1 /*
2 * Copyright (c) 2001, 2017, 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 }
1112 #endif //ASSERT
1113
1114 return true;
1115 }
1116
1117
1118
1119 //------------------------------basic_plus_adr---------------------------------
1120 Node* GraphKit::basic_plus_adr(Node* base, Node* ptr, Node* offset) {
1121 // short-circuit a common case
1122 if (offset == intcon(0)) return ptr;
1123 return _gvn.transform( new AddPNode(base, ptr, offset) );
1124 }
1125
1126 Node* GraphKit::ConvI2L(Node* offset) {
1127 // short-circuit a common case
1128 jint offset_con = find_int_con(offset, Type::OffsetBot);
1129 if (offset_con != Type::OffsetBot) {
1130 return longcon((jlong) offset_con);
1131 }
1132 return _gvn.transform( new ConvI2LNode(offset));
1133 }
1134
1135 Node* GraphKit::ConvI2UL(Node* offset) {
1136 juint offset_con = (juint) find_int_con(offset, Type::OffsetBot);
1137 if (offset_con != (juint) Type::OffsetBot) {
1138 return longcon((julong) offset_con);
1139 }
1140 Node* conv = _gvn.transform( new ConvI2LNode(offset));
1141 Node* mask = _gvn.transform(ConLNode::make((julong) max_juint));
1142 return _gvn.transform( new AndLNode(conv, mask) );
1143 }
1144
1145 Node* GraphKit::ConvL2I(Node* offset) {
1146 // short-circuit a common case
1147 jlong offset_con = find_long_con(offset, (jlong)Type::OffsetBot);
1148 if (offset_con != (jlong)Type::OffsetBot) {
1149 return intcon((int) offset_con);
1150 }
1151 return _gvn.transform( new ConvL2INode(offset));
1152 }
1153
1154 //-------------------------load_object_klass-----------------------------------
1155 Node* GraphKit::load_object_klass(Node* obj) {
1156 // Special-case a fresh allocation to avoid building nodes:
1157 Node* akls = AllocateNode::Ideal_klass(obj, &_gvn);
1158 if (akls != NULL) return akls;
1159 Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes());
1160 return _gvn.transform(LoadKlassNode::make(_gvn, NULL, immutable_memory(), k_adr, TypeInstPtr::KLASS));
1161 }
1162
1163 //-------------------------load_array_length-----------------------------------
1164 Node* GraphKit::load_array_length(Node* array) {
1165 // Special-case a fresh allocation to avoid building nodes:
1166 AllocateArrayNode* alloc = AllocateArrayNode::Ideal_array_allocation(array, &_gvn);
1167 Node *alen;
1168 if (alloc == NULL) {
1169 Node *r_adr = basic_plus_adr(array, arrayOopDesc::length_offset_in_bytes());
1170 alen = _gvn.transform( new LoadRangeNode(0, immutable_memory(), r_adr, TypeInt::POS));
1171 } else {
1172 alen = alloc->Ideal_length();
1173 Node* ccast = alloc->make_ideal_length(_gvn.type(array)->is_oopptr(), &_gvn);
1174 if (ccast != alen) {
1175 alen = _gvn.transform(ccast);
1176 }
1177 }
1178 return alen;
1179 }
1180
1181 //------------------------------do_null_check----------------------------------
1182 // Helper function to do a NULL pointer check. Returned value is
1183 // the incoming address with NULL casted away. You are allowed to use the
1184 // not-null value only if you are control dependent on the test.
1185 #ifndef PRODUCT
1186 extern int explicit_null_checks_inserted,
1187 explicit_null_checks_elided;
1188 #endif
1189 Node* GraphKit::null_check_common(Node* value, BasicType type,
1190 // optional arguments for variations:
1191 bool assert_null,
1192 Node* *null_control,
1193 bool speculative) {
1194 assert(!assert_null || null_control == NULL, "not both at once");
1195 if (stopped()) return top();
1196 NOT_PRODUCT(explicit_null_checks_inserted++);
1197
1198 // Construct NULL check
1199 Node *chk = NULL;
1200 switch(type) {
1201 case T_LONG : chk = new CmpLNode(value, _gvn.zerocon(T_LONG)); break;
1202 case T_INT : chk = new CmpINode(value, _gvn.intcon(0)); break;
1203 case T_ARRAY : // fall through
1204 type = T_OBJECT; // simplify further tests
1205 case T_OBJECT : {
1206 const Type *t = _gvn.type( value );
1207
1208 const TypeOopPtr* tp = t->isa_oopptr();
1209 if (tp != NULL && tp->klass() != NULL && !tp->klass()->is_loaded()
1210 // Only for do_null_check, not any of its siblings:
1211 && !assert_null && null_control == NULL) {
1212 // Usually, any field access or invocation on an unloaded oop type
1213 // will simply fail to link, since the statically linked class is
1214 // likely also to be unloaded. However, in -Xcomp mode, sometimes
1215 // the static class is loaded but the sharper oop type is not.
1216 // Rather than checking for this obscure case in lots of places,
1217 // we simply observe that a null check on an unloaded class
1218 // will always be followed by a nonsense operation, so we
1219 // can just issue the uncommon trap here.
1220 // Our access to the unloaded class will only be correct
1221 // after it has been loaded and initialized, which requires
1222 // a trip through the interpreter.
1223 #ifndef PRODUCT
1224 if (WizardMode) { tty->print("Null check of unloaded "); tp->klass()->print(); tty->cr(); }
1225 #endif
1226 uncommon_trap(Deoptimization::Reason_unloaded,
1227 Deoptimization::Action_reinterpret,
1228 tp->klass(), "!loaded");
1229 return top();
1230 }
1231
1232 if (assert_null) {
1233 // See if the type is contained in NULL_PTR.
1234 // If so, then the value is already null.
1235 if (t->higher_equal(TypePtr::NULL_PTR)) {
1236 NOT_PRODUCT(explicit_null_checks_elided++);
1237 return value; // Elided null assert quickly!
1238 }
1239 } else {
1240 // See if mixing in the NULL pointer changes type.
1241 // If so, then the NULL pointer was not allowed in the original
1242 // type. In other words, "value" was not-null.
1243 if (t->meet(TypePtr::NULL_PTR) != t->remove_speculative()) {
1244 // same as: if (!TypePtr::NULL_PTR->higher_equal(t)) ...
1245 NOT_PRODUCT(explicit_null_checks_elided++);
1246 return value; // Elided null check quickly!
1247 }
1248 }
1249 chk = new CmpPNode( value, null() );
1250 break;
1251 }
1252
1253 default:
1254 fatal("unexpected type: %s", type2name(type));
1255 }
1256 assert(chk != NULL, "sanity check");
1257 chk = _gvn.transform(chk);
1258
1259 BoolTest::mask btest = assert_null ? BoolTest::eq : BoolTest::ne;
1260 BoolNode *btst = new BoolNode( chk, btest);
1261 Node *tst = _gvn.transform( btst );
1262
1263 //-----------
1264 // if peephole optimizations occurred, a prior test existed.
1265 // If a prior test existed, maybe it dominates as we can avoid this test.
1266 if (tst != btst && type == T_OBJECT) {
1267 // At this point we want to scan up the CFG to see if we can
1268 // find an identical test (and so avoid this test altogether).
1269 Node *cfg = control();
1270 int depth = 0;
1271 while( depth < 16 ) { // Limit search depth for speed
1272 if( cfg->Opcode() == Op_IfTrue &&
1273 cfg->in(0)->in(1) == tst ) {
1274 // Found prior test. Use "cast_not_null" to construct an identical
1275 // CastPP (and hence hash to) as already exists for the prior test.
1276 // Return that casted value.
1277 if (assert_null) {
1278 replace_in_map(value, null());
1279 return null(); // do not issue the redundant test
1280 }
1281 Node *oldcontrol = control();
1282 set_control(cfg);
1283 Node *res = cast_not_null(value);
1284 set_control(oldcontrol);
1285 NOT_PRODUCT(explicit_null_checks_elided++);
1286 return res;
1287 }
1288 cfg = IfNode::up_one_dom(cfg, /*linear_only=*/ true);
1289 if (cfg == NULL) break; // Quit at region nodes
1290 depth++;
1291 }
1292 }
1293
1294 //-----------
1295 // Branch to failure if null
1296 float ok_prob = PROB_MAX; // a priori estimate: nulls never happen
1297 Deoptimization::DeoptReason reason;
1298 if (assert_null) {
1299 reason = Deoptimization::reason_null_assert(speculative);
1300 } else if (type == T_OBJECT) {
1301 reason = Deoptimization::reason_null_check(speculative);
1302 } else {
1303 reason = Deoptimization::Reason_div0_check;
1304 }
1305 // %%% Since Reason_unhandled is not recorded on a per-bytecode basis,
1306 // ciMethodData::has_trap_at will return a conservative -1 if any
1307 // must-be-null assertion has failed. This could cause performance
1308 // problems for a method after its first do_null_assert failure.
1309 // Consider using 'Reason_class_check' instead?
1310
1311 // To cause an implicit null check, we set the not-null probability
1312 // to the maximum (PROB_MAX). For an explicit check the probability
1313 // is set to a smaller value.
1314 if (null_control != NULL || too_many_traps(reason)) {
1315 // probability is less likely
1316 ok_prob = PROB_LIKELY_MAG(3);
1317 } else if (!assert_null &&
1318 (ImplicitNullCheckThreshold > 0) &&
1319 method() != NULL &&
1320 (method()->method_data()->trap_count(reason)
1321 >= (uint)ImplicitNullCheckThreshold)) {
1322 ok_prob = PROB_LIKELY_MAG(3);
1323 }
1324
1325 if (null_control != NULL) {
1326 IfNode* iff = create_and_map_if(control(), tst, ok_prob, COUNT_UNKNOWN);
1327 Node* null_true = _gvn.transform( new IfFalseNode(iff));
1328 set_control( _gvn.transform( new IfTrueNode(iff)));
1329 #ifndef PRODUCT
1330 if (null_true == top()) {
1331 explicit_null_checks_elided++;
1332 }
1333 #endif
1334 (*null_control) = null_true;
1335 } else {
1336 BuildCutout unless(this, tst, ok_prob);
1337 // Check for optimizer eliding test at parse time
1338 if (stopped()) {
1339 // Failure not possible; do not bother making uncommon trap.
1340 NOT_PRODUCT(explicit_null_checks_elided++);
1341 } else if (assert_null) {
1342 uncommon_trap(reason,
1343 Deoptimization::Action_make_not_entrant,
1344 NULL, "assert_null");
1345 } else {
1346 replace_in_map(value, zerocon(type));
1347 builtin_throw(reason);
1348 }
1349 }
1350
1351 // Must throw exception, fall-thru not possible?
1352 if (stopped()) {
1353 return top(); // No result
1354 }
1355
1356 if (assert_null) {
1357 // Cast obj to null on this path.
1358 replace_in_map(value, zerocon(type));
1359 return zerocon(type);
1360 }
1361
1362 // Cast obj to not-null on this path, if there is no null_control.
1363 // (If there is a null_control, a non-null value may come back to haunt us.)
1364 if (type == T_OBJECT) {
1365 Node* cast = cast_not_null(value, false);
1366 if (null_control == NULL || (*null_control) == top())
1367 replace_in_map(value, cast);
1368 value = cast;
1369 }
1370
1371 return value;
1372 }
1373
1374
1375 //------------------------------cast_not_null----------------------------------
1376 // Cast obj to not-null on this path
1377 Node* GraphKit::cast_not_null(Node* obj, bool do_replace_in_map) {
1378 const Type *t = _gvn.type(obj);
1379 const Type *t_not_null = t->join_speculative(TypePtr::NOTNULL);
1380 // Object is already not-null?
1381 if( t == t_not_null ) return obj;
1382
1383 Node *cast = new CastPPNode(obj,t_not_null);
1384 cast->init_req(0, control());
1385 cast = _gvn.transform( cast );
1386
1387 // Scan for instances of 'obj' in the current JVM mapping.
1388 // These instances are known to be not-null after the test.
1389 if (do_replace_in_map)
1390 replace_in_map(obj, cast);
1391
1392 return cast; // Return casted value
1393 }
1394
1395 // Sometimes in intrinsics, we implicitly know an object is not null
1396 // (there's no actual null check) so we can cast it to not null. In
1397 // the course of optimizations, the input to the cast can become null.
1398 // In that case that data path will die and we need the control path
1399 // to become dead as well to keep the graph consistent. So we have to
1400 // add a check for null for which one branch can't be taken. It uses
1401 // an Opaque4 node that will cause the check to be removed after loop
1402 // opts so the test goes away and the compiled code doesn't execute a
1403 // useless check.
1404 Node* GraphKit::must_be_not_null(Node* value, bool do_replace_in_map) {
1405 Node* chk = _gvn.transform(new CmpPNode(value, null()));
1406 Node *tst = _gvn.transform(new BoolNode(chk, BoolTest::ne));
1407 Node* opaq = _gvn.transform(new Opaque4Node(C, tst, intcon(1)));
1408 IfNode *iff = new IfNode(control(), opaq, PROB_MAX, COUNT_UNKNOWN);
1409 _gvn.set_type(iff, iff->Value(&_gvn));
1410 Node *if_f = _gvn.transform(new IfFalseNode(iff));
1411 Node *frame = _gvn.transform(new ParmNode(C->start(), TypeFunc::FramePtr));
1412 Node *halt = _gvn.transform(new HaltNode(if_f, frame));
1413 C->root()->add_req(halt);
1414 Node *if_t = _gvn.transform(new IfTrueNode(iff));
1415 set_control(if_t);
1416 return cast_not_null(value, do_replace_in_map);
1417 }
1418
1419
1420 //--------------------------replace_in_map-------------------------------------
1421 void GraphKit::replace_in_map(Node* old, Node* neww) {
1422 if (old == neww) {
1423 return;
1424 }
1425
1426 map()->replace_edge(old, neww);
1427
1428 // Note: This operation potentially replaces any edge
1429 // on the map. This includes locals, stack, and monitors
1430 // of the current (innermost) JVM state.
1431
1432 // don't let inconsistent types from profiling escape this
1433 // method
1434
1435 const Type* told = _gvn.type(old);
1436 const Type* tnew = _gvn.type(neww);
1437
1438 if (!tnew->higher_equal(told)) {
1439 return;
1440 }
1441
1442 map()->record_replaced_node(old, neww);
1443 }
1444
1445
1446 //=============================================================================
1447 //--------------------------------memory---------------------------------------
1448 Node* GraphKit::memory(uint alias_idx) {
1449 MergeMemNode* mem = merged_memory();
1450 Node* p = mem->memory_at(alias_idx);
1451 _gvn.set_type(p, Type::MEMORY); // must be mapped
1452 return p;
1453 }
1454
1455 //-----------------------------reset_memory------------------------------------
1456 Node* GraphKit::reset_memory() {
1457 Node* mem = map()->memory();
1458 // do not use this node for any more parsing!
1459 debug_only( map()->set_memory((Node*)NULL) );
1460 return _gvn.transform( mem );
1461 }
1462
1463 //------------------------------set_all_memory---------------------------------
1464 void GraphKit::set_all_memory(Node* newmem) {
1465 Node* mergemem = MergeMemNode::make(newmem);
1466 gvn().set_type_bottom(mergemem);
1467 map()->set_memory(mergemem);
1468 }
1469
1470 //------------------------------set_all_memory_call----------------------------
1471 void GraphKit::set_all_memory_call(Node* call, bool separate_io_proj) {
1472 Node* newmem = _gvn.transform( new ProjNode(call, TypeFunc::Memory, separate_io_proj) );
1473 set_all_memory(newmem);
1474 }
1475
1476 //=============================================================================
1477 //
1478 // parser factory methods for MemNodes
1479 //
1480 // These are layered on top of the factory methods in LoadNode and StoreNode,
1481 // and integrate with the parser's memory state and _gvn engine.
1482 //
1483
1484 // factory methods in "int adr_idx"
1485 Node* GraphKit::make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
1486 int adr_idx,
1487 MemNode::MemOrd mo,
1488 LoadNode::ControlDependency control_dependency,
1489 bool require_atomic_access,
1490 bool unaligned,
1491 bool mismatched) {
1492 assert(adr_idx != Compile::AliasIdxTop, "use other make_load factory" );
1493 const TypePtr* adr_type = NULL; // debug-mode-only argument
1494 debug_only(adr_type = C->get_adr_type(adr_idx));
1495 Node* mem = memory(adr_idx);
1496 Node* ld;
1497 if (require_atomic_access && bt == T_LONG) {
1498 ld = LoadLNode::make_atomic(ctl, mem, adr, adr_type, t, mo, control_dependency, unaligned, mismatched);
1499 } else if (require_atomic_access && bt == T_DOUBLE) {
1500 ld = LoadDNode::make_atomic(ctl, mem, adr, adr_type, t, mo, control_dependency, unaligned, mismatched);
1501 } else {
1502 ld = LoadNode::make(_gvn, ctl, mem, adr, adr_type, t, bt, mo, control_dependency, unaligned, mismatched);
1503 }
1504 ld = _gvn.transform(ld);
1505 if (((bt == T_OBJECT) && C->do_escape_analysis()) || C->eliminate_boxing()) {
1506 // Improve graph before escape analysis and boxing elimination.
1507 record_for_igvn(ld);
1508 }
1509 return ld;
1510 }
1511
1512 Node* GraphKit::store_to_memory(Node* ctl, Node* adr, Node *val, BasicType bt,
1513 int adr_idx,
1514 MemNode::MemOrd mo,
1515 bool require_atomic_access,
1516 bool unaligned,
1517 bool mismatched) {
1518 assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1519 const TypePtr* adr_type = NULL;
1520 debug_only(adr_type = C->get_adr_type(adr_idx));
1521 Node *mem = memory(adr_idx);
1522 Node* st;
1523 if (require_atomic_access && bt == T_LONG) {
1524 st = StoreLNode::make_atomic(ctl, mem, adr, adr_type, val, mo);
1525 } else if (require_atomic_access && bt == T_DOUBLE) {
1526 st = StoreDNode::make_atomic(ctl, mem, adr, adr_type, val, mo);
1527 } else {
1528 st = StoreNode::make(_gvn, ctl, mem, adr, adr_type, val, bt, mo);
1529 }
1530 if (unaligned) {
1531 st->as_Store()->set_unaligned_access();
1532 }
1533 if (mismatched) {
1534 st->as_Store()->set_mismatched_access();
1535 }
1536 st = _gvn.transform(st);
1537 set_memory(st, adr_idx);
1538 // Back-to-back stores can only remove intermediate store with DU info
1539 // so push on worklist for optimizer.
1540 if (mem->req() > MemNode::Address && adr == mem->in(MemNode::Address))
1541 record_for_igvn(st);
1542
1543 return st;
1544 }
1545
1546
1547 void GraphKit::pre_barrier(bool do_load,
1548 Node* ctl,
1549 Node* obj,
1550 Node* adr,
1551 uint adr_idx,
1552 Node* val,
1553 const TypeOopPtr* val_type,
1554 Node* pre_val,
1555 BasicType bt) {
1556
1557 BarrierSet* bs = Universe::heap()->barrier_set();
1558 set_control(ctl);
1559 switch (bs->kind()) {
1560 case BarrierSet::G1SATBCTLogging:
1561 g1_write_barrier_pre(do_load, obj, adr, adr_idx, val, val_type, pre_val, bt);
1562 break;
1563
1564 case BarrierSet::CardTableForRS:
1565 case BarrierSet::CardTableExtension:
1566 case BarrierSet::ModRef:
1567 break;
1568
1569 default :
1570 ShouldNotReachHere();
1571
1572 }
1573 }
1574
1575 bool GraphKit::can_move_pre_barrier() const {
1576 BarrierSet* bs = Universe::heap()->barrier_set();
1577 switch (bs->kind()) {
1578 case BarrierSet::G1SATBCTLogging:
1579 return true; // Can move it if no safepoint
1580
1581 case BarrierSet::CardTableForRS:
1582 case BarrierSet::CardTableExtension:
1583 case BarrierSet::ModRef:
1584 return true; // There is no pre-barrier
1585
1586 default :
1587 ShouldNotReachHere();
1588 }
1589 return false;
1590 }
1591
1592 void GraphKit::post_barrier(Node* ctl,
1593 Node* store,
1594 Node* obj,
1595 Node* adr,
1596 uint adr_idx,
1597 Node* val,
1598 BasicType bt,
1599 bool use_precise) {
1600 BarrierSet* bs = Universe::heap()->barrier_set();
1601 set_control(ctl);
1602 switch (bs->kind()) {
1603 case BarrierSet::G1SATBCTLogging:
1604 g1_write_barrier_post(store, obj, adr, adr_idx, val, bt, use_precise);
1605 break;
1606
1607 case BarrierSet::CardTableForRS:
1608 case BarrierSet::CardTableExtension:
1609 write_barrier_post(store, obj, adr, adr_idx, val, use_precise);
1610 break;
1611
1612 case BarrierSet::ModRef:
1613 break;
1614
1615 default :
1616 ShouldNotReachHere();
1617
1618 }
1619 }
1620
1621 Node* GraphKit::store_oop(Node* ctl,
1622 Node* obj,
1623 Node* adr,
1624 const TypePtr* adr_type,
1625 Node* val,
1626 const TypeOopPtr* val_type,
1627 BasicType bt,
1628 bool use_precise,
1629 MemNode::MemOrd mo,
1630 bool mismatched) {
1631 // Transformation of a value which could be NULL pointer (CastPP #NULL)
1632 // could be delayed during Parse (for example, in adjust_map_after_if()).
1633 // Execute transformation here to avoid barrier generation in such case.
1634 if (_gvn.type(val) == TypePtr::NULL_PTR)
1635 val = _gvn.makecon(TypePtr::NULL_PTR);
1636
1637 set_control(ctl);
1638 if (stopped()) return top(); // Dead path ?
1639
1640 assert(bt == T_OBJECT, "sanity");
1641 assert(val != NULL, "not dead path");
1642 uint adr_idx = C->get_alias_index(adr_type);
1643 assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1644
1645 pre_barrier(true /* do_load */,
1646 control(), obj, adr, adr_idx, val, val_type,
1647 NULL /* pre_val */,
1648 bt);
1649
1650 Node* store = store_to_memory(control(), adr, val, bt, adr_idx, mo, mismatched);
1651 post_barrier(control(), store, obj, adr, adr_idx, val, bt, use_precise);
1652 return store;
1653 }
1654
1655 // Could be an array or object we don't know at compile time (unsafe ref.)
1656 Node* GraphKit::store_oop_to_unknown(Node* ctl,
1657 Node* obj, // containing obj
1658 Node* adr, // actual adress to store val at
1659 const TypePtr* adr_type,
1660 Node* val,
1661 BasicType bt,
1662 MemNode::MemOrd mo,
1663 bool mismatched) {
1664 Compile::AliasType* at = C->alias_type(adr_type);
1665 const TypeOopPtr* val_type = NULL;
1666 if (adr_type->isa_instptr()) {
1667 if (at->field() != NULL) {
1668 // known field. This code is a copy of the do_put_xxx logic.
1669 ciField* field = at->field();
1670 if (!field->type()->is_loaded()) {
1671 val_type = TypeInstPtr::BOTTOM;
1672 } else {
1673 val_type = TypeOopPtr::make_from_klass(field->type()->as_klass());
1674 }
1675 }
1676 } else if (adr_type->isa_aryptr()) {
1677 val_type = adr_type->is_aryptr()->elem()->make_oopptr();
1678 }
1679 if (val_type == NULL) {
1680 val_type = TypeInstPtr::BOTTOM;
1681 }
1682 return store_oop(ctl, obj, adr, adr_type, val, val_type, bt, true, mo, mismatched);
1683 }
1684
1685
1686 //-------------------------array_element_address-------------------------
1687 Node* GraphKit::array_element_address(Node* ary, Node* idx, BasicType elembt,
1688 const TypeInt* sizetype, Node* ctrl) {
1689 uint shift = exact_log2(type2aelembytes(elembt));
1690 uint header = arrayOopDesc::base_offset_in_bytes(elembt);
1691
1692 // short-circuit a common case (saves lots of confusing waste motion)
1693 jint idx_con = find_int_con(idx, -1);
1694 if (idx_con >= 0) {
1695 intptr_t offset = header + ((intptr_t)idx_con << shift);
1696 return basic_plus_adr(ary, offset);
1697 }
1698
1699 // must be correct type for alignment purposes
1700 Node* base = basic_plus_adr(ary, header);
1701 idx = Compile::conv_I2X_index(&_gvn, idx, sizetype, ctrl);
1702 Node* scale = _gvn.transform( new LShiftXNode(idx, intcon(shift)) );
1703 return basic_plus_adr(ary, base, scale);
1704 }
1705
1706 //-------------------------load_array_element-------------------------
1707 Node* GraphKit::load_array_element(Node* ctl, Node* ary, Node* idx, const TypeAryPtr* arytype) {
1708 const Type* elemtype = arytype->elem();
1709 BasicType elembt = elemtype->array_element_basic_type();
1710 Node* adr = array_element_address(ary, idx, elembt, arytype->size());
1711 if (elembt == T_NARROWOOP) {
1712 elembt = T_OBJECT; // To satisfy switch in LoadNode::make()
1713 }
1714 Node* ld = make_load(ctl, adr, elemtype, elembt, arytype, MemNode::unordered);
1715 return ld;
1716 }
1717
1718 //-------------------------set_arguments_for_java_call-------------------------
1719 // Arguments (pre-popped from the stack) are taken from the JVMS.
1720 void GraphKit::set_arguments_for_java_call(CallJavaNode* call) {
1721 // Add the call arguments:
1722 uint nargs = call->method()->arg_size();
1723 for (uint i = 0; i < nargs; i++) {
1724 Node* arg = argument(i);
1725 call->init_req(i + TypeFunc::Parms, arg);
1726 }
1727 }
1728
1729 //---------------------------set_edges_for_java_call---------------------------
1730 // Connect a newly created call into the current JVMS.
1731 // A return value node (if any) is returned from set_edges_for_java_call.
1732 void GraphKit::set_edges_for_java_call(CallJavaNode* call, bool must_throw, bool separate_io_proj) {
1733
1734 // Add the predefined inputs:
1735 call->init_req( TypeFunc::Control, control() );
1736 call->init_req( TypeFunc::I_O , i_o() );
1737 call->init_req( TypeFunc::Memory , reset_memory() );
1738 call->init_req( TypeFunc::FramePtr, frameptr() );
1739 call->init_req( TypeFunc::ReturnAdr, top() );
1740
1741 add_safepoint_edges(call, must_throw);
1742
1743 Node* xcall = _gvn.transform(call);
1744
1745 if (xcall == top()) {
1746 set_control(top());
1747 return;
1748 }
1749 assert(xcall == call, "call identity is stable");
1750
1751 // Re-use the current map to produce the result.
1752
1753 set_control(_gvn.transform(new ProjNode(call, TypeFunc::Control)));
1754 set_i_o( _gvn.transform(new ProjNode(call, TypeFunc::I_O , separate_io_proj)));
1755 set_all_memory_call(xcall, separate_io_proj);
1756
1757 //return xcall; // no need, caller already has it
1758 }
1759
1760 Node* GraphKit::set_results_for_java_call(CallJavaNode* call, bool separate_io_proj) {
1761 if (stopped()) return top(); // maybe the call folded up?
1762
1763 // Capture the return value, if any.
1764 Node* ret;
1765 if (call->method() == NULL ||
1766 call->method()->return_type()->basic_type() == T_VOID)
1767 ret = top();
1768 else ret = _gvn.transform(new ProjNode(call, TypeFunc::Parms));
1769
1770 // Note: Since any out-of-line call can produce an exception,
1771 // we always insert an I_O projection from the call into the result.
1772
1773 make_slow_call_ex(call, env()->Throwable_klass(), separate_io_proj);
1774
1775 if (separate_io_proj) {
1776 // The caller requested separate projections be used by the fall
1777 // through and exceptional paths, so replace the projections for
1778 // the fall through path.
1779 set_i_o(_gvn.transform( new ProjNode(call, TypeFunc::I_O) ));
1780 set_all_memory(_gvn.transform( new ProjNode(call, TypeFunc::Memory) ));
1781 }
1782 return ret;
1783 }
1784
1785 //--------------------set_predefined_input_for_runtime_call--------------------
1786 // Reading and setting the memory state is way conservative here.
1787 // The real problem is that I am not doing real Type analysis on memory,
1788 // so I cannot distinguish card mark stores from other stores. Across a GC
1789 // point the Store Barrier and the card mark memory has to agree. I cannot
1790 // have a card mark store and its barrier split across the GC point from
1791 // either above or below. Here I get that to happen by reading ALL of memory.
1792 // A better answer would be to separate out card marks from other memory.
1793 // For now, return the input memory state, so that it can be reused
1794 // after the call, if this call has restricted memory effects.
1795 Node* GraphKit::set_predefined_input_for_runtime_call(SafePointNode* call) {
1796 // Set fixed predefined input arguments
1797 Node* memory = reset_memory();
1798 call->init_req( TypeFunc::Control, control() );
1799 call->init_req( TypeFunc::I_O, top() ); // does no i/o
1800 call->init_req( TypeFunc::Memory, memory ); // may gc ptrs
1801 call->init_req( TypeFunc::FramePtr, frameptr() );
1802 call->init_req( TypeFunc::ReturnAdr, top() );
1803 return memory;
1804 }
1805
1806 //-------------------set_predefined_output_for_runtime_call--------------------
1807 // Set control and memory (not i_o) from the call.
1808 // If keep_mem is not NULL, use it for the output state,
1809 // except for the RawPtr output of the call, if hook_mem is TypeRawPtr::BOTTOM.
1810 // If hook_mem is NULL, this call produces no memory effects at all.
1811 // If hook_mem is a Java-visible memory slice (such as arraycopy operands),
1812 // then only that memory slice is taken from the call.
1813 // In the last case, we must put an appropriate memory barrier before
1814 // the call, so as to create the correct anti-dependencies on loads
1815 // preceding the call.
1816 void GraphKit::set_predefined_output_for_runtime_call(Node* call,
1817 Node* keep_mem,
1818 const TypePtr* hook_mem) {
1819 // no i/o
1820 set_control(_gvn.transform( new ProjNode(call,TypeFunc::Control) ));
1821 if (keep_mem) {
1822 // First clone the existing memory state
1823 set_all_memory(keep_mem);
1824 if (hook_mem != NULL) {
1825 // Make memory for the call
1826 Node* mem = _gvn.transform( new ProjNode(call, TypeFunc::Memory) );
1827 // Set the RawPtr memory state only. This covers all the heap top/GC stuff
1828 // We also use hook_mem to extract specific effects from arraycopy stubs.
1829 set_memory(mem, hook_mem);
1830 }
1831 // ...else the call has NO memory effects.
1832
1833 // Make sure the call advertises its memory effects precisely.
1834 // This lets us build accurate anti-dependences in gcm.cpp.
1835 assert(C->alias_type(call->adr_type()) == C->alias_type(hook_mem),
1836 "call node must be constructed correctly");
1837 } else {
1838 assert(hook_mem == NULL, "");
1839 // This is not a "slow path" call; all memory comes from the call.
1840 set_all_memory_call(call);
1841 }
1842 }
1843
1844
1845 // Replace the call with the current state of the kit.
1846 void GraphKit::replace_call(CallNode* call, Node* result, bool do_replaced_nodes) {
1847 JVMState* ejvms = NULL;
1848 if (has_exceptions()) {
1849 ejvms = transfer_exceptions_into_jvms();
1850 }
1851
1852 ReplacedNodes replaced_nodes = map()->replaced_nodes();
1853 ReplacedNodes replaced_nodes_exception;
1854 Node* ex_ctl = top();
1855
1856 SafePointNode* final_state = stop();
1857
1858 // Find all the needed outputs of this call
1859 CallProjections callprojs;
1860 call->extract_projections(&callprojs, true);
1861
1862 Node* init_mem = call->in(TypeFunc::Memory);
1863 Node* final_mem = final_state->in(TypeFunc::Memory);
1864 Node* final_ctl = final_state->in(TypeFunc::Control);
1865 Node* final_io = final_state->in(TypeFunc::I_O);
1866
1867 // Replace all the old call edges with the edges from the inlining result
1868 if (callprojs.fallthrough_catchproj != NULL) {
1869 C->gvn_replace_by(callprojs.fallthrough_catchproj, final_ctl);
1870 }
1871 if (callprojs.fallthrough_memproj != NULL) {
1872 if (final_mem->is_MergeMem()) {
1873 // Parser's exits MergeMem was not transformed but may be optimized
1874 final_mem = _gvn.transform(final_mem);
1875 }
1876 C->gvn_replace_by(callprojs.fallthrough_memproj, final_mem);
1877 }
1878 if (callprojs.fallthrough_ioproj != NULL) {
1879 C->gvn_replace_by(callprojs.fallthrough_ioproj, final_io);
1880 }
1881
1882 // Replace the result with the new result if it exists and is used
1883 if (callprojs.resproj != NULL && result != NULL) {
1884 C->gvn_replace_by(callprojs.resproj, result);
1885 }
1886
1887 if (ejvms == NULL) {
1888 // No exception edges to simply kill off those paths
1889 if (callprojs.catchall_catchproj != NULL) {
1890 C->gvn_replace_by(callprojs.catchall_catchproj, C->top());
1891 }
1892 if (callprojs.catchall_memproj != NULL) {
1893 C->gvn_replace_by(callprojs.catchall_memproj, C->top());
1894 }
1895 if (callprojs.catchall_ioproj != NULL) {
1896 C->gvn_replace_by(callprojs.catchall_ioproj, C->top());
1897 }
1898 // Replace the old exception object with top
1899 if (callprojs.exobj != NULL) {
1900 C->gvn_replace_by(callprojs.exobj, C->top());
1901 }
1902 } else {
1903 GraphKit ekit(ejvms);
1904
1905 // Load my combined exception state into the kit, with all phis transformed:
1906 SafePointNode* ex_map = ekit.combine_and_pop_all_exception_states();
1907 replaced_nodes_exception = ex_map->replaced_nodes();
1908
1909 Node* ex_oop = ekit.use_exception_state(ex_map);
1910
1911 if (callprojs.catchall_catchproj != NULL) {
1912 C->gvn_replace_by(callprojs.catchall_catchproj, ekit.control());
1913 ex_ctl = ekit.control();
1914 }
1915 if (callprojs.catchall_memproj != NULL) {
1916 C->gvn_replace_by(callprojs.catchall_memproj, ekit.reset_memory());
1917 }
1918 if (callprojs.catchall_ioproj != NULL) {
1919 C->gvn_replace_by(callprojs.catchall_ioproj, ekit.i_o());
1920 }
1921
1922 // Replace the old exception object with the newly created one
1923 if (callprojs.exobj != NULL) {
1924 C->gvn_replace_by(callprojs.exobj, ex_oop);
1925 }
1926 }
1927
1928 // Disconnect the call from the graph
1929 call->disconnect_inputs(NULL, C);
1930 C->gvn_replace_by(call, C->top());
1931
1932 // Clean up any MergeMems that feed other MergeMems since the
1933 // optimizer doesn't like that.
1934 if (final_mem->is_MergeMem()) {
1935 Node_List wl;
1936 for (SimpleDUIterator i(final_mem); i.has_next(); i.next()) {
1937 Node* m = i.get();
1938 if (m->is_MergeMem() && !wl.contains(m)) {
1939 wl.push(m);
1940 }
1941 }
1942 while (wl.size() > 0) {
1943 _gvn.transform(wl.pop());
1944 }
1945 }
1946
1947 if (callprojs.fallthrough_catchproj != NULL && !final_ctl->is_top() && do_replaced_nodes) {
1948 replaced_nodes.apply(C, final_ctl);
1949 }
1950 if (!ex_ctl->is_top() && do_replaced_nodes) {
1951 replaced_nodes_exception.apply(C, ex_ctl);
1952 }
1953 }
1954
1955
1956 //------------------------------increment_counter------------------------------
1957 // for statistics: increment a VM counter by 1
1958
1959 void GraphKit::increment_counter(address counter_addr) {
1960 Node* adr1 = makecon(TypeRawPtr::make(counter_addr));
1961 increment_counter(adr1);
1962 }
1963
1964 void GraphKit::increment_counter(Node* counter_addr) {
1965 int adr_type = Compile::AliasIdxRaw;
1966 Node* ctrl = control();
1967 Node* cnt = make_load(ctrl, counter_addr, TypeInt::INT, T_INT, adr_type, MemNode::unordered);
1968 Node* incr = _gvn.transform(new AddINode(cnt, _gvn.intcon(1)));
1969 store_to_memory(ctrl, counter_addr, incr, T_INT, adr_type, MemNode::unordered);
1970 }
1971
1972
1973 //------------------------------uncommon_trap----------------------------------
1974 // Bail out to the interpreter in mid-method. Implemented by calling the
1975 // uncommon_trap blob. This helper function inserts a runtime call with the
1976 // right debug info.
1977 void GraphKit::uncommon_trap(int trap_request,
1978 ciKlass* klass, const char* comment,
1979 bool must_throw,
1980 bool keep_exact_action) {
1981 if (failing()) stop();
1982 if (stopped()) return; // trap reachable?
1983
1984 // Note: If ProfileTraps is true, and if a deopt. actually
1985 // occurs here, the runtime will make sure an MDO exists. There is
1986 // no need to call method()->ensure_method_data() at this point.
1987
1988 // Set the stack pointer to the right value for reexecution:
1989 set_sp(reexecute_sp());
1990
1991 #ifdef ASSERT
1992 if (!must_throw) {
1993 // Make sure the stack has at least enough depth to execute
1994 // the current bytecode.
1995 int inputs, ignored_depth;
1996 if (compute_stack_effects(inputs, ignored_depth)) {
1997 assert(sp() >= inputs, "must have enough JVMS stack to execute %s: sp=%d, inputs=%d",
1998 Bytecodes::name(java_bc()), sp(), inputs);
1999 }
2000 }
2001 #endif
2002
2003 Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
2004 Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
2005
2006 switch (action) {
2007 case Deoptimization::Action_maybe_recompile:
2008 case Deoptimization::Action_reinterpret:
2009 // Temporary fix for 6529811 to allow virtual calls to be sure they
2010 // get the chance to go from mono->bi->mega
2011 if (!keep_exact_action &&
2012 Deoptimization::trap_request_index(trap_request) < 0 &&
2013 too_many_recompiles(reason)) {
2014 // This BCI is causing too many recompilations.
2015 if (C->log() != NULL) {
2016 C->log()->elem("observe that='trap_action_change' reason='%s' from='%s' to='none'",
2017 Deoptimization::trap_reason_name(reason),
2018 Deoptimization::trap_action_name(action));
2019 }
2020 action = Deoptimization::Action_none;
2021 trap_request = Deoptimization::make_trap_request(reason, action);
2022 } else {
2023 C->set_trap_can_recompile(true);
2024 }
2025 break;
2026 case Deoptimization::Action_make_not_entrant:
2027 C->set_trap_can_recompile(true);
2028 break;
2029 case Deoptimization::Action_none:
2030 case Deoptimization::Action_make_not_compilable:
2031 break;
2032 default:
2033 #ifdef ASSERT
2034 fatal("unknown action %d: %s", action, Deoptimization::trap_action_name(action));
2035 #endif
2036 break;
2037 }
2038
2039 if (TraceOptoParse) {
2040 char buf[100];
2041 tty->print_cr("Uncommon trap %s at bci:%d",
2042 Deoptimization::format_trap_request(buf, sizeof(buf),
2043 trap_request), bci());
2044 }
2045
2046 CompileLog* log = C->log();
2047 if (log != NULL) {
2048 int kid = (klass == NULL)? -1: log->identify(klass);
2049 log->begin_elem("uncommon_trap bci='%d'", bci());
2050 char buf[100];
2051 log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf),
2052 trap_request));
2053 if (kid >= 0) log->print(" klass='%d'", kid);
2054 if (comment != NULL) log->print(" comment='%s'", comment);
2055 log->end_elem();
2056 }
2057
2058 // Make sure any guarding test views this path as very unlikely
2059 Node *i0 = control()->in(0);
2060 if (i0 != NULL && i0->is_If()) { // Found a guarding if test?
2061 IfNode *iff = i0->as_If();
2062 float f = iff->_prob; // Get prob
2063 if (control()->Opcode() == Op_IfTrue) {
2064 if (f > PROB_UNLIKELY_MAG(4))
2065 iff->_prob = PROB_MIN;
2066 } else {
2067 if (f < PROB_LIKELY_MAG(4))
2068 iff->_prob = PROB_MAX;
2069 }
2070 }
2071
2072 // Clear out dead values from the debug info.
2073 kill_dead_locals();
2074
2075 // Now insert the uncommon trap subroutine call
2076 address call_addr = SharedRuntime::uncommon_trap_blob()->entry_point();
2077 const TypePtr* no_memory_effects = NULL;
2078 // Pass the index of the class to be loaded
2079 Node* call = make_runtime_call(RC_NO_LEAF | RC_UNCOMMON |
2080 (must_throw ? RC_MUST_THROW : 0),
2081 OptoRuntime::uncommon_trap_Type(),
2082 call_addr, "uncommon_trap", no_memory_effects,
2083 intcon(trap_request));
2084 assert(call->as_CallStaticJava()->uncommon_trap_request() == trap_request,
2085 "must extract request correctly from the graph");
2086 assert(trap_request != 0, "zero value reserved by uncommon_trap_request");
2087
2088 call->set_req(TypeFunc::ReturnAdr, returnadr());
2089 // The debug info is the only real input to this call.
2090
2091 // Halt-and-catch fire here. The above call should never return!
2092 HaltNode* halt = new HaltNode(control(), frameptr());
2093 _gvn.set_type_bottom(halt);
2094 root()->add_req(halt);
2095
2096 stop_and_kill_map();
2097 }
2098
2099
2100 //--------------------------just_allocated_object------------------------------
2101 // Report the object that was just allocated.
2102 // It must be the case that there are no intervening safepoints.
2103 // We use this to determine if an object is so "fresh" that
2104 // it does not require card marks.
2105 Node* GraphKit::just_allocated_object(Node* current_control) {
2106 if (C->recent_alloc_ctl() == current_control)
2107 return C->recent_alloc_obj();
2108 return NULL;
2109 }
2110
2111
2112 void GraphKit::round_double_arguments(ciMethod* dest_method) {
2113 // (Note: TypeFunc::make has a cache that makes this fast.)
2114 const TypeFunc* tf = TypeFunc::make(dest_method);
2115 int nargs = tf->domain()->cnt() - TypeFunc::Parms;
2116 for (int j = 0; j < nargs; j++) {
2117 const Type *targ = tf->domain()->field_at(j + TypeFunc::Parms);
2118 if( targ->basic_type() == T_DOUBLE ) {
2119 // If any parameters are doubles, they must be rounded before
2120 // the call, dstore_rounding does gvn.transform
2121 Node *arg = argument(j);
2122 arg = dstore_rounding(arg);
2123 set_argument(j, arg);
2124 }
2125 }
2126 }
2127
2128 /**
2129 * Record profiling data exact_kls for Node n with the type system so
2130 * that it can propagate it (speculation)
2131 *
2132 * @param n node that the type applies to
2133 * @param exact_kls type from profiling
2134 * @param maybe_null did profiling see null?
2135 *
2136 * @return node with improved type
2137 */
2138 Node* GraphKit::record_profile_for_speculation(Node* n, ciKlass* exact_kls, ProfilePtrKind ptr_kind) {
2139 const Type* current_type = _gvn.type(n);
2140 assert(UseTypeSpeculation, "type speculation must be on");
2141
2142 const TypePtr* speculative = current_type->speculative();
2143
2144 // Should the klass from the profile be recorded in the speculative type?
2145 if (current_type->would_improve_type(exact_kls, jvms()->depth())) {
2146 const TypeKlassPtr* tklass = TypeKlassPtr::make(exact_kls);
2147 const TypeOopPtr* xtype = tklass->as_instance_type();
2148 assert(xtype->klass_is_exact(), "Should be exact");
2149 // Any reason to believe n is not null (from this profiling or a previous one)?
2150 assert(ptr_kind != ProfileAlwaysNull, "impossible here");
2151 const TypePtr* ptr = (ptr_kind == ProfileMaybeNull && current_type->speculative_maybe_null()) ? TypePtr::BOTTOM : TypePtr::NOTNULL;
2152 // record the new speculative type's depth
2153 speculative = xtype->cast_to_ptr_type(ptr->ptr())->is_ptr();
2154 speculative = speculative->with_inline_depth(jvms()->depth());
2155 } else if (current_type->would_improve_ptr(ptr_kind)) {
2156 // Profiling report that null was never seen so we can change the
2157 // speculative type to non null ptr.
2158 if (ptr_kind == ProfileAlwaysNull) {
2159 speculative = TypePtr::NULL_PTR;
2160 } else {
2161 assert(ptr_kind == ProfileNeverNull, "nothing else is an improvement");
2162 const TypePtr* ptr = TypePtr::NOTNULL;
2163 if (speculative != NULL) {
2164 speculative = speculative->cast_to_ptr_type(ptr->ptr())->is_ptr();
2165 } else {
2166 speculative = ptr;
2167 }
2168 }
2169 }
2170
2171 if (speculative != current_type->speculative()) {
2172 // Build a type with a speculative type (what we think we know
2173 // about the type but will need a guard when we use it)
2174 const TypeOopPtr* spec_type = TypeOopPtr::make(TypePtr::BotPTR, Type::OffsetBot, TypeOopPtr::InstanceBot, speculative);
2175 // We're changing the type, we need a new CheckCast node to carry
2176 // the new type. The new type depends on the control: what
2177 // profiling tells us is only valid from here as far as we can
2178 // tell.
2179 Node* cast = new CheckCastPPNode(control(), n, current_type->remove_speculative()->join_speculative(spec_type));
2180 cast = _gvn.transform(cast);
2181 replace_in_map(n, cast);
2182 n = cast;
2183 }
2184
2185 return n;
2186 }
2187
2188 /**
2189 * Record profiling data from receiver profiling at an invoke with the
2190 * type system so that it can propagate it (speculation)
2191 *
2192 * @param n receiver node
2193 *
2194 * @return node with improved type
2195 */
2196 Node* GraphKit::record_profiled_receiver_for_speculation(Node* n) {
2197 if (!UseTypeSpeculation) {
2198 return n;
2199 }
2200 ciKlass* exact_kls = profile_has_unique_klass();
2201 ProfilePtrKind ptr_kind = ProfileMaybeNull;
2202 if ((java_bc() == Bytecodes::_checkcast ||
2203 java_bc() == Bytecodes::_instanceof ||
2204 java_bc() == Bytecodes::_aastore) &&
2205 method()->method_data()->is_mature()) {
2206 ciProfileData* data = method()->method_data()->bci_to_data(bci());
2207 if (data != NULL) {
2208 if (!data->as_BitData()->null_seen()) {
2209 ptr_kind = ProfileNeverNull;
2210 } else {
2211 assert(data->is_ReceiverTypeData(), "bad profile data type");
2212 ciReceiverTypeData* call = (ciReceiverTypeData*)data->as_ReceiverTypeData();
2213 uint i = 0;
2214 for (; i < call->row_limit(); i++) {
2215 ciKlass* receiver = call->receiver(i);
2216 if (receiver != NULL) {
2217 break;
2218 }
2219 }
2220 ptr_kind = (i == call->row_limit()) ? ProfileAlwaysNull : ProfileMaybeNull;
2221 }
2222 }
2223 }
2224 return record_profile_for_speculation(n, exact_kls, ptr_kind);
2225 }
2226
2227 /**
2228 * Record profiling data from argument profiling at an invoke with the
2229 * type system so that it can propagate it (speculation)
2230 *
2231 * @param dest_method target method for the call
2232 * @param bc what invoke bytecode is this?
2233 */
2234 void GraphKit::record_profiled_arguments_for_speculation(ciMethod* dest_method, Bytecodes::Code bc) {
2235 if (!UseTypeSpeculation) {
2236 return;
2237 }
2238 const TypeFunc* tf = TypeFunc::make(dest_method);
2239 int nargs = tf->domain()->cnt() - TypeFunc::Parms;
2240 int skip = Bytecodes::has_receiver(bc) ? 1 : 0;
2241 for (int j = skip, i = 0; j < nargs && i < TypeProfileArgsLimit; j++) {
2242 const Type *targ = tf->domain()->field_at(j + TypeFunc::Parms);
2243 if (targ->basic_type() == T_OBJECT || targ->basic_type() == T_ARRAY) {
2244 ProfilePtrKind ptr_kind = ProfileMaybeNull;
2245 ciKlass* better_type = NULL;
2246 if (method()->argument_profiled_type(bci(), i, better_type, ptr_kind)) {
2247 record_profile_for_speculation(argument(j), better_type, ptr_kind);
2248 }
2249 i++;
2250 }
2251 }
2252 }
2253
2254 /**
2255 * Record profiling data from parameter profiling at an invoke with
2256 * the type system so that it can propagate it (speculation)
2257 */
2258 void GraphKit::record_profiled_parameters_for_speculation() {
2259 if (!UseTypeSpeculation) {
2260 return;
2261 }
2262 for (int i = 0, j = 0; i < method()->arg_size() ; i++) {
2263 if (_gvn.type(local(i))->isa_oopptr()) {
2264 ProfilePtrKind ptr_kind = ProfileMaybeNull;
2265 ciKlass* better_type = NULL;
2266 if (method()->parameter_profiled_type(j, better_type, ptr_kind)) {
2267 record_profile_for_speculation(local(i), better_type, ptr_kind);
2268 }
2269 j++;
2270 }
2271 }
2272 }
2273
2274 /**
2275 * Record profiling data from return value profiling at an invoke with
2276 * the type system so that it can propagate it (speculation)
2277 */
2278 void GraphKit::record_profiled_return_for_speculation() {
2279 if (!UseTypeSpeculation) {
2280 return;
2281 }
2282 ProfilePtrKind ptr_kind = ProfileMaybeNull;
2283 ciKlass* better_type = NULL;
2284 if (method()->return_profiled_type(bci(), better_type, ptr_kind)) {
2285 // If profiling reports a single type for the return value,
2286 // feed it to the type system so it can propagate it as a
2287 // speculative type
2288 record_profile_for_speculation(stack(sp()-1), better_type, ptr_kind);
2289 }
2290 }
2291
2292 void GraphKit::round_double_result(ciMethod* dest_method) {
2293 // A non-strict method may return a double value which has an extended
2294 // exponent, but this must not be visible in a caller which is 'strict'
2295 // If a strict caller invokes a non-strict callee, round a double result
2296
2297 BasicType result_type = dest_method->return_type()->basic_type();
2298 assert( method() != NULL, "must have caller context");
2299 if( result_type == T_DOUBLE && method()->is_strict() && !dest_method->is_strict() ) {
2300 // Destination method's return value is on top of stack
2301 // dstore_rounding() does gvn.transform
2302 Node *result = pop_pair();
2303 result = dstore_rounding(result);
2304 push_pair(result);
2305 }
2306 }
2307
2308 // rounding for strict float precision conformance
2309 Node* GraphKit::precision_rounding(Node* n) {
2310 return UseStrictFP && _method->flags().is_strict()
2311 && UseSSE == 0 && Matcher::strict_fp_requires_explicit_rounding
2312 ? _gvn.transform( new RoundFloatNode(0, n) )
2313 : n;
2314 }
2315
2316 // rounding for strict double precision conformance
2317 Node* GraphKit::dprecision_rounding(Node *n) {
2318 return UseStrictFP && _method->flags().is_strict()
2319 && UseSSE <= 1 && Matcher::strict_fp_requires_explicit_rounding
2320 ? _gvn.transform( new RoundDoubleNode(0, n) )
2321 : n;
2322 }
2323
2324 // rounding for non-strict double stores
2325 Node* GraphKit::dstore_rounding(Node* n) {
2326 return Matcher::strict_fp_requires_explicit_rounding
2327 && UseSSE <= 1
2328 ? _gvn.transform( new RoundDoubleNode(0, n) )
2329 : n;
2330 }
2331
2332 //=============================================================================
2333 // Generate a fast path/slow path idiom. Graph looks like:
2334 // [foo] indicates that 'foo' is a parameter
2335 //
2336 // [in] NULL
2337 // \ /
2338 // CmpP
2339 // Bool ne
2340 // If
2341 // / \
2342 // True False-<2>
2343 // / |
2344 // / cast_not_null
2345 // Load | | ^
2346 // [fast_test] | |
2347 // gvn to opt_test | |
2348 // / \ | <1>
2349 // True False |
2350 // | \\ |
2351 // [slow_call] \[fast_result]
2352 // Ctl Val \ \
2353 // | \ \
2354 // Catch <1> \ \
2355 // / \ ^ \ \
2356 // Ex No_Ex | \ \
2357 // | \ \ | \ <2> \
2358 // ... \ [slow_res] | | \ [null_result]
2359 // \ \--+--+--- | |
2360 // \ | / \ | /
2361 // --------Region Phi
2362 //
2363 //=============================================================================
2364 // Code is structured as a series of driver functions all called 'do_XXX' that
2365 // call a set of helper functions. Helper functions first, then drivers.
2366
2367 //------------------------------null_check_oop---------------------------------
2368 // Null check oop. Set null-path control into Region in slot 3.
2369 // Make a cast-not-nullness use the other not-null control. Return cast.
2370 Node* GraphKit::null_check_oop(Node* value, Node* *null_control,
2371 bool never_see_null,
2372 bool safe_for_replace,
2373 bool speculative) {
2374 // Initial NULL check taken path
2375 (*null_control) = top();
2376 Node* cast = null_check_common(value, T_OBJECT, false, null_control, speculative);
2377
2378 // Generate uncommon_trap:
2379 if (never_see_null && (*null_control) != top()) {
2380 // If we see an unexpected null at a check-cast we record it and force a
2381 // recompile; the offending check-cast will be compiled to handle NULLs.
2382 // If we see more than one offending BCI, then all checkcasts in the
2383 // method will be compiled to handle NULLs.
2384 PreserveJVMState pjvms(this);
2385 set_control(*null_control);
2386 replace_in_map(value, null());
2387 Deoptimization::DeoptReason reason = Deoptimization::reason_null_check(speculative);
2388 uncommon_trap(reason,
2389 Deoptimization::Action_make_not_entrant);
2390 (*null_control) = top(); // NULL path is dead
2391 }
2392 if ((*null_control) == top() && safe_for_replace) {
2393 replace_in_map(value, cast);
2394 }
2395
2396 // Cast away null-ness on the result
2397 return cast;
2398 }
2399
2400 //------------------------------opt_iff----------------------------------------
2401 // Optimize the fast-check IfNode. Set the fast-path region slot 2.
2402 // Return slow-path control.
2403 Node* GraphKit::opt_iff(Node* region, Node* iff) {
2404 IfNode *opt_iff = _gvn.transform(iff)->as_If();
2405
2406 // Fast path taken; set region slot 2
2407 Node *fast_taken = _gvn.transform( new IfFalseNode(opt_iff) );
2408 region->init_req(2,fast_taken); // Capture fast-control
2409
2410 // Fast path not-taken, i.e. slow path
2411 Node *slow_taken = _gvn.transform( new IfTrueNode(opt_iff) );
2412 return slow_taken;
2413 }
2414
2415 //-----------------------------make_runtime_call-------------------------------
2416 Node* GraphKit::make_runtime_call(int flags,
2417 const TypeFunc* call_type, address call_addr,
2418 const char* call_name,
2419 const TypePtr* adr_type,
2420 // The following parms are all optional.
2421 // The first NULL ends the list.
2422 Node* parm0, Node* parm1,
2423 Node* parm2, Node* parm3,
2424 Node* parm4, Node* parm5,
2425 Node* parm6, Node* parm7) {
2426 // Slow-path call
2427 bool is_leaf = !(flags & RC_NO_LEAF);
2428 bool has_io = (!is_leaf && !(flags & RC_NO_IO));
2429 if (call_name == NULL) {
2430 assert(!is_leaf, "must supply name for leaf");
2431 call_name = OptoRuntime::stub_name(call_addr);
2432 }
2433 CallNode* call;
2434 if (!is_leaf) {
2435 call = new CallStaticJavaNode(call_type, call_addr, call_name,
2436 bci(), adr_type);
2437 } else if (flags & RC_NO_FP) {
2438 call = new CallLeafNoFPNode(call_type, call_addr, call_name, adr_type);
2439 } else {
2440 call = new CallLeafNode(call_type, call_addr, call_name, adr_type);
2441 }
2442
2443 // The following is similar to set_edges_for_java_call,
2444 // except that the memory effects of the call are restricted to AliasIdxRaw.
2445
2446 // Slow path call has no side-effects, uses few values
2447 bool wide_in = !(flags & RC_NARROW_MEM);
2448 bool wide_out = (C->get_alias_index(adr_type) == Compile::AliasIdxBot);
2449
2450 Node* prev_mem = NULL;
2451 if (wide_in) {
2452 prev_mem = set_predefined_input_for_runtime_call(call);
2453 } else {
2454 assert(!wide_out, "narrow in => narrow out");
2455 Node* narrow_mem = memory(adr_type);
2456 prev_mem = reset_memory();
2457 map()->set_memory(narrow_mem);
2458 set_predefined_input_for_runtime_call(call);
2459 }
2460
2461 // Hook each parm in order. Stop looking at the first NULL.
2462 if (parm0 != NULL) { call->init_req(TypeFunc::Parms+0, parm0);
2463 if (parm1 != NULL) { call->init_req(TypeFunc::Parms+1, parm1);
2464 if (parm2 != NULL) { call->init_req(TypeFunc::Parms+2, parm2);
2465 if (parm3 != NULL) { call->init_req(TypeFunc::Parms+3, parm3);
2466 if (parm4 != NULL) { call->init_req(TypeFunc::Parms+4, parm4);
2467 if (parm5 != NULL) { call->init_req(TypeFunc::Parms+5, parm5);
2468 if (parm6 != NULL) { call->init_req(TypeFunc::Parms+6, parm6);
2469 if (parm7 != NULL) { call->init_req(TypeFunc::Parms+7, parm7);
2470 /* close each nested if ===> */ } } } } } } } }
2471 assert(call->in(call->req()-1) != NULL, "must initialize all parms");
2472
2473 if (!is_leaf) {
2474 // Non-leaves can block and take safepoints:
2475 add_safepoint_edges(call, ((flags & RC_MUST_THROW) != 0));
2476 }
2477 // Non-leaves can throw exceptions:
2478 if (has_io) {
2479 call->set_req(TypeFunc::I_O, i_o());
2480 }
2481
2482 if (flags & RC_UNCOMMON) {
2483 // Set the count to a tiny probability. Cf. Estimate_Block_Frequency.
2484 // (An "if" probability corresponds roughly to an unconditional count.
2485 // Sort of.)
2486 call->set_cnt(PROB_UNLIKELY_MAG(4));
2487 }
2488
2489 Node* c = _gvn.transform(call);
2490 assert(c == call, "cannot disappear");
2491
2492 if (wide_out) {
2493 // Slow path call has full side-effects.
2494 set_predefined_output_for_runtime_call(call);
2495 } else {
2496 // Slow path call has few side-effects, and/or sets few values.
2497 set_predefined_output_for_runtime_call(call, prev_mem, adr_type);
2498 }
2499
2500 if (has_io) {
2501 set_i_o(_gvn.transform(new ProjNode(call, TypeFunc::I_O)));
2502 }
2503 return call;
2504
2505 }
2506
2507 //------------------------------merge_memory-----------------------------------
2508 // Merge memory from one path into the current memory state.
2509 void GraphKit::merge_memory(Node* new_mem, Node* region, int new_path) {
2510 for (MergeMemStream mms(merged_memory(), new_mem->as_MergeMem()); mms.next_non_empty2(); ) {
2511 Node* old_slice = mms.force_memory();
2512 Node* new_slice = mms.memory2();
2513 if (old_slice != new_slice) {
2514 PhiNode* phi;
2515 if (old_slice->is_Phi() && old_slice->as_Phi()->region() == region) {
2516 if (mms.is_empty()) {
2517 // clone base memory Phi's inputs for this memory slice
2518 assert(old_slice == mms.base_memory(), "sanity");
2519 phi = PhiNode::make(region, NULL, Type::MEMORY, mms.adr_type(C));
2520 _gvn.set_type(phi, Type::MEMORY);
2521 for (uint i = 1; i < phi->req(); i++) {
2522 phi->init_req(i, old_slice->in(i));
2523 }
2524 } else {
2525 phi = old_slice->as_Phi(); // Phi was generated already
2526 }
2527 } else {
2528 phi = PhiNode::make(region, old_slice, Type::MEMORY, mms.adr_type(C));
2529 _gvn.set_type(phi, Type::MEMORY);
2530 }
2531 phi->set_req(new_path, new_slice);
2532 mms.set_memory(phi);
2533 }
2534 }
2535 }
2536
2537 //------------------------------make_slow_call_ex------------------------------
2538 // Make the exception handler hookups for the slow call
2539 void GraphKit::make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj, bool deoptimize) {
2540 if (stopped()) return;
2541
2542 // Make a catch node with just two handlers: fall-through and catch-all
2543 Node* i_o = _gvn.transform( new ProjNode(call, TypeFunc::I_O, separate_io_proj) );
2544 Node* catc = _gvn.transform( new CatchNode(control(), i_o, 2) );
2545 Node* norm = _gvn.transform( new CatchProjNode(catc, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci) );
2546 Node* excp = _gvn.transform( new CatchProjNode(catc, CatchProjNode::catch_all_index, CatchProjNode::no_handler_bci) );
2547
2548 { PreserveJVMState pjvms(this);
2549 set_control(excp);
2550 set_i_o(i_o);
2551
2552 if (excp != top()) {
2553 if (deoptimize) {
2554 // Deoptimize if an exception is caught. Don't construct exception state in this case.
2555 uncommon_trap(Deoptimization::Reason_unhandled,
2556 Deoptimization::Action_none);
2557 } else {
2558 // Create an exception state also.
2559 // Use an exact type if the caller has specified a specific exception.
2560 const Type* ex_type = TypeOopPtr::make_from_klass_unique(ex_klass)->cast_to_ptr_type(TypePtr::NotNull);
2561 Node* ex_oop = new CreateExNode(ex_type, control(), i_o);
2562 add_exception_state(make_exception_state(_gvn.transform(ex_oop)));
2563 }
2564 }
2565 }
2566
2567 // Get the no-exception control from the CatchNode.
2568 set_control(norm);
2569 }
2570
2571 static IfNode* gen_subtype_check_compare(Node* ctrl, Node* in1, Node* in2, BoolTest::mask test, float p, PhaseGVN* gvn, BasicType bt) {
2572 Node* cmp = NULL;
2573 switch(bt) {
2574 case T_INT: cmp = new CmpINode(in1, in2); break;
2575 case T_ADDRESS: cmp = new CmpPNode(in1, in2); break;
2576 default: fatal("unexpected comparison type %s", type2name(bt));
2577 }
2578 gvn->transform(cmp);
2579 Node* bol = gvn->transform(new BoolNode(cmp, test));
2580 IfNode* iff = new IfNode(ctrl, bol, p, COUNT_UNKNOWN);
2581 gvn->transform(iff);
2582 if (!bol->is_Con()) gvn->record_for_igvn(iff);
2583 return iff;
2584 }
2585
2586
2587 //-------------------------------gen_subtype_check-----------------------------
2588 // Generate a subtyping check. Takes as input the subtype and supertype.
2589 // Returns 2 values: sets the default control() to the true path and returns
2590 // the false path. Only reads invariant memory; sets no (visible) memory.
2591 // The PartialSubtypeCheckNode sets the hidden 1-word cache in the encoding
2592 // but that's not exposed to the optimizer. This call also doesn't take in an
2593 // Object; if you wish to check an Object you need to load the Object's class
2594 // prior to coming here.
2595 Node* Phase::gen_subtype_check(Node* subklass, Node* superklass, Node** ctrl, MergeMemNode* mem, PhaseGVN* gvn) {
2596 Compile* C = gvn->C;
2597
2598 if ((*ctrl)->is_top()) {
2599 return C->top();
2600 }
2601
2602 // Fast check for identical types, perhaps identical constants.
2603 // The types can even be identical non-constants, in cases
2604 // involving Array.newInstance, Object.clone, etc.
2605 if (subklass == superklass)
2606 return C->top(); // false path is dead; no test needed.
2607
2608 if (gvn->type(superklass)->singleton()) {
2609 ciKlass* superk = gvn->type(superklass)->is_klassptr()->klass();
2610 ciKlass* subk = gvn->type(subklass)->is_klassptr()->klass();
2611
2612 // In the common case of an exact superklass, try to fold up the
2613 // test before generating code. You may ask, why not just generate
2614 // the code and then let it fold up? The answer is that the generated
2615 // code will necessarily include null checks, which do not always
2616 // completely fold away. If they are also needless, then they turn
2617 // into a performance loss. Example:
2618 // Foo[] fa = blah(); Foo x = fa[0]; fa[1] = x;
2619 // Here, the type of 'fa' is often exact, so the store check
2620 // of fa[1]=x will fold up, without testing the nullness of x.
2621 switch (C->static_subtype_check(superk, subk)) {
2622 case Compile::SSC_always_false:
2623 {
2624 Node* always_fail = *ctrl;
2625 *ctrl = gvn->C->top();
2626 return always_fail;
2627 }
2628 case Compile::SSC_always_true:
2629 return C->top();
2630 case Compile::SSC_easy_test:
2631 {
2632 // Just do a direct pointer compare and be done.
2633 IfNode* iff = gen_subtype_check_compare(*ctrl, subklass, superklass, BoolTest::eq, PROB_STATIC_FREQUENT, gvn, T_ADDRESS);
2634 *ctrl = gvn->transform(new IfTrueNode(iff));
2635 return gvn->transform(new IfFalseNode(iff));
2636 }
2637 case Compile::SSC_full_test:
2638 break;
2639 default:
2640 ShouldNotReachHere();
2641 }
2642 }
2643
2644 // %%% Possible further optimization: Even if the superklass is not exact,
2645 // if the subklass is the unique subtype of the superklass, the check
2646 // will always succeed. We could leave a dependency behind to ensure this.
2647
2648 // First load the super-klass's check-offset
2649 Node *p1 = gvn->transform(new AddPNode(superklass, superklass, gvn->MakeConX(in_bytes(Klass::super_check_offset_offset()))));
2650 Node* m = mem->memory_at(C->get_alias_index(gvn->type(p1)->is_ptr()));
2651 Node *chk_off = gvn->transform(new LoadINode(NULL, m, p1, gvn->type(p1)->is_ptr(), TypeInt::INT, MemNode::unordered));
2652 int cacheoff_con = in_bytes(Klass::secondary_super_cache_offset());
2653 bool might_be_cache = (gvn->find_int_con(chk_off, cacheoff_con) == cacheoff_con);
2654
2655 // Load from the sub-klass's super-class display list, or a 1-word cache of
2656 // the secondary superclass list, or a failing value with a sentinel offset
2657 // if the super-klass is an interface or exceptionally deep in the Java
2658 // hierarchy and we have to scan the secondary superclass list the hard way.
2659 // Worst-case type is a little odd: NULL is allowed as a result (usually
2660 // klass loads can never produce a NULL).
2661 Node *chk_off_X = chk_off;
2662 #ifdef _LP64
2663 chk_off_X = gvn->transform(new ConvI2LNode(chk_off_X));
2664 #endif
2665 Node *p2 = gvn->transform(new AddPNode(subklass,subklass,chk_off_X));
2666 // For some types like interfaces the following loadKlass is from a 1-word
2667 // cache which is mutable so can't use immutable memory. Other
2668 // types load from the super-class display table which is immutable.
2669 m = mem->memory_at(C->get_alias_index(gvn->type(p2)->is_ptr()));
2670 Node *kmem = might_be_cache ? m : C->immutable_memory();
2671 Node *nkls = gvn->transform(LoadKlassNode::make(*gvn, NULL, kmem, p2, gvn->type(p2)->is_ptr(), TypeKlassPtr::OBJECT_OR_NULL));
2672
2673 // Compile speed common case: ARE a subtype and we canNOT fail
2674 if( superklass == nkls )
2675 return C->top(); // false path is dead; no test needed.
2676
2677 // See if we get an immediate positive hit. Happens roughly 83% of the
2678 // time. Test to see if the value loaded just previously from the subklass
2679 // is exactly the superklass.
2680 IfNode *iff1 = gen_subtype_check_compare(*ctrl, superklass, nkls, BoolTest::eq, PROB_LIKELY(0.83f), gvn, T_ADDRESS);
2681 Node *iftrue1 = gvn->transform( new IfTrueNode (iff1));
2682 *ctrl = gvn->transform(new IfFalseNode(iff1));
2683
2684 // Compile speed common case: Check for being deterministic right now. If
2685 // chk_off is a constant and not equal to cacheoff then we are NOT a
2686 // subklass. In this case we need exactly the 1 test above and we can
2687 // return those results immediately.
2688 if (!might_be_cache) {
2689 Node* not_subtype_ctrl = *ctrl;
2690 *ctrl = iftrue1; // We need exactly the 1 test above
2691 return not_subtype_ctrl;
2692 }
2693
2694 // Gather the various success & failures here
2695 RegionNode *r_ok_subtype = new RegionNode(4);
2696 gvn->record_for_igvn(r_ok_subtype);
2697 RegionNode *r_not_subtype = new RegionNode(3);
2698 gvn->record_for_igvn(r_not_subtype);
2699
2700 r_ok_subtype->init_req(1, iftrue1);
2701
2702 // Check for immediate negative hit. Happens roughly 11% of the time (which
2703 // is roughly 63% of the remaining cases). Test to see if the loaded
2704 // check-offset points into the subklass display list or the 1-element
2705 // cache. If it points to the display (and NOT the cache) and the display
2706 // missed then it's not a subtype.
2707 Node *cacheoff = gvn->intcon(cacheoff_con);
2708 IfNode *iff2 = gen_subtype_check_compare(*ctrl, chk_off, cacheoff, BoolTest::ne, PROB_LIKELY(0.63f), gvn, T_INT);
2709 r_not_subtype->init_req(1, gvn->transform(new IfTrueNode (iff2)));
2710 *ctrl = gvn->transform(new IfFalseNode(iff2));
2711
2712 // Check for self. Very rare to get here, but it is taken 1/3 the time.
2713 // No performance impact (too rare) but allows sharing of secondary arrays
2714 // which has some footprint reduction.
2715 IfNode *iff3 = gen_subtype_check_compare(*ctrl, subklass, superklass, BoolTest::eq, PROB_LIKELY(0.36f), gvn, T_ADDRESS);
2716 r_ok_subtype->init_req(2, gvn->transform(new IfTrueNode(iff3)));
2717 *ctrl = gvn->transform(new IfFalseNode(iff3));
2718
2719 // -- Roads not taken here: --
2720 // We could also have chosen to perform the self-check at the beginning
2721 // of this code sequence, as the assembler does. This would not pay off
2722 // the same way, since the optimizer, unlike the assembler, can perform
2723 // static type analysis to fold away many successful self-checks.
2724 // Non-foldable self checks work better here in second position, because
2725 // the initial primary superclass check subsumes a self-check for most
2726 // types. An exception would be a secondary type like array-of-interface,
2727 // which does not appear in its own primary supertype display.
2728 // Finally, we could have chosen to move the self-check into the
2729 // PartialSubtypeCheckNode, and from there out-of-line in a platform
2730 // dependent manner. But it is worthwhile to have the check here,
2731 // where it can be perhaps be optimized. The cost in code space is
2732 // small (register compare, branch).
2733
2734 // Now do a linear scan of the secondary super-klass array. Again, no real
2735 // performance impact (too rare) but it's gotta be done.
2736 // Since the code is rarely used, there is no penalty for moving it
2737 // out of line, and it can only improve I-cache density.
2738 // The decision to inline or out-of-line this final check is platform
2739 // dependent, and is found in the AD file definition of PartialSubtypeCheck.
2740 Node* psc = gvn->transform(
2741 new PartialSubtypeCheckNode(*ctrl, subklass, superklass));
2742
2743 IfNode *iff4 = gen_subtype_check_compare(*ctrl, psc, gvn->zerocon(T_OBJECT), BoolTest::ne, PROB_FAIR, gvn, T_ADDRESS);
2744 r_not_subtype->init_req(2, gvn->transform(new IfTrueNode (iff4)));
2745 r_ok_subtype ->init_req(3, gvn->transform(new IfFalseNode(iff4)));
2746
2747 // Return false path; set default control to true path.
2748 *ctrl = gvn->transform(r_ok_subtype);
2749 return gvn->transform(r_not_subtype);
2750 }
2751
2752 // Profile-driven exact type check:
2753 Node* GraphKit::type_check_receiver(Node* receiver, ciKlass* klass,
2754 float prob,
2755 Node* *casted_receiver) {
2756 const TypeKlassPtr* tklass = TypeKlassPtr::make(klass);
2757 Node* recv_klass = load_object_klass(receiver);
2758 Node* want_klass = makecon(tklass);
2759 Node* cmp = _gvn.transform( new CmpPNode(recv_klass, want_klass) );
2760 Node* bol = _gvn.transform( new BoolNode(cmp, BoolTest::eq) );
2761 IfNode* iff = create_and_xform_if(control(), bol, prob, COUNT_UNKNOWN);
2762 set_control( _gvn.transform( new IfTrueNode (iff) ));
2763 Node* fail = _gvn.transform( new IfFalseNode(iff) );
2764
2765 const TypeOopPtr* recv_xtype = tklass->as_instance_type();
2766 assert(recv_xtype->klass_is_exact(), "");
2767
2768 // Subsume downstream occurrences of receiver with a cast to
2769 // recv_xtype, since now we know what the type will be.
2770 Node* cast = new CheckCastPPNode(control(), receiver, recv_xtype);
2771 (*casted_receiver) = _gvn.transform(cast);
2772 // (User must make the replace_in_map call.)
2773
2774 return fail;
2775 }
2776
2777
2778 //------------------------------seems_never_null-------------------------------
2779 // Use null_seen information if it is available from the profile.
2780 // If we see an unexpected null at a type check we record it and force a
2781 // recompile; the offending check will be recompiled to handle NULLs.
2782 // If we see several offending BCIs, then all checks in the
2783 // method will be recompiled.
2784 bool GraphKit::seems_never_null(Node* obj, ciProfileData* data, bool& speculating) {
2785 speculating = !_gvn.type(obj)->speculative_maybe_null();
2786 Deoptimization::DeoptReason reason = Deoptimization::reason_null_check(speculating);
2787 if (UncommonNullCast // Cutout for this technique
2788 && obj != null() // And not the -Xcomp stupid case?
2789 && !too_many_traps(reason)
2790 ) {
2791 if (speculating) {
2792 return true;
2793 }
2794 if (data == NULL)
2795 // Edge case: no mature data. Be optimistic here.
2796 return true;
2797 // If the profile has not seen a null, assume it won't happen.
2798 assert(java_bc() == Bytecodes::_checkcast ||
2799 java_bc() == Bytecodes::_instanceof ||
2800 java_bc() == Bytecodes::_aastore, "MDO must collect null_seen bit here");
2801 return !data->as_BitData()->null_seen();
2802 }
2803 speculating = false;
2804 return false;
2805 }
2806
2807 //------------------------maybe_cast_profiled_receiver-------------------------
2808 // If the profile has seen exactly one type, narrow to exactly that type.
2809 // Subsequent type checks will always fold up.
2810 Node* GraphKit::maybe_cast_profiled_receiver(Node* not_null_obj,
2811 ciKlass* require_klass,
2812 ciKlass* spec_klass,
2813 bool safe_for_replace) {
2814 if (!UseTypeProfile || !TypeProfileCasts) return NULL;
2815
2816 Deoptimization::DeoptReason reason = Deoptimization::reason_class_check(spec_klass != NULL);
2817
2818 // Make sure we haven't already deoptimized from this tactic.
2819 if (too_many_traps(reason) || too_many_recompiles(reason))
2820 return NULL;
2821
2822 // (No, this isn't a call, but it's enough like a virtual call
2823 // to use the same ciMethod accessor to get the profile info...)
2824 // If we have a speculative type use it instead of profiling (which
2825 // may not help us)
2826 ciKlass* exact_kls = spec_klass == NULL ? profile_has_unique_klass() : spec_klass;
2827 if (exact_kls != NULL) {// no cast failures here
2828 if (require_klass == NULL ||
2829 C->static_subtype_check(require_klass, exact_kls) == Compile::SSC_always_true) {
2830 // If we narrow the type to match what the type profile sees or
2831 // the speculative type, we can then remove the rest of the
2832 // cast.
2833 // This is a win, even if the exact_kls is very specific,
2834 // because downstream operations, such as method calls,
2835 // will often benefit from the sharper type.
2836 Node* exact_obj = not_null_obj; // will get updated in place...
2837 Node* slow_ctl = type_check_receiver(exact_obj, exact_kls, 1.0,
2838 &exact_obj);
2839 { PreserveJVMState pjvms(this);
2840 set_control(slow_ctl);
2841 uncommon_trap_exact(reason, Deoptimization::Action_maybe_recompile);
2842 }
2843 if (safe_for_replace) {
2844 replace_in_map(not_null_obj, exact_obj);
2845 }
2846 return exact_obj;
2847 }
2848 // assert(ssc == Compile::SSC_always_true)... except maybe the profile lied to us.
2849 }
2850
2851 return NULL;
2852 }
2853
2854 /**
2855 * Cast obj to type and emit guard unless we had too many traps here
2856 * already
2857 *
2858 * @param obj node being casted
2859 * @param type type to cast the node to
2860 * @param not_null true if we know node cannot be null
2861 */
2862 Node* GraphKit::maybe_cast_profiled_obj(Node* obj,
2863 ciKlass* type,
2864 bool not_null) {
2865 if (stopped()) {
2866 return obj;
2867 }
2868
2869 // type == NULL if profiling tells us this object is always null
2870 if (type != NULL) {
2871 Deoptimization::DeoptReason class_reason = Deoptimization::Reason_speculate_class_check;
2872 Deoptimization::DeoptReason null_reason = Deoptimization::Reason_speculate_null_check;
2873
2874 if (!too_many_traps(null_reason) && !too_many_recompiles(null_reason) &&
2875 !too_many_traps(class_reason) &&
2876 !too_many_recompiles(class_reason)) {
2877 Node* not_null_obj = NULL;
2878 // not_null is true if we know the object is not null and
2879 // there's no need for a null check
2880 if (!not_null) {
2881 Node* null_ctl = top();
2882 not_null_obj = null_check_oop(obj, &null_ctl, true, true, true);
2883 assert(null_ctl->is_top(), "no null control here");
2884 } else {
2885 not_null_obj = obj;
2886 }
2887
2888 Node* exact_obj = not_null_obj;
2889 ciKlass* exact_kls = type;
2890 Node* slow_ctl = type_check_receiver(exact_obj, exact_kls, 1.0,
2891 &exact_obj);
2892 {
2893 PreserveJVMState pjvms(this);
2894 set_control(slow_ctl);
2895 uncommon_trap_exact(class_reason, Deoptimization::Action_maybe_recompile);
2896 }
2897 replace_in_map(not_null_obj, exact_obj);
2898 obj = exact_obj;
2899 }
2900 } else {
2901 if (!too_many_traps(Deoptimization::Reason_null_assert) &&
2902 !too_many_recompiles(Deoptimization::Reason_null_assert)) {
2903 Node* exact_obj = null_assert(obj);
2904 replace_in_map(obj, exact_obj);
2905 obj = exact_obj;
2906 }
2907 }
2908 return obj;
2909 }
2910
2911 //-------------------------------gen_instanceof--------------------------------
2912 // Generate an instance-of idiom. Used by both the instance-of bytecode
2913 // and the reflective instance-of call.
2914 Node* GraphKit::gen_instanceof(Node* obj, Node* superklass, bool safe_for_replace) {
2915 kill_dead_locals(); // Benefit all the uncommon traps
2916 assert( !stopped(), "dead parse path should be checked in callers" );
2917 assert(!TypePtr::NULL_PTR->higher_equal(_gvn.type(superklass)->is_klassptr()),
2918 "must check for not-null not-dead klass in callers");
2919
2920 // Make the merge point
2921 enum { _obj_path = 1, _fail_path, _null_path, PATH_LIMIT };
2922 RegionNode* region = new RegionNode(PATH_LIMIT);
2923 Node* phi = new PhiNode(region, TypeInt::BOOL);
2924 C->set_has_split_ifs(true); // Has chance for split-if optimization
2925
2926 ciProfileData* data = NULL;
2927 if (java_bc() == Bytecodes::_instanceof) { // Only for the bytecode
2928 data = method()->method_data()->bci_to_data(bci());
2929 }
2930 bool speculative_not_null = false;
2931 bool never_see_null = (ProfileDynamicTypes // aggressive use of profile
2932 && seems_never_null(obj, data, speculative_not_null));
2933
2934 // Null check; get casted pointer; set region slot 3
2935 Node* null_ctl = top();
2936 Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace, speculative_not_null);
2937
2938 // If not_null_obj is dead, only null-path is taken
2939 if (stopped()) { // Doing instance-of on a NULL?
2940 set_control(null_ctl);
2941 return intcon(0);
2942 }
2943 region->init_req(_null_path, null_ctl);
2944 phi ->init_req(_null_path, intcon(0)); // Set null path value
2945 if (null_ctl == top()) {
2946 // Do this eagerly, so that pattern matches like is_diamond_phi
2947 // will work even during parsing.
2948 assert(_null_path == PATH_LIMIT-1, "delete last");
2949 region->del_req(_null_path);
2950 phi ->del_req(_null_path);
2951 }
2952
2953 // Do we know the type check always succeed?
2954 bool known_statically = false;
2955 if (_gvn.type(superklass)->singleton()) {
2956 ciKlass* superk = _gvn.type(superklass)->is_klassptr()->klass();
2957 ciKlass* subk = _gvn.type(obj)->is_oopptr()->klass();
2958 if (subk != NULL && subk->is_loaded()) {
2959 int static_res = C->static_subtype_check(superk, subk);
2960 known_statically = (static_res == Compile::SSC_always_true || static_res == Compile::SSC_always_false);
2961 }
2962 }
2963
2964 if (!known_statically) {
2965 const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
2966 // We may not have profiling here or it may not help us. If we
2967 // have a speculative type use it to perform an exact cast.
2968 ciKlass* spec_obj_type = obj_type->speculative_type();
2969 if (spec_obj_type != NULL || (ProfileDynamicTypes && data != NULL)) {
2970 Node* cast_obj = maybe_cast_profiled_receiver(not_null_obj, NULL, spec_obj_type, safe_for_replace);
2971 if (stopped()) { // Profile disagrees with this path.
2972 set_control(null_ctl); // Null is the only remaining possibility.
2973 return intcon(0);
2974 }
2975 if (cast_obj != NULL) {
2976 not_null_obj = cast_obj;
2977 }
2978 }
2979 }
2980
2981 // Load the object's klass
2982 Node* obj_klass = load_object_klass(not_null_obj);
2983
2984 // Generate the subtype check
2985 Node* not_subtype_ctrl = gen_subtype_check(obj_klass, superklass);
2986
2987 // Plug in the success path to the general merge in slot 1.
2988 region->init_req(_obj_path, control());
2989 phi ->init_req(_obj_path, intcon(1));
2990
2991 // Plug in the failing path to the general merge in slot 2.
2992 region->init_req(_fail_path, not_subtype_ctrl);
2993 phi ->init_req(_fail_path, intcon(0));
2994
2995 // Return final merged results
2996 set_control( _gvn.transform(region) );
2997 record_for_igvn(region);
2998
2999 // If we know the type check always succeeds then we don't use the
3000 // profiling data at this bytecode. Don't lose it, feed it to the
3001 // type system as a speculative type.
3002 if (safe_for_replace) {
3003 Node* casted_obj = record_profiled_receiver_for_speculation(obj);
3004 replace_in_map(obj, casted_obj);
3005 }
3006
3007 return _gvn.transform(phi);
3008 }
3009
3010 //-------------------------------gen_checkcast---------------------------------
3011 // Generate a checkcast idiom. Used by both the checkcast bytecode and the
3012 // array store bytecode. Stack must be as-if BEFORE doing the bytecode so the
3013 // uncommon-trap paths work. Adjust stack after this call.
3014 // If failure_control is supplied and not null, it is filled in with
3015 // the control edge for the cast failure. Otherwise, an appropriate
3016 // uncommon trap or exception is thrown.
3017 Node* GraphKit::gen_checkcast(Node *obj, Node* superklass,
3018 Node* *failure_control) {
3019 kill_dead_locals(); // Benefit all the uncommon traps
3020 const TypeKlassPtr *tk = _gvn.type(superklass)->is_klassptr();
3021 const Type *toop = TypeOopPtr::make_from_klass(tk->klass());
3022
3023 // Fast cutout: Check the case that the cast is vacuously true.
3024 // This detects the common cases where the test will short-circuit
3025 // away completely. We do this before we perform the null check,
3026 // because if the test is going to turn into zero code, we don't
3027 // want a residual null check left around. (Causes a slowdown,
3028 // for example, in some objArray manipulations, such as a[i]=a[j].)
3029 if (tk->singleton()) {
3030 const TypeOopPtr* objtp = _gvn.type(obj)->isa_oopptr();
3031 if (objtp != NULL && objtp->klass() != NULL) {
3032 switch (C->static_subtype_check(tk->klass(), objtp->klass())) {
3033 case Compile::SSC_always_true:
3034 // If we know the type check always succeed then we don't use
3035 // the profiling data at this bytecode. Don't lose it, feed it
3036 // to the type system as a speculative type.
3037 return record_profiled_receiver_for_speculation(obj);
3038 case Compile::SSC_always_false:
3039 // It needs a null check because a null will *pass* the cast check.
3040 // A non-null value will always produce an exception.
3041 return null_assert(obj);
3042 }
3043 }
3044 }
3045
3046 ciProfileData* data = NULL;
3047 bool safe_for_replace = false;
3048 if (failure_control == NULL) { // use MDO in regular case only
3049 assert(java_bc() == Bytecodes::_aastore ||
3050 java_bc() == Bytecodes::_checkcast,
3051 "interpreter profiles type checks only for these BCs");
3052 data = method()->method_data()->bci_to_data(bci());
3053 safe_for_replace = true;
3054 }
3055
3056 // Make the merge point
3057 enum { _obj_path = 1, _null_path, PATH_LIMIT };
3058 RegionNode* region = new RegionNode(PATH_LIMIT);
3059 Node* phi = new PhiNode(region, toop);
3060 C->set_has_split_ifs(true); // Has chance for split-if optimization
3061
3062 // Use null-cast information if it is available
3063 bool speculative_not_null = false;
3064 bool never_see_null = ((failure_control == NULL) // regular case only
3065 && seems_never_null(obj, data, speculative_not_null));
3066
3067 // Null check; get casted pointer; set region slot 3
3068 Node* null_ctl = top();
3069 Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace, speculative_not_null);
3070
3071 // If not_null_obj is dead, only null-path is taken
3072 if (stopped()) { // Doing instance-of on a NULL?
3073 set_control(null_ctl);
3074 return null();
3075 }
3076 region->init_req(_null_path, null_ctl);
3077 phi ->init_req(_null_path, null()); // Set null path value
3078 if (null_ctl == top()) {
3079 // Do this eagerly, so that pattern matches like is_diamond_phi
3080 // will work even during parsing.
3081 assert(_null_path == PATH_LIMIT-1, "delete last");
3082 region->del_req(_null_path);
3083 phi ->del_req(_null_path);
3084 }
3085
3086 Node* cast_obj = NULL;
3087 if (tk->klass_is_exact()) {
3088 // The following optimization tries to statically cast the speculative type of the object
3089 // (for example obtained during profiling) to the type of the superklass and then do a
3090 // dynamic check that the type of the object is what we expect. To work correctly
3091 // for checkcast and aastore the type of superklass should be exact.
3092 const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
3093 // We may not have profiling here or it may not help us. If we have
3094 // a speculative type use it to perform an exact cast.
3095 ciKlass* spec_obj_type = obj_type->speculative_type();
3096 if (spec_obj_type != NULL || data != NULL) {
3097 cast_obj = maybe_cast_profiled_receiver(not_null_obj, tk->klass(), spec_obj_type, safe_for_replace);
3098 if (cast_obj != NULL) {
3099 if (failure_control != NULL) // failure is now impossible
3100 (*failure_control) = top();
3101 // adjust the type of the phi to the exact klass:
3102 phi->raise_bottom_type(_gvn.type(cast_obj)->meet_speculative(TypePtr::NULL_PTR));
3103 }
3104 }
3105 }
3106
3107 if (cast_obj == NULL) {
3108 // Load the object's klass
3109 Node* obj_klass = load_object_klass(not_null_obj);
3110
3111 // Generate the subtype check
3112 Node* not_subtype_ctrl = gen_subtype_check( obj_klass, superklass );
3113
3114 // Plug in success path into the merge
3115 cast_obj = _gvn.transform(new CheckCastPPNode(control(), not_null_obj, toop));
3116 // Failure path ends in uncommon trap (or may be dead - failure impossible)
3117 if (failure_control == NULL) {
3118 if (not_subtype_ctrl != top()) { // If failure is possible
3119 PreserveJVMState pjvms(this);
3120 set_control(not_subtype_ctrl);
3121 builtin_throw(Deoptimization::Reason_class_check, obj_klass);
3122 }
3123 } else {
3124 (*failure_control) = not_subtype_ctrl;
3125 }
3126 }
3127
3128 region->init_req(_obj_path, control());
3129 phi ->init_req(_obj_path, cast_obj);
3130
3131 // A merge of NULL or Casted-NotNull obj
3132 Node* res = _gvn.transform(phi);
3133
3134 // Note I do NOT always 'replace_in_map(obj,result)' here.
3135 // if( tk->klass()->can_be_primary_super() )
3136 // This means that if I successfully store an Object into an array-of-String
3137 // I 'forget' that the Object is really now known to be a String. I have to
3138 // do this because we don't have true union types for interfaces - if I store
3139 // a Baz into an array-of-Interface and then tell the optimizer it's an
3140 // Interface, I forget that it's also a Baz and cannot do Baz-like field
3141 // references to it. FIX THIS WHEN UNION TYPES APPEAR!
3142 // replace_in_map( obj, res );
3143
3144 // Return final merged results
3145 set_control( _gvn.transform(region) );
3146 record_for_igvn(region);
3147
3148 return record_profiled_receiver_for_speculation(res);
3149 }
3150
3151 //------------------------------next_monitor-----------------------------------
3152 // What number should be given to the next monitor?
3153 int GraphKit::next_monitor() {
3154 int current = jvms()->monitor_depth()* C->sync_stack_slots();
3155 int next = current + C->sync_stack_slots();
3156 // Keep the toplevel high water mark current:
3157 if (C->fixed_slots() < next) C->set_fixed_slots(next);
3158 return current;
3159 }
3160
3161 //------------------------------insert_mem_bar---------------------------------
3162 // Memory barrier to avoid floating things around
3163 // The membar serves as a pinch point between both control and all memory slices.
3164 Node* GraphKit::insert_mem_bar(int opcode, Node* precedent) {
3165 MemBarNode* mb = MemBarNode::make(C, opcode, Compile::AliasIdxBot, precedent);
3166 mb->init_req(TypeFunc::Control, control());
3167 mb->init_req(TypeFunc::Memory, reset_memory());
3168 Node* membar = _gvn.transform(mb);
3169 set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control)));
3170 set_all_memory_call(membar);
3171 return membar;
3172 }
3173
3174 //-------------------------insert_mem_bar_volatile----------------------------
3175 // Memory barrier to avoid floating things around
3176 // The membar serves as a pinch point between both control and memory(alias_idx).
3177 // If you want to make a pinch point on all memory slices, do not use this
3178 // function (even with AliasIdxBot); use insert_mem_bar() instead.
3179 Node* GraphKit::insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent) {
3180 // When Parse::do_put_xxx updates a volatile field, it appends a series
3181 // of MemBarVolatile nodes, one for *each* volatile field alias category.
3182 // The first membar is on the same memory slice as the field store opcode.
3183 // This forces the membar to follow the store. (Bug 6500685 broke this.)
3184 // All the other membars (for other volatile slices, including AliasIdxBot,
3185 // which stands for all unknown volatile slices) are control-dependent
3186 // on the first membar. This prevents later volatile loads or stores
3187 // from sliding up past the just-emitted store.
3188
3189 MemBarNode* mb = MemBarNode::make(C, opcode, alias_idx, precedent);
3190 mb->set_req(TypeFunc::Control,control());
3191 if (alias_idx == Compile::AliasIdxBot) {
3192 mb->set_req(TypeFunc::Memory, merged_memory()->base_memory());
3193 } else {
3194 assert(!(opcode == Op_Initialize && alias_idx != Compile::AliasIdxRaw), "fix caller");
3195 mb->set_req(TypeFunc::Memory, memory(alias_idx));
3196 }
3197 Node* membar = _gvn.transform(mb);
3198 set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control)));
3199 if (alias_idx == Compile::AliasIdxBot) {
3200 merged_memory()->set_base_memory(_gvn.transform(new ProjNode(membar, TypeFunc::Memory)));
3201 } else {
3202 set_memory(_gvn.transform(new ProjNode(membar, TypeFunc::Memory)),alias_idx);
3203 }
3204 return membar;
3205 }
3206
3207 //------------------------------shared_lock------------------------------------
3208 // Emit locking code.
3209 FastLockNode* GraphKit::shared_lock(Node* obj) {
3210 // bci is either a monitorenter bc or InvocationEntryBci
3211 // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3212 assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3213
3214 if( !GenerateSynchronizationCode )
3215 return NULL; // Not locking things?
3216 if (stopped()) // Dead monitor?
3217 return NULL;
3218
3219 assert(dead_locals_are_killed(), "should kill locals before sync. point");
3220
3221 // Box the stack location
3222 Node* box = _gvn.transform(new BoxLockNode(next_monitor()));
3223 Node* mem = reset_memory();
3224
3225 FastLockNode * flock = _gvn.transform(new FastLockNode(0, obj, box) )->as_FastLock();
3226 if (UseBiasedLocking && PrintPreciseBiasedLockingStatistics) {
3227 // Create the counters for this fast lock.
3228 flock->create_lock_counter(sync_jvms()); // sync_jvms used to get current bci
3229 }
3230
3231 // Create the rtm counters for this fast lock if needed.
3232 flock->create_rtm_lock_counter(sync_jvms()); // sync_jvms used to get current bci
3233
3234 // Add monitor to debug info for the slow path. If we block inside the
3235 // slow path and de-opt, we need the monitor hanging around
3236 map()->push_monitor( flock );
3237
3238 const TypeFunc *tf = LockNode::lock_type();
3239 LockNode *lock = new LockNode(C, tf);
3240
3241 lock->init_req( TypeFunc::Control, control() );
3242 lock->init_req( TypeFunc::Memory , mem );
3243 lock->init_req( TypeFunc::I_O , top() ) ; // does no i/o
3244 lock->init_req( TypeFunc::FramePtr, frameptr() );
3245 lock->init_req( TypeFunc::ReturnAdr, top() );
3246
3247 lock->init_req(TypeFunc::Parms + 0, obj);
3248 lock->init_req(TypeFunc::Parms + 1, box);
3249 lock->init_req(TypeFunc::Parms + 2, flock);
3250 add_safepoint_edges(lock);
3251
3252 lock = _gvn.transform( lock )->as_Lock();
3253
3254 // lock has no side-effects, sets few values
3255 set_predefined_output_for_runtime_call(lock, mem, TypeRawPtr::BOTTOM);
3256
3257 insert_mem_bar(Op_MemBarAcquireLock);
3258
3259 // Add this to the worklist so that the lock can be eliminated
3260 record_for_igvn(lock);
3261
3262 #ifndef PRODUCT
3263 if (PrintLockStatistics) {
3264 // Update the counter for this lock. Don't bother using an atomic
3265 // operation since we don't require absolute accuracy.
3266 lock->create_lock_counter(map()->jvms());
3267 increment_counter(lock->counter()->addr());
3268 }
3269 #endif
3270
3271 return flock;
3272 }
3273
3274
3275 //------------------------------shared_unlock----------------------------------
3276 // Emit unlocking code.
3277 void GraphKit::shared_unlock(Node* box, Node* obj) {
3278 // bci is either a monitorenter bc or InvocationEntryBci
3279 // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3280 assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3281
3282 if( !GenerateSynchronizationCode )
3283 return;
3284 if (stopped()) { // Dead monitor?
3285 map()->pop_monitor(); // Kill monitor from debug info
3286 return;
3287 }
3288
3289 // Memory barrier to avoid floating things down past the locked region
3290 insert_mem_bar(Op_MemBarReleaseLock);
3291
3292 const TypeFunc *tf = OptoRuntime::complete_monitor_exit_Type();
3293 UnlockNode *unlock = new UnlockNode(C, tf);
3294 #ifdef ASSERT
3295 unlock->set_dbg_jvms(sync_jvms());
3296 #endif
3297 uint raw_idx = Compile::AliasIdxRaw;
3298 unlock->init_req( TypeFunc::Control, control() );
3299 unlock->init_req( TypeFunc::Memory , memory(raw_idx) );
3300 unlock->init_req( TypeFunc::I_O , top() ) ; // does no i/o
3301 unlock->init_req( TypeFunc::FramePtr, frameptr() );
3302 unlock->init_req( TypeFunc::ReturnAdr, top() );
3303
3304 unlock->init_req(TypeFunc::Parms + 0, obj);
3305 unlock->init_req(TypeFunc::Parms + 1, box);
3306 unlock = _gvn.transform(unlock)->as_Unlock();
3307
3308 Node* mem = reset_memory();
3309
3310 // unlock has no side-effects, sets few values
3311 set_predefined_output_for_runtime_call(unlock, mem, TypeRawPtr::BOTTOM);
3312
3313 // Kill monitor from debug info
3314 map()->pop_monitor( );
3315 }
3316
3317 //-------------------------------get_layout_helper-----------------------------
3318 // If the given klass is a constant or known to be an array,
3319 // fetch the constant layout helper value into constant_value
3320 // and return (Node*)NULL. Otherwise, load the non-constant
3321 // layout helper value, and return the node which represents it.
3322 // This two-faced routine is useful because allocation sites
3323 // almost always feature constant types.
3324 Node* GraphKit::get_layout_helper(Node* klass_node, jint& constant_value) {
3325 const TypeKlassPtr* inst_klass = _gvn.type(klass_node)->isa_klassptr();
3326 if (!StressReflectiveCode && inst_klass != NULL) {
3327 ciKlass* klass = inst_klass->klass();
3328 bool xklass = inst_klass->klass_is_exact();
3329 if (xklass || klass->is_array_klass()) {
3330 jint lhelper = klass->layout_helper();
3331 if (lhelper != Klass::_lh_neutral_value) {
3332 constant_value = lhelper;
3333 return (Node*) NULL;
3334 }
3335 }
3336 }
3337 constant_value = Klass::_lh_neutral_value; // put in a known value
3338 Node* lhp = basic_plus_adr(klass_node, klass_node, in_bytes(Klass::layout_helper_offset()));
3339 return make_load(NULL, lhp, TypeInt::INT, T_INT, MemNode::unordered);
3340 }
3341
3342 // We just put in an allocate/initialize with a big raw-memory effect.
3343 // Hook selected additional alias categories on the initialization.
3344 static void hook_memory_on_init(GraphKit& kit, int alias_idx,
3345 MergeMemNode* init_in_merge,
3346 Node* init_out_raw) {
3347 DEBUG_ONLY(Node* init_in_raw = init_in_merge->base_memory());
3348 assert(init_in_merge->memory_at(alias_idx) == init_in_raw, "");
3349
3350 Node* prevmem = kit.memory(alias_idx);
3351 init_in_merge->set_memory_at(alias_idx, prevmem);
3352 kit.set_memory(init_out_raw, alias_idx);
3353 }
3354
3355 //---------------------------set_output_for_allocation-------------------------
3356 Node* GraphKit::set_output_for_allocation(AllocateNode* alloc,
3357 const TypeOopPtr* oop_type,
3358 bool deoptimize_on_exception) {
3359 int rawidx = Compile::AliasIdxRaw;
3360 alloc->set_req( TypeFunc::FramePtr, frameptr() );
3361 add_safepoint_edges(alloc);
3362 Node* allocx = _gvn.transform(alloc);
3363 set_control( _gvn.transform(new ProjNode(allocx, TypeFunc::Control) ) );
3364 // create memory projection for i_o
3365 set_memory ( _gvn.transform( new ProjNode(allocx, TypeFunc::Memory, true) ), rawidx );
3366 make_slow_call_ex(allocx, env()->Throwable_klass(), true, deoptimize_on_exception);
3367
3368 // create a memory projection as for the normal control path
3369 Node* malloc = _gvn.transform(new ProjNode(allocx, TypeFunc::Memory));
3370 set_memory(malloc, rawidx);
3371
3372 // a normal slow-call doesn't change i_o, but an allocation does
3373 // we create a separate i_o projection for the normal control path
3374 set_i_o(_gvn.transform( new ProjNode(allocx, TypeFunc::I_O, false) ) );
3375 Node* rawoop = _gvn.transform( new ProjNode(allocx, TypeFunc::Parms) );
3376
3377 // put in an initialization barrier
3378 InitializeNode* init = insert_mem_bar_volatile(Op_Initialize, rawidx,
3379 rawoop)->as_Initialize();
3380 assert(alloc->initialization() == init, "2-way macro link must work");
3381 assert(init ->allocation() == alloc, "2-way macro link must work");
3382 {
3383 // Extract memory strands which may participate in the new object's
3384 // initialization, and source them from the new InitializeNode.
3385 // This will allow us to observe initializations when they occur,
3386 // and link them properly (as a group) to the InitializeNode.
3387 assert(init->in(InitializeNode::Memory) == malloc, "");
3388 MergeMemNode* minit_in = MergeMemNode::make(malloc);
3389 init->set_req(InitializeNode::Memory, minit_in);
3390 record_for_igvn(minit_in); // fold it up later, if possible
3391 Node* minit_out = memory(rawidx);
3392 assert(minit_out->is_Proj() && minit_out->in(0) == init, "");
3393 if (oop_type->isa_aryptr()) {
3394 const TypePtr* telemref = oop_type->add_offset(Type::OffsetBot);
3395 int elemidx = C->get_alias_index(telemref);
3396 hook_memory_on_init(*this, elemidx, minit_in, minit_out);
3397 } else if (oop_type->isa_instptr()) {
3398 ciInstanceKlass* ik = oop_type->klass()->as_instance_klass();
3399 for (int i = 0, len = ik->nof_nonstatic_fields(); i < len; i++) {
3400 ciField* field = ik->nonstatic_field_at(i);
3401 if (field->offset() >= TrackedInitializationLimit * HeapWordSize)
3402 continue; // do not bother to track really large numbers of fields
3403 // Find (or create) the alias category for this field:
3404 int fieldidx = C->alias_type(field)->index();
3405 hook_memory_on_init(*this, fieldidx, minit_in, minit_out);
3406 }
3407 }
3408 }
3409
3410 // Cast raw oop to the real thing...
3411 Node* javaoop = new CheckCastPPNode(control(), rawoop, oop_type);
3412 javaoop = _gvn.transform(javaoop);
3413 C->set_recent_alloc(control(), javaoop);
3414 assert(just_allocated_object(control()) == javaoop, "just allocated");
3415
3416 #ifdef ASSERT
3417 { // Verify that the AllocateNode::Ideal_allocation recognizers work:
3418 assert(AllocateNode::Ideal_allocation(rawoop, &_gvn) == alloc,
3419 "Ideal_allocation works");
3420 assert(AllocateNode::Ideal_allocation(javaoop, &_gvn) == alloc,
3421 "Ideal_allocation works");
3422 if (alloc->is_AllocateArray()) {
3423 assert(AllocateArrayNode::Ideal_array_allocation(rawoop, &_gvn) == alloc->as_AllocateArray(),
3424 "Ideal_allocation works");
3425 assert(AllocateArrayNode::Ideal_array_allocation(javaoop, &_gvn) == alloc->as_AllocateArray(),
3426 "Ideal_allocation works");
3427 } else {
3428 assert(alloc->in(AllocateNode::ALength)->is_top(), "no length, please");
3429 }
3430 }
3431 #endif //ASSERT
3432
3433 return javaoop;
3434 }
3435
3436 //---------------------------new_instance--------------------------------------
3437 // This routine takes a klass_node which may be constant (for a static type)
3438 // or may be non-constant (for reflective code). It will work equally well
3439 // for either, and the graph will fold nicely if the optimizer later reduces
3440 // the type to a constant.
3441 // The optional arguments are for specialized use by intrinsics:
3442 // - If 'extra_slow_test' if not null is an extra condition for the slow-path.
3443 // - If 'return_size_val', report the the total object size to the caller.
3444 // - deoptimize_on_exception controls how Java exceptions are handled (rethrow vs deoptimize)
3445 Node* GraphKit::new_instance(Node* klass_node,
3446 Node* extra_slow_test,
3447 Node* *return_size_val,
3448 bool deoptimize_on_exception) {
3449 // Compute size in doublewords
3450 // The size is always an integral number of doublewords, represented
3451 // as a positive bytewise size stored in the klass's layout_helper.
3452 // The layout_helper also encodes (in a low bit) the need for a slow path.
3453 jint layout_con = Klass::_lh_neutral_value;
3454 Node* layout_val = get_layout_helper(klass_node, layout_con);
3455 int layout_is_con = (layout_val == NULL);
3456
3457 if (extra_slow_test == NULL) extra_slow_test = intcon(0);
3458 // Generate the initial go-slow test. It's either ALWAYS (return a
3459 // Node for 1) or NEVER (return a NULL) or perhaps (in the reflective
3460 // case) a computed value derived from the layout_helper.
3461 Node* initial_slow_test = NULL;
3462 if (layout_is_con) {
3463 assert(!StressReflectiveCode, "stress mode does not use these paths");
3464 bool must_go_slow = Klass::layout_helper_needs_slow_path(layout_con);
3465 initial_slow_test = must_go_slow ? intcon(1) : extra_slow_test;
3466 } else { // reflective case
3467 // This reflective path is used by Unsafe.allocateInstance.
3468 // (It may be stress-tested by specifying StressReflectiveCode.)
3469 // Basically, we want to get into the VM is there's an illegal argument.
3470 Node* bit = intcon(Klass::_lh_instance_slow_path_bit);
3471 initial_slow_test = _gvn.transform( new AndINode(layout_val, bit) );
3472 if (extra_slow_test != intcon(0)) {
3473 initial_slow_test = _gvn.transform( new OrINode(initial_slow_test, extra_slow_test) );
3474 }
3475 // (Macro-expander will further convert this to a Bool, if necessary.)
3476 }
3477
3478 // Find the size in bytes. This is easy; it's the layout_helper.
3479 // The size value must be valid even if the slow path is taken.
3480 Node* size = NULL;
3481 if (layout_is_con) {
3482 size = MakeConX(Klass::layout_helper_size_in_bytes(layout_con));
3483 } else { // reflective case
3484 // This reflective path is used by clone and Unsafe.allocateInstance.
3485 size = ConvI2X(layout_val);
3486
3487 // Clear the low bits to extract layout_helper_size_in_bytes:
3488 assert((int)Klass::_lh_instance_slow_path_bit < BytesPerLong, "clear bit");
3489 Node* mask = MakeConX(~ (intptr_t)right_n_bits(LogBytesPerLong));
3490 size = _gvn.transform( new AndXNode(size, mask) );
3491 }
3492 if (return_size_val != NULL) {
3493 (*return_size_val) = size;
3494 }
3495
3496 // This is a precise notnull oop of the klass.
3497 // (Actually, it need not be precise if this is a reflective allocation.)
3498 // It's what we cast the result to.
3499 const TypeKlassPtr* tklass = _gvn.type(klass_node)->isa_klassptr();
3500 if (!tklass) tklass = TypeKlassPtr::OBJECT;
3501 const TypeOopPtr* oop_type = tklass->as_instance_type();
3502
3503 // Now generate allocation code
3504
3505 // The entire memory state is needed for slow path of the allocation
3506 // since GC and deoptimization can happened.
3507 Node *mem = reset_memory();
3508 set_all_memory(mem); // Create new memory state
3509
3510 AllocateNode* alloc = new AllocateNode(C, AllocateNode::alloc_type(Type::TOP),
3511 control(), mem, i_o(),
3512 size, klass_node,
3513 initial_slow_test);
3514
3515 return set_output_for_allocation(alloc, oop_type, deoptimize_on_exception);
3516 }
3517
3518 //-------------------------------new_array-------------------------------------
3519 // helper for both newarray and anewarray
3520 // The 'length' parameter is (obviously) the length of the array.
3521 // See comments on new_instance for the meaning of the other arguments.
3522 Node* GraphKit::new_array(Node* klass_node, // array klass (maybe variable)
3523 Node* length, // number of array elements
3524 int nargs, // number of arguments to push back for uncommon trap
3525 Node* *return_size_val,
3526 bool deoptimize_on_exception) {
3527 jint layout_con = Klass::_lh_neutral_value;
3528 Node* layout_val = get_layout_helper(klass_node, layout_con);
3529 int layout_is_con = (layout_val == NULL);
3530
3531 if (!layout_is_con && !StressReflectiveCode &&
3532 !too_many_traps(Deoptimization::Reason_class_check)) {
3533 // This is a reflective array creation site.
3534 // Optimistically assume that it is a subtype of Object[],
3535 // so that we can fold up all the address arithmetic.
3536 layout_con = Klass::array_layout_helper(T_OBJECT);
3537 Node* cmp_lh = _gvn.transform( new CmpINode(layout_val, intcon(layout_con)) );
3538 Node* bol_lh = _gvn.transform( new BoolNode(cmp_lh, BoolTest::eq) );
3539 { BuildCutout unless(this, bol_lh, PROB_MAX);
3540 inc_sp(nargs);
3541 uncommon_trap(Deoptimization::Reason_class_check,
3542 Deoptimization::Action_maybe_recompile);
3543 }
3544 layout_val = NULL;
3545 layout_is_con = true;
3546 }
3547
3548 // Generate the initial go-slow test. Make sure we do not overflow
3549 // if length is huge (near 2Gig) or negative! We do not need
3550 // exact double-words here, just a close approximation of needed
3551 // double-words. We can't add any offset or rounding bits, lest we
3552 // take a size -1 of bytes and make it positive. Use an unsigned
3553 // compare, so negative sizes look hugely positive.
3554 int fast_size_limit = FastAllocateSizeLimit;
3555 if (layout_is_con) {
3556 assert(!StressReflectiveCode, "stress mode does not use these paths");
3557 // Increase the size limit if we have exact knowledge of array type.
3558 int log2_esize = Klass::layout_helper_log2_element_size(layout_con);
3559 fast_size_limit <<= (LogBytesPerLong - log2_esize);
3560 }
3561
3562 Node* initial_slow_cmp = _gvn.transform( new CmpUNode( length, intcon( fast_size_limit ) ) );
3563 Node* initial_slow_test = _gvn.transform( new BoolNode( initial_slow_cmp, BoolTest::gt ) );
3564
3565 // --- Size Computation ---
3566 // array_size = round_to_heap(array_header + (length << elem_shift));
3567 // where round_to_heap(x) == round_to(x, MinObjAlignmentInBytes)
3568 // and round_to(x, y) == ((x + y-1) & ~(y-1))
3569 // The rounding mask is strength-reduced, if possible.
3570 int round_mask = MinObjAlignmentInBytes - 1;
3571 Node* header_size = NULL;
3572 int header_size_min = arrayOopDesc::base_offset_in_bytes(T_BYTE);
3573 // (T_BYTE has the weakest alignment and size restrictions...)
3574 if (layout_is_con) {
3575 int hsize = Klass::layout_helper_header_size(layout_con);
3576 int eshift = Klass::layout_helper_log2_element_size(layout_con);
3577 BasicType etype = Klass::layout_helper_element_type(layout_con);
3578 if ((round_mask & ~right_n_bits(eshift)) == 0)
3579 round_mask = 0; // strength-reduce it if it goes away completely
3580 assert((hsize & right_n_bits(eshift)) == 0, "hsize is pre-rounded");
3581 assert(header_size_min <= hsize, "generic minimum is smallest");
3582 header_size_min = hsize;
3583 header_size = intcon(hsize + round_mask);
3584 } else {
3585 Node* hss = intcon(Klass::_lh_header_size_shift);
3586 Node* hsm = intcon(Klass::_lh_header_size_mask);
3587 Node* hsize = _gvn.transform( new URShiftINode(layout_val, hss) );
3588 hsize = _gvn.transform( new AndINode(hsize, hsm) );
3589 Node* mask = intcon(round_mask);
3590 header_size = _gvn.transform( new AddINode(hsize, mask) );
3591 }
3592
3593 Node* elem_shift = NULL;
3594 if (layout_is_con) {
3595 int eshift = Klass::layout_helper_log2_element_size(layout_con);
3596 if (eshift != 0)
3597 elem_shift = intcon(eshift);
3598 } else {
3599 // There is no need to mask or shift this value.
3600 // The semantics of LShiftINode include an implicit mask to 0x1F.
3601 assert(Klass::_lh_log2_element_size_shift == 0, "use shift in place");
3602 elem_shift = layout_val;
3603 }
3604
3605 // Transition to native address size for all offset calculations:
3606 Node* lengthx = ConvI2X(length);
3607 Node* headerx = ConvI2X(header_size);
3608 #ifdef _LP64
3609 { const TypeInt* tilen = _gvn.find_int_type(length);
3610 if (tilen != NULL && tilen->_lo < 0) {
3611 // Add a manual constraint to a positive range. Cf. array_element_address.
3612 jint size_max = fast_size_limit;
3613 if (size_max > tilen->_hi) size_max = tilen->_hi;
3614 const TypeInt* tlcon = TypeInt::make(0, size_max, Type::WidenMin);
3615
3616 // Only do a narrow I2L conversion if the range check passed.
3617 IfNode* iff = new IfNode(control(), initial_slow_test, PROB_MIN, COUNT_UNKNOWN);
3618 _gvn.transform(iff);
3619 RegionNode* region = new RegionNode(3);
3620 _gvn.set_type(region, Type::CONTROL);
3621 lengthx = new PhiNode(region, TypeLong::LONG);
3622 _gvn.set_type(lengthx, TypeLong::LONG);
3623
3624 // Range check passed. Use ConvI2L node with narrow type.
3625 Node* passed = IfFalse(iff);
3626 region->init_req(1, passed);
3627 // Make I2L conversion control dependent to prevent it from
3628 // floating above the range check during loop optimizations.
3629 lengthx->init_req(1, C->constrained_convI2L(&_gvn, length, tlcon, passed));
3630
3631 // Range check failed. Use ConvI2L with wide type because length may be invalid.
3632 region->init_req(2, IfTrue(iff));
3633 lengthx->init_req(2, ConvI2X(length));
3634
3635 set_control(region);
3636 record_for_igvn(region);
3637 record_for_igvn(lengthx);
3638 }
3639 }
3640 #endif
3641
3642 // Combine header size (plus rounding) and body size. Then round down.
3643 // This computation cannot overflow, because it is used only in two
3644 // places, one where the length is sharply limited, and the other
3645 // after a successful allocation.
3646 Node* abody = lengthx;
3647 if (elem_shift != NULL)
3648 abody = _gvn.transform( new LShiftXNode(lengthx, elem_shift) );
3649 Node* size = _gvn.transform( new AddXNode(headerx, abody) );
3650 if (round_mask != 0) {
3651 Node* mask = MakeConX(~round_mask);
3652 size = _gvn.transform( new AndXNode(size, mask) );
3653 }
3654 // else if round_mask == 0, the size computation is self-rounding
3655
3656 if (return_size_val != NULL) {
3657 // This is the size
3658 (*return_size_val) = size;
3659 }
3660
3661 // Now generate allocation code
3662
3663 // The entire memory state is needed for slow path of the allocation
3664 // since GC and deoptimization can happened.
3665 Node *mem = reset_memory();
3666 set_all_memory(mem); // Create new memory state
3667
3668 if (initial_slow_test->is_Bool()) {
3669 // Hide it behind a CMoveI, or else PhaseIdealLoop::split_up will get sick.
3670 initial_slow_test = initial_slow_test->as_Bool()->as_int_value(&_gvn);
3671 }
3672
3673 // Create the AllocateArrayNode and its result projections
3674 AllocateArrayNode* alloc
3675 = new AllocateArrayNode(C, AllocateArrayNode::alloc_type(TypeInt::INT),
3676 control(), mem, i_o(),
3677 size, klass_node,
3678 initial_slow_test,
3679 length);
3680
3681 // Cast to correct type. Note that the klass_node may be constant or not,
3682 // and in the latter case the actual array type will be inexact also.
3683 // (This happens via a non-constant argument to inline_native_newArray.)
3684 // In any case, the value of klass_node provides the desired array type.
3685 const TypeInt* length_type = _gvn.find_int_type(length);
3686 const TypeOopPtr* ary_type = _gvn.type(klass_node)->is_klassptr()->as_instance_type();
3687 if (ary_type->isa_aryptr() && length_type != NULL) {
3688 // Try to get a better type than POS for the size
3689 ary_type = ary_type->is_aryptr()->cast_to_size(length_type);
3690 }
3691
3692 Node* javaoop = set_output_for_allocation(alloc, ary_type, deoptimize_on_exception);
3693
3694 // Cast length on remaining path to be as narrow as possible
3695 if (map()->find_edge(length) >= 0) {
3696 Node* ccast = alloc->make_ideal_length(ary_type, &_gvn);
3697 if (ccast != length) {
3698 _gvn.set_type_bottom(ccast);
3699 record_for_igvn(ccast);
3700 replace_in_map(length, ccast);
3701 }
3702 }
3703
3704 return javaoop;
3705 }
3706
3707 // The following "Ideal_foo" functions are placed here because they recognize
3708 // the graph shapes created by the functions immediately above.
3709
3710 //---------------------------Ideal_allocation----------------------------------
3711 // Given an oop pointer or raw pointer, see if it feeds from an AllocateNode.
3712 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase) {
3713 if (ptr == NULL) { // reduce dumb test in callers
3714 return NULL;
3715 }
3716 if (ptr->is_CheckCastPP()) { // strip only one raw-to-oop cast
3717 ptr = ptr->in(1);
3718 if (ptr == NULL) return NULL;
3719 }
3720 // Return NULL for allocations with several casts:
3721 // j.l.reflect.Array.newInstance(jobject, jint)
3722 // Object.clone()
3723 // to keep more precise type from last cast.
3724 if (ptr->is_Proj()) {
3725 Node* allo = ptr->in(0);
3726 if (allo != NULL && allo->is_Allocate()) {
3727 return allo->as_Allocate();
3728 }
3729 }
3730 // Report failure to match.
3731 return NULL;
3732 }
3733
3734 // Fancy version which also strips off an offset (and reports it to caller).
3735 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase,
3736 intptr_t& offset) {
3737 Node* base = AddPNode::Ideal_base_and_offset(ptr, phase, offset);
3738 if (base == NULL) return NULL;
3739 return Ideal_allocation(base, phase);
3740 }
3741
3742 // Trace Initialize <- Proj[Parm] <- Allocate
3743 AllocateNode* InitializeNode::allocation() {
3744 Node* rawoop = in(InitializeNode::RawAddress);
3745 if (rawoop->is_Proj()) {
3746 Node* alloc = rawoop->in(0);
3747 if (alloc->is_Allocate()) {
3748 return alloc->as_Allocate();
3749 }
3750 }
3751 return NULL;
3752 }
3753
3754 // Trace Allocate -> Proj[Parm] -> Initialize
3755 InitializeNode* AllocateNode::initialization() {
3756 ProjNode* rawoop = proj_out(AllocateNode::RawAddress);
3757 if (rawoop == NULL) return NULL;
3758 for (DUIterator_Fast imax, i = rawoop->fast_outs(imax); i < imax; i++) {
3759 Node* init = rawoop->fast_out(i);
3760 if (init->is_Initialize()) {
3761 assert(init->as_Initialize()->allocation() == this, "2-way link");
3762 return init->as_Initialize();
3763 }
3764 }
3765 return NULL;
3766 }
3767
3768 //----------------------------- loop predicates ---------------------------
3769
3770 //------------------------------add_predicate_impl----------------------------
3771 void GraphKit::add_predicate_impl(Deoptimization::DeoptReason reason, int nargs) {
3772 // Too many traps seen?
3773 if (too_many_traps(reason)) {
3774 #ifdef ASSERT
3775 if (TraceLoopPredicate) {
3776 int tc = C->trap_count(reason);
3777 tty->print("too many traps=%s tcount=%d in ",
3778 Deoptimization::trap_reason_name(reason), tc);
3779 method()->print(); // which method has too many predicate traps
3780 tty->cr();
3781 }
3782 #endif
3783 // We cannot afford to take more traps here,
3784 // do not generate predicate.
3785 return;
3786 }
3787
3788 Node *cont = _gvn.intcon(1);
3789 Node* opq = _gvn.transform(new Opaque1Node(C, cont));
3790 Node *bol = _gvn.transform(new Conv2BNode(opq));
3791 IfNode* iff = create_and_map_if(control(), bol, PROB_MAX, COUNT_UNKNOWN);
3792 Node* iffalse = _gvn.transform(new IfFalseNode(iff));
3793 C->add_predicate_opaq(opq);
3794 {
3795 PreserveJVMState pjvms(this);
3796 set_control(iffalse);
3797 inc_sp(nargs);
3798 uncommon_trap(reason, Deoptimization::Action_maybe_recompile);
3799 }
3800 Node* iftrue = _gvn.transform(new IfTrueNode(iff));
3801 set_control(iftrue);
3802 }
3803
3804 //------------------------------add_predicate---------------------------------
3805 void GraphKit::add_predicate(int nargs) {
3806 if (UseLoopPredicate) {
3807 add_predicate_impl(Deoptimization::Reason_predicate, nargs);
3808 }
3809 // loop's limit check predicate should be near the loop.
3810 add_predicate_impl(Deoptimization::Reason_loop_limit_check, nargs);
3811 }
3812
3813 //----------------------------- store barriers ----------------------------
3814 #define __ ideal.
3815
3816 void GraphKit::sync_kit(IdealKit& ideal) {
3817 set_all_memory(__ merged_memory());
3818 set_i_o(__ i_o());
3819 set_control(__ ctrl());
3820 }
3821
3822 void GraphKit::final_sync(IdealKit& ideal) {
3823 // Final sync IdealKit and graphKit.
3824 sync_kit(ideal);
3825 }
3826
3827 Node* GraphKit::byte_map_base_node() {
3828 // Get base of card map
3829 CardTableModRefBS* ct =
3830 barrier_set_cast<CardTableModRefBS>(Universe::heap()->barrier_set());
3831 assert(sizeof(*ct->byte_map_base) == sizeof(jbyte), "adjust users of this code");
3832 if (ct->byte_map_base != NULL) {
3833 return makecon(TypeRawPtr::make((address)ct->byte_map_base));
3834 } else {
3835 return null();
3836 }
3837 }
3838
3839 // vanilla/CMS post barrier
3840 // Insert a write-barrier store. This is to let generational GC work; we have
3841 // to flag all oop-stores before the next GC point.
3842 void GraphKit::write_barrier_post(Node* oop_store,
3843 Node* obj,
3844 Node* adr,
3845 uint adr_idx,
3846 Node* val,
3847 bool use_precise) {
3848 // No store check needed if we're storing a NULL or an old object
3849 // (latter case is probably a string constant). The concurrent
3850 // mark sweep garbage collector, however, needs to have all nonNull
3851 // oop updates flagged via card-marks.
3852 if (val != NULL && val->is_Con()) {
3853 // must be either an oop or NULL
3854 const Type* t = val->bottom_type();
3855 if (t == TypePtr::NULL_PTR || t == Type::TOP)
3856 // stores of null never (?) need barriers
3857 return;
3858 }
3859
3860 if (use_ReduceInitialCardMarks()
3861 && obj == just_allocated_object(control())) {
3862 // We can skip marks on a freshly-allocated object in Eden.
3863 // Keep this code in sync with new_store_pre_barrier() in runtime.cpp.
3864 // That routine informs GC to take appropriate compensating steps,
3865 // upon a slow-path allocation, so as to make this card-mark
3866 // elision safe.
3867 return;
3868 }
3869
3870 if (!use_precise) {
3871 // All card marks for a (non-array) instance are in one place:
3872 adr = obj;
3873 }
3874 // (Else it's an array (or unknown), and we want more precise card marks.)
3875 assert(adr != NULL, "");
3876
3877 IdealKit ideal(this, true);
3878
3879 // Convert the pointer to an int prior to doing math on it
3880 Node* cast = __ CastPX(__ ctrl(), adr);
3881
3882 // Divide by card size
3883 assert(Universe::heap()->barrier_set()->is_a(BarrierSet::CardTableModRef),
3884 "Only one we handle so far.");
3885 Node* card_offset = __ URShiftX( cast, __ ConI(CardTableModRefBS::card_shift) );
3886
3887 // Combine card table base and card offset
3888 Node* card_adr = __ AddP(__ top(), byte_map_base_node(), card_offset );
3889
3890 // Get the alias_index for raw card-mark memory
3891 int adr_type = Compile::AliasIdxRaw;
3892 Node* zero = __ ConI(0); // Dirty card value
3893 BasicType bt = T_BYTE;
3894
3895 if (UseConcMarkSweepGC && UseCondCardMark) {
3896 insert_mem_bar(Op_MemBarVolatile); // StoreLoad barrier
3897 __ sync_kit(this);
3898 }
3899
3900 if (UseCondCardMark) {
3901 // The classic GC reference write barrier is typically implemented
3902 // as a store into the global card mark table. Unfortunately
3903 // unconditional stores can result in false sharing and excessive
3904 // coherence traffic as well as false transactional aborts.
3905 // UseCondCardMark enables MP "polite" conditional card mark
3906 // stores. In theory we could relax the load from ctrl() to
3907 // no_ctrl, but that doesn't buy much latitude.
3908 Node* card_val = __ load( __ ctrl(), card_adr, TypeInt::BYTE, bt, adr_type);
3909 __ if_then(card_val, BoolTest::ne, zero);
3910 }
3911
3912 // Smash zero into card
3913 if( !UseConcMarkSweepGC ) {
3914 __ store(__ ctrl(), card_adr, zero, bt, adr_type, MemNode::unordered);
3915 } else {
3916 // Specialized path for CM store barrier
3917 __ storeCM(__ ctrl(), card_adr, zero, oop_store, adr_idx, bt, adr_type);
3918 }
3919
3920 if (UseCondCardMark) {
3921 __ end_if();
3922 }
3923
3924 // Final sync IdealKit and GraphKit.
3925 final_sync(ideal);
3926 }
3927 /*
3928 * Determine if the G1 pre-barrier can be removed. The pre-barrier is
3929 * required by SATB to make sure all objects live at the start of the
3930 * marking are kept alive, all reference updates need to any previous
3931 * reference stored before writing.
3932 *
3933 * If the previous value is NULL there is no need to save the old value.
3934 * References that are NULL are filtered during runtime by the barrier
3935 * code to avoid unnecessary queuing.
3936 *
3937 * However in the case of newly allocated objects it might be possible to
3938 * prove that the reference about to be overwritten is NULL during compile
3939 * time and avoid adding the barrier code completely.
3940 *
3941 * The compiler needs to determine that the object in which a field is about
3942 * to be written is newly allocated, and that no prior store to the same field
3943 * has happened since the allocation.
3944 *
3945 * Returns true if the pre-barrier can be removed
3946 */
3947 bool GraphKit::g1_can_remove_pre_barrier(PhaseTransform* phase, Node* adr,
3948 BasicType bt, uint adr_idx) {
3949 intptr_t offset = 0;
3950 Node* base = AddPNode::Ideal_base_and_offset(adr, phase, offset);
3951 AllocateNode* alloc = AllocateNode::Ideal_allocation(base, phase);
3952
3953 if (offset == Type::OffsetBot) {
3954 return false; // cannot unalias unless there are precise offsets
3955 }
3956
3957 if (alloc == NULL) {
3958 return false; // No allocation found
3959 }
3960
3961 intptr_t size_in_bytes = type2aelembytes(bt);
3962
3963 Node* mem = memory(adr_idx); // start searching here...
3964
3965 for (int cnt = 0; cnt < 50; cnt++) {
3966
3967 if (mem->is_Store()) {
3968
3969 Node* st_adr = mem->in(MemNode::Address);
3970 intptr_t st_offset = 0;
3971 Node* st_base = AddPNode::Ideal_base_and_offset(st_adr, phase, st_offset);
3972
3973 if (st_base == NULL) {
3974 break; // inscrutable pointer
3975 }
3976
3977 // Break we have found a store with same base and offset as ours so break
3978 if (st_base == base && st_offset == offset) {
3979 break;
3980 }
3981
3982 if (st_offset != offset && st_offset != Type::OffsetBot) {
3983 const int MAX_STORE = BytesPerLong;
3984 if (st_offset >= offset + size_in_bytes ||
3985 st_offset <= offset - MAX_STORE ||
3986 st_offset <= offset - mem->as_Store()->memory_size()) {
3987 // Success: The offsets are provably independent.
3988 // (You may ask, why not just test st_offset != offset and be done?
3989 // The answer is that stores of different sizes can co-exist
3990 // in the same sequence of RawMem effects. We sometimes initialize
3991 // a whole 'tile' of array elements with a single jint or jlong.)
3992 mem = mem->in(MemNode::Memory);
3993 continue; // advance through independent store memory
3994 }
3995 }
3996
3997 if (st_base != base
3998 && MemNode::detect_ptr_independence(base, alloc, st_base,
3999 AllocateNode::Ideal_allocation(st_base, phase),
4000 phase)) {
4001 // Success: The bases are provably independent.
4002 mem = mem->in(MemNode::Memory);
4003 continue; // advance through independent store memory
4004 }
4005 } else if (mem->is_Proj() && mem->in(0)->is_Initialize()) {
4006
4007 InitializeNode* st_init = mem->in(0)->as_Initialize();
4008 AllocateNode* st_alloc = st_init->allocation();
4009
4010 // Make sure that we are looking at the same allocation site.
4011 // The alloc variable is guaranteed to not be null here from earlier check.
4012 if (alloc == st_alloc) {
4013 // Check that the initialization is storing NULL so that no previous store
4014 // has been moved up and directly write a reference
4015 Node* captured_store = st_init->find_captured_store(offset,
4016 type2aelembytes(T_OBJECT),
4017 phase);
4018 if (captured_store == NULL || captured_store == st_init->zero_memory()) {
4019 return true;
4020 }
4021 }
4022 }
4023
4024 // Unless there is an explicit 'continue', we must bail out here,
4025 // because 'mem' is an inscrutable memory state (e.g., a call).
4026 break;
4027 }
4028
4029 return false;
4030 }
4031
4032 // G1 pre/post barriers
4033 void GraphKit::g1_write_barrier_pre(bool do_load,
4034 Node* obj,
4035 Node* adr,
4036 uint alias_idx,
4037 Node* val,
4038 const TypeOopPtr* val_type,
4039 Node* pre_val,
4040 BasicType bt) {
4041
4042 // Some sanity checks
4043 // Note: val is unused in this routine.
4044
4045 if (do_load) {
4046 // We need to generate the load of the previous value
4047 assert(obj != NULL, "must have a base");
4048 assert(adr != NULL, "where are loading from?");
4049 assert(pre_val == NULL, "loaded already?");
4050 assert(val_type != NULL, "need a type");
4051
4052 if (use_ReduceInitialCardMarks()
4053 && g1_can_remove_pre_barrier(&_gvn, adr, bt, alias_idx)) {
4054 return;
4055 }
4056
4057 } else {
4058 // In this case both val_type and alias_idx are unused.
4059 assert(pre_val != NULL, "must be loaded already");
4060 // Nothing to be done if pre_val is null.
4061 if (pre_val->bottom_type() == TypePtr::NULL_PTR) return;
4062 assert(pre_val->bottom_type()->basic_type() == T_OBJECT, "or we shouldn't be here");
4063 }
4064 assert(bt == T_OBJECT, "or we shouldn't be here");
4065
4066 IdealKit ideal(this, true);
4067
4068 Node* tls = __ thread(); // ThreadLocalStorage
4069
4070 Node* no_ctrl = NULL;
4071 Node* no_base = __ top();
4072 Node* zero = __ ConI(0);
4073 Node* zeroX = __ ConX(0);
4074
4075 float likely = PROB_LIKELY(0.999);
4076 float unlikely = PROB_UNLIKELY(0.999);
4077
4078 BasicType active_type = in_bytes(SATBMarkQueue::byte_width_of_active()) == 4 ? T_INT : T_BYTE;
4079 assert(in_bytes(SATBMarkQueue::byte_width_of_active()) == 4 || in_bytes(SATBMarkQueue::byte_width_of_active()) == 1, "flag width");
4080
4081 // Offsets into the thread
4082 const int marking_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 648
4083 SATBMarkQueue::byte_offset_of_active());
4084 const int index_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 656
4085 SATBMarkQueue::byte_offset_of_index());
4086 const int buffer_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 652
4087 SATBMarkQueue::byte_offset_of_buf());
4088
4089 // Now the actual pointers into the thread
4090 Node* marking_adr = __ AddP(no_base, tls, __ ConX(marking_offset));
4091 Node* buffer_adr = __ AddP(no_base, tls, __ ConX(buffer_offset));
4092 Node* index_adr = __ AddP(no_base, tls, __ ConX(index_offset));
4093
4094 // Now some of the values
4095 Node* marking = __ load(__ ctrl(), marking_adr, TypeInt::INT, active_type, Compile::AliasIdxRaw);
4096
4097 // if (!marking)
4098 __ if_then(marking, BoolTest::ne, zero, unlikely); {
4099 BasicType index_bt = TypeX_X->basic_type();
4100 assert(sizeof(size_t) == type2aelembytes(index_bt), "Loading G1 SATBMarkQueue::_index with wrong size.");
4101 Node* index = __ load(__ ctrl(), index_adr, TypeX_X, index_bt, Compile::AliasIdxRaw);
4102
4103 if (do_load) {
4104 // load original value
4105 // alias_idx correct??
4106 pre_val = __ load(__ ctrl(), adr, val_type, bt, alias_idx);
4107 }
4108
4109 // if (pre_val != NULL)
4110 __ if_then(pre_val, BoolTest::ne, null()); {
4111 Node* buffer = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw);
4112
4113 // is the queue for this thread full?
4114 __ if_then(index, BoolTest::ne, zeroX, likely); {
4115
4116 // decrement the index
4117 Node* next_index = _gvn.transform(new SubXNode(index, __ ConX(sizeof(intptr_t))));
4118
4119 // Now get the buffer location we will log the previous value into and store it
4120 Node *log_addr = __ AddP(no_base, buffer, next_index);
4121 __ store(__ ctrl(), log_addr, pre_val, T_OBJECT, Compile::AliasIdxRaw, MemNode::unordered);
4122 // update the index
4123 __ store(__ ctrl(), index_adr, next_index, index_bt, Compile::AliasIdxRaw, MemNode::unordered);
4124
4125 } __ else_(); {
4126
4127 // logging buffer is full, call the runtime
4128 const TypeFunc *tf = OptoRuntime::g1_wb_pre_Type();
4129 __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_pre), "g1_wb_pre", pre_val, tls);
4130 } __ end_if(); // (!index)
4131 } __ end_if(); // (pre_val != NULL)
4132 } __ end_if(); // (!marking)
4133
4134 // Final sync IdealKit and GraphKit.
4135 final_sync(ideal);
4136 }
4137
4138 /*
4139 * G1 similar to any GC with a Young Generation requires a way to keep track of
4140 * references from Old Generation to Young Generation to make sure all live
4141 * objects are found. G1 also requires to keep track of object references
4142 * between different regions to enable evacuation of old regions, which is done
4143 * as part of mixed collections. References are tracked in remembered sets and
4144 * is continuously updated as reference are written to with the help of the
4145 * post-barrier.
4146 *
4147 * To reduce the number of updates to the remembered set the post-barrier
4148 * filters updates to fields in objects located in the Young Generation,
4149 * the same region as the reference, when the NULL is being written or
4150 * if the card is already marked as dirty by an earlier write.
4151 *
4152 * Under certain circumstances it is possible to avoid generating the
4153 * post-barrier completely if it is possible during compile time to prove
4154 * the object is newly allocated and that no safepoint exists between the
4155 * allocation and the store.
4156 *
4157 * In the case of slow allocation the allocation code must handle the barrier
4158 * as part of the allocation in the case the allocated object is not located
4159 * in the nursery, this would happen for humongous objects. This is similar to
4160 * how CMS is required to handle this case, see the comments for the method
4161 * CollectedHeap::new_store_pre_barrier and OptoRuntime::new_store_pre_barrier.
4162 * A deferred card mark is required for these objects and handled in the above
4163 * mentioned methods.
4164 *
4165 * Returns true if the post barrier can be removed
4166 */
4167 bool GraphKit::g1_can_remove_post_barrier(PhaseTransform* phase, Node* store,
4168 Node* adr) {
4169 intptr_t offset = 0;
4170 Node* base = AddPNode::Ideal_base_and_offset(adr, phase, offset);
4171 AllocateNode* alloc = AllocateNode::Ideal_allocation(base, phase);
4172
4173 if (offset == Type::OffsetBot) {
4174 return false; // cannot unalias unless there are precise offsets
4175 }
4176
4177 if (alloc == NULL) {
4178 return false; // No allocation found
4179 }
4180
4181 // Start search from Store node
4182 Node* mem = store->in(MemNode::Control);
4183 if (mem->is_Proj() && mem->in(0)->is_Initialize()) {
4184
4185 InitializeNode* st_init = mem->in(0)->as_Initialize();
4186 AllocateNode* st_alloc = st_init->allocation();
4187
4188 // Make sure we are looking at the same allocation
4189 if (alloc == st_alloc) {
4190 return true;
4191 }
4192 }
4193
4194 return false;
4195 }
4196
4197 //
4198 // Update the card table and add card address to the queue
4199 //
4200 void GraphKit::g1_mark_card(IdealKit& ideal,
4201 Node* card_adr,
4202 Node* oop_store,
4203 uint oop_alias_idx,
4204 Node* index,
4205 Node* index_adr,
4206 Node* buffer,
4207 const TypeFunc* tf) {
4208
4209 Node* zero = __ ConI(0);
4210 Node* zeroX = __ ConX(0);
4211 Node* no_base = __ top();
4212 BasicType card_bt = T_BYTE;
4213 // Smash zero into card. MUST BE ORDERED WRT TO STORE
4214 __ storeCM(__ ctrl(), card_adr, zero, oop_store, oop_alias_idx, card_bt, Compile::AliasIdxRaw);
4215
4216 // Now do the queue work
4217 __ if_then(index, BoolTest::ne, zeroX); {
4218
4219 Node* next_index = _gvn.transform(new SubXNode(index, __ ConX(sizeof(intptr_t))));
4220 Node* log_addr = __ AddP(no_base, buffer, next_index);
4221
4222 // Order, see storeCM.
4223 __ store(__ ctrl(), log_addr, card_adr, T_ADDRESS, Compile::AliasIdxRaw, MemNode::unordered);
4224 __ store(__ ctrl(), index_adr, next_index, TypeX_X->basic_type(), Compile::AliasIdxRaw, MemNode::unordered);
4225
4226 } __ else_(); {
4227 __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_post), "g1_wb_post", card_adr, __ thread());
4228 } __ end_if();
4229
4230 }
4231
4232 void GraphKit::g1_write_barrier_post(Node* oop_store,
4233 Node* obj,
4234 Node* adr,
4235 uint alias_idx,
4236 Node* val,
4237 BasicType bt,
4238 bool use_precise) {
4239 // If we are writing a NULL then we need no post barrier
4240
4241 if (val != NULL && val->is_Con() && val->bottom_type() == TypePtr::NULL_PTR) {
4242 // Must be NULL
4243 const Type* t = val->bottom_type();
4244 assert(t == Type::TOP || t == TypePtr::NULL_PTR, "must be NULL");
4245 // No post barrier if writing NULLx
4246 return;
4247 }
4248
4249 if (use_ReduceInitialCardMarks() && obj == just_allocated_object(control())) {
4250 // We can skip marks on a freshly-allocated object in Eden.
4251 // Keep this code in sync with new_store_pre_barrier() in runtime.cpp.
4252 // That routine informs GC to take appropriate compensating steps,
4253 // upon a slow-path allocation, so as to make this card-mark
4254 // elision safe.
4255 return;
4256 }
4257
4258 if (use_ReduceInitialCardMarks()
4259 && g1_can_remove_post_barrier(&_gvn, oop_store, adr)) {
4260 return;
4261 }
4262
4263 if (!use_precise) {
4264 // All card marks for a (non-array) instance are in one place:
4265 adr = obj;
4266 }
4267 // (Else it's an array (or unknown), and we want more precise card marks.)
4268 assert(adr != NULL, "");
4269
4270 IdealKit ideal(this, true);
4271
4272 Node* tls = __ thread(); // ThreadLocalStorage
4273
4274 Node* no_base = __ top();
4275 float likely = PROB_LIKELY(0.999);
4276 float unlikely = PROB_UNLIKELY(0.999);
4277 Node* young_card = __ ConI((jint)G1SATBCardTableModRefBS::g1_young_card_val());
4278 Node* dirty_card = __ ConI((jint)CardTableModRefBS::dirty_card_val());
4279 Node* zeroX = __ ConX(0);
4280
4281 // Get the alias_index for raw card-mark memory
4282 const TypePtr* card_type = TypeRawPtr::BOTTOM;
4283
4284 const TypeFunc *tf = OptoRuntime::g1_wb_post_Type();
4285
4286 // Offsets into the thread
4287 const int index_offset = in_bytes(JavaThread::dirty_card_queue_offset() +
4288 DirtyCardQueue::byte_offset_of_index());
4289 const int buffer_offset = in_bytes(JavaThread::dirty_card_queue_offset() +
4290 DirtyCardQueue::byte_offset_of_buf());
4291
4292 // Pointers into the thread
4293
4294 Node* buffer_adr = __ AddP(no_base, tls, __ ConX(buffer_offset));
4295 Node* index_adr = __ AddP(no_base, tls, __ ConX(index_offset));
4296
4297 // Now some values
4298 // Use ctrl to avoid hoisting these values past a safepoint, which could
4299 // potentially reset these fields in the JavaThread.
4300 Node* index = __ load(__ ctrl(), index_adr, TypeX_X, TypeX_X->basic_type(), Compile::AliasIdxRaw);
4301 Node* buffer = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw);
4302
4303 // Convert the store obj pointer to an int prior to doing math on it
4304 // Must use ctrl to prevent "integerized oop" existing across safepoint
4305 Node* cast = __ CastPX(__ ctrl(), adr);
4306
4307 // Divide pointer by card size
4308 Node* card_offset = __ URShiftX( cast, __ ConI(CardTableModRefBS::card_shift) );
4309
4310 // Combine card table base and card offset
4311 Node* card_adr = __ AddP(no_base, byte_map_base_node(), card_offset );
4312
4313 // If we know the value being stored does it cross regions?
4314
4315 if (val != NULL) {
4316 // Does the store cause us to cross regions?
4317
4318 // Should be able to do an unsigned compare of region_size instead of
4319 // and extra shift. Do we have an unsigned compare??
4320 // Node* region_size = __ ConI(1 << HeapRegion::LogOfHRGrainBytes);
4321 Node* xor_res = __ URShiftX ( __ XorX( cast, __ CastPX(__ ctrl(), val)), __ ConI(HeapRegion::LogOfHRGrainBytes));
4322
4323 // if (xor_res == 0) same region so skip
4324 __ if_then(xor_res, BoolTest::ne, zeroX); {
4325
4326 // No barrier if we are storing a NULL
4327 __ if_then(val, BoolTest::ne, null(), unlikely); {
4328
4329 // Ok must mark the card if not already dirty
4330
4331 // load the original value of the card
4332 Node* card_val = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw);
4333
4334 __ if_then(card_val, BoolTest::ne, young_card); {
4335 sync_kit(ideal);
4336 // Use Op_MemBarVolatile to achieve the effect of a StoreLoad barrier.
4337 insert_mem_bar(Op_MemBarVolatile, oop_store);
4338 __ sync_kit(this);
4339
4340 Node* card_val_reload = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw);
4341 __ if_then(card_val_reload, BoolTest::ne, dirty_card); {
4342 g1_mark_card(ideal, card_adr, oop_store, alias_idx, index, index_adr, buffer, tf);
4343 } __ end_if();
4344 } __ end_if();
4345 } __ end_if();
4346 } __ end_if();
4347 } else {
4348 // The Object.clone() intrinsic uses this path if !ReduceInitialCardMarks.
4349 // We don't need a barrier here if the destination is a newly allocated object
4350 // in Eden. Otherwise, GC verification breaks because we assume that cards in Eden
4351 // are set to 'g1_young_gen' (see G1SATBCardTableModRefBS::verify_g1_young_region()).
4352 assert(!use_ReduceInitialCardMarks(), "can only happen with card marking");
4353 Node* card_val = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw);
4354 __ if_then(card_val, BoolTest::ne, young_card); {
4355 g1_mark_card(ideal, card_adr, oop_store, alias_idx, index, index_adr, buffer, tf);
4356 } __ end_if();
4357 }
4358
4359 // Final sync IdealKit and GraphKit.
4360 final_sync(ideal);
4361 }
4362 #undef __
4363
4364
4365 Node* GraphKit::load_String_length(Node* ctrl, Node* str) {
4366 Node* len = load_array_length(load_String_value(ctrl, str));
4367 Node* coder = load_String_coder(ctrl, str);
4368 // Divide length by 2 if coder is UTF16
4369 return _gvn.transform(new RShiftINode(len, coder));
4370 }
4371
4372 Node* GraphKit::load_String_value(Node* ctrl, Node* str) {
4373 int value_offset = java_lang_String::value_offset_in_bytes();
4374 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4375 false, NULL, 0);
4376 const TypePtr* value_field_type = string_type->add_offset(value_offset);
4377 const TypeAryPtr* value_type = TypeAryPtr::make(TypePtr::NotNull,
4378 TypeAry::make(TypeInt::BYTE, TypeInt::POS),
4379 ciTypeArrayKlass::make(T_BYTE), true, 0);
4380 int value_field_idx = C->get_alias_index(value_field_type);
4381 Node* load = make_load(ctrl, basic_plus_adr(str, str, value_offset),
4382 value_type, T_OBJECT, value_field_idx, MemNode::unordered);
4383 // String.value field is known to be @Stable.
4384 if (UseImplicitStableValues) {
4385 load = cast_array_to_stable(load, value_type);
4386 }
4387 return load;
4388 }
4389
4390 Node* GraphKit::load_String_coder(Node* ctrl, Node* str) {
4391 if (!CompactStrings) {
4392 return intcon(java_lang_String::CODER_UTF16);
4393 }
4394 int coder_offset = java_lang_String::coder_offset_in_bytes();
4395 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4396 false, NULL, 0);
4397 const TypePtr* coder_field_type = string_type->add_offset(coder_offset);
4398 int coder_field_idx = C->get_alias_index(coder_field_type);
4399 return make_load(ctrl, basic_plus_adr(str, str, coder_offset),
4400 TypeInt::BYTE, T_BYTE, coder_field_idx, MemNode::unordered);
4401 }
4402
4403 void GraphKit::store_String_value(Node* ctrl, Node* str, Node* value) {
4404 int value_offset = java_lang_String::value_offset_in_bytes();
4405 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4406 false, NULL, 0);
4407 const TypePtr* value_field_type = string_type->add_offset(value_offset);
4408 store_oop_to_object(ctrl, str, basic_plus_adr(str, value_offset), value_field_type,
4409 value, TypeAryPtr::BYTES, T_OBJECT, MemNode::unordered);
4410 }
4411
4412 void GraphKit::store_String_coder(Node* ctrl, Node* str, Node* value) {
4413 int coder_offset = java_lang_String::coder_offset_in_bytes();
4414 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4415 false, NULL, 0);
4416 const TypePtr* coder_field_type = string_type->add_offset(coder_offset);
4417 int coder_field_idx = C->get_alias_index(coder_field_type);
4418 store_to_memory(ctrl, basic_plus_adr(str, coder_offset),
4419 value, T_BYTE, coder_field_idx, MemNode::unordered);
4420 }
4421
4422 // Capture src and dst memory state with a MergeMemNode
4423 Node* GraphKit::capture_memory(const TypePtr* src_type, const TypePtr* dst_type) {
4424 if (src_type == dst_type) {
4425 // Types are equal, we don't need a MergeMemNode
4426 return memory(src_type);
4427 }
4428 MergeMemNode* merge = MergeMemNode::make(map()->memory());
4429 record_for_igvn(merge); // fold it up later, if possible
4430 int src_idx = C->get_alias_index(src_type);
4431 int dst_idx = C->get_alias_index(dst_type);
4432 merge->set_memory_at(src_idx, memory(src_idx));
4433 merge->set_memory_at(dst_idx, memory(dst_idx));
4434 return merge;
4435 }
4436
4437 Node* GraphKit::compress_string(Node* src, const TypeAryPtr* src_type, Node* dst, Node* count) {
4438 assert(Matcher::match_rule_supported(Op_StrCompressedCopy), "Intrinsic not supported");
4439 assert(src_type == TypeAryPtr::BYTES || src_type == TypeAryPtr::CHARS, "invalid source type");
4440 // If input and output memory types differ, capture both states to preserve
4441 // the dependency between preceding and subsequent loads/stores.
4442 // For example, the following program:
4443 // StoreB
4444 // compress_string
4445 // LoadB
4446 // has this memory graph (use->def):
4447 // LoadB -> compress_string -> CharMem
4448 // ... -> StoreB -> ByteMem
4449 // The intrinsic hides the dependency between LoadB and StoreB, causing
4450 // the load to read from memory not containing the result of the StoreB.
4451 // The correct memory graph should look like this:
4452 // LoadB -> compress_string -> MergeMem(CharMem, StoreB(ByteMem))
4453 Node* mem = capture_memory(src_type, TypeAryPtr::BYTES);
4454 StrCompressedCopyNode* str = new StrCompressedCopyNode(control(), mem, src, dst, count);
4455 Node* res_mem = _gvn.transform(new SCMemProjNode(str));
4456 set_memory(res_mem, TypeAryPtr::BYTES);
4457 return str;
4458 }
4459
4460 void GraphKit::inflate_string(Node* src, Node* dst, const TypeAryPtr* dst_type, Node* count) {
4461 assert(Matcher::match_rule_supported(Op_StrInflatedCopy), "Intrinsic not supported");
4462 assert(dst_type == TypeAryPtr::BYTES || dst_type == TypeAryPtr::CHARS, "invalid dest type");
4463 // Capture src and dst memory (see comment in 'compress_string').
4464 Node* mem = capture_memory(TypeAryPtr::BYTES, dst_type);
4465 StrInflatedCopyNode* str = new StrInflatedCopyNode(control(), mem, src, dst, count);
4466 set_memory(_gvn.transform(str), dst_type);
4467 }
4468
4469 void GraphKit::inflate_string_slow(Node* src, Node* dst, Node* start, Node* count) {
4470 /**
4471 * int i_char = start;
4472 * for (int i_byte = 0; i_byte < count; i_byte++) {
4473 * dst[i_char++] = (char)(src[i_byte] & 0xff);
4474 * }
4475 */
4476 add_predicate();
4477 RegionNode* head = new RegionNode(3);
4478 head->init_req(1, control());
4479 gvn().set_type(head, Type::CONTROL);
4480 record_for_igvn(head);
4481
4482 Node* i_byte = new PhiNode(head, TypeInt::INT);
4483 i_byte->init_req(1, intcon(0));
4484 gvn().set_type(i_byte, TypeInt::INT);
4485 record_for_igvn(i_byte);
4486
4487 Node* i_char = new PhiNode(head, TypeInt::INT);
4488 i_char->init_req(1, start);
4489 gvn().set_type(i_char, TypeInt::INT);
4490 record_for_igvn(i_char);
4491
4492 Node* mem = PhiNode::make(head, memory(TypeAryPtr::BYTES), Type::MEMORY, TypeAryPtr::BYTES);
4493 gvn().set_type(mem, Type::MEMORY);
4494 record_for_igvn(mem);
4495 set_control(head);
4496 set_memory(mem, TypeAryPtr::BYTES);
4497 Node* ch = load_array_element(control(), src, i_byte, TypeAryPtr::BYTES);
4498 Node* st = store_to_memory(control(), array_element_address(dst, i_char, T_BYTE),
4499 AndI(ch, intcon(0xff)), T_CHAR, TypeAryPtr::BYTES, MemNode::unordered,
4500 false, false, true /* mismatched */);
4501
4502 IfNode* iff = create_and_map_if(head, Bool(CmpI(i_byte, count), BoolTest::lt), PROB_FAIR, COUNT_UNKNOWN);
4503 head->init_req(2, IfTrue(iff));
4504 mem->init_req(2, st);
4505 i_byte->init_req(2, AddI(i_byte, intcon(1)));
4506 i_char->init_req(2, AddI(i_char, intcon(2)));
4507
4508 set_control(IfFalse(iff));
4509 set_memory(st, TypeAryPtr::BYTES);
4510 }
4511
4512 Node* GraphKit::make_constant_from_field(ciField* field, Node* obj) {
4513 if (!field->is_constant()) {
4514 return NULL; // Field not marked as constant.
4515 }
4516 ciInstance* holder = NULL;
4517 if (!field->is_static()) {
4518 ciObject* const_oop = obj->bottom_type()->is_oopptr()->const_oop();
4519 if (const_oop != NULL && const_oop->is_instance()) {
4520 holder = const_oop->as_instance();
4521 }
4522 }
4523 const Type* con_type = Type::make_constant_from_field(field, holder, field->layout_type(),
4524 /*is_unsigned_load=*/false);
4525 if (con_type != NULL) {
4526 return makecon(con_type);
4527 }
4528 return NULL;
4529 }
4530
4531 Node* GraphKit::cast_array_to_stable(Node* ary, const TypeAryPtr* ary_type) {
4532 // Reify the property as a CastPP node in Ideal graph to comply with monotonicity
4533 // assumption of CCP analysis.
4534 return _gvn.transform(new CastPPNode(ary, ary_type->cast_to_stable(true)));
4535 }