1 /*
  2  * Copyright (c) 2016, 2025, 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* base_src = in(ArrayCopyNode::Src);
191   Node* base_dest = in(ArrayCopyNode::Dest);
192   Node* ctl = in(TypeFunc::Control);
193   Node* in_mem = in(TypeFunc::Memory);
194 
195   const Type* src_type = phase->type(base_src);
196   const TypeInstPtr* inst_src = src_type->isa_instptr();
197   if (inst_src == nullptr) {
198     return nullptr;
199   }
200 
201   MergeMemNode* mem = phase->transform(MergeMemNode::make(in_mem))->as_MergeMem();
202   phase->record_for_igvn(mem);
203   if (can_reshape) {
204     phase->is_IterGVN()->_worklist.push(mem);
205   }
206 
207 
208   ciInstanceKlass* ik = inst_src->instance_klass();
209 
210   if (!inst_src->klass_is_exact()) {
211     assert(!ik->is_interface(), "inconsistent klass hierarchy");
212     if (ik->has_subklass()) {
213       // Concurrent class loading.
214       // Fail fast and return NodeSentinel to indicate that the transform failed.
215       return NodeSentinel;
216     } else {
217       phase->C->dependencies()->assert_leaf_type(ik);
218     }
219   }
220 
221   const TypeInstPtr* dest_type = phase->type(base_dest)->is_instptr();
222   if (dest_type->instance_klass() != ik) {
223     // At parse time, the exact type of the object to clone was not known. That inexact type was captured by the CheckCastPP
224     // of the newly allocated cloned object (in dest). The exact type is now known (in src), but the type for the cloned object
225     // (dest) was not updated. When copying the fields below, Store nodes may write to offsets for fields that don't exist in
226     // the inexact class. The stores would then be assigned an incorrect slice.
227     return NodeSentinel;
228   }
229 
230   assert(ik->nof_nonstatic_fields() <= ArrayCopyLoadStoreMaxElem, "too many fields");
231 
232   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
233   for (int i = 0; i < count; i++) {
234     ciField* field = ik->nonstatic_field_at(i);
235     const TypePtr* adr_type = phase->C->alias_type(field)->adr_type();
236     Node* off = phase->MakeConX(field->offset_in_bytes());
237     Node* next_src = phase->transform(new AddPNode(base_src,base_src,off));
238     Node* next_dest = phase->transform(new AddPNode(base_dest,base_dest,off));
239     assert(phase->C->get_alias_index(adr_type) == phase->C->get_alias_index(phase->type(next_src)->isa_ptr()),
240       "slice of address and input slice don't match");
241     assert(phase->C->get_alias_index(adr_type) == phase->C->get_alias_index(phase->type(next_dest)->isa_ptr()),
242       "slice of address and input slice don't match");
243     BasicType bt = field->layout_type();
244 
245     const Type *type;
246     if (bt == T_OBJECT) {
247       if (!field->type()->is_loaded()) {
248         type = TypeInstPtr::BOTTOM;
249       } else {
250         ciType* field_klass = field->type();
251         type = TypeOopPtr::make_from_klass(field_klass->as_klass());
252       }
253     } else {
254       type = Type::get_const_basic_type(bt);
255     }
256 
257     Node* v = load(bs, phase, ctl, mem, next_src, adr_type, type, bt);
258     store(bs, phase, ctl, mem, next_dest, adr_type, v, type, bt);
259   }
260 
261   if (!finish_transform(phase, can_reshape, ctl, mem)) {
262     // Return NodeSentinel to indicate that the transform failed
263     return NodeSentinel;
264   }
265 
266   return mem;
267 }
268 
269 bool ArrayCopyNode::prepare_array_copy(PhaseGVN *phase, bool can_reshape,
270                                        Node*& adr_src,
271                                        Node*& base_src,
272                                        Node*& adr_dest,
273                                        Node*& base_dest,
274                                        BasicType& copy_type,
275                                        const Type*& value_type,
276                                        bool& disjoint_bases) {
277   base_src = in(ArrayCopyNode::Src);
278   base_dest = in(ArrayCopyNode::Dest);
279   const Type* src_type = phase->type(base_src);
280   const TypeAryPtr* ary_src = src_type->isa_aryptr();
281 
282   Node* src_offset = in(ArrayCopyNode::SrcPos);
283   Node* dest_offset = in(ArrayCopyNode::DestPos);
284 
285   if (is_arraycopy() || is_copyofrange() || is_copyof()) {
286     const Type* dest_type = phase->type(base_dest);
287     const TypeAryPtr* ary_dest = dest_type->isa_aryptr();
288 
289     // newly allocated object is guaranteed to not overlap with source object
290     disjoint_bases = is_alloc_tightly_coupled();
291     if (ary_src  == nullptr || ary_src->elem()  == Type::BOTTOM ||
292         ary_dest == nullptr || ary_dest->elem() == Type::BOTTOM) {
293       // We don't know if arguments are arrays
294       return false;
295     }
296 
297     BasicType src_elem = ary_src->elem()->array_element_basic_type();
298     BasicType dest_elem = ary_dest->elem()->array_element_basic_type();
299     if (is_reference_type(src_elem, true)) src_elem = T_OBJECT;
300     if (is_reference_type(dest_elem, true)) dest_elem = T_OBJECT;
301 
302     // TODO 8350865 What about atomicity?
303     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) {
304       // We don't know if arguments are arrays of the same type
305       return false;
306     }
307 
308     BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
309     if ((!ary_dest->is_flat() && bs->array_copy_requires_gc_barriers(is_alloc_tightly_coupled(), dest_elem, false, false, BarrierSetC2::Optimization)) ||
310         (ary_dest->is_flat() && ary_src->elem()->inline_klass()->contains_oops() &&
311          bs->array_copy_requires_gc_barriers(is_alloc_tightly_coupled(), T_OBJECT, false, false, BarrierSetC2::Optimization))) {
312       // It's an object array copy but we can't emit the card marking that is needed
313       return false;
314     }
315 
316     value_type = ary_src->elem();
317 
318     uint shift  = exact_log2(type2aelembytes(dest_elem));
319     if (ary_dest->is_flat()) {
320       assert(ary_src->is_flat(), "src and dest must be flat");
321       shift = ary_src->flat_log_elem_size();
322       src_elem = T_FLAT_ELEMENT;
323       dest_elem = T_FLAT_ELEMENT;
324     }
325 
326     const uint header = arrayOopDesc::base_offset_in_bytes(dest_elem);
327 
328     src_offset = Compile::conv_I2X_index(phase, src_offset, ary_src->size());
329     if (src_offset->is_top()) {
330       // Offset is out of bounds (the ArrayCopyNode will be removed)
331       return false;
332     }
333     dest_offset = Compile::conv_I2X_index(phase, dest_offset, ary_dest->size());
334     if (dest_offset->is_top()) {
335       // Offset is out of bounds (the ArrayCopyNode will be removed)
336       if (can_reshape) {
337         // record src_offset, so it can be deleted later (if it is dead)
338         phase->is_IterGVN()->_worklist.push(src_offset);
339       }
340       return false;
341     }
342 
343     Node* hook = new Node(1);
344     hook->init_req(0, dest_offset);
345 
346     Node* src_scale  = phase->transform(new LShiftXNode(src_offset, phase->intcon(shift)));
347 
348     hook->destruct(phase);
349 
350     Node* dest_scale = phase->transform(new LShiftXNode(dest_offset, phase->intcon(shift)));
351 
352     adr_src          = phase->transform(new AddPNode(base_src, base_src, src_scale));
353     adr_dest         = phase->transform(new AddPNode(base_dest, base_dest, dest_scale));
354 
355     adr_src          = phase->transform(new AddPNode(base_src, adr_src, phase->MakeConX(header)));
356     adr_dest         = phase->transform(new AddPNode(base_dest, adr_dest, phase->MakeConX(header)));
357 
358     copy_type = dest_elem;
359   } else {
360     assert(ary_src != nullptr, "should be a clone");
361     assert(is_clonebasic(), "should be");
362 
363     disjoint_bases = true;
364 
365     if (ary_src->elem()->make_oopptr() != nullptr &&
366         ary_src->elem()->make_oopptr()->can_be_inline_type()) {
367       return false;
368     }
369 
370     BasicType elem = ary_src->isa_aryptr()->elem()->array_element_basic_type();
371     if (is_reference_type(elem, true)) {
372       elem = T_OBJECT;
373     }
374 
375     BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
376     if ((!ary_src->is_flat() && bs->array_copy_requires_gc_barriers(true, elem, true, is_clone_inst(), BarrierSetC2::Optimization)) ||
377         (ary_src->is_flat() && ary_src->elem()->inline_klass()->contains_oops() &&
378          bs->array_copy_requires_gc_barriers(true, T_OBJECT, true, is_clone_inst(), BarrierSetC2::Optimization))) {
379       // It's an object array copy but we can't emit the card marking that is needed
380       return false;
381     }
382 
383     adr_src  = phase->transform(new AddPNode(base_src, base_src, src_offset));
384     adr_dest = phase->transform(new AddPNode(base_dest, base_dest, dest_offset));
385 
386     // The address is offsetted to an aligned address where a raw copy would start.
387     // If the clone copy is decomposed into load-stores - the address is adjusted to
388     // point at where the array starts.
389     const Type* toff = phase->type(src_offset);
390     int offset = toff->isa_long() ? (int) toff->is_long()->get_con() : (int) toff->is_int()->get_con();
391     int diff = arrayOopDesc::base_offset_in_bytes(elem) - offset;
392     assert(diff >= 0, "clone should not start after 1st array element");
393     if (diff > 0) {
394       adr_src = phase->transform(new AddPNode(base_src, adr_src, phase->MakeConX(diff)));
395       adr_dest = phase->transform(new AddPNode(base_dest, adr_dest, phase->MakeConX(diff)));
396     }
397     copy_type = elem;
398     value_type = ary_src->elem();
399   }
400   return true;
401 }
402 
403 const TypeAryPtr* ArrayCopyNode::get_address_type(PhaseGVN* phase, const TypePtr* atp, Node* n) {
404   if (atp == TypeOopPtr::BOTTOM) {
405     atp = phase->type(n)->isa_ptr();
406   }
407   // adjust atp to be the correct array element address type
408   return atp->add_offset(Type::OffsetBot)->is_aryptr();
409 }
410 
411 void ArrayCopyNode::array_copy_test_overlap(GraphKit& kit, bool disjoint_bases, int count, Node*& backward_ctl) {
412   Node* ctl = kit.control();
413   if (!disjoint_bases && count > 1) {
414     PhaseGVN& gvn = kit.gvn();
415     Node* src_offset = in(ArrayCopyNode::SrcPos);
416     Node* dest_offset = in(ArrayCopyNode::DestPos);
417     assert(src_offset != nullptr && dest_offset != nullptr, "should be");
418     Node* cmp = gvn.transform(new CmpINode(src_offset, dest_offset));
419     Node *bol = gvn.transform(new BoolNode(cmp, BoolTest::lt));
420     IfNode *iff = new IfNode(ctl, bol, PROB_FAIR, COUNT_UNKNOWN);
421 
422     gvn.transform(iff);
423 
424     kit.set_control(gvn.transform(new IfFalseNode(iff)));
425     backward_ctl = gvn.transform(new IfTrueNode(iff));
426   }
427 }
428 
429 void ArrayCopyNode::copy(GraphKit& kit,
430                          const TypeAryPtr* atp_src,
431                          const TypeAryPtr* atp_dest,
432                          int i,
433                          Node* base_src,
434                          Node* base_dest,
435                          Node* adr_src,
436                          Node* adr_dest,
437                          BasicType copy_type,
438                          const Type* value_type) {
439   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
440   Node* ctl = kit.control();
441   if (atp_dest->is_flat()) {
442     ciInlineKlass* vk = atp_src->elem()->inline_klass();
443     for (int j = 0; j < vk->nof_nonstatic_fields(); j++) {
444       ciField* field = vk->nonstatic_field_at(j);
445       int off_in_vt = field->offset_in_bytes() - vk->payload_offset();
446       Node* off  = kit.MakeConX(off_in_vt + i * atp_src->flat_elem_size());
447       ciType* ft = field->type();
448       BasicType bt = type2field[ft->basic_type()];
449       assert(!field->is_flat(), "flat field encountered");
450       const Type* rt = Type::get_const_type(ft);
451       const TypePtr* adr_type = atp_src->with_field_offset(off_in_vt)->add_offset(Type::OffsetBot);
452       assert(!bs->array_copy_requires_gc_barriers(is_alloc_tightly_coupled(), bt, false, false, BarrierSetC2::Optimization), "GC barriers required");
453       Node* next_src = kit.gvn().transform(new AddPNode(base_src, adr_src, off));
454       Node* next_dest = kit.gvn().transform(new AddPNode(base_dest, adr_dest, off));
455       Node* v = load(bs, &kit.gvn(), ctl, kit.merged_memory(), next_src, adr_type, rt, bt);
456       store(bs, &kit.gvn(), ctl, kit.merged_memory(), next_dest, adr_type, v, rt, bt);
457     }
458   } else {
459     Node* off = kit.MakeConX(type2aelembytes(copy_type) * i);
460     Node* next_src = kit.gvn().transform(new AddPNode(base_src, adr_src, off));
461     Node* next_dest = kit.gvn().transform(new AddPNode(base_dest, adr_dest, off));
462     Node* v = load(bs, &kit.gvn(), ctl, kit.merged_memory(), next_src, atp_src, value_type, copy_type);
463     store(bs, &kit.gvn(), ctl, kit.merged_memory(), next_dest, atp_dest, v, value_type, copy_type);
464   }
465   kit.set_control(ctl);
466 }
467 
















468 
469 void ArrayCopyNode::array_copy_forward(GraphKit& kit,
470                                        bool can_reshape,
471                                        const TypeAryPtr* atp_src,
472                                        const TypeAryPtr* atp_dest,
473                                        Node* adr_src,
474                                        Node* base_src,
475                                        Node* adr_dest,
476                                        Node* base_dest,
477                                        BasicType copy_type,
478                                        const Type* value_type,
479                                        int count) {
480   if (!kit.stopped()) {
481     // copy forward
482     if (count > 0) {
483       for (int i = 0; i < count; i++) {
484         copy(kit, atp_src, atp_dest, i, base_src, base_dest, adr_src, adr_dest, copy_type, value_type);







485       }
486     } else if (can_reshape) {
487       PhaseGVN& gvn = kit.gvn();
488       assert(gvn.is_IterGVN(), "");
489       gvn.record_for_igvn(adr_src);
490       gvn.record_for_igvn(adr_dest);
491     }

492   }

493 }
494 
495 void ArrayCopyNode::array_copy_backward(GraphKit& kit,
496                                         bool can_reshape,
497                                         const TypeAryPtr* atp_src,
498                                         const TypeAryPtr* atp_dest,
499                                         Node* adr_src,
500                                         Node* base_src,
501                                         Node* adr_dest,
502                                         Node* base_dest,
503                                         BasicType copy_type,
504                                         const Type* value_type,
505                                         int count) {
506   if (!kit.stopped()) {


507     // copy backward
508     PhaseGVN& gvn = kit.gvn();



509 
510     if (count > 0) {
511       for (int i = count-1; i >= 0; i--) {
512         copy(kit, atp_src, atp_dest, i, base_src, base_dest, adr_src, adr_dest, copy_type, value_type);




513       }
514     } else if(can_reshape) {
515       PhaseGVN& gvn = kit.gvn();
516       assert(gvn.is_IterGVN(), "");
517       gvn.record_for_igvn(adr_src);
518       gvn.record_for_igvn(adr_dest);

519     }

520   }

521 }
522 
523 bool ArrayCopyNode::finish_transform(PhaseGVN *phase, bool can_reshape,
524                                      Node* ctl, Node *mem) {
525   if (can_reshape) {
526     PhaseIterGVN* igvn = phase->is_IterGVN();
527     igvn->set_delay_transform(false);
528     if (is_clonebasic()) {
529       Node* out_mem = proj_out(TypeFunc::Memory);
530 
531       BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
532       if (out_mem->outcnt() != 1 || !out_mem->raw_out(0)->is_MergeMem() ||
533           out_mem->raw_out(0)->outcnt() != 1 || !out_mem->raw_out(0)->raw_out(0)->is_MemBar()) {
534         assert(bs->array_copy_requires_gc_barriers(true, T_OBJECT, true, is_clone_inst(), BarrierSetC2::Optimization), "can only happen with card marking");
535         return false;
536       }
537 
538       igvn->replace_node(out_mem->raw_out(0), mem);
539 
540       Node* out_ctl = proj_out(TypeFunc::Control);
541       igvn->replace_node(out_ctl, ctl);
542     } else {
543       // replace fallthrough projections of the ArrayCopyNode by the
544       // new memory, control and the input IO.
545       CallProjections* callprojs = extract_projections(true, false);

546 
547       if (callprojs->fallthrough_ioproj != nullptr) {
548         igvn->replace_node(callprojs->fallthrough_ioproj, in(TypeFunc::I_O));
549       }
550       if (callprojs->fallthrough_memproj != nullptr) {
551         igvn->replace_node(callprojs->fallthrough_memproj, mem);
552       }
553       if (callprojs->fallthrough_catchproj != nullptr) {
554         igvn->replace_node(callprojs->fallthrough_catchproj, ctl);
555       }
556 
557       // The ArrayCopyNode is not disconnected. It still has the
558       // projections for the exception case. Replace current
559       // ArrayCopyNode with a dummy new one with a top() control so
560       // that this part of the graph stays consistent but is
561       // eventually removed.
562 
563       set_req(0, phase->C->top());
564       remove_dead_region(phase, can_reshape);
565     }
566   } else {
567     if (in(TypeFunc::Control) != ctl) {
568       // we can't return new memory and control from Ideal at parse time
569       assert(!is_clonebasic() || UseShenandoahGC, "added control for clone?");
570       phase->record_for_igvn(this);
571       return false;
572     }
573   }
574   return true;
575 }
576 
577 
578 Node *ArrayCopyNode::Ideal(PhaseGVN *phase, bool can_reshape) {
579   // Perform any generic optimizations first
580   Node* result = SafePointNode::Ideal(phase, can_reshape);
581   if (result != nullptr) {
582     return result;
583   }
584 
585   if (StressArrayCopyMacroNode && !can_reshape) {
586     phase->record_for_igvn(this);
587     return nullptr;
588   }
589 
590   // See if it's a small array copy and we can inline it as
591   // loads/stores
592   // Here we can only do:
593   // - arraycopy if all arguments were validated before and we don't
594   // need card marking
595   // - clone for which we don't need to do card marking
596 
597   if (!is_clonebasic() && !is_arraycopy_validated() &&
598       !is_copyofrange_validated() && !is_copyof_validated()) {
599     return nullptr;
600   }
601 
602   assert(in(TypeFunc::Control) != nullptr &&
603          in(TypeFunc::Memory) != nullptr &&
604          in(ArrayCopyNode::Src) != nullptr &&
605          in(ArrayCopyNode::Dest) != nullptr &&
606          in(ArrayCopyNode::Length) != nullptr &&
607          in(ArrayCopyNode::SrcPos) != nullptr &&
608          in(ArrayCopyNode::DestPos) != nullptr, "broken inputs");
609 
610   if (in(TypeFunc::Control)->is_top() ||
611       in(TypeFunc::Memory)->is_top() ||
612       phase->type(in(ArrayCopyNode::Src)) == Type::TOP ||
613       phase->type(in(ArrayCopyNode::Dest)) == Type::TOP ||
614       (in(ArrayCopyNode::SrcPos) != nullptr && in(ArrayCopyNode::SrcPos)->is_top()) ||
615       (in(ArrayCopyNode::DestPos) != nullptr && in(ArrayCopyNode::DestPos)->is_top())) {
616     return nullptr;
617   }
618 
619   int count = get_count(phase);
620 
621   if (count < 0 || count > ArrayCopyLoadStoreMaxElem) {
622     return nullptr;
623   }
624 
625   Node* src = in(ArrayCopyNode::Src);
626   Node* dest = in(ArrayCopyNode::Dest);
627   const Type* src_type = phase->type(src);
628   const Type* dest_type = phase->type(dest);
629 
630   if (src_type->isa_aryptr() && dest_type->isa_instptr()) {
631     // clone used for load of unknown inline type can't be optimized at
632     // this point
633     return nullptr;
634   }
635 
636   Node* mem = try_clone_instance(phase, can_reshape, count);
637   if (mem != nullptr) {
638     return (mem == NodeSentinel) ? nullptr : mem;
639   }
640 
641   Node* adr_src = nullptr;
642   Node* base_src = nullptr;
643   Node* adr_dest = nullptr;
644   Node* base_dest = nullptr;
645   BasicType copy_type = T_ILLEGAL;
646   const Type* value_type = nullptr;
647   bool disjoint_bases = false;
648 
649   if (!prepare_array_copy(phase, can_reshape,
650                           adr_src, base_src, adr_dest, base_dest,
651                           copy_type, value_type, disjoint_bases)) {
652     assert(adr_src == nullptr, "no node can be left behind");
653     assert(adr_dest == nullptr, "no node can be left behind");
654     return nullptr;
655   }
656 
657   JVMState* new_jvms = nullptr;
658   SafePointNode* new_map = nullptr;
659   if (!is_clonebasic()) {
660     new_jvms = jvms()->clone_shallow(phase->C);
661     new_map = new SafePointNode(req(), new_jvms);
662     for (uint i = TypeFunc::FramePtr; i < req(); i++) {
663       new_map->init_req(i, in(i));
664     }
665     new_jvms->set_map(new_map);
666   } else {
667     new_jvms = new (phase->C) JVMState(0);
668     new_map = new SafePointNode(TypeFunc::Parms, new_jvms);
669     new_jvms->set_map(new_map);
670   }
671   new_map->set_control(in(TypeFunc::Control));
672   new_map->set_memory(MergeMemNode::make(in(TypeFunc::Memory)));
673   new_map->set_i_o(in(TypeFunc::I_O));
674   phase->record_for_igvn(new_map);
675 
676   const TypeAryPtr* atp_src = get_address_type(phase, _src_type, src);
677   const TypeAryPtr* atp_dest = get_address_type(phase, _dest_type, dest);
678 
679   if (can_reshape) {
680     assert(!phase->is_IterGVN()->delay_transform(), "cannot delay transforms");
681     phase->is_IterGVN()->set_delay_transform(true);
682   }
683 
684   GraphKit kit(new_jvms, phase);
685 
686   SafePointNode* backward_map = nullptr;
687   SafePointNode* forward_map = nullptr;
688   Node* backward_ctl = phase->C->top();
689 
690   array_copy_test_overlap(kit, disjoint_bases, count, backward_ctl);
691 
692   {
693     PreserveJVMState pjvms(&kit);
694 
695     array_copy_forward(kit, can_reshape,
696                        atp_src, atp_dest,
697                        adr_src, base_src, adr_dest, base_dest,
698                        copy_type, value_type, count);
699 
700     forward_map = kit.stop();
701   }
702 
703   kit.set_control(backward_ctl);
704   array_copy_backward(kit, can_reshape,
705                       atp_src, atp_dest,
706                       adr_src, base_src, adr_dest, base_dest,
707                       copy_type, value_type, count);
708 
709   backward_map = kit.stop();
710 
711   if (!forward_map->control()->is_top() && !backward_map->control()->is_top()) {
712     assert(forward_map->i_o() == backward_map->i_o(), "need a phi on IO?");
713     Node* ctl = new RegionNode(3);
714     Node* mem = new PhiNode(ctl, Type::MEMORY, TypePtr::BOTTOM);
715     kit.set_map(forward_map);
716     ctl->init_req(1, kit.control());
717     mem->init_req(1, kit.reset_memory());
718     kit.set_map(backward_map);
719     ctl->init_req(2, kit.control());
720     mem->init_req(2, kit.reset_memory());
721     kit.set_control(phase->transform(ctl));
722     kit.set_all_memory(phase->transform(mem));
723   } else if (!forward_map->control()->is_top()) {
724     kit.set_map(forward_map);
725   } else {
726     assert(!backward_map->control()->is_top(), "no copy?");
727     kit.set_map(backward_map);

728   }
729 
730   if (can_reshape) {
731     assert(phase->is_IterGVN()->delay_transform(), "should be delaying transforms");
732     phase->is_IterGVN()->set_delay_transform(false);
733   }
734 
735   mem = kit.map()->memory();
736   if (!finish_transform(phase, can_reshape, kit.control(), mem)) {
737     if (!can_reshape) {
738       phase->record_for_igvn(this);
739     } else {
740       // put in worklist, so that if it happens to be dead it is removed
741       phase->is_IterGVN()->_worklist.push(mem);
742     }
743     return nullptr;
744   }
745 
746   return mem;
747 }
748 
749 bool ArrayCopyNode::may_modify(const TypeOopPtr* t_oop, PhaseValues* phase) {
750   Node* dest = in(ArrayCopyNode::Dest);
751   if (dest->is_top()) {
752     return false;
753   }
754   const TypeOopPtr* dest_t = phase->type(dest)->is_oopptr();
755   assert(!dest_t->is_known_instance() || _dest_type->is_known_instance(), "result of EA not recorded");
756   assert(in(ArrayCopyNode::Src)->is_top() || !phase->type(in(ArrayCopyNode::Src))->is_oopptr()->is_known_instance() ||
757          _src_type->is_known_instance(), "result of EA not recorded");
758 
759   if (_dest_type != TypeOopPtr::BOTTOM || t_oop->is_known_instance()) {
760     assert(_dest_type == TypeOopPtr::BOTTOM || _dest_type->is_known_instance(), "result of EA is known instance");
761     return t_oop->instance_id() == _dest_type->instance_id();
762   }
763 
764   return CallNode::may_modify_arraycopy_helper(dest_t, t_oop, phase);
765 }
766 
767 bool ArrayCopyNode::may_modify_helper(const TypeOopPtr* t_oop, Node* n, PhaseValues* phase, ArrayCopyNode*& ac) {
768   if (n != nullptr &&
769       n->is_ArrayCopy() &&
770       n->as_ArrayCopy()->may_modify(t_oop, phase)) {
771     ac = n->as_ArrayCopy();
772     return true;
773   }
774   return false;
775 }
776 
777 bool ArrayCopyNode::may_modify(const TypeOopPtr* t_oop, MemBarNode* mb, PhaseValues* phase, ArrayCopyNode*& ac) {
778   if (mb->trailing_expanded_array_copy()) {
779     return true;
780   }
781 
782   Node* c = mb->in(0);
783 
784   BarrierSetC2* bs = BarrierSet::barrier_set()->barrier_set_c2();
785   // step over g1 gc barrier if we're at e.g. a clone with ReduceInitialCardMarks off
786   c = bs->step_over_gc_barrier(c);
787 
788   CallNode* call = nullptr;
789   guarantee(c != nullptr, "step_over_gc_barrier failed, there must be something to step to.");
790   if (c->is_Region()) {
791     for (uint i = 1; i < c->req(); i++) {
792       if (c->in(i) != nullptr) {
793         Node* n = c->in(i)->in(0);
794         if (may_modify_helper(t_oop, n, phase, ac)) {
795           assert(c == mb->in(0), "only for clone");
796           return true;
797         }
798       }
799     }
800   } else if (may_modify_helper(t_oop, c->in(0), phase, ac)) {
801 #ifdef ASSERT
802     bool use_ReduceInitialCardMarks = BarrierSet::barrier_set()->is_a(BarrierSet::CardTableBarrierSet) &&
803       static_cast<CardTableBarrierSetC2*>(bs)->use_ReduceInitialCardMarks();
804     assert(c == mb->in(0) || (ac->is_clonebasic() && !use_ReduceInitialCardMarks), "only for clone");
805 #endif
806     return true;
807   }
808 
809   return false;
810 }
811 
812 // Does this array copy modify offsets between offset_lo and offset_hi
813 // in the destination array
814 // if must_modify is false, return true if the copy could write
815 // between offset_lo and offset_hi
816 // if must_modify is true, return true if the copy is guaranteed to
817 // write between offset_lo and offset_hi
818 bool ArrayCopyNode::modifies(intptr_t offset_lo, intptr_t offset_hi, PhaseValues* phase, bool must_modify) const {
819   assert(_kind == ArrayCopy || _kind == CopyOf || _kind == CopyOfRange, "only for real array copies");
820 
821   Node* dest = in(Dest);
822   Node* dest_pos = in(DestPos);
823   Node* len = in(Length);
824 
825   const TypeInt *dest_pos_t = phase->type(dest_pos)->isa_int();
826   const TypeInt *len_t = phase->type(len)->isa_int();
827   const TypeAryPtr* ary_t = phase->type(dest)->isa_aryptr();
828 
829   if (dest_pos_t == nullptr || len_t == nullptr || ary_t == nullptr) {
830     return !must_modify;
831   }
832 
833   BasicType ary_elem = ary_t->isa_aryptr()->elem()->array_element_basic_type();
834   if (is_reference_type(ary_elem, true)) ary_elem = T_OBJECT;
835 
836   uint header;
837   uint elem_size;
838   if (ary_t->is_flat()) {
839     header = arrayOopDesc::base_offset_in_bytes(T_FLAT_ELEMENT);
840     elem_size = ary_t->flat_elem_size();
841   } else {
842     header = arrayOopDesc::base_offset_in_bytes(ary_elem);
843     elem_size = type2aelembytes(ary_elem);
844   }
845 
846   jlong dest_pos_plus_len_lo = (((jlong)dest_pos_t->_lo) + len_t->_lo) * elem_size + header;
847   jlong dest_pos_plus_len_hi = (((jlong)dest_pos_t->_hi) + len_t->_hi) * elem_size + header;
848   jlong dest_pos_lo = ((jlong)dest_pos_t->_lo) * elem_size + header;
849   jlong dest_pos_hi = ((jlong)dest_pos_t->_hi) * elem_size + header;
850 
851   if (must_modify) {
852     if (offset_lo >= dest_pos_hi && offset_hi < dest_pos_plus_len_lo) {
853       return true;
854     }
855   } else {
856     if (offset_hi >= dest_pos_lo && offset_lo < dest_pos_plus_len_hi) {
857       return true;
858     }
859   }
860   return false;
861 }
862 
863 // As an optimization, choose the optimal vector size for bounded copy length
864 int ArrayCopyNode::get_partial_inline_vector_lane_count(BasicType type, jlong max_len) {
865   assert(max_len > 0, JLONG_FORMAT, max_len);
866   // We only care whether max_size_in_bytes is not larger than 32, we also want to avoid
867   // multiplication overflow, so clamp max_len to [0, 64]
868   int max_size_in_bytes = MIN2<jlong>(max_len, 64) * type2aelembytes(type);
869   if (ArrayOperationPartialInlineSize > 16 && max_size_in_bytes <= 16) {
870     return 16 / type2aelembytes(type);
871   } else if (ArrayOperationPartialInlineSize > 32 && max_size_in_bytes <= 32) {
872     return 32 / type2aelembytes(type);
873   } else {
874     return ArrayOperationPartialInlineSize / type2aelembytes(type);
875   }
876 }
--- EOF ---