1 /*
  2  * Copyright (c) 2016, 2026, 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 "ci/ciFlatArrayKlass.hpp"
 26 #include "gc/shared/barrierSet.hpp"
 27 #include "gc/shared/c2/barrierSetC2.hpp"
 28 #include "gc/shared/c2/cardTableBarrierSetC2.hpp"
 29 #include "gc/shared/gc_globals.hpp"
 30 #include "opto/arraycopynode.hpp"
 31 #include "opto/graphKit.hpp"
 32 #include "opto/inlinetypenode.hpp"
 33 #include "utilities/powerOfTwo.hpp"
 34 
 35 const TypeFunc* ArrayCopyNode::_arraycopy_type_Type = nullptr;
 36 
 37 ArrayCopyNode::ArrayCopyNode(Compile* C, bool alloc_tightly_coupled, bool has_negative_length_guard)
 38   : CallNode(arraycopy_type(), nullptr, TypePtr::BOTTOM),
 39     _kind(None),
 40     _alloc_tightly_coupled(alloc_tightly_coupled),
 41     _has_negative_length_guard(has_negative_length_guard),
 42     _arguments_validated(false),
 43     _src_type(TypeOopPtr::BOTTOM),
 44     _dest_type(TypeOopPtr::BOTTOM) {
 45   init_class_id(Class_ArrayCopy);
 46   init_flags(Flag_is_macro);
 47   C->add_macro_node(this);
 48 }
 49 
 50 uint ArrayCopyNode::size_of() const { return sizeof(*this); }
 51 
 52 ArrayCopyNode* ArrayCopyNode::make(GraphKit* kit, bool may_throw,
 53                                    Node* src, Node* src_offset,
 54                                    Node* dest, Node* dest_offset,
 55                                    Node* length,
 56                                    bool alloc_tightly_coupled,
 57                                    bool has_negative_length_guard,
 58                                    Node* src_klass, Node* dest_klass,
 59                                    Node* src_length, Node* dest_length) {
 60 
 61   ArrayCopyNode* ac = new ArrayCopyNode(kit->C, alloc_tightly_coupled, has_negative_length_guard);
 62   kit->set_predefined_input_for_runtime_call(ac);
 63 
 64   ac->init_req(ArrayCopyNode::Src, src);
 65   ac->init_req(ArrayCopyNode::SrcPos, src_offset);
 66   ac->init_req(ArrayCopyNode::Dest, dest);
 67   ac->init_req(ArrayCopyNode::DestPos, dest_offset);
 68   ac->init_req(ArrayCopyNode::Length, length);
 69   ac->init_req(ArrayCopyNode::SrcLen, src_length);
 70   ac->init_req(ArrayCopyNode::DestLen, dest_length);
 71   ac->init_req(ArrayCopyNode::SrcKlass, src_klass);
 72   ac->init_req(ArrayCopyNode::DestKlass, dest_klass);
 73 
 74   if (may_throw) {
 75     ac->set_req(TypeFunc::I_O , kit->i_o());
 76     kit->add_safepoint_edges(ac, false);
 77   }
 78 
 79   return ac;
 80 }
 81 
 82 void ArrayCopyNode::connect_outputs(GraphKit* kit, bool deoptimize_on_exception) {
 83   kit->set_all_memory_call(this, true);
 84   kit->set_control(kit->gvn().transform(new ProjNode(this,TypeFunc::Control)));
 85   kit->set_i_o(kit->gvn().transform(new ProjNode(this, TypeFunc::I_O)));
 86   kit->make_slow_call_ex(this, kit->env()->Throwable_klass(), true, deoptimize_on_exception);
 87   kit->set_all_memory_call(this);
 88 }
 89 
 90 #ifndef PRODUCT
 91 const char* ArrayCopyNode::_kind_names[] = {"arraycopy", "arraycopy, validated arguments", "clone", "oop array clone", "CopyOf", "CopyOfRange"};
 92 
 93 void ArrayCopyNode::dump_spec(outputStream *st) const {
 94   CallNode::dump_spec(st);
 95   st->print(" (%s%s)", _kind_names[_kind], _alloc_tightly_coupled ? ", tightly coupled allocation" : "");
 96 }
 97 
 98 void ArrayCopyNode::dump_compact_spec(outputStream* st) const {
 99   st->print("%s%s", _kind_names[_kind], _alloc_tightly_coupled ? ",tight" : "");
100 }
101 #endif
102 
103 intptr_t ArrayCopyNode::get_length_if_constant(PhaseGVN *phase) const {
104   // check that length is constant
105   Node* length = in(ArrayCopyNode::Length);
106   const Type* length_type = phase->type(length);
107 
108   if (length_type == Type::TOP) {
109     return -1;
110   }
111 
112   assert(is_clonebasic() || is_arraycopy() || is_copyof() || is_copyofrange(), "unexpected array copy type");
113 
114   return is_clonebasic() ? length->find_intptr_t_con(-1) : length->find_int_con(-1);
115 }
116 
117 int ArrayCopyNode::get_count(PhaseGVN *phase) const {
118   if (is_clonebasic()) {
119     Node* src = in(ArrayCopyNode::Src);
120     const Type* src_type = phase->type(src);
121 
122     if (src_type == Type::TOP) {
123       return -1;
124     }
125 
126     if (src_type->isa_instptr()) {
127       const TypeInstPtr* inst_src = src_type->is_instptr();
128       ciInstanceKlass* ik = inst_src->instance_klass();
129       // ciInstanceKlass::nof_nonstatic_fields() doesn't take injected
130       // fields into account. They are rare anyway so easier to simply
131       // skip instances with injected fields.
132       if ((!inst_src->klass_is_exact() && (ik->is_interface() || ik->has_subklass())) || ik->has_injected_fields()) {
133         return -1;
134       }
135       int nb_fields = ik->nof_nonstatic_fields();
136       return nb_fields;
137     } else {
138       const TypeAryPtr* ary_src = src_type->isa_aryptr();
139       assert (ary_src != nullptr, "not an array or instance?");
140       // clone passes a length as a rounded number of longs. If we're
141       // cloning an array we'll do it element by element. If the
142       // length of the input array is constant, ArrayCopyNode::Length
143       // must be too. Note that the opposite does not need to hold,
144       // because different input array lengths (e.g. int arrays with
145       // 3 or 4 elements) might lead to the same length input
146       // (e.g. 2 double-words).
147       assert(!ary_src->size()->is_con() || (get_length_if_constant(phase) >= 0) ||
148              (UseArrayFlattening && ary_src->elem()->make_oopptr() != nullptr && ary_src->elem()->make_oopptr()->can_be_inline_type()) ||
149              phase->is_IterGVN() || phase->C->inlining_incrementally() || StressReflectiveCode, "inconsistent");
150       if (ary_src->size()->is_con()) {
151         return ary_src->size()->get_con();
152       }
153       return -1;
154     }
155   }
156 
157   return get_length_if_constant(phase);
158 }
159 
160 Node* ArrayCopyNode::load(BarrierSetC2* bs, PhaseGVN *phase, Node*& ctl, MergeMemNode* mem, Node* adr, const TypePtr* adr_type, const Type *type, BasicType bt) {
161   // Pin the load: if this is an array load, it's going to be dependent on a condition that's not a range check for that
162   // access. If that condition is replaced by an identical dominating one, then an unpinned load would risk floating
163   // above runtime checks that guarantee it is within bounds.
164   DecoratorSet decorators = C2_READ_ACCESS | C2_CONTROL_DEPENDENT_LOAD | IN_HEAP | C2_ARRAY_COPY | C2_UNKNOWN_CONTROL_LOAD;
165   C2AccessValuePtr addr(adr, adr_type);
166   C2OptAccess access(*phase, ctl, mem, decorators, bt, adr->in(AddPNode::Base), addr);
167   Node* res = bs->load_at(access, type);
168   ctl = access.ctl();
169   return res;
170 }
171 
172 void ArrayCopyNode::store(BarrierSetC2* bs, PhaseGVN *phase, Node*& ctl, MergeMemNode* mem, Node* adr, const TypePtr* adr_type, Node* val, const Type *type, BasicType bt) {
173   DecoratorSet decorators = C2_WRITE_ACCESS | IN_HEAP | C2_ARRAY_COPY;
174   if (is_alloc_tightly_coupled()) {
175     decorators |= C2_TIGHTLY_COUPLED_ALLOC;
176   }
177   C2AccessValuePtr addr(adr, adr_type);
178   C2AccessValue value(val, type);
179   C2OptAccess access(*phase, ctl, mem, decorators, bt, adr->in(AddPNode::Base), addr);
180   bs->store_at(access, value);
181   ctl = access.ctl();
182 }
183 
184 
185 Node* ArrayCopyNode::try_clone_instance(PhaseGVN *phase, bool can_reshape, int count) {
186   if (!is_clonebasic()) {
187     return nullptr;
188   }
189 
190   Node* out_mem = proj_out_or_null(TypeFunc::Memory);
191   if (can_reshape && out_mem == nullptr) { // dead node?
192     return NodeSentinel;
193   }
194 
195 
196   Node* base_src = in(ArrayCopyNode::Src);
197   Node* base_dest = in(ArrayCopyNode::Dest);
198   Node* ctl = in(TypeFunc::Control);
199   Node* in_mem = in(TypeFunc::Memory);
200 
201   const Type* src_type = phase->type(base_src);
202   const TypeInstPtr* inst_src = src_type->isa_instptr();
203   if (inst_src == nullptr) {
204     return nullptr;
205   }
206 
207   MergeMemNode* mem = phase->transform(MergeMemNode::make(in_mem))->as_MergeMem();
208   phase->record_for_igvn(mem);
209   if (can_reshape) {
210     phase->is_IterGVN()->_worklist.push(mem);
211   }
212 
213 
214   ciInstanceKlass* ik = inst_src->instance_klass();
215 
216   if (!inst_src->klass_is_exact()) {
217     assert(!ik->is_interface(), "inconsistent klass hierarchy");
218     if (ik->has_subklass()) {
219       // Concurrent class loading.
220       // Fail fast and return NodeSentinel to indicate that the transform failed.
221       return NodeSentinel;
222     } else {
223       phase->C->dependencies()->assert_leaf_type(ik);
224     }
225   }
226 
227   const TypeInstPtr* dest_type = phase->type(base_dest)->is_instptr();
228   if (dest_type->instance_klass() != ik) {
229     // At parse time, the exact type of the object to clone was not known. That inexact type was captured by the CheckCastPP
230     // of the newly allocated cloned object (in dest). The exact type is now known (in src), but the type for the cloned object
231     // (dest) was not updated. When copying the fields below, Store nodes may write to offsets for fields that don't exist in
232     // the inexact class. The stores would then be assigned an incorrect slice.
233     return NodeSentinel;
234   }
235 
236   assert(ik->nof_nonstatic_fields() <= ArrayCopyLoadStoreMaxElem, "too many fields");
237 
238   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
239   for (int i = 0; i < count; i++) {
240     ciField* field = ik->nonstatic_field_at(i);
241     const TypePtr* adr_type = phase->C->alias_type(field)->adr_type();
242     Node* off = phase->MakeConX(field->offset_in_bytes());
243     Node* next_src = phase->transform(AddPNode::make_with_base(base_src, off));
244     Node* next_dest = phase->transform(AddPNode::make_with_base(base_dest, off));
245     assert(phase->C->get_alias_index(adr_type) == phase->C->get_alias_index(phase->type(next_src)->isa_ptr()),
246       "slice of address and input slice don't match");
247     assert(phase->C->get_alias_index(adr_type) == phase->C->get_alias_index(phase->type(next_dest)->isa_ptr()),
248       "slice of address and input slice don't match");
249     BasicType bt = field->layout_type();
250 
251     const Type *type;
252     if (bt == T_OBJECT) {
253       if (!field->type()->is_loaded()) {
254         type = TypeInstPtr::BOTTOM;
255       } else {
256         ciType* field_klass = field->type();
257         type = TypeOopPtr::make_from_klass(field_klass->as_klass());
258       }
259     } else {
260       type = Type::get_const_basic_type(bt);
261     }
262 
263     Node* v = load(bs, phase, ctl, mem, next_src, adr_type, type, bt);
264     store(bs, phase, ctl, mem, next_dest, adr_type, v, type, bt);
265   }
266 
267   if (!finish_transform(phase, can_reshape, ctl, mem)) {
268     // Return NodeSentinel to indicate that the transform failed
269     return NodeSentinel;
270   }
271 
272   return mem;
273 }
274 
275 // We may have narrowed the type of base because this runs with PhaseIterGVN::_delay_transform true, explicitly
276 // update the type of the AddP so it's consistent with its base and load() picks the right memory slice.
277 Node* ArrayCopyNode::make_and_transform_addp(PhaseGVN* phase, Node* base, Node* offset) {
278   return make_and_transform_addp(phase, base, base, offset);
279 }
280 
281 Node* ArrayCopyNode::make_and_transform_addp(PhaseGVN* phase, Node* base, Node* ptr, Node* offset) {
282   assert(phase->is_IterGVN() == nullptr || phase->is_IterGVN()->delay_transform(), "helper method when delay transform is set");
283   Node* addp = phase->transform(AddPNode::make_with_base(base, ptr, offset));
284   phase->set_type(addp, addp->Value(phase));
285   return addp;
286 }
287 
288 bool ArrayCopyNode::prepare_array_copy(PhaseGVN *phase, bool can_reshape,
289                                        Node*& adr_src,
290                                        Node*& base_src,
291                                        Node*& adr_dest,
292                                        Node*& base_dest,
293                                        BasicType& copy_type,
294                                        const Type*& value_type,
295                                        bool& disjoint_bases) {
296   base_src = in(ArrayCopyNode::Src);
297   base_dest = in(ArrayCopyNode::Dest);
298   const Type* src_type = phase->type(base_src);
299   const TypeAryPtr* ary_src = src_type->isa_aryptr();
300 
301   Node* src_offset = in(ArrayCopyNode::SrcPos);
302   Node* dest_offset = in(ArrayCopyNode::DestPos);
303 
304   if (is_arraycopy() || is_copyofrange() || is_copyof()) {
305     const Type* dest_type = phase->type(base_dest);
306     const TypeAryPtr* ary_dest = dest_type->isa_aryptr();
307 
308     // newly allocated object is guaranteed to not overlap with source object
309     disjoint_bases = is_alloc_tightly_coupled();
310     if (ary_src  == nullptr || ary_src->elem()  == Type::BOTTOM ||
311         ary_dest == nullptr || ary_dest->elem() == Type::BOTTOM) {
312       // We don't know if arguments are arrays
313       return false;
314     }
315 
316     BasicType src_elem = ary_src->elem()->array_element_basic_type();
317     BasicType dest_elem = ary_dest->elem()->array_element_basic_type();
318     if (is_reference_type(src_elem, true)) src_elem = T_OBJECT;
319     if (is_reference_type(dest_elem, true)) dest_elem = T_OBJECT;
320 
321     // TODO 8251971 What about atomicity?
322     if (src_elem != dest_elem || ary_src->is_null_free() != ary_dest->is_null_free() || ary_src->is_flat() != ary_dest->is_flat() || dest_elem == T_VOID) {
323       // We don't know if arguments are arrays of the same type
324       return false;
325     }
326 
327     BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
328     if ((!ary_dest->is_flat() && bs->array_copy_requires_gc_barriers(is_alloc_tightly_coupled(), dest_elem, false, false, BarrierSetC2::Optimization)) ||
329         (ary_dest->is_flat() && ary_src->elem()->inline_klass()->contains_oops() &&
330          bs->array_copy_requires_gc_barriers(is_alloc_tightly_coupled(), T_OBJECT, false, false, BarrierSetC2::Optimization))) {
331       // It's an object array copy but we can't emit the card marking that is needed
332       return false;
333     }
334 
335     value_type = ary_src->elem();
336 
337     uint shift  = exact_log2(type2aelembytes(dest_elem));
338     if (ary_dest->is_flat()) {
339       assert(ary_src->is_flat(), "src and dest must be flat");
340       shift = ary_src->flat_log_elem_size();
341       src_elem = T_FLAT_ELEMENT;
342       dest_elem = T_FLAT_ELEMENT;
343     }
344 
345     const uint header = arrayOopDesc::base_offset_in_bytes(dest_elem);
346 
347     src_offset = Compile::conv_I2X_index(phase, src_offset, ary_src->size());
348     if (src_offset->is_top()) {
349       // Offset is out of bounds (the ArrayCopyNode will be removed)
350       return false;
351     }
352     dest_offset = Compile::conv_I2X_index(phase, dest_offset, ary_dest->size());
353     if (dest_offset->is_top()) {
354       // Offset is out of bounds (the ArrayCopyNode will be removed)
355       if (can_reshape) {
356         // record src_offset, so it can be deleted later (if it is dead)
357         phase->is_IterGVN()->_worklist.push(src_offset);
358       }
359       return false;
360     }
361 
362     Node* hook = new Node(1);
363     hook->init_req(0, dest_offset);
364 
365     Node* src_scale  = phase->transform(new LShiftXNode(src_offset, phase->intcon(shift)));
366 
367     hook->destruct(phase);
368 
369     Node* dest_scale = phase->transform(new LShiftXNode(dest_offset, phase->intcon(shift)));
370 
371     adr_src = make_and_transform_addp(phase, base_src, src_scale);
372     adr_dest = make_and_transform_addp(phase, base_dest, dest_scale);
373 
374     adr_src = make_and_transform_addp(phase, base_src, adr_src, phase->MakeConX(header));
375     adr_dest = make_and_transform_addp(phase, base_dest, adr_dest, phase->MakeConX(header));
376     copy_type = dest_elem;
377   } else {
378     assert(ary_src != nullptr, "should be a clone");
379     assert(is_clonebasic(), "should be");
380 
381     disjoint_bases = true;
382 
383     if (ary_src->elem()->make_oopptr() != nullptr &&
384         ary_src->elem()->make_oopptr()->can_be_inline_type()) {
385       return false;
386     }
387 
388     BasicType elem = ary_src->isa_aryptr()->elem()->array_element_basic_type();
389     if (is_reference_type(elem, true)) {
390       elem = T_OBJECT;
391     }
392 
393     BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
394     if ((!ary_src->is_flat() && bs->array_copy_requires_gc_barriers(true, elem, true, is_clone_inst(), BarrierSetC2::Optimization)) ||
395         (ary_src->is_flat() && ary_src->elem()->inline_klass()->contains_oops() &&
396          bs->array_copy_requires_gc_barriers(true, T_OBJECT, true, is_clone_inst(), BarrierSetC2::Optimization))) {
397       // It's an object array copy but we can't emit the card marking that is needed
398       return false;
399     }
400 
401     adr_src = make_and_transform_addp(phase, base_src, src_offset);
402     adr_dest = make_and_transform_addp(phase, base_dest, dest_offset);
403 
404     // The address is offsetted to an aligned address where a raw copy would start.
405     // If the clone copy is decomposed into load-stores - the address is adjusted to
406     // point at where the array starts.
407     const Type* toff = phase->type(src_offset);
408     int offset = toff->isa_long() ? (int) toff->is_long()->get_con() : (int) toff->is_int()->get_con();
409     int diff = arrayOopDesc::base_offset_in_bytes(elem) - offset;
410     assert(diff >= 0, "clone should not start after 1st array element");
411     if (diff > 0) {
412       adr_src = make_and_transform_addp(phase, base_src, adr_src, phase->MakeConX(diff));
413       adr_dest = make_and_transform_addp(phase, base_dest, adr_dest, phase->MakeConX(diff));
414     }
415     copy_type = elem;
416     value_type = ary_src->elem();
417   }
418   return true;
419 }
420 
421 const TypeAryPtr* ArrayCopyNode::get_address_type(PhaseGVN* phase, const TypePtr* atp, Node* n) {
422   if (atp == TypeOopPtr::BOTTOM) {
423     atp = phase->type(n)->isa_ptr();
424   }
425   // adjust atp to be the correct array element address type
426   return atp->add_offset(Type::OffsetBot)->is_aryptr();
427 }
428 
429 const TypePtr* ArrayCopyNode::get_src_adr_type(PhaseGVN* phase) const {
430   return get_address_type(phase, _src_type, in(Src));
431 }
432 
433 void ArrayCopyNode::array_copy_test_overlap(GraphKit& kit, bool disjoint_bases, int count, Node*& backward_ctl) {
434   Node* ctl = kit.control();
435   if (!disjoint_bases && count > 1) {
436     PhaseGVN& gvn = kit.gvn();
437     Node* src_offset = in(ArrayCopyNode::SrcPos);
438     Node* dest_offset = in(ArrayCopyNode::DestPos);
439     assert(src_offset != nullptr && dest_offset != nullptr, "should be");
440     Node* cmp = gvn.transform(new CmpINode(src_offset, dest_offset));
441     Node *bol = gvn.transform(new BoolNode(cmp, BoolTest::lt));
442     IfNode *iff = new IfNode(ctl, bol, PROB_FAIR, COUNT_UNKNOWN);
443 
444     gvn.transform(iff);
445 
446     kit.set_control(gvn.transform(new IfFalseNode(iff)));
447     backward_ctl = gvn.transform(new IfTrueNode(iff));
448   }
449 }
450 
451 void ArrayCopyNode::copy(GraphKit& kit,
452                          const TypeAryPtr* atp_src,
453                          const TypeAryPtr* atp_dest,
454                          int i,
455                          Node* base_src,
456                          Node* base_dest,
457                          Node* adr_src,
458                          Node* adr_dest,
459                          BasicType copy_type,
460                          const Type* value_type) {
461   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
462   Node* ctl = kit.control();
463   if (atp_dest->is_flat()) {
464     ciInlineKlass* vk = atp_src->elem()->inline_klass();
465     for (int j = 0; j < vk->nof_nonstatic_fields(); j++) {
466       ciField* field = vk->nonstatic_field_at(j);
467       int off_in_vt = field->offset_in_bytes() - vk->payload_offset();
468       Node* off  = kit.MakeConX(off_in_vt + i * atp_src->flat_elem_size());
469       ciType* ft = field->type();
470       BasicType bt = type2field[ft->basic_type()];
471       assert(!field->is_flat(), "flat field encountered");
472       const Type* rt = Type::get_const_type(ft);
473       const TypePtr* adr_type = atp_src->with_field_offset(off_in_vt)->add_offset(Type::OffsetBot);
474       assert(!bs->array_copy_requires_gc_barriers(is_alloc_tightly_coupled(), bt, false, false, BarrierSetC2::Optimization), "GC barriers required");
475       Node* next_src = make_and_transform_addp(&kit.gvn(), base_src, adr_src, off);
476       Node* next_dest = make_and_transform_addp(&kit.gvn(), base_dest, adr_dest, off);
477       Node* v = load(bs, &kit.gvn(), ctl, kit.merged_memory(), next_src, adr_type, rt, bt);
478       store(bs, &kit.gvn(), ctl, kit.merged_memory(), next_dest, adr_type, v, rt, bt);
479     }
480   } else {
481     Node* off = kit.MakeConX(type2aelembytes(copy_type) * i);
482     Node* next_src = make_and_transform_addp(&kit.gvn(), base_src, adr_src, off);
483     Node* next_dest = make_and_transform_addp(&kit.gvn(), base_dest, adr_dest, off);
484     Node* v = load(bs, &kit.gvn(), ctl, kit.merged_memory(), next_src, atp_src, value_type, copy_type);
485     store(bs, &kit.gvn(), ctl, kit.merged_memory(), next_dest, atp_dest, v, value_type, copy_type);
486   }
487   kit.set_control(ctl);
488 }
489 
490 
491 void ArrayCopyNode::array_copy_forward(GraphKit& kit,
492                                        bool can_reshape,
493                                        const TypeAryPtr* atp_src,
494                                        const TypeAryPtr* atp_dest,
495                                        Node* adr_src,
496                                        Node* base_src,
497                                        Node* adr_dest,
498                                        Node* base_dest,
499                                        BasicType copy_type,
500                                        const Type* value_type,
501                                        int count) {
502   if (!kit.stopped()) {
503     // copy forward
504     if (count > 0) {
505       for (int i = 0; i < count; i++) {
506         copy(kit, atp_src, atp_dest, i, base_src, base_dest, adr_src, adr_dest, copy_type, value_type);
507       }
508     } else if (can_reshape) {
509       PhaseGVN& gvn = kit.gvn();
510       assert(gvn.is_IterGVN(), "");
511       gvn.record_for_igvn(adr_src);
512       gvn.record_for_igvn(adr_dest);
513     }
514   }
515 }
516 
517 void ArrayCopyNode::array_copy_backward(GraphKit& kit,
518                                         bool can_reshape,
519                                         const TypeAryPtr* atp_src,
520                                         const TypeAryPtr* atp_dest,
521                                         Node* adr_src,
522                                         Node* base_src,
523                                         Node* adr_dest,
524                                         Node* base_dest,
525                                         BasicType copy_type,
526                                         const Type* value_type,
527                                         int count) {
528   if (!kit.stopped()) {
529     // copy backward
530 
531     if (count > 0) {
532       for (int i = count-1; i >= 0; i--) {
533         copy(kit, atp_src, atp_dest, i, base_src, base_dest, adr_src, adr_dest, copy_type, value_type);
534       }
535     } else if(can_reshape) {
536       PhaseGVN& gvn = kit.gvn();
537       assert(gvn.is_IterGVN(), "");
538       gvn.record_for_igvn(adr_src);
539       gvn.record_for_igvn(adr_dest);
540     }
541   }
542 }
543 
544 bool ArrayCopyNode::finish_transform(PhaseGVN *phase, bool can_reshape,
545                                      Node* ctl, Node *mem) {
546   if (can_reshape) {
547     PhaseIterGVN* igvn = phase->is_IterGVN();
548     igvn->set_delay_transform(false);
549     if (is_clonebasic()) {
550       Node* out_mem = proj_out(TypeFunc::Memory);
551 
552       BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
553       if (out_mem->outcnt() != 1 || !out_mem->raw_out(0)->is_MergeMem() ||
554           out_mem->raw_out(0)->outcnt() != 1 || !out_mem->raw_out(0)->raw_out(0)->is_MemBar()) {
555         assert(bs->array_copy_requires_gc_barriers(true, T_OBJECT, true, is_clone_inst(), BarrierSetC2::Optimization), "can only happen with card marking");
556         return false;
557       }
558 
559       igvn->replace_node(out_mem->raw_out(0), mem);
560 
561       Node* out_ctl = proj_out(TypeFunc::Control);
562       igvn->replace_node(out_ctl, ctl);
563     } else {
564       // replace fallthrough projections of the ArrayCopyNode by the
565       // new memory, control and the input IO.
566       CallProjections* callprojs = extract_projections(true, false);
567 
568       if (callprojs->fallthrough_ioproj != nullptr) {
569         igvn->replace_node(callprojs->fallthrough_ioproj, in(TypeFunc::I_O));
570       }
571       if (callprojs->fallthrough_memproj != nullptr) {
572         igvn->replace_node(callprojs->fallthrough_memproj, mem);
573       }
574       if (callprojs->fallthrough_catchproj != nullptr) {
575         igvn->replace_node(callprojs->fallthrough_catchproj, ctl);
576       }
577 
578       // The ArrayCopyNode is not disconnected. It still has the
579       // projections for the exception case. Replace current
580       // ArrayCopyNode with a dummy new one with a top() control so
581       // that this part of the graph stays consistent but is
582       // eventually removed.
583 
584       set_req(0, phase->C->top());
585       remove_dead_region(phase, can_reshape);
586     }
587   } else {
588     if (in(TypeFunc::Control) != ctl) {
589       // we can't return new memory and control from Ideal at parse time
590       assert(!is_clonebasic() || UseShenandoahGC, "added control for clone?");
591       phase->record_for_igvn(this);
592       return false;
593     }
594   }
595   return true;
596 }
597 
598 
599 Node *ArrayCopyNode::Ideal(PhaseGVN *phase, bool can_reshape) {
600   // Perform any generic optimizations first
601   Node* result = SafePointNode::Ideal(phase, can_reshape);
602   if (result != nullptr) {
603     return result;
604   }
605 
606   if (StressArrayCopyMacroNode && !can_reshape) {
607     phase->record_for_igvn(this);
608     return nullptr;
609   }
610 
611   // See if it's a small array copy and we can inline it as
612   // loads/stores
613   // Here we can only do:
614   // - arraycopy if all arguments were validated before and we don't
615   // need card marking
616   // - clone for which we don't need to do card marking
617 
618   if (!is_clonebasic() && !is_arraycopy_validated() &&
619       !is_copyofrange_validated() && !is_copyof_validated()) {
620     return nullptr;
621   }
622 
623   assert(in(TypeFunc::Control) != nullptr &&
624          in(TypeFunc::Memory) != nullptr &&
625          in(ArrayCopyNode::Src) != nullptr &&
626          in(ArrayCopyNode::Dest) != nullptr &&
627          in(ArrayCopyNode::Length) != nullptr &&
628          in(ArrayCopyNode::SrcPos) != nullptr &&
629          in(ArrayCopyNode::DestPos) != nullptr, "broken inputs");
630 
631   if (in(TypeFunc::Control)->is_top() ||
632       in(TypeFunc::Memory)->is_top() ||
633       phase->type(in(ArrayCopyNode::Src)) == Type::TOP ||
634       phase->type(in(ArrayCopyNode::Dest)) == Type::TOP ||
635       (in(ArrayCopyNode::SrcPos) != nullptr && in(ArrayCopyNode::SrcPos)->is_top()) ||
636       (in(ArrayCopyNode::DestPos) != nullptr && in(ArrayCopyNode::DestPos)->is_top())) {
637     return nullptr;
638   }
639 
640   int count = get_count(phase);
641 
642   if (count < 0 || count > ArrayCopyLoadStoreMaxElem) {
643     return nullptr;
644   }
645 
646   Node* src = in(ArrayCopyNode::Src);
647   Node* dest = in(ArrayCopyNode::Dest);
648   const Type* src_type = phase->type(src);
649   const Type* dest_type = phase->type(dest);
650 
651   if (src_type->isa_aryptr() && dest_type->isa_instptr()) {
652     // clone used for load of unknown inline type can't be optimized at
653     // this point
654     return nullptr;
655   }
656 
657   Node* mem = try_clone_instance(phase, can_reshape, count);
658   if (mem != nullptr) {
659     return (mem == NodeSentinel) ? nullptr : mem;
660   }
661 
662   Node* adr_src = nullptr;
663   Node* base_src = nullptr;
664   Node* adr_dest = nullptr;
665   Node* base_dest = nullptr;
666   BasicType copy_type = T_ILLEGAL;
667   const Type* value_type = nullptr;
668   bool disjoint_bases = false;
669 
670   // EA may have moved an input to a new slice. EA stores the new address types in the ArrayCopy node itself
671   // (_src_type/_dest_type). phase->type(src) and _src_type or phase->type(dest) and _dest_type may be different
672   // when this transformation runs if igvn hasn't had a chance to propagate the new types yet. Make sure the new
673   // types are taken into account so new Load/Store nodes are created on the right slice.
674   const TypeAryPtr* atp_src = get_address_type(phase, _src_type, src);
675   const TypeAryPtr* atp_dest = get_address_type(phase, _dest_type, dest);
676   phase->set_type(src, phase->type(src)->join_speculative(atp_src));
677   phase->set_type(dest, phase->type(dest)->join_speculative(atp_dest));
678 
679   // Control flow is going to be created, it's easier to do with _delay_transform set to true.
680 
681   // prepare_array_copy() doesn't build control flow, but it creates AddP nodes. The src/dest type possibly gets
682   // narrowed above. If a newly created AddP node is commoned with a pre-existing one, then the type narrowing is lost.
683   // Setting _delay_transform before prepare_array_copy() guarantees this doesn't happen.
684   if (can_reshape) {
685     assert(!phase->is_IterGVN()->delay_transform(), "cannot delay transforms");
686     phase->is_IterGVN()->set_delay_transform(true);
687   }
688 
689   if (!prepare_array_copy(phase, can_reshape,
690                           adr_src, base_src, adr_dest, base_dest,
691                           copy_type, value_type, disjoint_bases)) {
692     assert(adr_src == nullptr, "no node can be left behind");
693     assert(adr_dest == nullptr, "no node can be left behind");
694     if (can_reshape) {
695       assert(phase->is_IterGVN()->delay_transform(), "cannot delay transforms");
696       phase->is_IterGVN()->set_delay_transform(false);
697     }
698 
699     return nullptr;
700   }
701 
702   JVMState* new_jvms = nullptr;
703   SafePointNode* new_map = nullptr;
704   if (!is_clonebasic()) {
705     new_jvms = jvms()->clone_shallow(phase->C);
706     new_map = new SafePointNode(req(), new_jvms);
707     for (uint i = TypeFunc::FramePtr; i < req(); i++) {
708       new_map->init_req(i, in(i));
709     }
710     new_jvms->set_map(new_map);
711   } else {
712     new_jvms = new (phase->C) JVMState(0);
713     new_map = new SafePointNode(TypeFunc::Parms, new_jvms);
714     new_jvms->set_map(new_map);
715   }
716   new_map->set_control(in(TypeFunc::Control));
717   new_map->set_memory(MergeMemNode::make(in(TypeFunc::Memory)));
718   new_map->set_i_o(in(TypeFunc::I_O));
719   phase->record_for_igvn(new_map);
720 
721   GraphKit kit(new_jvms, phase);
722 
723   SafePointNode* backward_map = nullptr;
724   SafePointNode* forward_map = nullptr;
725   Node* backward_ctl = phase->C->top();
726 
727   array_copy_test_overlap(kit, disjoint_bases, count, backward_ctl);
728 
729   {
730     PreserveJVMState pjvms(&kit);
731 
732     array_copy_forward(kit, can_reshape,
733                        atp_src, atp_dest,
734                        adr_src, base_src, adr_dest, base_dest,
735                        copy_type, value_type, count);
736 
737     forward_map = kit.stop();
738   }
739 
740   kit.set_control(backward_ctl);
741   array_copy_backward(kit, can_reshape,
742                       atp_src, atp_dest,
743                       adr_src, base_src, adr_dest, base_dest,
744                       copy_type, value_type, count);
745 
746   backward_map = kit.stop();
747 
748   if (!forward_map->control()->is_top() && !backward_map->control()->is_top()) {
749     assert(forward_map->i_o() == backward_map->i_o(), "need a phi on IO?");
750     Node* ctl = new RegionNode(3);
751     Node* mem = new PhiNode(ctl, Type::MEMORY, TypePtr::BOTTOM);
752     kit.set_map(forward_map);
753     ctl->init_req(1, kit.control());
754     mem->init_req(1, kit.reset_memory());
755     kit.set_map(backward_map);
756     ctl->init_req(2, kit.control());
757     mem->init_req(2, kit.reset_memory());
758     kit.set_control(phase->transform(ctl));
759     kit.set_all_memory(phase->transform(mem));
760   } else if (!forward_map->control()->is_top()) {
761     kit.set_map(forward_map);
762   } else {
763     assert(!backward_map->control()->is_top(), "no copy?");
764     kit.set_map(backward_map);
765   }
766 
767   if (can_reshape) {
768     assert(phase->is_IterGVN()->delay_transform(), "should be delaying transforms");
769     phase->is_IterGVN()->set_delay_transform(false);
770   }
771 
772   mem = kit.map()->memory();
773   if (!finish_transform(phase, can_reshape, kit.control(), mem)) {
774     if (!can_reshape) {
775       phase->record_for_igvn(this);
776     } else {
777       // put in worklist, so that if it happens to be dead it is removed
778       phase->is_IterGVN()->_worklist.push(mem);
779     }
780     return nullptr;
781   }
782 
783   return mem;
784 }
785 
786 bool ArrayCopyNode::may_modify(const TypeOopPtr* t_oop, PhaseValues* phase) const {
787   Node* dest = in(ArrayCopyNode::Dest);
788   if (dest->is_top()) {
789     return false;
790   }
791   const TypeOopPtr* dest_t = phase->type(dest)->is_oopptr();
792   assert(!dest_t->is_known_instance() || _dest_type->is_known_instance(), "result of EA not recorded");
793   assert(in(ArrayCopyNode::Src)->is_top() || !phase->type(in(ArrayCopyNode::Src))->is_oopptr()->is_known_instance() ||
794          _src_type->is_known_instance(), "result of EA not recorded");
795 
796   if (_dest_type != TypeOopPtr::BOTTOM || t_oop->is_known_instance()) {
797     assert(_dest_type == TypeOopPtr::BOTTOM || _dest_type->is_known_instance(), "result of EA is known instance");
798     return t_oop->instance_id() == _dest_type->instance_id();
799   }
800 
801   return CallNode::may_modify_arraycopy_helper(dest_t, t_oop, phase);
802 }
803 
804 bool ArrayCopyNode::may_modify_helper(const TypeOopPtr* t_oop, Node* n, PhaseValues* phase, ArrayCopyNode*& ac) {
805   if (n != nullptr &&
806       n->is_ArrayCopy() &&
807       n->as_ArrayCopy()->may_modify(t_oop, phase)) {
808     ac = n->as_ArrayCopy();
809     return true;
810   }
811   return false;
812 }
813 
814 bool ArrayCopyNode::may_modify(const TypeOopPtr* t_oop, MemBarNode* mb, PhaseValues* phase, ArrayCopyNode*& ac) {
815   if (mb->trailing_expanded_array_copy()) {
816     return true;
817   }
818 
819   Node* c = mb->in(0);
820 
821   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
822   // step over g1 gc barrier if we're at e.g. a clone with ReduceInitialCardMarks off
823   c = bs->step_over_gc_barrier(c);
824 
825   CallNode* call = nullptr;
826   guarantee(c != nullptr, "step_over_gc_barrier failed, there must be something to step to.");
827   if (c->is_Region()) {
828     for (uint i = 1; i < c->req(); i++) {
829       if (c->in(i) != nullptr) {
830         Node* n = c->in(i)->in(0);
831         if (may_modify_helper(t_oop, n, phase, ac)) {
832           assert(c == mb->in(0), "only for clone");
833           return true;
834         }
835       }
836     }
837   } else if (may_modify_helper(t_oop, c->in(0), phase, ac)) {
838 #ifdef ASSERT
839     bool use_ReduceInitialCardMarks = BarrierSet::barrier_set()->is_a(BarrierSet::CardTableBarrierSet) &&
840       static_cast<CardTableBarrierSetC2*>(bs)->use_ReduceInitialCardMarks();
841     assert(c == mb->in(0) || (ac->is_clonebasic() && !use_ReduceInitialCardMarks), "only for clone");
842 #endif
843     return true;
844   }
845 
846   return false;
847 }
848 
849 // Does this array copy modify offsets between offset_lo and offset_hi
850 // in the destination array
851 // if must_modify is false, return true if the copy could write
852 // between offset_lo and offset_hi
853 // if must_modify is true, return true if the copy is guaranteed to
854 // write between offset_lo and offset_hi
855 bool ArrayCopyNode::modifies(intptr_t offset_lo, intptr_t offset_hi, PhaseValues* phase, bool must_modify) const {
856   assert(_kind == ArrayCopy || _kind == CopyOf || _kind == CopyOfRange, "only for real array copies");
857 
858   Node* dest = in(Dest);
859   Node* dest_pos = in(DestPos);
860   Node* len = in(Length);
861 
862   const TypeInt *dest_pos_t = phase->type(dest_pos)->isa_int();
863   const TypeInt *len_t = phase->type(len)->isa_int();
864   const TypeAryPtr* ary_t = phase->type(dest)->isa_aryptr();
865 
866   if (dest_pos_t == nullptr || len_t == nullptr || ary_t == nullptr) {
867     return !must_modify;
868   }
869 
870   BasicType ary_elem = ary_t->isa_aryptr()->elem()->array_element_basic_type();
871   if (is_reference_type(ary_elem, true)) ary_elem = T_OBJECT;
872 
873   uint header;
874   uint elem_size;
875   if (ary_t->is_flat()) {
876     header = arrayOopDesc::base_offset_in_bytes(T_FLAT_ELEMENT);
877     elem_size = ary_t->flat_elem_size();
878   } else {
879     header = arrayOopDesc::base_offset_in_bytes(ary_elem);
880     elem_size = type2aelembytes(ary_elem);
881   }
882 
883   jlong dest_pos_plus_len_lo = (((jlong)dest_pos_t->_lo) + len_t->_lo) * elem_size + header;
884   jlong dest_pos_plus_len_hi = (((jlong)dest_pos_t->_hi) + len_t->_hi) * elem_size + header;
885   jlong dest_pos_lo = ((jlong)dest_pos_t->_lo) * elem_size + header;
886   jlong dest_pos_hi = ((jlong)dest_pos_t->_hi) * elem_size + header;
887 
888   if (must_modify) {
889     if (offset_lo >= dest_pos_hi && offset_hi < dest_pos_plus_len_lo) {
890       return true;
891     }
892   } else {
893     if (offset_hi >= dest_pos_lo && offset_lo < dest_pos_plus_len_hi) {
894       return true;
895     }
896   }
897   return false;
898 }
899 
900 // As an optimization, choose the optimal vector size for bounded copy length
901 int ArrayCopyNode::get_partial_inline_vector_lane_count(BasicType type, jlong max_len) {
902   assert(max_len > 0, JLONG_FORMAT, max_len);
903   // We only care whether max_size_in_bytes is not larger than 32, we also want to avoid
904   // multiplication overflow, so clamp max_len to [0, 64]
905   int max_size_in_bytes = MIN2<jlong>(max_len, 64) * type2aelembytes(type);
906   if (ArrayOperationPartialInlineSize > 16 && max_size_in_bytes <= 16) {
907     return 16 / type2aelembytes(type);
908   } else if (ArrayOperationPartialInlineSize > 32 && max_size_in_bytes <= 32) {
909     return 32 / type2aelembytes(type);
910   } else {
911     return ArrayOperationPartialInlineSize / type2aelembytes(type);
912   }
913 }