1 /*
2 * Copyright (c) 2008, 2016, 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 "assembler_arm.inline.hpp"
28 #include "code/vtableStubs.hpp"
29 #include "interp_masm_arm.hpp"
30 #include "memory/resourceArea.hpp"
31 #include "oops/compiledICHolder.hpp"
32 #include "oops/instanceKlass.hpp"
33 #include "oops/klassVtable.hpp"
34 #include "runtime/sharedRuntime.hpp"
35 #include "vmreg_arm.inline.hpp"
36 #ifdef COMPILER2
37 #include "opto/runtime.hpp"
38 #endif
39
40 // machine-dependent part of VtableStubs: create VtableStub of correct size and
41 // initialize its code
42
43 #define __ masm->
44
45 #ifndef PRODUCT
46 extern "C" void bad_compiled_vtable_index(JavaThread* thread, oop receiver, int index);
47 #endif
48
49 VtableStub* VtableStubs::create_vtable_stub(int vtable_index) {
50 const int code_length = VtableStub::pd_code_size_limit(true);
51 VtableStub* s = new(code_length) VtableStub(true, vtable_index);
52 // Can be NULL if there is no free space in the code cache.
53 if (s == NULL) {
54 return NULL;
55 }
56
57 ResourceMark rm;
58 CodeBuffer cb(s->entry_point(), code_length);
59 MacroAssembler* masm = new MacroAssembler(&cb);
60
61 assert(VtableStub::receiver_location() == R0->as_VMReg(), "receiver expected in R0");
62
63 const Register tmp = Rtemp; // Rtemp OK, should be free at call sites
64
65 address npe_addr = __ pc();
66 __ load_klass(tmp, R0);
67
68 {
69 int entry_offset = in_bytes(Klass::vtable_start_offset()) + vtable_index * vtableEntry::size_in_bytes();
70 int method_offset = vtableEntry::method_offset_in_bytes() + entry_offset;
71
72 assert ((method_offset & (wordSize - 1)) == 0, "offset should be aligned");
73 int offset_mask = AARCH64_ONLY(0xfff << LogBytesPerWord) NOT_AARCH64(0xfff);
74 if (method_offset & ~offset_mask) {
75 __ add(tmp, tmp, method_offset & ~offset_mask);
76 }
77 __ ldr(Rmethod, Address(tmp, method_offset & offset_mask));
78 }
79
80 address ame_addr = __ pc();
81 #ifdef AARCH64
82 __ ldr(tmp, Address(Rmethod, Method::from_compiled_offset()));
83 __ br(tmp);
84 #else
85 __ ldr(PC, Address(Rmethod, Method::from_compiled_offset()));
86 #endif // AARCH64
87
88 masm->flush();
89
90 if (PrintMiscellaneous && (WizardMode || Verbose)) {
91 tty->print_cr("vtable #%d at " PTR_FORMAT "[%d] left over: %d",
92 vtable_index, p2i(s->entry_point()),
93 (int)(s->code_end() - s->entry_point()),
94 (int)(s->code_end() - __ pc()));
95 }
96 guarantee(__ pc() <= s->code_end(), "overflowed buffer");
97 // FIXME ARM: need correct 'slop' - below is x86 code
98 // shut the door on sizing bugs
99 //int slop = 8; // 32-bit offset is this much larger than a 13-bit one
100 //assert(vtable_index > 10 || __ pc() + slop <= s->code_end(), "room for 32-bit offset");
101
102 s->set_exception_points(npe_addr, ame_addr);
103 return s;
104 }
105
106 VtableStub* VtableStubs::create_itable_stub(int itable_index) {
107 const int code_length = VtableStub::pd_code_size_limit(false);
108 VtableStub* s = new(code_length) VtableStub(false, itable_index);
109 // Can be NULL if there is no free space in the code cache.
110 if (s == NULL) {
111 return NULL;
112 }
113
114 ResourceMark rm;
115 CodeBuffer cb(s->entry_point(), code_length);
116 MacroAssembler* masm = new MacroAssembler(&cb);
117
118 assert(VtableStub::receiver_location() == R0->as_VMReg(), "receiver expected in R0");
119
120 // R0-R3 / R0-R7 registers hold the arguments and cannot be spoiled
121 const Register Rclass = AARCH64_ONLY(R9) NOT_AARCH64(R4);
122 const Register Rintf = AARCH64_ONLY(R10) NOT_AARCH64(R5);
123 const Register Rscan = AARCH64_ONLY(R11) NOT_AARCH64(R6);
124
125 assert_different_registers(Ricklass, Rclass, Rintf, Rscan, Rtemp);
126
127 // Calculate the start of itable (itable goes after vtable)
128 const int scale = exact_log2(vtableEntry::size_in_bytes());
129 address npe_addr = __ pc();
130 __ load_klass(Rclass, R0);
131
132 Label L_no_such_interface;
133
134 // Receiver subtype check against REFC.
135 __ ldr(Rintf, Address(Ricklass, CompiledICHolder::holder_klass_offset()));
136 __ lookup_interface_method(// inputs: rec. class, interface, itable index
137 Rclass, Rintf, noreg,
138 // outputs: temp reg1, temp reg2
139 noreg, Rscan, Rtemp,
140 L_no_such_interface);
141
142 // Get Method* and entry point for compiler
143 __ ldr(Rintf, Address(Ricklass, CompiledICHolder::holder_metadata_offset()));
144 __ lookup_interface_method(// inputs: rec. class, interface, itable index
145 Rclass, Rintf, itable_index,
146 // outputs: temp reg1, temp reg2, temp reg3
147 Rmethod, Rscan, Rtemp,
148 L_no_such_interface);
149
150 address ame_addr = __ pc();
151
152 #ifdef AARCH64
153 __ ldr(Rtemp, Address(Rmethod, Method::from_compiled_offset()));
154 __ br(Rtemp);
155 #else
156 __ ldr(PC, Address(Rmethod, Method::from_compiled_offset()));
157 #endif // AARCH64
158
159 __ bind(L_no_such_interface);
160
161 assert(StubRoutines::throw_IncompatibleClassChangeError_entry() != NULL, "check initialization order");
162 __ jump(StubRoutines::throw_IncompatibleClassChangeError_entry(), relocInfo::runtime_call_type, Rtemp);
163
164 masm->flush();
165
166 if (PrintMiscellaneous && (WizardMode || Verbose)) {
167 tty->print_cr("itable #%d at " PTR_FORMAT "[%d] left over: %d",
168 itable_index, p2i(s->entry_point()),
169 (int)(s->code_end() - s->entry_point()),
170 (int)(s->code_end() - __ pc()));
171 }
172 guarantee(__ pc() <= s->code_end(), "overflowed buffer");
173 // FIXME ARM: need correct 'slop' - below is x86 code
174 // shut the door on sizing bugs
175 //int slop = 8; // 32-bit offset is this much larger than a 13-bit one
176 //assert(itable_index > 10 || __ pc() + slop <= s->code_end(), "room for 32-bit offset");
177
178 s->set_exception_points(npe_addr, ame_addr);
179 return s;
180 }
181
182 int VtableStub::pd_code_size_limit(bool is_vtable_stub) {
183 int instr_count;
184
185 if (is_vtable_stub) {
186 // vtable stub size
187 instr_count = NOT_AARCH64(4) AARCH64_ONLY(5);
188 } else {
189 // itable stub size
190 instr_count = NOT_AARCH64(31) AARCH64_ONLY(31);
191 }
192
193 #ifdef AARCH64
194 if (UseCompressedClassPointers) {
195 instr_count += MacroAssembler::instr_count_for_decode_klass_not_null();
196 }
197 #endif // AARCH64
198
199 return instr_count * Assembler::InstructionSize;
200 }
201
202 int VtableStub::pd_code_alignment() {
203 return 8;
204 }