1 /* 2 * Copyright (c) 2004, 2026, Oracle and/or its affiliates. All rights reserved. 3 * Copyright (c) 2014, 2020, Red Hat Inc. All rights reserved. 4 * Copyright (c) 2020, 2023, 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 "asm/macroAssembler.hpp" 28 #include "gc/shared/barrierSet.hpp" 29 #include "gc/shared/barrierSetAssembler.hpp" 30 #include "memory/resourceArea.hpp" 31 #include "prims/jniFastGetField.hpp" 32 #include "prims/jvm_misc.hpp" 33 #include "prims/jvmtiExport.hpp" 34 #include "runtime/jfieldIDWorkaround.hpp" 35 #include "runtime/safepoint.hpp" 36 37 #define __ masm-> 38 39 #define BUFFER_SIZE 30*wordSize 40 41 // Instead of issuing a LoadLoad barrier we create an address 42 // dependency between loads; this might be more efficient. 43 44 // Common register usage: 45 // x10/f10: result 46 // c_rarg0: jni env 47 // c_rarg1: obj 48 // c_rarg2: jfield id 49 50 static const Register robj = x13; 51 static const Register rcounter = x14; 52 static const Register roffset = x15; 53 static const Register rcounter_addr = x16; 54 static const Register result = x17; 55 56 address JNI_FastGetField::generate_fast_get_int_field0(BasicType type) { 57 const char *name; 58 switch (type) { 59 case T_BOOLEAN: name = "jni_fast_GetBooleanField"; break; 60 case T_BYTE: name = "jni_fast_GetByteField"; break; 61 case T_CHAR: name = "jni_fast_GetCharField"; break; 62 case T_SHORT: name = "jni_fast_GetShortField"; break; 63 case T_INT: name = "jni_fast_GetIntField"; break; 64 case T_LONG: name = "jni_fast_GetLongField"; break; 65 case T_FLOAT: name = "jni_fast_GetFloatField"; break; 66 case T_DOUBLE: name = "jni_fast_GetDoubleField"; break; 67 default: ShouldNotReachHere(); 68 name = nullptr; // unreachable 69 } 70 ResourceMark rm; 71 BufferBlob* blob = BufferBlob::create(name, BUFFER_SIZE); 72 CodeBuffer cbuf(blob); 73 MacroAssembler* masm = new MacroAssembler(&cbuf); 74 address fast_entry = __ pc(); 75 76 Label slow; 77 ExternalAddress counter(SafepointSynchronize::safepoint_counter_addr()); 78 __ la(rcounter_addr, counter); 79 __ lwu(rcounter, Address(rcounter_addr)); 80 // An even value means there are no ongoing safepoint operations 81 __ test_bit(t0, rcounter, 0); 82 __ bnez(t0, slow); 83 84 if (JvmtiExport::can_post_field_access()) { 85 // Using barrier to order wrt. JVMTI check and load of result. 86 __ membar(MacroAssembler::LoadLoad); 87 88 // Check to see if a field access watch has been set before we 89 // take the fast path. 90 __ lwu(result, ExternalAddress(JvmtiExport::get_field_access_count_addr())); 91 __ bnez(result, slow); 92 93 __ mv(robj, c_rarg1); 94 } else { 95 // Using address dependency to order wrt. load of result. 96 __ xorr(robj, c_rarg1, rcounter); 97 __ xorr(robj, robj, rcounter); // obj, since 98 // robj ^ rcounter ^ rcounter == robj 99 // robj is address dependent on rcounter. 100 } 101 102 // Both robj and t0 are clobbered by try_resolve_jobject_in_native. 103 BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler(); 104 assert_cond(bs != nullptr); 105 bs->try_resolve_jobject_in_native(masm, c_rarg0, robj, t0, slow); 106 107 __ srli(roffset, c_rarg2, jfieldIDWorkaround::offset_shift); // offset 108 109 assert(count < LIST_CAPACITY, "LIST_CAPACITY too small"); 110 speculative_load_pclist[count] = __ pc(); // Used by the segfault handler 111 __ add(roffset, robj, roffset); 112 113 switch (type) { 114 case T_BOOLEAN: __ lbu(result, Address(roffset, 0)); break; 115 case T_BYTE: __ lb(result, Address(roffset, 0)); break; 116 case T_CHAR: __ lhu(result, Address(roffset, 0)); break; 117 case T_SHORT: __ lh(result, Address(roffset, 0)); break; 118 case T_INT: __ lw(result, Address(roffset, 0)); break; 119 case T_LONG: __ ld(result, Address(roffset, 0)); break; 120 case T_FLOAT: { 121 __ flw(f28, Address(roffset, 0)); // f28 as temporaries 122 __ fmv_x_w(result, f28); // f{31--0}-->x 123 break; 124 } 125 case T_DOUBLE: { 126 __ fld(f28, Address(roffset, 0)); // f28 as temporaries 127 __ fmv_x_d(result, f28); // d{63--0}-->x 128 break; 129 } 130 default: ShouldNotReachHere(); 131 } 132 133 // Using acquire: Order JVMTI check and load of result wrt. succeeding check 134 // (LoadStore for volatile field). 135 __ membar(MacroAssembler::LoadLoad | MacroAssembler::LoadStore); 136 137 __ lw(t0, Address(rcounter_addr)); 138 __ bne(rcounter, t0, slow); 139 140 switch (type) { 141 case T_FLOAT: __ fmv_w_x(f10, result); break; 142 case T_DOUBLE: __ fmv_d_x(f10, result); break; 143 default: __ mv(x10, result); break; 144 } 145 __ ret(); 146 147 slowcase_entry_pclist[count++] = __ pc(); 148 __ bind(slow); 149 address slow_case_addr; 150 switch (type) { 151 case T_BOOLEAN: slow_case_addr = jni_GetBooleanField_addr(); break; 152 case T_BYTE: slow_case_addr = jni_GetByteField_addr(); break; 153 case T_CHAR: slow_case_addr = jni_GetCharField_addr(); break; 154 case T_SHORT: slow_case_addr = jni_GetShortField_addr(); break; 155 case T_INT: slow_case_addr = jni_GetIntField_addr(); break; 156 case T_LONG: slow_case_addr = jni_GetLongField_addr(); break; 157 case T_FLOAT: slow_case_addr = jni_GetFloatField_addr(); break; 158 case T_DOUBLE: slow_case_addr = jni_GetDoubleField_addr(); break; 159 default: ShouldNotReachHere(); 160 slow_case_addr = nullptr; // unreachable 161 } 162 163 { 164 __ enter(); 165 __ rt_call(slow_case_addr); 166 __ leave(); 167 __ ret(); 168 } 169 __ flush(); 170 171 return fast_entry; 172 } 173 174 175 address JNI_FastGetField::generate_fast_get_boolean_field() { 176 return generate_fast_get_int_field0(T_BOOLEAN); 177 } 178 179 address JNI_FastGetField::generate_fast_get_byte_field() { 180 return generate_fast_get_int_field0(T_BYTE); 181 } 182 183 address JNI_FastGetField::generate_fast_get_char_field() { 184 return generate_fast_get_int_field0(T_CHAR); 185 } 186 187 address JNI_FastGetField::generate_fast_get_short_field() { 188 return generate_fast_get_int_field0(T_SHORT); 189 } 190 191 address JNI_FastGetField::generate_fast_get_int_field() { 192 return generate_fast_get_int_field0(T_INT); 193 } 194 195 address JNI_FastGetField::generate_fast_get_long_field() { 196 return generate_fast_get_int_field0(T_LONG); 197 } 198 199 address JNI_FastGetField::generate_fast_get_float_field() { 200 return generate_fast_get_int_field0(T_FLOAT); 201 } 202 203 address JNI_FastGetField::generate_fast_get_double_field() { 204 return generate_fast_get_int_field0(T_DOUBLE); 205 } --- EOF ---