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 "runtime/deoptimization.hpp"
45 #include "runtime/sharedRuntime.hpp"
46
47 //----------------------------GraphKit-----------------------------------------
48 // Main utility constructor.
49 GraphKit::GraphKit(JVMState* jvms)
50 : Phase(Phase::Parser),
51 _env(C->env()),
52 _gvn(*C->initial_gvn())
53 {
54 _exceptions = jvms->map()->next_exception();
55 if (_exceptions != NULL) jvms->map()->set_next_exception(NULL);
56 set_jvms(jvms);
57 }
58
59 // Private constructor for parser.
60 GraphKit::GraphKit()
61 : Phase(Phase::Parser),
62 _env(C->env()),
63 _gvn(*C->initial_gvn())
64 {
65 _exceptions = NULL;
66 set_map(NULL);
67 debug_only(_sp = -99);
68 debug_only(set_bci(-99));
69 }
70
71
72
73 //---------------------------clean_stack---------------------------------------
74 // Clear away rubbish from the stack area of the JVM state.
75 // This destroys any arguments that may be waiting on the stack.
76 void GraphKit::clean_stack(int from_sp) {
77 SafePointNode* map = this->map();
78 JVMState* jvms = this->jvms();
79 int stk_size = jvms->stk_size();
80 int stkoff = jvms->stkoff();
81 Node* top = this->top();
82 for (int i = from_sp; i < stk_size; i++) {
83 if (map->in(stkoff + i) != top) {
84 map->set_req(stkoff + i, top);
85 }
86 }
87 }
88
89
90 //--------------------------------sync_jvms-----------------------------------
91 // Make sure our current jvms agrees with our parse state.
92 JVMState* GraphKit::sync_jvms() const {
93 JVMState* jvms = this->jvms();
94 jvms->set_bci(bci()); // Record the new bci in the JVMState
95 jvms->set_sp(sp()); // Record the new sp in the JVMState
96 assert(jvms_in_sync(), "jvms is now in sync");
97 return jvms;
98 }
99
100 //--------------------------------sync_jvms_for_reexecute---------------------
101 // Make sure our current jvms agrees with our parse state. This version
102 // uses the reexecute_sp for reexecuting bytecodes.
103 JVMState* GraphKit::sync_jvms_for_reexecute() {
104 JVMState* jvms = this->jvms();
105 jvms->set_bci(bci()); // Record the new bci in the JVMState
106 jvms->set_sp(reexecute_sp()); // Record the new sp in the JVMState
107 return jvms;
108 }
109
110 #ifdef ASSERT
111 bool GraphKit::jvms_in_sync() const {
112 Parse* parse = is_Parse();
113 if (parse == NULL) {
114 if (bci() != jvms()->bci()) return false;
115 if (sp() != (int)jvms()->sp()) return false;
116 return true;
117 }
118 if (jvms()->method() != parse->method()) return false;
119 if (jvms()->bci() != parse->bci()) return false;
120 int jvms_sp = jvms()->sp();
121 if (jvms_sp != parse->sp()) return false;
122 int jvms_depth = jvms()->depth();
123 if (jvms_depth != parse->depth()) return false;
124 return true;
125 }
126
127 // Local helper checks for special internal merge points
128 // used to accumulate and merge exception states.
129 // They are marked by the region's in(0) edge being the map itself.
130 // Such merge points must never "escape" into the parser at large,
131 // until they have been handed to gvn.transform.
132 static bool is_hidden_merge(Node* reg) {
133 if (reg == NULL) return false;
134 if (reg->is_Phi()) {
135 reg = reg->in(0);
136 if (reg == NULL) return false;
137 }
138 return reg->is_Region() && reg->in(0) != NULL && reg->in(0)->is_Root();
139 }
140
141 void GraphKit::verify_map() const {
142 if (map() == NULL) return; // null map is OK
143 assert(map()->req() <= jvms()->endoff(), "no extra garbage on map");
144 assert(!map()->has_exceptions(), "call add_exception_states_from 1st");
145 assert(!is_hidden_merge(control()), "call use_exception_state, not set_map");
146 }
147
148 void GraphKit::verify_exception_state(SafePointNode* ex_map) {
149 assert(ex_map->next_exception() == NULL, "not already part of a chain");
150 assert(has_saved_ex_oop(ex_map), "every exception state has an ex_oop");
151 }
152 #endif
153
154 //---------------------------stop_and_kill_map---------------------------------
155 // Set _map to NULL, signalling a stop to further bytecode execution.
156 // First smash the current map's control to a constant, to mark it dead.
157 void GraphKit::stop_and_kill_map() {
158 SafePointNode* dead_map = stop();
159 if (dead_map != NULL) {
160 dead_map->disconnect_inputs(NULL, C); // Mark the map as killed.
161 assert(dead_map->is_killed(), "must be so marked");
162 }
163 }
164
165
166 //--------------------------------stopped--------------------------------------
167 // Tell if _map is NULL, or control is top.
168 bool GraphKit::stopped() {
169 if (map() == NULL) return true;
170 else if (control() == top()) return true;
171 else return false;
172 }
173
174
175 //-----------------------------has_ex_handler----------------------------------
176 // Tell if this method or any caller method has exception handlers.
177 bool GraphKit::has_ex_handler() {
178 for (JVMState* jvmsp = jvms(); jvmsp != NULL; jvmsp = jvmsp->caller()) {
179 if (jvmsp->has_method() && jvmsp->method()->has_exception_handlers()) {
180 return true;
181 }
182 }
183 return false;
184 }
185
186 //------------------------------save_ex_oop------------------------------------
187 // Save an exception without blowing stack contents or other JVM state.
188 void GraphKit::set_saved_ex_oop(SafePointNode* ex_map, Node* ex_oop) {
189 assert(!has_saved_ex_oop(ex_map), "clear ex-oop before setting again");
190 ex_map->add_req(ex_oop);
191 debug_only(verify_exception_state(ex_map));
192 }
193
194 inline static Node* common_saved_ex_oop(SafePointNode* ex_map, bool clear_it) {
195 assert(GraphKit::has_saved_ex_oop(ex_map), "ex_oop must be there");
196 Node* ex_oop = ex_map->in(ex_map->req()-1);
197 if (clear_it) ex_map->del_req(ex_map->req()-1);
198 return ex_oop;
199 }
200
201 //-----------------------------saved_ex_oop------------------------------------
202 // Recover a saved exception from its map.
203 Node* GraphKit::saved_ex_oop(SafePointNode* ex_map) {
204 return common_saved_ex_oop(ex_map, false);
205 }
206
207 //--------------------------clear_saved_ex_oop---------------------------------
208 // Erase a previously saved exception from its map.
209 Node* GraphKit::clear_saved_ex_oop(SafePointNode* ex_map) {
210 return common_saved_ex_oop(ex_map, true);
211 }
212
213 #ifdef ASSERT
214 //---------------------------has_saved_ex_oop----------------------------------
215 // Erase a previously saved exception from its map.
216 bool GraphKit::has_saved_ex_oop(SafePointNode* ex_map) {
217 return ex_map->req() == ex_map->jvms()->endoff()+1;
218 }
219 #endif
220
221 //-------------------------make_exception_state--------------------------------
222 // Turn the current JVM state into an exception state, appending the ex_oop.
223 SafePointNode* GraphKit::make_exception_state(Node* ex_oop) {
224 sync_jvms();
225 SafePointNode* ex_map = stop(); // do not manipulate this map any more
226 set_saved_ex_oop(ex_map, ex_oop);
227 return ex_map;
228 }
229
230
231 //--------------------------add_exception_state--------------------------------
232 // Add an exception to my list of exceptions.
233 void GraphKit::add_exception_state(SafePointNode* ex_map) {
234 if (ex_map == NULL || ex_map->control() == top()) {
235 return;
236 }
237 #ifdef ASSERT
238 verify_exception_state(ex_map);
239 if (has_exceptions()) {
240 assert(ex_map->jvms()->same_calls_as(_exceptions->jvms()), "all collected exceptions must come from the same place");
241 }
242 #endif
243
244 // If there is already an exception of exactly this type, merge with it.
245 // In particular, null-checks and other low-level exceptions common up here.
246 Node* ex_oop = saved_ex_oop(ex_map);
247 const Type* ex_type = _gvn.type(ex_oop);
248 if (ex_oop == top()) {
249 // No action needed.
250 return;
251 }
252 assert(ex_type->isa_instptr(), "exception must be an instance");
253 for (SafePointNode* e2 = _exceptions; e2 != NULL; e2 = e2->next_exception()) {
254 const Type* ex_type2 = _gvn.type(saved_ex_oop(e2));
255 // We check sp also because call bytecodes can generate exceptions
256 // both before and after arguments are popped!
257 if (ex_type2 == ex_type
258 && e2->_jvms->sp() == ex_map->_jvms->sp()) {
259 combine_exception_states(ex_map, e2);
260 return;
261 }
262 }
263
264 // No pre-existing exception of the same type. Chain it on the list.
265 push_exception_state(ex_map);
266 }
267
268 //-----------------------add_exception_states_from-----------------------------
269 void GraphKit::add_exception_states_from(JVMState* jvms) {
270 SafePointNode* ex_map = jvms->map()->next_exception();
271 if (ex_map != NULL) {
272 jvms->map()->set_next_exception(NULL);
273 for (SafePointNode* next_map; ex_map != NULL; ex_map = next_map) {
274 next_map = ex_map->next_exception();
275 ex_map->set_next_exception(NULL);
276 add_exception_state(ex_map);
277 }
278 }
279 }
280
281 //-----------------------transfer_exceptions_into_jvms-------------------------
282 JVMState* GraphKit::transfer_exceptions_into_jvms() {
283 if (map() == NULL) {
284 // We need a JVMS to carry the exceptions, but the map has gone away.
285 // Create a scratch JVMS, cloned from any of the exception states...
286 if (has_exceptions()) {
287 _map = _exceptions;
288 _map = clone_map();
289 _map->set_next_exception(NULL);
290 clear_saved_ex_oop(_map);
291 debug_only(verify_map());
292 } else {
293 // ...or created from scratch
294 JVMState* jvms = new (C) JVMState(_method, NULL);
295 jvms->set_bci(_bci);
296 jvms->set_sp(_sp);
297 jvms->set_map(new SafePointNode(TypeFunc::Parms, jvms));
298 set_jvms(jvms);
299 for (uint i = 0; i < map()->req(); i++) map()->init_req(i, top());
300 set_all_memory(top());
301 while (map()->req() < jvms->endoff()) map()->add_req(top());
302 }
303 // (This is a kludge, in case you didn't notice.)
304 set_control(top());
305 }
306 JVMState* jvms = sync_jvms();
307 assert(!jvms->map()->has_exceptions(), "no exceptions on this map yet");
308 jvms->map()->set_next_exception(_exceptions);
309 _exceptions = NULL; // done with this set of exceptions
310 return jvms;
311 }
312
313 static inline void add_n_reqs(Node* dstphi, Node* srcphi) {
314 assert(is_hidden_merge(dstphi), "must be a special merge node");
315 assert(is_hidden_merge(srcphi), "must be a special merge node");
316 uint limit = srcphi->req();
317 for (uint i = PhiNode::Input; i < limit; i++) {
318 dstphi->add_req(srcphi->in(i));
319 }
320 }
321 static inline void add_one_req(Node* dstphi, Node* src) {
322 assert(is_hidden_merge(dstphi), "must be a special merge node");
323 assert(!is_hidden_merge(src), "must not be a special merge node");
324 dstphi->add_req(src);
325 }
326
327 //-----------------------combine_exception_states------------------------------
328 // This helper function combines exception states by building phis on a
329 // specially marked state-merging region. These regions and phis are
330 // untransformed, and can build up gradually. The region is marked by
331 // having a control input of its exception map, rather than NULL. Such
332 // regions do not appear except in this function, and in use_exception_state.
333 void GraphKit::combine_exception_states(SafePointNode* ex_map, SafePointNode* phi_map) {
334 if (failing()) return; // dying anyway...
335 JVMState* ex_jvms = ex_map->_jvms;
336 assert(ex_jvms->same_calls_as(phi_map->_jvms), "consistent call chains");
337 assert(ex_jvms->stkoff() == phi_map->_jvms->stkoff(), "matching locals");
338 assert(ex_jvms->sp() == phi_map->_jvms->sp(), "matching stack sizes");
339 assert(ex_jvms->monoff() == phi_map->_jvms->monoff(), "matching JVMS");
340 assert(ex_jvms->scloff() == phi_map->_jvms->scloff(), "matching scalar replaced objects");
341 assert(ex_map->req() == phi_map->req(), "matching maps");
342 uint tos = ex_jvms->stkoff() + ex_jvms->sp();
343 Node* hidden_merge_mark = root();
344 Node* region = phi_map->control();
345 MergeMemNode* phi_mem = phi_map->merged_memory();
346 MergeMemNode* ex_mem = ex_map->merged_memory();
347 if (region->in(0) != hidden_merge_mark) {
348 // The control input is not (yet) a specially-marked region in phi_map.
349 // Make it so, and build some phis.
350 region = new RegionNode(2);
351 _gvn.set_type(region, Type::CONTROL);
352 region->set_req(0, hidden_merge_mark); // marks an internal ex-state
353 region->init_req(1, phi_map->control());
354 phi_map->set_control(region);
355 Node* io_phi = PhiNode::make(region, phi_map->i_o(), Type::ABIO);
356 record_for_igvn(io_phi);
357 _gvn.set_type(io_phi, Type::ABIO);
358 phi_map->set_i_o(io_phi);
359 for (MergeMemStream mms(phi_mem); mms.next_non_empty(); ) {
360 Node* m = mms.memory();
361 Node* m_phi = PhiNode::make(region, m, Type::MEMORY, mms.adr_type(C));
362 record_for_igvn(m_phi);
363 _gvn.set_type(m_phi, Type::MEMORY);
364 mms.set_memory(m_phi);
365 }
366 }
367
368 // Either or both of phi_map and ex_map might already be converted into phis.
369 Node* ex_control = ex_map->control();
370 // if there is special marking on ex_map also, we add multiple edges from src
371 bool add_multiple = (ex_control->in(0) == hidden_merge_mark);
372 // how wide was the destination phi_map, originally?
373 uint orig_width = region->req();
374
375 if (add_multiple) {
376 add_n_reqs(region, ex_control);
377 add_n_reqs(phi_map->i_o(), ex_map->i_o());
378 } else {
379 // ex_map has no merges, so we just add single edges everywhere
380 add_one_req(region, ex_control);
381 add_one_req(phi_map->i_o(), ex_map->i_o());
382 }
383 for (MergeMemStream mms(phi_mem, ex_mem); mms.next_non_empty2(); ) {
384 if (mms.is_empty()) {
385 // get a copy of the base memory, and patch some inputs into it
386 const TypePtr* adr_type = mms.adr_type(C);
387 Node* phi = mms.force_memory()->as_Phi()->slice_memory(adr_type);
388 assert(phi->as_Phi()->region() == mms.base_memory()->in(0), "");
389 mms.set_memory(phi);
390 // Prepare to append interesting stuff onto the newly sliced phi:
391 while (phi->req() > orig_width) phi->del_req(phi->req()-1);
392 }
393 // Append stuff from ex_map:
394 if (add_multiple) {
395 add_n_reqs(mms.memory(), mms.memory2());
396 } else {
397 add_one_req(mms.memory(), mms.memory2());
398 }
399 }
400 uint limit = ex_map->req();
401 for (uint i = TypeFunc::Parms; i < limit; i++) {
402 // Skip everything in the JVMS after tos. (The ex_oop follows.)
403 if (i == tos) i = ex_jvms->monoff();
404 Node* src = ex_map->in(i);
405 Node* dst = phi_map->in(i);
406 if (src != dst) {
407 PhiNode* phi;
408 if (dst->in(0) != region) {
409 dst = phi = PhiNode::make(region, dst, _gvn.type(dst));
410 record_for_igvn(phi);
411 _gvn.set_type(phi, phi->type());
412 phi_map->set_req(i, dst);
413 // Prepare to append interesting stuff onto the new phi:
414 while (dst->req() > orig_width) dst->del_req(dst->req()-1);
415 } else {
416 assert(dst->is_Phi(), "nobody else uses a hidden region");
417 phi = dst->as_Phi();
418 }
419 if (add_multiple && src->in(0) == ex_control) {
420 // Both are phis.
421 add_n_reqs(dst, src);
422 } else {
423 while (dst->req() < region->req()) add_one_req(dst, src);
424 }
425 const Type* srctype = _gvn.type(src);
426 if (phi->type() != srctype) {
427 const Type* dsttype = phi->type()->meet_speculative(srctype);
428 if (phi->type() != dsttype) {
429 phi->set_type(dsttype);
430 _gvn.set_type(phi, dsttype);
431 }
432 }
433 }
434 }
435 }
436
437 //--------------------------use_exception_state--------------------------------
438 Node* GraphKit::use_exception_state(SafePointNode* phi_map) {
439 if (failing()) { stop(); return top(); }
440 Node* region = phi_map->control();
441 Node* hidden_merge_mark = root();
442 assert(phi_map->jvms()->map() == phi_map, "sanity: 1-1 relation");
443 Node* ex_oop = clear_saved_ex_oop(phi_map);
444 if (region->in(0) == hidden_merge_mark) {
445 // Special marking for internal ex-states. Process the phis now.
446 region->set_req(0, region); // now it's an ordinary region
447 set_jvms(phi_map->jvms()); // ...so now we can use it as a map
448 // Note: Setting the jvms also sets the bci and sp.
449 set_control(_gvn.transform(region));
450 uint tos = jvms()->stkoff() + sp();
451 for (uint i = 1; i < tos; i++) {
452 Node* x = phi_map->in(i);
453 if (x->in(0) == region) {
454 assert(x->is_Phi(), "expected a special phi");
455 phi_map->set_req(i, _gvn.transform(x));
456 }
457 }
458 for (MergeMemStream mms(merged_memory()); mms.next_non_empty(); ) {
459 Node* x = mms.memory();
460 if (x->in(0) == region) {
461 assert(x->is_Phi(), "nobody else uses a hidden region");
462 mms.set_memory(_gvn.transform(x));
463 }
464 }
465 if (ex_oop->in(0) == region) {
466 assert(ex_oop->is_Phi(), "expected a special phi");
467 ex_oop = _gvn.transform(ex_oop);
468 }
469 } else {
470 set_jvms(phi_map->jvms());
471 }
472
473 assert(!is_hidden_merge(phi_map->control()), "hidden ex. states cleared");
474 assert(!is_hidden_merge(phi_map->i_o()), "hidden ex. states cleared");
475 return ex_oop;
476 }
477
478 //---------------------------------java_bc-------------------------------------
479 Bytecodes::Code GraphKit::java_bc() const {
480 ciMethod* method = this->method();
481 int bci = this->bci();
482 if (method != NULL && bci != InvocationEntryBci)
483 return method->java_code_at_bci(bci);
484 else
485 return Bytecodes::_illegal;
486 }
487
488 void GraphKit::uncommon_trap_if_should_post_on_exceptions(Deoptimization::DeoptReason reason,
489 bool must_throw) {
490 // if the exception capability is set, then we will generate code
491 // to check the JavaThread.should_post_on_exceptions flag to see
492 // if we actually need to report exception events (for this
493 // thread). If we don't need to report exception events, we will
494 // take the normal fast path provided by add_exception_events. If
495 // exception event reporting is enabled for this thread, we will
496 // take the uncommon_trap in the BuildCutout below.
497
498 // first must access the should_post_on_exceptions_flag in this thread's JavaThread
499 Node* jthread = _gvn.transform(new ThreadLocalNode());
500 Node* adr = basic_plus_adr(top(), jthread, in_bytes(JavaThread::should_post_on_exceptions_flag_offset()));
501 Node* should_post_flag = make_load(control(), adr, TypeInt::INT, T_INT, Compile::AliasIdxRaw, MemNode::unordered);
502
503 // Test the should_post_on_exceptions_flag vs. 0
504 Node* chk = _gvn.transform( new CmpINode(should_post_flag, intcon(0)) );
505 Node* tst = _gvn.transform( new BoolNode(chk, BoolTest::eq) );
506
507 // Branch to slow_path if should_post_on_exceptions_flag was true
508 { BuildCutout unless(this, tst, PROB_MAX);
509 // Do not try anything fancy if we're notifying the VM on every throw.
510 // Cf. case Bytecodes::_athrow in parse2.cpp.
511 uncommon_trap(reason, Deoptimization::Action_none,
512 (ciKlass*)NULL, (char*)NULL, must_throw);
513 }
514
515 }
516
517 //------------------------------builtin_throw----------------------------------
518 void GraphKit::builtin_throw(Deoptimization::DeoptReason reason, Node* arg) {
519 bool must_throw = true;
520
521 if (env()->jvmti_can_post_on_exceptions()) {
522 // check if we must post exception events, take uncommon trap if so
523 uncommon_trap_if_should_post_on_exceptions(reason, must_throw);
524 // here if should_post_on_exceptions is false
525 // continue on with the normal codegen
526 }
527
528 // If this particular condition has not yet happened at this
529 // bytecode, then use the uncommon trap mechanism, and allow for
530 // a future recompilation if several traps occur here.
531 // If the throw is hot, try to use a more complicated inline mechanism
532 // which keeps execution inside the compiled code.
533 bool treat_throw_as_hot = false;
534 ciMethodData* md = method()->method_data();
535
536 if (ProfileTraps) {
537 if (too_many_traps(reason)) {
538 treat_throw_as_hot = true;
539 }
540 // (If there is no MDO at all, assume it is early in
541 // execution, and that any deopts are part of the
542 // startup transient, and don't need to be remembered.)
543
544 // Also, if there is a local exception handler, treat all throws
545 // as hot if there has been at least one in this method.
546 if (C->trap_count(reason) != 0
547 && method()->method_data()->trap_count(reason) != 0
548 && has_ex_handler()) {
549 treat_throw_as_hot = true;
550 }
551 }
552
553 // If this throw happens frequently, an uncommon trap might cause
554 // a performance pothole. If there is a local exception handler,
555 // and if this particular bytecode appears to be deoptimizing often,
556 // let us handle the throw inline, with a preconstructed instance.
557 // Note: If the deopt count has blown up, the uncommon trap
558 // runtime is going to flush this nmethod, not matter what.
559 if (treat_throw_as_hot
560 && (!StackTraceInThrowable || OmitStackTraceInFastThrow)) {
561 // If the throw is local, we use a pre-existing instance and
562 // punt on the backtrace. This would lead to a missing backtrace
563 // (a repeat of 4292742) if the backtrace object is ever asked
564 // for its backtrace.
565 // Fixing this remaining case of 4292742 requires some flavor of
566 // escape analysis. Leave that for the future.
567 ciInstance* ex_obj = NULL;
568 switch (reason) {
569 case Deoptimization::Reason_null_check:
570 ex_obj = env()->NullPointerException_instance();
571 break;
572 case Deoptimization::Reason_div0_check:
573 ex_obj = env()->ArithmeticException_instance();
574 break;
575 case Deoptimization::Reason_range_check:
576 ex_obj = env()->ArrayIndexOutOfBoundsException_instance();
577 break;
578 case Deoptimization::Reason_class_check:
579 if (java_bc() == Bytecodes::_aastore) {
580 ex_obj = env()->ArrayStoreException_instance();
581 } else {
582 ex_obj = env()->ClassCastException_instance();
583 }
584 break;
585 }
586 if (failing()) { stop(); return; } // exception allocation might fail
587 if (ex_obj != NULL) {
588 // Cheat with a preallocated exception object.
589 if (C->log() != NULL)
590 C->log()->elem("hot_throw preallocated='1' reason='%s'",
591 Deoptimization::trap_reason_name(reason));
592 const TypeInstPtr* ex_con = TypeInstPtr::make(ex_obj);
593 Node* ex_node = _gvn.transform( ConNode::make(C, ex_con) );
594
595 // Clear the detail message of the preallocated exception object.
596 // Weblogic sometimes mutates the detail message of exceptions
597 // using reflection.
598 int offset = java_lang_Throwable::get_detailMessage_offset();
599 const TypePtr* adr_typ = ex_con->add_offset(offset);
600
601 Node *adr = basic_plus_adr(ex_node, ex_node, offset);
602 const TypeOopPtr* val_type = TypeOopPtr::make_from_klass(env()->String_klass());
603 // Conservatively release stores of object references.
604 Node *store = store_oop_to_object(control(), ex_node, adr, adr_typ, null(), val_type, T_OBJECT, MemNode::release);
605
606 add_exception_state(make_exception_state(ex_node));
607 return;
608 }
609 }
610
611 // %%% Maybe add entry to OptoRuntime which directly throws the exc.?
612 // It won't be much cheaper than bailing to the interp., since we'll
613 // have to pass up all the debug-info, and the runtime will have to
614 // create the stack trace.
615
616 // Usual case: Bail to interpreter.
617 // Reserve the right to recompile if we haven't seen anything yet.
618
619 ciMethod* m = Deoptimization::reason_is_speculate(reason) ? C->method() : NULL;
620 Deoptimization::DeoptAction action = Deoptimization::Action_maybe_recompile;
621 if (treat_throw_as_hot
622 && (method()->method_data()->trap_recompiled_at(bci(), m)
623 || C->too_many_traps(reason))) {
624 // We cannot afford to take more traps here. Suffer in the interpreter.
625 if (C->log() != NULL)
626 C->log()->elem("hot_throw preallocated='0' reason='%s' mcount='%d'",
627 Deoptimization::trap_reason_name(reason),
628 C->trap_count(reason));
629 action = Deoptimization::Action_none;
630 }
631
632 // "must_throw" prunes the JVM state to include only the stack, if there
633 // are no local exception handlers. This should cut down on register
634 // allocation time and code size, by drastically reducing the number
635 // of in-edges on the call to the uncommon trap.
636
637 uncommon_trap(reason, action, (ciKlass*)NULL, (char*)NULL, must_throw);
638 }
639
640
641 //----------------------------PreserveJVMState---------------------------------
642 PreserveJVMState::PreserveJVMState(GraphKit* kit, bool clone_map) {
643 debug_only(kit->verify_map());
644 _kit = kit;
645 _map = kit->map(); // preserve the map
646 _sp = kit->sp();
647 kit->set_map(clone_map ? kit->clone_map() : NULL);
648 Compile::current()->inc_preserve_jvm_state();
649 #ifdef ASSERT
650 _bci = kit->bci();
651 Parse* parser = kit->is_Parse();
652 int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo();
653 _block = block;
654 #endif
655 }
656 PreserveJVMState::~PreserveJVMState() {
657 GraphKit* kit = _kit;
658 #ifdef ASSERT
659 assert(kit->bci() == _bci, "bci must not shift");
660 Parse* parser = kit->is_Parse();
661 int block = (parser == NULL || parser->block() == NULL) ? -1 : parser->block()->rpo();
662 assert(block == _block, "block must not shift");
663 #endif
664 kit->set_map(_map);
665 kit->set_sp(_sp);
666 Compile::current()->dec_preserve_jvm_state();
667 }
668
669
670 //-----------------------------BuildCutout-------------------------------------
671 BuildCutout::BuildCutout(GraphKit* kit, Node* p, float prob, float cnt)
672 : PreserveJVMState(kit)
673 {
674 assert(p->is_Con() || p->is_Bool(), "test must be a bool");
675 SafePointNode* outer_map = _map; // preserved map is caller's
676 SafePointNode* inner_map = kit->map();
677 IfNode* iff = kit->create_and_map_if(outer_map->control(), p, prob, cnt);
678 outer_map->set_control(kit->gvn().transform( new IfTrueNode(iff) ));
679 inner_map->set_control(kit->gvn().transform( new IfFalseNode(iff) ));
680 }
681 BuildCutout::~BuildCutout() {
682 GraphKit* kit = _kit;
683 assert(kit->stopped(), "cutout code must stop, throw, return, etc.");
684 }
685
686 //---------------------------PreserveReexecuteState----------------------------
687 PreserveReexecuteState::PreserveReexecuteState(GraphKit* kit) {
688 assert(!kit->stopped(), "must call stopped() before");
689 _kit = kit;
690 _sp = kit->sp();
691 _reexecute = kit->jvms()->_reexecute;
692 }
693 PreserveReexecuteState::~PreserveReexecuteState() {
694 if (_kit->stopped()) return;
695 _kit->jvms()->_reexecute = _reexecute;
696 _kit->set_sp(_sp);
697 }
698
699 //------------------------------clone_map--------------------------------------
700 // Implementation of PreserveJVMState
701 //
702 // Only clone_map(...) here. If this function is only used in the
703 // PreserveJVMState class we may want to get rid of this extra
704 // function eventually and do it all there.
705
706 SafePointNode* GraphKit::clone_map() {
707 if (map() == NULL) return NULL;
708
709 // Clone the memory edge first
710 Node* mem = MergeMemNode::make(C, map()->memory());
711 gvn().set_type_bottom(mem);
712
713 SafePointNode *clonemap = (SafePointNode*)map()->clone();
714 JVMState* jvms = this->jvms();
715 JVMState* clonejvms = jvms->clone_shallow(C);
716 clonemap->set_memory(mem);
717 clonemap->set_jvms(clonejvms);
718 clonejvms->set_map(clonemap);
719 record_for_igvn(clonemap);
720 gvn().set_type_bottom(clonemap);
721 return clonemap;
722 }
723
724
725 //-----------------------------set_map_clone-----------------------------------
726 void GraphKit::set_map_clone(SafePointNode* m) {
727 _map = m;
728 _map = clone_map();
729 _map->set_next_exception(NULL);
730 debug_only(verify_map());
731 }
732
733
734 //----------------------------kill_dead_locals---------------------------------
735 // Detect any locals which are known to be dead, and force them to top.
736 void GraphKit::kill_dead_locals() {
737 // Consult the liveness information for the locals. If any
738 // of them are unused, then they can be replaced by top(). This
739 // should help register allocation time and cut down on the size
740 // of the deoptimization information.
741
742 // This call is made from many of the bytecode handling
743 // subroutines called from the Big Switch in do_one_bytecode.
744 // Every bytecode which might include a slow path is responsible
745 // for killing its dead locals. The more consistent we
746 // are about killing deads, the fewer useless phis will be
747 // constructed for them at various merge points.
748
749 // bci can be -1 (InvocationEntryBci). We return the entry
750 // liveness for the method.
751
752 if (method() == NULL || method()->code_size() == 0) {
753 // We are building a graph for a call to a native method.
754 // All locals are live.
755 return;
756 }
757
758 ResourceMark rm;
759
760 // Consult the liveness information for the locals. If any
761 // of them are unused, then they can be replaced by top(). This
762 // should help register allocation time and cut down on the size
763 // of the deoptimization information.
764 MethodLivenessResult live_locals = method()->liveness_at_bci(bci());
765
766 int len = (int)live_locals.size();
767 assert(len <= jvms()->loc_size(), "too many live locals");
768 for (int local = 0; local < len; local++) {
769 if (!live_locals.at(local)) {
770 set_local(local, top());
771 }
772 }
773 }
774
775 #ifdef ASSERT
776 //-------------------------dead_locals_are_killed------------------------------
777 // Return true if all dead locals are set to top in the map.
778 // Used to assert "clean" debug info at various points.
779 bool GraphKit::dead_locals_are_killed() {
780 if (method() == NULL || method()->code_size() == 0) {
781 // No locals need to be dead, so all is as it should be.
782 return true;
783 }
784
785 // Make sure somebody called kill_dead_locals upstream.
786 ResourceMark rm;
787 for (JVMState* jvms = this->jvms(); jvms != NULL; jvms = jvms->caller()) {
788 if (jvms->loc_size() == 0) continue; // no locals to consult
789 SafePointNode* map = jvms->map();
790 ciMethod* method = jvms->method();
791 int bci = jvms->bci();
792 if (jvms == this->jvms()) {
793 bci = this->bci(); // it might not yet be synched
794 }
795 MethodLivenessResult live_locals = method->liveness_at_bci(bci);
796 int len = (int)live_locals.size();
797 if (!live_locals.is_valid() || len == 0)
798 // This method is trivial, or is poisoned by a breakpoint.
799 return true;
800 assert(len == jvms->loc_size(), "live map consistent with locals map");
801 for (int local = 0; local < len; local++) {
802 if (!live_locals.at(local) && map->local(jvms, local) != top()) {
803 if (PrintMiscellaneous && (Verbose || WizardMode)) {
804 tty->print_cr("Zombie local %d: ", local);
805 jvms->dump();
806 }
807 return false;
808 }
809 }
810 }
811 return true;
812 }
813
814 #endif //ASSERT
815
816 // Helper function for enforcing certain bytecodes to reexecute if
817 // deoptimization happens
818 static bool should_reexecute_implied_by_bytecode(JVMState *jvms, bool is_anewarray) {
819 ciMethod* cur_method = jvms->method();
820 int cur_bci = jvms->bci();
821 if (cur_method != NULL && cur_bci != InvocationEntryBci) {
822 Bytecodes::Code code = cur_method->java_code_at_bci(cur_bci);
823 return Interpreter::bytecode_should_reexecute(code) ||
824 is_anewarray && code == Bytecodes::_multianewarray;
825 // Reexecute _multianewarray bytecode which was replaced with
826 // sequence of [a]newarray. See Parse::do_multianewarray().
827 //
828 // Note: interpreter should not have it set since this optimization
829 // is limited by dimensions and guarded by flag so in some cases
830 // multianewarray() runtime calls will be generated and
831 // the bytecode should not be reexecutes (stack will not be reset).
832 } else
833 return false;
834 }
835
836 // Helper function for adding JVMState and debug information to node
837 void GraphKit::add_safepoint_edges(SafePointNode* call, bool must_throw) {
838 // Add the safepoint edges to the call (or other safepoint).
839
840 // Make sure dead locals are set to top. This
841 // should help register allocation time and cut down on the size
842 // of the deoptimization information.
843 assert(dead_locals_are_killed(), "garbage in debug info before safepoint");
844
845 // Walk the inline list to fill in the correct set of JVMState's
846 // Also fill in the associated edges for each JVMState.
847
848 // If the bytecode needs to be reexecuted we need to put
849 // the arguments back on the stack.
850 const bool should_reexecute = jvms()->should_reexecute();
851 JVMState* youngest_jvms = should_reexecute ? sync_jvms_for_reexecute() : sync_jvms();
852
853 // NOTE: set_bci (called from sync_jvms) might reset the reexecute bit to
854 // undefined if the bci is different. This is normal for Parse but it
855 // should not happen for LibraryCallKit because only one bci is processed.
856 assert(!is_LibraryCallKit() || (jvms()->should_reexecute() == should_reexecute),
857 "in LibraryCallKit the reexecute bit should not change");
858
859 // If we are guaranteed to throw, we can prune everything but the
860 // input to the current bytecode.
861 bool can_prune_locals = false;
862 uint stack_slots_not_pruned = 0;
863 int inputs = 0, depth = 0;
864 if (must_throw) {
865 assert(method() == youngest_jvms->method(), "sanity");
866 if (compute_stack_effects(inputs, depth)) {
867 can_prune_locals = true;
868 stack_slots_not_pruned = inputs;
869 }
870 }
871
872 if (env()->should_retain_local_variables()) {
873 // At any safepoint, this method can get breakpointed, which would
874 // then require an immediate deoptimization.
875 can_prune_locals = false; // do not prune locals
876 stack_slots_not_pruned = 0;
877 }
878
879 // do not scribble on the input jvms
880 JVMState* out_jvms = youngest_jvms->clone_deep(C);
881 call->set_jvms(out_jvms); // Start jvms list for call node
882
883 // For a known set of bytecodes, the interpreter should reexecute them if
884 // deoptimization happens. We set the reexecute state for them here
885 if (out_jvms->is_reexecute_undefined() && //don't change if already specified
886 should_reexecute_implied_by_bytecode(out_jvms, call->is_AllocateArray())) {
887 out_jvms->set_should_reexecute(true); //NOTE: youngest_jvms not changed
888 }
889
890 // Presize the call:
891 DEBUG_ONLY(uint non_debug_edges = call->req());
892 call->add_req_batch(top(), youngest_jvms->debug_depth());
893 assert(call->req() == non_debug_edges + youngest_jvms->debug_depth(), "");
894
895 // Set up edges so that the call looks like this:
896 // Call [state:] ctl io mem fptr retadr
897 // [parms:] parm0 ... parmN
898 // [root:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
899 // [...mid:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN [...]
900 // [young:] loc0 ... locN stk0 ... stkSP mon0 obj0 ... monN objN
901 // Note that caller debug info precedes callee debug info.
902
903 // Fill pointer walks backwards from "young:" to "root:" in the diagram above:
904 uint debug_ptr = call->req();
905
906 // Loop over the map input edges associated with jvms, add them
907 // to the call node, & reset all offsets to match call node array.
908 for (JVMState* in_jvms = youngest_jvms; in_jvms != NULL; ) {
909 uint debug_end = debug_ptr;
910 uint debug_start = debug_ptr - in_jvms->debug_size();
911 debug_ptr = debug_start; // back up the ptr
912
913 uint p = debug_start; // walks forward in [debug_start, debug_end)
914 uint j, k, l;
915 SafePointNode* in_map = in_jvms->map();
916 out_jvms->set_map(call);
917
918 if (can_prune_locals) {
919 assert(in_jvms->method() == out_jvms->method(), "sanity");
920 // If the current throw can reach an exception handler in this JVMS,
921 // then we must keep everything live that can reach that handler.
922 // As a quick and dirty approximation, we look for any handlers at all.
923 if (in_jvms->method()->has_exception_handlers()) {
924 can_prune_locals = false;
925 }
926 }
927
928 // Add the Locals
929 k = in_jvms->locoff();
930 l = in_jvms->loc_size();
931 out_jvms->set_locoff(p);
932 if (!can_prune_locals) {
933 for (j = 0; j < l; j++)
934 call->set_req(p++, in_map->in(k+j));
935 } else {
936 p += l; // already set to top above by add_req_batch
937 }
938
939 // Add the Expression Stack
940 k = in_jvms->stkoff();
941 l = in_jvms->sp();
942 out_jvms->set_stkoff(p);
943 if (!can_prune_locals) {
944 for (j = 0; j < l; j++)
945 call->set_req(p++, in_map->in(k+j));
946 } else if (can_prune_locals && stack_slots_not_pruned != 0) {
947 // Divide stack into {S0,...,S1}, where S0 is set to top.
948 uint s1 = stack_slots_not_pruned;
949 stack_slots_not_pruned = 0; // for next iteration
950 if (s1 > l) s1 = l;
951 uint s0 = l - s1;
952 p += s0; // skip the tops preinstalled by add_req_batch
953 for (j = s0; j < l; j++)
954 call->set_req(p++, in_map->in(k+j));
955 } else {
956 p += l; // already set to top above by add_req_batch
957 }
958
959 // Add the Monitors
960 k = in_jvms->monoff();
961 l = in_jvms->mon_size();
962 out_jvms->set_monoff(p);
963 for (j = 0; j < l; j++)
964 call->set_req(p++, in_map->in(k+j));
965
966 // Copy any scalar object fields.
967 k = in_jvms->scloff();
968 l = in_jvms->scl_size();
969 out_jvms->set_scloff(p);
970 for (j = 0; j < l; j++)
971 call->set_req(p++, in_map->in(k+j));
972
973 // Finish the new jvms.
974 out_jvms->set_endoff(p);
975
976 assert(out_jvms->endoff() == debug_end, "fill ptr must match");
977 assert(out_jvms->depth() == in_jvms->depth(), "depth must match");
978 assert(out_jvms->loc_size() == in_jvms->loc_size(), "size must match");
979 assert(out_jvms->mon_size() == in_jvms->mon_size(), "size must match");
980 assert(out_jvms->scl_size() == in_jvms->scl_size(), "size must match");
981 assert(out_jvms->debug_size() == in_jvms->debug_size(), "size must match");
982
983 // Update the two tail pointers in parallel.
984 out_jvms = out_jvms->caller();
985 in_jvms = in_jvms->caller();
986 }
987
988 assert(debug_ptr == non_debug_edges, "debug info must fit exactly");
989
990 // Test the correctness of JVMState::debug_xxx accessors:
991 assert(call->jvms()->debug_start() == non_debug_edges, "");
992 assert(call->jvms()->debug_end() == call->req(), "");
993 assert(call->jvms()->debug_depth() == call->req() - non_debug_edges, "");
994 }
995
996 bool GraphKit::compute_stack_effects(int& inputs, int& depth) {
997 Bytecodes::Code code = java_bc();
998 if (code == Bytecodes::_wide) {
999 code = method()->java_code_at_bci(bci() + 1);
1000 }
1001
1002 BasicType rtype = T_ILLEGAL;
1003 int rsize = 0;
1004
1005 if (code != Bytecodes::_illegal) {
1006 depth = Bytecodes::depth(code); // checkcast=0, athrow=-1
1007 rtype = Bytecodes::result_type(code); // checkcast=P, athrow=V
1008 if (rtype < T_CONFLICT)
1009 rsize = type2size[rtype];
1010 }
1011
1012 switch (code) {
1013 case Bytecodes::_illegal:
1014 return false;
1015
1016 case Bytecodes::_ldc:
1017 case Bytecodes::_ldc_w:
1018 case Bytecodes::_ldc2_w:
1019 inputs = 0;
1020 break;
1021
1022 case Bytecodes::_dup: inputs = 1; break;
1023 case Bytecodes::_dup_x1: inputs = 2; break;
1024 case Bytecodes::_dup_x2: inputs = 3; break;
1025 case Bytecodes::_dup2: inputs = 2; break;
1026 case Bytecodes::_dup2_x1: inputs = 3; break;
1027 case Bytecodes::_dup2_x2: inputs = 4; break;
1028 case Bytecodes::_swap: inputs = 2; break;
1029 case Bytecodes::_arraylength: inputs = 1; break;
1030
1031 case Bytecodes::_getstatic:
1032 case Bytecodes::_putstatic:
1033 case Bytecodes::_getfield:
1034 case Bytecodes::_putfield:
1035 {
1036 bool ignored_will_link;
1037 ciField* field = method()->get_field_at_bci(bci(), ignored_will_link);
1038 int size = field->type()->size();
1039 bool is_get = (depth >= 0), is_static = (depth & 1);
1040 inputs = (is_static ? 0 : 1);
1041 if (is_get) {
1042 depth = size - inputs;
1043 } else {
1044 inputs += size; // putxxx pops the value from the stack
1045 depth = - inputs;
1046 }
1047 }
1048 break;
1049
1050 case Bytecodes::_invokevirtual:
1051 case Bytecodes::_invokespecial:
1052 case Bytecodes::_invokestatic:
1053 case Bytecodes::_invokedynamic:
1054 case Bytecodes::_invokeinterface:
1055 {
1056 bool ignored_will_link;
1057 ciSignature* declared_signature = NULL;
1058 ciMethod* ignored_callee = method()->get_method_at_bci(bci(), ignored_will_link, &declared_signature);
1059 assert(declared_signature != NULL, "cannot be null");
1060 inputs = declared_signature->arg_size_for_bc(code);
1061 int size = declared_signature->return_type()->size();
1062 depth = size - inputs;
1063 }
1064 break;
1065
1066 case Bytecodes::_multianewarray:
1067 {
1068 ciBytecodeStream iter(method());
1069 iter.reset_to_bci(bci());
1070 iter.next();
1071 inputs = iter.get_dimensions();
1072 assert(rsize == 1, "");
1073 depth = rsize - inputs;
1074 }
1075 break;
1076
1077 case Bytecodes::_ireturn:
1078 case Bytecodes::_lreturn:
1079 case Bytecodes::_freturn:
1080 case Bytecodes::_dreturn:
1081 case Bytecodes::_areturn:
1082 assert(rsize = -depth, "");
1083 inputs = rsize;
1084 break;
1085
1086 case Bytecodes::_jsr:
1087 case Bytecodes::_jsr_w:
1088 inputs = 0;
1089 depth = 1; // S.B. depth=1, not zero
1090 break;
1091
1092 default:
1093 // bytecode produces a typed result
1094 inputs = rsize - depth;
1095 assert(inputs >= 0, "");
1096 break;
1097 }
1098
1099 #ifdef ASSERT
1100 // spot check
1101 int outputs = depth + inputs;
1102 assert(outputs >= 0, "sanity");
1103 switch (code) {
1104 case Bytecodes::_checkcast: assert(inputs == 1 && outputs == 1, ""); break;
1105 case Bytecodes::_athrow: assert(inputs == 1 && outputs == 0, ""); break;
1106 case Bytecodes::_aload_0: assert(inputs == 0 && outputs == 1, ""); break;
1107 case Bytecodes::_return: assert(inputs == 0 && outputs == 0, ""); break;
1108 case Bytecodes::_drem: assert(inputs == 4 && outputs == 2, ""); break;
1109 }
1110 #endif //ASSERT
1111
1112 return true;
1113 }
1114
1115
1116
1117 //------------------------------basic_plus_adr---------------------------------
1118 Node* GraphKit::basic_plus_adr(Node* base, Node* ptr, Node* offset) {
1119 // short-circuit a common case
1120 if (offset == intcon(0)) return ptr;
1121 return _gvn.transform( new AddPNode(base, ptr, offset) );
1122 }
1123
1124 Node* GraphKit::ConvI2L(Node* offset) {
1125 // short-circuit a common case
1126 jint offset_con = find_int_con(offset, Type::OffsetBot);
1127 if (offset_con != Type::OffsetBot) {
1128 return longcon((jlong) offset_con);
1129 }
1130 return _gvn.transform( new ConvI2LNode(offset));
1131 }
1132
1133 Node* GraphKit::ConvI2UL(Node* offset) {
1134 juint offset_con = (juint) find_int_con(offset, Type::OffsetBot);
1135 if (offset_con != (juint) Type::OffsetBot) {
1136 return longcon((julong) offset_con);
1137 }
1138 Node* conv = _gvn.transform( new ConvI2LNode(offset));
1139 Node* mask = _gvn.transform( ConLNode::make(C, (julong) max_juint) );
1140 return _gvn.transform( new AndLNode(conv, mask) );
1141 }
1142
1143 Node* GraphKit::ConvL2I(Node* offset) {
1144 // short-circuit a common case
1145 jlong offset_con = find_long_con(offset, (jlong)Type::OffsetBot);
1146 if (offset_con != (jlong)Type::OffsetBot) {
1147 return intcon((int) offset_con);
1148 }
1149 return _gvn.transform( new ConvL2INode(offset));
1150 }
1151
1152 //-------------------------load_object_klass-----------------------------------
1153 Node* GraphKit::load_object_klass(Node* obj) {
1154 // Special-case a fresh allocation to avoid building nodes:
1155 Node* akls = AllocateNode::Ideal_klass(obj, &_gvn);
1156 if (akls != NULL) return akls;
1157 Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes());
1158 return _gvn.transform( LoadKlassNode::make(_gvn, immutable_memory(), k_adr, TypeInstPtr::KLASS) );
1159 }
1160
1161 //-------------------------load_array_length-----------------------------------
1162 Node* GraphKit::load_array_length(Node* array) {
1163 // Special-case a fresh allocation to avoid building nodes:
1164 AllocateArrayNode* alloc = AllocateArrayNode::Ideal_array_allocation(array, &_gvn);
1165 Node *alen;
1166 if (alloc == NULL) {
1167 Node *r_adr = basic_plus_adr(array, arrayOopDesc::length_offset_in_bytes());
1168 alen = _gvn.transform( new LoadRangeNode(0, immutable_memory(), r_adr, TypeInt::POS));
1169 } else {
1170 alen = alloc->Ideal_length();
1171 Node* ccast = alloc->make_ideal_length(_gvn.type(array)->is_oopptr(), &_gvn);
1172 if (ccast != alen) {
1173 alen = _gvn.transform(ccast);
1174 }
1175 }
1176 return alen;
1177 }
1178
1179 //------------------------------do_null_check----------------------------------
1180 // Helper function to do a NULL pointer check. Returned value is
1181 // the incoming address with NULL casted away. You are allowed to use the
1182 // not-null value only if you are control dependent on the test.
1183 extern int explicit_null_checks_inserted,
1184 explicit_null_checks_elided;
1185 Node* GraphKit::null_check_common(Node* value, BasicType type,
1186 // optional arguments for variations:
1187 bool assert_null,
1188 Node* *null_control,
1189 bool speculative) {
1190 assert(!assert_null || null_control == NULL, "not both at once");
1191 if (stopped()) return top();
1192 if (!GenerateCompilerNullChecks && !assert_null && null_control == NULL) {
1193 // For some performance testing, we may wish to suppress null checking.
1194 value = cast_not_null(value); // Make it appear to be non-null (4962416).
1195 return value;
1196 }
1197 explicit_null_checks_inserted++;
1198
1199 // Construct NULL check
1200 Node *chk = NULL;
1201 switch(type) {
1202 case T_LONG : chk = new CmpLNode(value, _gvn.zerocon(T_LONG)); break;
1203 case T_INT : chk = new CmpINode(value, _gvn.intcon(0)); break;
1204 case T_ARRAY : // fall through
1205 type = T_OBJECT; // simplify further tests
1206 case T_OBJECT : {
1207 const Type *t = _gvn.type( value );
1208
1209 const TypeOopPtr* tp = t->isa_oopptr();
1210 if (tp != NULL && tp->klass() != NULL && !tp->klass()->is_loaded()
1211 // Only for do_null_check, not any of its siblings:
1212 && !assert_null && null_control == NULL) {
1213 // Usually, any field access or invocation on an unloaded oop type
1214 // will simply fail to link, since the statically linked class is
1215 // likely also to be unloaded. However, in -Xcomp mode, sometimes
1216 // the static class is loaded but the sharper oop type is not.
1217 // Rather than checking for this obscure case in lots of places,
1218 // we simply observe that a null check on an unloaded class
1219 // will always be followed by a nonsense operation, so we
1220 // can just issue the uncommon trap here.
1221 // Our access to the unloaded class will only be correct
1222 // after it has been loaded and initialized, which requires
1223 // a trip through the interpreter.
1224 #ifndef PRODUCT
1225 if (WizardMode) { tty->print("Null check of unloaded "); tp->klass()->print(); tty->cr(); }
1226 #endif
1227 uncommon_trap(Deoptimization::Reason_unloaded,
1228 Deoptimization::Action_reinterpret,
1229 tp->klass(), "!loaded");
1230 return top();
1231 }
1232
1233 if (assert_null) {
1234 // See if the type is contained in NULL_PTR.
1235 // If so, then the value is already null.
1236 if (t->higher_equal(TypePtr::NULL_PTR)) {
1237 explicit_null_checks_elided++;
1238 return value; // Elided null assert quickly!
1239 }
1240 } else {
1241 // See if mixing in the NULL pointer changes type.
1242 // If so, then the NULL pointer was not allowed in the original
1243 // type. In other words, "value" was not-null.
1244 if (t->meet(TypePtr::NULL_PTR) != t->remove_speculative()) {
1245 // same as: if (!TypePtr::NULL_PTR->higher_equal(t)) ...
1246 explicit_null_checks_elided++;
1247 return value; // Elided null check quickly!
1248 }
1249 }
1250 chk = new CmpPNode( value, null() );
1251 break;
1252 }
1253
1254 default:
1255 fatal(err_msg_res("unexpected type: %s", type2name(type)));
1256 }
1257 assert(chk != NULL, "sanity check");
1258 chk = _gvn.transform(chk);
1259
1260 BoolTest::mask btest = assert_null ? BoolTest::eq : BoolTest::ne;
1261 BoolNode *btst = new BoolNode( chk, btest);
1262 Node *tst = _gvn.transform( btst );
1263
1264 //-----------
1265 // if peephole optimizations occurred, a prior test existed.
1266 // If a prior test existed, maybe it dominates as we can avoid this test.
1267 if (tst != btst && type == T_OBJECT) {
1268 // At this point we want to scan up the CFG to see if we can
1269 // find an identical test (and so avoid this test altogether).
1270 Node *cfg = control();
1271 int depth = 0;
1272 while( depth < 16 ) { // Limit search depth for speed
1273 if( cfg->Opcode() == Op_IfTrue &&
1274 cfg->in(0)->in(1) == tst ) {
1275 // Found prior test. Use "cast_not_null" to construct an identical
1276 // CastPP (and hence hash to) as already exists for the prior test.
1277 // Return that casted value.
1278 if (assert_null) {
1279 replace_in_map(value, null());
1280 return null(); // do not issue the redundant test
1281 }
1282 Node *oldcontrol = control();
1283 set_control(cfg);
1284 Node *res = cast_not_null(value);
1285 set_control(oldcontrol);
1286 explicit_null_checks_elided++;
1287 return res;
1288 }
1289 cfg = IfNode::up_one_dom(cfg, /*linear_only=*/ true);
1290 if (cfg == NULL) break; // Quit at region nodes
1291 depth++;
1292 }
1293 }
1294
1295 //-----------
1296 // Branch to failure if null
1297 float ok_prob = PROB_MAX; // a priori estimate: nulls never happen
1298 Deoptimization::DeoptReason reason;
1299 if (assert_null) {
1300 reason = Deoptimization::Reason_null_assert;
1301 } else if (type == T_OBJECT) {
1302 reason = Deoptimization::reason_null_check(speculative);
1303 } else {
1304 reason = Deoptimization::Reason_div0_check;
1305 }
1306 // %%% Since Reason_unhandled is not recorded on a per-bytecode basis,
1307 // ciMethodData::has_trap_at will return a conservative -1 if any
1308 // must-be-null assertion has failed. This could cause performance
1309 // problems for a method after its first do_null_assert failure.
1310 // Consider using 'Reason_class_check' instead?
1311
1312 // To cause an implicit null check, we set the not-null probability
1313 // to the maximum (PROB_MAX). For an explicit check the probability
1314 // is set to a smaller value.
1315 if (null_control != NULL || too_many_traps(reason)) {
1316 // probability is less likely
1317 ok_prob = PROB_LIKELY_MAG(3);
1318 } else if (!assert_null &&
1319 (ImplicitNullCheckThreshold > 0) &&
1320 method() != NULL &&
1321 (method()->method_data()->trap_count(reason)
1322 >= (uint)ImplicitNullCheckThreshold)) {
1323 ok_prob = PROB_LIKELY_MAG(3);
1324 }
1325
1326 if (null_control != NULL) {
1327 IfNode* iff = create_and_map_if(control(), tst, ok_prob, COUNT_UNKNOWN);
1328 Node* null_true = _gvn.transform( new IfFalseNode(iff));
1329 set_control( _gvn.transform( new IfTrueNode(iff)));
1330 if (null_true == top())
1331 explicit_null_checks_elided++;
1332 (*null_control) = null_true;
1333 } else {
1334 BuildCutout unless(this, tst, ok_prob);
1335 // Check for optimizer eliding test at parse time
1336 if (stopped()) {
1337 // Failure not possible; do not bother making uncommon trap.
1338 explicit_null_checks_elided++;
1339 } else if (assert_null) {
1340 uncommon_trap(reason,
1341 Deoptimization::Action_make_not_entrant,
1342 NULL, "assert_null");
1343 } else {
1344 replace_in_map(value, zerocon(type));
1345 builtin_throw(reason);
1346 }
1347 }
1348
1349 // Must throw exception, fall-thru not possible?
1350 if (stopped()) {
1351 return top(); // No result
1352 }
1353
1354 if (assert_null) {
1355 // Cast obj to null on this path.
1356 replace_in_map(value, zerocon(type));
1357 return zerocon(type);
1358 }
1359
1360 // Cast obj to not-null on this path, if there is no null_control.
1361 // (If there is a null_control, a non-null value may come back to haunt us.)
1362 if (type == T_OBJECT) {
1363 Node* cast = cast_not_null(value, false);
1364 if (null_control == NULL || (*null_control) == top())
1365 replace_in_map(value, cast);
1366 value = cast;
1367 }
1368
1369 return value;
1370 }
1371
1372
1373 //------------------------------cast_not_null----------------------------------
1374 // Cast obj to not-null on this path
1375 Node* GraphKit::cast_not_null(Node* obj, bool do_replace_in_map) {
1376 const Type *t = _gvn.type(obj);
1377 const Type *t_not_null = t->join_speculative(TypePtr::NOTNULL);
1378 // Object is already not-null?
1379 if( t == t_not_null ) return obj;
1380
1381 Node *cast = new CastPPNode(obj,t_not_null);
1382 cast->init_req(0, control());
1383 cast = _gvn.transform( cast );
1384
1385 // Scan for instances of 'obj' in the current JVM mapping.
1386 // These instances are known to be not-null after the test.
1387 if (do_replace_in_map)
1388 replace_in_map(obj, cast);
1389
1390 return cast; // Return casted value
1391 }
1392
1393
1394 //--------------------------replace_in_map-------------------------------------
1395 void GraphKit::replace_in_map(Node* old, Node* neww) {
1396 if (old == neww) {
1397 return;
1398 }
1399
1400 map()->replace_edge(old, neww);
1401
1402 // Note: This operation potentially replaces any edge
1403 // on the map. This includes locals, stack, and monitors
1404 // of the current (innermost) JVM state.
1405
1406 if (!ReplaceInParentMaps) {
1407 return;
1408 }
1409
1410 // PreserveJVMState doesn't do a deep copy so we can't modify
1411 // parents
1412 if (Compile::current()->has_preserve_jvm_state()) {
1413 return;
1414 }
1415
1416 Parse* parser = is_Parse();
1417 bool progress = true;
1418 Node* ctrl = map()->in(0);
1419 // Follow the chain of parsers and see whether the update can be
1420 // done in the map of callers. We can do the replace for a caller if
1421 // the current control post dominates the control of a caller.
1422 while (parser != NULL && parser->caller() != NULL && progress) {
1423 progress = false;
1424 Node* parent_map = parser->caller()->map();
1425 assert(parser->exits().map()->jvms()->depth() == parser->caller()->depth(), "map mismatch");
1426
1427 Node* parent_ctrl = parent_map->in(0);
1428
1429 while (parent_ctrl->is_Region()) {
1430 Node* n = parent_ctrl->as_Region()->is_copy();
1431 if (n == NULL) {
1432 break;
1433 }
1434 parent_ctrl = n;
1435 }
1436
1437 for (;;) {
1438 if (ctrl == parent_ctrl) {
1439 // update the map of the exits which is the one that will be
1440 // used when compilation resume after inlining
1441 parser->exits().map()->replace_edge(old, neww);
1442 progress = true;
1443 break;
1444 }
1445 if (ctrl->is_Proj() && ctrl->as_Proj()->is_uncommon_trap_if_pattern(Deoptimization::Reason_none)) {
1446 ctrl = ctrl->in(0)->in(0);
1447 } else if (ctrl->is_Region()) {
1448 Node* n = ctrl->as_Region()->is_copy();
1449 if (n == NULL) {
1450 break;
1451 }
1452 ctrl = n;
1453 } else {
1454 break;
1455 }
1456 }
1457
1458 parser = parser->parent_parser();
1459 }
1460 }
1461
1462
1463 //=============================================================================
1464 //--------------------------------memory---------------------------------------
1465 Node* GraphKit::memory(uint alias_idx) {
1466 MergeMemNode* mem = merged_memory();
1467 Node* p = mem->memory_at(alias_idx);
1468 _gvn.set_type(p, Type::MEMORY); // must be mapped
1469 return p;
1470 }
1471
1472 //-----------------------------reset_memory------------------------------------
1473 Node* GraphKit::reset_memory() {
1474 Node* mem = map()->memory();
1475 // do not use this node for any more parsing!
1476 debug_only( map()->set_memory((Node*)NULL) );
1477 return _gvn.transform( mem );
1478 }
1479
1480 //------------------------------set_all_memory---------------------------------
1481 void GraphKit::set_all_memory(Node* newmem) {
1482 Node* mergemem = MergeMemNode::make(C, newmem);
1483 gvn().set_type_bottom(mergemem);
1484 map()->set_memory(mergemem);
1485 }
1486
1487 //------------------------------set_all_memory_call----------------------------
1488 void GraphKit::set_all_memory_call(Node* call, bool separate_io_proj) {
1489 Node* newmem = _gvn.transform( new ProjNode(call, TypeFunc::Memory, separate_io_proj) );
1490 set_all_memory(newmem);
1491 }
1492
1493 //=============================================================================
1494 //
1495 // parser factory methods for MemNodes
1496 //
1497 // These are layered on top of the factory methods in LoadNode and StoreNode,
1498 // and integrate with the parser's memory state and _gvn engine.
1499 //
1500
1501 // factory methods in "int adr_idx"
1502 Node* GraphKit::make_load(Node* ctl, Node* adr, const Type* t, BasicType bt,
1503 int adr_idx,
1504 MemNode::MemOrd mo, bool require_atomic_access) {
1505 assert(adr_idx != Compile::AliasIdxTop, "use other make_load factory" );
1506 const TypePtr* adr_type = NULL; // debug-mode-only argument
1507 debug_only(adr_type = C->get_adr_type(adr_idx));
1508 Node* mem = memory(adr_idx);
1509 Node* ld;
1510 if (require_atomic_access && bt == T_LONG) {
1511 ld = LoadLNode::make_atomic(C, ctl, mem, adr, adr_type, t, mo);
1512 } else if (require_atomic_access && bt == T_DOUBLE) {
1513 ld = LoadDNode::make_atomic(C, ctl, mem, adr, adr_type, t, mo);
1514 } else {
1515 ld = LoadNode::make(_gvn, ctl, mem, adr, adr_type, t, bt, mo);
1516 }
1517 ld = _gvn.transform(ld);
1518 if ((bt == T_OBJECT) && C->do_escape_analysis() || C->eliminate_boxing()) {
1519 // Improve graph before escape analysis and boxing elimination.
1520 record_for_igvn(ld);
1521 }
1522 return ld;
1523 }
1524
1525 Node* GraphKit::store_to_memory(Node* ctl, Node* adr, Node *val, BasicType bt,
1526 int adr_idx,
1527 MemNode::MemOrd mo,
1528 bool require_atomic_access) {
1529 assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1530 const TypePtr* adr_type = NULL;
1531 debug_only(adr_type = C->get_adr_type(adr_idx));
1532 Node *mem = memory(adr_idx);
1533 Node* st;
1534 if (require_atomic_access && bt == T_LONG) {
1535 st = StoreLNode::make_atomic(C, ctl, mem, adr, adr_type, val, mo);
1536 } else if (require_atomic_access && bt == T_DOUBLE) {
1537 st = StoreDNode::make_atomic(C, ctl, mem, adr, adr_type, val, mo);
1538 } else {
1539 st = StoreNode::make(_gvn, ctl, mem, adr, adr_type, val, bt, mo);
1540 }
1541 st = _gvn.transform(st);
1542 set_memory(st, adr_idx);
1543 // Back-to-back stores can only remove intermediate store with DU info
1544 // so push on worklist for optimizer.
1545 if (mem->req() > MemNode::Address && adr == mem->in(MemNode::Address))
1546 record_for_igvn(st);
1547
1548 return st;
1549 }
1550
1551
1552 void GraphKit::pre_barrier(bool do_load,
1553 Node* ctl,
1554 Node* obj,
1555 Node* adr,
1556 uint adr_idx,
1557 Node* val,
1558 const TypeOopPtr* val_type,
1559 Node* pre_val,
1560 BasicType bt) {
1561
1562 BarrierSet* bs = Universe::heap()->barrier_set();
1563 set_control(ctl);
1564 switch (bs->kind()) {
1565 case BarrierSet::G1SATBCT:
1566 case BarrierSet::G1SATBCTLogging:
1567 g1_write_barrier_pre(do_load, obj, adr, adr_idx, val, val_type, pre_val, bt);
1568 break;
1569
1570 case BarrierSet::CardTableModRef:
1571 case BarrierSet::CardTableExtension:
1572 case BarrierSet::ModRef:
1573 break;
1574
1575 case BarrierSet::Other:
1576 default :
1577 ShouldNotReachHere();
1578
1579 }
1580 }
1581
1582 bool GraphKit::can_move_pre_barrier() const {
1583 BarrierSet* bs = Universe::heap()->barrier_set();
1584 switch (bs->kind()) {
1585 case BarrierSet::G1SATBCT:
1586 case BarrierSet::G1SATBCTLogging:
1587 return true; // Can move it if no safepoint
1588
1589 case BarrierSet::CardTableModRef:
1590 case BarrierSet::CardTableExtension:
1591 case BarrierSet::ModRef:
1592 return true; // There is no pre-barrier
1593
1594 case BarrierSet::Other:
1595 default :
1596 ShouldNotReachHere();
1597 }
1598 return false;
1599 }
1600
1601 void GraphKit::post_barrier(Node* ctl,
1602 Node* store,
1603 Node* obj,
1604 Node* adr,
1605 uint adr_idx,
1606 Node* val,
1607 BasicType bt,
1608 bool use_precise) {
1609 BarrierSet* bs = Universe::heap()->barrier_set();
1610 set_control(ctl);
1611 switch (bs->kind()) {
1612 case BarrierSet::G1SATBCT:
1613 case BarrierSet::G1SATBCTLogging:
1614 g1_write_barrier_post(store, obj, adr, adr_idx, val, bt, use_precise);
1615 break;
1616
1617 case BarrierSet::CardTableModRef:
1618 case BarrierSet::CardTableExtension:
1619 write_barrier_post(store, obj, adr, adr_idx, val, use_precise);
1620 break;
1621
1622 case BarrierSet::ModRef:
1623 break;
1624
1625 case BarrierSet::Other:
1626 default :
1627 ShouldNotReachHere();
1628
1629 }
1630 }
1631
1632 Node* GraphKit::store_oop(Node* ctl,
1633 Node* obj,
1634 Node* adr,
1635 const TypePtr* adr_type,
1636 Node* val,
1637 const TypeOopPtr* val_type,
1638 BasicType bt,
1639 bool use_precise,
1640 MemNode::MemOrd mo) {
1641 // Transformation of a value which could be NULL pointer (CastPP #NULL)
1642 // could be delayed during Parse (for example, in adjust_map_after_if()).
1643 // Execute transformation here to avoid barrier generation in such case.
1644 if (_gvn.type(val) == TypePtr::NULL_PTR)
1645 val = _gvn.makecon(TypePtr::NULL_PTR);
1646
1647 set_control(ctl);
1648 if (stopped()) return top(); // Dead path ?
1649
1650 assert(bt == T_OBJECT, "sanity");
1651 assert(val != NULL, "not dead path");
1652 uint adr_idx = C->get_alias_index(adr_type);
1653 assert(adr_idx != Compile::AliasIdxTop, "use other store_to_memory factory" );
1654
1655 pre_barrier(true /* do_load */,
1656 control(), obj, adr, adr_idx, val, val_type,
1657 NULL /* pre_val */,
1658 bt);
1659
1660 Node* store = store_to_memory(control(), adr, val, bt, adr_idx, mo);
1661 post_barrier(control(), store, obj, adr, adr_idx, val, bt, use_precise);
1662 return store;
1663 }
1664
1665 // Could be an array or object we don't know at compile time (unsafe ref.)
1666 Node* GraphKit::store_oop_to_unknown(Node* ctl,
1667 Node* obj, // containing obj
1668 Node* adr, // actual adress to store val at
1669 const TypePtr* adr_type,
1670 Node* val,
1671 BasicType bt,
1672 MemNode::MemOrd mo) {
1673 Compile::AliasType* at = C->alias_type(adr_type);
1674 const TypeOopPtr* val_type = NULL;
1675 if (adr_type->isa_instptr()) {
1676 if (at->field() != NULL) {
1677 // known field. This code is a copy of the do_put_xxx logic.
1678 ciField* field = at->field();
1679 if (!field->type()->is_loaded()) {
1680 val_type = TypeInstPtr::BOTTOM;
1681 } else {
1682 val_type = TypeOopPtr::make_from_klass(field->type()->as_klass());
1683 }
1684 }
1685 } else if (adr_type->isa_aryptr()) {
1686 val_type = adr_type->is_aryptr()->elem()->make_oopptr();
1687 }
1688 if (val_type == NULL) {
1689 val_type = TypeInstPtr::BOTTOM;
1690 }
1691 return store_oop(ctl, obj, adr, adr_type, val, val_type, bt, true, mo);
1692 }
1693
1694
1695 //-------------------------array_element_address-------------------------
1696 Node* GraphKit::array_element_address(Node* ary, Node* idx, BasicType elembt,
1697 const TypeInt* sizetype) {
1698 uint shift = exact_log2(type2aelembytes(elembt));
1699 uint header = arrayOopDesc::base_offset_in_bytes(elembt);
1700
1701 // short-circuit a common case (saves lots of confusing waste motion)
1702 jint idx_con = find_int_con(idx, -1);
1703 if (idx_con >= 0) {
1704 intptr_t offset = header + ((intptr_t)idx_con << shift);
1705 return basic_plus_adr(ary, offset);
1706 }
1707
1708 // must be correct type for alignment purposes
1709 Node* base = basic_plus_adr(ary, header);
1710 #ifdef _LP64
1711 // The scaled index operand to AddP must be a clean 64-bit value.
1712 // Java allows a 32-bit int to be incremented to a negative
1713 // value, which appears in a 64-bit register as a large
1714 // positive number. Using that large positive number as an
1715 // operand in pointer arithmetic has bad consequences.
1716 // On the other hand, 32-bit overflow is rare, and the possibility
1717 // can often be excluded, if we annotate the ConvI2L node with
1718 // a type assertion that its value is known to be a small positive
1719 // number. (The prior range check has ensured this.)
1720 // This assertion is used by ConvI2LNode::Ideal.
1721 int index_max = max_jint - 1; // array size is max_jint, index is one less
1722 if (sizetype != NULL) index_max = sizetype->_hi - 1;
1723 const TypeLong* lidxtype = TypeLong::make(CONST64(0), index_max, Type::WidenMax);
1724 idx = _gvn.transform( new ConvI2LNode(idx, lidxtype) );
1725 #endif
1726 Node* scale = _gvn.transform( new LShiftXNode(idx, intcon(shift)) );
1727 return basic_plus_adr(ary, base, scale);
1728 }
1729
1730 //-------------------------load_array_element-------------------------
1731 Node* GraphKit::load_array_element(Node* ctl, Node* ary, Node* idx, const TypeAryPtr* arytype) {
1732 const Type* elemtype = arytype->elem();
1733 BasicType elembt = elemtype->array_element_basic_type();
1734 Node* adr = array_element_address(ary, idx, elembt, arytype->size());
1735 Node* ld = make_load(ctl, adr, elemtype, elembt, arytype, MemNode::unordered);
1736 return ld;
1737 }
1738
1739 //-------------------------set_arguments_for_java_call-------------------------
1740 // Arguments (pre-popped from the stack) are taken from the JVMS.
1741 void GraphKit::set_arguments_for_java_call(CallJavaNode* call) {
1742 // Add the call arguments:
1743 uint nargs = call->method()->arg_size();
1744 for (uint i = 0; i < nargs; i++) {
1745 Node* arg = argument(i);
1746 call->init_req(i + TypeFunc::Parms, arg);
1747 }
1748 }
1749
1750 //---------------------------set_edges_for_java_call---------------------------
1751 // Connect a newly created call into the current JVMS.
1752 // A return value node (if any) is returned from set_edges_for_java_call.
1753 void GraphKit::set_edges_for_java_call(CallJavaNode* call, bool must_throw, bool separate_io_proj) {
1754
1755 // Add the predefined inputs:
1756 call->init_req( TypeFunc::Control, control() );
1757 call->init_req( TypeFunc::I_O , i_o() );
1758 call->init_req( TypeFunc::Memory , reset_memory() );
1759 call->init_req( TypeFunc::FramePtr, frameptr() );
1760 call->init_req( TypeFunc::ReturnAdr, top() );
1761
1762 add_safepoint_edges(call, must_throw);
1763
1764 Node* xcall = _gvn.transform(call);
1765
1766 if (xcall == top()) {
1767 set_control(top());
1768 return;
1769 }
1770 assert(xcall == call, "call identity is stable");
1771
1772 // Re-use the current map to produce the result.
1773
1774 set_control(_gvn.transform(new ProjNode(call, TypeFunc::Control)));
1775 set_i_o( _gvn.transform(new ProjNode(call, TypeFunc::I_O , separate_io_proj)));
1776 set_all_memory_call(xcall, separate_io_proj);
1777
1778 //return xcall; // no need, caller already has it
1779 }
1780
1781 Node* GraphKit::set_results_for_java_call(CallJavaNode* call, bool separate_io_proj) {
1782 if (stopped()) return top(); // maybe the call folded up?
1783
1784 // Capture the return value, if any.
1785 Node* ret;
1786 if (call->method() == NULL ||
1787 call->method()->return_type()->basic_type() == T_VOID)
1788 ret = top();
1789 else ret = _gvn.transform(new ProjNode(call, TypeFunc::Parms));
1790
1791 // Note: Since any out-of-line call can produce an exception,
1792 // we always insert an I_O projection from the call into the result.
1793
1794 make_slow_call_ex(call, env()->Throwable_klass(), separate_io_proj);
1795
1796 if (separate_io_proj) {
1797 // The caller requested separate projections be used by the fall
1798 // through and exceptional paths, so replace the projections for
1799 // the fall through path.
1800 set_i_o(_gvn.transform( new ProjNode(call, TypeFunc::I_O) ));
1801 set_all_memory(_gvn.transform( new ProjNode(call, TypeFunc::Memory) ));
1802 }
1803 return ret;
1804 }
1805
1806 //--------------------set_predefined_input_for_runtime_call--------------------
1807 // Reading and setting the memory state is way conservative here.
1808 // The real problem is that I am not doing real Type analysis on memory,
1809 // so I cannot distinguish card mark stores from other stores. Across a GC
1810 // point the Store Barrier and the card mark memory has to agree. I cannot
1811 // have a card mark store and its barrier split across the GC point from
1812 // either above or below. Here I get that to happen by reading ALL of memory.
1813 // A better answer would be to separate out card marks from other memory.
1814 // For now, return the input memory state, so that it can be reused
1815 // after the call, if this call has restricted memory effects.
1816 Node* GraphKit::set_predefined_input_for_runtime_call(SafePointNode* call) {
1817 // Set fixed predefined input arguments
1818 Node* memory = reset_memory();
1819 call->init_req( TypeFunc::Control, control() );
1820 call->init_req( TypeFunc::I_O, top() ); // does no i/o
1821 call->init_req( TypeFunc::Memory, memory ); // may gc ptrs
1822 call->init_req( TypeFunc::FramePtr, frameptr() );
1823 call->init_req( TypeFunc::ReturnAdr, top() );
1824 return memory;
1825 }
1826
1827 //-------------------set_predefined_output_for_runtime_call--------------------
1828 // Set control and memory (not i_o) from the call.
1829 // If keep_mem is not NULL, use it for the output state,
1830 // except for the RawPtr output of the call, if hook_mem is TypeRawPtr::BOTTOM.
1831 // If hook_mem is NULL, this call produces no memory effects at all.
1832 // If hook_mem is a Java-visible memory slice (such as arraycopy operands),
1833 // then only that memory slice is taken from the call.
1834 // In the last case, we must put an appropriate memory barrier before
1835 // the call, so as to create the correct anti-dependencies on loads
1836 // preceding the call.
1837 void GraphKit::set_predefined_output_for_runtime_call(Node* call,
1838 Node* keep_mem,
1839 const TypePtr* hook_mem) {
1840 // no i/o
1841 set_control(_gvn.transform( new ProjNode(call,TypeFunc::Control) ));
1842 if (keep_mem) {
1843 // First clone the existing memory state
1844 set_all_memory(keep_mem);
1845 if (hook_mem != NULL) {
1846 // Make memory for the call
1847 Node* mem = _gvn.transform( new ProjNode(call, TypeFunc::Memory) );
1848 // Set the RawPtr memory state only. This covers all the heap top/GC stuff
1849 // We also use hook_mem to extract specific effects from arraycopy stubs.
1850 set_memory(mem, hook_mem);
1851 }
1852 // ...else the call has NO memory effects.
1853
1854 // Make sure the call advertises its memory effects precisely.
1855 // This lets us build accurate anti-dependences in gcm.cpp.
1856 assert(C->alias_type(call->adr_type()) == C->alias_type(hook_mem),
1857 "call node must be constructed correctly");
1858 } else {
1859 assert(hook_mem == NULL, "");
1860 // This is not a "slow path" call; all memory comes from the call.
1861 set_all_memory_call(call);
1862 }
1863 }
1864
1865
1866 // Replace the call with the current state of the kit.
1867 void GraphKit::replace_call(CallNode* call, Node* result) {
1868 JVMState* ejvms = NULL;
1869 if (has_exceptions()) {
1870 ejvms = transfer_exceptions_into_jvms();
1871 }
1872
1873 SafePointNode* final_state = stop();
1874
1875 // Find all the needed outputs of this call
1876 CallProjections callprojs;
1877 call->extract_projections(&callprojs, true);
1878
1879 Node* init_mem = call->in(TypeFunc::Memory);
1880 Node* final_mem = final_state->in(TypeFunc::Memory);
1881 Node* final_ctl = final_state->in(TypeFunc::Control);
1882 Node* final_io = final_state->in(TypeFunc::I_O);
1883
1884 // Replace all the old call edges with the edges from the inlining result
1885 if (callprojs.fallthrough_catchproj != NULL) {
1886 C->gvn_replace_by(callprojs.fallthrough_catchproj, final_ctl);
1887 }
1888 if (callprojs.fallthrough_memproj != NULL) {
1889 C->gvn_replace_by(callprojs.fallthrough_memproj, final_mem);
1890 }
1891 if (callprojs.fallthrough_ioproj != NULL) {
1892 C->gvn_replace_by(callprojs.fallthrough_ioproj, final_io);
1893 }
1894
1895 // Replace the result with the new result if it exists and is used
1896 if (callprojs.resproj != NULL && result != NULL) {
1897 C->gvn_replace_by(callprojs.resproj, result);
1898 }
1899
1900 if (ejvms == NULL) {
1901 // No exception edges to simply kill off those paths
1902 if (callprojs.catchall_catchproj != NULL) {
1903 C->gvn_replace_by(callprojs.catchall_catchproj, C->top());
1904 }
1905 if (callprojs.catchall_memproj != NULL) {
1906 C->gvn_replace_by(callprojs.catchall_memproj, C->top());
1907 }
1908 if (callprojs.catchall_ioproj != NULL) {
1909 C->gvn_replace_by(callprojs.catchall_ioproj, C->top());
1910 }
1911 // Replace the old exception object with top
1912 if (callprojs.exobj != NULL) {
1913 C->gvn_replace_by(callprojs.exobj, C->top());
1914 }
1915 } else {
1916 GraphKit ekit(ejvms);
1917
1918 // Load my combined exception state into the kit, with all phis transformed:
1919 SafePointNode* ex_map = ekit.combine_and_pop_all_exception_states();
1920
1921 Node* ex_oop = ekit.use_exception_state(ex_map);
1922 if (callprojs.catchall_catchproj != NULL) {
1923 C->gvn_replace_by(callprojs.catchall_catchproj, ekit.control());
1924 }
1925 if (callprojs.catchall_memproj != NULL) {
1926 C->gvn_replace_by(callprojs.catchall_memproj, ekit.reset_memory());
1927 }
1928 if (callprojs.catchall_ioproj != NULL) {
1929 C->gvn_replace_by(callprojs.catchall_ioproj, ekit.i_o());
1930 }
1931
1932 // Replace the old exception object with the newly created one
1933 if (callprojs.exobj != NULL) {
1934 C->gvn_replace_by(callprojs.exobj, ex_oop);
1935 }
1936 }
1937
1938 // Disconnect the call from the graph
1939 call->disconnect_inputs(NULL, C);
1940 C->gvn_replace_by(call, C->top());
1941
1942 // Clean up any MergeMems that feed other MergeMems since the
1943 // optimizer doesn't like that.
1944 if (final_mem->is_MergeMem()) {
1945 Node_List wl;
1946 for (SimpleDUIterator i(final_mem); i.has_next(); i.next()) {
1947 Node* m = i.get();
1948 if (m->is_MergeMem() && !wl.contains(m)) {
1949 wl.push(m);
1950 }
1951 }
1952 while (wl.size() > 0) {
1953 _gvn.transform(wl.pop());
1954 }
1955 }
1956 }
1957
1958
1959 //------------------------------increment_counter------------------------------
1960 // for statistics: increment a VM counter by 1
1961
1962 void GraphKit::increment_counter(address counter_addr) {
1963 Node* adr1 = makecon(TypeRawPtr::make(counter_addr));
1964 increment_counter(adr1);
1965 }
1966
1967 void GraphKit::increment_counter(Node* counter_addr) {
1968 int adr_type = Compile::AliasIdxRaw;
1969 Node* ctrl = control();
1970 Node* cnt = make_load(ctrl, counter_addr, TypeInt::INT, T_INT, adr_type, MemNode::unordered);
1971 Node* incr = _gvn.transform(new AddINode(cnt, _gvn.intcon(1)));
1972 store_to_memory(ctrl, counter_addr, incr, T_INT, adr_type, MemNode::unordered);
1973 }
1974
1975
1976 //------------------------------uncommon_trap----------------------------------
1977 // Bail out to the interpreter in mid-method. Implemented by calling the
1978 // uncommon_trap blob. This helper function inserts a runtime call with the
1979 // right debug info.
1980 void GraphKit::uncommon_trap(int trap_request,
1981 ciKlass* klass, const char* comment,
1982 bool must_throw,
1983 bool keep_exact_action) {
1984 if (failing()) stop();
1985 if (stopped()) return; // trap reachable?
1986
1987 // Note: If ProfileTraps is true, and if a deopt. actually
1988 // occurs here, the runtime will make sure an MDO exists. There is
1989 // no need to call method()->ensure_method_data() at this point.
1990
1991 // Set the stack pointer to the right value for reexecution:
1992 set_sp(reexecute_sp());
1993
1994 #ifdef ASSERT
1995 if (!must_throw) {
1996 // Make sure the stack has at least enough depth to execute
1997 // the current bytecode.
1998 int inputs, ignored_depth;
1999 if (compute_stack_effects(inputs, ignored_depth)) {
2000 assert(sp() >= inputs, err_msg_res("must have enough JVMS stack to execute %s: sp=%d, inputs=%d",
2001 Bytecodes::name(java_bc()), sp(), inputs));
2002 }
2003 }
2004 #endif
2005
2006 Deoptimization::DeoptReason reason = Deoptimization::trap_request_reason(trap_request);
2007 Deoptimization::DeoptAction action = Deoptimization::trap_request_action(trap_request);
2008
2009 switch (action) {
2010 case Deoptimization::Action_maybe_recompile:
2011 case Deoptimization::Action_reinterpret:
2012 // Temporary fix for 6529811 to allow virtual calls to be sure they
2013 // get the chance to go from mono->bi->mega
2014 if (!keep_exact_action &&
2015 Deoptimization::trap_request_index(trap_request) < 0 &&
2016 too_many_recompiles(reason)) {
2017 // This BCI is causing too many recompilations.
2018 action = Deoptimization::Action_none;
2019 trap_request = Deoptimization::make_trap_request(reason, action);
2020 } else {
2021 C->set_trap_can_recompile(true);
2022 }
2023 break;
2024 case Deoptimization::Action_make_not_entrant:
2025 C->set_trap_can_recompile(true);
2026 break;
2027 #ifdef ASSERT
2028 case Deoptimization::Action_none:
2029 case Deoptimization::Action_make_not_compilable:
2030 break;
2031 default:
2032 fatal(err_msg_res("unknown action %d: %s", action, Deoptimization::trap_action_name(action)));
2033 break;
2034 #endif
2035 }
2036
2037 if (TraceOptoParse) {
2038 char buf[100];
2039 tty->print_cr("Uncommon trap %s at bci:%d",
2040 Deoptimization::format_trap_request(buf, sizeof(buf),
2041 trap_request), bci());
2042 }
2043
2044 CompileLog* log = C->log();
2045 if (log != NULL) {
2046 int kid = (klass == NULL)? -1: log->identify(klass);
2047 log->begin_elem("uncommon_trap bci='%d'", bci());
2048 char buf[100];
2049 log->print(" %s", Deoptimization::format_trap_request(buf, sizeof(buf),
2050 trap_request));
2051 if (kid >= 0) log->print(" klass='%d'", kid);
2052 if (comment != NULL) log->print(" comment='%s'", comment);
2053 log->end_elem();
2054 }
2055
2056 // Make sure any guarding test views this path as very unlikely
2057 Node *i0 = control()->in(0);
2058 if (i0 != NULL && i0->is_If()) { // Found a guarding if test?
2059 IfNode *iff = i0->as_If();
2060 float f = iff->_prob; // Get prob
2061 if (control()->Opcode() == Op_IfTrue) {
2062 if (f > PROB_UNLIKELY_MAG(4))
2063 iff->_prob = PROB_MIN;
2064 } else {
2065 if (f < PROB_LIKELY_MAG(4))
2066 iff->_prob = PROB_MAX;
2067 }
2068 }
2069
2070 // Clear out dead values from the debug info.
2071 kill_dead_locals();
2072
2073 // Now insert the uncommon trap subroutine call
2074 address call_addr = SharedRuntime::uncommon_trap_blob()->entry_point();
2075 const TypePtr* no_memory_effects = NULL;
2076 // Pass the index of the class to be loaded
2077 Node* call = make_runtime_call(RC_NO_LEAF | RC_UNCOMMON |
2078 (must_throw ? RC_MUST_THROW : 0),
2079 OptoRuntime::uncommon_trap_Type(),
2080 call_addr, "uncommon_trap", no_memory_effects,
2081 intcon(trap_request));
2082 assert(call->as_CallStaticJava()->uncommon_trap_request() == trap_request,
2083 "must extract request correctly from the graph");
2084 assert(trap_request != 0, "zero value reserved by uncommon_trap_request");
2085
2086 call->set_req(TypeFunc::ReturnAdr, returnadr());
2087 // The debug info is the only real input to this call.
2088
2089 // Halt-and-catch fire here. The above call should never return!
2090 HaltNode* halt = new HaltNode(control(), frameptr());
2091 _gvn.set_type_bottom(halt);
2092 root()->add_req(halt);
2093
2094 stop_and_kill_map();
2095 }
2096
2097
2098 //--------------------------just_allocated_object------------------------------
2099 // Report the object that was just allocated.
2100 // It must be the case that there are no intervening safepoints.
2101 // We use this to determine if an object is so "fresh" that
2102 // it does not require card marks.
2103 Node* GraphKit::just_allocated_object(Node* current_control) {
2104 if (C->recent_alloc_ctl() == current_control)
2105 return C->recent_alloc_obj();
2106 return NULL;
2107 }
2108
2109
2110 void GraphKit::round_double_arguments(ciMethod* dest_method) {
2111 // (Note: TypeFunc::make has a cache that makes this fast.)
2112 const TypeFunc* tf = TypeFunc::make(dest_method);
2113 int nargs = tf->_domain->_cnt - TypeFunc::Parms;
2114 for (int j = 0; j < nargs; j++) {
2115 const Type *targ = tf->_domain->field_at(j + TypeFunc::Parms);
2116 if( targ->basic_type() == T_DOUBLE ) {
2117 // If any parameters are doubles, they must be rounded before
2118 // the call, dstore_rounding does gvn.transform
2119 Node *arg = argument(j);
2120 arg = dstore_rounding(arg);
2121 set_argument(j, arg);
2122 }
2123 }
2124 }
2125
2126 /**
2127 * Record profiling data exact_kls for Node n with the type system so
2128 * that it can propagate it (speculation)
2129 *
2130 * @param n node that the type applies to
2131 * @param exact_kls type from profiling
2132 * @param maybe_null did profiling see null?
2133 *
2134 * @return node with improved type
2135 */
2136 Node* GraphKit::record_profile_for_speculation(Node* n, ciKlass* exact_kls, bool maybe_null) {
2137 const Type* current_type = _gvn.type(n);
2138 assert(UseTypeSpeculation, "type speculation must be on");
2139
2140 const TypePtr* speculative = current_type->speculative();
2141
2142 // Should the klass from the profile be recorded in the speculative type?
2143 if (current_type->would_improve_type(exact_kls, jvms()->depth())) {
2144 const TypeKlassPtr* tklass = TypeKlassPtr::make(exact_kls);
2145 const TypeOopPtr* xtype = tklass->as_instance_type();
2146 assert(xtype->klass_is_exact(), "Should be exact");
2147 // Any reason to believe n is not null (from this profiling or a previous one)?
2148 const TypePtr* ptr = (maybe_null && current_type->speculative_maybe_null()) ? TypePtr::BOTTOM : TypePtr::NOTNULL;
2149 // record the new speculative type's depth
2150 speculative = xtype->cast_to_ptr_type(ptr->ptr())->is_ptr();
2151 speculative = speculative->with_inline_depth(jvms()->depth());
2152 } else if (current_type->would_improve_ptr(maybe_null)) {
2153 // Profiling report that null was never seen so we can change the
2154 // speculative type to non null ptr.
2155 assert(!maybe_null, "nothing to improve");
2156 if (speculative == NULL) {
2157 speculative = TypePtr::NOTNULL;
2158 } else {
2159 const TypePtr* ptr = TypePtr::NOTNULL;
2160 speculative = speculative->cast_to_ptr_type(ptr->ptr())->is_ptr();
2161 }
2162 }
2163
2164 if (speculative != current_type->speculative()) {
2165 // Build a type with a speculative type (what we think we know
2166 // about the type but will need a guard when we use it)
2167 const TypeOopPtr* spec_type = TypeOopPtr::make(TypePtr::BotPTR, Type::OffsetBot, TypeOopPtr::InstanceBot, speculative);
2168 // We're changing the type, we need a new CheckCast node to carry
2169 // the new type. The new type depends on the control: what
2170 // profiling tells us is only valid from here as far as we can
2171 // tell.
2172 Node* cast = new CheckCastPPNode(control(), n, current_type->remove_speculative()->join_speculative(spec_type));
2173 cast = _gvn.transform(cast);
2174 replace_in_map(n, cast);
2175 n = cast;
2176 }
2177
2178 return n;
2179 }
2180
2181 /**
2182 * Record profiling data from receiver profiling at an invoke with the
2183 * type system so that it can propagate it (speculation)
2184 *
2185 * @param n receiver node
2186 *
2187 * @return node with improved type
2188 */
2189 Node* GraphKit::record_profiled_receiver_for_speculation(Node* n) {
2190 if (!UseTypeSpeculation) {
2191 return n;
2192 }
2193 ciKlass* exact_kls = profile_has_unique_klass();
2194 bool maybe_null = true;
2195 if (java_bc() == Bytecodes::_checkcast ||
2196 java_bc() == Bytecodes::_instanceof ||
2197 java_bc() == Bytecodes::_aastore) {
2198 ciProfileData* data = method()->method_data()->bci_to_data(bci());
2199 bool maybe_null = data == NULL ? true : data->as_BitData()->null_seen();
2200 }
2201 return record_profile_for_speculation(n, exact_kls, maybe_null);
2202 return n;
2203 }
2204
2205 /**
2206 * Record profiling data from argument profiling at an invoke with the
2207 * type system so that it can propagate it (speculation)
2208 *
2209 * @param dest_method target method for the call
2210 * @param bc what invoke bytecode is this?
2211 */
2212 void GraphKit::record_profiled_arguments_for_speculation(ciMethod* dest_method, Bytecodes::Code bc) {
2213 if (!UseTypeSpeculation) {
2214 return;
2215 }
2216 const TypeFunc* tf = TypeFunc::make(dest_method);
2217 int nargs = tf->_domain->_cnt - TypeFunc::Parms;
2218 int skip = Bytecodes::has_receiver(bc) ? 1 : 0;
2219 for (int j = skip, i = 0; j < nargs && i < TypeProfileArgsLimit; j++) {
2220 const Type *targ = tf->_domain->field_at(j + TypeFunc::Parms);
2221 if (targ->basic_type() == T_OBJECT || targ->basic_type() == T_ARRAY) {
2222 bool maybe_null = true;
2223 ciKlass* better_type = NULL;
2224 if (method()->argument_profiled_type(bci(), i, better_type, maybe_null)) {
2225 record_profile_for_speculation(argument(j), better_type, maybe_null);
2226 }
2227 i++;
2228 }
2229 }
2230 }
2231
2232 /**
2233 * Record profiling data from parameter profiling at an invoke with
2234 * the type system so that it can propagate it (speculation)
2235 */
2236 void GraphKit::record_profiled_parameters_for_speculation() {
2237 if (!UseTypeSpeculation) {
2238 return;
2239 }
2240 for (int i = 0, j = 0; i < method()->arg_size() ; i++) {
2241 if (_gvn.type(local(i))->isa_oopptr()) {
2242 bool maybe_null = true;
2243 ciKlass* better_type = NULL;
2244 if (method()->parameter_profiled_type(j, better_type, maybe_null)) {
2245 record_profile_for_speculation(local(i), better_type, maybe_null);
2246 }
2247 j++;
2248 }
2249 }
2250 }
2251
2252 /**
2253 * Record profiling data from return value profiling at an invoke with
2254 * the type system so that it can propagate it (speculation)
2255 */
2256 void GraphKit::record_profiled_return_for_speculation() {
2257 if (!UseTypeSpeculation) {
2258 return;
2259 }
2260 bool maybe_null = true;
2261 ciKlass* better_type = NULL;
2262 if (method()->return_profiled_type(bci(), better_type, maybe_null)) {
2263 // If profiling reports a single type for the return value,
2264 // feed it to the type system so it can propagate it as a
2265 // speculative type
2266 record_profile_for_speculation(stack(sp()-1), better_type, maybe_null);
2267 }
2268 }
2269
2270 void GraphKit::round_double_result(ciMethod* dest_method) {
2271 // A non-strict method may return a double value which has an extended
2272 // exponent, but this must not be visible in a caller which is 'strict'
2273 // If a strict caller invokes a non-strict callee, round a double result
2274
2275 BasicType result_type = dest_method->return_type()->basic_type();
2276 assert( method() != NULL, "must have caller context");
2277 if( result_type == T_DOUBLE && method()->is_strict() && !dest_method->is_strict() ) {
2278 // Destination method's return value is on top of stack
2279 // dstore_rounding() does gvn.transform
2280 Node *result = pop_pair();
2281 result = dstore_rounding(result);
2282 push_pair(result);
2283 }
2284 }
2285
2286 // rounding for strict float precision conformance
2287 Node* GraphKit::precision_rounding(Node* n) {
2288 return UseStrictFP && _method->flags().is_strict()
2289 && UseSSE == 0 && Matcher::strict_fp_requires_explicit_rounding
2290 ? _gvn.transform( new RoundFloatNode(0, n) )
2291 : n;
2292 }
2293
2294 // rounding for strict double precision conformance
2295 Node* GraphKit::dprecision_rounding(Node *n) {
2296 return UseStrictFP && _method->flags().is_strict()
2297 && UseSSE <= 1 && Matcher::strict_fp_requires_explicit_rounding
2298 ? _gvn.transform( new RoundDoubleNode(0, n) )
2299 : n;
2300 }
2301
2302 // rounding for non-strict double stores
2303 Node* GraphKit::dstore_rounding(Node* n) {
2304 return Matcher::strict_fp_requires_explicit_rounding
2305 && UseSSE <= 1
2306 ? _gvn.transform( new RoundDoubleNode(0, n) )
2307 : n;
2308 }
2309
2310 //=============================================================================
2311 // Generate a fast path/slow path idiom. Graph looks like:
2312 // [foo] indicates that 'foo' is a parameter
2313 //
2314 // [in] NULL
2315 // \ /
2316 // CmpP
2317 // Bool ne
2318 // If
2319 // / \
2320 // True False-<2>
2321 // / |
2322 // / cast_not_null
2323 // Load | | ^
2324 // [fast_test] | |
2325 // gvn to opt_test | |
2326 // / \ | <1>
2327 // True False |
2328 // | \\ |
2329 // [slow_call] \[fast_result]
2330 // Ctl Val \ \
2331 // | \ \
2332 // Catch <1> \ \
2333 // / \ ^ \ \
2334 // Ex No_Ex | \ \
2335 // | \ \ | \ <2> \
2336 // ... \ [slow_res] | | \ [null_result]
2337 // \ \--+--+--- | |
2338 // \ | / \ | /
2339 // --------Region Phi
2340 //
2341 //=============================================================================
2342 // Code is structured as a series of driver functions all called 'do_XXX' that
2343 // call a set of helper functions. Helper functions first, then drivers.
2344
2345 //------------------------------null_check_oop---------------------------------
2346 // Null check oop. Set null-path control into Region in slot 3.
2347 // Make a cast-not-nullness use the other not-null control. Return cast.
2348 Node* GraphKit::null_check_oop(Node* value, Node* *null_control,
2349 bool never_see_null,
2350 bool safe_for_replace,
2351 bool speculative) {
2352 // Initial NULL check taken path
2353 (*null_control) = top();
2354 Node* cast = null_check_common(value, T_OBJECT, false, null_control, speculative);
2355
2356 // Generate uncommon_trap:
2357 if (never_see_null && (*null_control) != top()) {
2358 // If we see an unexpected null at a check-cast we record it and force a
2359 // recompile; the offending check-cast will be compiled to handle NULLs.
2360 // If we see more than one offending BCI, then all checkcasts in the
2361 // method will be compiled to handle NULLs.
2362 PreserveJVMState pjvms(this);
2363 set_control(*null_control);
2364 replace_in_map(value, null());
2365 Deoptimization::DeoptReason reason = Deoptimization::reason_null_check(speculative);
2366 uncommon_trap(reason,
2367 Deoptimization::Action_make_not_entrant);
2368 (*null_control) = top(); // NULL path is dead
2369 }
2370 if ((*null_control) == top() && safe_for_replace) {
2371 replace_in_map(value, cast);
2372 }
2373
2374 // Cast away null-ness on the result
2375 return cast;
2376 }
2377
2378 //------------------------------opt_iff----------------------------------------
2379 // Optimize the fast-check IfNode. Set the fast-path region slot 2.
2380 // Return slow-path control.
2381 Node* GraphKit::opt_iff(Node* region, Node* iff) {
2382 IfNode *opt_iff = _gvn.transform(iff)->as_If();
2383
2384 // Fast path taken; set region slot 2
2385 Node *fast_taken = _gvn.transform( new IfFalseNode(opt_iff) );
2386 region->init_req(2,fast_taken); // Capture fast-control
2387
2388 // Fast path not-taken, i.e. slow path
2389 Node *slow_taken = _gvn.transform( new IfTrueNode(opt_iff) );
2390 return slow_taken;
2391 }
2392
2393 //-----------------------------make_runtime_call-------------------------------
2394 Node* GraphKit::make_runtime_call(int flags,
2395 const TypeFunc* call_type, address call_addr,
2396 const char* call_name,
2397 const TypePtr* adr_type,
2398 // The following parms are all optional.
2399 // The first NULL ends the list.
2400 Node* parm0, Node* parm1,
2401 Node* parm2, Node* parm3,
2402 Node* parm4, Node* parm5,
2403 Node* parm6, Node* parm7) {
2404 // Slow-path call
2405 bool is_leaf = !(flags & RC_NO_LEAF);
2406 bool has_io = (!is_leaf && !(flags & RC_NO_IO));
2407 if (call_name == NULL) {
2408 assert(!is_leaf, "must supply name for leaf");
2409 call_name = OptoRuntime::stub_name(call_addr);
2410 }
2411 CallNode* call;
2412 if (!is_leaf) {
2413 call = new CallStaticJavaNode(call_type, call_addr, call_name,
2414 bci(), adr_type);
2415 } else if (flags & RC_NO_FP) {
2416 call = new CallLeafNoFPNode(call_type, call_addr, call_name, adr_type);
2417 } else {
2418 call = new CallLeafNode(call_type, call_addr, call_name, adr_type);
2419 }
2420
2421 // The following is similar to set_edges_for_java_call,
2422 // except that the memory effects of the call are restricted to AliasIdxRaw.
2423
2424 // Slow path call has no side-effects, uses few values
2425 bool wide_in = !(flags & RC_NARROW_MEM);
2426 bool wide_out = (C->get_alias_index(adr_type) == Compile::AliasIdxBot);
2427
2428 Node* prev_mem = NULL;
2429 if (wide_in) {
2430 prev_mem = set_predefined_input_for_runtime_call(call);
2431 } else {
2432 assert(!wide_out, "narrow in => narrow out");
2433 Node* narrow_mem = memory(adr_type);
2434 prev_mem = reset_memory();
2435 map()->set_memory(narrow_mem);
2436 set_predefined_input_for_runtime_call(call);
2437 }
2438
2439 // Hook each parm in order. Stop looking at the first NULL.
2440 if (parm0 != NULL) { call->init_req(TypeFunc::Parms+0, parm0);
2441 if (parm1 != NULL) { call->init_req(TypeFunc::Parms+1, parm1);
2442 if (parm2 != NULL) { call->init_req(TypeFunc::Parms+2, parm2);
2443 if (parm3 != NULL) { call->init_req(TypeFunc::Parms+3, parm3);
2444 if (parm4 != NULL) { call->init_req(TypeFunc::Parms+4, parm4);
2445 if (parm5 != NULL) { call->init_req(TypeFunc::Parms+5, parm5);
2446 if (parm6 != NULL) { call->init_req(TypeFunc::Parms+6, parm6);
2447 if (parm7 != NULL) { call->init_req(TypeFunc::Parms+7, parm7);
2448 /* close each nested if ===> */ } } } } } } } }
2449 assert(call->in(call->req()-1) != NULL, "must initialize all parms");
2450
2451 if (!is_leaf) {
2452 // Non-leaves can block and take safepoints:
2453 add_safepoint_edges(call, ((flags & RC_MUST_THROW) != 0));
2454 }
2455 // Non-leaves can throw exceptions:
2456 if (has_io) {
2457 call->set_req(TypeFunc::I_O, i_o());
2458 }
2459
2460 if (flags & RC_UNCOMMON) {
2461 // Set the count to a tiny probability. Cf. Estimate_Block_Frequency.
2462 // (An "if" probability corresponds roughly to an unconditional count.
2463 // Sort of.)
2464 call->set_cnt(PROB_UNLIKELY_MAG(4));
2465 }
2466
2467 Node* c = _gvn.transform(call);
2468 assert(c == call, "cannot disappear");
2469
2470 if (wide_out) {
2471 // Slow path call has full side-effects.
2472 set_predefined_output_for_runtime_call(call);
2473 } else {
2474 // Slow path call has few side-effects, and/or sets few values.
2475 set_predefined_output_for_runtime_call(call, prev_mem, adr_type);
2476 }
2477
2478 if (has_io) {
2479 set_i_o(_gvn.transform(new ProjNode(call, TypeFunc::I_O)));
2480 }
2481 return call;
2482
2483 }
2484
2485 //------------------------------merge_memory-----------------------------------
2486 // Merge memory from one path into the current memory state.
2487 void GraphKit::merge_memory(Node* new_mem, Node* region, int new_path) {
2488 for (MergeMemStream mms(merged_memory(), new_mem->as_MergeMem()); mms.next_non_empty2(); ) {
2489 Node* old_slice = mms.force_memory();
2490 Node* new_slice = mms.memory2();
2491 if (old_slice != new_slice) {
2492 PhiNode* phi;
2493 if (old_slice->is_Phi() && old_slice->as_Phi()->region() == region) {
2494 if (mms.is_empty()) {
2495 // clone base memory Phi's inputs for this memory slice
2496 assert(old_slice == mms.base_memory(), "sanity");
2497 phi = PhiNode::make(region, NULL, Type::MEMORY, mms.adr_type(C));
2498 _gvn.set_type(phi, Type::MEMORY);
2499 for (uint i = 1; i < phi->req(); i++) {
2500 phi->init_req(i, old_slice->in(i));
2501 }
2502 } else {
2503 phi = old_slice->as_Phi(); // Phi was generated already
2504 }
2505 } else {
2506 phi = PhiNode::make(region, old_slice, Type::MEMORY, mms.adr_type(C));
2507 _gvn.set_type(phi, Type::MEMORY);
2508 }
2509 phi->set_req(new_path, new_slice);
2510 mms.set_memory(phi);
2511 }
2512 }
2513 }
2514
2515 //------------------------------make_slow_call_ex------------------------------
2516 // Make the exception handler hookups for the slow call
2517 void GraphKit::make_slow_call_ex(Node* call, ciInstanceKlass* ex_klass, bool separate_io_proj) {
2518 if (stopped()) return;
2519
2520 // Make a catch node with just two handlers: fall-through and catch-all
2521 Node* i_o = _gvn.transform( new ProjNode(call, TypeFunc::I_O, separate_io_proj) );
2522 Node* catc = _gvn.transform( new CatchNode(control(), i_o, 2) );
2523 Node* norm = _gvn.transform( new CatchProjNode(catc, CatchProjNode::fall_through_index, CatchProjNode::no_handler_bci) );
2524 Node* excp = _gvn.transform( new CatchProjNode(catc, CatchProjNode::catch_all_index, CatchProjNode::no_handler_bci) );
2525
2526 { PreserveJVMState pjvms(this);
2527 set_control(excp);
2528 set_i_o(i_o);
2529
2530 if (excp != top()) {
2531 // Create an exception state also.
2532 // Use an exact type if the caller has specified a specific exception.
2533 const Type* ex_type = TypeOopPtr::make_from_klass_unique(ex_klass)->cast_to_ptr_type(TypePtr::NotNull);
2534 Node* ex_oop = new CreateExNode(ex_type, control(), i_o);
2535 add_exception_state(make_exception_state(_gvn.transform(ex_oop)));
2536 }
2537 }
2538
2539 // Get the no-exception control from the CatchNode.
2540 set_control(norm);
2541 }
2542
2543
2544 //-------------------------------gen_subtype_check-----------------------------
2545 // Generate a subtyping check. Takes as input the subtype and supertype.
2546 // Returns 2 values: sets the default control() to the true path and returns
2547 // the false path. Only reads invariant memory; sets no (visible) memory.
2548 // The PartialSubtypeCheckNode sets the hidden 1-word cache in the encoding
2549 // but that's not exposed to the optimizer. This call also doesn't take in an
2550 // Object; if you wish to check an Object you need to load the Object's class
2551 // prior to coming here.
2552 Node* GraphKit::gen_subtype_check(Node* subklass, Node* superklass) {
2553 // Fast check for identical types, perhaps identical constants.
2554 // The types can even be identical non-constants, in cases
2555 // involving Array.newInstance, Object.clone, etc.
2556 if (subklass == superklass)
2557 return top(); // false path is dead; no test needed.
2558
2559 if (_gvn.type(superklass)->singleton()) {
2560 ciKlass* superk = _gvn.type(superklass)->is_klassptr()->klass();
2561 ciKlass* subk = _gvn.type(subklass)->is_klassptr()->klass();
2562
2563 // In the common case of an exact superklass, try to fold up the
2564 // test before generating code. You may ask, why not just generate
2565 // the code and then let it fold up? The answer is that the generated
2566 // code will necessarily include null checks, which do not always
2567 // completely fold away. If they are also needless, then they turn
2568 // into a performance loss. Example:
2569 // Foo[] fa = blah(); Foo x = fa[0]; fa[1] = x;
2570 // Here, the type of 'fa' is often exact, so the store check
2571 // of fa[1]=x will fold up, without testing the nullness of x.
2572 switch (static_subtype_check(superk, subk)) {
2573 case SSC_always_false:
2574 {
2575 Node* always_fail = control();
2576 set_control(top());
2577 return always_fail;
2578 }
2579 case SSC_always_true:
2580 return top();
2581 case SSC_easy_test:
2582 {
2583 // Just do a direct pointer compare and be done.
2584 Node* cmp = _gvn.transform( new CmpPNode(subklass, superklass) );
2585 Node* bol = _gvn.transform( new BoolNode(cmp, BoolTest::eq) );
2586 IfNode* iff = create_and_xform_if(control(), bol, PROB_STATIC_FREQUENT, COUNT_UNKNOWN);
2587 set_control( _gvn.transform( new IfTrueNode (iff) ) );
2588 return _gvn.transform( new IfFalseNode(iff) );
2589 }
2590 case SSC_full_test:
2591 break;
2592 default:
2593 ShouldNotReachHere();
2594 }
2595 }
2596
2597 // %%% Possible further optimization: Even if the superklass is not exact,
2598 // if the subklass is the unique subtype of the superklass, the check
2599 // will always succeed. We could leave a dependency behind to ensure this.
2600
2601 // First load the super-klass's check-offset
2602 Node *p1 = basic_plus_adr( superklass, superklass, in_bytes(Klass::super_check_offset_offset()) );
2603 Node *chk_off = _gvn.transform(new LoadINode(NULL, memory(p1), p1, _gvn.type(p1)->is_ptr(),
2604 TypeInt::INT, MemNode::unordered));
2605 int cacheoff_con = in_bytes(Klass::secondary_super_cache_offset());
2606 bool might_be_cache = (find_int_con(chk_off, cacheoff_con) == cacheoff_con);
2607
2608 // Load from the sub-klass's super-class display list, or a 1-word cache of
2609 // the secondary superclass list, or a failing value with a sentinel offset
2610 // if the super-klass is an interface or exceptionally deep in the Java
2611 // hierarchy and we have to scan the secondary superclass list the hard way.
2612 // Worst-case type is a little odd: NULL is allowed as a result (usually
2613 // klass loads can never produce a NULL).
2614 Node *chk_off_X = ConvI2X(chk_off);
2615 Node *p2 = _gvn.transform( new AddPNode(subklass,subklass,chk_off_X) );
2616 // For some types like interfaces the following loadKlass is from a 1-word
2617 // cache which is mutable so can't use immutable memory. Other
2618 // types load from the super-class display table which is immutable.
2619 Node *kmem = might_be_cache ? memory(p2) : immutable_memory();
2620 Node *nkls = _gvn.transform( LoadKlassNode::make( _gvn, kmem, p2, _gvn.type(p2)->is_ptr(), TypeKlassPtr::OBJECT_OR_NULL ) );
2621
2622 // Compile speed common case: ARE a subtype and we canNOT fail
2623 if( superklass == nkls )
2624 return top(); // false path is dead; no test needed.
2625
2626 // See if we get an immediate positive hit. Happens roughly 83% of the
2627 // time. Test to see if the value loaded just previously from the subklass
2628 // is exactly the superklass.
2629 Node *cmp1 = _gvn.transform( new CmpPNode( superklass, nkls ) );
2630 Node *bol1 = _gvn.transform( new BoolNode( cmp1, BoolTest::eq ) );
2631 IfNode *iff1 = create_and_xform_if( control(), bol1, PROB_LIKELY(0.83f), COUNT_UNKNOWN );
2632 Node *iftrue1 = _gvn.transform( new IfTrueNode ( iff1 ) );
2633 set_control( _gvn.transform( new IfFalseNode( iff1 ) ) );
2634
2635 // Compile speed common case: Check for being deterministic right now. If
2636 // chk_off is a constant and not equal to cacheoff then we are NOT a
2637 // subklass. In this case we need exactly the 1 test above and we can
2638 // return those results immediately.
2639 if (!might_be_cache) {
2640 Node* not_subtype_ctrl = control();
2641 set_control(iftrue1); // We need exactly the 1 test above
2642 return not_subtype_ctrl;
2643 }
2644
2645 // Gather the various success & failures here
2646 RegionNode *r_ok_subtype = new RegionNode(4);
2647 record_for_igvn(r_ok_subtype);
2648 RegionNode *r_not_subtype = new RegionNode(3);
2649 record_for_igvn(r_not_subtype);
2650
2651 r_ok_subtype->init_req(1, iftrue1);
2652
2653 // Check for immediate negative hit. Happens roughly 11% of the time (which
2654 // is roughly 63% of the remaining cases). Test to see if the loaded
2655 // check-offset points into the subklass display list or the 1-element
2656 // cache. If it points to the display (and NOT the cache) and the display
2657 // missed then it's not a subtype.
2658 Node *cacheoff = _gvn.intcon(cacheoff_con);
2659 Node *cmp2 = _gvn.transform( new CmpINode( chk_off, cacheoff ) );
2660 Node *bol2 = _gvn.transform( new BoolNode( cmp2, BoolTest::ne ) );
2661 IfNode *iff2 = create_and_xform_if( control(), bol2, PROB_LIKELY(0.63f), COUNT_UNKNOWN );
2662 r_not_subtype->init_req(1, _gvn.transform( new IfTrueNode (iff2) ) );
2663 set_control( _gvn.transform( new IfFalseNode(iff2) ) );
2664
2665 // Check for self. Very rare to get here, but it is taken 1/3 the time.
2666 // No performance impact (too rare) but allows sharing of secondary arrays
2667 // which has some footprint reduction.
2668 Node *cmp3 = _gvn.transform( new CmpPNode( subklass, superklass ) );
2669 Node *bol3 = _gvn.transform( new BoolNode( cmp3, BoolTest::eq ) );
2670 IfNode *iff3 = create_and_xform_if( control(), bol3, PROB_LIKELY(0.36f), COUNT_UNKNOWN );
2671 r_ok_subtype->init_req(2, _gvn.transform( new IfTrueNode ( iff3 ) ) );
2672 set_control( _gvn.transform( new IfFalseNode( iff3 ) ) );
2673
2674 // -- Roads not taken here: --
2675 // We could also have chosen to perform the self-check at the beginning
2676 // of this code sequence, as the assembler does. This would not pay off
2677 // the same way, since the optimizer, unlike the assembler, can perform
2678 // static type analysis to fold away many successful self-checks.
2679 // Non-foldable self checks work better here in second position, because
2680 // the initial primary superclass check subsumes a self-check for most
2681 // types. An exception would be a secondary type like array-of-interface,
2682 // which does not appear in its own primary supertype display.
2683 // Finally, we could have chosen to move the self-check into the
2684 // PartialSubtypeCheckNode, and from there out-of-line in a platform
2685 // dependent manner. But it is worthwhile to have the check here,
2686 // where it can be perhaps be optimized. The cost in code space is
2687 // small (register compare, branch).
2688
2689 // Now do a linear scan of the secondary super-klass array. Again, no real
2690 // performance impact (too rare) but it's gotta be done.
2691 // Since the code is rarely used, there is no penalty for moving it
2692 // out of line, and it can only improve I-cache density.
2693 // The decision to inline or out-of-line this final check is platform
2694 // dependent, and is found in the AD file definition of PartialSubtypeCheck.
2695 Node* psc = _gvn.transform(
2696 new PartialSubtypeCheckNode(control(), subklass, superklass) );
2697
2698 Node *cmp4 = _gvn.transform( new CmpPNode( psc, null() ) );
2699 Node *bol4 = _gvn.transform( new BoolNode( cmp4, BoolTest::ne ) );
2700 IfNode *iff4 = create_and_xform_if( control(), bol4, PROB_FAIR, COUNT_UNKNOWN );
2701 r_not_subtype->init_req(2, _gvn.transform( new IfTrueNode (iff4) ) );
2702 r_ok_subtype ->init_req(3, _gvn.transform( new IfFalseNode(iff4) ) );
2703
2704 // Return false path; set default control to true path.
2705 set_control( _gvn.transform(r_ok_subtype) );
2706 return _gvn.transform(r_not_subtype);
2707 }
2708
2709 //----------------------------static_subtype_check-----------------------------
2710 // Shortcut important common cases when superklass is exact:
2711 // (0) superklass is java.lang.Object (can occur in reflective code)
2712 // (1) subklass is already limited to a subtype of superklass => always ok
2713 // (2) subklass does not overlap with superklass => always fail
2714 // (3) superklass has NO subtypes and we can check with a simple compare.
2715 int GraphKit::static_subtype_check(ciKlass* superk, ciKlass* subk) {
2716 if (StressReflectiveCode) {
2717 return SSC_full_test; // Let caller generate the general case.
2718 }
2719
2720 if (superk == env()->Object_klass()) {
2721 return SSC_always_true; // (0) this test cannot fail
2722 }
2723
2724 ciType* superelem = superk;
2725 if (superelem->is_array_klass())
2726 superelem = superelem->as_array_klass()->base_element_type();
2727
2728 if (!subk->is_interface()) { // cannot trust static interface types yet
2729 if (subk->is_subtype_of(superk)) {
2730 return SSC_always_true; // (1) false path dead; no dynamic test needed
2731 }
2732 if (!(superelem->is_klass() && superelem->as_klass()->is_interface()) &&
2733 !superk->is_subtype_of(subk)) {
2734 return SSC_always_false;
2735 }
2736 }
2737
2738 // If casting to an instance klass, it must have no subtypes
2739 if (superk->is_interface()) {
2740 // Cannot trust interfaces yet.
2741 // %%% S.B. superk->nof_implementors() == 1
2742 } else if (superelem->is_instance_klass()) {
2743 ciInstanceKlass* ik = superelem->as_instance_klass();
2744 if (!ik->has_subklass() && !ik->is_interface()) {
2745 if (!ik->is_final()) {
2746 // Add a dependency if there is a chance of a later subclass.
2747 C->dependencies()->assert_leaf_type(ik);
2748 }
2749 return SSC_easy_test; // (3) caller can do a simple ptr comparison
2750 }
2751 } else {
2752 // A primitive array type has no subtypes.
2753 return SSC_easy_test; // (3) caller can do a simple ptr comparison
2754 }
2755
2756 return SSC_full_test;
2757 }
2758
2759 // Profile-driven exact type check:
2760 Node* GraphKit::type_check_receiver(Node* receiver, ciKlass* klass,
2761 float prob,
2762 Node* *casted_receiver) {
2763 const TypeKlassPtr* tklass = TypeKlassPtr::make(klass);
2764 Node* recv_klass = load_object_klass(receiver);
2765 Node* want_klass = makecon(tklass);
2766 Node* cmp = _gvn.transform( new CmpPNode(recv_klass, want_klass) );
2767 Node* bol = _gvn.transform( new BoolNode(cmp, BoolTest::eq) );
2768 IfNode* iff = create_and_xform_if(control(), bol, prob, COUNT_UNKNOWN);
2769 set_control( _gvn.transform( new IfTrueNode (iff) ));
2770 Node* fail = _gvn.transform( new IfFalseNode(iff) );
2771
2772 const TypeOopPtr* recv_xtype = tklass->as_instance_type();
2773 assert(recv_xtype->klass_is_exact(), "");
2774
2775 // Subsume downstream occurrences of receiver with a cast to
2776 // recv_xtype, since now we know what the type will be.
2777 Node* cast = new CheckCastPPNode(control(), receiver, recv_xtype);
2778 (*casted_receiver) = _gvn.transform(cast);
2779 // (User must make the replace_in_map call.)
2780
2781 return fail;
2782 }
2783
2784
2785 //------------------------------seems_never_null-------------------------------
2786 // Use null_seen information if it is available from the profile.
2787 // If we see an unexpected null at a type check we record it and force a
2788 // recompile; the offending check will be recompiled to handle NULLs.
2789 // If we see several offending BCIs, then all checks in the
2790 // method will be recompiled.
2791 bool GraphKit::seems_never_null(Node* obj, ciProfileData* data, bool& speculating) {
2792 speculating = !_gvn.type(obj)->speculative_maybe_null();
2793 Deoptimization::DeoptReason reason = Deoptimization::reason_null_check(speculating);
2794 if (UncommonNullCast // Cutout for this technique
2795 && obj != null() // And not the -Xcomp stupid case?
2796 && !too_many_traps(reason)
2797 ) {
2798 if (speculating) {
2799 return true;
2800 }
2801 if (data == NULL)
2802 // Edge case: no mature data. Be optimistic here.
2803 return true;
2804 // If the profile has not seen a null, assume it won't happen.
2805 assert(java_bc() == Bytecodes::_checkcast ||
2806 java_bc() == Bytecodes::_instanceof ||
2807 java_bc() == Bytecodes::_aastore, "MDO must collect null_seen bit here");
2808 return !data->as_BitData()->null_seen();
2809 }
2810 speculating = false;
2811 return false;
2812 }
2813
2814 //------------------------maybe_cast_profiled_receiver-------------------------
2815 // If the profile has seen exactly one type, narrow to exactly that type.
2816 // Subsequent type checks will always fold up.
2817 Node* GraphKit::maybe_cast_profiled_receiver(Node* not_null_obj,
2818 ciKlass* require_klass,
2819 ciKlass* spec_klass,
2820 bool safe_for_replace) {
2821 if (!UseTypeProfile || !TypeProfileCasts) return NULL;
2822
2823 Deoptimization::DeoptReason reason = Deoptimization::reason_class_check(spec_klass != NULL);
2824
2825 // Make sure we haven't already deoptimized from this tactic.
2826 if (too_many_traps(reason))
2827 return NULL;
2828
2829 // (No, this isn't a call, but it's enough like a virtual call
2830 // to use the same ciMethod accessor to get the profile info...)
2831 // If we have a speculative type use it instead of profiling (which
2832 // may not help us)
2833 ciKlass* exact_kls = spec_klass == NULL ? profile_has_unique_klass() : spec_klass;
2834 if (exact_kls != NULL) {// no cast failures here
2835 if (require_klass == NULL ||
2836 static_subtype_check(require_klass, exact_kls) == SSC_always_true) {
2837 // If we narrow the type to match what the type profile sees or
2838 // the speculative type, we can then remove the rest of the
2839 // cast.
2840 // This is a win, even if the exact_kls is very specific,
2841 // because downstream operations, such as method calls,
2842 // will often benefit from the sharper type.
2843 Node* exact_obj = not_null_obj; // will get updated in place...
2844 Node* slow_ctl = type_check_receiver(exact_obj, exact_kls, 1.0,
2845 &exact_obj);
2846 { PreserveJVMState pjvms(this);
2847 set_control(slow_ctl);
2848 uncommon_trap(reason,
2849 Deoptimization::Action_maybe_recompile);
2850 }
2851 if (safe_for_replace) {
2852 replace_in_map(not_null_obj, exact_obj);
2853 }
2854 return exact_obj;
2855 }
2856 // assert(ssc == SSC_always_true)... except maybe the profile lied to us.
2857 }
2858
2859 return NULL;
2860 }
2861
2862 /**
2863 * Cast obj to type and emit guard unless we had too many traps here
2864 * already
2865 *
2866 * @param obj node being casted
2867 * @param type type to cast the node to
2868 * @param not_null true if we know node cannot be null
2869 */
2870 Node* GraphKit::maybe_cast_profiled_obj(Node* obj,
2871 ciKlass* type,
2872 bool not_null) {
2873 // type == NULL if profiling tells us this object is always null
2874 if (type != NULL) {
2875 Deoptimization::DeoptReason class_reason = Deoptimization::Reason_speculate_class_check;
2876 Deoptimization::DeoptReason null_reason = Deoptimization::Reason_speculate_null_check;
2877 if (!too_many_traps(null_reason) &&
2878 !too_many_traps(class_reason)) {
2879 Node* not_null_obj = NULL;
2880 // not_null is true if we know the object is not null and
2881 // there's no need for a null check
2882 if (!not_null) {
2883 Node* null_ctl = top();
2884 not_null_obj = null_check_oop(obj, &null_ctl, true, true, true);
2885 assert(null_ctl->is_top(), "no null control here");
2886 } else {
2887 not_null_obj = obj;
2888 }
2889
2890 Node* exact_obj = not_null_obj;
2891 ciKlass* exact_kls = type;
2892 Node* slow_ctl = type_check_receiver(exact_obj, exact_kls, 1.0,
2893 &exact_obj);
2894 {
2895 PreserveJVMState pjvms(this);
2896 set_control(slow_ctl);
2897 uncommon_trap(class_reason,
2898 Deoptimization::Action_maybe_recompile);
2899 }
2900 replace_in_map(not_null_obj, exact_obj);
2901 obj = exact_obj;
2902 }
2903 } else {
2904 if (!too_many_traps(Deoptimization::Reason_null_assert)) {
2905 Node* exact_obj = null_assert(obj);
2906 replace_in_map(obj, exact_obj);
2907 obj = exact_obj;
2908 }
2909 }
2910 return obj;
2911 }
2912
2913 //-------------------------------gen_instanceof--------------------------------
2914 // Generate an instance-of idiom. Used by both the instance-of bytecode
2915 // and the reflective instance-of call.
2916 Node* GraphKit::gen_instanceof(Node* obj, Node* superklass, bool safe_for_replace) {
2917 kill_dead_locals(); // Benefit all the uncommon traps
2918 assert( !stopped(), "dead parse path should be checked in callers" );
2919 assert(!TypePtr::NULL_PTR->higher_equal(_gvn.type(superklass)->is_klassptr()),
2920 "must check for not-null not-dead klass in callers");
2921
2922 // Make the merge point
2923 enum { _obj_path = 1, _fail_path, _null_path, PATH_LIMIT };
2924 RegionNode* region = new RegionNode(PATH_LIMIT);
2925 Node* phi = new PhiNode(region, TypeInt::BOOL);
2926 C->set_has_split_ifs(true); // Has chance for split-if optimization
2927
2928 ciProfileData* data = NULL;
2929 if (java_bc() == Bytecodes::_instanceof) { // Only for the bytecode
2930 data = method()->method_data()->bci_to_data(bci());
2931 }
2932 bool speculative_not_null = false;
2933 bool never_see_null = (ProfileDynamicTypes // aggressive use of profile
2934 && seems_never_null(obj, data, speculative_not_null));
2935
2936 // Null check; get casted pointer; set region slot 3
2937 Node* null_ctl = top();
2938 Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace, speculative_not_null);
2939
2940 // If not_null_obj is dead, only null-path is taken
2941 if (stopped()) { // Doing instance-of on a NULL?
2942 set_control(null_ctl);
2943 return intcon(0);
2944 }
2945 region->init_req(_null_path, null_ctl);
2946 phi ->init_req(_null_path, intcon(0)); // Set null path value
2947 if (null_ctl == top()) {
2948 // Do this eagerly, so that pattern matches like is_diamond_phi
2949 // will work even during parsing.
2950 assert(_null_path == PATH_LIMIT-1, "delete last");
2951 region->del_req(_null_path);
2952 phi ->del_req(_null_path);
2953 }
2954
2955 // Do we know the type check always succeed?
2956 bool known_statically = false;
2957 if (_gvn.type(superklass)->singleton()) {
2958 ciKlass* superk = _gvn.type(superklass)->is_klassptr()->klass();
2959 ciKlass* subk = _gvn.type(obj)->is_oopptr()->klass();
2960 if (subk != NULL && subk->is_loaded()) {
2961 int static_res = static_subtype_check(superk, subk);
2962 known_statically = (static_res == SSC_always_true || static_res == SSC_always_false);
2963 }
2964 }
2965
2966 if (known_statically && UseTypeSpeculation) {
2967 // If we know the type check always succeeds then we don't use the
2968 // profiling data at this bytecode. Don't lose it, feed it to the
2969 // type system as a speculative type.
2970 not_null_obj = record_profiled_receiver_for_speculation(not_null_obj);
2971 } else {
2972 const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
2973 // We may not have profiling here or it may not help us. If we
2974 // have a speculative type use it to perform an exact cast.
2975 ciKlass* spec_obj_type = obj_type->speculative_type();
2976 if (spec_obj_type != NULL || (ProfileDynamicTypes && data != NULL)) {
2977 Node* cast_obj = maybe_cast_profiled_receiver(not_null_obj, NULL, spec_obj_type, safe_for_replace);
2978 if (stopped()) { // Profile disagrees with this path.
2979 set_control(null_ctl); // Null is the only remaining possibility.
2980 return intcon(0);
2981 }
2982 if (cast_obj != NULL) {
2983 not_null_obj = cast_obj;
2984 }
2985 }
2986 }
2987
2988 // Load the object's klass
2989 Node* obj_klass = load_object_klass(not_null_obj);
2990
2991 // Generate the subtype check
2992 Node* not_subtype_ctrl = gen_subtype_check(obj_klass, superklass);
2993
2994 // Plug in the success path to the general merge in slot 1.
2995 region->init_req(_obj_path, control());
2996 phi ->init_req(_obj_path, intcon(1));
2997
2998 // Plug in the failing path to the general merge in slot 2.
2999 region->init_req(_fail_path, not_subtype_ctrl);
3000 phi ->init_req(_fail_path, intcon(0));
3001
3002 // Return final merged results
3003 set_control( _gvn.transform(region) );
3004 record_for_igvn(region);
3005 return _gvn.transform(phi);
3006 }
3007
3008 //-------------------------------gen_checkcast---------------------------------
3009 // Generate a checkcast idiom. Used by both the checkcast bytecode and the
3010 // array store bytecode. Stack must be as-if BEFORE doing the bytecode so the
3011 // uncommon-trap paths work. Adjust stack after this call.
3012 // If failure_control is supplied and not null, it is filled in with
3013 // the control edge for the cast failure. Otherwise, an appropriate
3014 // uncommon trap or exception is thrown.
3015 Node* GraphKit::gen_checkcast(Node *obj, Node* superklass,
3016 Node* *failure_control) {
3017 kill_dead_locals(); // Benefit all the uncommon traps
3018 const TypeKlassPtr *tk = _gvn.type(superklass)->is_klassptr();
3019 const Type *toop = TypeOopPtr::make_from_klass(tk->klass());
3020
3021 // Fast cutout: Check the case that the cast is vacuously true.
3022 // This detects the common cases where the test will short-circuit
3023 // away completely. We do this before we perform the null check,
3024 // because if the test is going to turn into zero code, we don't
3025 // want a residual null check left around. (Causes a slowdown,
3026 // for example, in some objArray manipulations, such as a[i]=a[j].)
3027 if (tk->singleton()) {
3028 const TypeOopPtr* objtp = _gvn.type(obj)->isa_oopptr();
3029 if (objtp != NULL && objtp->klass() != NULL) {
3030 switch (static_subtype_check(tk->klass(), objtp->klass())) {
3031 case SSC_always_true:
3032 // If we know the type check always succeed then we don't use
3033 // the profiling data at this bytecode. Don't lose it, feed it
3034 // to the type system as a speculative type.
3035 return record_profiled_receiver_for_speculation(obj);
3036 case SSC_always_false:
3037 // It needs a null check because a null will *pass* the cast check.
3038 // A non-null value will always produce an exception.
3039 return null_assert(obj);
3040 }
3041 }
3042 }
3043
3044 ciProfileData* data = NULL;
3045 bool safe_for_replace = false;
3046 if (failure_control == NULL) { // use MDO in regular case only
3047 assert(java_bc() == Bytecodes::_aastore ||
3048 java_bc() == Bytecodes::_checkcast,
3049 "interpreter profiles type checks only for these BCs");
3050 data = method()->method_data()->bci_to_data(bci());
3051 safe_for_replace = true;
3052 }
3053
3054 // Make the merge point
3055 enum { _obj_path = 1, _null_path, PATH_LIMIT };
3056 RegionNode* region = new RegionNode(PATH_LIMIT);
3057 Node* phi = new PhiNode(region, toop);
3058 C->set_has_split_ifs(true); // Has chance for split-if optimization
3059
3060 // Use null-cast information if it is available
3061 bool speculative_not_null = false;
3062 bool never_see_null = ((failure_control == NULL) // regular case only
3063 && seems_never_null(obj, data, speculative_not_null));
3064
3065 // Null check; get casted pointer; set region slot 3
3066 Node* null_ctl = top();
3067 Node* not_null_obj = null_check_oop(obj, &null_ctl, never_see_null, safe_for_replace, speculative_not_null);
3068
3069 // If not_null_obj is dead, only null-path is taken
3070 if (stopped()) { // Doing instance-of on a NULL?
3071 set_control(null_ctl);
3072 return null();
3073 }
3074 region->init_req(_null_path, null_ctl);
3075 phi ->init_req(_null_path, null()); // Set null path value
3076 if (null_ctl == top()) {
3077 // Do this eagerly, so that pattern matches like is_diamond_phi
3078 // will work even during parsing.
3079 assert(_null_path == PATH_LIMIT-1, "delete last");
3080 region->del_req(_null_path);
3081 phi ->del_req(_null_path);
3082 }
3083
3084 Node* cast_obj = NULL;
3085 if (tk->klass_is_exact()) {
3086 // The following optimization tries to statically cast the speculative type of the object
3087 // (for example obtained during profiling) to the type of the superklass and then do a
3088 // dynamic check that the type of the object is what we expect. To work correctly
3089 // for checkcast and aastore the type of superklass should be exact.
3090 const TypeOopPtr* obj_type = _gvn.type(obj)->is_oopptr();
3091 // We may not have profiling here or it may not help us. If we have
3092 // a speculative type use it to perform an exact cast.
3093 ciKlass* spec_obj_type = obj_type->speculative_type();
3094 if (spec_obj_type != NULL ||
3095 (data != NULL &&
3096 // Counter has never been decremented (due to cast failure).
3097 // ...This is a reasonable thing to expect. It is true of
3098 // all casts inserted by javac to implement generic types.
3099 data->as_CounterData()->count() >= 0)) {
3100 cast_obj = maybe_cast_profiled_receiver(not_null_obj, tk->klass(), spec_obj_type, safe_for_replace);
3101 if (cast_obj != NULL) {
3102 if (failure_control != NULL) // failure is now impossible
3103 (*failure_control) = top();
3104 // adjust the type of the phi to the exact klass:
3105 phi->raise_bottom_type(_gvn.type(cast_obj)->meet_speculative(TypePtr::NULL_PTR));
3106 }
3107 }
3108 }
3109
3110 if (cast_obj == NULL) {
3111 // Load the object's klass
3112 Node* obj_klass = load_object_klass(not_null_obj);
3113
3114 // Generate the subtype check
3115 Node* not_subtype_ctrl = gen_subtype_check( obj_klass, superklass );
3116
3117 // Plug in success path into the merge
3118 cast_obj = _gvn.transform(new CheckCastPPNode(control(), not_null_obj, toop));
3119 // Failure path ends in uncommon trap (or may be dead - failure impossible)
3120 if (failure_control == NULL) {
3121 if (not_subtype_ctrl != top()) { // If failure is possible
3122 PreserveJVMState pjvms(this);
3123 set_control(not_subtype_ctrl);
3124 builtin_throw(Deoptimization::Reason_class_check, obj_klass);
3125 }
3126 } else {
3127 (*failure_control) = not_subtype_ctrl;
3128 }
3129 }
3130
3131 region->init_req(_obj_path, control());
3132 phi ->init_req(_obj_path, cast_obj);
3133
3134 // A merge of NULL or Casted-NotNull obj
3135 Node* res = _gvn.transform(phi);
3136
3137 // Note I do NOT always 'replace_in_map(obj,result)' here.
3138 // if( tk->klass()->can_be_primary_super() )
3139 // This means that if I successfully store an Object into an array-of-String
3140 // I 'forget' that the Object is really now known to be a String. I have to
3141 // do this because we don't have true union types for interfaces - if I store
3142 // a Baz into an array-of-Interface and then tell the optimizer it's an
3143 // Interface, I forget that it's also a Baz and cannot do Baz-like field
3144 // references to it. FIX THIS WHEN UNION TYPES APPEAR!
3145 // replace_in_map( obj, res );
3146
3147 // Return final merged results
3148 set_control( _gvn.transform(region) );
3149 record_for_igvn(region);
3150 return res;
3151 }
3152
3153 //------------------------------next_monitor-----------------------------------
3154 // What number should be given to the next monitor?
3155 int GraphKit::next_monitor() {
3156 int current = jvms()->monitor_depth()* C->sync_stack_slots();
3157 int next = current + C->sync_stack_slots();
3158 // Keep the toplevel high water mark current:
3159 if (C->fixed_slots() < next) C->set_fixed_slots(next);
3160 return current;
3161 }
3162
3163 //------------------------------insert_mem_bar---------------------------------
3164 // Memory barrier to avoid floating things around
3165 // The membar serves as a pinch point between both control and all memory slices.
3166 Node* GraphKit::insert_mem_bar(int opcode, Node* precedent) {
3167 MemBarNode* mb = MemBarNode::make(C, opcode, Compile::AliasIdxBot, precedent);
3168 mb->init_req(TypeFunc::Control, control());
3169 mb->init_req(TypeFunc::Memory, reset_memory());
3170 Node* membar = _gvn.transform(mb);
3171 set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control)));
3172 set_all_memory_call(membar);
3173 return membar;
3174 }
3175
3176 //-------------------------insert_mem_bar_volatile----------------------------
3177 // Memory barrier to avoid floating things around
3178 // The membar serves as a pinch point between both control and memory(alias_idx).
3179 // If you want to make a pinch point on all memory slices, do not use this
3180 // function (even with AliasIdxBot); use insert_mem_bar() instead.
3181 Node* GraphKit::insert_mem_bar_volatile(int opcode, int alias_idx, Node* precedent) {
3182 // When Parse::do_put_xxx updates a volatile field, it appends a series
3183 // of MemBarVolatile nodes, one for *each* volatile field alias category.
3184 // The first membar is on the same memory slice as the field store opcode.
3185 // This forces the membar to follow the store. (Bug 6500685 broke this.)
3186 // All the other membars (for other volatile slices, including AliasIdxBot,
3187 // which stands for all unknown volatile slices) are control-dependent
3188 // on the first membar. This prevents later volatile loads or stores
3189 // from sliding up past the just-emitted store.
3190
3191 MemBarNode* mb = MemBarNode::make(C, opcode, alias_idx, precedent);
3192 mb->set_req(TypeFunc::Control,control());
3193 if (alias_idx == Compile::AliasIdxBot) {
3194 mb->set_req(TypeFunc::Memory, merged_memory()->base_memory());
3195 } else {
3196 assert(!(opcode == Op_Initialize && alias_idx != Compile::AliasIdxRaw), "fix caller");
3197 mb->set_req(TypeFunc::Memory, memory(alias_idx));
3198 }
3199 Node* membar = _gvn.transform(mb);
3200 set_control(_gvn.transform(new ProjNode(membar, TypeFunc::Control)));
3201 if (alias_idx == Compile::AliasIdxBot) {
3202 merged_memory()->set_base_memory(_gvn.transform(new ProjNode(membar, TypeFunc::Memory)));
3203 } else {
3204 set_memory(_gvn.transform(new ProjNode(membar, TypeFunc::Memory)),alias_idx);
3205 }
3206 return membar;
3207 }
3208
3209 //------------------------------shared_lock------------------------------------
3210 // Emit locking code.
3211 FastLockNode* GraphKit::shared_lock(Node* obj) {
3212 // bci is either a monitorenter bc or InvocationEntryBci
3213 // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3214 assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3215
3216 if( !GenerateSynchronizationCode )
3217 return NULL; // Not locking things?
3218 if (stopped()) // Dead monitor?
3219 return NULL;
3220
3221 assert(dead_locals_are_killed(), "should kill locals before sync. point");
3222
3223 // Box the stack location
3224 Node* box = _gvn.transform(new BoxLockNode(next_monitor()));
3225 Node* mem = reset_memory();
3226
3227 FastLockNode * flock = _gvn.transform(new FastLockNode(0, obj, box) )->as_FastLock();
3228 if (UseBiasedLocking && PrintPreciseBiasedLockingStatistics) {
3229 // Create the counters for this fast lock.
3230 flock->create_lock_counter(sync_jvms()); // sync_jvms used to get current bci
3231 }
3232
3233 // Create the rtm counters for this fast lock if needed.
3234 flock->create_rtm_lock_counter(sync_jvms()); // sync_jvms used to get current bci
3235
3236 // Add monitor to debug info for the slow path. If we block inside the
3237 // slow path and de-opt, we need the monitor hanging around
3238 map()->push_monitor( flock );
3239
3240 const TypeFunc *tf = LockNode::lock_type();
3241 LockNode *lock = new LockNode(C, tf);
3242
3243 lock->init_req( TypeFunc::Control, control() );
3244 lock->init_req( TypeFunc::Memory , mem );
3245 lock->init_req( TypeFunc::I_O , top() ) ; // does no i/o
3246 lock->init_req( TypeFunc::FramePtr, frameptr() );
3247 lock->init_req( TypeFunc::ReturnAdr, top() );
3248
3249 lock->init_req(TypeFunc::Parms + 0, obj);
3250 lock->init_req(TypeFunc::Parms + 1, box);
3251 lock->init_req(TypeFunc::Parms + 2, flock);
3252 add_safepoint_edges(lock);
3253
3254 lock = _gvn.transform( lock )->as_Lock();
3255
3256 // lock has no side-effects, sets few values
3257 set_predefined_output_for_runtime_call(lock, mem, TypeRawPtr::BOTTOM);
3258
3259 insert_mem_bar(Op_MemBarAcquireLock);
3260
3261 // Add this to the worklist so that the lock can be eliminated
3262 record_for_igvn(lock);
3263
3264 #ifndef PRODUCT
3265 if (PrintLockStatistics) {
3266 // Update the counter for this lock. Don't bother using an atomic
3267 // operation since we don't require absolute accuracy.
3268 lock->create_lock_counter(map()->jvms());
3269 increment_counter(lock->counter()->addr());
3270 }
3271 #endif
3272
3273 return flock;
3274 }
3275
3276
3277 //------------------------------shared_unlock----------------------------------
3278 // Emit unlocking code.
3279 void GraphKit::shared_unlock(Node* box, Node* obj) {
3280 // bci is either a monitorenter bc or InvocationEntryBci
3281 // %%% SynchronizationEntryBCI is redundant; use InvocationEntryBci in interfaces
3282 assert(SynchronizationEntryBCI == InvocationEntryBci, "");
3283
3284 if( !GenerateSynchronizationCode )
3285 return;
3286 if (stopped()) { // Dead monitor?
3287 map()->pop_monitor(); // Kill monitor from debug info
3288 return;
3289 }
3290
3291 // Memory barrier to avoid floating things down past the locked region
3292 insert_mem_bar(Op_MemBarReleaseLock);
3293
3294 const TypeFunc *tf = OptoRuntime::complete_monitor_exit_Type();
3295 UnlockNode *unlock = new UnlockNode(C, tf);
3296 uint raw_idx = Compile::AliasIdxRaw;
3297 unlock->init_req( TypeFunc::Control, control() );
3298 unlock->init_req( TypeFunc::Memory , memory(raw_idx) );
3299 unlock->init_req( TypeFunc::I_O , top() ) ; // does no i/o
3300 unlock->init_req( TypeFunc::FramePtr, frameptr() );
3301 unlock->init_req( TypeFunc::ReturnAdr, top() );
3302
3303 unlock->init_req(TypeFunc::Parms + 0, obj);
3304 unlock->init_req(TypeFunc::Parms + 1, box);
3305 unlock = _gvn.transform(unlock)->as_Unlock();
3306
3307 Node* mem = reset_memory();
3308
3309 // unlock has no side-effects, sets few values
3310 set_predefined_output_for_runtime_call(unlock, mem, TypeRawPtr::BOTTOM);
3311
3312 // Kill monitor from debug info
3313 map()->pop_monitor( );
3314 }
3315
3316 //-------------------------------get_layout_helper-----------------------------
3317 // If the given klass is a constant or known to be an array,
3318 // fetch the constant layout helper value into constant_value
3319 // and return (Node*)NULL. Otherwise, load the non-constant
3320 // layout helper value, and return the node which represents it.
3321 // This two-faced routine is useful because allocation sites
3322 // almost always feature constant types.
3323 Node* GraphKit::get_layout_helper(Node* klass_node, jint& constant_value) {
3324 const TypeKlassPtr* inst_klass = _gvn.type(klass_node)->isa_klassptr();
3325 if (!StressReflectiveCode && inst_klass != NULL) {
3326 ciKlass* klass = inst_klass->klass();
3327 bool xklass = inst_klass->klass_is_exact();
3328 if (xklass || klass->is_array_klass()) {
3329 jint lhelper = klass->layout_helper();
3330 if (lhelper != Klass::_lh_neutral_value) {
3331 constant_value = lhelper;
3332 return (Node*) NULL;
3333 }
3334 }
3335 }
3336 constant_value = Klass::_lh_neutral_value; // put in a known value
3337 Node* lhp = basic_plus_adr(klass_node, klass_node, in_bytes(Klass::layout_helper_offset()));
3338 return make_load(NULL, lhp, TypeInt::INT, T_INT, MemNode::unordered);
3339 }
3340
3341 // We just put in an allocate/initialize with a big raw-memory effect.
3342 // Hook selected additional alias categories on the initialization.
3343 static void hook_memory_on_init(GraphKit& kit, int alias_idx,
3344 MergeMemNode* init_in_merge,
3345 Node* init_out_raw) {
3346 DEBUG_ONLY(Node* init_in_raw = init_in_merge->base_memory());
3347 assert(init_in_merge->memory_at(alias_idx) == init_in_raw, "");
3348
3349 Node* prevmem = kit.memory(alias_idx);
3350 init_in_merge->set_memory_at(alias_idx, prevmem);
3351 kit.set_memory(init_out_raw, alias_idx);
3352 }
3353
3354 //---------------------------set_output_for_allocation-------------------------
3355 Node* GraphKit::set_output_for_allocation(AllocateNode* alloc,
3356 const TypeOopPtr* oop_type) {
3357 int rawidx = Compile::AliasIdxRaw;
3358 alloc->set_req( TypeFunc::FramePtr, frameptr() );
3359 add_safepoint_edges(alloc);
3360 Node* allocx = _gvn.transform(alloc);
3361 set_control( _gvn.transform(new ProjNode(allocx, TypeFunc::Control) ) );
3362 // create memory projection for i_o
3363 set_memory ( _gvn.transform( new ProjNode(allocx, TypeFunc::Memory, true) ), rawidx );
3364 make_slow_call_ex(allocx, env()->Throwable_klass(), true);
3365
3366 // create a memory projection as for the normal control path
3367 Node* malloc = _gvn.transform(new ProjNode(allocx, TypeFunc::Memory));
3368 set_memory(malloc, rawidx);
3369
3370 // a normal slow-call doesn't change i_o, but an allocation does
3371 // we create a separate i_o projection for the normal control path
3372 set_i_o(_gvn.transform( new ProjNode(allocx, TypeFunc::I_O, false) ) );
3373 Node* rawoop = _gvn.transform( new ProjNode(allocx, TypeFunc::Parms) );
3374
3375 // put in an initialization barrier
3376 InitializeNode* init = insert_mem_bar_volatile(Op_Initialize, rawidx,
3377 rawoop)->as_Initialize();
3378 assert(alloc->initialization() == init, "2-way macro link must work");
3379 assert(init ->allocation() == alloc, "2-way macro link must work");
3380 {
3381 // Extract memory strands which may participate in the new object's
3382 // initialization, and source them from the new InitializeNode.
3383 // This will allow us to observe initializations when they occur,
3384 // and link them properly (as a group) to the InitializeNode.
3385 assert(init->in(InitializeNode::Memory) == malloc, "");
3386 MergeMemNode* minit_in = MergeMemNode::make(C, malloc);
3387 init->set_req(InitializeNode::Memory, minit_in);
3388 record_for_igvn(minit_in); // fold it up later, if possible
3389 Node* minit_out = memory(rawidx);
3390 assert(minit_out->is_Proj() && minit_out->in(0) == init, "");
3391 if (oop_type->isa_aryptr()) {
3392 const TypePtr* telemref = oop_type->add_offset(Type::OffsetBot);
3393 int elemidx = C->get_alias_index(telemref);
3394 hook_memory_on_init(*this, elemidx, minit_in, minit_out);
3395 } else if (oop_type->isa_instptr()) {
3396 ciInstanceKlass* ik = oop_type->klass()->as_instance_klass();
3397 for (int i = 0, len = ik->nof_nonstatic_fields(); i < len; i++) {
3398 ciField* field = ik->nonstatic_field_at(i);
3399 if (field->offset() >= TrackedInitializationLimit * HeapWordSize)
3400 continue; // do not bother to track really large numbers of fields
3401 // Find (or create) the alias category for this field:
3402 int fieldidx = C->alias_type(field)->index();
3403 hook_memory_on_init(*this, fieldidx, minit_in, minit_out);
3404 }
3405 }
3406 }
3407
3408 // Cast raw oop to the real thing...
3409 Node* javaoop = new CheckCastPPNode(control(), rawoop, oop_type);
3410 javaoop = _gvn.transform(javaoop);
3411 C->set_recent_alloc(control(), javaoop);
3412 assert(just_allocated_object(control()) == javaoop, "just allocated");
3413
3414 #ifdef ASSERT
3415 { // Verify that the AllocateNode::Ideal_allocation recognizers work:
3416 assert(AllocateNode::Ideal_allocation(rawoop, &_gvn) == alloc,
3417 "Ideal_allocation works");
3418 assert(AllocateNode::Ideal_allocation(javaoop, &_gvn) == alloc,
3419 "Ideal_allocation works");
3420 if (alloc->is_AllocateArray()) {
3421 assert(AllocateArrayNode::Ideal_array_allocation(rawoop, &_gvn) == alloc->as_AllocateArray(),
3422 "Ideal_allocation works");
3423 assert(AllocateArrayNode::Ideal_array_allocation(javaoop, &_gvn) == alloc->as_AllocateArray(),
3424 "Ideal_allocation works");
3425 } else {
3426 assert(alloc->in(AllocateNode::ALength)->is_top(), "no length, please");
3427 }
3428 }
3429 #endif //ASSERT
3430
3431 return javaoop;
3432 }
3433
3434 //---------------------------new_instance--------------------------------------
3435 // This routine takes a klass_node which may be constant (for a static type)
3436 // or may be non-constant (for reflective code). It will work equally well
3437 // for either, and the graph will fold nicely if the optimizer later reduces
3438 // the type to a constant.
3439 // The optional arguments are for specialized use by intrinsics:
3440 // - If 'extra_slow_test' if not null is an extra condition for the slow-path.
3441 // - If 'return_size_val', report the the total object size to the caller.
3442 Node* GraphKit::new_instance(Node* klass_node,
3443 Node* extra_slow_test,
3444 Node* *return_size_val) {
3445 // Compute size in doublewords
3446 // The size is always an integral number of doublewords, represented
3447 // as a positive bytewise size stored in the klass's layout_helper.
3448 // The layout_helper also encodes (in a low bit) the need for a slow path.
3449 jint layout_con = Klass::_lh_neutral_value;
3450 Node* layout_val = get_layout_helper(klass_node, layout_con);
3451 int layout_is_con = (layout_val == NULL);
3452
3453 if (extra_slow_test == NULL) extra_slow_test = intcon(0);
3454 // Generate the initial go-slow test. It's either ALWAYS (return a
3455 // Node for 1) or NEVER (return a NULL) or perhaps (in the reflective
3456 // case) a computed value derived from the layout_helper.
3457 Node* initial_slow_test = NULL;
3458 if (layout_is_con) {
3459 assert(!StressReflectiveCode, "stress mode does not use these paths");
3460 bool must_go_slow = Klass::layout_helper_needs_slow_path(layout_con);
3461 initial_slow_test = must_go_slow? intcon(1): extra_slow_test;
3462
3463 } else { // reflective case
3464 // This reflective path is used by Unsafe.allocateInstance.
3465 // (It may be stress-tested by specifying StressReflectiveCode.)
3466 // Basically, we want to get into the VM is there's an illegal argument.
3467 Node* bit = intcon(Klass::_lh_instance_slow_path_bit);
3468 initial_slow_test = _gvn.transform( new AndINode(layout_val, bit) );
3469 if (extra_slow_test != intcon(0)) {
3470 initial_slow_test = _gvn.transform( new OrINode(initial_slow_test, extra_slow_test) );
3471 }
3472 // (Macro-expander will further convert this to a Bool, if necessary.)
3473 }
3474
3475 // Find the size in bytes. This is easy; it's the layout_helper.
3476 // The size value must be valid even if the slow path is taken.
3477 Node* size = NULL;
3478 if (layout_is_con) {
3479 size = MakeConX(Klass::layout_helper_size_in_bytes(layout_con));
3480 } else { // reflective case
3481 // This reflective path is used by clone and Unsafe.allocateInstance.
3482 size = ConvI2X(layout_val);
3483
3484 // Clear the low bits to extract layout_helper_size_in_bytes:
3485 assert((int)Klass::_lh_instance_slow_path_bit < BytesPerLong, "clear bit");
3486 Node* mask = MakeConX(~ (intptr_t)right_n_bits(LogBytesPerLong));
3487 size = _gvn.transform( new AndXNode(size, mask) );
3488 }
3489 if (return_size_val != NULL) {
3490 (*return_size_val) = size;
3491 }
3492
3493 // This is a precise notnull oop of the klass.
3494 // (Actually, it need not be precise if this is a reflective allocation.)
3495 // It's what we cast the result to.
3496 const TypeKlassPtr* tklass = _gvn.type(klass_node)->isa_klassptr();
3497 if (!tklass) tklass = TypeKlassPtr::OBJECT;
3498 const TypeOopPtr* oop_type = tklass->as_instance_type();
3499
3500 // Now generate allocation code
3501
3502 // The entire memory state is needed for slow path of the allocation
3503 // since GC and deoptimization can happened.
3504 Node *mem = reset_memory();
3505 set_all_memory(mem); // Create new memory state
3506
3507 AllocateNode* alloc = new AllocateNode(C, AllocateNode::alloc_type(Type::TOP),
3508 control(), mem, i_o(),
3509 size, klass_node,
3510 initial_slow_test);
3511
3512 return set_output_for_allocation(alloc, oop_type);
3513 }
3514
3515 //-------------------------------new_array-------------------------------------
3516 // helper for both newarray and anewarray
3517 // The 'length' parameter is (obviously) the length of the array.
3518 // See comments on new_instance for the meaning of the other arguments.
3519 Node* GraphKit::new_array(Node* klass_node, // array klass (maybe variable)
3520 Node* length, // number of array elements
3521 int nargs, // number of arguments to push back for uncommon trap
3522 Node* *return_size_val) {
3523 jint layout_con = Klass::_lh_neutral_value;
3524 Node* layout_val = get_layout_helper(klass_node, layout_con);
3525 int layout_is_con = (layout_val == NULL);
3526
3527 if (!layout_is_con && !StressReflectiveCode &&
3528 !too_many_traps(Deoptimization::Reason_class_check)) {
3529 // This is a reflective array creation site.
3530 // Optimistically assume that it is a subtype of Object[],
3531 // so that we can fold up all the address arithmetic.
3532 layout_con = Klass::array_layout_helper(T_OBJECT);
3533 Node* cmp_lh = _gvn.transform( new CmpINode(layout_val, intcon(layout_con)) );
3534 Node* bol_lh = _gvn.transform( new BoolNode(cmp_lh, BoolTest::eq) );
3535 { BuildCutout unless(this, bol_lh, PROB_MAX);
3536 inc_sp(nargs);
3537 uncommon_trap(Deoptimization::Reason_class_check,
3538 Deoptimization::Action_maybe_recompile);
3539 }
3540 layout_val = NULL;
3541 layout_is_con = true;
3542 }
3543
3544 // Generate the initial go-slow test. Make sure we do not overflow
3545 // if length is huge (near 2Gig) or negative! We do not need
3546 // exact double-words here, just a close approximation of needed
3547 // double-words. We can't add any offset or rounding bits, lest we
3548 // take a size -1 of bytes and make it positive. Use an unsigned
3549 // compare, so negative sizes look hugely positive.
3550 int fast_size_limit = FastAllocateSizeLimit;
3551 if (layout_is_con) {
3552 assert(!StressReflectiveCode, "stress mode does not use these paths");
3553 // Increase the size limit if we have exact knowledge of array type.
3554 int log2_esize = Klass::layout_helper_log2_element_size(layout_con);
3555 fast_size_limit <<= (LogBytesPerLong - log2_esize);
3556 }
3557
3558 Node* initial_slow_cmp = _gvn.transform( new CmpUNode( length, intcon( fast_size_limit ) ) );
3559 Node* initial_slow_test = _gvn.transform( new BoolNode( initial_slow_cmp, BoolTest::gt ) );
3560 if (initial_slow_test->is_Bool()) {
3561 // Hide it behind a CMoveI, or else PhaseIdealLoop::split_up will get sick.
3562 initial_slow_test = initial_slow_test->as_Bool()->as_int_value(&_gvn);
3563 }
3564
3565 // --- Size Computation ---
3566 // array_size = round_to_heap(array_header + (length << elem_shift));
3567 // where round_to_heap(x) == round_to(x, MinObjAlignmentInBytes)
3568 // and round_to(x, y) == ((x + y-1) & ~(y-1))
3569 // The rounding mask is strength-reduced, if possible.
3570 int round_mask = MinObjAlignmentInBytes - 1;
3571 Node* header_size = NULL;
3572 int header_size_min = arrayOopDesc::base_offset_in_bytes(T_BYTE);
3573 // (T_BYTE has the weakest alignment and size restrictions...)
3574 if (layout_is_con) {
3575 int hsize = Klass::layout_helper_header_size(layout_con);
3576 int eshift = Klass::layout_helper_log2_element_size(layout_con);
3577 BasicType etype = Klass::layout_helper_element_type(layout_con);
3578 if ((round_mask & ~right_n_bits(eshift)) == 0)
3579 round_mask = 0; // strength-reduce it if it goes away completely
3580 assert((hsize & right_n_bits(eshift)) == 0, "hsize is pre-rounded");
3581 assert(header_size_min <= hsize, "generic minimum is smallest");
3582 header_size_min = hsize;
3583 header_size = intcon(hsize + round_mask);
3584 } else {
3585 Node* hss = intcon(Klass::_lh_header_size_shift);
3586 Node* hsm = intcon(Klass::_lh_header_size_mask);
3587 Node* hsize = _gvn.transform( new URShiftINode(layout_val, hss) );
3588 hsize = _gvn.transform( new AndINode(hsize, hsm) );
3589 Node* mask = intcon(round_mask);
3590 header_size = _gvn.transform( new AddINode(hsize, mask) );
3591 }
3592
3593 Node* elem_shift = NULL;
3594 if (layout_is_con) {
3595 int eshift = Klass::layout_helper_log2_element_size(layout_con);
3596 if (eshift != 0)
3597 elem_shift = intcon(eshift);
3598 } else {
3599 // There is no need to mask or shift this value.
3600 // The semantics of LShiftINode include an implicit mask to 0x1F.
3601 assert(Klass::_lh_log2_element_size_shift == 0, "use shift in place");
3602 elem_shift = layout_val;
3603 }
3604
3605 // Transition to native address size for all offset calculations:
3606 Node* lengthx = ConvI2X(length);
3607 Node* headerx = ConvI2X(header_size);
3608 #ifdef _LP64
3609 { const TypeLong* tllen = _gvn.find_long_type(lengthx);
3610 if (tllen != NULL && tllen->_lo < 0) {
3611 // Add a manual constraint to a positive range. Cf. array_element_address.
3612 jlong size_max = arrayOopDesc::max_array_length(T_BYTE);
3613 if (size_max > tllen->_hi) size_max = tllen->_hi;
3614 const TypeLong* tlcon = TypeLong::make(CONST64(0), size_max, Type::WidenMin);
3615 lengthx = _gvn.transform( new ConvI2LNode(length, tlcon));
3616 }
3617 }
3618 #endif
3619
3620 // Combine header size (plus rounding) and body size. Then round down.
3621 // This computation cannot overflow, because it is used only in two
3622 // places, one where the length is sharply limited, and the other
3623 // after a successful allocation.
3624 Node* abody = lengthx;
3625 if (elem_shift != NULL)
3626 abody = _gvn.transform( new LShiftXNode(lengthx, elem_shift) );
3627 Node* size = _gvn.transform( new AddXNode(headerx, abody) );
3628 if (round_mask != 0) {
3629 Node* mask = MakeConX(~round_mask);
3630 size = _gvn.transform( new AndXNode(size, mask) );
3631 }
3632 // else if round_mask == 0, the size computation is self-rounding
3633
3634 if (return_size_val != NULL) {
3635 // This is the size
3636 (*return_size_val) = size;
3637 }
3638
3639 // Now generate allocation code
3640
3641 // The entire memory state is needed for slow path of the allocation
3642 // since GC and deoptimization can happened.
3643 Node *mem = reset_memory();
3644 set_all_memory(mem); // Create new memory state
3645
3646 // Create the AllocateArrayNode and its result projections
3647 AllocateArrayNode* alloc
3648 = new AllocateArrayNode(C, AllocateArrayNode::alloc_type(TypeInt::INT),
3649 control(), mem, i_o(),
3650 size, klass_node,
3651 initial_slow_test,
3652 length);
3653
3654 // Cast to correct type. Note that the klass_node may be constant or not,
3655 // and in the latter case the actual array type will be inexact also.
3656 // (This happens via a non-constant argument to inline_native_newArray.)
3657 // In any case, the value of klass_node provides the desired array type.
3658 const TypeInt* length_type = _gvn.find_int_type(length);
3659 const TypeOopPtr* ary_type = _gvn.type(klass_node)->is_klassptr()->as_instance_type();
3660 if (ary_type->isa_aryptr() && length_type != NULL) {
3661 // Try to get a better type than POS for the size
3662 ary_type = ary_type->is_aryptr()->cast_to_size(length_type);
3663 }
3664
3665 Node* javaoop = set_output_for_allocation(alloc, ary_type);
3666
3667 // Cast length on remaining path to be as narrow as possible
3668 if (map()->find_edge(length) >= 0) {
3669 Node* ccast = alloc->make_ideal_length(ary_type, &_gvn);
3670 if (ccast != length) {
3671 _gvn.set_type_bottom(ccast);
3672 record_for_igvn(ccast);
3673 replace_in_map(length, ccast);
3674 }
3675 }
3676
3677 return javaoop;
3678 }
3679
3680 // The following "Ideal_foo" functions are placed here because they recognize
3681 // the graph shapes created by the functions immediately above.
3682
3683 //---------------------------Ideal_allocation----------------------------------
3684 // Given an oop pointer or raw pointer, see if it feeds from an AllocateNode.
3685 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase) {
3686 if (ptr == NULL) { // reduce dumb test in callers
3687 return NULL;
3688 }
3689 if (ptr->is_CheckCastPP()) { // strip only one raw-to-oop cast
3690 ptr = ptr->in(1);
3691 if (ptr == NULL) return NULL;
3692 }
3693 // Return NULL for allocations with several casts:
3694 // j.l.reflect.Array.newInstance(jobject, jint)
3695 // Object.clone()
3696 // to keep more precise type from last cast.
3697 if (ptr->is_Proj()) {
3698 Node* allo = ptr->in(0);
3699 if (allo != NULL && allo->is_Allocate()) {
3700 return allo->as_Allocate();
3701 }
3702 }
3703 // Report failure to match.
3704 return NULL;
3705 }
3706
3707 // Fancy version which also strips off an offset (and reports it to caller).
3708 AllocateNode* AllocateNode::Ideal_allocation(Node* ptr, PhaseTransform* phase,
3709 intptr_t& offset) {
3710 Node* base = AddPNode::Ideal_base_and_offset(ptr, phase, offset);
3711 if (base == NULL) return NULL;
3712 return Ideal_allocation(base, phase);
3713 }
3714
3715 // Trace Initialize <- Proj[Parm] <- Allocate
3716 AllocateNode* InitializeNode::allocation() {
3717 Node* rawoop = in(InitializeNode::RawAddress);
3718 if (rawoop->is_Proj()) {
3719 Node* alloc = rawoop->in(0);
3720 if (alloc->is_Allocate()) {
3721 return alloc->as_Allocate();
3722 }
3723 }
3724 return NULL;
3725 }
3726
3727 // Trace Allocate -> Proj[Parm] -> Initialize
3728 InitializeNode* AllocateNode::initialization() {
3729 ProjNode* rawoop = proj_out(AllocateNode::RawAddress);
3730 if (rawoop == NULL) return NULL;
3731 for (DUIterator_Fast imax, i = rawoop->fast_outs(imax); i < imax; i++) {
3732 Node* init = rawoop->fast_out(i);
3733 if (init->is_Initialize()) {
3734 assert(init->as_Initialize()->allocation() == this, "2-way link");
3735 return init->as_Initialize();
3736 }
3737 }
3738 return NULL;
3739 }
3740
3741 //----------------------------- loop predicates ---------------------------
3742
3743 //------------------------------add_predicate_impl----------------------------
3744 void GraphKit::add_predicate_impl(Deoptimization::DeoptReason reason, int nargs) {
3745 // Too many traps seen?
3746 if (too_many_traps(reason)) {
3747 #ifdef ASSERT
3748 if (TraceLoopPredicate) {
3749 int tc = C->trap_count(reason);
3750 tty->print("too many traps=%s tcount=%d in ",
3751 Deoptimization::trap_reason_name(reason), tc);
3752 method()->print(); // which method has too many predicate traps
3753 tty->cr();
3754 }
3755 #endif
3756 // We cannot afford to take more traps here,
3757 // do not generate predicate.
3758 return;
3759 }
3760
3761 Node *cont = _gvn.intcon(1);
3762 Node* opq = _gvn.transform(new Opaque1Node(C, cont));
3763 Node *bol = _gvn.transform(new Conv2BNode(opq));
3764 IfNode* iff = create_and_map_if(control(), bol, PROB_MAX, COUNT_UNKNOWN);
3765 Node* iffalse = _gvn.transform(new IfFalseNode(iff));
3766 C->add_predicate_opaq(opq);
3767 {
3768 PreserveJVMState pjvms(this);
3769 set_control(iffalse);
3770 inc_sp(nargs);
3771 uncommon_trap(reason, Deoptimization::Action_maybe_recompile);
3772 }
3773 Node* iftrue = _gvn.transform(new IfTrueNode(iff));
3774 set_control(iftrue);
3775 }
3776
3777 //------------------------------add_predicate---------------------------------
3778 void GraphKit::add_predicate(int nargs) {
3779 if (UseLoopPredicate) {
3780 add_predicate_impl(Deoptimization::Reason_predicate, nargs);
3781 }
3782 // loop's limit check predicate should be near the loop.
3783 if (LoopLimitCheck) {
3784 add_predicate_impl(Deoptimization::Reason_loop_limit_check, nargs);
3785 }
3786 }
3787
3788 //----------------------------- store barriers ----------------------------
3789 #define __ ideal.
3790
3791 void GraphKit::sync_kit(IdealKit& ideal) {
3792 set_all_memory(__ merged_memory());
3793 set_i_o(__ i_o());
3794 set_control(__ ctrl());
3795 }
3796
3797 void GraphKit::final_sync(IdealKit& ideal) {
3798 // Final sync IdealKit and graphKit.
3799 sync_kit(ideal);
3800 }
3801
3802 // vanilla/CMS post barrier
3803 // Insert a write-barrier store. This is to let generational GC work; we have
3804 // to flag all oop-stores before the next GC point.
3805 void GraphKit::write_barrier_post(Node* oop_store,
3806 Node* obj,
3807 Node* adr,
3808 uint adr_idx,
3809 Node* val,
3810 bool use_precise) {
3811 // No store check needed if we're storing a NULL or an old object
3812 // (latter case is probably a string constant). The concurrent
3813 // mark sweep garbage collector, however, needs to have all nonNull
3814 // oop updates flagged via card-marks.
3815 if (val != NULL && val->is_Con()) {
3816 // must be either an oop or NULL
3817 const Type* t = val->bottom_type();
3818 if (t == TypePtr::NULL_PTR || t == Type::TOP)
3819 // stores of null never (?) need barriers
3820 return;
3821 }
3822
3823 if (use_ReduceInitialCardMarks()
3824 && obj == just_allocated_object(control())) {
3825 // We can skip marks on a freshly-allocated object in Eden.
3826 // Keep this code in sync with new_store_pre_barrier() in runtime.cpp.
3827 // That routine informs GC to take appropriate compensating steps,
3828 // upon a slow-path allocation, so as to make this card-mark
3829 // elision safe.
3830 return;
3831 }
3832
3833 if (!use_precise) {
3834 // All card marks for a (non-array) instance are in one place:
3835 adr = obj;
3836 }
3837 // (Else it's an array (or unknown), and we want more precise card marks.)
3838 assert(adr != NULL, "");
3839
3840 IdealKit ideal(this, true);
3841
3842 // Convert the pointer to an int prior to doing math on it
3843 Node* cast = __ CastPX(__ ctrl(), adr);
3844
3845 // Divide by card size
3846 assert(Universe::heap()->barrier_set()->kind() == BarrierSet::CardTableModRef,
3847 "Only one we handle so far.");
3848 Node* card_offset = __ URShiftX( cast, __ ConI(CardTableModRefBS::card_shift) );
3849
3850 // Combine card table base and card offset
3851 Node* card_adr = __ AddP(__ top(), byte_map_base_node(), card_offset );
3852
3853 // Get the alias_index for raw card-mark memory
3854 int adr_type = Compile::AliasIdxRaw;
3855 Node* zero = __ ConI(0); // Dirty card value
3856 BasicType bt = T_BYTE;
3857
3858 if (UseCondCardMark) {
3859 // The classic GC reference write barrier is typically implemented
3860 // as a store into the global card mark table. Unfortunately
3861 // unconditional stores can result in false sharing and excessive
3862 // coherence traffic as well as false transactional aborts.
3863 // UseCondCardMark enables MP "polite" conditional card mark
3864 // stores. In theory we could relax the load from ctrl() to
3865 // no_ctrl, but that doesn't buy much latitude.
3866 Node* card_val = __ load( __ ctrl(), card_adr, TypeInt::BYTE, bt, adr_type);
3867 __ if_then(card_val, BoolTest::ne, zero);
3868 }
3869
3870 // Smash zero into card
3871 if( !UseConcMarkSweepGC ) {
3872 __ store(__ ctrl(), card_adr, zero, bt, adr_type, MemNode::release);
3873 } else {
3874 // Specialized path for CM store barrier
3875 __ storeCM(__ ctrl(), card_adr, zero, oop_store, adr_idx, bt, adr_type);
3876 }
3877
3878 if (UseCondCardMark) {
3879 __ end_if();
3880 }
3881
3882 // Final sync IdealKit and GraphKit.
3883 final_sync(ideal);
3884 }
3885
3886 // G1 pre/post barriers
3887 void GraphKit::g1_write_barrier_pre(bool do_load,
3888 Node* obj,
3889 Node* adr,
3890 uint alias_idx,
3891 Node* val,
3892 const TypeOopPtr* val_type,
3893 Node* pre_val,
3894 BasicType bt) {
3895
3896 // Some sanity checks
3897 // Note: val is unused in this routine.
3898
3899 if (do_load) {
3900 // We need to generate the load of the previous value
3901 assert(obj != NULL, "must have a base");
3902 assert(adr != NULL, "where are loading from?");
3903 assert(pre_val == NULL, "loaded already?");
3904 assert(val_type != NULL, "need a type");
3905 } else {
3906 // In this case both val_type and alias_idx are unused.
3907 assert(pre_val != NULL, "must be loaded already");
3908 // Nothing to be done if pre_val is null.
3909 if (pre_val->bottom_type() == TypePtr::NULL_PTR) return;
3910 assert(pre_val->bottom_type()->basic_type() == T_OBJECT, "or we shouldn't be here");
3911 }
3912 assert(bt == T_OBJECT, "or we shouldn't be here");
3913
3914 IdealKit ideal(this, true);
3915
3916 Node* tls = __ thread(); // ThreadLocalStorage
3917
3918 Node* no_ctrl = NULL;
3919 Node* no_base = __ top();
3920 Node* zero = __ ConI(0);
3921 Node* zeroX = __ ConX(0);
3922
3923 float likely = PROB_LIKELY(0.999);
3924 float unlikely = PROB_UNLIKELY(0.999);
3925
3926 BasicType active_type = in_bytes(PtrQueue::byte_width_of_active()) == 4 ? T_INT : T_BYTE;
3927 assert(in_bytes(PtrQueue::byte_width_of_active()) == 4 || in_bytes(PtrQueue::byte_width_of_active()) == 1, "flag width");
3928
3929 // Offsets into the thread
3930 const int marking_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 648
3931 PtrQueue::byte_offset_of_active());
3932 const int index_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 656
3933 PtrQueue::byte_offset_of_index());
3934 const int buffer_offset = in_bytes(JavaThread::satb_mark_queue_offset() + // 652
3935 PtrQueue::byte_offset_of_buf());
3936
3937 // Now the actual pointers into the thread
3938 Node* marking_adr = __ AddP(no_base, tls, __ ConX(marking_offset));
3939 Node* buffer_adr = __ AddP(no_base, tls, __ ConX(buffer_offset));
3940 Node* index_adr = __ AddP(no_base, tls, __ ConX(index_offset));
3941
3942 // Now some of the values
3943 Node* marking = __ load(__ ctrl(), marking_adr, TypeInt::INT, active_type, Compile::AliasIdxRaw);
3944
3945 // if (!marking)
3946 __ if_then(marking, BoolTest::ne, zero, unlikely); {
3947 BasicType index_bt = TypeX_X->basic_type();
3948 assert(sizeof(size_t) == type2aelembytes(index_bt), "Loading G1 PtrQueue::_index with wrong size.");
3949 Node* index = __ load(__ ctrl(), index_adr, TypeX_X, index_bt, Compile::AliasIdxRaw);
3950
3951 if (do_load) {
3952 // load original value
3953 // alias_idx correct??
3954 pre_val = __ load(__ ctrl(), adr, val_type, bt, alias_idx);
3955 }
3956
3957 // if (pre_val != NULL)
3958 __ if_then(pre_val, BoolTest::ne, null()); {
3959 Node* buffer = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw);
3960
3961 // is the queue for this thread full?
3962 __ if_then(index, BoolTest::ne, zeroX, likely); {
3963
3964 // decrement the index
3965 Node* next_index = _gvn.transform(new SubXNode(index, __ ConX(sizeof(intptr_t))));
3966
3967 // Now get the buffer location we will log the previous value into and store it
3968 Node *log_addr = __ AddP(no_base, buffer, next_index);
3969 __ store(__ ctrl(), log_addr, pre_val, T_OBJECT, Compile::AliasIdxRaw, MemNode::unordered);
3970 // update the index
3971 __ store(__ ctrl(), index_adr, next_index, index_bt, Compile::AliasIdxRaw, MemNode::unordered);
3972
3973 } __ else_(); {
3974
3975 // logging buffer is full, call the runtime
3976 const TypeFunc *tf = OptoRuntime::g1_wb_pre_Type();
3977 __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_pre), "g1_wb_pre", pre_val, tls);
3978 } __ end_if(); // (!index)
3979 } __ end_if(); // (pre_val != NULL)
3980 } __ end_if(); // (!marking)
3981
3982 // Final sync IdealKit and GraphKit.
3983 final_sync(ideal);
3984 }
3985
3986 //
3987 // Update the card table and add card address to the queue
3988 //
3989 void GraphKit::g1_mark_card(IdealKit& ideal,
3990 Node* card_adr,
3991 Node* oop_store,
3992 uint oop_alias_idx,
3993 Node* index,
3994 Node* index_adr,
3995 Node* buffer,
3996 const TypeFunc* tf) {
3997
3998 Node* zero = __ ConI(0);
3999 Node* zeroX = __ ConX(0);
4000 Node* no_base = __ top();
4001 BasicType card_bt = T_BYTE;
4002 // Smash zero into card. MUST BE ORDERED WRT TO STORE
4003 __ storeCM(__ ctrl(), card_adr, zero, oop_store, oop_alias_idx, card_bt, Compile::AliasIdxRaw);
4004
4005 // Now do the queue work
4006 __ if_then(index, BoolTest::ne, zeroX); {
4007
4008 Node* next_index = _gvn.transform(new SubXNode(index, __ ConX(sizeof(intptr_t))));
4009 Node* log_addr = __ AddP(no_base, buffer, next_index);
4010
4011 // Order, see storeCM.
4012 __ store(__ ctrl(), log_addr, card_adr, T_ADDRESS, Compile::AliasIdxRaw, MemNode::unordered);
4013 __ store(__ ctrl(), index_adr, next_index, TypeX_X->basic_type(), Compile::AliasIdxRaw, MemNode::unordered);
4014
4015 } __ else_(); {
4016 __ make_leaf_call(tf, CAST_FROM_FN_PTR(address, SharedRuntime::g1_wb_post), "g1_wb_post", card_adr, __ thread());
4017 } __ end_if();
4018
4019 }
4020
4021 void GraphKit::g1_write_barrier_post(Node* oop_store,
4022 Node* obj,
4023 Node* adr,
4024 uint alias_idx,
4025 Node* val,
4026 BasicType bt,
4027 bool use_precise) {
4028 // If we are writing a NULL then we need no post barrier
4029
4030 if (val != NULL && val->is_Con() && val->bottom_type() == TypePtr::NULL_PTR) {
4031 // Must be NULL
4032 const Type* t = val->bottom_type();
4033 assert(t == Type::TOP || t == TypePtr::NULL_PTR, "must be NULL");
4034 // No post barrier if writing NULLx
4035 return;
4036 }
4037
4038 if (!use_precise) {
4039 // All card marks for a (non-array) instance are in one place:
4040 adr = obj;
4041 }
4042 // (Else it's an array (or unknown), and we want more precise card marks.)
4043 assert(adr != NULL, "");
4044
4045 IdealKit ideal(this, true);
4046
4047 Node* tls = __ thread(); // ThreadLocalStorage
4048
4049 Node* no_base = __ top();
4050 float likely = PROB_LIKELY(0.999);
4051 float unlikely = PROB_UNLIKELY(0.999);
4052 Node* young_card = __ ConI((jint)G1SATBCardTableModRefBS::g1_young_card_val());
4053 Node* dirty_card = __ ConI((jint)CardTableModRefBS::dirty_card_val());
4054 Node* zeroX = __ ConX(0);
4055
4056 // Get the alias_index for raw card-mark memory
4057 const TypePtr* card_type = TypeRawPtr::BOTTOM;
4058
4059 const TypeFunc *tf = OptoRuntime::g1_wb_post_Type();
4060
4061 // Offsets into the thread
4062 const int index_offset = in_bytes(JavaThread::dirty_card_queue_offset() +
4063 PtrQueue::byte_offset_of_index());
4064 const int buffer_offset = in_bytes(JavaThread::dirty_card_queue_offset() +
4065 PtrQueue::byte_offset_of_buf());
4066
4067 // Pointers into the thread
4068
4069 Node* buffer_adr = __ AddP(no_base, tls, __ ConX(buffer_offset));
4070 Node* index_adr = __ AddP(no_base, tls, __ ConX(index_offset));
4071
4072 // Now some values
4073 // Use ctrl to avoid hoisting these values past a safepoint, which could
4074 // potentially reset these fields in the JavaThread.
4075 Node* index = __ load(__ ctrl(), index_adr, TypeX_X, TypeX_X->basic_type(), Compile::AliasIdxRaw);
4076 Node* buffer = __ load(__ ctrl(), buffer_adr, TypeRawPtr::NOTNULL, T_ADDRESS, Compile::AliasIdxRaw);
4077
4078 // Convert the store obj pointer to an int prior to doing math on it
4079 // Must use ctrl to prevent "integerized oop" existing across safepoint
4080 Node* cast = __ CastPX(__ ctrl(), adr);
4081
4082 // Divide pointer by card size
4083 Node* card_offset = __ URShiftX( cast, __ ConI(CardTableModRefBS::card_shift) );
4084
4085 // Combine card table base and card offset
4086 Node* card_adr = __ AddP(no_base, byte_map_base_node(), card_offset );
4087
4088 // If we know the value being stored does it cross regions?
4089
4090 if (val != NULL) {
4091 // Does the store cause us to cross regions?
4092
4093 // Should be able to do an unsigned compare of region_size instead of
4094 // and extra shift. Do we have an unsigned compare??
4095 // Node* region_size = __ ConI(1 << HeapRegion::LogOfHRGrainBytes);
4096 Node* xor_res = __ URShiftX ( __ XorX( cast, __ CastPX(__ ctrl(), val)), __ ConI(HeapRegion::LogOfHRGrainBytes));
4097
4098 // if (xor_res == 0) same region so skip
4099 __ if_then(xor_res, BoolTest::ne, zeroX); {
4100
4101 // No barrier if we are storing a NULL
4102 __ if_then(val, BoolTest::ne, null(), unlikely); {
4103
4104 // Ok must mark the card if not already dirty
4105
4106 // load the original value of the card
4107 Node* card_val = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw);
4108
4109 __ if_then(card_val, BoolTest::ne, young_card); {
4110 sync_kit(ideal);
4111 // Use Op_MemBarVolatile to achieve the effect of a StoreLoad barrier.
4112 insert_mem_bar(Op_MemBarVolatile, oop_store);
4113 __ sync_kit(this);
4114
4115 Node* card_val_reload = __ load(__ ctrl(), card_adr, TypeInt::INT, T_BYTE, Compile::AliasIdxRaw);
4116 __ if_then(card_val_reload, BoolTest::ne, dirty_card); {
4117 g1_mark_card(ideal, card_adr, oop_store, alias_idx, index, index_adr, buffer, tf);
4118 } __ end_if();
4119 } __ end_if();
4120 } __ end_if();
4121 } __ end_if();
4122 } else {
4123 // Object.clone() instrinsic uses this path.
4124 g1_mark_card(ideal, card_adr, oop_store, alias_idx, index, index_adr, buffer, tf);
4125 }
4126
4127 // Final sync IdealKit and GraphKit.
4128 final_sync(ideal);
4129 }
4130 #undef __
4131
4132
4133
4134 Node* GraphKit::load_String_offset(Node* ctrl, Node* str) {
4135 if (java_lang_String::has_offset_field()) {
4136 int offset_offset = java_lang_String::offset_offset_in_bytes();
4137 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4138 false, NULL, 0);
4139 const TypePtr* offset_field_type = string_type->add_offset(offset_offset);
4140 int offset_field_idx = C->get_alias_index(offset_field_type);
4141 return make_load(ctrl,
4142 basic_plus_adr(str, str, offset_offset),
4143 TypeInt::INT, T_INT, offset_field_idx, MemNode::unordered);
4144 } else {
4145 return intcon(0);
4146 }
4147 }
4148
4149 Node* GraphKit::load_String_length(Node* ctrl, Node* str) {
4150 if (java_lang_String::has_count_field()) {
4151 int count_offset = java_lang_String::count_offset_in_bytes();
4152 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4153 false, NULL, 0);
4154 const TypePtr* count_field_type = string_type->add_offset(count_offset);
4155 int count_field_idx = C->get_alias_index(count_field_type);
4156 return make_load(ctrl,
4157 basic_plus_adr(str, str, count_offset),
4158 TypeInt::INT, T_INT, count_field_idx, MemNode::unordered);
4159 } else {
4160 return load_array_length(load_String_value(ctrl, str));
4161 }
4162 }
4163
4164 Node* GraphKit::load_String_value(Node* ctrl, Node* str) {
4165 int value_offset = java_lang_String::value_offset_in_bytes();
4166 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4167 false, NULL, 0);
4168 const TypePtr* value_field_type = string_type->add_offset(value_offset);
4169 const TypeAryPtr* value_type = TypeAryPtr::make(TypePtr::NotNull,
4170 TypeAry::make(TypeInt::CHAR,TypeInt::POS),
4171 ciTypeArrayKlass::make(T_CHAR), true, 0);
4172 int value_field_idx = C->get_alias_index(value_field_type);
4173 Node* load = make_load(ctrl, basic_plus_adr(str, str, value_offset),
4174 value_type, T_OBJECT, value_field_idx, MemNode::unordered);
4175 // String.value field is known to be @Stable.
4176 if (UseImplicitStableValues) {
4177 load = cast_array_to_stable(load, value_type);
4178 }
4179 return load;
4180 }
4181
4182 void GraphKit::store_String_offset(Node* ctrl, Node* str, Node* value) {
4183 int offset_offset = java_lang_String::offset_offset_in_bytes();
4184 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4185 false, NULL, 0);
4186 const TypePtr* offset_field_type = string_type->add_offset(offset_offset);
4187 int offset_field_idx = C->get_alias_index(offset_field_type);
4188 store_to_memory(ctrl, basic_plus_adr(str, offset_offset),
4189 value, T_INT, offset_field_idx, MemNode::unordered);
4190 }
4191
4192 void GraphKit::store_String_value(Node* ctrl, Node* str, Node* value) {
4193 int value_offset = java_lang_String::value_offset_in_bytes();
4194 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4195 false, NULL, 0);
4196 const TypePtr* value_field_type = string_type->add_offset(value_offset);
4197
4198 store_oop_to_object(ctrl, str, basic_plus_adr(str, value_offset), value_field_type,
4199 value, TypeAryPtr::CHARS, T_OBJECT, MemNode::unordered);
4200 }
4201
4202 void GraphKit::store_String_length(Node* ctrl, Node* str, Node* value) {
4203 int count_offset = java_lang_String::count_offset_in_bytes();
4204 const TypeInstPtr* string_type = TypeInstPtr::make(TypePtr::NotNull, C->env()->String_klass(),
4205 false, NULL, 0);
4206 const TypePtr* count_field_type = string_type->add_offset(count_offset);
4207 int count_field_idx = C->get_alias_index(count_field_type);
4208 store_to_memory(ctrl, basic_plus_adr(str, count_offset),
4209 value, T_INT, count_field_idx, MemNode::unordered);
4210 }
4211
4212 Node* GraphKit::cast_array_to_stable(Node* ary, const TypeAryPtr* ary_type) {
4213 // Reify the property as a CastPP node in Ideal graph to comply with monotonicity
4214 // assumption of CCP analysis.
4215 return _gvn.transform(new CastPPNode(ary, ary_type->cast_to_stable(true)));
4216 }