1 /*
2 * Copyright (c) 2017, 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 "ci/ciValueKlass.hpp"
27 #include "opto/addnode.hpp"
28 #include "opto/castnode.hpp"
29 #include "opto/graphKit.hpp"
30 #include "opto/rootnode.hpp"
31 #include "opto/valuetypenode.hpp"
32 #include "opto/phaseX.hpp"
33
34 // Clones the values type to handle control flow merges involving multiple value types.
35 // The inputs are replaced by PhiNodes to represent the merged values for the given region.
36 ValueTypeBaseNode* ValueTypeBaseNode::clone_with_phis(PhaseGVN* gvn, Node* region) {
37 assert(!has_phi_inputs(region), "already cloned with phis");
38 ValueTypeBaseNode* vt = clone()->as_ValueTypeBase();
39
40 // Create a PhiNode for merging the oop values
41 const Type* phi_type = Type::get_const_type(value_klass());
42 PhiNode* oop = PhiNode::make(region, vt->get_oop(), phi_type);
43 gvn->set_type(oop, phi_type);
44 vt->set_oop(oop);
45
46 // Create a PhiNode each for merging the field values
47 for (uint i = 0; i < vt->field_count(); ++i) {
48 ciType* type = vt->field_type(i);
49 Node* value = vt->field_value(i);
50 if (type->is_valuetype()) {
51 // Handle flattened value type fields recursively
52 value = value->as_ValueType()->clone_with_phis(gvn, region);
53 } else {
54 phi_type = Type::get_const_type(type);
55 value = PhiNode::make(region, value, phi_type);
56 gvn->set_type(value, phi_type);
57 }
58 vt->set_field_value(i, value);
59 }
60 gvn->set_type(vt, vt->bottom_type());
61 return vt;
62 }
63
64 // Checks if the inputs of the ValueBaseTypeNode were replaced by PhiNodes
65 // for the given region (see ValueBaseTypeNode::clone_with_phis).
66 bool ValueTypeBaseNode::has_phi_inputs(Node* region) {
67 // Check oop input
68 bool result = get_oop()->is_Phi() && get_oop()->as_Phi()->region() == region;
69 #ifdef ASSERT
70 if (result) {
71 // Check all field value inputs for consistency
72 for (uint i = Oop; i < field_count(); ++i) {
73 Node* n = in(i);
74 if (n->is_ValueTypeBase()) {
75 assert(n->as_ValueTypeBase()->has_phi_inputs(region), "inconsistent phi inputs");
76 } else {
77 assert(n->is_Phi() && n->as_Phi()->region() == region, "inconsistent phi inputs");
78 }
79 }
80 }
81 #endif
82 return result;
83 }
84
85 // Merges 'this' with 'other' by updating the input PhiNodes added by 'clone_with_phis'
86 ValueTypeBaseNode* ValueTypeBaseNode::merge_with(PhaseGVN* gvn, const ValueTypeBaseNode* other, int pnum, bool transform) {
87 // Merge oop inputs
88 PhiNode* phi = get_oop()->as_Phi();
89 phi->set_req(pnum, other->get_oop());
90 if (transform) {
91 set_oop(gvn->transform(phi));
92 gvn->record_for_igvn(phi);
93 }
94 // Merge field values
95 for (uint i = 0; i < field_count(); ++i) {
96 Node* val1 = field_value(i);
97 Node* val2 = other->field_value(i);
98 if (val1->isa_ValueType()) {
99 val1->as_ValueType()->merge_with(gvn, val2->as_ValueType(), pnum, transform);
100 } else {
101 assert(val1->is_Phi(), "must be a phi node");
102 assert(!val2->is_ValueType(), "inconsistent merge values");
103 val1->set_req(pnum, val2);
104 }
105 if (transform) {
106 set_field_value(i, gvn->transform(val1));
107 gvn->record_for_igvn(val1);
108 }
109 }
110 return this;
111 }
112
113 // Adds a new merge path to a valuetype node with phi inputs
114 void ValueTypeBaseNode::add_new_path(Node* region) {
115 assert(has_phi_inputs(region), "must have phi inputs");
116
117 PhiNode* phi = get_oop()->as_Phi();
118 phi->add_req(NULL);
119 assert(phi->req() == region->req(), "must be same size as region");
120
121 for (uint i = 0; i < field_count(); ++i) {
122 Node* val = field_value(i);
123 if (val->isa_ValueType()) {
124 val->as_ValueType()->add_new_path(region);
125 } else {
126 val->as_Phi()->add_req(NULL);
127 assert(val->req() == region->req(), "must be same size as region");
128 }
129 }
130 }
131
132 Node* ValueTypeBaseNode::field_value(uint index) const {
133 assert(index < field_count(), "index out of bounds");
134 return in(Values + index);
135 }
136
137 // Get the value of the field at the given offset.
138 // If 'recursive' is true, flattened value type fields will be resolved recursively.
139 Node* ValueTypeBaseNode::field_value_by_offset(int offset, bool recursive) const {
140 // If the field at 'offset' belongs to a flattened value type field, 'index' refers to the
141 // corresponding ValueTypeNode input and 'sub_offset' is the offset in flattened value type.
142 int index = value_klass()->field_index_by_offset(offset);
143 int sub_offset = offset - field_offset(index);
144 Node* value = field_value(index);
145 assert(value != NULL, "field value not found");
146 if (recursive && value->is_ValueType()) {
147 ValueTypeNode* vt = value->as_ValueType();
148 if (field_is_flattened(index)) {
149 // Flattened value type field
150 sub_offset += vt->value_klass()->first_field_offset(); // Add header size
151 return vt->field_value_by_offset(sub_offset, recursive);
152 } else {
153 assert(sub_offset == 0, "should not have a sub offset");
154 return vt;
155 }
156 }
157 assert(!(recursive && value->is_ValueType()), "should not be a value type");
158 assert(sub_offset == 0, "offset mismatch");
159 return value;
160 }
161
162 void ValueTypeBaseNode::set_field_value(uint index, Node* value) {
163 assert(index < field_count(), "index out of bounds");
164 set_req(Values + index, value);
165 }
166
167 int ValueTypeBaseNode::field_offset(uint index) const {
168 assert(index < field_count(), "index out of bounds");
169 return value_klass()->declared_nonstatic_field_at(index)->offset();
170 }
171
172 ciType* ValueTypeBaseNode::field_type(uint index) const {
173 assert(index < field_count(), "index out of bounds");
174 return value_klass()->declared_nonstatic_field_at(index)->type();
175 }
176
177 bool ValueTypeBaseNode::field_is_flattened(uint index) const {
178 assert(index < field_count(), "index out of bounds");
179 ciField* field = value_klass()->declared_nonstatic_field_at(index);
180 assert(!field->is_flattened() || field->type()->is_valuetype(), "must be a value type");
181 return field->is_flattened();
182 }
183
184 bool ValueTypeBaseNode::field_is_flattenable(uint index) const {
185 assert(index < field_count(), "index out of bounds");
186 ciField* field = value_klass()->declared_nonstatic_field_at(index);
187 assert(!field->is_flattenable() || field->type()->is_valuetype(), "must be a value type");
188 return field->is_flattenable();
189 }
190
191 int ValueTypeBaseNode::make_scalar_in_safepoint(Unique_Node_List& worklist, SafePointNode* sfpt, Node* root, PhaseGVN* gvn) {
192 ciValueKlass* vk = value_klass();
193 uint nfields = vk->nof_nonstatic_fields();
194 JVMState* jvms = sfpt->jvms();
195 int start = jvms->debug_start();
196 int end = jvms->debug_end();
197 // Replace safepoint edge by SafePointScalarObjectNode and add field values
198 assert(jvms != NULL, "missing JVMS");
199 uint first_ind = (sfpt->req() - jvms->scloff());
200 SafePointScalarObjectNode* sobj = new SafePointScalarObjectNode(value_ptr(),
201 #ifdef ASSERT
202 NULL,
203 #endif
204 first_ind, nfields);
205 sobj->init_req(0, root);
206 // Iterate over the value type fields in order of increasing
207 // offset and add the field values to the safepoint.
208 for (uint j = 0; j < nfields; ++j) {
209 int offset = vk->nonstatic_field_at(j)->offset();
210 Node* value = field_value_by_offset(offset, true /* include flattened value type fields */);
211 if (value->is_ValueType()) {
212 if (value->as_ValueType()->is_allocated(gvn)) {
213 value = value->as_ValueType()->get_oop();
214 } else {
215 // Add non-flattened value type field to the worklist to process later
216 worklist.push(value);
217 }
218 }
219 sfpt->add_req(value);
220 }
221 jvms->set_endoff(sfpt->req());
222 if (gvn != NULL) {
223 sobj = gvn->transform(sobj)->as_SafePointScalarObject();
224 gvn->igvn_rehash_node_delayed(sfpt);
225 }
226 return sfpt->replace_edges_in_range(this, sobj, start, end);
227 }
228
229 void ValueTypeBaseNode::make_scalar_in_safepoints(Node* root, PhaseGVN* gvn) {
230 // Process all safepoint uses and scalarize value type
231 Unique_Node_List worklist;
232 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
233 Node* u = fast_out(i);
234 if (u->is_SafePoint() && !u->is_CallLeaf() && (!u->is_Call() || u->as_Call()->has_debug_use(this))) {
235 SafePointNode* sfpt = u->as_SafePoint();
236 Node* in_oop = get_oop();
237 const Type* oop_type = in_oop->bottom_type();
238 assert(Opcode() == Op_ValueTypePtr || !isa_ValueType()->is_allocated(gvn), "already heap allocated value types should be linked directly");
239 int nb = make_scalar_in_safepoint(worklist, sfpt, root, gvn);
240 --i; imax -= nb;
241 }
242 }
243 // Now scalarize non-flattened fields
244 for (uint i = 0; i < worklist.size(); ++i) {
245 Node* vt = worklist.at(i);
246 vt->as_ValueType()->make_scalar_in_safepoints(root, gvn);
247 }
248 }
249
250 void ValueTypeBaseNode::initialize(GraphKit* kit, MultiNode* multi, ciValueKlass* vk, int base_offset, int base_input, bool in) {
251 assert(base_offset >= 0, "offset in value type must be positive");
252 PhaseGVN& gvn = kit->gvn();
253 for (uint i = 0; i < field_count(); i++) {
254 ciType* ft = field_type(i);
255 int offset = base_offset + field_offset(i);
256 if (field_is_flattened(i)) {
257 // Flattened value type field
258 ValueTypeNode* vt = ValueTypeNode::make_uninitialized(gvn, ft->as_value_klass());
259 vt->initialize(kit, multi, vk, offset - value_klass()->first_field_offset(), base_input, in);
260 set_field_value(i, gvn.transform(vt));
261 } else {
262 int j = 0; int extra = 0;
263 for (; j < vk->nof_nonstatic_fields(); j++) {
264 ciField* f = vk->nonstatic_field_at(j);
265 if (offset == f->offset()) {
266 assert(f->type() == ft, "inconsistent field type");
267 break;
268 }
269 BasicType bt = f->type()->basic_type();
270 if (bt == T_LONG || bt == T_DOUBLE) {
271 extra++;
272 }
273 }
274 assert(j != vk->nof_nonstatic_fields(), "must find");
275 Node* parm = NULL;
276 if (multi->is_Start()) {
277 assert(in, "return from start?");
278 parm = gvn.transform(new ParmNode(multi->as_Start(), base_input + j + extra));
279 } else {
280 if (in) {
281 parm = multi->as_Call()->in(base_input + j + extra);
282 } else {
283 parm = gvn.transform(new ProjNode(multi->as_Call(), base_input + j + extra));
284 }
285 }
286 if (ft->is_valuetype()) {
287 // Non-flattened value type field
288 assert(!gvn.type(parm)->is_ptr()->maybe_null(), "should never be null");
289 parm = ValueTypeNode::make_from_oop(kit, parm, ft->as_value_klass());
290 }
291 set_field_value(i, parm);
292 // Record all these guys for later GVN.
293 gvn.record_for_igvn(parm);
294 }
295 }
296 }
297
298 const TypePtr* ValueTypeBaseNode::field_adr_type(Node* base, int offset, ciInstanceKlass* holder, PhaseGVN& gvn) const {
299 const TypeAryPtr* ary_type = gvn.type(base)->isa_aryptr();
300 const TypePtr* adr_type = NULL;
301 bool is_array = ary_type != NULL;
302 if (is_array) {
303 // In the case of a flattened value type array, each field has its own slice
304 adr_type = ary_type->with_field_offset(offset)->add_offset(Type::OffsetBot);
305 } else {
306 ciField* field = holder->get_field_by_offset(offset, false);
307 assert(field != NULL, "field not found");
308 adr_type = gvn.C->alias_type(field)->adr_type();
309 }
310 return adr_type;
311 }
312
313 void ValueTypeBaseNode::load(GraphKit* kit, Node* base, Node* ptr, ciInstanceKlass* holder, int holder_offset, int trap_bci) {
314 // Initialize the value type by loading its field values from
315 // memory and adding the values as input edges to the node.
316 for (uint i = 0; i < field_count(); ++i) {
317 int offset = holder_offset + field_offset(i);
318 Node* value = NULL;
319 ciType* ft = field_type(i);
320 if (field_is_flattened(i)) {
321 // Recursively load the flattened value type field
322 value = ValueTypeNode::make_from_flattened(kit, ft->as_value_klass(), base, ptr, holder, offset);
323 } else {
324 const TypeOopPtr* oop_ptr = kit->gvn().type(base)->isa_oopptr();
325 bool is_array = (oop_ptr->isa_aryptr() != NULL);
326 if (base->is_Con() && !is_array) {
327 // If the oop to the value type is constant (static final field), we can
328 // also treat the fields as constants because the value type is immutable.
329 ciObject* constant_oop = oop_ptr->const_oop();
330 ciField* field = holder->get_field_by_offset(offset, false);
331 assert(field != NULL, "field not found");
332 ciConstant constant = constant_oop->as_instance()->field_value(field);
333 const Type* con_type = Type::make_from_constant(constant, /*require_const=*/ true);
334 assert(con_type != NULL, "type not found");
335 value = kit->gvn().transform(kit->makecon(con_type));
336 } else {
337 // Load field value from memory
338 const TypePtr* adr_type = field_adr_type(base, offset, holder, kit->gvn());
339 Node* adr = kit->basic_plus_adr(base, ptr, offset);
340 BasicType bt = type2field[ft->basic_type()];
341 assert(is_java_primitive(bt) || adr->bottom_type()->is_ptr_to_narrowoop() == UseCompressedOops, "inconsistent");
342 const Type* val_type = Type::get_const_type(ft);
343 DecoratorSet decorators = IN_HEAP | MO_UNORDERED;
344 if (is_array) {
345 decorators |= IS_ARRAY;
346 }
347 value = kit->access_load_at(base, adr, adr_type, val_type, bt, decorators);
348 }
349 if (ft->is_valuetype()) {
350 // Loading a non-flattened value type from memory
351 value = ValueTypeNode::make_from_oop(kit, value, ft->as_value_klass(), /* buffer_check */ false, /* null2default */ field_is_flattenable(i), trap_bci);
352 }
353 }
354 set_field_value(i, value);
355 }
356 }
357
358 void ValueTypeBaseNode::store_flattened(GraphKit* kit, Node* base, Node* ptr, ciInstanceKlass* holder, int holder_offset) const {
359 // The value type is embedded into the object without an oop header. Subtract the
360 // offset of the first field to account for the missing header when storing the values.
361 if (holder == NULL) {
362 holder = value_klass();
363 }
364 holder_offset -= value_klass()->first_field_offset();
365 store(kit, base, ptr, holder, holder_offset);
366 }
367
368 void ValueTypeBaseNode::store(GraphKit* kit, Node* base, Node* ptr, ciInstanceKlass* holder, int holder_offset, bool deoptimize_on_exception) const {
369 // Write field values to memory
370 for (uint i = 0; i < field_count(); ++i) {
371 int offset = holder_offset + field_offset(i);
372 Node* value = field_value(i);
373 ciType* ft = field_type(i);
374 if (field_is_flattened(i)) {
375 // Recursively store the flattened value type field
376 value->as_ValueType()->store_flattened(kit, base, ptr, holder, offset);
377 } else {
378 // Store field value to memory
379 const TypePtr* adr_type = field_adr_type(base, offset, holder, kit->gvn());
380 Node* adr = kit->basic_plus_adr(base, ptr, offset);
381 BasicType bt = type2field[ft->basic_type()];
382 assert(is_java_primitive(bt) || adr->bottom_type()->is_ptr_to_narrowoop() == UseCompressedOops, "inconsistent");
383 const Type* val_type = Type::get_const_type(ft);
384 const TypeAryPtr* ary_type = kit->gvn().type(base)->isa_aryptr();
385 DecoratorSet decorators = IN_HEAP | MO_UNORDERED;
386 if (ary_type != NULL) {
387 decorators |= IS_ARRAY;
388 }
389 kit->access_store_at(kit->control(), base, adr, adr_type, value, val_type, bt, decorators, deoptimize_on_exception);
390 }
391 }
392 }
393
394 ValueTypeBaseNode* ValueTypeBaseNode::allocate(GraphKit* kit, bool deoptimize_on_exception) {
395 // Check if value type is already allocated
396 Node* null_ctl = kit->top();
397 Node* not_null_oop = kit->null_check_oop(get_oop(), &null_ctl);
398 if (null_ctl->is_top()) {
399 // Value type is allocated
400 return this;
401 }
402 assert(!is_allocated(&kit->gvn()), "should not be allocated");
403 RegionNode* region = new RegionNode(3);
404
405 // Oop is non-NULL, use it
406 region->init_req(1, kit->control());
407 PhiNode* oop = PhiNode::make(region, not_null_oop, value_ptr());
408 PhiNode* io = PhiNode::make(region, kit->i_o(), Type::ABIO);
409 PhiNode* mem = PhiNode::make(region, kit->merged_memory(), Type::MEMORY, TypePtr::BOTTOM);
410
411 {
412 // Oop is NULL, allocate and initialize buffer
413 PreserveJVMState pjvms(kit);
414 kit->set_control(null_ctl);
415 kit->kill_dead_locals();
416 ciValueKlass* vk = value_klass();
417 Node* klass_node = kit->makecon(TypeKlassPtr::make(vk));
418 Node* alloc_oop = kit->new_instance(klass_node, NULL, NULL, deoptimize_on_exception, this);
419 store(kit, alloc_oop, alloc_oop, vk, 0, deoptimize_on_exception);
420 region->init_req(2, kit->control());
421 oop ->init_req(2, alloc_oop);
422 io ->init_req(2, kit->i_o());
423 mem ->init_req(2, kit->merged_memory());
424 }
425
426 // Update GraphKit
427 kit->set_control(kit->gvn().transform(region));
428 kit->set_i_o(kit->gvn().transform(io));
429 kit->set_all_memory(kit->gvn().transform(mem));
430 kit->record_for_igvn(region);
431 kit->record_for_igvn(oop);
432 kit->record_for_igvn(io);
433 kit->record_for_igvn(mem);
434
435 // Use cloned ValueTypeNode to propagate oop from now on
436 Node* res_oop = kit->gvn().transform(oop);
437 ValueTypeBaseNode* vt = clone()->as_ValueTypeBase();
438 vt->set_oop(res_oop);
439 vt = kit->gvn().transform(vt)->as_ValueTypeBase();
440 kit->replace_in_map(this, vt);
441 return vt;
442 }
443
444 bool ValueTypeBaseNode::is_allocated(PhaseGVN* phase) const {
445 Node* oop = get_oop();
446 const Type* oop_type = (phase != NULL) ? phase->type(oop) : oop->bottom_type();
447 return !oop_type->is_ptr()->maybe_null();
448 }
449
450 // When a call returns multiple values, it has several result
451 // projections, one per field. Replacing the result of the call by a
452 // value type node (after late inlining) requires that for each result
453 // projection, we find the corresponding value type field.
454 void ValueTypeBaseNode::replace_call_results(GraphKit* kit, Node* call, Compile* C) {
455 ciValueKlass* vk = value_klass();
456 for (DUIterator_Fast imax, i = call->fast_outs(imax); i < imax; i++) {
457 ProjNode* pn = call->fast_out(i)->as_Proj();
458 uint con = pn->_con;
459 if (con >= TypeFunc::Parms+1) {
460 uint field_nb = con - (TypeFunc::Parms+1);
461 int extra = 0;
462 for (uint j = 0; j < field_nb - extra; j++) {
463 ciField* f = vk->nonstatic_field_at(j);
464 BasicType bt = f->type()->basic_type();
465 if (bt == T_LONG || bt == T_DOUBLE) {
466 extra++;
467 }
468 }
469 ciField* f = vk->nonstatic_field_at(field_nb - extra);
470 Node* field = field_value_by_offset(f->offset(), true);
471 if (field->is_ValueType()) {
472 assert(f->is_flattened(), "should be flattened");
473 field = field->as_ValueType()->allocate(kit)->get_oop();
474 }
475 C->gvn_replace_by(pn, field);
476 C->initial_gvn()->hash_delete(pn);
477 pn->set_req(0, C->top());
478 --i; --imax;
479 }
480 }
481 }
482
483 ValueTypeNode* ValueTypeNode::make_uninitialized(PhaseGVN& gvn, ciValueKlass* klass) {
484 // Create a new ValueTypeNode with uninitialized values and NULL oop
485 const TypeValueType* type = TypeValueType::make(klass);
486 return new ValueTypeNode(type, gvn.zerocon(T_VALUETYPE));
487 }
488
489 Node* ValueTypeNode::default_oop(PhaseGVN& gvn, ciValueKlass* vk) {
490 // Returns the constant oop of the default value type allocation
491 return gvn.makecon(TypeInstPtr::make(vk->default_value_instance()));
492 }
493
494 ValueTypeNode* ValueTypeNode::make_default(PhaseGVN& gvn, ciValueKlass* vk) {
495 // Create a new ValueTypeNode with default values
496 Node* oop = default_oop(gvn, vk);
497 const TypeValueType* type = TypeValueType::make(vk);
498 ValueTypeNode* vt = new ValueTypeNode(type, oop);
499 for (uint i = 0; i < vt->field_count(); ++i) {
500 ciType* field_type = vt->field_type(i);
501 Node* value = NULL;
502 if (field_type->is_valuetype()) {
503 value = ValueTypeNode::make_default(gvn, field_type->as_value_klass());
504 } else {
505 value = gvn.zerocon(field_type->basic_type());
506 }
507 vt->set_field_value(i, value);
508 }
509 vt = gvn.transform(vt)->as_ValueType();
510 assert(vt->is_default(gvn), "must be the default value type");
511 return vt;
512 }
513
514
515 bool ValueTypeNode::is_default(PhaseGVN& gvn) const {
516 for (uint i = 0; i < field_count(); ++i) {
517 Node* value = field_value(i);
518 if (!gvn.type(value)->is_zero_type() &&
519 !(value->is_ValueType() && value->as_ValueType()->is_default(gvn))) {
520 return false;
521 }
522 }
523 return true;
524 }
525
526 ValueTypeNode* ValueTypeNode::make_from_oop(GraphKit* kit, Node* oop, ciValueKlass* vk, bool buffer_check, bool null2default, int trap_bci) {
527 PhaseGVN& gvn = kit->gvn();
528 const TypePtr* oop_type = gvn.type(oop)->is_ptr();
529 bool null_check = oop_type->maybe_null();
530
531 // Create and initialize a ValueTypeNode by loading all field
532 // values from a heap-allocated version and also save the oop.
533 ValueTypeNode* vt = new ValueTypeNode(TypeValueType::make(vk), oop);
534
535 if (null_check) {
536 // Add a null check because the oop may be null
537 Node* null_ctl = kit->top();
538 Node* not_null_oop = kit->null_check_oop(oop, &null_ctl);
539 if (kit->stopped()) {
540 // Constant null
541 if (null2default) {
542 kit->set_control(null_ctl);
543 return make_default(gvn, vk);
544 } else {
545 int bci = kit->bci();
546 if (trap_bci != -1) {
547 // Put trap at different bytecode
548 kit->push(kit->null());
549 kit->set_bci(trap_bci);
550 }
551 kit->replace_in_map(oop, kit->null());
552 kit->uncommon_trap(Deoptimization::Reason_null_check, Deoptimization::Action_none);
553 kit->set_bci(bci);
554 return NULL;
555 }
556 }
557 vt->set_oop(not_null_oop);
558 vt->load(kit, not_null_oop, not_null_oop, vk, /* holder_offset */ 0, trap_bci);
559
560 if (null2default && (null_ctl != kit->top())) {
561 // Return default value type if oop is null
562 ValueTypeNode* def = make_default(gvn, vk);
563 Node* region = new RegionNode(3);
564 region->init_req(1, kit->control());
565 region->init_req(2, null_ctl);
566
567 vt = vt->clone_with_phis(&gvn, region)->as_ValueType();
568 vt->merge_with(&gvn, def, 2, true);
569 kit->set_control(gvn.transform(region));
570 } else if (null_ctl != kit->top()) {
571 // Deoptimize if oop is null
572 PreserveJVMState pjvms(kit);
573 kit->set_control(null_ctl);
574 int bci = kit->bci();
575 if (trap_bci != -1) {
576 // Put trap at different bytecode
577 kit->push(kit->null());
578 kit->set_bci(trap_bci);
579 }
580 kit->replace_in_map(oop, kit->null());
581 kit->uncommon_trap(Deoptimization::Reason_null_check, Deoptimization::Action_none);
582 kit->set_bci(bci);
583 }
584 } else {
585 // Oop can never be null
586 Node* init_ctl = kit->control();
587 vt->load(kit, oop, oop, vk, /* holder_offset */ 0, trap_bci);
588 assert(init_ctl != kit->control() || oop->is_Con() || oop->is_CheckCastPP() || oop->Opcode() == Op_ValueTypePtr ||
589 vt->is_loaded(&gvn) == oop, "value type should be loaded");
590 }
591
592 if (buffer_check && vk->is_bufferable()) {
593 // Check if oop is in heap bounds or if it points into the vtBuffer:
594 // base <= oop < (base + size) <=> (oop - base) <U size
595 // Discard buffer oops to avoid storing them into fields or arrays.
596 assert(!gvn.type(oop)->isa_narrowoop(), "should not be a narrow oop");
597 Node* heap_base = gvn.MakeConX((intptr_t)Universe::heap()->base());
598 Node* heap_size = gvn.MakeConX(Universe::heap()->max_capacity());
599 Node* sub = gvn.transform(new SubXNode(gvn.transform(new CastP2XNode(NULL, oop)), heap_base));
600 Node* chk = gvn.transform(new CmpUXNode(sub, heap_size));
601 Node* tst = gvn.transform(new BoolNode(chk, BoolTest::lt));
602 IfNode* iff = gvn.transform(new IfNode(kit->control(), tst, PROB_MAX, COUNT_UNKNOWN))->as_If();
603
604 Node* region = new RegionNode(3);
605 region->init_req(1, gvn.transform(new IfTrueNode(iff)));
606 region->init_req(2, gvn.transform(new IfFalseNode(iff)));
607 Node* new_oop = new PhiNode(region, vt->value_ptr());
608 new_oop->init_req(1, oop);
609 new_oop->init_req(2, gvn.zerocon(T_VALUETYPE));
610
611 gvn.hash_delete(vt);
612 vt->set_oop(gvn.transform(new_oop));
613 kit->set_control(gvn.transform(region));
614 }
615
616 assert(vt->is_allocated(&gvn), "value type should be allocated");
617 return gvn.transform(vt)->as_ValueType();
618 }
619
620 // GraphKit wrapper for the 'make_from_flattened' method
621 ValueTypeNode* ValueTypeNode::make_from_flattened(GraphKit* kit, ciValueKlass* vk, Node* obj, Node* ptr, ciInstanceKlass* holder, int holder_offset) {
622 // Create and initialize a ValueTypeNode by loading all field values from
623 // a flattened value type field at 'holder_offset' or from a value type array.
624 ValueTypeNode* vt = make_uninitialized(kit->gvn(), vk);
625 // The value type is flattened into the object without an oop header. Subtract the
626 // offset of the first field to account for the missing header when loading the values.
627 holder_offset -= vk->first_field_offset();
628 vt->load(kit, obj, ptr, holder, holder_offset);
629 assert(vt->is_loaded(&kit->gvn()) != obj, "holder oop should not be used as flattened value type oop");
630 return kit->gvn().transform(vt)->as_ValueType();
631 }
632
633 ValueTypeNode* ValueTypeNode::make_from_multi(GraphKit* kit, MultiNode* multi, ciValueKlass* vk, int base_input, bool in) {
634 ValueTypeNode* vt = ValueTypeNode::make_uninitialized(kit->gvn(), vk);
635 vt->initialize(kit, multi, vk, 0, base_input, in);
636 return kit->gvn().transform(vt)->as_ValueType();
637 }
638
639 Node* ValueTypeNode::is_loaded(PhaseGVN* phase, ciValueKlass* vk, Node* base, int holder_offset) {
640 if (vk == NULL) {
641 vk = value_klass();
642 }
643 if (field_count() == 0) {
644 assert(is_allocated(phase), "must be allocated");
645 return get_oop();
646 }
647 for (uint i = 0; i < field_count(); ++i) {
648 int offset = holder_offset + field_offset(i);
649 Node* value = field_value(i);
650 if (value->isa_ValueType()) {
651 ValueTypeNode* vt = value->as_ValueType();
652 if (field_is_flattened(i)) {
653 // Check value type field load recursively
654 base = vt->is_loaded(phase, vk, base, offset - vt->value_klass()->first_field_offset());
655 if (base == NULL) {
656 return NULL;
657 }
658 continue;
659 } else {
660 value = vt->get_oop();
661 if (value->Opcode() == Op_CastPP) {
662 // Skip CastPP
663 value = value->in(1);
664 }
665 }
666 }
667 if (value->isa_DecodeN()) {
668 // Skip DecodeN
669 value = value->in(1);
670 }
671 if (value->isa_Load()) {
672 // Check if base and offset of field load matches value type layout
673 intptr_t loffset = 0;
674 Node* lbase = AddPNode::Ideal_base_and_offset(value->in(MemNode::Address), phase, loffset);
675 if (lbase == NULL || (lbase != base && base != NULL) || loffset != offset) {
676 return NULL;
677 } else if (base == NULL) {
678 // Set base and check if pointer type matches
679 base = lbase;
680 const TypeInstPtr* vtptr = phase->type(base)->isa_instptr();
681 if (vtptr == NULL || !vtptr->klass()->equals(vk)) {
682 return NULL;
683 }
684 }
685 } else {
686 return NULL;
687 }
688 }
689 return base;
690 }
691
692 Node* ValueTypeNode::allocate_fields(GraphKit* kit) {
693 ValueTypeNode* vt = clone()->as_ValueType();
694 for (uint i = 0; i < field_count(); i++) {
695 ValueTypeNode* value = field_value(i)->isa_ValueType();
696 if (field_is_flattened(i)) {
697 // Flattened value type field
698 vt->set_field_value(i, value->allocate_fields(kit));
699 } else if (value != NULL){
700 // Non-flattened value type field
701 vt->set_field_value(i, value->allocate(kit));
702 }
703 }
704 vt = kit->gvn().transform(vt)->as_ValueType();
705 kit->replace_in_map(this, vt);
706 return vt;
707 }
708
709 Node* ValueTypeNode::tagged_klass(PhaseGVN& gvn) {
710 ciValueKlass* vk = value_klass();
711 const TypeKlassPtr* tk = TypeKlassPtr::make(vk);
712 intptr_t bits = tk->get_con();
713 set_nth_bit(bits, 0);
714 return gvn.makecon(TypeRawPtr::make((address)bits));
715 }
716
717 void ValueTypeNode::pass_klass(Node* n, uint pos, const GraphKit& kit) {
718 n->init_req(pos, tagged_klass(kit.gvn()));
719 }
720
721 uint ValueTypeNode::pass_fields(Node* n, int base_input, GraphKit& kit, bool assert_allocated, ciValueKlass* base_vk, int base_offset) {
722 ciValueKlass* vk = value_klass();
723 if (base_vk == NULL) {
724 base_vk = vk;
725 }
726 uint edges = 0;
727 for (uint i = 0; i < field_count(); i++) {
728 int offset = base_offset + field_offset(i) - (base_offset > 0 ? vk->first_field_offset() : 0);
729 Node* arg = field_value(i);
730 if (field_is_flattened(i)) {
731 // Flattened value type field
732 edges += arg->as_ValueType()->pass_fields(n, base_input, kit, assert_allocated, base_vk, offset);
733 } else {
734 int j = 0; int extra = 0;
735 for (; j < base_vk->nof_nonstatic_fields(); j++) {
736 ciField* field = base_vk->nonstatic_field_at(j);
737 if (offset == field->offset()) {
738 assert(field->type() == field_type(i), "inconsistent field type");
739 break;
740 }
741 BasicType bt = field->type()->basic_type();
742 if (bt == T_LONG || bt == T_DOUBLE) {
743 extra++;
744 }
745 }
746 if (arg->is_ValueType()) {
747 // non-flattened value type field
748 ValueTypeNode* vt = arg->as_ValueType();
749 assert(!assert_allocated || vt->is_allocated(&kit.gvn()), "value type field should be allocated");
750 arg = vt->allocate(&kit)->get_oop();
751 }
752 n->init_req(base_input + j + extra, arg);
753 edges++;
754 BasicType bt = field_type(i)->basic_type();
755 if (bt == T_LONG || bt == T_DOUBLE) {
756 n->init_req(base_input + j + extra + 1, kit.top());
757 edges++;
758 }
759 }
760 }
761 return edges;
762 }
763
764 Node* ValueTypeNode::Ideal(PhaseGVN* phase, bool can_reshape) {
765 Node* oop = get_oop();
766 if (is_default(*phase) && (!oop->is_Con() || phase->type(oop)->is_zero_type())) {
767 // Use the pre-allocated oop for default value types
768 set_oop(default_oop(*phase, value_klass()));
769 return this;
770 }
771
772 if (!is_allocated(phase) && !value_klass()->is_bufferable()) {
773 // Save base oop if fields are loaded from memory and the value
774 // type is not buffered (in this case we should not use the oop).
775 Node* base = is_loaded(phase);
776 if (base != NULL) {
777 set_oop(base);
778 assert(is_allocated(phase), "should now be allocated");
779 return this;
780 }
781 }
782
783 if (can_reshape) {
784 PhaseIterGVN* igvn = phase->is_IterGVN();
785
786 if (is_default(*phase)) {
787 // Search for users of the default value type
788 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
789 Node* user = fast_out(i);
790 AllocateNode* alloc = user->isa_Allocate();
791 if (alloc != NULL && alloc->result_cast() != NULL && alloc->in(AllocateNode::ValueNode) == this) {
792 // Found an allocation of the default value type.
793 // If the code in StoreNode::Identity() that removes useless stores was not yet
794 // executed or ReduceFieldZeroing is disabled, there can still be initializing
795 // stores (only zero-type or default value stores, because value types are immutable).
796 Node* res = alloc->result_cast();
797 for (DUIterator_Fast jmax, j = res->fast_outs(jmax); j < jmax; j++) {
798 AddPNode* addp = res->fast_out(j)->isa_AddP();
799 if (addp != NULL) {
800 for (DUIterator_Fast kmax, k = addp->fast_outs(kmax); k < kmax; k++) {
801 StoreNode* store = addp->fast_out(k)->isa_Store();
802 if (store != NULL && store->outcnt() != 0) {
803 // Remove the useless store
804 Node* mem = store->in(MemNode::Memory);
805 Node* val = store->in(MemNode::ValueIn);
806 const Type* val_type = igvn->type(val);
807 assert(val_type->is_zero_type() || (val->is_Con() && val_type->make_ptr()->is_valuetypeptr()),
808 "must be zero-type or default value store");
809 igvn->replace_in_uses(store, mem);
810 }
811 }
812 }
813 }
814 // Replace allocation by pre-allocated oop
815 igvn->replace_node(res, default_oop(*phase, value_klass()));
816 } else if (user->is_ValueType()) {
817 // Add value type user to worklist to give it a chance to get optimized as well
818 igvn->_worklist.push(user);
819 }
820 }
821 }
822
823 if (is_allocated(igvn)) {
824 // Value type is heap allocated, search for safepoint uses
825 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
826 Node* out = fast_out(i);
827 if (out->is_SafePoint()) {
828 // Let SafePointNode::Ideal() take care of re-wiring the
829 // safepoint to the oop input instead of the value type node.
830 igvn->rehash_node_delayed(out);
831 }
832 }
833 }
834 }
835 return NULL;
836 }
837
838 // Search for multiple allocations of this value type
839 // and try to replace them by dominating allocations.
840 void ValueTypeNode::remove_redundant_allocations(PhaseIterGVN* igvn, PhaseIdealLoop* phase) {
841 assert(EliminateAllocations, "allocation elimination should be enabled");
842 // Search for allocations of this value type
843 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
844 AllocateNode* alloc = fast_out(i)->isa_Allocate();
845 if (alloc != NULL && alloc->result_cast() != NULL && alloc->in(AllocateNode::ValueNode) == this) {
846 assert(!is_default(*igvn), "default value type allocation");
847 Node* res_dom = NULL;
848 if (is_allocated(igvn)) {
849 // The value type is already allocated but still connected to an AllocateNode.
850 // This can happen with late inlining when we first allocate a value type argument
851 // but later decide to inline the call with the callee code also allocating.
852 res_dom = get_oop();
853 } else {
854 // Search for a dominating allocation of the same value type
855 for (DUIterator_Fast jmax, j = fast_outs(jmax); j < jmax; j++) {
856 Node* out2 = fast_out(j);
857 if (alloc != out2 && out2->is_Allocate() && out2->in(AllocateNode::ValueNode) == this &&
858 phase->is_dominator(out2, alloc)) {
859 AllocateNode* alloc_dom = out2->as_Allocate();
860 assert(alloc->in(AllocateNode::KlassNode) == alloc_dom->in(AllocateNode::KlassNode), "klasses should match");
861 res_dom = alloc_dom->result_cast();
862 break;
863 }
864 }
865 }
866 if (res_dom != NULL) {
867 // Move users to dominating allocation
868 Node* res = alloc->result_cast();
869 igvn->replace_node(res, res_dom);
870 // The result of the dominated allocation is now unused and will be
871 // removed later in AllocateNode::Ideal() to not confuse loop opts.
872 igvn->record_for_igvn(alloc);
873 #ifdef ASSERT
874 if (PrintEliminateAllocations) {
875 tty->print("++++ Eliminated: %d Allocate ", alloc->_idx);
876 dump_spec(tty);
877 tty->cr();
878 }
879 #endif
880 }
881 }
882 }
883
884 // Process users
885 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
886 Node* out = fast_out(i);
887 if (out->isa_ValueType() != NULL) {
888 // Recursively process value type users
889 out->as_ValueType()->remove_redundant_allocations(igvn, phase);
890 } else if (out->isa_Allocate() != NULL) {
891 // Allocate users should be linked
892 assert(out->in(AllocateNode::ValueNode) == this, "should be linked");
893 } else {
894 #ifdef ASSERT
895 // The value type should not have any other users at this time
896 out->dump();
897 assert(false, "unexpected user of value type");
898 #endif
899 }
900 }
901 }
902
903 ValueTypePtrNode* ValueTypePtrNode::make_from_value_type(GraphKit* kit, ValueTypeNode* vt, bool deoptimize_on_exception) {
904 Node* oop = vt->allocate(kit, deoptimize_on_exception)->get_oop();
905 ValueTypePtrNode* vtptr = new ValueTypePtrNode(vt->value_klass(), oop);
906 for (uint i = Oop+1; i < vt->req(); i++) {
907 vtptr->init_req(i, vt->in(i));
908 }
909 return kit->gvn().transform(vtptr)->as_ValueTypePtr();
910 }
911
912 ValueTypePtrNode* ValueTypePtrNode::make_from_call(GraphKit* kit, ciValueKlass* vk, CallNode* call) {
913 ValueTypePtrNode* vtptr = new ValueTypePtrNode(vk, kit->zerocon(T_VALUETYPE));
914 vtptr->initialize(kit, call, vk);
915 return vtptr;
916 }
917
918 ValueTypePtrNode* ValueTypePtrNode::make_from_oop(GraphKit* kit, Node* oop) {
919 // Create and initialize a ValueTypePtrNode by loading all field
920 // values from a heap-allocated version and also save the oop.
921 ciValueKlass* vk = kit->gvn().type(oop)->value_klass();
922 ValueTypePtrNode* vtptr = new ValueTypePtrNode(vk, oop);
923 vtptr->load(kit, oop, oop, vk);
924 return kit->gvn().transform(vtptr)->as_ValueTypePtr();
925 }