1 /*
2 * Copyright (c) 2003, 2018, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2014, Red Hat Inc. All rights reserved.
4 * Copyright (c) 2020, 2022, 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 "assembler_riscv.inline.hpp"
30 #include "code/vtableStubs.hpp"
31 #include "interp_masm_riscv.hpp"
32 #include "memory/resourceArea.hpp"
33 #include "oops/compiledICHolder.hpp"
34 #include "oops/instanceKlass.hpp"
35 #include "oops/klassVtable.hpp"
36 #include "runtime/sharedRuntime.hpp"
37 #include "vmreg_riscv.inline.hpp"
38 #ifdef COMPILER2
39 #include "opto/runtime.hpp"
40 #endif
41
42 // machine-dependent part of VtableStubs: create VtableStub of correct size and
43 // initialize its code
44
45 #define __ masm->
46
47 #ifndef PRODUCT
48 extern "C" void bad_compiled_vtable_index(JavaThread* thread, oop receiver, int index);
49 #endif
50
51 VtableStub* VtableStubs::create_vtable_stub(int vtable_index) {
52 // Read "A word on VtableStub sizing" in share/code/vtableStubs.hpp for details on stub sizing.
53 const int stub_code_length = code_size_limit(true);
54 VtableStub* s = new(stub_code_length) VtableStub(true, vtable_index);
55 // Can be NULL if there is no free space in the code cache.
56 if (s == NULL) {
57 return NULL;
58 }
59
60 // Count unused bytes in instruction sequences of variable size.
61 // We add them to the computed buffer size in order to avoid
62 // overflow in subsequently generated stubs.
63 address start_pc = NULL;
64 int slop_bytes = 0;
65 int slop_delta = 0;
66
67 ResourceMark rm;
68 CodeBuffer cb(s->entry_point(), stub_code_length);
69 MacroAssembler* masm = new MacroAssembler(&cb);
70 assert_cond(masm != NULL);
71
72 #if (!defined(PRODUCT) && defined(COMPILER2))
73 if (CountCompiledCalls) {
74 __ la(t2, ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));
75 __ add_memory_int64(Address(t2), 1);
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(t2, j_rarg0);
85
86 #ifndef PRODUCT
87 if (DebugVtables) {
88 Label L;
89 start_pc = __ pc();
90
91 // check offset vs vtable length
92 __ lwu(t0, Address(t2, Klass::vtable_length_offset()));
93 __ mvw(t1, vtable_index * vtableEntry::size());
94 __ bgt(t0, t1, L);
95 __ enter();
96 __ mv(x12, vtable_index);
97
98 __ call_VM(noreg, CAST_FROM_FN_PTR(address, bad_compiled_vtable_index), j_rarg0, x12);
99 const ptrdiff_t estimate = 256;
100 const ptrdiff_t codesize = __ pc() - start_pc;
101 slop_delta = estimate - codesize; // call_VM varies in length, depending on data
102 slop_bytes += slop_delta;
103 assert(slop_delta >= 0, "vtable #%d: Code size estimate (%d) for DebugVtables too small, required: %d", vtable_index, (int)estimate, (int)codesize);
104
105 __ leave();
106 __ bind(L);
107 }
108 #endif // PRODUCT
109
110 start_pc = __ pc();
111 __ lookup_virtual_method(t2, vtable_index, xmethod);
112 // lookup_virtual_method generates
113 // 4 instructions (maximum value encountered in normal case):li(lui + addiw) + add + ld
114 // 1 instruction (best case):ld * 1
115 slop_delta = 16 - (int)(__ pc() - start_pc);
116 slop_bytes += slop_delta;
117 assert(slop_delta >= 0, "negative slop(%d) encountered, adjust code size estimate!", slop_delta);
118
119 #ifndef PRODUCT
120 if (DebugVtables) {
121 Label L;
122 __ beqz(xmethod, L);
123 __ ld(t0, Address(xmethod, Method::from_compiled_offset()));
124 __ bnez(t0, L);
125 __ stop("Vtable entry is NULL");
126 __ bind(L);
127 }
128 #endif // PRODUCT
129
130 // x10: receiver klass
131 // xmethod: Method*
132 // x12: receiver
133 address ame_addr = __ pc();
134 __ ld(t0, Address(xmethod, Method::from_compiled_offset()));
135 __ jr(t0);
136
137 masm->flush();
138 bookkeeping(masm, tty, s, npe_addr, ame_addr, true, vtable_index, slop_bytes, 0);
139
140 return s;
141 }
142
143 VtableStub* VtableStubs::create_itable_stub(int itable_index) {
144 // Read "A word on VtableStub sizing" in share/code/vtableStubs.hpp for details on stub sizing.
145 const int stub_code_length = code_size_limit(false);
146 VtableStub* s = new(stub_code_length) VtableStub(false, itable_index);
147 // Can be NULL if there is no free space in the code cache.
148 if (s == NULL) {
149 return NULL;
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 = NULL;
155 int slop_bytes = 0;
156 int slop_delta = 0;
157
158 ResourceMark rm;
159 CodeBuffer cb(s->entry_point(), stub_code_length);
160 MacroAssembler* masm = new MacroAssembler(&cb);
161 assert_cond(masm != NULL);
162
163 #if (!defined(PRODUCT) && defined(COMPILER2))
164 if (CountCompiledCalls) {
165 __ la(x18, ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));
166 __ add_memory_int64(Address(x18), 1);
167 }
168 #endif
169
170 // get receiver (need to skip return address on top of stack)
171 assert(VtableStub::receiver_location() == j_rarg0->as_VMReg(), "receiver expected in j_rarg0");
172
173 // Entry arguments:
174 // t1: CompiledICHolder
175 // j_rarg0: Receiver
176
177 // This stub is called from compiled code which has no callee-saved registers,
178 // so all registers except arguments are free at this point.
179 const Register recv_klass_reg = x18;
180 const Register holder_klass_reg = x19; // declaring interface klass (DECC)
181 const Register resolved_klass_reg = xmethod; // resolved interface klass (REFC)
182 const Register temp_reg = x28;
183 const Register temp_reg2 = x29;
184 const Register icholder_reg = t1;
185
186 Label L_no_such_interface;
187
188 __ ld(resolved_klass_reg, Address(icholder_reg, CompiledICHolder::holder_klass_offset()));
189 __ ld(holder_klass_reg, Address(icholder_reg, CompiledICHolder::holder_metadata_offset()));
190
191 start_pc = __ pc();
192
193 // get receiver klass (also an implicit null-check)
194 address npe_addr = __ pc();
195 __ load_klass(recv_klass_reg, j_rarg0);
196
197 // Receiver subtype check against REFC.
198 __ lookup_interface_method(// inputs: rec. class, interface
199 recv_klass_reg, resolved_klass_reg, noreg,
200 // outputs: scan temp. reg1, scan temp. reg2
201 temp_reg2, temp_reg,
202 L_no_such_interface,
203 /*return_method=*/false);
204
205 const ptrdiff_t typecheckSize = __ pc() - start_pc;
206 start_pc = __ pc();
207
208 // Get selected method from declaring class and itable index
209 __ lookup_interface_method(// inputs: rec. class, interface, itable index
210 recv_klass_reg, holder_klass_reg, itable_index,
211 // outputs: method, scan temp. reg
212 xmethod, temp_reg,
213 L_no_such_interface);
214
215 const ptrdiff_t lookupSize = __ pc() - start_pc;
216
217 // Reduce "estimate" such that "padding" does not drop below 8.
218 const ptrdiff_t estimate = 256;
219 const ptrdiff_t codesize = typecheckSize + lookupSize;
220 slop_delta = (int)(estimate - codesize);
221 slop_bytes += slop_delta;
222 assert(slop_delta >= 0, "itable #%d: Code size estimate (%d) for lookup_interface_method too small, required: %d", itable_index, (int)estimate, (int)codesize);
223
224 #ifdef ASSERT
225 if (DebugVtables) {
226 Label L2;
227 __ beqz(xmethod, L2);
228 __ ld(t0, Address(xmethod, Method::from_compiled_offset()));
229 __ bnez(t0, L2);
230 __ stop("compiler entrypoint is null");
231 __ bind(L2);
232 }
233 #endif // ASSERT
234
235 // xmethod: Method*
236 // j_rarg0: receiver
237 address ame_addr = __ pc();
238 __ ld(t0, Address(xmethod, Method::from_compiled_offset()));
239 __ jr(t0);
240
241 __ bind(L_no_such_interface);
242 // Handle IncompatibleClassChangeError in itable stubs.
243 // More detailed error message.
244 // We force resolving of the call site by jumping to the "handle
245 // wrong method" stub, and so let the interpreter runtime do all the
246 // dirty work.
247 assert(SharedRuntime::get_handle_wrong_method_stub() != NULL, "check initialization order");
248 __ far_jump(RuntimeAddress(SharedRuntime::get_handle_wrong_method_stub()));
249
250 masm->flush();
251 bookkeeping(masm, tty, s, npe_addr, ame_addr, false, itable_index, slop_bytes, 0);
252
253 return s;
254 }
255
256 int VtableStub::pd_code_alignment() {
257 // RISCV cache line size is not an architected constant. We just align on word size.
258 const unsigned int icache_line_size = wordSize;
259 return icache_line_size;
260 }