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 uint i = 0;
169 for (; i < field_count() && field_offset(i) != offset; i++) { }
170 assert(i < field_count(), "field not found");
171 set_field_value(i, value);
172 }
173
174 int ValueTypeBaseNode::field_offset(uint index) const {
175 assert(index < field_count(), "index out of bounds");
176 return value_klass()->declared_nonstatic_field_at(index)->offset();
177 }
178
179 ciType* ValueTypeBaseNode::field_type(uint index) const {
180 assert(index < field_count(), "index out of bounds");
181 return value_klass()->declared_nonstatic_field_at(index)->type();
182 }
183
184 bool ValueTypeBaseNode::field_is_flattened(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_flattened() || field->type()->is_valuetype(), "must be a value type");
188 return field->is_flattened();
189 }
190
191 bool ValueTypeBaseNode::field_is_flattenable(uint index) const {
192 assert(index < field_count(), "index out of bounds");
193 ciField* field = value_klass()->declared_nonstatic_field_at(index);
194 assert(!field->is_flattenable() || field->type()->is_valuetype(), "must be a value type");
195 return field->is_flattenable();
196 }
197
198 int ValueTypeBaseNode::make_scalar_in_safepoint(Unique_Node_List& worklist, SafePointNode* sfpt, Node* root, PhaseGVN* gvn) {
199 ciValueKlass* vk = value_klass();
200 uint nfields = vk->nof_nonstatic_fields();
201 JVMState* jvms = sfpt->jvms();
202 int start = jvms->debug_start();
203 int end = jvms->debug_end();
204 // Replace safepoint edge by SafePointScalarObjectNode and add field values
205 assert(jvms != NULL, "missing JVMS");
206 uint first_ind = (sfpt->req() - jvms->scloff());
207 SafePointScalarObjectNode* sobj = new SafePointScalarObjectNode(value_ptr(),
208 #ifdef ASSERT
209 NULL,
210 #endif
211 first_ind, nfields);
212 sobj->init_req(0, root);
213 // Iterate over the value type fields in order of increasing
214 // offset and add the field values to the safepoint.
215 for (uint j = 0; j < nfields; ++j) {
216 int offset = vk->nonstatic_field_at(j)->offset();
217 Node* value = field_value_by_offset(offset, true /* include flattened value type fields */);
218 if (value->is_ValueType()) {
219 if (value->as_ValueType()->is_allocated(gvn)) {
220 value = value->as_ValueType()->get_oop();
221 } else {
222 // Add non-flattened value type field to the worklist to process later
223 worklist.push(value);
224 }
225 }
226 sfpt->add_req(value);
227 }
228 jvms->set_endoff(sfpt->req());
229 if (gvn != NULL) {
230 sobj = gvn->transform(sobj)->as_SafePointScalarObject();
231 gvn->igvn_rehash_node_delayed(sfpt);
232 }
233 return sfpt->replace_edges_in_range(this, sobj, start, end);
234 }
235
236 void ValueTypeBaseNode::make_scalar_in_safepoints(Node* root, PhaseGVN* gvn) {
237 // Process all safepoint uses and scalarize value type
238 Unique_Node_List worklist;
239 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
240 Node* u = fast_out(i);
241 if (u->is_SafePoint() && !u->is_CallLeaf() && (!u->is_Call() || u->as_Call()->has_debug_use(this))) {
242 SafePointNode* sfpt = u->as_SafePoint();
243 Node* in_oop = get_oop();
244 const Type* oop_type = in_oop->bottom_type();
245 assert(Opcode() == Op_ValueTypePtr || !isa_ValueType()->is_allocated(gvn), "already heap allocated value types should be linked directly");
246 int nb = make_scalar_in_safepoint(worklist, sfpt, root, gvn);
247 --i; imax -= nb;
248 }
249 }
250 // Now scalarize non-flattened fields
251 for (uint i = 0; i < worklist.size(); ++i) {
252 Node* vt = worklist.at(i);
253 vt->as_ValueType()->make_scalar_in_safepoints(root, gvn);
254 }
255 }
256
257 void ValueTypeBaseNode::initialize(GraphKit* kit, MultiNode* multi, ciValueKlass* vk, int base_offset, uint& base_input, bool in) {
258 assert(base_offset >= 0, "offset in value type must be positive");
259 assert(base_input >= TypeFunc::Parms, "invalid base input");
260 PhaseGVN& gvn = kit->gvn();
261 for (uint i = 0; i < field_count(); i++) {
262 ciType* ft = field_type(i);
263 int offset = base_offset + field_offset(i);
264 if (field_is_flattened(i)) {
265 // Flattened value type field
266 ValueTypeNode* vt = ValueTypeNode::make_uninitialized(gvn, ft->as_value_klass());
267 uint base = base_input;
268 vt->initialize(kit, multi, vk, offset - value_klass()->first_field_offset(), base, in);
269 set_field_value(i, gvn.transform(vt));
270 } else {
271 int j = 0; int extra = 0;
272 for (; j < vk->nof_nonstatic_fields(); j++) {
273 ciField* f = vk->nonstatic_field_at(j);
274 if (offset == f->offset()) {
275 assert(f->type() == ft, "inconsistent field type");
276 break;
277 }
278 BasicType bt = f->type()->basic_type();
279 if (bt == T_LONG || bt == T_DOUBLE) {
280 extra++;
281 }
282 }
283 assert(j != vk->nof_nonstatic_fields(), "must find");
284 Node* parm = NULL;
285 int index = base_input + j + extra;
286
287 ciMethod* method = multi->is_Start()? kit->C->method() : multi->as_CallStaticJava()->method();
288 SigEntry res_entry = method->get_Method()->get_res_entry();
289 if (res_entry._offset != -1 && (index - TypeFunc::Parms) >= res_entry._offset) {
290 // Skip reserved entry
291 index += type2size[res_entry._bt];
292 }
293 if (multi->is_Start()) {
294 assert(in, "return from start?");
295 parm = gvn.transform(new ParmNode(multi->as_Start(), index));
296 } else {
297 if (in) {
298 parm = multi->as_Call()->in(index);
299 } else {
300 parm = gvn.transform(new ProjNode(multi->as_Call(), index));
301 }
302 }
303
304 if (field_is_flattenable(i)) {
305 // Non-flattened but flattenable value type
306 if (ft->as_value_klass()->is_scalarizable()) {
307 parm = ValueTypeNode::make_from_oop(kit, parm, ft->as_value_klass());
308 } else {
309 parm = kit->null2default(parm, ft->as_value_klass());
310 }
311 }
312
313 set_field_value(i, parm);
314 // Record all these guys for later GVN.
315 gvn.record_for_igvn(parm);
316 }
317 }
318 base_input += vk->value_arg_slots();
319 }
320
321 const TypePtr* ValueTypeBaseNode::field_adr_type(Node* base, int offset, ciInstanceKlass* holder, PhaseGVN& gvn) const {
322 const TypeAryPtr* ary_type = gvn.type(base)->isa_aryptr();
323 const TypePtr* adr_type = NULL;
324 bool is_array = ary_type != NULL;
325 if (is_array) {
326 // In the case of a flattened value type array, each field has its own slice
327 adr_type = ary_type->with_field_offset(offset)->add_offset(Type::OffsetBot);
328 } else {
329 ciField* field = holder->get_field_by_offset(offset, false);
330 assert(field != NULL, "field not found");
331 adr_type = gvn.C->alias_type(field)->adr_type();
332 }
333 return adr_type;
334 }
335
336 void ValueTypeBaseNode::load(GraphKit* kit, Node* base, Node* ptr, ciInstanceKlass* holder, int holder_offset) {
337 // Initialize the value type by loading its field values from
338 // memory and adding the values as input edges to the node.
339 for (uint i = 0; i < field_count(); ++i) {
340 int offset = holder_offset + field_offset(i);
341 Node* value = NULL;
342 ciType* ft = field_type(i);
343 if (field_is_flattened(i)) {
344 // Recursively load the flattened value type field
345 value = ValueTypeNode::make_from_flattened(kit, ft->as_value_klass(), base, ptr, holder, offset);
346 } else {
347 const TypeOopPtr* oop_ptr = kit->gvn().type(base)->isa_oopptr();
348 bool is_array = (oop_ptr->isa_aryptr() != NULL);
349 if (base->is_Con() && !is_array) {
350 // If the oop to the value type is constant (static final field), we can
351 // also treat the fields as constants because the value type is immutable.
352 ciObject* constant_oop = oop_ptr->const_oop();
353 ciField* field = holder->get_field_by_offset(offset, false);
354 assert(field != NULL, "field not found");
355 ciConstant constant = constant_oop->as_instance()->field_value(field);
356 const Type* con_type = Type::make_from_constant(constant, /*require_const=*/ true);
357 assert(con_type != NULL, "type not found");
358 value = kit->gvn().transform(kit->makecon(con_type));
359 } else {
360 // Load field value from memory
361 const TypePtr* adr_type = field_adr_type(base, offset, holder, kit->gvn());
362 Node* adr = kit->basic_plus_adr(base, ptr, offset);
363 BasicType bt = type2field[ft->basic_type()];
364 assert(is_java_primitive(bt) || adr->bottom_type()->is_ptr_to_narrowoop() == UseCompressedOops, "inconsistent");
365 const Type* val_type = Type::get_const_type(ft);
366 DecoratorSet decorators = IN_HEAP | MO_UNORDERED;
367 if (is_array) {
368 decorators |= IS_ARRAY;
369 }
370 value = kit->access_load_at(base, adr, adr_type, val_type, bt, decorators);
371 }
372 if (field_is_flattenable(i)) {
373 // Loading a non-flattened but flattenable value type from memory
374 if (ft->as_value_klass()->is_scalarizable()) {
375 value = ValueTypeNode::make_from_oop(kit, value, ft->as_value_klass());
376 } else {
377 value = kit->null2default(value, ft->as_value_klass());
378 }
379 }
380 }
381 set_field_value(i, value);
382 }
383 }
384
385 void ValueTypeBaseNode::store_flattened(GraphKit* kit, Node* base, Node* ptr, ciInstanceKlass* holder, int holder_offset) const {
386 // The value type is embedded into the object without an oop header. Subtract the
387 // offset of the first field to account for the missing header when storing the values.
388 if (holder == NULL) {
389 holder = value_klass();
390 }
391 holder_offset -= value_klass()->first_field_offset();
392 store(kit, base, ptr, holder, holder_offset);
393 }
394
395 void ValueTypeBaseNode::store(GraphKit* kit, Node* base, Node* ptr, ciInstanceKlass* holder, int holder_offset, bool deoptimize_on_exception) const {
396 // Write field values to memory
397 for (uint i = 0; i < field_count(); ++i) {
398 int offset = holder_offset + field_offset(i);
399 Node* value = field_value(i);
400 ciType* ft = field_type(i);
401 if (field_is_flattened(i)) {
402 // Recursively store the flattened value type field
403 if (!value->is_ValueType()) {
404 assert(!kit->gvn().type(value)->maybe_null(), "should never be null");
405 value = ValueTypeNode::make_from_oop(kit, value, ft->as_value_klass());
406 }
407 value->as_ValueType()->store_flattened(kit, base, ptr, holder, offset);
408 } else {
409 // Store field value to memory
410 const TypePtr* adr_type = field_adr_type(base, offset, holder, kit->gvn());
411 Node* adr = kit->basic_plus_adr(base, ptr, offset);
412 BasicType bt = type2field[ft->basic_type()];
413 assert(is_java_primitive(bt) || adr->bottom_type()->is_ptr_to_narrowoop() == UseCompressedOops, "inconsistent");
414 const Type* val_type = Type::get_const_type(ft);
415 const TypeAryPtr* ary_type = kit->gvn().type(base)->isa_aryptr();
416 DecoratorSet decorators = IN_HEAP | MO_UNORDERED;
417 if (ary_type != NULL) {
418 decorators |= IS_ARRAY;
419 }
420 kit->access_store_at(base, adr, adr_type, value, val_type, bt, decorators, deoptimize_on_exception);
421 }
422 }
423 }
424
425 ValueTypeBaseNode* ValueTypeBaseNode::allocate(GraphKit* kit, bool deoptimize_on_exception) {
426 // Check if value type is already allocated
427 Node* null_ctl = kit->top();
428 Node* not_null_oop = kit->null_check_oop(get_oop(), &null_ctl);
429 if (null_ctl->is_top()) {
430 // Value type is allocated
431 return this;
432 }
433 assert(!is_allocated(&kit->gvn()), "should not be allocated");
434 RegionNode* region = new RegionNode(3);
435
436 // Oop is non-NULL, use it
437 region->init_req(1, kit->control());
438 PhiNode* oop = PhiNode::make(region, not_null_oop, value_ptr());
439 PhiNode* io = PhiNode::make(region, kit->i_o(), Type::ABIO);
440 PhiNode* mem = PhiNode::make(region, kit->merged_memory(), Type::MEMORY, TypePtr::BOTTOM);
441
442 {
443 // Oop is NULL, allocate and initialize buffer
444 PreserveJVMState pjvms(kit);
445 kit->set_control(null_ctl);
446 kit->kill_dead_locals();
447 ciValueKlass* vk = value_klass();
448 Node* klass_node = kit->makecon(TypeKlassPtr::make(vk));
449 Node* alloc_oop = kit->new_instance(klass_node, NULL, NULL, deoptimize_on_exception, this);
450 store(kit, alloc_oop, alloc_oop, vk, 0, deoptimize_on_exception);
451 region->init_req(2, kit->control());
452 oop ->init_req(2, alloc_oop);
453 io ->init_req(2, kit->i_o());
454 mem ->init_req(2, kit->merged_memory());
455 }
456
457 // Update GraphKit
458 kit->set_control(kit->gvn().transform(region));
459 kit->set_i_o(kit->gvn().transform(io));
460 kit->set_all_memory(kit->gvn().transform(mem));
461 kit->record_for_igvn(region);
462 kit->record_for_igvn(oop);
463 kit->record_for_igvn(io);
464 kit->record_for_igvn(mem);
465
466 // Use cloned ValueTypeNode to propagate oop from now on
467 Node* res_oop = kit->gvn().transform(oop);
468 ValueTypeBaseNode* vt = clone()->as_ValueTypeBase();
469 vt->set_oop(res_oop);
470 vt = kit->gvn().transform(vt)->as_ValueTypeBase();
471 kit->replace_in_map(this, vt);
472 return vt;
473 }
474
475 bool ValueTypeBaseNode::is_allocated(PhaseGVN* phase) const {
476 Node* oop = get_oop();
477 const Type* oop_type = (phase != NULL) ? phase->type(oop) : oop->bottom_type();
478 return !oop_type->maybe_null();
479 }
480
481 // When a call returns multiple values, it has several result
482 // projections, one per field. Replacing the result of the call by a
483 // value type node (after late inlining) requires that for each result
484 // projection, we find the corresponding value type field.
485 void ValueTypeBaseNode::replace_call_results(GraphKit* kit, Node* call, Compile* C) {
486 ciValueKlass* vk = value_klass();
487 for (DUIterator_Fast imax, i = call->fast_outs(imax); i < imax; i++) {
488 ProjNode* pn = call->fast_out(i)->as_Proj();
489 uint con = pn->_con;
490 if (con >= TypeFunc::Parms+1) {
491 uint field_nb = con - (TypeFunc::Parms+1);
492 int extra = 0;
493 for (uint j = 0; j < field_nb - extra; j++) {
494 ciField* f = vk->nonstatic_field_at(j);
495 BasicType bt = f->type()->basic_type();
496 if (bt == T_LONG || bt == T_DOUBLE) {
497 extra++;
498 }
499 }
500 ciField* f = vk->nonstatic_field_at(field_nb - extra);
501 Node* field = field_value_by_offset(f->offset(), true);
502 if (field->is_ValueType()) {
503 assert(f->is_flattened(), "should be flattened");
504 field = field->as_ValueType()->allocate(kit)->get_oop();
505 }
506 C->gvn_replace_by(pn, field);
507 C->initial_gvn()->hash_delete(pn);
508 pn->set_req(0, C->top());
509 --i; --imax;
510 }
511 }
512 }
513
514 ValueTypeNode* ValueTypeNode::make_uninitialized(PhaseGVN& gvn, ciValueKlass* vk) {
515 // Create a new ValueTypeNode with uninitialized values and NULL oop
516 return new ValueTypeNode(vk, gvn.zerocon(T_VALUETYPE));
517 }
518
519 Node* ValueTypeNode::default_oop(PhaseGVN& gvn, ciValueKlass* vk) {
520 // Returns the constant oop of the default value type allocation
521 return gvn.makecon(TypeInstPtr::make(vk->default_value_instance()));
522 }
523
524 ValueTypeNode* ValueTypeNode::make_default(PhaseGVN& gvn, ciValueKlass* vk) {
525 // Create a new ValueTypeNode with default values
526 ValueTypeNode* vt = new ValueTypeNode(vk, default_oop(gvn, vk));
527 for (uint i = 0; i < vt->field_count(); ++i) {
528 ciType* field_type = vt->field_type(i);
529 Node* value = NULL;
530 if (field_type->is_valuetype() && vt->field_is_flattenable(i)) {
531 ciValueKlass* field_klass = field_type->as_value_klass();
532 if (field_klass->is_scalarizable() || vt->field_is_flattened(i)) {
533 value = ValueTypeNode::make_default(gvn, field_klass);
534 } else {
535 value = default_oop(gvn, field_klass);
536 }
537 } else {
538 value = gvn.zerocon(field_type->basic_type());
539 }
540 vt->set_field_value(i, value);
541 }
542 vt = gvn.transform(vt)->as_ValueType();
543 assert(vt->is_default(gvn), "must be the default value type");
544 return vt;
545 }
546
547 bool ValueTypeNode::is_default(PhaseGVN& gvn) const {
548 for (uint i = 0; i < field_count(); ++i) {
549 Node* value = field_value(i);
550 if (!gvn.type(value)->is_zero_type() &&
551 !(value->is_ValueType() && value->as_ValueType()->is_default(gvn)) &&
552 !(field_type(i)->is_valuetype() && value == default_oop(gvn, field_type(i)->as_value_klass()))) {
553 return false;
554 }
555 }
556 return true;
557 }
558
559 ValueTypeNode* ValueTypeNode::make_from_oop(GraphKit* kit, Node* oop, ciValueKlass* vk) {
560 PhaseGVN& gvn = kit->gvn();
561
562 // Create and initialize a ValueTypeNode by loading all field
563 // values from a heap-allocated version and also save the oop.
564 ValueTypeNode* vt = new ValueTypeNode(vk, oop);
565
566 if (oop->isa_ValueTypePtr()) {
567 // Can happen with late inlining
568 ValueTypePtrNode* vtptr = oop->as_ValueTypePtr();
569 vt->set_oop(vtptr->get_oop());
570 for (uint i = Oop+1; i < vtptr->req(); ++i) {
571 vt->init_req(i, vtptr->in(i));
572 }
573 } else if (gvn.type(oop)->maybe_null()) {
574 // Add a null check because the oop may be null
575 Node* null_ctl = kit->top();
576 Node* not_null_oop = kit->null_check_oop(oop, &null_ctl);
577 if (kit->stopped()) {
578 // Constant null
579 kit->set_control(null_ctl);
580 return make_default(gvn, vk);
581 }
582 vt->set_oop(not_null_oop);
583 vt->load(kit, not_null_oop, not_null_oop, vk, /* holder_offset */ 0);
584
585 if (null_ctl != kit->top()) {
586 // Return default value type if oop is null
587 ValueTypeNode* def = make_default(gvn, vk);
588 Node* region = new RegionNode(3);
589 region->init_req(1, kit->control());
590 region->init_req(2, null_ctl);
591
592 vt = vt->clone_with_phis(&gvn, region)->as_ValueType();
593 vt->merge_with(&gvn, def, 2, true);
594 kit->set_control(gvn.transform(region));
595 }
596 } else {
597 // Oop can never be null
598 Node* init_ctl = kit->control();
599 vt->load(kit, oop, oop, vk, /* holder_offset */ 0);
600 assert(init_ctl != kit->control() || oop->is_Con() || oop->is_CheckCastPP() || oop->Opcode() == Op_ValueTypePtr ||
601 vt->is_loaded(&gvn) == oop, "value type should be loaded");
602 }
603
604 assert(vt->is_allocated(&gvn), "value type should be allocated");
605 return gvn.transform(vt)->as_ValueType();
606 }
607
608 // GraphKit wrapper for the 'make_from_flattened' method
609 ValueTypeNode* ValueTypeNode::make_from_flattened(GraphKit* kit, ciValueKlass* vk, Node* obj, Node* ptr, ciInstanceKlass* holder, int holder_offset) {
610 // Create and initialize a ValueTypeNode by loading all field values from
611 // a flattened value type field at 'holder_offset' or from a value type array.
612 ValueTypeNode* vt = make_uninitialized(kit->gvn(), vk);
613 // The value type is flattened into the object without an oop header. Subtract the
614 // offset of the first field to account for the missing header when loading the values.
615 holder_offset -= vk->first_field_offset();
616 vt->load(kit, obj, ptr, holder, holder_offset);
617 assert(vt->is_loaded(&kit->gvn()) != obj, "holder oop should not be used as flattened value type oop");
618 return kit->gvn().transform(vt)->as_ValueType();
619 }
620
621 ValueTypeNode* ValueTypeNode::make_from_multi(GraphKit* kit, MultiNode* multi, ciValueKlass* vk, uint& base_input, bool in) {
622 ValueTypeNode* vt = ValueTypeNode::make_uninitialized(kit->gvn(), vk);
623 vt->initialize(kit, multi, vk, 0, base_input, in);
624 return kit->gvn().transform(vt)->as_ValueType();
625 }
626
627 Node* ValueTypeNode::is_loaded(PhaseGVN* phase, ciValueKlass* vk, Node* base, int holder_offset) {
628 if (vk == NULL) {
629 vk = value_klass();
630 }
631 if (field_count() == 0) {
632 assert(is_allocated(phase), "must be allocated");
633 return get_oop();
634 }
635 for (uint i = 0; i < field_count(); ++i) {
636 int offset = holder_offset + field_offset(i);
637 Node* value = field_value(i);
638 if (value->is_ValueType()) {
639 ValueTypeNode* vt = value->as_ValueType();
640 if (field_is_flattened(i)) {
641 // Check value type field load recursively
642 base = vt->is_loaded(phase, vk, base, offset - vt->value_klass()->first_field_offset());
643 if (base == NULL) {
644 return NULL;
645 }
646 continue;
647 } else {
648 value = vt->get_oop();
649 if (value->Opcode() == Op_CastPP) {
650 // Skip CastPP
651 value = value->in(1);
652 }
653 }
654 }
655 if (value->isa_DecodeN()) {
656 // Skip DecodeN
657 value = value->in(1);
658 }
659 if (value->isa_Load()) {
660 // Check if base and offset of field load matches value type layout
661 intptr_t loffset = 0;
662 Node* lbase = AddPNode::Ideal_base_and_offset(value->in(MemNode::Address), phase, loffset);
663 if (lbase == NULL || (lbase != base && base != NULL) || loffset != offset) {
664 return NULL;
665 } else if (base == NULL) {
666 // Set base and check if pointer type matches
667 base = lbase;
668 const TypeInstPtr* vtptr = phase->type(base)->isa_instptr();
669 if (vtptr == NULL || !vtptr->klass()->equals(vk)) {
670 return NULL;
671 }
672 }
673 } else {
674 return NULL;
675 }
676 }
677 return base;
678 }
679
680 Node* ValueTypeNode::allocate_fields(GraphKit* kit) {
681 ValueTypeNode* vt = clone()->as_ValueType();
682 for (uint i = 0; i < field_count(); i++) {
683 ValueTypeNode* value = field_value(i)->isa_ValueType();
684 if (field_is_flattened(i)) {
685 // Flattened value type field
686 vt->set_field_value(i, value->allocate_fields(kit));
687 } else if (value != NULL){
688 // Non-flattened value type field
689 vt->set_field_value(i, value->allocate(kit));
690 }
691 }
692 vt = kit->gvn().transform(vt)->as_ValueType();
693 kit->replace_in_map(this, vt);
694 return vt;
695 }
696
697 Node* ValueTypeNode::tagged_klass(PhaseGVN& gvn) {
698 ciValueKlass* vk = value_klass();
699 const TypeKlassPtr* tk = TypeKlassPtr::make(vk);
700 intptr_t bits = tk->get_con();
701 set_nth_bit(bits, 0);
702 return gvn.makecon(TypeRawPtr::make((address)bits));
703 }
704
705 uint ValueTypeNode::pass_fields(Node* n, int base_input, GraphKit& kit, bool assert_allocated, ciValueKlass* base_vk, int base_offset) {
706 assert(base_input >= TypeFunc::Parms, "invalid base input");
707 ciValueKlass* vk = value_klass();
708 if (base_vk == NULL) {
709 base_vk = vk;
710 }
711 uint edges = 0;
712 for (uint i = 0; i < field_count(); i++) {
713 int offset = base_offset + field_offset(i) - (base_offset > 0 ? vk->first_field_offset() : 0);
714 Node* arg = field_value(i);
715 if (field_is_flattened(i)) {
716 // Flattened value type field
717 edges += arg->as_ValueType()->pass_fields(n, base_input, kit, assert_allocated, base_vk, offset);
718 } else {
719 int j = 0; int extra = 0;
720 for (; j < base_vk->nof_nonstatic_fields(); j++) {
721 ciField* field = base_vk->nonstatic_field_at(j);
722 if (offset == field->offset()) {
723 assert(field->type() == field_type(i), "inconsistent field type");
724 break;
725 }
726 BasicType bt = field->type()->basic_type();
727 if (bt == T_LONG || bt == T_DOUBLE) {
728 extra++;
729 }
730 }
731 if (arg->is_ValueType()) {
732 // non-flattened value type field
733 ValueTypeNode* vt = arg->as_ValueType();
734 assert(!assert_allocated || vt->is_allocated(&kit.gvn()), "value type field should be allocated");
735 arg = vt->allocate(&kit)->get_oop();
736 }
737
738 int index = base_input + j + extra;
739 n->init_req(index++, arg);
740 edges++;
741 BasicType bt = field_type(i)->basic_type();
742 if (bt == T_LONG || bt == T_DOUBLE) {
743 n->init_req(index++, kit.top());
744 edges++;
745 }
746 if (n->isa_CallJava()) {
747 Method* m = n->as_CallJava()->method()->get_Method();
748 SigEntry res_entry = m->get_res_entry();
749 if ((index - TypeFunc::Parms) == res_entry._offset) {
750 // Skip reserved entry
751 int size = type2size[res_entry._bt];
752 n->init_req(index++, kit.top());
753 if (size == 2) {
754 n->init_req(index++, kit.top());
755 }
756 base_input += size;
757 edges += size;
758 }
759 }
760 }
761 }
762 return edges;
763 }
764
765 Node* ValueTypeNode::Ideal(PhaseGVN* phase, bool can_reshape) {
766 Node* oop = get_oop();
767 if (is_default(*phase) && (!oop->is_Con() || phase->type(oop)->is_zero_type())) {
768 // Use the pre-allocated oop for default value types
769 set_oop(default_oop(*phase, value_klass()));
770 return this;
771 } else if (oop->isa_ValueTypePtr()) {
772 // Can happen with late inlining
773 ValueTypePtrNode* vtptr = oop->as_ValueTypePtr();
774 set_oop(vtptr->get_oop());
775 for (uint i = Oop+1; i < vtptr->req(); ++i) {
776 set_req(i, vtptr->in(i));
777 }
778 return this;
779 }
780
781 if (!is_allocated(phase)) {
782 // Save base oop if fields are loaded from memory and the value
783 // type is not buffered (in this case we should not use the oop).
784 Node* base = is_loaded(phase);
785 if (base != NULL) {
786 set_oop(base);
787 assert(is_allocated(phase), "should now be allocated");
788 return this;
789 }
790 }
791
792 if (can_reshape) {
793 PhaseIterGVN* igvn = phase->is_IterGVN();
794
795 if (is_default(*phase)) {
796 // Search for users of the default value type
797 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
798 Node* user = fast_out(i);
799 AllocateNode* alloc = user->isa_Allocate();
800 if (alloc != NULL && alloc->result_cast() != NULL && alloc->in(AllocateNode::ValueNode) == this) {
801 // Found an allocation of the default value type.
802 // If the code in StoreNode::Identity() that removes useless stores was not yet
803 // executed or ReduceFieldZeroing is disabled, there can still be initializing
804 // stores (only zero-type or default value stores, because value types are immutable).
805 Node* res = alloc->result_cast();
806 for (DUIterator_Fast jmax, j = res->fast_outs(jmax); j < jmax; j++) {
807 AddPNode* addp = res->fast_out(j)->isa_AddP();
808 if (addp != NULL) {
809 for (DUIterator_Fast kmax, k = addp->fast_outs(kmax); k < kmax; k++) {
810 StoreNode* store = addp->fast_out(k)->isa_Store();
811 if (store != NULL && store->outcnt() != 0) {
812 // Remove the useless store
813 Node* mem = store->in(MemNode::Memory);
814 Node* val = store->in(MemNode::ValueIn);
815 val = val->is_EncodeP() ? val->in(1) : val;
816 const Type* val_type = igvn->type(val);
817 assert(val_type->is_zero_type() || (val->is_Con() && val_type->make_ptr()->is_valuetypeptr()),
818 "must be zero-type or default value store");
819 igvn->replace_in_uses(store, mem);
820 }
821 }
822 }
823 }
824 // Replace allocation by pre-allocated oop
825 igvn->replace_node(res, default_oop(*phase, value_klass()));
826 } else if (user->is_ValueType()) {
827 // Add value type user to worklist to give it a chance to get optimized as well
828 igvn->_worklist.push(user);
829 }
830 }
831 }
832
833 if (is_allocated(igvn)) {
834 // Value type is heap allocated, search for safepoint uses
835 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
836 Node* out = fast_out(i);
837 if (out->is_SafePoint()) {
838 // Let SafePointNode::Ideal() take care of re-wiring the
839 // safepoint to the oop input instead of the value type node.
840 igvn->rehash_node_delayed(out);
841 }
842 }
843 }
844 }
845 return NULL;
846 }
847
848 // Search for multiple allocations of this value type
849 // and try to replace them by dominating allocations.
850 void ValueTypeNode::remove_redundant_allocations(PhaseIterGVN* igvn, PhaseIdealLoop* phase) {
851 assert(EliminateAllocations, "allocation elimination should be enabled");
852 // Search for allocations of this value type
853 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
854 AllocateNode* alloc = fast_out(i)->isa_Allocate();
855 if (alloc != NULL && alloc->result_cast() != NULL && alloc->in(AllocateNode::ValueNode) == this) {
856 assert(!is_default(*igvn), "default value type allocation");
857 Node* res_dom = NULL;
858 if (is_allocated(igvn)) {
859 // The value type is already allocated but still connected to an AllocateNode.
860 // This can happen with late inlining when we first allocate a value type argument
861 // but later decide to inline the call with the callee code also allocating.
862 res_dom = get_oop();
863 } else {
864 // Search for a dominating allocation of the same value type
865 for (DUIterator_Fast jmax, j = fast_outs(jmax); j < jmax; j++) {
866 Node* out2 = fast_out(j);
867 if (alloc != out2 && out2->is_Allocate() && out2->in(AllocateNode::ValueNode) == this &&
868 phase->is_dominator(out2, alloc)) {
869 AllocateNode* alloc_dom = out2->as_Allocate();
870 assert(alloc->in(AllocateNode::KlassNode) == alloc_dom->in(AllocateNode::KlassNode), "klasses should match");
871 res_dom = alloc_dom->result_cast();
872 break;
873 }
874 }
875 }
876 if (res_dom != NULL) {
877 // Move users to dominating allocation
878 Node* res = alloc->result_cast();
879 igvn->replace_node(res, res_dom);
880 // The result of the dominated allocation is now unused and will be
881 // removed later in AllocateNode::Ideal() to not confuse loop opts.
882 igvn->record_for_igvn(alloc);
883 #ifdef ASSERT
884 if (PrintEliminateAllocations) {
885 tty->print("++++ Eliminated: %d Allocate ", alloc->_idx);
886 dump_spec(tty);
887 tty->cr();
888 }
889 #endif
890 }
891 }
892 }
893
894 // Process users
895 for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
896 Node* out = fast_out(i);
897 if (out->is_ValueType()) {
898 // Recursively process value type users
899 out->as_ValueType()->remove_redundant_allocations(igvn, phase);
900 } else if (out->isa_Allocate() != NULL) {
901 // Allocate users should be linked
902 assert(out->in(AllocateNode::ValueNode) == this, "should be linked");
903 } else {
904 #ifdef ASSERT
905 // The value type should not have any other users at this time
906 out->dump();
907 assert(false, "unexpected user of value type");
908 #endif
909 }
910 }
911 }
912
913 ValueTypePtrNode* ValueTypePtrNode::make_from_value_type(GraphKit* kit, ValueTypeNode* vt, bool deoptimize_on_exception) {
914 Node* oop = vt->allocate(kit, deoptimize_on_exception)->get_oop();
915 ValueTypePtrNode* vtptr = new ValueTypePtrNode(vt->value_klass(), oop);
916 for (uint i = Oop+1; i < vt->req(); i++) {
917 vtptr->init_req(i, vt->in(i));
918 }
919 return kit->gvn().transform(vtptr)->as_ValueTypePtr();
920 }
921
922 ValueTypePtrNode* ValueTypePtrNode::make_from_oop(GraphKit* kit, Node* oop) {
923 // Create and initialize a ValueTypePtrNode by loading all field
924 // values from a heap-allocated version and also save the oop.
925 ciValueKlass* vk = kit->gvn().type(oop)->value_klass();
926 ValueTypePtrNode* vtptr = new ValueTypePtrNode(vk, oop);
927 vtptr->load(kit, oop, oop, vk);
928 return kit->gvn().transform(vtptr)->as_ValueTypePtr();
929 }