Mon, 25 May 2020 14:24:27 +0800
8244407: JVM crashes after transformation in C2 IdealLoopTree::split_fall_in
Reviewed-by: thartmann, kvn, andrew
Contributed-by: zhouyong44@huawei.com
1 /*
2 * Copyright (c) 1997, 2015, 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 */
25 #include "precompiled.hpp"
26 #include "compiler/compileLog.hpp"
27 #include "ci/bcEscapeAnalyzer.hpp"
28 #include "compiler/oopMap.hpp"
29 #include "opto/callGenerator.hpp"
30 #include "opto/callnode.hpp"
31 #include "opto/escape.hpp"
32 #include "opto/locknode.hpp"
33 #include "opto/machnode.hpp"
34 #include "opto/matcher.hpp"
35 #include "opto/parse.hpp"
36 #include "opto/regalloc.hpp"
37 #include "opto/regmask.hpp"
38 #include "opto/rootnode.hpp"
39 #include "opto/runtime.hpp"
41 // Portions of code courtesy of Clifford Click
43 // Optimization - Graph Style
45 //=============================================================================
46 uint StartNode::size_of() const { return sizeof(*this); }
47 uint StartNode::cmp( const Node &n ) const
48 { return _domain == ((StartNode&)n)._domain; }
49 const Type *StartNode::bottom_type() const { return _domain; }
50 const Type *StartNode::Value(PhaseTransform *phase) const { return _domain; }
51 #ifndef PRODUCT
52 void StartNode::dump_spec(outputStream *st) const { st->print(" #"); _domain->dump_on(st);}
53 #endif
55 //------------------------------Ideal------------------------------------------
56 Node *StartNode::Ideal(PhaseGVN *phase, bool can_reshape){
57 return remove_dead_region(phase, can_reshape) ? this : NULL;
58 }
60 //------------------------------calling_convention-----------------------------
61 void StartNode::calling_convention( BasicType* sig_bt, VMRegPair *parm_regs, uint argcnt ) const {
62 Matcher::calling_convention( sig_bt, parm_regs, argcnt, false );
63 }
65 //------------------------------Registers--------------------------------------
66 const RegMask &StartNode::in_RegMask(uint) const {
67 return RegMask::Empty;
68 }
70 //------------------------------match------------------------------------------
71 // Construct projections for incoming parameters, and their RegMask info
72 Node *StartNode::match( const ProjNode *proj, const Matcher *match ) {
73 switch (proj->_con) {
74 case TypeFunc::Control:
75 case TypeFunc::I_O:
76 case TypeFunc::Memory:
77 return new (match->C) MachProjNode(this,proj->_con,RegMask::Empty,MachProjNode::unmatched_proj);
78 case TypeFunc::FramePtr:
79 return new (match->C) MachProjNode(this,proj->_con,Matcher::c_frame_ptr_mask, Op_RegP);
80 case TypeFunc::ReturnAdr:
81 return new (match->C) MachProjNode(this,proj->_con,match->_return_addr_mask,Op_RegP);
82 case TypeFunc::Parms:
83 default: {
84 uint parm_num = proj->_con - TypeFunc::Parms;
85 const Type *t = _domain->field_at(proj->_con);
86 if (t->base() == Type::Half) // 2nd half of Longs and Doubles
87 return new (match->C) ConNode(Type::TOP);
88 uint ideal_reg = t->ideal_reg();
89 RegMask &rm = match->_calling_convention_mask[parm_num];
90 return new (match->C) MachProjNode(this,proj->_con,rm,ideal_reg);
91 }
92 }
93 return NULL;
94 }
96 //------------------------------StartOSRNode----------------------------------
97 // The method start node for an on stack replacement adapter
99 //------------------------------osr_domain-----------------------------
100 const TypeTuple *StartOSRNode::osr_domain() {
101 const Type **fields = TypeTuple::fields(2);
102 fields[TypeFunc::Parms+0] = TypeRawPtr::BOTTOM; // address of osr buffer
104 return TypeTuple::make(TypeFunc::Parms+1, fields);
105 }
107 //=============================================================================
108 const char * const ParmNode::names[TypeFunc::Parms+1] = {
109 "Control", "I_O", "Memory", "FramePtr", "ReturnAdr", "Parms"
110 };
112 #ifndef PRODUCT
113 void ParmNode::dump_spec(outputStream *st) const {
114 if( _con < TypeFunc::Parms ) {
115 st->print("%s", names[_con]);
116 } else {
117 st->print("Parm%d: ",_con-TypeFunc::Parms);
118 // Verbose and WizardMode dump bottom_type for all nodes
119 if( !Verbose && !WizardMode ) bottom_type()->dump_on(st);
120 }
121 }
122 #endif
124 uint ParmNode::ideal_reg() const {
125 switch( _con ) {
126 case TypeFunc::Control : // fall through
127 case TypeFunc::I_O : // fall through
128 case TypeFunc::Memory : return 0;
129 case TypeFunc::FramePtr : // fall through
130 case TypeFunc::ReturnAdr: return Op_RegP;
131 default : assert( _con > TypeFunc::Parms, "" );
132 // fall through
133 case TypeFunc::Parms : {
134 // Type of argument being passed
135 const Type *t = in(0)->as_Start()->_domain->field_at(_con);
136 return t->ideal_reg();
137 }
138 }
139 ShouldNotReachHere();
140 return 0;
141 }
143 //=============================================================================
144 ReturnNode::ReturnNode(uint edges, Node *cntrl, Node *i_o, Node *memory, Node *frameptr, Node *retadr ) : Node(edges) {
145 init_req(TypeFunc::Control,cntrl);
146 init_req(TypeFunc::I_O,i_o);
147 init_req(TypeFunc::Memory,memory);
148 init_req(TypeFunc::FramePtr,frameptr);
149 init_req(TypeFunc::ReturnAdr,retadr);
150 }
152 Node *ReturnNode::Ideal(PhaseGVN *phase, bool can_reshape){
153 return remove_dead_region(phase, can_reshape) ? this : NULL;
154 }
156 const Type *ReturnNode::Value( PhaseTransform *phase ) const {
157 return ( phase->type(in(TypeFunc::Control)) == Type::TOP)
158 ? Type::TOP
159 : Type::BOTTOM;
160 }
162 // Do we Match on this edge index or not? No edges on return nodes
163 uint ReturnNode::match_edge(uint idx) const {
164 return 0;
165 }
168 #ifndef PRODUCT
169 void ReturnNode::dump_req(outputStream *st) const {
170 // Dump the required inputs, enclosed in '(' and ')'
171 uint i; // Exit value of loop
172 for (i = 0; i < req(); i++) { // For all required inputs
173 if (i == TypeFunc::Parms) st->print("returns");
174 if (in(i)) st->print("%c%d ", Compile::current()->node_arena()->contains(in(i)) ? ' ' : 'o', in(i)->_idx);
175 else st->print("_ ");
176 }
177 }
178 #endif
180 //=============================================================================
181 RethrowNode::RethrowNode(
182 Node* cntrl,
183 Node* i_o,
184 Node* memory,
185 Node* frameptr,
186 Node* ret_adr,
187 Node* exception
188 ) : Node(TypeFunc::Parms + 1) {
189 init_req(TypeFunc::Control , cntrl );
190 init_req(TypeFunc::I_O , i_o );
191 init_req(TypeFunc::Memory , memory );
192 init_req(TypeFunc::FramePtr , frameptr );
193 init_req(TypeFunc::ReturnAdr, ret_adr);
194 init_req(TypeFunc::Parms , exception);
195 }
197 Node *RethrowNode::Ideal(PhaseGVN *phase, bool can_reshape){
198 return remove_dead_region(phase, can_reshape) ? this : NULL;
199 }
201 const Type *RethrowNode::Value( PhaseTransform *phase ) const {
202 return (phase->type(in(TypeFunc::Control)) == Type::TOP)
203 ? Type::TOP
204 : Type::BOTTOM;
205 }
207 uint RethrowNode::match_edge(uint idx) const {
208 return 0;
209 }
211 #ifndef PRODUCT
212 void RethrowNode::dump_req(outputStream *st) const {
213 // Dump the required inputs, enclosed in '(' and ')'
214 uint i; // Exit value of loop
215 for (i = 0; i < req(); i++) { // For all required inputs
216 if (i == TypeFunc::Parms) st->print("exception");
217 if (in(i)) st->print("%c%d ", Compile::current()->node_arena()->contains(in(i)) ? ' ' : 'o', in(i)->_idx);
218 else st->print("_ ");
219 }
220 }
221 #endif
223 //=============================================================================
224 // Do we Match on this edge index or not? Match only target address & method
225 uint TailCallNode::match_edge(uint idx) const {
226 return TypeFunc::Parms <= idx && idx <= TypeFunc::Parms+1;
227 }
229 //=============================================================================
230 // Do we Match on this edge index or not? Match only target address & oop
231 uint TailJumpNode::match_edge(uint idx) const {
232 return TypeFunc::Parms <= idx && idx <= TypeFunc::Parms+1;
233 }
235 //=============================================================================
236 JVMState::JVMState(ciMethod* method, JVMState* caller) :
237 _method(method) {
238 assert(method != NULL, "must be valid call site");
239 _reexecute = Reexecute_Undefined;
240 debug_only(_bci = -99); // random garbage value
241 debug_only(_map = (SafePointNode*)-1);
242 _caller = caller;
243 _depth = 1 + (caller == NULL ? 0 : caller->depth());
244 _locoff = TypeFunc::Parms;
245 _stkoff = _locoff + _method->max_locals();
246 _monoff = _stkoff + _method->max_stack();
247 _scloff = _monoff;
248 _endoff = _monoff;
249 _sp = 0;
250 }
251 JVMState::JVMState(int stack_size) :
252 _method(NULL) {
253 _bci = InvocationEntryBci;
254 _reexecute = Reexecute_Undefined;
255 debug_only(_map = (SafePointNode*)-1);
256 _caller = NULL;
257 _depth = 1;
258 _locoff = TypeFunc::Parms;
259 _stkoff = _locoff;
260 _monoff = _stkoff + stack_size;
261 _scloff = _monoff;
262 _endoff = _monoff;
263 _sp = 0;
264 }
266 //--------------------------------of_depth-------------------------------------
267 JVMState* JVMState::of_depth(int d) const {
268 const JVMState* jvmp = this;
269 assert(0 < d && (uint)d <= depth(), "oob");
270 for (int skip = depth() - d; skip > 0; skip--) {
271 jvmp = jvmp->caller();
272 }
273 assert(jvmp->depth() == (uint)d, "found the right one");
274 return (JVMState*)jvmp;
275 }
277 //-----------------------------same_calls_as-----------------------------------
278 bool JVMState::same_calls_as(const JVMState* that) const {
279 if (this == that) return true;
280 if (this->depth() != that->depth()) return false;
281 const JVMState* p = this;
282 const JVMState* q = that;
283 for (;;) {
284 if (p->_method != q->_method) return false;
285 if (p->_method == NULL) return true; // bci is irrelevant
286 if (p->_bci != q->_bci) return false;
287 if (p->_reexecute != q->_reexecute) return false;
288 p = p->caller();
289 q = q->caller();
290 if (p == q) return true;
291 assert(p != NULL && q != NULL, "depth check ensures we don't run off end");
292 }
293 }
295 //------------------------------debug_start------------------------------------
296 uint JVMState::debug_start() const {
297 debug_only(JVMState* jvmroot = of_depth(1));
298 assert(jvmroot->locoff() <= this->locoff(), "youngest JVMState must be last");
299 return of_depth(1)->locoff();
300 }
302 //-------------------------------debug_end-------------------------------------
303 uint JVMState::debug_end() const {
304 debug_only(JVMState* jvmroot = of_depth(1));
305 assert(jvmroot->endoff() <= this->endoff(), "youngest JVMState must be last");
306 return endoff();
307 }
309 //------------------------------debug_depth------------------------------------
310 uint JVMState::debug_depth() const {
311 uint total = 0;
312 for (const JVMState* jvmp = this; jvmp != NULL; jvmp = jvmp->caller()) {
313 total += jvmp->debug_size();
314 }
315 return total;
316 }
318 #ifndef PRODUCT
320 //------------------------------format_helper----------------------------------
321 // Given an allocation (a Chaitin object) and a Node decide if the Node carries
322 // any defined value or not. If it does, print out the register or constant.
323 static void format_helper( PhaseRegAlloc *regalloc, outputStream* st, Node *n, const char *msg, uint i, GrowableArray<SafePointScalarObjectNode*> *scobjs ) {
324 if (n == NULL) { st->print(" NULL"); return; }
325 if (n->is_SafePointScalarObject()) {
326 // Scalar replacement.
327 SafePointScalarObjectNode* spobj = n->as_SafePointScalarObject();
328 scobjs->append_if_missing(spobj);
329 int sco_n = scobjs->find(spobj);
330 assert(sco_n >= 0, "");
331 st->print(" %s%d]=#ScObj" INT32_FORMAT, msg, i, sco_n);
332 return;
333 }
334 if (regalloc->node_regs_max_index() > 0 &&
335 OptoReg::is_valid(regalloc->get_reg_first(n))) { // Check for undefined
336 char buf[50];
337 regalloc->dump_register(n,buf);
338 st->print(" %s%d]=%s",msg,i,buf);
339 } else { // No register, but might be constant
340 const Type *t = n->bottom_type();
341 switch (t->base()) {
342 case Type::Int:
343 st->print(" %s%d]=#" INT32_FORMAT,msg,i,t->is_int()->get_con());
344 break;
345 case Type::AnyPtr:
346 assert( t == TypePtr::NULL_PTR || n->in_dump(), "" );
347 st->print(" %s%d]=#NULL",msg,i);
348 break;
349 case Type::AryPtr:
350 case Type::InstPtr:
351 st->print(" %s%d]=#Ptr" INTPTR_FORMAT,msg,i,p2i(t->isa_oopptr()->const_oop()));
352 break;
353 case Type::KlassPtr:
354 st->print(" %s%d]=#Ptr" INTPTR_FORMAT,msg,i,p2i(t->make_ptr()->isa_klassptr()->klass()));
355 break;
356 case Type::MetadataPtr:
357 st->print(" %s%d]=#Ptr" INTPTR_FORMAT,msg,i,p2i(t->make_ptr()->isa_metadataptr()->metadata()));
358 break;
359 case Type::NarrowOop:
360 st->print(" %s%d]=#Ptr" INTPTR_FORMAT,msg,i,p2i(t->make_ptr()->isa_oopptr()->const_oop()));
361 break;
362 case Type::RawPtr:
363 st->print(" %s%d]=#Raw" INTPTR_FORMAT,msg,i,p2i(t->is_rawptr()));
364 break;
365 case Type::DoubleCon:
366 st->print(" %s%d]=#%fD",msg,i,t->is_double_constant()->_d);
367 break;
368 case Type::FloatCon:
369 st->print(" %s%d]=#%fF",msg,i,t->is_float_constant()->_f);
370 break;
371 case Type::Long:
372 st->print(" %s%d]=#" INT64_FORMAT,msg,i,(int64_t)(t->is_long()->get_con()));
373 break;
374 case Type::Half:
375 case Type::Top:
376 st->print(" %s%d]=_",msg,i);
377 break;
378 default: ShouldNotReachHere();
379 }
380 }
381 }
383 //------------------------------format-----------------------------------------
384 void JVMState::format(PhaseRegAlloc *regalloc, const Node *n, outputStream* st) const {
385 st->print(" #");
386 if (_method) {
387 _method->print_short_name(st);
388 st->print(" @ bci:%d ",_bci);
389 } else {
390 st->print_cr(" runtime stub ");
391 return;
392 }
393 if (n->is_MachSafePoint()) {
394 GrowableArray<SafePointScalarObjectNode*> scobjs;
395 MachSafePointNode *mcall = n->as_MachSafePoint();
396 uint i;
397 // Print locals
398 for (i = 0; i < (uint)loc_size(); i++)
399 format_helper(regalloc, st, mcall->local(this, i), "L[", i, &scobjs);
400 // Print stack
401 for (i = 0; i < (uint)stk_size(); i++) {
402 if ((uint)(_stkoff + i) >= mcall->len())
403 st->print(" oob ");
404 else
405 format_helper(regalloc, st, mcall->stack(this, i), "STK[", i, &scobjs);
406 }
407 for (i = 0; (int)i < nof_monitors(); i++) {
408 Node *box = mcall->monitor_box(this, i);
409 Node *obj = mcall->monitor_obj(this, i);
410 if (regalloc->node_regs_max_index() > 0 &&
411 OptoReg::is_valid(regalloc->get_reg_first(box))) {
412 box = BoxLockNode::box_node(box);
413 format_helper(regalloc, st, box, "MON-BOX[", i, &scobjs);
414 } else {
415 OptoReg::Name box_reg = BoxLockNode::reg(box);
416 st->print(" MON-BOX%d=%s+%d",
417 i,
418 OptoReg::regname(OptoReg::c_frame_pointer),
419 regalloc->reg2offset(box_reg));
420 }
421 const char* obj_msg = "MON-OBJ[";
422 if (EliminateLocks) {
423 if (BoxLockNode::box_node(box)->is_eliminated())
424 obj_msg = "MON-OBJ(LOCK ELIMINATED)[";
425 }
426 format_helper(regalloc, st, obj, obj_msg, i, &scobjs);
427 }
429 for (i = 0; i < (uint)scobjs.length(); i++) {
430 // Scalar replaced objects.
431 st->cr();
432 st->print(" # ScObj" INT32_FORMAT " ", i);
433 SafePointScalarObjectNode* spobj = scobjs.at(i);
434 ciKlass* cik = spobj->bottom_type()->is_oopptr()->klass();
435 assert(cik->is_instance_klass() ||
436 cik->is_array_klass(), "Not supported allocation.");
437 ciInstanceKlass *iklass = NULL;
438 if (cik->is_instance_klass()) {
439 cik->print_name_on(st);
440 iklass = cik->as_instance_klass();
441 } else if (cik->is_type_array_klass()) {
442 cik->as_array_klass()->base_element_type()->print_name_on(st);
443 st->print("[%d]", spobj->n_fields());
444 } else if (cik->is_obj_array_klass()) {
445 ciKlass* cie = cik->as_obj_array_klass()->base_element_klass();
446 if (cie->is_instance_klass()) {
447 cie->print_name_on(st);
448 } else if (cie->is_type_array_klass()) {
449 cie->as_array_klass()->base_element_type()->print_name_on(st);
450 } else {
451 ShouldNotReachHere();
452 }
453 st->print("[%d]", spobj->n_fields());
454 int ndim = cik->as_array_klass()->dimension() - 1;
455 while (ndim-- > 0) {
456 st->print("[]");
457 }
458 }
459 st->print("={");
460 uint nf = spobj->n_fields();
461 if (nf > 0) {
462 uint first_ind = spobj->first_index(mcall->jvms());
463 Node* fld_node = mcall->in(first_ind);
464 ciField* cifield;
465 if (iklass != NULL) {
466 st->print(" [");
467 cifield = iklass->nonstatic_field_at(0);
468 cifield->print_name_on(st);
469 format_helper(regalloc, st, fld_node, ":", 0, &scobjs);
470 } else {
471 format_helper(regalloc, st, fld_node, "[", 0, &scobjs);
472 }
473 for (uint j = 1; j < nf; j++) {
474 fld_node = mcall->in(first_ind+j);
475 if (iklass != NULL) {
476 st->print(", [");
477 cifield = iklass->nonstatic_field_at(j);
478 cifield->print_name_on(st);
479 format_helper(regalloc, st, fld_node, ":", j, &scobjs);
480 } else {
481 format_helper(regalloc, st, fld_node, ", [", j, &scobjs);
482 }
483 }
484 }
485 st->print(" }");
486 }
487 }
488 st->cr();
489 if (caller() != NULL) caller()->format(regalloc, n, st);
490 }
493 void JVMState::dump_spec(outputStream *st) const {
494 if (_method != NULL) {
495 bool printed = false;
496 if (!Verbose) {
497 // The JVMS dumps make really, really long lines.
498 // Take out the most boring parts, which are the package prefixes.
499 char buf[500];
500 stringStream namest(buf, sizeof(buf));
501 _method->print_short_name(&namest);
502 if (namest.count() < sizeof(buf)) {
503 const char* name = namest.base();
504 if (name[0] == ' ') ++name;
505 const char* endcn = strchr(name, ':'); // end of class name
506 if (endcn == NULL) endcn = strchr(name, '(');
507 if (endcn == NULL) endcn = name + strlen(name);
508 while (endcn > name && endcn[-1] != '.' && endcn[-1] != '/')
509 --endcn;
510 st->print(" %s", endcn);
511 printed = true;
512 }
513 }
514 if (!printed)
515 _method->print_short_name(st);
516 st->print(" @ bci:%d",_bci);
517 if(_reexecute == Reexecute_True)
518 st->print(" reexecute");
519 } else {
520 st->print(" runtime stub");
521 }
522 if (caller() != NULL) caller()->dump_spec(st);
523 }
526 void JVMState::dump_on(outputStream* st) const {
527 bool print_map = _map && !((uintptr_t)_map & 1) &&
528 ((caller() == NULL) || (caller()->map() != _map));
529 if (print_map) {
530 if (_map->len() > _map->req()) { // _map->has_exceptions()
531 Node* ex = _map->in(_map->req()); // _map->next_exception()
532 // skip the first one; it's already being printed
533 while (ex != NULL && ex->len() > ex->req()) {
534 ex = ex->in(ex->req()); // ex->next_exception()
535 ex->dump(1);
536 }
537 }
538 _map->dump(Verbose ? 2 : 1);
539 }
540 if (caller() != NULL) {
541 caller()->dump_on(st);
542 }
543 st->print("JVMS depth=%d loc=%d stk=%d arg=%d mon=%d scalar=%d end=%d mondepth=%d sp=%d bci=%d reexecute=%s method=",
544 depth(), locoff(), stkoff(), argoff(), monoff(), scloff(), endoff(), monitor_depth(), sp(), bci(), should_reexecute()?"true":"false");
545 if (_method == NULL) {
546 st->print_cr("(none)");
547 } else {
548 _method->print_name(st);
549 st->cr();
550 if (bci() >= 0 && bci() < _method->code_size()) {
551 st->print(" bc: ");
552 _method->print_codes_on(bci(), bci()+1, st);
553 }
554 }
555 }
557 // Extra way to dump a jvms from the debugger,
558 // to avoid a bug with C++ member function calls.
559 void dump_jvms(JVMState* jvms) {
560 jvms->dump();
561 }
562 #endif
564 //--------------------------clone_shallow--------------------------------------
565 JVMState* JVMState::clone_shallow(Compile* C) const {
566 JVMState* n = has_method() ? new (C) JVMState(_method, _caller) : new (C) JVMState(0);
567 n->set_bci(_bci);
568 n->_reexecute = _reexecute;
569 n->set_locoff(_locoff);
570 n->set_stkoff(_stkoff);
571 n->set_monoff(_monoff);
572 n->set_scloff(_scloff);
573 n->set_endoff(_endoff);
574 n->set_sp(_sp);
575 n->set_map(_map);
576 return n;
577 }
579 //---------------------------clone_deep----------------------------------------
580 JVMState* JVMState::clone_deep(Compile* C) const {
581 JVMState* n = clone_shallow(C);
582 for (JVMState* p = n; p->_caller != NULL; p = p->_caller) {
583 p->_caller = p->_caller->clone_shallow(C);
584 }
585 assert(n->depth() == depth(), "sanity");
586 assert(n->debug_depth() == debug_depth(), "sanity");
587 return n;
588 }
590 /**
591 * Reset map for all callers
592 */
593 void JVMState::set_map_deep(SafePointNode* map) {
594 for (JVMState* p = this; p->_caller != NULL; p = p->_caller) {
595 p->set_map(map);
596 }
597 }
599 // Adapt offsets in in-array after adding or removing an edge.
600 // Prerequisite is that the JVMState is used by only one node.
601 void JVMState::adapt_position(int delta) {
602 for (JVMState* jvms = this; jvms != NULL; jvms = jvms->caller()) {
603 jvms->set_locoff(jvms->locoff() + delta);
604 jvms->set_stkoff(jvms->stkoff() + delta);
605 jvms->set_monoff(jvms->monoff() + delta);
606 jvms->set_scloff(jvms->scloff() + delta);
607 jvms->set_endoff(jvms->endoff() + delta);
608 }
609 }
611 // Mirror the stack size calculation in the deopt code
612 // How much stack space would we need at this point in the program in
613 // case of deoptimization?
614 int JVMState::interpreter_frame_size() const {
615 const JVMState* jvms = this;
616 int size = 0;
617 int callee_parameters = 0;
618 int callee_locals = 0;
619 int extra_args = method()->max_stack() - stk_size();
621 while (jvms != NULL) {
622 int locks = jvms->nof_monitors();
623 int temps = jvms->stk_size();
624 bool is_top_frame = (jvms == this);
625 ciMethod* method = jvms->method();
627 int frame_size = BytesPerWord * Interpreter::size_activation(method->max_stack(),
628 temps + callee_parameters,
629 extra_args,
630 locks,
631 callee_parameters,
632 callee_locals,
633 is_top_frame);
634 size += frame_size;
636 callee_parameters = method->size_of_parameters();
637 callee_locals = method->max_locals();
638 extra_args = 0;
639 jvms = jvms->caller();
640 }
641 return size + Deoptimization::last_frame_adjust(0, callee_locals) * BytesPerWord;
642 }
644 //=============================================================================
645 uint CallNode::cmp( const Node &n ) const
646 { return _tf == ((CallNode&)n)._tf && _jvms == ((CallNode&)n)._jvms; }
647 #ifndef PRODUCT
648 void CallNode::dump_req(outputStream *st) const {
649 // Dump the required inputs, enclosed in '(' and ')'
650 uint i; // Exit value of loop
651 for (i = 0; i < req(); i++) { // For all required inputs
652 if (i == TypeFunc::Parms) st->print("(");
653 if (in(i)) st->print("%c%d ", Compile::current()->node_arena()->contains(in(i)) ? ' ' : 'o', in(i)->_idx);
654 else st->print("_ ");
655 }
656 st->print(")");
657 }
659 void CallNode::dump_spec(outputStream *st) const {
660 st->print(" ");
661 tf()->dump_on(st);
662 if (_cnt != COUNT_UNKNOWN) st->print(" C=%f",_cnt);
663 if (jvms() != NULL) jvms()->dump_spec(st);
664 }
665 #endif
667 const Type *CallNode::bottom_type() const { return tf()->range(); }
668 const Type *CallNode::Value(PhaseTransform *phase) const {
669 if (phase->type(in(0)) == Type::TOP) return Type::TOP;
670 return tf()->range();
671 }
673 //------------------------------calling_convention-----------------------------
674 void CallNode::calling_convention( BasicType* sig_bt, VMRegPair *parm_regs, uint argcnt ) const {
675 // Use the standard compiler calling convention
676 Matcher::calling_convention( sig_bt, parm_regs, argcnt, true );
677 }
680 //------------------------------match------------------------------------------
681 // Construct projections for control, I/O, memory-fields, ..., and
682 // return result(s) along with their RegMask info
683 Node *CallNode::match( const ProjNode *proj, const Matcher *match ) {
684 switch (proj->_con) {
685 case TypeFunc::Control:
686 case TypeFunc::I_O:
687 case TypeFunc::Memory:
688 return new (match->C) MachProjNode(this,proj->_con,RegMask::Empty,MachProjNode::unmatched_proj);
690 case TypeFunc::Parms+1: // For LONG & DOUBLE returns
691 assert(tf()->_range->field_at(TypeFunc::Parms+1) == Type::HALF, "");
692 // 2nd half of doubles and longs
693 return new (match->C) MachProjNode(this,proj->_con, RegMask::Empty, (uint)OptoReg::Bad);
695 case TypeFunc::Parms: { // Normal returns
696 uint ideal_reg = tf()->range()->field_at(TypeFunc::Parms)->ideal_reg();
697 OptoRegPair regs = is_CallRuntime()
698 ? match->c_return_value(ideal_reg,true) // Calls into C runtime
699 : match-> return_value(ideal_reg,true); // Calls into compiled Java code
700 RegMask rm = RegMask(regs.first());
701 if( OptoReg::is_valid(regs.second()) )
702 rm.Insert( regs.second() );
703 return new (match->C) MachProjNode(this,proj->_con,rm,ideal_reg);
704 }
706 case TypeFunc::ReturnAdr:
707 case TypeFunc::FramePtr:
708 default:
709 ShouldNotReachHere();
710 }
711 return NULL;
712 }
714 // Do we Match on this edge index or not? Match no edges
715 uint CallNode::match_edge(uint idx) const {
716 return 0;
717 }
719 //
720 // Determine whether the call could modify the field of the specified
721 // instance at the specified offset.
722 //
723 bool CallNode::may_modify(const TypeOopPtr *t_oop, PhaseTransform *phase) {
724 assert((t_oop != NULL), "sanity");
725 if (t_oop->is_known_instance()) {
726 // The instance_id is set only for scalar-replaceable allocations which
727 // are not passed as arguments according to Escape Analysis.
728 return false;
729 }
730 if (t_oop->is_ptr_to_boxed_value()) {
731 ciKlass* boxing_klass = t_oop->klass();
732 if (is_CallStaticJava() && as_CallStaticJava()->is_boxing_method()) {
733 // Skip unrelated boxing methods.
734 Node* proj = proj_out(TypeFunc::Parms);
735 if ((proj == NULL) || (phase->type(proj)->is_instptr()->klass() != boxing_klass)) {
736 return false;
737 }
738 }
739 if (is_CallJava() && as_CallJava()->method() != NULL) {
740 ciMethod* meth = as_CallJava()->method();
741 if (meth->is_accessor()) {
742 return false;
743 }
744 // May modify (by reflection) if an boxing object is passed
745 // as argument or returned.
746 Node* proj = returns_pointer() ? proj_out(TypeFunc::Parms) : NULL;
747 if (proj != NULL) {
748 const TypeInstPtr* inst_t = phase->type(proj)->isa_instptr();
749 if ((inst_t != NULL) && (!inst_t->klass_is_exact() ||
750 (inst_t->klass() == boxing_klass))) {
751 return true;
752 }
753 }
754 const TypeTuple* d = tf()->domain();
755 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
756 const TypeInstPtr* inst_t = d->field_at(i)->isa_instptr();
757 if ((inst_t != NULL) && (!inst_t->klass_is_exact() ||
758 (inst_t->klass() == boxing_klass))) {
759 return true;
760 }
761 }
762 return false;
763 }
764 }
765 return true;
766 }
768 // Does this call have a direct reference to n other than debug information?
769 bool CallNode::has_non_debug_use(Node *n) {
770 const TypeTuple * d = tf()->domain();
771 for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
772 Node *arg = in(i);
773 if (arg == n) {
774 return true;
775 }
776 }
777 return false;
778 }
780 // Returns the unique CheckCastPP of a call
781 // or 'this' if there are several CheckCastPP or unexpected uses
782 // or returns NULL if there is no one.
783 Node *CallNode::result_cast() {
784 Node *cast = NULL;
786 Node *p = proj_out(TypeFunc::Parms);
787 if (p == NULL)
788 return NULL;
790 for (DUIterator_Fast imax, i = p->fast_outs(imax); i < imax; i++) {
791 Node *use = p->fast_out(i);
792 if (use->is_CheckCastPP()) {
793 if (cast != NULL) {
794 return this; // more than 1 CheckCastPP
795 }
796 cast = use;
797 } else if (!use->is_Initialize() &&
798 !use->is_AddP()) {
799 // Expected uses are restricted to a CheckCastPP, an Initialize
800 // node, and AddP nodes. If we encounter any other use (a Phi
801 // node can be seen in rare cases) return this to prevent
802 // incorrect optimizations.
803 return this;
804 }
805 }
806 return cast;
807 }
810 void CallNode::extract_projections(CallProjections* projs, bool separate_io_proj) {
811 projs->fallthrough_proj = NULL;
812 projs->fallthrough_catchproj = NULL;
813 projs->fallthrough_ioproj = NULL;
814 projs->catchall_ioproj = NULL;
815 projs->catchall_catchproj = NULL;
816 projs->fallthrough_memproj = NULL;
817 projs->catchall_memproj = NULL;
818 projs->resproj = NULL;
819 projs->exobj = NULL;
821 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
822 ProjNode *pn = fast_out(i)->as_Proj();
823 if (pn->outcnt() == 0) continue;
824 switch (pn->_con) {
825 case TypeFunc::Control:
826 {
827 // For Control (fallthrough) and I_O (catch_all_index) we have CatchProj -> Catch -> Proj
828 projs->fallthrough_proj = pn;
829 DUIterator_Fast jmax, j = pn->fast_outs(jmax);
830 const Node *cn = pn->fast_out(j);
831 if (cn->is_Catch()) {
832 ProjNode *cpn = NULL;
833 for (DUIterator_Fast kmax, k = cn->fast_outs(kmax); k < kmax; k++) {
834 cpn = cn->fast_out(k)->as_Proj();
835 assert(cpn->is_CatchProj(), "must be a CatchProjNode");
836 if (cpn->_con == CatchProjNode::fall_through_index)
837 projs->fallthrough_catchproj = cpn;
838 else {
839 assert(cpn->_con == CatchProjNode::catch_all_index, "must be correct index.");
840 projs->catchall_catchproj = cpn;
841 }
842 }
843 }
844 break;
845 }
846 case TypeFunc::I_O:
847 if (pn->_is_io_use)
848 projs->catchall_ioproj = pn;
849 else
850 projs->fallthrough_ioproj = pn;
851 for (DUIterator j = pn->outs(); pn->has_out(j); j++) {
852 Node* e = pn->out(j);
853 if (e->Opcode() == Op_CreateEx && e->in(0)->is_CatchProj() && e->outcnt() > 0) {
854 assert(projs->exobj == NULL, "only one");
855 projs->exobj = e;
856 }
857 }
858 break;
859 case TypeFunc::Memory:
860 if (pn->_is_io_use)
861 projs->catchall_memproj = pn;
862 else
863 projs->fallthrough_memproj = pn;
864 break;
865 case TypeFunc::Parms:
866 projs->resproj = pn;
867 break;
868 default:
869 assert(false, "unexpected projection from allocation node.");
870 }
871 }
873 // The resproj may not exist because the result couuld be ignored
874 // and the exception object may not exist if an exception handler
875 // swallows the exception but all the other must exist and be found.
876 assert(projs->fallthrough_proj != NULL, "must be found");
877 assert(Compile::current()->inlining_incrementally() || projs->fallthrough_catchproj != NULL, "must be found");
878 assert(Compile::current()->inlining_incrementally() || projs->fallthrough_memproj != NULL, "must be found");
879 assert(Compile::current()->inlining_incrementally() || projs->fallthrough_ioproj != NULL, "must be found");
880 assert(Compile::current()->inlining_incrementally() || projs->catchall_catchproj != NULL, "must be found");
881 if (separate_io_proj) {
882 assert(Compile::current()->inlining_incrementally() || projs->catchall_memproj != NULL, "must be found");
883 assert(Compile::current()->inlining_incrementally() || projs->catchall_ioproj != NULL, "must be found");
884 }
885 }
887 Node *CallNode::Ideal(PhaseGVN *phase, bool can_reshape) {
888 CallGenerator* cg = generator();
889 if (can_reshape && cg != NULL && cg->is_mh_late_inline() && !cg->already_attempted()) {
890 // Check whether this MH handle call becomes a candidate for inlining
891 ciMethod* callee = cg->method();
892 vmIntrinsics::ID iid = callee->intrinsic_id();
893 if (iid == vmIntrinsics::_invokeBasic) {
894 if (in(TypeFunc::Parms)->Opcode() == Op_ConP) {
895 phase->C->prepend_late_inline(cg);
896 set_generator(NULL);
897 }
898 } else {
899 assert(callee->has_member_arg(), "wrong type of call?");
900 if (in(TypeFunc::Parms + callee->arg_size() - 1)->Opcode() == Op_ConP) {
901 phase->C->prepend_late_inline(cg);
902 set_generator(NULL);
903 }
904 }
905 }
906 return SafePointNode::Ideal(phase, can_reshape);
907 }
910 //=============================================================================
911 uint CallJavaNode::size_of() const { return sizeof(*this); }
912 uint CallJavaNode::cmp( const Node &n ) const {
913 CallJavaNode &call = (CallJavaNode&)n;
914 return CallNode::cmp(call) && _method == call._method;
915 }
916 #ifndef PRODUCT
917 void CallJavaNode::dump_spec(outputStream *st) const {
918 if( _method ) _method->print_short_name(st);
919 CallNode::dump_spec(st);
920 }
921 #endif
923 //=============================================================================
924 uint CallStaticJavaNode::size_of() const { return sizeof(*this); }
925 uint CallStaticJavaNode::cmp( const Node &n ) const {
926 CallStaticJavaNode &call = (CallStaticJavaNode&)n;
927 return CallJavaNode::cmp(call);
928 }
930 //----------------------------uncommon_trap_request----------------------------
931 // If this is an uncommon trap, return the request code, else zero.
932 int CallStaticJavaNode::uncommon_trap_request() const {
933 if (_name != NULL && !strcmp(_name, "uncommon_trap")) {
934 return extract_uncommon_trap_request(this);
935 }
936 return 0;
937 }
938 int CallStaticJavaNode::extract_uncommon_trap_request(const Node* call) {
939 #ifndef PRODUCT
940 if (!(call->req() > TypeFunc::Parms &&
941 call->in(TypeFunc::Parms) != NULL &&
942 call->in(TypeFunc::Parms)->is_Con())) {
943 assert(in_dump() != 0, "OK if dumping");
944 tty->print("[bad uncommon trap]");
945 return 0;
946 }
947 #endif
948 return call->in(TypeFunc::Parms)->bottom_type()->is_int()->get_con();
949 }
951 #ifndef PRODUCT
952 void CallStaticJavaNode::dump_spec(outputStream *st) const {
953 st->print("# Static ");
954 if (_name != NULL) {
955 st->print("%s", _name);
956 int trap_req = uncommon_trap_request();
957 if (trap_req != 0) {
958 char buf[100];
959 st->print("(%s)",
960 Deoptimization::format_trap_request(buf, sizeof(buf),
961 trap_req));
962 }
963 st->print(" ");
964 }
965 CallJavaNode::dump_spec(st);
966 }
967 #endif
969 //=============================================================================
970 uint CallDynamicJavaNode::size_of() const { return sizeof(*this); }
971 uint CallDynamicJavaNode::cmp( const Node &n ) const {
972 CallDynamicJavaNode &call = (CallDynamicJavaNode&)n;
973 return CallJavaNode::cmp(call);
974 }
975 #ifndef PRODUCT
976 void CallDynamicJavaNode::dump_spec(outputStream *st) const {
977 st->print("# Dynamic ");
978 CallJavaNode::dump_spec(st);
979 }
980 #endif
982 //=============================================================================
983 uint CallRuntimeNode::size_of() const { return sizeof(*this); }
984 uint CallRuntimeNode::cmp( const Node &n ) const {
985 CallRuntimeNode &call = (CallRuntimeNode&)n;
986 return CallNode::cmp(call) && !strcmp(_name,call._name);
987 }
988 #ifndef PRODUCT
989 void CallRuntimeNode::dump_spec(outputStream *st) const {
990 st->print("# ");
991 st->print("%s", _name);
992 CallNode::dump_spec(st);
993 }
994 #endif
996 //------------------------------calling_convention-----------------------------
997 void CallRuntimeNode::calling_convention( BasicType* sig_bt, VMRegPair *parm_regs, uint argcnt ) const {
998 Matcher::c_calling_convention( sig_bt, parm_regs, argcnt );
999 }
1001 //=============================================================================
1002 //------------------------------calling_convention-----------------------------
1005 //=============================================================================
1006 #ifndef PRODUCT
1007 void CallLeafNode::dump_spec(outputStream *st) const {
1008 st->print("# ");
1009 st->print("%s", _name);
1010 CallNode::dump_spec(st);
1011 }
1012 #endif
1014 //=============================================================================
1016 void SafePointNode::set_local(JVMState* jvms, uint idx, Node *c) {
1017 assert(verify_jvms(jvms), "jvms must match");
1018 int loc = jvms->locoff() + idx;
1019 if (in(loc)->is_top() && idx > 0 && !c->is_top() ) {
1020 // If current local idx is top then local idx - 1 could
1021 // be a long/double that needs to be killed since top could
1022 // represent the 2nd half ofthe long/double.
1023 uint ideal = in(loc -1)->ideal_reg();
1024 if (ideal == Op_RegD || ideal == Op_RegL) {
1025 // set other (low index) half to top
1026 set_req(loc - 1, in(loc));
1027 }
1028 }
1029 set_req(loc, c);
1030 }
1032 uint SafePointNode::size_of() const { return sizeof(*this); }
1033 uint SafePointNode::cmp( const Node &n ) const {
1034 return (&n == this); // Always fail except on self
1035 }
1037 //-------------------------set_next_exception----------------------------------
1038 void SafePointNode::set_next_exception(SafePointNode* n) {
1039 assert(n == NULL || n->Opcode() == Op_SafePoint, "correct value for next_exception");
1040 if (len() == req()) {
1041 if (n != NULL) add_prec(n);
1042 } else {
1043 set_prec(req(), n);
1044 }
1045 }
1048 //----------------------------next_exception-----------------------------------
1049 SafePointNode* SafePointNode::next_exception() const {
1050 if (len() == req()) {
1051 return NULL;
1052 } else {
1053 Node* n = in(req());
1054 assert(n == NULL || n->Opcode() == Op_SafePoint, "no other uses of prec edges");
1055 return (SafePointNode*) n;
1056 }
1057 }
1060 //------------------------------Ideal------------------------------------------
1061 // Skip over any collapsed Regions
1062 Node *SafePointNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1063 return remove_dead_region(phase, can_reshape) ? this : NULL;
1064 }
1066 //------------------------------Identity---------------------------------------
1067 // Remove obviously duplicate safepoints
1068 Node *SafePointNode::Identity( PhaseTransform *phase ) {
1070 // If you have back to back safepoints, remove one
1071 if( in(TypeFunc::Control)->is_SafePoint() )
1072 return in(TypeFunc::Control);
1074 if( in(0)->is_Proj() ) {
1075 Node *n0 = in(0)->in(0);
1076 // Check if he is a call projection (except Leaf Call)
1077 if( n0->is_Catch() ) {
1078 n0 = n0->in(0)->in(0);
1079 assert( n0->is_Call(), "expect a call here" );
1080 }
1081 if( n0->is_Call() && n0->as_Call()->guaranteed_safepoint() ) {
1082 // Useless Safepoint, so remove it
1083 return in(TypeFunc::Control);
1084 }
1085 }
1087 return this;
1088 }
1090 //------------------------------Value------------------------------------------
1091 const Type *SafePointNode::Value( PhaseTransform *phase ) const {
1092 if( phase->type(in(0)) == Type::TOP ) return Type::TOP;
1093 if( phase->eqv( in(0), this ) ) return Type::TOP; // Dead infinite loop
1094 return Type::CONTROL;
1095 }
1097 #ifndef PRODUCT
1098 void SafePointNode::dump_spec(outputStream *st) const {
1099 st->print(" SafePoint ");
1100 _replaced_nodes.dump(st);
1101 }
1102 #endif
1104 const RegMask &SafePointNode::in_RegMask(uint idx) const {
1105 if( idx < TypeFunc::Parms ) return RegMask::Empty;
1106 // Values outside the domain represent debug info
1107 return *(Compile::current()->matcher()->idealreg2debugmask[in(idx)->ideal_reg()]);
1108 }
1109 const RegMask &SafePointNode::out_RegMask() const {
1110 return RegMask::Empty;
1111 }
1114 void SafePointNode::grow_stack(JVMState* jvms, uint grow_by) {
1115 assert((int)grow_by > 0, "sanity");
1116 int monoff = jvms->monoff();
1117 int scloff = jvms->scloff();
1118 int endoff = jvms->endoff();
1119 assert(endoff == (int)req(), "no other states or debug info after me");
1120 Node* top = Compile::current()->top();
1121 for (uint i = 0; i < grow_by; i++) {
1122 ins_req(monoff, top);
1123 }
1124 jvms->set_monoff(monoff + grow_by);
1125 jvms->set_scloff(scloff + grow_by);
1126 jvms->set_endoff(endoff + grow_by);
1127 }
1129 void SafePointNode::push_monitor(const FastLockNode *lock) {
1130 // Add a LockNode, which points to both the original BoxLockNode (the
1131 // stack space for the monitor) and the Object being locked.
1132 const int MonitorEdges = 2;
1133 assert(JVMState::logMonitorEdges == exact_log2(MonitorEdges), "correct MonitorEdges");
1134 assert(req() == jvms()->endoff(), "correct sizing");
1135 int nextmon = jvms()->scloff();
1136 if (GenerateSynchronizationCode) {
1137 ins_req(nextmon, lock->box_node());
1138 ins_req(nextmon+1, lock->obj_node());
1139 } else {
1140 Node* top = Compile::current()->top();
1141 ins_req(nextmon, top);
1142 ins_req(nextmon, top);
1143 }
1144 jvms()->set_scloff(nextmon + MonitorEdges);
1145 jvms()->set_endoff(req());
1146 }
1148 void SafePointNode::pop_monitor() {
1149 // Delete last monitor from debug info
1150 debug_only(int num_before_pop = jvms()->nof_monitors());
1151 const int MonitorEdges = 2;
1152 assert(JVMState::logMonitorEdges == exact_log2(MonitorEdges), "correct MonitorEdges");
1153 int scloff = jvms()->scloff();
1154 int endoff = jvms()->endoff();
1155 int new_scloff = scloff - MonitorEdges;
1156 int new_endoff = endoff - MonitorEdges;
1157 jvms()->set_scloff(new_scloff);
1158 jvms()->set_endoff(new_endoff);
1159 while (scloff > new_scloff) del_req_ordered(--scloff);
1160 assert(jvms()->nof_monitors() == num_before_pop-1, "");
1161 }
1163 Node *SafePointNode::peek_monitor_box() const {
1164 int mon = jvms()->nof_monitors() - 1;
1165 assert(mon >= 0, "most have a monitor");
1166 return monitor_box(jvms(), mon);
1167 }
1169 Node *SafePointNode::peek_monitor_obj() const {
1170 int mon = jvms()->nof_monitors() - 1;
1171 assert(mon >= 0, "most have a monitor");
1172 return monitor_obj(jvms(), mon);
1173 }
1175 // Do we Match on this edge index or not? Match no edges
1176 uint SafePointNode::match_edge(uint idx) const {
1177 if( !needs_polling_address_input() )
1178 return 0;
1180 return (TypeFunc::Parms == idx);
1181 }
1183 //============== SafePointScalarObjectNode ==============
1185 SafePointScalarObjectNode::SafePointScalarObjectNode(const TypeOopPtr* tp,
1186 #ifdef ASSERT
1187 AllocateNode* alloc,
1188 #endif
1189 uint first_index,
1190 uint n_fields) :
1191 TypeNode(tp, 1), // 1 control input -- seems required. Get from root.
1192 #ifdef ASSERT
1193 _alloc(alloc),
1194 #endif
1195 _first_index(first_index),
1196 _n_fields(n_fields)
1197 {
1198 init_class_id(Class_SafePointScalarObject);
1199 }
1201 // Do not allow value-numbering for SafePointScalarObject node.
1202 uint SafePointScalarObjectNode::hash() const { return NO_HASH; }
1203 uint SafePointScalarObjectNode::cmp( const Node &n ) const {
1204 return (&n == this); // Always fail except on self
1205 }
1207 uint SafePointScalarObjectNode::ideal_reg() const {
1208 return 0; // No matching to machine instruction
1209 }
1211 const RegMask &SafePointScalarObjectNode::in_RegMask(uint idx) const {
1212 return *(Compile::current()->matcher()->idealreg2debugmask[in(idx)->ideal_reg()]);
1213 }
1215 const RegMask &SafePointScalarObjectNode::out_RegMask() const {
1216 return RegMask::Empty;
1217 }
1219 uint SafePointScalarObjectNode::match_edge(uint idx) const {
1220 return 0;
1221 }
1223 SafePointScalarObjectNode*
1224 SafePointScalarObjectNode::clone(Dict* sosn_map) const {
1225 void* cached = (*sosn_map)[(void*)this];
1226 if (cached != NULL) {
1227 return (SafePointScalarObjectNode*)cached;
1228 }
1229 SafePointScalarObjectNode* res = (SafePointScalarObjectNode*)Node::clone();
1230 sosn_map->Insert((void*)this, (void*)res);
1231 return res;
1232 }
1235 #ifndef PRODUCT
1236 void SafePointScalarObjectNode::dump_spec(outputStream *st) const {
1237 st->print(" # fields@[%d..%d]", first_index(),
1238 first_index() + n_fields() - 1);
1239 }
1241 #endif
1243 //=============================================================================
1244 uint AllocateNode::size_of() const { return sizeof(*this); }
1246 AllocateNode::AllocateNode(Compile* C, const TypeFunc *atype,
1247 Node *ctrl, Node *mem, Node *abio,
1248 Node *size, Node *klass_node, Node *initial_test)
1249 : CallNode(atype, NULL, TypeRawPtr::BOTTOM)
1250 {
1251 init_class_id(Class_Allocate);
1252 init_flags(Flag_is_macro);
1253 _is_scalar_replaceable = false;
1254 _is_non_escaping = false;
1255 Node *topnode = C->top();
1257 init_req( TypeFunc::Control , ctrl );
1258 init_req( TypeFunc::I_O , abio );
1259 init_req( TypeFunc::Memory , mem );
1260 init_req( TypeFunc::ReturnAdr, topnode );
1261 init_req( TypeFunc::FramePtr , topnode );
1262 init_req( AllocSize , size);
1263 init_req( KlassNode , klass_node);
1264 init_req( InitialTest , initial_test);
1265 init_req( ALength , topnode);
1266 C->add_macro_node(this);
1267 }
1269 //=============================================================================
1270 Node* AllocateArrayNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1271 if (remove_dead_region(phase, can_reshape)) return this;
1272 // Don't bother trying to transform a dead node
1273 if (in(0) && in(0)->is_top()) return NULL;
1275 const Type* type = phase->type(Ideal_length());
1276 if (type->isa_int() && type->is_int()->_hi < 0) {
1277 if (can_reshape) {
1278 PhaseIterGVN *igvn = phase->is_IterGVN();
1279 // Unreachable fall through path (negative array length),
1280 // the allocation can only throw so disconnect it.
1281 Node* proj = proj_out(TypeFunc::Control);
1282 Node* catchproj = NULL;
1283 if (proj != NULL) {
1284 for (DUIterator_Fast imax, i = proj->fast_outs(imax); i < imax; i++) {
1285 Node *cn = proj->fast_out(i);
1286 if (cn->is_Catch()) {
1287 catchproj = cn->as_Multi()->proj_out(CatchProjNode::fall_through_index);
1288 break;
1289 }
1290 }
1291 }
1292 if (catchproj != NULL && catchproj->outcnt() > 0 &&
1293 (catchproj->outcnt() > 1 ||
1294 catchproj->unique_out()->Opcode() != Op_Halt)) {
1295 assert(catchproj->is_CatchProj(), "must be a CatchProjNode");
1296 Node* nproj = catchproj->clone();
1297 igvn->register_new_node_with_optimizer(nproj);
1299 Node *frame = new (phase->C) ParmNode( phase->C->start(), TypeFunc::FramePtr );
1300 frame = phase->transform(frame);
1301 // Halt & Catch Fire
1302 Node *halt = new (phase->C) HaltNode( nproj, frame );
1303 phase->C->root()->add_req(halt);
1304 phase->transform(halt);
1306 igvn->replace_node(catchproj, phase->C->top());
1307 return this;
1308 }
1309 } else {
1310 // Can't correct it during regular GVN so register for IGVN
1311 phase->C->record_for_igvn(this);
1312 }
1313 }
1314 return NULL;
1315 }
1317 // Retrieve the length from the AllocateArrayNode. Narrow the type with a
1318 // CastII, if appropriate. If we are not allowed to create new nodes, and
1319 // a CastII is appropriate, return NULL.
1320 Node *AllocateArrayNode::make_ideal_length(const TypeOopPtr* oop_type, PhaseTransform *phase, bool allow_new_nodes) {
1321 Node *length = in(AllocateNode::ALength);
1322 assert(length != NULL, "length is not null");
1324 const TypeInt* length_type = phase->find_int_type(length);
1325 const TypeAryPtr* ary_type = oop_type->isa_aryptr();
1327 if (ary_type != NULL && length_type != NULL) {
1328 const TypeInt* narrow_length_type = ary_type->narrow_size_type(length_type);
1329 if (narrow_length_type != length_type) {
1330 // Assert one of:
1331 // - the narrow_length is 0
1332 // - the narrow_length is not wider than length
1333 assert(narrow_length_type == TypeInt::ZERO ||
1334 length_type->is_con() && narrow_length_type->is_con() &&
1335 (narrow_length_type->_hi <= length_type->_lo) ||
1336 (narrow_length_type->_hi <= length_type->_hi &&
1337 narrow_length_type->_lo >= length_type->_lo),
1338 "narrow type must be narrower than length type");
1340 // Return NULL if new nodes are not allowed
1341 if (!allow_new_nodes) return NULL;
1342 // Create a cast which is control dependent on the initialization to
1343 // propagate the fact that the array length must be positive.
1344 length = new (phase->C) CastIINode(length, narrow_length_type);
1345 length->set_req(0, initialization()->proj_out(0));
1346 }
1347 }
1349 return length;
1350 }
1352 //=============================================================================
1353 uint LockNode::size_of() const { return sizeof(*this); }
1355 // Redundant lock elimination
1356 //
1357 // There are various patterns of locking where we release and
1358 // immediately reacquire a lock in a piece of code where no operations
1359 // occur in between that would be observable. In those cases we can
1360 // skip releasing and reacquiring the lock without violating any
1361 // fairness requirements. Doing this around a loop could cause a lock
1362 // to be held for a very long time so we concentrate on non-looping
1363 // control flow. We also require that the operations are fully
1364 // redundant meaning that we don't introduce new lock operations on
1365 // some paths so to be able to eliminate it on others ala PRE. This
1366 // would probably require some more extensive graph manipulation to
1367 // guarantee that the memory edges were all handled correctly.
1368 //
1369 // Assuming p is a simple predicate which can't trap in any way and s
1370 // is a synchronized method consider this code:
1371 //
1372 // s();
1373 // if (p)
1374 // s();
1375 // else
1376 // s();
1377 // s();
1378 //
1379 // 1. The unlocks of the first call to s can be eliminated if the
1380 // locks inside the then and else branches are eliminated.
1381 //
1382 // 2. The unlocks of the then and else branches can be eliminated if
1383 // the lock of the final call to s is eliminated.
1384 //
1385 // Either of these cases subsumes the simple case of sequential control flow
1386 //
1387 // Addtionally we can eliminate versions without the else case:
1388 //
1389 // s();
1390 // if (p)
1391 // s();
1392 // s();
1393 //
1394 // 3. In this case we eliminate the unlock of the first s, the lock
1395 // and unlock in the then case and the lock in the final s.
1396 //
1397 // Note also that in all these cases the then/else pieces don't have
1398 // to be trivial as long as they begin and end with synchronization
1399 // operations.
1400 //
1401 // s();
1402 // if (p)
1403 // s();
1404 // f();
1405 // s();
1406 // s();
1407 //
1408 // The code will work properly for this case, leaving in the unlock
1409 // before the call to f and the relock after it.
1410 //
1411 // A potentially interesting case which isn't handled here is when the
1412 // locking is partially redundant.
1413 //
1414 // s();
1415 // if (p)
1416 // s();
1417 //
1418 // This could be eliminated putting unlocking on the else case and
1419 // eliminating the first unlock and the lock in the then side.
1420 // Alternatively the unlock could be moved out of the then side so it
1421 // was after the merge and the first unlock and second lock
1422 // eliminated. This might require less manipulation of the memory
1423 // state to get correct.
1424 //
1425 // Additionally we might allow work between a unlock and lock before
1426 // giving up eliminating the locks. The current code disallows any
1427 // conditional control flow between these operations. A formulation
1428 // similar to partial redundancy elimination computing the
1429 // availability of unlocking and the anticipatability of locking at a
1430 // program point would allow detection of fully redundant locking with
1431 // some amount of work in between. I'm not sure how often I really
1432 // think that would occur though. Most of the cases I've seen
1433 // indicate it's likely non-trivial work would occur in between.
1434 // There may be other more complicated constructs where we could
1435 // eliminate locking but I haven't seen any others appear as hot or
1436 // interesting.
1437 //
1438 // Locking and unlocking have a canonical form in ideal that looks
1439 // roughly like this:
1440 //
1441 // <obj>
1442 // | \\------+
1443 // | \ \
1444 // | BoxLock \
1445 // | | | \
1446 // | | \ \
1447 // | | FastLock
1448 // | | /
1449 // | | /
1450 // | | |
1451 //
1452 // Lock
1453 // |
1454 // Proj #0
1455 // |
1456 // MembarAcquire
1457 // |
1458 // Proj #0
1459 //
1460 // MembarRelease
1461 // |
1462 // Proj #0
1463 // |
1464 // Unlock
1465 // |
1466 // Proj #0
1467 //
1468 //
1469 // This code proceeds by processing Lock nodes during PhaseIterGVN
1470 // and searching back through its control for the proper code
1471 // patterns. Once it finds a set of lock and unlock operations to
1472 // eliminate they are marked as eliminatable which causes the
1473 // expansion of the Lock and Unlock macro nodes to make the operation a NOP
1474 //
1475 //=============================================================================
1477 //
1478 // Utility function to skip over uninteresting control nodes. Nodes skipped are:
1479 // - copy regions. (These may not have been optimized away yet.)
1480 // - eliminated locking nodes
1481 //
1482 static Node *next_control(Node *ctrl) {
1483 if (ctrl == NULL)
1484 return NULL;
1485 while (1) {
1486 if (ctrl->is_Region()) {
1487 RegionNode *r = ctrl->as_Region();
1488 Node *n = r->is_copy();
1489 if (n == NULL)
1490 break; // hit a region, return it
1491 else
1492 ctrl = n;
1493 } else if (ctrl->is_Proj()) {
1494 Node *in0 = ctrl->in(0);
1495 if (in0->is_AbstractLock() && in0->as_AbstractLock()->is_eliminated()) {
1496 ctrl = in0->in(0);
1497 } else {
1498 break;
1499 }
1500 } else {
1501 break; // found an interesting control
1502 }
1503 }
1504 return ctrl;
1505 }
1506 //
1507 // Given a control, see if it's the control projection of an Unlock which
1508 // operating on the same object as lock.
1509 //
1510 bool AbstractLockNode::find_matching_unlock(const Node* ctrl, LockNode* lock,
1511 GrowableArray<AbstractLockNode*> &lock_ops) {
1512 ProjNode *ctrl_proj = (ctrl->is_Proj()) ? ctrl->as_Proj() : NULL;
1513 if (ctrl_proj != NULL && ctrl_proj->_con == TypeFunc::Control) {
1514 Node *n = ctrl_proj->in(0);
1515 if (n != NULL && n->is_Unlock()) {
1516 UnlockNode *unlock = n->as_Unlock();
1517 if (lock->obj_node()->eqv_uncast(unlock->obj_node()) &&
1518 BoxLockNode::same_slot(lock->box_node(), unlock->box_node()) &&
1519 !unlock->is_eliminated()) {
1520 lock_ops.append(unlock);
1521 return true;
1522 }
1523 }
1524 }
1525 return false;
1526 }
1528 //
1529 // Find the lock matching an unlock. Returns null if a safepoint
1530 // or complicated control is encountered first.
1531 LockNode *AbstractLockNode::find_matching_lock(UnlockNode* unlock) {
1532 LockNode *lock_result = NULL;
1533 // find the matching lock, or an intervening safepoint
1534 Node *ctrl = next_control(unlock->in(0));
1535 while (1) {
1536 assert(ctrl != NULL, "invalid control graph");
1537 assert(!ctrl->is_Start(), "missing lock for unlock");
1538 if (ctrl->is_top()) break; // dead control path
1539 if (ctrl->is_Proj()) ctrl = ctrl->in(0);
1540 if (ctrl->is_SafePoint()) {
1541 break; // found a safepoint (may be the lock we are searching for)
1542 } else if (ctrl->is_Region()) {
1543 // Check for a simple diamond pattern. Punt on anything more complicated
1544 if (ctrl->req() == 3 && ctrl->in(1) != NULL && ctrl->in(2) != NULL) {
1545 Node *in1 = next_control(ctrl->in(1));
1546 Node *in2 = next_control(ctrl->in(2));
1547 if (((in1->is_IfTrue() && in2->is_IfFalse()) ||
1548 (in2->is_IfTrue() && in1->is_IfFalse())) && (in1->in(0) == in2->in(0))) {
1549 ctrl = next_control(in1->in(0)->in(0));
1550 } else {
1551 break;
1552 }
1553 } else {
1554 break;
1555 }
1556 } else {
1557 ctrl = next_control(ctrl->in(0)); // keep searching
1558 }
1559 }
1560 if (ctrl->is_Lock()) {
1561 LockNode *lock = ctrl->as_Lock();
1562 if (lock->obj_node()->eqv_uncast(unlock->obj_node()) &&
1563 BoxLockNode::same_slot(lock->box_node(), unlock->box_node())) {
1564 lock_result = lock;
1565 }
1566 }
1567 return lock_result;
1568 }
1570 // This code corresponds to case 3 above.
1572 bool AbstractLockNode::find_lock_and_unlock_through_if(Node* node, LockNode* lock,
1573 GrowableArray<AbstractLockNode*> &lock_ops) {
1574 Node* if_node = node->in(0);
1575 bool if_true = node->is_IfTrue();
1577 if (if_node->is_If() && if_node->outcnt() == 2 && (if_true || node->is_IfFalse())) {
1578 Node *lock_ctrl = next_control(if_node->in(0));
1579 if (find_matching_unlock(lock_ctrl, lock, lock_ops)) {
1580 Node* lock1_node = NULL;
1581 ProjNode* proj = if_node->as_If()->proj_out(!if_true);
1582 if (if_true) {
1583 if (proj->is_IfFalse() && proj->outcnt() == 1) {
1584 lock1_node = proj->unique_out();
1585 }
1586 } else {
1587 if (proj->is_IfTrue() && proj->outcnt() == 1) {
1588 lock1_node = proj->unique_out();
1589 }
1590 }
1591 if (lock1_node != NULL && lock1_node->is_Lock()) {
1592 LockNode *lock1 = lock1_node->as_Lock();
1593 if (lock->obj_node()->eqv_uncast(lock1->obj_node()) &&
1594 BoxLockNode::same_slot(lock->box_node(), lock1->box_node()) &&
1595 !lock1->is_eliminated()) {
1596 lock_ops.append(lock1);
1597 return true;
1598 }
1599 }
1600 }
1601 }
1603 lock_ops.trunc_to(0);
1604 return false;
1605 }
1607 bool AbstractLockNode::find_unlocks_for_region(const RegionNode* region, LockNode* lock,
1608 GrowableArray<AbstractLockNode*> &lock_ops) {
1609 // check each control merging at this point for a matching unlock.
1610 // in(0) should be self edge so skip it.
1611 for (int i = 1; i < (int)region->req(); i++) {
1612 Node *in_node = next_control(region->in(i));
1613 if (in_node != NULL) {
1614 if (find_matching_unlock(in_node, lock, lock_ops)) {
1615 // found a match so keep on checking.
1616 continue;
1617 } else if (find_lock_and_unlock_through_if(in_node, lock, lock_ops)) {
1618 continue;
1619 }
1621 // If we fall through to here then it was some kind of node we
1622 // don't understand or there wasn't a matching unlock, so give
1623 // up trying to merge locks.
1624 lock_ops.trunc_to(0);
1625 return false;
1626 }
1627 }
1628 return true;
1630 }
1632 #ifndef PRODUCT
1633 //
1634 // Create a counter which counts the number of times this lock is acquired
1635 //
1636 void AbstractLockNode::create_lock_counter(JVMState* state) {
1637 _counter = OptoRuntime::new_named_counter(state, NamedCounter::LockCounter);
1638 }
1640 void AbstractLockNode::set_eliminated_lock_counter() {
1641 if (_counter) {
1642 // Update the counter to indicate that this lock was eliminated.
1643 // The counter update code will stay around even though the
1644 // optimizer will eliminate the lock operation itself.
1645 _counter->set_tag(NamedCounter::EliminatedLockCounter);
1646 }
1647 }
1648 #endif
1650 //=============================================================================
1651 Node *LockNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1653 // perform any generic optimizations first (returns 'this' or NULL)
1654 Node *result = SafePointNode::Ideal(phase, can_reshape);
1655 if (result != NULL) return result;
1656 // Don't bother trying to transform a dead node
1657 if (in(0) && in(0)->is_top()) return NULL;
1659 // Now see if we can optimize away this lock. We don't actually
1660 // remove the locking here, we simply set the _eliminate flag which
1661 // prevents macro expansion from expanding the lock. Since we don't
1662 // modify the graph, the value returned from this function is the
1663 // one computed above.
1664 if (can_reshape && EliminateLocks && !is_non_esc_obj()) {
1665 //
1666 // If we are locking an unescaped object, the lock/unlock is unnecessary
1667 //
1668 ConnectionGraph *cgr = phase->C->congraph();
1669 if (cgr != NULL && cgr->not_global_escape(obj_node())) {
1670 assert(!is_eliminated() || is_coarsened(), "sanity");
1671 // The lock could be marked eliminated by lock coarsening
1672 // code during first IGVN before EA. Replace coarsened flag
1673 // to eliminate all associated locks/unlocks.
1674 #ifdef ASSERT
1675 this->log_lock_optimization(phase->C,"eliminate_lock_set_non_esc1");
1676 #endif
1677 this->set_non_esc_obj();
1678 return result;
1679 }
1681 //
1682 // Try lock coarsening
1683 //
1684 PhaseIterGVN* iter = phase->is_IterGVN();
1685 if (iter != NULL && !is_eliminated()) {
1687 GrowableArray<AbstractLockNode*> lock_ops;
1689 Node *ctrl = next_control(in(0));
1691 // now search back for a matching Unlock
1692 if (find_matching_unlock(ctrl, this, lock_ops)) {
1693 // found an unlock directly preceding this lock. This is the
1694 // case of single unlock directly control dependent on a
1695 // single lock which is the trivial version of case 1 or 2.
1696 } else if (ctrl->is_Region() ) {
1697 if (find_unlocks_for_region(ctrl->as_Region(), this, lock_ops)) {
1698 // found lock preceded by multiple unlocks along all paths
1699 // joining at this point which is case 3 in description above.
1700 }
1701 } else {
1702 // see if this lock comes from either half of an if and the
1703 // predecessors merges unlocks and the other half of the if
1704 // performs a lock.
1705 if (find_lock_and_unlock_through_if(ctrl, this, lock_ops)) {
1706 // found unlock splitting to an if with locks on both branches.
1707 }
1708 }
1710 if (lock_ops.length() > 0) {
1711 // add ourselves to the list of locks to be eliminated.
1712 lock_ops.append(this);
1714 #ifndef PRODUCT
1715 if (PrintEliminateLocks) {
1716 int locks = 0;
1717 int unlocks = 0;
1718 for (int i = 0; i < lock_ops.length(); i++) {
1719 AbstractLockNode* lock = lock_ops.at(i);
1720 if (lock->Opcode() == Op_Lock)
1721 locks++;
1722 else
1723 unlocks++;
1724 if (Verbose) {
1725 lock->dump(1);
1726 }
1727 }
1728 tty->print_cr("***Eliminated %d unlocks and %d locks", unlocks, locks);
1729 }
1730 #endif
1732 // for each of the identified locks, mark them
1733 // as eliminatable
1734 for (int i = 0; i < lock_ops.length(); i++) {
1735 AbstractLockNode* lock = lock_ops.at(i);
1737 // Mark it eliminated by coarsening and update any counters
1738 #ifdef ASSERT
1739 lock->log_lock_optimization(phase->C, "eliminate_lock_set_coarsened");
1740 #endif
1741 lock->set_coarsened();
1742 }
1743 } else if (ctrl->is_Region() &&
1744 iter->_worklist.member(ctrl)) {
1745 // We weren't able to find any opportunities but the region this
1746 // lock is control dependent on hasn't been processed yet so put
1747 // this lock back on the worklist so we can check again once any
1748 // region simplification has occurred.
1749 iter->_worklist.push(this);
1750 }
1751 }
1752 }
1754 return result;
1755 }
1757 //=============================================================================
1758 bool LockNode::is_nested_lock_region() {
1759 return is_nested_lock_region(NULL);
1760 }
1762 // p is used for access to compilation log; no logging if NULL
1763 bool LockNode::is_nested_lock_region(Compile * c) {
1764 BoxLockNode* box = box_node()->as_BoxLock();
1765 int stk_slot = box->stack_slot();
1766 if (stk_slot <= 0) {
1767 #ifdef ASSERT
1768 this->log_lock_optimization(c, "eliminate_lock_INLR_1");
1769 #endif
1770 return false; // External lock or it is not Box (Phi node).
1771 }
1773 // Ignore complex cases: merged locks or multiple locks.
1774 Node* obj = obj_node();
1775 LockNode* unique_lock = NULL;
1776 if (!box->is_simple_lock_region(&unique_lock, obj)) {
1777 #ifdef ASSERT
1778 this->log_lock_optimization(c, "eliminate_lock_INLR_2a");
1779 #endif
1780 return false;
1781 }
1782 if (unique_lock != this) {
1783 #ifdef ASSERT
1784 this->log_lock_optimization(c, "eliminate_lock_INLR_2b");
1785 #endif
1786 return false;
1787 }
1789 // Look for external lock for the same object.
1790 SafePointNode* sfn = this->as_SafePoint();
1791 JVMState* youngest_jvms = sfn->jvms();
1792 int max_depth = youngest_jvms->depth();
1793 for (int depth = 1; depth <= max_depth; depth++) {
1794 JVMState* jvms = youngest_jvms->of_depth(depth);
1795 int num_mon = jvms->nof_monitors();
1796 // Loop over monitors
1797 for (int idx = 0; idx < num_mon; idx++) {
1798 Node* obj_node = sfn->monitor_obj(jvms, idx);
1799 BoxLockNode* box_node = sfn->monitor_box(jvms, idx)->as_BoxLock();
1800 if ((box_node->stack_slot() < stk_slot) && obj_node->eqv_uncast(obj)) {
1801 return true;
1802 }
1803 }
1804 }
1805 #ifdef ASSERT
1806 this->log_lock_optimization(c, "eliminate_lock_INLR_3");
1807 #endif
1808 return false;
1809 }
1811 //=============================================================================
1812 uint UnlockNode::size_of() const { return sizeof(*this); }
1814 //=============================================================================
1815 Node *UnlockNode::Ideal(PhaseGVN *phase, bool can_reshape) {
1817 // perform any generic optimizations first (returns 'this' or NULL)
1818 Node *result = SafePointNode::Ideal(phase, can_reshape);
1819 if (result != NULL) return result;
1820 // Don't bother trying to transform a dead node
1821 if (in(0) && in(0)->is_top()) return NULL;
1823 // Now see if we can optimize away this unlock. We don't actually
1824 // remove the unlocking here, we simply set the _eliminate flag which
1825 // prevents macro expansion from expanding the unlock. Since we don't
1826 // modify the graph, the value returned from this function is the
1827 // one computed above.
1828 // Escape state is defined after Parse phase.
1829 if (can_reshape && EliminateLocks && !is_non_esc_obj()) {
1830 //
1831 // If we are unlocking an unescaped object, the lock/unlock is unnecessary.
1832 //
1833 ConnectionGraph *cgr = phase->C->congraph();
1834 if (cgr != NULL && cgr->not_global_escape(obj_node())) {
1835 assert(!is_eliminated() || is_coarsened(), "sanity");
1836 // The lock could be marked eliminated by lock coarsening
1837 // code during first IGVN before EA. Replace coarsened flag
1838 // to eliminate all associated locks/unlocks.
1839 #ifdef ASSERT
1840 this->log_lock_optimization(phase->C, "eliminate_lock_set_non_esc2");
1841 #endif
1842 this->set_non_esc_obj();
1843 }
1844 }
1845 return result;
1846 }
1848 const char * AbstractLockNode::kind_as_string() const {
1849 return is_coarsened() ? "coarsened" :
1850 is_nested() ? "nested" :
1851 is_non_esc_obj() ? "non_escaping" :
1852 "?";
1853 }
1855 void AbstractLockNode::log_lock_optimization(Compile *C, const char * tag) const {
1856 if (C == NULL) {
1857 return;
1858 }
1859 CompileLog* log = C->log();
1860 if (log != NULL) {
1861 log->begin_head("%s lock='%d' compile_id='%d' class_id='%s' kind='%s'",
1862 tag, is_Lock(), C->compile_id(),
1863 is_Unlock() ? "unlock" : is_Lock() ? "lock" : "?",
1864 kind_as_string());
1865 log->stamp();
1866 log->end_head();
1867 JVMState* p = is_Unlock() ? (as_Unlock()->dbg_jvms()) : jvms();
1868 while (p != NULL) {
1869 log->elem("jvms bci='%d' method='%d'", p->bci(), log->identify(p->method()));
1870 p = p->caller();
1871 }
1872 log->tail(tag);
1873 }
1874 }