1 /*
2 * Copyright (c) 2001, 2012, 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_implementation/g1/g1SATBCardTableModRefBS.hpp"
28 #include "gc_implementation/g1/heapRegion.hpp"
29 #include "gc_interface/collectedHeap.hpp"
30 #include "memory/barrierSet.hpp"
31 #include "memory/cardTableModRefBS.hpp"
32 #include "opto/addnode.hpp"
33 #include "opto/graphKit.hpp"
34 #include "opto/idealKit.hpp"
35 #include "opto/locknode.hpp"
36 #include "opto/machnode.hpp"
37 #include "opto/parse.hpp"
38 #include "opto/rootnode.hpp"
39 #include "opto/runtime.hpp"
40 #include "runtime/deoptimization.hpp"
41 #include "runtime/sharedRuntime.hpp"
42
43 //----------------------------GraphKit-----------------------------------------
44 // Main utility constructor.
45 GraphKit::GraphKit(JVMState* jvms)
46 : Phase(Phase::Parser),
47 _env(C->env()),
48 _gvn(*C->initial_gvn())
49 {
50 _exceptions = jvms->map()->next_exception();
51 if (_exceptions != NULL) jvms->map()->set_next_exception(NULL);
52 set_jvms(jvms);
53 }
54
55 // Private constructor for parser.
56 GraphKit::GraphKit()
57 : Phase(Phase::Parser),
58 _env(C->env()),
59 _gvn(*C->initial_gvn())
60 {
61 _exceptions = NULL;
62 set_map(NULL);
63 debug_only(_sp = -99);
64 debug_only(set_bci(-99));
65 }
66
67
68
69 //---------------------------clean_stack---------------------------------------
70 // Clear away rubbish from the stack area of the JVM state.
71 // This destroys any arguments that may be waiting on the stack.
72 void GraphKit::clean_stack(int from_sp) {
73 SafePointNode* map = this->map();
74 JVMState* jvms = this->jvms();
75 int stk_size = jvms->stk_size();
76 int stkoff = jvms->stkoff();
77 Node* top = this->top();
78 for (int i = from_sp; i < stk_size; i++) {
79 if (map->in(stkoff + i) != top) {
80 map->set_req(stkoff + i, top);
81 }
82 }
83 }
84
85
86 //--------------------------------sync_jvms-----------------------------------
87 // Make sure our current jvms agrees with our parse state.
88 JVMState* GraphKit::sync_jvms() const {
89 JVMState* jvms = this->jvms();
90 jvms->set_bci(bci()); // Record the new bci in the JVMState
91 jvms->set_sp(sp()); // Record the new sp in the JVMState
92 assert(jvms_in_sync(), "jvms is now in sync");
93 return jvms;
94 }
95
96 //--------------------------------sync_jvms_for_reexecute---------------------
97 // Make sure our current jvms agrees with our parse state. This version
98 // uses the reexecute_sp for reexecuting bytecodes.
99 JVMState* GraphKit::sync_jvms_for_reexecute() {
100 JVMState* jvms = this->jvms();
101 jvms->set_bci(bci()); // Record the new bci in the JVMState
102 jvms->set_sp(reexecute_sp()); // Record the new sp in the JVMState
103 return jvms;
104 }
105
106 #ifdef ASSERT
107 bool GraphKit::jvms_in_sync() const {
108 Parse* parse = is_Parse();
109 if (parse == NULL) {
110 if (bci() != jvms()->bci()) return false;
111 if (sp() != (int)jvms()->sp()) return false;
112 return true;
113 }
114 if (jvms()->method() != parse->method()) return false;
115 if (jvms()->bci() != parse->bci()) return false;
116 int jvms_sp = jvms()->sp();
117 if (jvms_sp != parse->sp()) return false;
118 int jvms_depth = jvms()->depth();
119 if (jvms_depth != parse->depth()) return false;
120 return true;
121 }
122
123 // Local helper checks for special internal merge points
124 // used to accumulate and merge exception states.
125 // They are marked by the region's in(0) edge being the map itself.
126 // Such merge points must never "escape" into the parser at large,
127 // until they have been handed to gvn.transform.
128 static bool is_hidden_merge(Node* reg) {
129 if (reg == NULL) return false;
130 if (reg->is_Phi()) {
131 reg = reg->in(0);
132 if (reg == NULL) return false;
133 }
134 return reg->is_Region() && reg->in(0) != NULL && reg->in(0)->is_Root();
135 }
136
137 void GraphKit::verify_map() const {
138 if (map() == NULL) return; // null map is OK
139 assert(map()->req() <= jvms()->endoff(), "no extra garbage on map");
140 assert(!map()->has_exceptions(), "call add_exception_states_from 1st");
141 assert(!is_hidden_merge(control()), "call use_exception_state, not set_map");
142 }
143
144 void GraphKit::verify_exception_state(SafePointNode* ex_map) {
145 assert(ex_map->next_exception() == NULL, "not already part of a chain");
146 assert(has_saved_ex_oop(ex_map), "every exception state has an ex_oop");
147 }
148 #endif
149
150 //---------------------------stop_and_kill_map---------------------------------
151 // Set _map to NULL, signalling a stop to further bytecode execution.
152 // First smash the current map's control to a constant, to mark it dead.
153 void GraphKit::stop_and_kill_map() {
154 SafePointNode* dead_map = stop();
155 if (dead_map != NULL) {
156 dead_map->disconnect_inputs(NULL, C); // Mark the map as killed.
157 assert(dead_map->is_killed(), "must be so marked");
158 }
159 }
160
161
162 //--------------------------------stopped--------------------------------------
163 // Tell if _map is NULL, or control is top.
164 bool GraphKit::stopped() {
165 if (map() == NULL) return true;
166 else if (control() == top()) return true;
167 else return false;
168 }
169
170
171 //-----------------------------has_ex_handler----------------------------------
172 // Tell if this method or any caller method has exception handlers.
173 bool GraphKit::has_ex_handler() {
174 for (JVMState* jvmsp = jvms(); jvmsp != NULL; jvmsp = jvmsp->caller()) {
175 if (jvmsp->has_method() && jvmsp->method()->has_exception_handlers()) {
176 return true;
177 }
178 }
179 return false;
180 }
181
182 //------------------------------save_ex_oop------------------------------------
183 // Save an exception without blowing stack contents or other JVM state.
184 void GraphKit::set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop) {
185 assert(!has_saved_ex_oop(ex_map), "clear ex-oop before setting again");
186 ex_map->add_req(ex_oop);
187 debug_only(verify_exception_state(ex_map));
188 }
189
190 inline static Node* common_saved_ex_oop(SafePointNode* ex_map, bool clear_it) {
191 assert(GraphKit::has_saved_ex_oop(ex_map), "ex_oop must be there");
192 Node* ex_oop = ex_map->in(ex_map->req()-1);
193 if (clear_it) ex_map->del_req(ex_map->req()-1);
194 return ex_oop;
195 }
196
197 //-----------------------------saved_ex_oop------------------------------------
198 // Recover a saved exception from its map.
199 Node* GraphKit::saved_ex_oop(SafePointNode* ex_map) {
200 return common_saved_ex_oop(ex_map, false);
201 }
202
203 //--------------------------clear_saved_ex_oop---------------------------------
204 // Erase a previously saved exception from its map.
205 Node* GraphKit::clear_saved_ex_oop(SafePointNode* ex_map) {
206 return common_saved_ex_oop(ex_map, true);
207 }
208
209 #ifdef ASSERT
210 //---------------------------has_saved_ex_oop----------------------------------
211 // Erase a previously saved exception from its map.
212 bool GraphKit::has_saved_ex_oop(SafePointNode* ex_map) {
213 return ex_map->req() == ex_map->jvms()->endoff()+1;
214 }
215 #endif
216
217 //-------------------------make_exception_state--------------------------------
218 // Turn the current JVM state into an exception state, appending the ex_oop.
219 SafePointNode* GraphKit::make_exception_state(Node* ex_oop) {
220 sync_jvms();
221 SafePointNode* ex_map = stop(); // do not manipulate this map any more
222 set_saved_ex_oop(ex_map, ex_oop);
223 return ex_map;
224 }
225
226
227 //--------------------------add_exception_state--------------------------------
228 // Add an exception to my list of exceptions.
229 void GraphKit::add_exception_state(SafePointNode* ex_map) {
230 if (ex_map == NULL || ex_map->control() == top()) {
231 return;
232 }
233 #ifdef ASSERT
234 verify_exception_state(ex_map);
235 if (has_exceptions()) {
236 assert(ex_map->jvms()->same_calls_as(_exceptions->jvms()), "all collected exceptions must come from the same place");
237 }
238 #endif
239
240 // If there is already an exception of exactly this type, merge with it.
241 // In particular, null-checks and other low-level exceptions common up here.
242 Node* ex_oop = saved_ex_oop(ex_map);
243 const Type* ex_type = _gvn.type(ex_oop);
244 if (ex_oop == top()) {
245 // No action needed.
246 return;
247 }
248 assert(ex_type->isa_instptr(), "exception must be an instance");
249 for (SafePointNode* e2 = _exceptions; e2 != NULL; e2 = e2->next_exception()) {
250 const Type* ex_type2 = _gvn.type(saved_ex_oop(e2));
251 // We check sp also because call bytecodes can generate exceptions
252 // both before and after arguments are popped!
253 if (ex_type2 == ex_type
254 && e2->_jvms->sp() == ex_map->_jvms->sp()) {
255 combine_exception_states(ex_map, e2);
256 return;
257 }
258 }
259
260 // No pre-existing exception of the same type. Chain it on the list.
261 push_exception_state(ex_map);
262 }
263
264 //-----------------------add_exception_states_from-----------------------------
265 void GraphKit::add_exception_states_from(JVMState* jvms) {
266 SafePointNode* ex_map = jvms->map()->next_exception();
267 if (ex_map != NULL) {
268 jvms->map()->set_next_exception(NULL);
269 for (SafePointNode* next_map; ex_map != NULL; ex_map = next_map) {
270 next_map = ex_map->next_exception();
271 ex_map->set_next_exception(NULL);
272 add_exception_state(ex_map);
273 }
274 }
275 }
276
277 //-----------------------transfer_exceptions_into_jvms-------------------------
278 JVMState* GraphKit::transfer_exceptions_into_jvms() {
279 if (map() == NULL) {
280 // We need a JVMS to carry the exceptions, but the map has gone away.
281 // Create a scratch JVMS, cloned from any of the exception states...
282 if (has_exceptions()) {
283 _map = _exceptions;
284 _map = clone_map();
285 _map->set_next_exception(NULL);
286 clear_saved_ex_oop(_map);
287 debug_only(verify_map());
288 } else {
289 // ...or created from scratch
290 JVMState* jvms = new (C) JVMState(_method, NULL);
291 jvms->set_bci(_bci);
292 jvms->set_sp(_sp);
293 jvms->set_map(new (C) SafePointNode(TypeFunc::Parms, jvms));
294 set_jvms(jvms);
295 for (uint i = 0; i < map()->req(); i++) map()->init_req(i, top());
296 set_all_memory(top());
297 while (map()->req() < jvms->endoff()) map()->add_req(top());
298 }
299 // (This is a kludge, in case you didn't notice.)
300 set_control(top());
301 }
302 JVMState* jvms = sync_jvms();
303 assert(!jvms->map()->has_exceptions(), "no exceptions on this map yet");
304 jvms->map()->set_next_exception(_exceptions);
305 _exceptions = NULL; // done with this set of exceptions
306 return jvms;
307 }
308
309 static inline void add_n_reqs(Node* dstphi, Node* srcphi) {
310 assert(is_hidden_merge(dstphi), "must be a special merge node");
311 assert(is_hidden_merge(srcphi), "must be a special merge node");
312 uint limit = srcphi->req();
313 for (uint i = PhiNode::Input; i < limit; i++) {
314 dstphi->add_req(srcphi->in(i));
315 }
316 }
317 static inline void add_one_req(Node* dstphi, Node* src) {
318 assert(is_hidden_merge(dstphi), "must be a special merge node");
319 assert(!is_hidden_merge(src), "must not be a special merge node");
320 dstphi->add_req(src);
321 }
322
323 //-----------------------combine_exception_states------------------------------
324 // This helper function combines exception states by building phis on a
325 // specially marked state-merging region. These regions and phis are
326 // untransformed, and can build up gradually. The region is marked by
327 // having a control input of its exception map, rather than NULL. Such
328 // regions do not appear except in this function, and in use_exception_state.
329 void GraphKit::combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map) {
330 if (failing()) return; // dying anyway...
331 JVMState* ex_jvms = ex_map->_jvms;
332 assert(ex_jvms->same_calls_as(phi_map->_jvms), "consistent call chains");
333 assert(ex_jvms->stkoff() == phi_map->_jvms->stkoff(), "matching locals");
334 assert(ex_jvms->sp() == phi_map->_jvms->sp(), "matching stack sizes");
335 assert(ex_jvms->monoff() == phi_map->_jvms->monoff(), "matching JVMS");
336 assert(ex_map->req() == phi_map->req(), "matching maps");
337 uint tos = ex_jvms->stkoff() + ex_jvms->sp();
338 Node* hidden_merge_mark = root();
339 Node* region = phi_map->control();
340 MergeMemNode* phi_mem = phi_map->merged_memory();
341 MergeMemNode* ex_mem = ex_map->merged_memory();
342 if (region->in(0) != hidden_merge_mark) {
343 // The control input is not (yet) a specially-marked region in phi_map.
344 // Make it so, and build some phis.
345 region = new (C) RegionNode(2);
346 _gvn.set_type(region, Type::CONTROL);
347 region->set_req(0, hidden_merge_mark); // marks an internal ex-state
348 region->init_req(1, phi_map->control());
349 phi_map->set_control(region);
350 Node* io_phi = PhiNode::make(region, phi_map->i_o(), Type::ABIO);
351 record_for_igvn(io_phi);
352 _gvn.set_type(io_phi, Type::ABIO);
353 phi_map->set_i_o(io_phi);
354 for (MergeMemStream mms(phi_mem); mms.next_non_empty(); ) {
355 Node* m = mms.memory();
356 Node* m_phi = PhiNode::make(region, m, Type::MEMORY, mms.adr_type(C));
357 record_for_igvn(m_phi);
358 _gvn.set_type(m_phi, Type::MEMORY);
359 mms.set_memory(m_phi);
360 }
361 }
362
363 // Either or both of phi_map and ex_map might already be converted into phis.
364 Node* ex_control = ex_map->control();
365 // if there is special marking on ex_map also, we add multiple edges from src
366 bool add_multiple = (ex_control->in(0) == hidden_merge_mark);
367 // how wide was the destination phi_map, originally?
368 uint orig_width = region->req();
369
370 if (add_multiple) {
371 add_n_reqs(region, ex_control);
372 add_n_reqs(phi_map->i_o(), ex_map->i_o());
373 } else {
374 // ex_map has no merges, so we just add single edges everywhere
375 add_one_req(region, ex_control);
376 add_one_req(phi_map->i_o(), ex_map->i_o());
377 }
378 for (MergeMemStream mms(phi_mem, ex_mem); mms.next_non_empty2(); ) {
379 if (mms.is_empty()) {
380 // get a copy of the base memory, and patch some inputs into it
381 const TypePtr* adr_type = mms.adr_type(C);
382 Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
383 assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
384 mms.set_memory(phi);
385 // Prepare to append interesting stuff onto the newly sliced phi:
386 while (phi->req() > orig_width) phi->del_req(phi->req()-1);
387 }
388 // Append stuff from ex_map:
389 if (add_multiple) {
390 add_n_reqs(mms.memory(), mms.memory2());
391 } else {
392 add_one_req(mms.memory(), mms.memory2());
393 }
394 }
395 uint limit = ex_map->req();
396 for (uint i = TypeFunc::Parms; i < limit; i++) {
397 // Skip everything in the JVMS after tos. (The ex_oop follows.)
398 if (i == tos) i = ex_jvms->monoff();
399 Node* src = ex_map->in(i);
400 Node* dst = phi_map->in(i);
401 if (src != dst) {
402 PhiNode* phi;
403 if (dst->in(0) != region) {
404 dst = phi = PhiNode::make(region, dst, _gvn.type(dst));
405 record_for_igvn(phi);
406 _gvn.set_type(phi, phi->type());
407 phi_map->set_req(i, dst);
408 // Prepare to append interesting stuff onto the new phi:
409 while (dst->req() > orig_width) dst->del_req(dst->req()-1);
410 } else {
411 assert(dst->is_Phi(), "nobody else uses a hidden region");
412 phi = (PhiNode*)dst;
413 }
414 if (add_multiple && src->in(0) == ex_control) {
415 // Both are phis.
416 add_n_reqs(dst, src);
417 } else {
418 while (dst->req() < region->req()) add_one_req(dst, src);
419 }
420 const Type* srctype = _gvn.type(src);
421 if (phi->type() != srctype) {
422 const Type* dsttype = phi->type()->meet(srctype);
423 if (phi->type() != dsttype) {
424 phi->set_type(dsttype);
425 _gvn.set_type(phi, dsttype);
426 }
427 }
428 }
429 }
430 phi_map->merge_replaced_nodes_with(ex_map);
431 }
432
433 //--------------------------use_exception_state--------------------------------
434 Node* GraphKit::use_exception_state(SafePointNode* phi_map) {
435 if (failing()) { stop(); return top(); }
436 Node* region = phi_map->control();
437 Node* hidden_merge_mark = root();
438 assert(phi_map->jvms()->map() == phi_map, "sanity: 1-1 relation");
439 Node* ex_oop = clear_saved_ex_oop(phi_map);
440 if (region->in(0) == hidden_merge_mark) {
441 // Special marking for internal ex-states. Process the phis now.
442 region->set_req(0, region); // now it's an ordinary region
443 set_jvms(phi_map->jvms()); // ...so now we can use it as a map
444 // Note: Setting the jvms also sets the bci and sp.
445 set_control(_gvn.transform(region));
446 uint tos = jvms()->stkoff() + sp();
447 for (uint i = 1; i < tos; i++) {
448 Node* x = phi_map->in(i);
449 if (x->in(0) == region) {
450 assert(x->is_Phi(), "expected a special phi");
451 phi_map->set_req(i, _gvn.transform(x));
452 }
453 }
454 for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
455 Node* x = mms.memory();
456 if (x->in(0) == region) {
457 assert(x->is_Phi(), "nobody else uses a hidden region");
458 mms.set_memory(_gvn.transform(x));
459 }
460 }
461 if (ex_oop->in(0) == region) {
462 assert(ex_oop->is_Phi(), "expected a special phi");
463 ex_oop = _gvn.transform(ex_oop);
464 }
465 } else {
466 set_jvms(phi_map->jvms());
467 }
468
469 assert(!is_hidden_merge(phi_map->control()), "hidden ex. states cleared");
470 assert(!is_hidden_merge(phi_map->i_o()), "hidden ex. states cleared");
471 return ex_oop;
472 }
473
474 //---------------------------------java_bc-------------------------------------
475 Bytecodes::Code GraphKit::java_bc() const {
476 ciMethod* method = this->method();
477 int bci = this->bci();
478 if (method != NULL && bci != InvocationEntryBci)
479 return method->java_code_at_bci(bci);
480 else
481 return Bytecodes::_illegal;
482 }
483
484 void GraphKit::uncommon_trap_if_should_post_on_exceptions(Deoptimization::DeoptReason reason,
485 bool must_throw) {
486 // if the exception capability is set, then we will generate code
487 // to check the JavaThread.should_post_on_exceptions flag to see
488 // if we actually need to report exception events (for this
489 // thread). If we don't need to report exception events, we will
490 // take the normal fast path provided by add_exception_events. If
491 // exception event reporting is enabled for this thread, we will
492 // take the uncommon_trap in the BuildCutout below.
493
494 // first must access the should_post_on_exceptions_flag in this thread's JavaThread
495 Node* jthread = _gvn.transform(new (C) ThreadLocalNode());
496 Node* adr = basic_plus_adr(top(), jthread, in_bytes(JavaThread::should_post_on_exceptions_flag_offset()));
497 Node* should_post_flag = make_load(control(), adr, TypeInt::INT, T_INT, Compile::AliasIdxRaw, false);
498
499 // Test the should_post_on_exceptions_flag vs. 0
500 Node* chk = _gvn.transform( new (C) CmpINode(should_post_flag, intcon(0)) );
501 Node* tst = _gvn.transform( new (C) BoolNode(chk, BoolTest::eq) );
502
503 // Branch to slow_path if should_post_on_exceptions_flag was true
504 { BuildCutout unless(this, tst, PROB_MAX);
505 // Do not try anything fancy if we're notifying the VM on every throw.
506 // Cf. case Bytecodes::_athrow in parse2.cpp.
507 uncommon_trap(reason, Deoptimization::Action_none,
508 (ciKlass*)NULL, (char*)NULL, must_throw);
509 }
510
511 }
512
513 //------------------------------builtin_throw----------------------------------
514 void GraphKit::builtin_throw(Deoptimization::DeoptReason reason, Node* arg) {
515 bool must_throw = true;
516
517 if (env()->jvmti_can_post_on_exceptions()) {
518 // check if we must post exception events, take uncommon trap if so
519 uncommon_trap_if_should_post_on_exceptions(reason, must_throw);
520 // here if should_post_on_exceptions is false
521 // continue on with the normal codegen
522 }
523
524 // If this particular condition has not yet happened at this
525 // bytecode, then use the uncommon trap mechanism, and allow for
526 // a future recompilation if several traps occur here.
527 // If the throw is hot, try to use a more complicated inline mechanism
528 // which keeps execution inside the compiled code.
529 bool treat_throw_as_hot = false;
530 ciMethodData* md = method()->method_data();
531
532 if (ProfileTraps) {
533 if (too_many_traps(reason)) {
534 treat_throw_as_hot = true;
535 }
536 // (If there is no MDO at all, assume it is early in
537 // execution, and that any deopts are part of the
538 // startup transient, and don't need to be remembered.)
539
540 // Also, if there is a local exception handler, treat all throws
541 // as hot if there has been at least one in this method.
542 if (C->trap_count(reason) != 0
543 && method()->method_data()->trap_count(reason) != 0
544 && has_ex_handler()) {
545 treat_throw_as_hot = true;
546 }
547 }
548
549 // If this throw happens frequently, an uncommon trap might cause
550 // a performance pothole. If there is a local exception handler,
551 // and if this particular bytecode appears to be deoptimizing often,
552 // let us handle the throw inline, with a preconstructed instance.
553 // Note: If the deopt count has blown up, the uncommon trap
554 // runtime is going to flush this nmethod, not matter what.
555 if (treat_throw_as_hot
556 && (!StackTraceInThrowable || OmitStackTraceInFastThrow)) {
557 // If the throw is local, we use a pre-existing instance and
558 // punt on the backtrace. This would lead to a missing backtrace
559 // (a repeat of 4292742) if the backtrace object is ever asked
560 // for its backtrace.
561 // Fixing this remaining case of 4292742 requires some flavor of
562 // escape analysis. Leave that for the future.
563 ciInstance* ex_obj = NULL;
564 switch (reason) {
565 case Deoptimization::Reason_null_check:
566 ex_obj = env()->NullPointerException_instance();
567 break;
568 case Deoptimization::Reason_div0_check:
569 ex_obj = env()->ArithmeticException_instance();
570 break;
571 case Deoptimization::Reason_range_check:
572 ex_obj = env()->ArrayIndexOutOfBoundsException_instance();
573 break;
574 case Deoptimization::Reason_class_check:
575 if (java_bc() == Bytecodes::_aastore) {
576 ex_obj = env()->ArrayStoreException_instance();
577 } else {
578 ex_obj = env()->ClassCastException_instance();
579 }
580 break;
581 }
582 if (failing()) { stop(); return; } // exception allocation might fail
583 if (ex_obj != NULL) {
584 // Cheat with a preallocated exception object.
585 if (C->log() != NULL)
586 C->log()->elem("hot_throw preallocated='1' reason='%s'",
587 Deoptimization::trap_reason_name(reason));
588 const TypeInstPtr* ex_con = TypeInstPtr::make(ex_obj);
589 Node* ex_node = _gvn.transform( ConNode::make(C, ex_con) );
590
591 // Clear the detail message of the preallocated exception object.
592 // Weblogic sometimes mutates the detail message of exceptions
593 // using reflection.
594 int offset = java_lang_Throwable::get_detailMessage_offset();
595 const TypePtr* adr_typ = ex_con->add_offset(offset);
596
597 Node *adr = basic_plus_adr(ex_node, ex_node, offset);
598 const TypeOopPtr* val_type = TypeOopPtr::make_from_klass(env()->String_klass());
599 // Conservatively release stores of object references.
600 Node *store = store_oop_to_object(control(), ex_node, adr, adr_typ, null(), val_type, T_OBJECT, StoreNode::release);
601
602 add_exception_state(make_exception_state(ex_node));
603 return;
604 }
605 }
606
607 // %%% Maybe add entry to OptoRuntime which directly throws the exc.?
608 // It won't be much cheaper than bailing to the interp., since we'll
609 // have to pass up all the debug-info, and the runtime will have to
610 // create the stack trace.
611
612 // Usual case: Bail to interpreter.
613 // Reserve the right to recompile if we haven't seen anything yet.
614
615 Deoptimization::DeoptAction action = Deoptimization::Action_maybe_recompile;
616 if (treat_throw_as_hot
617 && (method()->method_data()->trap_recompiled_at(bci())
618 || C->too_many_traps(reason))) {
619 // We cannot afford to take more traps here. Suffer in the interpreter.
620 if (C->log() != NULL)
621 C->log()->elem("hot_throw preallocated='0' reason='%s' mcount='%d'",
622 Deoptimization::trap_reason_name(reason),
623 C->trap_count(reason));
624 action = Deoptimization::Action_none;
625 }
626
627 // "must_throw" prunes the JVM state to include only the stack, if there
628 // are no local exception handlers. This should cut down on register
629 // allocation time and code size, by drastically reducing the number
630 // of in-edges on the call to the uncommon trap.
631
632 uncommon_trap(reason, action, (ciKlass*)NULL, (char*)NULL, must_throw);
633 }
634
635
636 //----------------------------PreserveJVMState---------------------------------
637 PreserveJVMState::PreserveJVMState(GraphKit* kit, bool clone_map) {
638 debug_only(kit->verify_map());
639 _kit = kit;
640 _map = kit->map(); // preserve the map
641 _sp = kit->sp();
642 kit->set_map(clone_map ? kit->clone_map() : NULL);
643 #ifdef ASSERT
644 _bci = kit->bci();
645 Parse* parser = kit->is_Parse();
646 int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo();
647 _block = block;
648 #endif
649 }
650 PreserveJVMState::~PreserveJVMState() {
651 GraphKit* kit = _kit;
652 #ifdef ASSERT
653 assert(kit->bci() == _bci, "bci must not shift");
654 Parse* parser = kit->is_Parse();
655 int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo();
656 assert(block == _block, "block must not shift");
657 #endif
658 kit->set_map(_map);
659 kit->set_sp(_sp);
660 }
661
662
663 //-----------------------------BuildCutout-------------------------------------
664 BuildCutout::BuildCutout(GraphKit* kit, Node* p, float prob, float cnt)
665 : PreserveJVMState(kit)
666 {
667 assert(p->is_Con() || p->is_Bool(), "test must be a bool");
668 SafePointNode* outer_map = _map; // preserved map is caller's
669 SafePointNode* inner_map = kit->map();
670 IfNode* iff = kit->create_and_map_if(outer_map->control(), p, prob, cnt);
671 outer_map->set_control(kit->gvn().transform( new (kit->C) IfTrueNode(iff) ));
672 inner_map->set_control(kit->gvn().transform( new (kit->C) IfFalseNode(iff) ));
673 }
674 BuildCutout::~BuildCutout() {
675 GraphKit* kit = _kit;
676 assert(kit->stopped(), "cutout code must stop, throw, return, etc.");
677 }
678
679 //---------------------------PreserveReexecuteState----------------------------
680 PreserveReexecuteState::PreserveReexecuteState(GraphKit* kit) {
681 assert(!kit->stopped(), "must call stopped() before");
682 _kit = kit;
683 _sp = kit->sp();
684 _reexecute = kit->jvms()->_reexecute;
685 }
686 PreserveReexecuteState::~PreserveReexecuteState() {
687 if (_kit->stopped()) return;
688 _kit->jvms()->_reexecute = _reexecute;
689 _kit->set_sp(_sp);
690 }
691
692 //------------------------------clone_map--------------------------------------
693 // Implementation of PreserveJVMState
694 //
695 // Only clone_map(...) here. If this function is only used in the
696 // PreserveJVMState class we may want to get rid of this extra
697 // function eventually and do it all there.
698
699 SafePointNode* GraphKit::clone_map() {
700 if (map() == NULL) return NULL;
701
702 // Clone the memory edge first
703 Node* mem = MergeMemNode::make(C, map()->memory());
704 gvn().set_type_bottom(mem);
705
706 SafePointNode *clonemap = (SafePointNode*)map()->clone();
707 JVMState* jvms = this->jvms();
708 JVMState* clonejvms = jvms->clone_shallow(C);
709 clonemap->set_memory(mem);
710 clonemap->set_jvms(clonejvms);
711 clonejvms->set_map(clonemap);
712 record_for_igvn(clonemap);
713 gvn().set_type_bottom(clonemap);
714 return clonemap;
715 }
716
717
718 //-----------------------------set_map_clone-----------------------------------
719 void GraphKit::set_map_clone(SafePointNode* m) {
720 _map = m;
721 _map = clone_map();
722 _map->set_next_exception(NULL);
723 debug_only(verify_map());
724 }
725
726
727 //----------------------------kill_dead_locals---------------------------------
728 // Detect any locals which are known to be dead, and force them to top.
729 void GraphKit::kill_dead_locals() {
730 // Consult the liveness information for the locals. If any
731 // of them are unused, then they can be replaced by top(). This
732 // should help register allocation time and cut down on the size
733 // of the deoptimization information.
734
735 // This call is made from many of the bytecode handling
736 // subroutines called from the Big Switch in do_one_bytecode.
737 // Every bytecode which might include a slow path is responsible
738 // for killing its dead locals. The more consistent we
739 // are about killing deads, the fewer useless phis will be
740 // constructed for them at various merge points.
741
742 // bci can be -1 (InvocationEntryBci). We return the entry
743 // liveness for the method.
744
745 if (method() == NULL || method()->code_size() == 0) {
746 // We are building a graph for a call to a native method.
747 // All locals are live.
748 return;
749 }
750
751 ResourceMark rm;
752
753 // Consult the liveness information for the locals. If any
754 // of them are unused, then they can be replaced by top(). This
755 // should help register allocation time and cut down on the size
756 // of the deoptimization information.
757 MethodLivenessResult live_locals = method()->liveness_at_bci(bci());
758
759 int len = (int)live_locals.size();
760 assert(len <= jvms()->loc_size(), "too many live locals");
761 for (int local = 0; local < len; local++) {
762 if (!live_locals.at(local)) {
763 set_local(local, top());
764 }
765 }
766 }
767
768 #ifdef ASSERT
769 //-------------------------dead_locals_are_killed------------------------------
770 // Return true if all dead locals are set to top in the map.
771 // Used to assert "clean" debug info at various points.
772 bool GraphKit::dead_locals_are_killed() {
773 if (method() == NULL || method()->code_size() == 0) {
774 // No locals need to be dead, so all is as it should be.
775 return true;
776 }
777
778 // Make sure somebody called kill_dead_locals upstream.
779 ResourceMark rm;
780 for (JVMState* jvms = this->jvms(); jvms != NULL; jvms = jvms->caller()) {
781 if (jvms->loc_size() == 0) continue; // no locals to consult
782 SafePointNode* map = jvms->map();
783 ciMethod* method = jvms->method();
784 int bci = jvms->bci();
785 if (jvms == this->jvms()) {
786 bci = this->bci(); // it might not yet be synched
787 }
788 MethodLivenessResult live_locals = method->liveness_at_bci(bci);
789 int len = (int)live_locals.size();
790 if (!live_locals.is_valid() || len == 0)
791 // This method is trivial, or is poisoned by a breakpoint.
792 return true;
793 assert(len == jvms->loc_size(), "live map consistent with locals map");
794 for (int local = 0; local < len; local++) {
795 if (!live_locals.at(local) && map->local(jvms, local) != top()) {
796 if (PrintMiscellaneous && (Verbose || WizardMode)) {
797 tty->print_cr("Zombie local %d: ", local);
798 jvms->dump();
799 }
800 return false;
801 }
802 }
803 }
804 return true;
805 }
806
807 #endif //ASSERT
808
809 // Helper function for enforcing certain bytecodes to reexecute if
810 // deoptimization happens
811 static bool should_reexecute_implied_by_bytecode(JVMState *jvms, bool is_anewarray) {
812 ciMethod* cur_method = jvms->method();
813 int cur_bci = jvms->bci();
814 if (cur_method != NULL && cur_bci != InvocationEntryBci) {
815 Bytecodes::Code code = cur_method->java_code_at_bci(cur_bci);
816 return Interpreter::bytecode_should_reexecute(code) ||
817 is_anewarray && code == Bytecodes::_multianewarray;
818 // Reexecute _multianewarray bytecode which was replaced with
819 // sequence of [a]newarray. See Parse::do_multianewarray().
820 //
821 // Note: interpreter should not have it set since this optimization
822 // is limited by dimensions and guarded by flag so in some cases
823 // multianewarray() runtime calls will be generated and
824 // the bytecode should not be reexecutes (stack will not be reset).
825 } else
826 return false;
827 }
828
829 // Helper function for adding JVMState and debug information to node
830 void GraphKit::add_safepoint_edges(SafePointNode* call, bool must_throw) {
831 // Add the safepoint edges to the call (or other safepoint).
832
833 // Make sure dead locals are set to top. This
834 // should help register allocation time and cut down on the size
835 // of the deoptimization information.
836 assert(dead_locals_are_killed(), "garbage in debug info before safepoint");
837
838 // Walk the inline list to fill in the correct set of JVMState's
839 // Also fill in the associated edges for each JVMState.
840
841 // If the bytecode needs to be reexecuted we need to put
842 // the arguments back on the stack.
843 const bool should_reexecute = jvms()->should_reexecute();
844 JVMState* youngest_jvms = should_reexecute ? sync_jvms_for_reexecute() : sync_jvms();
845
846 // NOTE: set_bci (called from sync_jvms) might reset the reexecute bit to
847 // undefined if the bci is different. This is normal for Parse but it
848 // should not happen for LibraryCallKit because only one bci is processed.
849 assert(!is_LibraryCallKit() || (jvms()->should_reexecute() == should_reexecute),
850 "in LibraryCallKit the reexecute bit should not change");
851
852 // If we are guaranteed to throw, we can prune everything but the
853 // input to the current bytecode.
854 bool can_prune_locals = false;
855 uint stack_slots_not_pruned = 0;
856 int inputs = 0, depth = 0;
857 if (must_throw) {
858 assert(method() == youngest_jvms->method(), "sanity");
859 if (compute_stack_effects(inputs, depth)) {
860 can_prune_locals = true;
861 stack_slots_not_pruned = inputs;
862 }
863 }
864
865 if (env()->jvmti_can_access_local_variables()) {
866 // At any safepoint, this method can get breakpointed, which would
867 // then require an immediate deoptimization.
868 can_prune_locals = false; // do not prune locals
869 stack_slots_not_pruned = 0;
870 }
871
872 // do not scribble on the input jvms
873 JVMState* out_jvms = youngest_jvms->clone_deep(C);
874 call->set_jvms(out_jvms); // Start jvms list for call node
875
876 // For a known set of bytecodes, the interpreter should reexecute them if
877 // deoptimization happens. We set the reexecute state for them here
878 if (out_jvms->is_reexecute_undefined() && //don't change if already specified
879 should_reexecute_implied_by_bytecode(out_jvms, call->is_AllocateArray())) {
880 out_jvms->set_should_reexecute(true); //NOTE: youngest_jvms not changed
881 }
882
883 // Presize the call:
884 DEBUG_ONLY(uint non_debug_edges = call->req());
885 call->add_req_batch(top(), youngest_jvms->debug_depth());
886 assert(call->req() == non_debug_edges + youngest_jvms->debug_depth(), "");
887
888 // Set up edges so that the call looks like this:
889 // Call [state:] ctl io mem fptr retadr
890 // [parms:] parm0 ... parmN
891 // [root:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
892 // [...mid:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN [...]
893 // [young:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
894 // Note that caller debug info precedes callee debug info.
895
896 // Fill pointer walks backwards from "young:" to "root:" in the diagram above:
897 uint debug_ptr = call->req();
898
899 // Loop over the map input edges associated with jvms, add them
900 // to the call node, & reset all offsets to match call node array.
901 for (JVMState* in_jvms = youngest_jvms; in_jvms != NULL; ) {
902 uint debug_end = debug_ptr;
903 uint debug_start = debug_ptr - in_jvms->debug_size();
904 debug_ptr = debug_start; // back up the ptr
905
906 uint p = debug_start; // walks forward in [debug_start, debug_end)
907 uint j, k, l;
908 SafePointNode* in_map = in_jvms->map();
909 out_jvms->set_map(call);
910
911 if (can_prune_locals) {
912 assert(in_jvms->method() == out_jvms->method(), "sanity");
913 // If the current throw can reach an exception handler in this JVMS,
914 // then we must keep everything live that can reach that handler.
915 // As a quick and dirty approximation, we look for any handlers at all.
916 if (in_jvms->method()->has_exception_handlers()) {
917 can_prune_locals = false;
918 }
919 }
920
921 // Add the Locals
922 k = in_jvms->locoff();
923 l = in_jvms->loc_size();
924 out_jvms->set_locoff(p);
925 if (!can_prune_locals) {
926 for (j = 0; j < l; j++)
927 call->set_req(p++, in_map->in(k+j));
928 } else {
929 p += l; // already set to top above by add_req_batch
930 }
931
932 // Add the Expression Stack
933 k = in_jvms->stkoff();
934 l = in_jvms->sp();
935 out_jvms->set_stkoff(p);
936 if (!can_prune_locals) {
937 for (j = 0; j < l; j++)
938 call->set_req(p++, in_map->in(k+j));
939 } else if (can_prune_locals && stack_slots_not_pruned != 0) {
940 // Divide stack into {S0,...,S1}, where S0 is set to top.
941 uint s1 = stack_slots_not_pruned;
942 stack_slots_not_pruned = 0; // for next iteration
943 if (s1 > l) s1 = l;
944 uint s0 = l - s1;
945 p += s0; // skip the tops preinstalled by add_req_batch
946 for (j = s0; j < l; j++)
947 call->set_req(p++, in_map->in(k+j));
948 } else {
949 p += l; // already set to top above by add_req_batch
950 }
951
952 // Add the Monitors
953 k = in_jvms->monoff();
954 l = in_jvms->mon_size();
955 out_jvms->set_monoff(p);
956 for (j = 0; j < l; j++)
957 call->set_req(p++, in_map->in(k+j));
958
959 // Copy any scalar object fields.
960 k = in_jvms->scloff();
961 l = in_jvms->scl_size();
962 out_jvms->set_scloff(p);
963 for (j = 0; j < l; j++)
964 call->set_req(p++, in_map->in(k+j));
965
966 // Finish the new jvms.
967 out_jvms->set_endoff(p);
968
969 assert(out_jvms->endoff() == debug_end, "fill ptr must match");
970 assert(out_jvms->depth() == in_jvms->depth(), "depth must match");
971 assert(out_jvms->loc_size() == in_jvms->loc_size(), "size must match");
972 assert(out_jvms->mon_size() == in_jvms->mon_size(), "size must match");
973 assert(out_jvms->scl_size() == in_jvms->scl_size(), "size must match");
974 assert(out_jvms->debug_size() == in_jvms->debug_size(), "size must match");
975
976 // Update the two tail pointers in parallel.
977 out_jvms = out_jvms->caller();
978 in_jvms = in_jvms->caller();
979 }
980
981 assert(debug_ptr == non_debug_edges, "debug info must fit exactly");
982
983 // Test the correctness of JVMState::debug_xxx accessors:
984 assert(call->jvms()->debug_start() == non_debug_edges, "");
985 assert(call->jvms()->debug_end() == call->req(), "");
986 assert(call->jvms()->debug_depth() == call->req() - non_debug_edges, "");
987 }
988
989 bool GraphKit::compute_stack_effects(int& inputs, int& depth) {
990 Bytecodes::Code code = java_bc();
991 if (code == Bytecodes::_wide) {
992 code = method()->java_code_at_bci(bci() + 1);
993 }
994
995 BasicType rtype = T_ILLEGAL;
996 int rsize = 0;
997
998 if (code != Bytecodes::_illegal) {
999 depth = Bytecodes::depth(code); // checkcast=0, athrow=-1
1000 rtype = Bytecodes::result_type(code); // checkcast=P, athrow=V
1001 if (rtype < T_CONFLICT)
1002 rsize = type2size[rtype];
1003 }
1004
1005 switch (code) {
1006 case Bytecodes::_illegal:
1007 return false;
1008
1009 case Bytecodes::_ldc:
1010 case Bytecodes::_ldc_w:
1011 case Bytecodes::_ldc2_w:
1012 inputs = 0;
1013 break;
1014
1015 case Bytecodes::_dup: inputs = 1; break;
1016 case Bytecodes::_dup_x1: inputs = 2; break;
1017 case Bytecodes::_dup_x2: inputs = 3; break;
1018 case Bytecodes::_dup2: inputs = 2; break;
1019 case Bytecodes::_dup2_x1: inputs = 3; break;
1020 case Bytecodes::_dup2_x2: inputs = 4; break;
1021 case Bytecodes::_swap: inputs = 2; break;
1022 case Bytecodes::_arraylength: inputs = 1; break;
1023
1024 case Bytecodes::_getstatic:
1025 case Bytecodes::_putstatic:
1026 case Bytecodes::_getfield:
1027 case Bytecodes::_putfield:
1028 {
1029 bool ignored_will_link;
1030 ciField* field = method()->get_field_at_bci(bci(), ignored_will_link);
1031 int size = field->type()->size();
1032 bool is_get = (depth >= 0), is_static = (depth & 1);
1033 inputs = (is_static ? 0 : 1);
1034 if (is_get) {
1035 depth = size - inputs;
1036 } else {
1037 inputs += size; // putxxx pops the value from the stack
1038 depth = - inputs;
1039 }
1040 }
1041 break;
1042
1043 case Bytecodes::_invokevirtual:
1044 case Bytecodes::_invokespecial:
1045 case Bytecodes::_invokestatic:
1046 case Bytecodes::_invokedynamic:
1047 case Bytecodes::_invokeinterface:
1048 {
1049 bool ignored_will_link;
1050 ciSignature* declared_signature = NULL;
1051 ciMethod* ignored_callee = method()->get_method_at_bci(bci(), ignored_will_link, &declared_signature);
1052 assert(declared_signature != NULL, "cannot be null");
1053 inputs = declared_signature->arg_size_for_bc(code);
1054 int size = declared_signature->return_type()->size();
1055 depth = size - inputs;
1056 }
1057 break;
1058
1059 case Bytecodes::_multianewarray:
1060 {
1061 ciBytecodeStream iter(method());
1062 iter.reset_to_bci(bci());
1063 iter.next();
1064 inputs = iter.get_dimensions();
1065 assert(rsize == 1, "");
1066 depth = rsize - inputs;
1067 }
1068 break;
1069
1070 case Bytecodes::_ireturn:
1071 case Bytecodes::_lreturn:
1072 case Bytecodes::_freturn:
1073 case Bytecodes::_dreturn:
1074 case Bytecodes::_areturn:
1075 assert(rsize = -depth, "");
1076 inputs = rsize;
1077 break;
1078
1079 case Bytecodes::_jsr:
1080 case Bytecodes::_jsr_w:
1081 inputs = 0;
1082 depth = 1; // S.B. depth=1, not zero
1083 break;
1084
1085 default:
1086 // bytecode produces a typed result
1087 inputs = rsize - depth;
1088 assert(inputs >= 0, "");
1089 break;
1090 }
1091
1092 #ifdef ASSERT
1093 // spot check
1094 int outputs = depth + inputs;
1095 assert(outputs >= 0, "sanity");
1096 switch (code) {
1097 case Bytecodes::_checkcast: assert(inputs == 1 && outputs == 1, ""); break;
1098 case Bytecodes::_athrow: assert(inputs == 1 && outputs == 0, ""); break;
1099 case Bytecodes::_aload_0: assert(inputs == 0 && outputs == 1, ""); break;
1100 case Bytecodes::_return: assert(inputs == 0 && outputs == 0, ""); break;
1101 case Bytecodes::_drem: assert(inputs == 4 && outputs == 2, ""); break;
1102 }
1103 #endif //ASSERT
1104
1105 return true;
1106 }
1107
1108
1109
1110 //------------------------------basic_plus_adr---------------------------------
1111 Node* GraphKit::basic_plus_adr(Node* base, Node* ptr, Node* offset) {
1112 // short-circuit a common case
1113 if (offset == intcon(0)) return ptr;
1114 return _gvn.transform( new (C) AddPNode(base, ptr, offset) );
1115 }
1116
1117 Node* GraphKit::ConvI2L(Node* offset) {
1118 // short-circuit a common case
1119 jint offset_con = find_int_con(offset, Type::OffsetBot);
1120 if (offset_con != Type::OffsetBot) {
1121 return longcon((jlong) offset_con);
1122 }
1123 return _gvn.transform( new (C) ConvI2LNode(offset));
1124 }
1125
1126 Node* GraphKit::ConvI2UL(Node* offset) {
1127 juint offset_con = (juint) find_int_con(offset, Type::OffsetBot);
1128 if (offset_con != (juint) Type::OffsetBot) {
1129 return longcon((julong) offset_con);
1130 }
1131 Node* conv = _gvn.transform( new (C) ConvI2LNode(offset));
1132 Node* mask = _gvn.transform( ConLNode::make(C, (julong) max_juint) );
1133 return _gvn.transform( new (C) AndLNode(conv, mask) );
1134 }
1135
1136 Node* GraphKit::ConvL2I(Node* offset) {
1137 // short-circuit a common case
1138 jlong offset_con = find_long_con(offset, (jlong)Type::OffsetBot);
1139 if (offset_con != (jlong)Type::OffsetBot) {
1140 return intcon((int) offset_con);
1141 }
1142 return _gvn.transform( new (C) ConvL2INode(offset));
1143 }
1144
1145 //-------------------------load_object_klass-----------------------------------
1146 Node* GraphKit::load_object_klass(Node* obj) {
1147 // Special-case a fresh allocation to avoid building nodes:
1148 Node* akls = AllocateNode::Ideal_klass(obj, &_gvn);
1149 if (akls != NULL) return akls;
1150 Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes());
1151 return _gvn.transform( LoadKlassNode::make(_gvn, immutable_memory(), k_adr, TypeInstPtr::KLASS) );
1152 }
1153
1154 //-------------------------load_array_length-----------------------------------
1155 Node* GraphKit::load_array_length(Node* array) {
1156 // Special-case a fresh allocation to avoid building nodes:
1157 AllocateArrayNode* alloc = AllocateArrayNode::Ideal_array_allocation(array, &_gvn);
1158 Node *alen;
1159 if (alloc == NULL) {
1160 Node *r_adr = basic_plus_adr(array, arrayOopDesc::length_offset_in_bytes());
1161 alen = _gvn.transform( new (C) LoadRangeNode(0, immutable_memory(), r_adr, TypeInt::POS));
1162 } else {
1163 alen = alloc->Ideal_length();
1164 Node* ccast = alloc->make_ideal_length(_gvn.type(array)->is_oopptr(), &_gvn);
1165 if (ccast != alen) {
1166 alen = _gvn.transform(ccast);
1167 }
1168 }
1169 return alen;
1170 }
1171
1172 //------------------------------do_null_check----------------------------------
1173 // Helper function to do a NULL pointer check. Returned value is
1174 // the incoming address with NULL casted away. You are allowed to use the
1175 // not-null value only if you are control dependent on the test.
1176 extern int explicit_null_checks_inserted,
1177 explicit_null_checks_elided;
1178 Node* GraphKit::null_check_common(Node* value, BasicType type,
1179 // optional arguments for variations:
1180 bool assert_null,
1181 Node* *null_control) {
1182 assert(!assert_null || null_control == NULL, "not both at once");
1183 if (stopped()) return top();
1184 if (!GenerateCompilerNullChecks && !assert_null && null_control == NULL) {
1185 // For some performance testing, we may wish to suppress null checking.
1186 value = cast_not_null(value); // Make it appear to be non-null (4962416).
1187 return value;
1188 }
1189 explicit_null_checks_inserted++;
1190
1191 // Construct NULL check
1192 Node *chk = NULL;
1193 switch(type) {
1194 case T_LONG : chk = new (C) CmpLNode(value, _gvn.zerocon(T_LONG)); break;
1195 case T_INT : chk = new (C) CmpINode(value, _gvn.intcon(0)); break;
1196 case T_ARRAY : // fall through
1197 type = T_OBJECT; // simplify further tests
1198 case T_OBJECT : {
1199 const Type *t = _gvn.type( value );
1200
1201 const TypeOopPtr* tp = t->isa_oopptr();
1202 if (tp != NULL && tp->klass() != NULL && !tp->klass()->is_loaded()
1203 // Only for do_null_check, not any of its siblings:
1204 && !assert_null && null_control == NULL) {
1205 // Usually, any field access or invocation on an unloaded oop type
1206 // will simply fail to link, since the statically linked class is
1207 // likely also to be unloaded. However, in -Xcomp mode, sometimes
1208 // the static class is loaded but the sharper oop type is not.
1209 // Rather than checking for this obscure case in lots of places,
1210 // we simply observe that a null check on an unloaded class
1211 // will always be followed by a nonsense operation, so we
1212 // can just issue the uncommon trap here.
1213 // Our access to the unloaded class will only be correct
1214 // after it has been loaded and initialized, which requires
1215 // a trip through the interpreter.
1216 #ifndef PRODUCT
1217 if (WizardMode) { tty->print("Null check of unloaded "); tp->klass()->print(); tty->cr(); }
1218 #endif
1219 uncommon_trap(Deoptimization::Reason_unloaded,
1220 Deoptimization::Action_reinterpret,
1221 tp->klass(), "!loaded");
1222 return top();
1223 }
1224
1225 if (assert_null) {
1226 // See if the type is contained in NULL_PTR.
1227 // If so, then the value is already null.
1228 if (t->higher_equal(TypePtr::NULL_PTR)) {
1229 explicit_null_checks_elided++;
1230 return value; // Elided null assert quickly!
1231 }
1232 } else {
1233 // See if mixing in the NULL pointer changes type.
1234 // If so, then the NULL pointer was not allowed in the original
1235 // type. In other words, "value" was not-null.
1236 if (t->meet(TypePtr::NULL_PTR) != t) {
1237 // same as: if (!TypePtr::NULL_PTR->higher_equal(t)) ...
1238 explicit_null_checks_elided++;
1239 return value; // Elided null check quickly!
1240 }
1241 }
1242 chk = new (C) CmpPNode( value, null() );
1243 break;
1244 }
1245
1246 default:
1247 fatal(err_msg_res("unexpected type: %s", type2name(type)));
1248 }
1249 assert(chk != NULL, "sanity check");
1250 chk = _gvn.transform(chk);
1251
1252 BoolTest::mask btest = assert_null ? BoolTest::eq : BoolTest::ne;
1253 BoolNode *btst = new (C) BoolNode( chk, btest);
1254 Node *tst = _gvn.transform( btst );
1255
1256 //-----------
1257 // if peephole optimizations occurred, a prior test existed.
1258 // If a prior test existed, maybe it dominates as we can avoid this test.
1259 if (tst != btst && type == T_OBJECT) {
1260 // At this point we want to scan up the CFG to see if we can
1261 // find an identical test (and so avoid this test altogether).
1262 Node *cfg = control();
1263 int depth = 0;
1264 while( depth < 16 ) { // Limit search depth for speed
1265 if( cfg->Opcode() == Op_IfTrue &&
1266 cfg->in(0)->in(1) == tst ) {
1267 // Found prior test. Use "cast_not_null" to construct an identical
1268 // CastPP (and hence hash to) as already exists for the prior test.
1269 // Return that casted value.
1270 if (assert_null) {
1271 replace_in_map(value, null());
1272 return null(); // do not issue the redundant test
1273 }
1274 Node *oldcontrol = control();
1275 set_control(cfg);
1276 Node *res = cast_not_null(value);
1277 set_control(oldcontrol);
1278 explicit_null_checks_elided++;
1279 return res;
1280 }
1281 cfg = IfNode::up_one_dom(cfg, /*linear_only=*/ true);
1282 if (cfg == NULL) break; // Quit at region nodes
1283 depth++;
1284 }
1285 }
1286
1287 //-----------
1288 // Branch to failure if null
1289 float ok_prob = PROB_MAX; // a priori estimate: nulls never happen
1290 Deoptimization::DeoptReason reason;
1291 if (assert_null)
1292 reason = Deoptimization::Reason_null_assert;
1293 else if (type == T_OBJECT)
1294 reason = Deoptimization::Reason_null_check;
1295 else
1296 reason = Deoptimization::Reason_div0_check;
1297
1298 // %%% Since Reason_unhandled is not recorded on a per-bytecode basis,
1299 // ciMethodData::has_trap_at will return a conservative -1 if any
1300 // must-be-null assertion has failed. This could cause performance
1301 // problems for a method after its first do_null_assert failure.
1302 // Consider using 'Reason_class_check' instead?
1303
1304 // To cause an implicit null check, we set the not-null probability
1305 // to the maximum (PROB_MAX). For an explicit check the probability
1306 // is set to a smaller value.
1307 if (null_control != NULL || too_many_traps(reason)) {
1308 // probability is less likely
1309 ok_prob = PROB_LIKELY_MAG(3);
1310 } else if (!assert_null &&
1311 (ImplicitNullCheckThreshold > 0) &&
1312 method() != NULL &&
1313 (method()->method_data()->trap_count(reason)
1314 >= (uint)ImplicitNullCheckThreshold)) {
1315 ok_prob = PROB_LIKELY_MAG(3);
1316 }
1317
1318 if (null_control != NULL) {
1319 IfNode* iff = create_and_map_if(control(), tst, ok_prob, COUNT_UNKNOWN);
1320 Node* null_true = _gvn.transform( new (C) IfFalseNode(iff));
1321 set_control( _gvn.transform( new (C) IfTrueNode(iff)));
1322 if (null_true == top())
1323 explicit_null_checks_elided++;
1324 (*null_control) = null_true;
1325 } else {
1326 BuildCutout unless(this, tst, ok_prob);
1327 // Check for optimizer eliding test at parse time
1328 if (stopped()) {
1329 // Failure not possible; do not bother making uncommon trap.
1330 explicit_null_checks_elided++;
1331 } else if (assert_null) {
1332 uncommon_trap(reason,
1333 Deoptimization::Action_make_not_entrant,
1334 NULL, "assert_null");
1335 } else {
1336 replace_in_map(value, zerocon(type));
1337 builtin_throw(reason);
1338 }
1339 }
1340
1341 // Must throw exception, fall-thru not possible?
1342 if (stopped()) {
1343 return top(); // No result
1344 }
1345
1346 if (assert_null) {
1347 // Cast obj to null on this path.
1348 replace_in_map(value, zerocon(type));
1349 return zerocon(type);
1350 }
1351
1352 // Cast obj to not-null on this path, if there is no null_control.
1353 // (If there is a null_control, a non-null value may come back to haunt us.)
1354 if (type == T_OBJECT) {
1355 Node* cast = cast_not_null(value, false);
1356 if (null_control == NULL || (*null_control) == top())
1357 replace_in_map(value, cast);
1358 value = cast;
1359 }
1360
1361 return value;
1362 }
1363
1364
1365 //------------------------------cast_not_null----------------------------------
1366 // Cast obj to not-null on this path
1367 Node* GraphKit::cast_not_null(Node* obj, bool do_replace_in_map) {
1368 const Type *t = _gvn.type(obj);
1369 const Type *t_not_null = t->join(TypePtr::NOTNULL);
1370 // Object is already not-null?
1371 if( t == t_not_null ) return obj;
1372
1373 Node *cast = new (C) CastPPNode(obj,t_not_null);
1374 cast->init_req(0, control());
1375 cast = _gvn.transform( cast );
1376
1377 // Scan for instances of 'obj' in the current JVM mapping.
1378 // These instances are known to be not-null after the test.
1379 if (do_replace_in_map)
1380 replace_in_map(obj, cast);
1381
1382 return cast; // Return casted value
1383 }
1384
1385
1386 //--------------------------replace_in_map-------------------------------------
1387 void GraphKit::replace_in_map(Node* old, Node* neww) {
1388 if (old == neww) {
1389 return;
1390 }
1391
1392 map()->replace_edge(old, neww);
1393
1394 // Note: This operation potentially replaces any edge
1395 // on the map. This includes locals, stack, and monitors
1396 // of the current (innermost) JVM state.
1397
1398 // don't let inconsistent types from profiling escape this
1399 // method
1400
1401 const Type* told = _gvn.type(old);
1402 const Type* tnew = _gvn.type(neww);
1403
1404 if (!tnew->higher_equal(told)) {
1405 return;
1406 }
1407
1408 map()->record_replaced_node(old, neww);
1409 }
1410
1411
1412 //=============================================================================
1413 //--------------------------------memory---------------------------------------
1414 Node* GraphKit::memory(uint alias_idx) {
1415 MergeMemNode* mem = merged_memory();
1416 Node* p = mem->memory_at(alias_idx);
1417 _gvn.set_type(p, Type::MEMORY); // must be mapped
1418 return p;
1419 }
1420
1421 //-----------------------------reset_memory------------------------------------
1422 Node* GraphKit::reset_memory() {
1423 Node* mem = map()->memory();
1424 // do not use this node for any more parsing!
1425 debug_only( map()->set_memory((Node*)NULL) );
1426 return _gvn.transform( mem );
1427 }
1428
1429 //------------------------------set_all_memory---------------------------------
1430 void GraphKit::set_all_memory(Node* newmem) {
1431 Node* mergemem = MergeMemNode::make(C, newmem);
1432 gvn().set_type_bottom(mergemem);
1433 map()->set_memory(mergemem);
1434 }
1435
1436 //------------------------------set_all_memory_call----------------------------
1437 void GraphKit::set_all_memory_call(Node* call, bool separate_io_proj) {
1438 Node* newmem = _gvn.transform( new (C) ProjNode(call, TypeFunc::Memory, separate_io_proj) );
1439 set_all_memory(newmem);
1440 }
1441
1442 //=============================================================================
1443 //
1444 // parser factory methods for MemNodes
1445 //
1446 // These are layered on top of the factory methods in LoadNode and StoreNode,
1447 // and integrate with the parser's memory state and _gvn engine.
1448 //
1449
1450 // factory methods in "int adr_idx"
1451 Node* GraphKit::make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
1452 int adr_idx,
1453 bool require_atomic_access, LoadNode::Sem sem) {
1454 assert(adr_idx != Compile::AliasIdxTop, "use other make_load factory" );
1455 const TypePtr* adr_type = NULL; // debug-mode-only argument
1456 debug_only(adr_type = C->get_adr_type(adr_idx));
1457 Node* mem = memory(adr_idx);
1458 Node* ld;
1459 if (require_atomic_access && bt == T_LONG) {
1460 ld = LoadLNode::make_atomic(C, ctl, mem, adr, adr_type, t, sem);
1461 } else {
1462 ld = LoadNode::make(_gvn, ctl, mem, adr, adr_type, t, bt, sem);
1463 }
1464 return _gvn.transform(ld);
1465 }
1466
1467 Node* GraphKit::store_to_memory(Node* ctl, Node* adr, Node *val, BasicType bt,
1468 int adr_idx,
1469 bool require_atomic_access,
1470 StoreNode::Sem sem) {
1471 assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1472 const TypePtr* adr_type = NULL;
1473 debug_only(adr_type = C->get_adr_type(adr_idx));
1474 Node *mem = memory(adr_idx);
1475 Node* st;
1476 if (require_atomic_access && bt == T_LONG) {
1477 st = StoreLNode::make_atomic(C, ctl, mem, adr, adr_type, val, sem);
1478 } else {
1479 st = StoreNode::make(_gvn, ctl, mem, adr, adr_type, val, bt, sem);
1480 }
1481 st = _gvn.transform(st);
1482 set_memory(st, adr_idx);
1483 // Back-to-back stores can only remove intermediate store with DU info
1484 // so push on worklist for optimizer.
1485 if (mem->req() > MemNode::Address && adr == mem->in(MemNode::Address))
1486 record_for_igvn(st);
1487
1488 return st;
1489 }
1490
1491
1492 void GraphKit::pre_barrier(bool do_load,
1493 Node* ctl,
1494 Node* obj,
1495 Node* adr,
1496 uint adr_idx,
1497 Node* val,
1498 const TypeOopPtr* val_type,
1499 Node* pre_val,
1500 BasicType bt) {
1501
1502 BarrierSet* bs = Universe::heap()->barrier_set();
1503 set_control(ctl);
1504 switch (bs->kind()) {
1505 case BarrierSet::G1SATBCT:
1506 case BarrierSet::G1SATBCTLogging:
1507 g1_write_barrier_pre(do_load, obj, adr, adr_idx, val, val_type, pre_val, bt);
1508 break;
1509
1510 case BarrierSet::CardTableModRef:
1511 case BarrierSet::CardTableExtension:
1512 case BarrierSet::ModRef:
1513 break;
1514
1515 case BarrierSet::Other:
1516 default :
1517 ShouldNotReachHere();
1518
1519 }
1520 }
1521
1522 void GraphKit::post_barrier(Node* ctl,
1523 Node* store,
1524 Node* obj,
1525 Node* adr,
1526 uint adr_idx,
1527 Node* val,
1528 BasicType bt,
1529 bool use_precise) {
1530 BarrierSet* bs = Universe::heap()->barrier_set();
1531 set_control(ctl);
1532 switch (bs->kind()) {
1533 case BarrierSet::G1SATBCT:
1534 case BarrierSet::G1SATBCTLogging:
1535 g1_write_barrier_post(store, obj, adr, adr_idx, val, bt, use_precise);
1536 break;
1537
1538 case BarrierSet::CardTableModRef:
1539 case BarrierSet::CardTableExtension:
1540 write_barrier_post(store, obj, adr, adr_idx, val, use_precise);
1541 break;
1542
1543 case BarrierSet::ModRef:
1544 break;
1545
1546 case BarrierSet::Other:
1547 default :
1548 ShouldNotReachHere();
1549
1550 }
1551 }
1552
1553 Node* GraphKit::store_oop(Node* ctl,
1554 Node* obj,
1555 Node* adr,
1556 const TypePtr* adr_type,
1557 Node* val,
1558 const TypeOopPtr* val_type,
1559 BasicType bt,
1560 bool use_precise,
1561 StoreNode::Sem sem) {
1562 // Transformation of a value which could be NULL pointer (CastPP #NULL)
1563 // could be delayed during Parse (for example, in adjust_map_after_if()).
1564 // Execute transformation here to avoid barrier generation in such case.
1565 if (_gvn.type(val) == TypePtr::NULL_PTR)
1566 val = _gvn.makecon(TypePtr::NULL_PTR);
1567
1568 set_control(ctl);
1569 if (stopped()) return top(); // Dead path ?
1570
1571 assert(bt == T_OBJECT, "sanity");
1572 assert(val != NULL, "not dead path");
1573 uint adr_idx = C->get_alias_index(adr_type);
1574 assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1575
1576 pre_barrier(true /* do_load */,
1577 control(), obj, adr, adr_idx, val, val_type,
1578 NULL /* pre_val */,
1579 bt);
1580
1581 Node* store = store_to_memory(control(), adr, val, bt, adr_idx, false, sem);
1582 post_barrier(control(), store, obj, adr, adr_idx, val, bt, use_precise);
1583 return store;
1584 }
1585
1586 // Could be an array or object we don't know at compile time (unsafe ref.)
1587 Node* GraphKit::store_oop_to_unknown(Node* ctl,
1588 Node* obj, // containing obj
1589 Node* adr, // actual adress to store val at
1590 const TypePtr* adr_type,
1591 Node* val,
1592 BasicType bt,
1593 StoreNode::Sem sem) {
1594 Compile::AliasType* at = C->alias_type(adr_type);
1595 const TypeOopPtr* val_type = NULL;
1596 if (adr_type->isa_instptr()) {
1597 if (at->field() != NULL) {
1598 // known field. This code is a copy of the do_put_xxx logic.
1599 ciField* field = at->field();
1600 if (!field->type()->is_loaded()) {
1601 val_type = TypeInstPtr::BOTTOM;
1602 } else {
1603 val_type = TypeOopPtr::make_from_klass(field->type()->as_klass());
1604 }
1605 }
1606 } else if (adr_type->isa_aryptr()) {
1607 val_type = adr_type->is_aryptr()->elem()->make_oopptr();
1608 }
1609 if (val_type == NULL) {
1610 val_type = TypeInstPtr::BOTTOM;
1611 }
1612 return store_oop(ctl, obj, adr, adr_type, val, val_type, bt, true, sem);
1613 }
1614
1615
1616 //-------------------------array_element_address-------------------------
1617 Node* GraphKit::array_element_address(Node* ary, Node* idx, BasicType elembt,
1618 const TypeInt* sizetype) {
1619 uint shift = exact_log2(type2aelembytes(elembt));
1620 uint header = arrayOopDesc::base_offset_in_bytes(elembt);
1621
1622 // short-circuit a common case (saves lots of confusing waste motion)
1623 jint idx_con = find_int_con(idx, -1);
1624 if (idx_con >= 0) {
1625 intptr_t offset = header + ((intptr_t)idx_con << shift);
1626 return basic_plus_adr(ary, offset);
1627 }
1628
1629 // must be correct type for alignment purposes
1630 Node* base = basic_plus_adr(ary, header);
1631 #ifdef _LP64
1632 // The scaled index operand to AddP must be a clean 64-bit value.
1633 // Java allows a 32-bit int to be incremented to a negative
1634 // value, which appears in a 64-bit register as a large
1635 // positive number. Using that large positive number as an
1636 // operand in pointer arithmetic has bad consequences.
1637 // On the other hand, 32-bit overflow is rare, and the possibility
1638 // can often be excluded, if we annotate the ConvI2L node with
1639 // a type assertion that its value is known to be a small positive
1640 // number. (The prior range check has ensured this.)
1641 // This assertion is used by ConvI2LNode::Ideal.
1642 int index_max = max_jint - 1; // array size is max_jint, index is one less
1643 if (sizetype != NULL) index_max = sizetype->_hi - 1;
1644 const TypeLong* lidxtype = TypeLong::make(CONST64(0), index_max, Type::WidenMax);
1645 idx = _gvn.transform( new (C) ConvI2LNode(idx, lidxtype) );
1646 #endif
1647 Node* scale = _gvn.transform( new (C) LShiftXNode(idx, intcon(shift)) );
1648 return basic_plus_adr(ary, base, scale);
1649 }
1650
1651 //-------------------------load_array_element-------------------------
1652 Node* GraphKit::load_array_element(Node* ctl, Node* ary, Node* idx, const TypeAryPtr* arytype) {
1653 const Type* elemtype = arytype->elem();
1654 BasicType elembt = elemtype->array_element_basic_type();
1655 Node* adr = array_element_address(ary, idx, elembt, arytype->size());
1656 Node* ld = make_load(ctl, adr, elemtype, elembt, arytype);
1657 return ld;
1658 }
1659
1660 //-------------------------set_arguments_for_java_call-------------------------
1661 // Arguments (pre-popped from the stack) are taken from the JVMS.
1662 void GraphKit::set_arguments_for_java_call(CallJavaNode* call) {
1663 // Add the call arguments:
1664 uint nargs = call->method()->arg_size();
1665 for (uint i = 0; i < nargs; i++) {
1666 Node* arg = argument(i);
1667 call->init_req(i + TypeFunc::Parms, arg);
1668 }
1669 }
1670
1671 //---------------------------set_edges_for_java_call---------------------------
1672 // Connect a newly created call into the current JVMS.
1673 // A return value node (if any) is returned from set_edges_for_java_call.
1674 void GraphKit::set_edges_for_java_call(CallJavaNode* call, bool must_throw, bool separate_io_proj) {
1675
1676 // Add the predefined inputs:
1677 call->init_req( TypeFunc::Control, control() );
1678 call->init_req( TypeFunc::I_O , i_o() );
1679 call->init_req( TypeFunc::Memory , reset_memory() );
1680 call->init_req( TypeFunc::FramePtr, frameptr() );
1681 call->init_req( TypeFunc::ReturnAdr, top() );
1682
1683 add_safepoint_edges(call, must_throw);
1684
1685 Node* xcall = _gvn.transform(call);
1686
1687 if (xcall == top()) {
1688 set_control(top());
1689 return;
1690 }
1691 assert(xcall == call, "call identity is stable");
1692
1693 // Re-use the current map to produce the result.
1694
1695 set_control(_gvn.transform(new (C) ProjNode(call, TypeFunc::Control)));
1696 set_i_o( _gvn.transform(new (C) ProjNode(call, TypeFunc::I_O , separate_io_proj)));
1697 set_all_memory_call(xcall, separate_io_proj);
1698
1699 //return xcall; // no need, caller already has it
1700 }
1701
1702 Node* GraphKit::set_results_for_java_call(CallJavaNode* call, bool separate_io_proj) {
1703 if (stopped()) return top(); // maybe the call folded up?
1704
1705 // Capture the return value, if any.
1706 Node* ret;
1707 if (call->method() == NULL ||
1708 call->method()->return_type()->basic_type() == T_VOID)
1709 ret = top();
1710 else ret = _gvn.transform(new (C) ProjNode(call, TypeFunc::Parms));
1711
1712 // Note: Since any out-of-line call can produce an exception,
1713 // we always insert an I_O projection from the call into the result.
1714
1715 make_slow_call_ex(call, env()->Throwable_klass(), separate_io_proj);
1716
1717 if (separate_io_proj) {
1718 // The caller requested separate projections be used by the fall
1719 // through and exceptional paths, so replace the projections for
1720 // the fall through path.
1721 set_i_o(_gvn.transform( new (C) ProjNode(call, TypeFunc::I_O) ));
1722 set_all_memory(_gvn.transform( new (C) ProjNode(call, TypeFunc::Memory) ));
1723 }
1724 return ret;
1725 }
1726
1727 //--------------------set_predefined_input_for_runtime_call--------------------
1728 // Reading and setting the memory state is way conservative here.
1729 // The real problem is that I am not doing real Type analysis on memory,
1730 // so I cannot distinguish card mark stores from other stores. Across a GC
1731 // point the Store Barrier and the card mark memory has to agree. I cannot
1732 // have a card mark store and its barrier split across the GC point from
1733 // either above or below. Here I get that to happen by reading ALL of memory.
1734 // A better answer would be to separate out card marks from other memory.
1735 // For now, return the input memory state, so that it can be reused
1736 // after the call, if this call has restricted memory effects.
1737 Node* GraphKit::set_predefined_input_for_runtime_call(SafePointNode* call) {
1738 // Set fixed predefined input arguments
1739 Node* memory = reset_memory();
1740 call->init_req( TypeFunc::Control, control() );
1741 call->init_req( TypeFunc::I_O, top() ); // does no i/o
1742 call->init_req( TypeFunc::Memory, memory ); // may gc ptrs
1743 call->init_req( TypeFunc::FramePtr, frameptr() );
1744 call->init_req( TypeFunc::ReturnAdr, top() );
1745 return memory;
1746 }
1747
1748 //-------------------set_predefined_output_for_runtime_call--------------------
1749 // Set control and memory (not i_o) from the call.
1750 // If keep_mem is not NULL, use it for the output state,
1751 // except for the RawPtr output of the call, if hook_mem is TypeRawPtr::BOTTOM.
1752 // If hook_mem is NULL, this call produces no memory effects at all.
1753 // If hook_mem is a Java-visible memory slice (such as arraycopy operands),
1754 // then only that memory slice is taken from the call.
1755 // In the last case, we must put an appropriate memory barrier before
1756 // the call, so as to create the correct anti-dependencies on loads
1757 // preceding the call.
1758 void GraphKit::set_predefined_output_for_runtime_call(Node* call,
1759 Node* keep_mem,
1760 const TypePtr* hook_mem) {
1761 // no i/o
1762 set_control(_gvn.transform( new (C) ProjNode(call,TypeFunc::Control) ));
1763 if (keep_mem) {
1764 // First clone the existing memory state
1765 set_all_memory(keep_mem);
1766 if (hook_mem != NULL) {
1767 // Make memory for the call
1768 Node* mem = _gvn.transform( new (C) ProjNode(call, TypeFunc::Memory) );
1769 // Set the RawPtr memory state only. This covers all the heap top/GC stuff
1770 // We also use hook_mem to extract specific effects from arraycopy stubs.
1771 set_memory(mem, hook_mem);
1772 }
1773 // ...else the call has NO memory effects.
1774
1775 // Make sure the call advertises its memory effects precisely.
1776 // This lets us build accurate anti-dependences in gcm.cpp.
1777 assert(C->alias_type(call->adr_type()) == C->alias_type(hook_mem),
1778 "call node must be constructed correctly");
1779 } else {
1780 assert(hook_mem == NULL, "");
1781 // This is not a "slow path" call; all memory comes from the call.
1782 set_all_memory_call(call);
1783 }
1784 }
1785
1786
1787 // Replace the call with the current state of the kit.
1788 void GraphKit::replace_call(CallNode* call, Node* result, bool do_replaced_nodes) {
1789 JVMState* ejvms = NULL;
1790 if (has_exceptions()) {
1791 ejvms = transfer_exceptions_into_jvms();
1792 }
1793
1794 ReplacedNodes replaced_nodes = map()->replaced_nodes();
1795 ReplacedNodes replaced_nodes_exception;
1796 Node* ex_ctl = top();
1797
1798 SafePointNode* final_state = stop();
1799
1800 // Find all the needed outputs of this call
1801 CallProjections callprojs;
1802 call->extract_projections(&callprojs, true);
1803
1804 Node* init_mem = call->in(TypeFunc::Memory);
1805 Node* final_mem = final_state->in(TypeFunc::Memory);
1806 Node* final_ctl = final_state->in(TypeFunc::Control);
1807 Node* final_io = final_state->in(TypeFunc::I_O);
1808
1809 // Replace all the old call edges with the edges from the inlining result
1810 if (callprojs.fallthrough_catchproj != NULL) {
1811 C->gvn_replace_by(callprojs.fallthrough_catchproj, final_ctl);
1812 }
1813 if (callprojs.fallthrough_memproj != NULL) {
1814 if (final_mem->is_MergeMem()) {
1815 // Parser's exits MergeMem was not transformed but may be optimized
1816 final_mem = _gvn.transform(final_mem);
1817 }
1818 C->gvn_replace_by(callprojs.fallthrough_memproj, final_mem);
1819 }
1820 if (callprojs.fallthrough_ioproj != NULL) {
1821 C->gvn_replace_by(callprojs.fallthrough_ioproj, final_io);
1822 }
1823
1824 // Replace the result with the new result if it exists and is used
1825 if (callprojs.resproj != NULL && result != NULL) {
1826 C->gvn_replace_by(callprojs.resproj, result);
1827 }
1828
1829 if (ejvms == NULL) {
1830 // No exception edges to simply kill off those paths
1831 if (callprojs.catchall_catchproj != NULL) {
1832 C->gvn_replace_by(callprojs.catchall_catchproj, C->top());
1833 }
1834 if (callprojs.catchall_memproj != NULL) {
1835 C->gvn_replace_by(callprojs.catchall_memproj, C->top());
1836 }
1837 if (callprojs.catchall_ioproj != NULL) {
1838 C->gvn_replace_by(callprojs.catchall_ioproj, C->top());
1839 }
1840 // Replace the old exception object with top
1841 if (callprojs.exobj != NULL) {
1842 C->gvn_replace_by(callprojs.exobj, C->top());
1843 }
1844 } else {
1845 GraphKit ekit(ejvms);
1846
1847 // Load my combined exception state into the kit, with all phis transformed:
1848 SafePointNode* ex_map = ekit.combine_and_pop_all_exception_states();
1849 replaced_nodes_exception = ex_map->replaced_nodes();
1850
1851 Node* ex_oop = ekit.use_exception_state(ex_map);
1852
1853 if (callprojs.catchall_catchproj != NULL) {
1854 C->gvn_replace_by(callprojs.catchall_catchproj, ekit.control());
1855 ex_ctl = ekit.control();
1856 }
1857 if (callprojs.catchall_memproj != NULL) {
1858 C->gvn_replace_by(callprojs.catchall_memproj, ekit.reset_memory());
1859 }
1860 if (callprojs.catchall_ioproj != NULL) {
1861 C->gvn_replace_by(callprojs.catchall_ioproj, ekit.i_o());
1862 }
1863
1864 // Replace the old exception object with the newly created one
1865 if (callprojs.exobj != NULL) {
1866 C->gvn_replace_by(callprojs.exobj, ex_oop);
1867 }
1868 }
1869
1870 // Disconnect the call from the graph
1871 call->disconnect_inputs(NULL, C);
1872 C->gvn_replace_by(call, C->top());
1873
1874 // Clean up any MergeMems that feed other MergeMems since the
1875 // optimizer doesn't like that.
1876 if (final_mem->is_MergeMem()) {
1877 Node_List wl;
1878 for (SimpleDUIterator i(final_mem); i.has_next(); i.next()) {
1879 Node* m = i.get();
1880 if (m->is_MergeMem() && !wl.contains(m)) {
1881 wl.push(m);
1882 }
1883 }
1884 while (wl.size() > 0) {
1885 _gvn.transform(wl.pop());
1886 }
1887 }
1888
1889 if (callprojs.fallthrough_catchproj != NULL && !final_ctl->is_top() && do_replaced_nodes) {
1890 replaced_nodes.apply(C, final_ctl);
1891 }
1892 if (!ex_ctl->is_top() && do_replaced_nodes) {
1893 replaced_nodes_exception.apply(C, ex_ctl);
1894 }
1895 }
1896
1897
1898 //------------------------------increment_counter------------------------------
1899 // for statistics: increment a VM counter by 1
1900
1901 void GraphKit::increment_counter(address counter_addr) {
1902 Node* adr1 = makecon(TypeRawPtr::make(counter_addr));
1903 increment_counter(adr1);
1904 }
1905
1906 void GraphKit::increment_counter(Node* counter_addr) {
1907 int adr_type = Compile::AliasIdxRaw;
1908 Node* ctrl = control();
1909 Node* cnt = make_load(ctrl, counter_addr, TypeInt::INT, T_INT, adr_type);
1910 Node* incr = _gvn.transform(new (C) AddINode(cnt, _gvn.intcon(1)));
1911 store_to_memory( ctrl, counter_addr, incr, T_INT, adr_type );
1912 }
1913
1914
1915 //------------------------------uncommon_trap----------------------------------
1916 // Bail out to the interpreter in mid-method. Implemented by calling the
1917 // uncommon_trap blob. This helper function inserts a runtime call with the
1918 // right debug info.
1919 void GraphKit::uncommon_trap(int trap_request,
1920 ciKlass* klass, const char* comment,
1921 bool must_throw,
1922 bool keep_exact_action) {
1923 if (failing()) stop();
1924 if (stopped()) return; // trap reachable?
1925
1926 // Note: If ProfileTraps is true, and if a deopt. actually
1927 // occurs here, the runtime will make sure an MDO exists. There is
1928 // no need to call method()->ensure_method_data() at this point.
1929
1930 // Set the stack pointer to the right value for reexecution:
1931 set_sp(reexecute_sp());
1932
1933 #ifdef ASSERT
1934 if (!must_throw) {
1935 // Make sure the stack has at least enough depth to execute
1936 // the current bytecode.
1937 int inputs, ignored_depth;
1938 if (compute_stack_effects(inputs, ignored_depth)) {
1939 assert(sp() >= inputs, err_msg_res("must have enough JVMS stack to execute %s: sp=%d, inputs=%d",
1940 Bytecodes::name(java_bc()), sp(), inputs));
1941 }
1942 }
1943 #endif
1944
1945 Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
1946 Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
1947
1948 switch (action) {
1949 case Deoptimization::Action_maybe_recompile:
1950 case Deoptimization::Action_reinterpret:
1951 // Temporary fix for 6529811 to allow virtual calls to be sure they
1952 // get the chance to go from mono->bi->mega
1953 if (!keep_exact_action &&
1954 Deoptimization::trap_request_index(trap_request) < 0 &&
1955 too_many_recompiles(reason)) {
1956 // This BCI is causing too many recompilations.
1957 action = Deoptimization::Action_none;
1958 trap_request = Deoptimization::make_trap_request(reason, action);
1959 } else {
1960 C->set_trap_can_recompile(true);
1961 }
1962 break;
1963 case Deoptimization::Action_make_not_entrant:
1964 C->set_trap_can_recompile(true);
1965 break;
1966 #ifdef ASSERT
1967 case Deoptimization::Action_none:
1968 case Deoptimization::Action_make_not_compilable:
1969 break;
1970 default:
1971 fatal(err_msg_res("unknown action %d: %s", action, Deoptimization::trap_action_name(action)));
1972 break;
1973 #endif
1974 }
1975
1976 if (TraceOptoParse) {
1977 char buf[100];
1978 tty->print_cr("Uncommon trap %s at bci:%d",
1979 Deoptimization::format_trap_request(buf, sizeof(buf),
1980 trap_request), bci());
1981 }
1982
1983 CompileLog* log = C->log();
1984 if (log != NULL) {
1985 int kid = (klass == NULL)? -1: log->identify(klass);
1986 log->begin_elem("uncommon_trap bci='%d'", bci());
1987 char buf[100];
1988 log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf),
1989 trap_request));
1990 if (kid >= 0) log->print(" klass='%d'", kid);
1991 if (comment != NULL) log->print(" comment='%s'", comment);
1992 log->end_elem();
1993 }
1994
1995 // Make sure any guarding test views this path as very unlikely
1996 Node *i0 = control()->in(0);
1997 if (i0 != NULL && i0->is_If()) { // Found a guarding if test?
1998 IfNode *iff = i0->as_If();
1999 float f = iff->_prob; // Get prob
2000 if (control()->Opcode() == Op_IfTrue) {
2001 if (f > PROB_UNLIKELY_MAG(4))
2002 iff->_prob = PROB_MIN;
2003 } else {
2004 if (f < PROB_LIKELY_MAG(4))
2005 iff->_prob = PROB_MAX;
2006 }
2007 }
2008
2009 // Clear out dead values from the debug info.
2010 kill_dead_locals();
2011
2012 // Now insert the uncommon trap subroutine call
2013 address call_addr = SharedRuntime::uncommon_trap_blob()->entry_point();
2014 const TypePtr* no_memory_effects = NULL;
2015 // Pass the index of the class to be loaded
2016 Node* call = make_runtime_call(RC_NO_LEAF | RC_UNCOMMON |
2017 (must_throw ? RC_MUST_THROW : 0),
2018 OptoRuntime::uncommon_trap_Type(),
2019 call_addr, "uncommon_trap", no_memory_effects,
2020 intcon(trap_request));
2021 assert(call->as_CallStaticJava()->uncommon_trap_request() == trap_request,
2022 "must extract request correctly from the graph");
2023 assert(trap_request != 0, "zero value reserved by uncommon_trap_request");
2024
2025 call->set_req(TypeFunc::ReturnAdr, returnadr());
2026 // The debug info is the only real input to this call.
2027
2028 // Halt-and-catch fire here. The above call should never return!
2029 HaltNode* halt = new(C) HaltNode(control(), frameptr());
2030 _gvn.set_type_bottom(halt);
2031 root()->add_req(halt);
2032
2033 stop_and_kill_map();
2034 }
2035
2036
2037 //--------------------------just_allocated_object------------------------------
2038 // Report the object that was just allocated.
2039 // It must be the case that there are no intervening safepoints.
2040 // We use this to determine if an object is so "fresh" that
2041 // it does not require card marks.
2042 Node* GraphKit::just_allocated_object(Node* current_control) {
2043 if (C->recent_alloc_ctl() == current_control)
2044 return C->recent_alloc_obj();
2045 return NULL;
2046 }
2047
2048
2049 void GraphKit::round_double_arguments(ciMethod* dest_method) {
2050 // (Note: TypeFunc::make has a cache that makes this fast.)
2051 const TypeFunc* tf = TypeFunc::make(dest_method);
2052 int nargs = tf->_domain->_cnt - TypeFunc::Parms;
2053 for (int j = 0; j < nargs; j++) {
2054 const Type *targ = tf->_domain->field_at(j + TypeFunc::Parms);
2055 if( targ->basic_type() == T_DOUBLE ) {
2056 // If any parameters are doubles, they must be rounded before
2057 // the call, dstore_rounding does gvn.transform
2058 Node *arg = argument(j);
2059 arg = dstore_rounding(arg);
2060 set_argument(j, arg);
2061 }
2062 }
2063 }
2064
2065 void GraphKit::round_double_result(ciMethod* dest_method) {
2066 // A non-strict method may return a double value which has an extended
2067 // exponent, but this must not be visible in a caller which is 'strict'
2068 // If a strict caller invokes a non-strict callee, round a double result
2069
2070 BasicType result_type = dest_method->return_type()->basic_type();
2071 assert( method() != NULL, "must have caller context");
2072 if( result_type == T_DOUBLE && method()->is_strict() && !dest_method->is_strict() ) {
2073 // Destination method's return value is on top of stack
2074 // dstore_rounding() does gvn.transform
2075 Node *result = pop_pair();
2076 result = dstore_rounding(result);
2077 push_pair(result);
2078 }
2079 }
2080
2081 // rounding for strict float precision conformance
2082 Node* GraphKit::precision_rounding(Node* n) {
2083 return UseStrictFP && _method->flags().is_strict()
2084 && UseSSE == 0 && Matcher::strict_fp_requires_explicit_rounding
2085 ? _gvn.transform( new (C) RoundFloatNode(0, n) )
2086 : n;
2087 }
2088
2089 // rounding for strict double precision conformance
2090 Node* GraphKit::dprecision_rounding(Node *n) {
2091 return UseStrictFP && _method->flags().is_strict()
2092 && UseSSE <= 1 && Matcher::strict_fp_requires_explicit_rounding
2093 ? _gvn.transform( new (C) RoundDoubleNode(0, n) )
2094 : n;
2095 }
2096
2097 // rounding for non-strict double stores
2098 Node* GraphKit::dstore_rounding(Node* n) {
2099 return Matcher::strict_fp_requires_explicit_rounding
2100 && UseSSE <= 1
2101 ? _gvn.transform( new (C) RoundDoubleNode(0, n) )
2102 : n;
2103 }
2104
2105 //=============================================================================
2106 // Generate a fast path/slow path idiom. Graph looks like:
2107 // [foo] indicates that 'foo' is a parameter
2108 //
2109 // [in] NULL
2110 // \ /
2111 // CmpP
2112 // Bool ne
2113 // If
2114 // / \
2115 // True False-<2>
2116 // / |
2117 // / cast_not_null
2118 // Load | | ^
2119 // [fast_test] | |
2120 // gvn to opt_test | |
2121 // / \ | <1>
2122 // True False |
2123 // | \\ |
2124 // [slow_call] \[fast_result]
2125 // Ctl Val \ \
2126 // | \ \
2127 // Catch <1> \ \
2128 // / \ ^ \ \
2129 // Ex No_Ex | \ \
2130 // | \ \ | \ <2> \
2131 // ... \ [slow_res] | | \ [null_result]
2132 // \ \--+--+--- | |
2133 // \ | / \ | /
2134 // --------Region Phi
2135 //
2136 //=============================================================================
2137 // Code is structured as a series of driver functions all called 'do_XXX' that
2138 // call a set of helper functions. Helper functions first, then drivers.
2139
2140 //------------------------------null_check_oop---------------------------------
2141 // Null check oop. Set null-path control into Region in slot 3.
2142 // Make a cast-not-nullness use the other not-null control. Return cast.
2143 Node* GraphKit::null_check_oop(Node* value, Node* *null_control,
2144 bool never_see_null) {
2145 // Initial NULL check taken path
2146 (*null_control) = top();
2147 Node* cast = null_check_common(value, T_OBJECT, false, null_control);
2148
2149 // Generate uncommon_trap:
2150 if (never_see_null && (*null_control) != top()) {
2151 // If we see an unexpected null at a check-cast we record it and force a
2152 // recompile; the offending check-cast will be compiled to handle NULLs.
2153 // If we see more than one offending BCI, then all checkcasts in the
2154 // method will be compiled to handle NULLs.
2155 PreserveJVMState pjvms(this);
2156 set_control(*null_control);
2157 replace_in_map(value, null());
2158 uncommon_trap(Deoptimization::Reason_null_check,
2159 Deoptimization::Action_make_not_entrant);
2160 (*null_control) = top(); // NULL path is dead
2161 }
2162
2163 // Cast away null-ness on the result
2164 return cast;
2165 }
2166
2167 //------------------------------opt_iff----------------------------------------
2168 // Optimize the fast-check IfNode. Set the fast-path region slot 2.
2169 // Return slow-path control.
2170 Node* GraphKit::opt_iff(Node* region, Node* iff) {
2171 IfNode *opt_iff = _gvn.transform(iff)->as_If();
2172
2173 // Fast path taken; set region slot 2
2174 Node *fast_taken = _gvn.transform( new (C) IfFalseNode(opt_iff) );
2175 region->init_req(2,fast_taken); // Capture fast-control
2176
2177 // Fast path not-taken, i.e. slow path
2178 Node *slow_taken = _gvn.transform( new (C) IfTrueNode(opt_iff) );
2179 return slow_taken;
2180 }
2181
2182 //-----------------------------make_runtime_call-------------------------------
2183 Node* GraphKit::make_runtime_call(int flags,
2184 const TypeFunc* call_type, address call_addr,
2185 const char* call_name,
2186 const TypePtr* adr_type,
2187 // The following parms are all optional.
2188 // The first NULL ends the list.
2189 Node* parm0, Node* parm1,
2190 Node* parm2, Node* parm3,
2191 Node* parm4, Node* parm5,
2192 Node* parm6, Node* parm7) {
2193 // Slow-path call
2194 bool is_leaf = !(flags & RC_NO_LEAF);
2195 bool has_io = (!is_leaf && !(flags & RC_NO_IO));
2196 if (call_name == NULL) {
2197 assert(!is_leaf, "must supply name for leaf");
2198 call_name = OptoRuntime::stub_name(call_addr);
2199 }
2200 CallNode* call;
2201 if (!is_leaf) {
2202 call = new(C) CallStaticJavaNode(call_type, call_addr, call_name,
2203 bci(), adr_type);
2204 } else if (flags & RC_NO_FP) {
2205 call = new(C) CallLeafNoFPNode(call_type, call_addr, call_name, adr_type);
2206 } else {
2207 call = new(C) CallLeafNode(call_type, call_addr, call_name, adr_type);
2208 }
2209
2210 // The following is similar to set_edges_for_java_call,
2211 // except that the memory effects of the call are restricted to AliasIdxRaw.
2212
2213 // Slow path call has no side-effects, uses few values
2214 bool wide_in = !(flags & RC_NARROW_MEM);
2215 bool wide_out = (C->get_alias_index(adr_type) == Compile::AliasIdxBot);
2216
2217 Node* prev_mem = NULL;
2218 if (wide_in) {
2219 prev_mem = set_predefined_input_for_runtime_call(call);
2220 } else {
2221 assert(!wide_out, "narrow in => narrow out");
2222 Node* narrow_mem = memory(adr_type);
2223 prev_mem = reset_memory();
2224 map()->set_memory(narrow_mem);
2225 set_predefined_input_for_runtime_call(call);
2226 }
2227
2228 // Hook each parm in order. Stop looking at the first NULL.
2229 if (parm0 != NULL) { call->init_req(TypeFunc::Parms+0, parm0);
2230 if (parm1 != NULL) { call->init_req(TypeFunc::Parms+1, parm1);
2231 if (parm2 != NULL) { call->init_req(TypeFunc::Parms+2, parm2);
2232 if (parm3 != NULL) { call->init_req(TypeFunc::Parms+3, parm3);
2233 if (parm4 != NULL) { call->init_req(TypeFunc::Parms+4, parm4);
2234 if (parm5 != NULL) { call->init_req(TypeFunc::Parms+5, parm5);
2235 if (parm6 != NULL) { call->init_req(TypeFunc::Parms+6, parm6);
2236 if (parm7 != NULL) { call->init_req(TypeFunc::Parms+7, parm7);
2237 /* close each nested if ===> */ } } } } } } } }
2238 assert(call->in(call->req()-1) != NULL, "must initialize all parms");
2239
2240 if (!is_leaf) {
2241 // Non-leaves can block and take safepoints:
2242 add_safepoint_edges(call, ((flags & RC_MUST_THROW) != 0));
2243 }
2244 // Non-leaves can throw exceptions:
2245 if (has_io) {
2246 call->set_req(TypeFunc::I_O, i_o());
2247 }
2248
2249 if (flags & RC_UNCOMMON) {
2250 // Set the count to a tiny probability. Cf. Estimate_Block_Frequency.
2251 // (An "if" probability corresponds roughly to an unconditional count.
2252 // Sort of.)
2253 call->set_cnt(PROB_UNLIKELY_MAG(4));
2254 }
2255
2256 Node* c = _gvn.transform(call);
2257 assert(c == call, "cannot disappear");
2258
2259 if (wide_out) {
2260 // Slow path call has full side-effects.
2261 set_predefined_output_for_runtime_call(call);
2262 } else {
2263 // Slow path call has few side-effects, and/or sets few values.
2264 set_predefined_output_for_runtime_call(call, prev_mem, adr_type);
2265 }
2266
2267 if (has_io) {
2268 set_i_o(_gvn.transform(new (C) ProjNode(call, TypeFunc::I_O)));
2269 }
2270 return call;
2271
2272 }
2273
2274 //------------------------------merge_memory-----------------------------------
2275 // Merge memory from one path into the current memory state.
2276 void GraphKit::merge_memory(Node* new_mem, Node* region, int new_path) {
2277 for (MergeMemStream mms(merged_memory(), new_mem->as_MergeMem()); mms.next_non_empty2(); ) {
2278 Node* old_slice = mms.force_memory();
2279 Node* new_slice = mms.memory2();
2280 if (old_slice != new_slice) {
2281 PhiNode* phi;
2282 if (new_slice->is_Phi() && new_slice->as_Phi()->region() == region) {
2283 phi = new_slice->as_Phi();
2284 #ifdef ASSERT
2285 if (old_slice->is_Phi() && old_slice->as_Phi()->region() == region)
2286 old_slice = old_slice->in(new_path);
2287 // Caller is responsible for ensuring that any pre-existing
2288 // phis are already aware of old memory.
2289 int old_path = (new_path > 1) ? 1 : 2; // choose old_path != new_path
2290 assert(phi->in(old_path) == old_slice, "pre-existing phis OK");
2291 #endif
2292 mms.set_memory(phi);
2293 } else {
2294 phi = PhiNode::make(region, old_slice, Type::MEMORY, mms.adr_type(C));
2295 _gvn.set_type(phi, Type::MEMORY);
2296 phi->set_req(new_path, new_slice);
2297 mms.set_memory(_gvn.transform(phi)); // assume it is complete
2298 }
2299 }
2300 }
2301 }
2302
2303 //------------------------------make_slow_call_ex------------------------------
2304 // Make the exception handler hookups for the slow call
2305 void GraphKit::make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj) {
2306 if (stopped()) return;
2307
2308 // Make a catch node with just two handlers: fall-through and catch-all
2309 Node* i_o = _gvn.transform( new (C) ProjNode(call, TypeFunc::I_O, separate_io_proj) );
2310 Node* catc = _gvn.transform( new (C) CatchNode(control(), i_o, 2) );
2311 Node* norm = _gvn.transform( new (C) CatchProjNode(catc, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci) );
2312 Node* excp = _gvn.transform( new (C) CatchProjNode(catc, CatchProjNode::catch_all_index, CatchProjNode::no_handler_bci) );
2313
2314 { PreserveJVMState pjvms(this);
2315 set_control(excp);
2316 set_i_o(i_o);
2317
2318 if (excp != top()) {
2319 // Create an exception state also.
2320 // Use an exact type if the caller has specified a specific exception.
2321 const Type* ex_type = TypeOopPtr::make_from_klass_unique(ex_klass)->cast_to_ptr_type(TypePtr::NotNull);
2322 Node* ex_oop = new (C) CreateExNode(ex_type, control(), i_o);
2323 add_exception_state(make_exception_state(_gvn.transform(ex_oop)));
2324 }
2325 }
2326
2327 // Get the no-exception control from the CatchNode.
2328 set_control(norm);
2329 }
2330
2331
2332 //-------------------------------gen_subtype_check-----------------------------
2333 // Generate a subtyping check. Takes as input the subtype and supertype.
2334 // Returns 2 values: sets the default control() to the true path and returns
2335 // the false path. Only reads invariant memory; sets no (visible) memory.
2336 // The PartialSubtypeCheckNode sets the hidden 1-word cache in the encoding
2337 // but that's not exposed to the optimizer. This call also doesn't take in an
2338 // Object; if you wish to check an Object you need to load the Object's class
2339 // prior to coming here.
2340 Node* GraphKit::gen_subtype_check(Node* subklass, Node* superklass) {
2341 // Fast check for identical types, perhaps identical constants.
2342 // The types can even be identical non-constants, in cases
2343 // involving Array.newInstance, Object.clone, etc.
2344 if (subklass == superklass)
2345 return top(); // false path is dead; no test needed.
2346
2347 if (_gvn.type(superklass)->singleton()) {
2348 ciKlass* superk = _gvn.type(superklass)->is_klassptr()->klass();
2349 ciKlass* subk = _gvn.type(subklass)->is_klassptr()->klass();
2350
2351 // In the common case of an exact superklass, try to fold up the
2352 // test before generating code. You may ask, why not just generate
2353 // the code and then let it fold up? The answer is that the generated
2354 // code will necessarily include null checks, which do not always
2355 // completely fold away. If they are also needless, then they turn
2356 // into a performance loss. Example:
2357 // Foo[] fa = blah(); Foo x = fa[0]; fa[1] = x;
2358 // Here, the type of 'fa' is often exact, so the store check
2359 // of fa[1]=x will fold up, without testing the nullness of x.
2360 switch (static_subtype_check(superk, subk)) {
2361 case SSC_always_false:
2362 {
2363 Node* always_fail = control();
2364 set_control(top());
2365 return always_fail;
2366 }
2367 case SSC_always_true:
2368 return top();
2369 case SSC_easy_test:
2370 {
2371 // Just do a direct pointer compare and be done.
2372 Node* cmp = _gvn.transform( new(C) CmpPNode(subklass, superklass) );
2373 Node* bol = _gvn.transform( new(C) BoolNode(cmp, BoolTest::eq) );
2374 IfNode* iff = create_and_xform_if(control(), bol, PROB_STATIC_FREQUENT, COUNT_UNKNOWN);
2375 set_control( _gvn.transform( new(C) IfTrueNode (iff) ) );
2376 return _gvn.transform( new(C) IfFalseNode(iff) );
2377 }
2378 case SSC_full_test:
2379 break;
2380 default:
2381 ShouldNotReachHere();
2382 }
2383 }
2384
2385 // %%% Possible further optimization: Even if the superklass is not exact,
2386 // if the subklass is the unique subtype of the superklass, the check
2387 // will always succeed. We could leave a dependency behind to ensure this.
2388
2389 // First load the super-klass's check-offset
2390 Node *p1 = basic_plus_adr( superklass, superklass, in_bytes(Klass::super_check_offset_offset()) );
2391 Node *chk_off = _gvn.transform( new (C) LoadINode( NULL, memory(p1), p1, _gvn.type(p1)->is_ptr() ) );
2392 int cacheoff_con = in_bytes(Klass::secondary_super_cache_offset());
2393 bool might_be_cache = (find_int_con(chk_off, cacheoff_con) == cacheoff_con);
2394
2395 // Load from the sub-klass's super-class display list, or a 1-word cache of
2396 // the secondary superclass list, or a failing value with a sentinel offset
2397 // if the super-klass is an interface or exceptionally deep in the Java
2398 // hierarchy and we have to scan the secondary superclass list the hard way.
2399 // Worst-case type is a little odd: NULL is allowed as a result (usually
2400 // klass loads can never produce a NULL).
2401 Node *chk_off_X = ConvI2X(chk_off);
2402 Node *p2 = _gvn.transform( new (C) AddPNode(subklass,subklass,chk_off_X) );
2403 // For some types like interfaces the following loadKlass is from a 1-word
2404 // cache which is mutable so can't use immutable memory. Other
2405 // types load from the super-class display table which is immutable.
2406 Node *kmem = might_be_cache ? memory(p2) : immutable_memory();
2407 Node *nkls = _gvn.transform( LoadKlassNode::make( _gvn, kmem, p2, _gvn.type(p2)->is_ptr(), TypeKlassPtr::OBJECT_OR_NULL ) );
2408
2409 // Compile speed common case: ARE a subtype and we canNOT fail
2410 if( superklass == nkls )
2411 return top(); // false path is dead; no test needed.
2412
2413 // See if we get an immediate positive hit. Happens roughly 83% of the
2414 // time. Test to see if the value loaded just previously from the subklass
2415 // is exactly the superklass.
2416 Node *cmp1 = _gvn.transform( new (C) CmpPNode( superklass, nkls ) );
2417 Node *bol1 = _gvn.transform( new (C) BoolNode( cmp1, BoolTest::eq ) );
2418 IfNode *iff1 = create_and_xform_if( control(), bol1, PROB_LIKELY(0.83f), COUNT_UNKNOWN );
2419 Node *iftrue1 = _gvn.transform( new (C) IfTrueNode ( iff1 ) );
2420 set_control( _gvn.transform( new (C) IfFalseNode( iff1 ) ) );
2421
2422 // Compile speed common case: Check for being deterministic right now. If
2423 // chk_off is a constant and not equal to cacheoff then we are NOT a
2424 // subklass. In this case we need exactly the 1 test above and we can
2425 // return those results immediately.
2426 if (!might_be_cache) {
2427 Node* not_subtype_ctrl = control();
2428 set_control(iftrue1); // We need exactly the 1 test above
2429 return not_subtype_ctrl;
2430 }
2431
2432 // Gather the various success & failures here
2433 RegionNode *r_ok_subtype = new (C) RegionNode(4);
2434 record_for_igvn(r_ok_subtype);
2435 RegionNode *r_not_subtype = new (C) RegionNode(3);
2436 record_for_igvn(r_not_subtype);
2437
2438 r_ok_subtype->init_req(1, iftrue1);
2439
2440 // Check for immediate negative hit. Happens roughly 11% of the time (which
2441 // is roughly 63% of the remaining cases). Test to see if the loaded
2442 // check-offset points into the subklass display list or the 1-element
2443 // cache. If it points to the display (and NOT the cache) and the display
2444 // missed then it's not a subtype.
2445 Node *cacheoff = _gvn.intcon(cacheoff_con);
2446 Node *cmp2 = _gvn.transform( new (C) CmpINode( chk_off, cacheoff ) );
2447 Node *bol2 = _gvn.transform( new (C) BoolNode( cmp2, BoolTest::ne ) );
2448 IfNode *iff2 = create_and_xform_if( control(), bol2, PROB_LIKELY(0.63f), COUNT_UNKNOWN );
2449 r_not_subtype->init_req(1, _gvn.transform( new (C) IfTrueNode (iff2) ) );
2450 set_control( _gvn.transform( new (C) IfFalseNode(iff2) ) );
2451
2452 // Check for self. Very rare to get here, but it is taken 1/3 the time.
2453 // No performance impact (too rare) but allows sharing of secondary arrays
2454 // which has some footprint reduction.
2455 Node *cmp3 = _gvn.transform( new (C) CmpPNode( subklass, superklass ) );
2456 Node *bol3 = _gvn.transform( new (C) BoolNode( cmp3, BoolTest::eq ) );
2457 IfNode *iff3 = create_and_xform_if( control(), bol3, PROB_LIKELY(0.36f), COUNT_UNKNOWN );
2458 r_ok_subtype->init_req(2, _gvn.transform( new (C) IfTrueNode ( iff3 ) ) );
2459 set_control( _gvn.transform( new (C) IfFalseNode( iff3 ) ) );
2460
2461 // -- Roads not taken here: --
2462 // We could also have chosen to perform the self-check at the beginning
2463 // of this code sequence, as the assembler does. This would not pay off
2464 // the same way, since the optimizer, unlike the assembler, can perform
2465 // static type analysis to fold away many successful self-checks.
2466 // Non-foldable self checks work better here in second position, because
2467 // the initial primary superclass check subsumes a self-check for most
2468 // types. An exception would be a secondary type like array-of-interface,
2469 // which does not appear in its own primary supertype display.
2470 // Finally, we could have chosen to move the self-check into the
2471 // PartialSubtypeCheckNode, and from there out-of-line in a platform
2472 // dependent manner. But it is worthwhile to have the check here,
2473 // where it can be perhaps be optimized. The cost in code space is
2474 // small (register compare, branch).
2475
2476 // Now do a linear scan of the secondary super-klass array. Again, no real
2477 // performance impact (too rare) but it's gotta be done.
2478 // Since the code is rarely used, there is no penalty for moving it
2479 // out of line, and it can only improve I-cache density.
2480 // The decision to inline or out-of-line this final check is platform
2481 // dependent, and is found in the AD file definition of PartialSubtypeCheck.
2482 Node* psc = _gvn.transform(
2483 new (C) PartialSubtypeCheckNode(control(), subklass, superklass) );
2484
2485 Node *cmp4 = _gvn.transform( new (C) CmpPNode( psc, null() ) );
2486 Node *bol4 = _gvn.transform( new (C) BoolNode( cmp4, BoolTest::ne ) );
2487 IfNode *iff4 = create_and_xform_if( control(), bol4, PROB_FAIR, COUNT_UNKNOWN );
2488 r_not_subtype->init_req(2, _gvn.transform( new (C) IfTrueNode (iff4) ) );
2489 r_ok_subtype ->init_req(3, _gvn.transform( new (C) IfFalseNode(iff4) ) );
2490
2491 // Return false path; set default control to true path.
2492 set_control( _gvn.transform(r_ok_subtype) );
2493 return _gvn.transform(r_not_subtype);
2494 }
2495
2496 //----------------------------static_subtype_check-----------------------------
2497 // Shortcut important common cases when superklass is exact:
2498 // (0) superklass is java.lang.Object (can occur in reflective code)
2499 // (1) subklass is already limited to a subtype of superklass => always ok
2500 // (2) subklass does not overlap with superklass => always fail
2501 // (3) superklass has NO subtypes and we can check with a simple compare.
2502 int GraphKit::static_subtype_check(ciKlass* superk, ciKlass* subk) {
2503 if (StressReflectiveCode) {
2504 return SSC_full_test; // Let caller generate the general case.
2505 }
2506
2507 if (superk == env()->Object_klass()) {
2508 return SSC_always_true; // (0) this test cannot fail
2509 }
2510
2511 ciType* superelem = superk;
2512 if (superelem->is_array_klass())
2513 superelem = superelem->as_array_klass()->base_element_type();
2514
2515 if (!subk->is_interface()) { // cannot trust static interface types yet
2516 if (subk->is_subtype_of(superk)) {
2517 return SSC_always_true; // (1) false path dead; no dynamic test needed
2518 }
2519 if (!(superelem->is_klass() && superelem->as_klass()->is_interface()) &&
2520 !superk->is_subtype_of(subk)) {
2521 return SSC_always_false;
2522 }
2523 }
2524
2525 // If casting to an instance klass, it must have no subtypes
2526 if (superk->is_interface()) {
2527 // Cannot trust interfaces yet.
2528 // %%% S.B. superk->nof_implementors() == 1
2529 } else if (superelem->is_instance_klass()) {
2530 ciInstanceKlass* ik = superelem->as_instance_klass();
2531 if (!ik->has_subklass() && !ik->is_interface()) {
2532 if (!ik->is_final()) {
2533 // Add a dependency if there is a chance of a later subclass.
2534 C->dependencies()->assert_leaf_type(ik);
2535 }
2536 return SSC_easy_test; // (3) caller can do a simple ptr comparison
2537 }
2538 } else {
2539 // A primitive array type has no subtypes.
2540 return SSC_easy_test; // (3) caller can do a simple ptr comparison
2541 }
2542
2543 return SSC_full_test;
2544 }
2545
2546 // Profile-driven exact type check:
2547 Node* GraphKit::type_check_receiver(Node* receiver, ciKlass* klass,
2548 float prob,
2549 Node* *casted_receiver) {
2550 const TypeKlassPtr* tklass = TypeKlassPtr::make(klass);
2551 Node* recv_klass = load_object_klass(receiver);
2552 Node* want_klass = makecon(tklass);
2553 Node* cmp = _gvn.transform( new(C) CmpPNode(recv_klass, want_klass) );
2554 Node* bol = _gvn.transform( new(C) BoolNode(cmp, BoolTest::eq) );
2555 IfNode* iff = create_and_xform_if(control(), bol, prob, COUNT_UNKNOWN);
2556 set_control( _gvn.transform( new(C) IfTrueNode (iff) ));
2557 Node* fail = _gvn.transform( new(C) IfFalseNode(iff) );
2558
2559 const TypeOopPtr* recv_xtype = tklass->as_instance_type();
2560 assert(recv_xtype->klass_is_exact(), "");
2561
2562 // Subsume downstream occurrences of receiver with a cast to
2563 // recv_xtype, since now we know what the type will be.
2564 Node* cast = new(C) CheckCastPPNode(control(), receiver, recv_xtype);
2565 (*casted_receiver) = _gvn.transform(cast);
2566 // (User must make the replace_in_map call.)
2567
2568 return fail;
2569 }
2570
2571
2572 //------------------------------seems_never_null-------------------------------
2573 // Use null_seen information if it is available from the profile.
2574 // If we see an unexpected null at a type check we record it and force a
2575 // recompile; the offending check will be recompiled to handle NULLs.
2576 // If we see several offending BCIs, then all checks in the
2577 // method will be recompiled.
2578 bool GraphKit::seems_never_null(Node* obj, ciProfileData* data) {
2579 if (UncommonNullCast // Cutout for this technique
2580 && obj != null() // And not the -Xcomp stupid case?
2581 && !too_many_traps(Deoptimization::Reason_null_check)
2582 ) {
2583 if (data == NULL)
2584 // Edge case: no mature data. Be optimistic here.
2585 return true;
2586 // If the profile has not seen a null, assume it won't happen.
2587 assert(java_bc() == Bytecodes::_checkcast ||
2588 java_bc() == Bytecodes::_instanceof ||
2589 java_bc() == Bytecodes::_aastore, "MDO must collect null_seen bit here");
2590 return !data->as_BitData()->null_seen();
2591 }
2592 return false;
2593 }
2594
2595 //------------------------maybe_cast_profiled_receiver-------------------------
2596 // If the profile has seen exactly one type, narrow to exactly that type.
2597 // Subsequent type checks will always fold up.
2598 Node* GraphKit::maybe_cast_profiled_receiver(Node* not_null_obj,
2599 ciProfileData* data,
2600 ciKlass* require_klass) {
2601 if (!UseTypeProfile || !TypeProfileCasts) return NULL;
2602 if (data == NULL) return NULL;
2603
2604 // Make sure we haven't already deoptimized from this tactic.
2605 if (too_many_traps(Deoptimization::Reason_class_check))
2606 return NULL;
2607
2608 // (No, this isn't a call, but it's enough like a virtual call
2609 // to use the same ciMethod accessor to get the profile info...)
2610 ciCallProfile profile = method()->call_profile_at_bci(bci());
2611 if (profile.count() >= 0 && // no cast failures here
2612 profile.has_receiver(0) &&
2613 profile.morphism() == 1) {
2614 ciKlass* exact_kls = profile.receiver(0);
2615 if (require_klass == NULL ||
2616 static_subtype_check(require_klass, exact_kls) == SSC_always_true) {
2617 // If we narrow the type to match what the type profile sees,
2618 // we can then remove the rest of the cast.
2619 // This is a win, even if the exact_kls is very specific,
2620 // because downstream operations, such as method calls,
2621 // will often benefit from the sharper type.
2622 Node* exact_obj = not_null_obj; // will get updated in place...
2623 Node* slow_ctl = type_check_receiver(exact_obj, exact_kls, 1.0,
2624 &exact_obj);
2625 { PreserveJVMState pjvms(this);
2626 set_control(slow_ctl);
2627 uncommon_trap(Deoptimization::Reason_class_check,
2628 Deoptimization::Action_maybe_recompile);
2629 }
2630 replace_in_map(not_null_obj, exact_obj);
2631 return exact_obj;
2632 }
2633 // assert(ssc == SSC_always_true)... except maybe the profile lied to us.
2634 }
2635
2636 return NULL;
2637 }
2638
2639
2640 //-------------------------------gen_instanceof--------------------------------
2641 // Generate an instance-of idiom. Used by both the instance-of bytecode
2642 // and the reflective instance-of call.
2643 Node* GraphKit::gen_instanceof(Node* obj, Node* superklass) {
2644 kill_dead_locals(); // Benefit all the uncommon traps
2645 assert( !stopped(), "dead parse path should be checked in callers" );
2646 assert(!TypePtr::NULL_PTR->higher_equal(_gvn.type(superklass)->is_klassptr()),
2647 "must check for not-null not-dead klass in callers");
2648
2649 // Make the merge point
2650 enum { _obj_path = 1, _fail_path, _null_path, PATH_LIMIT };
2651 RegionNode* region = new(C) RegionNode(PATH_LIMIT);
2652 Node* phi = new(C) PhiNode(region, TypeInt::BOOL);
2653 C->set_has_split_ifs(true); // Has chance for split-if optimization
2654
2655 ciProfileData* data = NULL;
2656 if (java_bc() == Bytecodes::_instanceof) { // Only for the bytecode
2657 data = method()->method_data()->bci_to_data(bci());
2658 }
2659 bool never_see_null = (ProfileDynamicTypes // aggressive use of profile
2660 && seems_never_null(obj, data));
2661
2662 // Null check; get casted pointer; set region slot 3
2663 Node* null_ctl = top();
2664 Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null);
2665
2666 // If not_null_obj is dead, only null-path is taken
2667 if (stopped()) { // Doing instance-of on a NULL?
2668 set_control(null_ctl);
2669 return intcon(0);
2670 }
2671 region->init_req(_null_path, null_ctl);
2672 phi ->init_req(_null_path, intcon(0)); // Set null path value
2673 if (null_ctl == top()) {
2674 // Do this eagerly, so that pattern matches like is_diamond_phi
2675 // will work even during parsing.
2676 assert(_null_path == PATH_LIMIT-1, "delete last");
2677 region->del_req(_null_path);
2678 phi ->del_req(_null_path);
2679 }
2680
2681 if (ProfileDynamicTypes && data != NULL) {
2682 Node* cast_obj = maybe_cast_profiled_receiver(not_null_obj, data, NULL);
2683 if (stopped()) { // Profile disagrees with this path.
2684 set_control(null_ctl); // Null is the only remaining possibility.
2685 return intcon(0);
2686 }
2687 if (cast_obj != NULL)
2688 not_null_obj = cast_obj;
2689 }
2690
2691 // Load the object's klass
2692 Node* obj_klass = load_object_klass(not_null_obj);
2693
2694 // Generate the subtype check
2695 Node* not_subtype_ctrl = gen_subtype_check(obj_klass, superklass);
2696
2697 // Plug in the success path to the general merge in slot 1.
2698 region->init_req(_obj_path, control());
2699 phi ->init_req(_obj_path, intcon(1));
2700
2701 // Plug in the failing path to the general merge in slot 2.
2702 region->init_req(_fail_path, not_subtype_ctrl);
2703 phi ->init_req(_fail_path, intcon(0));
2704
2705 // Return final merged results
2706 set_control( _gvn.transform(region) );
2707 record_for_igvn(region);
2708 return _gvn.transform(phi);
2709 }
2710
2711 //-------------------------------gen_checkcast---------------------------------
2712 // Generate a checkcast idiom. Used by both the checkcast bytecode and the
2713 // array store bytecode. Stack must be as-if BEFORE doing the bytecode so the
2714 // uncommon-trap paths work. Adjust stack after this call.
2715 // If failure_control is supplied and not null, it is filled in with
2716 // the control edge for the cast failure. Otherwise, an appropriate
2717 // uncommon trap or exception is thrown.
2718 Node* GraphKit::gen_checkcast(Node *obj, Node* superklass,
2719 Node* *failure_control) {
2720 kill_dead_locals(); // Benefit all the uncommon traps
2721 const TypeKlassPtr *tk = _gvn.type(superklass)->is_klassptr();
2722 const Type *toop = TypeOopPtr::make_from_klass(tk->klass());
2723
2724 // Fast cutout: Check the case that the cast is vacuously true.
2725 // This detects the common cases where the test will short-circuit
2726 // away completely. We do this before we perform the null check,
2727 // because if the test is going to turn into zero code, we don't
2728 // want a residual null check left around. (Causes a slowdown,
2729 // for example, in some objArray manipulations, such as a[i]=a[j].)
2730 if (tk->singleton()) {
2731 const TypeOopPtr* objtp = _gvn.type(obj)->isa_oopptr();
2732 if (objtp != NULL && objtp->klass() != NULL) {
2733 switch (static_subtype_check(tk->klass(), objtp->klass())) {
2734 case SSC_always_true:
2735 return obj;
2736 case SSC_always_false:
2737 // It needs a null check because a null will *pass* the cast check.
2738 // A non-null value will always produce an exception.
2739 return null_assert(obj);
2740 }
2741 }
2742 }
2743
2744 ciProfileData* data = NULL;
2745 if (failure_control == NULL) { // use MDO in regular case only
2746 assert(java_bc() == Bytecodes::_aastore ||
2747 java_bc() == Bytecodes::_checkcast,
2748 "interpreter profiles type checks only for these BCs");
2749 data = method()->method_data()->bci_to_data(bci());
2750 }
2751
2752 // Make the merge point
2753 enum { _obj_path = 1, _null_path, PATH_LIMIT };
2754 RegionNode* region = new (C) RegionNode(PATH_LIMIT);
2755 Node* phi = new (C) PhiNode(region, toop);
2756 C->set_has_split_ifs(true); // Has chance for split-if optimization
2757
2758 // Use null-cast information if it is available
2759 bool never_see_null = ((failure_control == NULL) // regular case only
2760 && seems_never_null(obj, data));
2761
2762 // Null check; get casted pointer; set region slot 3
2763 Node* null_ctl = top();
2764 Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null);
2765
2766 // If not_null_obj is dead, only null-path is taken
2767 if (stopped()) { // Doing instance-of on a NULL?
2768 set_control(null_ctl);
2769 return null();
2770 }
2771 region->init_req(_null_path, null_ctl);
2772 phi ->init_req(_null_path, null()); // Set null path value
2773 if (null_ctl == top()) {
2774 // Do this eagerly, so that pattern matches like is_diamond_phi
2775 // will work even during parsing.
2776 assert(_null_path == PATH_LIMIT-1, "delete last");
2777 region->del_req(_null_path);
2778 phi ->del_req(_null_path);
2779 }
2780
2781 Node* cast_obj = NULL;
2782 if (tk->klass_is_exact()) {
2783 // The following optimization tries to statically cast the speculative type of the object
2784 // (for example obtained during profiling) to the type of the superklass and then do a
2785 // dynamic check that the type of the object is what we expect. To work correctly
2786 // for checkcast and aastore the type of superklass should be exact.
2787 if (data != NULL &&
2788 // Counter has never been decremented (due to cast failure).
2789 // ...This is a reasonable thing to expect. It is true of
2790 // all casts inserted by javac to implement generic types.
2791 data->as_CounterData()->count() >= 0) {
2792 cast_obj = maybe_cast_profiled_receiver(not_null_obj, data, tk->klass());
2793 if (cast_obj != NULL) {
2794 if (failure_control != NULL) // failure is now impossible
2795 (*failure_control) = top();
2796 // adjust the type of the phi to the exact klass:
2797 phi->raise_bottom_type(_gvn.type(cast_obj)->meet(TypePtr::NULL_PTR));
2798 }
2799 }
2800 }
2801
2802 if (cast_obj == NULL) {
2803 // Load the object's klass
2804 Node* obj_klass = load_object_klass(not_null_obj);
2805
2806 // Generate the subtype check
2807 Node* not_subtype_ctrl = gen_subtype_check( obj_klass, superklass );
2808
2809 // Plug in success path into the merge
2810 cast_obj = _gvn.transform(new (C) CheckCastPPNode(control(),
2811 not_null_obj, toop));
2812 // Failure path ends in uncommon trap (or may be dead - failure impossible)
2813 if (failure_control == NULL) {
2814 if (not_subtype_ctrl != top()) { // If failure is possible
2815 PreserveJVMState pjvms(this);
2816 set_control(not_subtype_ctrl);
2817 builtin_throw(Deoptimization::Reason_class_check, obj_klass);
2818 }
2819 } else {
2820 (*failure_control) = not_subtype_ctrl;
2821 }
2822 }
2823
2824 region->init_req(_obj_path, control());
2825 phi ->init_req(_obj_path, cast_obj);
2826
2827 // A merge of NULL or Casted-NotNull obj
2828 Node* res = _gvn.transform(phi);
2829
2830 // Note I do NOT always 'replace_in_map(obj,result)' here.
2831 // if( tk->klass()->can_be_primary_super() )
2832 // This means that if I successfully store an Object into an array-of-String
2833 // I 'forget' that the Object is really now known to be a String. I have to
2834 // do this because we don't have true union types for interfaces - if I store
2835 // a Baz into an array-of-Interface and then tell the optimizer it's an
2836 // Interface, I forget that it's also a Baz and cannot do Baz-like field
2837 // references to it. FIX THIS WHEN UNION TYPES APPEAR!
2838 // replace_in_map( obj, res );
2839
2840 // Return final merged results
2841 set_control( _gvn.transform(region) );
2842 record_for_igvn(region);
2843 return res;
2844 }
2845
2846 //------------------------------next_monitor-----------------------------------
2847 // What number should be given to the next monitor?
2848 int GraphKit::next_monitor() {
2849 int current = jvms()->monitor_depth()* C->sync_stack_slots();
2850 int next = current + C->sync_stack_slots();
2851 // Keep the toplevel high water mark current:
2852 if (C->fixed_slots() < next) C->set_fixed_slots(next);
2853 return current;
2854 }
2855
2856 //------------------------------insert_mem_bar---------------------------------
2857 // Memory barrier to avoid floating things around
2858 // The membar serves as a pinch point between both control and all memory slices.
2859 Node* GraphKit::insert_mem_bar(int opcode, Node* precedent) {
2860 MemBarNode* mb = MemBarNode::make(C, opcode, Compile::AliasIdxBot, precedent);
2861 mb->init_req(TypeFunc::Control, control());
2862 mb->init_req(TypeFunc::Memory, reset_memory());
2863 Node* membar = _gvn.transform(mb);
2864 set_control(_gvn.transform(new (C) ProjNode(membar, TypeFunc::Control)));
2865 set_all_memory_call(membar);
2866 return membar;
2867 }
2868
2869 //-------------------------insert_mem_bar_volatile----------------------------
2870 // Memory barrier to avoid floating things around
2871 // The membar serves as a pinch point between both control and memory(alias_idx).
2872 // If you want to make a pinch point on all memory slices, do not use this
2873 // function (even with AliasIdxBot); use insert_mem_bar() instead.
2874 Node* GraphKit::insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent) {
2875 // When Parse::do_put_xxx updates a volatile field, it appends a series
2876 // of MemBarVolatile nodes, one for *each* volatile field alias category.
2877 // The first membar is on the same memory slice as the field store opcode.
2878 // This forces the membar to follow the store. (Bug 6500685 broke this.)
2879 // All the other membars (for other volatile slices, including AliasIdxBot,
2880 // which stands for all unknown volatile slices) are control-dependent
2881 // on the first membar. This prevents later volatile loads or stores
2882 // from sliding up past the just-emitted store.
2883
2884 MemBarNode* mb = MemBarNode::make(C, opcode, alias_idx, precedent);
2885 mb->set_req(TypeFunc::Control,control());
2886 if (alias_idx == Compile::AliasIdxBot) {
2887 mb->set_req(TypeFunc::Memory, merged_memory()->base_memory());
2888 } else {
2889 assert(!(opcode == Op_Initialize && alias_idx != Compile::AliasIdxRaw), "fix caller");
2890 mb->set_req(TypeFunc::Memory, memory(alias_idx));
2891 }
2892 Node* membar = _gvn.transform(mb);
2893 set_control(_gvn.transform(new (C) ProjNode(membar, TypeFunc::Control)));
2894 if (alias_idx == Compile::AliasIdxBot) {
2895 merged_memory()->set_base_memory(_gvn.transform(new (C) ProjNode(membar, TypeFunc::Memory)));
2896 } else {
2897 set_memory(_gvn.transform(new (C) ProjNode(membar, TypeFunc::Memory)),alias_idx);
2898 }
2899 return membar;
2900 }
2901
2902 //------------------------------shared_lock------------------------------------
2903 // Emit locking code.
2904 FastLockNode* GraphKit::shared_lock(Node* obj) {
2905 // bci is either a monitorenter bc or InvocationEntryBci
2906 // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
2907 assert(SynchronizationEntryBCI == InvocationEntryBci, "");
2908
2909 if( !GenerateSynchronizationCode )
2910 return NULL; // Not locking things?
2911 if (stopped()) // Dead monitor?
2912 return NULL;
2913
2914 assert(dead_locals_are_killed(), "should kill locals before sync. point");
2915
2916 // Box the stack location
2917 Node* box = _gvn.transform(new (C) BoxLockNode(next_monitor()));
2918 Node* mem = reset_memory();
2919
2920 FastLockNode * flock = _gvn.transform(new (C) FastLockNode(0, obj, box) )->as_FastLock();
2921 if (PrintPreciseBiasedLockingStatistics) {
2922 // Create the counters for this fast lock.
2923 flock->create_lock_counter(sync_jvms()); // sync_jvms used to get current bci
2924 }
2925 // Add monitor to debug info for the slow path. If we block inside the
2926 // slow path and de-opt, we need the monitor hanging around
2927 map()->push_monitor( flock );
2928
2929 const TypeFunc *tf = LockNode::lock_type();
2930 LockNode *lock = new (C) LockNode(C, tf);
2931
2932 lock->init_req( TypeFunc::Control, control() );
2933 lock->init_req( TypeFunc::Memory , mem );
2934 lock->init_req( TypeFunc::I_O , top() ) ; // does no i/o
2935 lock->init_req( TypeFunc::FramePtr, frameptr() );
2936 lock->init_req( TypeFunc::ReturnAdr, top() );
2937
2938 lock->init_req(TypeFunc::Parms + 0, obj);
2939 lock->init_req(TypeFunc::Parms + 1, box);
2940 lock->init_req(TypeFunc::Parms + 2, flock);
2941 add_safepoint_edges(lock);
2942
2943 lock = _gvn.transform( lock )->as_Lock();
2944
2945 // lock has no side-effects, sets few values
2946 set_predefined_output_for_runtime_call(lock, mem, TypeRawPtr::BOTTOM);
2947
2948 insert_mem_bar(Op_MemBarAcquireLock);
2949
2950 // Add this to the worklist so that the lock can be eliminated
2951 record_for_igvn(lock);
2952
2953 #ifndef PRODUCT
2954 if (PrintLockStatistics) {
2955 // Update the counter for this lock. Don't bother using an atomic
2956 // operation since we don't require absolute accuracy.
2957 lock->create_lock_counter(map()->jvms());
2958 increment_counter(lock->counter()->addr());
2959 }
2960 #endif
2961
2962 return flock;
2963 }
2964
2965
2966 //------------------------------shared_unlock----------------------------------
2967 // Emit unlocking code.
2968 void GraphKit::shared_unlock(Node* box, Node* obj) {
2969 // bci is either a monitorenter bc or InvocationEntryBci
2970 // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
2971 assert(SynchronizationEntryBCI == InvocationEntryBci, "");
2972
2973 if( !GenerateSynchronizationCode )
2974 return;
2975 if (stopped()) { // Dead monitor?
2976 map()->pop_monitor(); // Kill monitor from debug info
2977 return;
2978 }
2979
2980 // Memory barrier to avoid floating things down past the locked region
2981 insert_mem_bar(Op_MemBarReleaseLock);
2982
2983 const TypeFunc *tf = OptoRuntime::complete_monitor_exit_Type();
2984 UnlockNode *unlock = new (C) UnlockNode(C, tf);
2985 uint raw_idx = Compile::AliasIdxRaw;
2986 unlock->init_req( TypeFunc::Control, control() );
2987 unlock->init_req( TypeFunc::Memory , memory(raw_idx) );
2988 unlock->init_req( TypeFunc::I_O , top() ) ; // does no i/o
2989 unlock->init_req( TypeFunc::FramePtr, frameptr() );
2990 unlock->init_req( TypeFunc::ReturnAdr, top() );
2991
2992 unlock->init_req(TypeFunc::Parms + 0, obj);
2993 unlock->init_req(TypeFunc::Parms + 1, box);
2994 unlock = _gvn.transform(unlock)->as_Unlock();
2995
2996 Node* mem = reset_memory();
2997
2998 // unlock has no side-effects, sets few values
2999 set_predefined_output_for_runtime_call(unlock, mem, TypeRawPtr::BOTTOM);
3000
3001 // Kill monitor from debug info
3002 map()->pop_monitor( );
3003 }
3004
3005 //-------------------------------get_layout_helper-----------------------------
3006 // If the given klass is a constant or known to be an array,
3007 // fetch the constant layout helper value into constant_value
3008 // and return (Node*)NULL. Otherwise, load the non-constant
3009 // layout helper value, and return the node which represents it.
3010 // This two-faced routine is useful because allocation sites
3011 // almost always feature constant types.
3012 Node* GraphKit::get_layout_helper(Node* klass_node, jint& constant_value) {
3013 const TypeKlassPtr* inst_klass = _gvn.type(klass_node)->isa_klassptr();
3014 if (!StressReflectiveCode && inst_klass != NULL) {
3015 ciKlass* klass = inst_klass->klass();
3016 bool xklass = inst_klass->klass_is_exact();
3017 if (xklass || klass->is_array_klass()) {
3018 jint lhelper = klass->layout_helper();
3019 if (lhelper != Klass::_lh_neutral_value) {
3020 constant_value = lhelper;
3021 return (Node*) NULL;
3022 }
3023 }
3024 }
3025 constant_value = Klass::_lh_neutral_value; // put in a known value
3026 Node* lhp = basic_plus_adr(klass_node, klass_node, in_bytes(Klass::layout_helper_offset()));
3027 return make_load(NULL, lhp, TypeInt::INT, T_INT);
3028 }
3029
3030 // We just put in an allocate/initialize with a big raw-memory effect.
3031 // Hook selected additional alias categories on the initialization.
3032 static void hook_memory_on_init(GraphKit& kit, int alias_idx,
3033 MergeMemNode* init_in_merge,
3034 Node* init_out_raw) {
3035 DEBUG_ONLY(Node* init_in_raw = init_in_merge->base_memory());
3036 assert(init_in_merge->memory_at(alias_idx) == init_in_raw, "");
3037
3038 Node* prevmem = kit.memory(alias_idx);
3039 init_in_merge->set_memory_at(alias_idx, prevmem);
3040 kit.set_memory(init_out_raw, alias_idx);
3041 }
3042
3043 //---------------------------set_output_for_allocation-------------------------
3044 Node* GraphKit::set_output_for_allocation(AllocateNode* alloc,
3045 const TypeOopPtr* oop_type) {
3046 int rawidx = Compile::AliasIdxRaw;
3047 alloc->set_req( TypeFunc::FramePtr, frameptr() );
3048 add_safepoint_edges(alloc);
3049 Node* allocx = _gvn.transform(alloc);
3050 set_control( _gvn.transform(new (C) ProjNode(allocx, TypeFunc::Control) ) );
3051 // create memory projection for i_o
3052 set_memory ( _gvn.transform( new (C) ProjNode(allocx, TypeFunc::Memory, true) ), rawidx );
3053 make_slow_call_ex(allocx, env()->Throwable_klass(), true);
3054
3055 // create a memory projection as for the normal control path
3056 Node* malloc = _gvn.transform(new (C) ProjNode(allocx, TypeFunc::Memory));
3057 set_memory(malloc, rawidx);
3058
3059 // a normal slow-call doesn't change i_o, but an allocation does
3060 // we create a separate i_o projection for the normal control path
3061 set_i_o(_gvn.transform( new (C) ProjNode(allocx, TypeFunc::I_O, false) ) );
3062 Node* rawoop = _gvn.transform( new (C) ProjNode(allocx, TypeFunc::Parms) );
3063
3064 // put in an initialization barrier
3065 InitializeNode* init = insert_mem_bar_volatile(Op_Initialize, rawidx,
3066 rawoop)->as_Initialize();
3067 assert(alloc->initialization() == init, "2-way macro link must work");
3068 assert(init ->allocation() == alloc, "2-way macro link must work");
3069 {
3070 // Extract memory strands which may participate in the new object's
3071 // initialization, and source them from the new InitializeNode.
3072 // This will allow us to observe initializations when they occur,
3073 // and link them properly (as a group) to the InitializeNode.
3074 assert(init->in(InitializeNode::Memory) == malloc, "");
3075 MergeMemNode* minit_in = MergeMemNode::make(C, malloc);
3076 init->set_req(InitializeNode::Memory, minit_in);
3077 record_for_igvn(minit_in); // fold it up later, if possible
3078 Node* minit_out = memory(rawidx);
3079 assert(minit_out->is_Proj() && minit_out->in(0) == init, "");
3080 if (oop_type->isa_aryptr()) {
3081 const TypePtr* telemref = oop_type->add_offset(Type::OffsetBot);
3082 int elemidx = C->get_alias_index(telemref);
3083 hook_memory_on_init(*this, elemidx, minit_in, minit_out);
3084 } else if (oop_type->isa_instptr()) {
3085 ciInstanceKlass* ik = oop_type->klass()->as_instance_klass();
3086 for (int i = 0, len = ik->nof_nonstatic_fields(); i < len; i++) {
3087 ciField* field = ik->nonstatic_field_at(i);
3088 if (field->offset() >= TrackedInitializationLimit * HeapWordSize)
3089 continue; // do not bother to track really large numbers of fields
3090 // Find (or create) the alias category for this field:
3091 int fieldidx = C->alias_type(field)->index();
3092 hook_memory_on_init(*this, fieldidx, minit_in, minit_out);
3093 }
3094 }
3095 }
3096
3097 // Cast raw oop to the real thing...
3098 Node* javaoop = new (C) CheckCastPPNode(control(), rawoop, oop_type);
3099 javaoop = _gvn.transform(javaoop);
3100 C->set_recent_alloc(control(), javaoop);
3101 assert(just_allocated_object(control()) == javaoop, "just allocated");
3102
3103 #ifdef ASSERT
3104 { // Verify that the AllocateNode::Ideal_allocation recognizers work:
3105 assert(AllocateNode::Ideal_allocation(rawoop, &_gvn) == alloc,
3106 "Ideal_allocation works");
3107 assert(AllocateNode::Ideal_allocation(javaoop, &_gvn) == alloc,
3108 "Ideal_allocation works");
3109 if (alloc->is_AllocateArray()) {
3110 assert(AllocateArrayNode::Ideal_array_allocation(rawoop, &_gvn) == alloc->as_AllocateArray(),
3111 "Ideal_allocation works");
3112 assert(AllocateArrayNode::Ideal_array_allocation(javaoop, &_gvn) == alloc->as_AllocateArray(),
3113 "Ideal_allocation works");
3114 } else {
3115 assert(alloc->in(AllocateNode::ALength)->is_top(), "no length, please");
3116 }
3117 }
3118 #endif //ASSERT
3119
3120 return javaoop;
3121 }
3122
3123 //---------------------------new_instance--------------------------------------
3124 // This routine takes a klass_node which may be constant (for a static type)
3125 // or may be non-constant (for reflective code). It will work equally well
3126 // for either, and the graph will fold nicely if the optimizer later reduces
3127 // the type to a constant.
3128 // The optional arguments are for specialized use by intrinsics:
3129 // - If 'extra_slow_test' if not null is an extra condition for the slow-path.
3130 // - If 'return_size_val', report the the total object size to the caller.
3131 Node* GraphKit::new_instance(Node* klass_node,
3132 Node* extra_slow_test,
3133 Node* *return_size_val) {
3134 // Compute size in doublewords
3135 // The size is always an integral number of doublewords, represented
3136 // as a positive bytewise size stored in the klass's layout_helper.
3137 // The layout_helper also encodes (in a low bit) the need for a slow path.
3138 jint layout_con = Klass::_lh_neutral_value;
3139 Node* layout_val = get_layout_helper(klass_node, layout_con);
3140 int layout_is_con = (layout_val == NULL);
3141
3142 if (extra_slow_test == NULL) extra_slow_test = intcon(0);
3143 // Generate the initial go-slow test. It's either ALWAYS (return a
3144 // Node for 1) or NEVER (return a NULL) or perhaps (in the reflective
3145 // case) a computed value derived from the layout_helper.
3146 Node* initial_slow_test = NULL;
3147 if (layout_is_con) {
3148 assert(!StressReflectiveCode, "stress mode does not use these paths");
3149 bool must_go_slow = Klass::layout_helper_needs_slow_path(layout_con);
3150 initial_slow_test = must_go_slow? intcon(1): extra_slow_test;
3151
3152 } else { // reflective case
3153 // This reflective path is used by Unsafe.allocateInstance.
3154 // (It may be stress-tested by specifying StressReflectiveCode.)
3155 // Basically, we want to get into the VM is there's an illegal argument.
3156 Node* bit = intcon(Klass::_lh_instance_slow_path_bit);
3157 initial_slow_test = _gvn.transform( new (C) AndINode(layout_val, bit) );
3158 if (extra_slow_test != intcon(0)) {
3159 initial_slow_test = _gvn.transform( new (C) OrINode(initial_slow_test, extra_slow_test) );
3160 }
3161 // (Macro-expander will further convert this to a Bool, if necessary.)
3162 }
3163
3164 // Find the size in bytes. This is easy; it's the layout_helper.
3165 // The size value must be valid even if the slow path is taken.
3166 Node* size = NULL;
3167 if (layout_is_con) {
3168 size = MakeConX(Klass::layout_helper_size_in_bytes(layout_con));
3169 } else { // reflective case
3170 // This reflective path is used by clone and Unsafe.allocateInstance.
3171 size = ConvI2X(layout_val);
3172
3173 // Clear the low bits to extract layout_helper_size_in_bytes:
3174 assert((int)Klass::_lh_instance_slow_path_bit < BytesPerLong, "clear bit");
3175 Node* mask = MakeConX(~ (intptr_t)right_n_bits(LogBytesPerLong));
3176 size = _gvn.transform( new (C) AndXNode(size, mask) );
3177 }
3178 if (return_size_val != NULL) {
3179 (*return_size_val) = size;
3180 }
3181
3182 // This is a precise notnull oop of the klass.
3183 // (Actually, it need not be precise if this is a reflective allocation.)
3184 // It's what we cast the result to.
3185 const TypeKlassPtr* tklass = _gvn.type(klass_node)->isa_klassptr();
3186 if (!tklass) tklass = TypeKlassPtr::OBJECT;
3187 const TypeOopPtr* oop_type = tklass->as_instance_type();
3188
3189 // Now generate allocation code
3190
3191 // The entire memory state is needed for slow path of the allocation
3192 // since GC and deoptimization can happened.
3193 Node *mem = reset_memory();
3194 set_all_memory(mem); // Create new memory state
3195
3196 AllocateNode* alloc
3197 = new (C) AllocateNode(C, AllocateNode::alloc_type(),
3198 control(), mem, i_o(),
3199 size, klass_node,
3200 initial_slow_test);
3201
3202 return set_output_for_allocation(alloc, oop_type);
3203 }
3204
3205 //-------------------------------new_array-------------------------------------
3206 // helper for both newarray and anewarray
3207 // The 'length' parameter is (obviously) the length of the array.
3208 // See comments on new_instance for the meaning of the other arguments.
3209 Node* GraphKit::new_array(Node* klass_node, // array klass (maybe variable)
3210 Node* length, // number of array elements
3211 int nargs, // number of arguments to push back for uncommon trap
3212 Node* *return_size_val) {
3213 jint layout_con = Klass::_lh_neutral_value;
3214 Node* layout_val = get_layout_helper(klass_node, layout_con);
3215 int layout_is_con = (layout_val == NULL);
3216
3217 if (!layout_is_con && !StressReflectiveCode &&
3218 !too_many_traps(Deoptimization::Reason_class_check)) {
3219 // This is a reflective array creation site.
3220 // Optimistically assume that it is a subtype of Object[],
3221 // so that we can fold up all the address arithmetic.
3222 layout_con = Klass::array_layout_helper(T_OBJECT);
3223 Node* cmp_lh = _gvn.transform( new(C) CmpINode(layout_val, intcon(layout_con)) );
3224 Node* bol_lh = _gvn.transform( new(C) BoolNode(cmp_lh, BoolTest::eq) );
3225 { BuildCutout unless(this, bol_lh, PROB_MAX);
3226 inc_sp(nargs);
3227 uncommon_trap(Deoptimization::Reason_class_check,
3228 Deoptimization::Action_maybe_recompile);
3229 }
3230 layout_val = NULL;
3231 layout_is_con = true;
3232 }
3233
3234 // Generate the initial go-slow test. Make sure we do not overflow
3235 // if length is huge (near 2Gig) or negative! We do not need
3236 // exact double-words here, just a close approximation of needed
3237 // double-words. We can't add any offset or rounding bits, lest we
3238 // take a size -1 of bytes and make it positive. Use an unsigned
3239 // compare, so negative sizes look hugely positive.
3240 int fast_size_limit = FastAllocateSizeLimit;
3241 if (layout_is_con) {
3242 assert(!StressReflectiveCode, "stress mode does not use these paths");
3243 // Increase the size limit if we have exact knowledge of array type.
3244 int log2_esize = Klass::layout_helper_log2_element_size(layout_con);
3245 fast_size_limit <<= (LogBytesPerLong - log2_esize);
3246 }
3247
3248 Node* initial_slow_cmp = _gvn.transform( new (C) CmpUNode( length, intcon( fast_size_limit ) ) );
3249 Node* initial_slow_test = _gvn.transform( new (C) BoolNode( initial_slow_cmp, BoolTest::gt ) );
3250 if (initial_slow_test->is_Bool()) {
3251 // Hide it behind a CMoveI, or else PhaseIdealLoop::split_up will get sick.
3252 initial_slow_test = initial_slow_test->as_Bool()->as_int_value(&_gvn);
3253 }
3254
3255 // --- Size Computation ---
3256 // array_size = round_to_heap(array_header + (length << elem_shift));
3257 // where round_to_heap(x) == round_to(x, MinObjAlignmentInBytes)
3258 // and round_to(x, y) == ((x + y-1) & ~(y-1))
3259 // The rounding mask is strength-reduced, if possible.
3260 int round_mask = MinObjAlignmentInBytes - 1;
3261 Node* header_size = NULL;
3262 int header_size_min = arrayOopDesc::base_offset_in_bytes(T_BYTE);
3263 // (T_BYTE has the weakest alignment and size restrictions...)
3264 if (layout_is_con) {
3265 int hsize = Klass::layout_helper_header_size(layout_con);
3266 int eshift = Klass::layout_helper_log2_element_size(layout_con);
3267 BasicType etype = Klass::layout_helper_element_type(layout_con);
3268 if ((round_mask & ~right_n_bits(eshift)) == 0)
3269 round_mask = 0; // strength-reduce it if it goes away completely
3270 assert((hsize & right_n_bits(eshift)) == 0, "hsize is pre-rounded");
3271 assert(header_size_min <= hsize, "generic minimum is smallest");
3272 header_size_min = hsize;
3273 header_size = intcon(hsize + round_mask);
3274 } else {
3275 Node* hss = intcon(Klass::_lh_header_size_shift);
3276 Node* hsm = intcon(Klass::_lh_header_size_mask);
3277 Node* hsize = _gvn.transform( new(C) URShiftINode(layout_val, hss) );
3278 hsize = _gvn.transform( new(C) AndINode(hsize, hsm) );
3279 Node* mask = intcon(round_mask);
3280 header_size = _gvn.transform( new(C) AddINode(hsize, mask) );
3281 }
3282
3283 Node* elem_shift = NULL;
3284 if (layout_is_con) {
3285 int eshift = Klass::layout_helper_log2_element_size(layout_con);
3286 if (eshift != 0)
3287 elem_shift = intcon(eshift);
3288 } else {
3289 // There is no need to mask or shift this value.
3290 // The semantics of LShiftINode include an implicit mask to 0x1F.
3291 assert(Klass::_lh_log2_element_size_shift == 0, "use shift in place");
3292 elem_shift = layout_val;
3293 }
3294
3295 // Transition to native address size for all offset calculations:
3296 Node* lengthx = ConvI2X(length);
3297 Node* headerx = ConvI2X(header_size);
3298 #ifdef _LP64
3299 { const TypeLong* tllen = _gvn.find_long_type(lengthx);
3300 if (tllen != NULL && tllen->_lo < 0) {
3301 // Add a manual constraint to a positive range. Cf. array_element_address.
3302 jlong size_max = arrayOopDesc::max_array_length(T_BYTE);
3303 if (size_max > tllen->_hi) size_max = tllen->_hi;
3304 const TypeLong* tlcon = TypeLong::make(CONST64(0), size_max, Type::WidenMin);
3305 lengthx = _gvn.transform( new (C) ConvI2LNode(length, tlcon));
3306 }
3307 }
3308 #endif
3309
3310 // Combine header size (plus rounding) and body size. Then round down.
3311 // This computation cannot overflow, because it is used only in two
3312 // places, one where the length is sharply limited, and the other
3313 // after a successful allocation.
3314 Node* abody = lengthx;
3315 if (elem_shift != NULL)
3316 abody = _gvn.transform( new(C) LShiftXNode(lengthx, elem_shift) );
3317 Node* size = _gvn.transform( new(C) AddXNode(headerx, abody) );
3318 if (round_mask != 0) {
3319 Node* mask = MakeConX(~round_mask);
3320 size = _gvn.transform( new(C) AndXNode(size, mask) );
3321 }
3322 // else if round_mask == 0, the size computation is self-rounding
3323
3324 if (return_size_val != NULL) {
3325 // This is the size
3326 (*return_size_val) = size;
3327 }
3328
3329 // Now generate allocation code
3330
3331 // The entire memory state is needed for slow path of the allocation
3332 // since GC and deoptimization can happened.
3333 Node *mem = reset_memory();
3334 set_all_memory(mem); // Create new memory state
3335
3336 // Create the AllocateArrayNode and its result projections
3337 AllocateArrayNode* alloc
3338 = new (C) AllocateArrayNode(C, AllocateArrayNode::alloc_type(),
3339 control(), mem, i_o(),
3340 size, klass_node,
3341 initial_slow_test,
3342 length);
3343
3344 // Cast to correct type. Note that the klass_node may be constant or not,
3345 // and in the latter case the actual array type will be inexact also.
3346 // (This happens via a non-constant argument to inline_native_newArray.)
3347 // In any case, the value of klass_node provides the desired array type.
3348 const TypeInt* length_type = _gvn.find_int_type(length);
3349 const TypeOopPtr* ary_type = _gvn.type(klass_node)->is_klassptr()->as_instance_type();
3350 if (ary_type->isa_aryptr() && length_type != NULL) {
3351 // Try to get a better type than POS for the size
3352 ary_type = ary_type->is_aryptr()->cast_to_size(length_type);
3353 }
3354
3355 Node* javaoop = set_output_for_allocation(alloc, ary_type);
3356
3357 // Cast length on remaining path to be as narrow as possible
3358 if (map()->find_edge(length) >= 0) {
3359 Node* ccast = alloc->make_ideal_length(ary_type, &_gvn);
3360 if (ccast != length) {
3361 _gvn.set_type_bottom(ccast);
3362 record_for_igvn(ccast);
3363 replace_in_map(length, ccast);
3364 }
3365 }
3366
3367 return javaoop;
3368 }
3369
3370 // The following "Ideal_foo" functions are placed here because they recognize
3371 // the graph shapes created by the functions immediately above.
3372
3373 //---------------------------Ideal_allocation----------------------------------
3374 // Given an oop pointer or raw pointer, see if it feeds from an AllocateNode.
3375 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase) {
3376 if (ptr == NULL) { // reduce dumb test in callers
3377 return NULL;
3378 }
3379 if (ptr->is_CheckCastPP()) { // strip a raw-to-oop cast
3380 ptr = ptr->in(1);
3381 if (ptr == NULL) return NULL;
3382 }
3383 if (ptr->is_Proj()) {
3384 Node* allo = ptr->in(0);
3385 if (allo != NULL && allo->is_Allocate()) {
3386 return allo->as_Allocate();
3387 }
3388 }
3389 // Report failure to match.
3390 return NULL;
3391 }
3392
3393 // Fancy version which also strips off an offset (and reports it to caller).
3394 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase,
3395 intptr_t& offset) {
3396 Node* base = AddPNode::Ideal_base_and_offset(ptr, phase, offset);
3397 if (base == NULL) return NULL;
3398 return Ideal_allocation(base, phase);
3399 }
3400
3401 // Trace Initialize <- Proj[Parm] <- Allocate
3402 AllocateNode* InitializeNode::allocation() {
3403 Node* rawoop = in(InitializeNode::RawAddress);
3404 if (rawoop->is_Proj()) {
3405 Node* alloc = rawoop->in(0);
3406 if (alloc->is_Allocate()) {
3407 return alloc->as_Allocate();
3408 }
3409 }
3410 return NULL;
3411 }
3412
3413 // Trace Allocate -> Proj[Parm] -> Initialize
3414 InitializeNode* AllocateNode::initialization() {
3415 ProjNode* rawoop = proj_out(AllocateNode::RawAddress);
3416 if (rawoop == NULL) return NULL;
3417 for (DUIterator_Fast imax, i = rawoop->fast_outs(imax); i < imax; i++) {
3418 Node* init = rawoop->fast_out(i);
3419 if (init->is_Initialize()) {
3420 assert(init->as_Initialize()->allocation() == this, "2-way link");
3421 return init->as_Initialize();
3422 }
3423 }
3424 return NULL;
3425 }
3426
3427 // Trace Allocate -> Proj[Parm] -> MemBarStoreStore
3428 MemBarStoreStoreNode* AllocateNode::storestore() {
3429 ProjNode* rawoop = proj_out(AllocateNode::RawAddress);
3430 if (rawoop == NULL) return NULL;
3431 for (DUIterator_Fast imax, i = rawoop->fast_outs(imax); i < imax; i++) {
3432 Node* storestore = rawoop->fast_out(i);
3433 if (storestore->is_MemBarStoreStore()) {
3434 return storestore->as_MemBarStoreStore();
3435 }
3436 }
3437 return NULL;
3438 }
3439
3440 //----------------------------- loop predicates ---------------------------
3441
3442 //------------------------------add_predicate_impl----------------------------
3443 void GraphKit::add_predicate_impl(Deoptimization::DeoptReason reason, int nargs) {
3444 // Too many traps seen?
3445 if (too_many_traps(reason)) {
3446 #ifdef ASSERT
3447 if (TraceLoopPredicate) {
3448 int tc = C->trap_count(reason);
3449 tty->print("too many traps=%s tcount=%d in ",
3450 Deoptimization::trap_reason_name(reason), tc);
3451 method()->print(); // which method has too many predicate traps
3452 tty->cr();
3453 }
3454 #endif
3455 // We cannot afford to take more traps here,
3456 // do not generate predicate.
3457 return;
3458 }
3459
3460 Node *cont = _gvn.intcon(1);
3461 Node* opq = _gvn.transform(new (C) Opaque1Node(C, cont));
3462 Node *bol = _gvn.transform(new (C) Conv2BNode(opq));
3463 IfNode* iff = create_and_map_if(control(), bol, PROB_MAX, COUNT_UNKNOWN);
3464 Node* iffalse = _gvn.transform(new (C) IfFalseNode(iff));
3465 C->add_predicate_opaq(opq);
3466 {
3467 PreserveJVMState pjvms(this);
3468 set_control(iffalse);
3469 inc_sp(nargs);
3470 uncommon_trap(reason, Deoptimization::Action_maybe_recompile);
3471 }
3472 Node* iftrue = _gvn.transform(new (C) IfTrueNode(iff));
3473 set_control(iftrue);
3474 }
3475
3476 //------------------------------add_predicate---------------------------------
3477 void GraphKit::add_predicate(int nargs) {
3478 if (UseLoopPredicate) {
3479 add_predicate_impl(Deoptimization::Reason_predicate, nargs);
3480 }
3481 // loop's limit check predicate should be near the loop.
3482 if (LoopLimitCheck) {
3483 add_predicate_impl(Deoptimization::Reason_loop_limit_check, nargs);
3484 }
3485 }
3486
3487 //----------------------------- store barriers ----------------------------
3488 #define __ ideal.
3489
3490 void GraphKit::sync_kit(IdealKit& ideal) {
3491 set_all_memory(__ merged_memory());
3492 set_i_o(__ i_o());
3493 set_control(__ ctrl());
3494 }
3495
3496 void GraphKit::final_sync(IdealKit& ideal) {
3497 // Final sync IdealKit and graphKit.
3498 sync_kit(ideal);
3499 }
3500
3501 // vanilla/CMS post barrier
3502 // Insert a write-barrier store. This is to let generational GC work; we have
3503 // to flag all oop-stores before the next GC point.
3504 void GraphKit::write_barrier_post(Node* oop_store,
3505 Node* obj,
3506 Node* adr,
3507 uint adr_idx,
3508 Node* val,
3509 bool use_precise) {
3510 // No store check needed if we're storing a NULL or an old object
3511 // (latter case is probably a string constant). The concurrent
3512 // mark sweep garbage collector, however, needs to have all nonNull
3513 // oop updates flagged via card-marks.
3514 if (val != NULL && val->is_Con()) {
3515 // must be either an oop or NULL
3516 const Type* t = val->bottom_type();
3517 if (t == TypePtr::NULL_PTR || t == Type::TOP)
3518 // stores of null never (?) need barriers
3519 return;
3520 ciObject* con = t->is_oopptr()->const_oop();
3521 if (con != NULL
3522 && con->is_perm()
3523 && Universe::heap()->can_elide_permanent_oop_store_barriers())
3524 // no store barrier needed, because no old-to-new ref created
3525 return;
3526 }
3527
3528 if (use_ReduceInitialCardMarks()
3529 && obj == just_allocated_object(control())) {
3530 // We can skip marks on a freshly-allocated object in Eden.
3531 // Keep this code in sync with new_store_pre_barrier() in runtime.cpp.
3532 // That routine informs GC to take appropriate compensating steps,
3533 // upon a slow-path allocation, so as to make this card-mark
3534 // elision safe.
3535 return;
3536 }
3537
3538 if (!use_precise) {
3539 // All card marks for a (non-array) instance are in one place:
3540 adr = obj;
3541 }
3542 // (Else it's an array (or unknown), and we want more precise card marks.)
3543 assert(adr != NULL, "");
3544
3545 IdealKit ideal(this, true);
3546
3547 // Convert the pointer to an int prior to doing math on it
3548 Node* cast = __ CastPX(__ ctrl(), adr);
3549
3550 // Divide by card size
3551 assert(Universe::heap()->barrier_set()->kind() == BarrierSet::CardTableModRef,
3552 "Only one we handle so far.");
3553 Node* card_offset = __ URShiftX( cast, __ ConI(CardTableModRefBS::card_shift) );
3554
3555 // Combine card table base and card offset
3556 Node* card_adr = __ AddP(__ top(), byte_map_base_node(), card_offset );
3557
3558 // Get the alias_index for raw card-mark memory
3559 int adr_type = Compile::AliasIdxRaw;
3560 Node* zero = __ ConI(0); // Dirty card value
3561 BasicType bt = T_BYTE;
3562
3563 if (UseCondCardMark) {
3564 // The classic GC reference write barrier is typically implemented
3565 // as a store into the global card mark table. Unfortunately
3566 // unconditional stores can result in false sharing and excessive
3567 // coherence traffic as well as false transactional aborts.
3568 // UseCondCardMark enables MP "polite" conditional card mark
3569 // stores. In theory we could relax the load from ctrl() to
3570 // no_ctrl, but that doesn't buy much latitude.
3571 Node* card_val = __ load( __ ctrl(), card_adr, TypeInt::BYTE, bt, adr_type);
3572 __ if_then(card_val, BoolTest::ne, zero);
3573 }
3574
3575 // Smash zero into card
3576 if( !UseConcMarkSweepGC ) {
3577 __ store(__ ctrl(), card_adr, zero, bt, adr_type);
3578 } else {
3579 // Specialized path for CM store barrier
3580 __ storeCM(__ ctrl(), card_adr, zero, oop_store, adr_idx, bt, adr_type);
3581 }
3582
3583 if (UseCondCardMark) {
3584 __ end_if();
3585 }
3586
3587 // Final sync IdealKit and GraphKit.
3588 final_sync(ideal);
3589 }
3590
3591 // G1 pre/post barriers
3592 void GraphKit::g1_write_barrier_pre(bool do_load,
3593 Node* obj,
3594 Node* adr,
3595 uint alias_idx,
3596 Node* val,
3597 const TypeOopPtr* val_type,
3598 Node* pre_val,
3599 BasicType bt) {
3600
3601 // Some sanity checks
3602 // Note: val is unused in this routine.
3603
3604 if (do_load) {
3605 // We need to generate the load of the previous value
3606 assert(obj != NULL, "must have a base");
3607 assert(adr != NULL, "where are loading from?");
3608 assert(pre_val == NULL, "loaded already?");
3609 assert(val_type != NULL, "need a type");
3610 } else {
3611 // In this case both val_type and alias_idx are unused.
3612 assert(pre_val != NULL, "must be loaded already");
3613 assert(pre_val->bottom_type()->basic_type() == T_OBJECT, "or we shouldn't be here");
3614 }
3615 assert(bt == T_OBJECT, "or we shouldn't be here");
3616
3617 IdealKit ideal(this, true);
3618
3619 Node* tls = __ thread(); // ThreadLocalStorage
3620
3621 Node* no_ctrl = NULL;
3622 Node* no_base = __ top();
3623 Node* zero = __ ConI(0);
3624 Node* zeroX = __ ConX(0);
3625
3626 float likely = PROB_LIKELY(0.999);
3627 float unlikely = PROB_UNLIKELY(0.999);
3628
3629 BasicType active_type = in_bytes(PtrQueue::byte_width_of_active()) == 4 ? T_INT : T_BYTE;
3630 assert(in_bytes(PtrQueue::byte_width_of_active()) == 4 || in_bytes(PtrQueue::byte_width_of_active()) == 1, "flag width");
3631
3632 // Offsets into the thread
3633 const int marking_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 648
3634 PtrQueue::byte_offset_of_active());
3635 const int index_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 656
3636 PtrQueue::byte_offset_of_index());
3637 const int buffer_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 652
3638 PtrQueue::byte_offset_of_buf());
3639
3640 // Now the actual pointers into the thread
3641 Node* marking_adr = __ AddP(no_base, tls, __ ConX(marking_offset));
3642 Node* buffer_adr = __ AddP(no_base, tls, __ ConX(buffer_offset));
3643 Node* index_adr = __ AddP(no_base, tls, __ ConX(index_offset));
3644
3645 // Now some of the values
3646 Node* marking = __ load(__ ctrl(), marking_adr, TypeInt::INT, active_type, Compile::AliasIdxRaw);
3647
3648 // if (!marking)
3649 __ if_then(marking, BoolTest::ne, zero, unlikely); {
3650 BasicType index_bt = TypeX_X->basic_type();
3651 assert(sizeof(size_t) == type2aelembytes(index_bt), "Loading G1 PtrQueue::_index with wrong size.");
3652 Node* index = __ load(__ ctrl(), index_adr, TypeX_X, index_bt, Compile::AliasIdxRaw);
3653
3654 if (do_load) {
3655 // load original value
3656 // alias_idx correct??
3657 pre_val = __ load(__ ctrl(), adr, val_type, bt, alias_idx);
3658 }
3659
3660 // if (pre_val != NULL)
3661 __ if_then(pre_val, BoolTest::ne, null()); {
3662 Node* buffer = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw);
3663
3664 // is the queue for this thread full?
3665 __ if_then(index, BoolTest::ne, zeroX, likely); {
3666
3667 // decrement the index
3668 Node* next_index = _gvn.transform(new (C) SubXNode(index, __ ConX(sizeof(intptr_t))));
3669
3670 // Now get the buffer location we will log the previous value into and store it
3671 Node *log_addr = __ AddP(no_base, buffer, next_index);
3672 __ store(__ ctrl(), log_addr, pre_val, T_OBJECT, Compile::AliasIdxRaw, StoreNode::release);
3673 // update the index
3674 __ store(__ ctrl(), index_adr, next_index, index_bt, Compile::AliasIdxRaw);
3675
3676 } __ else_(); {
3677
3678 // logging buffer is full, call the runtime
3679 const TypeFunc *tf = OptoRuntime::g1_wb_pre_Type();
3680 __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_pre), "g1_wb_pre", pre_val, tls);
3681 } __ end_if(); // (!index)
3682 } __ end_if(); // (pre_val != NULL)
3683 } __ end_if(); // (!marking)
3684
3685 // Final sync IdealKit and GraphKit.
3686 final_sync(ideal);
3687 }
3688
3689 //
3690 // Update the card table and add card address to the queue
3691 //
3692 void GraphKit::g1_mark_card(IdealKit& ideal,
3693 Node* card_adr,
3694 Node* oop_store,
3695 uint oop_alias_idx,
3696 Node* index,
3697 Node* index_adr,
3698 Node* buffer,
3699 const TypeFunc* tf) {
3700
3701 Node* zero = __ ConI(0);
3702 Node* zeroX = __ ConX(0);
3703 Node* no_base = __ top();
3704 BasicType card_bt = T_BYTE;
3705 // Smash zero into card. MUST BE ORDERED WRT TO STORE
3706 __ storeCM(__ ctrl(), card_adr, zero, oop_store, oop_alias_idx, card_bt, Compile::AliasIdxRaw);
3707
3708 // Now do the queue work
3709 __ if_then(index, BoolTest::ne, zeroX); {
3710
3711 Node* next_index = _gvn.transform(new (C) SubXNode(index, __ ConX(sizeof(intptr_t))));
3712 Node* log_addr = __ AddP(no_base, buffer, next_index);
3713
3714 __ store(__ ctrl(), log_addr, card_adr, T_ADDRESS, Compile::AliasIdxRaw, StoreNode::release);
3715 __ store(__ ctrl(), index_adr, next_index, TypeX_X->basic_type(), Compile::AliasIdxRaw, StoreNode::release);
3716
3717 } __ else_(); {
3718 __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_post), "g1_wb_post", card_adr, __ thread());
3719 } __ end_if();
3720
3721 }
3722
3723 void GraphKit::g1_write_barrier_post(Node* oop_store,
3724 Node* obj,
3725 Node* adr,
3726 uint alias_idx,
3727 Node* val,
3728 BasicType bt,
3729 bool use_precise) {
3730 // If we are writing a NULL then we need no post barrier
3731
3732 if (val != NULL && val->is_Con() && val->bottom_type() == TypePtr::NULL_PTR) {
3733 // Must be NULL
3734 const Type* t = val->bottom_type();
3735 assert(t == Type::TOP || t == TypePtr::NULL_PTR, "must be NULL");
3736 // No post barrier if writing NULLx
3737 return;
3738 }
3739
3740 if (!use_precise) {
3741 // All card marks for a (non-array) instance are in one place:
3742 adr = obj;
3743 }
3744 // (Else it's an array (or unknown), and we want more precise card marks.)
3745 assert(adr != NULL, "");
3746
3747 IdealKit ideal(this, true);
3748
3749 Node* tls = __ thread(); // ThreadLocalStorage
3750
3751 Node* no_base = __ top();
3752 float likely = PROB_LIKELY(0.999);
3753 float unlikely = PROB_UNLIKELY(0.999);
3754 Node* young_card = __ ConI((jint)G1SATBCardTableModRefBS::g1_young_card_val());
3755 Node* dirty_card = __ ConI((jint)CardTableModRefBS::dirty_card_val());
3756 Node* zeroX = __ ConX(0);
3757
3758 // Get the alias_index for raw card-mark memory
3759 const TypePtr* card_type = TypeRawPtr::BOTTOM;
3760
3761 const TypeFunc *tf = OptoRuntime::g1_wb_post_Type();
3762
3763 // Offsets into the thread
3764 const int index_offset = in_bytes(JavaThread::dirty_card_queue_offset() +
3765 PtrQueue::byte_offset_of_index());
3766 const int buffer_offset = in_bytes(JavaThread::dirty_card_queue_offset() +
3767 PtrQueue::byte_offset_of_buf());
3768
3769 // Pointers into the thread
3770
3771 Node* buffer_adr = __ AddP(no_base, tls, __ ConX(buffer_offset));
3772 Node* index_adr = __ AddP(no_base, tls, __ ConX(index_offset));
3773
3774 // Now some values
3775 // Use ctrl to avoid hoisting these values past a safepoint, which could
3776 // potentially reset these fields in the JavaThread.
3777 Node* index = __ load(__ ctrl(), index_adr, TypeX_X, TypeX_X->basic_type(), Compile::AliasIdxRaw);
3778 Node* buffer = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw);
3779
3780 // Convert the store obj pointer to an int prior to doing math on it
3781 // Must use ctrl to prevent "integerized oop" existing across safepoint
3782 Node* cast = __ CastPX(__ ctrl(), adr);
3783
3784 // Divide pointer by card size
3785 Node* card_offset = __ URShiftX( cast, __ ConI(CardTableModRefBS::card_shift) );
3786
3787 // Combine card table base and card offset
3788 Node* card_adr = __ AddP(no_base, byte_map_base_node(), card_offset );
3789
3790 // If we know the value being stored does it cross regions?
3791
3792 if (val != NULL) {
3793 // Does the store cause us to cross regions?
3794
3795 // Should be able to do an unsigned compare of region_size instead of
3796 // and extra shift. Do we have an unsigned compare??
3797 // Node* region_size = __ ConI(1 << HeapRegion::LogOfHRGrainBytes);
3798 Node* xor_res = __ URShiftX ( __ XorX( cast, __ CastPX(__ ctrl(), val)), __ ConI(HeapRegion::LogOfHRGrainBytes));
3799
3800 // if (xor_res == 0) same region so skip
3801 __ if_then(xor_res, BoolTest::ne, zeroX); {
3802
3803 // No barrier if we are storing a NULL
3804 __ if_then(val, BoolTest::ne, null(), unlikely); {
3805
3806 // Ok must mark the card if not already dirty
3807
3808 // load the original value of the card
3809 Node* card_val = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw);
3810
3811 __ if_then(card_val, BoolTest::ne, young_card); {
3812 sync_kit(ideal);
3813 // Use Op_MemBarVolatile to achieve the effect of a StoreLoad barrier.
3814 insert_mem_bar(Op_MemBarVolatile, oop_store);
3815 __ sync_kit(this);
3816
3817 Node* card_val_reload = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw);
3818 __ if_then(card_val_reload, BoolTest::ne, dirty_card); {
3819 g1_mark_card(ideal, card_adr, oop_store, alias_idx, index, index_adr, buffer, tf);
3820 } __ end_if();
3821 } __ end_if();
3822 } __ end_if();
3823 } __ end_if();
3824 } else {
3825 // Object.clone() instrinsic uses this path.
3826 g1_mark_card(ideal, card_adr, oop_store, alias_idx, index, index_adr, buffer, tf);
3827 }
3828
3829 // Final sync IdealKit and GraphKit.
3830 final_sync(ideal);
3831 }
3832 #undef __
3833
3834
3835
3836 Node* GraphKit::load_String_offset(Node* ctrl, Node* str) {
3837 if (java_lang_String::has_offset_field()) {
3838 int offset_offset = java_lang_String::offset_offset_in_bytes();
3839 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
3840 false, NULL, 0);
3841 const TypePtr* offset_field_type = string_type->add_offset(offset_offset);
3842 int offset_field_idx = C->get_alias_index(offset_field_type);
3843 return make_load(ctrl,
3844 basic_plus_adr(str, str, offset_offset),
3845 TypeInt::INT, T_INT, offset_field_idx);
3846 } else {
3847 return intcon(0);
3848 }
3849 }
3850
3851 Node* GraphKit::load_String_length(Node* ctrl, Node* str) {
3852 if (java_lang_String::has_count_field()) {
3853 int count_offset = java_lang_String::count_offset_in_bytes();
3854 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
3855 false, NULL, 0);
3856 const TypePtr* count_field_type = string_type->add_offset(count_offset);
3857 int count_field_idx = C->get_alias_index(count_field_type);
3858 return make_load(ctrl,
3859 basic_plus_adr(str, str, count_offset),
3860 TypeInt::INT, T_INT, count_field_idx);
3861 } else {
3862 return load_array_length(load_String_value(ctrl, str));
3863 }
3864 }
3865
3866 Node* GraphKit::load_String_value(Node* ctrl, Node* str) {
3867 int value_offset = java_lang_String::value_offset_in_bytes();
3868 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
3869 false, NULL, 0);
3870 const TypePtr* value_field_type = string_type->add_offset(value_offset);
3871 const TypeAryPtr* value_type = TypeAryPtr::make(TypePtr::NotNull,
3872 TypeAry::make(TypeInt::CHAR,TypeInt::POS),
3873 ciTypeArrayKlass::make(T_CHAR), true, 0);
3874 int value_field_idx = C->get_alias_index(value_field_type);
3875 return make_load(ctrl, basic_plus_adr(str, str, value_offset),
3876 value_type, T_OBJECT, value_field_idx);
3877 }
3878
3879 void GraphKit::store_String_offset(Node* ctrl, Node* str, Node* value) {
3880 int offset_offset = java_lang_String::offset_offset_in_bytes();
3881 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
3882 false, NULL, 0);
3883 const TypePtr* offset_field_type = string_type->add_offset(offset_offset);
3884 int offset_field_idx = C->get_alias_index(offset_field_type);
3885 store_to_memory(ctrl, basic_plus_adr(str, offset_offset),
3886 value, T_INT, offset_field_idx);
3887 }
3888
3889 void GraphKit::store_String_value(Node* ctrl, Node* str, Node* value) {
3890 int value_offset = java_lang_String::value_offset_in_bytes();
3891 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
3892 false, NULL, 0);
3893 const TypePtr* value_field_type = string_type->add_offset(value_offset);
3894 const TypeAryPtr* value_type = TypeAryPtr::make(TypePtr::NotNull,
3895 TypeAry::make(TypeInt::CHAR,TypeInt::POS),
3896 ciTypeArrayKlass::make(T_CHAR), true, 0);
3897 int value_field_idx = C->get_alias_index(value_field_type);
3898 store_to_memory(ctrl, basic_plus_adr(str, value_offset),
3899 value, T_OBJECT, value_field_idx);
3900 }
3901
3902 void GraphKit::store_String_length(Node* ctrl, Node* str, Node* value) {
3903 int count_offset = java_lang_String::count_offset_in_bytes();
3904 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
3905 false, NULL, 0);
3906 const TypePtr* count_field_type = string_type->add_offset(count_offset);
3907 int count_field_idx = C->get_alias_index(count_field_type);
3908 store_to_memory(ctrl, basic_plus_adr(str, count_offset),
3909 value, T_INT, count_field_idx);
3910 }