1 /*
2 * Copyright (c) 1997, 2013, 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_VM_CODE_ICBUFFER_HPP
26 #define SHARE_VM_CODE_ICBUFFER_HPP
27
28 #include "asm/codeBuffer.hpp"
29 #include "code/stubs.hpp"
30 #include "interpreter/bytecodes.hpp"
31 #include "memory/allocation.hpp"
32 #include "utilities/align.hpp"
33
34 //
35 // For CompiledIC's:
36 //
37 // In cases where we do not have MT-safe state transformation,
38 // we go to a transition state, using ICStubs. At a safepoint,
39 // the inline caches are transferred from the transitional code:
40 //
41 // instruction_address --> 01 set xxx_oop, Ginline_cache_klass
42 // 23 jump_to Gtemp, yyyy
43 // 4 nop
44
45 class ICStub: public Stub {
46 private:
47 int _size; // total size of the stub incl. code
48 address _ic_site; // points at call instruction of owning ic-buffer
49 /* stub code follows here */
50 protected:
51 friend class ICStubInterface;
52 // This will be called only by ICStubInterface
53 void initialize(int size,
54 CodeStrings strings) { _size = size; _ic_site = NULL; }
55 void finalize(); // called when a method is removed
56
57 // General info
58 int size() const { return _size; }
59 static int code_size_to_size(int code_size) { return align_up((int)sizeof(ICStub), CodeEntryAlignment) + code_size; }
60
61 public:
62 // Creation
63 void set_stub(CompiledIC *ic, void* cached_value, address dest_addr);
64
65 // Code info
66 address code_begin() const { return (address)this + align_up(sizeof(ICStub), CodeEntryAlignment); }
67 address code_end() const { return (address)this + size(); }
68
69 // Call site info
70 address ic_site() const { return _ic_site; }
71 void clear();
72 bool is_empty() const { return _ic_site == NULL; }
73
74 // stub info
75 address destination() const; // destination of jump instruction
76 void* cached_value() const; // cached_value for stub
77
78 // Debugging
79 void verify() PRODUCT_RETURN;
80 void print() PRODUCT_RETURN;
81
82 // Creation
83 friend ICStub* ICStub_from_destination_address(address destination_address);
84 };
85
86 // ICStub Creation
87 inline ICStub* ICStub_from_destination_address(address destination_address) {
88 ICStub* stub = (ICStub*) (destination_address - align_up(sizeof(ICStub), CodeEntryAlignment));
89 #ifdef ASSERT
90 stub->verify();
91 #endif
92 return stub;
93 }
94
95 class InlineCacheBuffer: public AllStatic {
96 private:
97 // friends
98 friend class ICStub;
99
100 static int ic_stub_code_size();
101
102 static StubQueue* _buffer;
103 static ICStub* _next_stub;
104
105 static CompiledICHolder* _pending_released;
106 static int _pending_count;
107
108 static StubQueue* buffer() { return _buffer; }
109 static void set_next_stub(ICStub* next_stub) { _next_stub = next_stub; }
110 static ICStub* get_next_stub() { return _next_stub; }
111
112 static void init_next_stub();
113
114 static ICStub* new_ic_stub();
115
116
117 // Machine-dependent implementation of ICBuffer
118 static void assemble_ic_buffer_code(address code_begin, void* cached_value, address entry_point);
119 static address ic_buffer_entry_point (address code_begin);
120 static void* ic_buffer_cached_value (address code_begin);
121
122 public:
123
124 // Initialization; must be called before first usage
125 static void initialize();
126
127 // Access
128 static bool contains(address instruction_address);
129
130 // removes the ICStubs after backpatching
131 static void update_inline_caches();
132
133 // for debugging
134 static bool is_empty();
135
136 static void release_pending_icholders();
137 static void queue_for_release(CompiledICHolder* icholder);
138 static int pending_icholder_count() { return _pending_count; }
139
140 // New interface
141 static void create_transition_stub(CompiledIC *ic, void* cached_value, address entry);
142 static address ic_destination_for(CompiledIC *ic);
143 static void* cached_value_for(CompiledIC *ic);
144 };
145
146 #endif // SHARE_VM_CODE_ICBUFFER_HPP