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