1 /*
2 * Copyright (c) 1997, 2014, 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 #include "precompiled.hpp"
26 #include "asm/macroAssembler.inline.hpp"
27 #include "code/compiledIC.hpp"
28 #include "code/icBuffer.hpp"
29 #include "code/nmethod.hpp"
30 #include "memory/resourceArea.hpp"
31 #include "runtime/mutexLocker.hpp"
32 #include "runtime/safepoint.hpp"
33
34 // Release the CompiledICHolder* associated with this call site is there is one.
35 void CompiledIC::cleanup_call_site(virtual_call_Relocation* call_site) {
36 // This call site might have become stale so inspect it carefully.
37 NativeCall* call = nativeCall_at(call_site->addr());
38 if (is_icholder_entry(call->destination())) {
39 NativeMovConstReg* value = nativeMovConstReg_at(call_site->cached_value());
40 InlineCacheBuffer::queue_for_release((CompiledICHolder*)value->data());
41 }
42 }
43
44 bool CompiledIC::is_icholder_call_site(virtual_call_Relocation* call_site) {
45 // This call site might have become stale so inspect it carefully.
46 NativeCall* call = nativeCall_at(call_site->addr());
47 return is_icholder_entry(call->destination());
48 }
49
50 // ----------------------------------------------------------------------------
51
52 #define __ _masm.
53 address CompiledStaticCall::emit_to_interp_stub(CodeBuffer &cbuf, address mark) {
54 // Stub is fixed up when the corresponding call is converted from
55 // calling compiled code to calling interpreted code.
56 // movq rbx, 0
57 // jmp -5 # to self
58
59 if (mark == NULL) {
60 mark = cbuf.insts_mark(); // Get mark within main instrs section.
61 }
62
63 // Note that the code buffer's insts_mark is always relative to insts.
64 // That's why we must use the macroassembler to generate a stub.
65 MacroAssembler _masm(&cbuf);
66
67 address base = __ start_a_stub(to_interp_stub_size());
68 if (base == NULL) {
69 return NULL; // CodeBuffer::expand failed.
70 }
71 // Static stub relocation stores the instruction address of the call.
72 __ relocate(static_stub_Relocation::spec(mark), Assembler::imm_operand);
73 // Static stub relocation also tags the Method* in the code-stream.
74 __ mov_metadata(rbx, (Metadata*) NULL); // Method is zapped till fixup time.
75 // This is recognized as unresolved by relocs/nativeinst/ic code.
76 __ jump(RuntimeAddress(__ pc()));
77
78 assert(__ pc() - base <= to_interp_stub_size(), "wrong stub size");
79
80 // Update current stubs pointer and restore insts_end.
81 __ end_a_stub();
82 return base;
83 }
84 #undef __
85
86 int CompiledStaticCall::to_interp_stub_size() {
87 return NOT_LP64(10) // movl; jmp
88 LP64_ONLY(15); // movq (1+1+8); jmp (1+4)
89 }
90
91 // Relocation entries for call stub, compiled java to interpreter.
92 int CompiledStaticCall::reloc_to_interp_stub() {
93 return 4; // 3 in emit_to_interp_stub + 1 in emit_call
94 }
95
96 void CompiledStaticCall::set_to_interpreted(methodHandle callee, address entry) {
97 address stub = find_stub();
98 guarantee(stub != NULL, "stub not found");
99
100 if (TraceICs) {
101 ResourceMark rm;
102 tty->print_cr("CompiledStaticCall@" INTPTR_FORMAT ": set_to_interpreted %s",
103 p2i(instruction_address()),
104 callee->name_and_sig_as_C_string());
105 }
106
107 // Creation also verifies the object.
108 NativeMovConstReg* method_holder = nativeMovConstReg_at(stub);
109 NativeJump* jump = nativeJump_at(method_holder->next_instruction_address());
110
111 #ifdef ASSERT
112 // read the value once
113 intptr_t data = method_holder->data();
114 address destination = jump->jump_destination();
115 assert(data == 0 || data == (intptr_t)callee(),
116 "a) MT-unsafe modification of inline cache");
117 assert(destination == (address)-1 || destination == entry,
118 "b) MT-unsafe modification of inline cache");
119 #endif
120
121 // Update stub.
122 method_holder->set_data((intptr_t)callee());
123 jump->set_jump_destination(entry);
124
125 // Update jump to call.
126 set_destination_mt_safe(stub);
127 }
128
129 void CompiledStaticCall::set_stub_to_clean(static_stub_Relocation* static_stub) {
130 assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "mt unsafe call");
131 // Reset stub.
132 address stub = static_stub->addr();
133 assert(stub != NULL, "stub not found");
134 // Creation also verifies the object.
135 NativeMovConstReg* method_holder = nativeMovConstReg_at(stub);
136 method_holder->set_data(0);
137 NativeJump* jump = nativeJump_at(method_holder->next_instruction_address());
138 jump->set_jump_destination((address)-1);
139 }
140
141
142 //-----------------------------------------------------------------------------
143 // Non-product mode code
144 #ifndef PRODUCT
145
146 void CompiledStaticCall::verify() {
147 // Verify call.
148 NativeCall::verify();
149 if (os::is_MP()) {
150 verify_alignment();
151 }
152
153 // Verify stub.
154 address stub = find_stub();
155 assert(stub != NULL, "no stub found for static call");
156 // Creation also verifies the object.
157 NativeMovConstReg* method_holder = nativeMovConstReg_at(stub);
158 NativeJump* jump = nativeJump_at(method_holder->next_instruction_address());
159
160 // Verify state.
161 assert(is_clean() || is_call_to_compiled() || is_call_to_interpreted(), "sanity check");
162 }
163 #endif // !PRODUCT