1 /*
2 * Copyright (c) 1997, 2016, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2014, Red Hat Inc. All rights reserved.
4 * Copyright (c) 2015, Linaro Ltd. All rights reserved.
5 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
6 *
7 * This code is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License version 2 only, as
9 * published by the Free Software Foundation.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 *
25 */
26
27 #include "precompiled.hpp"
28 #include "asm/macroAssembler.inline.hpp"
29 #include "code/compiledIC.hpp"
30 #include "code/icBuffer.hpp"
31 #include "code/nmethod.hpp"
32 #include "memory/resourceArea.hpp"
33 #include "runtime/mutexLocker.hpp"
34 #include "runtime/safepoint.hpp"
35
36 // ----------------------------------------------------------------------------
37
38 #define __ _masm.
39 address CompiledStaticCall::emit_to_interp_stub(CodeBuffer &cbuf, address mark) {
40 // Stub is fixed up when the corresponding call is converted from
41 // calling compiled code to calling interpreted code.
42 // mov rmethod, 0
43 // jmp -4 # to self
44
45 if (mark == NULL) {
46 mark = cbuf.insts_mark(); // Get mark within main instrs section.
47 }
48
49 // Note that the code buffer's insts_mark is always relative to insts.
50 // That's why we must use the macroassembler to generate a stub.
51 MacroAssembler _masm(&cbuf);
52
53 address base = __ start_a_stub(to_interp_stub_size());
54
55 int offset = __ offset();
56 if (base == NULL) {
57 return NULL; // CodeBuffer::expand failed
58 }
59 // static stub relocation stores the instruction address of the call
60 __ relocate(static_stub_Relocation::spec(mark));
61 // static stub relocation also tags the Method* in the code-stream.
62 __ mov_metadata(rmethod, (Metadata*)NULL);
63 __ movptr(rscratch1, 0);
64 __ b(rscratch1);
65
66 assert((__ offset() - offset) <= (int)to_interp_stub_size(), "stub too big");
67 __ end_a_stub();
68 return base;
69 }
70 #undef __
71
72 int CompiledStaticCall::to_interp_stub_size() {
73 return 7 * NativeInstruction::arm_insn_sz;
74 }
75
76 int CompiledStaticCall::to_trampoline_stub_size() {
77 // AArch32 doesn't use trampoline stubs.
78 return 0;
79 }
80
81 // Relocation entries for call stub, compiled java to interpreter.
82 int CompiledStaticCall::reloc_to_interp_stub() {
83 return 4; // 3 in emit_to_interp_stub + 1 in emit_call
84 }
85
86 void CompiledDirectStaticCall::set_to_interpreted(const methodHandle& callee, address entry) {
87 address stub = find_stub(false /* is_aot */);
88 guarantee(stub != NULL, "stub not found");
89
90 if (TraceICs) {
91 ResourceMark rm;
92 tty->print_cr("CompiledDirectStaticCall@" INTPTR_FORMAT ": set_to_interpreted %s",
93 p2i(instruction_address()),
94 callee->name_and_sig_as_C_string());
95 }
96
97 // Creation also verifies the object.
98 NativeMovConstReg* method_holder = nativeMovConstReg_at(stub);
99 NativeJump* jump = NativeJump::from(method_holder->next_instruction_address());
100 #ifndef PRODUCT
101 // read the value once
102 volatile intptr_t data = method_holder->data();
103 assert(data == 0 || data == (intptr_t)callee(),
104 "a) MT-unsafe modification of inline cache");
105 assert(data == 0 || jump->jump_destination() == entry,
106 "b) MT-unsafe modification of inline cache");
107 #endif
108 // Update stub.
109 method_holder->set_data((intptr_t)callee());
110 jump->set_jump_destination(entry);
111 ICache::invalidate_range(stub, to_interp_stub_size());
112 // Update jump to call.
113 set_destination_mt_safe(stub);
114 }
115
116 void CompiledDirectStaticCall::set_stub_to_clean(static_stub_Relocation* static_stub) {
117 assert (CompiledIC_lock->is_locked() || SafepointSynchronize::is_at_safepoint(), "mt unsafe call");
118 // Reset stub.
119 address stub = static_stub->addr();
120 assert(stub != NULL, "stub not found");
121 // Creation also verifies the object.
122 NativeMovConstReg* method_holder = nativeMovConstReg_at(stub);
123 method_holder->set_data(0);
124 }
125
126 //-----------------------------------------------------------------------------
127 // Non-product mode code
128 #ifndef PRODUCT
129
130 void CompiledDirectStaticCall::verify() {
131 // Verify call.
132 _call->verify();
133 if (os::is_MP()) {
134 _call->verify_alignment();
135 }
136
137 // Verify stub.
138 address stub = find_stub(false /* is_aot */);
139 assert(stub != NULL, "no stub found for static call");
140 // Creation also verifies the object.
141 NativeMovConstReg* method_holder = nativeMovConstReg_at(stub);
142 NativeJump* jump = nativeJump_at(method_holder->next_instruction_address());
143
144 // Verify state.
145 assert(is_clean() || is_call_to_compiled() || is_call_to_interpreted(), "sanity check");
146 }
147
148 #endif // !PRODUCT