1 /*
2 * Copyright (c) 2008, 2020, 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.inline.hpp"
27 #include "asm/macroAssembler.hpp"
28 #include "code/codeBlob.hpp"
29 #include "memory/resourceArea.hpp"
30 #include "prims/jniFastGetField.hpp"
31 #include "prims/jvm_misc.hpp"
32 #include "prims/jvmtiExport.hpp"
33 #include "runtime/jniHandles.hpp"
34 #include "runtime/safepoint.hpp"
35
36 #define __ masm->
37
38 #define BUFFER_SIZE 120
39
generate_fast_get_int_field0(BasicType type)40 address JNI_FastGetField::generate_fast_get_int_field0(BasicType type) {
41 const char* name = NULL;
42 address slow_case_addr = NULL;
43 switch (type) {
44 case T_BOOLEAN:
45 name = "jni_fast_GetBooleanField";
46 slow_case_addr = jni_GetBooleanField_addr();
47 break;
48 case T_BYTE:
49 name = "jni_fast_GetByteField";
50 slow_case_addr = jni_GetByteField_addr();
51 break;
52 case T_CHAR:
53 name = "jni_fast_GetCharField";
54 slow_case_addr = jni_GetCharField_addr();
55 break;
56 case T_SHORT:
57 name = "jni_fast_GetShortField";
58 slow_case_addr = jni_GetShortField_addr();
59 break;
60 case T_INT:
61 name = "jni_fast_GetIntField";
62 slow_case_addr = jni_GetIntField_addr();
63 break;
64 case T_LONG:
65 name = "jni_fast_GetLongField";
66 slow_case_addr = jni_GetLongField_addr();
67 break;
68 case T_FLOAT:
69 name = "jni_fast_GetFloatField";
70 slow_case_addr = jni_GetFloatField_addr();
71 break;
72 case T_DOUBLE:
73 name = "jni_fast_GetDoubleField";
74 slow_case_addr = jni_GetDoubleField_addr();
75 break;
76 default:
77 ShouldNotReachHere();
78 }
79
80 // R0 - jni env
81 // R1 - object handle
82 // R2 - jfieldID
83
84 const Register Rsafepoint_counter_addr = R3;
85 const Register Robj = R1;
86 const Register Rres = R0;
87 const Register Rres_hi = R1;
88 const Register Rsafept_cnt = Rtemp;
89 const Register Rsafept_cnt2 = Rsafepoint_counter_addr;
90 const Register Rtmp1 = R3; // same as Rsafepoint_counter_addr
91 const Register Rtmp2 = R2; // same as jfieldID
92
93 assert_different_registers(Rsafepoint_counter_addr, Rsafept_cnt, Robj, Rres, LR);
94 assert_different_registers(Rsafept_cnt, R1, R2, Rtmp1, LR);
95 assert_different_registers(Rsafepoint_counter_addr, Rsafept_cnt, Rres, Rres_hi, Rtmp2, LR);
96 assert_different_registers(Rsafept_cnt2, Rsafept_cnt, Rres, Rres_hi, LR);
97
98 address fast_entry;
99
100 ResourceMark rm;
101 BufferBlob* blob = BufferBlob::create(name, BUFFER_SIZE);
102 CodeBuffer cbuf(blob);
103 MacroAssembler* masm = new MacroAssembler(&cbuf);
104 fast_entry = __ pc();
105 Label slow_case;
106
107 // Safepoint check
108 InlinedAddress safepoint_counter_addr(SafepointSynchronize::safepoint_counter_addr());
109 __ ldr_literal(Rsafepoint_counter_addr, safepoint_counter_addr);
110
111 __ push(RegisterSet(R0, R3)); // save incoming arguments for slow case
112
113 __ ldr_s32(Rsafept_cnt, Address(Rsafepoint_counter_addr));
114 __ tbnz(Rsafept_cnt, 0, slow_case);
115
116 __ bic(R1, R1, JNIHandles::weak_tag_mask);
117
118 if (JvmtiExport::can_post_field_access()) {
119 // Using barrier to order wrt. JVMTI check and load of result.
120 __ membar(MacroAssembler::Membar_mask_bits(MacroAssembler::LoadLoad), Rtmp1);
121
122 // Check to see if a field access watch has been set before we
123 // take the fast path.
124 __ ldr_global_s32(Rtmp1, (address)JvmtiExport::get_field_access_count_addr());
125 __ cbnz(Rtmp1, slow_case);
126
127 __ ldr(Robj, Address(R1));
128 } else {
129 // Address dependency restricts memory access ordering. It's cheaper than explicit LoadLoad barrier
130 __ andr(Rtmp1, Rsafept_cnt, (unsigned)1);
131 __ ldr(Robj, Address(R1, Rtmp1));
132 }
133
134 Address field_addr;
135 if (type != T_BOOLEAN
136 && type != T_INT
137 #ifndef __ABI_HARD__
138 && type != T_FLOAT
139 #endif // !__ABI_HARD__
140 ) {
141 // Only ldr and ldrb support embedded shift, other loads do not
142 __ add(Robj, Robj, AsmOperand(R2, lsr, 2));
143 field_addr = Address(Robj);
144 } else {
145 field_addr = Address(Robj, R2, lsr, 2);
146 }
147 assert(count < LIST_CAPACITY, "LIST_CAPACITY too small");
148 speculative_load_pclist[count] = __ pc();
149
150 switch (type) {
151 case T_BOOLEAN:
152 __ ldrb(Rres, field_addr);
153 break;
154 case T_BYTE:
155 __ ldrsb(Rres, field_addr);
156 break;
157 case T_CHAR:
158 __ ldrh(Rres, field_addr);
159 break;
160 case T_SHORT:
161 __ ldrsh(Rres, field_addr);
162 break;
163 case T_INT:
164 #ifndef __ABI_HARD__
165 case T_FLOAT:
166 #endif
167 __ ldr_s32(Rres, field_addr);
168 break;
169 case T_LONG:
170 #ifndef __ABI_HARD__
171 case T_DOUBLE:
172 #endif
173 // Safe to use ldrd since long and double fields are 8-byte aligned
174 __ ldrd(Rres, field_addr);
175 break;
176 #ifdef __ABI_HARD__
177 case T_FLOAT:
178 __ ldr_float(S0, field_addr);
179 break;
180 case T_DOUBLE:
181 __ ldr_double(D0, field_addr);
182 break;
183 #endif // __ABI_HARD__
184 default:
185 ShouldNotReachHere();
186 }
187
188 __ ldr_literal(Rsafepoint_counter_addr, safepoint_counter_addr);
189 #ifdef __ABI_HARD__
190 if (type == T_FLOAT || type == T_DOUBLE) {
191 __ fmrrd(Rres, Rres_hi, D0);
192 }
193 #endif // __ABI_HARD__
194
195 // Order JVMTI check and load of result wrt. succeeding check
196 // (LoadStore for volatile field).
197 __ membar(MacroAssembler::Membar_mask_bits(MacroAssembler::LoadLoad | MacroAssembler::LoadStore), Rtmp2);
198
199 __ ldr_s32(Rsafept_cnt2, Address(Rsafepoint_counter_addr));
200 __ cmp(Rsafept_cnt2, Rsafept_cnt);
201 // discards saved R0 R1 R2 R3
202 __ add(SP, SP, 4 * wordSize, eq);
203 __ bx(LR, eq);
204
205 slowcase_entry_pclist[count++] = __ pc();
206
207 __ bind(slow_case);
208 __ pop(RegisterSet(R0, R3));
209 // thumb mode switch handled by MacroAssembler::jump if needed
210 __ jump(slow_case_addr, relocInfo::none, Rtemp);
211
212 __ bind_literal(safepoint_counter_addr);
213
214 __ flush();
215
216 guarantee((__ pc() - fast_entry) <= BUFFER_SIZE, "BUFFER_SIZE too small");
217
218 return fast_entry;
219 }
220
generate_fast_get_float_field0(BasicType type)221 address JNI_FastGetField::generate_fast_get_float_field0(BasicType type) {
222 ShouldNotReachHere();
223 return NULL;
224 }
225
generate_fast_get_boolean_field()226 address JNI_FastGetField::generate_fast_get_boolean_field() {
227 return generate_fast_get_int_field0(T_BOOLEAN);
228 }
229
generate_fast_get_byte_field()230 address JNI_FastGetField::generate_fast_get_byte_field() {
231 return generate_fast_get_int_field0(T_BYTE);
232 }
233
generate_fast_get_char_field()234 address JNI_FastGetField::generate_fast_get_char_field() {
235 return generate_fast_get_int_field0(T_CHAR);
236 }
237
generate_fast_get_short_field()238 address JNI_FastGetField::generate_fast_get_short_field() {
239 return generate_fast_get_int_field0(T_SHORT);
240 }
241
generate_fast_get_int_field()242 address JNI_FastGetField::generate_fast_get_int_field() {
243 return generate_fast_get_int_field0(T_INT);
244 }
245
generate_fast_get_long_field()246 address JNI_FastGetField::generate_fast_get_long_field() {
247 return generate_fast_get_int_field0(T_LONG);
248 }
249
generate_fast_get_float_field()250 address JNI_FastGetField::generate_fast_get_float_field() {
251 return generate_fast_get_int_field0(T_FLOAT);
252 }
253
generate_fast_get_double_field()254 address JNI_FastGetField::generate_fast_get_double_field() {
255 return generate_fast_get_int_field0(T_DOUBLE);
256 }
257