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 __ testb(robj, JNIHandles::weak_tag_mask);
85 __ jcc (Assembler::notZero, slow);
86
87 __ movptr(robj, Address(robj, 0)); // *obj
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();
126 }
127 // tail call
128 __ jump (ExternalAddress(slow_case_addr));
129
130 __ flush ();
131
132 return fast_entry;
133 }
134
135 address JNI_FastGetField::generate_fast_get_boolean_field() {
136 return generate_fast_get_int_field0(T_BOOLEAN);
137 }
138
139 address JNI_FastGetField::generate_fast_get_byte_field() {
140 return generate_fast_get_int_field0(T_BYTE);
141 }
142
143 address JNI_FastGetField::generate_fast_get_char_field() {
144 return generate_fast_get_int_field0(T_CHAR);
145 }
146
147 address JNI_FastGetField::generate_fast_get_short_field() {
148 return generate_fast_get_int_field0(T_SHORT);
149 }
150
151 address JNI_FastGetField::generate_fast_get_int_field() {
152 return generate_fast_get_int_field0(T_INT);
153 }
154
155 address JNI_FastGetField::generate_fast_get_long_field() {
156 return generate_fast_get_int_field0(T_LONG);
157 }
158
159 address JNI_FastGetField::generate_fast_get_float_field0(BasicType type) {
160 const char *name = NULL;
161 switch (type) {
162 case T_FLOAT: name = "jni_fast_GetFloatField"; break;
163 case T_DOUBLE: name = "jni_fast_GetDoubleField"; break;
164 default: ShouldNotReachHere();
165 }
166 ResourceMark rm;
167 BufferBlob* blob = BufferBlob::create(name, BUFFER_SIZE);
168 CodeBuffer cbuf(blob);
169 MacroAssembler* masm = new MacroAssembler(&cbuf);
170 address fast_entry = __ pc();
171
172 Label slow;
173
174 ExternalAddress counter(SafepointSynchronize::safepoint_counter_addr());
175 __ mov32 (rcounter, counter);
176 __ mov (robj, c_rarg1);
177 __ testb (rcounter, 1);
178 __ jcc (Assembler::notZero, slow);
179 if (os::is_MP()) {
180 __ xorptr(robj, rcounter);
181 __ xorptr(robj, rcounter); // obj, since
182 // robj ^ rcounter ^ rcounter == robj
183 // robj is data dependent on rcounter.
184 }
185
186 __ testb(robj, JNIHandles::weak_tag_mask);
187 __ jcc (Assembler::notZero, slow);
188
189 __ movptr(robj, Address(robj, 0)); // *obj
190 __ mov (roffset, c_rarg2);
191 __ shrptr(roffset, 2); // offset
192
193 assert(count < LIST_CAPACITY, "LIST_CAPACITY too small");
194 speculative_load_pclist[count] = __ pc();
195 switch (type) {
196 case T_FLOAT: __ movflt (xmm0, Address(robj, roffset, Address::times_1)); break;
197 case T_DOUBLE: __ movdbl (xmm0, Address(robj, roffset, Address::times_1)); break;
198 default: ShouldNotReachHere();
199 }
200
201 if (os::is_MP()) {
202 __ lea(rcounter_addr, counter);
203 __ movdq (rax, xmm0);
204 // counter address is data dependent on xmm0.
205 __ xorptr(rcounter_addr, rax);
206 __ xorptr(rcounter_addr, rax);
207 __ cmpl (rcounter, Address(rcounter_addr, 0));
208 } else {
209 __ cmp32 (rcounter, counter);
210 }
211 __ jcc (Assembler::notEqual, slow);
212
213 __ ret (0);
214
215 slowcase_entry_pclist[count++] = __ pc();
216 __ bind (slow);
217 address slow_case_addr = NULL;
218 switch (type) {
219 case T_FLOAT: slow_case_addr = jni_GetFloatField_addr(); break;
220 case T_DOUBLE: slow_case_addr = jni_GetDoubleField_addr();
221 }
222 // tail call
223 __ jump (ExternalAddress(slow_case_addr));
224
225 __ flush ();
226
227 return fast_entry;
228 }
229
230 address JNI_FastGetField::generate_fast_get_float_field() {
231 return generate_fast_get_float_field0(T_FLOAT);
232 }
233
234 address JNI_FastGetField::generate_fast_get_double_field() {
235 return generate_fast_get_float_field0(T_DOUBLE);
236 }