jdk8-mips64-public/hotspot: src/share/vm/opto/node.hpp@97d09139b360 (annotated)

src/share/vm/opto/node.hpp@97d09139b360 (annotated)

src/share/vm/opto/node.hpp

Tue, 10 Mar 2020 10:46:35 +0100

author: mdoerr
date: Tue, 10 Mar 2020 10:46:35 +0100
changeset 9912: 97d09139b360
parent 8504: a96cf90239c6
child 9931: fd44df5e3bc3
child 9952: 19056c781208
permissions: -rw-r--r--

8146612: C2: Precedence edges specification violated
Reviewed-by: kvn

 /*
  * Copyright (c) 1997, 2016, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  *
  */
 #ifndef SHARE_VM_OPTO_NODE_HPP
 #define SHARE_VM_OPTO_NODE_HPP
 #include "libadt/port.hpp"
 #include "libadt/vectset.hpp"
 #include "opto/compile.hpp"
 #include "opto/type.hpp"
 // Portions of code courtesy of Clifford Click
 // Optimization - Graph Style
 class AbstractLockNode;
 class AddNode;
 class AddPNode;
 class AliasInfo;
 class AllocateArrayNode;
 class AllocateNode;
 class Block;
 class BoolNode;
 class BoxLockNode;
 class CMoveNode;
 class CallDynamicJavaNode;
 class CallJavaNode;
 class CallLeafNode;
 class CallNode;
 class CallRuntimeNode;
 class CallStaticJavaNode;
 class CatchNode;
 class CatchProjNode;
 class CheckCastPPNode;
 class CastIINode;
 class ClearArrayNode;
 class CmpNode;
 class CodeBuffer;
 class ConstraintCastNode;
 class ConNode;
 class CountedLoopNode;
 class CountedLoopEndNode;
 class DecodeNarrowPtrNode;
 class DecodeNNode;
 class DecodeNKlassNode;
 class EncodeNarrowPtrNode;
 class EncodePNode;
 class EncodePKlassNode;
 class FastLockNode;
 class FastUnlockNode;
 class IfNode;
 class IfFalseNode;
 class IfTrueNode;
 class InitializeNode;
 class JVMState;
 class JumpNode;
 class JumpProjNode;
 class LoadNode;
 class LoadStoreNode;
 class LockNode;
 class LoopNode;
 class MachBranchNode;
 class MachCallDynamicJavaNode;
 class MachCallJavaNode;
 class MachCallLeafNode;
 class MachCallNode;
 class MachCallRuntimeNode;
 class MachCallStaticJavaNode;
 class MachConstantBaseNode;
 class MachConstantNode;
 class MachGotoNode;
 class MachIfNode;
 class MachNode;
 class MachNullCheckNode;
 class MachProjNode;
 class MachReturnNode;
 class MachSafePointNode;
 class MachSpillCopyNode;
 class MachTempNode;
 class MachMergeNode;
 class Matcher;
 class MemBarNode;
 class MemBarStoreStoreNode;
 class MemNode;
 class MergeMemNode;
 class MulNode;
 class MultiNode;
 class MultiBranchNode;
 class NeverBranchNode;
 class Node;
 class Node_Array;
 class Node_List;
 class Node_Stack;
 class NullCheckNode;
 class OopMap;
 class ParmNode;
 class PCTableNode;
 class PhaseCCP;
 class PhaseGVN;
 class PhaseIterGVN;
 class PhaseRegAlloc;
 class PhaseTransform;
 class PhaseValues;
 class PhiNode;
 class Pipeline;
 class ProjNode;
 class RegMask;
 class RegionNode;
 class RootNode;
 class SafePointNode;
 class SafePointScalarObjectNode;
 class StartNode;
 class State;
 class StoreNode;
 class SubNode;
 class Type;
 class TypeNode;
 class UnlockNode;
 class VectorNode;
 class LoadVectorNode;
 class StoreVectorNode;
 class VectorSet;
 typedef void (*NFunc)(Node&,void*);
 extern "C" {
   typedef int (*C_sort_func_t)(const void *, const void *);
 }
 // The type of all node counts and indexes.
 // It must hold at least 16 bits, but must also be fast to load and store.
 // This type, if less than 32 bits, could limit the number of possible nodes.
 // (To make this type platform-specific, move to globalDefinitions_xxx.hpp.)
 typedef unsigned int node_idx_t;
 #ifndef OPTO_DU_ITERATOR_ASSERT
 #ifdef ASSERT
 #define OPTO_DU_ITERATOR_ASSERT 1
 #else
 #define OPTO_DU_ITERATOR_ASSERT 0
 #endif
 #endif //OPTO_DU_ITERATOR_ASSERT
 #if OPTO_DU_ITERATOR_ASSERT
 class DUIterator;
 class DUIterator_Fast;
 class DUIterator_Last;
 #else
 typedef uint   DUIterator;
 typedef Node** DUIterator_Fast;
 typedef Node** DUIterator_Last;
 #endif
 // Node Sentinel
 #define NodeSentinel (Node*)-1
 // Unknown count frequency
 #define COUNT_UNKNOWN (-1.0f)
 //------------------------------Node-------------------------------------------
 // Nodes define actions in the program.  They create values, which have types.
 // They are both vertices in a directed graph and program primitives.  Nodes
 // are labeled; the label is the "opcode", the primitive function in the lambda
 // calculus sense that gives meaning to the Node.  Node inputs are ordered (so
 // that "a-b" is different from "b-a").  The inputs to a Node are the inputs to
 // the Node's function.  These inputs also define a Type equation for the Node.
 // Solving these Type equations amounts to doing dataflow analysis.
 // Control and data are uniformly represented in the graph.  Finally, Nodes
 // have a unique dense integer index which is used to index into side arrays
 // whenever I have phase-specific information.
 class Node {
   friend class VMStructs;
   // Lots of restrictions on cloning Nodes
   Node(const Node&);            // not defined; linker error to use these
   Node &operator=(const Node &rhs);
 public:
   friend class Compile;
   #if OPTO_DU_ITERATOR_ASSERT
   friend class DUIterator_Common;
   friend class DUIterator;
   friend class DUIterator_Fast;
   friend class DUIterator_Last;
   #endif
   // Because Nodes come and go, I define an Arena of Node structures to pull
   // from.  This should allow fast access to node creation & deletion.  This
   // field is a local cache of a value defined in some "program fragment" for
   // which these Nodes are just a part of.
   // New Operator that takes a Compile pointer, this will eventually
   // be the "new" New operator.
   inline void* operator new( size_t x, Compile* C) throw() {
     Node* n = (Node*)C->node_arena()->Amalloc_D(x);
 #ifdef ASSERT
     n->_in = (Node**)n; // magic cookie for assertion check
 #endif
     n->_out = (Node**)C;
     return (void*)n;
   }
   // Delete is a NOP
   void operator delete( void *ptr ) {}
   // Fancy destructor; eagerly attempt to reclaim Node numberings and storage
   void destruct();
   // Create a new Node.  Required is the number is of inputs required for
   // semantic correctness.
   Node( uint required );
   // Create a new Node with given input edges.
   // This version requires use of the "edge-count" new.
   // E.g.  new (C,3) FooNode( C, NULL, left, right );
   Node( Node *n0 );
   Node( Node *n0, Node *n1 );
   Node( Node *n0, Node *n1, Node *n2 );
   Node( Node *n0, Node *n1, Node *n2, Node *n3 );
   Node( Node *n0, Node *n1, Node *n2, Node *n3, Node *n4 );
   Node( Node *n0, Node *n1, Node *n2, Node *n3, Node *n4, Node *n5 );
   Node( Node *n0, Node *n1, Node *n2, Node *n3,
             Node *n4, Node *n5, Node *n6 );
   // Clone an inherited Node given only the base Node type.
   Node* clone() const;
   // Clone a Node, immediately supplying one or two new edges.
   // The first and second arguments, if non-null, replace in(1) and in(2),
   // respectively.
   Node* clone_with_data_edge(Node* in1, Node* in2 = NULL) const {
     Node* nn = clone();
     if (in1 != NULL)  nn->set_req(1, in1);
     if (in2 != NULL)  nn->set_req(2, in2);
     return nn;
   }
 private:
   // Shared setup for the above constructors.
   // Handles all interactions with Compile::current.
   // Puts initial values in all Node fields except _idx.
   // Returns the initial value for _idx, which cannot
   // be initialized by assignment.
   inline int Init(int req, Compile* C);
 //----------------- input edge handling
 protected:
   friend class PhaseCFG;        // Access to address of _in array elements
   Node **_in;                   // Array of use-def references to Nodes
   Node **_out;                  // Array of def-use references to Nodes
   // Input edges are split into two categories.  Required edges are required
   // for semantic correctness; order is important and NULLs are allowed.
   // Precedence edges are used to help determine execution order and are
   // added, e.g., for scheduling purposes.  They are unordered and not
   // duplicated; they have no embedded NULLs.  Edges from 0 to _cnt-1
   // are required, from _cnt to _max-1 are precedence edges.
   node_idx_t _cnt;              // Total number of required Node inputs.
   node_idx_t _max;              // Actual length of input array.
   // Output edges are an unordered list of def-use edges which exactly
   // correspond to required input edges which point from other nodes
   // to this one.  Thus the count of the output edges is the number of
   // users of this node.
   node_idx_t _outcnt;           // Total number of Node outputs.
   node_idx_t _outmax;           // Actual length of output array.
   // Grow the actual input array to the next larger power-of-2 bigger than len.
   void grow( uint len );
   // Grow the output array to the next larger power-of-2 bigger than len.
   void out_grow( uint len );
  public:
   // Each Node is assigned a unique small/dense number.  This number is used
   // to index into auxiliary arrays of data and bit vectors.
   // The field _idx is declared constant to defend against inadvertent assignments,
   // since it is used by clients as a naked field. However, the field's value can be
   // changed using the set_idx() method.
   //
   // The PhaseRenumberLive phase renumbers nodes based on liveness information.
   // Therefore, it updates the value of the _idx field. The parse-time _idx is
   // preserved in _parse_idx.
   const node_idx_t _idx;
   DEBUG_ONLY(const node_idx_t _parse_idx;)
   // Get the (read-only) number of input edges
   uint req() const { return _cnt; }
   uint len() const { return _max; }
   // Get the (read-only) number of output edges
   uint outcnt() const { return _outcnt; }
 #if OPTO_DU_ITERATOR_ASSERT
   // Iterate over the out-edges of this node.  Deletions are illegal.
   inline DUIterator outs() const;
   // Use this when the out array might have changed to suppress asserts.
   inline DUIterator& refresh_out_pos(DUIterator& i) const;
   // Does the node have an out at this position?  (Used for iteration.)
   inline bool has_out(DUIterator& i) const;
   inline Node*    out(DUIterator& i) const;
   // Iterate over the out-edges of this node.  All changes are illegal.
   inline DUIterator_Fast fast_outs(DUIterator_Fast& max) const;
   inline Node*    fast_out(DUIterator_Fast& i) const;
   // Iterate over the out-edges of this node, deleting one at a time.
   inline DUIterator_Last last_outs(DUIterator_Last& min) const;
   inline Node*    last_out(DUIterator_Last& i) const;
   // The inline bodies of all these methods are after the iterator definitions.
 #else
   // Iterate over the out-edges of this node.  Deletions are illegal.
   // This iteration uses integral indexes, to decouple from array reallocations.
   DUIterator outs() const  { return 0; }
   // Use this when the out array might have changed to suppress asserts.
   DUIterator refresh_out_pos(DUIterator i) const { return i; }
   // Reference to the i'th output Node.  Error if out of bounds.
   Node*    out(DUIterator i) const { assert(i < _outcnt, "oob"); return _out[i]; }
   // Does the node have an out at this position?  (Used for iteration.)
   bool has_out(DUIterator i) const { return i < _outcnt; }
   // Iterate over the out-edges of this node.  All changes are illegal.
   // This iteration uses a pointer internal to the out array.
   DUIterator_Fast fast_outs(DUIterator_Fast& max) const {
     Node** out = _out;
     // Assign a limit pointer to the reference argument:
     max = out + (ptrdiff_t)_outcnt;
     // Return the base pointer:
     return out;
   }
   Node*    fast_out(DUIterator_Fast i) const  { return *i; }
   // Iterate over the out-edges of this node, deleting one at a time.
   // This iteration uses a pointer internal to the out array.
   DUIterator_Last last_outs(DUIterator_Last& min) const {
     Node** out = _out;
     // Assign a limit pointer to the reference argument:
     min = out;
     // Return the pointer to the start of the iteration:
     return out + (ptrdiff_t)_outcnt - 1;
   }
   Node*    last_out(DUIterator_Last i) const  { return *i; }
 #endif
   // Reference to the i'th input Node.  Error if out of bounds.
   Node* in(uint i) const { assert(i < _max, err_msg_res("oob: i=%d, _max=%d", i, _max)); return _in[i]; }
   // Reference to the i'th input Node.  NULL if out of bounds.
   Node* lookup(uint i) const { return ((i < _max) ? _in[i] : NULL); }
   // Reference to the i'th output Node.  Error if out of bounds.
   // Use this accessor sparingly.  We are going trying to use iterators instead.
   Node* raw_out(uint i) const { assert(i < _outcnt,"oob"); return _out[i]; }
   // Return the unique out edge.
   Node* unique_out() const { assert(_outcnt==1,"not unique"); return _out[0]; }
   // Delete out edge at position 'i' by moving last out edge to position 'i'
   void  raw_del_out(uint i) {
     assert(i < _outcnt,"oob");
     assert(_outcnt > 0,"oob");
     #if OPTO_DU_ITERATOR_ASSERT
     // Record that a change happened here.
     debug_only(_last_del = _out[i]; ++_del_tick);
     #endif
     _out[i] = _out[--_outcnt];
     // Smash the old edge so it can't be used accidentally.
     debug_only(_out[_outcnt] = (Node *)(uintptr_t)0xdeadbeef);
   }
 #ifdef ASSERT
   bool is_dead() const;
 #define is_not_dead(n) ((n) == NULL || !VerifyIterativeGVN || !((n)->is_dead()))
 #endif
   // Check whether node has become unreachable
   bool is_unreachable(PhaseIterGVN &igvn) const;
   // Set a required input edge, also updates corresponding output edge
   void add_req( Node *n ); // Append a NEW required input
   void add_req( Node *n0, Node *n1 ) {
     add_req(n0); add_req(n1); }
   void add_req( Node *n0, Node *n1, Node *n2 ) {
     add_req(n0); add_req(n1); add_req(n2); }
   void add_req_batch( Node* n, uint m ); // Append m NEW required inputs (all n).
   void del_req( uint idx ); // Delete required edge & compact
   void del_req_ordered( uint idx ); // Delete required edge & compact with preserved order
   void ins_req( uint i, Node *n ); // Insert a NEW required input
   void set_req( uint i, Node *n ) {
     assert( is_not_dead(n), "can not use dead node");
     assert( i < _cnt, err_msg_res("oob: i=%d, _cnt=%d", i, _cnt));
     assert( !VerifyHashTableKeys || _hash_lock == 0,
             "remove node from hash table before modifying it");
     Node** p = &_in[i];    // cache this._in, across the del_out call
     if (*p != NULL)  (*p)->del_out((Node *)this);
     (*p) = n;
     if (n != NULL)      n->add_out((Node *)this);
   }
   // Light version of set_req() to init inputs after node creation.
   void init_req( uint i, Node *n ) {
     assert( i == 0 && this == n ||
             is_not_dead(n), "can not use dead node");
     assert( i < _cnt, "oob");
     assert( !VerifyHashTableKeys || _hash_lock == 0,
             "remove node from hash table before modifying it");
     assert( _in[i] == NULL, "sanity");
     _in[i] = n;
     if (n != NULL)      n->add_out((Node *)this);
   }
   // Find first occurrence of n among my edges:
   int find_edge(Node* n);
   int find_prec_edge(Node* n) {
     for (uint i = req(); i < len(); i++) {
       if (_in[i] == n) return i;
       if (_in[i] == NULL) {
         DEBUG_ONLY( while ((++i) < len()) assert(_in[i] == NULL, "Gap in prec edges!"); )
         break;
       }
     }
     return -1;
   }
   int replace_edge(Node* old, Node* neww);
   int replace_edges_in_range(Node* old, Node* neww, int start, int end);
   // NULL out all inputs to eliminate incoming Def-Use edges.
   // Return the number of edges between 'n' and 'this'
   int  disconnect_inputs(Node *n, Compile *c);
   // Quickly, return true if and only if I am Compile::current()->top().
   bool is_top() const {
     assert((this == (Node*) Compile::current()->top()) == (_out == NULL), "");
     return (_out == NULL);
   }
   // Reaffirm invariants for is_top.  (Only from Compile::set_cached_top_node.)
   void setup_is_top();
   // Strip away casting.  (It is depth-limited.)
   Node* uncast() const;
   // Return whether two Nodes are equivalent, after stripping casting.
   bool eqv_uncast(const Node* n) const {
     return (this->uncast() == n->uncast());
   }
 private:
   static Node* uncast_helper(const Node* n);
   // Add an output edge to the end of the list
   void add_out( Node *n ) {
     if (is_top())  return;
     if( _outcnt == _outmax ) out_grow(_outcnt);
     _out[_outcnt++] = n;
   }
   // Delete an output edge
   void del_out( Node *n ) {
     if (is_top())  return;
     Node** outp = &_out[_outcnt];
     // Find and remove n
     do {
       assert(outp > _out, "Missing Def-Use edge");
     } while (*--outp != n);
     *outp = _out[--_outcnt];
     // Smash the old edge so it can't be used accidentally.
     debug_only(_out[_outcnt] = (Node *)(uintptr_t)0xdeadbeef);
     // Record that a change happened here.
     #if OPTO_DU_ITERATOR_ASSERT
     debug_only(_last_del = n; ++_del_tick);
     #endif
   }
   // Close gap after removing edge.
   void close_prec_gap_at(uint gap) {
     assert(_cnt <= gap && gap < _max, "no valid prec edge");
     uint i = gap;
     Node *last = NULL;
     for (; i < _max-1; ++i) {
       Node *next = _in[i+1];
       if (next == NULL) break;
       last = next;
     }
     _in[gap] = last; // Move last slot to empty one.
     _in[i] = NULL;   // NULL out last slot.
   }
 public:
   // Globally replace this node by a given new node, updating all uses.
   void replace_by(Node* new_node);
   // Globally replace this node by a given new node, updating all uses
   // and cutting input edges of old node.
   void subsume_by(Node* new_node, Compile* c) {
     replace_by(new_node);
     disconnect_inputs(NULL, c);
   }
   void set_req_X( uint i, Node *n, PhaseIterGVN *igvn );
   // Find the one non-null required input.  RegionNode only
   Node *nonnull_req() const;
   // Add or remove precedence edges
   void add_prec( Node *n );
   void rm_prec( uint i );
   // Note: prec(i) will not necessarily point to n if edge already exists.
   void set_prec( uint i, Node *n ) {
     assert(i < _max, err_msg("oob: i=%d, _max=%d", i, _max));
     assert(is_not_dead(n), "can not use dead node");
     assert(i >= _cnt, "not a precedence edge");
     // Avoid spec violation: duplicated prec edge.
     if (_in[i] == n) return;
     if (n == NULL || find_prec_edge(n) != -1) {
       rm_prec(i);
       return;
     }
     if (_in[i] != NULL) _in[i]->del_out((Node *)this);
     _in[i] = n;
     if (n != NULL) n->add_out((Node *)this);
   }
   // Set this node's index, used by cisc_version to replace current node
   void set_idx(uint new_idx) {
     const node_idx_t* ref = &_idx;
     *(node_idx_t*)ref = new_idx;
   }
   // Swap input edge order.  (Edge indexes i1 and i2 are usually 1 and 2.)
   void swap_edges(uint i1, uint i2) {
     debug_only(uint check_hash = (VerifyHashTableKeys && _hash_lock) ? hash() : NO_HASH);
     // Def-Use info is unchanged
     Node* n1 = in(i1);
     Node* n2 = in(i2);
     _in[i1] = n2;
     _in[i2] = n1;
     // If this node is in the hash table, make sure it doesn't need a rehash.
     assert(check_hash == NO_HASH || check_hash == hash(), "edge swap must preserve hash code");
   }
   // Iterators over input Nodes for a Node X are written as:
   // for( i = 0; i < X.req(); i++ ) ... X[i] ...
   // NOTE: Required edges can contain embedded NULL pointers.
 //----------------- Other Node Properties
   // Generate class id for some ideal nodes to avoid virtual query
   // methods is_<Node>().
   // Class id is the set of bits corresponded to the node class and all its
   // super classes so that queries for super classes are also valid.
   // Subclasses of the same super class have different assigned bit
   // (the third parameter in the macro DEFINE_CLASS_ID).
   // Classes with deeper hierarchy are declared first.
   // Classes with the same hierarchy depth are sorted by usage frequency.
   //
   // The query method masks the bits to cut off bits of subclasses
   // and then compare the result with the class id
   // (see the macro DEFINE_CLASS_QUERY below).
   //
   //  Class_MachCall=30, ClassMask_MachCall=31
   // 12               8               4               0
   //  0   0   0   0   0   0   0   0   1   1   1   1   0
   //                                  |   |   |   |
   //                                  |   |   |   Bit_Mach=2
   //                                  |   |   Bit_MachReturn=4
   //                                  |   Bit_MachSafePoint=8
   //                                  Bit_MachCall=16
   //
   //  Class_CountedLoop=56, ClassMask_CountedLoop=63
   // 12               8               4               0
   //  0   0   0   0   0   0   0   1   1   1   0   0   0
   //                              |   |   |
   //                              |   |   Bit_Region=8
   //                              |   Bit_Loop=16
   //                              Bit_CountedLoop=32
   #define DEFINE_CLASS_ID(cl, supcl, subn) \
   Bit_##cl = (Class_##supcl == 0) ? 1 << subn : (Bit_##supcl) << (1 + subn) , \
   Class_##cl = Class_##supcl + Bit_##cl , \
   ClassMask_##cl = ((Bit_##cl << 1) - 1) ,
   // This enum is used only for C2 ideal and mach nodes with is_<node>() methods
   // so that it's values fits into 16 bits.
   enum NodeClasses {
     Bit_Node   = 0x0000,
     Class_Node = 0x0000,
     ClassMask_Node = 0xFFFF,
     DEFINE_CLASS_ID(Multi, Node, 0)
       DEFINE_CLASS_ID(SafePoint, Multi, 0)
         DEFINE_CLASS_ID(Call,      SafePoint, 0)
           DEFINE_CLASS_ID(CallJava,         Call, 0)
             DEFINE_CLASS_ID(CallStaticJava,   CallJava, 0)
             DEFINE_CLASS_ID(CallDynamicJava,  CallJava, 1)
           DEFINE_CLASS_ID(CallRuntime,      Call, 1)
             DEFINE_CLASS_ID(CallLeaf,         CallRuntime, 0)
           DEFINE_CLASS_ID(Allocate,         Call, 2)
             DEFINE_CLASS_ID(AllocateArray,    Allocate, 0)
           DEFINE_CLASS_ID(AbstractLock,     Call, 3)
             DEFINE_CLASS_ID(Lock,             AbstractLock, 0)
             DEFINE_CLASS_ID(Unlock,           AbstractLock, 1)
       DEFINE_CLASS_ID(MultiBranch, Multi, 1)
         DEFINE_CLASS_ID(PCTable,     MultiBranch, 0)
           DEFINE_CLASS_ID(Catch,       PCTable, 0)
           DEFINE_CLASS_ID(Jump,        PCTable, 1)
         DEFINE_CLASS_ID(If,          MultiBranch, 1)
           DEFINE_CLASS_ID(CountedLoopEnd, If, 0)
         DEFINE_CLASS_ID(NeverBranch, MultiBranch, 2)
       DEFINE_CLASS_ID(Start,       Multi, 2)
       DEFINE_CLASS_ID(MemBar,      Multi, 3)
         DEFINE_CLASS_ID(Initialize,       MemBar, 0)
         DEFINE_CLASS_ID(MemBarStoreStore, MemBar, 1)
     DEFINE_CLASS_ID(Mach,  Node, 1)
       DEFINE_CLASS_ID(MachReturn, Mach, 0)
         DEFINE_CLASS_ID(MachSafePoint, MachReturn, 0)
           DEFINE_CLASS_ID(MachCall, MachSafePoint, 0)
             DEFINE_CLASS_ID(MachCallJava,         MachCall, 0)
               DEFINE_CLASS_ID(MachCallStaticJava,   MachCallJava, 0)
               DEFINE_CLASS_ID(MachCallDynamicJava,  MachCallJava, 1)
             DEFINE_CLASS_ID(MachCallRuntime,      MachCall, 1)
               DEFINE_CLASS_ID(MachCallLeaf,         MachCallRuntime, 0)
       DEFINE_CLASS_ID(MachBranch, Mach, 1)
         DEFINE_CLASS_ID(MachIf,         MachBranch, 0)
         DEFINE_CLASS_ID(MachGoto,       MachBranch, 1)
         DEFINE_CLASS_ID(MachNullCheck,  MachBranch, 2)
       DEFINE_CLASS_ID(MachSpillCopy,    Mach, 2)
       DEFINE_CLASS_ID(MachTemp,         Mach, 3)
       DEFINE_CLASS_ID(MachConstantBase, Mach, 4)
       DEFINE_CLASS_ID(MachConstant,     Mach, 5)
       DEFINE_CLASS_ID(MachMerge,        Mach, 6)
     DEFINE_CLASS_ID(Type,  Node, 2)
       DEFINE_CLASS_ID(Phi,   Type, 0)
       DEFINE_CLASS_ID(ConstraintCast, Type, 1)
         DEFINE_CLASS_ID(CastII, ConstraintCast, 0)
       DEFINE_CLASS_ID(CheckCastPP, Type, 2)
       DEFINE_CLASS_ID(CMove, Type, 3)
       DEFINE_CLASS_ID(SafePointScalarObject, Type, 4)
       DEFINE_CLASS_ID(DecodeNarrowPtr, Type, 5)
         DEFINE_CLASS_ID(DecodeN, DecodeNarrowPtr, 0)
         DEFINE_CLASS_ID(DecodeNKlass, DecodeNarrowPtr, 1)
       DEFINE_CLASS_ID(EncodeNarrowPtr, Type, 6)
         DEFINE_CLASS_ID(EncodeP, EncodeNarrowPtr, 0)
         DEFINE_CLASS_ID(EncodePKlass, EncodeNarrowPtr, 1)
     DEFINE_CLASS_ID(Proj,  Node, 3)
       DEFINE_CLASS_ID(CatchProj, Proj, 0)
       DEFINE_CLASS_ID(JumpProj,  Proj, 1)
       DEFINE_CLASS_ID(IfTrue,    Proj, 2)
       DEFINE_CLASS_ID(IfFalse,   Proj, 3)
       DEFINE_CLASS_ID(Parm,      Proj, 4)
       DEFINE_CLASS_ID(MachProj,  Proj, 5)
     DEFINE_CLASS_ID(Mem,   Node, 4)
       DEFINE_CLASS_ID(Load,  Mem, 0)
         DEFINE_CLASS_ID(LoadVector,  Load, 0)
       DEFINE_CLASS_ID(Store, Mem, 1)
         DEFINE_CLASS_ID(StoreVector, Store, 0)
       DEFINE_CLASS_ID(LoadStore, Mem, 2)
     DEFINE_CLASS_ID(Region, Node, 5)
       DEFINE_CLASS_ID(Loop, Region, 0)
         DEFINE_CLASS_ID(Root,        Loop, 0)
         DEFINE_CLASS_ID(CountedLoop, Loop, 1)
     DEFINE_CLASS_ID(Sub,   Node, 6)
       DEFINE_CLASS_ID(Cmp,   Sub, 0)
         DEFINE_CLASS_ID(FastLock,   Cmp, 0)
         DEFINE_CLASS_ID(FastUnlock, Cmp, 1)
     DEFINE_CLASS_ID(MergeMem, Node, 7)
     DEFINE_CLASS_ID(Bool,     Node, 8)
     DEFINE_CLASS_ID(AddP,     Node, 9)
     DEFINE_CLASS_ID(BoxLock,  Node, 10)
     DEFINE_CLASS_ID(Add,      Node, 11)
     DEFINE_CLASS_ID(Mul,      Node, 12)
     DEFINE_CLASS_ID(Vector,   Node, 13)
     DEFINE_CLASS_ID(ClearArray, Node, 14)
     _max_classes  = ClassMask_ClearArray
   };
   #undef DEFINE_CLASS_ID
   // Flags are sorted by usage frequency.
   enum NodeFlags {
     Flag_is_Copy                     = 0x01, // should be first bit to avoid shift
     Flag_rematerialize               = Flag_is_Copy << 1,
     Flag_needs_anti_dependence_check = Flag_rematerialize << 1,
     Flag_is_macro                    = Flag_needs_anti_dependence_check << 1,
     Flag_is_Con                      = Flag_is_macro << 1,
     Flag_is_cisc_alternate           = Flag_is_Con << 1,
     Flag_is_dead_loop_safe           = Flag_is_cisc_alternate << 1,
     Flag_may_be_short_branch         = Flag_is_dead_loop_safe << 1,
     Flag_avoid_back_to_back_before   = Flag_may_be_short_branch << 1,
     Flag_avoid_back_to_back_after    = Flag_avoid_back_to_back_before << 1,
     Flag_has_call                    = Flag_avoid_back_to_back_after << 1,
     Flag_is_expensive                = Flag_has_call << 1,
     _max_flags = (Flag_is_expensive << 1) - 1 // allow flags combination
   };
 private:
   jushort _class_id;
   jushort _flags;
 protected:
   // These methods should be called from constructors only.
   void init_class_id(jushort c) {
     assert(c <= _max_classes, "invalid node class");
     _class_id = c; // cast out const
   }
   void init_flags(jushort fl) {
     assert(fl <= _max_flags, "invalid node flag");
     _flags |= fl;
   }
   void clear_flag(jushort fl) {
     assert(fl <= _max_flags, "invalid node flag");
     _flags &= ~fl;
   }
 public:
   const jushort class_id() const { return _class_id; }
   const jushort flags() const { return _flags; }
   // Return a dense integer opcode number
   virtual int Opcode() const;
   // Virtual inherited Node size
   virtual uint size_of() const;
   // Other interesting Node properties
   #define DEFINE_CLASS_QUERY(type)                           \
   bool is_##type() const {                                   \
     return ((_class_id & ClassMask_##type) == Class_##type); \
   }                                                          \
   type##Node *as_##type() const {                            \
     assert(is_##type(), "invalid node class");               \
     return (type##Node*)this;                                \
   }                                                          \
   type##Node* isa_##type() const {                           \
     return (is_##type()) ? as_##type() : NULL;               \
   }
   DEFINE_CLASS_QUERY(AbstractLock)
   DEFINE_CLASS_QUERY(Add)
   DEFINE_CLASS_QUERY(AddP)
   DEFINE_CLASS_QUERY(Allocate)
   DEFINE_CLASS_QUERY(AllocateArray)
   DEFINE_CLASS_QUERY(Bool)
   DEFINE_CLASS_QUERY(BoxLock)
   DEFINE_CLASS_QUERY(Call)
   DEFINE_CLASS_QUERY(CallDynamicJava)
   DEFINE_CLASS_QUERY(CallJava)
   DEFINE_CLASS_QUERY(CallLeaf)
   DEFINE_CLASS_QUERY(CallRuntime)
   DEFINE_CLASS_QUERY(CallStaticJava)
   DEFINE_CLASS_QUERY(Catch)
   DEFINE_CLASS_QUERY(CatchProj)
   DEFINE_CLASS_QUERY(CheckCastPP)
   DEFINE_CLASS_QUERY(CastII)
   DEFINE_CLASS_QUERY(ConstraintCast)
   DEFINE_CLASS_QUERY(ClearArray)
   DEFINE_CLASS_QUERY(CMove)
   DEFINE_CLASS_QUERY(Cmp)
   DEFINE_CLASS_QUERY(CountedLoop)
   DEFINE_CLASS_QUERY(CountedLoopEnd)
   DEFINE_CLASS_QUERY(DecodeNarrowPtr)
   DEFINE_CLASS_QUERY(DecodeN)
   DEFINE_CLASS_QUERY(DecodeNKlass)
   DEFINE_CLASS_QUERY(EncodeNarrowPtr)
   DEFINE_CLASS_QUERY(EncodeP)
   DEFINE_CLASS_QUERY(EncodePKlass)
   DEFINE_CLASS_QUERY(FastLock)
   DEFINE_CLASS_QUERY(FastUnlock)
   DEFINE_CLASS_QUERY(If)
   DEFINE_CLASS_QUERY(IfFalse)
   DEFINE_CLASS_QUERY(IfTrue)
   DEFINE_CLASS_QUERY(Initialize)
   DEFINE_CLASS_QUERY(Jump)
   DEFINE_CLASS_QUERY(JumpProj)
   DEFINE_CLASS_QUERY(Load)
   DEFINE_CLASS_QUERY(LoadStore)
   DEFINE_CLASS_QUERY(Lock)
   DEFINE_CLASS_QUERY(Loop)
   DEFINE_CLASS_QUERY(Mach)
   DEFINE_CLASS_QUERY(MachBranch)
   DEFINE_CLASS_QUERY(MachCall)
   DEFINE_CLASS_QUERY(MachCallDynamicJava)
   DEFINE_CLASS_QUERY(MachCallJava)
   DEFINE_CLASS_QUERY(MachCallLeaf)
   DEFINE_CLASS_QUERY(MachCallRuntime)
   DEFINE_CLASS_QUERY(MachCallStaticJava)
   DEFINE_CLASS_QUERY(MachConstantBase)
   DEFINE_CLASS_QUERY(MachConstant)
   DEFINE_CLASS_QUERY(MachGoto)
   DEFINE_CLASS_QUERY(MachIf)
   DEFINE_CLASS_QUERY(MachNullCheck)
   DEFINE_CLASS_QUERY(MachProj)
   DEFINE_CLASS_QUERY(MachReturn)
   DEFINE_CLASS_QUERY(MachSafePoint)
   DEFINE_CLASS_QUERY(MachSpillCopy)
   DEFINE_CLASS_QUERY(MachTemp)
   DEFINE_CLASS_QUERY(MachMerge)
   DEFINE_CLASS_QUERY(Mem)
   DEFINE_CLASS_QUERY(MemBar)
   DEFINE_CLASS_QUERY(MemBarStoreStore)
   DEFINE_CLASS_QUERY(MergeMem)
   DEFINE_CLASS_QUERY(Mul)
   DEFINE_CLASS_QUERY(Multi)
   DEFINE_CLASS_QUERY(MultiBranch)
   DEFINE_CLASS_QUERY(Parm)
   DEFINE_CLASS_QUERY(PCTable)
   DEFINE_CLASS_QUERY(Phi)
   DEFINE_CLASS_QUERY(Proj)
   DEFINE_CLASS_QUERY(Region)
   DEFINE_CLASS_QUERY(Root)
   DEFINE_CLASS_QUERY(SafePoint)
   DEFINE_CLASS_QUERY(SafePointScalarObject)
   DEFINE_CLASS_QUERY(Start)
   DEFINE_CLASS_QUERY(Store)
   DEFINE_CLASS_QUERY(Sub)
   DEFINE_CLASS_QUERY(Type)
   DEFINE_CLASS_QUERY(Vector)
   DEFINE_CLASS_QUERY(LoadVector)
   DEFINE_CLASS_QUERY(StoreVector)
   DEFINE_CLASS_QUERY(Unlock)
   #undef DEFINE_CLASS_QUERY
   // duplicate of is_MachSpillCopy()
   bool is_SpillCopy () const {
     return ((_class_id & ClassMask_MachSpillCopy) == Class_MachSpillCopy);
   }
   bool is_Con () const { return (_flags & Flag_is_Con) != 0; }
   // The data node which is safe to leave in dead loop during IGVN optimization.
   bool is_dead_loop_safe() const {
     return is_Phi() || (is_Proj() && in(0) == NULL) ||
            ((_flags & (Flag_is_dead_loop_safe | Flag_is_Con)) != 0 &&
             (!is_Proj() || !in(0)->is_Allocate()));
   }
   // is_Copy() returns copied edge index (0 or 1)
   uint is_Copy() const { return (_flags & Flag_is_Copy); }
   virtual bool is_CFG() const { return false; }
   // If this node is control-dependent on a test, can it be
   // rerouted to a dominating equivalent test?  This is usually
   // true of non-CFG nodes, but can be false for operations which
   // depend for their correct sequencing on more than one test.
   // (In that case, hoisting to a dominating test may silently
   // skip some other important test.)
   virtual bool depends_only_on_test() const { assert(!is_CFG(), ""); return true; };
   // When building basic blocks, I need to have a notion of block beginning
   // Nodes, next block selector Nodes (block enders), and next block
   // projections.  These calls need to work on their machine equivalents.  The
   // Ideal beginning Nodes are RootNode, RegionNode and StartNode.
   bool is_block_start() const {
     if ( is_Region() )
       return this == (const Node*)in(0);
     else
       return is_Start();
   }
   // The Ideal control projection Nodes are IfTrue/IfFalse, JumpProjNode, Root,
   // Goto and Return.  This call also returns the block ending Node.
   virtual const Node *is_block_proj() const;
   // The node is a "macro" node which needs to be expanded before matching
   bool is_macro() const { return (_flags & Flag_is_macro) != 0; }
   // The node is expensive: the best control is set during loop opts
   bool is_expensive() const { return (_flags & Flag_is_expensive) != 0 && in(0) != NULL; }
 //----------------- Optimization
   // Get the worst-case Type output for this Node.
   virtual const class Type *bottom_type() const;
   // If we find a better type for a node, try to record it permanently.
   // Return true if this node actually changed.
   // Be sure to do the hash_delete game in the "rehash" variant.
   void raise_bottom_type(const Type* new_type);
   // Get the address type with which this node uses and/or defs memory,
   // or NULL if none.  The address type is conservatively wide.
   // Returns non-null for calls, membars, loads, stores, etc.
   // Returns TypePtr::BOTTOM if the node touches memory "broadly".
   virtual const class TypePtr *adr_type() const { return NULL; }
   // Return an existing node which computes the same function as this node.
   // The optimistic combined algorithm requires this to return a Node which
   // is a small number of steps away (e.g., one of my inputs).
   virtual Node *Identity( PhaseTransform *phase );
   // Return the set of values this Node can take on at runtime.
   virtual const Type *Value( PhaseTransform *phase ) const;
   // Return a node which is more "ideal" than the current node.
   // The invariants on this call are subtle.  If in doubt, read the
   // treatise in node.cpp above the default implemention AND TEST WITH
   // +VerifyIterativeGVN!
   virtual Node *Ideal(PhaseGVN *phase, bool can_reshape);
   // Some nodes have specific Ideal subgraph transformations only if they are
   // unique users of specific nodes. Such nodes should be put on IGVN worklist
   // for the transformations to happen.
   bool has_special_unique_user() const;
   // Skip Proj and CatchProj nodes chains. Check for Null and Top.
   Node* find_exact_control(Node* ctrl);
   // Check if 'this' node dominates or equal to 'sub'.
   bool dominates(Node* sub, Node_List &nlist);
 protected:
   bool remove_dead_region(PhaseGVN *phase, bool can_reshape);
 public:
   // Idealize graph, using DU info.  Done after constant propagation
   virtual Node *Ideal_DU_postCCP( PhaseCCP *ccp );
   // See if there is valid pipeline info
   static  const Pipeline *pipeline_class();
   virtual const Pipeline *pipeline() const;
   // Compute the latency from the def to this instruction of the ith input node
   uint latency(uint i);
   // Hash & compare functions, for pessimistic value numbering
   // If the hash function returns the special sentinel value NO_HASH,
   // the node is guaranteed never to compare equal to any other node.
   // If we accidentally generate a hash with value NO_HASH the node
   // won't go into the table and we'll lose a little optimization.
   enum { NO_HASH = 0 };
   virtual uint hash() const;
   virtual uint cmp( const Node &n ) const;
   // Operation appears to be iteratively computed (such as an induction variable)
   // It is possible for this operation to return false for a loop-varying
   // value, if it appears (by local graph inspection) to be computed by a simple conditional.
   bool is_iteratively_computed();
   // Determine if a node is Counted loop induction variable.
   // The method is defined in loopnode.cpp.
   const Node* is_loop_iv() const;
   // Return a node with opcode "opc" and same inputs as "this" if one can
   // be found; Otherwise return NULL;
   Node* find_similar(int opc);
   // Return the unique control out if only one. Null if none or more than one.
   Node* unique_ctrl_out();
 //----------------- Code Generation
   // Ideal register class for Matching.  Zero means unmatched instruction
   // (these are cloned instead of converted to machine nodes).
   virtual uint ideal_reg() const;
   static const uint NotAMachineReg;   // must be > max. machine register
   // Do we Match on this edge index or not?  Generally false for Control
   // and true for everything else.  Weird for calls & returns.
   virtual uint match_edge(uint idx) const;
   // Register class output is returned in
   virtual const RegMask &out_RegMask() const;
   // Register class input is expected in
   virtual const RegMask &in_RegMask(uint) const;
   // Should we clone rather than spill this instruction?
   bool rematerialize() const;
   // Return JVM State Object if this Node carries debug info, or NULL otherwise
   virtual JVMState* jvms() const;
   // Print as assembly
   virtual void format( PhaseRegAlloc *, outputStream* st = tty ) const;
   // Emit bytes starting at parameter 'ptr'
   // Bump 'ptr' by the number of output bytes
   virtual void emit(CodeBuffer &cbuf, PhaseRegAlloc *ra_) const;
   // Size of instruction in bytes
   virtual uint size(PhaseRegAlloc *ra_) const;
   // Convenience function to extract an integer constant from a node.
   // If it is not an integer constant (either Con, CastII, or Mach),
   // return value_if_unknown.
   jint find_int_con(jint value_if_unknown) const {
     const TypeInt* t = find_int_type();
     return (t != NULL && t->is_con()) ? t->get_con() : value_if_unknown;
   }
   // Return the constant, knowing it is an integer constant already
   jint get_int() const {
     const TypeInt* t = find_int_type();
     guarantee(t != NULL, "must be con");
     return t->get_con();
   }
   // Here's where the work is done.  Can produce non-constant int types too.
   const TypeInt* find_int_type() const;
   // Same thing for long (and intptr_t, via type.hpp):
   jlong get_long() const {
     const TypeLong* t = find_long_type();
     guarantee(t != NULL, "must be con");
     return t->get_con();
   }
   jlong find_long_con(jint value_if_unknown) const {
     const TypeLong* t = find_long_type();
     return (t != NULL && t->is_con()) ? t->get_con() : value_if_unknown;
   }
   const TypeLong* find_long_type() const;
   const TypePtr* get_ptr_type() const;
   // These guys are called by code generated by ADLC:
   intptr_t get_ptr() const;
   intptr_t get_narrowcon() const;
   jdouble getd() const;
   jfloat getf() const;
   // Nodes which are pinned into basic blocks
   virtual bool pinned() const { return false; }
   // Nodes which use memory without consuming it, hence need antidependences
   // More specifically, needs_anti_dependence_check returns true iff the node
   // (a) does a load, and (b) does not perform a store (except perhaps to a
   // stack slot or some other unaliased location).
   bool needs_anti_dependence_check() const;
   // Return which operand this instruction may cisc-spill. In other words,
   // return operand position that can convert from reg to memory access
   virtual int cisc_operand() const { return AdlcVMDeps::Not_cisc_spillable; }
   bool is_cisc_alternate() const { return (_flags & Flag_is_cisc_alternate) != 0; }
 //----------------- Graph walking
 public:
   // Walk and apply member functions recursively.
   // Supplied (this) pointer is root.
   void walk(NFunc pre, NFunc post, void *env);
   static void nop(Node &, void*); // Dummy empty function
   static void packregion( Node &n, void* );
 private:
   void walk_(NFunc pre, NFunc post, void *env, VectorSet &visited);
 //----------------- Printing, etc
 public:
 #ifndef PRODUCT
   Node* find(int idx) const;         // Search the graph for the given idx.
   Node* find_ctrl(int idx) const;    // Search control ancestors for the given idx.
   void dump() const { dump("\n"); }  // Print this node.
   void dump(const char* suffix, outputStream *st = tty) const;// Print this node.
   void dump(int depth) const;        // Print this node, recursively to depth d
   void dump_ctrl(int depth) const;   // Print control nodes, to depth d
   virtual void dump_req(outputStream *st = tty) const;     // Print required-edge info
   virtual void dump_prec(outputStream *st = tty) const;    // Print precedence-edge info
   virtual void dump_out(outputStream *st = tty) const;     // Print the output edge info
   virtual void dump_spec(outputStream *st) const {}; // Print per-node info
   void verify_edges(Unique_Node_List &visited); // Verify bi-directional edges
   void verify() const;               // Check Def-Use info for my subgraph
   static void verify_recur(const Node *n, int verify_depth, VectorSet &old_space, VectorSet &new_space);
   // This call defines a class-unique string used to identify class instances
   virtual const char *Name() const;
   void dump_format(PhaseRegAlloc *ra) const; // debug access to MachNode::format(...)
   // RegMask Print Functions
   void dump_in_regmask(int idx) { in_RegMask(idx).dump(); }
   void dump_out_regmask() { out_RegMask().dump(); }
   static bool in_dump() { return Compile::current()->_in_dump_cnt > 0; }
   void fast_dump() const {
     tty->print("%4d: %-17s", _idx, Name());
     for (uint i = 0; i < len(); i++)
       if (in(i))
         tty->print(" %4d", in(i)->_idx);
       else
         tty->print(" NULL");
     tty->print("\n");
   }
 #endif
 #ifdef ASSERT
   void verify_construction();
   bool verify_jvms(const JVMState* jvms) const;
   int  _debug_idx;                     // Unique value assigned to every node.
   int   debug_idx() const              { return _debug_idx; }
   void  set_debug_idx( int debug_idx ) { _debug_idx = debug_idx; }
   Node* _debug_orig;                   // Original version of this, if any.
   Node*  debug_orig() const            { return _debug_orig; }
   void   set_debug_orig(Node* orig);   // _debug_orig = orig
   int        _hash_lock;               // Barrier to modifications of nodes in the hash table
   void  enter_hash_lock() { ++_hash_lock; assert(_hash_lock < 99, "in too many hash tables?"); }
   void   exit_hash_lock() { --_hash_lock; assert(_hash_lock >= 0, "mispaired hash locks"); }
   static void init_NodeProperty();
   #if OPTO_DU_ITERATOR_ASSERT
   const Node* _last_del;               // The last deleted node.
   uint        _del_tick;               // Bumped when a deletion happens..
   #endif
 #endif
 };
 //-----------------------------------------------------------------------------
 // Iterators over DU info, and associated Node functions.
 #if OPTO_DU_ITERATOR_ASSERT
 // Common code for assertion checking on DU iterators.
 class DUIterator_Common VALUE_OBJ_CLASS_SPEC {
 #ifdef ASSERT
  protected:
   bool         _vdui;               // cached value of VerifyDUIterators
   const Node*  _node;               // the node containing the _out array
   uint         _outcnt;             // cached node->_outcnt
   uint         _del_tick;           // cached node->_del_tick
   Node*        _last;               // last value produced by the iterator
   void sample(const Node* node);    // used by c'tor to set up for verifies
   void verify(const Node* node, bool at_end_ok = false);
   void verify_resync();
   void reset(const DUIterator_Common& that);
 // The VDUI_ONLY macro protects code conditionalized on VerifyDUIterators
   #define I_VDUI_ONLY(i,x) { if ((i)._vdui) { x; } }
 #else
   #define I_VDUI_ONLY(i,x) { }
 #endif //ASSERT
 };
 #define VDUI_ONLY(x)     I_VDUI_ONLY(*this, x)
 // Default DU iterator.  Allows appends onto the out array.
 // Allows deletion from the out array only at the current point.
 // Usage:
 //  for (DUIterator i = x->outs(); x->has_out(i); i++) {
 //    Node* y = x->out(i);
 //    ...
 //  }
 // Compiles in product mode to a unsigned integer index, which indexes
 // onto a repeatedly reloaded base pointer of x->_out.  The loop predicate
 // also reloads x->_outcnt.  If you delete, you must perform "--i" just
 // before continuing the loop.  You must delete only the last-produced
 // edge.  You must delete only a single copy of the last-produced edge,
 // or else you must delete all copies at once (the first time the edge
 // is produced by the iterator).
 class DUIterator : public DUIterator_Common {
   friend class Node;
   // This is the index which provides the product-mode behavior.
   // Whatever the product-mode version of the system does to the
   // DUI index is done to this index.  All other fields in
   // this class are used only for assertion checking.
   uint         _idx;
   #ifdef ASSERT
   uint         _refresh_tick;    // Records the refresh activity.
   void sample(const Node* node); // Initialize _refresh_tick etc.
   void verify(const Node* node, bool at_end_ok = false);
   void verify_increment();       // Verify an increment operation.
   void verify_resync();          // Verify that we can back up over a deletion.
   void verify_finish();          // Verify that the loop terminated properly.
   void refresh();                // Resample verification info.
   void reset(const DUIterator& that);  // Resample after assignment.
   #endif
   DUIterator(const Node* node, int dummy_to_avoid_conversion)
     { _idx = 0;                         debug_only(sample(node)); }
  public:
   // initialize to garbage; clear _vdui to disable asserts
   DUIterator()
     { /*initialize to garbage*/         debug_only(_vdui = false); }
   void operator++(int dummy_to_specify_postfix_op)
     { _idx++;                           VDUI_ONLY(verify_increment()); }
   void operator--()
     { VDUI_ONLY(verify_resync());       --_idx; }
   ~DUIterator()
     { VDUI_ONLY(verify_finish()); }
   void operator=(const DUIterator& that)
     { _idx = that._idx;                 debug_only(reset(that)); }
 };
 DUIterator Node::outs() const
   { return DUIterator(this, 0); }
 DUIterator& Node::refresh_out_pos(DUIterator& i) const
   { I_VDUI_ONLY(i, i.refresh());        return i; }
 bool Node::has_out(DUIterator& i) const
   { I_VDUI_ONLY(i, i.verify(this,true));return i._idx < _outcnt; }
 Node*    Node::out(DUIterator& i) const
   { I_VDUI_ONLY(i, i.verify(this));     return debug_only(i._last=) _out[i._idx]; }
 // Faster DU iterator.  Disallows insertions into the out array.
 // Allows deletion from the out array only at the current point.
 // Usage:
 //  for (DUIterator_Fast imax, i = x->fast_outs(imax); i < imax; i++) {
 //    Node* y = x->fast_out(i);
 //    ...
 //  }
 // Compiles in product mode to raw Node** pointer arithmetic, with
 // no reloading of pointers from the original node x.  If you delete,
 // you must perform "--i; --imax" just before continuing the loop.
 // If you delete multiple copies of the same edge, you must decrement
 // imax, but not i, multiple times:  "--i, imax -= num_edges".
 class DUIterator_Fast : public DUIterator_Common {
   friend class Node;
   friend class DUIterator_Last;
   // This is the pointer which provides the product-mode behavior.
   // Whatever the product-mode version of the system does to the
   // DUI pointer is done to this pointer.  All other fields in
   // this class are used only for assertion checking.
   Node**       _outp;
   #ifdef ASSERT
   void verify(const Node* node, bool at_end_ok = false);
   void verify_limit();
   void verify_resync();
   void verify_relimit(uint n);
   void reset(const DUIterator_Fast& that);
   #endif
   // Note:  offset must be signed, since -1 is sometimes passed
   DUIterator_Fast(const Node* node, ptrdiff_t offset)
     { _outp = node->_out + offset;      debug_only(sample(node)); }
  public:
   // initialize to garbage; clear _vdui to disable asserts
   DUIterator_Fast()
     { /*initialize to garbage*/         debug_only(_vdui = false); }
   void operator++(int dummy_to_specify_postfix_op)
     { _outp++;                          VDUI_ONLY(verify(_node, true)); }
   void operator--()
     { VDUI_ONLY(verify_resync());       --_outp; }
   void operator-=(uint n)   // applied to the limit only
     { _outp -= n;           VDUI_ONLY(verify_relimit(n));  }
   bool operator<(DUIterator_Fast& limit) {
     I_VDUI_ONLY(*this, this->verify(_node, true));
     I_VDUI_ONLY(limit, limit.verify_limit());
     return _outp < limit._outp;
   }
   void operator=(const DUIterator_Fast& that)
     { _outp = that._outp;               debug_only(reset(that)); }
 };
 DUIterator_Fast Node::fast_outs(DUIterator_Fast& imax) const {
   // Assign a limit pointer to the reference argument:
   imax = DUIterator_Fast(this, (ptrdiff_t)_outcnt);
   // Return the base pointer:
   return DUIterator_Fast(this, 0);
 }
 Node* Node::fast_out(DUIterator_Fast& i) const {
   I_VDUI_ONLY(i, i.verify(this));
   return debug_only(i._last=) *i._outp;
 }
 // Faster DU iterator.  Requires each successive edge to be removed.
 // Does not allow insertion of any edges.
 // Usage:
 //  for (DUIterator_Last imin, i = x->last_outs(imin); i >= imin; i -= num_edges) {
 //    Node* y = x->last_out(i);
 //    ...
 //  }
 // Compiles in product mode to raw Node** pointer arithmetic, with
 // no reloading of pointers from the original node x.
 class DUIterator_Last : private DUIterator_Fast {
   friend class Node;
   #ifdef ASSERT
   void verify(const Node* node, bool at_end_ok = false);
   void verify_limit();
   void verify_step(uint num_edges);
   #endif
   // Note:  offset must be signed, since -1 is sometimes passed
   DUIterator_Last(const Node* node, ptrdiff_t offset)
     : DUIterator_Fast(node, offset) { }
   void operator++(int dummy_to_specify_postfix_op) {} // do not use
   void operator<(int)                              {} // do not use
  public:
   DUIterator_Last() { }
   // initialize to garbage
   void operator--()
     { _outp--;              VDUI_ONLY(verify_step(1));  }
   void operator-=(uint n)
     { _outp -= n;           VDUI_ONLY(verify_step(n));  }
   bool operator>=(DUIterator_Last& limit) {
     I_VDUI_ONLY(*this, this->verify(_node, true));
     I_VDUI_ONLY(limit, limit.verify_limit());
     return _outp >= limit._outp;
   }
   void operator=(const DUIterator_Last& that)
     { DUIterator_Fast::operator=(that); }
 };
 DUIterator_Last Node::last_outs(DUIterator_Last& imin) const {
   // Assign a limit pointer to the reference argument:
   imin = DUIterator_Last(this, 0);
   // Return the initial pointer:
   return DUIterator_Last(this, (ptrdiff_t)_outcnt - 1);
 }
 Node* Node::last_out(DUIterator_Last& i) const {
   I_VDUI_ONLY(i, i.verify(this));
   return debug_only(i._last=) *i._outp;
 }
 #endif //OPTO_DU_ITERATOR_ASSERT
 #undef I_VDUI_ONLY
 #undef VDUI_ONLY
 // An Iterator that truly follows the iterator pattern.  Doesn't
 // support deletion but could be made to.
 //
 //   for (SimpleDUIterator i(n); i.has_next(); i.next()) {
 //     Node* m = i.get();
 //
 class SimpleDUIterator : public StackObj {
  private:
   Node* node;
   DUIterator_Fast i;
   DUIterator_Fast imax;
  public:
   SimpleDUIterator(Node* n): node(n), i(n->fast_outs(imax)) {}
   bool has_next() { return i < imax; }
   void next() { i++; }
   Node* get() { return node->fast_out(i); }
 };
 //-----------------------------------------------------------------------------
 // Map dense integer indices to Nodes.  Uses classic doubling-array trick.
 // Abstractly provides an infinite array of Node*'s, initialized to NULL.
 // Note that the constructor just zeros things, and since I use Arena
 // allocation I do not need a destructor to reclaim storage.
 class Node_Array : public ResourceObj {
   friend class VMStructs;
 protected:
   Arena *_a;                    // Arena to allocate in
   uint   _max;
   Node **_nodes;
   void   grow( uint i );        // Grow array node to fit
 public:
   Node_Array(Arena *a) : _a(a), _max(OptoNodeListSize) {
     _nodes = NEW_ARENA_ARRAY( a, Node *, OptoNodeListSize );
     for( int i = 0; i < OptoNodeListSize; i++ ) {
       _nodes[i] = NULL;
     }
   }
   Node_Array(Node_Array *na) : _a(na->_a), _max(na->_max), _nodes(na->_nodes) {}
   Node *operator[] ( uint i ) const // Lookup, or NULL for not mapped
   { return (i<_max) ? _nodes[i] : (Node*)NULL; }
   Node *at( uint i ) const { assert(i<_max,"oob"); return _nodes[i]; }
   Node **adr() { return _nodes; }
   // Extend the mapping: index i maps to Node *n.
   void map( uint i, Node *n ) { if( i>=_max ) grow(i); _nodes[i] = n; }
   void insert( uint i, Node *n );
   void remove( uint i );        // Remove, preserving order
   void sort( C_sort_func_t func);
   void reset( Arena *new_a );   // Zap mapping to empty; reclaim storage
   void clear();                 // Set all entries to NULL, keep storage
   uint Size() const { return _max; }
   void dump() const;
 };
 class Node_List : public Node_Array {
   friend class VMStructs;
   uint _cnt;
 public:
   Node_List() : Node_Array(Thread::current()->resource_area()), _cnt(0) {}
   Node_List(Arena *a) : Node_Array(a), _cnt(0) {}
   bool contains(const Node* n) const {
     for (uint e = 0; e < size(); e++) {
       if (at(e) == n) return true;
     }
     return false;
   }
   void insert( uint i, Node *n ) { Node_Array::insert(i,n); _cnt++; }
   void remove( uint i ) { Node_Array::remove(i); _cnt--; }
   void push( Node *b ) { map(_cnt++,b); }
   void yank( Node *n );         // Find and remove
   Node *pop() { return _nodes[--_cnt]; }
   Node *rpop() { Node *b = _nodes[0]; _nodes[0]=_nodes[--_cnt]; return b;}
   void clear() { _cnt = 0; Node_Array::clear(); } // retain storage
   uint size() const { return _cnt; }
   void dump() const;
   void dump_simple() const;
 };
 //------------------------------Unique_Node_List-------------------------------
 class Unique_Node_List : public Node_List {
   friend class VMStructs;
   VectorSet _in_worklist;
   uint _clock_index;            // Index in list where to pop from next
 public:
   Unique_Node_List() : Node_List(), _in_worklist(Thread::current()->resource_area()), _clock_index(0) {}
   Unique_Node_List(Arena *a) : Node_List(a), _in_worklist(a), _clock_index(0) {}
   void remove( Node *n );
   bool member( Node *n ) { return _in_worklist.test(n->_idx) != 0; }
   VectorSet &member_set(){ return _in_worklist; }
   void push( Node *b ) {
     if( !_in_worklist.test_set(b->_idx) )
       Node_List::push(b);
   }
   Node *pop() {
     if( _clock_index >= size() ) _clock_index = 0;
     Node *b = at(_clock_index);
     map( _clock_index, Node_List::pop());
     if (size() != 0) _clock_index++; // Always start from 0
     _in_worklist >>= b->_idx;
     return b;
   }
   Node *remove( uint i ) {
     Node *b = Node_List::at(i);
     _in_worklist >>= b->_idx;
     map(i,Node_List::pop());
     return b;
   }
   void yank( Node *n ) { _in_worklist >>= n->_idx; Node_List::yank(n); }
   void  clear() {
     _in_worklist.Clear();        // Discards storage but grows automatically
     Node_List::clear();
     _clock_index = 0;
   }
   // Used after parsing to remove useless nodes before Iterative GVN
   void remove_useless_nodes(VectorSet &useful);
 #ifndef PRODUCT
   void print_set() const { _in_worklist.print(); }
 #endif
 };
 // Inline definition of Compile::record_for_igvn must be deferred to this point.
 inline void Compile::record_for_igvn(Node* n) {
   _for_igvn->push(n);
 }
 //------------------------------Node_Stack-------------------------------------
 class Node_Stack {
   friend class VMStructs;
 protected:
   struct INode {
     Node *node; // Processed node
     uint  indx; // Index of next node's child
   };
   INode *_inode_top; // tos, stack grows up
   INode *_inode_max; // End of _inodes == _inodes + _max
   INode *_inodes;    // Array storage for the stack
   Arena *_a;         // Arena to allocate in
   void grow();
 public:
   Node_Stack(int size) {
     size_t max = (size > OptoNodeListSize) ? size : OptoNodeListSize;
     _a = Thread::current()->resource_area();
     _inodes = NEW_ARENA_ARRAY( _a, INode, max );
     _inode_max = _inodes + max;
     _inode_top = _inodes - 1; // stack is empty
   }
   Node_Stack(Arena *a, int size) : _a(a) {
     size_t max = (size > OptoNodeListSize) ? size : OptoNodeListSize;
     _inodes = NEW_ARENA_ARRAY( _a, INode, max );
     _inode_max = _inodes + max;
     _inode_top = _inodes - 1; // stack is empty
   }
   void pop() {
     assert(_inode_top >= _inodes, "node stack underflow");
     --_inode_top;
   }
   void push(Node *n, uint i) {
     ++_inode_top;
     if (_inode_top >= _inode_max) grow();
     INode *top = _inode_top; // optimization
     top->node = n;
     top->indx = i;
   }
   Node *node() const {
     return _inode_top->node;
   }
   Node* node_at(uint i) const {
     assert(_inodes + i <= _inode_top, "in range");
     return _inodes[i].node;
   }
   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;
   }
   void set_index(uint i) {
     _inode_top->indx = i;
   }
   uint size_max() const { return (uint)pointer_delta(_inode_max, _inodes,  sizeof(INode)); } // Max size
   uint size() const { return (uint)pointer_delta((_inode_top+1), _inodes,  sizeof(INode)); } // Current size
   bool is_nonempty() const { return (_inode_top >= _inodes); }
   bool is_empty() const { return (_inode_top < _inodes); }
   void clear() { _inode_top = _inodes - 1; } // retain storage
   // Node_Stack is used to map nodes.
   Node* find(uint idx) const;
 };
 //-----------------------------Node_Notes--------------------------------------
 // Debugging or profiling annotations loosely and sparsely associated
 // with some nodes.  See Compile::node_notes_at for the accessor.
 class Node_Notes VALUE_OBJ_CLASS_SPEC {
   friend class VMStructs;
   JVMState* _jvms;
 public:
   Node_Notes(JVMState* jvms = NULL) {
     _jvms = jvms;
   }
   JVMState* jvms()            { return _jvms; }
   void  set_jvms(JVMState* x) {        _jvms = x; }
   // True if there is nothing here.
   bool is_clear() {
     return (_jvms == NULL);
   }
   // Make there be nothing here.
   void clear() {
     _jvms = NULL;
   }
   // Make a new, clean node notes.
   static Node_Notes* make(Compile* C) {
     Node_Notes* nn = NEW_ARENA_ARRAY(C->comp_arena(), Node_Notes, 1);
     nn->clear();
     return nn;
   }
   Node_Notes* clone(Compile* C) {
     Node_Notes* nn = NEW_ARENA_ARRAY(C->comp_arena(), Node_Notes, 1);
     (*nn) = (*this);
     return nn;
   }
   // Absorb any information from source.
   bool update_from(Node_Notes* source) {
     bool changed = false;
     if (source != NULL) {
       if (source->jvms() != NULL) {
         set_jvms(source->jvms());
         changed = true;
       }
     }
     return changed;
   }
 };
 // Inlined accessors for Compile::node_nodes that require the preceding class:
 inline Node_Notes*
 Compile::locate_node_notes(GrowableArray<Node_Notes*>* arr,
                            int idx, bool can_grow) {
   assert(idx >= 0, "oob");
   int block_idx = (idx >> _log2_node_notes_block_size);
   int grow_by = (block_idx - (arr == NULL? 0: arr->length()));
   if (grow_by >= 0) {
     if (!can_grow)  return NULL;
     grow_node_notes(arr, grow_by + 1);
   }
   // (Every element of arr is a sub-array of length _node_notes_block_size.)
   return arr->at(block_idx) + (idx & (_node_notes_block_size-1));
 }
 inline bool
 Compile::set_node_notes_at(int idx, Node_Notes* value) {
   if (value == NULL || value->is_clear())
     return false;  // nothing to write => write nothing
   Node_Notes* loc = locate_node_notes(_node_note_array, idx, true);
   assert(loc != NULL, "");
   return loc->update_from(value);
 }
 //------------------------------TypeNode---------------------------------------
 // Node with a Type constant.
 class TypeNode : public Node {
 protected:
   virtual uint hash() const;    // Check the type
   virtual uint cmp( const Node &n ) const;
   virtual uint size_of() const; // Size is bigger
   const Type* const _type;
 public:
   void set_type(const Type* t) {
     assert(t != NULL, "sanity");
     debug_only(uint check_hash = (VerifyHashTableKeys && _hash_lock) ? hash() : NO_HASH);
     *(const Type**)&_type = t;   // cast away const-ness
     // If this node is in the hash table, make sure it doesn't need a rehash.
     assert(check_hash == NO_HASH || check_hash == hash(), "type change must preserve hash code");
   }
   const Type* type() const { assert(_type != NULL, "sanity"); return _type; };
   TypeNode( const Type *t, uint required ) : Node(required), _type(t) {
     init_class_id(Class_Type);
   }
   virtual const Type *Value( PhaseTransform *phase ) const;
   virtual const Type *bottom_type() const;
   virtual       uint  ideal_reg() const;
 #ifndef PRODUCT
   virtual void dump_spec(outputStream *st) const;
 #endif
 };
 #endif // SHARE_VM_OPTO_NODE_HPP

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/opto/node.hpp@97d09139b360 (annotated)

src/share/vm/opto/node.hpp