c1_RangeCheckElimination.hpp revision 5776:de6a9e811145
1/* 2 * Copyright (c) 2012, 2013, 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 25#ifndef SHARE_VM_C1_C1_RANGECHECKELIMINATION_HPP 26#define SHARE_VM_C1_C1_RANGECHECKELIMINATION_HPP 27 28#include "c1/c1_Instruction.hpp" 29 30// Base class for range check elimination 31class RangeCheckElimination : AllStatic { 32public: 33 static void eliminate(IR *ir); 34}; 35 36// Implementation 37class RangeCheckEliminator VALUE_OBJ_CLASS_SPEC { 38private: 39 int _number_of_instructions; 40 bool _optimistic; // Insert predicates and deoptimize when they fail 41 IR *_ir; 42 43 define_array(BlockBeginArray, BlockBegin*) 44 define_stack(BlockBeginList, BlockBeginArray) 45 define_stack(IntegerStack, intArray) 46 define_array(IntegerMap, IntegerStack*) 47 48 class Verification : public _ValueObj /*VALUE_OBJ_CLASS_SPEC*/, public BlockClosure { 49 private: 50 IR *_ir; 51 boolArray _used; 52 BlockBeginList _current; 53 BlockBeginList _successors; 54 55 public: 56 Verification(IR *ir); 57 virtual void block_do(BlockBegin *block); 58 bool can_reach(BlockBegin *start, BlockBegin *end, BlockBegin *dont_use = NULL); 59 bool dominates(BlockBegin *dominator, BlockBegin *block); 60 }; 61 62public: 63 // Bounds for an instruction in the form x + c which c integer 64 // constant and x another instruction 65 class Bound : public CompilationResourceObj { 66 private: 67 int _upper; 68 Value _upper_instr; 69 int _lower; 70 Value _lower_instr; 71 72 public: 73 Bound(); 74 Bound(Value v); 75 Bound(Instruction::Condition cond, Value v, int constant = 0); 76 Bound(int lower, Value lower_instr, int upper, Value upper_instr); 77 ~Bound(); 78 79#ifdef ASSERT 80 void add_assertion(Instruction *instruction, Instruction *position, int i, Value instr, Instruction::Condition cond); 81#endif 82 int upper(); 83 Value upper_instr(); 84 int lower(); 85 Value lower_instr(); 86 void print(); 87 bool check_no_overflow(int const_value); 88 void or_op(Bound *b); 89 void and_op(Bound *b); 90 bool has_upper(); 91 bool has_lower(); 92 void set_upper(int upper, Value upper_instr); 93 void set_lower(int lower, Value lower_instr); 94 bool is_smaller(Bound *b); 95 void remove_upper(); 96 void remove_lower(); 97 void add_constant(int value); 98 Bound *copy(); 99 100 private: 101 void init(); 102 }; 103 104 105 class Visitor : public InstructionVisitor { 106 private: 107 Bound *_bound; 108 RangeCheckEliminator *_rce; 109 110 public: 111 void set_range_check_eliminator(RangeCheckEliminator *rce) { _rce = rce; } 112 Bound *bound() const { return _bound; } 113 void clear_bound() { _bound = NULL; } 114 115 protected: 116 // visitor functions 117 void do_Constant (Constant* x); 118 void do_IfOp (IfOp* x); 119 void do_LogicOp (LogicOp* x); 120 void do_ArithmeticOp (ArithmeticOp* x); 121 void do_Phi (Phi* x); 122 123 void do_StoreField (StoreField* x) { /* nothing to do */ }; 124 void do_StoreIndexed (StoreIndexed* x) { /* nothing to do */ }; 125 void do_MonitorEnter (MonitorEnter* x) { /* nothing to do */ }; 126 void do_MonitorExit (MonitorExit* x) { /* nothing to do */ }; 127 void do_Invoke (Invoke* x) { /* nothing to do */ }; 128 void do_UnsafePutRaw (UnsafePutRaw* x) { /* nothing to do */ }; 129 void do_UnsafePutObject(UnsafePutObject* x) { /* nothing to do */ }; 130 void do_Intrinsic (Intrinsic* x) { /* nothing to do */ }; 131 void do_Local (Local* x) { /* nothing to do */ }; 132 void do_LoadField (LoadField* x) { /* nothing to do */ }; 133 void do_ArrayLength (ArrayLength* x) { /* nothing to do */ }; 134 void do_LoadIndexed (LoadIndexed* x) { /* nothing to do */ }; 135 void do_NegateOp (NegateOp* x) { /* nothing to do */ }; 136 void do_ShiftOp (ShiftOp* x) { /* nothing to do */ }; 137 void do_CompareOp (CompareOp* x) { /* nothing to do */ }; 138 void do_Convert (Convert* x) { /* nothing to do */ }; 139 void do_NullCheck (NullCheck* x) { /* nothing to do */ }; 140 void do_TypeCast (TypeCast* x) { /* nothing to do */ }; 141 void do_NewInstance (NewInstance* x) { /* nothing to do */ }; 142 void do_NewTypeArray (NewTypeArray* x) { /* nothing to do */ }; 143 void do_NewObjectArray (NewObjectArray* x) { /* nothing to do */ }; 144 void do_NewMultiArray (NewMultiArray* x) { /* nothing to do */ }; 145 void do_CheckCast (CheckCast* x) { /* nothing to do */ }; 146 void do_InstanceOf (InstanceOf* x) { /* nothing to do */ }; 147 void do_BlockBegin (BlockBegin* x) { /* nothing to do */ }; 148 void do_Goto (Goto* x) { /* nothing to do */ }; 149 void do_If (If* x) { /* nothing to do */ }; 150 void do_IfInstanceOf (IfInstanceOf* x) { /* nothing to do */ }; 151 void do_TableSwitch (TableSwitch* x) { /* nothing to do */ }; 152 void do_LookupSwitch (LookupSwitch* x) { /* nothing to do */ }; 153 void do_Return (Return* x) { /* nothing to do */ }; 154 void do_Throw (Throw* x) { /* nothing to do */ }; 155 void do_Base (Base* x) { /* nothing to do */ }; 156 void do_OsrEntry (OsrEntry* x) { /* nothing to do */ }; 157 void do_ExceptionObject(ExceptionObject* x) { /* nothing to do */ }; 158 void do_RoundFP (RoundFP* x) { /* nothing to do */ }; 159 void do_UnsafeGetRaw (UnsafeGetRaw* x) { /* nothing to do */ }; 160 void do_UnsafeGetObject(UnsafeGetObject* x) { /* nothing to do */ }; 161 void do_UnsafeGetAndSetObject(UnsafeGetAndSetObject* x) { /* nothing to do */ }; 162 void do_UnsafePrefetchRead (UnsafePrefetchRead* x) { /* nothing to do */ }; 163 void do_UnsafePrefetchWrite(UnsafePrefetchWrite* x) { /* nothing to do */ }; 164 void do_ProfileCall (ProfileCall* x) { /* nothing to do */ }; 165 void do_ProfileReturnType (ProfileReturnType* x) { /* nothing to do */ }; 166 void do_ProfileInvoke (ProfileInvoke* x) { /* nothing to do */ }; 167 void do_RuntimeCall (RuntimeCall* x) { /* nothing to do */ }; 168 void do_MemBar (MemBar* x) { /* nothing to do */ }; 169 void do_RangeCheckPredicate(RangeCheckPredicate* x) { /* nothing to do */ }; 170#ifdef ASSERT 171 void do_Assert (Assert* x) { /* nothing to do */ }; 172#endif 173 }; 174 175#ifdef ASSERT 176 void add_assertions(Bound *bound, Instruction *instruction, Instruction *position); 177#endif 178 179 define_array(BoundArray, Bound *) 180 define_stack(BoundStack, BoundArray) 181 define_array(BoundMap, BoundStack *) 182 define_array(AccessIndexedArray, AccessIndexed *) 183 define_stack(AccessIndexedList, AccessIndexedArray) 184 define_array(InstructionArray, Instruction *) 185 define_stack(InstructionList, InstructionArray) 186 187 class AccessIndexedInfo : public CompilationResourceObj { 188 public: 189 AccessIndexedList *_list; 190 int _min; 191 int _max; 192 }; 193 194 define_array(AccessIndexedInfoArray, AccessIndexedInfo *) 195 BoundMap _bounds; // Mapping from Instruction's id to current bound 196 AccessIndexedInfoArray _access_indexed_info; // Mapping from Instruction's id to AccessIndexedInfo for in block motion 197 Visitor _visitor; 198 199public: 200 RangeCheckEliminator(IR *ir); 201 202 IR *ir() const { return _ir; } 203 204 // Pass over the dominator tree to identify blocks where there's an oppportunity for optimization 205 bool set_process_block_flags(BlockBegin *block); 206 // The core of the optimization work: pass over the dominator tree 207 // to propagate bound information, insert predicate out of loops, 208 // eliminate bound checks when possible and perform in block motion 209 void calc_bounds(BlockBegin *block, BlockBegin *loop_header); 210 // reorder bound checks within a block in order to eliminate some of them 211 void in_block_motion(BlockBegin *block, AccessIndexedList &accessIndexed, InstructionList &arrays); 212 213 // update/access current bound 214 void update_bound(IntegerStack &pushed, Value v, Instruction::Condition cond, Value value, int constant); 215 void update_bound(IntegerStack &pushed, Value v, Bound *bound); 216 Bound *get_bound(Value v); 217 218 bool loop_invariant(BlockBegin *loop_header, Instruction *instruction); // check for loop invariance 219 void add_access_indexed_info(InstructionList &indices, int i, Value instruction, AccessIndexed *ai); // record indexed access for in block motion 220 void remove_range_check(AccessIndexed *ai); // Mark this instructions as not needing a range check 221 void add_if_condition(IntegerStack &pushed, Value x, Value y, Instruction::Condition condition); // Update bound for an If 222 bool in_array_bound(Bound *bound, Value array); // Check whether bound is known to fall within array 223 224 // helper functions to work with predicates 225 Instruction* insert_after(Instruction* insert_position, Instruction* instr, int bci); 226 Instruction* predicate(Instruction* left, Instruction::Condition cond, Instruction* right, ValueStack* state, Instruction *insert_position, int bci=-1); 227 Instruction* predicate_cmp_with_const(Instruction* instr, Instruction::Condition cond, int constant, ValueStack* state, Instruction *insert_position, int bci=1); 228 Instruction* predicate_add(Instruction* left, int left_const, Instruction::Condition cond, Instruction* right, ValueStack* state, Instruction *insert_position, int bci=-1); 229 Instruction* predicate_add_cmp_with_const(Instruction* left, int left_const, Instruction::Condition cond, int constant, ValueStack* state, Instruction *insert_position, int bci=-1); 230 231 void insert_deoptimization(ValueStack *state, Instruction *insert_position, Instruction *array_instr, // Add predicate 232 Instruction *length_instruction, Instruction *lower_instr, int lower, 233 Instruction *upper_instr, int upper, AccessIndexed *ai); 234 bool is_ok_for_deoptimization(Instruction *insert_position, Instruction *array_instr, // Can we safely add a predicate? 235 Instruction *length_instr, Instruction *lower_instr, 236 int lower, Instruction *upper_instr, int upper); 237 void process_if(IntegerStack &pushed, BlockBegin *block, If *cond); // process If Instruction 238 void process_access_indexed(BlockBegin *loop_header, BlockBegin *block, AccessIndexed *ai); // process indexed access 239 240 void dump_condition_stack(BlockBegin *cur_block); 241 static void print_statistics(); 242}; 243 244#endif // SHARE_VM_C1_C1_RANGECHECKELIMINATION_HPP 245