1 /*
2 * Copyright (c) 2003, 2025, 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 "asm/assembler.inline.hpp"
27 #include "asm/macroAssembler.inline.hpp"
28 #include "code/aotCodeCache.hpp"
29 #include "code/compiledIC.hpp"
30 #include "code/vtableStubs.hpp"
31 #include "interp_masm_aarch64.hpp"
32 #include "memory/resourceArea.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, bool caller_is_c1) {
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, caller_is_c1);
54 // Can be null if there is no free space in the code cache.
55 if (s == nullptr) {
56 return nullptr;
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 ByteSize entry_offset = caller_is_c1 ? Method::from_compiled_inline_offset() : Method::from_compiled_inline_ro_offset();
67
68 ResourceMark rm;
69 CodeBuffer cb(s->entry_point(), stub_code_length);
70 MacroAssembler* masm = new MacroAssembler(&cb);
71
72 #if (!defined(PRODUCT) && defined(COMPILER2))
73 if (CountCompiledCalls) {
74 __ lea(r16, ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));
75 __ increment(Address(r16));
76 }
77 #endif
78
79 // get receiver (need to skip return address on top of stack)
80 assert(VtableStub::receiver_location() == j_rarg0->as_VMReg(), "receiver expected in j_rarg0");
81
82 // get receiver klass
83 address npe_addr = __ pc();
84 __ load_klass(r16, j_rarg0);
85
86 #ifndef PRODUCT
87 if (DebugVtables) {
88 Label L;
89 // TODO: find upper bound for this debug code.
90 start_pc = __ pc();
91
92 // check offset vs vtable length
93 __ ldrw(rscratch1, Address(r16, Klass::vtable_length_offset()));
94 __ cmpw(rscratch1, vtable_index * vtableEntry::size());
95 __ br(Assembler::GT, L);
96 __ enter();
97 __ mov(r2, vtable_index);
98
99 __ call_VM(noreg, CAST_FROM_FN_PTR(address, bad_compiled_vtable_index), j_rarg0, r2);
100 const ptrdiff_t estimate = 256;
101 const ptrdiff_t codesize = __ pc() - start_pc;
102 slop_delta = estimate - codesize; // call_VM varies in length, depending on data
103 slop_bytes += slop_delta;
104 assert(slop_delta >= 0, "vtable #%d: Code size estimate (%d) for DebugVtables too small, required: %d", vtable_index, (int)estimate, (int)codesize);
105
106 __ leave();
107 __ bind(L);
108 }
109 #endif // PRODUCT
110
111 start_pc = __ pc();
112 __ lookup_virtual_method(r16, vtable_index, rmethod);
113 slop_delta = 8 - (int)(__ pc() - start_pc);
114 slop_bytes += slop_delta;
115 assert(slop_delta >= 0, "negative slop(%d) encountered, adjust code size estimate!", slop_delta);
116
117 #ifndef PRODUCT
118 if (DebugVtables) {
119 Label L;
120 __ cbz(rmethod, L);
121 __ ldr(rscratch1, Address(rmethod, entry_offset));
122 __ cbnz(rscratch1, L);
123 __ stop("Vtable entry is null");
124 __ bind(L);
125 }
126 #endif // PRODUCT
127
128 // r0: receiver klass
129 // rmethod: Method*
130 // r2: receiver
131 address ame_addr = __ pc();
132 __ ldr(rscratch1, Address(rmethod, entry_offset));
133 __ br(rscratch1);
134
135 masm->flush();
136 bookkeeping(masm, tty, s, npe_addr, ame_addr, true, vtable_index, slop_bytes, 0);
137
138 return s;
139 }
140
141
142 VtableStub* VtableStubs::create_itable_stub(int itable_index, bool caller_is_c1) {
143 // Read "A word on VtableStub sizing" in share/code/vtableStubs.hpp for details on stub sizing.
144 const int stub_code_length = code_size_limit(false);
145 VtableStub* s = new(stub_code_length) VtableStub(false, itable_index, caller_is_c1);
146 // Can be null if there is no free space in the code cache.
147 if (s == nullptr) {
148 return nullptr;
149 }
150
151 // Count unused bytes in instruction sequences of variable size.
152 // We add them to the computed buffer size in order to avoid
153 // overflow in subsequently generated stubs.
154 address start_pc;
155 int slop_bytes = 0;
156 int slop_delta = 0;
157
158 ByteSize entry_offset = caller_is_c1 ? Method::from_compiled_inline_offset() : Method::from_compiled_inline_ro_offset();
159
160 ResourceMark rm;
161 CodeBuffer cb(s->entry_point(), stub_code_length);
162 MacroAssembler* masm = new MacroAssembler(&cb);
163
164 #if (!defined(PRODUCT) && defined(COMPILER2))
165 if (CountCompiledCalls) {
166 __ lea(r10, ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));
167 __ increment(Address(r10));
168 }
169 #endif
170
171 // get receiver (need to skip return address on top of stack)
172 assert(VtableStub::receiver_location() == j_rarg0->as_VMReg(), "receiver expected in j_rarg0");
173
174 // Entry arguments:
175 // rscratch2: CompiledICData
176 // j_rarg0: Receiver
177
178 // This stub is called from compiled code which has no callee-saved registers,
179 // so all registers except arguments are free at this point.
180 const Register recv_klass_reg = r10;
181 const Register holder_klass_reg = r16; // declaring interface klass (DEFC)
182 const Register resolved_klass_reg = r17; // resolved interface klass (REFC)
183 const Register temp_reg = r11;
184 const Register temp_reg2 = r15;
185 const Register icdata_reg = rscratch2;
186
187 Label L_no_such_interface;
188
189 __ ldr(resolved_klass_reg, Address(icdata_reg, CompiledICData::itable_refc_klass_offset()));
190 __ ldr(holder_klass_reg, Address(icdata_reg, CompiledICData::itable_defc_klass_offset()));
191
192 start_pc = __ pc();
193
194 // get receiver klass (also an implicit null-check)
195 address npe_addr = __ pc();
196 __ load_klass(recv_klass_reg, j_rarg0);
197
198 // Receiver subtype check against REFC.
199 // Get selected method from declaring class and itable index
200 __ lookup_interface_method_stub(recv_klass_reg, holder_klass_reg, resolved_klass_reg, rmethod,
201 temp_reg, temp_reg2, itable_index, L_no_such_interface);
202
203 // Reduce "estimate" such that "padding" does not drop below 8.
204 const ptrdiff_t estimate = AOTCodeCache::is_on_for_dump() ? 148 : 144;
205 const ptrdiff_t codesize = __ pc() - start_pc;
206 slop_delta = (int)(estimate - codesize);
207 slop_bytes += slop_delta;
208 assert(slop_delta >= 0, "itable #%d: Code size estimate (%d) for lookup_interface_method too small, required: %d", itable_index, (int)estimate, (int)codesize);
209
210 #ifdef ASSERT
211 if (DebugVtables) {
212 Label L2;
213 __ cbz(rmethod, L2);
214 __ ldr(rscratch1, Address(rmethod, entry_offset));
215 __ cbnz(rscratch1, L2);
216 __ stop("compiler entrypoint is null");
217 __ bind(L2);
218 }
219 #endif // ASSERT
220
221 // rmethod: Method*
222 // j_rarg0: receiver
223 address ame_addr = __ pc();
224 __ ldr(rscratch1, Address(rmethod, entry_offset));
225 __ br(rscratch1);
226
227 __ bind(L_no_such_interface);
228 // Handle IncompatibleClassChangeError in itable stubs.
229 // More detailed error message.
230 // We force resolving of the call site by jumping to the "handle
231 // wrong method" stub, and so let the interpreter runtime do all the
232 // dirty work.
233 assert(SharedRuntime::get_handle_wrong_method_stub() != nullptr, "check initialization order");
234 __ far_jump(RuntimeAddress(SharedRuntime::get_handle_wrong_method_stub()));
235
236 masm->flush();
237 bookkeeping(masm, tty, s, npe_addr, ame_addr, false, itable_index, slop_bytes, 0);
238
239 return s;
240 }
241
242 int VtableStub::pd_code_alignment() {
243 // aarch64 cache line size is not an architected constant. We just align on 4 bytes (instruction size).
244 const unsigned int icache_line_size = 4;
245 return icache_line_size;
246 }