1 /*
2 * Copyright (c) 1997, 2003, 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 //
26 // For CompiledIC's:
27 //
28 // In cases where we do not have MT-safe state transformation,
29 // we go to a transition state, using ICStubs. At a safepoint,
30 // the inline caches are transferred from the transitional code:
31 //
32 // instruction_address --> 01 set xxx_oop, Ginline_cache_klass
33 // 23 jump_to Gtemp, yyyy
34 // 4 nop
35
36 class ICStub: public Stub {
37 private:
38 int _size; // total size of the stub incl. code
39 address _ic_site; // points at call instruction of owning ic-buffer
40 /* stub code follows here */
41 protected:
42 friend class ICStubInterface;
43 // This will be called only by ICStubInterface
44 void initialize(int size) { _size = size; _ic_site = NULL; }
45 void finalize(); // called when a method is removed
46
47 // General info
48 int size() const { return _size; }
49 static int code_size_to_size(int code_size) { return round_to(sizeof(ICStub), CodeEntryAlignment) + code_size; }
50
51 public:
52 // Creation
53 void set_stub(CompiledIC *ic, oop cached_value, address dest_addr);
54
55 // Code info
56 address code_begin() const { return (address)this + round_to(sizeof(ICStub), CodeEntryAlignment); }
57 address code_end() const { return (address)this + size(); }
58
59 // Call site info
60 address ic_site() const { return _ic_site; }
61 void clear();
62 bool is_empty() const { return _ic_site == NULL; }
63
64 // stub info
65 address destination() const; // destination of jump instruction
66 oop cached_oop() const; // cached_oop for stub
67
68 // Debugging
69 void verify() PRODUCT_RETURN;
70 void print() PRODUCT_RETURN;
71
72 // Creation
73 friend ICStub* ICStub_from_destination_address(address destination_address);
74 };
75
76 // ICStub Creation
77 inline ICStub* ICStub_from_destination_address(address destination_address) {
78 ICStub* stub = (ICStub*) (destination_address - round_to(sizeof(ICStub), CodeEntryAlignment));
79 #ifdef ASSERT
80 stub->verify();
81 #endif
82 return stub;
83 }
84
85 class InlineCacheBuffer: public AllStatic {
86 private:
87 // friends
88 friend class ICStub;
89
90 static int ic_stub_code_size();
91
92 static StubQueue* _buffer;
93 static ICStub* _next_stub;
94
95 static StubQueue* buffer() { return _buffer; }
96 static void set_next_stub(ICStub* next_stub) { _next_stub = next_stub; }
97 static ICStub* get_next_stub() { return _next_stub; }
98
99 static void init_next_stub();
100
101 static ICStub* new_ic_stub();
102
103
104 // Machine-dependent implementation of ICBuffer
105 static void assemble_ic_buffer_code(address code_begin, oop cached_oop, address entry_point);
106 static address ic_buffer_entry_point (address code_begin);
107 static oop ic_buffer_cached_oop (address code_begin);
108
109 public:
110
111 // Initialization; must be called before first usage
112 static void initialize();
113
114 // Access
115 static bool contains(address instruction_address);
116
117 // removes the ICStubs after backpatching
118 static void update_inline_caches();
119
120 // for debugging
121 static bool is_empty();
122
123
124 // New interface
125 static void create_transition_stub(CompiledIC *ic, oop cached_oop, address entry);
126 static address ic_destination_for(CompiledIC *ic);
127 static oop cached_oop_for(CompiledIC *ic);
128 };