1 /*
2 * Copyright (c) 2004, 2017, 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/macroAssembler.hpp"
27 #include "memory/resourceArea.hpp"
28 #include "prims/jniFastGetField.hpp"
29 #include "prims/jvm_misc.hpp"
30 #include "runtime/safepoint.hpp"
31
32 #define __ masm->
33
34 #define BUFFER_SIZE 30*wordSize
35
36 // Instead of issuing lfence for LoadLoad barrier, we create data dependency
37 // between loads, which is more efficient than lfence.
38
39 // Common register usage:
40 // rax/xmm0: result
41 // c_rarg0: jni env
42 // c_rarg1: obj
43 // c_rarg2: jfield id
44
45 static const Register robj = r9;
46 static const Register rcounter = r10;
47 static const Register roffset = r11;
48 static const Register rcounter_addr = r11;
49
50 // Warning: do not use rip relative addressing after the first counter load
51 // since that may scratch r10!
52
53 address JNI_FastGetField::generate_fast_get_int_field0(BasicType type) {
54 const char *name = NULL;
55 switch (type) {
56 case T_BOOLEAN: name = "jni_fast_GetBooleanField"; break;
57 case T_BYTE: name = "jni_fast_GetByteField"; break;
58 case T_CHAR: name = "jni_fast_GetCharField"; break;
59 case T_SHORT: name = "jni_fast_GetShortField"; break;
60 case T_INT: name = "jni_fast_GetIntField"; break;
61 case T_LONG: name = "jni_fast_GetLongField"; break;
62 default: ShouldNotReachHere();
63 }
64 ResourceMark rm;
65 BufferBlob* blob = BufferBlob::create(name, BUFFER_SIZE);
66 CodeBuffer cbuf(blob);
67 MacroAssembler* masm = new MacroAssembler(&cbuf);
68 address fast_entry = __ pc();
69
70 Label slow;
71
72 ExternalAddress counter(SafepointSynchronize::safepoint_counter_addr());
73 __ mov32 (rcounter, counter);
74 __ mov (robj, c_rarg1);
75 __ testb (rcounter, 1);
76 __ jcc (Assembler::notZero, slow);
77 if (os::is_MP()) {
78 __ xorptr(robj, rcounter);
79 __ xorptr(robj, rcounter); // obj, since
80 // robj ^ rcounter ^ rcounter == robj
81 // robj is data dependent on rcounter.
82 }
83
84 __ clear_jweak_tag(robj);
85
86 __ movptr(robj, Address(robj, 0)); // *obj
87 __ resolve_for_read(0, robj);
88 __ mov (roffset, c_rarg2);
89 __ shrptr(roffset, 2); // offset
90
91 assert(count < LIST_CAPACITY, "LIST_CAPACITY too small");
92 speculative_load_pclist[count] = __ pc();
93 switch (type) {
94 case T_BOOLEAN: __ movzbl (rax, Address(robj, roffset, Address::times_1)); break;
95 case T_BYTE: __ movsbl (rax, Address(robj, roffset, Address::times_1)); break;
96 case T_CHAR: __ movzwl (rax, Address(robj, roffset, Address::times_1)); break;
97 case T_SHORT: __ movswl (rax, Address(robj, roffset, Address::times_1)); break;
98 case T_INT: __ movl (rax, Address(robj, roffset, Address::times_1)); break;
99 case T_LONG: __ movq (rax, Address(robj, roffset, Address::times_1)); break;
100 default: ShouldNotReachHere();
101 }
102
103 if (os::is_MP()) {
104 __ lea(rcounter_addr, counter);
105 // ca is data dependent on rax.
106 __ xorptr(rcounter_addr, rax);
107 __ xorptr(rcounter_addr, rax);
108 __ cmpl (rcounter, Address(rcounter_addr, 0));
109 } else {
110 __ cmp32 (rcounter, counter);
111 }
112 __ jcc (Assembler::notEqual, slow);
113
114 __ ret (0);
115
116 slowcase_entry_pclist[count++] = __ pc();
117 __ bind (slow);
118 address slow_case_addr = NULL;
119 switch (type) {
120 case T_BOOLEAN: slow_case_addr = jni_GetBooleanField_addr(); break;
121 case T_BYTE: slow_case_addr = jni_GetByteField_addr(); break;
122 case T_CHAR: slow_case_addr = jni_GetCharField_addr(); break;
123 case T_SHORT: slow_case_addr = jni_GetShortField_addr(); break;
124 case T_INT: slow_case_addr = jni_GetIntField_addr(); break;
125 case T_LONG: slow_case_addr = jni_GetLongField_addr(); break;
126 default: break;
127 }
128 // tail call
129 __ jump (ExternalAddress(slow_case_addr));
130
131 __ flush ();
132
133 return fast_entry;
134 }
135
136 address JNI_FastGetField::generate_fast_get_boolean_field() {
137 return generate_fast_get_int_field0(T_BOOLEAN);
138 }
139
140 address JNI_FastGetField::generate_fast_get_byte_field() {
141 return generate_fast_get_int_field0(T_BYTE);
142 }
143
144 address JNI_FastGetField::generate_fast_get_char_field() {
145 return generate_fast_get_int_field0(T_CHAR);
146 }
147
148 address JNI_FastGetField::generate_fast_get_short_field() {
149 return generate_fast_get_int_field0(T_SHORT);
150 }
151
152 address JNI_FastGetField::generate_fast_get_int_field() {
153 return generate_fast_get_int_field0(T_INT);
154 }
155
156 address JNI_FastGetField::generate_fast_get_long_field() {
157 return generate_fast_get_int_field0(T_LONG);
158 }
159
160 address JNI_FastGetField::generate_fast_get_float_field0(BasicType type) {
161 const char *name = NULL;
162 switch (type) {
163 case T_FLOAT: name = "jni_fast_GetFloatField"; break;
164 case T_DOUBLE: name = "jni_fast_GetDoubleField"; break;
165 default: ShouldNotReachHere();
166 }
167 ResourceMark rm;
168 BufferBlob* blob = BufferBlob::create(name, BUFFER_SIZE);
169 CodeBuffer cbuf(blob);
170 MacroAssembler* masm = new MacroAssembler(&cbuf);
171 address fast_entry = __ pc();
172
173 Label slow;
174
175 ExternalAddress counter(SafepointSynchronize::safepoint_counter_addr());
176 __ mov32 (rcounter, counter);
177 __ mov (robj, c_rarg1);
178 __ testb (rcounter, 1);
179 __ jcc (Assembler::notZero, slow);
180 if (os::is_MP()) {
181 __ xorptr(robj, rcounter);
182 __ xorptr(robj, rcounter); // obj, since
183 // robj ^ rcounter ^ rcounter == robj
184 // robj is data dependent on rcounter.
185 }
186
187 __ clear_jweak_tag(robj);
188
189 __ movptr(robj, Address(robj, 0)); // *obj
190 __ resolve_for_read(0, robj);
191 __ mov (roffset, c_rarg2);
192 __ shrptr(roffset, 2); // offset
193
194 assert(count < LIST_CAPACITY, "LIST_CAPACITY too small");
195 speculative_load_pclist[count] = __ pc();
196 switch (type) {
197 case T_FLOAT: __ movflt (xmm0, Address(robj, roffset, Address::times_1)); break;
198 case T_DOUBLE: __ movdbl (xmm0, Address(robj, roffset, Address::times_1)); break;
199 default: ShouldNotReachHere();
200 }
201
202 if (os::is_MP()) {
203 __ lea(rcounter_addr, counter);
204 __ movdq (rax, xmm0);
205 // counter address is data dependent on xmm0.
206 __ xorptr(rcounter_addr, rax);
207 __ xorptr(rcounter_addr, rax);
208 __ cmpl (rcounter, Address(rcounter_addr, 0));
209 } else {
210 __ cmp32 (rcounter, counter);
211 }
212 __ jcc (Assembler::notEqual, slow);
213
214 __ ret (0);
215
216 slowcase_entry_pclist[count++] = __ pc();
217 __ bind (slow);
218 address slow_case_addr = NULL;
219 switch (type) {
220 case T_FLOAT: slow_case_addr = jni_GetFloatField_addr(); break;
221 case T_DOUBLE: slow_case_addr = jni_GetDoubleField_addr(); break;
222 default: break;
223 }
224 // tail call
225 __ jump (ExternalAddress(slow_case_addr));
226
227 __ flush ();
228
229 return fast_entry;
230 }
231
232 address JNI_FastGetField::generate_fast_get_float_field() {
233 return generate_fast_get_float_field0(T_FLOAT);
234 }
235
236 address JNI_FastGetField::generate_fast_get_double_field() {
237 return generate_fast_get_float_field0(T_DOUBLE);
238 }