bcEscapeAnalyzer.hpp revision 78
2N/A/*
2N/A * Copyright 2005-2006 Sun Microsystems, Inc. All Rights Reserved.
2N/A * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
2N/A *
2N/A * This code is free software; you can redistribute it and/or modify it
2N/A * under the terms of the GNU General Public License version 2 only, as
2N/A * published by the Free Software Foundation.
2N/A *
2N/A * This code is distributed in the hope that it will be useful, but WITHOUT
2N/A * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
2N/A * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
2N/A * version 2 for more details (a copy is included in the LICENSE file that
2N/A * accompanied this code).
2N/A *
2N/A * You should have received a copy of the GNU General Public License version
2N/A * 2 along with this work; if not, write to the Free Software Foundation,
2N/A * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
2N/A *
2N/A * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
2N/A * CA 95054 USA or visit www.sun.com if you need additional information or
2N/A * have any questions.
2N/A *
2N/A */
2N/A
2N/Adefine_array(ciObjectArray, ciObject*);
2N/Adefine_stack(ciObjectList, ciObjectArray);
2N/A
2N/A// This class implements a fast, conservative analysis of effect of methods
2N/A// on the escape state of their arguments. The analysis is at the bytecode
2N/A// level.
2N/A
2N/Aclass ciMethodBlocks;
2N/Aclass ciBlock;
2N/A
2N/Aclass BCEscapeAnalyzer : public ResourceObj {
2N/A private:
2N/A bool _conservative; // If true, return maximally
2N/A // conservative results.
2N/A ciMethod* _method;
2N/A ciMethodData* _methodData;
2N/A int _arg_size;
2N/A
2N/A intStack _stack;
2N/A
2N/A BitMap _arg_local;
2N/A BitMap _arg_stack;
2N/A BitMap _arg_returned;
2N/A BitMap _dirty;
2N/A enum{ ARG_OFFSET_MAX = 31};
2N/A uint *_arg_modified;
2N/A
2N/A bool _return_local;
2N/A bool _return_allocated;
2N/A bool _allocated_escapes;
2N/A bool _unknown_modified;
2N/A
2N/A ciObjectList _dependencies;
2N/A
2N/A ciMethodBlocks *_methodBlocks;
2N/A
2N/A BCEscapeAnalyzer* _parent;
2N/A int _level;
2N/A
2N/A class ArgumentMap;
2N/A class StateInfo;
2N/A
2N/A // helper functions
2N/A bool is_argument(int i) { return i >= 0 && i < _arg_size; }
2N/A
2N/A void raw_push(int i) { _stack.push(i); }
2N/A int raw_pop() { return _stack.is_empty() ? -1 : _stack.pop(); }
2N/A void apush(int i) { raw_push(i); }
2N/A void spush() { raw_push(-1); }
2N/A void lpush() { spush(); spush(); }
2N/A int apop() { return raw_pop(); }
2N/A void spop() { assert(_stack.is_empty() || _stack.top() == -1, ""); raw_pop(); }
2N/A void lpop() { spop(); spop(); }
2N/A
2N/A void set_returned(ArgumentMap vars);
2N/A bool is_argument(ArgumentMap vars);
2N/A bool is_arg_stack(ArgumentMap vars);
2N/A void clear_bits(ArgumentMap vars, BitMap &bs);
2N/A void set_method_escape(ArgumentMap vars);
2N/A void set_global_escape(ArgumentMap vars);
2N/A void set_dirty(ArgumentMap vars);
2N/A void set_modified(ArgumentMap vars, int offs, int size);
2N/A
2N/A bool is_recursive_call(ciMethod* callee);
2N/A void add_dependence(ciKlass *klass, ciMethod *meth);
2N/A void propagate_dependencies(ciMethod *meth);
void invoke(StateInfo &state, Bytecodes::Code code, ciMethod* target, ciKlass* holder);
void iterate_one_block(ciBlock *blk, StateInfo &state, GrowableArray<ciBlock *> &successors);
void iterate_blocks(Arena *);
void merge_block_states(StateInfo *blockstates, ciBlock *dest, StateInfo *s_state);
// analysis
void initialize();
void clear_escape_info();
void compute_escape_info();
vmIntrinsics::ID known_intrinsic();
bool compute_escape_for_intrinsic(vmIntrinsics::ID iid);
bool do_analysis();
void read_escape_info();
bool contains(uint arg_set1, uint arg_set2);
public:
BCEscapeAnalyzer(ciMethod* method, BCEscapeAnalyzer* parent = NULL);
// accessors
ciMethod* method() const { return _method; }
ciMethodData* methodData() const { return _methodData; }
BCEscapeAnalyzer* parent() const { return _parent; }
int level() const { return _level; }
ciObjectList* dependencies() { return &_dependencies; }
bool has_dependencies() const { return !_dependencies.is_empty(); }
// retrieval of interprocedural escape information
// The given argument does not escape the callee.
bool is_arg_local(int i) const {
return !_conservative && _arg_local.at(i);
}
// The given argument escapes the callee, but does not become globally
// reachable.
bool is_arg_stack(int i) const {
return !_conservative && _arg_stack.at(i);
}
// The given argument does not escape globally, and may be returned.
bool is_arg_returned(int i) const {
return !_conservative && _arg_returned.at(i); }
// True iff only input arguments are returned.
bool is_return_local() const {
return !_conservative && _return_local;
}
// True iff only newly allocated unescaped objects are returned.
bool is_return_allocated() const {
return !_conservative && _return_allocated && !_allocated_escapes;
}
// Tracking of argument modification
enum {OFFSET_ANY = -1};
bool is_arg_modified(int arg, int offset, int size_in_bytes);
void set_arg_modified(int arg, int offset, int size_in_bytes);
bool has_non_arg_side_affects() { return _unknown_modified; }
// Copy dependencies from this analysis into "deps"
void copy_dependencies(Dependencies *deps);
#ifndef PRODUCT
// dump escape information
void dump();
#endif
};