c1_ValueMap.hpp revision 1472:c18cbe5936b8
1/* 2 * Copyright (c) 1999, 2008, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25class ValueMapEntry: public CompilationResourceObj { 26 private: 27 intx _hash; 28 Value _value; 29 int _nesting; 30 ValueMapEntry* _next; 31 32 public: 33 ValueMapEntry(intx hash, Value value, int nesting, ValueMapEntry* next) 34 : _hash(hash) 35 , _value(value) 36 , _nesting(nesting) 37 , _next(next) 38 { 39 } 40 41 intx hash() { return _hash; } 42 Value value() { return _value; } 43 int nesting() { return _nesting; } 44 ValueMapEntry* next() { return _next; } 45 46 void set_next(ValueMapEntry* next) { _next = next; } 47}; 48 49define_array(ValueMapEntryArray, ValueMapEntry*) 50define_stack(ValueMapEntryList, ValueMapEntryArray) 51 52// ValueMap implements nested hash tables for value numbering. It 53// maintains a set _killed_values which represents the instructions 54// which have been killed so far and an array of linked lists of 55// ValueMapEntries names _entries. Each ValueMapEntry has a nesting 56// which indicates what ValueMap nesting it belongs to. Higher 57// nesting values are always before lower values in the linked list. 58// This allows cloning of parent ValueMaps by simply copying the heads 59// of the list. _entry_count represents the number of reachable 60// entries in the ValueMap. A ValueMap is only allowed to mutate 61// ValueMapEntries with the same nesting level. Adding or removing 62// entries at the current nesting level requires updating 63// _entry_count. Elements in the parent's list that get killed can be 64// skipped if they are at the head of the list by simply moving to the 65// next element in the list and decrementing _entry_count. 66 67class ValueMap: public CompilationResourceObj { 68 private: 69 int _nesting; 70 ValueMapEntryArray _entries; 71 ValueSet _killed_values; 72 int _entry_count; 73 74 int nesting() { return _nesting; } 75 bool is_local_value_numbering() { return _nesting == 0; } 76 bool is_global_value_numbering() { return _nesting > 0; } 77 78 int entry_count() { return _entry_count; } 79 int size() { return _entries.length(); } 80 ValueMapEntry* entry_at(int i) { return _entries.at(i); } 81 82 // calculates the index of a hash value in a hash table of size n 83 int entry_index(intx hash, int n) { return (unsigned int)hash % n; } 84 85 // if entry_count > size_threshold, the size of the hash table is increased 86 int size_threshold() { return size(); } 87 88 // management of the killed-bitset for global value numbering 89 void kill_value(Value v) { if (is_global_value_numbering()) _killed_values.put(v); } 90 bool is_killed(Value v) { if (is_global_value_numbering()) return _killed_values.contains(v); else return false; } 91 92 // helper functions 93 void increase_table_size(); 94 95#ifndef PRODUCT 96 static int _number_of_finds; 97 static int _number_of_hits; 98 static int _number_of_kills; 99#endif // PRODUCT 100 101 public: 102 // creation 103 ValueMap(); // empty value map 104 ValueMap(ValueMap* old); // value map with increased nesting 105 106 // manipulation 107 Value find_insert(Value x); 108 109 void kill_memory(); 110 void kill_field(ciField* field); 111 void kill_array(ValueType* type); 112 void kill_exception(); 113 void kill_map(ValueMap* map); 114 void kill_all(); 115 116#ifndef PRODUCT 117 // debugging/printing 118 void print(); 119 120 static void reset_statistics(); 121 static void print_statistics(); 122#endif 123}; 124 125define_array(ValueMapArray, ValueMap*) 126 127 128class ValueNumberingVisitor: public InstructionVisitor { 129 protected: 130 // called by visitor functions for instructions that kill values 131 virtual void kill_memory() = 0; 132 virtual void kill_field(ciField* field) = 0; 133 virtual void kill_array(ValueType* type) = 0; 134 135 // visitor functions 136 void do_StoreField (StoreField* x) { 137 if (!x->is_initialized()) { 138 kill_memory(); 139 } else { 140 kill_field(x->field()); 141 } 142 } 143 void do_StoreIndexed (StoreIndexed* x) { kill_array(x->type()); } 144 void do_MonitorEnter (MonitorEnter* x) { kill_memory(); } 145 void do_MonitorExit (MonitorExit* x) { kill_memory(); } 146 void do_Invoke (Invoke* x) { kill_memory(); } 147 void do_UnsafePutRaw (UnsafePutRaw* x) { kill_memory(); } 148 void do_UnsafePutObject(UnsafePutObject* x) { kill_memory(); } 149 void do_Intrinsic (Intrinsic* x) { if (!x->preserves_state()) kill_memory(); } 150 151 void do_Phi (Phi* x) { /* nothing to do */ } 152 void do_Local (Local* x) { /* nothing to do */ } 153 void do_Constant (Constant* x) { /* nothing to do */ } 154 void do_LoadField (LoadField* x) { 155 if (!x->is_initialized()) { 156 kill_memory(); 157 } 158 } 159 void do_ArrayLength (ArrayLength* x) { /* nothing to do */ } 160 void do_LoadIndexed (LoadIndexed* x) { /* nothing to do */ } 161 void do_NegateOp (NegateOp* x) { /* nothing to do */ } 162 void do_ArithmeticOp (ArithmeticOp* x) { /* nothing to do */ } 163 void do_ShiftOp (ShiftOp* x) { /* nothing to do */ } 164 void do_LogicOp (LogicOp* x) { /* nothing to do */ } 165 void do_CompareOp (CompareOp* x) { /* nothing to do */ } 166 void do_IfOp (IfOp* x) { /* nothing to do */ } 167 void do_Convert (Convert* x) { /* nothing to do */ } 168 void do_NullCheck (NullCheck* x) { /* nothing to do */ } 169 void do_NewInstance (NewInstance* x) { /* nothing to do */ } 170 void do_NewTypeArray (NewTypeArray* x) { /* nothing to do */ } 171 void do_NewObjectArray (NewObjectArray* x) { /* nothing to do */ } 172 void do_NewMultiArray (NewMultiArray* x) { /* nothing to do */ } 173 void do_CheckCast (CheckCast* x) { /* nothing to do */ } 174 void do_InstanceOf (InstanceOf* x) { /* nothing to do */ } 175 void do_BlockBegin (BlockBegin* x) { /* nothing to do */ } 176 void do_Goto (Goto* x) { /* nothing to do */ } 177 void do_If (If* x) { /* nothing to do */ } 178 void do_IfInstanceOf (IfInstanceOf* x) { /* nothing to do */ } 179 void do_TableSwitch (TableSwitch* x) { /* nothing to do */ } 180 void do_LookupSwitch (LookupSwitch* x) { /* nothing to do */ } 181 void do_Return (Return* x) { /* nothing to do */ } 182 void do_Throw (Throw* x) { /* nothing to do */ } 183 void do_Base (Base* x) { /* nothing to do */ } 184 void do_OsrEntry (OsrEntry* x) { /* nothing to do */ } 185 void do_ExceptionObject(ExceptionObject* x) { /* nothing to do */ } 186 void do_RoundFP (RoundFP* x) { /* nothing to do */ } 187 void do_UnsafeGetRaw (UnsafeGetRaw* x) { /* nothing to do */ } 188 void do_UnsafeGetObject(UnsafeGetObject* x) { /* nothing to do */ } 189 void do_UnsafePrefetchRead (UnsafePrefetchRead* x) { /* nothing to do */ } 190 void do_UnsafePrefetchWrite(UnsafePrefetchWrite* x) { /* nothing to do */ } 191 void do_ProfileCall (ProfileCall* x) { /* nothing to do */ } 192 void do_ProfileCounter (ProfileCounter* x) { /* nothing to do */ } 193}; 194 195 196class ValueNumberingEffects: public ValueNumberingVisitor { 197 private: 198 ValueMap* _map; 199 200 public: 201 // implementation for abstract methods of ValueNumberingVisitor 202 void kill_memory() { _map->kill_memory(); } 203 void kill_field(ciField* field) { _map->kill_field(field); } 204 void kill_array(ValueType* type) { _map->kill_array(type); } 205 206 ValueNumberingEffects(ValueMap* map): _map(map) {} 207}; 208 209 210class GlobalValueNumbering: public ValueNumberingVisitor { 211 private: 212 ValueMap* _current_map; // value map of current block 213 ValueMapArray _value_maps; // list of value maps for all blocks 214 215 public: 216 // accessors 217 ValueMap* current_map() { return _current_map; } 218 ValueMap* value_map_of(BlockBegin* block) { return _value_maps.at(block->linear_scan_number()); } 219 void set_value_map_of(BlockBegin* block, ValueMap* map) { assert(value_map_of(block) == NULL, ""); _value_maps.at_put(block->linear_scan_number(), map); } 220 221 // implementation for abstract methods of ValueNumberingVisitor 222 void kill_memory() { current_map()->kill_memory(); } 223 void kill_field(ciField* field) { current_map()->kill_field(field); } 224 void kill_array(ValueType* type) { current_map()->kill_array(type); } 225 226 // main entry point that performs global value numbering 227 GlobalValueNumbering(IR* ir); 228}; 229