1 /*
2 * Copyright (c) 2005, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "compiler/compileLog.hpp"
27 #include "gc/shared/collectedHeap.inline.hpp"
28 #include "libadt/vectset.hpp"
29 #include "opto/addnode.hpp"
30 #include "opto/arraycopynode.hpp"
31 #include "opto/callnode.hpp"
32 #include "opto/castnode.hpp"
33 #include "opto/cfgnode.hpp"
34 #include "opto/compile.hpp"
35 #include "opto/convertnode.hpp"
36 #include "opto/graphKit.hpp"
37 #include "opto/locknode.hpp"
38 #include "opto/loopnode.hpp"
39 #include "opto/macro.hpp"
40 #include "opto/memnode.hpp"
41 #include "opto/narrowptrnode.hpp"
42 #include "opto/node.hpp"
43 #include "opto/opaquenode.hpp"
44 #include "opto/phaseX.hpp"
45 #include "opto/rootnode.hpp"
46 #include "opto/runtime.hpp"
47 #include "opto/subnode.hpp"
48 #include "opto/type.hpp"
49 #include "runtime/sharedRuntime.hpp"
50 #include "utilities/macros.hpp"
51 #if INCLUDE_G1GC
52 #include "gc/g1/g1ThreadLocalData.hpp"
53 #endif // INCLUDE_G1GC
54 #if INCLUDE_SHENANDOAHGC
55 #include "gc/shenandoah/c2/shenandoahBarrierSetC2.hpp"
56 #endif
57
58
59 //
60 // Replace any references to "oldref" in inputs to "use" with "newref".
61 // Returns the number of replacements made.
62 //
63 int PhaseMacroExpand::replace_input(Node *use, Node *oldref, Node *newref) {
64 int nreplacements = 0;
65 uint req = use->req();
66 for (uint j = 0; j < use->len(); j++) {
67 Node *uin = use->in(j);
68 if (uin == oldref) {
69 if (j < req)
70 use->set_req(j, newref);
71 else
72 use->set_prec(j, newref);
73 nreplacements++;
74 } else if (j >= req && uin == NULL) {
75 break;
76 }
77 }
78 return nreplacements;
79 }
80
81 void PhaseMacroExpand::copy_call_debug_info(CallNode *oldcall, CallNode * newcall) {
82 // Copy debug information and adjust JVMState information
83 uint old_dbg_start = oldcall->tf()->domain()->cnt();
84 uint new_dbg_start = newcall->tf()->domain()->cnt();
85 int jvms_adj = new_dbg_start - old_dbg_start;
86 assert (new_dbg_start == newcall->req(), "argument count mismatch");
87
88 // SafePointScalarObject node could be referenced several times in debug info.
89 // Use Dict to record cloned nodes.
90 Dict* sosn_map = new Dict(cmpkey,hashkey);
91 for (uint i = old_dbg_start; i < oldcall->req(); i++) {
92 Node* old_in = oldcall->in(i);
93 // Clone old SafePointScalarObjectNodes, adjusting their field contents.
94 if (old_in != NULL && old_in->is_SafePointScalarObject()) {
95 SafePointScalarObjectNode* old_sosn = old_in->as_SafePointScalarObject();
96 uint old_unique = C->unique();
97 Node* new_in = old_sosn->clone(sosn_map);
98 if (old_unique != C->unique()) { // New node?
99 new_in->set_req(0, C->root()); // reset control edge
100 new_in = transform_later(new_in); // Register new node.
101 }
102 old_in = new_in;
103 }
104 newcall->add_req(old_in);
105 }
106
107 // JVMS may be shared so clone it before we modify it
108 newcall->set_jvms(oldcall->jvms() != NULL ? oldcall->jvms()->clone_deep(C) : NULL);
109 for (JVMState *jvms = newcall->jvms(); jvms != NULL; jvms = jvms->caller()) {
110 jvms->set_map(newcall);
111 jvms->set_locoff(jvms->locoff()+jvms_adj);
112 jvms->set_stkoff(jvms->stkoff()+jvms_adj);
113 jvms->set_monoff(jvms->monoff()+jvms_adj);
114 jvms->set_scloff(jvms->scloff()+jvms_adj);
115 jvms->set_endoff(jvms->endoff()+jvms_adj);
116 }
117 }
118
119 Node* PhaseMacroExpand::opt_bits_test(Node* ctrl, Node* region, int edge, Node* word, int mask, int bits, bool return_fast_path) {
120 Node* cmp;
121 if (mask != 0) {
122 Node* and_node = transform_later(new AndXNode(word, MakeConX(mask)));
123 cmp = transform_later(new CmpXNode(and_node, MakeConX(bits)));
124 } else {
125 cmp = word;
126 }
127 Node* bol = transform_later(new BoolNode(cmp, BoolTest::ne));
128 IfNode* iff = new IfNode( ctrl, bol, PROB_MIN, COUNT_UNKNOWN );
129 transform_later(iff);
130
131 // Fast path taken.
132 Node *fast_taken = transform_later(new IfFalseNode(iff));
133
134 // Fast path not-taken, i.e. slow path
135 Node *slow_taken = transform_later(new IfTrueNode(iff));
136
137 if (return_fast_path) {
138 region->init_req(edge, slow_taken); // Capture slow-control
139 return fast_taken;
140 } else {
141 region->init_req(edge, fast_taken); // Capture fast-control
142 return slow_taken;
143 }
144 }
145
146 //--------------------copy_predefined_input_for_runtime_call--------------------
147 void PhaseMacroExpand::copy_predefined_input_for_runtime_call(Node * ctrl, CallNode* oldcall, CallNode* call) {
148 // Set fixed predefined input arguments
149 call->init_req( TypeFunc::Control, ctrl );
150 call->init_req( TypeFunc::I_O , oldcall->in( TypeFunc::I_O) );
151 call->init_req( TypeFunc::Memory , oldcall->in( TypeFunc::Memory ) ); // ?????
152 call->init_req( TypeFunc::ReturnAdr, oldcall->in( TypeFunc::ReturnAdr ) );
153 call->init_req( TypeFunc::FramePtr, oldcall->in( TypeFunc::FramePtr ) );
154 }
155
156 //------------------------------make_slow_call---------------------------------
157 CallNode* PhaseMacroExpand::make_slow_call(CallNode *oldcall, const TypeFunc* slow_call_type,
158 address slow_call, const char* leaf_name, Node* slow_path,
159 Node* parm0, Node* parm1, Node* parm2) {
160
161 // Slow-path call
162 CallNode *call = leaf_name
163 ? (CallNode*)new CallLeafNode ( slow_call_type, slow_call, leaf_name, TypeRawPtr::BOTTOM )
164 : (CallNode*)new CallStaticJavaNode( slow_call_type, slow_call, OptoRuntime::stub_name(slow_call), oldcall->jvms()->bci(), TypeRawPtr::BOTTOM );
165
166 // Slow path call has no side-effects, uses few values
167 copy_predefined_input_for_runtime_call(slow_path, oldcall, call );
168 if (parm0 != NULL) call->init_req(TypeFunc::Parms+0, parm0);
169 if (parm1 != NULL) call->init_req(TypeFunc::Parms+1, parm1);
170 if (parm2 != NULL) call->init_req(TypeFunc::Parms+2, parm2);
171 copy_call_debug_info(oldcall, call);
172 call->set_cnt(PROB_UNLIKELY_MAG(4)); // Same effect as RC_UNCOMMON.
173 _igvn.replace_node(oldcall, call);
174 transform_later(call);
175
176 return call;
177 }
178
179 void PhaseMacroExpand::extract_call_projections(CallNode *call) {
180 _fallthroughproj = NULL;
181 _fallthroughcatchproj = NULL;
182 _ioproj_fallthrough = NULL;
183 _ioproj_catchall = NULL;
184 _catchallcatchproj = NULL;
185 _memproj_fallthrough = NULL;
186 _memproj_catchall = NULL;
187 _resproj = NULL;
188 for (DUIterator_Fast imax, i = call->fast_outs(imax); i < imax; i++) {
189 ProjNode *pn = call->fast_out(i)->as_Proj();
190 switch (pn->_con) {
191 case TypeFunc::Control:
192 {
193 // For Control (fallthrough) and I_O (catch_all_index) we have CatchProj -> Catch -> Proj
194 _fallthroughproj = pn;
195 DUIterator_Fast jmax, j = pn->fast_outs(jmax);
196 const Node *cn = pn->fast_out(j);
197 if (cn->is_Catch()) {
198 ProjNode *cpn = NULL;
199 for (DUIterator_Fast kmax, k = cn->fast_outs(kmax); k < kmax; k++) {
200 cpn = cn->fast_out(k)->as_Proj();
201 assert(cpn->is_CatchProj(), "must be a CatchProjNode");
202 if (cpn->_con == CatchProjNode::fall_through_index)
203 _fallthroughcatchproj = cpn;
204 else {
205 assert(cpn->_con == CatchProjNode::catch_all_index, "must be correct index.");
206 _catchallcatchproj = cpn;
207 }
208 }
209 }
210 break;
211 }
212 case TypeFunc::I_O:
213 if (pn->_is_io_use)
214 _ioproj_catchall = pn;
215 else
216 _ioproj_fallthrough = pn;
217 break;
218 case TypeFunc::Memory:
219 if (pn->_is_io_use)
220 _memproj_catchall = pn;
221 else
222 _memproj_fallthrough = pn;
223 break;
224 case TypeFunc::Parms:
225 _resproj = pn;
226 break;
227 default:
228 assert(false, "unexpected projection from allocation node.");
229 }
230 }
231
232 }
233
234 void PhaseMacroExpand::eliminate_gc_barrier(Node* p2x) {
235 BarrierSetC2 *bs = BarrierSet::barrier_set()->barrier_set_c2();
236 bs->eliminate_gc_barrier(this, p2x);
237 }
238
239 // Search for a memory operation for the specified memory slice.
240 static Node *scan_mem_chain(Node *mem, int alias_idx, int offset, Node *start_mem, Node *alloc, PhaseGVN *phase) {
241 Node *orig_mem = mem;
242 Node *alloc_mem = alloc->in(TypeFunc::Memory);
243 const TypeOopPtr *tinst = phase->C->get_adr_type(alias_idx)->isa_oopptr();
244 while (true) {
245 if (mem == alloc_mem || mem == start_mem ) {
246 return mem; // hit one of our sentinels
247 } else if (mem->is_MergeMem()) {
248 mem = mem->as_MergeMem()->memory_at(alias_idx);
249 } else if (mem->is_Proj() && mem->as_Proj()->_con == TypeFunc::Memory) {
250 Node *in = mem->in(0);
251 // we can safely skip over safepoints, calls, locks and membars because we
252 // already know that the object is safe to eliminate.
253 if (in->is_Initialize() && in->as_Initialize()->allocation() == alloc) {
254 return in;
255 } else if (in->is_Call()) {
256 CallNode *call = in->as_Call();
257 if (call->may_modify(tinst, phase)) {
258 assert(call->is_ArrayCopy(), "ArrayCopy is the only call node that doesn't make allocation escape");
259 if (call->as_ArrayCopy()->modifies(offset, offset, phase, false)) {
260 return in;
261 }
262 }
263 mem = in->in(TypeFunc::Memory);
264 } else if (in->is_MemBar()) {
265 ArrayCopyNode* ac = NULL;
266 if (ArrayCopyNode::may_modify(tinst, in->as_MemBar(), phase, ac)) {
267 assert(ac != NULL && ac->is_clonebasic(), "Only basic clone is a non escaping clone");
268 return ac;
269 }
270 mem = in->in(TypeFunc::Memory);
271 } else {
272 assert(false, "unexpected projection");
273 }
274 } else if (mem->is_Store()) {
275 const TypePtr* atype = mem->as_Store()->adr_type();
276 int adr_idx = phase->C->get_alias_index(atype);
277 if (adr_idx == alias_idx) {
278 assert(atype->isa_oopptr(), "address type must be oopptr");
279 int adr_offset = atype->offset();
280 uint adr_iid = atype->is_oopptr()->instance_id();
281 // Array elements references have the same alias_idx
282 // but different offset and different instance_id.
283 if (adr_offset == offset && adr_iid == alloc->_idx)
284 return mem;
285 } else {
286 assert(adr_idx == Compile::AliasIdxRaw, "address must match or be raw");
287 }
288 mem = mem->in(MemNode::Memory);
289 } else if (mem->is_ClearArray()) {
290 if (!ClearArrayNode::step_through(&mem, alloc->_idx, phase)) {
291 // Can not bypass initialization of the instance
292 // we are looking.
293 debug_only(intptr_t offset;)
294 assert(alloc == AllocateNode::Ideal_allocation(mem->in(3), phase, offset), "sanity");
295 InitializeNode* init = alloc->as_Allocate()->initialization();
296 // We are looking for stored value, return Initialize node
297 // or memory edge from Allocate node.
298 if (init != NULL)
299 return init;
300 else
301 return alloc->in(TypeFunc::Memory); // It will produce zero value (see callers).
302 }
303 // Otherwise skip it (the call updated 'mem' value).
304 } else if (mem->Opcode() == Op_SCMemProj) {
305 mem = mem->in(0);
306 Node* adr = NULL;
307 if (mem->is_LoadStore()) {
308 adr = mem->in(MemNode::Address);
309 } else {
310 assert(mem->Opcode() == Op_EncodeISOArray ||
311 mem->Opcode() == Op_StrCompressedCopy, "sanity");
312 adr = mem->in(3); // Destination array
313 }
314 const TypePtr* atype = adr->bottom_type()->is_ptr();
315 int adr_idx = phase->C->get_alias_index(atype);
316 if (adr_idx == alias_idx) {
317 DEBUG_ONLY(mem->dump();)
318 assert(false, "Object is not scalar replaceable if a LoadStore node accesses its field");
319 return NULL;
320 }
321 mem = mem->in(MemNode::Memory);
322 } else if (mem->Opcode() == Op_StrInflatedCopy) {
323 Node* adr = mem->in(3); // Destination array
324 const TypePtr* atype = adr->bottom_type()->is_ptr();
325 int adr_idx = phase->C->get_alias_index(atype);
326 if (adr_idx == alias_idx) {
327 DEBUG_ONLY(mem->dump();)
328 assert(false, "Object is not scalar replaceable if a StrInflatedCopy node accesses its field");
329 return NULL;
330 }
331 mem = mem->in(MemNode::Memory);
332 } else {
333 return mem;
334 }
335 assert(mem != orig_mem, "dead memory loop");
336 }
337 }
338
339 // Generate loads from source of the arraycopy for fields of
340 // destination needed at a deoptimization point
341 Node* PhaseMacroExpand::make_arraycopy_load(ArrayCopyNode* ac, intptr_t offset, Node* ctl, Node* mem, BasicType ft, const Type *ftype, AllocateNode *alloc) {
342 BasicType bt = ft;
343 const Type *type = ftype;
344 if (ft == T_NARROWOOP) {
345 bt = T_OBJECT;
346 type = ftype->make_oopptr();
347 }
348 Node* res = NULL;
349 if (ac->is_clonebasic()) {
350 Node* base = ac->in(ArrayCopyNode::Src)->in(AddPNode::Base);
351 Node* adr = _igvn.transform(new AddPNode(base, base, MakeConX(offset)));
352 const TypePtr* adr_type = _igvn.type(base)->is_ptr()->add_offset(offset);
353 res = LoadNode::make(_igvn, ctl, mem, adr, adr_type, type, bt, MemNode::unordered, LoadNode::Pinned);
354 } else {
355 if (ac->modifies(offset, offset, &_igvn, true)) {
356 assert(ac->in(ArrayCopyNode::Dest) == alloc->result_cast(), "arraycopy destination should be allocation's result");
357 uint shift = exact_log2(type2aelembytes(bt));
358 Node* diff = _igvn.transform(new SubINode(ac->in(ArrayCopyNode::SrcPos), ac->in(ArrayCopyNode::DestPos)));
359 #ifdef _LP64
360 diff = _igvn.transform(new ConvI2LNode(diff));
361 #endif
362 diff = _igvn.transform(new LShiftXNode(diff, intcon(shift)));
363
364 Node* off = _igvn.transform(new AddXNode(MakeConX(offset), diff));
365 Node* base = ac->in(ArrayCopyNode::Src);
366 Node* adr = _igvn.transform(new AddPNode(base, base, off));
367 const TypePtr* adr_type = _igvn.type(base)->is_ptr()->add_offset(offset);
368 res = LoadNode::make(_igvn, ctl, mem, adr, adr_type, type, bt, MemNode::unordered, LoadNode::Pinned);
369 }
370 }
371 if (res != NULL) {
372 res = _igvn.transform(res);
373 if (ftype->isa_narrowoop()) {
374 // PhaseMacroExpand::scalar_replacement adds DecodeN nodes
375 res = _igvn.transform(new EncodePNode(res, ftype));
376 }
377 return res;
378 }
379 return NULL;
380 }
381
382 //
383 // Given a Memory Phi, compute a value Phi containing the values from stores
384 // on the input paths.
385 // Note: this function is recursive, its depth is limited by the "level" argument
386 // Returns the computed Phi, or NULL if it cannot compute it.
387 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) {
388 assert(mem->is_Phi(), "sanity");
389 int alias_idx = C->get_alias_index(adr_t);
390 int offset = adr_t->offset();
391 int instance_id = adr_t->instance_id();
392
393 // Check if an appropriate value phi already exists.
394 Node* region = mem->in(0);
395 for (DUIterator_Fast kmax, k = region->fast_outs(kmax); k < kmax; k++) {
396 Node* phi = region->fast_out(k);
397 if (phi->is_Phi() && phi != mem &&
398 phi->as_Phi()->is_same_inst_field(phi_type, (int)mem->_idx, instance_id, alias_idx, offset)) {
399 return phi;
400 }
401 }
402 // Check if an appropriate new value phi already exists.
403 Node* new_phi = value_phis->find(mem->_idx);
404 if (new_phi != NULL)
405 return new_phi;
406
407 if (level <= 0) {
408 return NULL; // Give up: phi tree too deep
409 }
410 Node *start_mem = C->start()->proj_out_or_null(TypeFunc::Memory);
411 Node *alloc_mem = alloc->in(TypeFunc::Memory);
412
413 uint length = mem->req();
414 GrowableArray <Node *> values(length, length, NULL, false);
415
416 // create a new Phi for the value
417 PhiNode *phi = new PhiNode(mem->in(0), phi_type, NULL, mem->_idx, instance_id, alias_idx, offset);
418 transform_later(phi);
419 value_phis->push(phi, mem->_idx);
420
421 for (uint j = 1; j < length; j++) {
422 Node *in = mem->in(j);
423 if (in == NULL || in->is_top()) {
424 values.at_put(j, in);
425 } else {
426 Node *val = scan_mem_chain(in, alias_idx, offset, start_mem, alloc, &_igvn);
427 if (val == start_mem || val == alloc_mem) {
428 // hit a sentinel, return appropriate 0 value
429 values.at_put(j, _igvn.zerocon(ft));
430 continue;
431 }
432 if (val->is_Initialize()) {
433 val = val->as_Initialize()->find_captured_store(offset, type2aelembytes(ft), &_igvn);
434 }
435 if (val == NULL) {
436 return NULL; // can't find a value on this path
437 }
438 if (val == mem) {
439 values.at_put(j, mem);
440 } else if (val->is_Store()) {
441 Node* n = val->in(MemNode::ValueIn);
442 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
443 n = bs->step_over_gc_barrier(n);
444 values.at_put(j, n);
445 } else if(val->is_Proj() && val->in(0) == alloc) {
446 values.at_put(j, _igvn.zerocon(ft));
447 } else if (val->is_Phi()) {
448 val = value_from_mem_phi(val, ft, phi_type, adr_t, alloc, value_phis, level-1);
449 if (val == NULL) {
450 return NULL;
451 }
452 values.at_put(j, val);
453 } else if (val->Opcode() == Op_SCMemProj) {
454 assert(val->in(0)->is_LoadStore() ||
455 val->in(0)->Opcode() == Op_EncodeISOArray ||
456 val->in(0)->Opcode() == Op_StrCompressedCopy, "sanity");
457 assert(false, "Object is not scalar replaceable if a LoadStore node accesses its field");
458 return NULL;
459 } else if (val->is_ArrayCopy()) {
460 Node* res = make_arraycopy_load(val->as_ArrayCopy(), offset, val->in(0), val->in(TypeFunc::Memory), ft, phi_type, alloc);
461 if (res == NULL) {
462 return NULL;
463 }
464 values.at_put(j, res);
465 } else {
466 #ifdef ASSERT
467 val->dump();
468 assert(false, "unknown node on this path");
469 #endif
470 return NULL; // unknown node on this path
471 }
472 }
473 }
474 // Set Phi's inputs
475 for (uint j = 1; j < length; j++) {
476 if (values.at(j) == mem) {
477 phi->init_req(j, phi);
478 } else {
479 phi->init_req(j, values.at(j));
480 }
481 }
482 return phi;
483 }
484
485 // Search the last value stored into the object's field.
486 Node *PhaseMacroExpand::value_from_mem(Node *sfpt_mem, Node *sfpt_ctl, BasicType ft, const Type *ftype, const TypeOopPtr *adr_t, AllocateNode *alloc) {
487 assert(adr_t->is_known_instance_field(), "instance required");
488 int instance_id = adr_t->instance_id();
489 assert((uint)instance_id == alloc->_idx, "wrong allocation");
490
491 int alias_idx = C->get_alias_index(adr_t);
492 int offset = adr_t->offset();
493 Node *start_mem = C->start()->proj_out_or_null(TypeFunc::Memory);
494 Node *alloc_ctrl = alloc->in(TypeFunc::Control);
495 Node *alloc_mem = alloc->in(TypeFunc::Memory);
496 Arena *a = Thread::current()->resource_area();
497 VectorSet visited(a);
498
499
500 bool done = sfpt_mem == alloc_mem;
501 Node *mem = sfpt_mem;
502 while (!done) {
503 if (visited.test_set(mem->_idx)) {
504 return NULL; // found a loop, give up
505 }
506 mem = scan_mem_chain(mem, alias_idx, offset, start_mem, alloc, &_igvn);
507 if (mem == start_mem || mem == alloc_mem) {
508 done = true; // hit a sentinel, return appropriate 0 value
509 } else if (mem->is_Initialize()) {
510 mem = mem->as_Initialize()->find_captured_store(offset, type2aelembytes(ft), &_igvn);
511 if (mem == NULL) {
512 done = true; // Something go wrong.
513 } else if (mem->is_Store()) {
514 const TypePtr* atype = mem->as_Store()->adr_type();
515 assert(C->get_alias_index(atype) == Compile::AliasIdxRaw, "store is correct memory slice");
516 done = true;
517 }
518 } else if (mem->is_Store()) {
519 const TypeOopPtr* atype = mem->as_Store()->adr_type()->isa_oopptr();
520 assert(atype != NULL, "address type must be oopptr");
521 assert(C->get_alias_index(atype) == alias_idx &&
522 atype->is_known_instance_field() && atype->offset() == offset &&
523 atype->instance_id() == instance_id, "store is correct memory slice");
524 done = true;
525 } else if (mem->is_Phi()) {
526 // try to find a phi's unique input
527 Node *unique_input = NULL;
528 Node *top = C->top();
529 for (uint i = 1; i < mem->req(); i++) {
530 Node *n = scan_mem_chain(mem->in(i), alias_idx, offset, start_mem, alloc, &_igvn);
531 if (n == NULL || n == top || n == mem) {
532 continue;
533 } else if (unique_input == NULL) {
534 unique_input = n;
535 } else if (unique_input != n) {
536 unique_input = top;
537 break;
538 }
539 }
540 if (unique_input != NULL && unique_input != top) {
541 mem = unique_input;
542 } else {
543 done = true;
544 }
545 } else if (mem->is_ArrayCopy()) {
546 done = true;
547 } else {
548 assert(false, "unexpected node");
549 }
550 }
551 if (mem != NULL) {
552 if (mem == start_mem || mem == alloc_mem) {
553 // hit a sentinel, return appropriate 0 value
554 return _igvn.zerocon(ft);
555 } else if (mem->is_Store()) {
556 Node* n = mem->in(MemNode::ValueIn);
557 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
558 n = bs->step_over_gc_barrier(n);
559 return n;
560 } else if (mem->is_Phi()) {
561 // attempt to produce a Phi reflecting the values on the input paths of the Phi
562 Node_Stack value_phis(a, 8);
563 Node * phi = value_from_mem_phi(mem, ft, ftype, adr_t, alloc, &value_phis, ValueSearchLimit);
564 if (phi != NULL) {
565 return phi;
566 } else {
567 // Kill all new Phis
568 while(value_phis.is_nonempty()) {
569 Node* n = value_phis.node();
570 _igvn.replace_node(n, C->top());
571 value_phis.pop();
572 }
573 }
574 } else if (mem->is_ArrayCopy()) {
575 Node* ctl = mem->in(0);
576 Node* m = mem->in(TypeFunc::Memory);
577 if (sfpt_ctl->is_Proj() && sfpt_ctl->as_Proj()->is_uncommon_trap_proj(Deoptimization::Reason_none)) {
578 // pin the loads in the uncommon trap path
579 ctl = sfpt_ctl;
580 m = sfpt_mem;
581 }
582 return make_arraycopy_load(mem->as_ArrayCopy(), offset, ctl, m, ft, ftype, alloc);
583 }
584 }
585 // Something go wrong.
586 return NULL;
587 }
588
589 // Check the possibility of scalar replacement.
590 bool PhaseMacroExpand::can_eliminate_allocation(AllocateNode *alloc, GrowableArray <SafePointNode *>& safepoints) {
591 // Scan the uses of the allocation to check for anything that would
592 // prevent us from eliminating it.
593 NOT_PRODUCT( const char* fail_eliminate = NULL; )
594 DEBUG_ONLY( Node* disq_node = NULL; )
595 bool can_eliminate = true;
596
597 Node* res = alloc->result_cast();
598 const TypeOopPtr* res_type = NULL;
599 if (res == NULL) {
600 // All users were eliminated.
601 } else if (!res->is_CheckCastPP()) {
602 NOT_PRODUCT(fail_eliminate = "Allocation does not have unique CheckCastPP";)
603 can_eliminate = false;
604 } else {
605 res_type = _igvn.type(res)->isa_oopptr();
606 if (res_type == NULL) {
607 NOT_PRODUCT(fail_eliminate = "Neither instance or array allocation";)
608 can_eliminate = false;
609 } else if (res_type->isa_aryptr()) {
610 int length = alloc->in(AllocateNode::ALength)->find_int_con(-1);
611 if (length < 0) {
612 NOT_PRODUCT(fail_eliminate = "Array's size is not constant";)
613 can_eliminate = false;
614 }
615 }
616 }
617
618 if (can_eliminate && res != NULL) {
619 for (DUIterator_Fast jmax, j = res->fast_outs(jmax);
620 j < jmax && can_eliminate; j++) {
621 Node* use = res->fast_out(j);
622
623 if (use->is_AddP()) {
624 const TypePtr* addp_type = _igvn.type(use)->is_ptr();
625 int offset = addp_type->offset();
626
627 if (offset == Type::OffsetTop || offset == Type::OffsetBot) {
628 NOT_PRODUCT(fail_eliminate = "Undefined field referrence";)
629 can_eliminate = false;
630 break;
631 }
632 for (DUIterator_Fast kmax, k = use->fast_outs(kmax);
633 k < kmax && can_eliminate; k++) {
634 Node* n = use->fast_out(k);
635 if (!n->is_Store() && n->Opcode() != Op_CastP2X &&
636 SHENANDOAHGC_ONLY((!UseShenandoahGC || !ShenandoahBarrierSetC2::is_shenandoah_wb_pre_call(n)) &&)
637 !(n->is_ArrayCopy() &&
638 n->as_ArrayCopy()->is_clonebasic() &&
639 n->in(ArrayCopyNode::Dest) == use)) {
640 DEBUG_ONLY(disq_node = n;)
641 if (n->is_Load() || n->is_LoadStore()) {
642 NOT_PRODUCT(fail_eliminate = "Field load";)
643 } else {
644 NOT_PRODUCT(fail_eliminate = "Not store field referrence";)
645 }
646 can_eliminate = false;
647 }
648 }
649 } else if (use->is_ArrayCopy() &&
650 (use->as_ArrayCopy()->is_arraycopy_validated() ||
651 use->as_ArrayCopy()->is_copyof_validated() ||
652 use->as_ArrayCopy()->is_copyofrange_validated()) &&
653 use->in(ArrayCopyNode::Dest) == res) {
654 // ok to eliminate
655 } else if (use->is_SafePoint()) {
656 SafePointNode* sfpt = use->as_SafePoint();
657 if (sfpt->is_Call() && sfpt->as_Call()->has_non_debug_use(res)) {
658 // Object is passed as argument.
659 DEBUG_ONLY(disq_node = use;)
660 NOT_PRODUCT(fail_eliminate = "Object is passed as argument";)
661 can_eliminate = false;
662 }
663 Node* sfptMem = sfpt->memory();
664 if (sfptMem == NULL || sfptMem->is_top()) {
665 DEBUG_ONLY(disq_node = use;)
666 NOT_PRODUCT(fail_eliminate = "NULL or TOP memory";)
667 can_eliminate = false;
668 } else {
669 safepoints.append_if_missing(sfpt);
670 }
671 } else if (use->Opcode() != Op_CastP2X) { // CastP2X is used by card mark
672 if (use->is_Phi()) {
673 if (use->outcnt() == 1 && use->unique_out()->Opcode() == Op_Return) {
674 NOT_PRODUCT(fail_eliminate = "Object is return value";)
675 } else {
676 NOT_PRODUCT(fail_eliminate = "Object is referenced by Phi";)
677 }
678 DEBUG_ONLY(disq_node = use;)
679 } else {
680 if (use->Opcode() == Op_Return) {
681 NOT_PRODUCT(fail_eliminate = "Object is return value";)
682 }else {
683 NOT_PRODUCT(fail_eliminate = "Object is referenced by node";)
684 }
685 DEBUG_ONLY(disq_node = use;)
686 }
687 can_eliminate = false;
688 }
689 }
690 }
691
692 #ifndef PRODUCT
693 if (PrintEliminateAllocations) {
694 if (can_eliminate) {
695 tty->print("Scalar ");
696 if (res == NULL)
697 alloc->dump();
698 else
699 res->dump();
700 } else if (alloc->_is_scalar_replaceable) {
701 tty->print("NotScalar (%s)", fail_eliminate);
702 if (res == NULL)
703 alloc->dump();
704 else
705 res->dump();
706 #ifdef ASSERT
707 if (disq_node != NULL) {
708 tty->print(" >>>> ");
709 disq_node->dump();
710 }
711 #endif /*ASSERT*/
712 }
713 }
714 #endif
715 return can_eliminate;
716 }
717
718 // Do scalar replacement.
719 bool PhaseMacroExpand::scalar_replacement(AllocateNode *alloc, GrowableArray <SafePointNode *>& safepoints) {
720 GrowableArray <SafePointNode *> safepoints_done;
721
722 ciKlass* klass = NULL;
723 ciInstanceKlass* iklass = NULL;
724 int nfields = 0;
725 int array_base = 0;
726 int element_size = 0;
727 BasicType basic_elem_type = T_ILLEGAL;
728 ciType* elem_type = NULL;
729
730 Node* res = alloc->result_cast();
731 assert(res == NULL || res->is_CheckCastPP(), "unexpected AllocateNode result");
732 const TypeOopPtr* res_type = NULL;
733 if (res != NULL) { // Could be NULL when there are no users
734 res_type = _igvn.type(res)->isa_oopptr();
735 }
736
737 if (res != NULL) {
738 klass = res_type->klass();
739 if (res_type->isa_instptr()) {
740 // find the fields of the class which will be needed for safepoint debug information
741 assert(klass->is_instance_klass(), "must be an instance klass.");
742 iklass = klass->as_instance_klass();
743 nfields = iklass->nof_nonstatic_fields();
744 } else {
745 // find the array's elements which will be needed for safepoint debug information
746 nfields = alloc->in(AllocateNode::ALength)->find_int_con(-1);
747 assert(klass->is_array_klass() && nfields >= 0, "must be an array klass.");
748 elem_type = klass->as_array_klass()->element_type();
749 basic_elem_type = elem_type->basic_type();
750 array_base = arrayOopDesc::base_offset_in_bytes(basic_elem_type);
751 element_size = type2aelembytes(basic_elem_type);
752 }
753 }
754 //
755 // Process the safepoint uses
756 //
757 while (safepoints.length() > 0) {
758 SafePointNode* sfpt = safepoints.pop();
759 Node* mem = sfpt->memory();
760 Node* ctl = sfpt->control();
761 assert(sfpt->jvms() != NULL, "missed JVMS");
762 // Fields of scalar objs are referenced only at the end
763 // of regular debuginfo at the last (youngest) JVMS.
764 // Record relative start index.
765 uint first_ind = (sfpt->req() - sfpt->jvms()->scloff());
766 SafePointScalarObjectNode* sobj = new SafePointScalarObjectNode(res_type,
767 #ifdef ASSERT
768 alloc,
769 #endif
770 first_ind, 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 = NULL;
778 if (iklass != NULL) {
779 field = iklass->nonstatic_field_at(j);
780 offset = field->offset();
781 elem_type = field->type();
782 basic_elem_type = field->layout_type();
783 } else {
784 offset = array_base + j * (intptr_t)element_size;
785 }
786
787 const Type *field_type;
788 // The next code is taken from Parse::do_get_xxx().
789 if (basic_elem_type == T_OBJECT || basic_elem_type == T_ARRAY) {
790 if (!elem_type->is_loaded()) {
791 field_type = TypeInstPtr::BOTTOM;
792 } else if (field != NULL && field->is_static_constant()) {
793 // This can happen if the constant oop is non-perm.
794 ciObject* con = field->constant_value().as_object();
795 // Do not "join" in the previous type; it doesn't add value,
796 // and may yield a vacuous result if the field is of interface type.
797 field_type = TypeOopPtr::make_from_constant(con)->isa_oopptr();
798 assert(field_type != NULL, "field singleton type must be consistent");
799 } else {
800 field_type = TypeOopPtr::make_from_klass(elem_type->as_klass());
801 }
802 if (UseCompressedOops) {
803 field_type = field_type->make_narrowoop();
804 basic_elem_type = T_NARROWOOP;
805 }
806 } else {
807 field_type = Type::get_const_basic_type(basic_elem_type);
808 }
809
810 const TypeOopPtr *field_addr_type = res_type->add_offset(offset)->isa_oopptr();
811
812 Node *field_val = value_from_mem(mem, ctl, basic_elem_type, field_type, field_addr_type, alloc);
813 if (field_val == NULL) {
814 // We weren't able to find a value for this field,
815 // give up on eliminating this allocation.
816
817 // Remove any extra entries we added to the safepoint.
818 uint last = sfpt->req() - 1;
819 for (int k = 0; k < j; k++) {
820 sfpt->del_req(last--);
821 }
822 _igvn._worklist.push(sfpt);
823 // rollback processed safepoints
824 while (safepoints_done.length() > 0) {
825 SafePointNode* sfpt_done = safepoints_done.pop();
826 // remove any extra entries we added to the safepoint
827 last = sfpt_done->req() - 1;
828 for (int k = 0; k < nfields; k++) {
829 sfpt_done->del_req(last--);
830 }
831 JVMState *jvms = sfpt_done->jvms();
832 jvms->set_endoff(sfpt_done->req());
833 // Now make a pass over the debug information replacing any references
834 // to SafePointScalarObjectNode with the allocated object.
835 int start = jvms->debug_start();
836 int end = jvms->debug_end();
837 for (int i = start; i < end; i++) {
838 if (sfpt_done->in(i)->is_SafePointScalarObject()) {
839 SafePointScalarObjectNode* scobj = sfpt_done->in(i)->as_SafePointScalarObject();
840 if (scobj->first_index(jvms) == sfpt_done->req() &&
841 scobj->n_fields() == (uint)nfields) {
842 assert(scobj->alloc() == alloc, "sanity");
843 sfpt_done->set_req(i, res);
844 }
845 }
846 }
847 _igvn._worklist.push(sfpt_done);
848 }
849 #ifndef PRODUCT
850 if (PrintEliminateAllocations) {
851 if (field != NULL) {
852 tty->print("=== At SafePoint node %d can't find value of Field: ",
853 sfpt->_idx);
854 field->print();
855 int field_idx = C->get_alias_index(field_addr_type);
856 tty->print(" (alias_idx=%d)", field_idx);
857 } else { // Array's element
858 tty->print("=== At SafePoint node %d can't find value of array element [%d]",
859 sfpt->_idx, j);
860 }
861 tty->print(", which prevents elimination of: ");
862 if (res == NULL)
863 alloc->dump();
864 else
865 res->dump();
866 }
867 #endif
868 return false;
869 }
870 if (UseCompressedOops && field_type->isa_narrowoop()) {
871 // Enable "DecodeN(EncodeP(Allocate)) --> Allocate" transformation
872 // to be able scalar replace the allocation.
873 if (field_val->is_EncodeP()) {
874 field_val = field_val->in(1);
875 } else {
876 field_val = transform_later(new DecodeNNode(field_val, field_val->get_ptr_type()));
877 }
878 }
879 sfpt->add_req(field_val);
880 }
881 JVMState *jvms = sfpt->jvms();
882 jvms->set_endoff(sfpt->req());
883 // Now make a pass over the debug information replacing any references
884 // to the allocated object with "sobj"
885 int start = jvms->debug_start();
886 int end = jvms->debug_end();
887 sfpt->replace_edges_in_range(res, sobj, start, end);
888 _igvn._worklist.push(sfpt);
889 safepoints_done.append_if_missing(sfpt); // keep it for rollback
890 }
891 return true;
892 }
893
894 static void disconnect_projections(MultiNode* n, PhaseIterGVN& igvn) {
895 Node* ctl_proj = n->proj_out_or_null(TypeFunc::Control);
896 Node* mem_proj = n->proj_out_or_null(TypeFunc::Memory);
897 if (ctl_proj != NULL) {
898 igvn.replace_node(ctl_proj, n->in(0));
899 }
900 if (mem_proj != NULL) {
901 igvn.replace_node(mem_proj, n->in(TypeFunc::Memory));
902 }
903 }
904
905 // Process users of eliminated allocation.
906 void PhaseMacroExpand::process_users_of_allocation(CallNode *alloc) {
907 Node* res = alloc->result_cast();
908 if (res != NULL) {
909 for (DUIterator_Last jmin, j = res->last_outs(jmin); j >= jmin; ) {
910 Node *use = res->last_out(j);
911 uint oc1 = res->outcnt();
912
913 if (use->is_AddP()) {
914 for (DUIterator_Last kmin, k = use->last_outs(kmin); k >= kmin; ) {
915 Node *n = use->last_out(k);
916 uint oc2 = use->outcnt();
917 if (n->is_Store()) {
918 #ifdef ASSERT
919 // Verify that there is no dependent MemBarVolatile nodes,
920 // they should be removed during IGVN, see MemBarNode::Ideal().
921 for (DUIterator_Fast pmax, p = n->fast_outs(pmax);
922 p < pmax; p++) {
923 Node* mb = n->fast_out(p);
924 assert(mb->is_Initialize() || !mb->is_MemBar() ||
925 mb->req() <= MemBarNode::Precedent ||
926 mb->in(MemBarNode::Precedent) != n,
927 "MemBarVolatile should be eliminated for non-escaping object");
928 }
929 #endif
930 _igvn.replace_node(n, n->in(MemNode::Memory));
931 } else if (n->is_ArrayCopy()) {
932 // Disconnect ArrayCopy node
933 ArrayCopyNode* ac = n->as_ArrayCopy();
934 assert(ac->is_clonebasic(), "unexpected array copy kind");
935 Node* membar_after = ac->proj_out(TypeFunc::Control)->unique_ctrl_out();
936 disconnect_projections(ac, _igvn);
937 assert(alloc->in(0)->is_Proj() && alloc->in(0)->in(0)->Opcode() == Op_MemBarCPUOrder, "mem barrier expected before allocation");
938 Node* membar_before = alloc->in(0)->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 eliminate_gc_barrier(n);
945 }
946 k -= (oc2 - use->outcnt());
947 }
948 _igvn.remove_dead_node(use);
949 } else if (use->is_ArrayCopy()) {
950 // Disconnect ArrayCopy node
951 ArrayCopyNode* ac = use->as_ArrayCopy();
952 assert(ac->is_arraycopy_validated() ||
953 ac->is_copyof_validated() ||
954 ac->is_copyofrange_validated(), "unsupported");
955 CallProjections callprojs;
956 ac->extract_projections(&callprojs, true);
957
958 _igvn.replace_node(callprojs.fallthrough_ioproj, ac->in(TypeFunc::I_O));
959 _igvn.replace_node(callprojs.fallthrough_memproj, ac->in(TypeFunc::Memory));
960 _igvn.replace_node(callprojs.fallthrough_catchproj, ac->in(TypeFunc::Control));
961
962 // Set control to top. IGVN will remove the remaining projections
963 ac->set_req(0, top());
964 ac->replace_edge(res, top());
965
966 // Disconnect src right away: it can help find new
967 // opportunities for allocation elimination
968 Node* src = ac->in(ArrayCopyNode::Src);
969 ac->replace_edge(src, top());
970 // src can be top at this point if src and dest of the
971 // arraycopy were the same
972 if (src->outcnt() == 0 && !src->is_top()) {
973 _igvn.remove_dead_node(src);
974 }
975
976 _igvn._worklist.push(ac);
977 } else {
978 eliminate_gc_barrier(use);
979 }
980 j -= (oc1 - res->outcnt());
981 }
982 assert(res->outcnt() == 0, "all uses of allocated objects must be deleted");
983 _igvn.remove_dead_node(res);
984 }
985
986 //
987 // Process other users of allocation's projections
988 //
989 if (_resproj != NULL && _resproj->outcnt() != 0) {
990 // First disconnect stores captured by Initialize node.
991 // If Initialize node is eliminated first in the following code,
992 // it will kill such stores and DUIterator_Last will assert.
993 for (DUIterator_Fast jmax, j = _resproj->fast_outs(jmax); j < jmax; j++) {
994 Node *use = _resproj->fast_out(j);
995 if (use->is_AddP()) {
996 // raw memory addresses used only by the initialization
997 _igvn.replace_node(use, C->top());
998 --j; --jmax;
999 }
1000 }
1001 for (DUIterator_Last jmin, j = _resproj->last_outs(jmin); j >= jmin; ) {
1002 Node *use = _resproj->last_out(j);
1003 uint oc1 = _resproj->outcnt();
1004 if (use->is_Initialize()) {
1005 // Eliminate Initialize node.
1006 InitializeNode *init = use->as_Initialize();
1007 assert(init->outcnt() <= 2, "only a control and memory projection expected");
1008 Node *ctrl_proj = init->proj_out_or_null(TypeFunc::Control);
1009 if (ctrl_proj != NULL) {
1010 assert(init->in(TypeFunc::Control) == _fallthroughcatchproj, "allocation control projection");
1011 _igvn.replace_node(ctrl_proj, _fallthroughcatchproj);
1012 }
1013 Node *mem_proj = init->proj_out_or_null(TypeFunc::Memory);
1014 if (mem_proj != NULL) {
1015 Node *mem = init->in(TypeFunc::Memory);
1016 #ifdef ASSERT
1017 if (mem->is_MergeMem()) {
1018 assert(mem->in(TypeFunc::Memory) == _memproj_fallthrough, "allocation memory projection");
1019 } else {
1020 assert(mem == _memproj_fallthrough, "allocation memory projection");
1021 }
1022 #endif
1023 _igvn.replace_node(mem_proj, mem);
1024 }
1025 } else {
1026 assert(false, "only Initialize or AddP expected");
1027 }
1028 j -= (oc1 - _resproj->outcnt());
1029 }
1030 }
1031 if (_fallthroughcatchproj != NULL) {
1032 _igvn.replace_node(_fallthroughcatchproj, alloc->in(TypeFunc::Control));
1033 }
1034 if (_memproj_fallthrough != NULL) {
1035 _igvn.replace_node(_memproj_fallthrough, alloc->in(TypeFunc::Memory));
1036 }
1037 if (_memproj_catchall != NULL) {
1038 _igvn.replace_node(_memproj_catchall, C->top());
1039 }
1040 if (_ioproj_fallthrough != NULL) {
1041 _igvn.replace_node(_ioproj_fallthrough, alloc->in(TypeFunc::I_O));
1042 }
1043 if (_ioproj_catchall != NULL) {
1044 _igvn.replace_node(_ioproj_catchall, C->top());
1045 }
1046 if (_catchallcatchproj != NULL) {
1047 _igvn.replace_node(_catchallcatchproj, C->top());
1048 }
1049 }
1050
1051 bool PhaseMacroExpand::eliminate_allocate_node(AllocateNode *alloc) {
1052 // Don't do scalar replacement if the frame can be popped by JVMTI:
1053 // if reallocation fails during deoptimization we'll pop all
1054 // interpreter frames for this compiled frame and that won't play
1055 // nice with JVMTI popframe.
1056 if (!EliminateAllocations || JvmtiExport::can_pop_frame() || !alloc->_is_non_escaping) {
1057 return false;
1058 }
1059 Node* klass = alloc->in(AllocateNode::KlassNode);
1060 const TypeKlassPtr* tklass = _igvn.type(klass)->is_klassptr();
1061 Node* res = alloc->result_cast();
1062 // Eliminate boxing allocations which are not used
1063 // regardless scalar replacable status.
1064 bool boxing_alloc = C->eliminate_boxing() &&
1065 tklass->klass()->is_instance_klass() &&
1066 tklass->klass()->as_instance_klass()->is_box_klass();
1067 if (!alloc->_is_scalar_replaceable && (!boxing_alloc || (res != NULL))) {
1068 return false;
1069 }
1070
1071 extract_call_projections(alloc);
1072
1073 GrowableArray <SafePointNode *> safepoints;
1074 if (!can_eliminate_allocation(alloc, safepoints)) {
1075 return false;
1076 }
1077
1078 if (!alloc->_is_scalar_replaceable) {
1079 assert(res == NULL, "sanity");
1080 // We can only eliminate allocation if all debug info references
1081 // are already replaced with SafePointScalarObject because
1082 // we can't search for a fields value without instance_id.
1083 if (safepoints.length() > 0) {
1084 return false;
1085 }
1086 }
1087
1088 if (!scalar_replacement(alloc, safepoints)) {
1089 return false;
1090 }
1091
1092 CompileLog* log = C->log();
1093 if (log != NULL) {
1094 log->head("eliminate_allocation type='%d'",
1095 log->identify(tklass->klass()));
1096 JVMState* p = alloc->jvms();
1097 while (p != NULL) {
1098 log->elem("jvms bci='%d' method='%d'", p->bci(), log->identify(p->method()));
1099 p = p->caller();
1100 }
1101 log->tail("eliminate_allocation");
1102 }
1103
1104 process_users_of_allocation(alloc);
1105
1106 #ifndef PRODUCT
1107 if (PrintEliminateAllocations) {
1108 if (alloc->is_AllocateArray())
1109 tty->print_cr("++++ Eliminated: %d AllocateArray", alloc->_idx);
1110 else
1111 tty->print_cr("++++ Eliminated: %d Allocate", alloc->_idx);
1112 }
1113 #endif
1114
1115 return true;
1116 }
1117
1118 bool PhaseMacroExpand::eliminate_boxing_node(CallStaticJavaNode *boxing) {
1119 // EA should remove all uses of non-escaping boxing node.
1120 if (!C->eliminate_boxing() || boxing->proj_out_or_null(TypeFunc::Parms) != NULL) {
1121 return false;
1122 }
1123
1124 assert(boxing->result_cast() == NULL, "unexpected boxing node result");
1125
1126 extract_call_projections(boxing);
1127
1128 const TypeTuple* r = boxing->tf()->range();
1129 assert(r->cnt() > TypeFunc::Parms, "sanity");
1130 const TypeInstPtr* t = r->field_at(TypeFunc::Parms)->isa_instptr();
1131 assert(t != NULL, "sanity");
1132
1133 CompileLog* log = C->log();
1134 if (log != NULL) {
1135 log->head("eliminate_boxing type='%d'",
1136 log->identify(t->klass()));
1137 JVMState* p = boxing->jvms();
1138 while (p != NULL) {
1139 log->elem("jvms bci='%d' method='%d'", p->bci(), log->identify(p->method()));
1140 p = p->caller();
1141 }
1142 log->tail("eliminate_boxing");
1143 }
1144
1145 process_users_of_allocation(boxing);
1146
1147 #ifndef PRODUCT
1148 if (PrintEliminateAllocations) {
1149 tty->print("++++ Eliminated: %d ", boxing->_idx);
1150 boxing->method()->print_short_name(tty);
1151 tty->cr();
1152 }
1153 #endif
1154
1155 return true;
1156 }
1157
1158 //---------------------------set_eden_pointers-------------------------
1159 void PhaseMacroExpand::set_eden_pointers(Node* &eden_top_adr, Node* &eden_end_adr) {
1160 if (UseTLAB) { // Private allocation: load from TLS
1161 Node* thread = transform_later(new ThreadLocalNode());
1162 int tlab_top_offset = in_bytes(JavaThread::tlab_top_offset());
1163 int tlab_end_offset = in_bytes(JavaThread::tlab_end_offset());
1164 eden_top_adr = basic_plus_adr(top()/*not oop*/, thread, tlab_top_offset);
1165 eden_end_adr = basic_plus_adr(top()/*not oop*/, thread, tlab_end_offset);
1166 } else { // Shared allocation: load from globals
1167 CollectedHeap* ch = Universe::heap();
1168 address top_adr = (address)ch->top_addr();
1169 address end_adr = (address)ch->end_addr();
1170 eden_top_adr = makecon(TypeRawPtr::make(top_adr));
1171 eden_end_adr = basic_plus_adr(eden_top_adr, end_adr - top_adr);
1172 }
1173 }
1174
1175
1176 Node* PhaseMacroExpand::make_load(Node* ctl, Node* mem, Node* base, int offset, const Type* value_type, BasicType bt) {
1177 Node* adr = basic_plus_adr(base, offset);
1178 const TypePtr* adr_type = adr->bottom_type()->is_ptr();
1179 Node* value = LoadNode::make(_igvn, ctl, mem, adr, adr_type, value_type, bt, MemNode::unordered);
1180 transform_later(value);
1181 return value;
1182 }
1183
1184
1185 Node* PhaseMacroExpand::make_store(Node* ctl, Node* mem, Node* base, int offset, Node* value, BasicType bt) {
1186 Node* adr = basic_plus_adr(base, offset);
1187 mem = StoreNode::make(_igvn, ctl, mem, adr, NULL, value, bt, MemNode::unordered);
1188 transform_later(mem);
1189 return mem;
1190 }
1191
1192 //=============================================================================
1193 //
1194 // A L L O C A T I O N
1195 //
1196 // Allocation attempts to be fast in the case of frequent small objects.
1197 // It breaks down like this:
1198 //
1199 // 1) Size in doublewords is computed. This is a constant for objects and
1200 // variable for most arrays. Doubleword units are used to avoid size
1201 // overflow of huge doubleword arrays. We need doublewords in the end for
1202 // rounding.
1203 //
1204 // 2) Size is checked for being 'too large'. Too-large allocations will go
1205 // the slow path into the VM. The slow path can throw any required
1206 // exceptions, and does all the special checks for very large arrays. The
1207 // size test can constant-fold away for objects. For objects with
1208 // finalizers it constant-folds the otherway: you always go slow with
1209 // finalizers.
1210 //
1211 // 3) If NOT using TLABs, this is the contended loop-back point.
1212 // Load-Locked the heap top. If using TLABs normal-load the heap top.
1213 //
1214 // 4) Check that heap top + size*8 < max. If we fail go the slow ` route.
1215 // NOTE: "top+size*8" cannot wrap the 4Gig line! Here's why: for largish
1216 // "size*8" we always enter the VM, where "largish" is a constant picked small
1217 // enough that there's always space between the eden max and 4Gig (old space is
1218 // there so it's quite large) and large enough that the cost of entering the VM
1219 // is dwarfed by the cost to initialize the space.
1220 //
1221 // 5) If NOT using TLABs, Store-Conditional the adjusted heap top back
1222 // down. If contended, repeat at step 3. If using TLABs normal-store
1223 // adjusted heap top back down; there is no contention.
1224 //
1225 // 6) If !ZeroTLAB then Bulk-clear the object/array. Fill in klass & mark
1226 // fields.
1227 //
1228 // 7) Merge with the slow-path; cast the raw memory pointer to the correct
1229 // oop flavor.
1230 //
1231 //=============================================================================
1232 // FastAllocateSizeLimit value is in DOUBLEWORDS.
1233 // Allocations bigger than this always go the slow route.
1234 // This value must be small enough that allocation attempts that need to
1235 // trigger exceptions go the slow route. Also, it must be small enough so
1236 // that heap_top + size_in_bytes does not wrap around the 4Gig limit.
1237 //=============================================================================j//
1238 // %%% Here is an old comment from parseHelper.cpp; is it outdated?
1239 // The allocator will coalesce int->oop copies away. See comment in
1240 // coalesce.cpp about how this works. It depends critically on the exact
1241 // code shape produced here, so if you are changing this code shape
1242 // make sure the GC info for the heap-top is correct in and around the
1243 // slow-path call.
1244 //
1245
1246 void PhaseMacroExpand::expand_allocate_common(
1247 AllocateNode* alloc, // allocation node to be expanded
1248 Node* length, // array length for an array allocation
1249 const TypeFunc* slow_call_type, // Type of slow call
1250 address slow_call_address // Address of slow call
1251 )
1252 {
1253
1254 Node* ctrl = alloc->in(TypeFunc::Control);
1255 Node* mem = alloc->in(TypeFunc::Memory);
1256 Node* i_o = alloc->in(TypeFunc::I_O);
1257 Node* size_in_bytes = alloc->in(AllocateNode::AllocSize);
1258 Node* klass_node = alloc->in(AllocateNode::KlassNode);
1259 Node* initial_slow_test = alloc->in(AllocateNode::InitialTest);
1260
1261 assert(ctrl != NULL, "must have control");
1262 // We need a Region and corresponding Phi's to merge the slow-path and fast-path results.
1263 // they will not be used if "always_slow" is set
1264 enum { slow_result_path = 1, fast_result_path = 2 };
1265 Node *result_region = NULL;
1266 Node *result_phi_rawmem = NULL;
1267 Node *result_phi_rawoop = NULL;
1268 Node *result_phi_i_o = NULL;
1269
1270 // The initial slow comparison is a size check, the comparison
1271 // we want to do is a BoolTest::gt
1272 bool always_slow = false;
1273 int tv = _igvn.find_int_con(initial_slow_test, -1);
1274 if (tv >= 0) {
1275 always_slow = (tv == 1);
1276 initial_slow_test = NULL;
1277 } else {
1278 initial_slow_test = BoolNode::make_predicate(initial_slow_test, &_igvn);
1279 }
1280
1281 if (C->env()->dtrace_alloc_probes() ||
1282 (!UseTLAB && !Universe::heap()->supports_inline_contig_alloc())) {
1283 // Force slow-path allocation
1284 always_slow = true;
1285 initial_slow_test = NULL;
1286 }
1287
1288
1289 enum { too_big_or_final_path = 1, need_gc_path = 2 };
1290 Node *slow_region = NULL;
1291 Node *toobig_false = ctrl;
1292
1293 assert (initial_slow_test == NULL || !always_slow, "arguments must be consistent");
1294 // generate the initial test if necessary
1295 if (initial_slow_test != NULL ) {
1296 slow_region = new RegionNode(3);
1297
1298 // Now make the initial failure test. Usually a too-big test but
1299 // might be a TRUE for finalizers or a fancy class check for
1300 // newInstance0.
1301 IfNode *toobig_iff = new IfNode(ctrl, initial_slow_test, PROB_MIN, COUNT_UNKNOWN);
1302 transform_later(toobig_iff);
1303 // Plug the failing-too-big test into the slow-path region
1304 Node *toobig_true = new IfTrueNode( toobig_iff );
1305 transform_later(toobig_true);
1306 slow_region ->init_req( too_big_or_final_path, toobig_true );
1307 toobig_false = new IfFalseNode( toobig_iff );
1308 transform_later(toobig_false);
1309 } else { // No initial test, just fall into next case
1310 toobig_false = ctrl;
1311 debug_only(slow_region = NodeSentinel);
1312 }
1313
1314 Node *slow_mem = mem; // save the current memory state for slow path
1315 // generate the fast allocation code unless we know that the initial test will always go slow
1316 if (!always_slow) {
1317 // Fast path modifies only raw memory.
1318 if (mem->is_MergeMem()) {
1319 mem = mem->as_MergeMem()->memory_at(Compile::AliasIdxRaw);
1320 }
1321
1322 // allocate the Region and Phi nodes for the result
1323 result_region = new RegionNode(3);
1324 result_phi_rawmem = new PhiNode(result_region, Type::MEMORY, TypeRawPtr::BOTTOM);
1325 result_phi_rawoop = new PhiNode(result_region, TypeRawPtr::BOTTOM);
1326 result_phi_i_o = new PhiNode(result_region, Type::ABIO); // I/O is used for Prefetch
1327
1328 // Grab regular I/O before optional prefetch may change it.
1329 // Slow-path does no I/O so just set it to the original I/O.
1330 result_phi_i_o->init_req(slow_result_path, i_o);
1331
1332 Node* needgc_ctrl = NULL;
1333 // Name successful fast-path variables
1334 Node* fast_oop_ctrl;
1335 Node* fast_oop_rawmem;
1336
1337 intx prefetch_lines = length != NULL ? AllocatePrefetchLines : AllocateInstancePrefetchLines;
1338
1339 BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
1340 Node* fast_oop = bs->obj_allocate(this, ctrl, mem, toobig_false, size_in_bytes, i_o, needgc_ctrl,
1341 fast_oop_ctrl, fast_oop_rawmem,
1342 prefetch_lines);
1343
1344 if (initial_slow_test) {
1345 slow_region->init_req(need_gc_path, needgc_ctrl);
1346 // This completes all paths into the slow merge point
1347 transform_later(slow_region);
1348 } else { // No initial slow path needed!
1349 // Just fall from the need-GC path straight into the VM call.
1350 slow_region = needgc_ctrl;
1351 }
1352
1353 InitializeNode* init = alloc->initialization();
1354 fast_oop_rawmem = initialize_object(alloc,
1355 fast_oop_ctrl, fast_oop_rawmem, fast_oop,
1356 klass_node, length, size_in_bytes);
1357
1358 // If initialization is performed by an array copy, any required
1359 // MemBarStoreStore was already added. If the object does not
1360 // escape no need for a MemBarStoreStore. If the object does not
1361 // escape in its initializer and memory barrier (MemBarStoreStore or
1362 // stronger) is already added at exit of initializer, also no need
1363 // for a MemBarStoreStore. Otherwise we need a MemBarStoreStore
1364 // so that stores that initialize this object can't be reordered
1365 // with a subsequent store that makes this object accessible by
1366 // other threads.
1367 // Other threads include java threads and JVM internal threads
1368 // (for example concurrent GC threads). Current concurrent GC
1369 // implementation: CMS and G1 will not scan newly created object,
1370 // so it's safe to skip storestore barrier when allocation does
1371 // not escape.
1372 if (!alloc->does_not_escape_thread() &&
1373 !alloc->is_allocation_MemBar_redundant() &&
1374 (init == NULL || !init->is_complete_with_arraycopy())) {
1375 if (init == NULL || init->req() < InitializeNode::RawStores) {
1376 // No InitializeNode or no stores captured by zeroing
1377 // elimination. Simply add the MemBarStoreStore after object
1378 // initialization.
1379 MemBarNode* mb = MemBarNode::make(C, Op_MemBarStoreStore, Compile::AliasIdxBot);
1380 transform_later(mb);
1381
1382 mb->init_req(TypeFunc::Memory, fast_oop_rawmem);
1383 mb->init_req(TypeFunc::Control, fast_oop_ctrl);
1384 fast_oop_ctrl = new ProjNode(mb,TypeFunc::Control);
1385 transform_later(fast_oop_ctrl);
1386 fast_oop_rawmem = new ProjNode(mb,TypeFunc::Memory);
1387 transform_later(fast_oop_rawmem);
1388 } else {
1389 // Add the MemBarStoreStore after the InitializeNode so that
1390 // all stores performing the initialization that were moved
1391 // before the InitializeNode happen before the storestore
1392 // barrier.
1393
1394 Node* init_ctrl = init->proj_out_or_null(TypeFunc::Control);
1395 Node* init_mem = init->proj_out_or_null(TypeFunc::Memory);
1396
1397 MemBarNode* mb = MemBarNode::make(C, Op_MemBarStoreStore, Compile::AliasIdxBot);
1398 transform_later(mb);
1399
1400 Node* ctrl = new ProjNode(init,TypeFunc::Control);
1401 transform_later(ctrl);
1402 Node* mem = new ProjNode(init,TypeFunc::Memory);
1403 transform_later(mem);
1404
1405 // The MemBarStoreStore depends on control and memory coming
1406 // from the InitializeNode
1407 mb->init_req(TypeFunc::Memory, mem);
1408 mb->init_req(TypeFunc::Control, ctrl);
1409
1410 ctrl = new ProjNode(mb,TypeFunc::Control);
1411 transform_later(ctrl);
1412 mem = new ProjNode(mb,TypeFunc::Memory);
1413 transform_later(mem);
1414
1415 // All nodes that depended on the InitializeNode for control
1416 // and memory must now depend on the MemBarNode that itself
1417 // depends on the InitializeNode
1418 if (init_ctrl != NULL) {
1419 _igvn.replace_node(init_ctrl, ctrl);
1420 }
1421 if (init_mem != NULL) {
1422 _igvn.replace_node(init_mem, mem);
1423 }
1424 }
1425 }
1426
1427 if (C->env()->dtrace_extended_probes()) {
1428 // Slow-path call
1429 int size = TypeFunc::Parms + 2;
1430 CallLeafNode *call = new CallLeafNode(OptoRuntime::dtrace_object_alloc_Type(),
1431 CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_object_alloc_base),
1432 "dtrace_object_alloc",
1433 TypeRawPtr::BOTTOM);
1434
1435 // Get base of thread-local storage area
1436 Node* thread = new ThreadLocalNode();
1437 transform_later(thread);
1438
1439 call->init_req(TypeFunc::Parms+0, thread);
1440 call->init_req(TypeFunc::Parms+1, fast_oop);
1441 call->init_req(TypeFunc::Control, fast_oop_ctrl);
1442 call->init_req(TypeFunc::I_O , top()); // does no i/o
1443 call->init_req(TypeFunc::Memory , fast_oop_rawmem);
1444 call->init_req(TypeFunc::ReturnAdr, alloc->in(TypeFunc::ReturnAdr));
1445 call->init_req(TypeFunc::FramePtr, alloc->in(TypeFunc::FramePtr));
1446 transform_later(call);
1447 fast_oop_ctrl = new ProjNode(call,TypeFunc::Control);
1448 transform_later(fast_oop_ctrl);
1449 fast_oop_rawmem = new ProjNode(call,TypeFunc::Memory);
1450 transform_later(fast_oop_rawmem);
1451 }
1452
1453 // Plug in the successful fast-path into the result merge point
1454 result_region ->init_req(fast_result_path, fast_oop_ctrl);
1455 result_phi_rawoop->init_req(fast_result_path, fast_oop);
1456 result_phi_i_o ->init_req(fast_result_path, i_o);
1457 result_phi_rawmem->init_req(fast_result_path, fast_oop_rawmem);
1458 } else {
1459 slow_region = ctrl;
1460 result_phi_i_o = i_o; // Rename it to use in the following code.
1461 }
1462
1463 // Generate slow-path call
1464 CallNode *call = new CallStaticJavaNode(slow_call_type, slow_call_address,
1465 OptoRuntime::stub_name(slow_call_address),
1466 alloc->jvms()->bci(),
1467 TypePtr::BOTTOM);
1468 call->init_req( TypeFunc::Control, slow_region );
1469 call->init_req( TypeFunc::I_O , top() ) ; // does no i/o
1470 call->init_req( TypeFunc::Memory , slow_mem ); // may gc ptrs
1471 call->init_req( TypeFunc::ReturnAdr, alloc->in(TypeFunc::ReturnAdr) );
1472 call->init_req( TypeFunc::FramePtr, alloc->in(TypeFunc::FramePtr) );
1473
1474 call->init_req(TypeFunc::Parms+0, klass_node);
1475 if (length != NULL) {
1476 call->init_req(TypeFunc::Parms+1, length);
1477 }
1478
1479 // Copy debug information and adjust JVMState information, then replace
1480 // allocate node with the call
1481 copy_call_debug_info((CallNode *) alloc, call);
1482 if (!always_slow) {
1483 call->set_cnt(PROB_UNLIKELY_MAG(4)); // Same effect as RC_UNCOMMON.
1484 } else {
1485 // Hook i_o projection to avoid its elimination during allocation
1486 // replacement (when only a slow call is generated).
1487 call->set_req(TypeFunc::I_O, result_phi_i_o);
1488 }
1489 _igvn.replace_node(alloc, call);
1490 transform_later(call);
1491
1492 // Identify the output projections from the allocate node and
1493 // adjust any references to them.
1494 // The control and io projections look like:
1495 //
1496 // v---Proj(ctrl) <-----+ v---CatchProj(ctrl)
1497 // Allocate Catch
1498 // ^---Proj(io) <-------+ ^---CatchProj(io)
1499 //
1500 // We are interested in the CatchProj nodes.
1501 //
1502 extract_call_projections(call);
1503
1504 // An allocate node has separate memory projections for the uses on
1505 // the control and i_o paths. Replace the control memory projection with
1506 // result_phi_rawmem (unless we are only generating a slow call when
1507 // both memory projections are combined)
1508 if (!always_slow && _memproj_fallthrough != NULL) {
1509 for (DUIterator_Fast imax, i = _memproj_fallthrough->fast_outs(imax); i < imax; i++) {
1510 Node *use = _memproj_fallthrough->fast_out(i);
1511 _igvn.rehash_node_delayed(use);
1512 imax -= replace_input(use, _memproj_fallthrough, result_phi_rawmem);
1513 // back up iterator
1514 --i;
1515 }
1516 }
1517 // Now change uses of _memproj_catchall to use _memproj_fallthrough and delete
1518 // _memproj_catchall so we end up with a call that has only 1 memory projection.
1519 if (_memproj_catchall != NULL ) {
1520 if (_memproj_fallthrough == NULL) {
1521 _memproj_fallthrough = new ProjNode(call, TypeFunc::Memory);
1522 transform_later(_memproj_fallthrough);
1523 }
1524 for (DUIterator_Fast imax, i = _memproj_catchall->fast_outs(imax); i < imax; i++) {
1525 Node *use = _memproj_catchall->fast_out(i);
1526 _igvn.rehash_node_delayed(use);
1527 imax -= replace_input(use, _memproj_catchall, _memproj_fallthrough);
1528 // back up iterator
1529 --i;
1530 }
1531 assert(_memproj_catchall->outcnt() == 0, "all uses must be deleted");
1532 _igvn.remove_dead_node(_memproj_catchall);
1533 }
1534
1535 // An allocate node has separate i_o projections for the uses on the control
1536 // and i_o paths. Always replace the control i_o projection with result i_o
1537 // otherwise incoming i_o become dead when only a slow call is generated
1538 // (it is different from memory projections where both projections are
1539 // combined in such case).
1540 if (_ioproj_fallthrough != NULL) {
1541 for (DUIterator_Fast imax, i = _ioproj_fallthrough->fast_outs(imax); i < imax; i++) {
1542 Node *use = _ioproj_fallthrough->fast_out(i);
1543 _igvn.rehash_node_delayed(use);
1544 imax -= replace_input(use, _ioproj_fallthrough, result_phi_i_o);
1545 // back up iterator
1546 --i;
1547 }
1548 }
1549 // Now change uses of _ioproj_catchall to use _ioproj_fallthrough and delete
1550 // _ioproj_catchall so we end up with a call that has only 1 i_o projection.
1551 if (_ioproj_catchall != NULL ) {
1552 if (_ioproj_fallthrough == NULL) {
1553 _ioproj_fallthrough = new ProjNode(call, TypeFunc::I_O);
1554 transform_later(_ioproj_fallthrough);
1555 }
1556 for (DUIterator_Fast imax, i = _ioproj_catchall->fast_outs(imax); i < imax; i++) {
1557 Node *use = _ioproj_catchall->fast_out(i);
1558 _igvn.rehash_node_delayed(use);
1559 imax -= replace_input(use, _ioproj_catchall, _ioproj_fallthrough);
1560 // back up iterator
1561 --i;
1562 }
1563 assert(_ioproj_catchall->outcnt() == 0, "all uses must be deleted");
1564 _igvn.remove_dead_node(_ioproj_catchall);
1565 }
1566
1567 // if we generated only a slow call, we are done
1568 if (always_slow) {
1569 // Now we can unhook i_o.
1570 if (result_phi_i_o->outcnt() > 1) {
1571 call->set_req(TypeFunc::I_O, top());
1572 } else {
1573 assert(result_phi_i_o->unique_ctrl_out() == call, "");
1574 // Case of new array with negative size known during compilation.
1575 // AllocateArrayNode::Ideal() optimization disconnect unreachable
1576 // following code since call to runtime will throw exception.
1577 // As result there will be no users of i_o after the call.
1578 // Leave i_o attached to this call to avoid problems in preceding graph.
1579 }
1580 return;
1581 }
1582
1583
1584 if (_fallthroughcatchproj != NULL) {
1585 ctrl = _fallthroughcatchproj->clone();
1586 transform_later(ctrl);
1587 _igvn.replace_node(_fallthroughcatchproj, result_region);
1588 } else {
1589 ctrl = top();
1590 }
1591 Node *slow_result;
1592 if (_resproj == NULL) {
1593 // no uses of the allocation result
1594 slow_result = top();
1595 } else {
1596 slow_result = _resproj->clone();
1597 transform_later(slow_result);
1598 _igvn.replace_node(_resproj, result_phi_rawoop);
1599 }
1600
1601 // Plug slow-path into result merge point
1602 result_region ->init_req( slow_result_path, ctrl );
1603 result_phi_rawoop->init_req( slow_result_path, slow_result);
1604 result_phi_rawmem->init_req( slow_result_path, _memproj_fallthrough );
1605 transform_later(result_region);
1606 transform_later(result_phi_rawoop);
1607 transform_later(result_phi_rawmem);
1608 transform_later(result_phi_i_o);
1609 // This completes all paths into the result merge point
1610 }
1611
1612
1613 // Helper for PhaseMacroExpand::expand_allocate_common.
1614 // Initializes the newly-allocated storage.
1615 Node*
1616 PhaseMacroExpand::initialize_object(AllocateNode* alloc,
1617 Node* control, Node* rawmem, Node* object,
1618 Node* klass_node, Node* length,
1619 Node* size_in_bytes) {
1620 InitializeNode* init = alloc->initialization();
1621 // Store the klass & mark bits
1622 Node* mark_node = NULL;
1623 // For now only enable fast locking for non-array types
1624 if (UseBiasedLocking && (length == NULL)) {
1625 mark_node = make_load(control, rawmem, klass_node, in_bytes(Klass::prototype_header_offset()), TypeRawPtr::BOTTOM, T_ADDRESS);
1626 } else {
1627 mark_node = makecon(TypeRawPtr::make((address)markOopDesc::prototype()));
1628 }
1629 rawmem = make_store(control, rawmem, object, oopDesc::mark_offset_in_bytes(), mark_node, T_ADDRESS);
1630
1631 rawmem = make_store(control, rawmem, object, oopDesc::klass_offset_in_bytes(), klass_node, T_METADATA);
1632 int header_size = alloc->minimum_header_size(); // conservatively small
1633
1634 // Array length
1635 if (length != NULL) { // Arrays need length field
1636 rawmem = make_store(control, rawmem, object, arrayOopDesc::length_offset_in_bytes(), length, T_INT);
1637 // conservatively small header size:
1638 header_size = arrayOopDesc::base_offset_in_bytes(T_BYTE);
1639 ciKlass* k = _igvn.type(klass_node)->is_klassptr()->klass();
1640 if (k->is_array_klass()) // we know the exact header size in most cases:
1641 header_size = Klass::layout_helper_header_size(k->layout_helper());
1642 }
1643
1644 // Clear the object body, if necessary.
1645 if (init == NULL) {
1646 // The init has somehow disappeared; be cautious and clear everything.
1647 //
1648 // This can happen if a node is allocated but an uncommon trap occurs
1649 // immediately. In this case, the Initialize gets associated with the
1650 // trap, and may be placed in a different (outer) loop, if the Allocate
1651 // is in a loop. If (this is rare) the inner loop gets unrolled, then
1652 // there can be two Allocates to one Initialize. The answer in all these
1653 // edge cases is safety first. It is always safe to clear immediately
1654 // within an Allocate, and then (maybe or maybe not) clear some more later.
1655 if (!(UseTLAB && ZeroTLAB)) {
1656 rawmem = ClearArrayNode::clear_memory(control, rawmem, object,
1657 header_size, size_in_bytes,
1658 &_igvn);
1659 }
1660 } else {
1661 if (!init->is_complete()) {
1662 // Try to win by zeroing only what the init does not store.
1663 // We can also try to do some peephole optimizations,
1664 // such as combining some adjacent subword stores.
1665 rawmem = init->complete_stores(control, rawmem, object,
1666 header_size, size_in_bytes, &_igvn);
1667 }
1668 // We have no more use for this link, since the AllocateNode goes away:
1669 init->set_req(InitializeNode::RawAddress, top());
1670 // (If we keep the link, it just confuses the register allocator,
1671 // who thinks he sees a real use of the address by the membar.)
1672 }
1673
1674 return rawmem;
1675 }
1676
1677 // Generate prefetch instructions for next allocations.
1678 Node* PhaseMacroExpand::prefetch_allocation(Node* i_o, Node*& needgc_false,
1679 Node*& contended_phi_rawmem,
1680 Node* old_eden_top, Node* new_eden_top,
1681 intx lines) {
1682 enum { fall_in_path = 1, pf_path = 2 };
1683 if( UseTLAB && AllocatePrefetchStyle == 2 ) {
1684 // Generate prefetch allocation with watermark check.
1685 // As an allocation hits the watermark, we will prefetch starting
1686 // at a "distance" away from watermark.
1687
1688 Node *pf_region = new RegionNode(3);
1689 Node *pf_phi_rawmem = new PhiNode( pf_region, Type::MEMORY,
1690 TypeRawPtr::BOTTOM );
1691 // I/O is used for Prefetch
1692 Node *pf_phi_abio = new PhiNode( pf_region, Type::ABIO );
1693
1694 Node *thread = new ThreadLocalNode();
1695 transform_later(thread);
1696
1697 Node *eden_pf_adr = new AddPNode( top()/*not oop*/, thread,
1698 _igvn.MakeConX(in_bytes(JavaThread::tlab_pf_top_offset())) );
1699 transform_later(eden_pf_adr);
1700
1701 Node *old_pf_wm = new LoadPNode(needgc_false,
1702 contended_phi_rawmem, eden_pf_adr,
1703 TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM,
1704 MemNode::unordered);
1705 transform_later(old_pf_wm);
1706
1707 // check against new_eden_top
1708 Node *need_pf_cmp = new CmpPNode( new_eden_top, old_pf_wm );
1709 transform_later(need_pf_cmp);
1710 Node *need_pf_bol = new BoolNode( need_pf_cmp, BoolTest::ge );
1711 transform_later(need_pf_bol);
1712 IfNode *need_pf_iff = new IfNode( needgc_false, need_pf_bol,
1713 PROB_UNLIKELY_MAG(4), COUNT_UNKNOWN );
1714 transform_later(need_pf_iff);
1715
1716 // true node, add prefetchdistance
1717 Node *need_pf_true = new IfTrueNode( need_pf_iff );
1718 transform_later(need_pf_true);
1719
1720 Node *need_pf_false = new IfFalseNode( need_pf_iff );
1721 transform_later(need_pf_false);
1722
1723 Node *new_pf_wmt = new AddPNode( top(), old_pf_wm,
1724 _igvn.MakeConX(AllocatePrefetchDistance) );
1725 transform_later(new_pf_wmt );
1726 new_pf_wmt->set_req(0, need_pf_true);
1727
1728 Node *store_new_wmt = new StorePNode(need_pf_true,
1729 contended_phi_rawmem, eden_pf_adr,
1730 TypeRawPtr::BOTTOM, new_pf_wmt,
1731 MemNode::unordered);
1732 transform_later(store_new_wmt);
1733
1734 // adding prefetches
1735 pf_phi_abio->init_req( fall_in_path, i_o );
1736
1737 Node *prefetch_adr;
1738 Node *prefetch;
1739 uint step_size = AllocatePrefetchStepSize;
1740 uint distance = 0;
1741
1742 for ( intx i = 0; i < lines; i++ ) {
1743 prefetch_adr = new AddPNode( old_pf_wm, new_pf_wmt,
1744 _igvn.MakeConX(distance) );
1745 transform_later(prefetch_adr);
1746 prefetch = new PrefetchAllocationNode( i_o, prefetch_adr );
1747 transform_later(prefetch);
1748 distance += step_size;
1749 i_o = prefetch;
1750 }
1751 pf_phi_abio->set_req( pf_path, i_o );
1752
1753 pf_region->init_req( fall_in_path, need_pf_false );
1754 pf_region->init_req( pf_path, need_pf_true );
1755
1756 pf_phi_rawmem->init_req( fall_in_path, contended_phi_rawmem );
1757 pf_phi_rawmem->init_req( pf_path, store_new_wmt );
1758
1759 transform_later(pf_region);
1760 transform_later(pf_phi_rawmem);
1761 transform_later(pf_phi_abio);
1762
1763 needgc_false = pf_region;
1764 contended_phi_rawmem = pf_phi_rawmem;
1765 i_o = pf_phi_abio;
1766 } else if( UseTLAB && AllocatePrefetchStyle == 3 ) {
1767 // Insert a prefetch instruction for each allocation.
1768 // This code is used to generate 1 prefetch instruction per cache line.
1769
1770 // Generate several prefetch instructions.
1771 uint step_size = AllocatePrefetchStepSize;
1772 uint distance = AllocatePrefetchDistance;
1773
1774 // Next cache address.
1775 Node *cache_adr = new AddPNode(old_eden_top, old_eden_top,
1776 _igvn.MakeConX(step_size + distance));
1777 transform_later(cache_adr);
1778 cache_adr = new CastP2XNode(needgc_false, cache_adr);
1779 transform_later(cache_adr);
1780 // Address is aligned to execute prefetch to the beginning of cache line size
1781 // (it is important when BIS instruction is used on SPARC as prefetch).
1782 Node* mask = _igvn.MakeConX(~(intptr_t)(step_size-1));
1783 cache_adr = new AndXNode(cache_adr, mask);
1784 transform_later(cache_adr);
1785 cache_adr = new CastX2PNode(cache_adr);
1786 transform_later(cache_adr);
1787
1788 // Prefetch
1789 Node *prefetch = new PrefetchAllocationNode( contended_phi_rawmem, cache_adr );
1790 prefetch->set_req(0, needgc_false);
1791 transform_later(prefetch);
1792 contended_phi_rawmem = prefetch;
1793 Node *prefetch_adr;
1794 distance = step_size;
1795 for ( intx i = 1; i < lines; i++ ) {
1796 prefetch_adr = new AddPNode( cache_adr, cache_adr,
1797 _igvn.MakeConX(distance) );
1798 transform_later(prefetch_adr);
1799 prefetch = new PrefetchAllocationNode( contended_phi_rawmem, prefetch_adr );
1800 transform_later(prefetch);
1801 distance += step_size;
1802 contended_phi_rawmem = prefetch;
1803 }
1804 } else if( AllocatePrefetchStyle > 0 ) {
1805 // Insert a prefetch for each allocation only on the fast-path
1806 Node *prefetch_adr;
1807 Node *prefetch;
1808 // Generate several prefetch instructions.
1809 uint step_size = AllocatePrefetchStepSize;
1810 uint distance = AllocatePrefetchDistance;
1811 for ( intx i = 0; i < lines; i++ ) {
1812 prefetch_adr = new AddPNode( old_eden_top, new_eden_top,
1813 _igvn.MakeConX(distance) );
1814 transform_later(prefetch_adr);
1815 prefetch = new PrefetchAllocationNode( i_o, prefetch_adr );
1816 // Do not let it float too high, since if eden_top == eden_end,
1817 // both might be null.
1818 if( i == 0 ) { // Set control for first prefetch, next follows it
1819 prefetch->init_req(0, needgc_false);
1820 }
1821 transform_later(prefetch);
1822 distance += step_size;
1823 i_o = prefetch;
1824 }
1825 }
1826 return i_o;
1827 }
1828
1829
1830 void PhaseMacroExpand::expand_allocate(AllocateNode *alloc) {
1831 expand_allocate_common(alloc, NULL,
1832 OptoRuntime::new_instance_Type(),
1833 OptoRuntime::new_instance_Java());
1834 }
1835
1836 void PhaseMacroExpand::expand_allocate_array(AllocateArrayNode *alloc) {
1837 Node* length = alloc->in(AllocateNode::ALength);
1838 InitializeNode* init = alloc->initialization();
1839 Node* klass_node = alloc->in(AllocateNode::KlassNode);
1840 ciKlass* k = _igvn.type(klass_node)->is_klassptr()->klass();
1841 address slow_call_address; // Address of slow call
1842 if (init != NULL && init->is_complete_with_arraycopy() &&
1843 k->is_type_array_klass()) {
1844 // Don't zero type array during slow allocation in VM since
1845 // it will be initialized later by arraycopy in compiled code.
1846 slow_call_address = OptoRuntime::new_array_nozero_Java();
1847 } else {
1848 slow_call_address = OptoRuntime::new_array_Java();
1849 }
1850 expand_allocate_common(alloc, length,
1851 OptoRuntime::new_array_Type(),
1852 slow_call_address);
1853 }
1854
1855 //-------------------mark_eliminated_box----------------------------------
1856 //
1857 // During EA obj may point to several objects but after few ideal graph
1858 // transformations (CCP) it may point to only one non escaping object
1859 // (but still using phi), corresponding locks and unlocks will be marked
1860 // for elimination. Later obj could be replaced with a new node (new phi)
1861 // and which does not have escape information. And later after some graph
1862 // reshape other locks and unlocks (which were not marked for elimination
1863 // before) are connected to this new obj (phi) but they still will not be
1864 // marked for elimination since new obj has no escape information.
1865 // Mark all associated (same box and obj) lock and unlock nodes for
1866 // elimination if some of them marked already.
1867 void PhaseMacroExpand::mark_eliminated_box(Node* oldbox, Node* obj) {
1868 if (oldbox->as_BoxLock()->is_eliminated())
1869 return; // This BoxLock node was processed already.
1870
1871 // New implementation (EliminateNestedLocks) has separate BoxLock
1872 // node for each locked region so mark all associated locks/unlocks as
1873 // eliminated even if different objects are referenced in one locked region
1874 // (for example, OSR compilation of nested loop inside locked scope).
1875 if (EliminateNestedLocks ||
1876 oldbox->as_BoxLock()->is_simple_lock_region(NULL, obj)) {
1877 // Box is used only in one lock region. Mark this box as eliminated.
1878 _igvn.hash_delete(oldbox);
1879 oldbox->as_BoxLock()->set_eliminated(); // This changes box's hash value
1880 _igvn.hash_insert(oldbox);
1881
1882 for (uint i = 0; i < oldbox->outcnt(); i++) {
1883 Node* u = oldbox->raw_out(i);
1884 if (u->is_AbstractLock() && !u->as_AbstractLock()->is_non_esc_obj()) {
1885 AbstractLockNode* alock = u->as_AbstractLock();
1886 // Check lock's box since box could be referenced by Lock's debug info.
1887 if (alock->box_node() == oldbox) {
1888 // Mark eliminated all related locks and unlocks.
1889 #ifdef ASSERT
1890 alock->log_lock_optimization(C, "eliminate_lock_set_non_esc4");
1891 #endif
1892 alock->set_non_esc_obj();
1893 }
1894 }
1895 }
1896 return;
1897 }
1898
1899 // Create new "eliminated" BoxLock node and use it in monitor debug info
1900 // instead of oldbox for the same object.
1901 BoxLockNode* newbox = oldbox->clone()->as_BoxLock();
1902
1903 // Note: BoxLock node is marked eliminated only here and it is used
1904 // to indicate that all associated lock and unlock nodes are marked
1905 // for elimination.
1906 newbox->set_eliminated();
1907 transform_later(newbox);
1908
1909 // Replace old box node with new box for all users of the same object.
1910 for (uint i = 0; i < oldbox->outcnt();) {
1911 bool next_edge = true;
1912
1913 Node* u = oldbox->raw_out(i);
1914 if (u->is_AbstractLock()) {
1915 AbstractLockNode* alock = u->as_AbstractLock();
1916 if (alock->box_node() == oldbox && alock->obj_node()->eqv_uncast(obj)) {
1917 // Replace Box and mark eliminated all related locks and unlocks.
1918 #ifdef ASSERT
1919 alock->log_lock_optimization(C, "eliminate_lock_set_non_esc5");
1920 #endif
1921 alock->set_non_esc_obj();
1922 _igvn.rehash_node_delayed(alock);
1923 alock->set_box_node(newbox);
1924 next_edge = false;
1925 }
1926 }
1927 if (u->is_FastLock() && u->as_FastLock()->obj_node()->eqv_uncast(obj)) {
1928 FastLockNode* flock = u->as_FastLock();
1929 assert(flock->box_node() == oldbox, "sanity");
1930 _igvn.rehash_node_delayed(flock);
1931 flock->set_box_node(newbox);
1932 next_edge = false;
1933 }
1934
1935 // Replace old box in monitor debug info.
1936 if (u->is_SafePoint() && u->as_SafePoint()->jvms()) {
1937 SafePointNode* sfn = u->as_SafePoint();
1938 JVMState* youngest_jvms = sfn->jvms();
1939 int max_depth = youngest_jvms->depth();
1940 for (int depth = 1; depth <= max_depth; depth++) {
1941 JVMState* jvms = youngest_jvms->of_depth(depth);
1942 int num_mon = jvms->nof_monitors();
1943 // Loop over monitors
1944 for (int idx = 0; idx < num_mon; idx++) {
1945 Node* obj_node = sfn->monitor_obj(jvms, idx);
1946 Node* box_node = sfn->monitor_box(jvms, idx);
1947 if (box_node == oldbox && obj_node->eqv_uncast(obj)) {
1948 int j = jvms->monitor_box_offset(idx);
1949 _igvn.replace_input_of(u, j, newbox);
1950 next_edge = false;
1951 }
1952 }
1953 }
1954 }
1955 if (next_edge) i++;
1956 }
1957 }
1958
1959 //-----------------------mark_eliminated_locking_nodes-----------------------
1960 void PhaseMacroExpand::mark_eliminated_locking_nodes(AbstractLockNode *alock) {
1961 if (EliminateNestedLocks) {
1962 if (alock->is_nested()) {
1963 assert(alock->box_node()->as_BoxLock()->is_eliminated(), "sanity");
1964 return;
1965 } else if (!alock->is_non_esc_obj()) { // Not eliminated or coarsened
1966 // Only Lock node has JVMState needed here.
1967 // Not that preceding claim is documented anywhere else.
1968 if (alock->jvms() != NULL) {
1969 if (alock->as_Lock()->is_nested_lock_region()) {
1970 // Mark eliminated related nested locks and unlocks.
1971 Node* obj = alock->obj_node();
1972 BoxLockNode* box_node = alock->box_node()->as_BoxLock();
1973 assert(!box_node->is_eliminated(), "should not be marked yet");
1974 // Note: BoxLock node is marked eliminated only here
1975 // and it is used to indicate that all associated lock
1976 // and unlock nodes are marked for elimination.
1977 box_node->set_eliminated(); // Box's hash is always NO_HASH here
1978 for (uint i = 0; i < box_node->outcnt(); i++) {
1979 Node* u = box_node->raw_out(i);
1980 if (u->is_AbstractLock()) {
1981 alock = u->as_AbstractLock();
1982 if (alock->box_node() == box_node) {
1983 // Verify that this Box is referenced only by related locks.
1984 assert(alock->obj_node()->eqv_uncast(obj), "");
1985 // Mark all related locks and unlocks.
1986 #ifdef ASSERT
1987 alock->log_lock_optimization(C, "eliminate_lock_set_nested");
1988 #endif
1989 alock->set_nested();
1990 }
1991 }
1992 }
1993 } else {
1994 #ifdef ASSERT
1995 alock->log_lock_optimization(C, "eliminate_lock_NOT_nested_lock_region");
1996 if (C->log() != NULL)
1997 alock->as_Lock()->is_nested_lock_region(C); // rerun for debugging output
1998 #endif
1999 }
2000 }
2001 return;
2002 }
2003 // Process locks for non escaping object
2004 assert(alock->is_non_esc_obj(), "");
2005 } // EliminateNestedLocks
2006
2007 if (alock->is_non_esc_obj()) { // Lock is used for non escaping object
2008 // Look for all locks of this object and mark them and
2009 // corresponding BoxLock nodes as eliminated.
2010 Node* obj = alock->obj_node();
2011 for (uint j = 0; j < obj->outcnt(); j++) {
2012 Node* o = obj->raw_out(j);
2013 if (o->is_AbstractLock() &&
2014 o->as_AbstractLock()->obj_node()->eqv_uncast(obj)) {
2015 alock = o->as_AbstractLock();
2016 Node* box = alock->box_node();
2017 // Replace old box node with new eliminated box for all users
2018 // of the same object and mark related locks as eliminated.
2019 mark_eliminated_box(box, obj);
2020 }
2021 }
2022 }
2023 }
2024
2025 // we have determined that this lock/unlock can be eliminated, we simply
2026 // eliminate the node without expanding it.
2027 //
2028 // Note: The membar's associated with the lock/unlock are currently not
2029 // eliminated. This should be investigated as a future enhancement.
2030 //
2031 bool PhaseMacroExpand::eliminate_locking_node(AbstractLockNode *alock) {
2032
2033 if (!alock->is_eliminated()) {
2034 return false;
2035 }
2036 #ifdef ASSERT
2037 if (!alock->is_coarsened()) {
2038 // Check that new "eliminated" BoxLock node is created.
2039 BoxLockNode* oldbox = alock->box_node()->as_BoxLock();
2040 assert(oldbox->is_eliminated(), "should be done already");
2041 }
2042 #endif
2043
2044 alock->log_lock_optimization(C, "eliminate_lock");
2045
2046 #ifndef PRODUCT
2047 if (PrintEliminateLocks) {
2048 if (alock->is_Lock()) {
2049 tty->print_cr("++++ Eliminated: %d Lock", alock->_idx);
2050 } else {
2051 tty->print_cr("++++ Eliminated: %d Unlock", alock->_idx);
2052 }
2053 }
2054 #endif
2055
2056 Node* mem = alock->in(TypeFunc::Memory);
2057 Node* ctrl = alock->in(TypeFunc::Control);
2058 guarantee(ctrl != NULL, "missing control projection, cannot replace_node() with NULL");
2059
2060 extract_call_projections(alock);
2061 // There are 2 projections from the lock. The lock node will
2062 // be deleted when its last use is subsumed below.
2063 assert(alock->outcnt() == 2 &&
2064 _fallthroughproj != NULL &&
2065 _memproj_fallthrough != NULL,
2066 "Unexpected projections from Lock/Unlock");
2067
2068 Node* fallthroughproj = _fallthroughproj;
2069 Node* memproj_fallthrough = _memproj_fallthrough;
2070
2071 // The memory projection from a lock/unlock is RawMem
2072 // The input to a Lock is merged memory, so extract its RawMem input
2073 // (unless the MergeMem has been optimized away.)
2074 if (alock->is_Lock()) {
2075 // Seach for MemBarAcquireLock node and delete it also.
2076 MemBarNode* membar = fallthroughproj->unique_ctrl_out()->as_MemBar();
2077 assert(membar != NULL && membar->Opcode() == Op_MemBarAcquireLock, "");
2078 Node* ctrlproj = membar->proj_out(TypeFunc::Control);
2079 Node* memproj = membar->proj_out(TypeFunc::Memory);
2080 _igvn.replace_node(ctrlproj, fallthroughproj);
2081 _igvn.replace_node(memproj, memproj_fallthrough);
2082
2083 // Delete FastLock node also if this Lock node is unique user
2084 // (a loop peeling may clone a Lock node).
2085 Node* flock = alock->as_Lock()->fastlock_node();
2086 if (flock->outcnt() == 1) {
2087 assert(flock->unique_out() == alock, "sanity");
2088 _igvn.replace_node(flock, top());
2089 }
2090 }
2091
2092 // Seach for MemBarReleaseLock node and delete it also.
2093 if (alock->is_Unlock() && ctrl->is_Proj() && ctrl->in(0)->is_MemBar()) {
2094 MemBarNode* membar = ctrl->in(0)->as_MemBar();
2095 assert(membar->Opcode() == Op_MemBarReleaseLock &&
2096 mem->is_Proj() && membar == mem->in(0), "");
2097 _igvn.replace_node(fallthroughproj, ctrl);
2098 _igvn.replace_node(memproj_fallthrough, mem);
2099 fallthroughproj = ctrl;
2100 memproj_fallthrough = mem;
2101 ctrl = membar->in(TypeFunc::Control);
2102 mem = membar->in(TypeFunc::Memory);
2103 }
2104
2105 _igvn.replace_node(fallthroughproj, ctrl);
2106 _igvn.replace_node(memproj_fallthrough, mem);
2107 return true;
2108 }
2109
2110
2111 //------------------------------expand_lock_node----------------------
2112 void PhaseMacroExpand::expand_lock_node(LockNode *lock) {
2113
2114 Node* ctrl = lock->in(TypeFunc::Control);
2115 Node* mem = lock->in(TypeFunc::Memory);
2116 Node* obj = lock->obj_node();
2117 Node* box = lock->box_node();
2118 Node* flock = lock->fastlock_node();
2119
2120 assert(!box->as_BoxLock()->is_eliminated(), "sanity");
2121
2122 // Make the merge point
2123 Node *region;
2124 Node *mem_phi;
2125 Node *slow_path;
2126
2127 if (UseOptoBiasInlining) {
2128 /*
2129 * See the full description in MacroAssembler::biased_locking_enter().
2130 *
2131 * if( (mark_word & biased_lock_mask) == biased_lock_pattern ) {
2132 * // The object is biased.
2133 * proto_node = klass->prototype_header;
2134 * o_node = thread | proto_node;
2135 * x_node = o_node ^ mark_word;
2136 * if( (x_node & ~age_mask) == 0 ) { // Biased to the current thread ?
2137 * // Done.
2138 * } else {
2139 * if( (x_node & biased_lock_mask) != 0 ) {
2140 * // The klass's prototype header is no longer biased.
2141 * cas(&mark_word, mark_word, proto_node)
2142 * goto cas_lock;
2143 * } else {
2144 * // The klass's prototype header is still biased.
2145 * if( (x_node & epoch_mask) != 0 ) { // Expired epoch?
2146 * old = mark_word;
2147 * new = o_node;
2148 * } else {
2149 * // Different thread or anonymous biased.
2150 * old = mark_word & (epoch_mask | age_mask | biased_lock_mask);
2151 * new = thread | old;
2152 * }
2153 * // Try to rebias.
2154 * if( cas(&mark_word, old, new) == 0 ) {
2155 * // Done.
2156 * } else {
2157 * goto slow_path; // Failed.
2158 * }
2159 * }
2160 * }
2161 * } else {
2162 * // The object is not biased.
2163 * cas_lock:
2164 * if( FastLock(obj) == 0 ) {
2165 * // Done.
2166 * } else {
2167 * slow_path:
2168 * OptoRuntime::complete_monitor_locking_Java(obj);
2169 * }
2170 * }
2171 */
2172
2173 region = new RegionNode(5);
2174 // create a Phi for the memory state
2175 mem_phi = new PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM);
2176
2177 Node* fast_lock_region = new RegionNode(3);
2178 Node* fast_lock_mem_phi = new PhiNode( fast_lock_region, Type::MEMORY, TypeRawPtr::BOTTOM);
2179
2180 // First, check mark word for the biased lock pattern.
2181 Node* mark_node = make_load(ctrl, mem, obj, oopDesc::mark_offset_in_bytes(), TypeX_X, TypeX_X->basic_type());
2182
2183 // Get fast path - mark word has the biased lock pattern.
2184 ctrl = opt_bits_test(ctrl, fast_lock_region, 1, mark_node,
2185 markOopDesc::biased_lock_mask_in_place,
2186 markOopDesc::biased_lock_pattern, true);
2187 // fast_lock_region->in(1) is set to slow path.
2188 fast_lock_mem_phi->init_req(1, mem);
2189
2190 // Now check that the lock is biased to the current thread and has
2191 // the same epoch and bias as Klass::_prototype_header.
2192
2193 // Special-case a fresh allocation to avoid building nodes:
2194 Node* klass_node = AllocateNode::Ideal_klass(obj, &_igvn);
2195 if (klass_node == NULL) {
2196 Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes());
2197 klass_node = transform_later(LoadKlassNode::make(_igvn, NULL, mem, k_adr, _igvn.type(k_adr)->is_ptr()));
2198 #ifdef _LP64
2199 if (UseCompressedClassPointers && klass_node->is_DecodeNKlass()) {
2200 assert(klass_node->in(1)->Opcode() == Op_LoadNKlass, "sanity");
2201 klass_node->in(1)->init_req(0, ctrl);
2202 } else
2203 #endif
2204 klass_node->init_req(0, ctrl);
2205 }
2206 Node *proto_node = make_load(ctrl, mem, klass_node, in_bytes(Klass::prototype_header_offset()), TypeX_X, TypeX_X->basic_type());
2207
2208 Node* thread = transform_later(new ThreadLocalNode());
2209 Node* cast_thread = transform_later(new CastP2XNode(ctrl, thread));
2210 Node* o_node = transform_later(new OrXNode(cast_thread, proto_node));
2211 Node* x_node = transform_later(new XorXNode(o_node, mark_node));
2212
2213 // Get slow path - mark word does NOT match the value.
2214 Node* not_biased_ctrl = opt_bits_test(ctrl, region, 3, x_node,
2215 (~markOopDesc::age_mask_in_place), 0);
2216 // region->in(3) is set to fast path - the object is biased to the current thread.
2217 mem_phi->init_req(3, mem);
2218
2219
2220 // Mark word does NOT match the value (thread | Klass::_prototype_header).
2221
2222
2223 // First, check biased pattern.
2224 // Get fast path - _prototype_header has the same biased lock pattern.
2225 ctrl = opt_bits_test(not_biased_ctrl, fast_lock_region, 2, x_node,
2226 markOopDesc::biased_lock_mask_in_place, 0, true);
2227
2228 not_biased_ctrl = fast_lock_region->in(2); // Slow path
2229 // fast_lock_region->in(2) - the prototype header is no longer biased
2230 // and we have to revoke the bias on this object.
2231 // We are going to try to reset the mark of this object to the prototype
2232 // value and fall through to the CAS-based locking scheme.
2233 Node* adr = basic_plus_adr(obj, oopDesc::mark_offset_in_bytes());
2234 Node* cas = new StoreXConditionalNode(not_biased_ctrl, mem, adr,
2235 proto_node, mark_node);
2236 transform_later(cas);
2237 Node* proj = transform_later(new SCMemProjNode(cas));
2238 fast_lock_mem_phi->init_req(2, proj);
2239
2240
2241 // Second, check epoch bits.
2242 Node* rebiased_region = new RegionNode(3);
2243 Node* old_phi = new PhiNode( rebiased_region, TypeX_X);
2244 Node* new_phi = new PhiNode( rebiased_region, TypeX_X);
2245
2246 // Get slow path - mark word does NOT match epoch bits.
2247 Node* epoch_ctrl = opt_bits_test(ctrl, rebiased_region, 1, x_node,
2248 markOopDesc::epoch_mask_in_place, 0);
2249 // The epoch of the current bias is not valid, attempt to rebias the object
2250 // toward the current thread.
2251 rebiased_region->init_req(2, epoch_ctrl);
2252 old_phi->init_req(2, mark_node);
2253 new_phi->init_req(2, o_node);
2254
2255 // rebiased_region->in(1) is set to fast path.
2256 // The epoch of the current bias is still valid but we know
2257 // nothing about the owner; it might be set or it might be clear.
2258 Node* cmask = MakeConX(markOopDesc::biased_lock_mask_in_place |
2259 markOopDesc::age_mask_in_place |
2260 markOopDesc::epoch_mask_in_place);
2261 Node* old = transform_later(new AndXNode(mark_node, cmask));
2262 cast_thread = transform_later(new CastP2XNode(ctrl, thread));
2263 Node* new_mark = transform_later(new OrXNode(cast_thread, old));
2264 old_phi->init_req(1, old);
2265 new_phi->init_req(1, new_mark);
2266
2267 transform_later(rebiased_region);
2268 transform_later(old_phi);
2269 transform_later(new_phi);
2270
2271 // Try to acquire the bias of the object using an atomic operation.
2272 // If this fails we will go in to the runtime to revoke the object's bias.
2273 cas = new StoreXConditionalNode(rebiased_region, mem, adr, new_phi, old_phi);
2274 transform_later(cas);
2275 proj = transform_later(new SCMemProjNode(cas));
2276
2277 // Get slow path - Failed to CAS.
2278 not_biased_ctrl = opt_bits_test(rebiased_region, region, 4, cas, 0, 0);
2279 mem_phi->init_req(4, proj);
2280 // region->in(4) is set to fast path - the object is rebiased to the current thread.
2281
2282 // Failed to CAS.
2283 slow_path = new RegionNode(3);
2284 Node *slow_mem = new PhiNode( slow_path, Type::MEMORY, TypeRawPtr::BOTTOM);
2285
2286 slow_path->init_req(1, not_biased_ctrl); // Capture slow-control
2287 slow_mem->init_req(1, proj);
2288
2289 // Call CAS-based locking scheme (FastLock node).
2290
2291 transform_later(fast_lock_region);
2292 transform_later(fast_lock_mem_phi);
2293
2294 // Get slow path - FastLock failed to lock the object.
2295 ctrl = opt_bits_test(fast_lock_region, region, 2, flock, 0, 0);
2296 mem_phi->init_req(2, fast_lock_mem_phi);
2297 // region->in(2) is set to fast path - the object is locked to the current thread.
2298
2299 slow_path->init_req(2, ctrl); // Capture slow-control
2300 slow_mem->init_req(2, fast_lock_mem_phi);
2301
2302 transform_later(slow_path);
2303 transform_later(slow_mem);
2304 // Reset lock's memory edge.
2305 lock->set_req(TypeFunc::Memory, slow_mem);
2306
2307 } else {
2308 region = new RegionNode(3);
2309 // create a Phi for the memory state
2310 mem_phi = new PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM);
2311
2312 // Optimize test; set region slot 2
2313 slow_path = opt_bits_test(ctrl, region, 2, flock, 0, 0);
2314 mem_phi->init_req(2, mem);
2315 }
2316
2317 // Make slow path call
2318 CallNode *call = make_slow_call((CallNode *) lock, OptoRuntime::complete_monitor_enter_Type(),
2319 OptoRuntime::complete_monitor_locking_Java(), NULL, slow_path,
2320 obj, box, NULL);
2321
2322 extract_call_projections(call);
2323
2324 // Slow path can only throw asynchronous exceptions, which are always
2325 // de-opted. So the compiler thinks the slow-call can never throw an
2326 // exception. If it DOES throw an exception we would need the debug
2327 // info removed first (since if it throws there is no monitor).
2328 assert ( _ioproj_fallthrough == NULL && _ioproj_catchall == NULL &&
2329 _memproj_catchall == NULL && _catchallcatchproj == NULL, "Unexpected projection from Lock");
2330
2331 // Capture slow path
2332 // disconnect fall-through projection from call and create a new one
2333 // hook up users of fall-through projection to region
2334 Node *slow_ctrl = _fallthroughproj->clone();
2335 transform_later(slow_ctrl);
2336 _igvn.hash_delete(_fallthroughproj);
2337 _fallthroughproj->disconnect_inputs(NULL, C);
2338 region->init_req(1, slow_ctrl);
2339 // region inputs are now complete
2340 transform_later(region);
2341 _igvn.replace_node(_fallthroughproj, region);
2342
2343 Node *memproj = transform_later(new ProjNode(call, TypeFunc::Memory));
2344 mem_phi->init_req(1, memproj );
2345 transform_later(mem_phi);
2346 _igvn.replace_node(_memproj_fallthrough, mem_phi);
2347 }
2348
2349 //------------------------------expand_unlock_node----------------------
2350 void PhaseMacroExpand::expand_unlock_node(UnlockNode *unlock) {
2351
2352 Node* ctrl = unlock->in(TypeFunc::Control);
2353 Node* mem = unlock->in(TypeFunc::Memory);
2354 Node* obj = unlock->obj_node();
2355 Node* box = unlock->box_node();
2356
2357 assert(!box->as_BoxLock()->is_eliminated(), "sanity");
2358
2359 // No need for a null check on unlock
2360
2361 // Make the merge point
2362 Node *region;
2363 Node *mem_phi;
2364
2365 if (UseOptoBiasInlining) {
2366 // Check for biased locking unlock case, which is a no-op.
2367 // See the full description in MacroAssembler::biased_locking_exit().
2368 region = new RegionNode(4);
2369 // create a Phi for the memory state
2370 mem_phi = new PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM);
2371 mem_phi->init_req(3, mem);
2372
2373 Node* mark_node = make_load(ctrl, mem, obj, oopDesc::mark_offset_in_bytes(), TypeX_X, TypeX_X->basic_type());
2374 ctrl = opt_bits_test(ctrl, region, 3, mark_node,
2375 markOopDesc::biased_lock_mask_in_place,
2376 markOopDesc::biased_lock_pattern);
2377 } else {
2378 region = new RegionNode(3);
2379 // create a Phi for the memory state
2380 mem_phi = new PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM);
2381 }
2382
2383 FastUnlockNode *funlock = new FastUnlockNode( ctrl, obj, box );
2384 funlock = transform_later( funlock )->as_FastUnlock();
2385 // Optimize test; set region slot 2
2386 Node *slow_path = opt_bits_test(ctrl, region, 2, funlock, 0, 0);
2387 Node *thread = transform_later(new ThreadLocalNode());
2388
2389 CallNode *call = make_slow_call((CallNode *) unlock, OptoRuntime::complete_monitor_exit_Type(),
2390 CAST_FROM_FN_PTR(address, SharedRuntime::complete_monitor_unlocking_C),
2391 "complete_monitor_unlocking_C", slow_path, obj, box, thread);
2392
2393 extract_call_projections(call);
2394
2395 assert ( _ioproj_fallthrough == NULL && _ioproj_catchall == NULL &&
2396 _memproj_catchall == NULL && _catchallcatchproj == NULL, "Unexpected projection from Lock");
2397
2398 // No exceptions for unlocking
2399 // Capture slow path
2400 // disconnect fall-through projection from call and create a new one
2401 // hook up users of fall-through projection to region
2402 Node *slow_ctrl = _fallthroughproj->clone();
2403 transform_later(slow_ctrl);
2404 _igvn.hash_delete(_fallthroughproj);
2405 _fallthroughproj->disconnect_inputs(NULL, C);
2406 region->init_req(1, slow_ctrl);
2407 // region inputs are now complete
2408 transform_later(region);
2409 _igvn.replace_node(_fallthroughproj, region);
2410
2411 Node *memproj = transform_later(new ProjNode(call, TypeFunc::Memory) );
2412 mem_phi->init_req(1, memproj );
2413 mem_phi->init_req(2, mem);
2414 transform_later(mem_phi);
2415 _igvn.replace_node(_memproj_fallthrough, mem_phi);
2416 }
2417
2418 //---------------------------eliminate_macro_nodes----------------------
2419 // Eliminate scalar replaced allocations and associated locks.
2420 void PhaseMacroExpand::eliminate_macro_nodes() {
2421 if (C->macro_count() == 0)
2422 return;
2423
2424 // First, attempt to eliminate locks
2425 int cnt = C->macro_count();
2426 for (int i=0; i < cnt; i++) {
2427 Node *n = C->macro_node(i);
2428 if (n->is_AbstractLock()) { // Lock and Unlock nodes
2429 // Before elimination mark all associated (same box and obj)
2430 // lock and unlock nodes.
2431 mark_eliminated_locking_nodes(n->as_AbstractLock());
2432 }
2433 }
2434 bool progress = true;
2435 while (progress) {
2436 progress = false;
2437 for (int i = C->macro_count(); i > 0; i--) {
2438 Node * n = C->macro_node(i-1);
2439 bool success = false;
2440 debug_only(int old_macro_count = C->macro_count(););
2441 if (n->is_AbstractLock()) {
2442 success = eliminate_locking_node(n->as_AbstractLock());
2443 }
2444 assert(success == (C->macro_count() < old_macro_count), "elimination reduces macro count");
2445 progress = progress || success;
2446 }
2447 }
2448 // Next, attempt to eliminate allocations
2449 _has_locks = false;
2450 progress = true;
2451 while (progress) {
2452 progress = false;
2453 for (int i = C->macro_count(); i > 0; i--) {
2454 Node * n = C->macro_node(i-1);
2455 bool success = false;
2456 debug_only(int old_macro_count = C->macro_count(););
2457 switch (n->class_id()) {
2458 case Node::Class_Allocate:
2459 case Node::Class_AllocateArray:
2460 success = eliminate_allocate_node(n->as_Allocate());
2461 break;
2462 case Node::Class_CallStaticJava:
2463 success = eliminate_boxing_node(n->as_CallStaticJava());
2464 break;
2465 case Node::Class_Lock:
2466 case Node::Class_Unlock:
2467 assert(!n->as_AbstractLock()->is_eliminated(), "sanity");
2468 _has_locks = true;
2469 break;
2470 case Node::Class_ArrayCopy:
2471 break;
2472 case Node::Class_OuterStripMinedLoop:
2473 break;
2474 default:
2475 assert(n->Opcode() == Op_LoopLimit ||
2476 n->Opcode() == Op_Opaque1 ||
2477 n->Opcode() == Op_Opaque2 ||
2478 n->Opcode() == Op_Opaque3 ||
2479 BarrierSet::barrier_set()->barrier_set_c2()->is_gc_barrier_node(n),
2480 "unknown node type in macro list");
2481 }
2482 assert(success == (C->macro_count() < old_macro_count), "elimination reduces macro count");
2483 progress = progress || success;
2484 }
2485 }
2486 }
2487
2488 //------------------------------expand_macro_nodes----------------------
2489 // Returns true if a failure occurred.
2490 bool PhaseMacroExpand::expand_macro_nodes() {
2491 // Last attempt to eliminate macro nodes.
2492 eliminate_macro_nodes();
2493
2494 // Make sure expansion will not cause node limit to be exceeded.
2495 // Worst case is a macro node gets expanded into about 200 nodes.
2496 // Allow 50% more for optimization.
2497 if (C->check_node_count(C->macro_count() * 300, "out of nodes before macro expansion" ) )
2498 return true;
2499
2500 // Eliminate Opaque and LoopLimit nodes. Do it after all loop optimizations.
2501 bool progress = true;
2502 while (progress) {
2503 progress = false;
2504 for (int i = C->macro_count(); i > 0; i--) {
2505 Node * n = C->macro_node(i-1);
2506 bool success = false;
2507 debug_only(int old_macro_count = C->macro_count(););
2508 if (n->Opcode() == Op_LoopLimit) {
2509 // Remove it from macro list and put on IGVN worklist to optimize.
2510 C->remove_macro_node(n);
2511 _igvn._worklist.push(n);
2512 success = true;
2513 } else if (n->Opcode() == Op_CallStaticJava) {
2514 // Remove it from macro list and put on IGVN worklist to optimize.
2515 C->remove_macro_node(n);
2516 _igvn._worklist.push(n);
2517 success = true;
2518 } else if (n->Opcode() == Op_Opaque1 || n->Opcode() == Op_Opaque2) {
2519 _igvn.replace_node(n, n->in(1));
2520 success = true;
2521 #if INCLUDE_RTM_OPT
2522 } else if ((n->Opcode() == Op_Opaque3) && ((Opaque3Node*)n)->rtm_opt()) {
2523 assert(C->profile_rtm(), "should be used only in rtm deoptimization code");
2524 assert((n->outcnt() == 1) && n->unique_out()->is_Cmp(), "");
2525 Node* cmp = n->unique_out();
2526 #ifdef ASSERT
2527 // Validate graph.
2528 assert((cmp->outcnt() == 1) && cmp->unique_out()->is_Bool(), "");
2529 BoolNode* bol = cmp->unique_out()->as_Bool();
2530 assert((bol->outcnt() == 1) && bol->unique_out()->is_If() &&
2531 (bol->_test._test == BoolTest::ne), "");
2532 IfNode* ifn = bol->unique_out()->as_If();
2533 assert((ifn->outcnt() == 2) &&
2534 ifn->proj_out(1)->is_uncommon_trap_proj(Deoptimization::Reason_rtm_state_change) != NULL, "");
2535 #endif
2536 Node* repl = n->in(1);
2537 if (!_has_locks) {
2538 // Remove RTM state check if there are no locks in the code.
2539 // Replace input to compare the same value.
2540 repl = (cmp->in(1) == n) ? cmp->in(2) : cmp->in(1);
2541 }
2542 _igvn.replace_node(n, repl);
2543 success = true;
2544 #endif
2545 } else if (n->Opcode() == Op_OuterStripMinedLoop) {
2546 n->as_OuterStripMinedLoop()->adjust_strip_mined_loop(&_igvn);
2547 C->remove_macro_node(n);
2548 success = true;
2549 }
2550 assert(success == (C->macro_count() < old_macro_count), "elimination reduces macro count");
2551 progress = progress || success;
2552 }
2553 }
2554
2555 // expand arraycopy "macro" nodes first
2556 // For ReduceBulkZeroing, we must first process all arraycopy nodes
2557 // before the allocate nodes are expanded.
2558 int macro_idx = C->macro_count() - 1;
2559 while (macro_idx >= 0) {
2560 Node * n = C->macro_node(macro_idx);
2561 assert(n->is_macro(), "only macro nodes expected here");
2562 if (_igvn.type(n) == Type::TOP || (n->in(0) != NULL && n->in(0)->is_top())) {
2563 // node is unreachable, so don't try to expand it
2564 C->remove_macro_node(n);
2565 } else if (n->is_ArrayCopy()){
2566 int macro_count = C->macro_count();
2567 expand_arraycopy_node(n->as_ArrayCopy());
2568 assert(C->macro_count() < macro_count, "must have deleted a node from macro list");
2569 }
2570 if (C->failing()) return true;
2571 macro_idx --;
2572 }
2573
2574 // expand "macro" nodes
2575 // nodes are removed from the macro list as they are processed
2576 while (C->macro_count() > 0) {
2577 int macro_count = C->macro_count();
2578 Node * n = C->macro_node(macro_count-1);
2579 assert(n->is_macro(), "only macro nodes expected here");
2580 if (_igvn.type(n) == Type::TOP || (n->in(0) != NULL && n->in(0)->is_top())) {
2581 // node is unreachable, so don't try to expand it
2582 C->remove_macro_node(n);
2583 continue;
2584 }
2585 switch (n->class_id()) {
2586 case Node::Class_Allocate:
2587 expand_allocate(n->as_Allocate());
2588 break;
2589 case Node::Class_AllocateArray:
2590 expand_allocate_array(n->as_AllocateArray());
2591 break;
2592 case Node::Class_Lock:
2593 expand_lock_node(n->as_Lock());
2594 break;
2595 case Node::Class_Unlock:
2596 expand_unlock_node(n->as_Unlock());
2597 break;
2598 default:
2599 assert(false, "unknown node type in macro list");
2600 }
2601 assert(C->macro_count() < macro_count, "must have deleted a node from macro list");
2602 if (C->failing()) return true;
2603 }
2604
2605 _igvn.set_delay_transform(false);
2606 _igvn.optimize();
2607 if (C->failing()) return true;
2608 return false;
2609 }