1 /* 2 * Copyright (c) 1997, 2018, 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 "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 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 61 int size() const { return _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 69 address code_begin() const { return (address)this + align_up(sizeof(ICStub), CodeEntryAlignment); } 70 address code_end() const { return (address)this + size(); } 71 72 // Call site info 73 address ic_site() const { return _ic_site; } 74 void clear(); 75 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 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(); 110 111 void request_refill() { _refill_requested = true; } 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 #endif 125 126 class InlineCacheBuffer: public AllStatic { 127 private: 128 // friends 129 friend class ICStub; 130 131 static int ic_stub_code_size(); 132 133 static StubQueue* _buffer; 134 135 static CompiledICHolder* _pending_released; 136 static int _pending_count; 137 138 static StubQueue* buffer() { return _buffer; } 139 140 static ICStub* new_ic_stub(); 141 142 // Machine-dependent implementation of ICBuffer 143 static void assemble_ic_buffer_code(address code_begin, void* cached_value, address entry_point); 144 static address ic_buffer_entry_point (address code_begin); 145 static void* ic_buffer_cached_value (address code_begin); 146 147 public: 148 149 // Initialization; must be called before first usage 150 static void initialize(); 151 152 // Access 153 static bool contains(address instruction_address); 154 155 // removes the ICStubs after backpatching 156 static void update_inline_caches(); 157 static void refill_ic_stubs(); 158 159 // for debugging 160 static bool is_empty(); 161 162 static void release_pending_icholders(); 163 static void queue_for_release(CompiledICHolder* icholder); 164 static int pending_icholder_count() { return _pending_count; } 165 166 // New interface 167 static bool create_transition_stub(CompiledIC *ic, void* cached_value, address entry); 168 static address ic_destination_for(CompiledIC *ic); 169 static void* cached_value_for(CompiledIC *ic); 170 }; 171 172 #endif // SHARE_VM_CODE_ICBUFFER_HPP