1 /*
2 * Copyright (c) 2005, 2011, 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 "libadt/vectset.hpp"
28 #include "opto/addnode.hpp"
29 #include "opto/callnode.hpp"
30 #include "opto/cfgnode.hpp"
31 #include "opto/compile.hpp"
32 #include "opto/connode.hpp"
33 #include "opto/locknode.hpp"
34 #include "opto/loopnode.hpp"
35 #include "opto/macro.hpp"
36 #include "opto/memnode.hpp"
37 #include "opto/node.hpp"
38 #include "opto/phaseX.hpp"
39 #include "opto/rootnode.hpp"
40 #include "opto/runtime.hpp"
41 #include "opto/subnode.hpp"
42 #include "opto/type.hpp"
43 #include "runtime/sharedRuntime.hpp"
44
45
46 //
47 // Replace any references to "oldref" in inputs to "use" with "newref".
48 // Returns the number of replacements made.
49 //
50 int PhaseMacroExpand::replace_input(Node *use, Node *oldref, Node *newref) {
51 int nreplacements = 0;
52 uint req = use->req();
53 for (uint j = 0; j < use->len(); j++) {
54 Node *uin = use->in(j);
55 if (uin == oldref) {
56 if (j < req)
57 use->set_req(j, newref);
58 else
59 use->set_prec(j, newref);
60 nreplacements++;
61 } else if (j >= req && uin == NULL) {
62 break;
63 }
64 }
65 return nreplacements;
66 }
67
68 void PhaseMacroExpand::copy_call_debug_info(CallNode *oldcall, CallNode * newcall) {
69 // Copy debug information and adjust JVMState information
70 uint old_dbg_start = oldcall->tf()->domain()->cnt();
71 uint new_dbg_start = newcall->tf()->domain()->cnt();
72 int jvms_adj = new_dbg_start - old_dbg_start;
73 assert (new_dbg_start == newcall->req(), "argument count mismatch");
74
75 Dict* sosn_map = new Dict(cmpkey,hashkey);
76 for (uint i = old_dbg_start; i < oldcall->req(); i++) {
77 Node* old_in = oldcall->in(i);
78 // Clone old SafePointScalarObjectNodes, adjusting their field contents.
79 if (old_in != NULL && old_in->is_SafePointScalarObject()) {
80 SafePointScalarObjectNode* old_sosn = old_in->as_SafePointScalarObject();
81 uint old_unique = C->unique();
82 Node* new_in = old_sosn->clone(jvms_adj, sosn_map);
83 if (old_unique != C->unique()) {
84 new_in->set_req(0, C->root()); // reset control edge
85 new_in = transform_later(new_in); // Register new node.
86 }
87 old_in = new_in;
88 }
89 newcall->add_req(old_in);
90 }
91
92 newcall->set_jvms(oldcall->jvms());
93 for (JVMState *jvms = newcall->jvms(); jvms != NULL; jvms = jvms->caller()) {
94 jvms->set_map(newcall);
95 jvms->set_locoff(jvms->locoff()+jvms_adj);
96 jvms->set_stkoff(jvms->stkoff()+jvms_adj);
97 jvms->set_monoff(jvms->monoff()+jvms_adj);
98 jvms->set_scloff(jvms->scloff()+jvms_adj);
99 jvms->set_endoff(jvms->endoff()+jvms_adj);
100 }
101 }
102
103 Node* PhaseMacroExpand::opt_bits_test(Node* ctrl, Node* region, int edge, Node* word, int mask, int bits, bool return_fast_path) {
104 Node* cmp;
105 if (mask != 0) {
106 Node* and_node = transform_later(new (C, 3) AndXNode(word, MakeConX(mask)));
107 cmp = transform_later(new (C, 3) CmpXNode(and_node, MakeConX(bits)));
108 } else {
109 cmp = word;
110 }
111 Node* bol = transform_later(new (C, 2) BoolNode(cmp, BoolTest::ne));
112 IfNode* iff = new (C, 2) IfNode( ctrl, bol, PROB_MIN, COUNT_UNKNOWN );
113 transform_later(iff);
114
115 // Fast path taken.
116 Node *fast_taken = transform_later( new (C, 1) IfFalseNode(iff) );
117
118 // Fast path not-taken, i.e. slow path
119 Node *slow_taken = transform_later( new (C, 1) IfTrueNode(iff) );
120
121 if (return_fast_path) {
122 region->init_req(edge, slow_taken); // Capture slow-control
123 return fast_taken;
124 } else {
125 region->init_req(edge, fast_taken); // Capture fast-control
126 return slow_taken;
127 }
128 }
129
130 //--------------------copy_predefined_input_for_runtime_call--------------------
131 void PhaseMacroExpand::copy_predefined_input_for_runtime_call(Node * ctrl, CallNode* oldcall, CallNode* call) {
132 // Set fixed predefined input arguments
133 call->init_req( TypeFunc::Control, ctrl );
134 call->init_req( TypeFunc::I_O , oldcall->in( TypeFunc::I_O) );
135 call->init_req( TypeFunc::Memory , oldcall->in( TypeFunc::Memory ) ); // ?????
136 call->init_req( TypeFunc::ReturnAdr, oldcall->in( TypeFunc::ReturnAdr ) );
137 call->init_req( TypeFunc::FramePtr, oldcall->in( TypeFunc::FramePtr ) );
138 }
139
140 //------------------------------make_slow_call---------------------------------
141 CallNode* PhaseMacroExpand::make_slow_call(CallNode *oldcall, const TypeFunc* slow_call_type, address slow_call, const char* leaf_name, Node* slow_path, Node* parm0, Node* parm1) {
142
143 // Slow-path call
144 int size = slow_call_type->domain()->cnt();
145 CallNode *call = leaf_name
146 ? (CallNode*)new (C, size) CallLeafNode ( slow_call_type, slow_call, leaf_name, TypeRawPtr::BOTTOM )
147 : (CallNode*)new (C, size) CallStaticJavaNode( slow_call_type, slow_call, OptoRuntime::stub_name(slow_call), oldcall->jvms()->bci(), TypeRawPtr::BOTTOM );
148
149 // Slow path call has no side-effects, uses few values
150 copy_predefined_input_for_runtime_call(slow_path, oldcall, call );
151 if (parm0 != NULL) call->init_req(TypeFunc::Parms+0, parm0);
152 if (parm1 != NULL) call->init_req(TypeFunc::Parms+1, parm1);
153 copy_call_debug_info(oldcall, call);
154 call->set_cnt(PROB_UNLIKELY_MAG(4)); // Same effect as RC_UNCOMMON.
155 _igvn.replace_node(oldcall, call);
156 transform_later(call);
157
158 return call;
159 }
160
161 void PhaseMacroExpand::extract_call_projections(CallNode *call) {
162 _fallthroughproj = NULL;
163 _fallthroughcatchproj = NULL;
164 _ioproj_fallthrough = NULL;
165 _ioproj_catchall = NULL;
166 _catchallcatchproj = NULL;
167 _memproj_fallthrough = NULL;
168 _memproj_catchall = NULL;
169 _resproj = NULL;
170 for (DUIterator_Fast imax, i = call->fast_outs(imax); i < imax; i++) {
171 ProjNode *pn = call->fast_out(i)->as_Proj();
172 switch (pn->_con) {
173 case TypeFunc::Control:
174 {
175 // For Control (fallthrough) and I_O (catch_all_index) we have CatchProj -> Catch -> Proj
176 _fallthroughproj = pn;
177 DUIterator_Fast jmax, j = pn->fast_outs(jmax);
178 const Node *cn = pn->fast_out(j);
179 if (cn->is_Catch()) {
180 ProjNode *cpn = NULL;
181 for (DUIterator_Fast kmax, k = cn->fast_outs(kmax); k < kmax; k++) {
182 cpn = cn->fast_out(k)->as_Proj();
183 assert(cpn->is_CatchProj(), "must be a CatchProjNode");
184 if (cpn->_con == CatchProjNode::fall_through_index)
185 _fallthroughcatchproj = cpn;
186 else {
187 assert(cpn->_con == CatchProjNode::catch_all_index, "must be correct index.");
188 _catchallcatchproj = cpn;
189 }
190 }
191 }
192 break;
193 }
194 case TypeFunc::I_O:
195 if (pn->_is_io_use)
196 _ioproj_catchall = pn;
197 else
198 _ioproj_fallthrough = pn;
199 break;
200 case TypeFunc::Memory:
201 if (pn->_is_io_use)
202 _memproj_catchall = pn;
203 else
204 _memproj_fallthrough = pn;
205 break;
206 case TypeFunc::Parms:
207 _resproj = pn;
208 break;
209 default:
210 assert(false, "unexpected projection from allocation node.");
211 }
212 }
213
214 }
215
216 // Eliminate a card mark sequence. p2x is a ConvP2XNode
217 void PhaseMacroExpand::eliminate_card_mark(Node* p2x) {
218 assert(p2x->Opcode() == Op_CastP2X, "ConvP2XNode required");
219 if (!UseG1GC) {
220 // vanilla/CMS post barrier
221 Node *shift = p2x->unique_out();
222 Node *addp = shift->unique_out();
223 for (DUIterator_Last jmin, j = addp->last_outs(jmin); j >= jmin; --j) {
224 Node *mem = addp->last_out(j);
225 if (UseCondCardMark && mem->is_Load()) {
226 assert(mem->Opcode() == Op_LoadB, "unexpected code shape");
227 // The load is checking if the card has been written so
228 // replace it with zero to fold the test.
229 _igvn.replace_node(mem, intcon(0));
230 continue;
231 }
232 assert(mem->is_Store(), "store required");
233 _igvn.replace_node(mem, mem->in(MemNode::Memory));
234 }
235 } else {
236 // G1 pre/post barriers
237 assert(p2x->outcnt() == 2, "expects 2 users: Xor and URShift nodes");
238 // It could be only one user, URShift node, in Object.clone() instrinsic
239 // but the new allocation is passed to arraycopy stub and it could not
240 // be scalar replaced. So we don't check the case.
241
242 // Remove G1 post barrier.
243
244 // Search for CastP2X->Xor->URShift->Cmp path which
245 // checks if the store done to a different from the value's region.
246 // And replace Cmp with #0 (false) to collapse G1 post barrier.
247 Node* xorx = NULL;
248 for (DUIterator_Fast imax, i = p2x->fast_outs(imax); i < imax; i++) {
249 Node* u = p2x->fast_out(i);
250 if (u->Opcode() == Op_XorX) {
251 xorx = u;
252 break;
253 }
254 }
255 assert(xorx != NULL, "missing G1 post barrier");
256 Node* shift = xorx->unique_out();
257 Node* cmpx = shift->unique_out();
258 assert(cmpx->is_Cmp() && cmpx->unique_out()->is_Bool() &&
259 cmpx->unique_out()->as_Bool()->_test._test == BoolTest::ne,
260 "missing region check in G1 post barrier");
261 _igvn.replace_node(cmpx, makecon(TypeInt::CC_EQ));
262
263 // Remove G1 pre barrier.
264
265 // Search "if (marking != 0)" check and set it to "false".
266 Node* this_region = p2x->in(0);
267 assert(this_region != NULL, "");
268 // There is no G1 pre barrier if previous stored value is NULL
269 // (for example, after initialization).
270 if (this_region->is_Region() && this_region->req() == 3) {
271 int ind = 1;
272 if (!this_region->in(ind)->is_IfFalse()) {
273 ind = 2;
274 }
275 if (this_region->in(ind)->is_IfFalse()) {
276 Node* bol = this_region->in(ind)->in(0)->in(1);
277 assert(bol->is_Bool(), "");
278 cmpx = bol->in(1);
279 if (bol->as_Bool()->_test._test == BoolTest::ne &&
280 cmpx->is_Cmp() && cmpx->in(2) == intcon(0) &&
281 cmpx->in(1)->is_Load()) {
282 Node* adr = cmpx->in(1)->as_Load()->in(MemNode::Address);
283 const int marking_offset = in_bytes(JavaThread::satb_mark_queue_offset() +
284 PtrQueue::byte_offset_of_active());
285 if (adr->is_AddP() && adr->in(AddPNode::Base) == top() &&
286 adr->in(AddPNode::Address)->Opcode() == Op_ThreadLocal &&
287 adr->in(AddPNode::Offset) == MakeConX(marking_offset)) {
288 _igvn.replace_node(cmpx, makecon(TypeInt::CC_EQ));
289 }
290 }
291 }
292 }
293 // Now CastP2X can be removed since it is used only on dead path
294 // which currently still alive until igvn optimize it.
295 assert(p2x->unique_out()->Opcode() == Op_URShiftX, "");
296 _igvn.replace_node(p2x, top());
297 }
298 }
299
300 // Search for a memory operation for the specified memory slice.
301 static Node *scan_mem_chain(Node *mem, int alias_idx, int offset, Node *start_mem, Node *alloc, PhaseGVN *phase) {
302 Node *orig_mem = mem;
303 Node *alloc_mem = alloc->in(TypeFunc::Memory);
304 const TypeOopPtr *tinst = phase->C->get_adr_type(alias_idx)->isa_oopptr();
305 while (true) {
306 if (mem == alloc_mem || mem == start_mem ) {
307 return mem; // hit one of our sentinels
308 } else if (mem->is_MergeMem()) {
309 mem = mem->as_MergeMem()->memory_at(alias_idx);
310 } else if (mem->is_Proj() && mem->as_Proj()->_con == TypeFunc::Memory) {
311 Node *in = mem->in(0);
312 // we can safely skip over safepoints, calls, locks and membars because we
313 // already know that the object is safe to eliminate.
314 if (in->is_Initialize() && in->as_Initialize()->allocation() == alloc) {
315 return in;
316 } else if (in->is_Call()) {
317 CallNode *call = in->as_Call();
318 if (!call->may_modify(tinst, phase)) {
319 mem = call->in(TypeFunc::Memory);
320 }
321 mem = in->in(TypeFunc::Memory);
322 } else if (in->is_MemBar()) {
323 mem = in->in(TypeFunc::Memory);
324 } else {
325 assert(false, "unexpected projection");
326 }
327 } else if (mem->is_Store()) {
328 const TypePtr* atype = mem->as_Store()->adr_type();
329 int adr_idx = Compile::current()->get_alias_index(atype);
330 if (adr_idx == alias_idx) {
331 assert(atype->isa_oopptr(), "address type must be oopptr");
332 int adr_offset = atype->offset();
333 uint adr_iid = atype->is_oopptr()->instance_id();
334 // Array elements references have the same alias_idx
335 // but different offset and different instance_id.
336 if (adr_offset == offset && adr_iid == alloc->_idx)
337 return mem;
338 } else {
339 assert(adr_idx == Compile::AliasIdxRaw, "address must match or be raw");
340 }
341 mem = mem->in(MemNode::Memory);
342 } else if (mem->is_ClearArray()) {
343 if (!ClearArrayNode::step_through(&mem, alloc->_idx, phase)) {
344 // Can not bypass initialization of the instance
345 // we are looking.
346 debug_only(intptr_t offset;)
347 assert(alloc == AllocateNode::Ideal_allocation(mem->in(3), phase, offset), "sanity");
348 InitializeNode* init = alloc->as_Allocate()->initialization();
349 // We are looking for stored value, return Initialize node
350 // or memory edge from Allocate node.
351 if (init != NULL)
352 return init;
353 else
354 return alloc->in(TypeFunc::Memory); // It will produce zero value (see callers).
355 }
356 // Otherwise skip it (the call updated 'mem' value).
357 } else if (mem->Opcode() == Op_SCMemProj) {
358 assert(mem->in(0)->is_LoadStore(), "sanity");
359 const TypePtr* atype = mem->in(0)->in(MemNode::Address)->bottom_type()->is_ptr();
360 int adr_idx = Compile::current()->get_alias_index(atype);
361 if (adr_idx == alias_idx) {
362 assert(false, "Object is not scalar replaceable if a LoadStore node access its field");
363 return NULL;
364 }
365 mem = mem->in(0)->in(MemNode::Memory);
366 } else {
367 return mem;
368 }
369 assert(mem != orig_mem, "dead memory loop");
370 }
371 }
372
373 //
374 // Given a Memory Phi, compute a value Phi containing the values from stores
375 // on the input paths.
376 // Note: this function is recursive, its depth is limied by the "level" argument
377 // Returns the computed Phi, or NULL if it cannot compute it.
378 Node *PhaseMacroExpand::value_from_mem_phi(Node *mem, BasicType ft, const Type *phi_type, const TypeOopPtr *adr_t, Node *alloc, Node_Stack *value_phis, int level) {
379 assert(mem->is_Phi(), "sanity");
380 int alias_idx = C->get_alias_index(adr_t);
381 int offset = adr_t->offset();
382 int instance_id = adr_t->instance_id();
383
384 // Check if an appropriate value phi already exists.
385 Node* region = mem->in(0);
386 for (DUIterator_Fast kmax, k = region->fast_outs(kmax); k < kmax; k++) {
387 Node* phi = region->fast_out(k);
388 if (phi->is_Phi() && phi != mem &&
389 phi->as_Phi()->is_same_inst_field(phi_type, instance_id, alias_idx, offset)) {
390 return phi;
391 }
392 }
393 // Check if an appropriate new value phi already exists.
394 Node* new_phi = value_phis->find(mem->_idx);
395 if (new_phi != NULL)
396 return new_phi;
397
398 if (level <= 0) {
399 return NULL; // Give up: phi tree too deep
400 }
401 Node *start_mem = C->start()->proj_out(TypeFunc::Memory);
402 Node *alloc_mem = alloc->in(TypeFunc::Memory);
403
404 uint length = mem->req();
405 GrowableArray <Node *> values(length, length, NULL);
406
407 // create a new Phi for the value
408 PhiNode *phi = new (C, length) PhiNode(mem->in(0), phi_type, NULL, instance_id, alias_idx, offset);
409 transform_later(phi);
410 value_phis->push(phi, mem->_idx);
411
412 for (uint j = 1; j < length; j++) {
413 Node *in = mem->in(j);
414 if (in == NULL || in->is_top()) {
415 values.at_put(j, in);
416 } else {
417 Node *val = scan_mem_chain(in, alias_idx, offset, start_mem, alloc, &_igvn);
418 if (val == start_mem || val == alloc_mem) {
419 // hit a sentinel, return appropriate 0 value
420 values.at_put(j, _igvn.zerocon(ft));
421 continue;
422 }
423 if (val->is_Initialize()) {
424 val = val->as_Initialize()->find_captured_store(offset, type2aelembytes(ft), &_igvn);
425 }
426 if (val == NULL) {
427 return NULL; // can't find a value on this path
428 }
429 if (val == mem) {
430 values.at_put(j, mem);
431 } else if (val->is_Store()) {
432 values.at_put(j, val->in(MemNode::ValueIn));
433 } else if(val->is_Proj() && val->in(0) == alloc) {
434 values.at_put(j, _igvn.zerocon(ft));
435 } else if (val->is_Phi()) {
436 val = value_from_mem_phi(val, ft, phi_type, adr_t, alloc, value_phis, level-1);
437 if (val == NULL) {
438 return NULL;
439 }
440 values.at_put(j, val);
441 } else if (val->Opcode() == Op_SCMemProj) {
442 assert(val->in(0)->is_LoadStore(), "sanity");
443 assert(false, "Object is not scalar replaceable if a LoadStore node access its field");
444 return NULL;
445 } else {
446 #ifdef ASSERT
447 val->dump();
448 assert(false, "unknown node on this path");
449 #endif
450 return NULL; // unknown node on this path
451 }
452 }
453 }
454 // Set Phi's inputs
455 for (uint j = 1; j < length; j++) {
456 if (values.at(j) == mem) {
457 phi->init_req(j, phi);
458 } else {
459 phi->init_req(j, values.at(j));
460 }
461 }
462 return phi;
463 }
464
465 // Search the last value stored into the object's field.
466 Node *PhaseMacroExpand::value_from_mem(Node *sfpt_mem, BasicType ft, const Type *ftype, const TypeOopPtr *adr_t, Node *alloc) {
467 assert(adr_t->is_known_instance_field(), "instance required");
468 int instance_id = adr_t->instance_id();
469 assert((uint)instance_id == alloc->_idx, "wrong allocation");
470
471 int alias_idx = C->get_alias_index(adr_t);
472 int offset = adr_t->offset();
473 Node *start_mem = C->start()->proj_out(TypeFunc::Memory);
474 Node *alloc_ctrl = alloc->in(TypeFunc::Control);
475 Node *alloc_mem = alloc->in(TypeFunc::Memory);
476 Arena *a = Thread::current()->resource_area();
477 VectorSet visited(a);
478
479
480 bool done = sfpt_mem == alloc_mem;
481 Node *mem = sfpt_mem;
482 while (!done) {
483 if (visited.test_set(mem->_idx)) {
484 return NULL; // found a loop, give up
485 }
486 mem = scan_mem_chain(mem, alias_idx, offset, start_mem, alloc, &_igvn);
487 if (mem == start_mem || mem == alloc_mem) {
488 done = true; // hit a sentinel, return appropriate 0 value
489 } else if (mem->is_Initialize()) {
490 mem = mem->as_Initialize()->find_captured_store(offset, type2aelembytes(ft), &_igvn);
491 if (mem == NULL) {
492 done = true; // Something go wrong.
493 } else if (mem->is_Store()) {
494 const TypePtr* atype = mem->as_Store()->adr_type();
495 assert(C->get_alias_index(atype) == Compile::AliasIdxRaw, "store is correct memory slice");
496 done = true;
497 }
498 } else if (mem->is_Store()) {
499 const TypeOopPtr* atype = mem->as_Store()->adr_type()->isa_oopptr();
500 assert(atype != NULL, "address type must be oopptr");
501 assert(C->get_alias_index(atype) == alias_idx &&
502 atype->is_known_instance_field() && atype->offset() == offset &&
503 atype->instance_id() == instance_id, "store is correct memory slice");
504 done = true;
505 } else if (mem->is_Phi()) {
506 // try to find a phi's unique input
507 Node *unique_input = NULL;
508 Node *top = C->top();
509 for (uint i = 1; i < mem->req(); i++) {
510 Node *n = scan_mem_chain(mem->in(i), alias_idx, offset, start_mem, alloc, &_igvn);
511 if (n == NULL || n == top || n == mem) {
512 continue;
513 } else if (unique_input == NULL) {
514 unique_input = n;
515 } else if (unique_input != n) {
516 unique_input = top;
517 break;
518 }
519 }
520 if (unique_input != NULL && unique_input != top) {
521 mem = unique_input;
522 } else {
523 done = true;
524 }
525 } else {
526 assert(false, "unexpected node");
527 }
528 }
529 if (mem != NULL) {
530 if (mem == start_mem || mem == alloc_mem) {
531 // hit a sentinel, return appropriate 0 value
532 return _igvn.zerocon(ft);
533 } else if (mem->is_Store()) {
534 return mem->in(MemNode::ValueIn);
535 } else if (mem->is_Phi()) {
536 // attempt to produce a Phi reflecting the values on the input paths of the Phi
537 Node_Stack value_phis(a, 8);
538 Node * phi = value_from_mem_phi(mem, ft, ftype, adr_t, alloc, &value_phis, ValueSearchLimit);
539 if (phi != NULL) {
540 return phi;
541 } else {
542 // Kill all new Phis
543 while(value_phis.is_nonempty()) {
544 Node* n = value_phis.node();
545 _igvn.replace_node(n, C->top());
546 value_phis.pop();
547 }
548 }
549 }
550 }
551 // Something go wrong.
552 return NULL;
553 }
554
555 // Check the possibility of scalar replacement.
556 bool PhaseMacroExpand::can_eliminate_allocation(AllocateNode *alloc, GrowableArray <SafePointNode *>& safepoints) {
557 // Scan the uses of the allocation to check for anything that would
558 // prevent us from eliminating it.
559 NOT_PRODUCT( const char* fail_eliminate = NULL; )
560 DEBUG_ONLY( Node* disq_node = NULL; )
561 bool can_eliminate = true;
562
563 Node* res = alloc->result_cast();
564 const TypeOopPtr* res_type = NULL;
565 if (res == NULL) {
566 // All users were eliminated.
567 } else if (!res->is_CheckCastPP()) {
568 NOT_PRODUCT(fail_eliminate = "Allocation does not have unique CheckCastPP";)
569 can_eliminate = false;
570 } else {
571 res_type = _igvn.type(res)->isa_oopptr();
572 if (res_type == NULL) {
573 NOT_PRODUCT(fail_eliminate = "Neither instance or array allocation";)
574 can_eliminate = false;
575 } else if (res_type->isa_aryptr()) {
576 int length = alloc->in(AllocateNode::ALength)->find_int_con(-1);
577 if (length < 0) {
578 NOT_PRODUCT(fail_eliminate = "Array's size is not constant";)
579 can_eliminate = false;
580 }
581 }
582 }
583
584 if (can_eliminate && res != NULL) {
585 for (DUIterator_Fast jmax, j = res->fast_outs(jmax);
586 j < jmax && can_eliminate; j++) {
587 Node* use = res->fast_out(j);
588
589 if (use->is_AddP()) {
590 const TypePtr* addp_type = _igvn.type(use)->is_ptr();
591 int offset = addp_type->offset();
592
593 if (offset == Type::OffsetTop || offset == Type::OffsetBot) {
594 NOT_PRODUCT(fail_eliminate = "Undefined field referrence";)
595 can_eliminate = false;
596 break;
597 }
598 for (DUIterator_Fast kmax, k = use->fast_outs(kmax);
599 k < kmax && can_eliminate; k++) {
600 Node* n = use->fast_out(k);
601 if (!n->is_Store() && n->Opcode() != Op_CastP2X) {
602 DEBUG_ONLY(disq_node = n;)
603 if (n->is_Load() || n->is_LoadStore()) {
604 NOT_PRODUCT(fail_eliminate = "Field load";)
605 } else {
606 NOT_PRODUCT(fail_eliminate = "Not store field referrence";)
607 }
608 can_eliminate = false;
609 }
610 }
611 } else if (use->is_SafePoint()) {
612 SafePointNode* sfpt = use->as_SafePoint();
613 if (sfpt->is_Call() && sfpt->as_Call()->has_non_debug_use(res)) {
614 // Object is passed as argument.
615 DEBUG_ONLY(disq_node = use;)
616 NOT_PRODUCT(fail_eliminate = "Object is passed as argument";)
617 can_eliminate = false;
618 }
619 Node* sfptMem = sfpt->memory();
620 if (sfptMem == NULL || sfptMem->is_top()) {
621 DEBUG_ONLY(disq_node = use;)
622 NOT_PRODUCT(fail_eliminate = "NULL or TOP memory";)
623 can_eliminate = false;
624 } else {
625 safepoints.append_if_missing(sfpt);
626 }
627 } else if (use->Opcode() != Op_CastP2X) { // CastP2X is used by card mark
628 if (use->is_Phi()) {
629 if (use->outcnt() == 1 && use->unique_out()->Opcode() == Op_Return) {
630 NOT_PRODUCT(fail_eliminate = "Object is return value";)
631 } else {
632 NOT_PRODUCT(fail_eliminate = "Object is referenced by Phi";)
633 }
634 DEBUG_ONLY(disq_node = use;)
635 } else {
636 if (use->Opcode() == Op_Return) {
637 NOT_PRODUCT(fail_eliminate = "Object is return value";)
638 }else {
639 NOT_PRODUCT(fail_eliminate = "Object is referenced by node";)
640 }
641 DEBUG_ONLY(disq_node = use;)
642 }
643 can_eliminate = false;
644 }
645 }
646 }
647
648 #ifndef PRODUCT
649 if (PrintEliminateAllocations) {
650 if (can_eliminate) {
651 tty->print("Scalar ");
652 if (res == NULL)
653 alloc->dump();
654 else
655 res->dump();
656 } else {
657 tty->print("NotScalar (%s)", fail_eliminate);
658 if (res == NULL)
659 alloc->dump();
660 else
661 res->dump();
662 #ifdef ASSERT
663 if (disq_node != NULL) {
664 tty->print(" >>>> ");
665 disq_node->dump();
666 }
667 #endif /*ASSERT*/
668 }
669 }
670 #endif
671 return can_eliminate;
672 }
673
674 // Do scalar replacement.
675 bool PhaseMacroExpand::scalar_replacement(AllocateNode *alloc, GrowableArray <SafePointNode *>& safepoints) {
676 GrowableArray <SafePointNode *> safepoints_done;
677
678 ciKlass* klass = NULL;
679 ciInstanceKlass* iklass = NULL;
680 int nfields = 0;
681 int array_base;
682 int element_size;
683 BasicType basic_elem_type;
684 ciType* elem_type;
685
686 Node* res = alloc->result_cast();
687 const TypeOopPtr* res_type = NULL;
688 if (res != NULL) { // Could be NULL when there are no users
689 res_type = _igvn.type(res)->isa_oopptr();
690 }
691
692 if (res != NULL) {
693 klass = res_type->klass();
694 if (res_type->isa_instptr()) {
695 // find the fields of the class which will be needed for safepoint debug information
696 assert(klass->is_instance_klass(), "must be an instance klass.");
697 iklass = klass->as_instance_klass();
698 nfields = iklass->nof_nonstatic_fields();
699 } else {
700 // find the array's elements which will be needed for safepoint debug information
701 nfields = alloc->in(AllocateNode::ALength)->find_int_con(-1);
702 assert(klass->is_array_klass() && nfields >= 0, "must be an array klass.");
703 elem_type = klass->as_array_klass()->element_type();
704 basic_elem_type = elem_type->basic_type();
705 array_base = arrayOopDesc::base_offset_in_bytes(basic_elem_type);
706 element_size = type2aelembytes(basic_elem_type);
707 }
708 }
709 //
710 // Process the safepoint uses
711 //
712 while (safepoints.length() > 0) {
713 SafePointNode* sfpt = safepoints.pop();
714 Node* mem = sfpt->memory();
715 uint first_ind = sfpt->req();
716 SafePointScalarObjectNode* sobj = new (C, 1) SafePointScalarObjectNode(res_type,
717 #ifdef ASSERT
718 alloc,
719 #endif
720 first_ind, nfields);
721 sobj->init_req(0, C->root());
722 transform_later(sobj);
723
724 // Scan object's fields adding an input to the safepoint for each field.
725 for (int j = 0; j < nfields; j++) {
726 intptr_t offset;
727 ciField* field = NULL;
728 if (iklass != NULL) {
729 field = iklass->nonstatic_field_at(j);
730 offset = field->offset();
731 elem_type = field->type();
732 basic_elem_type = field->layout_type();
733 } else {
734 offset = array_base + j * (intptr_t)element_size;
735 }
736
737 const Type *field_type;
738 // The next code is taken from Parse::do_get_xxx().
739 if (basic_elem_type == T_OBJECT || basic_elem_type == T_ARRAY) {
740 if (!elem_type->is_loaded()) {
741 field_type = TypeInstPtr::BOTTOM;
742 } else if (field != NULL && field->is_constant() && field->is_static()) {
743 // This can happen if the constant oop is non-perm.
744 ciObject* con = field->constant_value().as_object();
745 // Do not "join" in the previous type; it doesn't add value,
746 // and may yield a vacuous result if the field is of interface type.
747 field_type = TypeOopPtr::make_from_constant(con)->isa_oopptr();
748 assert(field_type != NULL, "field singleton type must be consistent");
749 } else {
750 field_type = TypeOopPtr::make_from_klass(elem_type->as_klass());
751 }
752 if (UseCompressedOops) {
753 field_type = field_type->make_narrowoop();
754 basic_elem_type = T_NARROWOOP;
755 }
756 } else {
757 field_type = Type::get_const_basic_type(basic_elem_type);
758 }
759
760 const TypeOopPtr *field_addr_type = res_type->add_offset(offset)->isa_oopptr();
761
762 Node *field_val = value_from_mem(mem, basic_elem_type, field_type, field_addr_type, alloc);
763 if (field_val == NULL) {
764 // We weren't able to find a value for this field,
765 // give up on eliminating this allocation.
766
767 // Remove any extra entries we added to the safepoint.
768 uint last = sfpt->req() - 1;
769 for (int k = 0; k < j; k++) {
770 sfpt->del_req(last--);
771 }
772 // rollback processed safepoints
773 while (safepoints_done.length() > 0) {
774 SafePointNode* sfpt_done = safepoints_done.pop();
775 // remove any extra entries we added to the safepoint
776 last = sfpt_done->req() - 1;
777 for (int k = 0; k < nfields; k++) {
778 sfpt_done->del_req(last--);
779 }
780 JVMState *jvms = sfpt_done->jvms();
781 jvms->set_endoff(sfpt_done->req());
782 // Now make a pass over the debug information replacing any references
783 // to SafePointScalarObjectNode with the allocated object.
784 int start = jvms->debug_start();
785 int end = jvms->debug_end();
786 for (int i = start; i < end; i++) {
787 if (sfpt_done->in(i)->is_SafePointScalarObject()) {
788 SafePointScalarObjectNode* scobj = sfpt_done->in(i)->as_SafePointScalarObject();
789 if (scobj->first_index() == sfpt_done->req() &&
790 scobj->n_fields() == (uint)nfields) {
791 assert(scobj->alloc() == alloc, "sanity");
792 sfpt_done->set_req(i, res);
793 }
794 }
795 }
796 }
797 #ifndef PRODUCT
798 if (PrintEliminateAllocations) {
799 if (field != NULL) {
800 tty->print("=== At SafePoint node %d can't find value of Field: ",
801 sfpt->_idx);
802 field->print();
803 int field_idx = C->get_alias_index(field_addr_type);
804 tty->print(" (alias_idx=%d)", field_idx);
805 } else { // Array's element
806 tty->print("=== At SafePoint node %d can't find value of array element [%d]",
807 sfpt->_idx, j);
808 }
809 tty->print(", which prevents elimination of: ");
810 if (res == NULL)
811 alloc->dump();
812 else
813 res->dump();
814 }
815 #endif
816 return false;
817 }
818 if (UseCompressedOops && field_type->isa_narrowoop()) {
819 // Enable "DecodeN(EncodeP(Allocate)) --> Allocate" transformation
820 // to be able scalar replace the allocation.
821 if (field_val->is_EncodeP()) {
822 field_val = field_val->in(1);
823 } else {
824 field_val = transform_later(new (C, 2) DecodeNNode(field_val, field_val->bottom_type()->make_ptr()));
825 }
826 }
827 sfpt->add_req(field_val);
828 }
829 JVMState *jvms = sfpt->jvms();
830 jvms->set_endoff(sfpt->req());
831 // Now make a pass over the debug information replacing any references
832 // to the allocated object with "sobj"
833 int start = jvms->debug_start();
834 int end = jvms->debug_end();
835 for (int i = start; i < end; i++) {
836 if (sfpt->in(i) == res) {
837 sfpt->set_req(i, sobj);
838 }
839 }
840 safepoints_done.append_if_missing(sfpt); // keep it for rollback
841 }
842 return true;
843 }
844
845 // Process users of eliminated allocation.
846 void PhaseMacroExpand::process_users_of_allocation(AllocateNode *alloc) {
847 Node* res = alloc->result_cast();
848 if (res != NULL) {
849 for (DUIterator_Last jmin, j = res->last_outs(jmin); j >= jmin; ) {
850 Node *use = res->last_out(j);
851 uint oc1 = res->outcnt();
852
853 if (use->is_AddP()) {
854 for (DUIterator_Last kmin, k = use->last_outs(kmin); k >= kmin; ) {
855 Node *n = use->last_out(k);
856 uint oc2 = use->outcnt();
857 if (n->is_Store()) {
858 #ifdef ASSERT
859 // Verify that there is no dependent MemBarVolatile nodes,
860 // they should be removed during IGVN, see MemBarNode::Ideal().
861 for (DUIterator_Fast pmax, p = n->fast_outs(pmax);
862 p < pmax; p++) {
863 Node* mb = n->fast_out(p);
864 assert(mb->is_Initialize() || !mb->is_MemBar() ||
865 mb->req() <= MemBarNode::Precedent ||
866 mb->in(MemBarNode::Precedent) != n,
867 "MemBarVolatile should be eliminated for non-escaping object");
868 }
869 #endif
870 _igvn.replace_node(n, n->in(MemNode::Memory));
871 } else {
872 eliminate_card_mark(n);
873 }
874 k -= (oc2 - use->outcnt());
875 }
876 } else {
877 eliminate_card_mark(use);
878 }
879 j -= (oc1 - res->outcnt());
880 }
881 assert(res->outcnt() == 0, "all uses of allocated objects must be deleted");
882 _igvn.remove_dead_node(res);
883 }
884
885 //
886 // Process other users of allocation's projections
887 //
888 if (_resproj != NULL && _resproj->outcnt() != 0) {
889 for (DUIterator_Last jmin, j = _resproj->last_outs(jmin); j >= jmin; ) {
890 Node *use = _resproj->last_out(j);
891 uint oc1 = _resproj->outcnt();
892 if (use->is_Initialize()) {
893 // Eliminate Initialize node.
894 InitializeNode *init = use->as_Initialize();
895 assert(init->outcnt() <= 2, "only a control and memory projection expected");
896 Node *ctrl_proj = init->proj_out(TypeFunc::Control);
897 if (ctrl_proj != NULL) {
898 assert(init->in(TypeFunc::Control) == _fallthroughcatchproj, "allocation control projection");
899 _igvn.replace_node(ctrl_proj, _fallthroughcatchproj);
900 }
901 Node *mem_proj = init->proj_out(TypeFunc::Memory);
902 if (mem_proj != NULL) {
903 Node *mem = init->in(TypeFunc::Memory);
904 #ifdef ASSERT
905 if (mem->is_MergeMem()) {
906 assert(mem->in(TypeFunc::Memory) == _memproj_fallthrough, "allocation memory projection");
907 } else {
908 assert(mem == _memproj_fallthrough, "allocation memory projection");
909 }
910 #endif
911 _igvn.replace_node(mem_proj, mem);
912 }
913 } else if (use->is_AddP()) {
914 // raw memory addresses used only by the initialization
915 _igvn.replace_node(use, C->top());
916 } else {
917 assert(false, "only Initialize or AddP expected");
918 }
919 j -= (oc1 - _resproj->outcnt());
920 }
921 }
922 if (_fallthroughcatchproj != NULL) {
923 _igvn.replace_node(_fallthroughcatchproj, alloc->in(TypeFunc::Control));
924 }
925 if (_memproj_fallthrough != NULL) {
926 _igvn.replace_node(_memproj_fallthrough, alloc->in(TypeFunc::Memory));
927 }
928 if (_memproj_catchall != NULL) {
929 _igvn.replace_node(_memproj_catchall, C->top());
930 }
931 if (_ioproj_fallthrough != NULL) {
932 _igvn.replace_node(_ioproj_fallthrough, alloc->in(TypeFunc::I_O));
933 }
934 if (_ioproj_catchall != NULL) {
935 _igvn.replace_node(_ioproj_catchall, C->top());
936 }
937 if (_catchallcatchproj != NULL) {
938 _igvn.replace_node(_catchallcatchproj, C->top());
939 }
940 }
941
942 bool PhaseMacroExpand::eliminate_allocate_node(AllocateNode *alloc) {
943
944 if (!EliminateAllocations || !alloc->_is_scalar_replaceable) {
945 return false;
946 }
947
948 extract_call_projections(alloc);
949
950 GrowableArray <SafePointNode *> safepoints;
951 if (!can_eliminate_allocation(alloc, safepoints)) {
952 return false;
953 }
954
955 if (!scalar_replacement(alloc, safepoints)) {
956 return false;
957 }
958
959 CompileLog* log = C->log();
960 if (log != NULL) {
961 Node* klass = alloc->in(AllocateNode::KlassNode);
962 const TypeKlassPtr* tklass = _igvn.type(klass)->is_klassptr();
963 log->head("eliminate_allocation type='%d'",
964 log->identify(tklass->klass()));
965 JVMState* p = alloc->jvms();
966 while (p != NULL) {
967 log->elem("jvms bci='%d' method='%d'", p->bci(), log->identify(p->method()));
968 p = p->caller();
969 }
970 log->tail("eliminate_allocation");
971 }
972
973 process_users_of_allocation(alloc);
974
975 #ifndef PRODUCT
976 if (PrintEliminateAllocations) {
977 if (alloc->is_AllocateArray())
978 tty->print_cr("++++ Eliminated: %d AllocateArray", alloc->_idx);
979 else
980 tty->print_cr("++++ Eliminated: %d Allocate", alloc->_idx);
981 }
982 #endif
983
984 return true;
985 }
986
987
988 //---------------------------set_eden_pointers-------------------------
989 void PhaseMacroExpand::set_eden_pointers(Node* &eden_top_adr, Node* &eden_end_adr) {
990 if (UseTLAB) { // Private allocation: load from TLS
991 Node* thread = transform_later(new (C, 1) ThreadLocalNode());
992 int tlab_top_offset = in_bytes(JavaThread::tlab_top_offset());
993 int tlab_end_offset = in_bytes(JavaThread::tlab_end_offset());
994 eden_top_adr = basic_plus_adr(top()/*not oop*/, thread, tlab_top_offset);
995 eden_end_adr = basic_plus_adr(top()/*not oop*/, thread, tlab_end_offset);
996 } else { // Shared allocation: load from globals
997 CollectedHeap* ch = Universe::heap();
998 address top_adr = (address)ch->top_addr();
999 address end_adr = (address)ch->end_addr();
1000 eden_top_adr = makecon(TypeRawPtr::make(top_adr));
1001 eden_end_adr = basic_plus_adr(eden_top_adr, end_adr - top_adr);
1002 }
1003 }
1004
1005
1006 Node* PhaseMacroExpand::make_load(Node* ctl, Node* mem, Node* base, int offset, const Type* value_type, BasicType bt) {
1007 Node* adr = basic_plus_adr(base, offset);
1008 const TypePtr* adr_type = adr->bottom_type()->is_ptr();
1009 Node* value = LoadNode::make(_igvn, ctl, mem, adr, adr_type, value_type, bt);
1010 transform_later(value);
1011 return value;
1012 }
1013
1014
1015 Node* PhaseMacroExpand::make_store(Node* ctl, Node* mem, Node* base, int offset, Node* value, BasicType bt) {
1016 Node* adr = basic_plus_adr(base, offset);
1017 mem = StoreNode::make(_igvn, ctl, mem, adr, NULL, value, bt);
1018 transform_later(mem);
1019 return mem;
1020 }
1021
1022 //=============================================================================
1023 //
1024 // A L L O C A T I O N
1025 //
1026 // Allocation attempts to be fast in the case of frequent small objects.
1027 // It breaks down like this:
1028 //
1029 // 1) Size in doublewords is computed. This is a constant for objects and
1030 // variable for most arrays. Doubleword units are used to avoid size
1031 // overflow of huge doubleword arrays. We need doublewords in the end for
1032 // rounding.
1033 //
1034 // 2) Size is checked for being 'too large'. Too-large allocations will go
1035 // the slow path into the VM. The slow path can throw any required
1036 // exceptions, and does all the special checks for very large arrays. The
1037 // size test can constant-fold away for objects. For objects with
1038 // finalizers it constant-folds the otherway: you always go slow with
1039 // finalizers.
1040 //
1041 // 3) If NOT using TLABs, this is the contended loop-back point.
1042 // Load-Locked the heap top. If using TLABs normal-load the heap top.
1043 //
1044 // 4) Check that heap top + size*8 < max. If we fail go the slow ` route.
1045 // NOTE: "top+size*8" cannot wrap the 4Gig line! Here's why: for largish
1046 // "size*8" we always enter the VM, where "largish" is a constant picked small
1047 // enough that there's always space between the eden max and 4Gig (old space is
1048 // there so it's quite large) and large enough that the cost of entering the VM
1049 // is dwarfed by the cost to initialize the space.
1050 //
1051 // 5) If NOT using TLABs, Store-Conditional the adjusted heap top back
1052 // down. If contended, repeat at step 3. If using TLABs normal-store
1053 // adjusted heap top back down; there is no contention.
1054 //
1055 // 6) If !ZeroTLAB then Bulk-clear the object/array. Fill in klass & mark
1056 // fields.
1057 //
1058 // 7) Merge with the slow-path; cast the raw memory pointer to the correct
1059 // oop flavor.
1060 //
1061 //=============================================================================
1062 // FastAllocateSizeLimit value is in DOUBLEWORDS.
1063 // Allocations bigger than this always go the slow route.
1064 // This value must be small enough that allocation attempts that need to
1065 // trigger exceptions go the slow route. Also, it must be small enough so
1066 // that heap_top + size_in_bytes does not wrap around the 4Gig limit.
1067 //=============================================================================j//
1068 // %%% Here is an old comment from parseHelper.cpp; is it outdated?
1069 // The allocator will coalesce int->oop copies away. See comment in
1070 // coalesce.cpp about how this works. It depends critically on the exact
1071 // code shape produced here, so if you are changing this code shape
1072 // make sure the GC info for the heap-top is correct in and around the
1073 // slow-path call.
1074 //
1075
1076 void PhaseMacroExpand::expand_allocate_common(
1077 AllocateNode* alloc, // allocation node to be expanded
1078 Node* length, // array length for an array allocation
1079 const TypeFunc* slow_call_type, // Type of slow call
1080 address slow_call_address // Address of slow call
1081 )
1082 {
1083
1084 Node* ctrl = alloc->in(TypeFunc::Control);
1085 Node* mem = alloc->in(TypeFunc::Memory);
1086 Node* i_o = alloc->in(TypeFunc::I_O);
1087 Node* size_in_bytes = alloc->in(AllocateNode::AllocSize);
1088 Node* klass_node = alloc->in(AllocateNode::KlassNode);
1089 Node* initial_slow_test = alloc->in(AllocateNode::InitialTest);
1090
1091 Node* storestore = alloc->storestore();
1092 if (storestore != NULL) {
1093 // Break this link that is no longer useful and confuses register allocation
1094 storestore->set_req(MemBarNode::Precedent, top());
1095 }
1096
1097 assert(ctrl != NULL, "must have control");
1098 // We need a Region and corresponding Phi's to merge the slow-path and fast-path results.
1099 // they will not be used if "always_slow" is set
1100 enum { slow_result_path = 1, fast_result_path = 2 };
1101 Node *result_region;
1102 Node *result_phi_rawmem;
1103 Node *result_phi_rawoop;
1104 Node *result_phi_i_o;
1105
1106 // The initial slow comparison is a size check, the comparison
1107 // we want to do is a BoolTest::gt
1108 bool always_slow = false;
1109 int tv = _igvn.find_int_con(initial_slow_test, -1);
1110 if (tv >= 0) {
1111 always_slow = (tv == 1);
1112 initial_slow_test = NULL;
1113 } else {
1114 initial_slow_test = BoolNode::make_predicate(initial_slow_test, &_igvn);
1115 }
1116
1117 if (C->env()->dtrace_alloc_probes() ||
1118 !UseTLAB && (!Universe::heap()->supports_inline_contig_alloc() ||
1119 (UseConcMarkSweepGC && CMSIncrementalMode))) {
1120 // Force slow-path allocation
1121 always_slow = true;
1122 initial_slow_test = NULL;
1123 }
1124
1125
1126 enum { too_big_or_final_path = 1, need_gc_path = 2 };
1127 Node *slow_region = NULL;
1128 Node *toobig_false = ctrl;
1129
1130 assert (initial_slow_test == NULL || !always_slow, "arguments must be consistent");
1131 // generate the initial test if necessary
1132 if (initial_slow_test != NULL ) {
1133 slow_region = new (C, 3) RegionNode(3);
1134
1135 // Now make the initial failure test. Usually a too-big test but
1136 // might be a TRUE for finalizers or a fancy class check for
1137 // newInstance0.
1138 IfNode *toobig_iff = new (C, 2) IfNode(ctrl, initial_slow_test, PROB_MIN, COUNT_UNKNOWN);
1139 transform_later(toobig_iff);
1140 // Plug the failing-too-big test into the slow-path region
1141 Node *toobig_true = new (C, 1) IfTrueNode( toobig_iff );
1142 transform_later(toobig_true);
1143 slow_region ->init_req( too_big_or_final_path, toobig_true );
1144 toobig_false = new (C, 1) IfFalseNode( toobig_iff );
1145 transform_later(toobig_false);
1146 } else { // No initial test, just fall into next case
1147 toobig_false = ctrl;
1148 debug_only(slow_region = NodeSentinel);
1149 }
1150
1151 Node *slow_mem = mem; // save the current memory state for slow path
1152 // generate the fast allocation code unless we know that the initial test will always go slow
1153 if (!always_slow) {
1154 // Fast path modifies only raw memory.
1155 if (mem->is_MergeMem()) {
1156 mem = mem->as_MergeMem()->memory_at(Compile::AliasIdxRaw);
1157 }
1158
1159 Node* eden_top_adr;
1160 Node* eden_end_adr;
1161
1162 set_eden_pointers(eden_top_adr, eden_end_adr);
1163
1164 // Load Eden::end. Loop invariant and hoisted.
1165 //
1166 // Note: We set the control input on "eden_end" and "old_eden_top" when using
1167 // a TLAB to work around a bug where these values were being moved across
1168 // a safepoint. These are not oops, so they cannot be include in the oop
1169 // map, but they can be changed by a GC. The proper way to fix this would
1170 // be to set the raw memory state when generating a SafepointNode. However
1171 // this will require extensive changes to the loop optimization in order to
1172 // prevent a degradation of the optimization.
1173 // See comment in memnode.hpp, around line 227 in class LoadPNode.
1174 Node *eden_end = make_load(ctrl, mem, eden_end_adr, 0, TypeRawPtr::BOTTOM, T_ADDRESS);
1175
1176 // allocate the Region and Phi nodes for the result
1177 result_region = new (C, 3) RegionNode(3);
1178 result_phi_rawmem = new (C, 3) PhiNode(result_region, Type::MEMORY, TypeRawPtr::BOTTOM);
1179 result_phi_rawoop = new (C, 3) PhiNode(result_region, TypeRawPtr::BOTTOM);
1180 result_phi_i_o = new (C, 3) PhiNode(result_region, Type::ABIO); // I/O is used for Prefetch
1181
1182 // We need a Region for the loop-back contended case.
1183 enum { fall_in_path = 1, contended_loopback_path = 2 };
1184 Node *contended_region;
1185 Node *contended_phi_rawmem;
1186 if (UseTLAB) {
1187 contended_region = toobig_false;
1188 contended_phi_rawmem = mem;
1189 } else {
1190 contended_region = new (C, 3) RegionNode(3);
1191 contended_phi_rawmem = new (C, 3) PhiNode(contended_region, Type::MEMORY, TypeRawPtr::BOTTOM);
1192 // Now handle the passing-too-big test. We fall into the contended
1193 // loop-back merge point.
1194 contended_region ->init_req(fall_in_path, toobig_false);
1195 contended_phi_rawmem->init_req(fall_in_path, mem);
1196 transform_later(contended_region);
1197 transform_later(contended_phi_rawmem);
1198 }
1199
1200 // Load(-locked) the heap top.
1201 // See note above concerning the control input when using a TLAB
1202 Node *old_eden_top = UseTLAB
1203 ? new (C, 3) LoadPNode (ctrl, contended_phi_rawmem, eden_top_adr, TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM)
1204 : new (C, 3) LoadPLockedNode(contended_region, contended_phi_rawmem, eden_top_adr);
1205
1206 transform_later(old_eden_top);
1207 // Add to heap top to get a new heap top
1208 Node *new_eden_top = new (C, 4) AddPNode(top(), old_eden_top, size_in_bytes);
1209 transform_later(new_eden_top);
1210 // Check for needing a GC; compare against heap end
1211 Node *needgc_cmp = new (C, 3) CmpPNode(new_eden_top, eden_end);
1212 transform_later(needgc_cmp);
1213 Node *needgc_bol = new (C, 2) BoolNode(needgc_cmp, BoolTest::ge);
1214 transform_later(needgc_bol);
1215 IfNode *needgc_iff = new (C, 2) IfNode(contended_region, needgc_bol, PROB_UNLIKELY_MAG(4), COUNT_UNKNOWN);
1216 transform_later(needgc_iff);
1217
1218 // Plug the failing-heap-space-need-gc test into the slow-path region
1219 Node *needgc_true = new (C, 1) IfTrueNode(needgc_iff);
1220 transform_later(needgc_true);
1221 if (initial_slow_test) {
1222 slow_region->init_req(need_gc_path, needgc_true);
1223 // This completes all paths into the slow merge point
1224 transform_later(slow_region);
1225 } else { // No initial slow path needed!
1226 // Just fall from the need-GC path straight into the VM call.
1227 slow_region = needgc_true;
1228 }
1229 // No need for a GC. Setup for the Store-Conditional
1230 Node *needgc_false = new (C, 1) IfFalseNode(needgc_iff);
1231 transform_later(needgc_false);
1232
1233 // Grab regular I/O before optional prefetch may change it.
1234 // Slow-path does no I/O so just set it to the original I/O.
1235 result_phi_i_o->init_req(slow_result_path, i_o);
1236
1237 i_o = prefetch_allocation(i_o, needgc_false, contended_phi_rawmem,
1238 old_eden_top, new_eden_top, length);
1239
1240 // Name successful fast-path variables
1241 Node* fast_oop = old_eden_top;
1242 Node* fast_oop_ctrl;
1243 Node* fast_oop_rawmem;
1244
1245 // Store (-conditional) the modified eden top back down.
1246 // StorePConditional produces flags for a test PLUS a modified raw
1247 // memory state.
1248 if (UseTLAB) {
1249 Node* store_eden_top =
1250 new (C, 4) StorePNode(needgc_false, contended_phi_rawmem, eden_top_adr,
1251 TypeRawPtr::BOTTOM, new_eden_top);
1252 transform_later(store_eden_top);
1253 fast_oop_ctrl = needgc_false; // No contention, so this is the fast path
1254 fast_oop_rawmem = store_eden_top;
1255 } else {
1256 Node* store_eden_top =
1257 new (C, 5) StorePConditionalNode(needgc_false, contended_phi_rawmem, eden_top_adr,
1258 new_eden_top, fast_oop/*old_eden_top*/);
1259 transform_later(store_eden_top);
1260 Node *contention_check = new (C, 2) BoolNode(store_eden_top, BoolTest::ne);
1261 transform_later(contention_check);
1262 store_eden_top = new (C, 1) SCMemProjNode(store_eden_top);
1263 transform_later(store_eden_top);
1264
1265 // If not using TLABs, check to see if there was contention.
1266 IfNode *contention_iff = new (C, 2) IfNode (needgc_false, contention_check, PROB_MIN, COUNT_UNKNOWN);
1267 transform_later(contention_iff);
1268 Node *contention_true = new (C, 1) IfTrueNode(contention_iff);
1269 transform_later(contention_true);
1270 // If contention, loopback and try again.
1271 contended_region->init_req(contended_loopback_path, contention_true);
1272 contended_phi_rawmem->init_req(contended_loopback_path, store_eden_top);
1273
1274 // Fast-path succeeded with no contention!
1275 Node *contention_false = new (C, 1) IfFalseNode(contention_iff);
1276 transform_later(contention_false);
1277 fast_oop_ctrl = contention_false;
1278
1279 // Bump total allocated bytes for this thread
1280 Node* thread = new (C, 1) ThreadLocalNode();
1281 transform_later(thread);
1282 Node* alloc_bytes_adr = basic_plus_adr(top()/*not oop*/, thread,
1283 in_bytes(JavaThread::allocated_bytes_offset()));
1284 Node* alloc_bytes = make_load(fast_oop_ctrl, store_eden_top, alloc_bytes_adr,
1285 0, TypeLong::LONG, T_LONG);
1286 #ifdef _LP64
1287 Node* alloc_size = size_in_bytes;
1288 #else
1289 Node* alloc_size = new (C, 2) ConvI2LNode(size_in_bytes);
1290 transform_later(alloc_size);
1291 #endif
1292 Node* new_alloc_bytes = new (C, 3) AddLNode(alloc_bytes, alloc_size);
1293 transform_later(new_alloc_bytes);
1294 fast_oop_rawmem = make_store(fast_oop_ctrl, store_eden_top, alloc_bytes_adr,
1295 0, new_alloc_bytes, T_LONG);
1296 }
1297
1298 InitializeNode* init = alloc->initialization();
1299 fast_oop_rawmem = initialize_object(alloc,
1300 fast_oop_ctrl, fast_oop_rawmem, fast_oop,
1301 klass_node, length, size_in_bytes);
1302
1303 // If initialization is performed by an array copy, any required
1304 // MemBarStoreStore was already added. If the object does not
1305 // escape no need for a MemBarStoreStore. Otherwise we need a
1306 // MemBarStoreStore so that stores that initialize this object
1307 // can't be reordered with a subsequent store that makes this
1308 // object accessible by other threads.
1309 if (init == NULL || (!init->is_complete_with_arraycopy() && !init->does_not_escape())) {
1310 if (init == NULL || init->req() < InitializeNode::RawStores) {
1311 // No InitializeNode or no stores captured by zeroing
1312 // elimination. Simply add the MemBarStoreStore after object
1313 // initialization.
1314 MemBarNode* mb = MemBarNode::make(C, Op_MemBarStoreStore, Compile::AliasIdxBot, fast_oop_rawmem);
1315 transform_later(mb);
1316
1317 mb->init_req(TypeFunc::Memory, fast_oop_rawmem);
1318 mb->init_req(TypeFunc::Control, fast_oop_ctrl);
1319 fast_oop_ctrl = new (C, 1) ProjNode(mb,TypeFunc::Control);
1320 transform_later(fast_oop_ctrl);
1321 fast_oop_rawmem = new (C, 1) ProjNode(mb,TypeFunc::Memory);
1322 transform_later(fast_oop_rawmem);
1323 } else {
1324 // Add the MemBarStoreStore after the InitializeNode so that
1325 // all stores performing the initialization that were moved
1326 // before the InitializeNode happen before the storestore
1327 // barrier.
1328
1329 Node* init_ctrl = init->proj_out(TypeFunc::Control);
1330 Node* init_mem = init->proj_out(TypeFunc::Memory);
1331
1332 MemBarNode* mb = MemBarNode::make(C, Op_MemBarStoreStore, Compile::AliasIdxBot);
1333 transform_later(mb);
1334
1335 Node* ctrl = new (C, 1) ProjNode(init,TypeFunc::Control);
1336 transform_later(ctrl);
1337 Node* mem = new (C, 1) ProjNode(init,TypeFunc::Memory);
1338 transform_later(mem);
1339
1340 // The MemBarStoreStore depends on control and memory coming
1341 // from the InitializeNode
1342 mb->init_req(TypeFunc::Memory, mem);
1343 mb->init_req(TypeFunc::Control, ctrl);
1344
1345 ctrl = new (C, 1) ProjNode(mb,TypeFunc::Control);
1346 transform_later(ctrl);
1347 mem = new (C, 1) ProjNode(mb,TypeFunc::Memory);
1348 transform_later(mem);
1349
1350 // All nodes that depended on the InitializeNode for control
1351 // and memory must now depend on the MemBarNode that itself
1352 // depends on the InitializeNode
1353 _igvn.replace_node(init_ctrl, ctrl);
1354 _igvn.replace_node(init_mem, mem);
1355 }
1356 }
1357
1358 if (C->env()->dtrace_extended_probes()) {
1359 // Slow-path call
1360 int size = TypeFunc::Parms + 2;
1361 CallLeafNode *call = new (C, size) CallLeafNode(OptoRuntime::dtrace_object_alloc_Type(),
1362 CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_object_alloc_base),
1363 "dtrace_object_alloc",
1364 TypeRawPtr::BOTTOM);
1365
1366 // Get base of thread-local storage area
1367 Node* thread = new (C, 1) ThreadLocalNode();
1368 transform_later(thread);
1369
1370 call->init_req(TypeFunc::Parms+0, thread);
1371 call->init_req(TypeFunc::Parms+1, fast_oop);
1372 call->init_req(TypeFunc::Control, fast_oop_ctrl);
1373 call->init_req(TypeFunc::I_O , top()); // does no i/o
1374 call->init_req(TypeFunc::Memory , fast_oop_rawmem);
1375 call->init_req(TypeFunc::ReturnAdr, alloc->in(TypeFunc::ReturnAdr));
1376 call->init_req(TypeFunc::FramePtr, alloc->in(TypeFunc::FramePtr));
1377 transform_later(call);
1378 fast_oop_ctrl = new (C, 1) ProjNode(call,TypeFunc::Control);
1379 transform_later(fast_oop_ctrl);
1380 fast_oop_rawmem = new (C, 1) ProjNode(call,TypeFunc::Memory);
1381 transform_later(fast_oop_rawmem);
1382 }
1383
1384 // Plug in the successful fast-path into the result merge point
1385 result_region ->init_req(fast_result_path, fast_oop_ctrl);
1386 result_phi_rawoop->init_req(fast_result_path, fast_oop);
1387 result_phi_i_o ->init_req(fast_result_path, i_o);
1388 result_phi_rawmem->init_req(fast_result_path, fast_oop_rawmem);
1389 } else {
1390 slow_region = ctrl;
1391 result_phi_i_o = i_o; // Rename it to use in the following code.
1392 }
1393
1394 // Generate slow-path call
1395 CallNode *call = new (C, slow_call_type->domain()->cnt())
1396 CallStaticJavaNode(slow_call_type, slow_call_address,
1397 OptoRuntime::stub_name(slow_call_address),
1398 alloc->jvms()->bci(),
1399 TypePtr::BOTTOM);
1400 call->init_req( TypeFunc::Control, slow_region );
1401 call->init_req( TypeFunc::I_O , top() ) ; // does no i/o
1402 call->init_req( TypeFunc::Memory , slow_mem ); // may gc ptrs
1403 call->init_req( TypeFunc::ReturnAdr, alloc->in(TypeFunc::ReturnAdr) );
1404 call->init_req( TypeFunc::FramePtr, alloc->in(TypeFunc::FramePtr) );
1405
1406 call->init_req(TypeFunc::Parms+0, klass_node);
1407 if (length != NULL) {
1408 call->init_req(TypeFunc::Parms+1, length);
1409 }
1410
1411 // Copy debug information and adjust JVMState information, then replace
1412 // allocate node with the call
1413 copy_call_debug_info((CallNode *) alloc, call);
1414 if (!always_slow) {
1415 call->set_cnt(PROB_UNLIKELY_MAG(4)); // Same effect as RC_UNCOMMON.
1416 } else {
1417 // Hook i_o projection to avoid its elimination during allocation
1418 // replacement (when only a slow call is generated).
1419 call->set_req(TypeFunc::I_O, result_phi_i_o);
1420 }
1421 _igvn.replace_node(alloc, call);
1422 transform_later(call);
1423
1424 // Identify the output projections from the allocate node and
1425 // adjust any references to them.
1426 // The control and io projections look like:
1427 //
1428 // v---Proj(ctrl) <-----+ v---CatchProj(ctrl)
1429 // Allocate Catch
1430 // ^---Proj(io) <-------+ ^---CatchProj(io)
1431 //
1432 // We are interested in the CatchProj nodes.
1433 //
1434 extract_call_projections(call);
1435
1436 // An allocate node has separate memory projections for the uses on
1437 // the control and i_o paths. Replace the control memory projection with
1438 // result_phi_rawmem (unless we are only generating a slow call when
1439 // both memory projections are combined)
1440 if (!always_slow && _memproj_fallthrough != NULL) {
1441 for (DUIterator_Fast imax, i = _memproj_fallthrough->fast_outs(imax); i < imax; i++) {
1442 Node *use = _memproj_fallthrough->fast_out(i);
1443 _igvn.hash_delete(use);
1444 imax -= replace_input(use, _memproj_fallthrough, result_phi_rawmem);
1445 _igvn._worklist.push(use);
1446 // back up iterator
1447 --i;
1448 }
1449 }
1450 // Now change uses of _memproj_catchall to use _memproj_fallthrough and delete
1451 // _memproj_catchall so we end up with a call that has only 1 memory projection.
1452 if (_memproj_catchall != NULL ) {
1453 if (_memproj_fallthrough == NULL) {
1454 _memproj_fallthrough = new (C, 1) ProjNode(call, TypeFunc::Memory);
1455 transform_later(_memproj_fallthrough);
1456 }
1457 for (DUIterator_Fast imax, i = _memproj_catchall->fast_outs(imax); i < imax; i++) {
1458 Node *use = _memproj_catchall->fast_out(i);
1459 _igvn.hash_delete(use);
1460 imax -= replace_input(use, _memproj_catchall, _memproj_fallthrough);
1461 _igvn._worklist.push(use);
1462 // back up iterator
1463 --i;
1464 }
1465 assert(_memproj_catchall->outcnt() == 0, "all uses must be deleted");
1466 _igvn.remove_dead_node(_memproj_catchall);
1467 }
1468
1469 // An allocate node has separate i_o projections for the uses on the control
1470 // and i_o paths. Always replace the control i_o projection with result i_o
1471 // otherwise incoming i_o become dead when only a slow call is generated
1472 // (it is different from memory projections where both projections are
1473 // combined in such case).
1474 if (_ioproj_fallthrough != NULL) {
1475 for (DUIterator_Fast imax, i = _ioproj_fallthrough->fast_outs(imax); i < imax; i++) {
1476 Node *use = _ioproj_fallthrough->fast_out(i);
1477 _igvn.hash_delete(use);
1478 imax -= replace_input(use, _ioproj_fallthrough, result_phi_i_o);
1479 _igvn._worklist.push(use);
1480 // back up iterator
1481 --i;
1482 }
1483 }
1484 // Now change uses of _ioproj_catchall to use _ioproj_fallthrough and delete
1485 // _ioproj_catchall so we end up with a call that has only 1 i_o projection.
1486 if (_ioproj_catchall != NULL ) {
1487 if (_ioproj_fallthrough == NULL) {
1488 _ioproj_fallthrough = new (C, 1) ProjNode(call, TypeFunc::I_O);
1489 transform_later(_ioproj_fallthrough);
1490 }
1491 for (DUIterator_Fast imax, i = _ioproj_catchall->fast_outs(imax); i < imax; i++) {
1492 Node *use = _ioproj_catchall->fast_out(i);
1493 _igvn.hash_delete(use);
1494 imax -= replace_input(use, _ioproj_catchall, _ioproj_fallthrough);
1495 _igvn._worklist.push(use);
1496 // back up iterator
1497 --i;
1498 }
1499 assert(_ioproj_catchall->outcnt() == 0, "all uses must be deleted");
1500 _igvn.remove_dead_node(_ioproj_catchall);
1501 }
1502
1503 // if we generated only a slow call, we are done
1504 if (always_slow) {
1505 // Now we can unhook i_o.
1506 if (result_phi_i_o->outcnt() > 1) {
1507 call->set_req(TypeFunc::I_O, top());
1508 } else {
1509 assert(result_phi_i_o->unique_ctrl_out() == call, "");
1510 // Case of new array with negative size known during compilation.
1511 // AllocateArrayNode::Ideal() optimization disconnect unreachable
1512 // following code since call to runtime will throw exception.
1513 // As result there will be no users of i_o after the call.
1514 // Leave i_o attached to this call to avoid problems in preceding graph.
1515 }
1516 return;
1517 }
1518
1519
1520 if (_fallthroughcatchproj != NULL) {
1521 ctrl = _fallthroughcatchproj->clone();
1522 transform_later(ctrl);
1523 _igvn.replace_node(_fallthroughcatchproj, result_region);
1524 } else {
1525 ctrl = top();
1526 }
1527 Node *slow_result;
1528 if (_resproj == NULL) {
1529 // no uses of the allocation result
1530 slow_result = top();
1531 } else {
1532 slow_result = _resproj->clone();
1533 transform_later(slow_result);
1534 _igvn.replace_node(_resproj, result_phi_rawoop);
1535 }
1536
1537 // Plug slow-path into result merge point
1538 result_region ->init_req( slow_result_path, ctrl );
1539 result_phi_rawoop->init_req( slow_result_path, slow_result);
1540 result_phi_rawmem->init_req( slow_result_path, _memproj_fallthrough );
1541 transform_later(result_region);
1542 transform_later(result_phi_rawoop);
1543 transform_later(result_phi_rawmem);
1544 transform_later(result_phi_i_o);
1545 // This completes all paths into the result merge point
1546 }
1547
1548
1549 // Helper for PhaseMacroExpand::expand_allocate_common.
1550 // Initializes the newly-allocated storage.
1551 Node*
1552 PhaseMacroExpand::initialize_object(AllocateNode* alloc,
1553 Node* control, Node* rawmem, Node* object,
1554 Node* klass_node, Node* length,
1555 Node* size_in_bytes) {
1556 InitializeNode* init = alloc->initialization();
1557 // Store the klass & mark bits
1558 Node* mark_node = NULL;
1559 // For now only enable fast locking for non-array types
1560 if (UseBiasedLocking && (length == NULL)) {
1561 mark_node = make_load(control, rawmem, klass_node, in_bytes(Klass::prototype_header_offset()), TypeRawPtr::BOTTOM, T_ADDRESS);
1562 } else {
1563 mark_node = makecon(TypeRawPtr::make((address)markOopDesc::prototype()));
1564 }
1565 rawmem = make_store(control, rawmem, object, oopDesc::mark_offset_in_bytes(), mark_node, T_ADDRESS);
1566
1567 rawmem = make_store(control, rawmem, object, oopDesc::klass_offset_in_bytes(), klass_node, T_OBJECT);
1568 int header_size = alloc->minimum_header_size(); // conservatively small
1569
1570 // Array length
1571 if (length != NULL) { // Arrays need length field
1572 rawmem = make_store(control, rawmem, object, arrayOopDesc::length_offset_in_bytes(), length, T_INT);
1573 // conservatively small header size:
1574 header_size = arrayOopDesc::base_offset_in_bytes(T_BYTE);
1575 ciKlass* k = _igvn.type(klass_node)->is_klassptr()->klass();
1576 if (k->is_array_klass()) // we know the exact header size in most cases:
1577 header_size = Klass::layout_helper_header_size(k->layout_helper());
1578 }
1579
1580 // Clear the object body, if necessary.
1581 if (init == NULL) {
1582 // The init has somehow disappeared; be cautious and clear everything.
1583 //
1584 // This can happen if a node is allocated but an uncommon trap occurs
1585 // immediately. In this case, the Initialize gets associated with the
1586 // trap, and may be placed in a different (outer) loop, if the Allocate
1587 // is in a loop. If (this is rare) the inner loop gets unrolled, then
1588 // there can be two Allocates to one Initialize. The answer in all these
1589 // edge cases is safety first. It is always safe to clear immediately
1590 // within an Allocate, and then (maybe or maybe not) clear some more later.
1591 if (!ZeroTLAB)
1592 rawmem = ClearArrayNode::clear_memory(control, rawmem, object,
1593 header_size, size_in_bytes,
1594 &_igvn);
1595 } else {
1596 if (!init->is_complete()) {
1597 // Try to win by zeroing only what the init does not store.
1598 // We can also try to do some peephole optimizations,
1599 // such as combining some adjacent subword stores.
1600 rawmem = init->complete_stores(control, rawmem, object,
1601 header_size, size_in_bytes, &_igvn);
1602 }
1603 // We have no more use for this link, since the AllocateNode goes away:
1604 init->set_req(InitializeNode::RawAddress, top());
1605 // (If we keep the link, it just confuses the register allocator,
1606 // who thinks he sees a real use of the address by the membar.)
1607 }
1608
1609 return rawmem;
1610 }
1611
1612 // Generate prefetch instructions for next allocations.
1613 Node* PhaseMacroExpand::prefetch_allocation(Node* i_o, Node*& needgc_false,
1614 Node*& contended_phi_rawmem,
1615 Node* old_eden_top, Node* new_eden_top,
1616 Node* length) {
1617 enum { fall_in_path = 1, pf_path = 2 };
1618 if( UseTLAB && AllocatePrefetchStyle == 2 ) {
1619 // Generate prefetch allocation with watermark check.
1620 // As an allocation hits the watermark, we will prefetch starting
1621 // at a "distance" away from watermark.
1622
1623 Node *pf_region = new (C, 3) RegionNode(3);
1624 Node *pf_phi_rawmem = new (C, 3) PhiNode( pf_region, Type::MEMORY,
1625 TypeRawPtr::BOTTOM );
1626 // I/O is used for Prefetch
1627 Node *pf_phi_abio = new (C, 3) PhiNode( pf_region, Type::ABIO );
1628
1629 Node *thread = new (C, 1) ThreadLocalNode();
1630 transform_later(thread);
1631
1632 Node *eden_pf_adr = new (C, 4) AddPNode( top()/*not oop*/, thread,
1633 _igvn.MakeConX(in_bytes(JavaThread::tlab_pf_top_offset())) );
1634 transform_later(eden_pf_adr);
1635
1636 Node *old_pf_wm = new (C, 3) LoadPNode( needgc_false,
1637 contended_phi_rawmem, eden_pf_adr,
1638 TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM );
1639 transform_later(old_pf_wm);
1640
1641 // check against new_eden_top
1642 Node *need_pf_cmp = new (C, 3) CmpPNode( new_eden_top, old_pf_wm );
1643 transform_later(need_pf_cmp);
1644 Node *need_pf_bol = new (C, 2) BoolNode( need_pf_cmp, BoolTest::ge );
1645 transform_later(need_pf_bol);
1646 IfNode *need_pf_iff = new (C, 2) IfNode( needgc_false, need_pf_bol,
1647 PROB_UNLIKELY_MAG(4), COUNT_UNKNOWN );
1648 transform_later(need_pf_iff);
1649
1650 // true node, add prefetchdistance
1651 Node *need_pf_true = new (C, 1) IfTrueNode( need_pf_iff );
1652 transform_later(need_pf_true);
1653
1654 Node *need_pf_false = new (C, 1) IfFalseNode( need_pf_iff );
1655 transform_later(need_pf_false);
1656
1657 Node *new_pf_wmt = new (C, 4) AddPNode( top(), old_pf_wm,
1658 _igvn.MakeConX(AllocatePrefetchDistance) );
1659 transform_later(new_pf_wmt );
1660 new_pf_wmt->set_req(0, need_pf_true);
1661
1662 Node *store_new_wmt = new (C, 4) StorePNode( need_pf_true,
1663 contended_phi_rawmem, eden_pf_adr,
1664 TypeRawPtr::BOTTOM, new_pf_wmt );
1665 transform_later(store_new_wmt);
1666
1667 // adding prefetches
1668 pf_phi_abio->init_req( fall_in_path, i_o );
1669
1670 Node *prefetch_adr;
1671 Node *prefetch;
1672 uint lines = AllocatePrefetchDistance / AllocatePrefetchStepSize;
1673 uint step_size = AllocatePrefetchStepSize;
1674 uint distance = 0;
1675
1676 for ( uint i = 0; i < lines; i++ ) {
1677 prefetch_adr = new (C, 4) AddPNode( old_pf_wm, new_pf_wmt,
1678 _igvn.MakeConX(distance) );
1679 transform_later(prefetch_adr);
1680 prefetch = new (C, 3) PrefetchAllocationNode( i_o, prefetch_adr );
1681 transform_later(prefetch);
1682 distance += step_size;
1683 i_o = prefetch;
1684 }
1685 pf_phi_abio->set_req( pf_path, i_o );
1686
1687 pf_region->init_req( fall_in_path, need_pf_false );
1688 pf_region->init_req( pf_path, need_pf_true );
1689
1690 pf_phi_rawmem->init_req( fall_in_path, contended_phi_rawmem );
1691 pf_phi_rawmem->init_req( pf_path, store_new_wmt );
1692
1693 transform_later(pf_region);
1694 transform_later(pf_phi_rawmem);
1695 transform_later(pf_phi_abio);
1696
1697 needgc_false = pf_region;
1698 contended_phi_rawmem = pf_phi_rawmem;
1699 i_o = pf_phi_abio;
1700 } else if( UseTLAB && AllocatePrefetchStyle == 3 ) {
1701 // Insert a prefetch for each allocation.
1702 // This code is used for Sparc with BIS.
1703 Node *pf_region = new (C, 3) RegionNode(3);
1704 Node *pf_phi_rawmem = new (C, 3) PhiNode( pf_region, Type::MEMORY,
1705 TypeRawPtr::BOTTOM );
1706
1707 // Generate several prefetch instructions.
1708 uint lines = (length != NULL) ? AllocatePrefetchLines : AllocateInstancePrefetchLines;
1709 uint step_size = AllocatePrefetchStepSize;
1710 uint distance = AllocatePrefetchDistance;
1711
1712 // Next cache address.
1713 Node *cache_adr = new (C, 4) AddPNode(old_eden_top, old_eden_top,
1714 _igvn.MakeConX(distance));
1715 transform_later(cache_adr);
1716 cache_adr = new (C, 2) CastP2XNode(needgc_false, cache_adr);
1717 transform_later(cache_adr);
1718 Node* mask = _igvn.MakeConX(~(intptr_t)(step_size-1));
1719 cache_adr = new (C, 3) AndXNode(cache_adr, mask);
1720 transform_later(cache_adr);
1721 cache_adr = new (C, 2) CastX2PNode(cache_adr);
1722 transform_later(cache_adr);
1723
1724 // Prefetch
1725 Node *prefetch = new (C, 3) PrefetchAllocationNode( contended_phi_rawmem, cache_adr );
1726 prefetch->set_req(0, needgc_false);
1727 transform_later(prefetch);
1728 contended_phi_rawmem = prefetch;
1729 Node *prefetch_adr;
1730 distance = step_size;
1731 for ( uint i = 1; i < lines; i++ ) {
1732 prefetch_adr = new (C, 4) AddPNode( cache_adr, cache_adr,
1733 _igvn.MakeConX(distance) );
1734 transform_later(prefetch_adr);
1735 prefetch = new (C, 3) PrefetchAllocationNode( contended_phi_rawmem, prefetch_adr );
1736 transform_later(prefetch);
1737 distance += step_size;
1738 contended_phi_rawmem = prefetch;
1739 }
1740 } else if( AllocatePrefetchStyle > 0 ) {
1741 // Insert a prefetch for each allocation only on the fast-path
1742 Node *prefetch_adr;
1743 Node *prefetch;
1744 // Generate several prefetch instructions.
1745 uint lines = (length != NULL) ? AllocatePrefetchLines : AllocateInstancePrefetchLines;
1746 uint step_size = AllocatePrefetchStepSize;
1747 uint distance = AllocatePrefetchDistance;
1748 for ( uint i = 0; i < lines; i++ ) {
1749 prefetch_adr = new (C, 4) AddPNode( old_eden_top, new_eden_top,
1750 _igvn.MakeConX(distance) );
1751 transform_later(prefetch_adr);
1752 prefetch = new (C, 3) PrefetchAllocationNode( i_o, prefetch_adr );
1753 // Do not let it float too high, since if eden_top == eden_end,
1754 // both might be null.
1755 if( i == 0 ) { // Set control for first prefetch, next follows it
1756 prefetch->init_req(0, needgc_false);
1757 }
1758 transform_later(prefetch);
1759 distance += step_size;
1760 i_o = prefetch;
1761 }
1762 }
1763 return i_o;
1764 }
1765
1766
1767 void PhaseMacroExpand::expand_allocate(AllocateNode *alloc) {
1768 expand_allocate_common(alloc, NULL,
1769 OptoRuntime::new_instance_Type(),
1770 OptoRuntime::new_instance_Java());
1771 }
1772
1773 void PhaseMacroExpand::expand_allocate_array(AllocateArrayNode *alloc) {
1774 Node* length = alloc->in(AllocateNode::ALength);
1775 InitializeNode* init = alloc->initialization();
1776 Node* klass_node = alloc->in(AllocateNode::KlassNode);
1777 ciKlass* k = _igvn.type(klass_node)->is_klassptr()->klass();
1778 address slow_call_address; // Address of slow call
1779 if (init != NULL && init->is_complete_with_arraycopy() &&
1780 k->is_type_array_klass()) {
1781 // Don't zero type array during slow allocation in VM since
1782 // it will be initialized later by arraycopy in compiled code.
1783 slow_call_address = OptoRuntime::new_array_nozero_Java();
1784 } else {
1785 slow_call_address = OptoRuntime::new_array_Java();
1786 }
1787 expand_allocate_common(alloc, length,
1788 OptoRuntime::new_array_Type(),
1789 slow_call_address);
1790 }
1791
1792 //-----------------------mark_eliminated_locking_nodes-----------------------
1793 // During EA obj may point to several objects but after few ideal graph
1794 // transformations (CCP) it may point to only one non escaping object
1795 // (but still using phi), corresponding locks and unlocks will be marked
1796 // for elimination. Later obj could be replaced with a new node (new phi)
1797 // and which does not have escape information. And later after some graph
1798 // reshape other locks and unlocks (which were not marked for elimination
1799 // before) are connected to this new obj (phi) but they still will not be
1800 // marked for elimination since new obj has no escape information.
1801 // Mark all associated (same box and obj) lock and unlock nodes for
1802 // elimination if some of them marked already.
1803 void PhaseMacroExpand::mark_eliminated_locking_nodes(AbstractLockNode *alock) {
1804 if (!alock->is_eliminated()) {
1805 return;
1806 }
1807 if (!alock->is_coarsened()) { // Eliminated by EA
1808 // Create new "eliminated" BoxLock node and use it
1809 // in monitor debug info for the same object.
1810 BoxLockNode* oldbox = alock->box_node()->as_BoxLock();
1811 Node* obj = alock->obj_node();
1812 if (!oldbox->is_eliminated()) {
1813 BoxLockNode* newbox = oldbox->clone()->as_BoxLock();
1814 // Note: BoxLock node is marked eliminated only here
1815 // and it is used to indicate that all associated lock
1816 // and unlock nodes are marked for elimination.
1817 newbox->set_eliminated();
1818 transform_later(newbox);
1819 // Replace old box node with new box for all users
1820 // of the same object.
1821 for (uint i = 0; i < oldbox->outcnt();) {
1822
1823 bool next_edge = true;
1824 Node* u = oldbox->raw_out(i);
1825 if (u->is_AbstractLock() &&
1826 u->as_AbstractLock()->obj_node() == obj &&
1827 u->as_AbstractLock()->box_node() == oldbox) {
1828 // Mark all associated locks and unlocks.
1829 u->as_AbstractLock()->set_eliminated();
1830 _igvn.hash_delete(u);
1831 u->set_req(TypeFunc::Parms + 1, newbox);
1832 next_edge = false;
1833 }
1834 // Replace old box in monitor debug info.
1835 if (u->is_SafePoint() && u->as_SafePoint()->jvms()) {
1836 SafePointNode* sfn = u->as_SafePoint();
1837 JVMState* youngest_jvms = sfn->jvms();
1838 int max_depth = youngest_jvms->depth();
1839 for (int depth = 1; depth <= max_depth; depth++) {
1840 JVMState* jvms = youngest_jvms->of_depth(depth);
1841 int num_mon = jvms->nof_monitors();
1842 // Loop over monitors
1843 for (int idx = 0; idx < num_mon; idx++) {
1844 Node* obj_node = sfn->monitor_obj(jvms, idx);
1845 Node* box_node = sfn->monitor_box(jvms, idx);
1846 if (box_node == oldbox && obj_node == obj) {
1847 int j = jvms->monitor_box_offset(idx);
1848 _igvn.hash_delete(u);
1849 u->set_req(j, newbox);
1850 next_edge = false;
1851 }
1852 } // for (int idx = 0;
1853 } // for (int depth = 1;
1854 } // if (u->is_SafePoint()
1855 if (next_edge) i++;
1856 } // for (uint i = 0; i < oldbox->outcnt();)
1857 } // if (!oldbox->is_eliminated())
1858 } // if (!alock->is_coarsened())
1859 }
1860
1861 // we have determined that this lock/unlock can be eliminated, we simply
1862 // eliminate the node without expanding it.
1863 //
1864 // Note: The membar's associated with the lock/unlock are currently not
1865 // eliminated. This should be investigated as a future enhancement.
1866 //
1867 bool PhaseMacroExpand::eliminate_locking_node(AbstractLockNode *alock) {
1868
1869 if (!alock->is_eliminated()) {
1870 return false;
1871 }
1872 #ifdef ASSERT
1873 if (alock->is_Lock() && !alock->is_coarsened()) {
1874 // Check that new "eliminated" BoxLock node is created.
1875 BoxLockNode* oldbox = alock->box_node()->as_BoxLock();
1876 assert(oldbox->is_eliminated(), "should be done already");
1877 }
1878 #endif
1879 CompileLog* log = C->log();
1880 if (log != NULL) {
1881 log->head("eliminate_lock lock='%d'",
1882 alock->is_Lock());
1883 JVMState* p = alock->jvms();
1884 while (p != NULL) {
1885 log->elem("jvms bci='%d' method='%d'", p->bci(), log->identify(p->method()));
1886 p = p->caller();
1887 }
1888 log->tail("eliminate_lock");
1889 }
1890
1891 #ifndef PRODUCT
1892 if (PrintEliminateLocks) {
1893 if (alock->is_Lock()) {
1894 tty->print_cr("++++ Eliminated: %d Lock", alock->_idx);
1895 } else {
1896 tty->print_cr("++++ Eliminated: %d Unlock", alock->_idx);
1897 }
1898 }
1899 #endif
1900
1901 Node* mem = alock->in(TypeFunc::Memory);
1902 Node* ctrl = alock->in(TypeFunc::Control);
1903
1904 extract_call_projections(alock);
1905 // There are 2 projections from the lock. The lock node will
1906 // be deleted when its last use is subsumed below.
1907 assert(alock->outcnt() == 2 &&
1908 _fallthroughproj != NULL &&
1909 _memproj_fallthrough != NULL,
1910 "Unexpected projections from Lock/Unlock");
1911
1912 Node* fallthroughproj = _fallthroughproj;
1913 Node* memproj_fallthrough = _memproj_fallthrough;
1914
1915 // The memory projection from a lock/unlock is RawMem
1916 // The input to a Lock is merged memory, so extract its RawMem input
1917 // (unless the MergeMem has been optimized away.)
1918 if (alock->is_Lock()) {
1919 // Seach for MemBarAcquireLock node and delete it also.
1920 MemBarNode* membar = fallthroughproj->unique_ctrl_out()->as_MemBar();
1921 assert(membar != NULL && membar->Opcode() == Op_MemBarAcquireLock, "");
1922 Node* ctrlproj = membar->proj_out(TypeFunc::Control);
1923 Node* memproj = membar->proj_out(TypeFunc::Memory);
1924 _igvn.replace_node(ctrlproj, fallthroughproj);
1925 _igvn.replace_node(memproj, memproj_fallthrough);
1926
1927 // Delete FastLock node also if this Lock node is unique user
1928 // (a loop peeling may clone a Lock node).
1929 Node* flock = alock->as_Lock()->fastlock_node();
1930 if (flock->outcnt() == 1) {
1931 assert(flock->unique_out() == alock, "sanity");
1932 _igvn.replace_node(flock, top());
1933 }
1934 }
1935
1936 // Seach for MemBarReleaseLock node and delete it also.
1937 if (alock->is_Unlock() && ctrl != NULL && ctrl->is_Proj() &&
1938 ctrl->in(0)->is_MemBar()) {
1939 MemBarNode* membar = ctrl->in(0)->as_MemBar();
1940 assert(membar->Opcode() == Op_MemBarReleaseLock &&
1941 mem->is_Proj() && membar == mem->in(0), "");
1942 _igvn.replace_node(fallthroughproj, ctrl);
1943 _igvn.replace_node(memproj_fallthrough, mem);
1944 fallthroughproj = ctrl;
1945 memproj_fallthrough = mem;
1946 ctrl = membar->in(TypeFunc::Control);
1947 mem = membar->in(TypeFunc::Memory);
1948 }
1949
1950 _igvn.replace_node(fallthroughproj, ctrl);
1951 _igvn.replace_node(memproj_fallthrough, mem);
1952 return true;
1953 }
1954
1955
1956 //------------------------------expand_lock_node----------------------
1957 void PhaseMacroExpand::expand_lock_node(LockNode *lock) {
1958
1959 Node* ctrl = lock->in(TypeFunc::Control);
1960 Node* mem = lock->in(TypeFunc::Memory);
1961 Node* obj = lock->obj_node();
1962 Node* box = lock->box_node();
1963 Node* flock = lock->fastlock_node();
1964
1965 // Make the merge point
1966 Node *region;
1967 Node *mem_phi;
1968 Node *slow_path;
1969
1970 if (UseOptoBiasInlining) {
1971 /*
1972 * See the full description in MacroAssembler::biased_locking_enter().
1973 *
1974 * if( (mark_word & biased_lock_mask) == biased_lock_pattern ) {
1975 * // The object is biased.
1976 * proto_node = klass->prototype_header;
1977 * o_node = thread | proto_node;
1978 * x_node = o_node ^ mark_word;
1979 * if( (x_node & ~age_mask) == 0 ) { // Biased to the current thread ?
1980 * // Done.
1981 * } else {
1982 * if( (x_node & biased_lock_mask) != 0 ) {
1983 * // The klass's prototype header is no longer biased.
1984 * cas(&mark_word, mark_word, proto_node)
1985 * goto cas_lock;
1986 * } else {
1987 * // The klass's prototype header is still biased.
1988 * if( (x_node & epoch_mask) != 0 ) { // Expired epoch?
1989 * old = mark_word;
1990 * new = o_node;
1991 * } else {
1992 * // Different thread or anonymous biased.
1993 * old = mark_word & (epoch_mask | age_mask | biased_lock_mask);
1994 * new = thread | old;
1995 * }
1996 * // Try to rebias.
1997 * if( cas(&mark_word, old, new) == 0 ) {
1998 * // Done.
1999 * } else {
2000 * goto slow_path; // Failed.
2001 * }
2002 * }
2003 * }
2004 * } else {
2005 * // The object is not biased.
2006 * cas_lock:
2007 * if( FastLock(obj) == 0 ) {
2008 * // Done.
2009 * } else {
2010 * slow_path:
2011 * OptoRuntime::complete_monitor_locking_Java(obj);
2012 * }
2013 * }
2014 */
2015
2016 region = new (C, 5) RegionNode(5);
2017 // create a Phi for the memory state
2018 mem_phi = new (C, 5) PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM);
2019
2020 Node* fast_lock_region = new (C, 3) RegionNode(3);
2021 Node* fast_lock_mem_phi = new (C, 3) PhiNode( fast_lock_region, Type::MEMORY, TypeRawPtr::BOTTOM);
2022
2023 // First, check mark word for the biased lock pattern.
2024 Node* mark_node = make_load(ctrl, mem, obj, oopDesc::mark_offset_in_bytes(), TypeX_X, TypeX_X->basic_type());
2025
2026 // Get fast path - mark word has the biased lock pattern.
2027 ctrl = opt_bits_test(ctrl, fast_lock_region, 1, mark_node,
2028 markOopDesc::biased_lock_mask_in_place,
2029 markOopDesc::biased_lock_pattern, true);
2030 // fast_lock_region->in(1) is set to slow path.
2031 fast_lock_mem_phi->init_req(1, mem);
2032
2033 // Now check that the lock is biased to the current thread and has
2034 // the same epoch and bias as Klass::_prototype_header.
2035
2036 // Special-case a fresh allocation to avoid building nodes:
2037 Node* klass_node = AllocateNode::Ideal_klass(obj, &_igvn);
2038 if (klass_node == NULL) {
2039 Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes());
2040 klass_node = transform_later( LoadKlassNode::make(_igvn, mem, k_adr, _igvn.type(k_adr)->is_ptr()) );
2041 #ifdef _LP64
2042 if (UseCompressedOops && klass_node->is_DecodeN()) {
2043 assert(klass_node->in(1)->Opcode() == Op_LoadNKlass, "sanity");
2044 klass_node->in(1)->init_req(0, ctrl);
2045 } else
2046 #endif
2047 klass_node->init_req(0, ctrl);
2048 }
2049 Node *proto_node = make_load(ctrl, mem, klass_node, in_bytes(Klass::prototype_header_offset()), TypeX_X, TypeX_X->basic_type());
2050
2051 Node* thread = transform_later(new (C, 1) ThreadLocalNode());
2052 Node* cast_thread = transform_later(new (C, 2) CastP2XNode(ctrl, thread));
2053 Node* o_node = transform_later(new (C, 3) OrXNode(cast_thread, proto_node));
2054 Node* x_node = transform_later(new (C, 3) XorXNode(o_node, mark_node));
2055
2056 // Get slow path - mark word does NOT match the value.
2057 Node* not_biased_ctrl = opt_bits_test(ctrl, region, 3, x_node,
2058 (~markOopDesc::age_mask_in_place), 0);
2059 // region->in(3) is set to fast path - the object is biased to the current thread.
2060 mem_phi->init_req(3, mem);
2061
2062
2063 // Mark word does NOT match the value (thread | Klass::_prototype_header).
2064
2065
2066 // First, check biased pattern.
2067 // Get fast path - _prototype_header has the same biased lock pattern.
2068 ctrl = opt_bits_test(not_biased_ctrl, fast_lock_region, 2, x_node,
2069 markOopDesc::biased_lock_mask_in_place, 0, true);
2070
2071 not_biased_ctrl = fast_lock_region->in(2); // Slow path
2072 // fast_lock_region->in(2) - the prototype header is no longer biased
2073 // and we have to revoke the bias on this object.
2074 // We are going to try to reset the mark of this object to the prototype
2075 // value and fall through to the CAS-based locking scheme.
2076 Node* adr = basic_plus_adr(obj, oopDesc::mark_offset_in_bytes());
2077 Node* cas = new (C, 5) StoreXConditionalNode(not_biased_ctrl, mem, adr,
2078 proto_node, mark_node);
2079 transform_later(cas);
2080 Node* proj = transform_later( new (C, 1) SCMemProjNode(cas));
2081 fast_lock_mem_phi->init_req(2, proj);
2082
2083
2084 // Second, check epoch bits.
2085 Node* rebiased_region = new (C, 3) RegionNode(3);
2086 Node* old_phi = new (C, 3) PhiNode( rebiased_region, TypeX_X);
2087 Node* new_phi = new (C, 3) PhiNode( rebiased_region, TypeX_X);
2088
2089 // Get slow path - mark word does NOT match epoch bits.
2090 Node* epoch_ctrl = opt_bits_test(ctrl, rebiased_region, 1, x_node,
2091 markOopDesc::epoch_mask_in_place, 0);
2092 // The epoch of the current bias is not valid, attempt to rebias the object
2093 // toward the current thread.
2094 rebiased_region->init_req(2, epoch_ctrl);
2095 old_phi->init_req(2, mark_node);
2096 new_phi->init_req(2, o_node);
2097
2098 // rebiased_region->in(1) is set to fast path.
2099 // The epoch of the current bias is still valid but we know
2100 // nothing about the owner; it might be set or it might be clear.
2101 Node* cmask = MakeConX(markOopDesc::biased_lock_mask_in_place |
2102 markOopDesc::age_mask_in_place |
2103 markOopDesc::epoch_mask_in_place);
2104 Node* old = transform_later(new (C, 3) AndXNode(mark_node, cmask));
2105 cast_thread = transform_later(new (C, 2) CastP2XNode(ctrl, thread));
2106 Node* new_mark = transform_later(new (C, 3) OrXNode(cast_thread, old));
2107 old_phi->init_req(1, old);
2108 new_phi->init_req(1, new_mark);
2109
2110 transform_later(rebiased_region);
2111 transform_later(old_phi);
2112 transform_later(new_phi);
2113
2114 // Try to acquire the bias of the object using an atomic operation.
2115 // If this fails we will go in to the runtime to revoke the object's bias.
2116 cas = new (C, 5) StoreXConditionalNode(rebiased_region, mem, adr,
2117 new_phi, old_phi);
2118 transform_later(cas);
2119 proj = transform_later( new (C, 1) SCMemProjNode(cas));
2120
2121 // Get slow path - Failed to CAS.
2122 not_biased_ctrl = opt_bits_test(rebiased_region, region, 4, cas, 0, 0);
2123 mem_phi->init_req(4, proj);
2124 // region->in(4) is set to fast path - the object is rebiased to the current thread.
2125
2126 // Failed to CAS.
2127 slow_path = new (C, 3) RegionNode(3);
2128 Node *slow_mem = new (C, 3) PhiNode( slow_path, Type::MEMORY, TypeRawPtr::BOTTOM);
2129
2130 slow_path->init_req(1, not_biased_ctrl); // Capture slow-control
2131 slow_mem->init_req(1, proj);
2132
2133 // Call CAS-based locking scheme (FastLock node).
2134
2135 transform_later(fast_lock_region);
2136 transform_later(fast_lock_mem_phi);
2137
2138 // Get slow path - FastLock failed to lock the object.
2139 ctrl = opt_bits_test(fast_lock_region, region, 2, flock, 0, 0);
2140 mem_phi->init_req(2, fast_lock_mem_phi);
2141 // region->in(2) is set to fast path - the object is locked to the current thread.
2142
2143 slow_path->init_req(2, ctrl); // Capture slow-control
2144 slow_mem->init_req(2, fast_lock_mem_phi);
2145
2146 transform_later(slow_path);
2147 transform_later(slow_mem);
2148 // Reset lock's memory edge.
2149 lock->set_req(TypeFunc::Memory, slow_mem);
2150
2151 } else {
2152 region = new (C, 3) RegionNode(3);
2153 // create a Phi for the memory state
2154 mem_phi = new (C, 3) PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM);
2155
2156 // Optimize test; set region slot 2
2157 slow_path = opt_bits_test(ctrl, region, 2, flock, 0, 0);
2158 mem_phi->init_req(2, mem);
2159 }
2160
2161 // Make slow path call
2162 CallNode *call = make_slow_call( (CallNode *) lock, OptoRuntime::complete_monitor_enter_Type(), OptoRuntime::complete_monitor_locking_Java(), NULL, slow_path, obj, box );
2163
2164 extract_call_projections(call);
2165
2166 // Slow path can only throw asynchronous exceptions, which are always
2167 // de-opted. So the compiler thinks the slow-call can never throw an
2168 // exception. If it DOES throw an exception we would need the debug
2169 // info removed first (since if it throws there is no monitor).
2170 assert ( _ioproj_fallthrough == NULL && _ioproj_catchall == NULL &&
2171 _memproj_catchall == NULL && _catchallcatchproj == NULL, "Unexpected projection from Lock");
2172
2173 // Capture slow path
2174 // disconnect fall-through projection from call and create a new one
2175 // hook up users of fall-through projection to region
2176 Node *slow_ctrl = _fallthroughproj->clone();
2177 transform_later(slow_ctrl);
2178 _igvn.hash_delete(_fallthroughproj);
2179 _fallthroughproj->disconnect_inputs(NULL);
2180 region->init_req(1, slow_ctrl);
2181 // region inputs are now complete
2182 transform_later(region);
2183 _igvn.replace_node(_fallthroughproj, region);
2184
2185 Node *memproj = transform_later( new(C, 1) ProjNode(call, TypeFunc::Memory) );
2186 mem_phi->init_req(1, memproj );
2187 transform_later(mem_phi);
2188 _igvn.replace_node(_memproj_fallthrough, mem_phi);
2189 }
2190
2191 //------------------------------expand_unlock_node----------------------
2192 void PhaseMacroExpand::expand_unlock_node(UnlockNode *unlock) {
2193
2194 Node* ctrl = unlock->in(TypeFunc::Control);
2195 Node* mem = unlock->in(TypeFunc::Memory);
2196 Node* obj = unlock->obj_node();
2197 Node* box = unlock->box_node();
2198
2199 // No need for a null check on unlock
2200
2201 // Make the merge point
2202 Node *region;
2203 Node *mem_phi;
2204
2205 if (UseOptoBiasInlining) {
2206 // Check for biased locking unlock case, which is a no-op.
2207 // See the full description in MacroAssembler::biased_locking_exit().
2208 region = new (C, 4) RegionNode(4);
2209 // create a Phi for the memory state
2210 mem_phi = new (C, 4) PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM);
2211 mem_phi->init_req(3, mem);
2212
2213 Node* mark_node = make_load(ctrl, mem, obj, oopDesc::mark_offset_in_bytes(), TypeX_X, TypeX_X->basic_type());
2214 ctrl = opt_bits_test(ctrl, region, 3, mark_node,
2215 markOopDesc::biased_lock_mask_in_place,
2216 markOopDesc::biased_lock_pattern);
2217 } else {
2218 region = new (C, 3) RegionNode(3);
2219 // create a Phi for the memory state
2220 mem_phi = new (C, 3) PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM);
2221 }
2222
2223 FastUnlockNode *funlock = new (C, 3) FastUnlockNode( ctrl, obj, box );
2224 funlock = transform_later( funlock )->as_FastUnlock();
2225 // Optimize test; set region slot 2
2226 Node *slow_path = opt_bits_test(ctrl, region, 2, funlock, 0, 0);
2227
2228 CallNode *call = make_slow_call( (CallNode *) unlock, OptoRuntime::complete_monitor_exit_Type(), CAST_FROM_FN_PTR(address, SharedRuntime::complete_monitor_unlocking_C), "complete_monitor_unlocking_C", slow_path, obj, box );
2229
2230 extract_call_projections(call);
2231
2232 assert ( _ioproj_fallthrough == NULL && _ioproj_catchall == NULL &&
2233 _memproj_catchall == NULL && _catchallcatchproj == NULL, "Unexpected projection from Lock");
2234
2235 // No exceptions for unlocking
2236 // Capture slow path
2237 // disconnect fall-through projection from call and create a new one
2238 // hook up users of fall-through projection to region
2239 Node *slow_ctrl = _fallthroughproj->clone();
2240 transform_later(slow_ctrl);
2241 _igvn.hash_delete(_fallthroughproj);
2242 _fallthroughproj->disconnect_inputs(NULL);
2243 region->init_req(1, slow_ctrl);
2244 // region inputs are now complete
2245 transform_later(region);
2246 _igvn.replace_node(_fallthroughproj, region);
2247
2248 Node *memproj = transform_later( new(C, 1) ProjNode(call, TypeFunc::Memory) );
2249 mem_phi->init_req(1, memproj );
2250 mem_phi->init_req(2, mem);
2251 transform_later(mem_phi);
2252 _igvn.replace_node(_memproj_fallthrough, mem_phi);
2253 }
2254
2255 //---------------------------eliminate_macro_nodes----------------------
2256 // Eliminate scalar replaced allocations and associated locks.
2257 void PhaseMacroExpand::eliminate_macro_nodes() {
2258 if (C->macro_count() == 0)
2259 return;
2260
2261 // First, attempt to eliminate locks
2262 int cnt = C->macro_count();
2263 for (int i=0; i < cnt; i++) {
2264 Node *n = C->macro_node(i);
2265 if (n->is_AbstractLock()) { // Lock and Unlock nodes
2266 // Before elimination mark all associated (same box and obj)
2267 // lock and unlock nodes.
2268 mark_eliminated_locking_nodes(n->as_AbstractLock());
2269 }
2270 }
2271 bool progress = true;
2272 while (progress) {
2273 progress = false;
2274 for (int i = C->macro_count(); i > 0; i--) {
2275 Node * n = C->macro_node(i-1);
2276 bool success = false;
2277 debug_only(int old_macro_count = C->macro_count(););
2278 if (n->is_AbstractLock()) {
2279 success = eliminate_locking_node(n->as_AbstractLock());
2280 }
2281 assert(success == (C->macro_count() < old_macro_count), "elimination reduces macro count");
2282 progress = progress || success;
2283 }
2284 }
2285 // Next, attempt to eliminate allocations
2286 progress = true;
2287 while (progress) {
2288 progress = false;
2289 for (int i = C->macro_count(); i > 0; i--) {
2290 Node * n = C->macro_node(i-1);
2291 bool success = false;
2292 debug_only(int old_macro_count = C->macro_count(););
2293 switch (n->class_id()) {
2294 case Node::Class_Allocate:
2295 case Node::Class_AllocateArray:
2296 success = eliminate_allocate_node(n->as_Allocate());
2297 break;
2298 case Node::Class_Lock:
2299 case Node::Class_Unlock:
2300 assert(!n->as_AbstractLock()->is_eliminated(), "sanity");
2301 break;
2302 default:
2303 assert(n->Opcode() == Op_LoopLimit ||
2304 n->Opcode() == Op_Opaque1 ||
2305 n->Opcode() == Op_Opaque2, "unknown node type in macro list");
2306 }
2307 assert(success == (C->macro_count() < old_macro_count), "elimination reduces macro count");
2308 progress = progress || success;
2309 }
2310 }
2311 }
2312
2313 //------------------------------expand_macro_nodes----------------------
2314 // Returns true if a failure occurred.
2315 bool PhaseMacroExpand::expand_macro_nodes() {
2316 // Last attempt to eliminate macro nodes.
2317 eliminate_macro_nodes();
2318
2319 // Make sure expansion will not cause node limit to be exceeded.
2320 // Worst case is a macro node gets expanded into about 50 nodes.
2321 // Allow 50% more for optimization.
2322 if (C->check_node_count(C->macro_count() * 75, "out of nodes before macro expansion" ) )
2323 return true;
2324
2325 // Eliminate Opaque and LoopLimit nodes. Do it after all loop optimizations.
2326 bool progress = true;
2327 while (progress) {
2328 progress = false;
2329 for (int i = C->macro_count(); i > 0; i--) {
2330 Node * n = C->macro_node(i-1);
2331 bool success = false;
2332 debug_only(int old_macro_count = C->macro_count(););
2333 if (n->Opcode() == Op_LoopLimit) {
2334 // Remove it from macro list and put on IGVN worklist to optimize.
2335 C->remove_macro_node(n);
2336 _igvn._worklist.push(n);
2337 success = true;
2338 } else if (n->Opcode() == Op_Opaque1 || n->Opcode() == Op_Opaque2) {
2339 _igvn.replace_node(n, n->in(1));
2340 success = true;
2341 }
2342 assert(success == (C->macro_count() < old_macro_count), "elimination reduces macro count");
2343 progress = progress || success;
2344 }
2345 }
2346
2347 // expand "macro" nodes
2348 // nodes are removed from the macro list as they are processed
2349 while (C->macro_count() > 0) {
2350 int macro_count = C->macro_count();
2351 Node * n = C->macro_node(macro_count-1);
2352 assert(n->is_macro(), "only macro nodes expected here");
2353 if (_igvn.type(n) == Type::TOP || n->in(0)->is_top() ) {
2354 // node is unreachable, so don't try to expand it
2355 C->remove_macro_node(n);
2356 continue;
2357 }
2358 switch (n->class_id()) {
2359 case Node::Class_Allocate:
2360 expand_allocate(n->as_Allocate());
2361 break;
2362 case Node::Class_AllocateArray:
2363 expand_allocate_array(n->as_AllocateArray());
2364 break;
2365 case Node::Class_Lock:
2366 expand_lock_node(n->as_Lock());
2367 break;
2368 case Node::Class_Unlock:
2369 expand_unlock_node(n->as_Unlock());
2370 break;
2371 default:
2372 assert(false, "unknown node type in macro list");
2373 }
2374 assert(C->macro_count() < macro_count, "must have deleted a node from macro list");
2375 if (C->failing()) return true;
2376 }
2377
2378 _igvn.set_delay_transform(false);
2379 _igvn.optimize();
2380 if (C->failing()) return true;
2381 return false;
2382 }