsetBot) {
4175 return false; // cannot unalias unless there are precise offsets
4176 }
4177
4178 if (alloc == NULL) {
4179 return false; // No allocation found
4180 }
4181
4182 // Start search from Store node
4183 Node* mem = store->in(MemNode::Control);
4184 if (mem->is_Proj() && mem->in(0)->is_Initialize()) {
4185
4186 InitializeNode* st_init = mem->in(0)->as_Initialize();
4187 AllocateNode* st_alloc = st_init->allocation();
4188
4189 // Make sure we are looking at the same allocation
4190 if (alloc == st_alloc) {
4191 return true;
4192 }
4193 }
4194
4195 return false;
4196 }
4197
4198 //
4199 // Update the card table and add card address to the queue
4200 //
4201 void GraphKit::g1_mark_card(IdealKit& ideal,
4202 Node* card_adr,
4203 Node* oop_store,
4204 uint oop_alias_idx,
4205 Node* index,
4206 Node* index_adr,
4207 Node* buffer,
4208 const TypeFunc* tf) {
4209
4210 Node* zero = __ ConI(0);
4211 Node* zeroX = __ ConX(0);
4212 Node* no_base = __ top();
4213 BasicType card_bt = T_BYTE;
4214 // Smash zero into card. MUST BE ORDERED WRT TO STORE
4215 __ storeCM(__ ctrl(), card_adr, zero, oop_store, oop_alias_idx, card_bt, Compile::AliasIdxRaw);
4216
4217 // Now do the queue work
4218 __ if_then(index, BoolTest::ne, zeroX); {
4219
4220 Node* next_index = _gvn.transform(new SubXNode(index, __ ConX(sizeof(intptr_t))));
4221 Node* log_addr = __ AddP(no_base, buffer, next_index);
4222
4223 // Order, see storeCM.
4224 __ store(__ ctrl(), log_addr, card_adr, T_ADDRESS, Compile::AliasIdxRaw, MemNode::unordered);
4225 __ store(__ ctrl(), index_adr, next_index, TypeX_X->basic_type(), Compile::AliasIdxRaw, MemNode::unordered);
4226
4227 } __ else_(); {
4228 __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_post), "g1_wb_post", card_adr, __ thread());
4229 } __ end_if();
4230
4231 }
4232
4233 void GraphKit::g1_write_barrier_post(Node* oop_store,
4234 Node* obj,
4235 Node* adr,
4236 uint alias_idx,
4237 Node* val,
4238 BasicType bt,
4239 bool use_precise) {
4240 // If we are writing a NULL then we need no post barrier
4241
4242 if (val != NULL && val->is_Con() && val->bottom_type() == TypePtr::NULL_PTR) {
4243 // Must be NULL
4244 const Type* t = val->bottom_type();
4245 assert(t == Type::TOP || t == TypePtr::NULL_PTR, "must be NULL");
4246 // No post barrier if writing NULLx
4247 return;
4248 }
4249
4250 if (use_ReduceInitialCardMarks() && obj == just_allocated_object(control())) {
4251 // We can skip marks on a freshly-allocated object in Eden.
4252 // Keep this code in sync with new_store_pre_barrier() in runtime.cpp.
4253 // That routine informs GC to take appropriate compensating steps,
4254 // upon a slow-path allocation, so as to make this card-mark
4255 // elision safe.
4256 return;
4257 }
4258
4259 if (use_ReduceInitialCardMarks()
4260 && g1_can_remove_post_barrier(&_gvn, oop_store, adr)) {
4261 return;
4262 }
4263
4264 if (!use_precise) {
4265 // All card marks for a (non-array) instance are in one place:
4266 adr = obj;
4267 }
4268 // (Else it's an array (or unknown), and we want more precise card marks.)
4269 assert(adr != NULL, "");
4270
4271 IdealKit ideal(this, true);
4272
4273 Node* tls = __ thread(); // ThreadLocalStorage
4274
4275 Node* no_base = __ top();
4276 float likely = PROB_LIKELY(0.999);
4277 float unlikely = PROB_UNLIKELY(0.999);
4278 Node* young_card = __ ConI((jint)G1SATBCardTableModRefBS::g1_young_card_val());
4279 Node* dirty_card = __ ConI((jint)CardTableModRefBS::dirty_card_val());
4280 Node* zeroX = __ ConX(0);
4281
4282 // Get the alias_index for raw card-mark memory
4283 const TypePtr* card_type = TypeRawPtr::BOTTOM;
4284
4285 const TypeFunc *tf = OptoRuntime::g1_wb_post_Type();
4286
4287 // Offsets into the thread
4288 const int index_offset = in_bytes(JavaThread::dirty_card_queue_offset() +
4289 DirtyCardQueue::byte_offset_of_index());
4290 const int buffer_offset = in_bytes(JavaThread::dirty_card_queue_offset() +
4291 DirtyCardQueue::byte_offset_of_buf());
4292
4293 // Pointers into the thread
4294
4295 Node* buffer_adr = __ AddP(no_base, tls, __ ConX(buffer_offset));
4296 Node* index_adr = __ AddP(no_base, tls, __ ConX(index_offset));
4297
4298 // Now some values
4299 // Use ctrl to avoid hoisting these values past a safepoint, which could
4300 // potentially reset these fields in the JavaThread.
4301 Node* index = __ load(__ ctrl(), index_adr, TypeX_X, TypeX_X->basic_type(), Compile::AliasIdxRaw);
4302 Node* buffer = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw);
4303
4304 // Convert the store obj pointer to an int prior to doing math on it
4305 // Must use ctrl to prevent "integerized oop" existing across safepoint
4306 Node* cast = __ CastPX(__ ctrl(), adr);
4307
4308 // Divide pointer by card size
4309 Node* card_offset = __ URShiftX( cast, __ ConI(CardTableModRefBS::card_shift) );
4310
4311 // Combine card table base and card offset
4312 Node* card_adr = __ AddP(no_base, byte_map_base_node(), card_offset );
4313
4314 // If we know the value being stored does it cross regions?
4315
4316 if (val != NULL) {
4317 // Does the store cause us to cross regions?
4318
4319 // Should be able to do an unsigned compare of region_size instead of
4320 // and extra shift. Do we have an unsigned compare??
4321 // Node* region_size = __ ConI(1 << HeapRegion::LogOfHRGrainBytes);
4322 Node* xor_res = __ URShiftX ( __ XorX( cast, __ CastPX(__ ctrl(), val)), __ ConI(HeapRegion::LogOfHRGrainBytes));
4323
4324 // if (xor_res == 0) same region so skip
4325 __ if_then(xor_res, BoolTest::ne, zeroX); {
4326
4327 // No barrier if we are storing a NULL
4328 __ if_then(val, BoolTest::ne, null(), unlikely); {
4329
4330 // Ok must mark the card if not already dirty
4331
4332 // load the original value of the card
4333 Node* card_val = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw);
4334
4335 __ if_then(card_val, BoolTest::ne, young_card); {
4336 sync_kit(ideal);
4337 // Use Op_MemBarVolatile to achieve the effect of a StoreLoad barrier.
4338 insert_mem_bar(Op_MemBarVolatile, oop_store);
4339 __ sync_kit(this);
4340
4341 Node* card_val_reload = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw);
4342 __ if_then(card_val_reload, BoolTest::ne, dirty_card); {
4343 g1_mark_card(ideal, card_adr, oop_store, alias_idx, index, index_adr, buffer, tf);
4344 } __ end_if();
4345 } __ end_if();
4346 } __ end_if();
4347 } __ end_if();
4348 } else {
4349 // The Object.clone() intrinsic uses this path if !ReduceInitialCardMarks.
4350 // We don't need a barrier here if the destination is a newly allocated object
4351 // in Eden. Otherwise, GC verification breaks because we assume that cards in Eden
4352 // are set to 'g1_young_gen' (see G1SATBCardTableModRefBS::verify_g1_young_region()).
4353 assert(!use_ReduceInitialCardMarks(), "can only happen with card marking");
4354 Node* card_val = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw);
4355 __ if_then(card_val, BoolTest::ne, young_card); {
4356 g1_mark_card(ideal, card_adr, oop_store, alias_idx, index, index_adr, buffer, tf);
4357 } __ end_if();
4358 }
4359
4360 // Final sync IdealKit and GraphKit.
4361 final_sync(ideal);
4362 }
4363 #undef __
4364
4365
4366 Node* GraphKit::load_String_length(Node* ctrl, Node* str) {
4367 Node* len = load_array_length(load_String_value(ctrl, str));
4368 Node* coder = load_String_coder(ctrl, str);
4369 // Divide length by 2 if coder is UTF16
4370 return _gvn.transform(new RShiftINode(len, coder));
4371 }
4372
4373 Node* GraphKit::load_String_value(Node* ctrl, Node* str) {
4374 int value_offset = java_lang_String::value_offset_in_bytes();
4375 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4376 false, NULL, 0);
4377 const TypePtr* value_field_type = string_type->add_offset(value_offset);
4378 const TypeAryPtr* value_type = TypeAryPtr::make(TypePtr::NotNull,
4379 TypeAry::make(TypeInt::BYTE, TypeInt::POS),
4380 ciTypeArrayKlass::make(T_BYTE), true, 0);
4381 int value_field_idx = C->get_alias_index(value_field_type);
4382 Node* load = make_load(ctrl, basic_plus_adr(str, str, value_offset),
4383 value_type, T_OBJECT, value_field_idx, MemNode::unordered);
4384 // String.value field is known to be @Stable.
4385 if (UseImplicitStableValues) {
4386 load = cast_array_to_stable(load, value_type);
4387 }
4388 return load;
4389 }
4390
4391 Node* GraphKit::load_String_coder(Node* ctrl, Node* str) {
4392 if (!CompactStrings) {
4393 return intcon(java_lang_String::CODER_UTF16);
4394 }
4395 int coder_offset = java_lang_String::coder_offset_in_bytes();
4396 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4397 false, NULL, 0);
4398 const TypePtr* coder_field_type = string_type->add_offset(coder_offset);
4399 int coder_field_idx = C->get_alias_index(coder_field_type);
4400 return make_load(ctrl, basic_plus_adr(str, str, coder_offset),
4401 TypeInt::BYTE, T_BYTE, coder_field_idx, MemNode::unordered);
4402 }
4403
4404 void GraphKit::store_String_value(Node* ctrl, Node* str, Node* value) {
4405 int value_offset = java_lang_String::value_offset_in_bytes();
4406 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4407 false, NULL, 0);
4408 const TypePtr* value_field_type = string_type->add_offset(value_offset);
4409 store_oop_to_object(ctrl, str, basic_plus_adr(str, value_offset), value_field_type,
4410 value, TypeAryPtr::BYTES, T_OBJECT, MemNode::unordered);
4411 }
4412
4413 void GraphKit::store_String_coder(Node* ctrl, Node* str, Node* value) {
4414 int coder_offset = java_lang_String::coder_offset_in_bytes();
4415 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4416 false, NULL, 0);
4417 const TypePtr* coder_field_type = string_type->add_offset(coder_offset);
4418 int coder_field_idx = C->get_alias_index(coder_field_type);
4419 store_to_memory(ctrl, basic_plus_adr(str, coder_offset),
4420 value, T_BYTE, coder_field_idx, MemNode::unordered);
4421 }
4422
4423 // Capture src and dst memory state with a MergeMemNode
4424 Node* GraphKit::capture_memory(const TypePtr* src_type, const TypePtr* dst_type) {
4425 if (src_type == dst_type) {
4426 // Types are equal, we don't need a MergeMemNode
4427 return memory(src_type);
4428 }
4429 MergeMemNode* merge = MergeMemNode::make(map()->memory());
4430 record_for_igvn(merge); // fold it up later, if possible
4431 int src_idx = C->get_alias_index(src_type);
4432 int dst_idx = C->get_alias_index(dst_type);
4433 merge->set_memory_at(src_idx, memory(src_idx));
4434 merge->set_memory_at(dst_idx, memory(dst_idx));
4435 return merge;
4436 }
4437
4438 Node* GraphKit::compress_string(Node* src, const TypeAryPtr* src_type, Node* dst, Node* count) {
4439 assert(Matcher::match_rule_supported(Op_StrCompressedCopy), "Intrinsic not supported");
4440 assert(src_type == TypeAryPtr::BYTES || src_type == TypeAryPtr::CHARS, "invalid source type");
4441 // If input and output memory types differ, capture both states to preserve
4442 // the dependency between preceding and subsequent loads/stores.
4443 // For example, the following program:
4444 // StoreB
4445 // compress_string
4446 // LoadB
4447 // has this memory graph (use->def):
4448 // LoadB -> compress_string -> CharMem
4449 // ... -> StoreB -> ByteMem
4450 // The intrinsic hides the dependency between LoadB and StoreB, causing
4451 // the load to read from memory not containing the result of the StoreB.
4452 // The correct memory graph should look like this:
4453 // LoadB -> compress_string -> MergeMem(CharMem, StoreB(ByteMem))
4454 Node* mem = capture_memory(src_type, TypeAryPtr::BYTES);
4455 StrCompressedCopyNode* str = new StrCompressedCopyNode(control(), mem, src, dst, count);
4456 Node* res_mem = _gvn.transform(new SCMemProjNode(str));
4457 set_memory(res_mem, TypeAryPtr::BYTES);
4458 return str;
4459 }
4460
4461 void GraphKit::inflate_string(Node* src, Node* dst, const TypeAryPtr* dst_type, Node* count) {
4462 assert(Matcher::match_rule_supported(Op_StrInflatedCopy), "Intrinsic not supported");
4463 assert(dst_type == TypeAryPtr::BYTES || dst_type == TypeAryPtr::CHARS, "invalid dest type");
4464 // Capture src and dst memory (see comment in 'compress_string').
4465 Node* mem = capture_memory(TypeAryPtr::BYTES, dst_type);
4466 StrInflatedCopyNode* str = new StrInflatedCopyNode(control(), mem, src, dst, count);
4467 set_memory(_gvn.transform(str), dst_type);
4468 }
4469
4470 void GraphKit::inflate_string_slow(Node* src, Node* dst, Node* start, Node* count) {
4471 /**
4472 * int i_char = start;
4473 * for (int i_byte = 0; i_byte < count; i_byte++) {
4474 * dst[i_char++] = (char)(src[i_byte] & 0xff);
4475 * }
4476 */
4477 add_predicate();
4478 RegionNode* head = new RegionNode(3);
4479 head->init_req(1, control());
4480 gvn().set_type(head, Type::CONTROL);
4481 record_for_igvn(head);
4482
4483 Node* i_byte = new PhiNode(head, TypeInt::INT);
4484 i_byte->init_req(1, intcon(0));
4485 gvn().set_type(i_byte, TypeInt::INT);
4486 record_for_igvn(i_byte);
4487
4488 Node* i_char = new PhiNode(head, TypeInt::INT);
4489 i_char->init_req(1, start);
4490 gvn().set_type(i_char, TypeInt::INT);
4491 record_for_igvn(i_char);
4492
4493 Node* mem = PhiNode::make(head, memory(TypeAryPtr::BYTES), Type::MEMORY, TypeAryPtr::BYTES);
4494 gvn().set_type(mem, Type::MEMORY);
4495 record_for_igvn(mem);
4496 set_control(head);
4497 set_memory(mem, TypeAryPtr::BYTES);
4498 Node* ch = load_array_element(control(), src, i_byte, TypeAryPtr::BYTES);
4499 Node* st = store_to_memory(control(), array_element_address(dst, i_char, T_BYTE),
4500 AndI(ch, intcon(0xff)), T_CHAR, TypeAryPtr::BYTES, MemNode::unordered,
4501 false, false, true /* mismatched */);
4502
4503 IfNode* iff = create_and_map_if(head, Bool(CmpI(i_byte, count), BoolTest::lt), PROB_FAIR, COUNT_UNKNOWN);
4504 head->init_req(2, IfTrue(iff));
4505 mem->init_req(2, st);
4506 i_byte->init_req(2, AddI(i_byte, intcon(1)));
4507 i_char->init_req(2, AddI(i_char, intcon(2)));
4508
4509 set_control(IfFalse(iff));
4510 set_memory(st, TypeAryPtr::BYTES);
4511 }
4512
4513 Node* GraphKit::make_constant_from_field(ciField* field, Node* obj) {
4514 if (!field->is_constant()) {
4515 return NULL; // Field not marked as constant.
4516 }
4517 ciInstance* holder = NULL;
4518 if (!field->is_static()) {
4519 ciObject* const_oop = obj->bottom_type()->is_oopptr()->const_oop();
4520 if (const_oop != NULL && const_oop->is_instance()) {
4521 holder = const_oop->as_instance();
4522 }
4523 }
4524 const Type* con_type = Type::make_constant_from_field(field, holder, field->layout_type(),
4525 /*is_unsigned_load=*/false);
4526 if (con_type != NULL) {
4527 return makecon(con_type);
4528 }
4529 return NULL;
4530 }
4531
4532 Node* GraphKit::cast_array_to_stable(Node* ary, const TypeAryPtr* ary_type) {
4533 // Reify the property as a CastPP node in Ideal graph to comply with monotonicity
4534 // assumption of CCP analysis.
4535 return _gvn.transform(new CastPPNode(ary, ary_type->cast_to_stable(true)));
4536 }