1 /*
2 * Copyright (c) 1997, 2019, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2014, 2018, Red Hat Inc. All rights reserved.
4 * Copyright (c) 2020, 2021, Huawei Technologies Co., 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 precond(cbuf.stubs()->start() != badAddress);
41 precond(cbuf.stubs()->end() != badAddress);
42 // Stub is fixed up when the corresponding call is converted from
43 // calling compiled code to calling interpreted code.
44 // mv xmethod, 0
45 // jalr -4 # to self
46
47 if (mark == NULL) {
48 mark = cbuf.insts_mark(); // Get mark within main instrs section.
49 }
50
51 // Note that the code buffer's insts_mark is always relative to insts.
52 // That's why we must use the macroassembler to generate a stub.
53 MacroAssembler _masm(&cbuf);
54
55 address base = __ start_a_stub(to_interp_stub_size());
56 int offset = __ offset();
57 if (base == NULL) {
58 return NULL; // CodeBuffer::expand failed
59 }
60 // static stub relocation stores the instruction address of the call
61 __ relocate(static_stub_Relocation::spec(mark));
62
63 __ emit_static_call_stub();
64
65 assert((__ offset() - offset) <= (int)to_interp_stub_size(), "stub too big");
66 __ end_a_stub();
67 return base;
68 }
69 #undef __
70
71 int CompiledStaticCall::to_interp_stub_size() {
72 // (lui, addi, slli, addi, slli, addi) + (lui, addi, slli, addi, slli) + jalr
73 return 12 * NativeInstruction::instruction_size;
74 }
75
76 int CompiledStaticCall::to_trampoline_stub_size() {
77 // Somewhat pessimistically, we count 4 instructions here (although
78 // there are only 3) because we sometimes emit an alignment nop.
79 // Trampoline stubs are always word aligned.
80 return NativeInstruction::instruction_size + NativeCallTrampolineStub::instruction_size;
81 }
82
83 // Relocation entries for call stub, compiled java to interpreter.
84 int CompiledStaticCall::reloc_to_interp_stub() {
85 return 4; // 3 in emit_to_interp_stub + 1 in emit_call
86 }
87
88 void CompiledDirectStaticCall::set_to_interpreted(const methodHandle& callee, address entry) {
89 address stub = find_stub();
90 guarantee(stub != NULL, "stub not found");
91
92 if (TraceICs) {
93 ResourceMark rm;
94 tty->print_cr("CompiledDirectStaticCall@" INTPTR_FORMAT ": set_to_interpreted %s",
95 p2i(instruction_address()),
96 callee->name_and_sig_as_C_string());
97 }
98
99 // Creation also verifies the object.
100 NativeMovConstReg* method_holder
101 = nativeMovConstReg_at(stub);
102 #ifdef ASSERT
103 NativeGeneralJump* jump = nativeGeneralJump_at(method_holder->next_instruction_address());
104
105 verify_mt_safe(callee, entry, method_holder, jump);
106 #endif
107 // Update stub.
108 method_holder->set_data((intptr_t)callee());
109 NativeGeneralJump::insert_unconditional(method_holder->next_instruction_address(), entry);
110 ICache::invalidate_range(stub, to_interp_stub_size());
111 // Update jump to call.
112 set_destination_mt_safe(stub);
113 }
114
115 void CompiledDirectStaticCall::set_stub_to_clean(static_stub_Relocation* static_stub) {
116 // Reset stub.
117 address stub = static_stub->addr();
118 assert(stub != NULL, "stub not found");
119 assert(CompiledICLocker::is_safe(stub), "mt unsafe call");
120 // Creation also verifies the object.
121 NativeMovConstReg* method_holder
122 = nativeMovConstReg_at(stub);
123 method_holder->set_data(0);
124 NativeJump* jump = nativeJump_at(method_holder->next_instruction_address());
125 jump->set_jump_destination((address)-1);
126 }
127
128 //-----------------------------------------------------------------------------
129 // Non-product mode code
130 #ifndef PRODUCT
131
132 void CompiledDirectStaticCall::verify() {
133 // Verify call.
134 _call->verify();
135 _call->verify_alignment();
136
137 // Verify stub.
138 address stub = find_stub();
139 assert(stub != NULL, "no stub found for static call");
140 // Creation also verifies the object.
141 NativeMovConstReg* method_holder
142 = nativeMovConstReg_at(stub);
143 NativeJump* jump = nativeJump_at(method_holder->next_instruction_address());
144
145 // Verify state.
146 assert(is_clean() || is_call_to_compiled() || is_call_to_interpreted(), "sanity check");
147 }
148
149 #endif // !PRODUCT