duke@435: /*
never@2486:  * Copyright (c) 1999, 2011, Oracle and/or its affiliates. All rights reserved.
duke@435:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@435:  *
duke@435:  * This code is free software; you can redistribute it and/or modify it
duke@435:  * under the terms of the GNU General Public License version 2 only, as
duke@435:  * published by the Free Software Foundation.
duke@435:  *
duke@435:  * This code is distributed in the hope that it will be useful, but WITHOUT
duke@435:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@435:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
duke@435:  * version 2 for more details (a copy is included in the LICENSE file that
duke@435:  * accompanied this code).
duke@435:  *
duke@435:  * You should have received a copy of the GNU General Public License version
duke@435:  * 2 along with this work; if not, write to the Free Software Foundation,
duke@435:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@435:  *
trims@1907:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
trims@1907:  * or visit www.oracle.com if you need additional information or have any
trims@1907:  * questions.
duke@435:  *
duke@435:  */
duke@435: 
stefank@2314: #ifndef SHARE_VM_C1_C1_VALUEMAP_HPP
stefank@2314: #define SHARE_VM_C1_C1_VALUEMAP_HPP
stefank@2314: 
stefank@2314: #include "c1/c1_Instruction.hpp"
stefank@2314: #include "c1/c1_ValueSet.hpp"
stefank@2314: #include "memory/allocation.hpp"
stefank@2314: 
duke@435: class ValueMapEntry: public CompilationResourceObj {
duke@435:  private:
duke@435:   intx           _hash;
duke@435:   Value          _value;
duke@435:   int            _nesting;
duke@435:   ValueMapEntry* _next;
duke@435: 
duke@435:  public:
duke@435:   ValueMapEntry(intx hash, Value value, int nesting, ValueMapEntry* next)
duke@435:     : _hash(hash)
duke@435:     , _value(value)
duke@435:     , _nesting(nesting)
duke@435:     , _next(next)
duke@435:   {
duke@435:   }
duke@435: 
duke@435:   intx           hash()      { return _hash; }
duke@435:   Value          value()     { return _value; }
duke@435:   int            nesting()   { return _nesting; }
duke@435:   ValueMapEntry* next()      { return _next; }
duke@435: 
duke@435:   void set_next(ValueMapEntry* next) { _next = next; }
duke@435: };
duke@435: 
duke@435: define_array(ValueMapEntryArray, ValueMapEntry*)
duke@435: define_stack(ValueMapEntryList, ValueMapEntryArray)
duke@435: 
duke@435: // ValueMap implements nested hash tables for value numbering.  It
duke@435: // maintains a set _killed_values which represents the instructions
duke@435: // which have been killed so far and an array of linked lists of
duke@435: // ValueMapEntries names _entries.  Each ValueMapEntry has a nesting
duke@435: // which indicates what ValueMap nesting it belongs to.  Higher
duke@435: // nesting values are always before lower values in the linked list.
duke@435: // This allows cloning of parent ValueMaps by simply copying the heads
duke@435: // of the list.  _entry_count represents the number of reachable
duke@435: // entries in the ValueMap.  A ValueMap is only allowed to mutate
duke@435: // ValueMapEntries with the same nesting level.  Adding or removing
duke@435: // entries at the current nesting level requires updating
duke@435: // _entry_count.  Elements in the parent's list that get killed can be
duke@435: // skipped if they are at the head of the list by simply moving to the
duke@435: // next element in the list and decrementing _entry_count.
duke@435: 
duke@435: class ValueMap: public CompilationResourceObj {
duke@435:  private:
duke@435:   int           _nesting;
duke@435:   ValueMapEntryArray _entries;
duke@435:   ValueSet      _killed_values;
duke@435:   int           _entry_count;
duke@435: 
duke@435:   int           nesting()                        { return _nesting; }
duke@435:   bool          is_local_value_numbering()       { return _nesting == 0; }
duke@435:   bool          is_global_value_numbering()      { return _nesting > 0; }
duke@435: 
duke@435:   int           entry_count()                    { return _entry_count; }
duke@435:   int           size()                           { return _entries.length(); }
duke@435:   ValueMapEntry* entry_at(int i)                 { return _entries.at(i); }
duke@435: 
duke@435:   // calculates the index of a hash value in a hash table of size n
duke@435:   int           entry_index(intx hash, int n)    { return (unsigned int)hash % n; }
duke@435: 
duke@435:   // if entry_count > size_threshold, the size of the hash table is increased
duke@435:   int           size_threshold()                 { return size(); }
duke@435: 
duke@435:   // management of the killed-bitset for global value numbering
duke@435:   void          kill_value(Value v)              { if (is_global_value_numbering()) _killed_values.put(v); }
duke@435:   bool          is_killed(Value v)               { if (is_global_value_numbering()) return _killed_values.contains(v); else return false; }
duke@435: 
duke@435:   // helper functions
duke@435:   void          increase_table_size();
duke@435: 
duke@435: #ifndef PRODUCT
duke@435:   static int _number_of_finds;
duke@435:   static int _number_of_hits;
duke@435:   static int _number_of_kills;
duke@435: #endif // PRODUCT
duke@435: 
duke@435:  public:
duke@435:   // creation
duke@435:   ValueMap();                // empty value map
duke@435:   ValueMap(ValueMap* old);   // value map with increased nesting
duke@435: 
duke@435:   // manipulation
duke@435:   Value find_insert(Value x);
duke@435: 
duke@435:   void kill_memory();
duke@435:   void kill_field(ciField* field);
duke@435:   void kill_array(ValueType* type);
duke@435:   void kill_exception();
duke@435:   void kill_map(ValueMap* map);
duke@435:   void kill_all();
duke@435: 
duke@435: #ifndef PRODUCT
duke@435:   // debugging/printing
duke@435:   void print();
duke@435: 
duke@435:   static void reset_statistics();
duke@435:   static void print_statistics();
duke@435: #endif
duke@435: };
duke@435: 
duke@435: define_array(ValueMapArray, ValueMap*)
duke@435: 
duke@435: 
duke@435: class ValueNumberingVisitor: public InstructionVisitor {
duke@435:  protected:
duke@435:   // called by visitor functions for instructions that kill values
duke@435:   virtual void kill_memory() = 0;
duke@435:   virtual void kill_field(ciField* field) = 0;
duke@435:   virtual void kill_array(ValueType* type) = 0;
duke@435: 
duke@435:   // visitor functions
never@894:   void do_StoreField     (StoreField*      x) {
never@894:     if (!x->is_initialized()) {
never@894:       kill_memory();
never@894:     } else {
never@894:       kill_field(x->field());
never@894:     }
never@894:   }
never@894:   void do_StoreIndexed   (StoreIndexed*    x) { kill_array(x->type()); }
never@894:   void do_MonitorEnter   (MonitorEnter*    x) { kill_memory(); }
never@894:   void do_MonitorExit    (MonitorExit*     x) { kill_memory(); }
never@894:   void do_Invoke         (Invoke*          x) { kill_memory(); }
never@894:   void do_UnsafePutRaw   (UnsafePutRaw*    x) { kill_memory(); }
never@894:   void do_UnsafePutObject(UnsafePutObject* x) { kill_memory(); }
never@894:   void do_Intrinsic      (Intrinsic*       x) { if (!x->preserves_state()) kill_memory(); }
duke@435: 
never@894:   void do_Phi            (Phi*             x) { /* nothing to do */ }
never@894:   void do_Local          (Local*           x) { /* nothing to do */ }
never@894:   void do_Constant       (Constant*        x) { /* nothing to do */ }
never@894:   void do_LoadField      (LoadField*       x) {
never@894:     if (!x->is_initialized()) {
never@894:       kill_memory();
never@894:     }
never@894:   }
never@894:   void do_ArrayLength    (ArrayLength*     x) { /* nothing to do */ }
never@894:   void do_LoadIndexed    (LoadIndexed*     x) { /* nothing to do */ }
never@894:   void do_NegateOp       (NegateOp*        x) { /* nothing to do */ }
never@894:   void do_ArithmeticOp   (ArithmeticOp*    x) { /* nothing to do */ }
never@894:   void do_ShiftOp        (ShiftOp*         x) { /* nothing to do */ }
never@894:   void do_LogicOp        (LogicOp*         x) { /* nothing to do */ }
never@894:   void do_CompareOp      (CompareOp*       x) { /* nothing to do */ }
never@894:   void do_IfOp           (IfOp*            x) { /* nothing to do */ }
never@894:   void do_Convert        (Convert*         x) { /* nothing to do */ }
never@894:   void do_NullCheck      (NullCheck*       x) { /* nothing to do */ }
never@894:   void do_NewInstance    (NewInstance*     x) { /* nothing to do */ }
never@894:   void do_NewTypeArray   (NewTypeArray*    x) { /* nothing to do */ }
never@894:   void do_NewObjectArray (NewObjectArray*  x) { /* nothing to do */ }
never@894:   void do_NewMultiArray  (NewMultiArray*   x) { /* nothing to do */ }
never@894:   void do_CheckCast      (CheckCast*       x) { /* nothing to do */ }
never@894:   void do_InstanceOf     (InstanceOf*      x) { /* nothing to do */ }
never@894:   void do_BlockBegin     (BlockBegin*      x) { /* nothing to do */ }
never@894:   void do_Goto           (Goto*            x) { /* nothing to do */ }
never@894:   void do_If             (If*              x) { /* nothing to do */ }
never@894:   void do_IfInstanceOf   (IfInstanceOf*    x) { /* nothing to do */ }
never@894:   void do_TableSwitch    (TableSwitch*     x) { /* nothing to do */ }
never@894:   void do_LookupSwitch   (LookupSwitch*    x) { /* nothing to do */ }
never@894:   void do_Return         (Return*          x) { /* nothing to do */ }
never@894:   void do_Throw          (Throw*           x) { /* nothing to do */ }
never@894:   void do_Base           (Base*            x) { /* nothing to do */ }
never@894:   void do_OsrEntry       (OsrEntry*        x) { /* nothing to do */ }
never@894:   void do_ExceptionObject(ExceptionObject* x) { /* nothing to do */ }
never@894:   void do_RoundFP        (RoundFP*         x) { /* nothing to do */ }
never@894:   void do_UnsafeGetRaw   (UnsafeGetRaw*    x) { /* nothing to do */ }
never@894:   void do_UnsafeGetObject(UnsafeGetObject* x) { /* nothing to do */ }
never@894:   void do_UnsafePrefetchRead (UnsafePrefetchRead*  x) { /* nothing to do */ }
never@894:   void do_UnsafePrefetchWrite(UnsafePrefetchWrite* x) { /* nothing to do */ }
never@894:   void do_ProfileCall    (ProfileCall*     x) { /* nothing to do */ }
never@2486:   void do_ProfileInvoke  (ProfileInvoke*   x) { /* nothing to do */ };
never@2486:   void do_RuntimeCall    (RuntimeCall*     x) { /* nothing to do */ };
never@894: };
never@894: 
never@894: 
never@894: class ValueNumberingEffects: public ValueNumberingVisitor {
never@894:  private:
never@894:   ValueMap*     _map;
never@894: 
never@894:  public:
never@894:   // implementation for abstract methods of ValueNumberingVisitor
never@894:   void          kill_memory()                    { _map->kill_memory(); }
never@894:   void          kill_field(ciField* field)       { _map->kill_field(field); }
never@894:   void          kill_array(ValueType* type)      { _map->kill_array(type); }
never@894: 
never@894:   ValueNumberingEffects(ValueMap* map): _map(map) {}
duke@435: };
duke@435: 
duke@435: 
duke@435: class GlobalValueNumbering: public ValueNumberingVisitor {
duke@435:  private:
duke@435:   ValueMap*     _current_map;     // value map of current block
duke@435:   ValueMapArray _value_maps;      // list of value maps for all blocks
duke@435: 
duke@435:  public:
duke@435:   // accessors
duke@435:   ValueMap*     current_map()                    { return _current_map; }
duke@435:   ValueMap*     value_map_of(BlockBegin* block)  { return _value_maps.at(block->linear_scan_number()); }
duke@435:   void          set_value_map_of(BlockBegin* block, ValueMap* map)   { assert(value_map_of(block) == NULL, ""); _value_maps.at_put(block->linear_scan_number(), map); }
duke@435: 
duke@435:   // implementation for abstract methods of ValueNumberingVisitor
duke@435:   void          kill_memory()                    { current_map()->kill_memory(); }
duke@435:   void          kill_field(ciField* field)       { current_map()->kill_field(field); }
duke@435:   void          kill_array(ValueType* type)      { current_map()->kill_array(type); }
duke@435: 
duke@435:   // main entry point that performs global value numbering
duke@435:   GlobalValueNumbering(IR* ir);
duke@435: };
stefank@2314: 
stefank@2314: #endif // SHARE_VM_C1_C1_VALUEMAP_HPP