1 /*
2 * Copyright (c) 1997, 2025, 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_CODE_PCDESC_HPP
26 #define SHARE_CODE_PCDESC_HPP
27
28
29 // PcDescs map a physical PC (given as offset from start of nmethod) to
30 // the corresponding source scope and byte code index.
31
32 class nmethod;
33
34 class PcDesc {
35 friend class VMStructs;
36 private:
37 int _pc_offset; // offset from start of nmethod
38 int _scope_decode_offset; // offset for scope in nmethod
39 int _obj_decode_offset;
40
41 enum {
42 PCDESC_reexecute = 1 << 0,
43 PCDESC_return_oop = 1 << 1,
44 PCDESC_rethrow_exception = 1 << 2,
45 PCDESC_has_ea_local_in_scope = 1 << 3,
46 PCDESC_arg_escape = 1 << 4
47 };
48
49 int _flags;
50
51 void set_flag(int mask, bool z) {
52 _flags = z ? (_flags | mask) : (_flags & ~mask);
53 }
54
55 public:
56 int pc_offset() const { return _pc_offset; }
57 int scope_decode_offset() const { return _scope_decode_offset; }
58 int obj_decode_offset() const { return _obj_decode_offset; }
59
60 void set_pc_offset(int x) { _pc_offset = x; }
61 void set_scope_decode_offset(int x) { _scope_decode_offset = x; }
62 void set_obj_decode_offset(int x) { _obj_decode_offset = x; }
63
64 // Constructor (only used for static in nmethod.cpp)
65 // Also used by ScopeDesc::sender()]
66 PcDesc(int pc_offset, int scope_decode_offset, int obj_decode_offset);
67
68 enum {
69 // upper and lower exclusive limits real offsets:
70 lower_offset_limit = -1,
71 upper_offset_limit = (unsigned int)-1 >> 1
72 };
73
74 // Flags
75 bool rethrow_exception() const { return (_flags & PCDESC_rethrow_exception) != 0; }
76 void set_rethrow_exception(bool z) { set_flag(PCDESC_rethrow_exception, z); }
77 bool should_reexecute() const { return (_flags & PCDESC_reexecute) != 0; }
78 void set_should_reexecute(bool z) { set_flag(PCDESC_reexecute, z); }
79
80 // Does pd refer to the same information as pd?
81 bool is_same_info(const PcDesc* pd) {
82 return _scope_decode_offset == pd->_scope_decode_offset &&
83 _obj_decode_offset == pd->_obj_decode_offset &&
84 _flags == pd->_flags;
85 }
86
87 bool return_oop() const { return (_flags & PCDESC_return_oop) != 0; }
88 void set_return_oop(bool z) { set_flag(PCDESC_return_oop, z); }
89
90 // Indicates if there are objects in scope that, based on escape analysis, are local to the
91 // compiled method or local to the current thread, i.e. NoEscape or ArgEscape
92 bool has_ea_local_in_scope() const { return (_flags & PCDESC_has_ea_local_in_scope) != 0; }
93 void set_has_ea_local_in_scope(bool z) { set_flag(PCDESC_has_ea_local_in_scope, z); }
94
95 // Indicates if this pc descriptor is at a call site where objects that do not escape the
96 // current thread are passed as arguments.
97 bool arg_escape() const { return (_flags & PCDESC_arg_escape) != 0; }
98 void set_arg_escape(bool z) { set_flag(PCDESC_arg_escape, z); }
99
100 // Returns the real pc
101 address real_pc(const nmethod* code) const;
102
103 void print(nmethod* code) { print_on(tty, code); }
104 void print_on(outputStream* st, nmethod* code);
105 bool verify(nmethod* code);
106 };
107
108 #endif // SHARE_CODE_PCDESC_HPP