6723160: Nightly failure: Error: meet not symmetric

Summary: Add missing _instance_id settings and other EA fixes.
Reviewed-by: rasbold

hotspot/src/share/vm/adlc/formssel.cpp

@@ -3825,6 +3825,8 @@ int MatchRule::is_expensive() const {
         strcmp(opType,"ConvL2D")==0 ||
         strcmp(opType,"ConvL2F")==0 ||
         strcmp(opType,"ConvL2I")==0 ||
+        strcmp(opType,"DecodeN")==0 ||
+        strcmp(opType,"EncodeP")==0 ||
         strcmp(opType,"RoundDouble")==0 ||
         strcmp(opType,"RoundFloat")==0 ||
         strcmp(opType,"ReverseBytesI")==0 ||

hotspot/src/share/vm/opto/callnode.cpp

@@ -631,61 +631,13 @@ uint CallNode::match_edge(uint idx) const {
 bool CallNode::may_modify(const TypePtr *addr_t, PhaseTransform *phase) {
   const TypeOopPtr *adrInst_t  = addr_t->isa_oopptr();
 
-  // if not an InstPtr or not an instance type, assume the worst
-  if (adrInst_t == NULL || !adrInst_t->is_known_instance_field()) {
+  // If not an OopPtr or not an instance type, assume the worst.
+  // Note: currently this method is called only for instance types.
+  if (adrInst_t == NULL || !adrInst_t->is_known_instance()) {
     return true;
   }
-  Compile *C = phase->C;
-  int offset = adrInst_t->offset();
-  assert(adrInst_t->klass_is_exact() && offset >= 0, "should be valid offset");
-  ciKlass* adr_k = adrInst_t->klass();
-  assert(adr_k->is_loaded() &&
-         adr_k->is_java_klass() &&
-         !adr_k->is_interface(),
-         "only non-abstract classes are expected");
-
-  int base_idx = C->get_alias_index(adrInst_t);
-  int size = BytesPerLong; // If we don't know the size, assume largest.
-  if (adrInst_t->isa_instptr()) {
-    ciField* field = C->alias_type(base_idx)->field();
-    if (field != NULL) {
-      size = field->size_in_bytes();
-    }
-  } else {
-    assert(adrInst_t->isa_aryptr(), "only arrays are expected");
-    size = type2aelembytes(adr_k->as_array_klass()->element_type()->basic_type());
-  }
-
-  ciMethod * meth = is_CallStaticJava() ?  as_CallStaticJava()->method() : NULL;
-  BCEscapeAnalyzer *bcea = (meth != NULL) ? meth->get_bcea() : NULL;
-
-  const TypeTuple * d = tf()->domain();
-  for (uint i = TypeFunc::Parms; i < d->cnt(); i++) {
-    const Type* t = d->field_at(i);
-    Node *arg = in(i);
-    const Type *at = phase->type(arg);
-    if (at == TypePtr::NULL_PTR || at == Type::TOP)
-      continue;  // null can't affect anything
-
-    const TypeOopPtr *at_ptr = at->isa_oopptr();
-    if (!arg->is_top() && (t->isa_oopptr() != NULL ||
-                           t->isa_ptr() && at_ptr != NULL)) {
-      assert(at_ptr != NULL, "expecting an OopPtr");
-      ciKlass* at_k = at_ptr->klass();
-      if ((adrInst_t->base() == at_ptr->base()) &&
-          at_k->is_loaded() &&
-          at_k->is_java_klass()) {
-        // If we have found an argument matching addr_t, check if the field
-        // at the specified offset is modified.
-        if ((at_k->is_interface() || adr_k == at_k ||
-             adr_k->is_subclass_of(at_k) && !at_ptr->klass_is_exact()) &&
-            (bcea == NULL ||
-             bcea->is_arg_modified(i - TypeFunc::Parms, offset, size))) {
-          return true;
-        }
-      }
-    }
-  }
+  // The instance_id is set only for scalar-replaceable allocations which
+  // are not passed as arguments according to Escape Analysis.
   return false;
 }
 

hotspot/src/share/vm/opto/cfgnode.cpp

@@ -713,7 +713,9 @@ PhiNode* PhiNode::split_out_instance(const TypePtr* at, PhaseIterGVN *igvn) cons
   assert(type() == Type::MEMORY &&
          (t == TypePtr::BOTTOM || t == TypeRawPtr::BOTTOM ||
           t->isa_oopptr() && !t->is_oopptr()->is_known_instance() &&
-          t->is_oopptr()->cast_to_instance_id(t_oop->instance_id()) == t_oop),
+          t->is_oopptr()->cast_to_exactness(true)
+           ->is_oopptr()->cast_to_ptr_type(t_oop->ptr())
+           ->is_oopptr()->cast_to_instance_id(t_oop->instance_id()) == t_oop),
          "bottom or raw memory required");
 
   // Check if an appropriate node already exists.
@@ -1089,6 +1091,8 @@ Node* PhiNode::unique_input(PhaseTransform* phase) {
     if (rc == NULL || phase->type(rc) == Type::TOP)
       continue;                 // ignore unreachable control path
     Node* n = in(i);
+    if (n == NULL)
+      continue;
     Node* un = n->uncast();
     if (un == NULL || un == this || phase->type(un) == Type::TOP) {
       continue; // ignore if top, or in(i) and "this" are in a data cycle

hotspot/src/share/vm/opto/compile.cpp

@@ -999,9 +999,14 @@ const TypePtr *Compile::flatten_alias_type( const TypePtr *tj ) const {
   int offset = tj->offset();
   TypePtr::PTR ptr = tj->ptr();
 
+  // Known instance (scalarizable allocation) alias only with itself.
+  bool is_known_inst = tj->isa_oopptr() != NULL &&
+                       tj->is_oopptr()->is_known_instance();
+
   // Process weird unsafe references.
   if (offset == Type::OffsetBot && (tj->isa_instptr() /*|| tj->isa_klassptr()*/)) {
     assert(InlineUnsafeOps, "indeterminate pointers come only from unsafe ops");
+    assert(!is_known_inst, "scalarizable allocation should not have unsafe references");
     tj = TypeOopPtr::BOTTOM;
     ptr = tj->ptr();
     offset = tj->offset();
@@ -1009,14 +1014,20 @@ const TypePtr *Compile::flatten_alias_type( const TypePtr *tj ) const {
 
   // Array pointers need some flattening
   const TypeAryPtr *ta = tj->isa_aryptr();
-  if( ta && _AliasLevel >= 2 ) {
+  if( ta && is_known_inst ) {
+    if ( offset != Type::OffsetBot &&
+         offset > arrayOopDesc::length_offset_in_bytes() ) {
+      offset = Type::OffsetBot; // Flatten constant access into array body only
+      tj = ta = TypeAryPtr::make(ptr, ta->ary(), ta->klass(), true, offset, ta->instance_id());
+    }
+  } else if( ta && _AliasLevel >= 2 ) {
     // For arrays indexed by constant indices, we flatten the alias
     // space to include all of the array body.  Only the header, klass
     // and array length can be accessed un-aliased.
     if( offset != Type::OffsetBot ) {
       if( ta->const_oop() ) { // methodDataOop or methodOop
         offset = Type::OffsetBot;   // Flatten constant access into array body
-        tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),ta->ary(),ta->klass(),false,Type::OffsetBot, ta->instance_id());
+        tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),ta->ary(),ta->klass(),false,offset);
       } else if( offset == arrayOopDesc::length_offset_in_bytes() ) {
         // range is OK as-is.
         tj = ta = TypeAryPtr::RANGE;
@@ -1030,29 +1041,29 @@ const TypePtr *Compile::flatten_alias_type( const TypePtr *tj ) const {
         ptr = TypePtr::BotPTR;
       } else {                  // Random constant offset into array body
         offset = Type::OffsetBot;   // Flatten constant access into array body
-        tj = ta = TypeAryPtr::make(ptr,ta->ary(),ta->klass(),false,Type::OffsetBot, ta->instance_id());
+        tj = ta = TypeAryPtr::make(ptr,ta->ary(),ta->klass(),false,offset);
       }
     }
     // Arrays of fixed size alias with arrays of unknown size.
     if (ta->size() != TypeInt::POS) {
       const TypeAry *tary = TypeAry::make(ta->elem(), TypeInt::POS);
-      tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,ta->klass(),false,offset, ta->instance_id());
+      tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,ta->klass(),false,offset);
     }
     // Arrays of known objects become arrays of unknown objects.
     if (ta->elem()->isa_narrowoop() && ta->elem() != TypeNarrowOop::BOTTOM) {
       const TypeAry *tary = TypeAry::make(TypeNarrowOop::BOTTOM, ta->size());
-      tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset, ta->instance_id());
+      tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
     }
     if (ta->elem()->isa_oopptr() && ta->elem() != TypeInstPtr::BOTTOM) {
       const TypeAry *tary = TypeAry::make(TypeInstPtr::BOTTOM, ta->size());
-      tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset, ta->instance_id());
+      tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,NULL,false,offset);
     }
     // Arrays of bytes and of booleans both use 'bastore' and 'baload' so
     // cannot be distinguished by bytecode alone.
     if (ta->elem() == TypeInt::BOOL) {
       const TypeAry *tary = TypeAry::make(TypeInt::BYTE, ta->size());
       ciKlass* aklass = ciTypeArrayKlass::make(T_BYTE);
-      tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,aklass,false,offset, ta->instance_id());
+      tj = ta = TypeAryPtr::make(ptr,ta->const_oop(),tary,aklass,false,offset);
     }
     // During the 2nd round of IterGVN, NotNull castings are removed.
     // Make sure the Bottom and NotNull variants alias the same.
@@ -1072,21 +1083,24 @@ const TypePtr *Compile::flatten_alias_type( const TypePtr *tj ) const {
     if( ptr == TypePtr::Constant ) {
       // No constant oop pointers (such as Strings); they alias with
       // unknown strings.
+      assert(!is_known_inst, "not scalarizable allocation");
       tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
-    } else if( to->is_known_instance_field() ) {
+    } else if( is_known_inst ) {
       tj = to; // Keep NotNull and klass_is_exact for instance type
     } else if( ptr == TypePtr::NotNull || to->klass_is_exact() ) {
       // During the 2nd round of IterGVN, NotNull castings are removed.
       // Make sure the Bottom and NotNull variants alias the same.
       // Also, make sure exact and non-exact variants alias the same.
-      tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset, to->instance_id());
+      tj = to = TypeInstPtr::make(TypePtr::BotPTR,to->klass(),false,0,offset);
     }
     // Canonicalize the holder of this field
     ciInstanceKlass *k = to->klass()->as_instance_klass();
     if (offset >= 0 && offset < instanceOopDesc::base_offset_in_bytes()) {
       // First handle header references such as a LoadKlassNode, even if the
       // object's klass is unloaded at compile time (4965979).
-      tj = to = TypeInstPtr::make(TypePtr::BotPTR, env()->Object_klass(), false, NULL, offset, to->instance_id());
+      if (!is_known_inst) { // Do it only for non-instance types
+        tj = to = TypeInstPtr::make(TypePtr::BotPTR, env()->Object_klass(), false, NULL, offset);
+      }
     } else if (offset < 0 || offset >= k->size_helper() * wordSize) {
       to = NULL;
       tj = TypeOopPtr::BOTTOM;
@@ -1094,7 +1108,11 @@ const TypePtr *Compile::flatten_alias_type( const TypePtr *tj ) const {
     } else {
       ciInstanceKlass *canonical_holder = k->get_canonical_holder(offset);
       if (!k->equals(canonical_holder) || tj->offset() != offset) {
-        tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, false, NULL, offset, to->instance_id());
+        if( is_known_inst ) {
+          tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, true, NULL, offset, to->instance_id());
+        } else {
+          tj = to = TypeInstPtr::make(to->ptr(), canonical_holder, false, NULL, offset);
+        }
       }
     }
   }
@@ -1280,7 +1298,9 @@ Compile::AliasType* Compile::find_alias_type(const TypePtr* adr_type, bool no_cr
   assert(flat != TypePtr::BOTTOM,     "cannot alias-analyze an untyped ptr");
   if (flat->isa_oopptr() && !flat->isa_klassptr()) {
     const TypeOopPtr* foop = flat->is_oopptr();
-    const TypePtr* xoop = foop->cast_to_exactness(!foop->klass_is_exact())->is_ptr();
+    // Scalarizable allocations have exact klass always.
+    bool exact = !foop->klass_is_exact() || foop->is_known_instance();
+    const TypePtr* xoop = foop->cast_to_exactness(exact)->is_ptr();
     assert(foop == flatten_alias_type(xoop), "exactness must not affect alias type");
   }
   assert(flat == flatten_alias_type(flat), "exact bit doesn't matter");

hotspot/src/share/vm/opto/escape.cpp

@@ -717,12 +717,17 @@ Node* ConnectionGraph::find_inst_mem(Node *orig_mem, int alias_idx, GrowableArra
       }
     }
   }
-  if (is_instance && result->is_Phi()) {
+  if (result->is_Phi()) {
     PhiNode *mphi = result->as_Phi();
     assert(mphi->bottom_type() == Type::MEMORY, "memory phi required");
     const TypePtr *t = mphi->adr_type();
     if (C->get_alias_index(t) != alias_idx) {
+      // Create a new Phi with the specified alias index type.
       result = split_memory_phi(mphi, alias_idx, orig_phis, phase);
+    } else if (!is_instance) {
+      // Push all non-instance Phis on the orig_phis worklist to update inputs
+      // during Phase 4 if needed.
+      orig_phis.append_if_missing(mphi);
     }
   }
   // the result is either MemNode, PhiNode, InitializeNode.
@@ -859,10 +864,14 @@ void ConnectionGraph::split_unique_types(GrowableArray<Node *>  &alloc_worklist)
           !n->is_CheckCastPP()) // not unique CheckCastPP.
         continue;
       // The inline code for Object.clone() casts the allocation result to
-      // java.lang.Object and then to the the actual type of the allocated
+      // java.lang.Object and then to the actual type of the allocated
       // object. Detect this case and use the second cast.
+      // Also detect j.l.reflect.Array.newInstance(jobject, jint) case when
+      // the allocation result is cast to java.lang.Object and then
+      // to the actual Array type.
       if (alloc->is_Allocate() && n->as_Type()->type() == TypeInstPtr::NOTNULL
-          && igvn->type(alloc->in(AllocateNode::KlassNode)) != TypeKlassPtr::OBJECT) {
+          && (alloc->is_AllocateArray() ||
+              igvn->type(alloc->in(AllocateNode::KlassNode)) != TypeKlassPtr::OBJECT)) {
         Node *cast2 = NULL;
         for (DUIterator_Fast imax, i = n->fast_outs(imax); i < imax; i++) {
           Node *use = n->fast_out(i);
@@ -878,7 +887,7 @@ void ConnectionGraph::split_unique_types(GrowableArray<Node *>  &alloc_worklist)
         }
       }
       set_escape_state(n->_idx, es);
-      // in order for an object to be stackallocatable, it must be:
+      // in order for an object to be scalar-replaceable, it must be:
       //   - a direct allocation (not a call returning an object)
       //   - non-escaping
       //   - eligible to be a unique type
@@ -888,7 +897,7 @@ void ConnectionGraph::split_unique_types(GrowableArray<Node *>  &alloc_worklist)
       const TypeOopPtr *t = igvn->type(n)->isa_oopptr();
       if (t == NULL)
         continue;  // not a TypeInstPtr
-      tinst = t->cast_to_instance_id(ni);
+      tinst = t->cast_to_exactness(true)->is_oopptr()->cast_to_instance_id(ni);
       igvn->hash_delete(n);
       igvn->set_type(n,  tinst);
       n->raise_bottom_type(tinst);
@@ -1204,8 +1213,8 @@ void ConnectionGraph::split_unique_types(GrowableArray<Node *>  &alloc_worklist)
   // to recursively process Phi's encounted on the input memory
   // chains as is done in split_memory_phi() since they  will
   // also be processed here.
-  while (orig_phis.length() != 0) {
-    PhiNode *phi = orig_phis.pop();
+  for (int j = 0; j < orig_phis.length(); j++) {
+    PhiNode *phi = orig_phis.at(j);
     int alias_idx = _compile->get_alias_index(phi->adr_type());
     igvn->hash_delete(phi);
     for (uint i = 1; i < phi->req(); i++) {

hotspot/src/share/vm/opto/macro.cpp

@@ -231,8 +231,7 @@ static Node *scan_mem_chain(Node *mem, int alias_idx, int offset, Node *start_me
     } else {
       return mem;
     }
-    if (mem == orig_mem)
-      return mem;
+    assert(mem != orig_mem, "dead memory loop");
   }
 }
 
@@ -241,21 +240,44 @@ static Node *scan_mem_chain(Node *mem, int alias_idx, int offset, Node *start_me
 // on the input paths.
 // Note: this function is recursive, its depth is limied by the "level" argument
 // Returns the computed Phi, or NULL if it cannot compute it.
-Node *PhaseMacroExpand::value_from_mem_phi(Node *mem, BasicType ft, const Type *phi_type, const TypeOopPtr *adr_t, Node *alloc, int level) {
-
-  if (level <= 0) {
-    return NULL;
-  }
+Node *PhaseMacroExpand::value_from_mem_phi(Node *mem, BasicType ft, const Type *phi_type, const TypeOopPtr *adr_t, Node *alloc, Node_Stack *value_phis, int level) {
+  assert(mem->is_Phi(), "sanity");
   int alias_idx = C->get_alias_index(adr_t);
   int offset = adr_t->offset();
   int instance_id = adr_t->instance_id();
 
+  // Check if an appropriate value phi already exists.
+  Node* region = mem->in(0);
+  for (DUIterator_Fast kmax, k = region->fast_outs(kmax); k < kmax; k++) {
+    Node* phi = region->fast_out(k);
+    if (phi->is_Phi() && phi != mem &&
+        phi->as_Phi()->is_same_inst_field(phi_type, instance_id, alias_idx, offset)) {
+      return phi;
+    }
+  }
+  // Check if an appropriate new value phi already exists.
+  Node* new_phi = NULL;
+  uint size = value_phis->size();
+  for (uint i=0; i < size; i++) {
+    if ( mem->_idx == value_phis->index_at(i) ) {
+      return value_phis->node_at(i);
+    }
+  }
+
+  if (level <= 0) {
+    return NULL;
+  }
   Node *start_mem = C->start()->proj_out(TypeFunc::Memory);
   Node *alloc_mem = alloc->in(TypeFunc::Memory);
 
   uint length = mem->req();
   GrowableArray <Node *> values(length, length, NULL);
 
+  // create a new Phi for the value
+  PhiNode *phi = new (C, length) PhiNode(mem->in(0), phi_type, NULL, instance_id, alias_idx, offset);
+  transform_later(phi);
+  value_phis->push(phi, mem->_idx);
+
   for (uint j = 1; j < length; j++) {
     Node *in = mem->in(j);
     if (in == NULL || in->is_top()) {
@@ -280,33 +302,17 @@ Node *PhaseMacroExpand::value_from_mem_phi(Node *mem, BasicType ft, const Type *
       } else if(val->is_Proj() && val->in(0) == alloc) {
         values.at_put(j, _igvn.zerocon(ft));
       } else if (val->is_Phi()) {
-        // Check if an appropriate node already exists.
-        Node* region = val->in(0);
-        Node* old_phi = NULL;
-        for (DUIterator_Fast kmax, k = region->fast_outs(kmax); k < kmax; k++) {
-          Node* phi = region->fast_out(k);
-          if (phi->is_Phi() && phi != val &&
-              phi->as_Phi()->is_same_inst_field(phi_type, instance_id, alias_idx, offset)) {
-            old_phi = phi;
-            break;
-          }
-        }
-        if (old_phi == NULL) {
-          val = value_from_mem_phi(val, ft, phi_type, adr_t, alloc, level-1);
-          if (val == NULL) {
-            return NULL;
-          }
-          values.at_put(j, val);
-        } else {
-          values.at_put(j, old_phi);
+        val = value_from_mem_phi(val, ft, phi_type, adr_t, alloc, value_phis, level-1);
+        if (val == NULL) {
+          return NULL;
         }
+        values.at_put(j, val);
       } else {
         return NULL;  // unknown node  on this path
       }
     }
   }
-  // create a new Phi for the value
-  PhiNode *phi = new (C, length) PhiNode(mem->in(0), phi_type, NULL, instance_id, alias_idx, offset);
+  // Set Phi's inputs
   for (uint j = 1; j < length; j++) {
     if (values.at(j) == mem) {
       phi->init_req(j, phi);
@@ -314,7 +320,6 @@ Node *PhaseMacroExpand::value_from_mem_phi(Node *mem, BasicType ft, const Type *
       phi->init_req(j, values.at(j));
     }
   }
-  transform_later(phi);
   return phi;
 }
 
@@ -329,7 +334,8 @@ Node *PhaseMacroExpand::value_from_mem(Node *sfpt_mem, BasicType ft, const Type
   Node *start_mem = C->start()->proj_out(TypeFunc::Memory);
   Node *alloc_ctrl = alloc->in(TypeFunc::Control);
   Node *alloc_mem = alloc->in(TypeFunc::Memory);
-  VectorSet visited(Thread::current()->resource_area());
+  Arena *a = Thread::current()->resource_area();
+  VectorSet visited(a);
 
 
   bool done = sfpt_mem == alloc_mem;
@@ -389,9 +395,18 @@ Node *PhaseMacroExpand::value_from_mem(Node *sfpt_mem, BasicType ft, const Type
       return mem->in(MemNode::ValueIn);
     } else if (mem->is_Phi()) {
       // attempt to produce a Phi reflecting the values on the input paths of the Phi
-      Node * phi = value_from_mem_phi(mem, ft, ftype, adr_t, alloc, 8);
+      Node_Stack value_phis(a, 8);
+      Node * phi = value_from_mem_phi(mem, ft, ftype, adr_t, alloc, &value_phis, 8);
       if (phi != NULL) {
         return phi;
+      } else {
+        // Kill all new Phis
+        while(value_phis.is_nonempty()) {
+          Node* n = value_phis.node();
+          _igvn.hash_delete(n);
+          _igvn.subsume_node(n, C->top());
+          value_phis.pop();
+        }
       }
     }
   }

hotspot/src/share/vm/opto/macro.hpp

@@ -79,7 +79,7 @@ private:
                               const TypeFunc* slow_call_type,
                               address slow_call_address);
   Node *value_from_mem(Node *mem, BasicType ft, const Type *ftype, const TypeOopPtr *adr_t, Node *alloc);
-  Node *value_from_mem_phi(Node *mem, BasicType ft, const Type *ftype, const TypeOopPtr *adr_t, Node *alloc, int level);
+  Node *value_from_mem_phi(Node *mem, BasicType ft, const Type *ftype, const TypeOopPtr *adr_t, Node *alloc, Node_Stack *value_phis, int level);
 
   bool eliminate_allocate_node(AllocateNode *alloc);
   bool can_eliminate_allocation(AllocateNode *alloc, GrowableArray <SafePointNode *>& safepoints);

hotspot/src/share/vm/opto/memnode.cpp

@@ -135,7 +135,9 @@ Node *MemNode::optimize_memory_chain(Node *mchain, const TypePtr *t_adr, PhaseGV
     const TypePtr *t = mphi->adr_type();
     if (t == TypePtr::BOTTOM || t == TypeRawPtr::BOTTOM ||
         t->isa_oopptr() && !t->is_oopptr()->is_known_instance() &&
-        t->is_oopptr()->cast_to_instance_id(t_oop->instance_id()) == t_oop) {
+        t->is_oopptr()->cast_to_exactness(true)
+         ->is_oopptr()->cast_to_ptr_type(t_oop->ptr())
+         ->is_oopptr()->cast_to_instance_id(t_oop->instance_id()) == t_oop) {
       // clone the Phi with our address type
       result = mphi->split_out_instance(t_adr, igvn);
     } else {

hotspot/src/share/vm/opto/node.hpp

@@ -1399,6 +1399,10 @@ public:
   uint index() const {
     return _inode_top->indx;
   }
+  uint index_at(uint i) const {
+    assert(_inodes + i <= _inode_top, "in range");
+    return _inodes[i].indx;
+  }
   void set_node(Node *n) {
     _inode_top->node = n;
   }

hotspot/src/share/vm/opto/type.cpp

@@ -2218,7 +2218,7 @@ const Type *TypeOopPtr::cast_to_ptr_type(PTR ptr) const {
   return make(ptr, _offset);
 }
 
-//-----------------------------cast_to_instance-------------------------------
+//-----------------------------cast_to_instance_id----------------------------
 const TypeOopPtr *TypeOopPtr::cast_to_instance_id(int instance_id) const {
   // There are no instances of a general oop.
   // Return self unchanged.
@@ -2610,8 +2610,7 @@ const TypeInstPtr *TypeInstPtr::make(PTR ptr,
   // Ptr is never Null
   assert( ptr != Null, "NULL pointers are not typed" );
 
-  if ( instance_id > 0 )
-    xk = true;  // instances are always exactly typed
+  assert(instance_id <= 0 || xk || !UseExactTypes, "instances are always exactly typed");
   if (!UseExactTypes)  xk = false;
   if (ptr == Constant) {
     // Note:  This case includes meta-object constants, such as methods.
@@ -2650,16 +2649,10 @@ const Type *TypeInstPtr::cast_to_exactness(bool klass_is_exact) const {
   return make(ptr(), klass(), klass_is_exact, const_oop(), _offset, _instance_id);
 }
 
-//-----------------------------cast_to_instance-------------------------------
+//-----------------------------cast_to_instance_id----------------------------
 const TypeOopPtr *TypeInstPtr::cast_to_instance_id(int instance_id) const {
   if( instance_id == _instance_id ) return this;
-  bool exact = _klass_is_exact;
-  PTR  ptr_t = _ptr;
-  if ( instance_id > 0 ) { // instances are always exactly typed
-    if (UseExactTypes) exact = true;
-    ptr_t = NotNull;
-  }
-  return make(ptr_t, klass(), exact, const_oop(), _offset, instance_id);
+  return make(_ptr, klass(), _klass_is_exact, const_oop(), _offset, instance_id);
 }
 
 //------------------------------xmeet_unloaded---------------------------------
@@ -2899,6 +2892,7 @@ const Type *TypeInstPtr::xmeet( const Type *t ) const {
         xk = above_centerline(ptr) ? tinst_xk : false;
         // Watch out for Constant vs. AnyNull interface.
         if (ptr == Constant)  ptr = NotNull;   // forget it was a constant
+        instance_id = InstanceBot;
       }
       ciObject* o = NULL;  // the Constant value, if any
       if (ptr == Constant) {
@@ -2989,6 +2983,7 @@ const Type *TypeInstPtr::xmeet( const Type *t ) const {
     // class hierarchy - which means we have to fall to at least NotNull.
     if( ptr == TopPTR || ptr == AnyNull || ptr == Constant )
       ptr = NotNull;
+    instance_id = InstanceBot;
 
     // Now we find the LCA of Java classes
     ciKlass* k = this_klass->least_common_ancestor(tinst_klass);
@@ -3101,8 +3096,7 @@ const TypeAryPtr *TypeAryPtr::make( PTR ptr, const TypeAry *ary, ciKlass* k, boo
   assert(!(k == NULL && ary->_elem->isa_int()),
          "integral arrays must be pre-equipped with a class");
   if (!xk)  xk = ary->ary_must_be_exact();
-  if ( instance_id > 0 )
-    xk = true;  // instances are always exactly typed
+  assert(instance_id <= 0 || xk || !UseExactTypes, "instances are always exactly typed");
   if (!UseExactTypes)  xk = (ptr == Constant);
   return (TypeAryPtr*)(new TypeAryPtr(ptr, NULL, ary, k, xk, offset, instance_id))->hashcons();
 }
@@ -3113,8 +3107,7 @@ const TypeAryPtr *TypeAryPtr::make( PTR ptr, ciObject* o, const TypeAry *ary, ci
          "integral arrays must be pre-equipped with a class");
   assert( (ptr==Constant && o) || (ptr!=Constant && !o), "" );
   if (!xk)  xk = (o != NULL) || ary->ary_must_be_exact();
-  if ( instance_id > 0 )
-    xk = true;  // instances are always exactly typed
+  assert(instance_id <= 0 || xk || !UseExactTypes, "instances are always exactly typed");
   if (!UseExactTypes)  xk = (ptr == Constant);
   return (TypeAryPtr*)(new TypeAryPtr(ptr, o, ary, k, xk, offset, instance_id))->hashcons();
 }
@@ -3134,16 +3127,10 @@ const Type *TypeAryPtr::cast_to_exactness(bool klass_is_exact) const {
   return make(ptr(), const_oop(), _ary, klass(), klass_is_exact, _offset, _instance_id);
 }
 
-//-----------------------------cast_to_instance-------------------------------
+//-----------------------------cast_to_instance_id----------------------------
 const TypeOopPtr *TypeAryPtr::cast_to_instance_id(int instance_id) const {
   if( instance_id == _instance_id ) return this;
-  bool exact = _klass_is_exact;
-  PTR  ptr_t = _ptr;
-  if ( instance_id > 0 ) { // instances are always exactly typed
-    if (UseExactTypes) exact = true;
-    ptr_t = NotNull;
-  }
-  return make(ptr_t, const_oop(), _ary, klass(), exact, _offset, instance_id);
+  return make(_ptr, const_oop(), _ary, klass(), _klass_is_exact, _offset, instance_id);
 }
 
 //-----------------------------narrow_size_type-------------------------------
@@ -3300,6 +3287,7 @@ const Type *TypeAryPtr::xmeet( const Type *t ) const {
       } else {
         // Something like byte[int+] meets char[int+].
         // This must fall to bottom, not (int[-128..65535])[int+].
+        instance_id = InstanceBot;
         tary = TypeAry::make(Type::BOTTOM, tary->_size);
       }
     }
@@ -3316,6 +3304,7 @@ const Type *TypeAryPtr::xmeet( const Type *t ) const {
         if( tap->const_oop() != NULL && !o->equals(tap->const_oop()) ) {
           ptr = NotNull;
           o = NULL;
+          instance_id = InstanceBot;
         }
       } else if( above_centerline(_ptr) ) {
         o = tap->const_oop();

hotspot/test/compiler/6724218/Test.java

+/*
+ * Copyright 2008 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+/*
+ * @test
+ * @bug 6724218
+ * @summary Fix raise_LCA_above_marks() early termination
+ * @run main/othervm -Xbatch -XX:CompileCommand=exclude,Test.update Test
+ */
+
+public class Test {
+    Test   next  = null;
+    Object value = null;
+
+    static boolean _closed = false;
+    static int size = 0;
+    static Test list  = null;
+    static int cache_size = 0;
+    static Test cache = null;
+
+    Object get(int i) {
+        Test t = list;
+        list = t.next;
+        size -= 1;
+        Object o = t.value;
+        if (i > 0) {
+            t.next = cache;
+            t.value = null;
+            cache = t;
+            cache_size = +1;
+        }
+        return o;
+    }
+
+    void update() {
+        // Exclude compilation of this one.
+        if (size == 0) {
+            Test t;
+            if (cache_size > 0) {
+                t = cache;
+                cache = t.next;
+                cache_size = -1;
+            } else {
+                t = new Test();
+            }
+            t.value = new Object();
+            t.next = list;
+            list = t;
+            size += 1;
+        }
+    }
+
+    synchronized Object test(int i) {
+        while (true) {
+            if (_closed) {
+                return null;
+            } else if (size > 0) {
+                return get(i);
+            }
+            update();
+        }
+    }
+
+    public static void main(String argv[]) throws Exception {
+        Test t = new Test();
+        int lim = 500000;
+        Object o;
+        for (int j = 0; j < lim; j++) {
+            o = t.test(j&1);
+            if (o == null) {
+              throw new Exception("*** Failed on iteration " + j);
+            }
+            if ((j&1) == 0) {
+              t.update();
+            }
+        }
+    }
+}