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 }