1 /*
2 * Copyright (c) 2003, 2021, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2014, Red Hat Inc. All rights reserved.
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 *
24 */
25
26 #include "precompiled.hpp"
27 #include "asm/assembler.inline.hpp"
28 #include "asm/macroAssembler.inline.hpp"
29 #include "code/vtableStubs.hpp"
30 #include "interp_masm_aarch64.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_aarch64.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 // Read "A word on VtableStub sizing" in share/code/vtableStubs.hpp for details on stub sizing.
52 const int stub_code_length = code_size_limit(true);
53 VtableStub* s = new(stub_code_length) VtableStub(true, vtable_index);
54 // Can be NULL if there is no free space in the code cache.
55 if (s == NULL) {
56 return NULL;
57 }
58
59 // Count unused bytes in instruction sequences of variable size.
60 // We add them to the computed buffer size in order to avoid
61 // overflow in subsequently generated stubs.
62 address start_pc;
63 int slop_bytes = 0;
64 int slop_delta = 0;
65
66 ResourceMark rm;
67 CodeBuffer cb(s->entry_point(), stub_code_length);
68 MacroAssembler* masm = new MacroAssembler(&cb);
69
70 #if (!defined(PRODUCT) && defined(COMPILER2))
71 if (CountCompiledCalls) {
72 __ lea(r16, ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));
73 __ increment(Address(r16));
74 }
75 #endif
76
77 // get receiver (need to skip return address on top of stack)
78 assert(VtableStub::receiver_location() == j_rarg0->as_VMReg(), "receiver expected in j_rarg0");
79
80 // get receiver klass
81 address npe_addr = __ pc();
82 __ load_klass(r16, j_rarg0);
83
84 #ifndef PRODUCT
85 if (DebugVtables) {
86 Label L;
87 // TODO: find upper bound for this debug code.
88 start_pc = __ pc();
89
90 // check offset vs vtable length
91 __ ldrw(rscratch1, Address(r16, Klass::vtable_length_offset()));
92 __ cmpw(rscratch1, vtable_index * vtableEntry::size());
93 __ br(Assembler::GT, L);
94 __ enter();
95 __ mov(r2, vtable_index);
96
97 __ call_VM(noreg, CAST_FROM_FN_PTR(address, bad_compiled_vtable_index), j_rarg0, r2);
98 const ptrdiff_t estimate = 256;
99 const ptrdiff_t codesize = __ pc() - start_pc;
100 slop_delta = estimate - codesize; // call_VM varies in length, depending on data
101 slop_bytes += slop_delta;
102 assert(slop_delta >= 0, "vtable #%d: Code size estimate (%d) for DebugVtables too small, required: %d", vtable_index, (int)estimate, (int)codesize);
103
104 __ leave();
105 __ bind(L);
106 }
107 #endif // PRODUCT
108
109 start_pc = __ pc();
110 __ lookup_virtual_method(r16, vtable_index, rmethod);
111 slop_delta = 8 - (int)(__ pc() - start_pc);
112 slop_bytes += slop_delta;
113 assert(slop_delta >= 0, "negative slop(%d) encountered, adjust code size estimate!", slop_delta);
114
115 #ifndef PRODUCT
116 if (DebugVtables) {
117 Label L;
118 __ cbz(rmethod, L);
119 __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));
120 __ cbnz(rscratch1, L);
121 __ stop("Vtable entry is NULL");
122 __ bind(L);
123 }
124 #endif // PRODUCT
125
126 // r0: receiver klass
127 // rmethod: Method*
128 // r2: receiver
129 address ame_addr = __ pc();
130 __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));
131 __ br(rscratch1);
132
133 masm->flush();
134 bookkeeping(masm, tty, s, npe_addr, ame_addr, true, vtable_index, slop_bytes, 0);
135
136 return s;
137 }
138
139
140 VtableStub* VtableStubs::create_itable_stub(int itable_index) {
141 // Read "A word on VtableStub sizing" in share/code/vtableStubs.hpp for details on stub sizing.
142 const int stub_code_length = code_size_limit(false);
143 VtableStub* s = new(stub_code_length) VtableStub(false, itable_index);
144 // Can be NULL if there is no free space in the code cache.
145 if (s == NULL) {
146 return NULL;
147 }
148
149 // Count unused bytes in instruction sequences of variable size.
150 // We add them to the computed buffer size in order to avoid
151 // overflow in subsequently generated stubs.
152 address start_pc;
153 int slop_bytes = 0;
154 int slop_delta = 0;
155
156 ResourceMark rm;
157 CodeBuffer cb(s->entry_point(), stub_code_length);
158 MacroAssembler* masm = new MacroAssembler(&cb);
159
160 #if (!defined(PRODUCT) && defined(COMPILER2))
161 if (CountCompiledCalls) {
162 __ lea(r10, ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));
163 __ increment(Address(r10));
164 }
165 #endif
166
167 // get receiver (need to skip return address on top of stack)
168 assert(VtableStub::receiver_location() == j_rarg0->as_VMReg(), "receiver expected in j_rarg0");
169
170 // Entry arguments:
171 // rscratch2: CompiledICHolder
172 // j_rarg0: Receiver
173
174 // This stub is called from compiled code which has no callee-saved registers,
175 // so all registers except arguments are free at this point.
176 const Register recv_klass_reg = r10;
177 const Register holder_klass_reg = r16; // declaring interface klass (DECC)
178 const Register resolved_klass_reg = rmethod; // resolved interface klass (REFC)
179 const Register temp_reg = r11;
180 const Register temp_reg2 = r15;
181 const Register icholder_reg = rscratch2;
182
183 Label L_no_such_interface;
184
185 __ ldr(resolved_klass_reg, Address(icholder_reg, CompiledICHolder::holder_klass_offset()));
186 __ ldr(holder_klass_reg, Address(icholder_reg, CompiledICHolder::holder_metadata_offset()));
187
188 start_pc = __ pc();
189
190 // get receiver klass (also an implicit null-check)
191 address npe_addr = __ pc();
192 __ load_klass(recv_klass_reg, j_rarg0);
193
194 // Receiver subtype check against REFC.
195 __ lookup_interface_method(// inputs: rec. class, interface
196 recv_klass_reg, resolved_klass_reg, noreg,
197 // outputs: scan temp. reg1, scan temp. reg2
198 temp_reg2, temp_reg,
199 L_no_such_interface,
200 /*return_method=*/false);
201
202 const ptrdiff_t typecheckSize = __ pc() - start_pc;
203 start_pc = __ pc();
204
205 // Get selected method from declaring class and itable index
206 __ lookup_interface_method(// inputs: rec. class, interface, itable index
207 recv_klass_reg, holder_klass_reg, itable_index,
208 // outputs: method, scan temp. reg
209 rmethod, temp_reg,
210 L_no_such_interface);
211
212 const ptrdiff_t lookupSize = __ pc() - start_pc;
213
214 // Reduce "estimate" such that "padding" does not drop below 8.
215 const ptrdiff_t estimate = 124;
216 const ptrdiff_t codesize = typecheckSize + lookupSize;
217 slop_delta = (int)(estimate - codesize);
218 slop_bytes += slop_delta;
219 assert(slop_delta >= 0, "itable #%d: Code size estimate (%d) for lookup_interface_method too small, required: %d", itable_index, (int)estimate, (int)codesize);
220
221 #ifdef ASSERT
222 if (DebugVtables) {
223 Label L2;
224 __ cbz(rmethod, L2);
225 __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));
226 __ cbnz(rscratch1, L2);
227 __ stop("compiler entrypoint is null");
228 __ bind(L2);
229 }
230 #endif // ASSERT
231
232 // rmethod: Method*
233 // j_rarg0: receiver
234 address ame_addr = __ pc();
235 __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));
236 __ br(rscratch1);
237
238 __ bind(L_no_such_interface);
239 // Handle IncompatibleClassChangeError in itable stubs.
240 // More detailed error message.
241 // We force resolving of the call site by jumping to the "handle
242 // wrong method" stub, and so let the interpreter runtime do all the
243 // dirty work.
244 assert(SharedRuntime::get_handle_wrong_method_stub() != NULL, "check initialization order");
245 __ far_jump(RuntimeAddress(SharedRuntime::get_handle_wrong_method_stub()));
246
247 masm->flush();
248 bookkeeping(masm, tty, s, npe_addr, ame_addr, false, itable_index, slop_bytes, 0);
249
250 return s;
251 }
252
253 int VtableStub::pd_code_alignment() {
254 // aarch64 cache line size is not an architected constant. We just align on 4 bytes (instruction size).
255 const unsigned int icache_line_size = 4;
256 return icache_line_size;
257 }