1 /* 2 * Copyright (c) 2012, 2019, 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_C1_C1_RANGECHECKELIMINATION_HPP 26 #define SHARE_C1_C1_RANGECHECKELIMINATION_HPP 27 28 #include "c1/c1_Instruction.hpp" 29 30 // Base class for range check elimination 31 class RangeCheckElimination : AllStatic { 32 public: 33 static void eliminate(IR *ir); 34 }; 35 36 // Implementation 37 class RangeCheckEliminator { 38 private: 39 int _number_of_instructions; 40 bool _optimistic; // Insert predicates and deoptimize when they fail 41 IR *_ir; 42 43 typedef GrowableArray<BlockBegin*> BlockBeginList; 44 typedef GrowableArray<int> IntegerStack; 45 46 class Verification : public BlockClosure { 47 // RangeCheckEliminator::Verification should never get instatiated on the heap. 48 private: 49 void* operator new(size_t size) throw(); 50 void* operator new[](size_t size) throw(); operator delete(void * p)51 void operator delete(void* p) { ShouldNotReachHere(); } operator delete[](void * p)52 void operator delete[](void* p) { ShouldNotReachHere(); } 53 54 IR *_ir; 55 boolArray _used; 56 BlockBeginList _current; 57 BlockBeginList _successors; 58 59 public: 60 Verification(IR *ir); 61 virtual void block_do(BlockBegin *block); 62 bool can_reach(BlockBegin *start, BlockBegin *end, BlockBegin *dont_use = NULL); 63 bool dominates(BlockBegin *dominator, BlockBegin *block); 64 }; 65 66 public: 67 // Bounds for an instruction in the form x + c which c integer 68 // constant and x another instruction 69 class Bound : public CompilationResourceObj { 70 private: 71 int _upper; 72 Value _upper_instr; 73 int _lower; 74 Value _lower_instr; 75 76 public: 77 Bound(); 78 Bound(Value v); 79 Bound(Instruction::Condition cond, Value v, int constant = 0); 80 Bound(int lower, Value lower_instr, int upper, Value upper_instr); 81 ~Bound(); 82 83 #ifdef ASSERT 84 void add_assertion(Instruction *instruction, Instruction *position, int i, Value instr, Instruction::Condition cond); 85 #endif 86 int upper(); 87 Value upper_instr(); 88 int lower(); 89 Value lower_instr(); 90 void print(); 91 bool check_no_overflow(int const_value); 92 void or_op(Bound *b); 93 void and_op(Bound *b); 94 bool has_upper(); 95 bool has_lower(); 96 void set_upper(int upper, Value upper_instr); 97 void set_lower(int lower, Value lower_instr); 98 bool is_smaller(Bound *b); 99 void remove_upper(); 100 void remove_lower(); 101 void add_constant(int value); 102 Bound *copy(); 103 104 private: 105 void init(); 106 }; 107 108 109 class Visitor : public InstructionVisitor { 110 private: 111 Bound *_bound; 112 RangeCheckEliminator *_rce; 113 114 public: set_range_check_eliminator(RangeCheckEliminator * rce)115 void set_range_check_eliminator(RangeCheckEliminator *rce) { _rce = rce; } bound() const116 Bound *bound() const { return _bound; } clear_bound()117 void clear_bound() { _bound = NULL; } 118 119 protected: 120 // visitor functions 121 void do_Constant (Constant* x); 122 void do_IfOp (IfOp* x); 123 void do_LogicOp (LogicOp* x); 124 void do_ArithmeticOp (ArithmeticOp* x); 125 void do_Phi (Phi* x); 126 do_StoreField(StoreField * x)127 void do_StoreField (StoreField* x) { /* nothing to do */ }; do_StoreIndexed(StoreIndexed * x)128 void do_StoreIndexed (StoreIndexed* x) { /* nothing to do */ }; do_MonitorEnter(MonitorEnter * x)129 void do_MonitorEnter (MonitorEnter* x) { /* nothing to do */ }; do_MonitorExit(MonitorExit * x)130 void do_MonitorExit (MonitorExit* x) { /* nothing to do */ }; do_Invoke(Invoke * x)131 void do_Invoke (Invoke* x) { /* nothing to do */ }; do_UnsafePutRaw(UnsafePutRaw * x)132 void do_UnsafePutRaw (UnsafePutRaw* x) { /* nothing to do */ }; do_UnsafePutObject(UnsafePutObject * x)133 void do_UnsafePutObject(UnsafePutObject* x) { /* nothing to do */ }; do_Intrinsic(Intrinsic * x)134 void do_Intrinsic (Intrinsic* x) { /* nothing to do */ }; do_Local(Local * x)135 void do_Local (Local* x) { /* nothing to do */ }; do_LoadField(LoadField * x)136 void do_LoadField (LoadField* x) { /* nothing to do */ }; do_ArrayLength(ArrayLength * x)137 void do_ArrayLength (ArrayLength* x) { /* nothing to do */ }; do_LoadIndexed(LoadIndexed * x)138 void do_LoadIndexed (LoadIndexed* x) { /* nothing to do */ }; do_NegateOp(NegateOp * x)139 void do_NegateOp (NegateOp* x) { /* nothing to do */ }; do_ShiftOp(ShiftOp * x)140 void do_ShiftOp (ShiftOp* x) { /* nothing to do */ }; do_CompareOp(CompareOp * x)141 void do_CompareOp (CompareOp* x) { /* nothing to do */ }; do_Convert(Convert * x)142 void do_Convert (Convert* x) { /* nothing to do */ }; do_NullCheck(NullCheck * x)143 void do_NullCheck (NullCheck* x) { /* nothing to do */ }; do_TypeCast(TypeCast * x)144 void do_TypeCast (TypeCast* x) { /* nothing to do */ }; do_NewInstance(NewInstance * x)145 void do_NewInstance (NewInstance* x) { /* nothing to do */ }; do_NewTypeArray(NewTypeArray * x)146 void do_NewTypeArray (NewTypeArray* x) { /* nothing to do */ }; do_NewObjectArray(NewObjectArray * x)147 void do_NewObjectArray (NewObjectArray* x) { /* nothing to do */ }; do_NewMultiArray(NewMultiArray * x)148 void do_NewMultiArray (NewMultiArray* x) { /* nothing to do */ }; do_CheckCast(CheckCast * x)149 void do_CheckCast (CheckCast* x) { /* nothing to do */ }; do_InstanceOf(InstanceOf * x)150 void do_InstanceOf (InstanceOf* x) { /* nothing to do */ }; do_BlockBegin(BlockBegin * x)151 void do_BlockBegin (BlockBegin* x) { /* nothing to do */ }; do_Goto(Goto * x)152 void do_Goto (Goto* x) { /* nothing to do */ }; do_If(If * x)153 void do_If (If* x) { /* nothing to do */ }; do_IfInstanceOf(IfInstanceOf * x)154 void do_IfInstanceOf (IfInstanceOf* x) { /* nothing to do */ }; do_TableSwitch(TableSwitch * x)155 void do_TableSwitch (TableSwitch* x) { /* nothing to do */ }; do_LookupSwitch(LookupSwitch * x)156 void do_LookupSwitch (LookupSwitch* x) { /* nothing to do */ }; do_Return(Return * x)157 void do_Return (Return* x) { /* nothing to do */ }; do_Throw(Throw * x)158 void do_Throw (Throw* x) { /* nothing to do */ }; do_Base(Base * x)159 void do_Base (Base* x) { /* nothing to do */ }; do_OsrEntry(OsrEntry * x)160 void do_OsrEntry (OsrEntry* x) { /* nothing to do */ }; do_ExceptionObject(ExceptionObject * x)161 void do_ExceptionObject(ExceptionObject* x) { /* nothing to do */ }; do_RoundFP(RoundFP * x)162 void do_RoundFP (RoundFP* x) { /* nothing to do */ }; do_UnsafeGetRaw(UnsafeGetRaw * x)163 void do_UnsafeGetRaw (UnsafeGetRaw* x) { /* nothing to do */ }; do_UnsafeGetObject(UnsafeGetObject * x)164 void do_UnsafeGetObject(UnsafeGetObject* x) { /* nothing to do */ }; do_UnsafeGetAndSetObject(UnsafeGetAndSetObject * x)165 void do_UnsafeGetAndSetObject(UnsafeGetAndSetObject* x) { /* nothing to do */ }; do_ProfileCall(ProfileCall * x)166 void do_ProfileCall (ProfileCall* x) { /* nothing to do */ }; do_ProfileReturnType(ProfileReturnType * x)167 void do_ProfileReturnType (ProfileReturnType* x) { /* nothing to do */ }; do_ProfileInvoke(ProfileInvoke * x)168 void do_ProfileInvoke (ProfileInvoke* x) { /* nothing to do */ }; do_RuntimeCall(RuntimeCall * x)169 void do_RuntimeCall (RuntimeCall* x) { /* nothing to do */ }; do_MemBar(MemBar * x)170 void do_MemBar (MemBar* x) { /* nothing to do */ }; do_RangeCheckPredicate(RangeCheckPredicate * x)171 void do_RangeCheckPredicate(RangeCheckPredicate* x) { /* nothing to do */ }; 172 #ifdef ASSERT do_Assert(Assert * x)173 void do_Assert (Assert* x) { /* nothing to do */ }; 174 #endif 175 }; 176 177 #ifdef ASSERT 178 void add_assertions(Bound *bound, Instruction *instruction, Instruction *position); 179 #endif 180 181 typedef GrowableArray<Bound*> BoundStack; 182 typedef GrowableArray<BoundStack*> BoundMap; 183 typedef GrowableArray<AccessIndexed*> AccessIndexedList; 184 typedef GrowableArray<Instruction*> InstructionList; 185 186 class AccessIndexedInfo : public CompilationResourceObj { 187 public: 188 AccessIndexedList *_list; 189 int _min; 190 int _max; 191 }; 192 193 typedef GrowableArray<AccessIndexedInfo*> AccessIndexedInfoArray; 194 BoundMap _bounds; // Mapping from Instruction's id to current bound 195 AccessIndexedInfoArray _access_indexed_info; // Mapping from Instruction's id to AccessIndexedInfo for in block motion 196 Visitor _visitor; 197 198 public: 199 RangeCheckEliminator(IR *ir); 200 ir() const201 IR *ir() const { return _ir; } 202 203 // Pass over the dominator tree to identify blocks where there's an oppportunity for optimization 204 bool set_process_block_flags(BlockBegin *block); 205 // The core of the optimization work: pass over the dominator tree 206 // to propagate bound information, insert predicate out of loops, 207 // eliminate bound checks when possible and perform in block motion 208 void calc_bounds(BlockBegin *block, BlockBegin *loop_header); 209 // reorder bound checks within a block in order to eliminate some of them 210 void in_block_motion(BlockBegin *block, AccessIndexedList &accessIndexed, InstructionList &arrays); 211 212 // update/access current bound 213 void update_bound(IntegerStack &pushed, Value v, Instruction::Condition cond, Value value, int constant); 214 void update_bound(IntegerStack &pushed, Value v, Bound *bound); 215 Bound *get_bound(Value v); 216 217 bool loop_invariant(BlockBegin *loop_header, Instruction *instruction); // check for loop invariance 218 void add_access_indexed_info(InstructionList &indices, int i, Value instruction, AccessIndexed *ai); // record indexed access for in block motion 219 void remove_range_check(AccessIndexed *ai); // Mark this instructions as not needing a range check 220 void add_if_condition(IntegerStack &pushed, Value x, Value y, Instruction::Condition condition); // Update bound for an If 221 bool in_array_bound(Bound *bound, Value array); // Check whether bound is known to fall within array 222 223 // helper functions to work with predicates 224 Instruction* insert_after(Instruction* insert_position, Instruction* instr, int bci); 225 Instruction* predicate(Instruction* left, Instruction::Condition cond, Instruction* right, ValueStack* state, Instruction *insert_position, int bci=-1); 226 Instruction* predicate_cmp_with_const(Instruction* instr, Instruction::Condition cond, int constant, ValueStack* state, Instruction *insert_position, int bci=1); 227 Instruction* predicate_add(Instruction* left, int left_const, Instruction::Condition cond, Instruction* right, ValueStack* state, Instruction *insert_position, int bci=-1); 228 Instruction* predicate_add_cmp_with_const(Instruction* left, int left_const, Instruction::Condition cond, int constant, ValueStack* state, Instruction *insert_position, int bci=-1); 229 230 void insert_deoptimization(ValueStack *state, Instruction *insert_position, Instruction *array_instr, // Add predicate 231 Instruction *length_instruction, Instruction *lower_instr, int lower, 232 Instruction *upper_instr, int upper, AccessIndexed *ai); 233 bool is_ok_for_deoptimization(Instruction *insert_position, Instruction *array_instr, // Can we safely add a predicate? 234 Instruction *length_instr, Instruction *lower_instr, 235 int lower, Instruction *upper_instr, int upper); 236 void process_if(IntegerStack &pushed, BlockBegin *block, If *cond); // process If Instruction 237 void process_access_indexed(BlockBegin *loop_header, BlockBegin *block, AccessIndexed *ai); // process indexed access 238 239 void dump_condition_stack(BlockBegin *cur_block); 240 static void print_statistics(); 241 }; 242 243 #endif // SHARE_C1_C1_RANGECHECKELIMINATION_HPP 244