--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/c1/c1_RangeCheckElimination.hpp Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,243 @@
+/*
+ * Copyright (c) 2012, 2016, 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;
+
+ typedef GrowableArray<BlockBegin*> BlockBeginList;
+ typedef GrowableArray<int> IntegerStack;
+
+ class Verification : public BlockClosure {
+ // RangeCheckEliminator::Verification should never get instatiated on the heap.
+ private:
+ void* operator new(size_t size) throw();
+ void* operator new[](size_t size) throw();
+ void operator delete(void* p) { ShouldNotReachHere(); }
+ void operator delete[](void* p) { ShouldNotReachHere(); }
+
+ 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();
+
+#ifdef ASSERT
+ void add_assertion(Instruction *instruction, Instruction *position, int i, 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_ProfileCall (ProfileCall* x) { /* nothing to do */ };
+ void do_ProfileReturnType (ProfileReturnType* 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 */ };
+#ifdef ASSERT
+ void do_Assert (Assert* x) { /* nothing to do */ };
+#endif
+ };
+
+#ifdef ASSERT
+ void add_assertions(Bound *bound, Instruction *instruction, Instruction *position);
+#endif
+
+ typedef GrowableArray<Bound*> BoundStack;
+ typedef GrowableArray<BoundStack*> BoundMap;
+ typedef GrowableArray<AccessIndexed*> AccessIndexedList;
+ typedef GrowableArray<Instruction*> InstructionList;
+
+ class AccessIndexedInfo : public CompilationResourceObj {
+ public:
+ AccessIndexedList *_list;
+ int _min;
+ int _max;
+ };
+
+ typedef GrowableArray<AccessIndexedInfo*> AccessIndexedInfoArray;
+ 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 i, 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
+
+ // helper functions to work with predicates
+ Instruction* insert_after(Instruction* insert_position, Instruction* instr, int bci);
+ Instruction* predicate(Instruction* left, Instruction::Condition cond, Instruction* right, ValueStack* state, Instruction *insert_position, int bci=-1);
+ Instruction* predicate_cmp_with_const(Instruction* instr, Instruction::Condition cond, int constant, ValueStack* state, Instruction *insert_position, int bci=1);
+ Instruction* predicate_add(Instruction* left, int left_const, Instruction::Condition cond, Instruction* right, ValueStack* state, Instruction *insert_position, int bci=-1);
+ Instruction* predicate_add_cmp_with_const(Instruction* left, int left_const, Instruction::Condition cond, int constant, ValueStack* state, Instruction *insert_position, int bci=-1);
+
+ 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