1 /*
2 * Copyright (c) 2008, 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 #include "precompiled.hpp"
26 #include "asm/assembler.hpp"
27 #include "asm/macroAssembler.inline.hpp"
28 #include "assembler_arm.inline.hpp"
29 #include "code/vtableStubs.hpp"
30 #include "interp_masm_arm.hpp"
31 #include "memory/resourceArea.hpp"
32 #include "oops/compiledICHolder.hpp"
33 #include "oops/instanceKlass.hpp"
34 #include "oops/klassVtable.hpp"
35 #include "runtime/sharedRuntime.hpp"
36 #include "vmreg_arm.inline.hpp"
37 #ifdef COMPILER2
38 #include "opto/runtime.hpp"
39 #endif
40
41 // machine-dependent part of VtableStubs: create VtableStub of correct size and
42 // initialize its code
43
44 #define __ masm->
45
46 #ifndef PRODUCT
47 extern "C" void bad_compiled_vtable_index(JavaThread* thread, oop receiver, int index);
48 #endif
49
50 VtableStub* VtableStubs::create_vtable_stub(int vtable_index) {
51 const int code_length = VtableStub::pd_code_size_limit(true);
52 VtableStub* s = new(code_length) VtableStub(true, vtable_index);
53 // Can be NULL if there is no free space in the code cache.
54 if (s == NULL) {
55 return NULL;
56 }
57
58 ResourceMark rm;
59 CodeBuffer cb(s->entry_point(), code_length);
60 MacroAssembler* masm = new MacroAssembler(&cb);
61
62 assert(VtableStub::receiver_location() == R0->as_VMReg(), "receiver expected in R0");
63
64 const Register tmp = Rtemp; // Rtemp OK, should be free at call sites
65
66 address npe_addr = __ pc();
67 __ load_klass(tmp, R0);
68
69 {
70 int entry_offset = in_bytes(Klass::vtable_start_offset()) + vtable_index * vtableEntry::size_in_bytes();
71 int method_offset = vtableEntry::method_offset_in_bytes() + entry_offset;
72
73 assert ((method_offset & (wordSize - 1)) == 0, "offset should be aligned");
74 int offset_mask = AARCH64_ONLY(0xfff << LogBytesPerWord) NOT_AARCH64(0xfff);
75 if (method_offset & ~offset_mask) {
76 __ add(tmp, tmp, method_offset & ~offset_mask);
77 }
78 __ ldr(Rmethod, Address(tmp, method_offset & offset_mask));
79 }
80
81 address ame_addr = __ pc();
82 #ifdef AARCH64
83 __ ldr(tmp, Address(Rmethod, Method::from_compiled_offset()));
84 __ br(tmp);
85 #else
86 __ ldr(PC, Address(Rmethod, Method::from_compiled_offset()));
87 #endif // AARCH64
88
89 masm->flush();
90
91 if (PrintMiscellaneous && (WizardMode || Verbose)) {
92 tty->print_cr("vtable #%d at " PTR_FORMAT "[%d] left over: %d",
93 vtable_index, p2i(s->entry_point()),
94 (int)(s->code_end() - s->entry_point()),
95 (int)(s->code_end() - __ pc()));
96 }
97 guarantee(__ pc() <= s->code_end(), "overflowed buffer");
98 // FIXME ARM: need correct 'slop' - below is x86 code
99 // shut the door on sizing bugs
100 //int slop = 8; // 32-bit offset is this much larger than a 13-bit one
101 //assert(vtable_index > 10 || __ pc() + slop <= s->code_end(), "room for 32-bit offset");
102
103 s->set_exception_points(npe_addr, ame_addr);
104 return s;
105 }
106
107 VtableStub* VtableStubs::create_itable_stub(int itable_index) {
108 const int code_length = VtableStub::pd_code_size_limit(false);
109 VtableStub* s = new(code_length) VtableStub(false, itable_index);
110 // Can be NULL if there is no free space in the code cache.
111 if (s == NULL) {
112 return NULL;
113 }
114
115 ResourceMark rm;
116 CodeBuffer cb(s->entry_point(), code_length);
117 MacroAssembler* masm = new MacroAssembler(&cb);
118
119 assert(VtableStub::receiver_location() == R0->as_VMReg(), "receiver expected in R0");
120
121 // R0-R3 / R0-R7 registers hold the arguments and cannot be spoiled
122 const Register Rclass = AARCH64_ONLY(R9) NOT_AARCH64(R4);
123 const Register Rintf = AARCH64_ONLY(R10) NOT_AARCH64(R5);
124 const Register Rscan = AARCH64_ONLY(R11) NOT_AARCH64(R6);
125
126 assert_different_registers(Ricklass, Rclass, Rintf, Rscan, Rtemp);
127
128 // Calculate the start of itable (itable goes after vtable)
129 const int scale = exact_log2(vtableEntry::size_in_bytes());
130 address npe_addr = __ pc();
131 __ load_klass(Rclass, R0);
132
133 Label L_no_such_interface;
134
135 // Receiver subtype check against REFC.
136 __ ldr(Rintf, Address(Ricklass, CompiledICHolder::holder_klass_offset()));
137 __ lookup_interface_method(// inputs: rec. class, interface, itable index
138 Rclass, Rintf, noreg,
139 // outputs: temp reg1, temp reg2
140 noreg, Rscan, Rtemp,
141 L_no_such_interface);
142
143 // Get Method* and entry point for compiler
144 __ ldr(Rintf, Address(Ricklass, CompiledICHolder::holder_metadata_offset()));
145 __ lookup_interface_method(// inputs: rec. class, interface, itable index
146 Rclass, Rintf, itable_index,
147 // outputs: temp reg1, temp reg2, temp reg3
148 Rmethod, Rscan, Rtemp,
149 L_no_such_interface);
150
151 address ame_addr = __ pc();
152
153 #ifdef AARCH64
154 __ ldr(Rtemp, Address(Rmethod, Method::from_compiled_offset()));
155 __ br(Rtemp);
156 #else
157 __ ldr(PC, Address(Rmethod, Method::from_compiled_offset()));
158 #endif // AARCH64
159
160 __ bind(L_no_such_interface);
161
162 // Handle IncompatibleClassChangeError in itable stubs.
163 // More detailed error message.
164 // We force resolving of the call site by jumping to the "handle
165 // wrong method" stub, and so let the interpreter runtime do all the
166 // dirty work.
167 assert(SharedRuntime::get_handle_wrong_method_stub() != NULL, "check initialization order");
168 __ jump(SharedRuntime::get_handle_wrong_method_stub(), relocInfo::runtime_call_type, Rtemp);
169
170 masm->flush();
171
172 if (PrintMiscellaneous && (WizardMode || Verbose)) {
173 tty->print_cr("itable #%d at " PTR_FORMAT "[%d] left over: %d",
174 itable_index, p2i(s->entry_point()),
175 (int)(s->code_end() - s->entry_point()),
176 (int)(s->code_end() - __ pc()));
177 }
178 guarantee(__ pc() <= s->code_end(), "overflowed buffer");
179 // FIXME ARM: need correct 'slop' - below is x86 code
180 // shut the door on sizing bugs
181 //int slop = 8; // 32-bit offset is this much larger than a 13-bit one
182 //assert(itable_index > 10 || __ pc() + slop <= s->code_end(), "room for 32-bit offset");
183
184 s->set_exception_points(npe_addr, ame_addr);
185 return s;
186 }
187
188 int VtableStub::pd_code_size_limit(bool is_vtable_stub) {
189 int instr_count;
190
191 if (is_vtable_stub) {
192 // vtable stub size
193 instr_count = NOT_AARCH64(4) AARCH64_ONLY(5);
194 } else {
195 // itable stub size
196 instr_count = NOT_AARCH64(31) AARCH64_ONLY(31);
197 }
198
199 #ifdef AARCH64
200 if (UseCompressedClassPointers) {
201 instr_count += MacroAssembler::instr_count_for_decode_klass_not_null();
202 }
203 #endif // AARCH64
204
205 return instr_count * Assembler::InstructionSize;
206 }
207
208 int VtableStub::pd_code_alignment() {
209 return 8;
210 }