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src/hotspot/share/opto/castnode.cpp

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 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 "opto/addnode.hpp"
 26 #include "opto/callnode.hpp"
 27 #include "opto/castnode.hpp"
 28 #include "opto/cfgnode.hpp"
 29 #include "opto/connode.hpp"


 30 #include "opto/loopnode.hpp"
 31 #include "opto/matcher.hpp"
 32 #include "opto/phaseX.hpp"

 33 #include "opto/subnode.hpp"
 34 #include "opto/type.hpp"
 35 #include "utilities/checkedCast.hpp"
 36 
 37 const ConstraintCastNode::DependencyType ConstraintCastNode::DependencyType::FloatingNarrowing(true, true, "floating narrowing dependency"); // not pinned, narrows type
 38 const ConstraintCastNode::DependencyType ConstraintCastNode::DependencyType::FloatingNonNarrowing(true, false, "floating non-narrowing dependency"); // not pinned, doesn't narrow type
 39 const ConstraintCastNode::DependencyType ConstraintCastNode::DependencyType::NonFloatingNarrowing(false, true, "non-floating narrowing dependency"); // pinned, narrows type
 40 const ConstraintCastNode::DependencyType ConstraintCastNode::DependencyType::NonFloatingNonNarrowing(false, false, "non-floating non-narrowing dependency"); // pinned, doesn't narrow type
 41 
 42 //=============================================================================
 43 // If input is already higher or equal to cast type, then this is an identity.
 44 Node* ConstraintCastNode::Identity(PhaseGVN* phase) {
 45   if (!_dependency.narrows_type()) {
 46     // If this cast doesn't carry a type dependency (i.e. not used for type narrowing), we cannot optimize it.
 47     return this;
 48   }
 49 
 50   // This cast node carries a type dependency. We can remove it if:
 51   // - Its input has a narrower type
 52   // - There's a dominating cast with same input but narrower type

 90       if (rt->empty()) {
 91         assert(ft == Type::TOP, "special case #2");
 92       }
 93       break;
 94     }
 95     case Op_CastPP:
 96     if (in_type == TypePtr::NULL_PTR &&
 97         _type->isa_ptr() && _type->is_ptr()->_ptr == TypePtr::NotNull) {
 98       assert(ft == Type::TOP, "special case #3");
 99       break;
100     }
101   }
102 #endif //ASSERT
103 
104   return ft;
105 }
106 
107 //------------------------------Ideal------------------------------------------
108 // Return a node which is more "ideal" than the current node.  Strip out
109 // control copies
110 Node* ConstraintCastNode::Ideal(PhaseGVN* phase, bool can_reshape) {
111   if (in(0) != nullptr && remove_dead_region(phase, can_reshape)) {
112     return this;
113   }














114   if (in(1) != nullptr && phase->type(in(1)) != Type::TOP) {
115     return TypeNode::Ideal(phase, can_reshape);
116   }

117   return nullptr;
118 }
119 
120 uint ConstraintCastNode::hash() const {
121   return TypeNode::hash() + _dependency.hash() + (_extra_types != nullptr ? _extra_types->hash() : 0);
122 }
123 
124 bool ConstraintCastNode::cmp(const Node &n) const {
125   if (!TypeNode::cmp(n)) {
126     return false;
127   }
128   ConstraintCastNode& cast = (ConstraintCastNode&) n;
129   if (!cast._dependency.cmp(_dependency)) {
130     return false;
131   }
132   if (_extra_types == nullptr || cast._extra_types == nullptr) {
133     return _extra_types == cast._extra_types;
134   }
135   return _extra_types->eq(cast._extra_types);
136 }

396       const TypeLong* t_in_l = t_in->is_long();
397       assert(t_in_l->contains(tl), "CastLL type should be narrower than or equal to the type of its input");
398       assert((tl != t_in_l) == t_in_l->strictly_contains(tl), "if type differs then this nodes's type must be narrower");
399       if (tl != t_in_l) {
400         const TypeInt* ti = TypeInt::make(checked_cast<jint>(tl->_lo), checked_cast<jint>(tl->_hi), tl->_widen);
401         Node* castii = phase->transform(new CastIINode(in(0), in1->in(1), ti));
402         Node* convi2l = in1->clone();
403         convi2l->set_req(1, castii);
404         return convi2l;
405       }
406     }
407   }
408   // If it's a cast created by PhaseIdealLoop::short_running_loop(), don't transform it until the counted loop is created
409   // in next loop opts pass
410   if (!can_reshape || !used_at_inner_loop_exit_test()) {
411     return optimize_integer_cast(phase, T_LONG);
412   }
413   return nullptr;
414 }
415 










416 // CastPPNodes are removed before matching, while alias classes are needed in global code motion.
417 // As a result, it is not valid for a CastPPNode to change the oop such that the derived pointers
418 // lie in different alias classes with and without the node. For example, a CastPPNode c may not
419 // cast an Object to a Bottom[], because later removal of c would affect the alias class of c's
420 // array length field (c + arrayOopDesc::length_offset_in_bytes()).
421 //
422 // This function verifies that a CastPPNode on an oop does not violate the aforementioned property.
423 //
424 // TODO 8382147: Currently, this verification only applies during the construction of a CastPPNode,
425 // we may want to apply the same verification during IGVN transformations, as well as final graph
426 // reshaping.
427 void CastPPNode::verify_type(const Type* in_type, const Type* out_type) {
428 #ifdef ASSERT
429   out_type = out_type->join(in_type);
430   if (in_type->empty() || out_type->empty()) {
431     return;
432   }
433   if (in_type == TypePtr::NULL_PTR || out_type == TypePtr::NULL_PTR) {
434     return;
435   }

449   assert(in_type->is_instptr()->instance_klass() == out_type->is_instptr()->instance_klass(), "must not cast to a different type");
450 #endif // ASSERT
451 }
452 
453 //------------------------------Value------------------------------------------
454 // Take 'join' of input and cast-up type, unless working with an Interface
455 const Type* CheckCastPPNode::Value(PhaseGVN* phase) const {
456   if( in(0) && phase->type(in(0)) == Type::TOP ) return Type::TOP;
457 
458   const Type *inn = phase->type(in(1));
459   if( inn == Type::TOP ) return Type::TOP;  // No information yet
460 
461   if (inn->isa_oopptr() && _type->isa_oopptr()) {
462     return ConstraintCastNode::Value(phase);
463   }
464 
465   const TypePtr *in_type = inn->isa_ptr();
466   const TypePtr *my_type = _type->isa_ptr();
467   const Type *result = _type;
468   if (in_type != nullptr && my_type != nullptr) {










469     TypePtr::PTR in_ptr = in_type->ptr();
470     if (in_ptr == TypePtr::Null) {
471       result = in_type;
472     } else if (in_ptr != TypePtr::Constant) {
473       result =  my_type->cast_to_ptr_type(my_type->join_ptr(in_ptr));
474     }
475   }
476 
477   return result;
478 }
479 
480 Node* CheckCastPPNode::pin_node_under_control_impl() const {
481   assert(_dependency.is_floating(), "already pinned");
482   return new CheckCastPPNode(in(0), in(1), bottom_type(), _dependency.with_pinned_dependency(), _extra_types);
483 }
484 
485 //=============================================================================
486 //------------------------------Value------------------------------------------
487 const Type* CastX2PNode::Value(PhaseGVN* phase) const {
488   const Type* t = phase->type(in(1));
489   if (t == Type::TOP) return Type::TOP;
490   if (t->base() == Type_X && t->singleton()) {
491     uintptr_t bits = (uintptr_t) t->is_intptr_t()->get_con();
492     if (bits == 0)   return TypePtr::NULL_PTR;
493     return TypeRawPtr::make((address) bits);

 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 "opto/addnode.hpp"
 26 #include "opto/callnode.hpp"
 27 #include "opto/castnode.hpp"
 28 #include "opto/cfgnode.hpp"
 29 #include "opto/connode.hpp"
 30 #include "opto/graphKit.hpp"
 31 #include "opto/inlinetypenode.hpp"
 32 #include "opto/loopnode.hpp"
 33 #include "opto/matcher.hpp"
 34 #include "opto/phaseX.hpp"
 35 #include "opto/rootnode.hpp"
 36 #include "opto/subnode.hpp"
 37 #include "opto/type.hpp"
 38 #include "utilities/checkedCast.hpp"
 39 
 40 const ConstraintCastNode::DependencyType ConstraintCastNode::DependencyType::FloatingNarrowing(true, true, "floating narrowing dependency"); // not pinned, narrows type
 41 const ConstraintCastNode::DependencyType ConstraintCastNode::DependencyType::FloatingNonNarrowing(true, false, "floating non-narrowing dependency"); // not pinned, doesn't narrow type
 42 const ConstraintCastNode::DependencyType ConstraintCastNode::DependencyType::NonFloatingNarrowing(false, true, "non-floating narrowing dependency"); // pinned, narrows type
 43 const ConstraintCastNode::DependencyType ConstraintCastNode::DependencyType::NonFloatingNonNarrowing(false, false, "non-floating non-narrowing dependency"); // pinned, doesn't narrow type
 44 
 45 //=============================================================================
 46 // If input is already higher or equal to cast type, then this is an identity.
 47 Node* ConstraintCastNode::Identity(PhaseGVN* phase) {
 48   if (!_dependency.narrows_type()) {
 49     // If this cast doesn't carry a type dependency (i.e. not used for type narrowing), we cannot optimize it.
 50     return this;
 51   }
 52 
 53   // This cast node carries a type dependency. We can remove it if:
 54   // - Its input has a narrower type
 55   // - There's a dominating cast with same input but narrower type

 93       if (rt->empty()) {
 94         assert(ft == Type::TOP, "special case #2");
 95       }
 96       break;
 97     }
 98     case Op_CastPP:
 99     if (in_type == TypePtr::NULL_PTR &&
100         _type->isa_ptr() && _type->is_ptr()->_ptr == TypePtr::NotNull) {
101       assert(ft == Type::TOP, "special case #3");
102       break;
103     }
104   }
105 #endif //ASSERT
106 
107   return ft;
108 }
109 
110 //------------------------------Ideal------------------------------------------
111 // Return a node which is more "ideal" than the current node.  Strip out
112 // control copies
113 Node *ConstraintCastNode::Ideal(PhaseGVN *phase, bool can_reshape) {
114   if (in(0) != nullptr && remove_dead_region(phase, can_reshape)) {
115     return this;
116   }
117 
118   // Push cast through InlineTypeNode
119   InlineTypeNode* vt = in(1)->isa_InlineType();
120   if (vt != nullptr && phase->type(vt)->filter_speculative(_type) != Type::TOP) {
121     Node* cast = clone();
122     cast->set_req(1, vt->get_oop());
123     vt = vt->clone()->as_InlineType();
124     if (!_type->maybe_null()) {
125       vt->as_InlineType()->set_null_marker(*phase);
126     }
127     vt->set_oop(*phase, phase->transform(cast));
128     return vt;
129   }
130 
131   if (in(1) != nullptr && phase->type(in(1)) != Type::TOP) {
132     return TypeNode::Ideal(phase, can_reshape);
133   }
134 
135   return nullptr;
136 }
137 
138 uint ConstraintCastNode::hash() const {
139   return TypeNode::hash() + _dependency.hash() + (_extra_types != nullptr ? _extra_types->hash() : 0);
140 }
141 
142 bool ConstraintCastNode::cmp(const Node &n) const {
143   if (!TypeNode::cmp(n)) {
144     return false;
145   }
146   ConstraintCastNode& cast = (ConstraintCastNode&) n;
147   if (!cast._dependency.cmp(_dependency)) {
148     return false;
149   }
150   if (_extra_types == nullptr || cast._extra_types == nullptr) {
151     return _extra_types == cast._extra_types;
152   }
153   return _extra_types->eq(cast._extra_types);
154 }

414       const TypeLong* t_in_l = t_in->is_long();
415       assert(t_in_l->contains(tl), "CastLL type should be narrower than or equal to the type of its input");
416       assert((tl != t_in_l) == t_in_l->strictly_contains(tl), "if type differs then this nodes's type must be narrower");
417       if (tl != t_in_l) {
418         const TypeInt* ti = TypeInt::make(checked_cast<jint>(tl->_lo), checked_cast<jint>(tl->_hi), tl->_widen);
419         Node* castii = phase->transform(new CastIINode(in(0), in1->in(1), ti));
420         Node* convi2l = in1->clone();
421         convi2l->set_req(1, castii);
422         return convi2l;
423       }
424     }
425   }
426   // If it's a cast created by PhaseIdealLoop::short_running_loop(), don't transform it until the counted loop is created
427   // in next loop opts pass
428   if (!can_reshape || !used_at_inner_loop_exit_test()) {
429     return optimize_integer_cast(phase, T_LONG);
430   }
431   return nullptr;
432 }
433 
434 //=============================================================================
435 //------------------------------Identity---------------------------------------
436 // If input is already higher or equal to cast type, then this is an identity.
437 Node* CheckCastPPNode::Identity(PhaseGVN* phase) {
438   if (in(1)->is_InlineType() && _type->isa_instptr() && phase->type(in(1))->inline_klass()->is_subtype_of(_type->is_instptr()->instance_klass())) {
439     return in(1);
440   }
441   return ConstraintCastNode::Identity(phase);
442 }
443 
444 // CastPPNodes are removed before matching, while alias classes are needed in global code motion.
445 // As a result, it is not valid for a CastPPNode to change the oop such that the derived pointers
446 // lie in different alias classes with and without the node. For example, a CastPPNode c may not
447 // cast an Object to a Bottom[], because later removal of c would affect the alias class of c's
448 // array length field (c + arrayOopDesc::length_offset_in_bytes()).
449 //
450 // This function verifies that a CastPPNode on an oop does not violate the aforementioned property.
451 //
452 // TODO 8382147: Currently, this verification only applies during the construction of a CastPPNode,
453 // we may want to apply the same verification during IGVN transformations, as well as final graph
454 // reshaping.
455 void CastPPNode::verify_type(const Type* in_type, const Type* out_type) {
456 #ifdef ASSERT
457   out_type = out_type->join(in_type);
458   if (in_type->empty() || out_type->empty()) {
459     return;
460   }
461   if (in_type == TypePtr::NULL_PTR || out_type == TypePtr::NULL_PTR) {
462     return;
463   }

477   assert(in_type->is_instptr()->instance_klass() == out_type->is_instptr()->instance_klass(), "must not cast to a different type");
478 #endif // ASSERT
479 }
480 
481 //------------------------------Value------------------------------------------
482 // Take 'join' of input and cast-up type, unless working with an Interface
483 const Type* CheckCastPPNode::Value(PhaseGVN* phase) const {
484   if( in(0) && phase->type(in(0)) == Type::TOP ) return Type::TOP;
485 
486   const Type *inn = phase->type(in(1));
487   if( inn == Type::TOP ) return Type::TOP;  // No information yet
488 
489   if (inn->isa_oopptr() && _type->isa_oopptr()) {
490     return ConstraintCastNode::Value(phase);
491   }
492 
493   const TypePtr *in_type = inn->isa_ptr();
494   const TypePtr *my_type = _type->isa_ptr();
495   const Type *result = _type;
496   if (in_type != nullptr && my_type != nullptr) {
497     // TODO 8302672
498     if (!StressReflectiveCode && my_type->isa_aryptr() && in_type->isa_aryptr()) {
499       // Propagate array properties (not flat/null-free)
500       // Don't do this when StressReflectiveCode is enabled because it might lead to
501       // a dying data path while the corresponding flat/null-free check is not folded.
502       my_type = my_type->is_aryptr()->update_properties(in_type->is_aryptr());
503       if (my_type == nullptr) {
504         return Type::TOP; // Inconsistent properties
505       }
506     }
507     TypePtr::PTR in_ptr = in_type->ptr();
508     if (in_ptr == TypePtr::Null) {
509       result = in_type;
510     } else if (in_ptr != TypePtr::Constant) {
511       result = my_type->cast_to_ptr_type(my_type->join_ptr(in_ptr));
512     }
513   }
514 
515   return result;
516 }
517 
518 Node* CheckCastPPNode::pin_node_under_control_impl() const {
519   assert(_dependency.is_floating(), "already pinned");
520   return new CheckCastPPNode(in(0), in(1), bottom_type(), _dependency.with_pinned_dependency(), _extra_types);
521 }
522 
523 //=============================================================================
524 //------------------------------Value------------------------------------------
525 const Type* CastX2PNode::Value(PhaseGVN* phase) const {
526   const Type* t = phase->type(in(1));
527   if (t == Type::TOP) return Type::TOP;
528   if (t->base() == Type_X && t->singleton()) {
529     uintptr_t bits = (uintptr_t) t->is_intptr_t()->get_con();
530     if (bits == 0)   return TypePtr::NULL_PTR;
531     return TypeRawPtr::make((address) bits);
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