--- /dev/null 2012-11-23 07:18:02.922988661 +0100 +++ new/src/share/vm/c1/c1_RangeCheckElimination.hpp 2013-02-20 17:41:14.290667702 +0100 @@ -0,0 +1,233 @@ +/* + * Copyright (c) 2012, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA + * or visit www.oracle.com if you need additional information or have any + * questions. + * + */ + +#ifndef SHARE_VM_C1_C1_RANGECHECKELIMINATION_HPP +#define SHARE_VM_C1_C1_RANGECHECKELIMINATION_HPP + +#include "c1/c1_Instruction.hpp" + +// Base class for range check elimination +class RangeCheckElimination : AllStatic { +public: + static void eliminate(IR *ir); +}; + +// Implementation +class RangeCheckEliminator VALUE_OBJ_CLASS_SPEC { +private: + int _number_of_instructions; + bool _optimistic; // Insert predicates and deoptimize when they fail + IR *_ir; + + define_array(BlockBeginArray, BlockBegin*) + define_stack(BlockBeginList, BlockBeginArray) + define_stack(IntegerStack, intArray) + define_array(IntegerMap, IntegerStack*) + + class Verification : public _ValueObj /*VALUE_OBJ_CLASS_SPEC*/, public BlockClosure { + private: + IR *_ir; + boolArray _used; + BlockBeginList _current; + BlockBeginList _successors; + + public: + Verification(IR *ir); + virtual void block_do(BlockBegin *block); + bool can_reach(BlockBegin *start, BlockBegin *end, BlockBegin *dont_use = NULL); + bool dominates(BlockBegin *dominator, BlockBegin *block); + }; + +public: + // Bounds for an instruction in the form x + c which c integer + // constant and x another instruction + class Bound : public CompilationResourceObj { + private: + int _upper; + Value _upper_instr; + int _lower; + Value _lower_instr; + + public: + Bound(); + Bound(Value v); + Bound(Instruction::Condition cond, Value v, int constant = 0); + Bound(int lower, Value lower_instr, int upper, Value upper_instr); + ~Bound(); + +#ifndef PRODUCT + void add_assertion(Instruction *instruction, Instruction *position, int integer, Value instr, Instruction::Condition cond); +#endif + int upper(); + Value upper_instr(); + int lower(); + Value lower_instr(); + void print(); + bool check_no_overflow(int const_value); + void or_op(Bound *b); + void and_op(Bound *b); + bool has_upper(); + bool has_lower(); + void set_upper(int upper, Value upper_instr); + void set_lower(int lower, Value lower_instr); + bool is_smaller(Bound *b); + void remove_upper(); + void remove_lower(); + void add_constant(int value); + Bound *copy(); + + private: + void init(); + }; + + + class Visitor : public InstructionVisitor { + private: + Bound *_bound; + RangeCheckEliminator *_rce; + + public: + void set_range_check_eliminator(RangeCheckEliminator *rce) { _rce = rce; } + Bound *bound() const { return _bound; } + void clear_bound() { _bound = NULL; } + + protected: + // visitor functions + void do_Constant (Constant* x); + void do_IfOp (IfOp* x); + void do_LogicOp (LogicOp* x); + void do_ArithmeticOp (ArithmeticOp* x); + void do_Phi (Phi* x); + + void do_StoreField (StoreField* x) { /* nothing to do */ }; + void do_StoreIndexed (StoreIndexed* x) { /* nothing to do */ }; + void do_MonitorEnter (MonitorEnter* x) { /* nothing to do */ }; + void do_MonitorExit (MonitorExit* x) { /* nothing to do */ }; + void do_Invoke (Invoke* x) { /* nothing to do */ }; + void do_UnsafePutRaw (UnsafePutRaw* x) { /* nothing to do */ }; + void do_UnsafePutObject(UnsafePutObject* x) { /* nothing to do */ }; + void do_Intrinsic (Intrinsic* x) { /* nothing to do */ }; + void do_Local (Local* 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_ShiftOp (ShiftOp* x) { /* nothing to do */ }; + void do_CompareOp (CompareOp* x) { /* nothing to do */ }; + void do_Convert (Convert* x) { /* nothing to do */ }; + void do_NullCheck (NullCheck* x) { /* nothing to do */ }; + void do_TypeCast (TypeCast* 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_UnsafeGetAndSetObject(UnsafeGetAndSetObject* 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_ProfileInvoke (ProfileInvoke* x) { /* nothing to do */ }; + void do_RuntimeCall (RuntimeCall* x) { /* nothing to do */ }; + void do_MemBar (MemBar* x) { /* nothing to do */ }; + void do_RangeCheckPredicate(RangeCheckPredicate* x) { /* nothing to do */ }; + void do_Assert (Assert* x) { /* nothing to do */ }; + }; + +#ifndef PRODUCT + void add_assertions(Bound *bound, Instruction *instruction, Instruction *position); +#endif + + define_array(BoundArray, Bound *) + define_stack(BoundStack, BoundArray) + define_array(BoundMap, BoundStack *) + define_array(AccessIndexedArray, AccessIndexed *) + define_stack(AccessIndexedList, AccessIndexedArray) + define_array(InstructionArray, Instruction *) + define_stack(InstructionList, InstructionArray) + + class AccessIndexedInfo : public CompilationResourceObj { + public: + AccessIndexedList *_list; + int _min; + int _max; + }; + + define_array(AccessIndexedInfoArray, AccessIndexedInfo *) + BoundMap _bounds; // Mapping from Instruction's id to current bound + AccessIndexedInfoArray _access_indexed_info; // Mapping from Instruction's id to AccessIndexedInfo for in block motion + Visitor _visitor; + +public: + RangeCheckEliminator(IR *ir); + + IR *ir() const { return _ir; } + + // Pass over the dominator tree to identify blocks where there's an oppportunity for optimization + bool set_process_block_flags(BlockBegin *block); + // The core of the optimization work: pass over the dominator tree + // to propagate bound information, insert predicate out of loops, + // eliminate bound checks when possible and perform in block motion + void calc_bounds(BlockBegin *block, BlockBegin *loop_header); + // reorder bound checks within a block in order to eliminate some of them + void in_block_motion(BlockBegin *block, AccessIndexedList &accessIndexed, InstructionList &arrays); + + // update/access current bound + void update_bound(IntegerStack &pushed, Value v, Instruction::Condition cond, Value value, int constant); + void update_bound(IntegerStack &pushed, Value v, Bound *bound); + Bound *get_bound(Value v); + + bool loop_invariant(BlockBegin *loop_header, Instruction *instruction); // check for loop invariance + void add_access_indexed_info(InstructionList &indices, int integer, Value instruction, AccessIndexed *ai); // record indexed access for in block motion + void remove_range_check(AccessIndexed *ai); // Mark this instructions as not needing a range check + void add_if_condition(IntegerStack &pushed, Value x, Value y, Instruction::Condition condition); // Update bound for an If + bool in_array_bound(Bound *bound, Value array); // Check whether bound is known to fall within array + void insert_deoptimization(ValueStack *state, Instruction *insert_position, Instruction *array_instr, // Add predicate + Instruction *length_instruction, Instruction *lower_instr, int lower, + Instruction *upper_instr, int upper, AccessIndexed *ai); + bool is_ok_for_deoptimization(Instruction *insert_position, Instruction *array_instr, // Can we safely add a predicate? + Instruction *length_instr, Instruction *lower_instr, + int lower, Instruction *upper_instr, int upper); + void process_if(IntegerStack &pushed, BlockBegin *block, If *cond); // process If Instruction + void process_access_indexed(BlockBegin *loop_header, BlockBegin *block, AccessIndexed *ai); // process indexed access + + void dump_condition_stack(BlockBegin *cur_block); + static void print_statistics(); +}; + +#endif // SHARE_VM_C1_C1_RANGECHECKELIMINATION_HPP