1 /*
  2  * Copyright (c) 2014, 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 "castnode.hpp"
 26 #include "opto/addnode.hpp"
 27 #include "opto/callnode.hpp"
 28 #include "opto/castnode.hpp"
 29 #include "opto/cfgnode.hpp"
 30 #include "opto/connode.hpp"
 31 #include "opto/graphKit.hpp"
 32 #include "opto/inlinetypenode.hpp"
 33 #include "opto/loopnode.hpp"
 34 #include "opto/matcher.hpp"
 35 #include "opto/phaseX.hpp"
 36 #include "opto/rootnode.hpp"
 37 #include "opto/subnode.hpp"
 38 #include "opto/type.hpp"
 39 #include "utilities/checkedCast.hpp"
 40 
 41 //=============================================================================
 42 // If input is already higher or equal to cast type, then this is an identity.
 43 Node* ConstraintCastNode::Identity(PhaseGVN* phase) {
 44   if (_dependency == UnconditionalDependency) {
 45     return this;
 46   }
 47   Node* dom = dominating_cast(phase, phase);
 48   if (dom != nullptr) {
 49     return dom;
 50   }
 51   return higher_equal_types(phase, in(1)) ? in(1) : this;
 52 }
 53 
 54 //------------------------------Value------------------------------------------
 55 // Take 'join' of input and cast-up type
 56 const Type* ConstraintCastNode::Value(PhaseGVN* phase) const {
 57   if (in(0) && phase->type(in(0)) == Type::TOP) return Type::TOP;
 58 
 59   const Type* in_type = phase->type(in(1));
 60   const Type* ft = in_type->filter_speculative(_type);
 61 
 62   // Check if both _type and in_type had a speculative type, but for the just
 63   // computed ft the speculative type was dropped.
 64   if (ft->speculative() == nullptr &&
 65       _type->speculative() != nullptr &&
 66       in_type->speculative() != nullptr) {
 67     // Speculative type may have disagreed between cast and input, and was
 68     // dropped in filtering. Recompute so that ft can take speculative type
 69     // of in_type. If we did not do it now, a subsequent ::Value call would
 70     // do it, and violate idempotence of ::Value.
 71     ft = in_type->filter_speculative(ft);
 72   }
 73 
 74 #ifdef ASSERT
 75   // Previous versions of this function had some special case logic,
 76   // which is no longer necessary.  Make sure of the required effects.
 77   switch (Opcode()) {
 78     case Op_CastII:
 79     {
 80       if (in_type == Type::TOP) {
 81         assert(ft == Type::TOP, "special case #1");
 82       }
 83       const Type* rt = in_type->join_speculative(_type);
 84       if (rt->empty()) {
 85         assert(ft == Type::TOP, "special case #2");
 86       }
 87       break;
 88     }
 89     case Op_CastPP:
 90     if (in_type == TypePtr::NULL_PTR &&
 91         _type->isa_ptr() && _type->is_ptr()->_ptr == TypePtr::NotNull) {
 92       assert(ft == Type::TOP, "special case #3");
 93       break;
 94     }
 95   }
 96 #endif //ASSERT
 97 
 98   return ft;
 99 }
100 
101 //------------------------------Ideal------------------------------------------
102 // Return a node which is more "ideal" than the current node.  Strip out
103 // control copies
104 Node *ConstraintCastNode::Ideal(PhaseGVN *phase, bool can_reshape) {
105   if (in(0) != nullptr && remove_dead_region(phase, can_reshape)) {
106     return this;
107   }
108 
109   // Push cast through InlineTypeNode
110   InlineTypeNode* vt = in(1)->isa_InlineType();
111   if (vt != nullptr && phase->type(vt)->filter_speculative(_type) != Type::TOP) {
112     Node* cast = clone();
113     cast->set_req(1, vt->get_oop());
114     vt = vt->clone()->as_InlineType();
115     if (!_type->maybe_null()) {
116       vt->as_InlineType()->set_null_marker(*phase);
117     }
118     vt->set_oop(*phase, phase->transform(cast));
119     return vt;
120   }
121 
122   if (in(1) != nullptr && phase->type(in(1)) != Type::TOP) {
123     return TypeNode::Ideal(phase, can_reshape);
124   }
125 
126   return nullptr;
127 }
128 
129 uint ConstraintCastNode::hash() const {
130   return TypeNode::hash() + (int)_dependency + (_extra_types != nullptr ? _extra_types->hash() : 0);
131 }
132 
133 bool ConstraintCastNode::cmp(const Node &n) const {
134   if (!TypeNode::cmp(n)) {
135     return false;
136   }
137   ConstraintCastNode& cast = (ConstraintCastNode&) n;
138   if (cast._dependency != _dependency) {
139     return false;
140   }
141   if (_extra_types == nullptr || cast._extra_types == nullptr) {
142     return _extra_types == cast._extra_types;
143   }
144   return _extra_types->eq(cast._extra_types);
145 }
146 
147 uint ConstraintCastNode::size_of() const {
148   return sizeof(*this);
149 }
150 
151 Node* ConstraintCastNode::make_cast_for_basic_type(Node* c, Node* n, const Type* t, DependencyType dependency, BasicType bt) {
152   switch(bt) {
153   case T_INT:
154     return new CastIINode(c, n, t, dependency);
155   case T_LONG:
156     return new CastLLNode(c, n, t, dependency);
157   default:
158     fatal("Bad basic type %s", type2name(bt));
159   }
160   return nullptr;
161 }
162 
163 TypeNode* ConstraintCastNode::dominating_cast(PhaseGVN* gvn, PhaseTransform* pt) const {
164   if (_dependency == UnconditionalDependency) {
165     return nullptr;
166   }
167   Node* val = in(1);
168   Node* ctl = in(0);
169   int opc = Opcode();
170   if (ctl == nullptr) {
171     return nullptr;
172   }
173   // Range check CastIIs may all end up under a single range check and
174   // in that case only the narrower CastII would be kept by the code
175   // below which would be incorrect.
176   if (is_CastII() && as_CastII()->has_range_check()) {
177     return nullptr;
178   }
179   if (type()->isa_rawptr() && (gvn->type_or_null(val) == nullptr || gvn->type(val)->isa_oopptr())) {
180     return nullptr;
181   }
182   for (DUIterator_Fast imax, i = val->fast_outs(imax); i < imax; i++) {
183     Node* u = val->fast_out(i);
184     if (u != this &&
185         u->outcnt() > 0 &&
186         u->Opcode() == opc &&
187         u->in(0) != nullptr &&
188         higher_equal_types(gvn, u)) {
189       if (pt->is_dominator(u->in(0), ctl)) {
190         return u->as_Type();
191       }
192       if (is_CheckCastPP() && u->in(1)->is_Proj() && u->in(1)->in(0)->is_Allocate() &&
193           u->in(0)->is_Proj() && u->in(0)->in(0)->is_Initialize() &&
194           u->in(1)->in(0)->as_Allocate()->initialization() == u->in(0)->in(0)) {
195         // CheckCastPP following an allocation always dominates all
196         // use of the allocation result
197         return u->as_Type();
198       }
199     }
200   }
201   return nullptr;
202 }
203 
204 bool ConstraintCastNode::higher_equal_types(PhaseGVN* phase, const Node* other) const {
205   const Type* t = phase->type(other);
206   if (!t->higher_equal_speculative(type())) {
207     return false;
208   }
209   if (_extra_types != nullptr) {
210     for (uint i = 0; i < _extra_types->cnt(); ++i) {
211       if (!t->higher_equal_speculative(_extra_types->field_at(i))) {
212         return false;
213       }
214     }
215   }
216   return true;
217 }
218 
219 #ifndef PRODUCT
220 void ConstraintCastNode::dump_spec(outputStream *st) const {
221   TypeNode::dump_spec(st);
222   if (_extra_types != nullptr) {
223     st->print(" extra types: ");
224     _extra_types->dump_on(st);
225   }
226   if (_dependency != RegularDependency) {
227     st->print(" %s dependency", _dependency == StrongDependency ? "strong" : "unconditional");
228   }
229 }
230 #endif
231 
232 const Type* CastIINode::Value(PhaseGVN* phase) const {
233   const Type *res = ConstraintCastNode::Value(phase);
234   if (res == Type::TOP) {
235     return Type::TOP;
236   }
237   assert(res->isa_int(), "res must be int");
238 
239   // Similar to ConvI2LNode::Value() for the same reasons
240   // see if we can remove type assertion after loop opts
241   res = widen_type(phase, res, T_INT);
242 
243   return res;
244 }
245 
246 Node* ConstraintCastNode::find_or_make_integer_cast(PhaseIterGVN* igvn, Node* parent, const TypeInteger* type) const {
247   Node* n = clone();
248   n->set_req(1, parent);
249   n->as_ConstraintCast()->set_type(type);
250   Node* existing = igvn->hash_find_insert(n);
251   if (existing != nullptr) {
252     n->destruct(igvn);
253     return existing;
254   }
255   return igvn->register_new_node_with_optimizer(n);
256 }
257 
258 Node *CastIINode::Ideal(PhaseGVN *phase, bool can_reshape) {
259   Node* progress = ConstraintCastNode::Ideal(phase, can_reshape);
260   if (progress != nullptr) {
261     return progress;
262   }
263   if (can_reshape && !phase->C->post_loop_opts_phase()) {
264     // makes sure we run ::Value to potentially remove type assertion after loop opts
265     phase->C->record_for_post_loop_opts_igvn(this);
266   }
267   if (!_range_check_dependency || phase->C->post_loop_opts_phase()) {
268     return optimize_integer_cast(phase, T_INT);
269   }
270   phase->C->record_for_post_loop_opts_igvn(this);
271   return nullptr;
272 }
273 
274 Node* CastIINode::Identity(PhaseGVN* phase) {
275   Node* progress = ConstraintCastNode::Identity(phase);
276   if (progress != this) {
277     return progress;
278   }
279   return this;
280 }
281 
282 bool CastIINode::cmp(const Node &n) const {
283   return ConstraintCastNode::cmp(n) && ((CastIINode&)n)._range_check_dependency == _range_check_dependency;
284 }
285 
286 uint CastIINode::size_of() const {
287   return sizeof(*this);
288 }
289 
290 #ifndef PRODUCT
291 void CastIINode::dump_spec(outputStream* st) const {
292   ConstraintCastNode::dump_spec(st);
293   if (_range_check_dependency) {
294     st->print(" range check dependency");
295   }
296 }
297 #endif
298 
299 CastIINode* CastIINode::pin_array_access_node() const {
300   assert(_dependency == RegularDependency, "already pinned");
301   if (has_range_check()) {
302     return new CastIINode(in(0), in(1), bottom_type(), StrongDependency, has_range_check());
303   }
304   return nullptr;
305 }
306 
307 void CastIINode::remove_range_check_cast(Compile* C) {
308   if (has_range_check()) {
309     // Range check CastII nodes feed into an address computation subgraph. Remove them to let that subgraph float freely.
310     // For memory access or integer divisions nodes that depend on the cast, record the dependency on the cast's control
311     // as a precedence edge, so they can't float above the cast in case that cast's narrowed type helped eliminate a
312     // range check or a null divisor check.
313     assert(in(0) != nullptr, "All RangeCheck CastII must have a control dependency");
314     ResourceMark rm;
315     Unique_Node_List wq;
316     wq.push(this);
317     for (uint next = 0; next < wq.size(); ++next) {
318       Node* m = wq.at(next);
319       for (DUIterator_Fast imax, i = m->fast_outs(imax); i < imax; i++) {
320         Node* use = m->fast_out(i);
321         if (use->is_Mem() || use->is_div_or_mod(T_INT) || use->is_div_or_mod(T_LONG)) {
322           use->ensure_control_or_add_prec(in(0));
323         } else if (!use->is_CFG() && !use->is_Phi()) {
324           wq.push(use);
325         }
326       }
327     }
328     subsume_by(in(1), C);
329     if (outcnt() == 0) {
330       disconnect_inputs(C);
331     }
332   }
333 }
334 
335 
336 const Type* CastLLNode::Value(PhaseGVN* phase) const {
337   const Type* res = ConstraintCastNode::Value(phase);
338   if (res == Type::TOP) {
339     return Type::TOP;
340   }
341   assert(res->isa_long(), "res must be long");
342 
343   return widen_type(phase, res, T_LONG);
344 }
345 
346 bool CastLLNode::is_inner_loop_backedge(ProjNode* proj) {
347   if (proj != nullptr) {
348     Node* ctrl_use = proj->unique_ctrl_out_or_null();
349     if (ctrl_use != nullptr && ctrl_use->Opcode() == Op_Loop &&
350         ctrl_use->in(2) == proj &&
351         ctrl_use->as_Loop()->is_loop_nest_inner_loop()) {
352       return true;
353     }
354   }
355   return false;
356 }
357 
358 bool CastLLNode::cmp_used_at_inner_loop_exit_test(CmpNode* cmp) {
359   for (DUIterator_Fast imax, i = cmp->fast_outs(imax); i < imax; i++) {
360     Node* bol = cmp->fast_out(i);
361     if (bol->Opcode() == Op_Bool) {
362       for (DUIterator_Fast jmax, j = bol->fast_outs(jmax); j < jmax; j++) {
363         Node* iff = bol->fast_out(j);
364         if (iff->Opcode() == Op_If) {
365           ProjNode* true_proj = iff->as_If()->proj_out_or_null(true);
366           ProjNode* false_proj = iff->as_If()->proj_out_or_null(false);
367           if (is_inner_loop_backedge(true_proj) || is_inner_loop_backedge(false_proj)) {
368             return true;
369           }
370         }
371       }
372     }
373   }
374   return false;
375 }
376 
377 // Find if this is a cast node added by PhaseIdealLoop::create_loop_nest() to narrow the number of iterations of the
378 // inner loop
379 bool CastLLNode::used_at_inner_loop_exit_test() const {
380   for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
381     Node* convl2i = fast_out(i);
382     if (convl2i->Opcode() == Op_ConvL2I) {
383       for (DUIterator_Fast jmax, j = convl2i->fast_outs(jmax); j < jmax; j++) {
384         Node* cmp_or_sub = convl2i->fast_out(j);
385         if (cmp_or_sub->Opcode() == Op_CmpI) {
386           if (cmp_used_at_inner_loop_exit_test(cmp_or_sub->as_Cmp())) {
387             // (Loop .. .. (IfProj (If (Bool (CmpI (ConvL2I (CastLL )))))))
388             return true;
389           }
390         } else if (cmp_or_sub->Opcode() == Op_SubI && cmp_or_sub->in(1)->find_int_con(-1) == 0) {
391           for (DUIterator_Fast kmax, k = cmp_or_sub->fast_outs(kmax); k < kmax; k++) {
392             Node* cmp = cmp_or_sub->fast_out(k);
393             if (cmp->Opcode() == Op_CmpI) {
394               if (cmp_used_at_inner_loop_exit_test(cmp->as_Cmp())) {
395                 // (Loop .. .. (IfProj (If (Bool (CmpI (SubI 0 (ConvL2I (CastLL ))))))))
396                 return true;
397               }
398             }
399           }
400         }
401       }
402     }
403   }
404   return false;
405 }
406 
407 Node* CastLLNode::Ideal(PhaseGVN* phase, bool can_reshape) {
408   Node* progress = ConstraintCastNode::Ideal(phase, can_reshape);
409   if (progress != nullptr) {
410     return progress;
411   }
412   if (!phase->C->post_loop_opts_phase()) {
413     // makes sure we run ::Value to potentially remove type assertion after loop opts
414     phase->C->record_for_post_loop_opts_igvn(this);
415   }
416   // transform (CastLL (ConvI2L ..)) into (ConvI2L (CastII ..)) if the type of the CastLL is narrower than the type of
417   // the ConvI2L.
418   Node* in1 = in(1);
419   if (in1 != nullptr && in1->Opcode() == Op_ConvI2L) {
420     const Type* t = Value(phase);
421     const Type* t_in = phase->type(in1);
422     if (t != Type::TOP && t_in != Type::TOP) {
423       const TypeLong* tl = t->is_long();
424       const TypeLong* t_in_l = t_in->is_long();
425       assert(tl->_lo >= t_in_l->_lo && tl->_hi <= t_in_l->_hi, "CastLL type should be narrower than or equal to the type of its input");
426       assert((tl != t_in_l) == (tl->_lo > t_in_l->_lo || tl->_hi < t_in_l->_hi), "if type differs then this nodes's type must be narrower");
427       if (tl != t_in_l) {
428         const TypeInt* ti = TypeInt::make(checked_cast<jint>(tl->_lo), checked_cast<jint>(tl->_hi), tl->_widen);
429         Node* castii = phase->transform(new CastIINode(in(0), in1->in(1), ti));
430         Node* convi2l = in1->clone();
431         convi2l->set_req(1, castii);
432         return convi2l;
433       }
434     }
435   }
436   // If it's a cast created by PhaseIdealLoop::short_running_loop(), don't transform it until the counted loop is created
437   // in next loop opts pass
438   if (!can_reshape || !used_at_inner_loop_exit_test()) {
439     return optimize_integer_cast(phase, T_LONG);
440   }
441   return nullptr;
442 }
443 
444 //=============================================================================
445 //------------------------------Identity---------------------------------------
446 // If input is already higher or equal to cast type, then this is an identity.
447 Node* CheckCastPPNode::Identity(PhaseGVN* phase) {
448   if (in(1)->is_InlineType() && _type->isa_instptr() && phase->type(in(1))->inline_klass()->is_subtype_of(_type->is_instptr()->instance_klass())) {
449     return in(1);
450   }
451   return ConstraintCastNode::Identity(phase);
452 }
453 
454 //------------------------------Value------------------------------------------
455 // Take 'join' of input and cast-up type, unless working with an Interface
456 const Type* CheckCastPPNode::Value(PhaseGVN* phase) const {
457   if( in(0) && phase->type(in(0)) == Type::TOP ) return Type::TOP;
458 
459   const Type *inn = phase->type(in(1));
460   if( inn == Type::TOP ) return Type::TOP;  // No information yet
461 
462   if (inn->isa_oopptr() && _type->isa_oopptr()) {
463     return ConstraintCastNode::Value(phase);
464   }
465 
466   const TypePtr *in_type = inn->isa_ptr();
467   const TypePtr *my_type = _type->isa_ptr();
468   const Type *result = _type;
469   if (in_type != nullptr && my_type != nullptr) {
470     // TODO 8302672
471     if (!StressReflectiveCode && my_type->isa_aryptr() && in_type->isa_aryptr()) {
472       // Propagate array properties (not flat/null-free)
473       // Don't do this when StressReflectiveCode is enabled because it might lead to
474       // a dying data path while the corresponding flat/null-free check is not folded.
475       my_type = my_type->is_aryptr()->update_properties(in_type->is_aryptr());
476       if (my_type == nullptr) {
477         return Type::TOP; // Inconsistent properties
478       }
479     }
480     TypePtr::PTR in_ptr = in_type->ptr();
481     if (in_ptr == TypePtr::Null) {
482       result = in_type;
483     } else if (in_ptr != TypePtr::Constant) {
484       result = my_type->cast_to_ptr_type(my_type->join_ptr(in_ptr));
485     }
486   }
487 
488   return result;
489 }
490 
491 //=============================================================================
492 //------------------------------Value------------------------------------------
493 const Type* CastX2PNode::Value(PhaseGVN* phase) const {
494   const Type* t = phase->type(in(1));
495   if (t == Type::TOP) return Type::TOP;
496   if (t->base() == Type_X && t->singleton()) {
497     uintptr_t bits = (uintptr_t) t->is_intptr_t()->get_con();
498     if (bits == 0)   return TypePtr::NULL_PTR;
499     return TypeRawPtr::make((address) bits);
500   }
501   return CastX2PNode::bottom_type();
502 }
503 
504 //------------------------------Idealize---------------------------------------
505 static inline bool fits_in_int(const Type* t, bool but_not_min_int = false) {
506   if (t == Type::TOP)  return false;
507   const TypeX* tl = t->is_intptr_t();
508   jint lo = min_jint;
509   jint hi = max_jint;
510   if (but_not_min_int)  ++lo;  // caller wants to negate the value w/o overflow
511   return (tl->_lo >= lo) && (tl->_hi <= hi);
512 }
513 
514 static inline Node* addP_of_X2P(PhaseGVN *phase,
515                                 Node* base,
516                                 Node* dispX,
517                                 bool negate = false) {
518   if (negate) {
519     dispX = phase->transform(new SubXNode(phase->MakeConX(0), dispX));
520   }
521   return new AddPNode(phase->C->top(),
522                       phase->transform(new CastX2PNode(base)),
523                       dispX);
524 }
525 
526 Node *CastX2PNode::Ideal(PhaseGVN *phase, bool can_reshape) {
527   // convert CastX2P(AddX(x, y)) to AddP(CastX2P(x), y) if y fits in an int
528   int op = in(1)->Opcode();
529   Node* x;
530   Node* y;
531   switch (op) {
532     case Op_SubX:
533     x = in(1)->in(1);
534     // Avoid ideal transformations ping-pong between this and AddP for raw pointers.
535     if (phase->find_intptr_t_con(x, -1) == 0)
536     break;
537     y = in(1)->in(2);
538     if (fits_in_int(phase->type(y), true)) {
539       return addP_of_X2P(phase, x, y, true);
540     }
541     break;
542     case Op_AddX:
543     x = in(1)->in(1);
544     y = in(1)->in(2);
545     if (fits_in_int(phase->type(y))) {
546       return addP_of_X2P(phase, x, y);
547     }
548     if (fits_in_int(phase->type(x))) {
549       return addP_of_X2P(phase, y, x);
550     }
551     break;
552   }
553   return nullptr;
554 }
555 
556 //------------------------------Identity---------------------------------------
557 Node* CastX2PNode::Identity(PhaseGVN* phase) {
558   if (in(1)->Opcode() == Op_CastP2X)  return in(1)->in(1);
559   return this;
560 }
561 
562 //=============================================================================
563 //------------------------------Value------------------------------------------
564 const Type* CastP2XNode::Value(PhaseGVN* phase) const {
565   const Type* t = phase->type(in(1));
566   if (t == Type::TOP) return Type::TOP;
567   if (t->base() == Type::RawPtr && t->singleton()) {
568     uintptr_t bits = (uintptr_t) t->is_rawptr()->get_con();
569     return TypeX::make(bits);
570   }
571 
572   if (t->is_zero_type() || !t->maybe_null()) {
573     for (DUIterator_Fast imax, i = fast_outs(imax); i < imax; i++) {
574       Node* u = fast_out(i);
575       if (u->Opcode() == Op_OrL) {
576         for (DUIterator_Fast jmax, j = u->fast_outs(jmax); j < jmax; j++) {
577           Node* cmp = u->fast_out(j);
578           if (cmp->Opcode() == Op_CmpL) {
579             // Give CmpL a chance to get optimized
580             phase->record_for_igvn(cmp);
581           }
582         }
583       }
584     }
585   }
586 
587   return CastP2XNode::bottom_type();
588 }
589 
590 Node *CastP2XNode::Ideal(PhaseGVN *phase, bool can_reshape) {
591   return (in(0) && remove_dead_region(phase, can_reshape)) ? this : nullptr;
592 }
593 
594 //------------------------------Identity---------------------------------------
595 Node* CastP2XNode::Identity(PhaseGVN* phase) {
596   if (in(1)->Opcode() == Op_CastX2P)  return in(1)->in(1);
597   return this;
598 }
599 
600 Node* ConstraintCastNode::make_cast_for_type(Node* c, Node* in, const Type* type, DependencyType dependency,
601                                              const TypeTuple* types) {
602   if (type->isa_int()) {
603     return new CastIINode(c, in, type, dependency, false, types);
604   } else if (type->isa_long()) {
605     return new CastLLNode(c, in, type, dependency, types);
606   } else if (type->isa_half_float()) {
607     return new CastHHNode(c, in, type, dependency, types);
608   } else if (type->isa_float()) {
609     return new CastFFNode(c, in, type, dependency, types);
610   } else if (type->isa_double()) {
611     return new CastDDNode(c, in, type, dependency, types);
612   } else if (type->isa_vect()) {
613     return new CastVVNode(c, in, type, dependency, types);
614   } else if (type->isa_ptr()) {
615     return new CastPPNode(c, in, type, dependency, types);
616   }
617   fatal("unreachable. Invalid cast type.");
618   return nullptr;
619 }
620 
621 Node* ConstraintCastNode::optimize_integer_cast(PhaseGVN* phase, BasicType bt) {
622   PhaseIterGVN *igvn = phase->is_IterGVN();
623   const TypeInteger* this_type = this->type()->isa_integer(bt);
624   if (this_type == nullptr) {
625     return nullptr;
626   }
627 
628   Node* z = in(1);
629   const TypeInteger* rx = nullptr;
630   const TypeInteger* ry = nullptr;
631   // Similar to ConvI2LNode::Ideal() for the same reasons
632   if (Compile::push_thru_add(phase, z, this_type, rx, ry, bt, bt)) {
633     if (igvn == nullptr) {
634       // Postpone this optimization to iterative GVN, where we can handle deep
635       // AddI chains without an exponential number of recursive Ideal() calls.
636       phase->record_for_igvn(this);
637       return nullptr;
638     }
639     int op = z->Opcode();
640     Node* x = z->in(1);
641     Node* y = z->in(2);
642 
643     Node* cx = find_or_make_integer_cast(igvn, x, rx);
644     Node* cy = find_or_make_integer_cast(igvn, y, ry);
645     if (op == Op_Add(bt)) {
646       return AddNode::make(cx, cy, bt);
647     } else {
648       assert(op == Op_Sub(bt), "");
649       return SubNode::make(cx, cy, bt);
650     }
651     return nullptr;
652   }
653   return nullptr;
654 }
655 
656 const Type* ConstraintCastNode::widen_type(const PhaseGVN* phase, const Type* res, BasicType bt) const {
657   if (!phase->C->post_loop_opts_phase()) {
658     return res;
659   }
660 
661   // At VerifyConstraintCasts == 1, we verify the ConstraintCastNodes that are present during code
662   // emission. This allows us detecting possible mis-scheduling due to these nodes being pinned at
663   // the wrong control nodes.
664   // At VerifyConstraintCasts == 2, we do not perform widening so that we can verify the
665   // correctness of more ConstraintCastNodes. This further helps us detect possible
666   // mis-transformations that may happen due to these nodes being pinned at the wrong control
667   // nodes.
668   if (VerifyConstraintCasts > 1) {
669     return res;
670   }
671 
672   const TypeInteger* this_type = res->is_integer(bt);
673   const TypeInteger* in_type = phase->type(in(1))->isa_integer(bt);
674   if (in_type != nullptr &&
675       (in_type->lo_as_long() != this_type->lo_as_long() ||
676        in_type->hi_as_long() != this_type->hi_as_long())) {
677     jlong lo1 = this_type->lo_as_long();
678     jlong hi1 = this_type->hi_as_long();
679     int w1 = this_type->_widen;
680     if (lo1 >= 0) {
681       // Keep a range assertion of >=0.
682       lo1 = 0;        hi1 = max_signed_integer(bt);
683     } else if (hi1 < 0) {
684       // Keep a range assertion of <0.
685       lo1 = min_signed_integer(bt); hi1 = -1;
686     } else {
687       lo1 = min_signed_integer(bt); hi1 = max_signed_integer(bt);
688     }
689     return TypeInteger::make(MAX2(in_type->lo_as_long(), lo1),
690                              MIN2(in_type->hi_as_long(), hi1),
691                              MAX2((int)in_type->_widen, w1), bt);
692   }
693   return res;
694 }