--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/src/share/vm/c1/c1_ValueMap.hpp Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,204 @@
+/*
+ * Copyright 1999-2006 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.
+ *
+ */
+
+class ValueMapEntry: public CompilationResourceObj {
+ private:
+ intx _hash;
+ Value _value;
+ int _nesting;
+ ValueMapEntry* _next;
+
+ public:
+ ValueMapEntry(intx hash, Value value, int nesting, ValueMapEntry* next)
+ : _hash(hash)
+ , _value(value)
+ , _nesting(nesting)
+ , _next(next)
+ {
+ }
+
+ intx hash() { return _hash; }
+ Value value() { return _value; }
+ int nesting() { return _nesting; }
+ ValueMapEntry* next() { return _next; }
+
+ void set_next(ValueMapEntry* next) { _next = next; }
+};
+
+define_array(ValueMapEntryArray, ValueMapEntry*)
+define_stack(ValueMapEntryList, ValueMapEntryArray)
+
+// ValueMap implements nested hash tables for value numbering. It
+// maintains a set _killed_values which represents the instructions
+// which have been killed so far and an array of linked lists of
+// ValueMapEntries names _entries. Each ValueMapEntry has a nesting
+// which indicates what ValueMap nesting it belongs to. Higher
+// nesting values are always before lower values in the linked list.
+// This allows cloning of parent ValueMaps by simply copying the heads
+// of the list. _entry_count represents the number of reachable
+// entries in the ValueMap. A ValueMap is only allowed to mutate
+// ValueMapEntries with the same nesting level. Adding or removing
+// entries at the current nesting level requires updating
+// _entry_count. Elements in the parent's list that get killed can be
+// skipped if they are at the head of the list by simply moving to the
+// next element in the list and decrementing _entry_count.
+
+class ValueMap: public CompilationResourceObj {
+ private:
+ int _nesting;
+ ValueMapEntryArray _entries;
+ ValueSet _killed_values;
+ int _entry_count;
+
+ int nesting() { return _nesting; }
+ bool is_local_value_numbering() { return _nesting == 0; }
+ bool is_global_value_numbering() { return _nesting > 0; }
+
+ int entry_count() { return _entry_count; }
+ int size() { return _entries.length(); }
+ ValueMapEntry* entry_at(int i) { return _entries.at(i); }
+
+ // calculates the index of a hash value in a hash table of size n
+ int entry_index(intx hash, int n) { return (unsigned int)hash % n; }
+
+ // if entry_count > size_threshold, the size of the hash table is increased
+ int size_threshold() { return size(); }
+
+ // management of the killed-bitset for global value numbering
+ void kill_value(Value v) { if (is_global_value_numbering()) _killed_values.put(v); }
+ bool is_killed(Value v) { if (is_global_value_numbering()) return _killed_values.contains(v); else return false; }
+
+ // helper functions
+ void increase_table_size();
+
+#ifndef PRODUCT
+ static int _number_of_finds;
+ static int _number_of_hits;
+ static int _number_of_kills;
+#endif // PRODUCT
+
+ public:
+ // creation
+ ValueMap(); // empty value map
+ ValueMap(ValueMap* old); // value map with increased nesting
+
+ // manipulation
+ Value find_insert(Value x);
+
+ void kill_memory();
+ void kill_field(ciField* field);
+ void kill_array(ValueType* type);
+ void kill_exception();
+ void kill_map(ValueMap* map);
+ void kill_all();
+
+#ifndef PRODUCT
+ // debugging/printing
+ void print();
+
+ static void reset_statistics();
+ static void print_statistics();
+#endif
+};
+
+define_array(ValueMapArray, ValueMap*)
+
+
+class ValueNumberingVisitor: public InstructionVisitor {
+ protected:
+ // called by visitor functions for instructions that kill values
+ virtual void kill_memory() = 0;
+ virtual void kill_field(ciField* field) = 0;
+ virtual void kill_array(ValueType* type) = 0;
+
+ // visitor functions
+ void do_StoreField (StoreField* x) { kill_field(x->field()); };
+ void do_StoreIndexed (StoreIndexed* x) { kill_array(x->type()); };
+ void do_MonitorEnter (MonitorEnter* x) { kill_memory(); };
+ void do_MonitorExit (MonitorExit* x) { kill_memory(); };
+ void do_Invoke (Invoke* x) { kill_memory(); };
+ void do_UnsafePutRaw (UnsafePutRaw* x) { kill_memory(); };
+ void do_UnsafePutObject(UnsafePutObject* x) { kill_memory(); };
+ void do_Intrinsic (Intrinsic* x) { if (!x->preserves_state()) kill_memory(); };
+
+ void do_Phi (Phi* x) { /* nothing to do */ };
+ void do_Local (Local* x) { /* nothing to do */ };
+ void do_Constant (Constant* x) { /* nothing to do */ };
+ void do_LoadField (LoadField* x) { /* nothing to do */ };
+ void do_ArrayLength (ArrayLength* x) { /* nothing to do */ };
+ void do_LoadIndexed (LoadIndexed* x) { /* nothing to do */ };
+ void do_NegateOp (NegateOp* x) { /* nothing to do */ };
+ void do_ArithmeticOp (ArithmeticOp* x) { /* nothing to do */ };
+ void do_ShiftOp (ShiftOp* x) { /* nothing to do */ };
+ void do_LogicOp (LogicOp* x) { /* nothing to do */ };
+ void do_CompareOp (CompareOp* x) { /* nothing to do */ };
+ void do_IfOp (IfOp* x) { /* nothing to do */ };
+ void do_Convert (Convert* x) { /* nothing to do */ };
+ void do_NullCheck (NullCheck* x) { /* nothing to do */ };
+ void do_NewInstance (NewInstance* x) { /* nothing to do */ };
+ void do_NewTypeArray (NewTypeArray* x) { /* nothing to do */ };
+ void do_NewObjectArray (NewObjectArray* x) { /* nothing to do */ };
+ void do_NewMultiArray (NewMultiArray* x) { /* nothing to do */ };
+ void do_CheckCast (CheckCast* x) { /* nothing to do */ };
+ void do_InstanceOf (InstanceOf* x) { /* nothing to do */ };
+ void do_BlockBegin (BlockBegin* x) { /* nothing to do */ };
+ void do_Goto (Goto* x) { /* nothing to do */ };
+ void do_If (If* x) { /* nothing to do */ };
+ void do_IfInstanceOf (IfInstanceOf* x) { /* nothing to do */ };
+ void do_TableSwitch (TableSwitch* x) { /* nothing to do */ };
+ void do_LookupSwitch (LookupSwitch* x) { /* nothing to do */ };
+ void do_Return (Return* x) { /* nothing to do */ };
+ void do_Throw (Throw* x) { /* nothing to do */ };
+ void do_Base (Base* x) { /* nothing to do */ };
+ void do_OsrEntry (OsrEntry* x) { /* nothing to do */ };
+ void do_ExceptionObject(ExceptionObject* x) { /* nothing to do */ };
+ void do_RoundFP (RoundFP* x) { /* nothing to do */ };
+ void do_UnsafeGetRaw (UnsafeGetRaw* x) { /* nothing to do */ };
+ void do_UnsafeGetObject(UnsafeGetObject* x) { /* nothing to do */ };
+ void do_UnsafePrefetchRead (UnsafePrefetchRead* x) { /* nothing to do */ };
+ void do_UnsafePrefetchWrite(UnsafePrefetchWrite* x) { /* nothing to do */ };
+ void do_ProfileCall (ProfileCall* x) { /* nothing to do */ };
+ void do_ProfileCounter (ProfileCounter* x) { /* nothing to do */ };
+};
+
+
+class GlobalValueNumbering: public ValueNumberingVisitor {
+ private:
+ ValueMap* _current_map; // value map of current block
+ ValueMapArray _value_maps; // list of value maps for all blocks
+
+ public:
+ // accessors
+ ValueMap* current_map() { return _current_map; }
+ ValueMap* value_map_of(BlockBegin* block) { return _value_maps.at(block->linear_scan_number()); }
+ void set_value_map_of(BlockBegin* block, ValueMap* map) { assert(value_map_of(block) == NULL, ""); _value_maps.at_put(block->linear_scan_number(), map); }
+
+ // implementation for abstract methods of ValueNumberingVisitor
+ void kill_memory() { current_map()->kill_memory(); }
+ void kill_field(ciField* field) { current_map()->kill_field(field); }
+ void kill_array(ValueType* type) { current_map()->kill_array(type); }
+
+ // main entry point that performs global value numbering
+ GlobalValueNumbering(IR* ir);
+};