1 /*
2 * Copyright (c) 2001, 2013, 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/castnode.hpp"
34 #include "opto/convertnode.hpp"
35 #include "opto/graphKit.hpp"
36 #include "opto/idealKit.hpp"
37 #include "opto/intrinsicnode.hpp"
38 #include "opto/locknode.hpp"
39 #include "opto/machnode.hpp"
40 #include "opto/opaquenode.hpp"
41 #include "opto/parse.hpp"
42 #include "opto/rootnode.hpp"
43 #include "opto/runtime.hpp"
44 #include "opto/threadnode.hpp"
45 #include "runtime/deoptimization.hpp"
46 #include "runtime/sharedRuntime.hpp"
47
48 //----------------------------GraphKit-----------------------------------------
49 // Main utility constructor.
50 GraphKit::GraphKit(JVMState* jvms)
51 : Phase(Phase::Parser),
52 _env(C->env()),
53 _gvn(*C->initial_gvn())
54 {
55 _exceptions = jvms->map()->next_exception();
56 if (_exceptions != NULL) jvms->map()->set_next_exception(NULL);
57 set_jvms(jvms);
58 }
59
60 // Private constructor for parser.
61 GraphKit::GraphKit()
62 : Phase(Phase::Parser),
63 _env(C->env()),
64 _gvn(*C->initial_gvn())
65 {
66 _exceptions = NULL;
67 set_map(NULL);
68 debug_only(_sp = -99);
69 debug_only(set_bci(-99));
70 }
71
72
73
74 //---------------------------clean_stack---------------------------------------
75 // Clear away rubbish from the stack area of the JVM state.
76 // This destroys any arguments that may be waiting on the stack.
77 void GraphKit::clean_stack(int from_sp) {
78 SafePointNode* map = this->map();
79 JVMState* jvms = this->jvms();
80 int stk_size = jvms->stk_size();
81 int stkoff = jvms->stkoff();
82 Node* top = this->top();
83 for (int i = from_sp; i < stk_size; i++) {
84 if (map->in(stkoff + i) != top) {
85 map->set_req(stkoff + i, top);
86 }
87 }
88 }
89
90
91 //--------------------------------sync_jvms-----------------------------------
92 // Make sure our current jvms agrees with our parse state.
93 JVMState* GraphKit::sync_jvms() const {
94 JVMState* jvms = this->jvms();
95 jvms->set_bci(bci()); // Record the new bci in the JVMState
96 jvms->set_sp(sp()); // Record the new sp in the JVMState
97 assert(jvms_in_sync(), "jvms is now in sync");
98 return jvms;
99 }
100
101 //--------------------------------sync_jvms_for_reexecute---------------------
102 // Make sure our current jvms agrees with our parse state. This version
103 // uses the reexecute_sp for reexecuting bytecodes.
104 JVMState* GraphKit::sync_jvms_for_reexecute() {
105 JVMState* jvms = this->jvms();
106 jvms->set_bci(bci()); // Record the new bci in the JVMState
107 jvms->set_sp(reexecute_sp()); // Record the new sp in the JVMState
108 return jvms;
109 }
110
111 #ifdef ASSERT
112 bool GraphKit::jvms_in_sync() const {
113 Parse* parse = is_Parse();
114 if (parse == NULL) {
115 if (bci() != jvms()->bci()) return false;
116 if (sp() != (int)jvms()->sp()) return false;
117 return true;
118 }
119 if (jvms()->method() != parse->method()) return false;
120 if (jvms()->bci() != parse->bci()) return false;
121 int jvms_sp = jvms()->sp();
122 if (jvms_sp != parse->sp()) return false;
123 int jvms_depth = jvms()->depth();
124 if (jvms_depth != parse->depth()) return false;
125 return true;
126 }
127
128 // Local helper checks for special internal merge points
129 // used to accumulate and merge exception states.
130 // They are marked by the region's in(0) edge being the map itself.
131 // Such merge points must never "escape" into the parser at large,
132 // until they have been handed to gvn.transform.
133 static bool is_hidden_merge(Node* reg) {
134 if (reg == NULL) return false;
135 if (reg->is_Phi()) {
136 reg = reg->in(0);
137 if (reg == NULL) return false;
138 }
139 return reg->is_Region() && reg->in(0) != NULL && reg->in(0)->is_Root();
140 }
141
142 void GraphKit::verify_map() const {
143 if (map() == NULL) return; // null map is OK
144 assert(map()->req() <= jvms()->endoff(), "no extra garbage on map");
145 assert(!map()->has_exceptions(), "call add_exception_states_from 1st");
146 assert(!is_hidden_merge(control()), "call use_exception_state, not set_map");
147 }
148
149 void GraphKit::verify_exception_state(SafePointNode* ex_map) {
150 assert(ex_map->next_exception() == NULL, "not already part of a chain");
151 assert(has_saved_ex_oop(ex_map), "every exception state has an ex_oop");
152 }
153 #endif
154
155 //---------------------------stop_and_kill_map---------------------------------
156 // Set _map to NULL, signalling a stop to further bytecode execution.
157 // First smash the current map's control to a constant, to mark it dead.
158 void GraphKit::stop_and_kill_map() {
159 SafePointNode* dead_map = stop();
160 if (dead_map != NULL) {
161 dead_map->disconnect_inputs(NULL, C); // Mark the map as killed.
162 assert(dead_map->is_killed(), "must be so marked");
163 }
164 }
165
166
167 //--------------------------------stopped--------------------------------------
168 // Tell if _map is NULL, or control is top.
169 bool GraphKit::stopped() {
170 if (map() == NULL) return true;
171 else if (control() == top()) return true;
172 else return false;
173 }
174
175
176 //-----------------------------has_ex_handler----------------------------------
177 // Tell if this method or any caller method has exception handlers.
178 bool GraphKit::has_ex_handler() {
179 for (JVMState* jvmsp = jvms(); jvmsp != NULL; jvmsp = jvmsp->caller()) {
180 if (jvmsp->has_method() && jvmsp->method()->has_exception_handlers()) {
181 return true;
182 }
183 }
184 return false;
185 }
186
187 //------------------------------save_ex_oop------------------------------------
188 // Save an exception without blowing stack contents or other JVM state.
189 void GraphKit::set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop) {
190 assert(!has_saved_ex_oop(ex_map), "clear ex-oop before setting again");
191 ex_map->add_req(ex_oop);
192 debug_only(verify_exception_state(ex_map));
193 }
194
195 inline static Node* common_saved_ex_oop(SafePointNode* ex_map, bool clear_it) {
196 assert(GraphKit::has_saved_ex_oop(ex_map), "ex_oop must be there");
197 Node* ex_oop = ex_map->in(ex_map->req()-1);
198 if (clear_it) ex_map->del_req(ex_map->req()-1);
199 return ex_oop;
200 }
201
202 //-----------------------------saved_ex_oop------------------------------------
203 // Recover a saved exception from its map.
204 Node* GraphKit::saved_ex_oop(SafePointNode* ex_map) {
205 return common_saved_ex_oop(ex_map, false);
206 }
207
208 //--------------------------clear_saved_ex_oop---------------------------------
209 // Erase a previously saved exception from its map.
210 Node* GraphKit::clear_saved_ex_oop(SafePointNode* ex_map) {
211 return common_saved_ex_oop(ex_map, true);
212 }
213
214 #ifdef ASSERT
215 //---------------------------has_saved_ex_oop----------------------------------
216 // Erase a previously saved exception from its map.
217 bool GraphKit::has_saved_ex_oop(SafePointNode* ex_map) {
218 return ex_map->req() == ex_map->jvms()->endoff()+1;
219 }
220 #endif
221
222 //-------------------------make_exception_state--------------------------------
223 // Turn the current JVM state into an exception state, appending the ex_oop.
224 SafePointNode* GraphKit::make_exception_state(Node* ex_oop) {
225 sync_jvms();
226 SafePointNode* ex_map = stop(); // do not manipulate this map any more
227 set_saved_ex_oop(ex_map, ex_oop);
228 return ex_map;
229 }
230
231
232 //--------------------------add_exception_state--------------------------------
233 // Add an exception to my list of exceptions.
234 void GraphKit::add_exception_state(SafePointNode* ex_map) {
235 if (ex_map == NULL || ex_map->control() == top()) {
236 return;
237 }
238 #ifdef ASSERT
239 verify_exception_state(ex_map);
240 if (has_exceptions()) {
241 assert(ex_map->jvms()->same_calls_as(_exceptions->jvms()), "all collected exceptions must come from the same place");
242 }
243 #endif
244
245 // If there is already an exception of exactly this type, merge with it.
246 // In particular, null-checks and other low-level exceptions common up here.
247 Node* ex_oop = saved_ex_oop(ex_map);
248 const Type* ex_type = _gvn.type(ex_oop);
249 if (ex_oop == top()) {
250 // No action needed.
251 return;
252 }
253 assert(ex_type->isa_instptr(), "exception must be an instance");
254 for (SafePointNode* e2 = _exceptions; e2 != NULL; e2 = e2->next_exception()) {
255 const Type* ex_type2 = _gvn.type(saved_ex_oop(e2));
256 // We check sp also because call bytecodes can generate exceptions
257 // both before and after arguments are popped!
258 if (ex_type2 == ex_type
259 && e2->_jvms->sp() == ex_map->_jvms->sp()) {
260 combine_exception_states(ex_map, e2);
261 return;
262 }
263 }
264
265 // No pre-existing exception of the same type. Chain it on the list.
266 push_exception_state(ex_map);
267 }
268
269 //-----------------------add_exception_states_from-----------------------------
270 void GraphKit::add_exception_states_from(JVMState* jvms) {
271 SafePointNode* ex_map = jvms->map()->next_exception();
272 if (ex_map != NULL) {
273 jvms->map()->set_next_exception(NULL);
274 for (SafePointNode* next_map; ex_map != NULL; ex_map = next_map) {
275 next_map = ex_map->next_exception();
276 ex_map->set_next_exception(NULL);
277 add_exception_state(ex_map);
278 }
279 }
280 }
281
282 //-----------------------transfer_exceptions_into_jvms-------------------------
283 JVMState* GraphKit::transfer_exceptions_into_jvms() {
284 if (map() == NULL) {
285 // We need a JVMS to carry the exceptions, but the map has gone away.
286 // Create a scratch JVMS, cloned from any of the exception states...
287 if (has_exceptions()) {
288 _map = _exceptions;
289 _map = clone_map();
290 _map->set_next_exception(NULL);
291 clear_saved_ex_oop(_map);
292 debug_only(verify_map());
293 } else {
294 // ...or created from scratch
295 JVMState* jvms = new (C) JVMState(_method, NULL);
296 jvms->set_bci(_bci);
297 jvms->set_sp(_sp);
298 jvms->set_map(new (C) SafePointNode(TypeFunc::Parms, jvms));
299 set_jvms(jvms);
300 for (uint i = 0; i < map()->req(); i++) map()->init_req(i, top());
301 set_all_memory(top());
302 while (map()->req() < jvms->endoff()) map()->add_req(top());
303 }
304 // (This is a kludge, in case you didn't notice.)
305 set_control(top());
306 }
307 JVMState* jvms = sync_jvms();
308 assert(!jvms->map()->has_exceptions(), "no exceptions on this map yet");
309 jvms->map()->set_next_exception(_exceptions);
310 _exceptions = NULL; // done with this set of exceptions
311 return jvms;
312 }
313
314 static inline void add_n_reqs(Node* dstphi, Node* srcphi) {
315 assert(is_hidden_merge(dstphi), "must be a special merge node");
316 assert(is_hidden_merge(srcphi), "must be a special merge node");
317 uint limit = srcphi->req();
318 for (uint i = PhiNode::Input; i < limit; i++) {
319 dstphi->add_req(srcphi->in(i));
320 }
321 }
322 static inline void add_one_req(Node* dstphi, Node* src) {
323 assert(is_hidden_merge(dstphi), "must be a special merge node");
324 assert(!is_hidden_merge(src), "must not be a special merge node");
325 dstphi->add_req(src);
326 }
327
328 //-----------------------combine_exception_states------------------------------
329 // This helper function combines exception states by building phis on a
330 // specially marked state-merging region. These regions and phis are
331 // untransformed, and can build up gradually. The region is marked by
332 // having a control input of its exception map, rather than NULL. Such
333 // regions do not appear except in this function, and in use_exception_state.
334 void GraphKit::combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map) {
335 if (failing()) return; // dying anyway...
336 JVMState* ex_jvms = ex_map->_jvms;
337 assert(ex_jvms->same_calls_as(phi_map->_jvms), "consistent call chains");
338 assert(ex_jvms->stkoff() == phi_map->_jvms->stkoff(), "matching locals");
339 assert(ex_jvms->sp() == phi_map->_jvms->sp(), "matching stack sizes");
340 assert(ex_jvms->monoff() == phi_map->_jvms->monoff(), "matching JVMS");
341 assert(ex_jvms->scloff() == phi_map->_jvms->scloff(), "matching scalar replaced objects");
342 assert(ex_map->req() == phi_map->req(), "matching maps");
343 uint tos = ex_jvms->stkoff() + ex_jvms->sp();
344 Node* hidden_merge_mark = root();
345 Node* region = phi_map->control();
346 MergeMemNode* phi_mem = phi_map->merged_memory();
347 MergeMemNode* ex_mem = ex_map->merged_memory();
348 if (region->in(0) != hidden_merge_mark) {
349 // The control input is not (yet) a specially-marked region in phi_map.
350 // Make it so, and build some phis.
351 region = new (C) RegionNode(2);
352 _gvn.set_type(region, Type::CONTROL);
353 region->set_req(0, hidden_merge_mark); // marks an internal ex-state
354 region->init_req(1, phi_map->control());
355 phi_map->set_control(region);
356 Node* io_phi = PhiNode::make(region, phi_map->i_o(), Type::ABIO);
357 record_for_igvn(io_phi);
358 _gvn.set_type(io_phi, Type::ABIO);
359 phi_map->set_i_o(io_phi);
360 for (MergeMemStream mms(phi_mem); mms.next_non_empty(); ) {
361 Node* m = mms.memory();
362 Node* m_phi = PhiNode::make(region, m, Type::MEMORY, mms.adr_type(C));
363 record_for_igvn(m_phi);
364 _gvn.set_type(m_phi, Type::MEMORY);
365 mms.set_memory(m_phi);
366 }
367 }
368
369 // Either or both of phi_map and ex_map might already be converted into phis.
370 Node* ex_control = ex_map->control();
371 // if there is special marking on ex_map also, we add multiple edges from src
372 bool add_multiple = (ex_control->in(0) == hidden_merge_mark);
373 // how wide was the destination phi_map, originally?
374 uint orig_width = region->req();
375
376 if (add_multiple) {
377 add_n_reqs(region, ex_control);
378 add_n_reqs(phi_map->i_o(), ex_map->i_o());
379 } else {
380 // ex_map has no merges, so we just add single edges everywhere
381 add_one_req(region, ex_control);
382 add_one_req(phi_map->i_o(), ex_map->i_o());
383 }
384 for (MergeMemStream mms(phi_mem, ex_mem); mms.next_non_empty2(); ) {
385 if (mms.is_empty()) {
386 // get a copy of the base memory, and patch some inputs into it
387 const TypePtr* adr_type = mms.adr_type(C);
388 Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
389 assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
390 mms.set_memory(phi);
391 // Prepare to append interesting stuff onto the newly sliced phi:
392 while (phi->req() > orig_width) phi->del_req(phi->req()-1);
393 }
394 // Append stuff from ex_map:
395 if (add_multiple) {
396 add_n_reqs(mms.memory(), mms.memory2());
397 } else {
398 add_one_req(mms.memory(), mms.memory2());
399 }
400 }
401 uint limit = ex_map->req();
402 for (uint i = TypeFunc::Parms; i < limit; i++) {
403 // Skip everything in the JVMS after tos. (The ex_oop follows.)
404 if (i == tos) i = ex_jvms->monoff();
405 Node* src = ex_map->in(i);
406 Node* dst = phi_map->in(i);
407 if (src != dst) {
408 PhiNode* phi;
409 if (dst->in(0) != region) {
410 dst = phi = PhiNode::make(region, dst, _gvn.type(dst));
411 record_for_igvn(phi);
412 _gvn.set_type(phi, phi->type());
413 phi_map->set_req(i, dst);
414 // Prepare to append interesting stuff onto the new phi:
415 while (dst->req() > orig_width) dst->del_req(dst->req()-1);
416 } else {
417 assert(dst->is_Phi(), "nobody else uses a hidden region");
418 phi = dst->as_Phi();
419 }
420 if (add_multiple && src->in(0) == ex_control) {
421 // Both are phis.
422 add_n_reqs(dst, src);
423 } else {
424 while (dst->req() < region->req()) add_one_req(dst, src);
425 }
426 const Type* srctype = _gvn.type(src);
427 if (phi->type() != srctype) {
428 const Type* dsttype = phi->type()->meet_speculative(srctype);
429 if (phi->type() != dsttype) {
430 phi->set_type(dsttype);
431 _gvn.set_type(phi, dsttype);
432 }
433 }
434 }
435 }
436 }
437
438 //--------------------------use_exception_state--------------------------------
439 Node* GraphKit::use_exception_state(SafePointNode* phi_map) {
440 if (failing()) { stop(); return top(); }
441 Node* region = phi_map->control();
442 Node* hidden_merge_mark = root();
443 assert(phi_map->jvms()->map() == phi_map, "sanity: 1-1 relation");
444 Node* ex_oop = clear_saved_ex_oop(phi_map);
445 if (region->in(0) == hidden_merge_mark) {
446 // Special marking for internal ex-states. Process the phis now.
447 region->set_req(0, region); // now it's an ordinary region
448 set_jvms(phi_map->jvms()); // ...so now we can use it as a map
449 // Note: Setting the jvms also sets the bci and sp.
450 set_control(_gvn.transform(region));
451 uint tos = jvms()->stkoff() + sp();
452 for (uint i = 1; i < tos; i++) {
453 Node* x = phi_map->in(i);
454 if (x->in(0) == region) {
455 assert(x->is_Phi(), "expected a special phi");
456 phi_map->set_req(i, _gvn.transform(x));
457 }
458 }
459 for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
460 Node* x = mms.memory();
461 if (x->in(0) == region) {
462 assert(x->is_Phi(), "nobody else uses a hidden region");
463 mms.set_memory(_gvn.transform(x));
464 }
465 }
466 if (ex_oop->in(0) == region) {
467 assert(ex_oop->is_Phi(), "expected a special phi");
468 ex_oop = _gvn.transform(ex_oop);
469 }
470 } else {
471 set_jvms(phi_map->jvms());
472 }
473
474 assert(!is_hidden_merge(phi_map->control()), "hidden ex. states cleared");
475 assert(!is_hidden_merge(phi_map->i_o()), "hidden ex. states cleared");
476 return ex_oop;
477 }
478
479 //---------------------------------java_bc-------------------------------------
480 Bytecodes::Code GraphKit::java_bc() const {
481 ciMethod* method = this->method();
482 int bci = this->bci();
483 if (method != NULL && bci != InvocationEntryBci)
484 return method->java_code_at_bci(bci);
485 else
486 return Bytecodes::_illegal;
487 }
488
489 void GraphKit::uncommon_trap_if_should_post_on_exceptions(Deoptimization::DeoptReason reason,
490 bool must_throw) {
491 // if the exception capability is set, then we will generate code
492 // to check the JavaThread.should_post_on_exceptions flag to see
493 // if we actually need to report exception events (for this
494 // thread). If we don't need to report exception events, we will
495 // take the normal fast path provided by add_exception_events. If
496 // exception event reporting is enabled for this thread, we will
497 // take the uncommon_trap in the BuildCutout below.
498
499 // first must access the should_post_on_exceptions_flag in this thread's JavaThread
500 Node* jthread = _gvn.transform(new (C) ThreadLocalNode());
501 Node* adr = basic_plus_adr(top(), jthread, in_bytes(JavaThread::should_post_on_exceptions_flag_offset()));
502 Node* should_post_flag = make_load(control(), adr, TypeInt::INT, T_INT, Compile::AliasIdxRaw, MemNode::unordered);
503
504 // Test the should_post_on_exceptions_flag vs. 0
505 Node* chk = _gvn.transform( new (C) CmpINode(should_post_flag, intcon(0)) );
506 Node* tst = _gvn.transform( new (C) BoolNode(chk, BoolTest::eq) );
507
508 // Branch to slow_path if should_post_on_exceptions_flag was true
509 { BuildCutout unless(this, tst, PROB_MAX);
510 // Do not try anything fancy if we're notifying the VM on every throw.
511 // Cf. case Bytecodes::_athrow in parse2.cpp.
512 uncommon_trap(reason, Deoptimization::Action_none,
513 (ciKlass*)NULL, (char*)NULL, must_throw);
514 }
515
516 }
517
518 //------------------------------builtin_throw----------------------------------
519 void GraphKit::builtin_throw(Deoptimization::DeoptReason reason, Node* arg) {
520 bool must_throw = true;
521
522 if (env()->jvmti_can_post_on_exceptions()) {
523 // check if we must post exception events, take uncommon trap if so
524 uncommon_trap_if_should_post_on_exceptions(reason, must_throw);
525 // here if should_post_on_exceptions is false
526 // continue on with the normal codegen
527 }
528
529 // If this particular condition has not yet happened at this
530 // bytecode, then use the uncommon trap mechanism, and allow for
531 // a future recompilation if several traps occur here.
532 // If the throw is hot, try to use a more complicated inline mechanism
533 // which keeps execution inside the compiled code.
534 bool treat_throw_as_hot = false;
535 ciMethodData* md = method()->method_data();
536
537 if (ProfileTraps) {
538 if (too_many_traps(reason)) {
539 treat_throw_as_hot = true;
540 }
541 // (If there is no MDO at all, assume it is early in
542 // execution, and that any deopts are part of the
543 // startup transient, and don't need to be remembered.)
544
545 // Also, if there is a local exception handler, treat all throws
546 // as hot if there has been at least one in this method.
547 if (C->trap_count(reason) != 0
548 && method()->method_data()->trap_count(reason) != 0
549 && has_ex_handler()) {
550 treat_throw_as_hot = true;
551 }
552 }
553
554 // If this throw happens frequently, an uncommon trap might cause
555 // a performance pothole. If there is a local exception handler,
556 // and if this particular bytecode appears to be deoptimizing often,
557 // let us handle the throw inline, with a preconstructed instance.
558 // Note: If the deopt count has blown up, the uncommon trap
559 // runtime is going to flush this nmethod, not matter what.
560 if (treat_throw_as_hot
561 && (!StackTraceInThrowable || OmitStackTraceInFastThrow)) {
562 // If the throw is local, we use a pre-existing instance and
563 // punt on the backtrace. This would lead to a missing backtrace
564 // (a repeat of 4292742) if the backtrace object is ever asked
565 // for its backtrace.
566 // Fixing this remaining case of 4292742 requires some flavor of
567 // escape analysis. Leave that for the future.
568 ciInstance* ex_obj = NULL;
569 switch (reason) {
570 case Deoptimization::Reason_null_check:
571 ex_obj = env()->NullPointerException_instance();
572 break;
573 case Deoptimization::Reason_div0_check:
574 ex_obj = env()->ArithmeticException_instance();
575 break;
576 case Deoptimization::Reason_range_check:
577 ex_obj = env()->ArrayIndexOutOfBoundsException_instance();
578 break;
579 case Deoptimization::Reason_class_check:
580 if (java_bc() == Bytecodes::_aastore) {
581 ex_obj = env()->ArrayStoreException_instance();
582 } else {
583 ex_obj = env()->ClassCastException_instance();
584 }
585 break;
586 }
587 if (failing()) { stop(); return; } // exception allocation might fail
588 if (ex_obj != NULL) {
589 // Cheat with a preallocated exception object.
590 if (C->log() != NULL)
591 C->log()->elem("hot_throw preallocated='1' reason='%s'",
592 Deoptimization::trap_reason_name(reason));
593 const TypeInstPtr* ex_con = TypeInstPtr::make(ex_obj);
594 Node* ex_node = _gvn.transform( ConNode::make(C, ex_con) );
595
596 // Clear the detail message of the preallocated exception object.
597 // Weblogic sometimes mutates the detail message of exceptions
598 // using reflection.
599 int offset = java_lang_Throwable::get_detailMessage_offset();
600 const TypePtr* adr_typ = ex_con->add_offset(offset);
601
602 Node *adr = basic_plus_adr(ex_node, ex_node, offset);
603 const TypeOopPtr* val_type = TypeOopPtr::make_from_klass(env()->String_klass());
604 // Conservatively release stores of object references.
605 Node *store = store_oop_to_object(control(), ex_node, adr, adr_typ, null(), val_type, T_OBJECT, MemNode::release);
606
607 add_exception_state(make_exception_state(ex_node));
608 return;
609 }
610 }
611
612 // %%% Maybe add entry to OptoRuntime which directly throws the exc.?
613 // It won't be much cheaper than bailing to the interp., since we'll
614 // have to pass up all the debug-info, and the runtime will have to
615 // create the stack trace.
616
617 // Usual case: Bail to interpreter.
618 // Reserve the right to recompile if we haven't seen anything yet.
619
620 assert(!Deoptimization::reason_is_speculate(reason), "unsupported");
621 Deoptimization::DeoptAction action = Deoptimization::Action_maybe_recompile;
622 if (treat_throw_as_hot
623 && (method()->method_data()->trap_recompiled_at(bci(), NULL)
624 || C->too_many_traps(reason))) {
625 // We cannot afford to take more traps here. Suffer in the interpreter.
626 if (C->log() != NULL)
627 C->log()->elem("hot_throw preallocated='0' reason='%s' mcount='%d'",
628 Deoptimization::trap_reason_name(reason),
629 C->trap_count(reason));
630 action = Deoptimization::Action_none;
631 }
632
633 // "must_throw" prunes the JVM state to include only the stack, if there
634 // are no local exception handlers. This should cut down on register
635 // allocation time and code size, by drastically reducing the number
636 // of in-edges on the call to the uncommon trap.
637
638 uncommon_trap(reason, action, (ciKlass*)NULL, (char*)NULL, must_throw);
639 }
640
641
642 //----------------------------PreserveJVMState---------------------------------
643 PreserveJVMState::PreserveJVMState(GraphKit* kit, bool clone_map) {
644 debug_only(kit->verify_map());
645 _kit = kit;
646 _map = kit->map(); // preserve the map
647 _sp = kit->sp();
648 kit->set_map(clone_map ? kit->clone_map() : NULL);
649 Compile::current()->inc_preserve_jvm_state();
650 #ifdef ASSERT
651 _bci = kit->bci();
652 Parse* parser = kit->is_Parse();
653 int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo();
654 _block = block;
655 #endif
656 }
657 PreserveJVMState::~PreserveJVMState() {
658 GraphKit* kit = _kit;
659 #ifdef ASSERT
660 assert(kit->bci() == _bci, "bci must not shift");
661 Parse* parser = kit->is_Parse();
662 int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo();
663 assert(block == _block, "block must not shift");
664 #endif
665 kit->set_map(_map);
666 kit->set_sp(_sp);
667 Compile::current()->dec_preserve_jvm_state();
668 }
669
670
671 //-----------------------------BuildCutout-------------------------------------
672 BuildCutout::BuildCutout(GraphKit* kit, Node* p, float prob, float cnt)
673 : PreserveJVMState(kit)
674 {
675 assert(p->is_Con() || p->is_Bool(), "test must be a bool");
676 SafePointNode* outer_map = _map; // preserved map is caller's
677 SafePointNode* inner_map = kit->map();
678 IfNode* iff = kit->create_and_map_if(outer_map->control(), p, prob, cnt);
679 outer_map->set_control(kit->gvn().transform( new (kit->C) IfTrueNode(iff) ));
680 inner_map->set_control(kit->gvn().transform( new (kit->C) IfFalseNode(iff) ));
681 }
682 BuildCutout::~BuildCutout() {
683 GraphKit* kit = _kit;
684 assert(kit->stopped(), "cutout code must stop, throw, return, etc.");
685 }
686
687 //---------------------------PreserveReexecuteState----------------------------
688 PreserveReexecuteState::PreserveReexecuteState(GraphKit* kit) {
689 assert(!kit->stopped(), "must call stopped() before");
690 _kit = kit;
691 _sp = kit->sp();
692 _reexecute = kit->jvms()->_reexecute;
693 }
694 PreserveReexecuteState::~PreserveReexecuteState() {
695 if (_kit->stopped()) return;
696 _kit->jvms()->_reexecute = _reexecute;
697 _kit->set_sp(_sp);
698 }
699
700 //------------------------------clone_map--------------------------------------
701 // Implementation of PreserveJVMState
702 //
703 // Only clone_map(...) here. If this function is only used in the
704 // PreserveJVMState class we may want to get rid of this extra
705 // function eventually and do it all there.
706
707 SafePointNode* GraphKit::clone_map() {
708 if (map() == NULL) return NULL;
709
710 // Clone the memory edge first
711 Node* mem = MergeMemNode::make(C, map()->memory());
712 gvn().set_type_bottom(mem);
713
714 SafePointNode *clonemap = (SafePointNode*)map()->clone();
715 JVMState* jvms = this->jvms();
716 JVMState* clonejvms = jvms->clone_shallow(C);
717 clonemap->set_memory(mem);
718 clonemap->set_jvms(clonejvms);
719 clonejvms->set_map(clonemap);
720 record_for_igvn(clonemap);
721 gvn().set_type_bottom(clonemap);
722 return clonemap;
723 }
724
725
726 //-----------------------------set_map_clone-----------------------------------
727 void GraphKit::set_map_clone(SafePointNode* m) {
728 _map = m;
729 _map = clone_map();
730 _map->set_next_exception(NULL);
731 debug_only(verify_map());
732 }
733
734
735 //----------------------------kill_dead_locals---------------------------------
736 // Detect any locals which are known to be dead, and force them to top.
737 void GraphKit::kill_dead_locals() {
738 // Consult the liveness information for the locals. If any
739 // of them are unused, then they can be replaced by top(). This
740 // should help register allocation time and cut down on the size
741 // of the deoptimization information.
742
743 // This call is made from many of the bytecode handling
744 // subroutines called from the Big Switch in do_one_bytecode.
745 // Every bytecode which might include a slow path is responsible
746 // for killing its dead locals. The more consistent we
747 // are about killing deads, the fewer useless phis will be
748 // constructed for them at various merge points.
749
750 // bci can be -1 (InvocationEntryBci). We return the entry
751 // liveness for the method.
752
753 if (method() == NULL || method()->code_size() == 0) {
754 // We are building a graph for a call to a native method.
755 // All locals are live.
756 return;
757 }
758
759 ResourceMark rm;
760
761 // Consult the liveness information for the locals. If any
762 // of them are unused, then they can be replaced by top(). This
763 // should help register allocation time and cut down on the size
764 // of the deoptimization information.
765 MethodLivenessResult live_locals = method()->liveness_at_bci(bci());
766
767 int len = (int)live_locals.size();
768 assert(len <= jvms()->loc_size(), "too many live locals");
769 for (int local = 0; local < len; local++) {
770 if (!live_locals.at(local)) {
771 set_local(local, top());
772 }
773 }
774 }
775
776 #ifdef ASSERT
777 //-------------------------dead_locals_are_killed------------------------------
778 // Return true if all dead locals are set to top in the map.
779 // Used to assert "clean" debug info at various points.
780 bool GraphKit::dead_locals_are_killed() {
781 if (method() == NULL || method()->code_size() == 0) {
782 // No locals need to be dead, so all is as it should be.
783 return true;
784 }
785
786 // Make sure somebody called kill_dead_locals upstream.
787 ResourceMark rm;
788 for (JVMState* jvms = this->jvms(); jvms != NULL; jvms = jvms->caller()) {
789 if (jvms->loc_size() == 0) continue; // no locals to consult
790 SafePointNode* map = jvms->map();
791 ciMethod* method = jvms->method();
792 int bci = jvms->bci();
793 if (jvms == this->jvms()) {
794 bci = this->bci(); // it might not yet be synched
795 }
796 MethodLivenessResult live_locals = method->liveness_at_bci(bci);
797 int len = (int)live_locals.size();
798 if (!live_locals.is_valid() || len == 0)
799 // This method is trivial, or is poisoned by a breakpoint.
800 return true;
801 assert(len == jvms->loc_size(), "live map consistent with locals map");
802 for (int local = 0; local < len; local++) {
803 if (!live_locals.at(local) && map->local(jvms, local) != top()) {
804 if (PrintMiscellaneous && (Verbose || WizardMode)) {
805 tty->print_cr("Zombie local %d: ", local);
806 jvms->dump();
807 }
808 return false;
809 }
810 }
811 }
812 return true;
813 }
814
815 #endif //ASSERT
816
817 // Helper function for enforcing certain bytecodes to reexecute if
818 // deoptimization happens
819 static bool should_reexecute_implied_by_bytecode(JVMState *jvms, bool is_anewarray) {
820 ciMethod* cur_method = jvms->method();
821 int cur_bci = jvms->bci();
822 if (cur_method != NULL && cur_bci != InvocationEntryBci) {
823 Bytecodes::Code code = cur_method->java_code_at_bci(cur_bci);
824 return Interpreter::bytecode_should_reexecute(code) ||
825 is_anewarray && code == Bytecodes::_multianewarray;
826 // Reexecute _multianewarray bytecode which was replaced with
827 // sequence of [a]newarray. See Parse::do_multianewarray().
828 //
829 // Note: interpreter should not have it set since this optimization
830 // is limited by dimensions and guarded by flag so in some cases
831 // multianewarray() runtime calls will be generated and
832 // the bytecode should not be reexecutes (stack will not be reset).
833 } else
834 return false;
835 }
836
837 // Helper function for adding JVMState and debug information to node
838 void GraphKit::add_safepoint_edges(SafePointNode* call, bool must_throw) {
839 // Add the safepoint edges to the call (or other safepoint).
840
841 // Make sure dead locals are set to top. This
842 // should help register allocation time and cut down on the size
843 // of the deoptimization information.
844 assert(dead_locals_are_killed(), "garbage in debug info before safepoint");
845
846 // Walk the inline list to fill in the correct set of JVMState's
847 // Also fill in the associated edges for each JVMState.
848
849 // If the bytecode needs to be reexecuted we need to put
850 // the arguments back on the stack.
851 const bool should_reexecute = jvms()->should_reexecute();
852 JVMState* youngest_jvms = should_reexecute ? sync_jvms_for_reexecute() : sync_jvms();
853
854 // NOTE: set_bci (called from sync_jvms) might reset the reexecute bit to
855 // undefined if the bci is different. This is normal for Parse but it
856 // should not happen for LibraryCallKit because only one bci is processed.
857 assert(!is_LibraryCallKit() || (jvms()->should_reexecute() == should_reexecute),
858 "in LibraryCallKit the reexecute bit should not change");
859
860 // If we are guaranteed to throw, we can prune everything but the
861 // input to the current bytecode.
862 bool can_prune_locals = false;
863 uint stack_slots_not_pruned = 0;
864 int inputs = 0, depth = 0;
865 if (must_throw) {
866 assert(method() == youngest_jvms->method(), "sanity");
867 if (compute_stack_effects(inputs, depth)) {
868 can_prune_locals = true;
869 stack_slots_not_pruned = inputs;
870 }
871 }
872
873 if (env()->should_retain_local_variables()) {
874 // At any safepoint, this method can get breakpointed, which would
875 // then require an immediate deoptimization.
876 can_prune_locals = false; // do not prune locals
877 stack_slots_not_pruned = 0;
878 }
879
880 // do not scribble on the input jvms
881 JVMState* out_jvms = youngest_jvms->clone_deep(C);
882 call->set_jvms(out_jvms); // Start jvms list for call node
883
884 // For a known set of bytecodes, the interpreter should reexecute them if
885 // deoptimization happens. We set the reexecute state for them here
886 if (out_jvms->is_reexecute_undefined() && //don't change if already specified
887 should_reexecute_implied_by_bytecode(out_jvms, call->is_AllocateArray())) {
888 out_jvms->set_should_reexecute(true); //NOTE: youngest_jvms not changed
889 }
890
891 // Presize the call:
892 DEBUG_ONLY(uint non_debug_edges = call->req());
893 call->add_req_batch(top(), youngest_jvms->debug_depth());
894 assert(call->req() == non_debug_edges + youngest_jvms->debug_depth(), "");
895
896 // Set up edges so that the call looks like this:
897 // Call [state:] ctl io mem fptr retadr
898 // [parms:] parm0 ... parmN
899 // [root:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
900 // [...mid:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN [...]
901 // [young:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
902 // Note that caller debug info precedes callee debug info.
903
904 // Fill pointer walks backwards from "young:" to "root:" in the diagram above:
905 uint debug_ptr = call->req();
906
907 // Loop over the map input edges associated with jvms, add them
908 // to the call node, & reset all offsets to match call node array.
909 for (JVMState* in_jvms = youngest_jvms; in_jvms != NULL; ) {
910 uint debug_end = debug_ptr;
911 uint debug_start = debug_ptr - in_jvms->debug_size();
912 debug_ptr = debug_start; // back up the ptr
913
914 uint p = debug_start; // walks forward in [debug_start, debug_end)
915 uint j, k, l;
916 SafePointNode* in_map = in_jvms->map();
917 out_jvms->set_map(call);
918
919 if (can_prune_locals) {
920 assert(in_jvms->method() == out_jvms->method(), "sanity");
921 // If the current throw can reach an exception handler in this JVMS,
922 // then we must keep everything live that can reach that handler.
923 // As a quick and dirty approximation, we look for any handlers at all.
924 if (in_jvms->method()->has_exception_handlers()) {
925 can_prune_locals = false;
926 }
927 }
928
929 // Add the Locals
930 k = in_jvms->locoff();
931 l = in_jvms->loc_size();
932 out_jvms->set_locoff(p);
933 if (!can_prune_locals) {
934 for (j = 0; j < l; j++)
935 call->set_req(p++, in_map->in(k+j));
936 } else {
937 p += l; // already set to top above by add_req_batch
938 }
939
940 // Add the Expression Stack
941 k = in_jvms->stkoff();
942 l = in_jvms->sp();
943 out_jvms->set_stkoff(p);
944 if (!can_prune_locals) {
945 for (j = 0; j < l; j++)
946 call->set_req(p++, in_map->in(k+j));
947 } else if (can_prune_locals && stack_slots_not_pruned != 0) {
948 // Divide stack into {S0,...,S1}, where S0 is set to top.
949 uint s1 = stack_slots_not_pruned;
950 stack_slots_not_pruned = 0; // for next iteration
951 if (s1 > l) s1 = l;
952 uint s0 = l - s1;
953 p += s0; // skip the tops preinstalled by add_req_batch
954 for (j = s0; j < l; j++)
955 call->set_req(p++, in_map->in(k+j));
956 } else {
957 p += l; // already set to top above by add_req_batch
958 }
959
960 // Add the Monitors
961 k = in_jvms->monoff();
962 l = in_jvms->mon_size();
963 out_jvms->set_monoff(p);
964 for (j = 0; j < l; j++)
965 call->set_req(p++, in_map->in(k+j));
966
967 // Copy any scalar object fields.
968 k = in_jvms->scloff();
969 l = in_jvms->scl_size();
970 out_jvms->set_scloff(p);
971 for (j = 0; j < l; j++)
972 call->set_req(p++, in_map->in(k+j));
973
974 // Finish the new jvms.
975 out_jvms->set_endoff(p);
976
977 assert(out_jvms->endoff() == debug_end, "fill ptr must match");
978 assert(out_jvms->depth() == in_jvms->depth(), "depth must match");
979 assert(out_jvms->loc_size() == in_jvms->loc_size(), "size must match");
980 assert(out_jvms->mon_size() == in_jvms->mon_size(), "size must match");
981 assert(out_jvms->scl_size() == in_jvms->scl_size(), "size must match");
982 assert(out_jvms->debug_size() == in_jvms->debug_size(), "size must match");
983
984 // Update the two tail pointers in parallel.
985 out_jvms = out_jvms->caller();
986 in_jvms = in_jvms->caller();
987 }
988
989 assert(debug_ptr == non_debug_edges, "debug info must fit exactly");
990
991 // Test the correctness of JVMState::debug_xxx accessors:
992 assert(call->jvms()->debug_start() == non_debug_edges, "");
993 assert(call->jvms()->debug_end() == call->req(), "");
994 assert(call->jvms()->debug_depth() == call->req() - non_debug_edges, "");
995 }
996
997 bool GraphKit::compute_stack_effects(int& inputs, int& depth) {
998 Bytecodes::Code code = java_bc();
999 if (code == Bytecodes::_wide) {
1000 code = method()->java_code_at_bci(bci() + 1);
1001 }
1002
1003 BasicType rtype = T_ILLEGAL;
1004 int rsize = 0;
1005
1006 if (code != Bytecodes::_illegal) {
1007 depth = Bytecodes::depth(code); // checkcast=0, athrow=-1
1008 rtype = Bytecodes::result_type(code); // checkcast=P, athrow=V
1009 if (rtype < T_CONFLICT)
1010 rsize = type2size[rtype];
1011 }
1012
1013 switch (code) {
1014 case Bytecodes::_illegal:
1015 return false;
1016
1017 case Bytecodes::_ldc:
1018 case Bytecodes::_ldc_w:
1019 case Bytecodes::_ldc2_w:
1020 inputs = 0;
1021 break;
1022
1023 case Bytecodes::_dup: inputs = 1; break;
1024 case Bytecodes::_dup_x1: inputs = 2; break;
1025 case Bytecodes::_dup_x2: inputs = 3; break;
1026 case Bytecodes::_dup2: inputs = 2; break;
1027 case Bytecodes::_dup2_x1: inputs = 3; break;
1028 case Bytecodes::_dup2_x2: inputs = 4; break;
1029 case Bytecodes::_swap: inputs = 2; break;
1030 case Bytecodes::_arraylength: inputs = 1; break;
1031
1032 case Bytecodes::_getstatic:
1033 case Bytecodes::_putstatic:
1034 case Bytecodes::_getfield:
1035 case Bytecodes::_putfield:
1036 {
1037 bool ignored_will_link;
1038 ciField* field = method()->get_field_at_bci(bci(), ignored_will_link);
1039 int size = field->type()->size();
1040 bool is_get = (depth >= 0), is_static = (depth & 1);
1041 inputs = (is_static ? 0 : 1);
1042 if (is_get) {
1043 depth = size - inputs;
1044 } else {
1045 inputs += size; // putxxx pops the value from the stack
1046 depth = - inputs;
1047 }
1048 }
1049 break;
1050
1051 case Bytecodes::_invokevirtual:
1052 case Bytecodes::_invokespecial:
1053 case Bytecodes::_invokestatic:
1054 case Bytecodes::_invokedynamic:
1055 case Bytecodes::_invokeinterface:
1056 {
1057 bool ignored_will_link;
1058 ciSignature* declared_signature = NULL;
1059 ciMethod* ignored_callee = method()->get_method_at_bci(bci(), ignored_will_link, &declared_signature);
1060 assert(declared_signature != NULL, "cannot be null");
1061 inputs = declared_signature->arg_size_for_bc(code);
1062 int size = declared_signature->return_type()->size();
1063 depth = size - inputs;
1064 }
1065 break;
1066
1067 case Bytecodes::_multianewarray:
1068 {
1069 ciBytecodeStream iter(method());
1070 iter.reset_to_bci(bci());
1071 iter.next();
1072 inputs = iter.get_dimensions();
1073 assert(rsize == 1, "");
1074 depth = rsize - inputs;
1075 }
1076 break;
1077
1078 case Bytecodes::_ireturn:
1079 case Bytecodes::_lreturn:
1080 case Bytecodes::_freturn:
1081 case Bytecodes::_dreturn:
1082 case Bytecodes::_areturn:
1083 assert(rsize = -depth, "");
1084 inputs = rsize;
1085 break;
1086
1087 case Bytecodes::_jsr:
1088 case Bytecodes::_jsr_w:
1089 inputs = 0;
1090 depth = 1; // S.B. depth=1, not zero
1091 break;
1092
1093 default:
1094 // bytecode produces a typed result
1095 inputs = rsize - depth;
1096 assert(inputs >= 0, "");
1097 break;
1098 }
1099
1100 #ifdef ASSERT
1101 // spot check
1102 int outputs = depth + inputs;
1103 assert(outputs >= 0, "sanity");
1104 switch (code) {
1105 case Bytecodes::_checkcast: assert(inputs == 1 && outputs == 1, ""); break;
1106 case Bytecodes::_athrow: assert(inputs == 1 && outputs == 0, ""); break;
1107 case Bytecodes::_aload_0: assert(inputs == 0 && outputs == 1, ""); break;
1108 case Bytecodes::_return: assert(inputs == 0 && outputs == 0, ""); break;
1109 case Bytecodes::_drem: assert(inputs == 4 && outputs == 2, ""); break;
1110 }
1111 #endif //ASSERT
1112
1113 return true;
1114 }
1115
1116
1117
1118 //------------------------------basic_plus_adr---------------------------------
1119 Node* GraphKit::basic_plus_adr(Node* base, Node* ptr, Node* offset) {
1120 // short-circuit a common case
1121 if (offset == intcon(0)) return ptr;
1122 return _gvn.transform( new (C) AddPNode(base, ptr, offset) );
1123 }
1124
1125 Node* GraphKit::ConvI2L(Node* offset) {
1126 // short-circuit a common case
1127 jint offset_con = find_int_con(offset, Type::OffsetBot);
1128 if (offset_con != Type::OffsetBot) {
1129 return longcon((jlong) offset_con);
1130 }
1131 return _gvn.transform( new (C) ConvI2LNode(offset));
1132 }
1133 Node* GraphKit::ConvL2I(Node* offset) {
1134 // short-circuit a common case
1135 jlong offset_con = find_long_con(offset, (jlong)Type::OffsetBot);
1136 if (offset_con != (jlong)Type::OffsetBot) {
1137 return intcon((int) offset_con);
1138 }
1139 return _gvn.transform( new (C) ConvL2INode(offset));
1140 }
1141
1142 //-------------------------load_object_klass-----------------------------------
1143 Node* GraphKit::load_object_klass(Node* obj) {
1144 // Special-case a fresh allocation to avoid building nodes:
1145 Node* akls = AllocateNode::Ideal_klass(obj, &_gvn);
1146 if (akls != NULL) return akls;
1147 Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes());
1148 return _gvn.transform( LoadKlassNode::make(_gvn, immutable_memory(), k_adr, TypeInstPtr::KLASS) );
1149 }
1150
1151 //-------------------------load_array_length-----------------------------------
1152 Node* GraphKit::load_array_length(Node* array) {
1153 // Special-case a fresh allocation to avoid building nodes:
1154 AllocateArrayNode* alloc = AllocateArrayNode::Ideal_array_allocation(array, &_gvn);
1155 Node *alen;
1156 if (alloc == NULL) {
1157 Node *r_adr = basic_plus_adr(array, arrayOopDesc::length_offset_in_bytes());
1158 alen = _gvn.transform( new (C) LoadRangeNode(0, immutable_memory(), r_adr, TypeInt::POS));
1159 } else {
1160 alen = alloc->Ideal_length();
1161 Node* ccast = alloc->make_ideal_length(_gvn.type(array)->is_oopptr(), &_gvn);
1162 if (ccast != alen) {
1163 alen = _gvn.transform(ccast);
1164 }
1165 }
1166 return alen;
1167 }
1168
1169 //------------------------------do_null_check----------------------------------
1170 // Helper function to do a NULL pointer check. Returned value is
1171 // the incoming address with NULL casted away. You are allowed to use the
1172 // not-null value only if you are control dependent on the test.
1173 extern int explicit_null_checks_inserted,
1174 explicit_null_checks_elided;
1175 Node* GraphKit::null_check_common(Node* value, BasicType type,
1176 // optional arguments for variations:
1177 bool assert_null,
1178 Node* *null_control) {
1179 assert(!assert_null || null_control == NULL, "not both at once");
1180 if (stopped()) return top();
1181 if (!GenerateCompilerNullChecks && !assert_null && null_control == NULL) {
1182 // For some performance testing, we may wish to suppress null checking.
1183 value = cast_not_null(value); // Make it appear to be non-null (4962416).
1184 return value;
1185 }
1186 explicit_null_checks_inserted++;
1187
1188 // Construct NULL check
1189 Node *chk = NULL;
1190 switch(type) {
1191 case T_LONG : chk = new (C) CmpLNode(value, _gvn.zerocon(T_LONG)); break;
1192 case T_INT : chk = new (C) CmpINode(value, _gvn.intcon(0)); break;
1193 case T_ARRAY : // fall through
1194 type = T_OBJECT; // simplify further tests
1195 case T_OBJECT : {
1196 const Type *t = _gvn.type( value );
1197
1198 const TypeOopPtr* tp = t->isa_oopptr();
1199 if (tp != NULL && tp->klass() != NULL && !tp->klass()->is_loaded()
1200 // Only for do_null_check, not any of its siblings:
1201 && !assert_null && null_control == NULL) {
1202 // Usually, any field access or invocation on an unloaded oop type
1203 // will simply fail to link, since the statically linked class is
1204 // likely also to be unloaded. However, in -Xcomp mode, sometimes
1205 // the static class is loaded but the sharper oop type is not.
1206 // Rather than checking for this obscure case in lots of places,
1207 // we simply observe that a null check on an unloaded class
1208 // will always be followed by a nonsense operation, so we
1209 // can just issue the uncommon trap here.
1210 // Our access to the unloaded class will only be correct
1211 // after it has been loaded and initialized, which requires
1212 // a trip through the interpreter.
1213 #ifndef PRODUCT
1214 if (WizardMode) { tty->print("Null check of unloaded "); tp->klass()->print(); tty->cr(); }
1215 #endif
1216 uncommon_trap(Deoptimization::Reason_unloaded,
1217 Deoptimization::Action_reinterpret,
1218 tp->klass(), "!loaded");
1219 return top();
1220 }
1221
1222 if (assert_null) {
1223 // See if the type is contained in NULL_PTR.
1224 // If so, then the value is already null.
1225 if (t->higher_equal(TypePtr::NULL_PTR)) {
1226 explicit_null_checks_elided++;
1227 return value; // Elided null assert quickly!
1228 }
1229 } else {
1230 // See if mixing in the NULL pointer changes type.
1231 // If so, then the NULL pointer was not allowed in the original
1232 // type. In other words, "value" was not-null.
1233 if (t->meet(TypePtr::NULL_PTR) != t->remove_speculative()) {
1234 // same as: if (!TypePtr::NULL_PTR->higher_equal(t)) ...
1235 explicit_null_checks_elided++;
1236 return value; // Elided null check quickly!
1237 }
1238 }
1239 chk = new (C) CmpPNode( value, null() );
1240 break;
1241 }
1242
1243 default:
1244 fatal(err_msg_res("unexpected type: %s", type2name(type)));
1245 }
1246 assert(chk != NULL, "sanity check");
1247 chk = _gvn.transform(chk);
1248
1249 BoolTest::mask btest = assert_null ? BoolTest::eq : BoolTest::ne;
1250 BoolNode *btst = new (C) BoolNode( chk, btest);
1251 Node *tst = _gvn.transform( btst );
1252
1253 //-----------
1254 // if peephole optimizations occurred, a prior test existed.
1255 // If a prior test existed, maybe it dominates as we can avoid this test.
1256 if (tst != btst && type == T_OBJECT) {
1257 // At this point we want to scan up the CFG to see if we can
1258 // find an identical test (and so avoid this test altogether).
1259 Node *cfg = control();
1260 int depth = 0;
1261 while( depth < 16 ) { // Limit search depth for speed
1262 if( cfg->Opcode() == Op_IfTrue &&
1263 cfg->in(0)->in(1) == tst ) {
1264 // Found prior test. Use "cast_not_null" to construct an identical
1265 // CastPP (and hence hash to) as already exists for the prior test.
1266 // Return that casted value.
1267 if (assert_null) {
1268 replace_in_map(value, null());
1269 return null(); // do not issue the redundant test
1270 }
1271 Node *oldcontrol = control();
1272 set_control(cfg);
1273 Node *res = cast_not_null(value);
1274 set_control(oldcontrol);
1275 explicit_null_checks_elided++;
1276 return res;
1277 }
1278 cfg = IfNode::up_one_dom(cfg, /*linear_only=*/ true);
1279 if (cfg == NULL) break; // Quit at region nodes
1280 depth++;
1281 }
1282 }
1283
1284 //-----------
1285 // Branch to failure if null
1286 float ok_prob = PROB_MAX; // a priori estimate: nulls never happen
1287 Deoptimization::DeoptReason reason;
1288 if (assert_null)
1289 reason = Deoptimization::Reason_null_assert;
1290 else if (type == T_OBJECT)
1291 reason = Deoptimization::Reason_null_check;
1292 else
1293 reason = Deoptimization::Reason_div0_check;
1294
1295 // %%% Since Reason_unhandled is not recorded on a per-bytecode basis,
1296 // ciMethodData::has_trap_at will return a conservative -1 if any
1297 // must-be-null assertion has failed. This could cause performance
1298 // problems for a method after its first do_null_assert failure.
1299 // Consider using 'Reason_class_check' instead?
1300
1301 // To cause an implicit null check, we set the not-null probability
1302 // to the maximum (PROB_MAX). For an explicit check the probability
1303 // is set to a smaller value.
1304 if (null_control != NULL || too_many_traps(reason)) {
1305 // probability is less likely
1306 ok_prob = PROB_LIKELY_MAG(3);
1307 } else if (!assert_null &&
1308 (ImplicitNullCheckThreshold > 0) &&
1309 method() != NULL &&
1310 (method()->method_data()->trap_count(reason)
1311 >= (uint)ImplicitNullCheckThreshold)) {
1312 ok_prob = PROB_LIKELY_MAG(3);
1313 }
1314
1315 if (null_control != NULL) {
1316 IfNode* iff = create_and_map_if(control(), tst, ok_prob, COUNT_UNKNOWN);
1317 Node* null_true = _gvn.transform( new (C) IfFalseNode(iff));
1318 set_control( _gvn.transform( new (C) IfTrueNode(iff)));
1319 if (null_true == top())
1320 explicit_null_checks_elided++;
1321 (*null_control) = null_true;
1322 } else {
1323 BuildCutout unless(this, tst, ok_prob);
1324 // Check for optimizer eliding test at parse time
1325 if (stopped()) {
1326 // Failure not possible; do not bother making uncommon trap.
1327 explicit_null_checks_elided++;
1328 } else if (assert_null) {
1329 uncommon_trap(reason,
1330 Deoptimization::Action_make_not_entrant,
1331 NULL, "assert_null");
1332 } else {
1333 replace_in_map(value, zerocon(type));
1334 builtin_throw(reason);
1335 }
1336 }
1337
1338 // Must throw exception, fall-thru not possible?
1339 if (stopped()) {
1340 return top(); // No result
1341 }
1342
1343 if (assert_null) {
1344 // Cast obj to null on this path.
1345 replace_in_map(value, zerocon(type));
1346 return zerocon(type);
1347 }
1348
1349 // Cast obj to not-null on this path, if there is no null_control.
1350 // (If there is a null_control, a non-null value may come back to haunt us.)
1351 if (type == T_OBJECT) {
1352 Node* cast = cast_not_null(value, false);
1353 if (null_control == NULL || (*null_control) == top())
1354 replace_in_map(value, cast);
1355 value = cast;
1356 }
1357
1358 return value;
1359 }
1360
1361
1362 //------------------------------cast_not_null----------------------------------
1363 // Cast obj to not-null on this path
1364 Node* GraphKit::cast_not_null(Node* obj, bool do_replace_in_map) {
1365 const Type *t = _gvn.type(obj);
1366 const Type *t_not_null = t->join_speculative(TypePtr::NOTNULL);
1367 // Object is already not-null?
1368 if( t == t_not_null ) return obj;
1369
1370 Node *cast = new (C) CastPPNode(obj,t_not_null);
1371 cast->init_req(0, control());
1372 cast = _gvn.transform( cast );
1373
1374 // Scan for instances of 'obj' in the current JVM mapping.
1375 // These instances are known to be not-null after the test.
1376 if (do_replace_in_map)
1377 replace_in_map(obj, cast);
1378
1379 return cast; // Return casted value
1380 }
1381
1382
1383 //--------------------------replace_in_map-------------------------------------
1384 void GraphKit::replace_in_map(Node* old, Node* neww) {
1385 if (old == neww) {
1386 return;
1387 }
1388
1389 map()->replace_edge(old, neww);
1390
1391 // Note: This operation potentially replaces any edge
1392 // on the map. This includes locals, stack, and monitors
1393 // of the current (innermost) JVM state.
1394
1395 if (!ReplaceInParentMaps) {
1396 return;
1397 }
1398
1399 // PreserveJVMState doesn't do a deep copy so we can't modify
1400 // parents
1401 if (Compile::current()->has_preserve_jvm_state()) {
1402 return;
1403 }
1404
1405 Parse* parser = is_Parse();
1406 bool progress = true;
1407 Node* ctrl = map()->in(0);
1408 // Follow the chain of parsers and see whether the update can be
1409 // done in the map of callers. We can do the replace for a caller if
1410 // the current control post dominates the control of a caller.
1411 while (parser != NULL && parser->caller() != NULL && progress) {
1412 progress = false;
1413 Node* parent_map = parser->caller()->map();
1414 assert(parser->exits().map()->jvms()->depth() == parser->caller()->depth(), "map mismatch");
1415
1416 Node* parent_ctrl = parent_map->in(0);
1417
1418 while (parent_ctrl->is_Region()) {
1419 Node* n = parent_ctrl->as_Region()->is_copy();
1420 if (n == NULL) {
1421 break;
1422 }
1423 parent_ctrl = n;
1424 }
1425
1426 for (;;) {
1427 if (ctrl == parent_ctrl) {
1428 // update the map of the exits which is the one that will be
1429 // used when compilation resume after inlining
1430 parser->exits().map()->replace_edge(old, neww);
1431 progress = true;
1432 break;
1433 }
1434 if (ctrl->is_Proj() && ctrl->as_Proj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none)) {
1435 ctrl = ctrl->in(0)->in(0);
1436 } else if (ctrl->is_Region()) {
1437 Node* n = ctrl->as_Region()->is_copy();
1438 if (n == NULL) {
1439 break;
1440 }
1441 ctrl = n;
1442 } else {
1443 break;
1444 }
1445 }
1446
1447 parser = parser->parent_parser();
1448 }
1449 }
1450
1451
1452 //=============================================================================
1453 //--------------------------------memory---------------------------------------
1454 Node* GraphKit::memory(uint alias_idx) {
1455 MergeMemNode* mem = merged_memory();
1456 Node* p = mem->memory_at(alias_idx);
1457 _gvn.set_type(p, Type::MEMORY); // must be mapped
1458 return p;
1459 }
1460
1461 //-----------------------------reset_memory------------------------------------
1462 Node* GraphKit::reset_memory() {
1463 Node* mem = map()->memory();
1464 // do not use this node for any more parsing!
1465 debug_only( map()->set_memory((Node*)NULL) );
1466 return _gvn.transform( mem );
1467 }
1468
1469 //------------------------------set_all_memory---------------------------------
1470 void GraphKit::set_all_memory(Node* newmem) {
1471 Node* mergemem = MergeMemNode::make(C, newmem);
1472 gvn().set_type_bottom(mergemem);
1473 map()->set_memory(mergemem);
1474 }
1475
1476 //------------------------------set_all_memory_call----------------------------
1477 void GraphKit::set_all_memory_call(Node* call, bool separate_io_proj) {
1478 Node* newmem = _gvn.transform( new (C) ProjNode(call, TypeFunc::Memory, separate_io_proj) );
1479 set_all_memory(newmem);
1480 }
1481
1482 //=============================================================================
1483 //
1484 // parser factory methods for MemNodes
1485 //
1486 // These are layered on top of the factory methods in LoadNode and StoreNode,
1487 // and integrate with the parser's memory state and _gvn engine.
1488 //
1489
1490 // factory methods in "int adr_idx"
1491 Node* GraphKit::make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
1492 int adr_idx,
1493 MemNode::MemOrd mo, bool require_atomic_access) {
1494 assert(adr_idx != Compile::AliasIdxTop, "use other make_load factory" );
1495 const TypePtr* adr_type = NULL; // debug-mode-only argument
1496 debug_only(adr_type = C->get_adr_type(adr_idx));
1497 Node* mem = memory(adr_idx);
1498 Node* ld;
1499 if (require_atomic_access && bt == T_LONG) {
1500 ld = LoadLNode::make_atomic(C, ctl, mem, adr, adr_type, t, mo);
1501 } else {
1502 ld = LoadNode::make(_gvn, ctl, mem, adr, adr_type, t, bt, mo);
1503 }
1504 ld = _gvn.transform(ld);
1505 if ((bt == T_OBJECT) && C->do_escape_analysis() || C->eliminate_boxing()) {
1506 // Improve graph before escape analysis and boxing elimination.
1507 record_for_igvn(ld);
1508 }
1509 return ld;
1510 }
1511
1512 Node* GraphKit::store_to_memory(Node* ctl, Node* adr, Node *val, BasicType bt,
1513 int adr_idx,
1514 MemNode::MemOrd mo,
1515 bool require_atomic_access) {
1516 assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1517 const TypePtr* adr_type = NULL;
1518 debug_only(adr_type = C->get_adr_type(adr_idx));
1519 Node *mem = memory(adr_idx);
1520 Node* st;
1521 if (require_atomic_access && bt == T_LONG) {
1522 st = StoreLNode::make_atomic(C, ctl, mem, adr, adr_type, val, mo);
1523 } else {
1524 st = StoreNode::make(_gvn, ctl, mem, adr, adr_type, val, bt, mo);
1525 }
1526 st = _gvn.transform(st);
1527 set_memory(st, adr_idx);
1528 // Back-to-back stores can only remove intermediate store with DU info
1529 // so push on worklist for optimizer.
1530 if (mem->req() > MemNode::Address && adr == mem->in(MemNode::Address))
1531 record_for_igvn(st);
1532
1533 return st;
1534 }
1535
1536
1537 void GraphKit::pre_barrier(bool do_load,
1538 Node* ctl,
1539 Node* obj,
1540 Node* adr,
1541 uint adr_idx,
1542 Node* val,
1543 const TypeOopPtr* val_type,
1544 Node* pre_val,
1545 BasicType bt) {
1546
1547 BarrierSet* bs = Universe::heap()->barrier_set();
1548 set_control(ctl);
1549 switch (bs->kind()) {
1550 case BarrierSet::G1SATBCT:
1551 case BarrierSet::G1SATBCTLogging:
1552 g1_write_barrier_pre(do_load, obj, adr, adr_idx, val, val_type, pre_val, bt);
1553 break;
1554
1555 case BarrierSet::CardTableModRef:
1556 case BarrierSet::CardTableExtension:
1557 case BarrierSet::ModRef:
1558 break;
1559
1560 case BarrierSet::Other:
1561 default :
1562 ShouldNotReachHere();
1563
1564 }
1565 }
1566
1567 bool GraphKit::can_move_pre_barrier() const {
1568 BarrierSet* bs = Universe::heap()->barrier_set();
1569 switch (bs->kind()) {
1570 case BarrierSet::G1SATBCT:
1571 case BarrierSet::G1SATBCTLogging:
1572 return true; // Can move it if no safepoint
1573
1574 case BarrierSet::CardTableModRef:
1575 case BarrierSet::CardTableExtension:
1576 case BarrierSet::ModRef:
1577 return true; // There is no pre-barrier
1578
1579 case BarrierSet::Other:
1580 default :
1581 ShouldNotReachHere();
1582 }
1583 return false;
1584 }
1585
1586 void GraphKit::post_barrier(Node* ctl,
1587 Node* store,
1588 Node* obj,
1589 Node* adr,
1590 uint adr_idx,
1591 Node* val,
1592 BasicType bt,
1593 bool use_precise) {
1594 BarrierSet* bs = Universe::heap()->barrier_set();
1595 set_control(ctl);
1596 switch (bs->kind()) {
1597 case BarrierSet::G1SATBCT:
1598 case BarrierSet::G1SATBCTLogging:
1599 g1_write_barrier_post(store, obj, adr, adr_idx, val, bt, use_precise);
1600 break;
1601
1602 case BarrierSet::CardTableModRef:
1603 case BarrierSet::CardTableExtension:
1604 write_barrier_post(store, obj, adr, adr_idx, val, use_precise);
1605 break;
1606
1607 case BarrierSet::ModRef:
1608 break;
1609
1610 case BarrierSet::Other:
1611 default :
1612 ShouldNotReachHere();
1613
1614 }
1615 }
1616
1617 Node* GraphKit::store_oop(Node* ctl,
1618 Node* obj,
1619 Node* adr,
1620 const TypePtr* adr_type,
1621 Node* val,
1622 const TypeOopPtr* val_type,
1623 BasicType bt,
1624 bool use_precise,
1625 MemNode::MemOrd mo) {
1626 // Transformation of a value which could be NULL pointer (CastPP #NULL)
1627 // could be delayed during Parse (for example, in adjust_map_after_if()).
1628 // Execute transformation here to avoid barrier generation in such case.
1629 if (_gvn.type(val) == TypePtr::NULL_PTR)
1630 val = _gvn.makecon(TypePtr::NULL_PTR);
1631
1632 set_control(ctl);
1633 if (stopped()) return top(); // Dead path ?
1634
1635 assert(bt == T_OBJECT, "sanity");
1636 assert(val != NULL, "not dead path");
1637 uint adr_idx = C->get_alias_index(adr_type);
1638 assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1639
1640 pre_barrier(true /* do_load */,
1641 control(), obj, adr, adr_idx, val, val_type,
1642 NULL /* pre_val */,
1643 bt);
1644
1645 Node* store = store_to_memory(control(), adr, val, bt, adr_idx, mo);
1646 post_barrier(control(), store, obj, adr, adr_idx, val, bt, use_precise);
1647 return store;
1648 }
1649
1650 // Could be an array or object we don't know at compile time (unsafe ref.)
1651 Node* GraphKit::store_oop_to_unknown(Node* ctl,
1652 Node* obj, // containing obj
1653 Node* adr, // actual adress to store val at
1654 const TypePtr* adr_type,
1655 Node* val,
1656 BasicType bt,
1657 MemNode::MemOrd mo) {
1658 Compile::AliasType* at = C->alias_type(adr_type);
1659 const TypeOopPtr* val_type = NULL;
1660 if (adr_type->isa_instptr()) {
1661 if (at->field() != NULL) {
1662 // known field. This code is a copy of the do_put_xxx logic.
1663 ciField* field = at->field();
1664 if (!field->type()->is_loaded()) {
1665 val_type = TypeInstPtr::BOTTOM;
1666 } else {
1667 val_type = TypeOopPtr::make_from_klass(field->type()->as_klass());
1668 }
1669 }
1670 } else if (adr_type->isa_aryptr()) {
1671 val_type = adr_type->is_aryptr()->elem()->make_oopptr();
1672 }
1673 if (val_type == NULL) {
1674 val_type = TypeInstPtr::BOTTOM;
1675 }
1676 return store_oop(ctl, obj, adr, adr_type, val, val_type, bt, true, mo);
1677 }
1678
1679
1680 //-------------------------array_element_address-------------------------
1681 Node* GraphKit::array_element_address(Node* ary, Node* idx, BasicType elembt,
1682 const TypeInt* sizetype) {
1683 uint shift = exact_log2(type2aelembytes(elembt));
1684 uint header = arrayOopDesc::base_offset_in_bytes(elembt);
1685
1686 // short-circuit a common case (saves lots of confusing waste motion)
1687 jint idx_con = find_int_con(idx, -1);
1688 if (idx_con >= 0) {
1689 intptr_t offset = header + ((intptr_t)idx_con << shift);
1690 return basic_plus_adr(ary, offset);
1691 }
1692
1693 // must be correct type for alignment purposes
1694 Node* base = basic_plus_adr(ary, header);
1695 #ifdef _LP64
1696 // The scaled index operand to AddP must be a clean 64-bit value.
1697 // Java allows a 32-bit int to be incremented to a negative
1698 // value, which appears in a 64-bit register as a large
1699 // positive number. Using that large positive number as an
1700 // operand in pointer arithmetic has bad consequences.
1701 // On the other hand, 32-bit overflow is rare, and the possibility
1702 // can often be excluded, if we annotate the ConvI2L node with
1703 // a type assertion that its value is known to be a small positive
1704 // number. (The prior range check has ensured this.)
1705 // This assertion is used by ConvI2LNode::Ideal.
1706 int index_max = max_jint - 1; // array size is max_jint, index is one less
1707 if (sizetype != NULL) index_max = sizetype->_hi - 1;
1708 const TypeLong* lidxtype = TypeLong::make(CONST64(0), index_max, Type::WidenMax);
1709 idx = _gvn.transform( new (C) ConvI2LNode(idx, lidxtype) );
1710 #endif
1711 Node* scale = _gvn.transform( new (C) LShiftXNode(idx, intcon(shift)) );
1712 return basic_plus_adr(ary, base, scale);
1713 }
1714
1715 //-------------------------load_array_element-------------------------
1716 Node* GraphKit::load_array_element(Node* ctl, Node* ary, Node* idx, const TypeAryPtr* arytype) {
1717 const Type* elemtype = arytype->elem();
1718 BasicType elembt = elemtype->array_element_basic_type();
1719 Node* adr = array_element_address(ary, idx, elembt, arytype->size());
1720 Node* ld = make_load(ctl, adr, elemtype, elembt, arytype, MemNode::unordered);
1721 return ld;
1722 }
1723
1724 //-------------------------set_arguments_for_java_call-------------------------
1725 // Arguments (pre-popped from the stack) are taken from the JVMS.
1726 void GraphKit::set_arguments_for_java_call(CallJavaNode* call) {
1727 // Add the call arguments:
1728 uint nargs = call->method()->arg_size();
1729 for (uint i = 0; i < nargs; i++) {
1730 Node* arg = argument(i);
1731 call->init_req(i + TypeFunc::Parms, arg);
1732 }
1733 }
1734
1735 //---------------------------set_edges_for_java_call---------------------------
1736 // Connect a newly created call into the current JVMS.
1737 // A return value node (if any) is returned from set_edges_for_java_call.
1738 void GraphKit::set_edges_for_java_call(CallJavaNode* call, bool must_throw, bool separate_io_proj) {
1739
1740 // Add the predefined inputs:
1741 call->init_req( TypeFunc::Control, control() );
1742 call->init_req( TypeFunc::I_O , i_o() );
1743 call->init_req( TypeFunc::Memory , reset_memory() );
1744 call->init_req( TypeFunc::FramePtr, frameptr() );
1745 call->init_req( TypeFunc::ReturnAdr, top() );
1746
1747 add_safepoint_edges(call, must_throw);
1748
1749 Node* xcall = _gvn.transform(call);
1750
1751 if (xcall == top()) {
1752 set_control(top());
1753 return;
1754 }
1755 assert(xcall == call, "call identity is stable");
1756
1757 // Re-use the current map to produce the result.
1758
1759 set_control(_gvn.transform(new (C) ProjNode(call, TypeFunc::Control)));
1760 set_i_o( _gvn.transform(new (C) ProjNode(call, TypeFunc::I_O , separate_io_proj)));
1761 set_all_memory_call(xcall, separate_io_proj);
1762
1763 //return xcall; // no need, caller already has it
1764 }
1765
1766 Node* GraphKit::set_results_for_java_call(CallJavaNode* call, bool separate_io_proj) {
1767 if (stopped()) return top(); // maybe the call folded up?
1768
1769 // Capture the return value, if any.
1770 Node* ret;
1771 if (call->method() == NULL ||
1772 call->method()->return_type()->basic_type() == T_VOID)
1773 ret = top();
1774 else ret = _gvn.transform(new (C) ProjNode(call, TypeFunc::Parms));
1775
1776 // Note: Since any out-of-line call can produce an exception,
1777 // we always insert an I_O projection from the call into the result.
1778
1779 make_slow_call_ex(call, env()->Throwable_klass(), separate_io_proj);
1780
1781 if (separate_io_proj) {
1782 // The caller requested separate projections be used by the fall
1783 // through and exceptional paths, so replace the projections for
1784 // the fall through path.
1785 set_i_o(_gvn.transform( new (C) ProjNode(call, TypeFunc::I_O) ));
1786 set_all_memory(_gvn.transform( new (C) ProjNode(call, TypeFunc::Memory) ));
1787 }
1788 return ret;
1789 }
1790
1791 //--------------------set_predefined_input_for_runtime_call--------------------
1792 // Reading and setting the memory state is way conservative here.
1793 // The real problem is that I am not doing real Type analysis on memory,
1794 // so I cannot distinguish card mark stores from other stores. Across a GC
1795 // point the Store Barrier and the card mark memory has to agree. I cannot
1796 // have a card mark store and its barrier split across the GC point from
1797 // either above or below. Here I get that to happen by reading ALL of memory.
1798 // A better answer would be to separate out card marks from other memory.
1799 // For now, return the input memory state, so that it can be reused
1800 // after the call, if this call has restricted memory effects.
1801 Node* GraphKit::set_predefined_input_for_runtime_call(SafePointNode* call) {
1802 // Set fixed predefined input arguments
1803 Node* memory = reset_memory();
1804 call->init_req( TypeFunc::Control, control() );
1805 call->init_req( TypeFunc::I_O, top() ); // does no i/o
1806 call->init_req( TypeFunc::Memory, memory ); // may gc ptrs
1807 call->init_req( TypeFunc::FramePtr, frameptr() );
1808 call->init_req( TypeFunc::ReturnAdr, top() );
1809 return memory;
1810 }
1811
1812 //-------------------set_predefined_output_for_runtime_call--------------------
1813 // Set control and memory (not i_o) from the call.
1814 // If keep_mem is not NULL, use it for the output state,
1815 // except for the RawPtr output of the call, if hook_mem is TypeRawPtr::BOTTOM.
1816 // If hook_mem is NULL, this call produces no memory effects at all.
1817 // If hook_mem is a Java-visible memory slice (such as arraycopy operands),
1818 // then only that memory slice is taken from the call.
1819 // In the last case, we must put an appropriate memory barrier before
1820 // the call, so as to create the correct anti-dependencies on loads
1821 // preceding the call.
1822 void GraphKit::set_predefined_output_for_runtime_call(Node* call,
1823 Node* keep_mem,
1824 const TypePtr* hook_mem) {
1825 // no i/o
1826 set_control(_gvn.transform( new (C) ProjNode(call,TypeFunc::Control) ));
1827 if (keep_mem) {
1828 // First clone the existing memory state
1829 set_all_memory(keep_mem);
1830 if (hook_mem != NULL) {
1831 // Make memory for the call
1832 Node* mem = _gvn.transform( new (C) ProjNode(call, TypeFunc::Memory) );
1833 // Set the RawPtr memory state only. This covers all the heap top/GC stuff
1834 // We also use hook_mem to extract specific effects from arraycopy stubs.
1835 set_memory(mem, hook_mem);
1836 }
1837 // ...else the call has NO memory effects.
1838
1839 // Make sure the call advertises its memory effects precisely.
1840 // This lets us build accurate anti-dependences in gcm.cpp.
1841 assert(C->alias_type(call->adr_type()) == C->alias_type(hook_mem),
1842 "call node must be constructed correctly");
1843 } else {
1844 assert(hook_mem == NULL, "");
1845 // This is not a "slow path" call; all memory comes from the call.
1846 set_all_memory_call(call);
1847 }
1848 }
1849
1850
1851 // Replace the call with the current state of the kit.
1852 void GraphKit::replace_call(CallNode* call, Node* result) {
1853 JVMState* ejvms = NULL;
1854 if (has_exceptions()) {
1855 ejvms = transfer_exceptions_into_jvms();
1856 }
1857
1858 SafePointNode* final_state = stop();
1859
1860 // Find all the needed outputs of this call
1861 CallProjections callprojs;
1862 call->extract_projections(&callprojs, true);
1863
1864 Node* init_mem = call->in(TypeFunc::Memory);
1865 Node* final_mem = final_state->in(TypeFunc::Memory);
1866 Node* final_ctl = final_state->in(TypeFunc::Control);
1867 Node* final_io = final_state->in(TypeFunc::I_O);
1868
1869 // Replace all the old call edges with the edges from the inlining result
1870 if (callprojs.fallthrough_catchproj != NULL) {
1871 C->gvn_replace_by(callprojs.fallthrough_catchproj, final_ctl);
1872 }
1873 if (callprojs.fallthrough_memproj != NULL) {
1874 C->gvn_replace_by(callprojs.fallthrough_memproj, final_mem);
1875 }
1876 if (callprojs.fallthrough_ioproj != NULL) {
1877 C->gvn_replace_by(callprojs.fallthrough_ioproj, final_io);
1878 }
1879
1880 // Replace the result with the new result if it exists and is used
1881 if (callprojs.resproj != NULL && result != NULL) {
1882 C->gvn_replace_by(callprojs.resproj, result);
1883 }
1884
1885 if (ejvms == NULL) {
1886 // No exception edges to simply kill off those paths
1887 if (callprojs.catchall_catchproj != NULL) {
1888 C->gvn_replace_by(callprojs.catchall_catchproj, C->top());
1889 }
1890 if (callprojs.catchall_memproj != NULL) {
1891 C->gvn_replace_by(callprojs.catchall_memproj, C->top());
1892 }
1893 if (callprojs.catchall_ioproj != NULL) {
1894 C->gvn_replace_by(callprojs.catchall_ioproj, C->top());
1895 }
1896 // Replace the old exception object with top
1897 if (callprojs.exobj != NULL) {
1898 C->gvn_replace_by(callprojs.exobj, C->top());
1899 }
1900 } else {
1901 GraphKit ekit(ejvms);
1902
1903 // Load my combined exception state into the kit, with all phis transformed:
1904 SafePointNode* ex_map = ekit.combine_and_pop_all_exception_states();
1905
1906 Node* ex_oop = ekit.use_exception_state(ex_map);
1907 if (callprojs.catchall_catchproj != NULL) {
1908 C->gvn_replace_by(callprojs.catchall_catchproj, ekit.control());
1909 }
1910 if (callprojs.catchall_memproj != NULL) {
1911 C->gvn_replace_by(callprojs.catchall_memproj, ekit.reset_memory());
1912 }
1913 if (callprojs.catchall_ioproj != NULL) {
1914 C->gvn_replace_by(callprojs.catchall_ioproj, ekit.i_o());
1915 }
1916
1917 // Replace the old exception object with the newly created one
1918 if (callprojs.exobj != NULL) {
1919 C->gvn_replace_by(callprojs.exobj, ex_oop);
1920 }
1921 }
1922
1923 // Disconnect the call from the graph
1924 call->disconnect_inputs(NULL, C);
1925 C->gvn_replace_by(call, C->top());
1926
1927 // Clean up any MergeMems that feed other MergeMems since the
1928 // optimizer doesn't like that.
1929 if (final_mem->is_MergeMem()) {
1930 Node_List wl;
1931 for (SimpleDUIterator i(final_mem); i.has_next(); i.next()) {
1932 Node* m = i.get();
1933 if (m->is_MergeMem() && !wl.contains(m)) {
1934 wl.push(m);
1935 }
1936 }
1937 while (wl.size() > 0) {
1938 _gvn.transform(wl.pop());
1939 }
1940 }
1941 }
1942
1943
1944 //------------------------------increment_counter------------------------------
1945 // for statistics: increment a VM counter by 1
1946
1947 void GraphKit::increment_counter(address counter_addr) {
1948 Node* adr1 = makecon(TypeRawPtr::make(counter_addr));
1949 increment_counter(adr1);
1950 }
1951
1952 void GraphKit::increment_counter(Node* counter_addr) {
1953 int adr_type = Compile::AliasIdxRaw;
1954 Node* ctrl = control();
1955 Node* cnt = make_load(ctrl, counter_addr, TypeInt::INT, T_INT, adr_type, MemNode::unordered);
1956 Node* incr = _gvn.transform(new (C) AddINode(cnt, _gvn.intcon(1)));
1957 store_to_memory(ctrl, counter_addr, incr, T_INT, adr_type, MemNode::unordered);
1958 }
1959
1960
1961 //------------------------------uncommon_trap----------------------------------
1962 // Bail out to the interpreter in mid-method. Implemented by calling the
1963 // uncommon_trap blob. This helper function inserts a runtime call with the
1964 // right debug info.
1965 void GraphKit::uncommon_trap(int trap_request,
1966 ciKlass* klass, const char* comment,
1967 bool must_throw,
1968 bool keep_exact_action) {
1969 if (failing()) stop();
1970 if (stopped()) return; // trap reachable?
1971
1972 // Note: If ProfileTraps is true, and if a deopt. actually
1973 // occurs here, the runtime will make sure an MDO exists. There is
1974 // no need to call method()->ensure_method_data() at this point.
1975
1976 // Set the stack pointer to the right value for reexecution:
1977 set_sp(reexecute_sp());
1978
1979 #ifdef ASSERT
1980 if (!must_throw) {
1981 // Make sure the stack has at least enough depth to execute
1982 // the current bytecode.
1983 int inputs, ignored_depth;
1984 if (compute_stack_effects(inputs, ignored_depth)) {
1985 assert(sp() >= inputs, err_msg_res("must have enough JVMS stack to execute %s: sp=%d, inputs=%d",
1986 Bytecodes::name(java_bc()), sp(), inputs));
1987 }
1988 }
1989 #endif
1990
1991 Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
1992 Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
1993
1994 switch (action) {
1995 case Deoptimization::Action_maybe_recompile:
1996 case Deoptimization::Action_reinterpret:
1997 // Temporary fix for 6529811 to allow virtual calls to be sure they
1998 // get the chance to go from mono->bi->mega
1999 if (!keep_exact_action &&
2000 Deoptimization::trap_request_index(trap_request) < 0 &&
2001 too_many_recompiles(reason)) {
2002 // This BCI is causing too many recompilations.
2003 action = Deoptimization::Action_none;
2004 trap_request = Deoptimization::make_trap_request(reason, action);
2005 } else {
2006 C->set_trap_can_recompile(true);
2007 }
2008 break;
2009 case Deoptimization::Action_make_not_entrant:
2010 C->set_trap_can_recompile(true);
2011 break;
2012 #ifdef ASSERT
2013 case Deoptimization::Action_none:
2014 case Deoptimization::Action_make_not_compilable:
2015 break;
2016 default:
2017 fatal(err_msg_res("unknown action %d: %s", action, Deoptimization::trap_action_name(action)));
2018 break;
2019 #endif
2020 }
2021
2022 if (TraceOptoParse) {
2023 char buf[100];
2024 tty->print_cr("Uncommon trap %s at bci:%d",
2025 Deoptimization::format_trap_request(buf, sizeof(buf),
2026 trap_request), bci());
2027 }
2028
2029 CompileLog* log = C->log();
2030 if (log != NULL) {
2031 int kid = (klass == NULL)? -1: log->identify(klass);
2032 log->begin_elem("uncommon_trap bci='%d'", bci());
2033 char buf[100];
2034 log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf),
2035 trap_request));
2036 if (kid >= 0) log->print(" klass='%d'", kid);
2037 if (comment != NULL) log->print(" comment='%s'", comment);
2038 log->end_elem();
2039 }
2040
2041 // Make sure any guarding test views this path as very unlikely
2042 Node *i0 = control()->in(0);
2043 if (i0 != NULL && i0->is_If()) { // Found a guarding if test?
2044 IfNode *iff = i0->as_If();
2045 float f = iff->_prob; // Get prob
2046 if (control()->Opcode() == Op_IfTrue) {
2047 if (f > PROB_UNLIKELY_MAG(4))
2048 iff->_prob = PROB_MIN;
2049 } else {
2050 if (f < PROB_LIKELY_MAG(4))
2051 iff->_prob = PROB_MAX;
2052 }
2053 }
2054
2055 // Clear out dead values from the debug info.
2056 kill_dead_locals();
2057
2058 // Now insert the uncommon trap subroutine call
2059 address call_addr = SharedRuntime::uncommon_trap_blob()->entry_point();
2060 const TypePtr* no_memory_effects = NULL;
2061 // Pass the index of the class to be loaded
2062 Node* call = make_runtime_call(RC_NO_LEAF | RC_UNCOMMON |
2063 (must_throw ? RC_MUST_THROW : 0),
2064 OptoRuntime::uncommon_trap_Type(),
2065 call_addr, "uncommon_trap", no_memory_effects,
2066 intcon(trap_request));
2067 assert(call->as_CallStaticJava()->uncommon_trap_request() == trap_request,
2068 "must extract request correctly from the graph");
2069 assert(trap_request != 0, "zero value reserved by uncommon_trap_request");
2070
2071 call->set_req(TypeFunc::ReturnAdr, returnadr());
2072 // The debug info is the only real input to this call.
2073
2074 // Halt-and-catch fire here. The above call should never return!
2075 HaltNode* halt = new(C) HaltNode(control(), frameptr());
2076 _gvn.set_type_bottom(halt);
2077 root()->add_req(halt);
2078
2079 stop_and_kill_map();
2080 }
2081
2082
2083 //--------------------------just_allocated_object------------------------------
2084 // Report the object that was just allocated.
2085 // It must be the case that there are no intervening safepoints.
2086 // We use this to determine if an object is so "fresh" that
2087 // it does not require card marks.
2088 Node* GraphKit::just_allocated_object(Node* current_control) {
2089 if (C->recent_alloc_ctl() == current_control)
2090 return C->recent_alloc_obj();
2091 return NULL;
2092 }
2093
2094
2095 void GraphKit::round_double_arguments(ciMethod* dest_method) {
2096 // (Note: TypeFunc::make has a cache that makes this fast.)
2097 const TypeFunc* tf = TypeFunc::make(dest_method);
2098 int nargs = tf->_domain->_cnt - TypeFunc::Parms;
2099 for (int j = 0; j < nargs; j++) {
2100 const Type *targ = tf->_domain->field_at(j + TypeFunc::Parms);
2101 if( targ->basic_type() == T_DOUBLE ) {
2102 // If any parameters are doubles, they must be rounded before
2103 // the call, dstore_rounding does gvn.transform
2104 Node *arg = argument(j);
2105 arg = dstore_rounding(arg);
2106 set_argument(j, arg);
2107 }
2108 }
2109 }
2110
2111 /**
2112 * Record profiling data exact_kls for Node n with the type system so
2113 * that it can propagate it (speculation)
2114 *
2115 * @param n node that the type applies to
2116 * @param exact_kls type from profiling
2117 *
2118 * @return node with improved type
2119 */
2120 Node* GraphKit::record_profile_for_speculation(Node* n, ciKlass* exact_kls) {
2121 const Type* current_type = _gvn.type(n);
2122 assert(UseTypeSpeculation, "type speculation must be on");
2123
2124 const TypeOopPtr* speculative = current_type->speculative();
2125
2126 if (current_type->would_improve_type(exact_kls, jvms()->depth())) {
2127 const TypeKlassPtr* tklass = TypeKlassPtr::make(exact_kls);
2128 const TypeOopPtr* xtype = tklass->as_instance_type();
2129 assert(xtype->klass_is_exact(), "Should be exact");
2130 // record the new speculative type's depth
2131 speculative = xtype->with_inline_depth(jvms()->depth());
2132 }
2133
2134 if (speculative != current_type->speculative()) {
2135 // Build a type with a speculative type (what we think we know
2136 // about the type but will need a guard when we use it)
2137 const TypeOopPtr* spec_type = TypeOopPtr::make(TypePtr::BotPTR, Type::OffsetBot, TypeOopPtr::InstanceBot, speculative);
2138 // We're changing the type, we need a new CheckCast node to carry
2139 // the new type. The new type depends on the control: what
2140 // profiling tells us is only valid from here as far as we can
2141 // tell.
2142 Node* cast = new(C) CheckCastPPNode(control(), n, current_type->remove_speculative()->join_speculative(spec_type));
2143 cast = _gvn.transform(cast);
2144 replace_in_map(n, cast);
2145 n = cast;
2146 }
2147
2148 return n;
2149 }
2150
2151 /**
2152 * Record profiling data from receiver profiling at an invoke with the
2153 * type system so that it can propagate it (speculation)
2154 *
2155 * @param n receiver node
2156 *
2157 * @return node with improved type
2158 */
2159 Node* GraphKit::record_profiled_receiver_for_speculation(Node* n) {
2160 if (!UseTypeSpeculation) {
2161 return n;
2162 }
2163 ciKlass* exact_kls = profile_has_unique_klass();
2164 return record_profile_for_speculation(n, exact_kls);
2165 }
2166
2167 /**
2168 * Record profiling data from argument profiling at an invoke with the
2169 * type system so that it can propagate it (speculation)
2170 *
2171 * @param dest_method target method for the call
2172 * @param bc what invoke bytecode is this?
2173 */
2174 void GraphKit::record_profiled_arguments_for_speculation(ciMethod* dest_method, Bytecodes::Code bc) {
2175 if (!UseTypeSpeculation) {
2176 return;
2177 }
2178 const TypeFunc* tf = TypeFunc::make(dest_method);
2179 int nargs = tf->_domain->_cnt - TypeFunc::Parms;
2180 int skip = Bytecodes::has_receiver(bc) ? 1 : 0;
2181 for (int j = skip, i = 0; j < nargs && i < TypeProfileArgsLimit; j++) {
2182 const Type *targ = tf->_domain->field_at(j + TypeFunc::Parms);
2183 if (targ->basic_type() == T_OBJECT || targ->basic_type() == T_ARRAY) {
2184 ciKlass* better_type = method()->argument_profiled_type(bci(), i);
2185 if (better_type != NULL) {
2186 record_profile_for_speculation(argument(j), better_type);
2187 }
2188 i++;
2189 }
2190 }
2191 }
2192
2193 /**
2194 * Record profiling data from parameter profiling at an invoke with
2195 * the type system so that it can propagate it (speculation)
2196 */
2197 void GraphKit::record_profiled_parameters_for_speculation() {
2198 if (!UseTypeSpeculation) {
2199 return;
2200 }
2201 for (int i = 0, j = 0; i < method()->arg_size() ; i++) {
2202 if (_gvn.type(local(i))->isa_oopptr()) {
2203 ciKlass* better_type = method()->parameter_profiled_type(j);
2204 if (better_type != NULL) {
2205 record_profile_for_speculation(local(i), better_type);
2206 }
2207 j++;
2208 }
2209 }
2210 }
2211
2212 void GraphKit::round_double_result(ciMethod* dest_method) {
2213 // A non-strict method may return a double value which has an extended
2214 // exponent, but this must not be visible in a caller which is 'strict'
2215 // If a strict caller invokes a non-strict callee, round a double result
2216
2217 BasicType result_type = dest_method->return_type()->basic_type();
2218 assert( method() != NULL, "must have caller context");
2219 if( result_type == T_DOUBLE && method()->is_strict() && !dest_method->is_strict() ) {
2220 // Destination method's return value is on top of stack
2221 // dstore_rounding() does gvn.transform
2222 Node *result = pop_pair();
2223 result = dstore_rounding(result);
2224 push_pair(result);
2225 }
2226 }
2227
2228 // rounding for strict float precision conformance
2229 Node* GraphKit::precision_rounding(Node* n) {
2230 return UseStrictFP && _method->flags().is_strict()
2231 && UseSSE == 0 && Matcher::strict_fp_requires_explicit_rounding
2232 ? _gvn.transform( new (C) RoundFloatNode(0, n) )
2233 : n;
2234 }
2235
2236 // rounding for strict double precision conformance
2237 Node* GraphKit::dprecision_rounding(Node *n) {
2238 return UseStrictFP && _method->flags().is_strict()
2239 && UseSSE <= 1 && Matcher::strict_fp_requires_explicit_rounding
2240 ? _gvn.transform( new (C) RoundDoubleNode(0, n) )
2241 : n;
2242 }
2243
2244 // rounding for non-strict double stores
2245 Node* GraphKit::dstore_rounding(Node* n) {
2246 return Matcher::strict_fp_requires_explicit_rounding
2247 && UseSSE <= 1
2248 ? _gvn.transform( new (C) RoundDoubleNode(0, n) )
2249 : n;
2250 }
2251
2252 //=============================================================================
2253 // Generate a fast path/slow path idiom. Graph looks like:
2254 // [foo] indicates that 'foo' is a parameter
2255 //
2256 // [in] NULL
2257 // \ /
2258 // CmpP
2259 // Bool ne
2260 // If
2261 // / \
2262 // True False-<2>
2263 // / |
2264 // / cast_not_null
2265 // Load | | ^
2266 // [fast_test] | |
2267 // gvn to opt_test | |
2268 // / \ | <1>
2269 // True False |
2270 // | \\ |
2271 // [slow_call] \[fast_result]
2272 // Ctl Val \ \
2273 // | \ \
2274 // Catch <1> \ \
2275 // / \ ^ \ \
2276 // Ex No_Ex | \ \
2277 // | \ \ | \ <2> \
2278 // ... \ [slow_res] | | \ [null_result]
2279 // \ \--+--+--- | |
2280 // \ | / \ | /
2281 // --------Region Phi
2282 //
2283 //=============================================================================
2284 // Code is structured as a series of driver functions all called 'do_XXX' that
2285 // call a set of helper functions. Helper functions first, then drivers.
2286
2287 //------------------------------null_check_oop---------------------------------
2288 // Null check oop. Set null-path control into Region in slot 3.
2289 // Make a cast-not-nullness use the other not-null control. Return cast.
2290 Node* GraphKit::null_check_oop(Node* value, Node* *null_control,
2291 bool never_see_null, bool safe_for_replace) {
2292 // Initial NULL check taken path
2293 (*null_control) = top();
2294 Node* cast = null_check_common(value, T_OBJECT, false, null_control);
2295
2296 // Generate uncommon_trap:
2297 if (never_see_null && (*null_control) != top()) {
2298 // If we see an unexpected null at a check-cast we record it and force a
2299 // recompile; the offending check-cast will be compiled to handle NULLs.
2300 // If we see more than one offending BCI, then all checkcasts in the
2301 // method will be compiled to handle NULLs.
2302 PreserveJVMState pjvms(this);
2303 set_control(*null_control);
2304 replace_in_map(value, null());
2305 uncommon_trap(Deoptimization::Reason_null_check,
2306 Deoptimization::Action_make_not_entrant);
2307 (*null_control) = top(); // NULL path is dead
2308 }
2309 if ((*null_control) == top() && safe_for_replace) {
2310 replace_in_map(value, cast);
2311 }
2312
2313 // Cast away null-ness on the result
2314 return cast;
2315 }
2316
2317 //------------------------------opt_iff----------------------------------------
2318 // Optimize the fast-check IfNode. Set the fast-path region slot 2.
2319 // Return slow-path control.
2320 Node* GraphKit::opt_iff(Node* region, Node* iff) {
2321 IfNode *opt_iff = _gvn.transform(iff)->as_If();
2322
2323 // Fast path taken; set region slot 2
2324 Node *fast_taken = _gvn.transform( new (C) IfFalseNode(opt_iff) );
2325 region->init_req(2,fast_taken); // Capture fast-control
2326
2327 // Fast path not-taken, i.e. slow path
2328 Node *slow_taken = _gvn.transform( new (C) IfTrueNode(opt_iff) );
2329 return slow_taken;
2330 }
2331
2332 //-----------------------------make_runtime_call-------------------------------
2333 Node* GraphKit::make_runtime_call(int flags,
2334 const TypeFunc* call_type, address call_addr,
2335 const char* call_name,
2336 const TypePtr* adr_type,
2337 // The following parms are all optional.
2338 // The first NULL ends the list.
2339 Node* parm0, Node* parm1,
2340 Node* parm2, Node* parm3,
2341 Node* parm4, Node* parm5,
2342 Node* parm6, Node* parm7) {
2343 // Slow-path call
2344 bool is_leaf = !(flags & RC_NO_LEAF);
2345 bool has_io = (!is_leaf && !(flags & RC_NO_IO));
2346 if (call_name == NULL) {
2347 assert(!is_leaf, "must supply name for leaf");
2348 call_name = OptoRuntime::stub_name(call_addr);
2349 }
2350 CallNode* call;
2351 if (!is_leaf) {
2352 call = new(C) CallStaticJavaNode(call_type, call_addr, call_name,
2353 bci(), adr_type);
2354 } else if (flags & RC_NO_FP) {
2355 call = new(C) CallLeafNoFPNode(call_type, call_addr, call_name, adr_type);
2356 } else {
2357 call = new(C) CallLeafNode(call_type, call_addr, call_name, adr_type);
2358 }
2359
2360 // The following is similar to set_edges_for_java_call,
2361 // except that the memory effects of the call are restricted to AliasIdxRaw.
2362
2363 // Slow path call has no side-effects, uses few values
2364 bool wide_in = !(flags & RC_NARROW_MEM);
2365 bool wide_out = (C->get_alias_index(adr_type) == Compile::AliasIdxBot);
2366
2367 Node* prev_mem = NULL;
2368 if (wide_in) {
2369 prev_mem = set_predefined_input_for_runtime_call(call);
2370 } else {
2371 assert(!wide_out, "narrow in => narrow out");
2372 Node* narrow_mem = memory(adr_type);
2373 prev_mem = reset_memory();
2374 map()->set_memory(narrow_mem);
2375 set_predefined_input_for_runtime_call(call);
2376 }
2377
2378 // Hook each parm in order. Stop looking at the first NULL.
2379 if (parm0 != NULL) { call->init_req(TypeFunc::Parms+0, parm0);
2380 if (parm1 != NULL) { call->init_req(TypeFunc::Parms+1, parm1);
2381 if (parm2 != NULL) { call->init_req(TypeFunc::Parms+2, parm2);
2382 if (parm3 != NULL) { call->init_req(TypeFunc::Parms+3, parm3);
2383 if (parm4 != NULL) { call->init_req(TypeFunc::Parms+4, parm4);
2384 if (parm5 != NULL) { call->init_req(TypeFunc::Parms+5, parm5);
2385 if (parm6 != NULL) { call->init_req(TypeFunc::Parms+6, parm6);
2386 if (parm7 != NULL) { call->init_req(TypeFunc::Parms+7, parm7);
2387 /* close each nested if ===> */ } } } } } } } }
2388 assert(call->in(call->req()-1) != NULL, "must initialize all parms");
2389
2390 if (!is_leaf) {
2391 // Non-leaves can block and take safepoints:
2392 add_safepoint_edges(call, ((flags & RC_MUST_THROW) != 0));
2393 }
2394 // Non-leaves can throw exceptions:
2395 if (has_io) {
2396 call->set_req(TypeFunc::I_O, i_o());
2397 }
2398
2399 if (flags & RC_UNCOMMON) {
2400 // Set the count to a tiny probability. Cf. Estimate_Block_Frequency.
2401 // (An "if" probability corresponds roughly to an unconditional count.
2402 // Sort of.)
2403 call->set_cnt(PROB_UNLIKELY_MAG(4));
2404 }
2405
2406 Node* c = _gvn.transform(call);
2407 assert(c == call, "cannot disappear");
2408
2409 if (wide_out) {
2410 // Slow path call has full side-effects.
2411 set_predefined_output_for_runtime_call(call);
2412 } else {
2413 // Slow path call has few side-effects, and/or sets few values.
2414 set_predefined_output_for_runtime_call(call, prev_mem, adr_type);
2415 }
2416
2417 if (has_io) {
2418 set_i_o(_gvn.transform(new (C) ProjNode(call, TypeFunc::I_O)));
2419 }
2420 return call;
2421
2422 }
2423
2424 //------------------------------merge_memory-----------------------------------
2425 // Merge memory from one path into the current memory state.
2426 void GraphKit::merge_memory(Node* new_mem, Node* region, int new_path) {
2427 for (MergeMemStream mms(merged_memory(), new_mem->as_MergeMem()); mms.next_non_empty2(); ) {
2428 Node* old_slice = mms.force_memory();
2429 Node* new_slice = mms.memory2();
2430 if (old_slice != new_slice) {
2431 PhiNode* phi;
2432 if (new_slice->is_Phi() && new_slice->as_Phi()->region() == region) {
2433 phi = new_slice->as_Phi();
2434 #ifdef ASSERT
2435 if (old_slice->is_Phi() && old_slice->as_Phi()->region() == region)
2436 old_slice = old_slice->in(new_path);
2437 // Caller is responsible for ensuring that any pre-existing
2438 // phis are already aware of old memory.
2439 int old_path = (new_path > 1) ? 1 : 2; // choose old_path != new_path
2440 assert(phi->in(old_path) == old_slice, "pre-existing phis OK");
2441 #endif
2442 mms.set_memory(phi);
2443 } else {
2444 phi = PhiNode::make(region, old_slice, Type::MEMORY, mms.adr_type(C));
2445 _gvn.set_type(phi, Type::MEMORY);
2446 phi->set_req(new_path, new_slice);
2447 mms.set_memory(_gvn.transform(phi)); // assume it is complete
2448 }
2449 }
2450 }
2451 }
2452
2453 //------------------------------make_slow_call_ex------------------------------
2454 // Make the exception handler hookups for the slow call
2455 void GraphKit::make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj) {
2456 if (stopped()) return;
2457
2458 // Make a catch node with just two handlers: fall-through and catch-all
2459 Node* i_o = _gvn.transform( new (C) ProjNode(call, TypeFunc::I_O, separate_io_proj) );
2460 Node* catc = _gvn.transform( new (C) CatchNode(control(), i_o, 2) );
2461 Node* norm = _gvn.transform( new (C) CatchProjNode(catc, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci) );
2462 Node* excp = _gvn.transform( new (C) CatchProjNode(catc, CatchProjNode::catch_all_index, CatchProjNode::no_handler_bci) );
2463
2464 { PreserveJVMState pjvms(this);
2465 set_control(excp);
2466 set_i_o(i_o);
2467
2468 if (excp != top()) {
2469 // Create an exception state also.
2470 // Use an exact type if the caller has specified a specific exception.
2471 const Type* ex_type = TypeOopPtr::make_from_klass_unique(ex_klass)->cast_to_ptr_type(TypePtr::NotNull);
2472 Node* ex_oop = new (C) CreateExNode(ex_type, control(), i_o);
2473 add_exception_state(make_exception_state(_gvn.transform(ex_oop)));
2474 }
2475 }
2476
2477 // Get the no-exception control from the CatchNode.
2478 set_control(norm);
2479 }
2480
2481
2482 //-------------------------------gen_subtype_check-----------------------------
2483 // Generate a subtyping check. Takes as input the subtype and supertype.
2484 // Returns 2 values: sets the default control() to the true path and returns
2485 // the false path. Only reads invariant memory; sets no (visible) memory.
2486 // The PartialSubtypeCheckNode sets the hidden 1-word cache in the encoding
2487 // but that's not exposed to the optimizer. This call also doesn't take in an
2488 // Object; if you wish to check an Object you need to load the Object's class
2489 // prior to coming here.
2490 Node* GraphKit::gen_subtype_check(Node* subklass, Node* superklass) {
2491 // Fast check for identical types, perhaps identical constants.
2492 // The types can even be identical non-constants, in cases
2493 // involving Array.newInstance, Object.clone, etc.
2494 if (subklass == superklass)
2495 return top(); // false path is dead; no test needed.
2496
2497 if (_gvn.type(superklass)->singleton()) {
2498 ciKlass* superk = _gvn.type(superklass)->is_klassptr()->klass();
2499 ciKlass* subk = _gvn.type(subklass)->is_klassptr()->klass();
2500
2501 // In the common case of an exact superklass, try to fold up the
2502 // test before generating code. You may ask, why not just generate
2503 // the code and then let it fold up? The answer is that the generated
2504 // code will necessarily include null checks, which do not always
2505 // completely fold away. If they are also needless, then they turn
2506 // into a performance loss. Example:
2507 // Foo[] fa = blah(); Foo x = fa[0]; fa[1] = x;
2508 // Here, the type of 'fa' is often exact, so the store check
2509 // of fa[1]=x will fold up, without testing the nullness of x.
2510 switch (static_subtype_check(superk, subk)) {
2511 case SSC_always_false:
2512 {
2513 Node* always_fail = control();
2514 set_control(top());
2515 return always_fail;
2516 }
2517 case SSC_always_true:
2518 return top();
2519 case SSC_easy_test:
2520 {
2521 // Just do a direct pointer compare and be done.
2522 Node* cmp = _gvn.transform( new(C) CmpPNode(subklass, superklass) );
2523 Node* bol = _gvn.transform( new(C) BoolNode(cmp, BoolTest::eq) );
2524 IfNode* iff = create_and_xform_if(control(), bol, PROB_STATIC_FREQUENT, COUNT_UNKNOWN);
2525 set_control( _gvn.transform( new(C) IfTrueNode (iff) ) );
2526 return _gvn.transform( new(C) IfFalseNode(iff) );
2527 }
2528 case SSC_full_test:
2529 break;
2530 default:
2531 ShouldNotReachHere();
2532 }
2533 }
2534
2535 // %%% Possible further optimization: Even if the superklass is not exact,
2536 // if the subklass is the unique subtype of the superklass, the check
2537 // will always succeed. We could leave a dependency behind to ensure this.
2538
2539 // First load the super-klass's check-offset
2540 Node *p1 = basic_plus_adr( superklass, superklass, in_bytes(Klass::super_check_offset_offset()) );
2541 Node *chk_off = _gvn.transform(new (C) LoadINode(NULL, memory(p1), p1, _gvn.type(p1)->is_ptr(),
2542 TypeInt::INT, MemNode::unordered));
2543 int cacheoff_con = in_bytes(Klass::secondary_super_cache_offset());
2544 bool might_be_cache = (find_int_con(chk_off, cacheoff_con) == cacheoff_con);
2545
2546 // Load from the sub-klass's super-class display list, or a 1-word cache of
2547 // the secondary superclass list, or a failing value with a sentinel offset
2548 // if the super-klass is an interface or exceptionally deep in the Java
2549 // hierarchy and we have to scan the secondary superclass list the hard way.
2550 // Worst-case type is a little odd: NULL is allowed as a result (usually
2551 // klass loads can never produce a NULL).
2552 Node *chk_off_X = ConvI2X(chk_off);
2553 Node *p2 = _gvn.transform( new (C) AddPNode(subklass,subklass,chk_off_X) );
2554 // For some types like interfaces the following loadKlass is from a 1-word
2555 // cache which is mutable so can't use immutable memory. Other
2556 // types load from the super-class display table which is immutable.
2557 Node *kmem = might_be_cache ? memory(p2) : immutable_memory();
2558 Node *nkls = _gvn.transform( LoadKlassNode::make( _gvn, kmem, p2, _gvn.type(p2)->is_ptr(), TypeKlassPtr::OBJECT_OR_NULL ) );
2559
2560 // Compile speed common case: ARE a subtype and we canNOT fail
2561 if( superklass == nkls )
2562 return top(); // false path is dead; no test needed.
2563
2564 // See if we get an immediate positive hit. Happens roughly 83% of the
2565 // time. Test to see if the value loaded just previously from the subklass
2566 // is exactly the superklass.
2567 Node *cmp1 = _gvn.transform( new (C) CmpPNode( superklass, nkls ) );
2568 Node *bol1 = _gvn.transform( new (C) BoolNode( cmp1, BoolTest::eq ) );
2569 IfNode *iff1 = create_and_xform_if( control(), bol1, PROB_LIKELY(0.83f), COUNT_UNKNOWN );
2570 Node *iftrue1 = _gvn.transform( new (C) IfTrueNode ( iff1 ) );
2571 set_control( _gvn.transform( new (C) IfFalseNode( iff1 ) ) );
2572
2573 // Compile speed common case: Check for being deterministic right now. If
2574 // chk_off is a constant and not equal to cacheoff then we are NOT a
2575 // subklass. In this case we need exactly the 1 test above and we can
2576 // return those results immediately.
2577 if (!might_be_cache) {
2578 Node* not_subtype_ctrl = control();
2579 set_control(iftrue1); // We need exactly the 1 test above
2580 return not_subtype_ctrl;
2581 }
2582
2583 // Gather the various success & failures here
2584 RegionNode *r_ok_subtype = new (C) RegionNode(4);
2585 record_for_igvn(r_ok_subtype);
2586 RegionNode *r_not_subtype = new (C) RegionNode(3);
2587 record_for_igvn(r_not_subtype);
2588
2589 r_ok_subtype->init_req(1, iftrue1);
2590
2591 // Check for immediate negative hit. Happens roughly 11% of the time (which
2592 // is roughly 63% of the remaining cases). Test to see if the loaded
2593 // check-offset points into the subklass display list or the 1-element
2594 // cache. If it points to the display (and NOT the cache) and the display
2595 // missed then it's not a subtype.
2596 Node *cacheoff = _gvn.intcon(cacheoff_con);
2597 Node *cmp2 = _gvn.transform( new (C) CmpINode( chk_off, cacheoff ) );
2598 Node *bol2 = _gvn.transform( new (C) BoolNode( cmp2, BoolTest::ne ) );
2599 IfNode *iff2 = create_and_xform_if( control(), bol2, PROB_LIKELY(0.63f), COUNT_UNKNOWN );
2600 r_not_subtype->init_req(1, _gvn.transform( new (C) IfTrueNode (iff2) ) );
2601 set_control( _gvn.transform( new (C) IfFalseNode(iff2) ) );
2602
2603 // Check for self. Very rare to get here, but it is taken 1/3 the time.
2604 // No performance impact (too rare) but allows sharing of secondary arrays
2605 // which has some footprint reduction.
2606 Node *cmp3 = _gvn.transform( new (C) CmpPNode( subklass, superklass ) );
2607 Node *bol3 = _gvn.transform( new (C) BoolNode( cmp3, BoolTest::eq ) );
2608 IfNode *iff3 = create_and_xform_if( control(), bol3, PROB_LIKELY(0.36f), COUNT_UNKNOWN );
2609 r_ok_subtype->init_req(2, _gvn.transform( new (C) IfTrueNode ( iff3 ) ) );
2610 set_control( _gvn.transform( new (C) IfFalseNode( iff3 ) ) );
2611
2612 // -- Roads not taken here: --
2613 // We could also have chosen to perform the self-check at the beginning
2614 // of this code sequence, as the assembler does. This would not pay off
2615 // the same way, since the optimizer, unlike the assembler, can perform
2616 // static type analysis to fold away many successful self-checks.
2617 // Non-foldable self checks work better here in second position, because
2618 // the initial primary superclass check subsumes a self-check for most
2619 // types. An exception would be a secondary type like array-of-interface,
2620 // which does not appear in its own primary supertype display.
2621 // Finally, we could have chosen to move the self-check into the
2622 // PartialSubtypeCheckNode, and from there out-of-line in a platform
2623 // dependent manner. But it is worthwhile to have the check here,
2624 // where it can be perhaps be optimized. The cost in code space is
2625 // small (register compare, branch).
2626
2627 // Now do a linear scan of the secondary super-klass array. Again, no real
2628 // performance impact (too rare) but it's gotta be done.
2629 // Since the code is rarely used, there is no penalty for moving it
2630 // out of line, and it can only improve I-cache density.
2631 // The decision to inline or out-of-line this final check is platform
2632 // dependent, and is found in the AD file definition of PartialSubtypeCheck.
2633 Node* psc = _gvn.transform(
2634 new (C) PartialSubtypeCheckNode(control(), subklass, superklass) );
2635
2636 Node *cmp4 = _gvn.transform( new (C) CmpPNode( psc, null() ) );
2637 Node *bol4 = _gvn.transform( new (C) BoolNode( cmp4, BoolTest::ne ) );
2638 IfNode *iff4 = create_and_xform_if( control(), bol4, PROB_FAIR, COUNT_UNKNOWN );
2639 r_not_subtype->init_req(2, _gvn.transform( new (C) IfTrueNode (iff4) ) );
2640 r_ok_subtype ->init_req(3, _gvn.transform( new (C) IfFalseNode(iff4) ) );
2641
2642 // Return false path; set default control to true path.
2643 set_control( _gvn.transform(r_ok_subtype) );
2644 return _gvn.transform(r_not_subtype);
2645 }
2646
2647 //----------------------------static_subtype_check-----------------------------
2648 // Shortcut important common cases when superklass is exact:
2649 // (0) superklass is java.lang.Object (can occur in reflective code)
2650 // (1) subklass is already limited to a subtype of superklass => always ok
2651 // (2) subklass does not overlap with superklass => always fail
2652 // (3) superklass has NO subtypes and we can check with a simple compare.
2653 int GraphKit::static_subtype_check(ciKlass* superk, ciKlass* subk) {
2654 if (StressReflectiveCode) {
2655 return SSC_full_test; // Let caller generate the general case.
2656 }
2657
2658 if (superk == env()->Object_klass()) {
2659 return SSC_always_true; // (0) this test cannot fail
2660 }
2661
2662 ciType* superelem = superk;
2663 if (superelem->is_array_klass())
2664 superelem = superelem->as_array_klass()->base_element_type();
2665
2666 if (!subk->is_interface()) { // cannot trust static interface types yet
2667 if (subk->is_subtype_of(superk)) {
2668 return SSC_always_true; // (1) false path dead; no dynamic test needed
2669 }
2670 if (!(superelem->is_klass() && superelem->as_klass()->is_interface()) &&
2671 !superk->is_subtype_of(subk)) {
2672 return SSC_always_false;
2673 }
2674 }
2675
2676 // If casting to an instance klass, it must have no subtypes
2677 if (superk->is_interface()) {
2678 // Cannot trust interfaces yet.
2679 // %%% S.B. superk->nof_implementors() == 1
2680 } else if (superelem->is_instance_klass()) {
2681 ciInstanceKlass* ik = superelem->as_instance_klass();
2682 if (!ik->has_subklass() && !ik->is_interface()) {
2683 if (!ik->is_final()) {
2684 // Add a dependency if there is a chance of a later subclass.
2685 C->dependencies()->assert_leaf_type(ik);
2686 }
2687 return SSC_easy_test; // (3) caller can do a simple ptr comparison
2688 }
2689 } else {
2690 // A primitive array type has no subtypes.
2691 return SSC_easy_test; // (3) caller can do a simple ptr comparison
2692 }
2693
2694 return SSC_full_test;
2695 }
2696
2697 // Profile-driven exact type check:
2698 Node* GraphKit::type_check_receiver(Node* receiver, ciKlass* klass,
2699 float prob,
2700 Node* *casted_receiver) {
2701 const TypeKlassPtr* tklass = TypeKlassPtr::make(klass);
2702 Node* recv_klass = load_object_klass(receiver);
2703 Node* want_klass = makecon(tklass);
2704 Node* cmp = _gvn.transform( new(C) CmpPNode(recv_klass, want_klass) );
2705 Node* bol = _gvn.transform( new(C) BoolNode(cmp, BoolTest::eq) );
2706 IfNode* iff = create_and_xform_if(control(), bol, prob, COUNT_UNKNOWN);
2707 set_control( _gvn.transform( new(C) IfTrueNode (iff) ));
2708 Node* fail = _gvn.transform( new(C) IfFalseNode(iff) );
2709
2710 const TypeOopPtr* recv_xtype = tklass->as_instance_type();
2711 assert(recv_xtype->klass_is_exact(), "");
2712
2713 // Subsume downstream occurrences of receiver with a cast to
2714 // recv_xtype, since now we know what the type will be.
2715 Node* cast = new(C) CheckCastPPNode(control(), receiver, recv_xtype);
2716 (*casted_receiver) = _gvn.transform(cast);
2717 // (User must make the replace_in_map call.)
2718
2719 return fail;
2720 }
2721
2722
2723 //------------------------------seems_never_null-------------------------------
2724 // Use null_seen information if it is available from the profile.
2725 // If we see an unexpected null at a type check we record it and force a
2726 // recompile; the offending check will be recompiled to handle NULLs.
2727 // If we see several offending BCIs, then all checks in the
2728 // method will be recompiled.
2729 bool GraphKit::seems_never_null(Node* obj, ciProfileData* data) {
2730 if (UncommonNullCast // Cutout for this technique
2731 && obj != null() // And not the -Xcomp stupid case?
2732 && !too_many_traps(Deoptimization::Reason_null_check)
2733 ) {
2734 if (data == NULL)
2735 // Edge case: no mature data. Be optimistic here.
2736 return true;
2737 // If the profile has not seen a null, assume it won't happen.
2738 assert(java_bc() == Bytecodes::_checkcast ||
2739 java_bc() == Bytecodes::_instanceof ||
2740 java_bc() == Bytecodes::_aastore, "MDO must collect null_seen bit here");
2741 return !data->as_BitData()->null_seen();
2742 }
2743 return false;
2744 }
2745
2746 //------------------------maybe_cast_profiled_receiver-------------------------
2747 // If the profile has seen exactly one type, narrow to exactly that type.
2748 // Subsequent type checks will always fold up.
2749 Node* GraphKit::maybe_cast_profiled_receiver(Node* not_null_obj,
2750 ciKlass* require_klass,
2751 ciKlass* spec_klass,
2752 bool safe_for_replace) {
2753 if (!UseTypeProfile || !TypeProfileCasts) return NULL;
2754
2755 Deoptimization::DeoptReason reason = spec_klass == NULL ? Deoptimization::Reason_class_check : Deoptimization::Reason_speculate_class_check;
2756
2757 // Make sure we haven't already deoptimized from this tactic.
2758 if (too_many_traps(reason))
2759 return NULL;
2760
2761 // (No, this isn't a call, but it's enough like a virtual call
2762 // to use the same ciMethod accessor to get the profile info...)
2763 // If we have a speculative type use it instead of profiling (which
2764 // may not help us)
2765 ciKlass* exact_kls = spec_klass == NULL ? profile_has_unique_klass() : spec_klass;
2766 if (exact_kls != NULL) {// no cast failures here
2767 if (require_klass == NULL ||
2768 static_subtype_check(require_klass, exact_kls) == SSC_always_true) {
2769 // If we narrow the type to match what the type profile sees or
2770 // the speculative type, we can then remove the rest of the
2771 // cast.
2772 // This is a win, even if the exact_kls is very specific,
2773 // because downstream operations, such as method calls,
2774 // will often benefit from the sharper type.
2775 Node* exact_obj = not_null_obj; // will get updated in place...
2776 Node* slow_ctl = type_check_receiver(exact_obj, exact_kls, 1.0,
2777 &exact_obj);
2778 { PreserveJVMState pjvms(this);
2779 set_control(slow_ctl);
2780 uncommon_trap(reason,
2781 Deoptimization::Action_maybe_recompile);
2782 }
2783 if (safe_for_replace) {
2784 replace_in_map(not_null_obj, exact_obj);
2785 }
2786 return exact_obj;
2787 }
2788 // assert(ssc == SSC_always_true)... except maybe the profile lied to us.
2789 }
2790
2791 return NULL;
2792 }
2793
2794 /**
2795 * Cast obj to type and emit guard unless we had too many traps here
2796 * already
2797 *
2798 * @param obj node being casted
2799 * @param type type to cast the node to
2800 * @param not_null true if we know node cannot be null
2801 */
2802 Node* GraphKit::maybe_cast_profiled_obj(Node* obj,
2803 ciKlass* type,
2804 bool not_null) {
2805 // type == NULL if profiling tells us this object is always null
2806 if (type != NULL) {
2807 Deoptimization::DeoptReason class_reason = Deoptimization::Reason_speculate_class_check;
2808 Deoptimization::DeoptReason null_reason = Deoptimization::Reason_null_check;
2809 if (!too_many_traps(null_reason) &&
2810 !too_many_traps(class_reason)) {
2811 Node* not_null_obj = NULL;
2812 // not_null is true if we know the object is not null and
2813 // there's no need for a null check
2814 if (!not_null) {
2815 Node* null_ctl = top();
2816 not_null_obj = null_check_oop(obj, &null_ctl, true, true);
2817 assert(null_ctl->is_top(), "no null control here");
2818 } else {
2819 not_null_obj = obj;
2820 }
2821
2822 Node* exact_obj = not_null_obj;
2823 ciKlass* exact_kls = type;
2824 Node* slow_ctl = type_check_receiver(exact_obj, exact_kls, 1.0,
2825 &exact_obj);
2826 {
2827 PreserveJVMState pjvms(this);
2828 set_control(slow_ctl);
2829 uncommon_trap(class_reason,
2830 Deoptimization::Action_maybe_recompile);
2831 }
2832 replace_in_map(not_null_obj, exact_obj);
2833 obj = exact_obj;
2834 }
2835 } else {
2836 if (!too_many_traps(Deoptimization::Reason_null_assert)) {
2837 Node* exact_obj = null_assert(obj);
2838 replace_in_map(obj, exact_obj);
2839 obj = exact_obj;
2840 }
2841 }
2842 return obj;
2843 }
2844
2845 //-------------------------------gen_instanceof--------------------------------
2846 // Generate an instance-of idiom. Used by both the instance-of bytecode
2847 // and the reflective instance-of call.
2848 Node* GraphKit::gen_instanceof(Node* obj, Node* superklass, bool safe_for_replace) {
2849 kill_dead_locals(); // Benefit all the uncommon traps
2850 assert( !stopped(), "dead parse path should be checked in callers" );
2851 assert(!TypePtr::NULL_PTR->higher_equal(_gvn.type(superklass)->is_klassptr()),
2852 "must check for not-null not-dead klass in callers");
2853
2854 // Make the merge point
2855 enum { _obj_path = 1, _fail_path, _null_path, PATH_LIMIT };
2856 RegionNode* region = new(C) RegionNode(PATH_LIMIT);
2857 Node* phi = new(C) PhiNode(region, TypeInt::BOOL);
2858 C->set_has_split_ifs(true); // Has chance for split-if optimization
2859
2860 ciProfileData* data = NULL;
2861 if (java_bc() == Bytecodes::_instanceof) { // Only for the bytecode
2862 data = method()->method_data()->bci_to_data(bci());
2863 }
2864 bool never_see_null = (ProfileDynamicTypes // aggressive use of profile
2865 && seems_never_null(obj, data));
2866
2867 // Null check; get casted pointer; set region slot 3
2868 Node* null_ctl = top();
2869 Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace);
2870
2871 // If not_null_obj is dead, only null-path is taken
2872 if (stopped()) { // Doing instance-of on a NULL?
2873 set_control(null_ctl);
2874 return intcon(0);
2875 }
2876 region->init_req(_null_path, null_ctl);
2877 phi ->init_req(_null_path, intcon(0)); // Set null path value
2878 if (null_ctl == top()) {
2879 // Do this eagerly, so that pattern matches like is_diamond_phi
2880 // will work even during parsing.
2881 assert(_null_path == PATH_LIMIT-1, "delete last");
2882 region->del_req(_null_path);
2883 phi ->del_req(_null_path);
2884 }
2885
2886 // Do we know the type check always succeed?
2887 bool known_statically = false;
2888 if (_gvn.type(superklass)->singleton()) {
2889 ciKlass* superk = _gvn.type(superklass)->is_klassptr()->klass();
2890 ciKlass* subk = _gvn.type(obj)->is_oopptr()->klass();
2891 if (subk != NULL && subk->is_loaded()) {
2892 int static_res = static_subtype_check(superk, subk);
2893 known_statically = (static_res == SSC_always_true || static_res == SSC_always_false);
2894 }
2895 }
2896
2897 if (known_statically && UseTypeSpeculation) {
2898 // If we know the type check always succeeds then we don't use the
2899 // profiling data at this bytecode. Don't lose it, feed it to the
2900 // type system as a speculative type.
2901 not_null_obj = record_profiled_receiver_for_speculation(not_null_obj);
2902 } else {
2903 const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
2904 // We may not have profiling here or it may not help us. If we
2905 // have a speculative type use it to perform an exact cast.
2906 ciKlass* spec_obj_type = obj_type->speculative_type();
2907 if (spec_obj_type != NULL || (ProfileDynamicTypes && data != NULL)) {
2908 Node* cast_obj = maybe_cast_profiled_receiver(not_null_obj, NULL, spec_obj_type, safe_for_replace);
2909 if (stopped()) { // Profile disagrees with this path.
2910 set_control(null_ctl); // Null is the only remaining possibility.
2911 return intcon(0);
2912 }
2913 if (cast_obj != NULL) {
2914 not_null_obj = cast_obj;
2915 }
2916 }
2917 }
2918
2919 // Load the object's klass
2920 Node* obj_klass = load_object_klass(not_null_obj);
2921
2922 // Generate the subtype check
2923 Node* not_subtype_ctrl = gen_subtype_check(obj_klass, superklass);
2924
2925 // Plug in the success path to the general merge in slot 1.
2926 region->init_req(_obj_path, control());
2927 phi ->init_req(_obj_path, intcon(1));
2928
2929 // Plug in the failing path to the general merge in slot 2.
2930 region->init_req(_fail_path, not_subtype_ctrl);
2931 phi ->init_req(_fail_path, intcon(0));
2932
2933 // Return final merged results
2934 set_control( _gvn.transform(region) );
2935 record_for_igvn(region);
2936 return _gvn.transform(phi);
2937 }
2938
2939 //-------------------------------gen_checkcast---------------------------------
2940 // Generate a checkcast idiom. Used by both the checkcast bytecode and the
2941 // array store bytecode. Stack must be as-if BEFORE doing the bytecode so the
2942 // uncommon-trap paths work. Adjust stack after this call.
2943 // If failure_control is supplied and not null, it is filled in with
2944 // the control edge for the cast failure. Otherwise, an appropriate
2945 // uncommon trap or exception is thrown.
2946 Node* GraphKit::gen_checkcast(Node *obj, Node* superklass,
2947 Node* *failure_control) {
2948 kill_dead_locals(); // Benefit all the uncommon traps
2949 const TypeKlassPtr *tk = _gvn.type(superklass)->is_klassptr();
2950 const Type *toop = TypeOopPtr::make_from_klass(tk->klass());
2951
2952 // Fast cutout: Check the case that the cast is vacuously true.
2953 // This detects the common cases where the test will short-circuit
2954 // away completely. We do this before we perform the null check,
2955 // because if the test is going to turn into zero code, we don't
2956 // want a residual null check left around. (Causes a slowdown,
2957 // for example, in some objArray manipulations, such as a[i]=a[j].)
2958 if (tk->singleton()) {
2959 const TypeOopPtr* objtp = _gvn.type(obj)->isa_oopptr();
2960 if (objtp != NULL && objtp->klass() != NULL) {
2961 switch (static_subtype_check(tk->klass(), objtp->klass())) {
2962 case SSC_always_true:
2963 // If we know the type check always succeed then we don't use
2964 // the profiling data at this bytecode. Don't lose it, feed it
2965 // to the type system as a speculative type.
2966 return record_profiled_receiver_for_speculation(obj);
2967 case SSC_always_false:
2968 // It needs a null check because a null will *pass* the cast check.
2969 // A non-null value will always produce an exception.
2970 return null_assert(obj);
2971 }
2972 }
2973 }
2974
2975 ciProfileData* data = NULL;
2976 bool safe_for_replace = false;
2977 if (failure_control == NULL) { // use MDO in regular case only
2978 assert(java_bc() == Bytecodes::_aastore ||
2979 java_bc() == Bytecodes::_checkcast,
2980 "interpreter profiles type checks only for these BCs");
2981 data = method()->method_data()->bci_to_data(bci());
2982 safe_for_replace = true;
2983 }
2984
2985 // Make the merge point
2986 enum { _obj_path = 1, _null_path, PATH_LIMIT };
2987 RegionNode* region = new (C) RegionNode(PATH_LIMIT);
2988 Node* phi = new (C) PhiNode(region, toop);
2989 C->set_has_split_ifs(true); // Has chance for split-if optimization
2990
2991 // Use null-cast information if it is available
2992 bool never_see_null = ((failure_control == NULL) // regular case only
2993 && seems_never_null(obj, data));
2994
2995 // Null check; get casted pointer; set region slot 3
2996 Node* null_ctl = top();
2997 Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace);
2998
2999 // If not_null_obj is dead, only null-path is taken
3000 if (stopped()) { // Doing instance-of on a NULL?
3001 set_control(null_ctl);
3002 return null();
3003 }
3004 region->init_req(_null_path, null_ctl);
3005 phi ->init_req(_null_path, null()); // Set null path value
3006 if (null_ctl == top()) {
3007 // Do this eagerly, so that pattern matches like is_diamond_phi
3008 // will work even during parsing.
3009 assert(_null_path == PATH_LIMIT-1, "delete last");
3010 region->del_req(_null_path);
3011 phi ->del_req(_null_path);
3012 }
3013
3014 Node* cast_obj = NULL;
3015 if (tk->klass_is_exact()) {
3016 // The following optimization tries to statically cast the speculative type of the object
3017 // (for example obtained during profiling) to the type of the superklass and then do a
3018 // dynamic check that the type of the object is what we expect. To work correctly
3019 // for checkcast and aastore the type of superklass should be exact.
3020 const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
3021 // We may not have profiling here or it may not help us. If we have
3022 // a speculative type use it to perform an exact cast.
3023 ciKlass* spec_obj_type = obj_type->speculative_type();
3024 if (spec_obj_type != NULL ||
3025 (data != NULL &&
3026 // Counter has never been decremented (due to cast failure).
3027 // ...This is a reasonable thing to expect. It is true of
3028 // all casts inserted by javac to implement generic types.
3029 data->as_CounterData()->count() >= 0)) {
3030 cast_obj = maybe_cast_profiled_receiver(not_null_obj, tk->klass(), spec_obj_type, safe_for_replace);
3031 if (cast_obj != NULL) {
3032 if (failure_control != NULL) // failure is now impossible
3033 (*failure_control) = top();
3034 // adjust the type of the phi to the exact klass:
3035 phi->raise_bottom_type(_gvn.type(cast_obj)->meet_speculative(TypePtr::NULL_PTR));
3036 }
3037 }
3038 }
3039
3040 if (cast_obj == NULL) {
3041 // Load the object's klass
3042 Node* obj_klass = load_object_klass(not_null_obj);
3043
3044 // Generate the subtype check
3045 Node* not_subtype_ctrl = gen_subtype_check( obj_klass, superklass );
3046
3047 // Plug in success path into the merge
3048 cast_obj = _gvn.transform(new (C) CheckCastPPNode(control(),
3049 not_null_obj, toop));
3050 // Failure path ends in uncommon trap (or may be dead - failure impossible)
3051 if (failure_control == NULL) {
3052 if (not_subtype_ctrl != top()) { // If failure is possible
3053 PreserveJVMState pjvms(this);
3054 set_control(not_subtype_ctrl);
3055 builtin_throw(Deoptimization::Reason_class_check, obj_klass);
3056 }
3057 } else {
3058 (*failure_control) = not_subtype_ctrl;
3059 }
3060 }
3061
3062 region->init_req(_obj_path, control());
3063 phi ->init_req(_obj_path, cast_obj);
3064
3065 // A merge of NULL or Casted-NotNull obj
3066 Node* res = _gvn.transform(phi);
3067
3068 // Note I do NOT always 'replace_in_map(obj,result)' here.
3069 // if( tk->klass()->can_be_primary_super() )
3070 // This means that if I successfully store an Object into an array-of-String
3071 // I 'forget' that the Object is really now known to be a String. I have to
3072 // do this because we don't have true union types for interfaces - if I store
3073 // a Baz into an array-of-Interface and then tell the optimizer it's an
3074 // Interface, I forget that it's also a Baz and cannot do Baz-like field
3075 // references to it. FIX THIS WHEN UNION TYPES APPEAR!
3076 // replace_in_map( obj, res );
3077
3078 // Return final merged results
3079 set_control( _gvn.transform(region) );
3080 record_for_igvn(region);
3081 return res;
3082 }
3083
3084 //------------------------------next_monitor-----------------------------------
3085 // What number should be given to the next monitor?
3086 int GraphKit::next_monitor() {
3087 int current = jvms()->monitor_depth()* C->sync_stack_slots();
3088 int next = current + C->sync_stack_slots();
3089 // Keep the toplevel high water mark current:
3090 if (C->fixed_slots() < next) C->set_fixed_slots(next);
3091 return current;
3092 }
3093
3094 //------------------------------insert_mem_bar---------------------------------
3095 // Memory barrier to avoid floating things around
3096 // The membar serves as a pinch point between both control and all memory slices.
3097 Node* GraphKit::insert_mem_bar(int opcode, Node* precedent) {
3098 MemBarNode* mb = MemBarNode::make(C, opcode, Compile::AliasIdxBot, precedent);
3099 mb->init_req(TypeFunc::Control, control());
3100 mb->init_req(TypeFunc::Memory, reset_memory());
3101 Node* membar = _gvn.transform(mb);
3102 set_control(_gvn.transform(new (C) ProjNode(membar, TypeFunc::Control)));
3103 set_all_memory_call(membar);
3104 return membar;
3105 }
3106
3107 //-------------------------insert_mem_bar_volatile----------------------------
3108 // Memory barrier to avoid floating things around
3109 // The membar serves as a pinch point between both control and memory(alias_idx).
3110 // If you want to make a pinch point on all memory slices, do not use this
3111 // function (even with AliasIdxBot); use insert_mem_bar() instead.
3112 Node* GraphKit::insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent) {
3113 // When Parse::do_put_xxx updates a volatile field, it appends a series
3114 // of MemBarVolatile nodes, one for *each* volatile field alias category.
3115 // The first membar is on the same memory slice as the field store opcode.
3116 // This forces the membar to follow the store. (Bug 6500685 broke this.)
3117 // All the other membars (for other volatile slices, including AliasIdxBot,
3118 // which stands for all unknown volatile slices) are control-dependent
3119 // on the first membar. This prevents later volatile loads or stores
3120 // from sliding up past the just-emitted store.
3121
3122 MemBarNode* mb = MemBarNode::make(C, opcode, alias_idx, precedent);
3123 mb->set_req(TypeFunc::Control,control());
3124 if (alias_idx == Compile::AliasIdxBot) {
3125 mb->set_req(TypeFunc::Memory, merged_memory()->base_memory());
3126 } else {
3127 assert(!(opcode == Op_Initialize && alias_idx != Compile::AliasIdxRaw), "fix caller");
3128 mb->set_req(TypeFunc::Memory, memory(alias_idx));
3129 }
3130 Node* membar = _gvn.transform(mb);
3131 set_control(_gvn.transform(new (C) ProjNode(membar, TypeFunc::Control)));
3132 if (alias_idx == Compile::AliasIdxBot) {
3133 merged_memory()->set_base_memory(_gvn.transform(new (C) ProjNode(membar, TypeFunc::Memory)));
3134 } else {
3135 set_memory(_gvn.transform(new (C) ProjNode(membar, TypeFunc::Memory)),alias_idx);
3136 }
3137 return membar;
3138 }
3139
3140 //------------------------------shared_lock------------------------------------
3141 // Emit locking code.
3142 FastLockNode* GraphKit::shared_lock(Node* obj) {
3143 // bci is either a monitorenter bc or InvocationEntryBci
3144 // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3145 assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3146
3147 if( !GenerateSynchronizationCode )
3148 return NULL; // Not locking things?
3149 if (stopped()) // Dead monitor?
3150 return NULL;
3151
3152 assert(dead_locals_are_killed(), "should kill locals before sync. point");
3153
3154 // Box the stack location
3155 Node* box = _gvn.transform(new (C) BoxLockNode(next_monitor()));
3156 Node* mem = reset_memory();
3157
3158 FastLockNode * flock = _gvn.transform(new (C) FastLockNode(0, obj, box) )->as_FastLock();
3159 if (PrintPreciseBiasedLockingStatistics) {
3160 // Create the counters for this fast lock.
3161 flock->create_lock_counter(sync_jvms()); // sync_jvms used to get current bci
3162 }
3163 // Add monitor to debug info for the slow path. If we block inside the
3164 // slow path and de-opt, we need the monitor hanging around
3165 map()->push_monitor( flock );
3166
3167 const TypeFunc *tf = LockNode::lock_type();
3168 LockNode *lock = new (C) LockNode(C, tf);
3169
3170 lock->init_req( TypeFunc::Control, control() );
3171 lock->init_req( TypeFunc::Memory , mem );
3172 lock->init_req( TypeFunc::I_O , top() ) ; // does no i/o
3173 lock->init_req( TypeFunc::FramePtr, frameptr() );
3174 lock->init_req( TypeFunc::ReturnAdr, top() );
3175
3176 lock->init_req(TypeFunc::Parms + 0, obj);
3177 lock->init_req(TypeFunc::Parms + 1, box);
3178 lock->init_req(TypeFunc::Parms + 2, flock);
3179 add_safepoint_edges(lock);
3180
3181 lock = _gvn.transform( lock )->as_Lock();
3182
3183 // lock has no side-effects, sets few values
3184 set_predefined_output_for_runtime_call(lock, mem, TypeRawPtr::BOTTOM);
3185
3186 insert_mem_bar(Op_MemBarAcquireLock);
3187
3188 // Add this to the worklist so that the lock can be eliminated
3189 record_for_igvn(lock);
3190
3191 #ifndef PRODUCT
3192 if (PrintLockStatistics) {
3193 // Update the counter for this lock. Don't bother using an atomic
3194 // operation since we don't require absolute accuracy.
3195 lock->create_lock_counter(map()->jvms());
3196 increment_counter(lock->counter()->addr());
3197 }
3198 #endif
3199
3200 return flock;
3201 }
3202
3203
3204 //------------------------------shared_unlock----------------------------------
3205 // Emit unlocking code.
3206 void GraphKit::shared_unlock(Node* box, Node* obj) {
3207 // bci is either a monitorenter bc or InvocationEntryBci
3208 // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3209 assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3210
3211 if( !GenerateSynchronizationCode )
3212 return;
3213 if (stopped()) { // Dead monitor?
3214 map()->pop_monitor(); // Kill monitor from debug info
3215 return;
3216 }
3217
3218 // Memory barrier to avoid floating things down past the locked region
3219 insert_mem_bar(Op_MemBarReleaseLock);
3220
3221 const TypeFunc *tf = OptoRuntime::complete_monitor_exit_Type();
3222 UnlockNode *unlock = new (C) UnlockNode(C, tf);
3223 uint raw_idx = Compile::AliasIdxRaw;
3224 unlock->init_req( TypeFunc::Control, control() );
3225 unlock->init_req( TypeFunc::Memory , memory(raw_idx) );
3226 unlock->init_req( TypeFunc::I_O , top() ) ; // does no i/o
3227 unlock->init_req( TypeFunc::FramePtr, frameptr() );
3228 unlock->init_req( TypeFunc::ReturnAdr, top() );
3229
3230 unlock->init_req(TypeFunc::Parms + 0, obj);
3231 unlock->init_req(TypeFunc::Parms + 1, box);
3232 unlock = _gvn.transform(unlock)->as_Unlock();
3233
3234 Node* mem = reset_memory();
3235
3236 // unlock has no side-effects, sets few values
3237 set_predefined_output_for_runtime_call(unlock, mem, TypeRawPtr::BOTTOM);
3238
3239 // Kill monitor from debug info
3240 map()->pop_monitor( );
3241 }
3242
3243 //-------------------------------get_layout_helper-----------------------------
3244 // If the given klass is a constant or known to be an array,
3245 // fetch the constant layout helper value into constant_value
3246 // and return (Node*)NULL. Otherwise, load the non-constant
3247 // layout helper value, and return the node which represents it.
3248 // This two-faced routine is useful because allocation sites
3249 // almost always feature constant types.
3250 Node* GraphKit::get_layout_helper(Node* klass_node, jint& constant_value) {
3251 const TypeKlassPtr* inst_klass = _gvn.type(klass_node)->isa_klassptr();
3252 if (!StressReflectiveCode && inst_klass != NULL) {
3253 ciKlass* klass = inst_klass->klass();
3254 bool xklass = inst_klass->klass_is_exact();
3255 if (xklass || klass->is_array_klass()) {
3256 jint lhelper = klass->layout_helper();
3257 if (lhelper != Klass::_lh_neutral_value) {
3258 constant_value = lhelper;
3259 return (Node*) NULL;
3260 }
3261 }
3262 }
3263 constant_value = Klass::_lh_neutral_value; // put in a known value
3264 Node* lhp = basic_plus_adr(klass_node, klass_node, in_bytes(Klass::layout_helper_offset()));
3265 return make_load(NULL, lhp, TypeInt::INT, T_INT, MemNode::unordered);
3266 }
3267
3268 // We just put in an allocate/initialize with a big raw-memory effect.
3269 // Hook selected additional alias categories on the initialization.
3270 static void hook_memory_on_init(GraphKit& kit, int alias_idx,
3271 MergeMemNode* init_in_merge,
3272 Node* init_out_raw) {
3273 DEBUG_ONLY(Node* init_in_raw = init_in_merge->base_memory());
3274 assert(init_in_merge->memory_at(alias_idx) == init_in_raw, "");
3275
3276 Node* prevmem = kit.memory(alias_idx);
3277 init_in_merge->set_memory_at(alias_idx, prevmem);
3278 kit.set_memory(init_out_raw, alias_idx);
3279 }
3280
3281 //---------------------------set_output_for_allocation-------------------------
3282 Node* GraphKit::set_output_for_allocation(AllocateNode* alloc,
3283 const TypeOopPtr* oop_type) {
3284 int rawidx = Compile::AliasIdxRaw;
3285 alloc->set_req( TypeFunc::FramePtr, frameptr() );
3286 add_safepoint_edges(alloc);
3287 Node* allocx = _gvn.transform(alloc);
3288 set_control( _gvn.transform(new (C) ProjNode(allocx, TypeFunc::Control) ) );
3289 // create memory projection for i_o
3290 set_memory ( _gvn.transform( new (C) ProjNode(allocx, TypeFunc::Memory, true) ), rawidx );
3291 make_slow_call_ex(allocx, env()->Throwable_klass(), true);
3292
3293 // create a memory projection as for the normal control path
3294 Node* malloc = _gvn.transform(new (C) ProjNode(allocx, TypeFunc::Memory));
3295 set_memory(malloc, rawidx);
3296
3297 // a normal slow-call doesn't change i_o, but an allocation does
3298 // we create a separate i_o projection for the normal control path
3299 set_i_o(_gvn.transform( new (C) ProjNode(allocx, TypeFunc::I_O, false) ) );
3300 Node* rawoop = _gvn.transform( new (C) ProjNode(allocx, TypeFunc::Parms) );
3301
3302 // put in an initialization barrier
3303 InitializeNode* init = insert_mem_bar_volatile(Op_Initialize, rawidx,
3304 rawoop)->as_Initialize();
3305 assert(alloc->initialization() == init, "2-way macro link must work");
3306 assert(init ->allocation() == alloc, "2-way macro link must work");
3307 {
3308 // Extract memory strands which may participate in the new object's
3309 // initialization, and source them from the new InitializeNode.
3310 // This will allow us to observe initializations when they occur,
3311 // and link them properly (as a group) to the InitializeNode.
3312 assert(init->in(InitializeNode::Memory) == malloc, "");
3313 MergeMemNode* minit_in = MergeMemNode::make(C, malloc);
3314 init->set_req(InitializeNode::Memory, minit_in);
3315 record_for_igvn(minit_in); // fold it up later, if possible
3316 Node* minit_out = memory(rawidx);
3317 assert(minit_out->is_Proj() && minit_out->in(0) == init, "");
3318 if (oop_type->isa_aryptr()) {
3319 const TypePtr* telemref = oop_type->add_offset(Type::OffsetBot);
3320 int elemidx = C->get_alias_index(telemref);
3321 hook_memory_on_init(*this, elemidx, minit_in, minit_out);
3322 } else if (oop_type->isa_instptr()) {
3323 ciInstanceKlass* ik = oop_type->klass()->as_instance_klass();
3324 for (int i = 0, len = ik->nof_nonstatic_fields(); i < len; i++) {
3325 ciField* field = ik->nonstatic_field_at(i);
3326 if (field->offset() >= TrackedInitializationLimit * HeapWordSize)
3327 continue; // do not bother to track really large numbers of fields
3328 // Find (or create) the alias category for this field:
3329 int fieldidx = C->alias_type(field)->index();
3330 hook_memory_on_init(*this, fieldidx, minit_in, minit_out);
3331 }
3332 }
3333 }
3334
3335 // Cast raw oop to the real thing...
3336 Node* javaoop = new (C) CheckCastPPNode(control(), rawoop, oop_type);
3337 javaoop = _gvn.transform(javaoop);
3338 C->set_recent_alloc(control(), javaoop);
3339 assert(just_allocated_object(control()) == javaoop, "just allocated");
3340
3341 #ifdef ASSERT
3342 { // Verify that the AllocateNode::Ideal_allocation recognizers work:
3343 assert(AllocateNode::Ideal_allocation(rawoop, &_gvn) == alloc,
3344 "Ideal_allocation works");
3345 assert(AllocateNode::Ideal_allocation(javaoop, &_gvn) == alloc,
3346 "Ideal_allocation works");
3347 if (alloc->is_AllocateArray()) {
3348 assert(AllocateArrayNode::Ideal_array_allocation(rawoop, &_gvn) == alloc->as_AllocateArray(),
3349 "Ideal_allocation works");
3350 assert(AllocateArrayNode::Ideal_array_allocation(javaoop, &_gvn) == alloc->as_AllocateArray(),
3351 "Ideal_allocation works");
3352 } else {
3353 assert(alloc->in(AllocateNode::ALength)->is_top(), "no length, please");
3354 }
3355 }
3356 #endif //ASSERT
3357
3358 return javaoop;
3359 }
3360
3361 //---------------------------new_instance--------------------------------------
3362 // This routine takes a klass_node which may be constant (for a static type)
3363 // or may be non-constant (for reflective code). It will work equally well
3364 // for either, and the graph will fold nicely if the optimizer later reduces
3365 // the type to a constant.
3366 // The optional arguments are for specialized use by intrinsics:
3367 // - If 'extra_slow_test' if not null is an extra condition for the slow-path.
3368 // - If 'return_size_val', report the the total object size to the caller.
3369 Node* GraphKit::new_instance(Node* klass_node,
3370 Node* extra_slow_test,
3371 Node* *return_size_val) {
3372 // Compute size in doublewords
3373 // The size is always an integral number of doublewords, represented
3374 // as a positive bytewise size stored in the klass's layout_helper.
3375 // The layout_helper also encodes (in a low bit) the need for a slow path.
3376 jint layout_con = Klass::_lh_neutral_value;
3377 Node* layout_val = get_layout_helper(klass_node, layout_con);
3378 int layout_is_con = (layout_val == NULL);
3379
3380 if (extra_slow_test == NULL) extra_slow_test = intcon(0);
3381 // Generate the initial go-slow test. It's either ALWAYS (return a
3382 // Node for 1) or NEVER (return a NULL) or perhaps (in the reflective
3383 // case) a computed value derived from the layout_helper.
3384 Node* initial_slow_test = NULL;
3385 if (layout_is_con) {
3386 assert(!StressReflectiveCode, "stress mode does not use these paths");
3387 bool must_go_slow = Klass::layout_helper_needs_slow_path(layout_con);
3388 initial_slow_test = must_go_slow? intcon(1): extra_slow_test;
3389
3390 } else { // reflective case
3391 // This reflective path is used by Unsafe.allocateInstance.
3392 // (It may be stress-tested by specifying StressReflectiveCode.)
3393 // Basically, we want to get into the VM is there's an illegal argument.
3394 Node* bit = intcon(Klass::_lh_instance_slow_path_bit);
3395 initial_slow_test = _gvn.transform( new (C) AndINode(layout_val, bit) );
3396 if (extra_slow_test != intcon(0)) {
3397 initial_slow_test = _gvn.transform( new (C) OrINode(initial_slow_test, extra_slow_test) );
3398 }
3399 // (Macro-expander will further convert this to a Bool, if necessary.)
3400 }
3401
3402 // Find the size in bytes. This is easy; it's the layout_helper.
3403 // The size value must be valid even if the slow path is taken.
3404 Node* size = NULL;
3405 if (layout_is_con) {
3406 size = MakeConX(Klass::layout_helper_size_in_bytes(layout_con));
3407 } else { // reflective case
3408 // This reflective path is used by clone and Unsafe.allocateInstance.
3409 size = ConvI2X(layout_val);
3410
3411 // Clear the low bits to extract layout_helper_size_in_bytes:
3412 assert((int)Klass::_lh_instance_slow_path_bit < BytesPerLong, "clear bit");
3413 Node* mask = MakeConX(~ (intptr_t)right_n_bits(LogBytesPerLong));
3414 size = _gvn.transform( new (C) AndXNode(size, mask) );
3415 }
3416 if (return_size_val != NULL) {
3417 (*return_size_val) = size;
3418 }
3419
3420 // This is a precise notnull oop of the klass.
3421 // (Actually, it need not be precise if this is a reflective allocation.)
3422 // It's what we cast the result to.
3423 const TypeKlassPtr* tklass = _gvn.type(klass_node)->isa_klassptr();
3424 if (!tklass) tklass = TypeKlassPtr::OBJECT;
3425 const TypeOopPtr* oop_type = tklass->as_instance_type();
3426
3427 // Now generate allocation code
3428
3429 // The entire memory state is needed for slow path of the allocation
3430 // since GC and deoptimization can happened.
3431 Node *mem = reset_memory();
3432 set_all_memory(mem); // Create new memory state
3433
3434 AllocateNode* alloc
3435 = new (C) AllocateNode(C, AllocateNode::alloc_type(Type::TOP),
3436 control(), mem, i_o(),
3437 size, klass_node,
3438 initial_slow_test);
3439
3440 return set_output_for_allocation(alloc, oop_type);
3441 }
3442
3443 //-------------------------------new_array-------------------------------------
3444 // helper for both newarray and anewarray
3445 // The 'length' parameter is (obviously) the length of the array.
3446 // See comments on new_instance for the meaning of the other arguments.
3447 Node* GraphKit::new_array(Node* klass_node, // array klass (maybe variable)
3448 Node* length, // number of array elements
3449 int nargs, // number of arguments to push back for uncommon trap
3450 Node* *return_size_val) {
3451 jint layout_con = Klass::_lh_neutral_value;
3452 Node* layout_val = get_layout_helper(klass_node, layout_con);
3453 int layout_is_con = (layout_val == NULL);
3454
3455 if (!layout_is_con && !StressReflectiveCode &&
3456 !too_many_traps(Deoptimization::Reason_class_check)) {
3457 // This is a reflective array creation site.
3458 // Optimistically assume that it is a subtype of Object[],
3459 // so that we can fold up all the address arithmetic.
3460 layout_con = Klass::array_layout_helper(T_OBJECT);
3461 Node* cmp_lh = _gvn.transform( new(C) CmpINode(layout_val, intcon(layout_con)) );
3462 Node* bol_lh = _gvn.transform( new(C) BoolNode(cmp_lh, BoolTest::eq) );
3463 { BuildCutout unless(this, bol_lh, PROB_MAX);
3464 inc_sp(nargs);
3465 uncommon_trap(Deoptimization::Reason_class_check,
3466 Deoptimization::Action_maybe_recompile);
3467 }
3468 layout_val = NULL;
3469 layout_is_con = true;
3470 }
3471
3472 // Generate the initial go-slow test. Make sure we do not overflow
3473 // if length is huge (near 2Gig) or negative! We do not need
3474 // exact double-words here, just a close approximation of needed
3475 // double-words. We can't add any offset or rounding bits, lest we
3476 // take a size -1 of bytes and make it positive. Use an unsigned
3477 // compare, so negative sizes look hugely positive.
3478 int fast_size_limit = FastAllocateSizeLimit;
3479 if (layout_is_con) {
3480 assert(!StressReflectiveCode, "stress mode does not use these paths");
3481 // Increase the size limit if we have exact knowledge of array type.
3482 int log2_esize = Klass::layout_helper_log2_element_size(layout_con);
3483 fast_size_limit <<= (LogBytesPerLong - log2_esize);
3484 }
3485
3486 Node* initial_slow_cmp = _gvn.transform( new (C) CmpUNode( length, intcon( fast_size_limit ) ) );
3487 Node* initial_slow_test = _gvn.transform( new (C) BoolNode( initial_slow_cmp, BoolTest::gt ) );
3488 if (initial_slow_test->is_Bool()) {
3489 // Hide it behind a CMoveI, or else PhaseIdealLoop::split_up will get sick.
3490 initial_slow_test = initial_slow_test->as_Bool()->as_int_value(&_gvn);
3491 }
3492
3493 // --- Size Computation ---
3494 // array_size = round_to_heap(array_header + (length << elem_shift));
3495 // where round_to_heap(x) == round_to(x, MinObjAlignmentInBytes)
3496 // and round_to(x, y) == ((x + y-1) & ~(y-1))
3497 // The rounding mask is strength-reduced, if possible.
3498 int round_mask = MinObjAlignmentInBytes - 1;
3499 Node* header_size = NULL;
3500 int header_size_min = arrayOopDesc::base_offset_in_bytes(T_BYTE);
3501 // (T_BYTE has the weakest alignment and size restrictions...)
3502 if (layout_is_con) {
3503 int hsize = Klass::layout_helper_header_size(layout_con);
3504 int eshift = Klass::layout_helper_log2_element_size(layout_con);
3505 BasicType etype = Klass::layout_helper_element_type(layout_con);
3506 if ((round_mask & ~right_n_bits(eshift)) == 0)
3507 round_mask = 0; // strength-reduce it if it goes away completely
3508 assert((hsize & right_n_bits(eshift)) == 0, "hsize is pre-rounded");
3509 assert(header_size_min <= hsize, "generic minimum is smallest");
3510 header_size_min = hsize;
3511 header_size = intcon(hsize + round_mask);
3512 } else {
3513 Node* hss = intcon(Klass::_lh_header_size_shift);
3514 Node* hsm = intcon(Klass::_lh_header_size_mask);
3515 Node* hsize = _gvn.transform( new(C) URShiftINode(layout_val, hss) );
3516 hsize = _gvn.transform( new(C) AndINode(hsize, hsm) );
3517 Node* mask = intcon(round_mask);
3518 header_size = _gvn.transform( new(C) AddINode(hsize, mask) );
3519 }
3520
3521 Node* elem_shift = NULL;
3522 if (layout_is_con) {
3523 int eshift = Klass::layout_helper_log2_element_size(layout_con);
3524 if (eshift != 0)
3525 elem_shift = intcon(eshift);
3526 } else {
3527 // There is no need to mask or shift this value.
3528 // The semantics of LShiftINode include an implicit mask to 0x1F.
3529 assert(Klass::_lh_log2_element_size_shift == 0, "use shift in place");
3530 elem_shift = layout_val;
3531 }
3532
3533 // Transition to native address size for all offset calculations:
3534 Node* lengthx = ConvI2X(length);
3535 Node* headerx = ConvI2X(header_size);
3536 #ifdef _LP64
3537 { const TypeLong* tllen = _gvn.find_long_type(lengthx);
3538 if (tllen != NULL && tllen->_lo < 0) {
3539 // Add a manual constraint to a positive range. Cf. array_element_address.
3540 jlong size_max = arrayOopDesc::max_array_length(T_BYTE);
3541 if (size_max > tllen->_hi) size_max = tllen->_hi;
3542 const TypeLong* tlcon = TypeLong::make(CONST64(0), size_max, Type::WidenMin);
3543 lengthx = _gvn.transform( new (C) ConvI2LNode(length, tlcon));
3544 }
3545 }
3546 #endif
3547
3548 // Combine header size (plus rounding) and body size. Then round down.
3549 // This computation cannot overflow, because it is used only in two
3550 // places, one where the length is sharply limited, and the other
3551 // after a successful allocation.
3552 Node* abody = lengthx;
3553 if (elem_shift != NULL)
3554 abody = _gvn.transform( new(C) LShiftXNode(lengthx, elem_shift) );
3555 Node* size = _gvn.transform( new(C) AddXNode(headerx, abody) );
3556 if (round_mask != 0) {
3557 Node* mask = MakeConX(~round_mask);
3558 size = _gvn.transform( new(C) AndXNode(size, mask) );
3559 }
3560 // else if round_mask == 0, the size computation is self-rounding
3561
3562 if (return_size_val != NULL) {
3563 // This is the size
3564 (*return_size_val) = size;
3565 }
3566
3567 // Now generate allocation code
3568
3569 // The entire memory state is needed for slow path of the allocation
3570 // since GC and deoptimization can happened.
3571 Node *mem = reset_memory();
3572 set_all_memory(mem); // Create new memory state
3573
3574 // Create the AllocateArrayNode and its result projections
3575 AllocateArrayNode* alloc
3576 = new (C) AllocateArrayNode(C, AllocateArrayNode::alloc_type(TypeInt::INT),
3577 control(), mem, i_o(),
3578 size, klass_node,
3579 initial_slow_test,
3580 length);
3581
3582 // Cast to correct type. Note that the klass_node may be constant or not,
3583 // and in the latter case the actual array type will be inexact also.
3584 // (This happens via a non-constant argument to inline_native_newArray.)
3585 // In any case, the value of klass_node provides the desired array type.
3586 const TypeInt* length_type = _gvn.find_int_type(length);
3587 const TypeOopPtr* ary_type = _gvn.type(klass_node)->is_klassptr()->as_instance_type();
3588 if (ary_type->isa_aryptr() && length_type != NULL) {
3589 // Try to get a better type than POS for the size
3590 ary_type = ary_type->is_aryptr()->cast_to_size(length_type);
3591 }
3592
3593 Node* javaoop = set_output_for_allocation(alloc, ary_type);
3594
3595 // Cast length on remaining path to be as narrow as possible
3596 if (map()->find_edge(length) >= 0) {
3597 Node* ccast = alloc->make_ideal_length(ary_type, &_gvn);
3598 if (ccast != length) {
3599 _gvn.set_type_bottom(ccast);
3600 record_for_igvn(ccast);
3601 replace_in_map(length, ccast);
3602 }
3603 }
3604
3605 return javaoop;
3606 }
3607
3608 // The following "Ideal_foo" functions are placed here because they recognize
3609 // the graph shapes created by the functions immediately above.
3610
3611 //---------------------------Ideal_allocation----------------------------------
3612 // Given an oop pointer or raw pointer, see if it feeds from an AllocateNode.
3613 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase) {
3614 if (ptr == NULL) { // reduce dumb test in callers
3615 return NULL;
3616 }
3617 if (ptr->is_CheckCastPP()) { // strip only one raw-to-oop cast
3618 ptr = ptr->in(1);
3619 if (ptr == NULL) return NULL;
3620 }
3621 // Return NULL for allocations with several casts:
3622 // j.l.reflect.Array.newInstance(jobject, jint)
3623 // Object.clone()
3624 // to keep more precise type from last cast.
3625 if (ptr->is_Proj()) {
3626 Node* allo = ptr->in(0);
3627 if (allo != NULL && allo->is_Allocate()) {
3628 return allo->as_Allocate();
3629 }
3630 }
3631 // Report failure to match.
3632 return NULL;
3633 }
3634
3635 // Fancy version which also strips off an offset (and reports it to caller).
3636 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase,
3637 intptr_t& offset) {
3638 Node* base = AddPNode::Ideal_base_and_offset(ptr, phase, offset);
3639 if (base == NULL) return NULL;
3640 return Ideal_allocation(base, phase);
3641 }
3642
3643 // Trace Initialize <- Proj[Parm] <- Allocate
3644 AllocateNode* InitializeNode::allocation() {
3645 Node* rawoop = in(InitializeNode::RawAddress);
3646 if (rawoop->is_Proj()) {
3647 Node* alloc = rawoop->in(0);
3648 if (alloc->is_Allocate()) {
3649 return alloc->as_Allocate();
3650 }
3651 }
3652 return NULL;
3653 }
3654
3655 // Trace Allocate -> Proj[Parm] -> Initialize
3656 InitializeNode* AllocateNode::initialization() {
3657 ProjNode* rawoop = proj_out(AllocateNode::RawAddress);
3658 if (rawoop == NULL) return NULL;
3659 for (DUIterator_Fast imax, i = rawoop->fast_outs(imax); i < imax; i++) {
3660 Node* init = rawoop->fast_out(i);
3661 if (init->is_Initialize()) {
3662 assert(init->as_Initialize()->allocation() == this, "2-way link");
3663 return init->as_Initialize();
3664 }
3665 }
3666 return NULL;
3667 }
3668
3669 //----------------------------- loop predicates ---------------------------
3670
3671 //------------------------------add_predicate_impl----------------------------
3672 void GraphKit::add_predicate_impl(Deoptimization::DeoptReason reason, int nargs) {
3673 // Too many traps seen?
3674 if (too_many_traps(reason)) {
3675 #ifdef ASSERT
3676 if (TraceLoopPredicate) {
3677 int tc = C->trap_count(reason);
3678 tty->print("too many traps=%s tcount=%d in ",
3679 Deoptimization::trap_reason_name(reason), tc);
3680 method()->print(); // which method has too many predicate traps
3681 tty->cr();
3682 }
3683 #endif
3684 // We cannot afford to take more traps here,
3685 // do not generate predicate.
3686 return;
3687 }
3688
3689 Node *cont = _gvn.intcon(1);
3690 Node* opq = _gvn.transform(new (C) Opaque1Node(C, cont));
3691 Node *bol = _gvn.transform(new (C) Conv2BNode(opq));
3692 IfNode* iff = create_and_map_if(control(), bol, PROB_MAX, COUNT_UNKNOWN);
3693 Node* iffalse = _gvn.transform(new (C) IfFalseNode(iff));
3694 C->add_predicate_opaq(opq);
3695 {
3696 PreserveJVMState pjvms(this);
3697 set_control(iffalse);
3698 inc_sp(nargs);
3699 uncommon_trap(reason, Deoptimization::Action_maybe_recompile);
3700 }
3701 Node* iftrue = _gvn.transform(new (C) IfTrueNode(iff));
3702 set_control(iftrue);
3703 }
3704
3705 //------------------------------add_predicate---------------------------------
3706 void GraphKit::add_predicate(int nargs) {
3707 if (UseLoopPredicate) {
3708 add_predicate_impl(Deoptimization::Reason_predicate, nargs);
3709 }
3710 // loop's limit check predicate should be near the loop.
3711 if (LoopLimitCheck) {
3712 add_predicate_impl(Deoptimization::Reason_loop_limit_check, nargs);
3713 }
3714 }
3715
3716 //----------------------------- store barriers ----------------------------
3717 #define __ ideal.
3718
3719 void GraphKit::sync_kit(IdealKit& ideal) {
3720 set_all_memory(__ merged_memory());
3721 set_i_o(__ i_o());
3722 set_control(__ ctrl());
3723 }
3724
3725 void GraphKit::final_sync(IdealKit& ideal) {
3726 // Final sync IdealKit and graphKit.
3727 sync_kit(ideal);
3728 }
3729
3730 // vanilla/CMS post barrier
3731 // Insert a write-barrier store. This is to let generational GC work; we have
3732 // to flag all oop-stores before the next GC point.
3733 void GraphKit::write_barrier_post(Node* oop_store,
3734 Node* obj,
3735 Node* adr,
3736 uint adr_idx,
3737 Node* val,
3738 bool use_precise) {
3739 // No store check needed if we're storing a NULL or an old object
3740 // (latter case is probably a string constant). The concurrent
3741 // mark sweep garbage collector, however, needs to have all nonNull
3742 // oop updates flagged via card-marks.
3743 if (val != NULL && val->is_Con()) {
3744 // must be either an oop or NULL
3745 const Type* t = val->bottom_type();
3746 if (t == TypePtr::NULL_PTR || t == Type::TOP)
3747 // stores of null never (?) need barriers
3748 return;
3749 }
3750
3751 if (use_ReduceInitialCardMarks()
3752 && obj == just_allocated_object(control())) {
3753 // We can skip marks on a freshly-allocated object in Eden.
3754 // Keep this code in sync with new_store_pre_barrier() in runtime.cpp.
3755 // That routine informs GC to take appropriate compensating steps,
3756 // upon a slow-path allocation, so as to make this card-mark
3757 // elision safe.
3758 return;
3759 }
3760
3761 if (!use_precise) {
3762 // All card marks for a (non-array) instance are in one place:
3763 adr = obj;
3764 }
3765 // (Else it's an array (or unknown), and we want more precise card marks.)
3766 assert(adr != NULL, "");
3767
3768 IdealKit ideal(this, true);
3769
3770 // Convert the pointer to an int prior to doing math on it
3771 Node* cast = __ CastPX(__ ctrl(), adr);
3772
3773 // Divide by card size
3774 assert(Universe::heap()->barrier_set()->kind() == BarrierSet::CardTableModRef,
3775 "Only one we handle so far.");
3776 Node* card_offset = __ URShiftX( cast, __ ConI(CardTableModRefBS::card_shift) );
3777
3778 // Combine card table base and card offset
3779 Node* card_adr = __ AddP(__ top(), byte_map_base_node(), card_offset );
3780
3781 // Get the alias_index for raw card-mark memory
3782 int adr_type = Compile::AliasIdxRaw;
3783 Node* zero = __ ConI(0); // Dirty card value
3784 BasicType bt = T_BYTE;
3785
3786 if (UseCondCardMark) {
3787 // The classic GC reference write barrier is typically implemented
3788 // as a store into the global card mark table. Unfortunately
3789 // unconditional stores can result in false sharing and excessive
3790 // coherence traffic as well as false transactional aborts.
3791 // UseCondCardMark enables MP "polite" conditional card mark
3792 // stores. In theory we could relax the load from ctrl() to
3793 // no_ctrl, but that doesn't buy much latitude.
3794 Node* card_val = __ load( __ ctrl(), card_adr, TypeInt::BYTE, bt, adr_type);
3795 __ if_then(card_val, BoolTest::ne, zero);
3796 }
3797
3798 // Smash zero into card
3799 if( !UseConcMarkSweepGC ) {
3800 __ store(__ ctrl(), card_adr, zero, bt, adr_type, MemNode::release);
3801 } else {
3802 // Specialized path for CM store barrier
3803 __ storeCM(__ ctrl(), card_adr, zero, oop_store, adr_idx, bt, adr_type);
3804 }
3805
3806 if (UseCondCardMark) {
3807 __ end_if();
3808 }
3809
3810 // Final sync IdealKit and GraphKit.
3811 final_sync(ideal);
3812 }
3813
3814 // G1 pre/post barriers
3815 void GraphKit::g1_write_barrier_pre(bool do_load,
3816 Node* obj,
3817 Node* adr,
3818 uint alias_idx,
3819 Node* val,
3820 const TypeOopPtr* val_type,
3821 Node* pre_val,
3822 BasicType bt) {
3823
3824 // Some sanity checks
3825 // Note: val is unused in this routine.
3826
3827 if (do_load) {
3828 // We need to generate the load of the previous value
3829 assert(obj != NULL, "must have a base");
3830 assert(adr != NULL, "where are loading from?");
3831 assert(pre_val == NULL, "loaded already?");
3832 assert(val_type != NULL, "need a type");
3833 } else {
3834 // In this case both val_type and alias_idx are unused.
3835 assert(pre_val != NULL, "must be loaded already");
3836 // Nothing to be done if pre_val is null.
3837 if (pre_val->bottom_type() == TypePtr::NULL_PTR) return;
3838 assert(pre_val->bottom_type()->basic_type() == T_OBJECT, "or we shouldn't be here");
3839 }
3840 assert(bt == T_OBJECT, "or we shouldn't be here");
3841
3842 IdealKit ideal(this, true);
3843
3844 Node* tls = __ thread(); // ThreadLocalStorage
3845
3846 Node* no_ctrl = NULL;
3847 Node* no_base = __ top();
3848 Node* zero = __ ConI(0);
3849 Node* zeroX = __ ConX(0);
3850
3851 float likely = PROB_LIKELY(0.999);
3852 float unlikely = PROB_UNLIKELY(0.999);
3853
3854 BasicType active_type = in_bytes(PtrQueue::byte_width_of_active()) == 4 ? T_INT : T_BYTE;
3855 assert(in_bytes(PtrQueue::byte_width_of_active()) == 4 || in_bytes(PtrQueue::byte_width_of_active()) == 1, "flag width");
3856
3857 // Offsets into the thread
3858 const int marking_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 648
3859 PtrQueue::byte_offset_of_active());
3860 const int index_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 656
3861 PtrQueue::byte_offset_of_index());
3862 const int buffer_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 652
3863 PtrQueue::byte_offset_of_buf());
3864
3865 // Now the actual pointers into the thread
3866 Node* marking_adr = __ AddP(no_base, tls, __ ConX(marking_offset));
3867 Node* buffer_adr = __ AddP(no_base, tls, __ ConX(buffer_offset));
3868 Node* index_adr = __ AddP(no_base, tls, __ ConX(index_offset));
3869
3870 // Now some of the values
3871 Node* marking = __ load(__ ctrl(), marking_adr, TypeInt::INT, active_type, Compile::AliasIdxRaw);
3872
3873 // if (!marking)
3874 __ if_then(marking, BoolTest::ne, zero, unlikely); {
3875 BasicType index_bt = TypeX_X->basic_type();
3876 assert(sizeof(size_t) == type2aelembytes(index_bt), "Loading G1 PtrQueue::_index with wrong size.");
3877 Node* index = __ load(__ ctrl(), index_adr, TypeX_X, index_bt, Compile::AliasIdxRaw);
3878
3879 if (do_load) {
3880 // load original value
3881 // alias_idx correct??
3882 pre_val = __ load(__ ctrl(), adr, val_type, bt, alias_idx);
3883 }
3884
3885 // if (pre_val != NULL)
3886 __ if_then(pre_val, BoolTest::ne, null()); {
3887 Node* buffer = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw);
3888
3889 // is the queue for this thread full?
3890 __ if_then(index, BoolTest::ne, zeroX, likely); {
3891
3892 // decrement the index
3893 Node* next_index = _gvn.transform(new (C) SubXNode(index, __ ConX(sizeof(intptr_t))));
3894
3895 // Now get the buffer location we will log the previous value into and store it
3896 Node *log_addr = __ AddP(no_base, buffer, next_index);
3897 __ store(__ ctrl(), log_addr, pre_val, T_OBJECT, Compile::AliasIdxRaw, MemNode::unordered);
3898 // update the index
3899 __ store(__ ctrl(), index_adr, next_index, index_bt, Compile::AliasIdxRaw, MemNode::unordered);
3900
3901 } __ else_(); {
3902
3903 // logging buffer is full, call the runtime
3904 const TypeFunc *tf = OptoRuntime::g1_wb_pre_Type();
3905 __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_pre), "g1_wb_pre", pre_val, tls);
3906 } __ end_if(); // (!index)
3907 } __ end_if(); // (pre_val != NULL)
3908 } __ end_if(); // (!marking)
3909
3910 // Final sync IdealKit and GraphKit.
3911 final_sync(ideal);
3912 }
3913
3914 //
3915 // Update the card table and add card address to the queue
3916 //
3917 void GraphKit::g1_mark_card(IdealKit& ideal,
3918 Node* card_adr,
3919 Node* oop_store,
3920 uint oop_alias_idx,
3921 Node* index,
3922 Node* index_adr,
3923 Node* buffer,
3924 const TypeFunc* tf) {
3925
3926 Node* zero = __ ConI(0);
3927 Node* zeroX = __ ConX(0);
3928 Node* no_base = __ top();
3929 BasicType card_bt = T_BYTE;
3930 // Smash zero into card. MUST BE ORDERED WRT TO STORE
3931 __ storeCM(__ ctrl(), card_adr, zero, oop_store, oop_alias_idx, card_bt, Compile::AliasIdxRaw);
3932
3933 // Now do the queue work
3934 __ if_then(index, BoolTest::ne, zeroX); {
3935
3936 Node* next_index = _gvn.transform(new (C) SubXNode(index, __ ConX(sizeof(intptr_t))));
3937 Node* log_addr = __ AddP(no_base, buffer, next_index);
3938
3939 // Order, see storeCM.
3940 __ store(__ ctrl(), log_addr, card_adr, T_ADDRESS, Compile::AliasIdxRaw, MemNode::unordered);
3941 __ store(__ ctrl(), index_adr, next_index, TypeX_X->basic_type(), Compile::AliasIdxRaw, MemNode::unordered);
3942
3943 } __ else_(); {
3944 __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_post), "g1_wb_post", card_adr, __ thread());
3945 } __ end_if();
3946
3947 }
3948
3949 void GraphKit::g1_write_barrier_post(Node* oop_store,
3950 Node* obj,
3951 Node* adr,
3952 uint alias_idx,
3953 Node* val,
3954 BasicType bt,
3955 bool use_precise) {
3956 // If we are writing a NULL then we need no post barrier
3957
3958 if (val != NULL && val->is_Con() && val->bottom_type() == TypePtr::NULL_PTR) {
3959 // Must be NULL
3960 const Type* t = val->bottom_type();
3961 assert(t == Type::TOP || t == TypePtr::NULL_PTR, "must be NULL");
3962 // No post barrier if writing NULLx
3963 return;
3964 }
3965
3966 if (!use_precise) {
3967 // All card marks for a (non-array) instance are in one place:
3968 adr = obj;
3969 }
3970 // (Else it's an array (or unknown), and we want more precise card marks.)
3971 assert(adr != NULL, "");
3972
3973 IdealKit ideal(this, true);
3974
3975 Node* tls = __ thread(); // ThreadLocalStorage
3976
3977 Node* no_base = __ top();
3978 float likely = PROB_LIKELY(0.999);
3979 float unlikely = PROB_UNLIKELY(0.999);
3980 Node* young_card = __ ConI((jint)G1SATBCardTableModRefBS::g1_young_card_val());
3981 Node* dirty_card = __ ConI((jint)CardTableModRefBS::dirty_card_val());
3982 Node* zeroX = __ ConX(0);
3983
3984 // Get the alias_index for raw card-mark memory
3985 const TypePtr* card_type = TypeRawPtr::BOTTOM;
3986
3987 const TypeFunc *tf = OptoRuntime::g1_wb_post_Type();
3988
3989 // Offsets into the thread
3990 const int index_offset = in_bytes(JavaThread::dirty_card_queue_offset() +
3991 PtrQueue::byte_offset_of_index());
3992 const int buffer_offset = in_bytes(JavaThread::dirty_card_queue_offset() +
3993 PtrQueue::byte_offset_of_buf());
3994
3995 // Pointers into the thread
3996
3997 Node* buffer_adr = __ AddP(no_base, tls, __ ConX(buffer_offset));
3998 Node* index_adr = __ AddP(no_base, tls, __ ConX(index_offset));
3999
4000 // Now some values
4001 // Use ctrl to avoid hoisting these values past a safepoint, which could
4002 // potentially reset these fields in the JavaThread.
4003 Node* index = __ load(__ ctrl(), index_adr, TypeX_X, TypeX_X->basic_type(), Compile::AliasIdxRaw);
4004 Node* buffer = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw);
4005
4006 // Convert the store obj pointer to an int prior to doing math on it
4007 // Must use ctrl to prevent "integerized oop" existing across safepoint
4008 Node* cast = __ CastPX(__ ctrl(), adr);
4009
4010 // Divide pointer by card size
4011 Node* card_offset = __ URShiftX( cast, __ ConI(CardTableModRefBS::card_shift) );
4012
4013 // Combine card table base and card offset
4014 Node* card_adr = __ AddP(no_base, byte_map_base_node(), card_offset );
4015
4016 // If we know the value being stored does it cross regions?
4017
4018 if (val != NULL) {
4019 // Does the store cause us to cross regions?
4020
4021 // Should be able to do an unsigned compare of region_size instead of
4022 // and extra shift. Do we have an unsigned compare??
4023 // Node* region_size = __ ConI(1 << HeapRegion::LogOfHRGrainBytes);
4024 Node* xor_res = __ URShiftX ( __ XorX( cast, __ CastPX(__ ctrl(), val)), __ ConI(HeapRegion::LogOfHRGrainBytes));
4025
4026 // if (xor_res == 0) same region so skip
4027 __ if_then(xor_res, BoolTest::ne, zeroX); {
4028
4029 // No barrier if we are storing a NULL
4030 __ if_then(val, BoolTest::ne, null(), unlikely); {
4031
4032 // Ok must mark the card if not already dirty
4033
4034 // load the original value of the card
4035 Node* card_val = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw);
4036
4037 __ if_then(card_val, BoolTest::ne, young_card); {
4038 sync_kit(ideal);
4039 // Use Op_MemBarVolatile to achieve the effect of a StoreLoad barrier.
4040 insert_mem_bar(Op_MemBarVolatile, oop_store);
4041 __ sync_kit(this);
4042
4043 Node* card_val_reload = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw);
4044 __ if_then(card_val_reload, BoolTest::ne, dirty_card); {
4045 g1_mark_card(ideal, card_adr, oop_store, alias_idx, index, index_adr, buffer, tf);
4046 } __ end_if();
4047 } __ end_if();
4048 } __ end_if();
4049 } __ end_if();
4050 } else {
4051 // Object.clone() instrinsic uses this path.
4052 g1_mark_card(ideal, card_adr, oop_store, alias_idx, index, index_adr, buffer, tf);
4053 }
4054
4055 // Final sync IdealKit and GraphKit.
4056 final_sync(ideal);
4057 }
4058 #undef __
4059
4060
4061
4062 Node* GraphKit::load_String_offset(Node* ctrl, Node* str) {
4063 if (java_lang_String::has_offset_field()) {
4064 int offset_offset = java_lang_String::offset_offset_in_bytes();
4065 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4066 false, NULL, 0);
4067 const TypePtr* offset_field_type = string_type->add_offset(offset_offset);
4068 int offset_field_idx = C->get_alias_index(offset_field_type);
4069 return make_load(ctrl,
4070 basic_plus_adr(str, str, offset_offset),
4071 TypeInt::INT, T_INT, offset_field_idx, MemNode::unordered);
4072 } else {
4073 return intcon(0);
4074 }
4075 }
4076
4077 Node* GraphKit::load_String_length(Node* ctrl, Node* str) {
4078 if (java_lang_String::has_count_field()) {
4079 int count_offset = java_lang_String::count_offset_in_bytes();
4080 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4081 false, NULL, 0);
4082 const TypePtr* count_field_type = string_type->add_offset(count_offset);
4083 int count_field_idx = C->get_alias_index(count_field_type);
4084 return make_load(ctrl,
4085 basic_plus_adr(str, str, count_offset),
4086 TypeInt::INT, T_INT, count_field_idx, MemNode::unordered);
4087 } else {
4088 return load_array_length(load_String_value(ctrl, str));
4089 }
4090 }
4091
4092 Node* GraphKit::load_String_value(Node* ctrl, Node* str) {
4093 int value_offset = java_lang_String::value_offset_in_bytes();
4094 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4095 false, NULL, 0);
4096 const TypePtr* value_field_type = string_type->add_offset(value_offset);
4097 const TypeAryPtr* value_type = TypeAryPtr::make(TypePtr::NotNull,
4098 TypeAry::make(TypeInt::CHAR,TypeInt::POS),
4099 ciTypeArrayKlass::make(T_CHAR), true, 0);
4100 int value_field_idx = C->get_alias_index(value_field_type);
4101 Node* load = make_load(ctrl, basic_plus_adr(str, str, value_offset),
4102 value_type, T_OBJECT, value_field_idx, MemNode::unordered);
4103 // String.value field is known to be @Stable.
4104 if (UseImplicitStableValues) {
4105 load = cast_array_to_stable(load, value_type);
4106 }
4107 return load;
4108 }
4109
4110 void GraphKit::store_String_offset(Node* ctrl, Node* str, Node* value) {
4111 int offset_offset = java_lang_String::offset_offset_in_bytes();
4112 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4113 false, NULL, 0);
4114 const TypePtr* offset_field_type = string_type->add_offset(offset_offset);
4115 int offset_field_idx = C->get_alias_index(offset_field_type);
4116 store_to_memory(ctrl, basic_plus_adr(str, offset_offset),
4117 value, T_INT, offset_field_idx, MemNode::unordered);
4118 }
4119
4120 void GraphKit::store_String_value(Node* ctrl, Node* str, Node* value) {
4121 int value_offset = java_lang_String::value_offset_in_bytes();
4122 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4123 false, NULL, 0);
4124 const TypePtr* value_field_type = string_type->add_offset(value_offset);
4125
4126 store_oop_to_object(ctrl, str, basic_plus_adr(str, value_offset), value_field_type,
4127 value, TypeAryPtr::CHARS, T_OBJECT, MemNode::unordered);
4128 }
4129
4130 void GraphKit::store_String_length(Node* ctrl, Node* str, Node* value) {
4131 int count_offset = java_lang_String::count_offset_in_bytes();
4132 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4133 false, NULL, 0);
4134 const TypePtr* count_field_type = string_type->add_offset(count_offset);
4135 int count_field_idx = C->get_alias_index(count_field_type);
4136 store_to_memory(ctrl, basic_plus_adr(str, count_offset),
4137 value, T_INT, count_field_idx, MemNode::unordered);
4138 }
4139
4140 Node* GraphKit::cast_array_to_stable(Node* ary, const TypeAryPtr* ary_type) {
4141 // Reify the property as a CastPP node in Ideal graph to comply with monotonicity
4142 // assumption of CCP analysis.
4143 return _gvn.transform(new(C) CastPPNode(ary, ary_type->cast_to_stable(true)));
4144 }