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/compiledIC.hpp" 29 #include "code/vtableStubs.hpp" 30 #include "interp_masm_aarch64.hpp" 31 #include "memory/resourceArea.hpp" 32 #include "oops/instanceKlass.hpp" 33 #include "oops/klassVtable.hpp" 34 #include "runtime/sharedRuntime.hpp" 35 #include "vmreg_aarch64.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 // Read "A word on VtableStub sizing" in share/code/vtableStubs.hpp for details on stub sizing. 51 const int stub_code_length = code_size_limit(true); 52 VtableStub* s = new(stub_code_length) VtableStub(true, vtable_index); 53 // Can be null if there is no free space in the code cache. 54 if (s == nullptr) { 55 return nullptr; 56 } 57 58 // Count unused bytes in instruction sequences of variable size. 59 // We add them to the computed buffer size in order to avoid 60 // overflow in subsequently generated stubs. 61 address start_pc; 62 int slop_bytes = 0; 63 int slop_delta = 0; 64 65 ResourceMark rm; 66 CodeBuffer cb(s->entry_point(), stub_code_length); 67 MacroAssembler* masm = new MacroAssembler(&cb); 68 69 #if (!defined(PRODUCT) && defined(COMPILER2)) 70 if (CountCompiledCalls) { 71 __ lea(r16, ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr())); 72 __ increment(Address(r16)); 73 } 74 #endif 75 76 // get receiver (need to skip return address on top of stack) 77 assert(VtableStub::receiver_location() == j_rarg0->as_VMReg(), "receiver expected in j_rarg0"); 78 79 // get receiver klass 80 address npe_addr = __ pc(); 81 __ load_klass(r16, j_rarg0); 82 83 #ifndef PRODUCT 84 if (DebugVtables) { 85 Label L; 86 // TODO: find upper bound for this debug code. 87 start_pc = __ pc(); 88 89 // check offset vs vtable length 90 __ ldrw(rscratch1, Address(r16, Klass::vtable_length_offset())); 91 __ cmpw(rscratch1, vtable_index * vtableEntry::size()); 92 __ br(Assembler::GT, L); 93 __ enter(); 94 __ mov(r2, vtable_index); 95 96 __ call_VM(noreg, CAST_FROM_FN_PTR(address, bad_compiled_vtable_index), j_rarg0, r2); 97 const ptrdiff_t estimate = 256; 98 const ptrdiff_t codesize = __ pc() - start_pc; 99 slop_delta = estimate - codesize; // call_VM varies in length, depending on data 100 slop_bytes += slop_delta; 101 assert(slop_delta >= 0, "vtable #%d: Code size estimate (%d) for DebugVtables too small, required: %d", vtable_index, (int)estimate, (int)codesize); 102 103 __ leave(); 104 __ bind(L); 105 } 106 #endif // PRODUCT 107 108 start_pc = __ pc(); 109 __ lookup_virtual_method(r16, vtable_index, rmethod); 110 slop_delta = 8 - (int)(__ pc() - start_pc); 111 slop_bytes += slop_delta; 112 assert(slop_delta >= 0, "negative slop(%d) encountered, adjust code size estimate!", slop_delta); 113 114 #ifndef PRODUCT 115 if (DebugVtables) { 116 Label L; 117 __ cbz(rmethod, L); 118 __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset())); 119 __ cbnz(rscratch1, L); 120 __ stop("Vtable entry is null"); 121 __ bind(L); 122 } 123 #endif // PRODUCT 124 125 // r0: receiver klass 126 // rmethod: Method* 127 // r2: receiver 128 address ame_addr = __ pc(); 129 __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset())); 130 __ br(rscratch1); 131 132 masm->flush(); 133 bookkeeping(masm, tty, s, npe_addr, ame_addr, true, vtable_index, slop_bytes, 0); 134 135 return s; 136 } 137 138 139 VtableStub* VtableStubs::create_itable_stub(int itable_index) { 140 // Read "A word on VtableStub sizing" in share/code/vtableStubs.hpp for details on stub sizing. 141 const int stub_code_length = code_size_limit(false); 142 VtableStub* s = new(stub_code_length) VtableStub(false, itable_index); 143 // Can be null if there is no free space in the code cache. 144 if (s == nullptr) { 145 return nullptr; 146 } 147 148 // Count unused bytes in instruction sequences of variable size. 149 // We add them to the computed buffer size in order to avoid 150 // overflow in subsequently generated stubs. 151 address start_pc; 152 int slop_bytes = 0; 153 int slop_delta = 0; 154 155 ResourceMark rm; 156 CodeBuffer cb(s->entry_point(), stub_code_length); 157 MacroAssembler* masm = new MacroAssembler(&cb); 158 159 #if (!defined(PRODUCT) && defined(COMPILER2)) 160 if (CountCompiledCalls) { 161 __ lea(r10, ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr())); 162 __ increment(Address(r10)); 163 } 164 #endif 165 166 // get receiver (need to skip return address on top of stack) 167 assert(VtableStub::receiver_location() == j_rarg0->as_VMReg(), "receiver expected in j_rarg0"); 168 169 // Entry arguments: 170 // rscratch2: CompiledICData 171 // j_rarg0: Receiver 172 173 // This stub is called from compiled code which has no callee-saved registers, 174 // so all registers except arguments are free at this point. 175 const Register recv_klass_reg = r10; 176 const Register holder_klass_reg = r16; // declaring interface klass (DEFC) 177 const Register resolved_klass_reg = r17; // resolved interface klass (REFC) 178 const Register temp_reg = r11; 179 const Register temp_reg2 = r15; 180 const Register icdata_reg = rscratch2; 181 182 Label L_no_such_interface; 183 184 __ ldr(resolved_klass_reg, Address(icdata_reg, CompiledICData::itable_refc_klass_offset())); 185 __ ldr(holder_klass_reg, Address(icdata_reg, CompiledICData::itable_defc_klass_offset())); 186 187 start_pc = __ pc(); 188 189 // get receiver klass (also an implicit null-check) 190 address npe_addr = __ pc(); 191 __ load_klass(recv_klass_reg, j_rarg0); 192 193 // Receiver subtype check against REFC. 194 // Get selected method from declaring class and itable index 195 __ lookup_interface_method_stub(recv_klass_reg, holder_klass_reg, resolved_klass_reg, rmethod, 196 temp_reg, temp_reg2, itable_index, L_no_such_interface); 197 198 // Reduce "estimate" such that "padding" does not drop below 8. 199 const ptrdiff_t estimate = 144; 200 const ptrdiff_t codesize = __ pc() - start_pc; 201 slop_delta = (int)(estimate - codesize); 202 slop_bytes += slop_delta; 203 assert(slop_delta >= 0, "itable #%d: Code size estimate (%d) for lookup_interface_method too small, required: %d", itable_index, (int)estimate, (int)codesize); 204 205 #ifdef ASSERT 206 if (DebugVtables) { 207 Label L2; 208 __ cbz(rmethod, L2); 209 __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset())); 210 __ cbnz(rscratch1, L2); 211 __ stop("compiler entrypoint is null"); 212 __ bind(L2); 213 } 214 #endif // ASSERT 215 216 // rmethod: Method* 217 // j_rarg0: receiver 218 address ame_addr = __ pc(); 219 __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset())); 220 __ br(rscratch1); 221 222 __ bind(L_no_such_interface); 223 // Handle IncompatibleClassChangeError in itable stubs. 224 // More detailed error message. 225 // We force resolving of the call site by jumping to the "handle 226 // wrong method" stub, and so let the interpreter runtime do all the 227 // dirty work. 228 assert(SharedRuntime::get_handle_wrong_method_stub() != nullptr, "check initialization order"); 229 __ far_jump(RuntimeAddress(SharedRuntime::get_handle_wrong_method_stub())); 230 231 masm->flush(); 232 bookkeeping(masm, tty, s, npe_addr, ame_addr, false, itable_index, slop_bytes, 0); 233 234 return s; 235 } 236 237 int VtableStub::pd_code_alignment() { 238 // aarch64 cache line size is not an architected constant. We just align on 4 bytes (instruction size). 239 const unsigned int icache_line_size = 4; 240 return icache_line_size; 241 }