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() && value->isa_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->is_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->is_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 void ValueTypeBaseNode::set_field_value_by_offset(int offset, Node* value) {
168 set_field_value(field_index(offset), value);
169 }
170
171 int ValueTypeBaseNode::field_offset(uint index) const {
172 assert(index < field_count(), "index out of bounds");
173 return value_klass()->declared_nonstatic_field_at(index)->offset();
174 }
175
176 uint ValueTypeBaseNode::field_index(int offset) const {
177 uint i = 0;
178 for (; i < field_count() && field_offset(i) != offset; i++) { }
179 assert(i < field_count(), "field not found");
180 return i;
181 }
182
183 ciType* ValueTypeBaseNode::field_type(uint index) const {
184 assert(index < field_count(), "index out of bounds");
185 return value_klass()->declared_nonstatic_field_at(index)->type();
186 }
187
188 bool ValueTypeBaseNode::field_is_flattened(uint index) const {
189 assert(index < field_count(), "index out of bounds");
190 ciField* field = value_klass()->declared_nonstatic_field_at(index);
191 assert(!field->is_flattened() || field->type()->is_valuetype(), "must be a value type");
192 return field->is_flattened();
193 }
194
195 bool ValueTypeBaseNode::field_is_flattenable(uint index) const {
196 assert(index < field_count(), "index out of bounds");
197 ciField* field = value_klass()->declared_nonstatic_field_at(index);
198 assert(!field->is_flattenable() || field->type()->is_valuetype(), "must be a value type");
199 return field->is_flattenable();
200 }
201
202 int ValueTypeBaseNode::make_scalar_in_safepoint(PhaseIterGVN* igvn, Unique_Node_List& worklist, SafePointNode* sfpt) {
203 ciValueKlass* vk = value_klass();
204 uint nfields = vk->nof_nonstatic_fields();
205 JVMState* jvms = sfpt->jvms();
206 int start = jvms->debug_start();
207 int end = jvms->debug_end();
208 // Replace safepoint edge by SafePointScalarObjectNode and add field values
209 assert(jvms != NULL, "missing JVMS");
210 uint first_ind = (sfpt->req() - jvms->scloff());
211 SafePointScalarObjectNode* sobj = new SafePointScalarObjectNode(value_ptr(),
212 #ifdef ASSERT
213 NULL,
214 #endif
215 first_ind, nfields);
216 sobj->init_req(0, igvn->C->root());
217 // Iterate over the value type fields in order of increasing
218 // offset and add the field values to the safepoint.
219 for (uint j = 0; j < nfields; ++j) {
220 int offset = vk->nonstatic_field_at(j)->offset();
221 Node* value = field_value_by_offset(offset, true /* include flattened value type fields */);
222 if (value->is_ValueType()) {
223 // Add value type field to the worklist to process later
224 worklist.push(value);
225 }
226 sfpt->add_req(value);
227 }
228 jvms->set_endoff(sfpt->req());
229 sobj = igvn->transform(sobj)->as_SafePointScalarObject();
230 igvn->rehash_node_delayed(sfpt);
231 return sfpt->replace_edges_in_range(this, sobj, start, end);
232 }
233
234 void ValueTypeBaseNode::make_scalar_in_safepoints(PhaseIterGVN* igvn) {
235 // Process all safepoint uses and scalarize value type
236 Unique_Node_List worklist;
237 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
238 SafePointNode* sfpt = fast_out(i)->isa_SafePoint();
239 if (sfpt != NULL && !sfpt->is_CallLeaf() && (!sfpt->is_Call() || sfpt->as_Call()->has_debug_use(this))) {
240 int nb = 0;
241 if (is_allocated(igvn) && get_oop()->is_Con()) {
242 // Value type is allocated with a constant oop, link it directly
243 nb = sfpt->replace_edges_in_range(this, get_oop(), sfpt->jvms()->debug_start(), sfpt->jvms()->debug_end());
244 igvn->rehash_node_delayed(sfpt);
245 } else {
246 nb = make_scalar_in_safepoint(igvn, worklist, sfpt);
247 }
248 --i; imax -= nb;
249 }
250 }
251 // Now scalarize non-flattened fields
252 for (uint i = 0; i < worklist.size(); ++i) {
253 Node* vt = worklist.at(i);
254 vt->as_ValueType()->make_scalar_in_safepoints(igvn);
255 }
256 }
257
258 const TypePtr* ValueTypeBaseNode::field_adr_type(Node* base, int offset, ciInstanceKlass* holder, DecoratorSet decorators, PhaseGVN& gvn) const {
259 const TypeAryPtr* ary_type = gvn.type(base)->isa_aryptr();
260 const TypePtr* adr_type = NULL;
261 bool is_array = ary_type != NULL;
262 if ((decorators & C2_MISMATCHED) != 0) {
263 adr_type = TypeRawPtr::BOTTOM;
264 } else if (is_array) {
265 // In the case of a flattened value type array, each field has its own slice
266 adr_type = ary_type->with_field_offset(offset)->add_offset(Type::OffsetBot);
267 } else {
268 ciField* field = holder->get_field_by_offset(offset, false);
269 assert(field != NULL, "field not found");
270 adr_type = gvn.C->alias_type(field)->adr_type();
271 }
272 return adr_type;
273 }
274
275 void ValueTypeBaseNode::load(GraphKit* kit, Node* base, Node* ptr, ciInstanceKlass* holder, int holder_offset, DecoratorSet decorators) {
276 // Initialize the value type by loading its field values from
277 // memory and adding the values as input edges to the node.
278 for (uint i = 0; i < field_count(); ++i) {
279 int offset = holder_offset + field_offset(i);
280 Node* value = NULL;
281 ciType* ft = field_type(i);
282 bool is_flattenable = field_is_flattenable(i);
283 if (field_is_flattened(i)) {
284 // Recursively load the flattened value type field
285 value = ValueTypeNode::make_from_flattened(kit, ft->as_value_klass(), base, ptr, holder, offset, decorators);
286 } else {
287 const TypeOopPtr* oop_ptr = kit->gvn().type(base)->isa_oopptr();
288 bool is_array = (oop_ptr->isa_aryptr() != NULL);
289 if (base->is_Con() && !is_array) {
290 // If the oop to the value type is constant (static final field), we can
291 // also treat the fields as constants because the value type is immutable.
292 ciObject* constant_oop = oop_ptr->const_oop();
293 ciField* field = holder->get_field_by_offset(offset, false);
294 assert(field != NULL, "field not found");
295 ciConstant constant = constant_oop->as_instance()->field_value(field);
296 const Type* con_type = Type::make_from_constant(constant, /*require_const=*/ true);
297 assert(con_type != NULL, "type not found");
298 value = kit->gvn().transform(kit->makecon(con_type));
299 if (ft->is_valuetype() && !constant.as_object()->is_null_object()) {
300 // Null-free, treat as flattenable
301 is_flattenable = true;
302 }
303 } else {
304 // Load field value from memory
305 const TypePtr* adr_type = field_adr_type(base, offset, holder, decorators, kit->gvn());
306 Node* adr = kit->basic_plus_adr(base, ptr, offset);
307 BasicType bt = type2field[ft->basic_type()];
308 assert(is_java_primitive(bt) || adr->bottom_type()->is_ptr_to_narrowoop() == UseCompressedOops, "inconsistent");
309 const Type* val_type = Type::get_const_type(ft);
310 if (is_array) {
311 decorators |= IS_ARRAY;
312 }
313 value = kit->access_load_at(base, adr, adr_type, val_type, bt, decorators);
314 }
315 if (is_flattenable) {
316 // Loading a non-flattened but flattenable value type from memory
317 if (ft->as_value_klass()->is_scalarizable()) {
318 value = ValueTypeNode::make_from_oop(kit, value, ft->as_value_klass());
319 } else {
320 value = kit->null2default(value, ft->as_value_klass());
321 }
322 }
323 }
324 set_field_value(i, value);
325 }
326 }
327
328 void ValueTypeBaseNode::store_flattened(GraphKit* kit, Node* base, Node* ptr, ciInstanceKlass* holder, int holder_offset, DecoratorSet decorators) const {
329 // The value type is embedded into the object without an oop header. Subtract the
330 // offset of the first field to account for the missing header when storing the values.
331 if (holder == NULL) {
332 holder = value_klass();
333 }
334 holder_offset -= value_klass()->first_field_offset();
335 store(kit, base, ptr, holder, holder_offset, false, decorators);
336 }
337
338 void ValueTypeBaseNode::store(GraphKit* kit, Node* base, Node* ptr, ciInstanceKlass* holder, int holder_offset, bool deoptimize_on_exception, DecoratorSet decorators) const {
339 // Write field values to memory
340 for (uint i = 0; i < field_count(); ++i) {
341 int offset = holder_offset + field_offset(i);
342 Node* value = field_value(i);
343 ciType* ft = field_type(i);
344 if (field_is_flattened(i)) {
345 // Recursively store the flattened value type field
346 if (!value->is_ValueType()) {
347 assert(!kit->gvn().type(value)->maybe_null(), "should never be null");
348 value = ValueTypeNode::make_from_oop(kit, value, ft->as_value_klass());
349 }
350 value->as_ValueType()->store_flattened(kit, base, ptr, holder, offset, decorators);
351 } else {
352 // Store field value to memory
353 const TypePtr* adr_type = field_adr_type(base, offset, holder, decorators, kit->gvn());
354 Node* adr = kit->basic_plus_adr(base, ptr, offset);
355 BasicType bt = type2field[ft->basic_type()];
356 assert(is_java_primitive(bt) || adr->bottom_type()->is_ptr_to_narrowoop() == UseCompressedOops, "inconsistent");
357 const Type* val_type = Type::get_const_type(ft);
358 const TypeAryPtr* ary_type = kit->gvn().type(base)->isa_aryptr();
359 if (ary_type != NULL) {
360 decorators |= IS_ARRAY;
361 }
362 kit->access_store_at(base, adr, adr_type, value, val_type, bt, decorators, deoptimize_on_exception);
363 }
364 }
365 }
366
367 ValueTypeBaseNode* ValueTypeBaseNode::allocate(GraphKit* kit, bool deoptimize_on_exception, bool safe_for_replace) {
368 // Check if value type is already allocated
369 Node* null_ctl = kit->top();
370 Node* not_null_oop = kit->null_check_oop(get_oop(), &null_ctl);
371 if (null_ctl->is_top()) {
372 // Value type is allocated
373 return this;
374 }
375 assert(!is_allocated(&kit->gvn()), "should not be allocated");
376 RegionNode* region = new RegionNode(3);
377
378 // Oop is non-NULL, use it
379 region->init_req(1, kit->control());
380 PhiNode* oop = PhiNode::make(region, not_null_oop, value_ptr());
381 PhiNode* io = PhiNode::make(region, kit->i_o(), Type::ABIO);
382 PhiNode* mem = PhiNode::make(region, kit->merged_memory(), Type::MEMORY, TypePtr::BOTTOM);
383
384 {
385 // Oop is NULL, allocate and initialize buffer
386 PreserveJVMState pjvms(kit);
387 kit->set_control(null_ctl);
388 kit->kill_dead_locals();
389 ciValueKlass* vk = value_klass();
390 Node* klass_node = kit->makecon(TypeKlassPtr::make(vk));
391 Node* alloc_oop = kit->new_instance(klass_node, NULL, NULL, deoptimize_on_exception, this);
392 store(kit, alloc_oop, alloc_oop, vk, 0, deoptimize_on_exception);
393 region->init_req(2, kit->control());
394 oop ->init_req(2, alloc_oop);
395 io ->init_req(2, kit->i_o());
396 mem ->init_req(2, kit->merged_memory());
397 }
398
399 // Update GraphKit
400 kit->set_control(kit->gvn().transform(region));
401 kit->set_i_o(kit->gvn().transform(io));
402 kit->set_all_memory(kit->gvn().transform(mem));
403 kit->record_for_igvn(region);
404 kit->record_for_igvn(oop);
405 kit->record_for_igvn(io);
406 kit->record_for_igvn(mem);
407
408 // Use cloned ValueTypeNode to propagate oop from now on
409 Node* res_oop = kit->gvn().transform(oop);
410 ValueTypeBaseNode* vt = clone()->as_ValueTypeBase();
411 vt->set_oop(res_oop);
412 vt = kit->gvn().transform(vt)->as_ValueTypeBase();
413 if (safe_for_replace) {
414 kit->replace_in_map(this, vt);
415 }
416 return vt;
417 }
418
419 bool ValueTypeBaseNode::is_allocated(PhaseGVN* phase) const {
420 Node* oop = get_oop();
421 const Type* oop_type = (phase != NULL) ? phase->type(oop) : oop->bottom_type();
422 return !oop_type->maybe_null();
423 }
424
425 // When a call returns multiple values, it has several result
426 // projections, one per field. Replacing the result of the call by a
427 // value type node (after late inlining) requires that for each result
428 // projection, we find the corresponding value type field.
429 void ValueTypeBaseNode::replace_call_results(GraphKit* kit, Node* call, Compile* C) {
430 ciValueKlass* vk = value_klass();
431 for (DUIterator_Fast imax, i = call->fast_outs(imax); i < imax; i++) {
432 ProjNode* pn = call->fast_out(i)->as_Proj();
433 uint con = pn->_con;
434 if (con >= TypeFunc::Parms+1) {
435 uint field_nb = con - (TypeFunc::Parms+1);
436 int extra = 0;
437 for (uint j = 0; j < field_nb - extra; j++) {
438 ciField* f = vk->nonstatic_field_at(j);
439 BasicType bt = f->type()->basic_type();
440 if (bt == T_LONG || bt == T_DOUBLE) {
441 extra++;
442 }
443 }
444 ciField* f = vk->nonstatic_field_at(field_nb - extra);
445 Node* field = field_value_by_offset(f->offset(), true);
446 if (field->is_ValueType()) {
447 field = field->as_ValueType()->allocate(kit)->get_oop();
448 }
449 C->gvn_replace_by(pn, field);
450 C->initial_gvn()->hash_delete(pn);
451 pn->set_req(0, C->top());
452 --i; --imax;
453 }
454 }
455 }
456
457 ValueTypeNode* ValueTypeNode::make_uninitialized(PhaseGVN& gvn, ciValueKlass* vk) {
458 // Create a new ValueTypeNode with uninitialized values and NULL oop
459 return new ValueTypeNode(vk, gvn.zerocon(T_VALUETYPE));
460 }
461
462 Node* ValueTypeNode::default_oop(PhaseGVN& gvn, ciValueKlass* vk) {
463 // Returns the constant oop of the default value type allocation
464 return gvn.makecon(TypeInstPtr::make(vk->default_value_instance()));
465 }
466
467 ValueTypeNode* ValueTypeNode::make_default(PhaseGVN& gvn, ciValueKlass* vk) {
468 // Create a new ValueTypeNode with default values
469 ValueTypeNode* vt = new ValueTypeNode(vk, default_oop(gvn, vk));
470 for (uint i = 0; i < vt->field_count(); ++i) {
471 ciType* field_type = vt->field_type(i);
472 Node* value = NULL;
473 if (field_type->is_valuetype() && vt->field_is_flattenable(i)) {
474 ciValueKlass* field_klass = field_type->as_value_klass();
475 if (field_klass->is_scalarizable() || vt->field_is_flattened(i)) {
476 value = ValueTypeNode::make_default(gvn, field_klass);
477 } else {
478 value = default_oop(gvn, field_klass);
479 }
480 } else {
481 value = gvn.zerocon(field_type->basic_type());
482 }
483 vt->set_field_value(i, value);
484 }
485 vt = gvn.transform(vt)->as_ValueType();
486 assert(vt->is_default(gvn), "must be the default value type");
487 return vt;
488 }
489
490 bool ValueTypeNode::is_default(PhaseGVN& gvn) const {
491 for (uint i = 0; i < field_count(); ++i) {
492 Node* value = field_value(i);
493 if (!gvn.type(value)->is_zero_type() &&
494 !(value->is_ValueType() && value->as_ValueType()->is_default(gvn)) &&
495 !(field_type(i)->is_valuetype() && value == default_oop(gvn, field_type(i)->as_value_klass()))) {
496 return false;
497 }
498 }
499 return true;
500 }
501
502 ValueTypeNode* ValueTypeNode::make_from_oop(GraphKit* kit, Node* oop, ciValueKlass* vk) {
503 PhaseGVN& gvn = kit->gvn();
504
505 // Create and initialize a ValueTypeNode by loading all field
506 // values from a heap-allocated version and also save the oop.
507 ValueTypeNode* vt = new ValueTypeNode(vk, oop);
508
509 if (oop->isa_ValueTypePtr()) {
510 // Can happen with late inlining
511 ValueTypePtrNode* vtptr = oop->as_ValueTypePtr();
512 vt->set_oop(vtptr->get_oop());
513 for (uint i = Oop+1; i < vtptr->req(); ++i) {
514 vt->init_req(i, vtptr->in(i));
515 }
516 } else if (gvn.type(oop)->maybe_null()) {
517 // Add a null check because the oop may be null
518 Node* null_ctl = kit->top();
519 Node* not_null_oop = kit->null_check_oop(oop, &null_ctl);
520 if (kit->stopped()) {
521 // Constant null
522 kit->set_control(null_ctl);
523 return make_default(gvn, vk);
524 }
525 vt->set_oop(not_null_oop);
526 vt->load(kit, not_null_oop, not_null_oop, vk, /* holder_offset */ 0);
527
528 if (null_ctl != kit->top()) {
529 // Return default value type if oop is null
530 ValueTypeNode* def = make_default(gvn, vk);
531 Node* region = new RegionNode(3);
532 region->init_req(1, kit->control());
533 region->init_req(2, null_ctl);
534
535 vt = vt->clone_with_phis(&gvn, region)->as_ValueType();
536 vt->merge_with(&gvn, def, 2, true);
537 kit->set_control(gvn.transform(region));
538 }
539 } else {
540 // Oop can never be null
541 Node* init_ctl = kit->control();
542 vt->load(kit, oop, oop, vk, /* holder_offset */ 0);
543 assert(init_ctl != kit->control() || !gvn.type(oop)->is_valuetypeptr() || oop->is_Con() || oop->Opcode() == Op_ValueTypePtr ||
544 AllocateNode::Ideal_allocation(oop, &gvn) != NULL || vt->is_loaded(&gvn) == oop, "value type should be loaded");
545 }
546
547 assert(vt->is_allocated(&gvn), "value type should be allocated");
548 return gvn.transform(vt)->as_ValueType();
549 }
550
551 // GraphKit wrapper for the 'make_from_flattened' method
552 ValueTypeNode* ValueTypeNode::make_from_flattened(GraphKit* kit, ciValueKlass* vk, Node* obj, Node* ptr, ciInstanceKlass* holder, int holder_offset, DecoratorSet decorators) {
553 // Create and initialize a ValueTypeNode by loading all field values from
554 // a flattened value type field at 'holder_offset' or from a value type array.
555 ValueTypeNode* vt = make_uninitialized(kit->gvn(), vk);
556 // The value type is flattened into the object without an oop header. Subtract the
557 // offset of the first field to account for the missing header when loading the values.
558 holder_offset -= vk->first_field_offset();
559 vt->load(kit, obj, ptr, holder, holder_offset, decorators);
560 assert(vt->is_loaded(&kit->gvn()) != obj, "holder oop should not be used as flattened value type oop");
561 return kit->gvn().transform(vt)->as_ValueType();
562 }
563
564 ValueTypeNode* ValueTypeNode::make_from_multi(GraphKit* kit, MultiNode* multi, ExtendedSignature& sig, ciValueKlass* vk, uint& base_input, bool in) {
565 ValueTypeNode* vt = ValueTypeNode::make_uninitialized(kit->gvn(), vk);
566 vt->initialize_fields(kit, multi, sig, base_input, 0, in);
567 return kit->gvn().transform(vt)->as_ValueType();
568 }
569
570 ValueTypeNode* ValueTypeNode::make_larval(GraphKit* kit, bool allocate) const {
571 ciValueKlass* vk = value_klass();
572 ValueTypeNode* res = clone()->as_ValueType();
573 if (allocate) {
574 Node* klass_node = kit->makecon(TypeKlassPtr::make(vk));
575 Node* alloc_oop = kit->new_instance(klass_node, NULL, NULL, false);
576 AllocateNode* alloc = AllocateNode::Ideal_allocation(alloc_oop, &kit->gvn());
577 alloc->_larval = true;
578
579 store(kit, alloc_oop, alloc_oop, vk, 0, false);
580 res->set_oop(alloc_oop);
581 }
582 res->set_type(TypeValueType::make(vk, true));
583 res = kit->gvn().transform(res)->as_ValueType();
584 return res;
585 }
586
587 ValueTypeNode* ValueTypeNode::finish_larval(GraphKit* kit) const {
588 Node* obj = get_oop();
589 Node* mark_addr = kit->basic_plus_adr(obj, oopDesc::mark_offset_in_bytes());
590 Node* mark = kit->make_load(NULL, mark_addr, TypeX_X, TypeX_X->basic_type(), MemNode::unordered);
591 mark = kit->gvn().transform(new AndXNode(mark, kit->MakeConX(~markOopDesc::larval_mask_in_place)));
592 kit->store_to_memory(kit->control(), mark_addr, mark, TypeX_X->basic_type(), kit->gvn().type(mark_addr)->is_ptr(), MemNode::unordered);
593
594 ciValueKlass* vk = value_klass();
595 ValueTypeNode* res = clone()->as_ValueType();
596 res->set_type(TypeValueType::make(vk, false));
597 res = kit->gvn().transform(res)->as_ValueType();
598 return res;
599 }
600
601 Node* ValueTypeNode::is_loaded(PhaseGVN* phase, ciValueKlass* vk, Node* base, int holder_offset) {
602 if (vk == NULL) {
603 vk = value_klass();
604 }
605 if (field_count() == 0) {
606 assert(is_allocated(phase), "must be allocated");
607 return get_oop();
608 }
609 for (uint i = 0; i < field_count(); ++i) {
610 int offset = holder_offset + field_offset(i);
611 Node* value = field_value(i);
612 if (value->is_ValueType()) {
613 ValueTypeNode* vt = value->as_ValueType();
614 if (field_is_flattened(i)) {
615 // Check value type field load recursively
616 base = vt->is_loaded(phase, vk, base, offset - vt->value_klass()->first_field_offset());
617 if (base == NULL) {
618 return NULL;
619 }
620 continue;
621 } else {
622 value = vt->get_oop();
623 if (value->Opcode() == Op_CastPP) {
624 // Skip CastPP
625 value = value->in(1);
626 }
627 }
628 }
629 if (value->isa_DecodeN()) {
630 // Skip DecodeN
631 value = value->in(1);
632 }
633 if (value->isa_Load()) {
634 // Check if base and offset of field load matches value type layout
635 intptr_t loffset = 0;
636 Node* lbase = AddPNode::Ideal_base_and_offset(value->in(MemNode::Address), phase, loffset);
637 if (lbase == NULL || (lbase != base && base != NULL) || loffset != offset) {
638 return NULL;
639 } else if (base == NULL) {
640 // Set base and check if pointer type matches
641 base = lbase;
642 const TypeInstPtr* vtptr = phase->type(base)->isa_instptr();
643 if (vtptr == NULL || !vtptr->klass()->equals(vk)) {
644 return NULL;
645 }
646 }
647 } else {
648 return NULL;
649 }
650 }
651 return base;
652 }
653
654 Node* ValueTypeNode::allocate_fields(GraphKit* kit) {
655 ValueTypeNode* vt = clone()->as_ValueType();
656 for (uint i = 0; i < field_count(); i++) {
657 ValueTypeNode* value = field_value(i)->isa_ValueType();
658 if (field_is_flattened(i)) {
659 // Flattened value type field
660 vt->set_field_value(i, value->allocate_fields(kit));
661 } else if (value != NULL){
662 // Non-flattened value type field
663 vt->set_field_value(i, value->allocate(kit));
664 }
665 }
666 vt = kit->gvn().transform(vt)->as_ValueType();
667 kit->replace_in_map(this, vt);
668 return vt;
669 }
670
671 Node* ValueTypeNode::tagged_klass(ciValueKlass* vk, PhaseGVN& gvn) {
672 const TypeKlassPtr* tk = TypeKlassPtr::make(vk);
673 intptr_t bits = tk->get_con();
674 set_nth_bit(bits, 0);
675 return gvn.makecon(TypeRawPtr::make((address)bits));
676 }
677
678 void ValueTypeNode::pass_fields(GraphKit* kit, Node* n, ExtendedSignature& sig, uint& base_input, int base_offset) {
679 for (uint i = 0; i < field_count(); i++) {
680 int sig_offset = (*sig)._offset;
681 uint idx = field_index(sig_offset - base_offset);
682 Node* arg = field_value(idx);
683
684 if (field_is_flattened(idx)) {
685 // Flattened value type field
686 ValueTypeNode* vt = arg->as_ValueType();
687 vt->pass_fields(kit, n, sig, base_input, sig_offset - vt->value_klass()->first_field_offset());
688 } else {
689 if (arg->is_ValueType()) {
690 // Non-flattened value type field
691 ValueTypeNode* vt = arg->as_ValueType();
692 assert(n->Opcode() != Op_Return || vt->is_allocated(&kit->gvn()), "value type field should be allocated on return");
693 arg = vt->allocate(kit)->get_oop();
694 }
695 // Initialize call/return arguments
696 BasicType bt = field_type(i)->basic_type();
697 n->init_req(base_input++, arg);
698 if (type2size[bt] == 2) {
699 n->init_req(base_input++, kit->top());
700 }
701 // Skip reserved arguments
702 while (SigEntry::next_is_reserved(sig, bt)) {
703 n->init_req(base_input++, kit->top());
704 if (type2size[bt] == 2) {
705 n->init_req(base_input++, kit->top());
706 }
707 }
708 }
709 }
710 }
711
712 void ValueTypeNode::initialize_fields(GraphKit* kit, MultiNode* multi, ExtendedSignature& sig, uint& base_input, int base_offset, bool in) {
713 PhaseGVN& gvn = kit->gvn();
714 for (uint i = 0; i < field_count(); i++) {
715 int sig_offset = (*sig)._offset;
716 uint idx = field_index(sig_offset - base_offset);
717 ciType* type = field_type(idx);
718
719 Node* parm = NULL;
720 if (field_is_flattened(idx)) {
721 // Flattened value type field
722 ValueTypeNode* vt = ValueTypeNode::make_uninitialized(gvn, type->as_value_klass());
723 vt->initialize_fields(kit, multi, sig, base_input, sig_offset - type->as_value_klass()->first_field_offset(), in);
724 parm = gvn.transform(vt);
725 } else {
726 if (multi->is_Start()) {
727 assert(in, "return from start?");
728 parm = gvn.transform(new ParmNode(multi->as_Start(), base_input));
729 } else if (in) {
730 parm = multi->as_Call()->in(base_input);
731 } else {
732 parm = gvn.transform(new ProjNode(multi->as_Call(), base_input));
733 }
734 if (field_is_flattenable(idx)) {
735 // Non-flattened but flattenable value type
736 if (type->as_value_klass()->is_scalarizable()) {
737 parm = ValueTypeNode::make_from_oop(kit, parm, type->as_value_klass());
738 } else {
739 parm = kit->null2default(parm, type->as_value_klass());
740 }
741 }
742 base_input += type2size[type->basic_type()];
743 // Skip reserved arguments
744 BasicType bt = type->basic_type();
745 while (SigEntry::next_is_reserved(sig, bt)) {
746 base_input += type2size[bt];
747 }
748 }
749 assert(parm != NULL, "should never be null");
750 set_field_value(idx, parm);
751 gvn.record_for_igvn(parm);
752 }
753 }
754
755 Node* ValueTypeNode::Ideal(PhaseGVN* phase, bool can_reshape) {
756 Node* oop = get_oop();
757 if (is_default(*phase) && (!oop->is_Con() || phase->type(oop)->is_zero_type())) {
758 // Use the pre-allocated oop for default value types
759 set_oop(default_oop(*phase, value_klass()));
760 return this;
761 } else if (oop->isa_ValueTypePtr()) {
762 // Can happen with late inlining
763 ValueTypePtrNode* vtptr = oop->as_ValueTypePtr();
764 set_oop(vtptr->get_oop());
765 for (uint i = Oop+1; i < vtptr->req(); ++i) {
766 set_req(i, vtptr->in(i));
767 }
768 return this;
769 }
770
771 if (!is_allocated(phase)) {
772 // Save base oop if fields are loaded from memory and the value
773 // type is not buffered (in this case we should not use the oop).
774 Node* base = is_loaded(phase);
775 if (base != NULL) {
776 set_oop(base);
777 assert(is_allocated(phase), "should now be allocated");
778 return this;
779 }
780 }
781
782 if (can_reshape) {
783 PhaseIterGVN* igvn = phase->is_IterGVN();
784
785 if (is_default(*phase)) {
786 // Search for users of the default value type
787 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
788 Node* user = fast_out(i);
789 AllocateNode* alloc = user->isa_Allocate();
790 if (alloc != NULL && alloc->result_cast() != NULL && alloc->in(AllocateNode::ValueNode) == this) {
791 // Found an allocation of the default value type.
792 // If the code in StoreNode::Identity() that removes useless stores was not yet
793 // executed or ReduceFieldZeroing is disabled, there can still be initializing
794 // stores (only zero-type or default value stores, because value types are immutable).
795 Node* res = alloc->result_cast();
796 for (DUIterator_Fast jmax, j = res->fast_outs(jmax); j < jmax; j++) {
797 AddPNode* addp = res->fast_out(j)->isa_AddP();
798 if (addp != NULL) {
799 for (DUIterator_Fast kmax, k = addp->fast_outs(kmax); k < kmax; k++) {
800 StoreNode* store = addp->fast_out(k)->isa_Store();
801 if (store != NULL && store->outcnt() != 0) {
802 // Remove the useless store
803 igvn->replace_in_uses(store, store->in(MemNode::Memory));
804 }
805 }
806 }
807 }
808 // Replace allocation by pre-allocated oop
809 igvn->replace_node(res, default_oop(*phase, value_klass()));
810 } else if (user->is_ValueType()) {
811 // Add value type user to worklist to give it a chance to get optimized as well
812 igvn->_worklist.push(user);
813 }
814 }
815 }
816
817 if (is_allocated(igvn)) {
818 // Value type is heap allocated, search for safepoint uses
819 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
820 Node* out = fast_out(i);
821 if (out->is_SafePoint()) {
822 // Let SafePointNode::Ideal() take care of re-wiring the
823 // safepoint to the oop input instead of the value type node.
824 igvn->rehash_node_delayed(out);
825 }
826 }
827 }
828 }
829 return NULL;
830 }
831
832 // Search for multiple allocations of this value type
833 // and try to replace them by dominating allocations.
834 void ValueTypeNode::remove_redundant_allocations(PhaseIterGVN* igvn, PhaseIdealLoop* phase) {
835 assert(EliminateAllocations, "allocation elimination should be enabled");
836 // Search for allocations of this value type
837 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
838 AllocateNode* alloc = fast_out(i)->isa_Allocate();
839 if (alloc != NULL && alloc->result_cast() != NULL && alloc->in(AllocateNode::ValueNode) == this) {
840 assert(!is_default(*igvn), "default value type allocation");
841 Node* res = alloc->result_cast();
842 Node* res_dom = NULL;
843 if (is_allocated(igvn)) {
844 // The value type is already allocated but still connected to an AllocateNode.
845 // This can happen with late inlining when we first allocate a value type argument
846 // but later decide to inline the call with the callee code also allocating.
847 res_dom = get_oop();
848 } else {
849 // Search for a dominating allocation of the same value type
850 for (DUIterator_Fast jmax, j = fast_outs(jmax); j < jmax; j++) {
851 AllocateNode* alloc_dom = fast_out(j)->isa_Allocate();
852 if (alloc_dom != NULL && alloc != alloc_dom && alloc_dom->result_cast() != NULL &&
853 alloc_dom->in(AllocateNode::ValueNode) == this) {
854 assert(alloc->in(AllocateNode::KlassNode) == alloc_dom->in(AllocateNode::KlassNode), "klasses should match");
855 if (phase->is_dominator(alloc_dom->result_cast()->in(0), res->in(0))) {
856 res_dom = alloc_dom->result_cast();
857 break;
858 }
859 }
860 }
861 }
862 if (res_dom != NULL) {
863 // Move users to dominating allocation
864 igvn->replace_node(res, res_dom);
865 // The result of the dominated allocation is now unused and will be
866 // removed later in AllocateNode::Ideal() to not confuse loop opts.
867 igvn->record_for_igvn(alloc);
868 #ifdef ASSERT
869 if (PrintEliminateAllocations) {
870 tty->print("++++ Eliminated: %d Allocate ", alloc->_idx);
871 dump_spec(tty);
872 tty->cr();
873 }
874 #endif
875 }
876 }
877 }
878
879 // Process users
880 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
881 Node* out = fast_out(i);
882 if (out->is_ValueType()) {
883 // Recursively process value type users
884 out->as_ValueType()->remove_redundant_allocations(igvn, phase);
885 } else if (out->isa_Allocate() != NULL) {
886 // Allocate users should be linked
887 assert(out->in(AllocateNode::ValueNode) == this, "should be linked");
888 } else {
889 #ifdef ASSERT
890 // The value type should not have any other users at this time
891 out->dump();
892 assert(false, "unexpected user of value type");
893 #endif
894 }
895 }
896 }
897
898 ValueTypePtrNode* ValueTypePtrNode::make_from_value_type(GraphKit* kit, ValueTypeNode* vt, bool deoptimize_on_exception) {
899 Node* oop = vt->allocate(kit, deoptimize_on_exception)->get_oop();
900 ValueTypePtrNode* vtptr = new ValueTypePtrNode(vt->value_klass(), oop);
901 for (uint i = Oop+1; i < vt->req(); i++) {
902 vtptr->init_req(i, vt->in(i));
903 }
904 return kit->gvn().transform(vtptr)->as_ValueTypePtr();
905 }
906
907 ValueTypePtrNode* ValueTypePtrNode::make_from_oop(GraphKit* kit, Node* oop) {
908 // Create and initialize a ValueTypePtrNode by loading all field
909 // values from a heap-allocated version and also save the oop.
910 ciValueKlass* vk = kit->gvn().type(oop)->value_klass();
911 ValueTypePtrNode* vtptr = new ValueTypePtrNode(vk, oop);
912 vtptr->load(kit, oop, oop, vk);
913 return kit->gvn().transform(vtptr)->as_ValueTypePtr();
914 }