1 /*
2 * Copyright (c) 2005, 2025, 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 "compiler/compileLog.hpp"
26 #include "gc/shared/collectedHeap.inline.hpp"
27 #include "gc/shared/tlab_globals.hpp"
28 #include "libadt/vectset.hpp"
29 #include "memory/universe.hpp"
30 #include "opto/addnode.hpp"
31 #include "opto/arraycopynode.hpp"
32 #include "opto/callnode.hpp"
33 #include "opto/castnode.hpp"
34 #include "opto/cfgnode.hpp"
35 #include "opto/compile.hpp"
36 #include "opto/convertnode.hpp"
37 #include "opto/graphKit.hpp"
38 #include "opto/intrinsicnode.hpp"
39 #include "opto/locknode.hpp"
40 #include "opto/loopnode.hpp"
41 #include "opto/macro.hpp"
42 #include "opto/memnode.hpp"
43 #include "opto/narrowptrnode.hpp"
44 #include "opto/node.hpp"
45 #include "opto/opaquenode.hpp"
46 #include "opto/phaseX.hpp"
47 #include "opto/rootnode.hpp"
48 #include "opto/runtime.hpp"
49 #include "opto/subnode.hpp"
50 #include "opto/subtypenode.hpp"
51 #include "opto/type.hpp"
52 #include "prims/jvmtiExport.hpp"
53 #include "runtime/continuation.hpp"
54 #include "runtime/sharedRuntime.hpp"
55 #include "utilities/macros.hpp"
56 #include "utilities/powerOfTwo.hpp"
57 #if INCLUDE_G1GC
58 #include "gc/g1/g1ThreadLocalData.hpp"
59 #endif // INCLUDE_G1GC
60
61
62 //
63 // Replace any references to "oldref" in inputs to "use" with "newref".
64 // Returns the number of replacements made.
65 //
66 int PhaseMacroExpand::replace_input(Node *use, Node *oldref, Node *newref) {
67 int nreplacements = 0;
68 uint req = use->req();
69 for (uint j = 0; j < use->len(); j++) {
70 Node *uin = use->in(j);
71 if (uin == oldref) {
72 if (j < req)
73 use->set_req(j, newref);
74 else
75 use->set_prec(j, newref);
76 nreplacements++;
77 } else if (j >= req && uin == nullptr) {
78 break;
79 }
80 }
81 return nreplacements;
82 }
83
84 void PhaseMacroExpand::migrate_outs(Node *old, Node *target) {
85 assert(old != nullptr, "sanity");
86 for (DUIterator_Fast imax, i = old->fast_outs(imax); i < imax; i++) {
87 Node* use = old->fast_out(i);
88 _igvn.rehash_node_delayed(use);
89 imax -= replace_input(use, old, target);
90 // back up iterator
91 --i;
92 }
93 assert(old->outcnt() == 0, "all uses must be deleted");
94 }
95
96 Node* PhaseMacroExpand::opt_bits_test(Node* ctrl, Node* region, int edge, Node* word) {
97 Node* cmp = word;
98 Node* bol = transform_later(new BoolNode(cmp, BoolTest::ne));
99 IfNode* iff = new IfNode( ctrl, bol, PROB_MIN, COUNT_UNKNOWN );
100 transform_later(iff);
101
102 // Fast path taken.
103 Node *fast_taken = transform_later(new IfFalseNode(iff));
104
105 // Fast path not-taken, i.e. slow path
106 Node *slow_taken = transform_later(new IfTrueNode(iff));
107
108 region->init_req(edge, fast_taken); // Capture fast-control
109 return slow_taken;
110 }
111
112 //--------------------copy_predefined_input_for_runtime_call--------------------
113 void PhaseMacroExpand::copy_predefined_input_for_runtime_call(Node * ctrl, CallNode* oldcall, CallNode* call) {
114 // Set fixed predefined input arguments
115 call->init_req( TypeFunc::Control, ctrl );
116 call->init_req( TypeFunc::I_O , oldcall->in( TypeFunc::I_O) );
117 call->init_req( TypeFunc::Memory , oldcall->in( TypeFunc::Memory ) ); // ?????
118 call->init_req( TypeFunc::ReturnAdr, oldcall->in( TypeFunc::ReturnAdr ) );
119 call->init_req( TypeFunc::FramePtr, oldcall->in( TypeFunc::FramePtr ) );
120 }
121
122 //------------------------------make_slow_call---------------------------------
123 CallNode* PhaseMacroExpand::make_slow_call(CallNode *oldcall, const TypeFunc* slow_call_type,
124 address slow_call, const char* leaf_name, Node* slow_path,
125 Node* parm0, Node* parm1, Node* parm2) {
126
127 // Slow-path call
128 CallNode *call = leaf_name
129 ? (CallNode*)new CallLeafNode ( slow_call_type, slow_call, leaf_name, TypeRawPtr::BOTTOM )
130 : (CallNode*)new CallStaticJavaNode( slow_call_type, slow_call, OptoRuntime::stub_name(slow_call), TypeRawPtr::BOTTOM );
131
132 // Slow path call has no side-effects, uses few values
133 copy_predefined_input_for_runtime_call(slow_path, oldcall, call );
134 if (parm0 != nullptr) call->init_req(TypeFunc::Parms+0, parm0);
135 if (parm1 != nullptr) call->init_req(TypeFunc::Parms+1, parm1);
136 if (parm2 != nullptr) call->init_req(TypeFunc::Parms+2, parm2);
137 call->copy_call_debug_info(&_igvn, oldcall);
138 call->set_cnt(PROB_UNLIKELY_MAG(4)); // Same effect as RC_UNCOMMON.
139 _igvn.replace_node(oldcall, call);
140 transform_later(call);
141
142 return call;
143 }
144
145 void PhaseMacroExpand::eliminate_gc_barrier(Node* p2x) {
146 BarrierSetC2 *bs = BarrierSet::barrier_set()->barrier_set_c2();
147 bs->eliminate_gc_barrier(this, p2x);
148 #ifndef PRODUCT
149 if (PrintOptoStatistics) {
150 Atomic::inc(&PhaseMacroExpand::_GC_barriers_removed_counter);
151 }
152 #endif
153 }
154
155 // Search for a memory operation for the specified memory slice.
156 static Node *scan_mem_chain(Node *mem, int alias_idx, int offset, Node *start_mem, Node *alloc, PhaseGVN *phase) {
157 Node *orig_mem = mem;
158 Node *alloc_mem = alloc->as_Allocate()->proj_out_or_null(TypeFunc::Memory, /*io_use:*/false);
159 assert(alloc_mem != nullptr, "Allocation without a memory projection.");
160 const TypeOopPtr *tinst = phase->C->get_adr_type(alias_idx)->isa_oopptr();
161 while (true) {
162 if (mem == alloc_mem || mem == start_mem ) {
163 return mem; // hit one of our sentinels
164 } else if (mem->is_MergeMem()) {
165 mem = mem->as_MergeMem()->memory_at(alias_idx);
166 } else if (mem->is_Proj() && mem->as_Proj()->_con == TypeFunc::Memory) {
167 Node *in = mem->in(0);
168 // we can safely skip over safepoints, calls, locks and membars because we
169 // already know that the object is safe to eliminate.
170 if (in->is_Initialize() && in->as_Initialize()->allocation() == alloc) {
171 return in;
172 } else if (in->is_Call()) {
173 CallNode *call = in->as_Call();
174 if (call->may_modify(tinst, phase)) {
175 assert(call->is_ArrayCopy(), "ArrayCopy is the only call node that doesn't make allocation escape");
176 if (call->as_ArrayCopy()->modifies(offset, offset, phase, false)) {
177 return in;
178 }
179 }
180 mem = in->in(TypeFunc::Memory);
181 } else if (in->is_MemBar()) {
182 ArrayCopyNode* ac = nullptr;
183 if (ArrayCopyNode::may_modify(tinst, in->as_MemBar(), phase, ac)) {
184 if (ac != nullptr) {
185 assert(ac->is_clonebasic(), "Only basic clone is a non escaping clone");
186 return ac;
187 }
188 }
189 mem = in->in(TypeFunc::Memory);
190 } else {
191 #ifdef ASSERT
192 in->dump();
193 mem->dump();
194 assert(false, "unexpected projection");
195 #endif
196 }
197 } else if (mem->is_Store()) {
198 const TypePtr* atype = mem->as_Store()->adr_type();
199 int adr_idx = phase->C->get_alias_index(atype);
200 if (adr_idx == alias_idx) {
201 assert(atype->isa_oopptr(), "address type must be oopptr");
202 int adr_offset = atype->offset();
203 uint adr_iid = atype->is_oopptr()->instance_id();
204 // Array elements references have the same alias_idx
205 // but different offset and different instance_id.
206 if (adr_offset == offset && adr_iid == alloc->_idx) {
207 return mem;
208 }
209 } else {
210 assert(adr_idx == Compile::AliasIdxRaw, "address must match or be raw");
211 }
212 mem = mem->in(MemNode::Memory);
213 } else if (mem->is_ClearArray()) {
214 if (!ClearArrayNode::step_through(&mem, alloc->_idx, phase)) {
215 // Can not bypass initialization of the instance
216 // we are looking.
217 DEBUG_ONLY(intptr_t offset;)
218 assert(alloc == AllocateNode::Ideal_allocation(mem->in(3), phase, offset), "sanity");
219 InitializeNode* init = alloc->as_Allocate()->initialization();
220 // We are looking for stored value, return Initialize node
221 // or memory edge from Allocate node.
222 if (init != nullptr) {
223 return init;
224 } else {
225 return alloc->in(TypeFunc::Memory); // It will produce zero value (see callers).
226 }
227 }
228 // Otherwise skip it (the call updated 'mem' value).
229 } else if (mem->Opcode() == Op_SCMemProj) {
230 mem = mem->in(0);
231 Node* adr = nullptr;
232 if (mem->is_LoadStore()) {
233 adr = mem->in(MemNode::Address);
234 } else {
235 assert(mem->Opcode() == Op_EncodeISOArray ||
236 mem->Opcode() == Op_StrCompressedCopy, "sanity");
237 adr = mem->in(3); // Destination array
238 }
239 const TypePtr* atype = adr->bottom_type()->is_ptr();
240 int adr_idx = phase->C->get_alias_index(atype);
241 if (adr_idx == alias_idx) {
242 DEBUG_ONLY(mem->dump();)
243 assert(false, "Object is not scalar replaceable if a LoadStore node accesses its field");
244 return nullptr;
245 }
246 mem = mem->in(MemNode::Memory);
247 } else if (mem->Opcode() == Op_StrInflatedCopy) {
248 Node* adr = mem->in(3); // Destination array
249 const TypePtr* atype = adr->bottom_type()->is_ptr();
250 int adr_idx = phase->C->get_alias_index(atype);
251 if (adr_idx == alias_idx) {
252 DEBUG_ONLY(mem->dump();)
253 assert(false, "Object is not scalar replaceable if a StrInflatedCopy node accesses its field");
254 return nullptr;
255 }
256 mem = mem->in(MemNode::Memory);
257 } else {
258 return mem;
259 }
260 assert(mem != orig_mem, "dead memory loop");
261 }
262 }
263
264 // Generate loads from source of the arraycopy for fields of
265 // destination needed at a deoptimization point
266 Node* PhaseMacroExpand::make_arraycopy_load(ArrayCopyNode* ac, intptr_t offset, Node* ctl, Node* mem, BasicType ft, const Type *ftype, AllocateNode *alloc) {
267 BasicType bt = ft;
268 const Type *type = ftype;
269 if (ft == T_NARROWOOP) {
270 bt = T_OBJECT;
271 type = ftype->make_oopptr();
272 }
273 Node* res = nullptr;
274 if (ac->is_clonebasic()) {
275 assert(ac->in(ArrayCopyNode::Src) != ac->in(ArrayCopyNode::Dest), "clone source equals destination");
276 Node* base = ac->in(ArrayCopyNode::Src);
277 Node* adr = _igvn.transform(new AddPNode(base, base, _igvn.MakeConX(offset)));
278 const TypePtr* adr_type = _igvn.type(base)->is_ptr()->add_offset(offset);
279 MergeMemNode* mergemen = _igvn.transform(MergeMemNode::make(mem))->as_MergeMem();
280 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
281 res = ArrayCopyNode::load(bs, &_igvn, ctl, mergemen, adr, adr_type, type, bt);
282 } else {
283 if (ac->modifies(offset, offset, &_igvn, true)) {
284 assert(ac->in(ArrayCopyNode::Dest) == alloc->result_cast(), "arraycopy destination should be allocation's result");
285 uint shift = exact_log2(type2aelembytes(bt));
286 Node* src_pos = ac->in(ArrayCopyNode::SrcPos);
287 Node* dest_pos = ac->in(ArrayCopyNode::DestPos);
288 const TypeInt* src_pos_t = _igvn.type(src_pos)->is_int();
289 const TypeInt* dest_pos_t = _igvn.type(dest_pos)->is_int();
290
291 Node* adr = nullptr;
292 const TypePtr* adr_type = nullptr;
293 if (src_pos_t->is_con() && dest_pos_t->is_con()) {
294 intptr_t off = ((src_pos_t->get_con() - dest_pos_t->get_con()) << shift) + offset;
295 Node* base = ac->in(ArrayCopyNode::Src);
296 adr = _igvn.transform(new AddPNode(base, base, _igvn.MakeConX(off)));
297 adr_type = _igvn.type(base)->is_ptr()->add_offset(off);
298 if (ac->in(ArrayCopyNode::Src) == ac->in(ArrayCopyNode::Dest)) {
299 // Don't emit a new load from src if src == dst but try to get the value from memory instead
300 return value_from_mem(ac->in(TypeFunc::Memory), ctl, ft, ftype, adr_type->isa_oopptr(), alloc);
301 }
302 } else {
303 Node* diff = _igvn.transform(new SubINode(ac->in(ArrayCopyNode::SrcPos), ac->in(ArrayCopyNode::DestPos)));
304 #ifdef _LP64
305 diff = _igvn.transform(new ConvI2LNode(diff));
306 #endif
307 diff = _igvn.transform(new LShiftXNode(diff, _igvn.intcon(shift)));
308
309 Node* off = _igvn.transform(new AddXNode(_igvn.MakeConX(offset), diff));
310 Node* base = ac->in(ArrayCopyNode::Src);
311 adr = _igvn.transform(new AddPNode(base, base, off));
312 adr_type = _igvn.type(base)->is_ptr()->add_offset(Type::OffsetBot);
313 if (ac->in(ArrayCopyNode::Src) == ac->in(ArrayCopyNode::Dest)) {
314 // Non constant offset in the array: we can't statically
315 // determine the value
316 return nullptr;
317 }
318 }
319 MergeMemNode* mergemen = _igvn.transform(MergeMemNode::make(mem))->as_MergeMem();
320 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
321 res = ArrayCopyNode::load(bs, &_igvn, ctl, mergemen, adr, adr_type, type, bt);
322 }
323 }
324 if (res != nullptr) {
325 if (ftype->isa_narrowoop()) {
326 // PhaseMacroExpand::scalar_replacement adds DecodeN nodes
327 res = _igvn.transform(new EncodePNode(res, ftype));
328 }
329 return res;
330 }
331 return nullptr;
332 }
333
334 //
335 // Given a Memory Phi, compute a value Phi containing the values from stores
336 // on the input paths.
337 // Note: this function is recursive, its depth is limited by the "level" argument
338 // Returns the computed Phi, or null if it cannot compute it.
339 Node *PhaseMacroExpand::value_from_mem_phi(Node *mem, BasicType ft, const Type *phi_type, const TypeOopPtr *adr_t, AllocateNode *alloc, Node_Stack *value_phis, int level) {
340 assert(mem->is_Phi(), "sanity");
341 int alias_idx = C->get_alias_index(adr_t);
342 int offset = adr_t->offset();
343 int instance_id = adr_t->instance_id();
344
345 // Check if an appropriate value phi already exists.
346 Node* region = mem->in(0);
347 for (DUIterator_Fast kmax, k = region->fast_outs(kmax); k < kmax; k++) {
348 Node* phi = region->fast_out(k);
349 if (phi->is_Phi() && phi != mem &&
350 phi->as_Phi()->is_same_inst_field(phi_type, (int)mem->_idx, instance_id, alias_idx, offset)) {
351 return phi;
352 }
353 }
354 // Check if an appropriate new value phi already exists.
355 Node* new_phi = value_phis->find(mem->_idx);
356 if (new_phi != nullptr)
357 return new_phi;
358
359 if (level <= 0) {
360 return nullptr; // Give up: phi tree too deep
361 }
362 Node *start_mem = C->start()->proj_out_or_null(TypeFunc::Memory);
363 Node *alloc_mem = alloc->proj_out_or_null(TypeFunc::Memory, /*io_use:*/false);
364 assert(alloc_mem != nullptr, "Allocation without a memory projection.");
365
366 uint length = mem->req();
367 GrowableArray <Node *> values(length, length, nullptr);
368
369 // create a new Phi for the value
370 PhiNode *phi = new PhiNode(mem->in(0), phi_type, nullptr, mem->_idx, instance_id, alias_idx, offset);
371 transform_later(phi);
372 value_phis->push(phi, mem->_idx);
373
374 for (uint j = 1; j < length; j++) {
375 Node *in = mem->in(j);
376 if (in == nullptr || in->is_top()) {
377 values.at_put(j, in);
378 } else {
379 Node *val = scan_mem_chain(in, alias_idx, offset, start_mem, alloc, &_igvn);
380 if (val == start_mem || val == alloc_mem) {
381 // hit a sentinel, return appropriate 0 value
382 values.at_put(j, _igvn.zerocon(ft));
383 continue;
384 }
385 if (val->is_Initialize()) {
386 val = val->as_Initialize()->find_captured_store(offset, type2aelembytes(ft), &_igvn);
387 }
388 if (val == nullptr) {
389 return nullptr; // can't find a value on this path
390 }
391 if (val == mem) {
392 values.at_put(j, mem);
393 } else if (val->is_Store()) {
394 Node* n = val->in(MemNode::ValueIn);
395 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
396 n = bs->step_over_gc_barrier(n);
397 if (is_subword_type(ft)) {
398 n = Compile::narrow_value(ft, n, phi_type, &_igvn, true);
399 }
400 values.at_put(j, n);
401 } else if(val->is_Proj() && val->in(0) == alloc) {
402 values.at_put(j, _igvn.zerocon(ft));
403 } else if (val->is_Phi()) {
404 val = value_from_mem_phi(val, ft, phi_type, adr_t, alloc, value_phis, level-1);
405 if (val == nullptr) {
406 return nullptr;
407 }
408 values.at_put(j, val);
409 } else if (val->Opcode() == Op_SCMemProj) {
410 assert(val->in(0)->is_LoadStore() ||
411 val->in(0)->Opcode() == Op_EncodeISOArray ||
412 val->in(0)->Opcode() == Op_StrCompressedCopy, "sanity");
413 assert(false, "Object is not scalar replaceable if a LoadStore node accesses its field");
414 return nullptr;
415 } else if (val->is_ArrayCopy()) {
416 Node* res = make_arraycopy_load(val->as_ArrayCopy(), offset, val->in(0), val->in(TypeFunc::Memory), ft, phi_type, alloc);
417 if (res == nullptr) {
418 return nullptr;
419 }
420 values.at_put(j, res);
421 } else if (val->is_top()) {
422 // This indicates that this path into the phi is dead. Top will eventually also propagate into the Region.
423 // IGVN will clean this up later.
424 values.at_put(j, val);
425 } else {
426 DEBUG_ONLY( val->dump(); )
427 assert(false, "unknown node on this path");
428 return nullptr; // unknown node on this path
429 }
430 }
431 }
432 // Set Phi's inputs
433 for (uint j = 1; j < length; j++) {
434 if (values.at(j) == mem) {
435 phi->init_req(j, phi);
436 } else {
437 phi->init_req(j, values.at(j));
438 }
439 }
440 return phi;
441 }
442
443 // Search the last value stored into the object's field.
444 Node *PhaseMacroExpand::value_from_mem(Node *sfpt_mem, Node *sfpt_ctl, BasicType ft, const Type *ftype, const TypeOopPtr *adr_t, AllocateNode *alloc) {
445 assert(adr_t->is_known_instance_field(), "instance required");
446 int instance_id = adr_t->instance_id();
447 assert((uint)instance_id == alloc->_idx, "wrong allocation");
448
449 int alias_idx = C->get_alias_index(adr_t);
450 int offset = adr_t->offset();
451 Node *start_mem = C->start()->proj_out_or_null(TypeFunc::Memory);
452 Node *alloc_ctrl = alloc->in(TypeFunc::Control);
453 Node *alloc_mem = alloc->proj_out_or_null(TypeFunc::Memory, /*io_use:*/false);
454 assert(alloc_mem != nullptr, "Allocation without a memory projection.");
455 VectorSet visited;
456
457 bool done = sfpt_mem == alloc_mem;
458 Node *mem = sfpt_mem;
459 while (!done) {
460 if (visited.test_set(mem->_idx)) {
461 return nullptr; // found a loop, give up
462 }
463 mem = scan_mem_chain(mem, alias_idx, offset, start_mem, alloc, &_igvn);
464 if (mem == start_mem || mem == alloc_mem) {
465 done = true; // hit a sentinel, return appropriate 0 value
466 } else if (mem->is_Initialize()) {
467 mem = mem->as_Initialize()->find_captured_store(offset, type2aelembytes(ft), &_igvn);
468 if (mem == nullptr) {
469 done = true; // Something go wrong.
470 } else if (mem->is_Store()) {
471 const TypePtr* atype = mem->as_Store()->adr_type();
472 assert(C->get_alias_index(atype) == Compile::AliasIdxRaw, "store is correct memory slice");
473 done = true;
474 }
475 } else if (mem->is_Store()) {
476 const TypeOopPtr* atype = mem->as_Store()->adr_type()->isa_oopptr();
477 assert(atype != nullptr, "address type must be oopptr");
478 assert(C->get_alias_index(atype) == alias_idx &&
479 atype->is_known_instance_field() && atype->offset() == offset &&
480 atype->instance_id() == instance_id, "store is correct memory slice");
481 done = true;
482 } else if (mem->is_Phi()) {
483 // try to find a phi's unique input
484 Node *unique_input = nullptr;
485 Node *top = C->top();
486 for (uint i = 1; i < mem->req(); i++) {
487 Node *n = scan_mem_chain(mem->in(i), alias_idx, offset, start_mem, alloc, &_igvn);
488 if (n == nullptr || n == top || n == mem) {
489 continue;
490 } else if (unique_input == nullptr) {
491 unique_input = n;
492 } else if (unique_input != n) {
493 unique_input = top;
494 break;
495 }
496 }
497 if (unique_input != nullptr && unique_input != top) {
498 mem = unique_input;
499 } else {
500 done = true;
501 }
502 } else if (mem->is_ArrayCopy()) {
503 done = true;
504 } else {
505 DEBUG_ONLY( mem->dump(); )
506 assert(false, "unexpected node");
507 }
508 }
509 if (mem != nullptr) {
510 if (mem == start_mem || mem == alloc_mem) {
511 // hit a sentinel, return appropriate 0 value
512 return _igvn.zerocon(ft);
513 } else if (mem->is_Store()) {
514 Node* n = mem->in(MemNode::ValueIn);
515 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
516 n = bs->step_over_gc_barrier(n);
517 return n;
518 } else if (mem->is_Phi()) {
519 // attempt to produce a Phi reflecting the values on the input paths of the Phi
520 Node_Stack value_phis(8);
521 Node* phi = value_from_mem_phi(mem, ft, ftype, adr_t, alloc, &value_phis, ValueSearchLimit);
522 if (phi != nullptr) {
523 return phi;
524 } else {
525 // Kill all new Phis
526 while(value_phis.is_nonempty()) {
527 Node* n = value_phis.node();
528 _igvn.replace_node(n, C->top());
529 value_phis.pop();
530 }
531 }
532 } else if (mem->is_ArrayCopy()) {
533 Node* ctl = mem->in(0);
534 Node* m = mem->in(TypeFunc::Memory);
535 if (sfpt_ctl->is_Proj() && sfpt_ctl->as_Proj()->is_uncommon_trap_proj()) {
536 // pin the loads in the uncommon trap path
537 ctl = sfpt_ctl;
538 m = sfpt_mem;
539 }
540 return make_arraycopy_load(mem->as_ArrayCopy(), offset, ctl, m, ft, ftype, alloc);
541 }
542 }
543 // Something go wrong.
544 return nullptr;
545 }
546
547 // Check the possibility of scalar replacement.
548 bool PhaseMacroExpand::can_eliminate_allocation(PhaseIterGVN* igvn, AllocateNode *alloc, GrowableArray <SafePointNode *>* safepoints) {
549 // Scan the uses of the allocation to check for anything that would
550 // prevent us from eliminating it.
551 NOT_PRODUCT( const char* fail_eliminate = nullptr; )
552 DEBUG_ONLY( Node* disq_node = nullptr; )
553 bool can_eliminate = true;
554 bool reduce_merge_precheck = (safepoints == nullptr);
555
556 Node* res = alloc->result_cast();
557 const TypeOopPtr* res_type = nullptr;
558 if (res == nullptr) {
559 // All users were eliminated.
560 } else if (!res->is_CheckCastPP()) {
561 NOT_PRODUCT(fail_eliminate = "Allocation does not have unique CheckCastPP";)
562 can_eliminate = false;
563 } else {
564 res_type = igvn->type(res)->isa_oopptr();
565 if (res_type == nullptr) {
566 NOT_PRODUCT(fail_eliminate = "Neither instance or array allocation";)
567 can_eliminate = false;
568 } else if (!res_type->klass_is_exact()) {
569 NOT_PRODUCT(fail_eliminate = "Not an exact type.";)
570 can_eliminate = false;
571 } else if (res_type->isa_aryptr()) {
572 int length = alloc->in(AllocateNode::ALength)->find_int_con(-1);
573 if (length < 0) {
574 NOT_PRODUCT(fail_eliminate = "Array's size is not constant";)
575 can_eliminate = false;
576 }
577 }
578 }
579
580 if (can_eliminate && res != nullptr) {
581 BarrierSetC2 *bs = BarrierSet::barrier_set()->barrier_set_c2();
582 for (DUIterator_Fast jmax, j = res->fast_outs(jmax);
583 j < jmax && can_eliminate; j++) {
584 Node* use = res->fast_out(j);
585
586 if (use->is_AddP()) {
587 const TypePtr* addp_type = igvn->type(use)->is_ptr();
588 int offset = addp_type->offset();
589
590 if (offset == Type::OffsetTop || offset == Type::OffsetBot) {
591 NOT_PRODUCT(fail_eliminate = "Undefined field reference";)
592 can_eliminate = false;
593 break;
594 }
595 for (DUIterator_Fast kmax, k = use->fast_outs(kmax);
596 k < kmax && can_eliminate; k++) {
597 Node* n = use->fast_out(k);
598 if (!n->is_Store() && n->Opcode() != Op_CastP2X && !bs->is_gc_pre_barrier_node(n) && !reduce_merge_precheck) {
599 DEBUG_ONLY(disq_node = n;)
600 if (n->is_Load() || n->is_LoadStore()) {
601 NOT_PRODUCT(fail_eliminate = "Field load";)
602 } else {
603 NOT_PRODUCT(fail_eliminate = "Not store field reference";)
604 }
605 can_eliminate = false;
606 }
607 }
608 } else if (use->is_ArrayCopy() &&
609 (use->as_ArrayCopy()->is_clonebasic() ||
610 use->as_ArrayCopy()->is_arraycopy_validated() ||
611 use->as_ArrayCopy()->is_copyof_validated() ||
612 use->as_ArrayCopy()->is_copyofrange_validated()) &&
613 use->in(ArrayCopyNode::Dest) == res) {
614 // ok to eliminate
615 } else if (use->is_SafePoint()) {
616 SafePointNode* sfpt = use->as_SafePoint();
617 if (sfpt->is_Call() && sfpt->as_Call()->has_non_debug_use(res)) {
618 // Object is passed as argument.
619 DEBUG_ONLY(disq_node = use;)
620 NOT_PRODUCT(fail_eliminate = "Object is passed as argument";)
621 can_eliminate = false;
622 }
623 Node* sfptMem = sfpt->memory();
624 if (sfptMem == nullptr || sfptMem->is_top()) {
625 DEBUG_ONLY(disq_node = use;)
626 NOT_PRODUCT(fail_eliminate = "null or TOP memory";)
627 can_eliminate = false;
628 } else if (!reduce_merge_precheck) {
629 safepoints->append_if_missing(sfpt);
630 }
631 } else if (reduce_merge_precheck &&
632 (use->is_Phi() || use->is_EncodeP() ||
633 use->Opcode() == Op_MemBarRelease ||
634 (UseStoreStoreForCtor && use->Opcode() == Op_MemBarStoreStore))) {
635 // Nothing to do
636 } else if (use->Opcode() != Op_CastP2X) { // CastP2X is used by card mark
637 if (use->is_Phi()) {
638 if (use->outcnt() == 1 && use->unique_out()->Opcode() == Op_Return) {
639 NOT_PRODUCT(fail_eliminate = "Object is return value";)
640 } else {
641 NOT_PRODUCT(fail_eliminate = "Object is referenced by Phi";)
642 }
643 DEBUG_ONLY(disq_node = use;)
644 } else {
645 if (use->Opcode() == Op_Return) {
646 NOT_PRODUCT(fail_eliminate = "Object is return value";)
647 } else {
648 NOT_PRODUCT(fail_eliminate = "Object is referenced by node";)
649 }
650 DEBUG_ONLY(disq_node = use;)
651 }
652 can_eliminate = false;
653 }
654 }
655 }
656
657 #ifndef PRODUCT
658 if (PrintEliminateAllocations && safepoints != nullptr) {
659 if (can_eliminate) {
660 tty->print("Scalar ");
661 if (res == nullptr)
662 alloc->dump();
663 else
664 res->dump();
665 } else if (alloc->_is_scalar_replaceable) {
666 tty->print("NotScalar (%s)", fail_eliminate);
667 if (res == nullptr)
668 alloc->dump();
669 else
670 res->dump();
671 #ifdef ASSERT
672 if (disq_node != nullptr) {
673 tty->print(" >>>> ");
674 disq_node->dump();
675 }
676 #endif /*ASSERT*/
677 }
678 }
679
680 if (TraceReduceAllocationMerges && !can_eliminate && reduce_merge_precheck) {
681 tty->print_cr("\tCan't eliminate allocation because '%s': ", fail_eliminate != nullptr ? fail_eliminate : "");
682 DEBUG_ONLY(if (disq_node != nullptr) disq_node->dump();)
683 }
684 #endif
685 return can_eliminate;
686 }
687
688 void PhaseMacroExpand::undo_previous_scalarizations(GrowableArray <SafePointNode *> safepoints_done, AllocateNode* alloc) {
689 Node* res = alloc->result_cast();
690 int nfields = 0;
691 assert(res == nullptr || res->is_CheckCastPP(), "unexpected AllocateNode result");
692
693 if (res != nullptr) {
694 const TypeOopPtr* res_type = _igvn.type(res)->isa_oopptr();
695
696 if (res_type->isa_instptr()) {
697 // find the fields of the class which will be needed for safepoint debug information
698 ciInstanceKlass* iklass = res_type->is_instptr()->instance_klass();
699 nfields = iklass->nof_nonstatic_fields();
700 } else {
701 // find the array's elements which will be needed for safepoint debug information
702 nfields = alloc->in(AllocateNode::ALength)->find_int_con(-1);
703 assert(nfields >= 0, "must be an array klass.");
704 }
705 }
706
707 // rollback processed safepoints
708 while (safepoints_done.length() > 0) {
709 SafePointNode* sfpt_done = safepoints_done.pop();
710 // remove any extra entries we added to the safepoint
711 uint last = sfpt_done->req() - 1;
712 for (int k = 0; k < nfields; k++) {
713 sfpt_done->del_req(last--);
714 }
715 JVMState *jvms = sfpt_done->jvms();
716 jvms->set_endoff(sfpt_done->req());
717 // Now make a pass over the debug information replacing any references
718 // to SafePointScalarObjectNode with the allocated object.
719 int start = jvms->debug_start();
720 int end = jvms->debug_end();
721 for (int i = start; i < end; i++) {
722 if (sfpt_done->in(i)->is_SafePointScalarObject()) {
723 SafePointScalarObjectNode* scobj = sfpt_done->in(i)->as_SafePointScalarObject();
724 if (scobj->first_index(jvms) == sfpt_done->req() &&
725 scobj->n_fields() == (uint)nfields) {
726 assert(scobj->alloc() == alloc, "sanity");
727 sfpt_done->set_req(i, res);
728 }
729 }
730 }
731 _igvn._worklist.push(sfpt_done);
732 }
733 }
734
735 SafePointScalarObjectNode* PhaseMacroExpand::create_scalarized_object_description(AllocateNode *alloc, SafePointNode* sfpt) {
736 // Fields of scalar objs are referenced only at the end
737 // of regular debuginfo at the last (youngest) JVMS.
738 // Record relative start index.
739 ciInstanceKlass* iklass = nullptr;
740 BasicType basic_elem_type = T_ILLEGAL;
741 const Type* field_type = nullptr;
742 const TypeOopPtr* res_type = nullptr;
743 int nfields = 0;
744 int array_base = 0;
745 int element_size = 0;
746 uint first_ind = (sfpt->req() - sfpt->jvms()->scloff());
747 Node* res = alloc->result_cast();
748
749 assert(res == nullptr || res->is_CheckCastPP(), "unexpected AllocateNode result");
750 assert(sfpt->jvms() != nullptr, "missed JVMS");
751
752 if (res != nullptr) { // Could be null when there are no users
753 res_type = _igvn.type(res)->isa_oopptr();
754
755 if (res_type->isa_instptr()) {
756 // find the fields of the class which will be needed for safepoint debug information
757 iklass = res_type->is_instptr()->instance_klass();
758 nfields = iklass->nof_nonstatic_fields();
759 } else {
760 // find the array's elements which will be needed for safepoint debug information
761 nfields = alloc->in(AllocateNode::ALength)->find_int_con(-1);
762 assert(nfields >= 0, "must be an array klass.");
763 basic_elem_type = res_type->is_aryptr()->elem()->array_element_basic_type();
764 array_base = arrayOopDesc::base_offset_in_bytes(basic_elem_type);
765 element_size = type2aelembytes(basic_elem_type);
766 field_type = res_type->is_aryptr()->elem();
767 }
768 }
769
770 SafePointScalarObjectNode* sobj = new SafePointScalarObjectNode(res_type, alloc, first_ind, sfpt->jvms()->depth(), nfields);
771 sobj->init_req(0, C->root());
772 transform_later(sobj);
773
774 // Scan object's fields adding an input to the safepoint for each field.
775 for (int j = 0; j < nfields; j++) {
776 intptr_t offset;
777 ciField* field = nullptr;
778 if (iklass != nullptr) {
779 field = iklass->nonstatic_field_at(j);
780 offset = field->offset_in_bytes();
781 ciType* elem_type = field->type();
782 basic_elem_type = field->layout_type();
783
784 // The next code is taken from Parse::do_get_xxx().
785 if (is_reference_type(basic_elem_type)) {
786 if (!elem_type->is_loaded()) {
787 field_type = TypeInstPtr::BOTTOM;
788 } else if (field != nullptr && field->is_static_constant()) {
789 ciObject* con = field->constant_value().as_object();
790 // Do not "join" in the previous type; it doesn't add value,
791 // and may yield a vacuous result if the field is of interface type.
792 field_type = TypeOopPtr::make_from_constant(con)->isa_oopptr();
793 assert(field_type != nullptr, "field singleton type must be consistent");
794 } else {
795 field_type = TypeOopPtr::make_from_klass(elem_type->as_klass());
796 }
797 if (UseCompressedOops) {
798 field_type = field_type->make_narrowoop();
799 basic_elem_type = T_NARROWOOP;
800 }
801 } else {
802 field_type = Type::get_const_basic_type(basic_elem_type);
803 }
804 } else {
805 offset = array_base + j * (intptr_t)element_size;
806 }
807
808 const TypeOopPtr *field_addr_type = res_type->add_offset(offset)->isa_oopptr();
809
810 Node *field_val = value_from_mem(sfpt->memory(), sfpt->control(), basic_elem_type, field_type, field_addr_type, alloc);
811
812 // We weren't able to find a value for this field,
813 // give up on eliminating this allocation.
814 if (field_val == nullptr) {
815 uint last = sfpt->req() - 1;
816 for (int k = 0; k < j; k++) {
817 sfpt->del_req(last--);
818 }
819 _igvn._worklist.push(sfpt);
820
821 #ifndef PRODUCT
822 if (PrintEliminateAllocations) {
823 if (field != nullptr) {
824 tty->print("=== At SafePoint node %d can't find value of field: ", sfpt->_idx);
825 field->print();
826 int field_idx = C->get_alias_index(field_addr_type);
827 tty->print(" (alias_idx=%d)", field_idx);
828 } else { // Array's element
829 tty->print("=== At SafePoint node %d can't find value of array element [%d]", sfpt->_idx, j);
830 }
831 tty->print(", which prevents elimination of: ");
832 if (res == nullptr)
833 alloc->dump();
834 else
835 res->dump();
836 }
837 #endif
838
839 return nullptr;
840 }
841
842 if (UseCompressedOops && field_type->isa_narrowoop()) {
843 // Enable "DecodeN(EncodeP(Allocate)) --> Allocate" transformation
844 // to be able scalar replace the allocation.
845 if (field_val->is_EncodeP()) {
846 field_val = field_val->in(1);
847 } else {
848 field_val = transform_later(new DecodeNNode(field_val, field_val->get_ptr_type()));
849 }
850 }
851 sfpt->add_req(field_val);
852 }
853
854 sfpt->jvms()->set_endoff(sfpt->req());
855
856 return sobj;
857 }
858
859 // Do scalar replacement.
860 bool PhaseMacroExpand::scalar_replacement(AllocateNode *alloc, GrowableArray <SafePointNode *>& safepoints) {
861 GrowableArray <SafePointNode *> safepoints_done;
862 Node* res = alloc->result_cast();
863 assert(res == nullptr || res->is_CheckCastPP(), "unexpected AllocateNode result");
864
865 // Process the safepoint uses
866 while (safepoints.length() > 0) {
867 SafePointNode* sfpt = safepoints.pop();
868 SafePointScalarObjectNode* sobj = create_scalarized_object_description(alloc, sfpt);
869
870 if (sobj == nullptr) {
871 undo_previous_scalarizations(safepoints_done, alloc);
872 return false;
873 }
874
875 // Now make a pass over the debug information replacing any references
876 // to the allocated object with "sobj"
877 JVMState *jvms = sfpt->jvms();
878 sfpt->replace_edges_in_range(res, sobj, jvms->debug_start(), jvms->debug_end(), &_igvn);
879 _igvn._worklist.push(sfpt);
880
881 // keep it for rollback
882 safepoints_done.append_if_missing(sfpt);
883 }
884
885 return true;
886 }
887
888 static void disconnect_projections(MultiNode* n, PhaseIterGVN& igvn) {
889 Node* ctl_proj = n->proj_out_or_null(TypeFunc::Control);
890 Node* mem_proj = n->proj_out_or_null(TypeFunc::Memory);
891 if (ctl_proj != nullptr) {
892 igvn.replace_node(ctl_proj, n->in(0));
893 }
894 if (mem_proj != nullptr) {
895 igvn.replace_node(mem_proj, n->in(TypeFunc::Memory));
896 }
897 }
898
899 // Process users of eliminated allocation.
900 void PhaseMacroExpand::process_users_of_allocation(CallNode *alloc) {
901 Node* res = alloc->result_cast();
902 if (res != nullptr) {
903 for (DUIterator_Last jmin, j = res->last_outs(jmin); j >= jmin; ) {
904 Node *use = res->last_out(j);
905 uint oc1 = res->outcnt();
906
907 if (use->is_AddP()) {
908 for (DUIterator_Last kmin, k = use->last_outs(kmin); k >= kmin; ) {
909 Node *n = use->last_out(k);
910 uint oc2 = use->outcnt();
911 if (n->is_Store()) {
912 #ifdef ASSERT
913 // Verify that there is no dependent MemBarVolatile nodes,
914 // they should be removed during IGVN, see MemBarNode::Ideal().
915 for (DUIterator_Fast pmax, p = n->fast_outs(pmax);
916 p < pmax; p++) {
917 Node* mb = n->fast_out(p);
918 assert(mb->is_Initialize() || !mb->is_MemBar() ||
919 mb->req() <= MemBarNode::Precedent ||
920 mb->in(MemBarNode::Precedent) != n,
921 "MemBarVolatile should be eliminated for non-escaping object");
922 }
923 #endif
924 _igvn.replace_node(n, n->in(MemNode::Memory));
925 } else {
926 eliminate_gc_barrier(n);
927 }
928 k -= (oc2 - use->outcnt());
929 }
930 _igvn.remove_dead_node(use);
931 } else if (use->is_ArrayCopy()) {
932 // Disconnect ArrayCopy node
933 ArrayCopyNode* ac = use->as_ArrayCopy();
934 if (ac->is_clonebasic()) {
935 Node* membar_after = ac->proj_out(TypeFunc::Control)->unique_ctrl_out();
936 disconnect_projections(ac, _igvn);
937 assert(alloc->in(TypeFunc::Memory)->is_Proj() && alloc->in(TypeFunc::Memory)->in(0)->Opcode() == Op_MemBarCPUOrder, "mem barrier expected before allocation");
938 Node* membar_before = alloc->in(TypeFunc::Memory)->in(0);
939 disconnect_projections(membar_before->as_MemBar(), _igvn);
940 if (membar_after->is_MemBar()) {
941 disconnect_projections(membar_after->as_MemBar(), _igvn);
942 }
943 } else {
944 assert(ac->is_arraycopy_validated() ||
945 ac->is_copyof_validated() ||
946 ac->is_copyofrange_validated(), "unsupported");
947 CallProjections callprojs;
948 ac->extract_projections(&callprojs, true);
949
950 _igvn.replace_node(callprojs.fallthrough_ioproj, ac->in(TypeFunc::I_O));
951 _igvn.replace_node(callprojs.fallthrough_memproj, ac->in(TypeFunc::Memory));
952 _igvn.replace_node(callprojs.fallthrough_catchproj, ac->in(TypeFunc::Control));
953
954 // Set control to top. IGVN will remove the remaining projections
955 ac->set_req(0, top());
956 ac->replace_edge(res, top(), &_igvn);
957
958 // Disconnect src right away: it can help find new
959 // opportunities for allocation elimination
960 Node* src = ac->in(ArrayCopyNode::Src);
961 ac->replace_edge(src, top(), &_igvn);
962 // src can be top at this point if src and dest of the
963 // arraycopy were the same
964 if (src->outcnt() == 0 && !src->is_top()) {
965 _igvn.remove_dead_node(src);
966 }
967 }
968 _igvn._worklist.push(ac);
969 } else {
970 eliminate_gc_barrier(use);
971 }
972 j -= (oc1 - res->outcnt());
973 }
974 assert(res->outcnt() == 0, "all uses of allocated objects must be deleted");
975 _igvn.remove_dead_node(res);
976 }
977
978 //
979 // Process other users of allocation's projections
980 //
981 if (_callprojs.resproj != nullptr && _callprojs.resproj->outcnt() != 0) {
982 // First disconnect stores captured by Initialize node.
983 // If Initialize node is eliminated first in the following code,
984 // it will kill such stores and DUIterator_Last will assert.
985 for (DUIterator_Fast jmax, j = _callprojs.resproj->fast_outs(jmax); j < jmax; j++) {
986 Node* use = _callprojs.resproj->fast_out(j);
987 if (use->is_AddP()) {
988 // raw memory addresses used only by the initialization
989 _igvn.replace_node(use, C->top());
990 --j; --jmax;
991 }
992 }
993 for (DUIterator_Last jmin, j = _callprojs.resproj->last_outs(jmin); j >= jmin; ) {
994 Node* use = _callprojs.resproj->last_out(j);
995 uint oc1 = _callprojs.resproj->outcnt();
996 if (use->is_Initialize()) {
997 // Eliminate Initialize node.
998 InitializeNode *init = use->as_Initialize();
999 assert(init->outcnt() <= 2, "only a control and memory projection expected");
1000 Node *ctrl_proj = init->proj_out_or_null(TypeFunc::Control);
1001 if (ctrl_proj != nullptr) {
1002 _igvn.replace_node(ctrl_proj, init->in(TypeFunc::Control));
1003 #ifdef ASSERT
1004 // If the InitializeNode has no memory out, it will die, and tmp will become null
1005 Node* tmp = init->in(TypeFunc::Control);
1006 assert(tmp == nullptr || tmp == _callprojs.fallthrough_catchproj, "allocation control projection");
1007 #endif
1008 }
1009 Node *mem_proj = init->proj_out_or_null(TypeFunc::Memory);
1010 if (mem_proj != nullptr) {
1011 Node *mem = init->in(TypeFunc::Memory);
1012 #ifdef ASSERT
1013 if (mem->is_MergeMem()) {
1014 assert(mem->in(TypeFunc::Memory) == _callprojs.fallthrough_memproj, "allocation memory projection");
1015 } else {
1016 assert(mem == _callprojs.fallthrough_memproj, "allocation memory projection");
1017 }
1018 #endif
1019 _igvn.replace_node(mem_proj, mem);
1020 }
1021 } else {
1022 assert(false, "only Initialize or AddP expected");
1023 }
1024 j -= (oc1 - _callprojs.resproj->outcnt());
1025 }
1026 }
1027 if (_callprojs.fallthrough_catchproj != nullptr) {
1028 _igvn.replace_node(_callprojs.fallthrough_catchproj, alloc->in(TypeFunc::Control));
1029 }
1030 if (_callprojs.fallthrough_memproj != nullptr) {
1031 _igvn.replace_node(_callprojs.fallthrough_memproj, alloc->in(TypeFunc::Memory));
1032 }
1033 if (_callprojs.catchall_memproj != nullptr) {
1034 _igvn.replace_node(_callprojs.catchall_memproj, C->top());
1035 }
1036 if (_callprojs.fallthrough_ioproj != nullptr) {
1037 _igvn.replace_node(_callprojs.fallthrough_ioproj, alloc->in(TypeFunc::I_O));
1038 }
1039 if (_callprojs.catchall_ioproj != nullptr) {
1040 _igvn.replace_node(_callprojs.catchall_ioproj, C->top());
1041 }
1042 if (_callprojs.catchall_catchproj != nullptr) {
1043 _igvn.replace_node(_callprojs.catchall_catchproj, C->top());
1044 }
1045 }
1046
1047 bool PhaseMacroExpand::eliminate_allocate_node(AllocateNode *alloc) {
1048 // If reallocation fails during deoptimization we'll pop all
1049 // interpreter frames for this compiled frame and that won't play
1050 // nice with JVMTI popframe.
1051 // We avoid this issue by eager reallocation when the popframe request
1052 // is received.
1053 if (!EliminateAllocations || !alloc->_is_non_escaping) {
1054 return false;
1055 }
1056 Node* klass = alloc->in(AllocateNode::KlassNode);
1057 const TypeKlassPtr* tklass = _igvn.type(klass)->is_klassptr();
1058 Node* res = alloc->result_cast();
1059 // Eliminate boxing allocations which are not used
1060 // regardless scalar replaceable status.
1061 bool boxing_alloc = C->eliminate_boxing() &&
1062 tklass->isa_instklassptr() &&
1063 tklass->is_instklassptr()->instance_klass()->is_box_klass();
1064 if (!alloc->_is_scalar_replaceable && (!boxing_alloc || (res != nullptr))) {
1065 return false;
1066 }
1067
1068 alloc->extract_projections(&_callprojs, false /*separate_io_proj*/, false /*do_asserts*/);
1069
1070 GrowableArray <SafePointNode *> safepoints;
1071 if (!can_eliminate_allocation(&_igvn, alloc, &safepoints)) {
1072 return false;
1073 }
1074
1075 if (!alloc->_is_scalar_replaceable) {
1076 assert(res == nullptr, "sanity");
1077 // We can only eliminate allocation if all debug info references
1078 // are already replaced with SafePointScalarObject because
1079 // we can't search for a fields value without instance_id.
1080 if (safepoints.length() > 0) {
1081 return false;
1082 }
1083 }
1084
1085 if (!scalar_replacement(alloc, safepoints)) {
1086 return false;
1087 }
1088
1089 CompileLog* log = C->log();
1090 if (log != nullptr) {
1091 log->head("eliminate_allocation type='%d'",
1092 log->identify(tklass->exact_klass()));
1093 JVMState* p = alloc->jvms();
1094 while (p != nullptr) {
1095 log->elem("jvms bci='%d' method='%d'", p->bci(), log->identify(p->method()));
1096 p = p->caller();
1097 }
1098 log->tail("eliminate_allocation");
1099 }
1100
1101 process_users_of_allocation(alloc);
1102
1103 #ifndef PRODUCT
1104 if (PrintEliminateAllocations) {
1105 if (alloc->is_AllocateArray())
1106 tty->print_cr("++++ Eliminated: %d AllocateArray", alloc->_idx);
1107 else
1108 tty->print_cr("++++ Eliminated: %d Allocate", alloc->_idx);
1109 }
1110 #endif
1111
1112 return true;
1113 }
1114
1115 bool PhaseMacroExpand::eliminate_boxing_node(CallStaticJavaNode *boxing) {
1116 // EA should remove all uses of non-escaping boxing node.
1117 if (!C->eliminate_boxing() || boxing->proj_out_or_null(TypeFunc::Parms) != nullptr) {
1118 return false;
1119 }
1120
1121 assert(boxing->result_cast() == nullptr, "unexpected boxing node result");
1122
1123 boxing->extract_projections(&_callprojs, false /*separate_io_proj*/, false /*do_asserts*/);
1124
1125 const TypeTuple* r = boxing->tf()->range();
1126 assert(r->cnt() > TypeFunc::Parms, "sanity");
1127 const TypeInstPtr* t = r->field_at(TypeFunc::Parms)->isa_instptr();
1128 assert(t != nullptr, "sanity");
1129
1130 CompileLog* log = C->log();
1131 if (log != nullptr) {
1132 log->head("eliminate_boxing type='%d'",
1133 log->identify(t->instance_klass()));
1134 JVMState* p = boxing->jvms();
1135 while (p != nullptr) {
1136 log->elem("jvms bci='%d' method='%d'", p->bci(), log->identify(p->method()));
1137 p = p->caller();
1138 }
1139 log->tail("eliminate_boxing");
1140 }
1141
1142 process_users_of_allocation(boxing);
1143
1144 #ifndef PRODUCT
1145 if (PrintEliminateAllocations) {
1146 tty->print("++++ Eliminated: %d ", boxing->_idx);
1147 boxing->method()->print_short_name(tty);
1148 tty->cr();
1149 }
1150 #endif
1151
1152 return true;
1153 }
1154
1155
1156 Node* PhaseMacroExpand::make_load(Node* ctl, Node* mem, Node* base, int offset, const Type* value_type, BasicType bt) {
1157 Node* adr = basic_plus_adr(base, offset);
1158 const TypePtr* adr_type = adr->bottom_type()->is_ptr();
1159 Node* value = LoadNode::make(_igvn, ctl, mem, adr, adr_type, value_type, bt, MemNode::unordered);
1160 transform_later(value);
1161 return value;
1162 }
1163
1164
1165 Node* PhaseMacroExpand::make_store(Node* ctl, Node* mem, Node* base, int offset, Node* value, BasicType bt) {
1166 Node* adr = basic_plus_adr(base, offset);
1167 mem = StoreNode::make(_igvn, ctl, mem, adr, nullptr, value, bt, MemNode::unordered);
1168 transform_later(mem);
1169 return mem;
1170 }
1171
1172 //=============================================================================
1173 //
1174 // A L L O C A T I O N
1175 //
1176 // Allocation attempts to be fast in the case of frequent small objects.
1177 // It breaks down like this:
1178 //
1179 // 1) Size in doublewords is computed. This is a constant for objects and
1180 // variable for most arrays. Doubleword units are used to avoid size
1181 // overflow of huge doubleword arrays. We need doublewords in the end for
1182 // rounding.
1183 //
1184 // 2) Size is checked for being 'too large'. Too-large allocations will go
1185 // the slow path into the VM. The slow path can throw any required
1186 // exceptions, and does all the special checks for very large arrays. The
1187 // size test can constant-fold away for objects. For objects with
1188 // finalizers it constant-folds the otherway: you always go slow with
1189 // finalizers.
1190 //
1191 // 3) If NOT using TLABs, this is the contended loop-back point.
1192 // Load-Locked the heap top. If using TLABs normal-load the heap top.
1193 //
1194 // 4) Check that heap top + size*8 < max. If we fail go the slow ` route.
1195 // NOTE: "top+size*8" cannot wrap the 4Gig line! Here's why: for largish
1196 // "size*8" we always enter the VM, where "largish" is a constant picked small
1197 // enough that there's always space between the eden max and 4Gig (old space is
1198 // there so it's quite large) and large enough that the cost of entering the VM
1199 // is dwarfed by the cost to initialize the space.
1200 //
1201 // 5) If NOT using TLABs, Store-Conditional the adjusted heap top back
1202 // down. If contended, repeat at step 3. If using TLABs normal-store
1203 // adjusted heap top back down; there is no contention.
1204 //
1205 // 6) If !ZeroTLAB then Bulk-clear the object/array. Fill in klass & mark
1206 // fields.
1207 //
1208 // 7) Merge with the slow-path; cast the raw memory pointer to the correct
1209 // oop flavor.
1210 //
1211 //=============================================================================
1212 // FastAllocateSizeLimit value is in DOUBLEWORDS.
1213 // Allocations bigger than this always go the slow route.
1214 // This value must be small enough that allocation attempts that need to
1215 // trigger exceptions go the slow route. Also, it must be small enough so
1216 // that heap_top + size_in_bytes does not wrap around the 4Gig limit.
1217 //=============================================================================j//
1218 // %%% Here is an old comment from parseHelper.cpp; is it outdated?
1219 // The allocator will coalesce int->oop copies away. See comment in
1220 // coalesce.cpp about how this works. It depends critically on the exact
1221 // code shape produced here, so if you are changing this code shape
1222 // make sure the GC info for the heap-top is correct in and around the
1223 // slow-path call.
1224 //
1225
1226 void PhaseMacroExpand::expand_allocate_common(
1227 AllocateNode* alloc, // allocation node to be expanded
1228 Node* length, // array length for an array allocation
1229 const TypeFunc* slow_call_type, // Type of slow call
1230 address slow_call_address, // Address of slow call
1231 Node* valid_length_test // whether length is valid or not
1232 )
1233 {
1234 Node* ctrl = alloc->in(TypeFunc::Control);
1235 Node* mem = alloc->in(TypeFunc::Memory);
1236 Node* i_o = alloc->in(TypeFunc::I_O);
1237 Node* size_in_bytes = alloc->in(AllocateNode::AllocSize);
1238 Node* klass_node = alloc->in(AllocateNode::KlassNode);
1239 Node* initial_slow_test = alloc->in(AllocateNode::InitialTest);
1240 assert(ctrl != nullptr, "must have control");
1241
1242 // We need a Region and corresponding Phi's to merge the slow-path and fast-path results.
1243 // they will not be used if "always_slow" is set
1244 enum { slow_result_path = 1, fast_result_path = 2 };
1245 Node *result_region = nullptr;
1246 Node *result_phi_rawmem = nullptr;
1247 Node *result_phi_rawoop = nullptr;
1248 Node *result_phi_i_o = nullptr;
1249
1250 // The initial slow comparison is a size check, the comparison
1251 // we want to do is a BoolTest::gt
1252 bool expand_fast_path = true;
1253 int tv = _igvn.find_int_con(initial_slow_test, -1);
1254 if (tv >= 0) {
1255 // InitialTest has constant result
1256 // 0 - can fit in TLAB
1257 // 1 - always too big or negative
1258 assert(tv <= 1, "0 or 1 if a constant");
1259 expand_fast_path = (tv == 0);
1260 initial_slow_test = nullptr;
1261 } else {
1262 initial_slow_test = BoolNode::make_predicate(initial_slow_test, &_igvn);
1263 }
1264
1265 if (!UseTLAB) {
1266 // Force slow-path allocation
1267 expand_fast_path = false;
1268 initial_slow_test = nullptr;
1269 }
1270
1271 bool allocation_has_use = (alloc->result_cast() != nullptr);
1272 if (!allocation_has_use) {
1273 InitializeNode* init = alloc->initialization();
1274 if (init != nullptr) {
1275 init->remove(&_igvn);
1276 }
1277 if (expand_fast_path && (initial_slow_test == nullptr)) {
1278 // Remove allocation node and return.
1279 // Size is a non-negative constant -> no initial check needed -> directly to fast path.
1280 // Also, no usages -> empty fast path -> no fall out to slow path -> nothing left.
1281 #ifndef PRODUCT
1282 if (PrintEliminateAllocations) {
1283 tty->print("NotUsed ");
1284 Node* res = alloc->proj_out_or_null(TypeFunc::Parms);
1285 if (res != nullptr) {
1286 res->dump();
1287 } else {
1288 alloc->dump();
1289 }
1290 }
1291 #endif
1292 yank_alloc_node(alloc);
1293 return;
1294 }
1295 }
1296
1297 enum { too_big_or_final_path = 1, need_gc_path = 2 };
1298 Node *slow_region = nullptr;
1299 Node *toobig_false = ctrl;
1300
1301 // generate the initial test if necessary
1302 if (initial_slow_test != nullptr ) {
1303 assert (expand_fast_path, "Only need test if there is a fast path");
1304 slow_region = new RegionNode(3);
1305
1306 // Now make the initial failure test. Usually a too-big test but
1307 // might be a TRUE for finalizers.
1308 IfNode *toobig_iff = new IfNode(ctrl, initial_slow_test, PROB_MIN, COUNT_UNKNOWN);
1309 transform_later(toobig_iff);
1310 // Plug the failing-too-big test into the slow-path region
1311 Node *toobig_true = new IfTrueNode( toobig_iff );
1312 transform_later(toobig_true);
1313 slow_region ->init_req( too_big_or_final_path, toobig_true );
1314 toobig_false = new IfFalseNode( toobig_iff );
1315 transform_later(toobig_false);
1316 } else {
1317 // No initial test, just fall into next case
1318 assert(allocation_has_use || !expand_fast_path, "Should already have been handled");
1319 toobig_false = ctrl;
1320 DEBUG_ONLY(slow_region = NodeSentinel);
1321 }
1322
1323 // If we are here there are several possibilities
1324 // - expand_fast_path is false - then only a slow path is expanded. That's it.
1325 // no_initial_check means a constant allocation.
1326 // - If check always evaluates to false -> expand_fast_path is false (see above)
1327 // - If check always evaluates to true -> directly into fast path (but may bailout to slowpath)
1328 // if !allocation_has_use the fast path is empty
1329 // if !allocation_has_use && no_initial_check
1330 // - Then there are no fastpath that can fall out to slowpath -> no allocation code at all.
1331 // removed by yank_alloc_node above.
1332
1333 Node *slow_mem = mem; // save the current memory state for slow path
1334 // generate the fast allocation code unless we know that the initial test will always go slow
1335 if (expand_fast_path) {
1336 // Fast path modifies only raw memory.
1337 if (mem->is_MergeMem()) {
1338 mem = mem->as_MergeMem()->memory_at(Compile::AliasIdxRaw);
1339 }
1340
1341 // allocate the Region and Phi nodes for the result
1342 result_region = new RegionNode(3);
1343 result_phi_rawmem = new PhiNode(result_region, Type::MEMORY, TypeRawPtr::BOTTOM);
1344 result_phi_i_o = new PhiNode(result_region, Type::ABIO); // I/O is used for Prefetch
1345
1346 // Grab regular I/O before optional prefetch may change it.
1347 // Slow-path does no I/O so just set it to the original I/O.
1348 result_phi_i_o->init_req(slow_result_path, i_o);
1349
1350 // Name successful fast-path variables
1351 Node* fast_oop_ctrl;
1352 Node* fast_oop_rawmem;
1353 if (allocation_has_use) {
1354 Node* needgc_ctrl = nullptr;
1355 result_phi_rawoop = new PhiNode(result_region, TypeRawPtr::BOTTOM);
1356
1357 intx prefetch_lines = length != nullptr ? AllocatePrefetchLines : AllocateInstancePrefetchLines;
1358 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
1359 Node* fast_oop = bs->obj_allocate(this, mem, toobig_false, size_in_bytes, i_o, needgc_ctrl,
1360 fast_oop_ctrl, fast_oop_rawmem,
1361 prefetch_lines);
1362
1363 if (initial_slow_test != nullptr) {
1364 // This completes all paths into the slow merge point
1365 slow_region->init_req(need_gc_path, needgc_ctrl);
1366 transform_later(slow_region);
1367 } else {
1368 // No initial slow path needed!
1369 // Just fall from the need-GC path straight into the VM call.
1370 slow_region = needgc_ctrl;
1371 }
1372
1373 InitializeNode* init = alloc->initialization();
1374 fast_oop_rawmem = initialize_object(alloc,
1375 fast_oop_ctrl, fast_oop_rawmem, fast_oop,
1376 klass_node, length, size_in_bytes);
1377 expand_initialize_membar(alloc, init, fast_oop_ctrl, fast_oop_rawmem);
1378 expand_dtrace_alloc_probe(alloc, fast_oop, fast_oop_ctrl, fast_oop_rawmem);
1379
1380 result_phi_rawoop->init_req(fast_result_path, fast_oop);
1381 } else {
1382 assert (initial_slow_test != nullptr, "sanity");
1383 fast_oop_ctrl = toobig_false;
1384 fast_oop_rawmem = mem;
1385 transform_later(slow_region);
1386 }
1387
1388 // Plug in the successful fast-path into the result merge point
1389 result_region ->init_req(fast_result_path, fast_oop_ctrl);
1390 result_phi_i_o ->init_req(fast_result_path, i_o);
1391 result_phi_rawmem->init_req(fast_result_path, fast_oop_rawmem);
1392 } else {
1393 slow_region = ctrl;
1394 result_phi_i_o = i_o; // Rename it to use in the following code.
1395 }
1396
1397 // Generate slow-path call
1398 CallNode *call = new CallStaticJavaNode(slow_call_type, slow_call_address,
1399 OptoRuntime::stub_name(slow_call_address),
1400 TypePtr::BOTTOM);
1401 call->init_req(TypeFunc::Control, slow_region);
1402 call->init_req(TypeFunc::I_O, top()); // does no i/o
1403 call->init_req(TypeFunc::Memory, slow_mem); // may gc ptrs
1404 call->init_req(TypeFunc::ReturnAdr, alloc->in(TypeFunc::ReturnAdr));
1405 call->init_req(TypeFunc::FramePtr, alloc->in(TypeFunc::FramePtr));
1406
1407 call->init_req(TypeFunc::Parms+0, klass_node);
1408 if (length != nullptr) {
1409 call->init_req(TypeFunc::Parms+1, length);
1410 }
1411
1412 // Copy debug information and adjust JVMState information, then replace
1413 // allocate node with the call
1414 call->copy_call_debug_info(&_igvn, alloc);
1415 // For array allocations, copy the valid length check to the call node so Compile::final_graph_reshaping() can verify
1416 // that the call has the expected number of CatchProj nodes (in case the allocation always fails and the fallthrough
1417 // path dies).
1418 if (valid_length_test != nullptr) {
1419 call->add_req(valid_length_test);
1420 }
1421 if (expand_fast_path) {
1422 call->set_cnt(PROB_UNLIKELY_MAG(4)); // Same effect as RC_UNCOMMON.
1423 } else {
1424 // Hook i_o projection to avoid its elimination during allocation
1425 // replacement (when only a slow call is generated).
1426 call->set_req(TypeFunc::I_O, result_phi_i_o);
1427 }
1428 _igvn.replace_node(alloc, call);
1429 transform_later(call);
1430
1431 // Identify the output projections from the allocate node and
1432 // adjust any references to them.
1433 // The control and io projections look like:
1434 //
1435 // v---Proj(ctrl) <-----+ v---CatchProj(ctrl)
1436 // Allocate Catch
1437 // ^---Proj(io) <-------+ ^---CatchProj(io)
1438 //
1439 // We are interested in the CatchProj nodes.
1440 //
1441 call->extract_projections(&_callprojs, false /*separate_io_proj*/, false /*do_asserts*/);
1442
1443 // An allocate node has separate memory projections for the uses on
1444 // the control and i_o paths. Replace the control memory projection with
1445 // result_phi_rawmem (unless we are only generating a slow call when
1446 // both memory projections are combined)
1447 if (expand_fast_path && _callprojs.fallthrough_memproj != nullptr) {
1448 migrate_outs(_callprojs.fallthrough_memproj, result_phi_rawmem);
1449 }
1450 // Now change uses of catchall_memproj to use fallthrough_memproj and delete
1451 // catchall_memproj so we end up with a call that has only 1 memory projection.
1452 if (_callprojs.catchall_memproj != nullptr ) {
1453 if (_callprojs.fallthrough_memproj == nullptr) {
1454 _callprojs.fallthrough_memproj = new ProjNode(call, TypeFunc::Memory);
1455 transform_later(_callprojs.fallthrough_memproj);
1456 }
1457 migrate_outs(_callprojs.catchall_memproj, _callprojs.fallthrough_memproj);
1458 _igvn.remove_dead_node(_callprojs.catchall_memproj);
1459 }
1460
1461 // An allocate node has separate i_o projections for the uses on the control
1462 // and i_o paths. Always replace the control i_o projection with result i_o
1463 // otherwise incoming i_o become dead when only a slow call is generated
1464 // (it is different from memory projections where both projections are
1465 // combined in such case).
1466 if (_callprojs.fallthrough_ioproj != nullptr) {
1467 migrate_outs(_callprojs.fallthrough_ioproj, result_phi_i_o);
1468 }
1469 // Now change uses of catchall_ioproj to use fallthrough_ioproj and delete
1470 // catchall_ioproj so we end up with a call that has only 1 i_o projection.
1471 if (_callprojs.catchall_ioproj != nullptr ) {
1472 if (_callprojs.fallthrough_ioproj == nullptr) {
1473 _callprojs.fallthrough_ioproj = new ProjNode(call, TypeFunc::I_O);
1474 transform_later(_callprojs.fallthrough_ioproj);
1475 }
1476 migrate_outs(_callprojs.catchall_ioproj, _callprojs.fallthrough_ioproj);
1477 _igvn.remove_dead_node(_callprojs.catchall_ioproj);
1478 }
1479
1480 // if we generated only a slow call, we are done
1481 if (!expand_fast_path) {
1482 // Now we can unhook i_o.
1483 if (result_phi_i_o->outcnt() > 1) {
1484 call->set_req(TypeFunc::I_O, top());
1485 } else {
1486 assert(result_phi_i_o->unique_ctrl_out() == call, "sanity");
1487 // Case of new array with negative size known during compilation.
1488 // AllocateArrayNode::Ideal() optimization disconnect unreachable
1489 // following code since call to runtime will throw exception.
1490 // As result there will be no users of i_o after the call.
1491 // Leave i_o attached to this call to avoid problems in preceding graph.
1492 }
1493 return;
1494 }
1495
1496 if (_callprojs.fallthrough_catchproj != nullptr) {
1497 ctrl = _callprojs.fallthrough_catchproj->clone();
1498 transform_later(ctrl);
1499 _igvn.replace_node(_callprojs.fallthrough_catchproj, result_region);
1500 } else {
1501 ctrl = top();
1502 }
1503 Node *slow_result;
1504 if (_callprojs.resproj == nullptr) {
1505 // no uses of the allocation result
1506 slow_result = top();
1507 } else {
1508 slow_result = _callprojs.resproj->clone();
1509 transform_later(slow_result);
1510 _igvn.replace_node(_callprojs.resproj, result_phi_rawoop);
1511 }
1512
1513 // Plug slow-path into result merge point
1514 result_region->init_req( slow_result_path, ctrl);
1515 transform_later(result_region);
1516 if (allocation_has_use) {
1517 result_phi_rawoop->init_req(slow_result_path, slow_result);
1518 transform_later(result_phi_rawoop);
1519 }
1520 result_phi_rawmem->init_req(slow_result_path, _callprojs.fallthrough_memproj);
1521 transform_later(result_phi_rawmem);
1522 transform_later(result_phi_i_o);
1523 // This completes all paths into the result merge point
1524 }
1525
1526 // Remove alloc node that has no uses.
1527 void PhaseMacroExpand::yank_alloc_node(AllocateNode* alloc) {
1528 Node* ctrl = alloc->in(TypeFunc::Control);
1529 Node* mem = alloc->in(TypeFunc::Memory);
1530 Node* i_o = alloc->in(TypeFunc::I_O);
1531
1532 alloc->extract_projections(&_callprojs, false /*separate_io_proj*/, false /*do_asserts*/);
1533 if (_callprojs.resproj != nullptr) {
1534 for (DUIterator_Fast imax, i = _callprojs.resproj->fast_outs(imax); i < imax; i++) {
1535 Node* use = _callprojs.resproj->fast_out(i);
1536 use->isa_MemBar()->remove(&_igvn);
1537 --imax;
1538 --i; // back up iterator
1539 }
1540 assert(_callprojs.resproj->outcnt() == 0, "all uses must be deleted");
1541 _igvn.remove_dead_node(_callprojs.resproj);
1542 }
1543 if (_callprojs.fallthrough_catchproj != nullptr) {
1544 migrate_outs(_callprojs.fallthrough_catchproj, ctrl);
1545 _igvn.remove_dead_node(_callprojs.fallthrough_catchproj);
1546 }
1547 if (_callprojs.catchall_catchproj != nullptr) {
1548 _igvn.rehash_node_delayed(_callprojs.catchall_catchproj);
1549 _callprojs.catchall_catchproj->set_req(0, top());
1550 }
1551 if (_callprojs.fallthrough_proj != nullptr) {
1552 Node* catchnode = _callprojs.fallthrough_proj->unique_ctrl_out();
1553 _igvn.remove_dead_node(catchnode);
1554 _igvn.remove_dead_node(_callprojs.fallthrough_proj);
1555 }
1556 if (_callprojs.fallthrough_memproj != nullptr) {
1557 migrate_outs(_callprojs.fallthrough_memproj, mem);
1558 _igvn.remove_dead_node(_callprojs.fallthrough_memproj);
1559 }
1560 if (_callprojs.fallthrough_ioproj != nullptr) {
1561 migrate_outs(_callprojs.fallthrough_ioproj, i_o);
1562 _igvn.remove_dead_node(_callprojs.fallthrough_ioproj);
1563 }
1564 if (_callprojs.catchall_memproj != nullptr) {
1565 _igvn.rehash_node_delayed(_callprojs.catchall_memproj);
1566 _callprojs.catchall_memproj->set_req(0, top());
1567 }
1568 if (_callprojs.catchall_ioproj != nullptr) {
1569 _igvn.rehash_node_delayed(_callprojs.catchall_ioproj);
1570 _callprojs.catchall_ioproj->set_req(0, top());
1571 }
1572 #ifndef PRODUCT
1573 if (PrintEliminateAllocations) {
1574 if (alloc->is_AllocateArray()) {
1575 tty->print_cr("++++ Eliminated: %d AllocateArray", alloc->_idx);
1576 } else {
1577 tty->print_cr("++++ Eliminated: %d Allocate", alloc->_idx);
1578 }
1579 }
1580 #endif
1581 _igvn.remove_dead_node(alloc);
1582 }
1583
1584 void PhaseMacroExpand::expand_initialize_membar(AllocateNode* alloc, InitializeNode* init,
1585 Node*& fast_oop_ctrl, Node*& fast_oop_rawmem) {
1586 // If initialization is performed by an array copy, any required
1587 // MemBarStoreStore was already added. If the object does not
1588 // escape no need for a MemBarStoreStore. If the object does not
1589 // escape in its initializer and memory barrier (MemBarStoreStore or
1590 // stronger) is already added at exit of initializer, also no need
1591 // for a MemBarStoreStore. Otherwise we need a MemBarStoreStore
1592 // so that stores that initialize this object can't be reordered
1593 // with a subsequent store that makes this object accessible by
1594 // other threads.
1595 // Other threads include java threads and JVM internal threads
1596 // (for example concurrent GC threads). Current concurrent GC
1597 // implementation: G1 will not scan newly created object,
1598 // so it's safe to skip storestore barrier when allocation does
1599 // not escape.
1600 if (!alloc->does_not_escape_thread() &&
1601 !alloc->is_allocation_MemBar_redundant() &&
1602 (init == nullptr || !init->is_complete_with_arraycopy())) {
1603 if (init == nullptr || init->req() < InitializeNode::RawStores) {
1604 // No InitializeNode or no stores captured by zeroing
1605 // elimination. Simply add the MemBarStoreStore after object
1606 // initialization.
1607 MemBarNode* mb = MemBarNode::make(C, Op_MemBarStoreStore, Compile::AliasIdxBot);
1608 transform_later(mb);
1609
1610 mb->init_req(TypeFunc::Memory, fast_oop_rawmem);
1611 mb->init_req(TypeFunc::Control, fast_oop_ctrl);
1612 fast_oop_ctrl = new ProjNode(mb, TypeFunc::Control);
1613 transform_later(fast_oop_ctrl);
1614 fast_oop_rawmem = new ProjNode(mb, TypeFunc::Memory);
1615 transform_later(fast_oop_rawmem);
1616 } else {
1617 // Add the MemBarStoreStore after the InitializeNode so that
1618 // all stores performing the initialization that were moved
1619 // before the InitializeNode happen before the storestore
1620 // barrier.
1621
1622 Node* init_ctrl = init->proj_out_or_null(TypeFunc::Control);
1623 Node* init_mem = init->proj_out_or_null(TypeFunc::Memory);
1624
1625 MemBarNode* mb = MemBarNode::make(C, Op_MemBarStoreStore, Compile::AliasIdxBot);
1626 transform_later(mb);
1627
1628 Node* ctrl = new ProjNode(init, TypeFunc::Control);
1629 transform_later(ctrl);
1630 Node* mem = new ProjNode(init, TypeFunc::Memory);
1631 transform_later(mem);
1632
1633 // The MemBarStoreStore depends on control and memory coming
1634 // from the InitializeNode
1635 mb->init_req(TypeFunc::Memory, mem);
1636 mb->init_req(TypeFunc::Control, ctrl);
1637
1638 ctrl = new ProjNode(mb, TypeFunc::Control);
1639 transform_later(ctrl);
1640 mem = new ProjNode(mb, TypeFunc::Memory);
1641 transform_later(mem);
1642
1643 // All nodes that depended on the InitializeNode for control
1644 // and memory must now depend on the MemBarNode that itself
1645 // depends on the InitializeNode
1646 if (init_ctrl != nullptr) {
1647 _igvn.replace_node(init_ctrl, ctrl);
1648 }
1649 if (init_mem != nullptr) {
1650 _igvn.replace_node(init_mem, mem);
1651 }
1652 }
1653 }
1654 }
1655
1656 void PhaseMacroExpand::expand_dtrace_alloc_probe(AllocateNode* alloc, Node* oop,
1657 Node*& ctrl, Node*& rawmem) {
1658 if (C->env()->dtrace_alloc_probes()) {
1659 // Slow-path call
1660 int size = TypeFunc::Parms + 2;
1661 CallLeafNode *call = new CallLeafNode(OptoRuntime::dtrace_object_alloc_Type(),
1662 CAST_FROM_FN_PTR(address,
1663 static_cast<int (*)(JavaThread*, oopDesc*)>(SharedRuntime::dtrace_object_alloc)),
1664 "dtrace_object_alloc",
1665 TypeRawPtr::BOTTOM);
1666
1667 // Get base of thread-local storage area
1668 Node* thread = new ThreadLocalNode();
1669 transform_later(thread);
1670
1671 call->init_req(TypeFunc::Parms + 0, thread);
1672 call->init_req(TypeFunc::Parms + 1, oop);
1673 call->init_req(TypeFunc::Control, ctrl);
1674 call->init_req(TypeFunc::I_O , top()); // does no i/o
1675 call->init_req(TypeFunc::Memory , rawmem);
1676 call->init_req(TypeFunc::ReturnAdr, alloc->in(TypeFunc::ReturnAdr));
1677 call->init_req(TypeFunc::FramePtr, alloc->in(TypeFunc::FramePtr));
1678 transform_later(call);
1679 ctrl = new ProjNode(call, TypeFunc::Control);
1680 transform_later(ctrl);
1681 rawmem = new ProjNode(call, TypeFunc::Memory);
1682 transform_later(rawmem);
1683 }
1684 }
1685
1686 // Helper for PhaseMacroExpand::expand_allocate_common.
1687 // Initializes the newly-allocated storage.
1688 Node*
1689 PhaseMacroExpand::initialize_object(AllocateNode* alloc,
1690 Node* control, Node* rawmem, Node* object,
1691 Node* klass_node, Node* length,
1692 Node* size_in_bytes) {
1693 InitializeNode* init = alloc->initialization();
1694 // Store the klass & mark bits
1695 Node* mark_node = alloc->make_ideal_mark(&_igvn, object, control, rawmem);
1696 if (!mark_node->is_Con()) {
1697 transform_later(mark_node);
1698 }
1699 rawmem = make_store(control, rawmem, object, oopDesc::mark_offset_in_bytes(), mark_node, TypeX_X->basic_type());
1700
1701 if (!UseCompactObjectHeaders) {
1702 rawmem = make_store(control, rawmem, object, Type::klass_offset(), klass_node, T_METADATA);
1703 }
1704 int header_size = alloc->minimum_header_size(); // conservatively small
1705
1706 // Array length
1707 if (length != nullptr) { // Arrays need length field
1708 rawmem = make_store(control, rawmem, object, arrayOopDesc::length_offset_in_bytes(), length, T_INT);
1709 // conservatively small header size:
1710 header_size = arrayOopDesc::base_offset_in_bytes(T_BYTE);
1711 if (_igvn.type(klass_node)->isa_aryklassptr()) { // we know the exact header size in most cases:
1712 BasicType elem = _igvn.type(klass_node)->is_klassptr()->as_instance_type()->isa_aryptr()->elem()->array_element_basic_type();
1713 if (is_reference_type(elem, true)) {
1714 elem = T_OBJECT;
1715 }
1716 header_size = Klass::layout_helper_header_size(Klass::array_layout_helper(elem));
1717 }
1718 }
1719
1720 // Clear the object body, if necessary.
1721 if (init == nullptr) {
1722 // The init has somehow disappeared; be cautious and clear everything.
1723 //
1724 // This can happen if a node is allocated but an uncommon trap occurs
1725 // immediately. In this case, the Initialize gets associated with the
1726 // trap, and may be placed in a different (outer) loop, if the Allocate
1727 // is in a loop. If (this is rare) the inner loop gets unrolled, then
1728 // there can be two Allocates to one Initialize. The answer in all these
1729 // edge cases is safety first. It is always safe to clear immediately
1730 // within an Allocate, and then (maybe or maybe not) clear some more later.
1731 if (!(UseTLAB && ZeroTLAB)) {
1732 rawmem = ClearArrayNode::clear_memory(control, rawmem, object,
1733 header_size, size_in_bytes,
1734 &_igvn);
1735 }
1736 } else {
1737 if (!init->is_complete()) {
1738 // Try to win by zeroing only what the init does not store.
1739 // We can also try to do some peephole optimizations,
1740 // such as combining some adjacent subword stores.
1741 rawmem = init->complete_stores(control, rawmem, object,
1742 header_size, size_in_bytes, &_igvn);
1743 }
1744 // We have no more use for this link, since the AllocateNode goes away:
1745 init->set_req(InitializeNode::RawAddress, top());
1746 // (If we keep the link, it just confuses the register allocator,
1747 // who thinks he sees a real use of the address by the membar.)
1748 }
1749
1750 return rawmem;
1751 }
1752
1753 // Generate prefetch instructions for next allocations.
1754 Node* PhaseMacroExpand::prefetch_allocation(Node* i_o, Node*& needgc_false,
1755 Node*& contended_phi_rawmem,
1756 Node* old_eden_top, Node* new_eden_top,
1757 intx lines) {
1758 enum { fall_in_path = 1, pf_path = 2 };
1759 if( UseTLAB && AllocatePrefetchStyle == 2 ) {
1760 // Generate prefetch allocation with watermark check.
1761 // As an allocation hits the watermark, we will prefetch starting
1762 // at a "distance" away from watermark.
1763
1764 Node *pf_region = new RegionNode(3);
1765 Node *pf_phi_rawmem = new PhiNode( pf_region, Type::MEMORY,
1766 TypeRawPtr::BOTTOM );
1767 // I/O is used for Prefetch
1768 Node *pf_phi_abio = new PhiNode( pf_region, Type::ABIO );
1769
1770 Node *thread = new ThreadLocalNode();
1771 transform_later(thread);
1772
1773 Node *eden_pf_adr = new AddPNode( top()/*not oop*/, thread,
1774 _igvn.MakeConX(in_bytes(JavaThread::tlab_pf_top_offset())) );
1775 transform_later(eden_pf_adr);
1776
1777 Node *old_pf_wm = new LoadPNode(needgc_false,
1778 contended_phi_rawmem, eden_pf_adr,
1779 TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM,
1780 MemNode::unordered);
1781 transform_later(old_pf_wm);
1782
1783 // check against new_eden_top
1784 Node *need_pf_cmp = new CmpPNode( new_eden_top, old_pf_wm );
1785 transform_later(need_pf_cmp);
1786 Node *need_pf_bol = new BoolNode( need_pf_cmp, BoolTest::ge );
1787 transform_later(need_pf_bol);
1788 IfNode *need_pf_iff = new IfNode( needgc_false, need_pf_bol,
1789 PROB_UNLIKELY_MAG(4), COUNT_UNKNOWN );
1790 transform_later(need_pf_iff);
1791
1792 // true node, add prefetchdistance
1793 Node *need_pf_true = new IfTrueNode( need_pf_iff );
1794 transform_later(need_pf_true);
1795
1796 Node *need_pf_false = new IfFalseNode( need_pf_iff );
1797 transform_later(need_pf_false);
1798
1799 Node *new_pf_wmt = new AddPNode( top(), old_pf_wm,
1800 _igvn.MakeConX(AllocatePrefetchDistance) );
1801 transform_later(new_pf_wmt );
1802 new_pf_wmt->set_req(0, need_pf_true);
1803
1804 Node *store_new_wmt = new StorePNode(need_pf_true,
1805 contended_phi_rawmem, eden_pf_adr,
1806 TypeRawPtr::BOTTOM, new_pf_wmt,
1807 MemNode::unordered);
1808 transform_later(store_new_wmt);
1809
1810 // adding prefetches
1811 pf_phi_abio->init_req( fall_in_path, i_o );
1812
1813 Node *prefetch_adr;
1814 Node *prefetch;
1815 uint step_size = AllocatePrefetchStepSize;
1816 uint distance = 0;
1817
1818 for ( intx i = 0; i < lines; i++ ) {
1819 prefetch_adr = new AddPNode( old_pf_wm, new_pf_wmt,
1820 _igvn.MakeConX(distance) );
1821 transform_later(prefetch_adr);
1822 prefetch = new PrefetchAllocationNode( i_o, prefetch_adr );
1823 transform_later(prefetch);
1824 distance += step_size;
1825 i_o = prefetch;
1826 }
1827 pf_phi_abio->set_req( pf_path, i_o );
1828
1829 pf_region->init_req( fall_in_path, need_pf_false );
1830 pf_region->init_req( pf_path, need_pf_true );
1831
1832 pf_phi_rawmem->init_req( fall_in_path, contended_phi_rawmem );
1833 pf_phi_rawmem->init_req( pf_path, store_new_wmt );
1834
1835 transform_later(pf_region);
1836 transform_later(pf_phi_rawmem);
1837 transform_later(pf_phi_abio);
1838
1839 needgc_false = pf_region;
1840 contended_phi_rawmem = pf_phi_rawmem;
1841 i_o = pf_phi_abio;
1842 } else if( UseTLAB && AllocatePrefetchStyle == 3 ) {
1843 // Insert a prefetch instruction for each allocation.
1844 // This code is used to generate 1 prefetch instruction per cache line.
1845
1846 // Generate several prefetch instructions.
1847 uint step_size = AllocatePrefetchStepSize;
1848 uint distance = AllocatePrefetchDistance;
1849
1850 // Next cache address.
1851 Node *cache_adr = new AddPNode(old_eden_top, old_eden_top,
1852 _igvn.MakeConX(step_size + distance));
1853 transform_later(cache_adr);
1854 cache_adr = new CastP2XNode(needgc_false, cache_adr);
1855 transform_later(cache_adr);
1856 // Address is aligned to execute prefetch to the beginning of cache line size
1857 // (it is important when BIS instruction is used on SPARC as prefetch).
1858 Node* mask = _igvn.MakeConX(~(intptr_t)(step_size-1));
1859 cache_adr = new AndXNode(cache_adr, mask);
1860 transform_later(cache_adr);
1861 cache_adr = new CastX2PNode(cache_adr);
1862 transform_later(cache_adr);
1863
1864 // Prefetch
1865 Node *prefetch = new PrefetchAllocationNode( contended_phi_rawmem, cache_adr );
1866 prefetch->set_req(0, needgc_false);
1867 transform_later(prefetch);
1868 contended_phi_rawmem = prefetch;
1869 Node *prefetch_adr;
1870 distance = step_size;
1871 for ( intx i = 1; i < lines; i++ ) {
1872 prefetch_adr = new AddPNode( cache_adr, cache_adr,
1873 _igvn.MakeConX(distance) );
1874 transform_later(prefetch_adr);
1875 prefetch = new PrefetchAllocationNode( contended_phi_rawmem, prefetch_adr );
1876 transform_later(prefetch);
1877 distance += step_size;
1878 contended_phi_rawmem = prefetch;
1879 }
1880 } else if( AllocatePrefetchStyle > 0 ) {
1881 // Insert a prefetch for each allocation only on the fast-path
1882 Node *prefetch_adr;
1883 Node *prefetch;
1884 // Generate several prefetch instructions.
1885 uint step_size = AllocatePrefetchStepSize;
1886 uint distance = AllocatePrefetchDistance;
1887 for ( intx i = 0; i < lines; i++ ) {
1888 prefetch_adr = new AddPNode( old_eden_top, new_eden_top,
1889 _igvn.MakeConX(distance) );
1890 transform_later(prefetch_adr);
1891 prefetch = new PrefetchAllocationNode( i_o, prefetch_adr );
1892 // Do not let it float too high, since if eden_top == eden_end,
1893 // both might be null.
1894 if( i == 0 ) { // Set control for first prefetch, next follows it
1895 prefetch->init_req(0, needgc_false);
1896 }
1897 transform_later(prefetch);
1898 distance += step_size;
1899 i_o = prefetch;
1900 }
1901 }
1902 return i_o;
1903 }
1904
1905
1906 void PhaseMacroExpand::expand_allocate(AllocateNode *alloc) {
1907 expand_allocate_common(alloc, nullptr,
1908 OptoRuntime::new_instance_Type(),
1909 OptoRuntime::new_instance_Java(), nullptr);
1910 }
1911
1912 void PhaseMacroExpand::expand_allocate_array(AllocateArrayNode *alloc) {
1913 Node* length = alloc->in(AllocateNode::ALength);
1914 Node* valid_length_test = alloc->in(AllocateNode::ValidLengthTest);
1915 InitializeNode* init = alloc->initialization();
1916 Node* klass_node = alloc->in(AllocateNode::KlassNode);
1917 const TypeAryKlassPtr* ary_klass_t = _igvn.type(klass_node)->isa_aryklassptr();
1918 address slow_call_address; // Address of slow call
1919 if (init != nullptr && init->is_complete_with_arraycopy() &&
1920 ary_klass_t && ary_klass_t->elem()->isa_klassptr() == nullptr) {
1921 // Don't zero type array during slow allocation in VM since
1922 // it will be initialized later by arraycopy in compiled code.
1923 slow_call_address = OptoRuntime::new_array_nozero_Java();
1924 } else {
1925 slow_call_address = OptoRuntime::new_array_Java();
1926 }
1927 expand_allocate_common(alloc, length,
1928 OptoRuntime::new_array_Type(),
1929 slow_call_address, valid_length_test);
1930 }
1931
1932 //-------------------mark_eliminated_box----------------------------------
1933 //
1934 // During EA obj may point to several objects but after few ideal graph
1935 // transformations (CCP) it may point to only one non escaping object
1936 // (but still using phi), corresponding locks and unlocks will be marked
1937 // for elimination. Later obj could be replaced with a new node (new phi)
1938 // and which does not have escape information. And later after some graph
1939 // reshape other locks and unlocks (which were not marked for elimination
1940 // before) are connected to this new obj (phi) but they still will not be
1941 // marked for elimination since new obj has no escape information.
1942 // Mark all associated (same box and obj) lock and unlock nodes for
1943 // elimination if some of them marked already.
1944 void PhaseMacroExpand::mark_eliminated_box(Node* box, Node* obj) {
1945 BoxLockNode* oldbox = box->as_BoxLock();
1946 if (oldbox->is_eliminated()) {
1947 return; // This BoxLock node was processed already.
1948 }
1949 assert(!oldbox->is_unbalanced(), "this should not be called for unbalanced region");
1950 // New implementation (EliminateNestedLocks) has separate BoxLock
1951 // node for each locked region so mark all associated locks/unlocks as
1952 // eliminated even if different objects are referenced in one locked region
1953 // (for example, OSR compilation of nested loop inside locked scope).
1954 if (EliminateNestedLocks ||
1955 oldbox->as_BoxLock()->is_simple_lock_region(nullptr, obj, nullptr)) {
1956 // Box is used only in one lock region. Mark this box as eliminated.
1957 oldbox->set_local(); // This verifies correct state of BoxLock
1958 _igvn.hash_delete(oldbox);
1959 oldbox->set_eliminated(); // This changes box's hash value
1960 _igvn.hash_insert(oldbox);
1961
1962 for (uint i = 0; i < oldbox->outcnt(); i++) {
1963 Node* u = oldbox->raw_out(i);
1964 if (u->is_AbstractLock() && !u->as_AbstractLock()->is_non_esc_obj()) {
1965 AbstractLockNode* alock = u->as_AbstractLock();
1966 // Check lock's box since box could be referenced by Lock's debug info.
1967 if (alock->box_node() == oldbox) {
1968 // Mark eliminated all related locks and unlocks.
1969 #ifdef ASSERT
1970 alock->log_lock_optimization(C, "eliminate_lock_set_non_esc4");
1971 #endif
1972 alock->set_non_esc_obj();
1973 }
1974 }
1975 }
1976 return;
1977 }
1978
1979 // Create new "eliminated" BoxLock node and use it in monitor debug info
1980 // instead of oldbox for the same object.
1981 BoxLockNode* newbox = oldbox->clone()->as_BoxLock();
1982
1983 // Note: BoxLock node is marked eliminated only here and it is used
1984 // to indicate that all associated lock and unlock nodes are marked
1985 // for elimination.
1986 newbox->set_local(); // This verifies correct state of BoxLock
1987 newbox->set_eliminated();
1988 transform_later(newbox);
1989
1990 // Replace old box node with new box for all users of the same object.
1991 for (uint i = 0; i < oldbox->outcnt();) {
1992 bool next_edge = true;
1993
1994 Node* u = oldbox->raw_out(i);
1995 if (u->is_AbstractLock()) {
1996 AbstractLockNode* alock = u->as_AbstractLock();
1997 if (alock->box_node() == oldbox && alock->obj_node()->eqv_uncast(obj)) {
1998 // Replace Box and mark eliminated all related locks and unlocks.
1999 #ifdef ASSERT
2000 alock->log_lock_optimization(C, "eliminate_lock_set_non_esc5");
2001 #endif
2002 alock->set_non_esc_obj();
2003 _igvn.rehash_node_delayed(alock);
2004 alock->set_box_node(newbox);
2005 next_edge = false;
2006 }
2007 }
2008 if (u->is_FastLock() && u->as_FastLock()->obj_node()->eqv_uncast(obj)) {
2009 FastLockNode* flock = u->as_FastLock();
2010 assert(flock->box_node() == oldbox, "sanity");
2011 _igvn.rehash_node_delayed(flock);
2012 flock->set_box_node(newbox);
2013 next_edge = false;
2014 }
2015
2016 // Replace old box in monitor debug info.
2017 if (u->is_SafePoint() && u->as_SafePoint()->jvms()) {
2018 SafePointNode* sfn = u->as_SafePoint();
2019 JVMState* youngest_jvms = sfn->jvms();
2020 int max_depth = youngest_jvms->depth();
2021 for (int depth = 1; depth <= max_depth; depth++) {
2022 JVMState* jvms = youngest_jvms->of_depth(depth);
2023 int num_mon = jvms->nof_monitors();
2024 // Loop over monitors
2025 for (int idx = 0; idx < num_mon; idx++) {
2026 Node* obj_node = sfn->monitor_obj(jvms, idx);
2027 Node* box_node = sfn->monitor_box(jvms, idx);
2028 if (box_node == oldbox && obj_node->eqv_uncast(obj)) {
2029 int j = jvms->monitor_box_offset(idx);
2030 _igvn.replace_input_of(u, j, newbox);
2031 next_edge = false;
2032 }
2033 }
2034 }
2035 }
2036 if (next_edge) i++;
2037 }
2038 }
2039
2040 //-----------------------mark_eliminated_locking_nodes-----------------------
2041 void PhaseMacroExpand::mark_eliminated_locking_nodes(AbstractLockNode *alock) {
2042 if (!alock->is_balanced()) {
2043 return; // Can't do any more elimination for this locking region
2044 }
2045 if (EliminateNestedLocks) {
2046 if (alock->is_nested()) {
2047 assert(alock->box_node()->as_BoxLock()->is_eliminated(), "sanity");
2048 return;
2049 } else if (!alock->is_non_esc_obj()) { // Not eliminated or coarsened
2050 // Only Lock node has JVMState needed here.
2051 // Not that preceding claim is documented anywhere else.
2052 if (alock->jvms() != nullptr) {
2053 if (alock->as_Lock()->is_nested_lock_region()) {
2054 // Mark eliminated related nested locks and unlocks.
2055 Node* obj = alock->obj_node();
2056 BoxLockNode* box_node = alock->box_node()->as_BoxLock();
2057 assert(!box_node->is_eliminated(), "should not be marked yet");
2058 // Note: BoxLock node is marked eliminated only here
2059 // and it is used to indicate that all associated lock
2060 // and unlock nodes are marked for elimination.
2061 box_node->set_eliminated(); // Box's hash is always NO_HASH here
2062 for (uint i = 0; i < box_node->outcnt(); i++) {
2063 Node* u = box_node->raw_out(i);
2064 if (u->is_AbstractLock()) {
2065 alock = u->as_AbstractLock();
2066 if (alock->box_node() == box_node) {
2067 // Verify that this Box is referenced only by related locks.
2068 assert(alock->obj_node()->eqv_uncast(obj), "");
2069 // Mark all related locks and unlocks.
2070 #ifdef ASSERT
2071 alock->log_lock_optimization(C, "eliminate_lock_set_nested");
2072 #endif
2073 alock->set_nested();
2074 }
2075 }
2076 }
2077 } else {
2078 #ifdef ASSERT
2079 alock->log_lock_optimization(C, "eliminate_lock_NOT_nested_lock_region");
2080 if (C->log() != nullptr)
2081 alock->as_Lock()->is_nested_lock_region(C); // rerun for debugging output
2082 #endif
2083 }
2084 }
2085 return;
2086 }
2087 // Process locks for non escaping object
2088 assert(alock->is_non_esc_obj(), "");
2089 } // EliminateNestedLocks
2090
2091 if (alock->is_non_esc_obj()) { // Lock is used for non escaping object
2092 // Look for all locks of this object and mark them and
2093 // corresponding BoxLock nodes as eliminated.
2094 Node* obj = alock->obj_node();
2095 for (uint j = 0; j < obj->outcnt(); j++) {
2096 Node* o = obj->raw_out(j);
2097 if (o->is_AbstractLock() &&
2098 o->as_AbstractLock()->obj_node()->eqv_uncast(obj)) {
2099 alock = o->as_AbstractLock();
2100 Node* box = alock->box_node();
2101 // Replace old box node with new eliminated box for all users
2102 // of the same object and mark related locks as eliminated.
2103 mark_eliminated_box(box, obj);
2104 }
2105 }
2106 }
2107 }
2108
2109 // we have determined that this lock/unlock can be eliminated, we simply
2110 // eliminate the node without expanding it.
2111 //
2112 // Note: The membar's associated with the lock/unlock are currently not
2113 // eliminated. This should be investigated as a future enhancement.
2114 //
2115 bool PhaseMacroExpand::eliminate_locking_node(AbstractLockNode *alock) {
2116
2117 if (!alock->is_eliminated()) {
2118 return false;
2119 }
2120 #ifdef ASSERT
2121 if (!alock->is_coarsened()) {
2122 // Check that new "eliminated" BoxLock node is created.
2123 BoxLockNode* oldbox = alock->box_node()->as_BoxLock();
2124 assert(oldbox->is_eliminated(), "should be done already");
2125 }
2126 #endif
2127
2128 alock->log_lock_optimization(C, "eliminate_lock");
2129
2130 #ifndef PRODUCT
2131 if (PrintEliminateLocks) {
2132 tty->print_cr("++++ Eliminated: %d %s '%s'", alock->_idx, (alock->is_Lock() ? "Lock" : "Unlock"), alock->kind_as_string());
2133 }
2134 #endif
2135
2136 Node* mem = alock->in(TypeFunc::Memory);
2137 Node* ctrl = alock->in(TypeFunc::Control);
2138 guarantee(ctrl != nullptr, "missing control projection, cannot replace_node() with null");
2139
2140 alock->extract_projections(&_callprojs, false /*separate_io_proj*/, false /*do_asserts*/);
2141 // There are 2 projections from the lock. The lock node will
2142 // be deleted when its last use is subsumed below.
2143 assert(alock->outcnt() == 2 &&
2144 _callprojs.fallthrough_proj != nullptr &&
2145 _callprojs.fallthrough_memproj != nullptr,
2146 "Unexpected projections from Lock/Unlock");
2147
2148 Node* fallthroughproj = _callprojs.fallthrough_proj;
2149 Node* memproj_fallthrough = _callprojs.fallthrough_memproj;
2150
2151 // The memory projection from a lock/unlock is RawMem
2152 // The input to a Lock is merged memory, so extract its RawMem input
2153 // (unless the MergeMem has been optimized away.)
2154 if (alock->is_Lock()) {
2155 // Search for MemBarAcquireLock node and delete it also.
2156 MemBarNode* membar = fallthroughproj->unique_ctrl_out()->as_MemBar();
2157 assert(membar != nullptr && membar->Opcode() == Op_MemBarAcquireLock, "");
2158 Node* ctrlproj = membar->proj_out(TypeFunc::Control);
2159 Node* memproj = membar->proj_out(TypeFunc::Memory);
2160 _igvn.replace_node(ctrlproj, fallthroughproj);
2161 _igvn.replace_node(memproj, memproj_fallthrough);
2162
2163 // Delete FastLock node also if this Lock node is unique user
2164 // (a loop peeling may clone a Lock node).
2165 Node* flock = alock->as_Lock()->fastlock_node();
2166 if (flock->outcnt() == 1) {
2167 assert(flock->unique_out() == alock, "sanity");
2168 _igvn.replace_node(flock, top());
2169 }
2170 }
2171
2172 // Search for MemBarReleaseLock node and delete it also.
2173 if (alock->is_Unlock() && ctrl->is_Proj() && ctrl->in(0)->is_MemBar()) {
2174 MemBarNode* membar = ctrl->in(0)->as_MemBar();
2175 assert(membar->Opcode() == Op_MemBarReleaseLock &&
2176 mem->is_Proj() && membar == mem->in(0), "");
2177 _igvn.replace_node(fallthroughproj, ctrl);
2178 _igvn.replace_node(memproj_fallthrough, mem);
2179 fallthroughproj = ctrl;
2180 memproj_fallthrough = mem;
2181 ctrl = membar->in(TypeFunc::Control);
2182 mem = membar->in(TypeFunc::Memory);
2183 }
2184
2185 _igvn.replace_node(fallthroughproj, ctrl);
2186 _igvn.replace_node(memproj_fallthrough, mem);
2187 return true;
2188 }
2189
2190
2191 //------------------------------expand_lock_node----------------------
2192 void PhaseMacroExpand::expand_lock_node(LockNode *lock) {
2193
2194 Node* ctrl = lock->in(TypeFunc::Control);
2195 Node* mem = lock->in(TypeFunc::Memory);
2196 Node* obj = lock->obj_node();
2197 Node* box = lock->box_node();
2198 Node* flock = lock->fastlock_node();
2199
2200 assert(!box->as_BoxLock()->is_eliminated(), "sanity");
2201
2202 // Make the merge point
2203 Node *region;
2204 Node *mem_phi;
2205 Node *slow_path;
2206
2207 region = new RegionNode(3);
2208 // create a Phi for the memory state
2209 mem_phi = new PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM);
2210
2211 // Optimize test; set region slot 2
2212 slow_path = opt_bits_test(ctrl, region, 2, flock);
2213 mem_phi->init_req(2, mem);
2214
2215 // Make slow path call
2216 CallNode* call = make_slow_call(lock, OptoRuntime::complete_monitor_enter_Type(),
2217 OptoRuntime::complete_monitor_locking_Java(), nullptr, slow_path,
2218 obj, box, nullptr);
2219
2220 call->extract_projections(&_callprojs, false /*separate_io_proj*/, false /*do_asserts*/);
2221
2222 // Slow path can only throw asynchronous exceptions, which are always
2223 // de-opted. So the compiler thinks the slow-call can never throw an
2224 // exception. If it DOES throw an exception we would need the debug
2225 // info removed first (since if it throws there is no monitor).
2226 assert(_callprojs.fallthrough_ioproj == nullptr && _callprojs.catchall_ioproj == nullptr &&
2227 _callprojs.catchall_memproj == nullptr && _callprojs.catchall_catchproj == nullptr, "Unexpected projection from Lock");
2228
2229 // Capture slow path
2230 // disconnect fall-through projection from call and create a new one
2231 // hook up users of fall-through projection to region
2232 Node *slow_ctrl = _callprojs.fallthrough_proj->clone();
2233 transform_later(slow_ctrl);
2234 _igvn.hash_delete(_callprojs.fallthrough_proj);
2235 _callprojs.fallthrough_proj->disconnect_inputs(C);
2236 region->init_req(1, slow_ctrl);
2237 // region inputs are now complete
2238 transform_later(region);
2239 _igvn.replace_node(_callprojs.fallthrough_proj, region);
2240
2241 Node *memproj = transform_later(new ProjNode(call, TypeFunc::Memory));
2242
2243 mem_phi->init_req(1, memproj);
2244
2245 transform_later(mem_phi);
2246
2247 _igvn.replace_node(_callprojs.fallthrough_memproj, mem_phi);
2248 }
2249
2250 //------------------------------expand_unlock_node----------------------
2251 void PhaseMacroExpand::expand_unlock_node(UnlockNode *unlock) {
2252
2253 Node* ctrl = unlock->in(TypeFunc::Control);
2254 Node* mem = unlock->in(TypeFunc::Memory);
2255 Node* obj = unlock->obj_node();
2256 Node* box = unlock->box_node();
2257
2258 assert(!box->as_BoxLock()->is_eliminated(), "sanity");
2259
2260 // No need for a null check on unlock
2261
2262 // Make the merge point
2263 Node *region;
2264 Node *mem_phi;
2265
2266 region = new RegionNode(3);
2267 // create a Phi for the memory state
2268 mem_phi = new PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM);
2269
2270 FastUnlockNode *funlock = new FastUnlockNode( ctrl, obj, box );
2271 funlock = transform_later( funlock )->as_FastUnlock();
2272 // Optimize test; set region slot 2
2273 Node *slow_path = opt_bits_test(ctrl, region, 2, funlock);
2274 Node *thread = transform_later(new ThreadLocalNode());
2275
2276 CallNode *call = make_slow_call((CallNode *) unlock, OptoRuntime::complete_monitor_exit_Type(),
2277 CAST_FROM_FN_PTR(address, SharedRuntime::complete_monitor_unlocking_C),
2278 "complete_monitor_unlocking_C", slow_path, obj, box, thread);
2279
2280 call->extract_projections(&_callprojs, false /*separate_io_proj*/, false /*do_asserts*/);
2281 assert(_callprojs.fallthrough_ioproj == nullptr && _callprojs.catchall_ioproj == nullptr &&
2282 _callprojs.catchall_memproj == nullptr && _callprojs.catchall_catchproj == nullptr, "Unexpected projection from Lock");
2283
2284 // No exceptions for unlocking
2285 // Capture slow path
2286 // disconnect fall-through projection from call and create a new one
2287 // hook up users of fall-through projection to region
2288 Node *slow_ctrl = _callprojs.fallthrough_proj->clone();
2289 transform_later(slow_ctrl);
2290 _igvn.hash_delete(_callprojs.fallthrough_proj);
2291 _callprojs.fallthrough_proj->disconnect_inputs(C);
2292 region->init_req(1, slow_ctrl);
2293 // region inputs are now complete
2294 transform_later(region);
2295 _igvn.replace_node(_callprojs.fallthrough_proj, region);
2296
2297 Node *memproj = transform_later(new ProjNode(call, TypeFunc::Memory) );
2298 mem_phi->init_req(1, memproj );
2299 mem_phi->init_req(2, mem);
2300 transform_later(mem_phi);
2301
2302 _igvn.replace_node(_callprojs.fallthrough_memproj, mem_phi);
2303 }
2304
2305 void PhaseMacroExpand::expand_subtypecheck_node(SubTypeCheckNode *check) {
2306 assert(check->in(SubTypeCheckNode::Control) == nullptr, "should be pinned");
2307 Node* bol = check->unique_out();
2308 Node* obj_or_subklass = check->in(SubTypeCheckNode::ObjOrSubKlass);
2309 Node* superklass = check->in(SubTypeCheckNode::SuperKlass);
2310 assert(bol->is_Bool() && bol->as_Bool()->_test._test == BoolTest::ne, "unexpected bool node");
2311
2312 for (DUIterator_Last imin, i = bol->last_outs(imin); i >= imin; --i) {
2313 Node* iff = bol->last_out(i);
2314 assert(iff->is_If(), "where's the if?");
2315
2316 if (iff->in(0)->is_top()) {
2317 _igvn.replace_input_of(iff, 1, C->top());
2318 continue;
2319 }
2320
2321 Node* iftrue = iff->as_If()->proj_out(1);
2322 Node* iffalse = iff->as_If()->proj_out(0);
2323 Node* ctrl = iff->in(0);
2324
2325 Node* subklass = nullptr;
2326 if (_igvn.type(obj_or_subklass)->isa_klassptr()) {
2327 subklass = obj_or_subklass;
2328 } else {
2329 Node* k_adr = basic_plus_adr(obj_or_subklass, Type::klass_offset());
2330 subklass = _igvn.transform(LoadKlassNode::make(_igvn, C->immutable_memory(), k_adr, TypeInstPtr::KLASS));
2331 }
2332
2333 Node* not_subtype_ctrl = Phase::gen_subtype_check(subklass, superklass, &ctrl, nullptr, _igvn, check->method(), check->bci());
2334
2335 _igvn.replace_input_of(iff, 0, C->top());
2336 _igvn.replace_node(iftrue, not_subtype_ctrl);
2337 _igvn.replace_node(iffalse, ctrl);
2338 }
2339 _igvn.replace_node(check, C->top());
2340 }
2341
2342 // Perform refining of strip mined loop nodes in the macro nodes list.
2343 void PhaseMacroExpand::refine_strip_mined_loop_macro_nodes() {
2344 for (int i = C->macro_count(); i > 0; i--) {
2345 Node* n = C->macro_node(i - 1);
2346 if (n->is_OuterStripMinedLoop()) {
2347 n->as_OuterStripMinedLoop()->adjust_strip_mined_loop(&_igvn);
2348 }
2349 }
2350 }
2351
2352 //---------------------------eliminate_macro_nodes----------------------
2353 // Eliminate scalar replaced allocations and associated locks.
2354 void PhaseMacroExpand::eliminate_macro_nodes() {
2355 if (C->macro_count() == 0)
2356 return;
2357
2358 if (StressMacroElimination) {
2359 C->shuffle_macro_nodes();
2360 }
2361 NOT_PRODUCT(int membar_before = count_MemBar(C);)
2362
2363 // Before elimination may re-mark (change to Nested or NonEscObj)
2364 // all associated (same box and obj) lock and unlock nodes.
2365 int cnt = C->macro_count();
2366 for (int i=0; i < cnt; i++) {
2367 Node *n = C->macro_node(i);
2368 if (n->is_AbstractLock()) { // Lock and Unlock nodes
2369 mark_eliminated_locking_nodes(n->as_AbstractLock());
2370 }
2371 }
2372 // Re-marking may break consistency of Coarsened locks.
2373 if (!C->coarsened_locks_consistent()) {
2374 return; // recompile without Coarsened locks if broken
2375 } else {
2376 // After coarsened locks are eliminated locking regions
2377 // become unbalanced. We should not execute any more
2378 // locks elimination optimizations on them.
2379 C->mark_unbalanced_boxes();
2380 }
2381
2382 // First, attempt to eliminate locks
2383 bool progress = true;
2384 while (progress) {
2385 progress = false;
2386 for (int i = C->macro_count(); i > 0; i = MIN2(i - 1, C->macro_count())) { // more than 1 element can be eliminated at once
2387 Node* n = C->macro_node(i - 1);
2388 bool success = false;
2389 DEBUG_ONLY(int old_macro_count = C->macro_count();)
2390 if (n->is_AbstractLock()) {
2391 success = eliminate_locking_node(n->as_AbstractLock());
2392 #ifndef PRODUCT
2393 if (success && PrintOptoStatistics) {
2394 Atomic::inc(&PhaseMacroExpand::_monitor_objects_removed_counter);
2395 }
2396 #endif
2397 }
2398 assert(success == (C->macro_count() < old_macro_count), "elimination reduces macro count");
2399 progress = progress || success;
2400 if (success) {
2401 C->print_method(PHASE_AFTER_MACRO_ELIMINATION_STEP, 5, n);
2402 }
2403 }
2404 }
2405 // Next, attempt to eliminate allocations
2406 progress = true;
2407 while (progress) {
2408 progress = false;
2409 for (int i = C->macro_count(); i > 0; i = MIN2(i - 1, C->macro_count())) { // more than 1 element can be eliminated at once
2410 Node* n = C->macro_node(i - 1);
2411 bool success = false;
2412 DEBUG_ONLY(int old_macro_count = C->macro_count();)
2413 switch (n->class_id()) {
2414 case Node::Class_Allocate:
2415 case Node::Class_AllocateArray:
2416 success = eliminate_allocate_node(n->as_Allocate());
2417 #ifndef PRODUCT
2418 if (success && PrintOptoStatistics) {
2419 Atomic::inc(&PhaseMacroExpand::_objs_scalar_replaced_counter);
2420 }
2421 #endif
2422 break;
2423 case Node::Class_CallStaticJava:
2424 success = eliminate_boxing_node(n->as_CallStaticJava());
2425 break;
2426 case Node::Class_Lock:
2427 case Node::Class_Unlock:
2428 assert(!n->as_AbstractLock()->is_eliminated(), "sanity");
2429 break;
2430 case Node::Class_ArrayCopy:
2431 break;
2432 case Node::Class_OuterStripMinedLoop:
2433 break;
2434 case Node::Class_SubTypeCheck:
2435 break;
2436 case Node::Class_Opaque1:
2437 break;
2438 default:
2439 assert(n->Opcode() == Op_LoopLimit ||
2440 n->Opcode() == Op_ModD ||
2441 n->Opcode() == Op_ModF ||
2442 n->is_OpaqueNotNull() ||
2443 n->is_OpaqueInitializedAssertionPredicate() ||
2444 n->Opcode() == Op_MaxL ||
2445 n->Opcode() == Op_MinL ||
2446 BarrierSet::barrier_set()->barrier_set_c2()->is_gc_barrier_node(n),
2447 "unknown node type in macro list");
2448 }
2449 assert(success == (C->macro_count() < old_macro_count), "elimination reduces macro count");
2450 progress = progress || success;
2451 if (success) {
2452 C->print_method(PHASE_AFTER_MACRO_ELIMINATION_STEP, 5, n);
2453 }
2454 }
2455 }
2456 #ifndef PRODUCT
2457 if (PrintOptoStatistics) {
2458 int membar_after = count_MemBar(C);
2459 Atomic::add(&PhaseMacroExpand::_memory_barriers_removed_counter, membar_before - membar_after);
2460 }
2461 #endif
2462 }
2463
2464 void PhaseMacroExpand::eliminate_opaque_looplimit_macro_nodes() {
2465 if (C->macro_count() == 0) {
2466 return;
2467 }
2468 refine_strip_mined_loop_macro_nodes();
2469 // Eliminate Opaque and LoopLimit nodes. Do it after all loop optimizations.
2470 bool progress = true;
2471 while (progress) {
2472 progress = false;
2473 for (int i = C->macro_count(); i > 0; i--) {
2474 Node* n = C->macro_node(i-1);
2475 bool success = false;
2476 DEBUG_ONLY(int old_macro_count = C->macro_count();)
2477 if (n->Opcode() == Op_LoopLimit) {
2478 // Remove it from macro list and put on IGVN worklist to optimize.
2479 C->remove_macro_node(n);
2480 _igvn._worklist.push(n);
2481 success = true;
2482 } else if (n->Opcode() == Op_CallStaticJava) {
2483 // Remove it from macro list and put on IGVN worklist to optimize.
2484 C->remove_macro_node(n);
2485 _igvn._worklist.push(n);
2486 success = true;
2487 } else if (n->is_Opaque1()) {
2488 _igvn.replace_node(n, n->in(1));
2489 success = true;
2490 } else if (n->is_OpaqueNotNull()) {
2491 // Tests with OpaqueNotNull nodes are implicitly known to be true. Replace the node with true. In debug builds,
2492 // we leave the test in the graph to have an additional sanity check at runtime. If the test fails (i.e. a bug),
2493 // we will execute a Halt node.
2494 #ifdef ASSERT
2495 _igvn.replace_node(n, n->in(1));
2496 #else
2497 _igvn.replace_node(n, _igvn.intcon(1));
2498 #endif
2499 success = true;
2500 } else if (n->is_OpaqueInitializedAssertionPredicate()) {
2501 // Initialized Assertion Predicates must always evaluate to true. Therefore, we get rid of them in product
2502 // builds as they are useless. In debug builds we keep them as additional verification code. Even though
2503 // loop opts are already over, we want to keep Initialized Assertion Predicates alive as long as possible to
2504 // enable folding of dead control paths within which cast nodes become top after due to impossible types -
2505 // even after loop opts are over. Therefore, we delay the removal of these opaque nodes until now.
2506 #ifdef ASSERT
2507 _igvn.replace_node(n, n->in(1));
2508 #else
2509 _igvn.replace_node(n, _igvn.intcon(1));
2510 #endif // ASSERT
2511 } else if (n->Opcode() == Op_OuterStripMinedLoop) {
2512 C->remove_macro_node(n);
2513 success = true;
2514 } else if (n->Opcode() == Op_MaxL) {
2515 // Since MaxL and MinL are not implemented in the backend, we expand them to
2516 // a CMoveL construct now. At least until here, the type could be computed
2517 // precisely. CMoveL is not so smart, but we can give it at least the best
2518 // type we know abouot n now.
2519 Node* repl = MaxNode::signed_max(n->in(1), n->in(2), _igvn.type(n), _igvn);
2520 _igvn.replace_node(n, repl);
2521 success = true;
2522 } else if (n->Opcode() == Op_MinL) {
2523 Node* repl = MaxNode::signed_min(n->in(1), n->in(2), _igvn.type(n), _igvn);
2524 _igvn.replace_node(n, repl);
2525 success = true;
2526 }
2527 assert(!success || (C->macro_count() == (old_macro_count - 1)), "elimination must have deleted one node from macro list");
2528 progress = progress || success;
2529 if (success) {
2530 C->print_method(PHASE_AFTER_MACRO_ELIMINATION_STEP, 5, n);
2531 }
2532 }
2533 }
2534 }
2535
2536 //------------------------------expand_macro_nodes----------------------
2537 // Returns true if a failure occurred.
2538 bool PhaseMacroExpand::expand_macro_nodes() {
2539 if (StressMacroExpansion) {
2540 C->shuffle_macro_nodes();
2541 }
2542
2543 // Clean up the graph so we're less likely to hit the maximum node
2544 // limit
2545 _igvn.set_delay_transform(false);
2546 _igvn.optimize();
2547 if (C->failing()) return true;
2548 _igvn.set_delay_transform(true);
2549
2550
2551 // Because we run IGVN after each expansion, some macro nodes may go
2552 // dead and be removed from the list as we iterate over it. Move
2553 // Allocate nodes (processed in a second pass) at the beginning of
2554 // the list and then iterate from the last element of the list until
2555 // an Allocate node is seen. This is robust to random deletion in
2556 // the list due to nodes going dead.
2557 C->sort_macro_nodes();
2558
2559 // expand arraycopy "macro" nodes first
2560 // For ReduceBulkZeroing, we must first process all arraycopy nodes
2561 // before the allocate nodes are expanded.
2562 while (C->macro_count() > 0) {
2563 int macro_count = C->macro_count();
2564 Node * n = C->macro_node(macro_count-1);
2565 assert(n->is_macro(), "only macro nodes expected here");
2566 if (_igvn.type(n) == Type::TOP || (n->in(0) != nullptr && n->in(0)->is_top())) {
2567 // node is unreachable, so don't try to expand it
2568 C->remove_macro_node(n);
2569 continue;
2570 }
2571 if (n->is_Allocate()) {
2572 break;
2573 }
2574 // Make sure expansion will not cause node limit to be exceeded.
2575 // Worst case is a macro node gets expanded into about 200 nodes.
2576 // Allow 50% more for optimization.
2577 if (C->check_node_count(300, "out of nodes before macro expansion")) {
2578 return true;
2579 }
2580
2581 DEBUG_ONLY(int old_macro_count = C->macro_count();)
2582 switch (n->class_id()) {
2583 case Node::Class_Lock:
2584 expand_lock_node(n->as_Lock());
2585 break;
2586 case Node::Class_Unlock:
2587 expand_unlock_node(n->as_Unlock());
2588 break;
2589 case Node::Class_ArrayCopy:
2590 expand_arraycopy_node(n->as_ArrayCopy());
2591 break;
2592 case Node::Class_SubTypeCheck:
2593 expand_subtypecheck_node(n->as_SubTypeCheck());
2594 break;
2595 default:
2596 switch (n->Opcode()) {
2597 case Op_ModD:
2598 case Op_ModF: {
2599 bool is_drem = n->Opcode() == Op_ModD;
2600 CallNode* mod_macro = n->as_Call();
2601 CallNode* call = new CallLeafNode(mod_macro->tf(),
2602 is_drem ? CAST_FROM_FN_PTR(address, SharedRuntime::drem)
2603 : CAST_FROM_FN_PTR(address, SharedRuntime::frem),
2604 is_drem ? "drem" : "frem", TypeRawPtr::BOTTOM);
2605 call->init_req(TypeFunc::Control, mod_macro->in(TypeFunc::Control));
2606 call->init_req(TypeFunc::I_O, mod_macro->in(TypeFunc::I_O));
2607 call->init_req(TypeFunc::Memory, mod_macro->in(TypeFunc::Memory));
2608 call->init_req(TypeFunc::ReturnAdr, mod_macro->in(TypeFunc::ReturnAdr));
2609 call->init_req(TypeFunc::FramePtr, mod_macro->in(TypeFunc::FramePtr));
2610 for (unsigned int i = 0; i < mod_macro->tf()->domain()->cnt() - TypeFunc::Parms; i++) {
2611 call->init_req(TypeFunc::Parms + i, mod_macro->in(TypeFunc::Parms + i));
2612 }
2613 _igvn.replace_node(mod_macro, call);
2614 transform_later(call);
2615 break;
2616 }
2617 default:
2618 assert(false, "unknown node type in macro list");
2619 }
2620 }
2621 assert(C->macro_count() == (old_macro_count - 1), "expansion must have deleted one node from macro list");
2622 if (C->failing()) return true;
2623 C->print_method(PHASE_AFTER_MACRO_EXPANSION_STEP, 5, n);
2624
2625 // Clean up the graph so we're less likely to hit the maximum node
2626 // limit
2627 _igvn.set_delay_transform(false);
2628 _igvn.optimize();
2629 if (C->failing()) return true;
2630 _igvn.set_delay_transform(true);
2631 }
2632
2633 // All nodes except Allocate nodes are expanded now. There could be
2634 // new optimization opportunities (such as folding newly created
2635 // load from a just allocated object). Run IGVN.
2636
2637 // expand "macro" nodes
2638 // nodes are removed from the macro list as they are processed
2639 while (C->macro_count() > 0) {
2640 int macro_count = C->macro_count();
2641 Node * n = C->macro_node(macro_count-1);
2642 assert(n->is_macro(), "only macro nodes expected here");
2643 if (_igvn.type(n) == Type::TOP || (n->in(0) != nullptr && n->in(0)->is_top())) {
2644 // node is unreachable, so don't try to expand it
2645 C->remove_macro_node(n);
2646 continue;
2647 }
2648 // Make sure expansion will not cause node limit to be exceeded.
2649 // Worst case is a macro node gets expanded into about 200 nodes.
2650 // Allow 50% more for optimization.
2651 if (C->check_node_count(300, "out of nodes before macro expansion")) {
2652 return true;
2653 }
2654 switch (n->class_id()) {
2655 case Node::Class_Allocate:
2656 expand_allocate(n->as_Allocate());
2657 break;
2658 case Node::Class_AllocateArray:
2659 expand_allocate_array(n->as_AllocateArray());
2660 break;
2661 default:
2662 assert(false, "unknown node type in macro list");
2663 }
2664 assert(C->macro_count() < macro_count, "must have deleted a node from macro list");
2665 if (C->failing()) return true;
2666 C->print_method(PHASE_AFTER_MACRO_EXPANSION_STEP, 5, n);
2667
2668 // Clean up the graph so we're less likely to hit the maximum node
2669 // limit
2670 _igvn.set_delay_transform(false);
2671 _igvn.optimize();
2672 if (C->failing()) return true;
2673 _igvn.set_delay_transform(true);
2674 }
2675
2676 _igvn.set_delay_transform(false);
2677 return false;
2678 }
2679
2680 #ifndef PRODUCT
2681 int PhaseMacroExpand::_objs_scalar_replaced_counter = 0;
2682 int PhaseMacroExpand::_monitor_objects_removed_counter = 0;
2683 int PhaseMacroExpand::_GC_barriers_removed_counter = 0;
2684 int PhaseMacroExpand::_memory_barriers_removed_counter = 0;
2685
2686 void PhaseMacroExpand::print_statistics() {
2687 tty->print("Objects scalar replaced = %d, ", Atomic::load(&_objs_scalar_replaced_counter));
2688 tty->print("Monitor objects removed = %d, ", Atomic::load(&_monitor_objects_removed_counter));
2689 tty->print("GC barriers removed = %d, ", Atomic::load(&_GC_barriers_removed_counter));
2690 tty->print_cr("Memory barriers removed = %d", Atomic::load(&_memory_barriers_removed_counter));
2691 }
2692
2693 int PhaseMacroExpand::count_MemBar(Compile *C) {
2694 if (!PrintOptoStatistics) {
2695 return 0;
2696 }
2697 Unique_Node_List ideal_nodes;
2698 int total = 0;
2699 ideal_nodes.map(C->live_nodes(), nullptr);
2700 ideal_nodes.push(C->root());
2701 for (uint next = 0; next < ideal_nodes.size(); ++next) {
2702 Node* n = ideal_nodes.at(next);
2703 if (n->is_MemBar()) {
2704 total++;
2705 }
2706 for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
2707 Node* m = n->fast_out(i);
2708 ideal_nodes.push(m);
2709 }
2710 }
2711 return total;
2712 }
2713 #endif