1 /*
2 * Copyright (c) 2005, 2016, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "compiler/compileLog.hpp"
27 #include "gc/shenandoah/brooksPointer.hpp"
28 #include "libadt/vectset.hpp"
29 #include "opto/addnode.hpp"
30 #include "opto/arraycopynode.hpp"
31 #include "opto/callnode.hpp"
32 #include "opto/castnode.hpp"
33 #include "opto/cfgnode.hpp"
34 #include "opto/compile.hpp"
35 #include "opto/convertnode.hpp"
36 #include "opto/graphKit.hpp"
37 #include "opto/locknode.hpp"
38 #include "opto/loopnode.hpp"
39 #include "opto/macro.hpp"
40 #include "opto/memnode.hpp"
41 #include "opto/narrowptrnode.hpp"
42 #include "opto/node.hpp"
43 #include "opto/opaquenode.hpp"
44 #include "opto/phaseX.hpp"
45 #include "opto/rootnode.hpp"
46 #include "opto/runtime.hpp"
47 #include "opto/shenandoahSupport.hpp"
48 #include "opto/subnode.hpp"
49 #include "opto/type.hpp"
50 #include "runtime/sharedRuntime.hpp"
51
52
53 //
54 // Replace any references to "oldref" in inputs to "use" with "newref".
55 // Returns the number of replacements made.
56 //
57 int PhaseMacroExpand::replace_input(Node *use, Node *oldref, Node *newref) {
58 int nreplacements = 0;
59 uint req = use->req();
60 for (uint j = 0; j < use->len(); j++) {
61 Node *uin = use->in(j);
62 if (uin == oldref) {
63 if (j < req)
64 use->set_req(j, newref);
65 else
66 use->set_prec(j, newref);
67 nreplacements++;
68 } else if (j >= req && uin == NULL) {
69 break;
70 }
71 }
72 return nreplacements;
73 }
74
75 void PhaseMacroExpand::copy_call_debug_info(CallNode *oldcall, CallNode * newcall) {
76 // Copy debug information and adjust JVMState information
77 uint old_dbg_start = oldcall->tf()->domain()->cnt();
78 uint new_dbg_start = newcall->tf()->domain()->cnt();
79 int jvms_adj = new_dbg_start - old_dbg_start;
80 assert (new_dbg_start == newcall->req(), "argument count mismatch");
81
82 // SafePointScalarObject node could be referenced several times in debug info.
83 // Use Dict to record cloned nodes.
84 Dict* sosn_map = new Dict(cmpkey,hashkey);
85 for (uint i = old_dbg_start; i < oldcall->req(); i++) {
86 Node* old_in = oldcall->in(i);
87 // Clone old SafePointScalarObjectNodes, adjusting their field contents.
88 if (old_in != NULL && old_in->is_SafePointScalarObject()) {
89 SafePointScalarObjectNode* old_sosn = old_in->as_SafePointScalarObject();
90 uint old_unique = C->unique();
91 Node* new_in = old_sosn->clone(sosn_map);
92 if (old_unique != C->unique()) { // New node?
93 new_in->set_req(0, C->root()); // reset control edge
94 new_in = transform_later(new_in); // Register new node.
95 }
96 old_in = new_in;
97 }
98 newcall->add_req(old_in);
99 }
100
101 // JVMS may be shared so clone it before we modify it
102 newcall->set_jvms(oldcall->jvms() != NULL ? oldcall->jvms()->clone_deep(C) : NULL);
103 for (JVMState *jvms = newcall->jvms(); jvms != NULL; jvms = jvms->caller()) {
104 jvms->set_map(newcall);
105 jvms->set_locoff(jvms->locoff()+jvms_adj);
106 jvms->set_stkoff(jvms->stkoff()+jvms_adj);
107 jvms->set_monoff(jvms->monoff()+jvms_adj);
108 jvms->set_scloff(jvms->scloff()+jvms_adj);
109 jvms->set_endoff(jvms->endoff()+jvms_adj);
110 }
111 }
112
113 Node* PhaseMacroExpand::opt_bits_test(Node* ctrl, Node* region, int edge, Node* word, int mask, int bits, bool return_fast_path) {
114 Node* cmp;
115 if (mask != 0) {
116 Node* and_node = transform_later(new AndXNode(word, MakeConX(mask)));
117 cmp = transform_later(new CmpXNode(and_node, MakeConX(bits)));
118 } else {
119 cmp = word;
120 }
121 Node* bol = transform_later(new BoolNode(cmp, BoolTest::ne));
122 IfNode* iff = new IfNode( ctrl, bol, PROB_MIN, COUNT_UNKNOWN );
123 transform_later(iff);
124
125 // Fast path taken.
126 Node *fast_taken = transform_later(new IfFalseNode(iff));
127
128 // Fast path not-taken, i.e. slow path
129 Node *slow_taken = transform_later(new IfTrueNode(iff));
130
131 if (return_fast_path) {
132 region->init_req(edge, slow_taken); // Capture slow-control
133 return fast_taken;
134 } else {
135 region->init_req(edge, fast_taken); // Capture fast-control
136 return slow_taken;
137 }
138 }
139
140 //--------------------copy_predefined_input_for_runtime_call--------------------
141 void PhaseMacroExpand::copy_predefined_input_for_runtime_call(Node * ctrl, CallNode* oldcall, CallNode* call) {
142 // Set fixed predefined input arguments
143 call->init_req( TypeFunc::Control, ctrl );
144 call->init_req( TypeFunc::I_O , oldcall->in( TypeFunc::I_O) );
145 call->init_req( TypeFunc::Memory , oldcall->in( TypeFunc::Memory ) ); // ?????
146 call->init_req( TypeFunc::ReturnAdr, oldcall->in( TypeFunc::ReturnAdr ) );
147 call->init_req( TypeFunc::FramePtr, oldcall->in( TypeFunc::FramePtr ) );
148 }
149
150 //------------------------------make_slow_call---------------------------------
151 CallNode* PhaseMacroExpand::make_slow_call(CallNode *oldcall, const TypeFunc* slow_call_type,
152 address slow_call, const char* leaf_name, Node* slow_path,
153 Node* parm0, Node* parm1, Node* parm2) {
154
155 // Slow-path call
156 CallNode *call = leaf_name
157 ? (CallNode*)new CallLeafNode ( slow_call_type, slow_call, leaf_name, TypeRawPtr::BOTTOM )
158 : (CallNode*)new CallStaticJavaNode( slow_call_type, slow_call, OptoRuntime::stub_name(slow_call), oldcall->jvms()->bci(), TypeRawPtr::BOTTOM );
159
160 // Slow path call has no side-effects, uses few values
161 copy_predefined_input_for_runtime_call(slow_path, oldcall, call );
162 if (parm0 != NULL) call->init_req(TypeFunc::Parms+0, parm0);
163 if (parm1 != NULL) call->init_req(TypeFunc::Parms+1, parm1);
164 if (parm2 != NULL) call->init_req(TypeFunc::Parms+2, parm2);
165 copy_call_debug_info(oldcall, call);
166 call->set_cnt(PROB_UNLIKELY_MAG(4)); // Same effect as RC_UNCOMMON.
167 _igvn.replace_node(oldcall, call);
168 transform_later(call);
169
170 return call;
171 }
172
173 void PhaseMacroExpand::extract_call_projections(CallNode *call) {
174 _fallthroughproj = NULL;
175 _fallthroughcatchproj = NULL;
176 _ioproj_fallthrough = NULL;
177 _ioproj_catchall = NULL;
178 _catchallcatchproj = NULL;
179 _memproj_fallthrough = NULL;
180 _memproj_catchall = NULL;
181 _resproj = NULL;
182 for (DUIterator_Fast imax, i = call->fast_outs(imax); i < imax; i++) {
183 ProjNode *pn = call->fast_out(i)->as_Proj();
184 switch (pn->_con) {
185 case TypeFunc::Control:
186 {
187 // For Control (fallthrough) and I_O (catch_all_index) we have CatchProj -> Catch -> Proj
188 _fallthroughproj = pn;
189 DUIterator_Fast jmax, j = pn->fast_outs(jmax);
190 const Node *cn = pn->fast_out(j);
191 if (cn->is_Catch()) {
192 ProjNode *cpn = NULL;
193 for (DUIterator_Fast kmax, k = cn->fast_outs(kmax); k < kmax; k++) {
194 cpn = cn->fast_out(k)->as_Proj();
195 assert(cpn->is_CatchProj(), "must be a CatchProjNode");
196 if (cpn->_con == CatchProjNode::fall_through_index)
197 _fallthroughcatchproj = cpn;
198 else {
199 assert(cpn->_con == CatchProjNode::catch_all_index, "must be correct index.");
200 _catchallcatchproj = cpn;
201 }
202 }
203 }
204 break;
205 }
206 case TypeFunc::I_O:
207 if (pn->_is_io_use)
208 _ioproj_catchall = pn;
209 else
210 _ioproj_fallthrough = pn;
211 break;
212 case TypeFunc::Memory:
213 if (pn->_is_io_use)
214 _memproj_catchall = pn;
215 else
216 _memproj_fallthrough = pn;
217 break;
218 case TypeFunc::Parms:
219 _resproj = pn;
220 break;
221 default:
222 assert(false, "unexpected projection from allocation node.");
223 }
224 }
225
226 }
227
228 // Eliminate a card mark sequence. p2x is a ConvP2XNode
229 void PhaseMacroExpand::eliminate_card_mark(Node* p2x) {
230 assert(p2x->Opcode() == Op_CastP2X, "ConvP2XNode required");
231 if (!UseG1GC) {
232 // vanilla/CMS post barrier
233 Node *shift = p2x->unique_out();
234 Node *addp = shift->unique_out();
235 for (DUIterator_Last jmin, j = addp->last_outs(jmin); j >= jmin; --j) {
236 Node *mem = addp->last_out(j);
237 if (UseCondCardMark && mem->is_Load()) {
238 assert(mem->Opcode() == Op_LoadB, "unexpected code shape");
239 // The load is checking if the card has been written so
240 // replace it with zero to fold the test.
241 _igvn.replace_node(mem, intcon(0));
242 continue;
243 }
244 assert(mem->is_Store(), "store required");
245 _igvn.replace_node(mem, mem->in(MemNode::Memory));
246 }
247 } else {
248 // G1 pre/post barriers
249 assert(p2x->outcnt() <= 2, "expects 1 or 2 users: Xor and URShift nodes");
250 // It could be only one user, URShift node, in Object.clone() intrinsic
251 // but the new allocation is passed to arraycopy stub and it could not
252 // be scalar replaced. So we don't check the case.
253
254 // An other case of only one user (Xor) is when the value check for NULL
255 // in G1 post barrier is folded after CCP so the code which used URShift
256 // is removed.
257
258 // Take Region node before eliminating post barrier since it also
259 // eliminates CastP2X node when it has only one user.
260 Node* this_region = p2x->in(0);
261 assert(this_region != NULL, "");
262
263 // Remove G1 post barrier.
264
265 // Search for CastP2X->Xor->URShift->Cmp path which
266 // checks if the store done to a different from the value's region.
267 // And replace Cmp with #0 (false) to collapse G1 post barrier.
268 Node* xorx = p2x->find_out_with(Op_XorX);
269 if (xorx != NULL) {
270 Node* shift = xorx->unique_out();
271 Node* cmpx = shift->unique_out();
272 assert(cmpx->is_Cmp() && cmpx->unique_out()->is_Bool() &&
273 cmpx->unique_out()->as_Bool()->_test._test == BoolTest::ne,
274 "missing region check in G1 post barrier");
275 _igvn.replace_node(cmpx, makecon(TypeInt::CC_EQ));
276
277 // Remove G1 pre barrier.
278
279 // Search "if (marking != 0)" check and set it to "false".
280 // There is no G1 pre barrier if previous stored value is NULL
281 // (for example, after initialization).
282 if (this_region->is_Region() && this_region->req() == 3) {
283 int ind = 1;
284 if (!this_region->in(ind)->is_IfFalse()) {
285 ind = 2;
286 }
287 if (this_region->in(ind)->is_IfFalse() &&
288 this_region->in(ind)->in(0)->is_g1_marking_if(&_igvn)) {
289 Node* cmpx = this_region->in(ind)->in(0)->in(1)->in(1);
290 _igvn.replace_node(cmpx, makecon(TypeInt::CC_EQ));
291 }
292 }
293 } else {
294 assert(!GraphKit::use_ReduceInitialCardMarks(), "can only happen with card marking");
295 // This is a G1 post barrier emitted by the Object.clone() intrinsic.
296 // Search for the CastP2X->URShiftX->AddP->LoadB->Cmp path which checks if the card
297 // is marked as young_gen and replace the Cmp with 0 (false) to collapse the barrier.
298 Node* shift = p2x->find_out_with(Op_URShiftX);
299 assert(shift != NULL, "missing G1 post barrier");
300 Node* addp = shift->unique_out();
301 Node* load = addp->find_out_with(Op_LoadB);
302 assert(load != NULL, "missing G1 post barrier");
303 Node* cmpx = load->unique_out();
304 assert(cmpx->is_Cmp() && cmpx->unique_out()->is_Bool() &&
305 cmpx->unique_out()->as_Bool()->_test._test == BoolTest::ne,
306 "missing card value check in G1 post barrier");
307 _igvn.replace_node(cmpx, makecon(TypeInt::CC_EQ));
308 // There is no G1 pre barrier in this case
309 }
310 // Now CastP2X can be removed since it is used only on dead path
311 // which currently still alive until igvn optimize it.
312 assert(p2x->outcnt() == 0 || p2x->unique_out()->Opcode() == Op_URShiftX, "");
313 _igvn.replace_node(p2x, top());
314 }
315 }
316
317 void PhaseMacroExpand::eliminate_g1_wb_pre(Node* n) {
318 Node* c = n->as_Call()->proj_out(TypeFunc::Control);
319 c = c->unique_ctrl_out();
320 assert(c->is_Region() && c->req() == 3, "where's the pre barrier control flow?");
321 c = c->unique_ctrl_out();
322 assert(c->is_Region() && c->req() == 3, "where's the pre barrier control flow?");
323 Node* iff = c->in(1)->is_IfProj() ? c->in(1)->in(0) : c->in(2)->in(0);
324 assert(iff->is_If(), "expect test");
325 if (!iff->is_g1_marking_if(&_igvn)) {
326 c = c->unique_ctrl_out();
327 assert(c->is_Region() && c->req() == 3, "where's the pre barrier control flow?");
328 iff = c->in(1)->is_IfProj() ? c->in(1)->in(0) : c->in(2)->in(0);
329 assert(iff->is_g1_marking_if(&_igvn), "expect marking test");
330 }
331 Node* cmpx = iff->in(1)->in(1);
332 _igvn.replace_node(cmpx, makecon(TypeInt::CC_EQ));
333 _igvn.rehash_node_delayed(n);
334 n->del_req(n->req()-1);
335 }
336
337 // Search for a memory operation for the specified memory slice.
338 static Node *scan_mem_chain(Node *mem, int alias_idx, int offset, Node *start_mem, Node *alloc, PhaseGVN *phase) {
339 Node *orig_mem = mem;
340 Node *alloc_mem = alloc->in(TypeFunc::Memory);
341 const TypeOopPtr *tinst = phase->C->get_adr_type(alias_idx)->isa_oopptr();
342 while (true) {
343 if (mem == alloc_mem || mem == start_mem ) {
344 return mem; // hit one of our sentinels
345 } else if (mem->is_MergeMem()) {
346 mem = mem->as_MergeMem()->memory_at(alias_idx);
347 } else if (mem->is_Proj() && mem->as_Proj()->_con == TypeFunc::Memory) {
348 Node *in = mem->in(0);
349 // we can safely skip over safepoints, calls, locks and membars because we
350 // already know that the object is safe to eliminate.
351 if (in->is_Initialize() && in->as_Initialize()->allocation() == alloc) {
352 return in;
353 } else if (in->is_Call()) {
354 CallNode *call = in->as_Call();
355 if (call->may_modify(tinst, phase)) {
356 assert(call->is_ArrayCopy(), "ArrayCopy is the only call node that doesn't make allocation escape");
357 if (call->as_ArrayCopy()->modifies(offset, offset, phase, false)) {
358 return in;
359 }
360 }
361 mem = in->in(TypeFunc::Memory);
362 } else if (in->is_MemBar()) {
363 ArrayCopyNode* ac = NULL;
364 if (ArrayCopyNode::may_modify(tinst, in->as_MemBar(), phase, ac)) {
365 assert(ac != NULL && ac->is_clonebasic(), "Only basic clone is a non escaping clone");
366 return ac;
367 }
368 mem = in->in(TypeFunc::Memory);
369 } else {
370 assert(false, "unexpected projection");
371 }
372 } else if (mem->is_Store()) {
373 const TypePtr* atype = mem->as_Store()->adr_type();
374 int adr_idx = phase->C->get_alias_index(atype);
375 if (adr_idx == alias_idx) {
376 assert(atype->isa_oopptr(), "address type must be oopptr");
377 int adr_offset = atype->offset();
378 uint adr_iid = atype->is_oopptr()->instance_id();
379 // Array elements references have the same alias_idx
380 // but different offset and different instance_id.
381 if (adr_offset == offset && adr_iid == alloc->_idx)
382 return mem;
383 } else {
384 assert(adr_idx == Compile::AliasIdxRaw, "address must match or be raw");
385 }
386 mem = mem->in(MemNode::Memory);
387 } else if (mem->is_ClearArray()) {
388 if (!ClearArrayNode::step_through(&mem, alloc->_idx, phase)) {
389 // Can not bypass initialization of the instance
390 // we are looking.
391 debug_only(intptr_t offset;)
392 assert(alloc == AllocateNode::Ideal_allocation(mem->in(3), phase, offset), "sanity");
393 InitializeNode* init = alloc->as_Allocate()->initialization();
394 // We are looking for stored value, return Initialize node
395 // or memory edge from Allocate node.
396 if (init != NULL)
397 return init;
398 else
399 return alloc->in(TypeFunc::Memory); // It will produce zero value (see callers).
400 }
401 // Otherwise skip it (the call updated 'mem' value).
402 } else if (mem->Opcode() == Op_SCMemProj) {
403 mem = mem->in(0);
404 Node* adr = NULL;
405 if (mem->is_LoadStore()) {
406 adr = mem->in(MemNode::Address);
407 } else {
408 assert(mem->Opcode() == Op_EncodeISOArray ||
409 mem->Opcode() == Op_StrCompressedCopy, "sanity");
410 adr = mem->in(3); // Destination array
411 }
412 const TypePtr* atype = adr->bottom_type()->is_ptr();
413 int adr_idx = phase->C->get_alias_index(atype);
414 if (adr_idx == alias_idx) {
415 DEBUG_ONLY(mem->dump();)
416 assert(false, "Object is not scalar replaceable if a LoadStore node accesses its field");
417 return NULL;
418 }
419 mem = mem->in(MemNode::Memory);
420 } else if (mem->Opcode() == Op_StrInflatedCopy) {
421 Node* adr = mem->in(3); // Destination array
422 const TypePtr* atype = adr->bottom_type()->is_ptr();
423 int adr_idx = phase->C->get_alias_index(atype);
424 if (adr_idx == alias_idx) {
425 DEBUG_ONLY(mem->dump();)
426 assert(false, "Object is not scalar replaceable if a StrInflatedCopy node accesses its field");
427 return NULL;
428 }
429 mem = mem->in(MemNode::Memory);
430 } else {
431 return mem;
432 }
433 assert(mem != orig_mem, "dead memory loop");
434 }
435 }
436
437 // Generate loads from source of the arraycopy for fields of
438 // destination needed at a deoptimization point
439 Node* PhaseMacroExpand::make_arraycopy_load(ArrayCopyNode* ac, intptr_t offset, Node* ctl, Node* mem, BasicType ft, const Type *ftype, AllocateNode *alloc) {
440 BasicType bt = ft;
441 const Type *type = ftype;
442 if (ft == T_NARROWOOP) {
443 bt = T_OBJECT;
444 type = ftype->make_oopptr();
445 }
446 Node* res = NULL;
447 if (ac->is_clonebasic()) {
448 Node* base = ac->in(ArrayCopyNode::Src)->in(AddPNode::Base);
449 Node* adr = _igvn.transform(new AddPNode(base, base, MakeConX(offset)));
450 const TypePtr* adr_type = _igvn.type(base)->is_ptr()->add_offset(offset);
451 res = LoadNode::make(_igvn, ctl, mem, adr, adr_type, type, bt, MemNode::unordered, LoadNode::Pinned);
452 } else {
453 if (ac->modifies(offset, offset, &_igvn, true)) {
454 assert(ac->in(ArrayCopyNode::Dest) == alloc->result_cast(), "arraycopy destination should be allocation's result");
455 uint shift = exact_log2(type2aelembytes(bt));
456 Node* diff = _igvn.transform(new SubINode(ac->in(ArrayCopyNode::SrcPos), ac->in(ArrayCopyNode::DestPos)));
457 #ifdef _LP64
458 diff = _igvn.transform(new ConvI2LNode(diff));
459 #endif
460 diff = _igvn.transform(new LShiftXNode(diff, intcon(shift)));
461
462 Node* off = _igvn.transform(new AddXNode(MakeConX(offset), diff));
463 Node* base = ac->in(ArrayCopyNode::Src);
464 Node* adr = _igvn.transform(new AddPNode(base, base, off));
465 const TypePtr* adr_type = _igvn.type(base)->is_ptr()->add_offset(offset);
466 res = LoadNode::make(_igvn, ctl, mem, adr, adr_type, type, bt, MemNode::unordered, LoadNode::Pinned);
467 }
468 }
469 if (res != NULL) {
470 res = _igvn.transform(res);
471 if (ftype->isa_narrowoop()) {
472 // PhaseMacroExpand::scalar_replacement adds DecodeN nodes
473 res = _igvn.transform(new EncodePNode(res, ftype));
474 }
475 return res;
476 }
477 return NULL;
478 }
479
480 //
481 // Given a Memory Phi, compute a value Phi containing the values from stores
482 // on the input paths.
483 // Note: this function is recursive, its depth is limited by the "level" argument
484 // Returns the computed Phi, or NULL if it cannot compute it.
485 Node *PhaseMacroExpand::value_from_mem_phi(Node *mem, BasicType ft, const Type *phi_type, const TypeOopPtr *adr_t, AllocateNode *alloc, Node_Stack *value_phis, int level) {
486 assert(mem->is_Phi(), "sanity");
487 int alias_idx = C->get_alias_index(adr_t);
488 int offset = adr_t->offset();
489 int instance_id = adr_t->instance_id();
490
491 // Check if an appropriate value phi already exists.
492 Node* region = mem->in(0);
493 for (DUIterator_Fast kmax, k = region->fast_outs(kmax); k < kmax; k++) {
494 Node* phi = region->fast_out(k);
495 if (phi->is_Phi() && phi != mem &&
496 phi->as_Phi()->is_same_inst_field(phi_type, (int)mem->_idx, instance_id, alias_idx, offset)) {
497 return phi;
498 }
499 }
500 // Check if an appropriate new value phi already exists.
501 Node* new_phi = value_phis->find(mem->_idx);
502 if (new_phi != NULL)
503 return new_phi;
504
505 if (level <= 0) {
506 return NULL; // Give up: phi tree too deep
507 }
508 Node *start_mem = C->start()->proj_out(TypeFunc::Memory);
509 Node *alloc_mem = alloc->in(TypeFunc::Memory);
510
511 uint length = mem->req();
512 GrowableArray <Node *> values(length, length, NULL, false);
513
514 // create a new Phi for the value
515 PhiNode *phi = new PhiNode(mem->in(0), phi_type, NULL, mem->_idx, instance_id, alias_idx, offset);
516 transform_later(phi);
517 value_phis->push(phi, mem->_idx);
518
519 for (uint j = 1; j < length; j++) {
520 Node *in = mem->in(j);
521 if (in == NULL || in->is_top()) {
522 values.at_put(j, in);
523 } else {
524 Node *val = scan_mem_chain(in, alias_idx, offset, start_mem, alloc, &_igvn);
525 if (val == start_mem || val == alloc_mem) {
526 // hit a sentinel, return appropriate 0 value
527 values.at_put(j, _igvn.zerocon(ft));
528 continue;
529 }
530 if (val->is_Initialize()) {
531 val = val->as_Initialize()->find_captured_store(offset, type2aelembytes(ft), &_igvn);
532 }
533 if (val == NULL) {
534 return NULL; // can't find a value on this path
535 }
536 if (val == mem) {
537 values.at_put(j, mem);
538 } else if (val->is_Store()) {
539 values.at_put(j, ShenandoahBarrierNode::skip_through_barrier(val->in(MemNode::ValueIn)));
540 } else if(val->is_Proj() && val->in(0) == alloc) {
541 values.at_put(j, _igvn.zerocon(ft));
542 } else if (val->is_Phi()) {
543 val = value_from_mem_phi(val, ft, phi_type, adr_t, alloc, value_phis, level-1);
544 if (val == NULL) {
545 return NULL;
546 }
547 values.at_put(j, val);
548 } else if (val->Opcode() == Op_SCMemProj) {
549 assert(val->in(0)->is_LoadStore() ||
550 val->in(0)->Opcode() == Op_EncodeISOArray ||
551 val->in(0)->Opcode() == Op_StrCompressedCopy, "sanity");
552 assert(false, "Object is not scalar replaceable if a LoadStore node accesses its field");
553 return NULL;
554 } else if (val->is_ArrayCopy()) {
555 Node* res = make_arraycopy_load(val->as_ArrayCopy(), offset, val->in(0), val->in(TypeFunc::Memory), ft, phi_type, alloc);
556 if (res == NULL) {
557 return NULL;
558 }
559 values.at_put(j, res);
560 } else {
561 #ifdef ASSERT
562 val->dump();
563 assert(false, "unknown node on this path");
564 #endif
565 return NULL; // unknown node on this path
566 }
567 }
568 }
569 // Set Phi's inputs
570 for (uint j = 1; j < length; j++) {
571 if (values.at(j) == mem) {
572 phi->init_req(j, phi);
573 } else {
574 phi->init_req(j, values.at(j));
575 }
576 }
577 return phi;
578 }
579
580 // Search the last value stored into the object's field.
581 Node *PhaseMacroExpand::value_from_mem(Node *sfpt_mem, Node *sfpt_ctl, BasicType ft, const Type *ftype, const TypeOopPtr *adr_t, AllocateNode *alloc) {
582 assert(adr_t->is_known_instance_field(), "instance required");
583 int instance_id = adr_t->instance_id();
584 assert((uint)instance_id == alloc->_idx, "wrong allocation");
585
586 int alias_idx = C->get_alias_index(adr_t);
587 int offset = adr_t->offset();
588 Node *start_mem = C->start()->proj_out(TypeFunc::Memory);
589 Node *alloc_ctrl = alloc->in(TypeFunc::Control);
590 Node *alloc_mem = alloc->in(TypeFunc::Memory);
591 Arena *a = Thread::current()->resource_area();
592 VectorSet visited(a);
593
594
595 bool done = sfpt_mem == alloc_mem;
596 Node *mem = sfpt_mem;
597 while (!done) {
598 if (visited.test_set(mem->_idx)) {
599 return NULL; // found a loop, give up
600 }
601 mem = scan_mem_chain(mem, alias_idx, offset, start_mem, alloc, &_igvn);
602 if (mem == start_mem || mem == alloc_mem) {
603 done = true; // hit a sentinel, return appropriate 0 value
604 } else if (mem->is_Initialize()) {
605 mem = mem->as_Initialize()->find_captured_store(offset, type2aelembytes(ft), &_igvn);
606 if (mem == NULL) {
607 done = true; // Something go wrong.
608 } else if (mem->is_Store()) {
609 const TypePtr* atype = mem->as_Store()->adr_type();
610 assert(C->get_alias_index(atype) == Compile::AliasIdxRaw, "store is correct memory slice");
611 done = true;
612 }
613 } else if (mem->is_Store()) {
614 const TypeOopPtr* atype = mem->as_Store()->adr_type()->isa_oopptr();
615 assert(atype != NULL, "address type must be oopptr");
616 assert(C->get_alias_index(atype) == alias_idx &&
617 atype->is_known_instance_field() && atype->offset() == offset &&
618 atype->instance_id() == instance_id, "store is correct memory slice");
619 done = true;
620 } else if (mem->is_Phi()) {
621 // try to find a phi's unique input
622 Node *unique_input = NULL;
623 Node *top = C->top();
624 for (uint i = 1; i < mem->req(); i++) {
625 Node *n = scan_mem_chain(mem->in(i), alias_idx, offset, start_mem, alloc, &_igvn);
626 if (n == NULL || n == top || n == mem) {
627 continue;
628 } else if (unique_input == NULL) {
629 unique_input = n;
630 } else if (unique_input != n) {
631 unique_input = top;
632 break;
633 }
634 }
635 if (unique_input != NULL && unique_input != top) {
636 mem = unique_input;
637 } else {
638 done = true;
639 }
640 } else if (mem->is_ArrayCopy()) {
641 done = true;
642 } else {
643 assert(false, "unexpected node");
644 }
645 }
646 if (mem != NULL) {
647 if (mem == start_mem || mem == alloc_mem) {
648 // hit a sentinel, return appropriate 0 value
649 return _igvn.zerocon(ft);
650 } else if (mem->is_Store()) {
651 return ShenandoahBarrierNode::skip_through_barrier(mem->in(MemNode::ValueIn));
652 } else if (mem->is_Phi()) {
653 // attempt to produce a Phi reflecting the values on the input paths of the Phi
654 Node_Stack value_phis(a, 8);
655 Node * phi = value_from_mem_phi(mem, ft, ftype, adr_t, alloc, &value_phis, ValueSearchLimit);
656 if (phi != NULL) {
657 return phi;
658 } else {
659 // Kill all new Phis
660 while(value_phis.is_nonempty()) {
661 Node* n = value_phis.node();
662 _igvn.replace_node(n, C->top());
663 value_phis.pop();
664 }
665 }
666 } else if (mem->is_ArrayCopy()) {
667 Node* ctl = mem->in(0);
668 Node* m = mem->in(TypeFunc::Memory);
669 if (sfpt_ctl->is_Proj() && sfpt_ctl->as_Proj()->is_uncommon_trap_proj(Deoptimization::Reason_none)) {
670 // pin the loads in the uncommon trap path
671 ctl = sfpt_ctl;
672 m = sfpt_mem;
673 }
674 return make_arraycopy_load(mem->as_ArrayCopy(), offset, ctl, m, ft, ftype, alloc);
675 }
676 }
677 // Something go wrong.
678 return NULL;
679 }
680
681 // Check the possibility of scalar replacement.
682 bool PhaseMacroExpand::can_eliminate_allocation(AllocateNode *alloc, GrowableArray <SafePointNode *>& safepoints) {
683 // Scan the uses of the allocation to check for anything that would
684 // prevent us from eliminating it.
685 NOT_PRODUCT( const char* fail_eliminate = NULL; )
686 DEBUG_ONLY( Node* disq_node = NULL; )
687 bool can_eliminate = true;
688
689 Node* res = alloc->result_cast();
690 const TypeOopPtr* res_type = NULL;
691 if (res == NULL) {
692 // All users were eliminated.
693 } else if (!res->is_CheckCastPP()) {
694 NOT_PRODUCT(fail_eliminate = "Allocation does not have unique CheckCastPP";)
695 can_eliminate = false;
696 } else {
697 res_type = _igvn.type(res)->isa_oopptr();
698 if (res_type == NULL) {
699 NOT_PRODUCT(fail_eliminate = "Neither instance or array allocation";)
700 can_eliminate = false;
701 } else if (res_type->isa_aryptr()) {
702 int length = alloc->in(AllocateNode::ALength)->find_int_con(-1);
703 if (length < 0) {
704 NOT_PRODUCT(fail_eliminate = "Array's size is not constant";)
705 can_eliminate = false;
706 }
707 }
708 }
709
710 if (can_eliminate && res != NULL) {
711 for (DUIterator_Fast jmax, j = res->fast_outs(jmax);
712 j < jmax && can_eliminate; j++) {
713 Node* use = res->fast_out(j);
714
715 if (use->is_AddP()) {
716 const TypePtr* addp_type = _igvn.type(use)->is_ptr();
717 int offset = addp_type->offset();
718
719 if (offset == Type::OffsetTop || offset == Type::OffsetBot) {
720 NOT_PRODUCT(fail_eliminate = "Undefined field referrence";)
721 can_eliminate = false;
722 break;
723 }
724 for (DUIterator_Fast kmax, k = use->fast_outs(kmax);
725 k < kmax && can_eliminate; k++) {
726 Node* n = use->fast_out(k);
727 if (!n->is_Store() && n->Opcode() != Op_CastP2X &&
728 !n->is_g1_wb_pre_call() &&
729 !(n->is_ArrayCopy() &&
730 n->as_ArrayCopy()->is_clonebasic() &&
731 n->in(ArrayCopyNode::Dest) == use)) {
732 DEBUG_ONLY(disq_node = n;)
733 if (n->is_Load() || n->is_LoadStore()) {
734 NOT_PRODUCT(fail_eliminate = "Field load";)
735 } else {
736 NOT_PRODUCT(fail_eliminate = "Not store field referrence";)
737 }
738 can_eliminate = false;
739 }
740 }
741 } else if (use->is_ArrayCopy() &&
742 (use->as_ArrayCopy()->is_arraycopy_validated() ||
743 use->as_ArrayCopy()->is_copyof_validated() ||
744 use->as_ArrayCopy()->is_copyofrange_validated()) &&
745 use->in(ArrayCopyNode::Dest) == res) {
746 // ok to eliminate
747 } else if (use->is_SafePoint()) {
748 SafePointNode* sfpt = use->as_SafePoint();
749 if (sfpt->is_Call() && sfpt->as_Call()->has_non_debug_use(res)) {
750 // Object is passed as argument.
751 DEBUG_ONLY(disq_node = use;)
752 NOT_PRODUCT(fail_eliminate = "Object is passed as argument";)
753 can_eliminate = false;
754 }
755 Node* sfptMem = sfpt->memory();
756 if (sfptMem == NULL || sfptMem->is_top()) {
757 DEBUG_ONLY(disq_node = use;)
758 NOT_PRODUCT(fail_eliminate = "NULL or TOP memory";)
759 can_eliminate = false;
760 } else {
761 safepoints.append_if_missing(sfpt);
762 }
763 } else if (use->Opcode() != Op_CastP2X) { // CastP2X is used by card mark
764 if (use->is_Phi()) {
765 if (use->outcnt() == 1 && use->unique_out()->Opcode() == Op_Return) {
766 NOT_PRODUCT(fail_eliminate = "Object is return value";)
767 } else {
768 NOT_PRODUCT(fail_eliminate = "Object is referenced by Phi";)
769 }
770 DEBUG_ONLY(disq_node = use;)
771 } else {
772 if (use->Opcode() == Op_Return) {
773 NOT_PRODUCT(fail_eliminate = "Object is return value";)
774 }else {
775 NOT_PRODUCT(fail_eliminate = "Object is referenced by node";)
776 }
777 DEBUG_ONLY(disq_node = use;)
778 }
779 can_eliminate = false;
780 }
781 }
782 }
783
784 #ifndef PRODUCT
785 if (PrintEliminateAllocations) {
786 if (can_eliminate) {
787 tty->print("Scalar ");
788 if (res == NULL)
789 alloc->dump();
790 else
791 res->dump();
792 } else if (alloc->_is_scalar_replaceable) {
793 tty->print("NotScalar (%s)", fail_eliminate);
794 if (res == NULL)
795 alloc->dump();
796 else
797 res->dump();
798 #ifdef ASSERT
799 if (disq_node != NULL) {
800 tty->print(" >>>> ");
801 disq_node->dump();
802 }
803 #endif /*ASSERT*/
804 }
805 }
806 #endif
807 return can_eliminate;
808 }
809
810 // Do scalar replacement.
811 bool PhaseMacroExpand::scalar_replacement(AllocateNode *alloc, GrowableArray <SafePointNode *>& safepoints) {
812 GrowableArray <SafePointNode *> safepoints_done;
813
814 ciKlass* klass = NULL;
815 ciInstanceKlass* iklass = NULL;
816 int nfields = 0;
817 int array_base = 0;
818 int element_size = 0;
819 BasicType basic_elem_type = T_ILLEGAL;
820 ciType* elem_type = NULL;
821
822 Node* res = alloc->result_cast();
823 assert(res == NULL || res->is_CheckCastPP(), "unexpected AllocateNode result");
824 const TypeOopPtr* res_type = NULL;
825 if (res != NULL) { // Could be NULL when there are no users
826 res_type = _igvn.type(res)->isa_oopptr();
827 }
828
829 if (res != NULL) {
830 klass = res_type->klass();
831 if (res_type->isa_instptr()) {
832 // find the fields of the class which will be needed for safepoint debug information
833 assert(klass->is_instance_klass(), "must be an instance klass.");
834 iklass = klass->as_instance_klass();
835 nfields = iklass->nof_nonstatic_fields();
836 } else {
837 // find the array's elements which will be needed for safepoint debug information
838 nfields = alloc->in(AllocateNode::ALength)->find_int_con(-1);
839 assert(klass->is_array_klass() && nfields >= 0, "must be an array klass.");
840 elem_type = klass->as_array_klass()->element_type();
841 basic_elem_type = elem_type->basic_type();
842 array_base = arrayOopDesc::base_offset_in_bytes(basic_elem_type);
843 element_size = type2aelembytes(basic_elem_type);
844 }
845 }
846 //
847 // Process the safepoint uses
848 //
849 while (safepoints.length() > 0) {
850 SafePointNode* sfpt = safepoints.pop();
851 Node* mem = sfpt->memory();
852 Node* ctl = sfpt->control();
853 assert(sfpt->jvms() != NULL, "missed JVMS");
854 // Fields of scalar objs are referenced only at the end
855 // of regular debuginfo at the last (youngest) JVMS.
856 // Record relative start index.
857 uint first_ind = (sfpt->req() - sfpt->jvms()->scloff());
858 SafePointScalarObjectNode* sobj = new SafePointScalarObjectNode(res_type,
859 #ifdef ASSERT
860 alloc,
861 #endif
862 first_ind, nfields);
863 sobj->init_req(0, C->root());
864 transform_later(sobj);
865
866 // Scan object's fields adding an input to the safepoint for each field.
867 for (int j = 0; j < nfields; j++) {
868 intptr_t offset;
869 ciField* field = NULL;
870 if (iklass != NULL) {
871 field = iklass->nonstatic_field_at(j);
872 offset = field->offset();
873 elem_type = field->type();
874 basic_elem_type = field->layout_type();
875 } else {
876 offset = array_base + j * (intptr_t)element_size;
877 }
878
879 const Type *field_type;
880 // The next code is taken from Parse::do_get_xxx().
881 if (basic_elem_type == T_OBJECT || basic_elem_type == T_ARRAY) {
882 if (!elem_type->is_loaded()) {
883 field_type = TypeInstPtr::BOTTOM;
884 } else if (field != NULL && field->is_static_constant()) {
885 // This can happen if the constant oop is non-perm.
886 ciObject* con = field->constant_value().as_object();
887 // Do not "join" in the previous type; it doesn't add value,
888 // and may yield a vacuous result if the field is of interface type.
889 field_type = TypeOopPtr::make_from_constant(con)->isa_oopptr();
890 assert(field_type != NULL, "field singleton type must be consistent");
891 } else {
892 field_type = TypeOopPtr::make_from_klass(elem_type->as_klass());
893 }
894 if (UseCompressedOops) {
895 field_type = field_type->make_narrowoop();
896 basic_elem_type = T_NARROWOOP;
897 }
898 } else {
899 field_type = Type::get_const_basic_type(basic_elem_type);
900 }
901
902 const TypeOopPtr *field_addr_type = res_type->add_offset(offset)->isa_oopptr();
903
904 Node *field_val = value_from_mem(mem, ctl, basic_elem_type, field_type, field_addr_type, alloc);
905 if (field_val == NULL) {
906 // We weren't able to find a value for this field,
907 // give up on eliminating this allocation.
908
909 // Remove any extra entries we added to the safepoint.
910 uint last = sfpt->req() - 1;
911 for (int k = 0; k < j; k++) {
912 sfpt->del_req(last--);
913 }
914 _igvn._worklist.push(sfpt);
915 // rollback processed safepoints
916 while (safepoints_done.length() > 0) {
917 SafePointNode* sfpt_done = safepoints_done.pop();
918 // remove any extra entries we added to the safepoint
919 last = sfpt_done->req() - 1;
920 for (int k = 0; k < nfields; k++) {
921 sfpt_done->del_req(last--);
922 }
923 JVMState *jvms = sfpt_done->jvms();
924 jvms->set_endoff(sfpt_done->req());
925 // Now make a pass over the debug information replacing any references
926 // to SafePointScalarObjectNode with the allocated object.
927 int start = jvms->debug_start();
928 int end = jvms->debug_end();
929 for (int i = start; i < end; i++) {
930 if (sfpt_done->in(i)->is_SafePointScalarObject()) {
931 SafePointScalarObjectNode* scobj = sfpt_done->in(i)->as_SafePointScalarObject();
932 if (scobj->first_index(jvms) == sfpt_done->req() &&
933 scobj->n_fields() == (uint)nfields) {
934 assert(scobj->alloc() == alloc, "sanity");
935 sfpt_done->set_req(i, res);
936 }
937 }
938 }
939 _igvn._worklist.push(sfpt_done);
940 }
941 #ifndef PRODUCT
942 if (PrintEliminateAllocations) {
943 if (field != NULL) {
944 tty->print("=== At SafePoint node %d can't find value of Field: ",
945 sfpt->_idx);
946 field->print();
947 int field_idx = C->get_alias_index(field_addr_type);
948 tty->print(" (alias_idx=%d)", field_idx);
949 } else { // Array's element
950 tty->print("=== At SafePoint node %d can't find value of array element [%d]",
951 sfpt->_idx, j);
952 }
953 tty->print(", which prevents elimination of: ");
954 if (res == NULL)
955 alloc->dump();
956 else
957 res->dump();
958 }
959 #endif
960 return false;
961 }
962 if (UseCompressedOops && field_type->isa_narrowoop()) {
963 // Enable "DecodeN(EncodeP(Allocate)) --> Allocate" transformation
964 // to be able scalar replace the allocation.
965 if (field_val->is_EncodeP()) {
966 field_val = field_val->in(1);
967 } else {
968 field_val = transform_later(new DecodeNNode(field_val, field_val->get_ptr_type()));
969 }
970 }
971 sfpt->add_req(field_val);
972 }
973 JVMState *jvms = sfpt->jvms();
974 jvms->set_endoff(sfpt->req());
975 // Now make a pass over the debug information replacing any references
976 // to the allocated object with "sobj"
977 int start = jvms->debug_start();
978 int end = jvms->debug_end();
979 sfpt->replace_edges_in_range(res, sobj, start, end);
980 _igvn._worklist.push(sfpt);
981 safepoints_done.append_if_missing(sfpt); // keep it for rollback
982 }
983 return true;
984 }
985
986 static void disconnect_projections(MultiNode* n, PhaseIterGVN& igvn) {
987 Node* ctl_proj = n->proj_out(TypeFunc::Control);
988 Node* mem_proj = n->proj_out(TypeFunc::Memory);
989 if (ctl_proj != NULL) {
990 igvn.replace_node(ctl_proj, n->in(0));
991 }
992 if (mem_proj != NULL) {
993 igvn.replace_node(mem_proj, n->in(TypeFunc::Memory));
994 }
995 }
996
997 // Process users of eliminated allocation.
998 void PhaseMacroExpand::process_users_of_allocation(CallNode *alloc) {
999 Node* res = alloc->result_cast();
1000 if (res != NULL) {
1001 for (DUIterator_Last jmin, j = res->last_outs(jmin); j >= jmin; ) {
1002 Node *use = res->last_out(j);
1003 uint oc1 = res->outcnt();
1004
1005 if (use->is_AddP()) {
1006 for (DUIterator_Last kmin, k = use->last_outs(kmin); k >= kmin; ) {
1007 Node *n = use->last_out(k);
1008 uint oc2 = use->outcnt();
1009 if (n->is_Store()) {
1010 #ifdef ASSERT
1011 // Verify that there is no dependent MemBarVolatile nodes,
1012 // they should be removed during IGVN, see MemBarNode::Ideal().
1013 for (DUIterator_Fast pmax, p = n->fast_outs(pmax);
1014 p < pmax; p++) {
1015 Node* mb = n->fast_out(p);
1016 assert(mb->is_Initialize() || !mb->is_MemBar() ||
1017 mb->req() <= MemBarNode::Precedent ||
1018 mb->in(MemBarNode::Precedent) != n,
1019 "MemBarVolatile should be eliminated for non-escaping object");
1020 }
1021 #endif
1022 _igvn.replace_node(n, n->in(MemNode::Memory));
1023 } else if (n->is_ArrayCopy()) {
1024 // Disconnect ArrayCopy node
1025 ArrayCopyNode* ac = n->as_ArrayCopy();
1026 assert(ac->is_clonebasic(), "unexpected array copy kind");
1027 Node* membar_after = ac->proj_out(TypeFunc::Control)->unique_ctrl_out();
1028 disconnect_projections(ac, _igvn);
1029 assert(alloc->in(0)->is_Proj() && alloc->in(0)->in(0)->Opcode() == Op_MemBarCPUOrder, "mem barrier expected before allocation");
1030 Node* membar_before = alloc->in(0)->in(0);
1031 disconnect_projections(membar_before->as_MemBar(), _igvn);
1032 if (membar_after->is_MemBar()) {
1033 disconnect_projections(membar_after->as_MemBar(), _igvn);
1034 }
1035 } else if (n->is_g1_wb_pre_call()) {
1036 eliminate_g1_wb_pre(n);
1037 } else {
1038 eliminate_card_mark(n);
1039 }
1040 k -= (oc2 - use->outcnt());
1041 }
1042 _igvn.remove_dead_node(use);
1043 } else if (use->is_ArrayCopy()) {
1044 // Disconnect ArrayCopy node
1045 ArrayCopyNode* ac = use->as_ArrayCopy();
1046 assert(ac->is_arraycopy_validated() ||
1047 ac->is_copyof_validated() ||
1048 ac->is_copyofrange_validated(), "unsupported");
1049 CallProjections callprojs;
1050 ac->extract_projections(&callprojs, true);
1051
1052 _igvn.replace_node(callprojs.fallthrough_ioproj, ac->in(TypeFunc::I_O));
1053 _igvn.replace_node(callprojs.fallthrough_memproj, ac->in(TypeFunc::Memory));
1054 _igvn.replace_node(callprojs.fallthrough_catchproj, ac->in(TypeFunc::Control));
1055
1056 // Set control to top. IGVN will remove the remaining projections
1057 ac->set_req(0, top());
1058 ac->replace_edge(res, top());
1059
1060 // Disconnect src right away: it can help find new
1061 // opportunities for allocation elimination
1062 Node* src = ac->in(ArrayCopyNode::Src);
1063 ac->replace_edge(src, top());
1064 if (src->outcnt() == 0) {
1065 _igvn.remove_dead_node(src);
1066 }
1067
1068 _igvn._worklist.push(ac);
1069 } else {
1070 eliminate_card_mark(use);
1071 }
1072 j -= (oc1 - res->outcnt());
1073 }
1074 assert(res->outcnt() == 0, "all uses of allocated objects must be deleted");
1075 _igvn.remove_dead_node(res);
1076 }
1077
1078 //
1079 // Process other users of allocation's projections
1080 //
1081 if (_resproj != NULL && _resproj->outcnt() != 0) {
1082 // First disconnect stores captured by Initialize node.
1083 // If Initialize node is eliminated first in the following code,
1084 // it will kill such stores and DUIterator_Last will assert.
1085 for (DUIterator_Fast jmax, j = _resproj->fast_outs(jmax); j < jmax; j++) {
1086 Node *use = _resproj->fast_out(j);
1087 if (use->is_AddP()) {
1088 // raw memory addresses used only by the initialization
1089 _igvn.replace_node(use, C->top());
1090 --j; --jmax;
1091 }
1092 }
1093 for (DUIterator_Last jmin, j = _resproj->last_outs(jmin); j >= jmin; ) {
1094 Node *use = _resproj->last_out(j);
1095 uint oc1 = _resproj->outcnt();
1096 if (use->is_Initialize()) {
1097 // Eliminate Initialize node.
1098 InitializeNode *init = use->as_Initialize();
1099 assert(init->outcnt() <= 2, "only a control and memory projection expected");
1100 Node *ctrl_proj = init->proj_out(TypeFunc::Control);
1101 if (ctrl_proj != NULL) {
1102 assert(init->in(TypeFunc::Control) == _fallthroughcatchproj, "allocation control projection");
1103 _igvn.replace_node(ctrl_proj, _fallthroughcatchproj);
1104 }
1105 Node *mem_proj = init->proj_out(TypeFunc::Memory);
1106 if (mem_proj != NULL) {
1107 Node *mem = init->in(TypeFunc::Memory);
1108 #ifdef ASSERT
1109 if (mem->is_MergeMem()) {
1110 assert(mem->in(TypeFunc::Memory) == _memproj_fallthrough, "allocation memory projection");
1111 } else {
1112 assert(mem == _memproj_fallthrough, "allocation memory projection");
1113 }
1114 #endif
1115 _igvn.replace_node(mem_proj, mem);
1116 }
1117 } else {
1118 assert(false, "only Initialize or AddP expected");
1119 }
1120 j -= (oc1 - _resproj->outcnt());
1121 }
1122 }
1123 if (_fallthroughcatchproj != NULL) {
1124 _igvn.replace_node(_fallthroughcatchproj, alloc->in(TypeFunc::Control));
1125 }
1126 if (_memproj_fallthrough != NULL) {
1127 _igvn.replace_node(_memproj_fallthrough, alloc->in(TypeFunc::Memory));
1128 }
1129 if (_memproj_catchall != NULL) {
1130 _igvn.replace_node(_memproj_catchall, C->top());
1131 }
1132 if (_ioproj_fallthrough != NULL) {
1133 _igvn.replace_node(_ioproj_fallthrough, alloc->in(TypeFunc::I_O));
1134 }
1135 if (_ioproj_catchall != NULL) {
1136 _igvn.replace_node(_ioproj_catchall, C->top());
1137 }
1138 if (_catchallcatchproj != NULL) {
1139 _igvn.replace_node(_catchallcatchproj, C->top());
1140 }
1141 }
1142
1143 bool PhaseMacroExpand::eliminate_allocate_node(AllocateNode *alloc) {
1144 // Don't do scalar replacement if the frame can be popped by JVMTI:
1145 // if reallocation fails during deoptimization we'll pop all
1146 // interpreter frames for this compiled frame and that won't play
1147 // nice with JVMTI popframe.
1148 if (!EliminateAllocations || JvmtiExport::can_pop_frame() || !alloc->_is_non_escaping) {
1149 return false;
1150 }
1151 Node* klass = alloc->in(AllocateNode::KlassNode);
1152 const TypeKlassPtr* tklass = _igvn.type(klass)->is_klassptr();
1153 Node* res = alloc->result_cast();
1154 // Eliminate boxing allocations which are not used
1155 // regardless scalar replacable status.
1156 bool boxing_alloc = C->eliminate_boxing() &&
1157 tklass->klass()->is_instance_klass() &&
1158 tklass->klass()->as_instance_klass()->is_box_klass();
1159 if (!alloc->_is_scalar_replaceable && (!boxing_alloc || (res != NULL))) {
1160 return false;
1161 }
1162
1163 extract_call_projections(alloc);
1164
1165 GrowableArray <SafePointNode *> safepoints;
1166 if (!can_eliminate_allocation(alloc, safepoints)) {
1167 return false;
1168 }
1169
1170 if (!alloc->_is_scalar_replaceable) {
1171 assert(res == NULL, "sanity");
1172 // We can only eliminate allocation if all debug info references
1173 // are already replaced with SafePointScalarObject because
1174 // we can't search for a fields value without instance_id.
1175 if (safepoints.length() > 0) {
1176 return false;
1177 }
1178 }
1179
1180 if (!scalar_replacement(alloc, safepoints)) {
1181 return false;
1182 }
1183
1184 CompileLog* log = C->log();
1185 if (log != NULL) {
1186 log->head("eliminate_allocation type='%d'",
1187 log->identify(tklass->klass()));
1188 JVMState* p = alloc->jvms();
1189 while (p != NULL) {
1190 log->elem("jvms bci='%d' method='%d'", p->bci(), log->identify(p->method()));
1191 p = p->caller();
1192 }
1193 log->tail("eliminate_allocation");
1194 }
1195
1196 process_users_of_allocation(alloc);
1197
1198 #ifndef PRODUCT
1199 if (PrintEliminateAllocations) {
1200 if (alloc->is_AllocateArray())
1201 tty->print_cr("++++ Eliminated: %d AllocateArray", alloc->_idx);
1202 else
1203 tty->print_cr("++++ Eliminated: %d Allocate", alloc->_idx);
1204 }
1205 #endif
1206
1207 return true;
1208 }
1209
1210 bool PhaseMacroExpand::eliminate_boxing_node(CallStaticJavaNode *boxing) {
1211 // EA should remove all uses of non-escaping boxing node.
1212 if (!C->eliminate_boxing() || boxing->proj_out(TypeFunc::Parms) != NULL) {
1213 return false;
1214 }
1215
1216 assert(boxing->result_cast() == NULL, "unexpected boxing node result");
1217
1218 extract_call_projections(boxing);
1219
1220 const TypeTuple* r = boxing->tf()->range();
1221 assert(r->cnt() > TypeFunc::Parms, "sanity");
1222 const TypeInstPtr* t = r->field_at(TypeFunc::Parms)->isa_instptr();
1223 assert(t != NULL, "sanity");
1224
1225 CompileLog* log = C->log();
1226 if (log != NULL) {
1227 log->head("eliminate_boxing type='%d'",
1228 log->identify(t->klass()));
1229 JVMState* p = boxing->jvms();
1230 while (p != NULL) {
1231 log->elem("jvms bci='%d' method='%d'", p->bci(), log->identify(p->method()));
1232 p = p->caller();
1233 }
1234 log->tail("eliminate_boxing");
1235 }
1236
1237 process_users_of_allocation(boxing);
1238
1239 #ifndef PRODUCT
1240 if (PrintEliminateAllocations) {
1241 tty->print("++++ Eliminated: %d ", boxing->_idx);
1242 boxing->method()->print_short_name(tty);
1243 tty->cr();
1244 }
1245 #endif
1246
1247 return true;
1248 }
1249
1250 //---------------------------set_eden_pointers-------------------------
1251 void PhaseMacroExpand::set_eden_pointers(Node* &eden_top_adr, Node* &eden_end_adr) {
1252 if (UseTLAB) { // Private allocation: load from TLS
1253 Node* thread = transform_later(new ThreadLocalNode());
1254 int tlab_top_offset = in_bytes(JavaThread::tlab_top_offset());
1255 int tlab_end_offset = in_bytes(JavaThread::tlab_end_offset());
1256 eden_top_adr = basic_plus_adr(top()/*not oop*/, thread, tlab_top_offset);
1257 eden_end_adr = basic_plus_adr(top()/*not oop*/, thread, tlab_end_offset);
1258 } else { // Shared allocation: load from globals
1259 CollectedHeap* ch = Universe::heap();
1260 address top_adr = (address)ch->top_addr();
1261 address end_adr = (address)ch->end_addr();
1262 eden_top_adr = makecon(TypeRawPtr::make(top_adr));
1263 eden_end_adr = basic_plus_adr(eden_top_adr, end_adr - top_adr);
1264 }
1265 }
1266
1267
1268 Node* PhaseMacroExpand::make_load(Node* ctl, Node* mem, Node* base, int offset, const Type* value_type, BasicType bt) {
1269 Node* adr = basic_plus_adr(base, offset);
1270 const TypePtr* adr_type = adr->bottom_type()->is_ptr();
1271 Node* value = LoadNode::make(_igvn, ctl, mem, adr, adr_type, value_type, bt, MemNode::unordered);
1272 transform_later(value);
1273 return value;
1274 }
1275
1276
1277 Node* PhaseMacroExpand::make_store(Node* ctl, Node* mem, Node* base, int offset, Node* value, BasicType bt) {
1278 Node* adr = basic_plus_adr(base, offset);
1279 mem = StoreNode::make(_igvn, ctl, mem, adr, NULL, value, bt, MemNode::unordered);
1280 transform_later(mem);
1281 return mem;
1282 }
1283
1284 //=============================================================================
1285 //
1286 // A L L O C A T I O N
1287 //
1288 // Allocation attempts to be fast in the case of frequent small objects.
1289 // It breaks down like this:
1290 //
1291 // 1) Size in doublewords is computed. This is a constant for objects and
1292 // variable for most arrays. Doubleword units are used to avoid size
1293 // overflow of huge doubleword arrays. We need doublewords in the end for
1294 // rounding.
1295 //
1296 // 2) Size is checked for being 'too large'. Too-large allocations will go
1297 // the slow path into the VM. The slow path can throw any required
1298 // exceptions, and does all the special checks for very large arrays. The
1299 // size test can constant-fold away for objects. For objects with
1300 // finalizers it constant-folds the otherway: you always go slow with
1301 // finalizers.
1302 //
1303 // 3) If NOT using TLABs, this is the contended loop-back point.
1304 // Load-Locked the heap top. If using TLABs normal-load the heap top.
1305 //
1306 // 4) Check that heap top + size*8 < max. If we fail go the slow ` route.
1307 // NOTE: "top+size*8" cannot wrap the 4Gig line! Here's why: for largish
1308 // "size*8" we always enter the VM, where "largish" is a constant picked small
1309 // enough that there's always space between the eden max and 4Gig (old space is
1310 // there so it's quite large) and large enough that the cost of entering the VM
1311 // is dwarfed by the cost to initialize the space.
1312 //
1313 // 5) If NOT using TLABs, Store-Conditional the adjusted heap top back
1314 // down. If contended, repeat at step 3. If using TLABs normal-store
1315 // adjusted heap top back down; there is no contention.
1316 //
1317 // 6) If !ZeroTLAB then Bulk-clear the object/array. Fill in klass & mark
1318 // fields.
1319 //
1320 // 7) Merge with the slow-path; cast the raw memory pointer to the correct
1321 // oop flavor.
1322 //
1323 //=============================================================================
1324 // FastAllocateSizeLimit value is in DOUBLEWORDS.
1325 // Allocations bigger than this always go the slow route.
1326 // This value must be small enough that allocation attempts that need to
1327 // trigger exceptions go the slow route. Also, it must be small enough so
1328 // that heap_top + size_in_bytes does not wrap around the 4Gig limit.
1329 //=============================================================================j//
1330 // %%% Here is an old comment from parseHelper.cpp; is it outdated?
1331 // The allocator will coalesce int->oop copies away. See comment in
1332 // coalesce.cpp about how this works. It depends critically on the exact
1333 // code shape produced here, so if you are changing this code shape
1334 // make sure the GC info for the heap-top is correct in and around the
1335 // slow-path call.
1336 //
1337
1338 void PhaseMacroExpand::expand_allocate_common(
1339 AllocateNode* alloc, // allocation node to be expanded
1340 Node* length, // array length for an array allocation
1341 const TypeFunc* slow_call_type, // Type of slow call
1342 address slow_call_address // Address of slow call
1343 )
1344 {
1345
1346 Node* ctrl = alloc->in(TypeFunc::Control);
1347 Node* mem = alloc->in(TypeFunc::Memory);
1348 Node* i_o = alloc->in(TypeFunc::I_O);
1349 Node* size_in_bytes = alloc->in(AllocateNode::AllocSize);
1350 Node* klass_node = alloc->in(AllocateNode::KlassNode);
1351 Node* initial_slow_test = alloc->in(AllocateNode::InitialTest);
1352
1353 assert(ctrl != NULL, "must have control");
1354 // We need a Region and corresponding Phi's to merge the slow-path and fast-path results.
1355 // they will not be used if "always_slow" is set
1356 enum { slow_result_path = 1, fast_result_path = 2 };
1357 Node *result_region = NULL;
1358 Node *result_phi_rawmem = NULL;
1359 Node *result_phi_rawoop = NULL;
1360 Node *result_phi_i_o = NULL;
1361
1362 // The initial slow comparison is a size check, the comparison
1363 // we want to do is a BoolTest::gt
1364 bool always_slow = false;
1365 int tv = _igvn.find_int_con(initial_slow_test, -1);
1366 if (tv >= 0) {
1367 always_slow = (tv == 1);
1368 initial_slow_test = NULL;
1369 } else {
1370 initial_slow_test = BoolNode::make_predicate(initial_slow_test, &_igvn);
1371 }
1372
1373 if (C->env()->dtrace_alloc_probes() ||
1374 !UseTLAB && (!Universe::heap()->supports_inline_contig_alloc())) {
1375 // Force slow-path allocation
1376 always_slow = true;
1377 initial_slow_test = NULL;
1378 }
1379
1380
1381 enum { too_big_or_final_path = 1, need_gc_path = 2 };
1382 Node *slow_region = NULL;
1383 Node *toobig_false = ctrl;
1384
1385 assert (initial_slow_test == NULL || !always_slow, "arguments must be consistent");
1386 // generate the initial test if necessary
1387 if (initial_slow_test != NULL ) {
1388 slow_region = new RegionNode(3);
1389
1390 // Now make the initial failure test. Usually a too-big test but
1391 // might be a TRUE for finalizers or a fancy class check for
1392 // newInstance0.
1393 IfNode *toobig_iff = new IfNode(ctrl, initial_slow_test, PROB_MIN, COUNT_UNKNOWN);
1394 transform_later(toobig_iff);
1395 // Plug the failing-too-big test into the slow-path region
1396 Node *toobig_true = new IfTrueNode( toobig_iff );
1397 transform_later(toobig_true);
1398 slow_region ->init_req( too_big_or_final_path, toobig_true );
1399 toobig_false = new IfFalseNode( toobig_iff );
1400 transform_later(toobig_false);
1401 } else { // No initial test, just fall into next case
1402 toobig_false = ctrl;
1403 debug_only(slow_region = NodeSentinel);
1404 }
1405
1406 Node *slow_mem = mem; // save the current memory state for slow path
1407 // generate the fast allocation code unless we know that the initial test will always go slow
1408 if (!always_slow) {
1409 // Fast path modifies only raw memory.
1410 if (mem->is_MergeMem()) {
1411 mem = mem->as_MergeMem()->memory_at(Compile::AliasIdxRaw);
1412 }
1413
1414 Node* eden_top_adr;
1415 Node* eden_end_adr;
1416
1417 set_eden_pointers(eden_top_adr, eden_end_adr);
1418
1419 // Load Eden::end. Loop invariant and hoisted.
1420 //
1421 // Note: We set the control input on "eden_end" and "old_eden_top" when using
1422 // a TLAB to work around a bug where these values were being moved across
1423 // a safepoint. These are not oops, so they cannot be include in the oop
1424 // map, but they can be changed by a GC. The proper way to fix this would
1425 // be to set the raw memory state when generating a SafepointNode. However
1426 // this will require extensive changes to the loop optimization in order to
1427 // prevent a degradation of the optimization.
1428 // See comment in memnode.hpp, around line 227 in class LoadPNode.
1429 Node *eden_end = make_load(ctrl, mem, eden_end_adr, 0, TypeRawPtr::BOTTOM, T_ADDRESS);
1430
1431 // allocate the Region and Phi nodes for the result
1432 result_region = new RegionNode(3);
1433 result_phi_rawmem = new PhiNode(result_region, Type::MEMORY, TypeRawPtr::BOTTOM);
1434 result_phi_rawoop = new PhiNode(result_region, TypeRawPtr::BOTTOM);
1435 result_phi_i_o = new PhiNode(result_region, Type::ABIO); // I/O is used for Prefetch
1436
1437 // We need a Region for the loop-back contended case.
1438 enum { fall_in_path = 1, contended_loopback_path = 2 };
1439 Node *contended_region;
1440 Node *contended_phi_rawmem;
1441 if (UseTLAB) {
1442 contended_region = toobig_false;
1443 contended_phi_rawmem = mem;
1444 } else {
1445 contended_region = new RegionNode(3);
1446 contended_phi_rawmem = new PhiNode(contended_region, Type::MEMORY, TypeRawPtr::BOTTOM);
1447 // Now handle the passing-too-big test. We fall into the contended
1448 // loop-back merge point.
1449 contended_region ->init_req(fall_in_path, toobig_false);
1450 contended_phi_rawmem->init_req(fall_in_path, mem);
1451 transform_later(contended_region);
1452 transform_later(contended_phi_rawmem);
1453 }
1454
1455 // Load(-locked) the heap top.
1456 // See note above concerning the control input when using a TLAB
1457 Node *old_eden_top = UseTLAB
1458 ? new LoadPNode (ctrl, contended_phi_rawmem, eden_top_adr, TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM, MemNode::unordered)
1459 : new LoadPLockedNode(contended_region, contended_phi_rawmem, eden_top_adr, MemNode::acquire);
1460
1461 transform_later(old_eden_top);
1462 // Add to heap top to get a new heap top
1463
1464 Node* init_size_in_bytes = size_in_bytes;
1465 if (UseShenandoahGC) {
1466 // Allocate several words more for the Shenandoah brooks pointer.
1467 size_in_bytes = new AddLNode(size_in_bytes, _igvn.MakeConX(BrooksPointer::byte_size()));
1468 transform_later(size_in_bytes);
1469 }
1470
1471 Node *new_eden_top = new AddPNode(top(), old_eden_top, size_in_bytes);
1472 transform_later(new_eden_top);
1473 // Check for needing a GC; compare against heap end
1474 Node *needgc_cmp = new CmpPNode(new_eden_top, eden_end);
1475 transform_later(needgc_cmp);
1476 Node *needgc_bol = new BoolNode(needgc_cmp, BoolTest::ge);
1477 transform_later(needgc_bol);
1478 IfNode *needgc_iff = new IfNode(contended_region, needgc_bol, PROB_UNLIKELY_MAG(4), COUNT_UNKNOWN);
1479 transform_later(needgc_iff);
1480
1481 // Plug the failing-heap-space-need-gc test into the slow-path region
1482 Node *needgc_true = new IfTrueNode(needgc_iff);
1483 transform_later(needgc_true);
1484 if (initial_slow_test) {
1485 slow_region->init_req(need_gc_path, needgc_true);
1486 // This completes all paths into the slow merge point
1487 transform_later(slow_region);
1488 } else { // No initial slow path needed!
1489 // Just fall from the need-GC path straight into the VM call.
1490 slow_region = needgc_true;
1491 }
1492 // No need for a GC. Setup for the Store-Conditional
1493 Node *needgc_false = new IfFalseNode(needgc_iff);
1494 transform_later(needgc_false);
1495
1496 // Grab regular I/O before optional prefetch may change it.
1497 // Slow-path does no I/O so just set it to the original I/O.
1498 result_phi_i_o->init_req(slow_result_path, i_o);
1499
1500 i_o = prefetch_allocation(i_o, needgc_false, contended_phi_rawmem,
1501 old_eden_top, new_eden_top, length);
1502
1503 // Name successful fast-path variables
1504 Node* fast_oop = old_eden_top;
1505 Node* fast_oop_ctrl;
1506 Node* fast_oop_rawmem;
1507
1508 // Store (-conditional) the modified eden top back down.
1509 // StorePConditional produces flags for a test PLUS a modified raw
1510 // memory state.
1511 if (UseTLAB) {
1512 Node* store_eden_top =
1513 new StorePNode(needgc_false, contended_phi_rawmem, eden_top_adr,
1514 TypeRawPtr::BOTTOM, new_eden_top, MemNode::unordered);
1515 transform_later(store_eden_top);
1516 fast_oop_ctrl = needgc_false; // No contention, so this is the fast path
1517 fast_oop_rawmem = store_eden_top;
1518 } else {
1519 Node* store_eden_top =
1520 new StorePConditionalNode(needgc_false, contended_phi_rawmem, eden_top_adr,
1521 new_eden_top, fast_oop/*old_eden_top*/);
1522 transform_later(store_eden_top);
1523 Node *contention_check = new BoolNode(store_eden_top, BoolTest::ne);
1524 transform_later(contention_check);
1525 store_eden_top = new SCMemProjNode(store_eden_top);
1526 transform_later(store_eden_top);
1527
1528 // If not using TLABs, check to see if there was contention.
1529 IfNode *contention_iff = new IfNode (needgc_false, contention_check, PROB_MIN, COUNT_UNKNOWN);
1530 transform_later(contention_iff);
1531 Node *contention_true = new IfTrueNode(contention_iff);
1532 transform_later(contention_true);
1533 // If contention, loopback and try again.
1534 contended_region->init_req(contended_loopback_path, contention_true);
1535 contended_phi_rawmem->init_req(contended_loopback_path, store_eden_top);
1536
1537 // Fast-path succeeded with no contention!
1538 Node *contention_false = new IfFalseNode(contention_iff);
1539 transform_later(contention_false);
1540 fast_oop_ctrl = contention_false;
1541
1542 // Bump total allocated bytes for this thread
1543 Node* thread = new ThreadLocalNode();
1544 transform_later(thread);
1545 Node* alloc_bytes_adr = basic_plus_adr(top()/*not oop*/, thread,
1546 in_bytes(JavaThread::allocated_bytes_offset()));
1547 Node* alloc_bytes = make_load(fast_oop_ctrl, store_eden_top, alloc_bytes_adr,
1548 0, TypeLong::LONG, T_LONG);
1549 #ifdef _LP64
1550 Node* alloc_size = size_in_bytes;
1551 #else
1552 Node* alloc_size = new ConvI2LNode(size_in_bytes);
1553 transform_later(alloc_size);
1554 #endif
1555 Node* new_alloc_bytes = new AddLNode(alloc_bytes, alloc_size);
1556 transform_later(new_alloc_bytes);
1557 fast_oop_rawmem = make_store(fast_oop_ctrl, store_eden_top, alloc_bytes_adr,
1558 0, new_alloc_bytes, T_LONG);
1559 }
1560
1561 if (UseShenandoahGC) {
1562 // Bump up object for Shenandoah brooks pointer.
1563 fast_oop = new AddPNode(top(), fast_oop, _igvn.MakeConX(BrooksPointer::byte_size()));
1564 transform_later(fast_oop);
1565 }
1566
1567 InitializeNode* init = alloc->initialization();
1568 fast_oop_rawmem = initialize_object(alloc,
1569 fast_oop_ctrl, fast_oop_rawmem, fast_oop,
1570 klass_node, length, init_size_in_bytes);
1571
1572 // If initialization is performed by an array copy, any required
1573 // MemBarStoreStore was already added. If the object does not
1574 // escape no need for a MemBarStoreStore. If the object does not
1575 // escape in its initializer and memory barrier (MemBarStoreStore or
1576 // stronger) is already added at exit of initializer, also no need
1577 // for a MemBarStoreStore. Otherwise we need a MemBarStoreStore
1578 // so that stores that initialize this object can't be reordered
1579 // with a subsequent store that makes this object accessible by
1580 // other threads.
1581 // Other threads include java threads and JVM internal threads
1582 // (for example concurrent GC threads). Current concurrent GC
1583 // implementation: CMS and G1 will not scan newly created object,
1584 // so it's safe to skip storestore barrier when allocation does
1585 // not escape.
1586 if (!alloc->does_not_escape_thread() &&
1587 !alloc->is_allocation_MemBar_redundant() &&
1588 (init == NULL || !init->is_complete_with_arraycopy())) {
1589 if (init == NULL || init->req() < InitializeNode::RawStores) {
1590 // No InitializeNode or no stores captured by zeroing
1591 // elimination. Simply add the MemBarStoreStore after object
1592 // initialization.
1593 MemBarNode* mb = MemBarNode::make(C, Op_MemBarStoreStore, Compile::AliasIdxBot);
1594 transform_later(mb);
1595
1596 mb->init_req(TypeFunc::Memory, fast_oop_rawmem);
1597 mb->init_req(TypeFunc::Control, fast_oop_ctrl);
1598 fast_oop_ctrl = new ProjNode(mb,TypeFunc::Control);
1599 transform_later(fast_oop_ctrl);
1600 fast_oop_rawmem = new ProjNode(mb,TypeFunc::Memory);
1601 transform_later(fast_oop_rawmem);
1602 } else {
1603 // Add the MemBarStoreStore after the InitializeNode so that
1604 // all stores performing the initialization that were moved
1605 // before the InitializeNode happen before the storestore
1606 // barrier.
1607
1608 Node* init_ctrl = init->proj_out(TypeFunc::Control);
1609 Node* init_mem = init->proj_out(TypeFunc::Memory);
1610
1611 MemBarNode* mb = MemBarNode::make(C, Op_MemBarStoreStore, Compile::AliasIdxBot);
1612 transform_later(mb);
1613
1614 Node* ctrl = new ProjNode(init,TypeFunc::Control);
1615 transform_later(ctrl);
1616 Node* mem = new ProjNode(init,TypeFunc::Memory);
1617 transform_later(mem);
1618
1619 // The MemBarStoreStore depends on control and memory coming
1620 // from the InitializeNode
1621 mb->init_req(TypeFunc::Memory, mem);
1622 mb->init_req(TypeFunc::Control, ctrl);
1623
1624 ctrl = new ProjNode(mb,TypeFunc::Control);
1625 transform_later(ctrl);
1626 mem = new ProjNode(mb,TypeFunc::Memory);
1627 transform_later(mem);
1628
1629 // All nodes that depended on the InitializeNode for control
1630 // and memory must now depend on the MemBarNode that itself
1631 // depends on the InitializeNode
1632 if (init_ctrl != NULL) {
1633 _igvn.replace_node(init_ctrl, ctrl);
1634 }
1635 if (init_mem != NULL) {
1636 _igvn.replace_node(init_mem, mem);
1637 }
1638 }
1639 }
1640
1641 if (C->env()->dtrace_extended_probes()) {
1642 // Slow-path call
1643 int size = TypeFunc::Parms + 2;
1644 CallLeafNode *call = new CallLeafNode(OptoRuntime::dtrace_object_alloc_Type(),
1645 CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_object_alloc_base),
1646 "dtrace_object_alloc",
1647 TypeRawPtr::BOTTOM);
1648
1649 // Get base of thread-local storage area
1650 Node* thread = new ThreadLocalNode();
1651 transform_later(thread);
1652
1653 call->init_req(TypeFunc::Parms+0, thread);
1654 call->init_req(TypeFunc::Parms+1, fast_oop);
1655 call->init_req(TypeFunc::Control, fast_oop_ctrl);
1656 call->init_req(TypeFunc::I_O , top()); // does no i/o
1657 call->init_req(TypeFunc::Memory , fast_oop_rawmem);
1658 call->init_req(TypeFunc::ReturnAdr, alloc->in(TypeFunc::ReturnAdr));
1659 call->init_req(TypeFunc::FramePtr, alloc->in(TypeFunc::FramePtr));
1660 transform_later(call);
1661 fast_oop_ctrl = new ProjNode(call,TypeFunc::Control);
1662 transform_later(fast_oop_ctrl);
1663 fast_oop_rawmem = new ProjNode(call,TypeFunc::Memory);
1664 transform_later(fast_oop_rawmem);
1665 }
1666
1667 // Plug in the successful fast-path into the result merge point
1668 result_region ->init_req(fast_result_path, fast_oop_ctrl);
1669 result_phi_rawoop->init_req(fast_result_path, fast_oop);
1670 result_phi_i_o ->init_req(fast_result_path, i_o);
1671 result_phi_rawmem->init_req(fast_result_path, fast_oop_rawmem);
1672 } else {
1673 slow_region = ctrl;
1674 result_phi_i_o = i_o; // Rename it to use in the following code.
1675 }
1676
1677 // Generate slow-path call
1678 CallNode *call = new CallStaticJavaNode(slow_call_type, slow_call_address,
1679 OptoRuntime::stub_name(slow_call_address),
1680 alloc->jvms()->bci(),
1681 TypePtr::BOTTOM);
1682 call->init_req( TypeFunc::Control, slow_region );
1683 call->init_req( TypeFunc::I_O , top() ) ; // does no i/o
1684 call->init_req( TypeFunc::Memory , slow_mem ); // may gc ptrs
1685 call->init_req( TypeFunc::ReturnAdr, alloc->in(TypeFunc::ReturnAdr) );
1686 call->init_req( TypeFunc::FramePtr, alloc->in(TypeFunc::FramePtr) );
1687
1688 call->init_req(TypeFunc::Parms+0, klass_node);
1689 if (length != NULL) {
1690 call->init_req(TypeFunc::Parms+1, length);
1691 }
1692
1693 // Copy debug information and adjust JVMState information, then replace
1694 // allocate node with the call
1695 copy_call_debug_info((CallNode *) alloc, call);
1696 if (!always_slow) {
1697 call->set_cnt(PROB_UNLIKELY_MAG(4)); // Same effect as RC_UNCOMMON.
1698 } else {
1699 // Hook i_o projection to avoid its elimination during allocation
1700 // replacement (when only a slow call is generated).
1701 call->set_req(TypeFunc::I_O, result_phi_i_o);
1702 }
1703 _igvn.replace_node(alloc, call);
1704 transform_later(call);
1705
1706 // Identify the output projections from the allocate node and
1707 // adjust any references to them.
1708 // The control and io projections look like:
1709 //
1710 // v---Proj(ctrl) <-----+ v---CatchProj(ctrl)
1711 // Allocate Catch
1712 // ^---Proj(io) <-------+ ^---CatchProj(io)
1713 //
1714 // We are interested in the CatchProj nodes.
1715 //
1716 extract_call_projections(call);
1717
1718 // An allocate node has separate memory projections for the uses on
1719 // the control and i_o paths. Replace the control memory projection with
1720 // result_phi_rawmem (unless we are only generating a slow call when
1721 // both memory projections are combined)
1722 if (!always_slow && _memproj_fallthrough != NULL) {
1723 for (DUIterator_Fast imax, i = _memproj_fallthrough->fast_outs(imax); i < imax; i++) {
1724 Node *use = _memproj_fallthrough->fast_out(i);
1725 _igvn.rehash_node_delayed(use);
1726 imax -= replace_input(use, _memproj_fallthrough, result_phi_rawmem);
1727 // back up iterator
1728 --i;
1729 }
1730 }
1731 // Now change uses of _memproj_catchall to use _memproj_fallthrough and delete
1732 // _memproj_catchall so we end up with a call that has only 1 memory projection.
1733 if (_memproj_catchall != NULL ) {
1734 if (_memproj_fallthrough == NULL) {
1735 _memproj_fallthrough = new ProjNode(call, TypeFunc::Memory);
1736 transform_later(_memproj_fallthrough);
1737 }
1738 for (DUIterator_Fast imax, i = _memproj_catchall->fast_outs(imax); i < imax; i++) {
1739 Node *use = _memproj_catchall->fast_out(i);
1740 _igvn.rehash_node_delayed(use);
1741 imax -= replace_input(use, _memproj_catchall, _memproj_fallthrough);
1742 // back up iterator
1743 --i;
1744 }
1745 assert(_memproj_catchall->outcnt() == 0, "all uses must be deleted");
1746 _igvn.remove_dead_node(_memproj_catchall);
1747 }
1748
1749 // An allocate node has separate i_o projections for the uses on the control
1750 // and i_o paths. Always replace the control i_o projection with result i_o
1751 // otherwise incoming i_o become dead when only a slow call is generated
1752 // (it is different from memory projections where both projections are
1753 // combined in such case).
1754 if (_ioproj_fallthrough != NULL) {
1755 for (DUIterator_Fast imax, i = _ioproj_fallthrough->fast_outs(imax); i < imax; i++) {
1756 Node *use = _ioproj_fallthrough->fast_out(i);
1757 _igvn.rehash_node_delayed(use);
1758 imax -= replace_input(use, _ioproj_fallthrough, result_phi_i_o);
1759 // back up iterator
1760 --i;
1761 }
1762 }
1763 // Now change uses of _ioproj_catchall to use _ioproj_fallthrough and delete
1764 // _ioproj_catchall so we end up with a call that has only 1 i_o projection.
1765 if (_ioproj_catchall != NULL ) {
1766 if (_ioproj_fallthrough == NULL) {
1767 _ioproj_fallthrough = new ProjNode(call, TypeFunc::I_O);
1768 transform_later(_ioproj_fallthrough);
1769 }
1770 for (DUIterator_Fast imax, i = _ioproj_catchall->fast_outs(imax); i < imax; i++) {
1771 Node *use = _ioproj_catchall->fast_out(i);
1772 _igvn.rehash_node_delayed(use);
1773 imax -= replace_input(use, _ioproj_catchall, _ioproj_fallthrough);
1774 // back up iterator
1775 --i;
1776 }
1777 assert(_ioproj_catchall->outcnt() == 0, "all uses must be deleted");
1778 _igvn.remove_dead_node(_ioproj_catchall);
1779 }
1780
1781 // if we generated only a slow call, we are done
1782 if (always_slow) {
1783 // Now we can unhook i_o.
1784 if (result_phi_i_o->outcnt() > 1) {
1785 call->set_req(TypeFunc::I_O, top());
1786 } else {
1787 assert(result_phi_i_o->unique_ctrl_out() == call, "");
1788 // Case of new array with negative size known during compilation.
1789 // AllocateArrayNode::Ideal() optimization disconnect unreachable
1790 // following code since call to runtime will throw exception.
1791 // As result there will be no users of i_o after the call.
1792 // Leave i_o attached to this call to avoid problems in preceding graph.
1793 }
1794 return;
1795 }
1796
1797
1798 if (_fallthroughcatchproj != NULL) {
1799 ctrl = _fallthroughcatchproj->clone();
1800 transform_later(ctrl);
1801 _igvn.replace_node(_fallthroughcatchproj, result_region);
1802 } else {
1803 ctrl = top();
1804 }
1805 Node *slow_result;
1806 if (_resproj == NULL) {
1807 // no uses of the allocation result
1808 slow_result = top();
1809 } else {
1810 slow_result = _resproj->clone();
1811 transform_later(slow_result);
1812 _igvn.replace_node(_resproj, result_phi_rawoop);
1813 }
1814
1815 // Plug slow-path into result merge point
1816 result_region ->init_req( slow_result_path, ctrl );
1817 result_phi_rawoop->init_req( slow_result_path, slow_result);
1818 result_phi_rawmem->init_req( slow_result_path, _memproj_fallthrough );
1819 transform_later(result_region);
1820 transform_later(result_phi_rawoop);
1821 transform_later(result_phi_rawmem);
1822 transform_later(result_phi_i_o);
1823 // This completes all paths into the result merge point
1824 }
1825
1826
1827 // Helper for PhaseMacroExpand::expand_allocate_common.
1828 // Initializes the newly-allocated storage.
1829 Node*
1830 PhaseMacroExpand::initialize_object(AllocateNode* alloc,
1831 Node* control, Node* rawmem, Node* object,
1832 Node* klass_node, Node* length,
1833 Node* size_in_bytes) {
1834 InitializeNode* init = alloc->initialization();
1835 // Store the klass & mark bits
1836 Node* mark_node = NULL;
1837 // For now only enable fast locking for non-array types
1838 if (UseBiasedLocking && (length == NULL)) {
1839 mark_node = make_load(control, rawmem, klass_node, in_bytes(Klass::prototype_header_offset()), TypeRawPtr::BOTTOM, T_ADDRESS);
1840 } else {
1841 mark_node = makecon(TypeRawPtr::make((address)markOopDesc::prototype()));
1842 }
1843 rawmem = make_store(control, rawmem, object, oopDesc::mark_offset_in_bytes(), mark_node, T_ADDRESS);
1844
1845 rawmem = make_store(control, rawmem, object, oopDesc::klass_offset_in_bytes(), klass_node, T_METADATA);
1846 int header_size = alloc->minimum_header_size(); // conservatively small
1847
1848 // Array length
1849 if (length != NULL) { // Arrays need length field
1850 rawmem = make_store(control, rawmem, object, arrayOopDesc::length_offset_in_bytes(), length, T_INT);
1851 // conservatively small header size:
1852 header_size = arrayOopDesc::base_offset_in_bytes(T_BYTE);
1853 ciKlass* k = _igvn.type(klass_node)->is_klassptr()->klass();
1854 if (k->is_array_klass()) // we know the exact header size in most cases:
1855 header_size = Klass::layout_helper_header_size(k->layout_helper());
1856 }
1857
1858 if (UseShenandoahGC) {
1859 // Initialize Shenandoah brooks pointer to point to the object itself.
1860 rawmem = make_store(control, rawmem, object, BrooksPointer::byte_offset(), object, T_OBJECT);
1861 }
1862
1863 // Clear the object body, if necessary.
1864 if (init == NULL) {
1865 // The init has somehow disappeared; be cautious and clear everything.
1866 //
1867 // This can happen if a node is allocated but an uncommon trap occurs
1868 // immediately. In this case, the Initialize gets associated with the
1869 // trap, and may be placed in a different (outer) loop, if the Allocate
1870 // is in a loop. If (this is rare) the inner loop gets unrolled, then
1871 // there can be two Allocates to one Initialize. The answer in all these
1872 // edge cases is safety first. It is always safe to clear immediately
1873 // within an Allocate, and then (maybe or maybe not) clear some more later.
1874 if (!(UseTLAB && ZeroTLAB)) {
1875 rawmem = ClearArrayNode::clear_memory(control, rawmem, object,
1876 header_size, size_in_bytes,
1877 &_igvn);
1878 }
1879 } else {
1880 if (!init->is_complete()) {
1881 // Try to win by zeroing only what the init does not store.
1882 // We can also try to do some peephole optimizations,
1883 // such as combining some adjacent subword stores.
1884 rawmem = init->complete_stores(control, rawmem, object,
1885 header_size, size_in_bytes, &_igvn);
1886 }
1887 // We have no more use for this link, since the AllocateNode goes away:
1888 init->set_req(InitializeNode::RawAddress, top());
1889 // (If we keep the link, it just confuses the register allocator,
1890 // who thinks he sees a real use of the address by the membar.)
1891 }
1892
1893 return rawmem;
1894 }
1895
1896 // Generate prefetch instructions for next allocations.
1897 Node* PhaseMacroExpand::prefetch_allocation(Node* i_o, Node*& needgc_false,
1898 Node*& contended_phi_rawmem,
1899 Node* old_eden_top, Node* new_eden_top,
1900 Node* length) {
1901 enum { fall_in_path = 1, pf_path = 2 };
1902 if( UseTLAB && AllocatePrefetchStyle == 2 ) {
1903 // Generate prefetch allocation with watermark check.
1904 // As an allocation hits the watermark, we will prefetch starting
1905 // at a "distance" away from watermark.
1906
1907 Node *pf_region = new RegionNode(3);
1908 Node *pf_phi_rawmem = new PhiNode( pf_region, Type::MEMORY,
1909 TypeRawPtr::BOTTOM );
1910 // I/O is used for Prefetch
1911 Node *pf_phi_abio = new PhiNode( pf_region, Type::ABIO );
1912
1913 Node *thread = new ThreadLocalNode();
1914 transform_later(thread);
1915
1916 Node *eden_pf_adr = new AddPNode( top()/*not oop*/, thread,
1917 _igvn.MakeConX(in_bytes(JavaThread::tlab_pf_top_offset())) );
1918 transform_later(eden_pf_adr);
1919
1920 Node *old_pf_wm = new LoadPNode(needgc_false,
1921 contended_phi_rawmem, eden_pf_adr,
1922 TypeRawPtr::BOTTOM, TypeRawPtr::BOTTOM,
1923 MemNode::unordered);
1924 transform_later(old_pf_wm);
1925
1926 // check against new_eden_top
1927 Node *need_pf_cmp = new CmpPNode( new_eden_top, old_pf_wm );
1928 transform_later(need_pf_cmp);
1929 Node *need_pf_bol = new BoolNode( need_pf_cmp, BoolTest::ge );
1930 transform_later(need_pf_bol);
1931 IfNode *need_pf_iff = new IfNode( needgc_false, need_pf_bol,
1932 PROB_UNLIKELY_MAG(4), COUNT_UNKNOWN );
1933 transform_later(need_pf_iff);
1934
1935 // true node, add prefetchdistance
1936 Node *need_pf_true = new IfTrueNode( need_pf_iff );
1937 transform_later(need_pf_true);
1938
1939 Node *need_pf_false = new IfFalseNode( need_pf_iff );
1940 transform_later(need_pf_false);
1941
1942 Node *new_pf_wmt = new AddPNode( top(), old_pf_wm,
1943 _igvn.MakeConX(AllocatePrefetchDistance) );
1944 transform_later(new_pf_wmt );
1945 new_pf_wmt->set_req(0, need_pf_true);
1946
1947 Node *store_new_wmt = new StorePNode(need_pf_true,
1948 contended_phi_rawmem, eden_pf_adr,
1949 TypeRawPtr::BOTTOM, new_pf_wmt,
1950 MemNode::unordered);
1951 transform_later(store_new_wmt);
1952
1953 // adding prefetches
1954 pf_phi_abio->init_req( fall_in_path, i_o );
1955
1956 Node *prefetch_adr;
1957 Node *prefetch;
1958 uint lines = (length != NULL) ? AllocatePrefetchLines : AllocateInstancePrefetchLines;
1959 uint step_size = AllocatePrefetchStepSize;
1960 uint distance = 0;
1961
1962 for ( uint i = 0; i < lines; i++ ) {
1963 prefetch_adr = new AddPNode( old_pf_wm, new_pf_wmt,
1964 _igvn.MakeConX(distance) );
1965 transform_later(prefetch_adr);
1966 prefetch = new PrefetchAllocationNode( i_o, prefetch_adr );
1967 transform_later(prefetch);
1968 distance += step_size;
1969 i_o = prefetch;
1970 }
1971 pf_phi_abio->set_req( pf_path, i_o );
1972
1973 pf_region->init_req( fall_in_path, need_pf_false );
1974 pf_region->init_req( pf_path, need_pf_true );
1975
1976 pf_phi_rawmem->init_req( fall_in_path, contended_phi_rawmem );
1977 pf_phi_rawmem->init_req( pf_path, store_new_wmt );
1978
1979 transform_later(pf_region);
1980 transform_later(pf_phi_rawmem);
1981 transform_later(pf_phi_abio);
1982
1983 needgc_false = pf_region;
1984 contended_phi_rawmem = pf_phi_rawmem;
1985 i_o = pf_phi_abio;
1986 } else if( UseTLAB && AllocatePrefetchStyle == 3 ) {
1987 // Insert a prefetch instruction for each allocation.
1988 // This code is used to generate 1 prefetch instruction per cache line.
1989
1990 // Generate several prefetch instructions.
1991 uint lines = (length != NULL) ? AllocatePrefetchLines : AllocateInstancePrefetchLines;
1992 uint step_size = AllocatePrefetchStepSize;
1993 uint distance = AllocatePrefetchDistance;
1994
1995 // Next cache address.
1996 Node *cache_adr = new AddPNode(old_eden_top, old_eden_top,
1997 _igvn.MakeConX(step_size + distance));
1998 transform_later(cache_adr);
1999 cache_adr = new CastP2XNode(needgc_false, cache_adr);
2000 transform_later(cache_adr);
2001 // Address is aligned to execute prefetch to the beginning of cache line size
2002 // (it is important when BIS instruction is used on SPARC as prefetch).
2003 Node* mask = _igvn.MakeConX(~(intptr_t)(step_size-1));
2004 cache_adr = new AndXNode(cache_adr, mask);
2005 transform_later(cache_adr);
2006 cache_adr = new CastX2PNode(cache_adr);
2007 transform_later(cache_adr);
2008
2009 // Prefetch
2010 Node *prefetch = new PrefetchAllocationNode( contended_phi_rawmem, cache_adr );
2011 prefetch->set_req(0, needgc_false);
2012 transform_later(prefetch);
2013 contended_phi_rawmem = prefetch;
2014 Node *prefetch_adr;
2015 distance = step_size;
2016 for ( uint i = 1; i < lines; i++ ) {
2017 prefetch_adr = new AddPNode( cache_adr, cache_adr,
2018 _igvn.MakeConX(distance) );
2019 transform_later(prefetch_adr);
2020 prefetch = new PrefetchAllocationNode( contended_phi_rawmem, prefetch_adr );
2021 transform_later(prefetch);
2022 distance += step_size;
2023 contended_phi_rawmem = prefetch;
2024 }
2025 } else if( AllocatePrefetchStyle > 0 ) {
2026 // Insert a prefetch for each allocation only on the fast-path
2027 Node *prefetch_adr;
2028 Node *prefetch;
2029 // Generate several prefetch instructions.
2030 uint lines = (length != NULL) ? AllocatePrefetchLines : AllocateInstancePrefetchLines;
2031 uint step_size = AllocatePrefetchStepSize;
2032 uint distance = AllocatePrefetchDistance;
2033 for ( uint i = 0; i < lines; i++ ) {
2034 prefetch_adr = new AddPNode( old_eden_top, new_eden_top,
2035 _igvn.MakeConX(distance) );
2036 transform_later(prefetch_adr);
2037 prefetch = new PrefetchAllocationNode( i_o, prefetch_adr );
2038 // Do not let it float too high, since if eden_top == eden_end,
2039 // both might be null.
2040 if( i == 0 ) { // Set control for first prefetch, next follows it
2041 prefetch->init_req(0, needgc_false);
2042 }
2043 transform_later(prefetch);
2044 distance += step_size;
2045 i_o = prefetch;
2046 }
2047 }
2048 return i_o;
2049 }
2050
2051
2052 void PhaseMacroExpand::expand_allocate(AllocateNode *alloc) {
2053 expand_allocate_common(alloc, NULL,
2054 OptoRuntime::new_instance_Type(),
2055 OptoRuntime::new_instance_Java());
2056 }
2057
2058 void PhaseMacroExpand::expand_allocate_array(AllocateArrayNode *alloc) {
2059 Node* length = alloc->in(AllocateNode::ALength);
2060 InitializeNode* init = alloc->initialization();
2061 Node* klass_node = alloc->in(AllocateNode::KlassNode);
2062 ciKlass* k = _igvn.type(klass_node)->is_klassptr()->klass();
2063 address slow_call_address; // Address of slow call
2064 if (init != NULL && init->is_complete_with_arraycopy() &&
2065 k->is_type_array_klass()) {
2066 // Don't zero type array during slow allocation in VM since
2067 // it will be initialized later by arraycopy in compiled code.
2068 slow_call_address = OptoRuntime::new_array_nozero_Java();
2069 } else {
2070 slow_call_address = OptoRuntime::new_array_Java();
2071 }
2072 expand_allocate_common(alloc, length,
2073 OptoRuntime::new_array_Type(),
2074 slow_call_address);
2075 }
2076
2077 //-------------------mark_eliminated_box----------------------------------
2078 //
2079 // During EA obj may point to several objects but after few ideal graph
2080 // transformations (CCP) it may point to only one non escaping object
2081 // (but still using phi), corresponding locks and unlocks will be marked
2082 // for elimination. Later obj could be replaced with a new node (new phi)
2083 // and which does not have escape information. And later after some graph
2084 // reshape other locks and unlocks (which were not marked for elimination
2085 // before) are connected to this new obj (phi) but they still will not be
2086 // marked for elimination since new obj has no escape information.
2087 // Mark all associated (same box and obj) lock and unlock nodes for
2088 // elimination if some of them marked already.
2089 void PhaseMacroExpand::mark_eliminated_box(Node* oldbox, Node* obj) {
2090 if (oldbox->as_BoxLock()->is_eliminated())
2091 return; // This BoxLock node was processed already.
2092
2093 // New implementation (EliminateNestedLocks) has separate BoxLock
2094 // node for each locked region so mark all associated locks/unlocks as
2095 // eliminated even if different objects are referenced in one locked region
2096 // (for example, OSR compilation of nested loop inside locked scope).
2097 if (EliminateNestedLocks ||
2098 oldbox->as_BoxLock()->is_simple_lock_region(NULL, obj)) {
2099 // Box is used only in one lock region. Mark this box as eliminated.
2100 _igvn.hash_delete(oldbox);
2101 oldbox->as_BoxLock()->set_eliminated(); // This changes box's hash value
2102 _igvn.hash_insert(oldbox);
2103
2104 for (uint i = 0; i < oldbox->outcnt(); i++) {
2105 Node* u = oldbox->raw_out(i);
2106 if (u->is_AbstractLock() && !u->as_AbstractLock()->is_non_esc_obj()) {
2107 AbstractLockNode* alock = u->as_AbstractLock();
2108 // Check lock's box since box could be referenced by Lock's debug info.
2109 if (alock->box_node() == oldbox) {
2110 // Mark eliminated all related locks and unlocks.
2111 #ifdef ASSERT
2112 alock->log_lock_optimization(C, "eliminate_lock_set_non_esc4");
2113 #endif
2114 alock->set_non_esc_obj();
2115 }
2116 }
2117 }
2118 return;
2119 }
2120
2121 // Create new "eliminated" BoxLock node and use it in monitor debug info
2122 // instead of oldbox for the same object.
2123 BoxLockNode* newbox = oldbox->clone()->as_BoxLock();
2124
2125 // Note: BoxLock node is marked eliminated only here and it is used
2126 // to indicate that all associated lock and unlock nodes are marked
2127 // for elimination.
2128 newbox->set_eliminated();
2129 transform_later(newbox);
2130
2131 // Replace old box node with new box for all users of the same object.
2132 for (uint i = 0; i < oldbox->outcnt();) {
2133 bool next_edge = true;
2134
2135 Node* u = oldbox->raw_out(i);
2136 if (u->is_AbstractLock()) {
2137 AbstractLockNode* alock = u->as_AbstractLock();
2138 if (alock->box_node() == oldbox && alock->obj_node()->eqv_uncast(obj)) {
2139 // Replace Box and mark eliminated all related locks and unlocks.
2140 #ifdef ASSERT
2141 alock->log_lock_optimization(C, "eliminate_lock_set_non_esc5");
2142 #endif
2143 alock->set_non_esc_obj();
2144 _igvn.rehash_node_delayed(alock);
2145 alock->set_box_node(newbox);
2146 next_edge = false;
2147 }
2148 }
2149 if (u->is_FastLock() && u->as_FastLock()->obj_node()->eqv_uncast(obj)) {
2150 FastLockNode* flock = u->as_FastLock();
2151 assert(flock->box_node() == oldbox, "sanity");
2152 _igvn.rehash_node_delayed(flock);
2153 flock->set_box_node(newbox);
2154 next_edge = false;
2155 }
2156
2157 // Replace old box in monitor debug info.
2158 if (u->is_SafePoint() && u->as_SafePoint()->jvms()) {
2159 SafePointNode* sfn = u->as_SafePoint();
2160 JVMState* youngest_jvms = sfn->jvms();
2161 int max_depth = youngest_jvms->depth();
2162 for (int depth = 1; depth <= max_depth; depth++) {
2163 JVMState* jvms = youngest_jvms->of_depth(depth);
2164 int num_mon = jvms->nof_monitors();
2165 // Loop over monitors
2166 for (int idx = 0; idx < num_mon; idx++) {
2167 Node* obj_node = sfn->monitor_obj(jvms, idx);
2168 Node* box_node = sfn->monitor_box(jvms, idx);
2169 if (box_node == oldbox && obj_node->eqv_uncast(obj)) {
2170 int j = jvms->monitor_box_offset(idx);
2171 _igvn.replace_input_of(u, j, newbox);
2172 next_edge = false;
2173 }
2174 }
2175 }
2176 }
2177 if (next_edge) i++;
2178 }
2179 }
2180
2181 //-----------------------mark_eliminated_locking_nodes-----------------------
2182 void PhaseMacroExpand::mark_eliminated_locking_nodes(AbstractLockNode *alock) {
2183 if (EliminateNestedLocks) {
2184 if (alock->is_nested()) {
2185 assert(alock->box_node()->as_BoxLock()->is_eliminated(), "sanity");
2186 return;
2187 } else if (!alock->is_non_esc_obj()) { // Not eliminated or coarsened
2188 // Only Lock node has JVMState needed here.
2189 // Not that preceding claim is documented anywhere else.
2190 if (alock->jvms() != NULL) {
2191 if (alock->as_Lock()->is_nested_lock_region()) {
2192 // Mark eliminated related nested locks and unlocks.
2193 Node* obj = alock->obj_node();
2194 BoxLockNode* box_node = alock->box_node()->as_BoxLock();
2195 assert(!box_node->is_eliminated(), "should not be marked yet");
2196 // Note: BoxLock node is marked eliminated only here
2197 // and it is used to indicate that all associated lock
2198 // and unlock nodes are marked for elimination.
2199 box_node->set_eliminated(); // Box's hash is always NO_HASH here
2200 for (uint i = 0; i < box_node->outcnt(); i++) {
2201 Node* u = box_node->raw_out(i);
2202 if (u->is_AbstractLock()) {
2203 alock = u->as_AbstractLock();
2204 if (alock->box_node() == box_node) {
2205 // Verify that this Box is referenced only by related locks.
2206 assert(alock->obj_node()->eqv_uncast(obj), "");
2207 // Mark all related locks and unlocks.
2208 #ifdef ASSERT
2209 alock->log_lock_optimization(C, "eliminate_lock_set_nested");
2210 #endif
2211 alock->set_nested();
2212 }
2213 }
2214 }
2215 } else {
2216 #ifdef ASSERT
2217 alock->log_lock_optimization(C, "eliminate_lock_NOT_nested_lock_region");
2218 if (C->log() != NULL)
2219 alock->as_Lock()->is_nested_lock_region(C); // rerun for debugging output
2220 #endif
2221 }
2222 }
2223 return;
2224 }
2225 // Process locks for non escaping object
2226 assert(alock->is_non_esc_obj(), "");
2227 } // EliminateNestedLocks
2228
2229 if (alock->is_non_esc_obj()) { // Lock is used for non escaping object
2230 // Look for all locks of this object and mark them and
2231 // corresponding BoxLock nodes as eliminated.
2232 Node* obj = alock->obj_node();
2233 for (uint j = 0; j < obj->outcnt(); j++) {
2234 Node* o = obj->raw_out(j);
2235 if (o->is_AbstractLock() &&
2236 o->as_AbstractLock()->obj_node()->eqv_uncast(obj)) {
2237 alock = o->as_AbstractLock();
2238 Node* box = alock->box_node();
2239 // Replace old box node with new eliminated box for all users
2240 // of the same object and mark related locks as eliminated.
2241 mark_eliminated_box(box, obj);
2242 }
2243 }
2244 }
2245 }
2246
2247 // we have determined that this lock/unlock can be eliminated, we simply
2248 // eliminate the node without expanding it.
2249 //
2250 // Note: The membar's associated with the lock/unlock are currently not
2251 // eliminated. This should be investigated as a future enhancement.
2252 //
2253 bool PhaseMacroExpand::eliminate_locking_node(AbstractLockNode *alock) {
2254
2255 if (!alock->is_eliminated()) {
2256 return false;
2257 }
2258 #ifdef ASSERT
2259 if (!alock->is_coarsened()) {
2260 // Check that new "eliminated" BoxLock node is created.
2261 BoxLockNode* oldbox = alock->box_node()->as_BoxLock();
2262 assert(oldbox->is_eliminated(), "should be done already");
2263 }
2264 #endif
2265
2266 alock->log_lock_optimization(C, "eliminate_lock");
2267
2268 #ifndef PRODUCT
2269 if (PrintEliminateLocks) {
2270 if (alock->is_Lock()) {
2271 tty->print_cr("++++ Eliminated: %d Lock", alock->_idx);
2272 } else {
2273 tty->print_cr("++++ Eliminated: %d Unlock", alock->_idx);
2274 }
2275 }
2276 #endif
2277
2278 Node* mem = alock->in(TypeFunc::Memory);
2279 Node* ctrl = alock->in(TypeFunc::Control);
2280
2281 extract_call_projections(alock);
2282 // There are 2 projections from the lock. The lock node will
2283 // be deleted when its last use is subsumed below.
2284 assert(alock->outcnt() == 2 &&
2285 _fallthroughproj != NULL &&
2286 _memproj_fallthrough != NULL,
2287 "Unexpected projections from Lock/Unlock");
2288
2289 Node* fallthroughproj = _fallthroughproj;
2290 Node* memproj_fallthrough = _memproj_fallthrough;
2291
2292 // The memory projection from a lock/unlock is RawMem
2293 // The input to a Lock is merged memory, so extract its RawMem input
2294 // (unless the MergeMem has been optimized away.)
2295 if (alock->is_Lock()) {
2296 // Seach for MemBarAcquireLock node and delete it also.
2297 MemBarNode* membar = fallthroughproj->unique_ctrl_out()->as_MemBar();
2298 assert(membar != NULL && membar->Opcode() == Op_MemBarAcquireLock, "");
2299 Node* ctrlproj = membar->proj_out(TypeFunc::Control);
2300 Node* memproj = membar->proj_out(TypeFunc::Memory);
2301 _igvn.replace_node(ctrlproj, fallthroughproj);
2302 _igvn.replace_node(memproj, memproj_fallthrough);
2303
2304 // Delete FastLock node also if this Lock node is unique user
2305 // (a loop peeling may clone a Lock node).
2306 Node* flock = alock->as_Lock()->fastlock_node();
2307 if (flock->outcnt() == 1) {
2308 assert(flock->unique_out() == alock, "sanity");
2309 _igvn.replace_node(flock, top());
2310 }
2311 }
2312
2313 // Seach for MemBarReleaseLock node and delete it also.
2314 if (alock->is_Unlock() && ctrl != NULL && ctrl->is_Proj() &&
2315 ctrl->in(0)->is_MemBar()) {
2316 MemBarNode* membar = ctrl->in(0)->as_MemBar();
2317 assert(membar->Opcode() == Op_MemBarReleaseLock &&
2318 mem->is_Proj() && membar == mem->in(0), "");
2319 _igvn.replace_node(fallthroughproj, ctrl);
2320 _igvn.replace_node(memproj_fallthrough, mem);
2321 fallthroughproj = ctrl;
2322 memproj_fallthrough = mem;
2323 ctrl = membar->in(TypeFunc::Control);
2324 mem = membar->in(TypeFunc::Memory);
2325 }
2326
2327 _igvn.replace_node(fallthroughproj, ctrl);
2328 _igvn.replace_node(memproj_fallthrough, mem);
2329 return true;
2330 }
2331
2332
2333 //------------------------------expand_lock_node----------------------
2334 void PhaseMacroExpand::expand_lock_node(LockNode *lock) {
2335
2336 Node* ctrl = lock->in(TypeFunc::Control);
2337 Node* mem = lock->in(TypeFunc::Memory);
2338 Node* obj = lock->obj_node();
2339 Node* box = lock->box_node();
2340 Node* flock = lock->fastlock_node();
2341
2342 assert(!box->as_BoxLock()->is_eliminated(), "sanity");
2343
2344 // Make the merge point
2345 Node *region;
2346 Node *mem_phi;
2347 Node *slow_path;
2348
2349 if (UseOptoBiasInlining) {
2350 /*
2351 * See the full description in MacroAssembler::biased_locking_enter().
2352 *
2353 * if( (mark_word & biased_lock_mask) == biased_lock_pattern ) {
2354 * // The object is biased.
2355 * proto_node = klass->prototype_header;
2356 * o_node = thread | proto_node;
2357 * x_node = o_node ^ mark_word;
2358 * if( (x_node & ~age_mask) == 0 ) { // Biased to the current thread ?
2359 * // Done.
2360 * } else {
2361 * if( (x_node & biased_lock_mask) != 0 ) {
2362 * // The klass's prototype header is no longer biased.
2363 * cas(&mark_word, mark_word, proto_node)
2364 * goto cas_lock;
2365 * } else {
2366 * // The klass's prototype header is still biased.
2367 * if( (x_node & epoch_mask) != 0 ) { // Expired epoch?
2368 * old = mark_word;
2369 * new = o_node;
2370 * } else {
2371 * // Different thread or anonymous biased.
2372 * old = mark_word & (epoch_mask | age_mask | biased_lock_mask);
2373 * new = thread | old;
2374 * }
2375 * // Try to rebias.
2376 * if( cas(&mark_word, old, new) == 0 ) {
2377 * // Done.
2378 * } else {
2379 * goto slow_path; // Failed.
2380 * }
2381 * }
2382 * }
2383 * } else {
2384 * // The object is not biased.
2385 * cas_lock:
2386 * if( FastLock(obj) == 0 ) {
2387 * // Done.
2388 * } else {
2389 * slow_path:
2390 * OptoRuntime::complete_monitor_locking_Java(obj);
2391 * }
2392 * }
2393 */
2394
2395 region = new RegionNode(5);
2396 // create a Phi for the memory state
2397 mem_phi = new PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM);
2398
2399 Node* fast_lock_region = new RegionNode(3);
2400 Node* fast_lock_mem_phi = new PhiNode( fast_lock_region, Type::MEMORY, TypeRawPtr::BOTTOM);
2401
2402 // First, check mark word for the biased lock pattern.
2403 Node* mark_node = make_load(ctrl, mem, obj, oopDesc::mark_offset_in_bytes(), TypeX_X, TypeX_X->basic_type());
2404
2405 // Get fast path - mark word has the biased lock pattern.
2406 ctrl = opt_bits_test(ctrl, fast_lock_region, 1, mark_node,
2407 markOopDesc::biased_lock_mask_in_place,
2408 markOopDesc::biased_lock_pattern, true);
2409 // fast_lock_region->in(1) is set to slow path.
2410 fast_lock_mem_phi->init_req(1, mem);
2411
2412 // Now check that the lock is biased to the current thread and has
2413 // the same epoch and bias as Klass::_prototype_header.
2414
2415 // Special-case a fresh allocation to avoid building nodes:
2416 Node* klass_node = AllocateNode::Ideal_klass(obj, &_igvn);
2417 if (klass_node == NULL) {
2418 Node* k_adr = basic_plus_adr(obj, oopDesc::klass_offset_in_bytes());
2419 klass_node = transform_later(LoadKlassNode::make(_igvn, NULL, mem, k_adr, _igvn.type(k_adr)->is_ptr()));
2420 #ifdef _LP64
2421 if (UseCompressedClassPointers && klass_node->is_DecodeNKlass()) {
2422 assert(klass_node->in(1)->Opcode() == Op_LoadNKlass, "sanity");
2423 klass_node->in(1)->init_req(0, ctrl);
2424 } else
2425 #endif
2426 klass_node->init_req(0, ctrl);
2427 }
2428 Node *proto_node = make_load(ctrl, mem, klass_node, in_bytes(Klass::prototype_header_offset()), TypeX_X, TypeX_X->basic_type());
2429
2430 Node* thread = transform_later(new ThreadLocalNode());
2431 Node* cast_thread = transform_later(new CastP2XNode(ctrl, thread));
2432 Node* o_node = transform_later(new OrXNode(cast_thread, proto_node));
2433 Node* x_node = transform_later(new XorXNode(o_node, mark_node));
2434
2435 // Get slow path - mark word does NOT match the value.
2436 Node* not_biased_ctrl = opt_bits_test(ctrl, region, 3, x_node,
2437 (~markOopDesc::age_mask_in_place), 0);
2438 // region->in(3) is set to fast path - the object is biased to the current thread.
2439 mem_phi->init_req(3, mem);
2440
2441
2442 // Mark word does NOT match the value (thread | Klass::_prototype_header).
2443
2444
2445 // First, check biased pattern.
2446 // Get fast path - _prototype_header has the same biased lock pattern.
2447 ctrl = opt_bits_test(not_biased_ctrl, fast_lock_region, 2, x_node,
2448 markOopDesc::biased_lock_mask_in_place, 0, true);
2449
2450 not_biased_ctrl = fast_lock_region->in(2); // Slow path
2451 // fast_lock_region->in(2) - the prototype header is no longer biased
2452 // and we have to revoke the bias on this object.
2453 // We are going to try to reset the mark of this object to the prototype
2454 // value and fall through to the CAS-based locking scheme.
2455 Node* adr = basic_plus_adr(obj, oopDesc::mark_offset_in_bytes());
2456 Node* cas = new StoreXConditionalNode(not_biased_ctrl, mem, adr,
2457 proto_node, mark_node);
2458 transform_later(cas);
2459 Node* proj = transform_later(new SCMemProjNode(cas));
2460 fast_lock_mem_phi->init_req(2, proj);
2461
2462
2463 // Second, check epoch bits.
2464 Node* rebiased_region = new RegionNode(3);
2465 Node* old_phi = new PhiNode( rebiased_region, TypeX_X);
2466 Node* new_phi = new PhiNode( rebiased_region, TypeX_X);
2467
2468 // Get slow path - mark word does NOT match epoch bits.
2469 Node* epoch_ctrl = opt_bits_test(ctrl, rebiased_region, 1, x_node,
2470 markOopDesc::epoch_mask_in_place, 0);
2471 // The epoch of the current bias is not valid, attempt to rebias the object
2472 // toward the current thread.
2473 rebiased_region->init_req(2, epoch_ctrl);
2474 old_phi->init_req(2, mark_node);
2475 new_phi->init_req(2, o_node);
2476
2477 // rebiased_region->in(1) is set to fast path.
2478 // The epoch of the current bias is still valid but we know
2479 // nothing about the owner; it might be set or it might be clear.
2480 Node* cmask = MakeConX(markOopDesc::biased_lock_mask_in_place |
2481 markOopDesc::age_mask_in_place |
2482 markOopDesc::epoch_mask_in_place);
2483 Node* old = transform_later(new AndXNode(mark_node, cmask));
2484 cast_thread = transform_later(new CastP2XNode(ctrl, thread));
2485 Node* new_mark = transform_later(new OrXNode(cast_thread, old));
2486 old_phi->init_req(1, old);
2487 new_phi->init_req(1, new_mark);
2488
2489 transform_later(rebiased_region);
2490 transform_later(old_phi);
2491 transform_later(new_phi);
2492
2493 // Try to acquire the bias of the object using an atomic operation.
2494 // If this fails we will go in to the runtime to revoke the object's bias.
2495 cas = new StoreXConditionalNode(rebiased_region, mem, adr, new_phi, old_phi);
2496 transform_later(cas);
2497 proj = transform_later(new SCMemProjNode(cas));
2498
2499 // Get slow path - Failed to CAS.
2500 not_biased_ctrl = opt_bits_test(rebiased_region, region, 4, cas, 0, 0);
2501 mem_phi->init_req(4, proj);
2502 // region->in(4) is set to fast path - the object is rebiased to the current thread.
2503
2504 // Failed to CAS.
2505 slow_path = new RegionNode(3);
2506 Node *slow_mem = new PhiNode( slow_path, Type::MEMORY, TypeRawPtr::BOTTOM);
2507
2508 slow_path->init_req(1, not_biased_ctrl); // Capture slow-control
2509 slow_mem->init_req(1, proj);
2510
2511 // Call CAS-based locking scheme (FastLock node).
2512
2513 transform_later(fast_lock_region);
2514 transform_later(fast_lock_mem_phi);
2515
2516 // Get slow path - FastLock failed to lock the object.
2517 ctrl = opt_bits_test(fast_lock_region, region, 2, flock, 0, 0);
2518 mem_phi->init_req(2, fast_lock_mem_phi);
2519 // region->in(2) is set to fast path - the object is locked to the current thread.
2520
2521 slow_path->init_req(2, ctrl); // Capture slow-control
2522 slow_mem->init_req(2, fast_lock_mem_phi);
2523
2524 transform_later(slow_path);
2525 transform_later(slow_mem);
2526 // Reset lock's memory edge.
2527 lock->set_req(TypeFunc::Memory, slow_mem);
2528
2529 } else {
2530 region = new RegionNode(3);
2531 // create a Phi for the memory state
2532 mem_phi = new PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM);
2533
2534 // Optimize test; set region slot 2
2535 slow_path = opt_bits_test(ctrl, region, 2, flock, 0, 0);
2536 mem_phi->init_req(2, mem);
2537 }
2538
2539 // Make slow path call
2540 CallNode *call = make_slow_call((CallNode *) lock, OptoRuntime::complete_monitor_enter_Type(),
2541 OptoRuntime::complete_monitor_locking_Java(), NULL, slow_path,
2542 obj, box, NULL);
2543
2544 extract_call_projections(call);
2545
2546 // Slow path can only throw asynchronous exceptions, which are always
2547 // de-opted. So the compiler thinks the slow-call can never throw an
2548 // exception. If it DOES throw an exception we would need the debug
2549 // info removed first (since if it throws there is no monitor).
2550 assert ( _ioproj_fallthrough == NULL && _ioproj_catchall == NULL &&
2551 _memproj_catchall == NULL && _catchallcatchproj == NULL, "Unexpected projection from Lock");
2552
2553 // Capture slow path
2554 // disconnect fall-through projection from call and create a new one
2555 // hook up users of fall-through projection to region
2556 Node *slow_ctrl = _fallthroughproj->clone();
2557 transform_later(slow_ctrl);
2558 _igvn.hash_delete(_fallthroughproj);
2559 _fallthroughproj->disconnect_inputs(NULL, C);
2560 region->init_req(1, slow_ctrl);
2561 // region inputs are now complete
2562 transform_later(region);
2563 _igvn.replace_node(_fallthroughproj, region);
2564
2565 Node *memproj = transform_later(new ProjNode(call, TypeFunc::Memory));
2566 mem_phi->init_req(1, memproj );
2567 transform_later(mem_phi);
2568 _igvn.replace_node(_memproj_fallthrough, mem_phi);
2569 }
2570
2571 //------------------------------expand_unlock_node----------------------
2572 void PhaseMacroExpand::expand_unlock_node(UnlockNode *unlock) {
2573
2574 Node* ctrl = unlock->in(TypeFunc::Control);
2575 Node* mem = unlock->in(TypeFunc::Memory);
2576 Node* obj = unlock->obj_node();
2577 Node* box = unlock->box_node();
2578
2579 assert(!box->as_BoxLock()->is_eliminated(), "sanity");
2580
2581 // No need for a null check on unlock
2582
2583 // Make the merge point
2584 Node *region;
2585 Node *mem_phi;
2586
2587 if (UseOptoBiasInlining) {
2588 // Check for biased locking unlock case, which is a no-op.
2589 // See the full description in MacroAssembler::biased_locking_exit().
2590 region = new RegionNode(4);
2591 // create a Phi for the memory state
2592 mem_phi = new PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM);
2593 mem_phi->init_req(3, mem);
2594
2595 Node* mark_node = make_load(ctrl, mem, obj, oopDesc::mark_offset_in_bytes(), TypeX_X, TypeX_X->basic_type());
2596 ctrl = opt_bits_test(ctrl, region, 3, mark_node,
2597 markOopDesc::biased_lock_mask_in_place,
2598 markOopDesc::biased_lock_pattern);
2599 } else {
2600 region = new RegionNode(3);
2601 // create a Phi for the memory state
2602 mem_phi = new PhiNode( region, Type::MEMORY, TypeRawPtr::BOTTOM);
2603 }
2604
2605 FastUnlockNode *funlock = new FastUnlockNode( ctrl, obj, box );
2606 funlock = transform_later( funlock )->as_FastUnlock();
2607 // Optimize test; set region slot 2
2608 Node *slow_path = opt_bits_test(ctrl, region, 2, funlock, 0, 0);
2609 Node *thread = transform_later(new ThreadLocalNode());
2610
2611 CallNode *call = make_slow_call((CallNode *) unlock, OptoRuntime::complete_monitor_exit_Type(),
2612 CAST_FROM_FN_PTR(address, SharedRuntime::complete_monitor_unlocking_C),
2613 "complete_monitor_unlocking_C", slow_path, obj, box, thread);
2614
2615 extract_call_projections(call);
2616
2617 assert ( _ioproj_fallthrough == NULL && _ioproj_catchall == NULL &&
2618 _memproj_catchall == NULL && _catchallcatchproj == NULL, "Unexpected projection from Lock");
2619
2620 // No exceptions for unlocking
2621 // Capture slow path
2622 // disconnect fall-through projection from call and create a new one
2623 // hook up users of fall-through projection to region
2624 Node *slow_ctrl = _fallthroughproj->clone();
2625 transform_later(slow_ctrl);
2626 _igvn.hash_delete(_fallthroughproj);
2627 _fallthroughproj->disconnect_inputs(NULL, C);
2628 region->init_req(1, slow_ctrl);
2629 // region inputs are now complete
2630 transform_later(region);
2631 _igvn.replace_node(_fallthroughproj, region);
2632
2633 Node *memproj = transform_later(new ProjNode(call, TypeFunc::Memory) );
2634 mem_phi->init_req(1, memproj );
2635 mem_phi->init_req(2, mem);
2636 transform_later(mem_phi);
2637 _igvn.replace_node(_memproj_fallthrough, mem_phi);
2638 }
2639
2640 //---------------------------eliminate_macro_nodes----------------------
2641 // Eliminate scalar replaced allocations and associated locks.
2642 void PhaseMacroExpand::eliminate_macro_nodes() {
2643 if (C->macro_count() == 0)
2644 return;
2645
2646 // First, attempt to eliminate locks
2647 int cnt = C->macro_count();
2648 for (int i=0; i < cnt; i++) {
2649 Node *n = C->macro_node(i);
2650 if (n->is_AbstractLock()) { // Lock and Unlock nodes
2651 // Before elimination mark all associated (same box and obj)
2652 // lock and unlock nodes.
2653 mark_eliminated_locking_nodes(n->as_AbstractLock());
2654 }
2655 }
2656 bool progress = true;
2657 while (progress) {
2658 progress = false;
2659 for (int i = C->macro_count(); i > 0; i--) {
2660 Node * n = C->macro_node(i-1);
2661 bool success = false;
2662 debug_only(int old_macro_count = C->macro_count(););
2663 if (n->is_AbstractLock()) {
2664 success = eliminate_locking_node(n->as_AbstractLock());
2665 }
2666 assert(success == (C->macro_count() < old_macro_count), "elimination reduces macro count");
2667 progress = progress || success;
2668 }
2669 }
2670 // Next, attempt to eliminate allocations
2671 _has_locks = false;
2672 progress = true;
2673 while (progress) {
2674 progress = false;
2675 for (int i = C->macro_count(); i > 0; i--) {
2676 Node * n = C->macro_node(i-1);
2677 bool success = false;
2678 debug_only(int old_macro_count = C->macro_count(););
2679 switch (n->class_id()) {
2680 case Node::Class_Allocate:
2681 case Node::Class_AllocateArray:
2682 success = eliminate_allocate_node(n->as_Allocate());
2683 break;
2684 case Node::Class_CallStaticJava:
2685 success = eliminate_boxing_node(n->as_CallStaticJava());
2686 break;
2687 case Node::Class_Lock:
2688 case Node::Class_Unlock:
2689 assert(!n->as_AbstractLock()->is_eliminated(), "sanity");
2690 _has_locks = true;
2691 break;
2692 case Node::Class_ArrayCopy:
2693 break;
2694 default:
2695 assert(n->Opcode() == Op_LoopLimit ||
2696 n->Opcode() == Op_Opaque1 ||
2697 n->Opcode() == Op_Opaque2 ||
2698 n->Opcode() == Op_Opaque3 ||
2699 n->Opcode() == Op_Opaque4, "unknown node type in macro list");
2700 }
2701 assert(success == (C->macro_count() < old_macro_count), "elimination reduces macro count");
2702 progress = progress || success;
2703 }
2704 }
2705 }
2706
2707 //------------------------------expand_macro_nodes----------------------
2708 // Returns true if a failure occurred.
2709 bool PhaseMacroExpand::expand_macro_nodes() {
2710 // Last attempt to eliminate macro nodes.
2711 eliminate_macro_nodes();
2712
2713 // Make sure expansion will not cause node limit to be exceeded.
2714 // Worst case is a macro node gets expanded into about 200 nodes.
2715 // Allow 50% more for optimization.
2716 if (C->check_node_count(C->macro_count() * 300, "out of nodes before macro expansion" ) )
2717 return true;
2718
2719 // Eliminate Opaque and LoopLimit nodes. Do it after all loop optimizations.
2720 bool progress = true;
2721 while (progress) {
2722 progress = false;
2723 for (int i = C->macro_count(); i > 0; i--) {
2724 Node * n = C->macro_node(i-1);
2725 bool success = false;
2726 debug_only(int old_macro_count = C->macro_count(););
2727 if (n->Opcode() == Op_LoopLimit) {
2728 // Remove it from macro list and put on IGVN worklist to optimize.
2729 C->remove_macro_node(n);
2730 _igvn._worklist.push(n);
2731 success = true;
2732 } else if (n->Opcode() == Op_CallStaticJava) {
2733 // Remove it from macro list and put on IGVN worklist to optimize.
2734 C->remove_macro_node(n);
2735 _igvn._worklist.push(n);
2736 success = true;
2737 } else if (n->Opcode() == Op_Opaque1 || n->Opcode() == Op_Opaque2) {
2738 _igvn.replace_node(n, n->in(1));
2739 success = true;
2740 #if INCLUDE_RTM_OPT
2741 } else if ((n->Opcode() == Op_Opaque3) && ((Opaque3Node*)n)->rtm_opt()) {
2742 assert(C->profile_rtm(), "should be used only in rtm deoptimization code");
2743 assert((n->outcnt() == 1) && n->unique_out()->is_Cmp(), "");
2744 Node* cmp = n->unique_out();
2745 #ifdef ASSERT
2746 // Validate graph.
2747 assert((cmp->outcnt() == 1) && cmp->unique_out()->is_Bool(), "");
2748 BoolNode* bol = cmp->unique_out()->as_Bool();
2749 assert((bol->outcnt() == 1) && bol->unique_out()->is_If() &&
2750 (bol->_test._test == BoolTest::ne), "");
2751 IfNode* ifn = bol->unique_out()->as_If();
2752 assert((ifn->outcnt() == 2) &&
2753 ifn->proj_out(1)->is_uncommon_trap_proj(Deoptimization::Reason_rtm_state_change) != NULL, "");
2754 #endif
2755 Node* repl = n->in(1);
2756 if (!_has_locks) {
2757 // Remove RTM state check if there are no locks in the code.
2758 // Replace input to compare the same value.
2759 repl = (cmp->in(1) == n) ? cmp->in(2) : cmp->in(1);
2760 }
2761 _igvn.replace_node(n, repl);
2762 success = true;
2763 #endif
2764 } else if (n->Opcode() == Op_Opaque4) {
2765 Node* res = ((Opaque4Node*)n)->adjust_strip_mined_loop(&_igvn);
2766 guarantee(res != NULL, "strip mined adjustment failed");
2767 _igvn.replace_node(n, res);
2768 success = true;
2769 }
2770 assert(success == (C->macro_count() < old_macro_count), "elimination reduces macro count");
2771 progress = progress || success;
2772 }
2773 }
2774
2775 // expand arraycopy "macro" nodes first
2776 // For ReduceBulkZeroing, we must first process all arraycopy nodes
2777 // before the allocate nodes are expanded.
2778 int macro_idx = C->macro_count() - 1;
2779 while (macro_idx >= 0) {
2780 Node * n = C->macro_node(macro_idx);
2781 assert(n->is_macro(), "only macro nodes expected here");
2782 if (_igvn.type(n) == Type::TOP || n->in(0)->is_top() ) {
2783 // node is unreachable, so don't try to expand it
2784 C->remove_macro_node(n);
2785 } else if (n->is_ArrayCopy()){
2786 int macro_count = C->macro_count();
2787 expand_arraycopy_node(n->as_ArrayCopy());
2788 assert(C->macro_count() < macro_count, "must have deleted a node from macro list");
2789 }
2790 if (C->failing()) return true;
2791 macro_idx --;
2792 }
2793
2794 // expand "macro" nodes
2795 // nodes are removed from the macro list as they are processed
2796 while (C->macro_count() > 0) {
2797 int macro_count = C->macro_count();
2798 Node * n = C->macro_node(macro_count-1);
2799 assert(n->is_macro(), "only macro nodes expected here");
2800 if (_igvn.type(n) == Type::TOP || n->in(0)->is_top() ) {
2801 // node is unreachable, so don't try to expand it
2802 C->remove_macro_node(n);
2803 continue;
2804 }
2805 switch (n->class_id()) {
2806 case Node::Class_Allocate:
2807 expand_allocate(n->as_Allocate());
2808 break;
2809 case Node::Class_AllocateArray:
2810 expand_allocate_array(n->as_AllocateArray());
2811 break;
2812 case Node::Class_Lock:
2813 expand_lock_node(n->as_Lock());
2814 break;
2815 case Node::Class_Unlock:
2816 expand_unlock_node(n->as_Unlock());
2817 break;
2818 default:
2819 assert(false, "unknown node type in macro list");
2820 }
2821 assert(C->macro_count() < macro_count, "must have deleted a node from macro list");
2822 if (C->failing()) return true;
2823 }
2824
2825 _igvn.set_delay_transform(false);
2826 _igvn.optimize();
2827 if (C->failing()) return true;
2828 return false;
2829 }