1 /*
2 * Copyright (c) 1997, 2019, 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_ICBUFFER_HPP
26 #define SHARE_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 "runtime/safepointVerifiers.hpp"
33 #include "utilities/align.hpp"
34 #include "utilities/debug.hpp"
35 #include "utilities/macros.hpp"
36
37 //
38 // For CompiledIC's:
39 //
40 // In cases where we do not have MT-safe state transformation,
41 // we go to a transition state, using ICStubs. At a safepoint,
42 // the inline caches are transferred from the transitional code:
43 //
44 // instruction_address --> 01 set xxx_oop, Ginline_cache_klass
45 // 23 jump_to Gtemp, yyyy
46 // 4 nop
47
48 class ICStub: public Stub {
49 private:
50 int _size; // total size of the stub incl. code
51 address _ic_site; // points at call instruction of owning ic-buffer
52 /* stub code follows here */
53 protected:
54 friend class ICStubInterface;
55 // This will be called only by ICStubInterface
initialize(int size,CodeStrings strings)56 void initialize(int size,
57 CodeStrings strings) { _size = size; _ic_site = NULL; }
58 void finalize(); // called when a method is removed
59
60 // General info
size() const61 int size() const { return _size; }
code_size_to_size(int code_size)62 static int code_size_to_size(int code_size) { return align_up((int)sizeof(ICStub), CodeEntryAlignment) + code_size; }
63
64 public:
65 // Creation
66 void set_stub(CompiledIC *ic, void* cached_value, address dest_addr);
67
68 // Code info
code_begin() const69 address code_begin() const { return (address)this + align_up(sizeof(ICStub), CodeEntryAlignment); }
code_end() const70 address code_end() const { return (address)this + size(); }
71
72 // Call site info
ic_site() const73 address ic_site() const { return _ic_site; }
74 void clear();
is_empty() const75 bool is_empty() const { return _ic_site == NULL; }
76
77 // stub info
78 address destination() const; // destination of jump instruction
79 void* cached_value() const; // cached_value for stub
80
81 // Debugging
82 void verify() PRODUCT_RETURN;
83 void print() PRODUCT_RETURN;
84
85 // Creation
86 friend ICStub* ICStub_from_destination_address(address destination_address);
87 };
88
89 // ICStub Creation
ICStub_from_destination_address(address destination_address)90 inline ICStub* ICStub_from_destination_address(address destination_address) {
91 ICStub* stub = (ICStub*) (destination_address - align_up(sizeof(ICStub), CodeEntryAlignment));
92 #ifdef ASSERT
93 stub->verify();
94 #endif
95 return stub;
96 }
97
98 #ifdef ASSERT
99 // The ICRefillVerifier class is a stack allocated RAII object used to
100 // detect if a failed IC transition that required IC stub refilling has
101 // been accidentally missed. It is up to the caller to in that case
102 // refill IC stubs.
103 class ICRefillVerifier: StackObj {
104 bool _refill_requested;
105 bool _refill_remembered;
106
107 public:
108 ICRefillVerifier();
109 ~ICRefillVerifier();
110
request_refill()111 void request_refill() { _refill_requested = true; }
request_remembered()112 void request_remembered() { _refill_remembered = true; }
113 };
114
115 // The ICRefillVerifierMark is used to set the thread's current
116 // ICRefillVerifier to a provided one. This is useful in particular
117 // when transitioning IC stubs in parallel and refilling from the
118 // master thread invoking the IC stub transitioning code.
119 class ICRefillVerifierMark: StackObj {
120 public:
121 ICRefillVerifierMark(ICRefillVerifier* verifier);
122 ~ICRefillVerifierMark();
123 };
124 #else
125 class ICRefillVerifier: StackObj {
126 public:
ICRefillVerifier()127 ICRefillVerifier() {}
128 };
129 class ICRefillVerifierMark: StackObj {
130 public:
ICRefillVerifierMark(ICRefillVerifier * verifier)131 ICRefillVerifierMark(ICRefillVerifier* verifier) {}
132 };
133 #endif
134
135 class InlineCacheBuffer: public AllStatic {
136 private:
137 // friends
138 friend class ICStub;
139
140 static int ic_stub_code_size();
141
142 static StubQueue* _buffer;
143
144 static CompiledICHolder* _pending_released;
145 static int _pending_count;
146
buffer()147 static StubQueue* buffer() { return _buffer; }
148
149 static ICStub* new_ic_stub();
150
151 // Machine-dependent implementation of ICBuffer
152 static void assemble_ic_buffer_code(address code_begin, void* cached_value, address entry_point);
153 static address ic_buffer_entry_point (address code_begin);
154 static void* ic_buffer_cached_value (address code_begin);
155
156 public:
157
158 // Initialization; must be called before first usage
159 static void initialize();
160
161 // Access
162 static bool contains(address instruction_address);
163
164 // removes the ICStubs after backpatching
165 static void update_inline_caches();
166 static void refill_ic_stubs();
167
168 // for debugging
169 static bool is_empty();
170
171 static void release_pending_icholders();
172 static void queue_for_release(CompiledICHolder* icholder);
pending_icholder_count()173 static int pending_icholder_count() { return _pending_count; }
174
175 // New interface
176 static bool create_transition_stub(CompiledIC *ic, void* cached_value, address entry);
177 static address ic_destination_for(CompiledIC *ic);
178 static void* cached_value_for(CompiledIC *ic);
179 };
180
181 #endif // SHARE_CODE_ICBUFFER_HPP
182