1 /*
2 * Copyright (c) 2004, 2017, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2014, Red Hat Inc. All rights reserved.
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 *
24 */
25
26 #include "precompiled.hpp"
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 "runtime/safepoint.hpp"
34
35 #define __ masm->
36
37 #define BUFFER_SIZE 30*wordSize
38
39 // Instead of issuing a LoadLoad barrier we create an address
40 // dependency between loads; this might be more efficient.
41
42 // Common register usage:
43 // r0/v0: result
44 // c_rarg0: jni env
45 // c_rarg1: obj
46 // c_rarg2: jfield id
47
48 static const Register robj = r3;
49 static const Register rcounter = r4;
50 static const Register roffset = r5;
51 static const Register rcounter_addr = r6;
52 static const Register result = r7;
53
54 address JNI_FastGetField::generate_fast_get_int_field0(BasicType type) {
55 const char *name;
56 switch (type) {
57 case T_BOOLEAN: name = "jni_fast_GetBooleanField"; break;
58 case T_BYTE: name = "jni_fast_GetByteField"; break;
59 case T_CHAR: name = "jni_fast_GetCharField"; break;
60 case T_SHORT: name = "jni_fast_GetShortField"; break;
61 case T_INT: name = "jni_fast_GetIntField"; break;
62 case T_LONG: name = "jni_fast_GetLongField"; break;
63 case T_FLOAT: name = "jni_fast_GetFloatField"; break;
64 case T_DOUBLE: name = "jni_fast_GetDoubleField"; break;
65 default: ShouldNotReachHere();
66 name = NULL; // unreachable
67 }
68 ResourceMark rm;
69 BufferBlob* blob = BufferBlob::create(name, BUFFER_SIZE);
70 CodeBuffer cbuf(blob);
71 MacroAssembler* masm = new MacroAssembler(&cbuf);
72 address fast_entry = __ pc();
73
74 Label slow;
75
76 unsigned long offset;
77 __ adrp(rcounter_addr,
78 SafepointSynchronize::safepoint_counter_addr(), offset);
79 Address safepoint_counter_addr(rcounter_addr, offset);
80 __ ldrw(rcounter, safepoint_counter_addr);
81 __ tbnz(rcounter, 0, slow);
82 __ eor(robj, c_rarg1, rcounter);
83 __ eor(robj, robj, rcounter); // obj, since
84 // robj ^ rcounter ^ rcounter == robj
85 // robj is address dependent on rcounter.
86
87 BarrierSetAssembler* bs = BarrierSet::barrier_set()->barrier_set_assembler();
88 bs->try_resolve_jobject_in_native(masm, c_rarg0, robj, rscratch1, slow);
89
90 __ lsr(roffset, c_rarg2, 2); // offset
91
92 assert(count < LIST_CAPACITY, "LIST_CAPACITY too small");
93 speculative_load_pclist[count] = __ pc(); // Used by the segfault handler
94
95 // Ensure that field has finished loading before loading the safepoint_counter.
96 // We must not load into r0 yet. It's also c_rarg0 and would clobber the JNIEnv* pointer.
97 switch (type) {
98 case T_FLOAT:
99 case T_DOUBLE:
100 __ access_load_at(type, IN_HEAP, noreg /* tos: r0/v0 */, Address(robj, roffset), noreg, noreg);
101 __ membar(MacroAssembler::LoadLoad);
102 break;
103 default:
104 __ access_load_at(type, IN_HEAP, result, Address(robj, roffset), noreg, noreg);
105 // counter_addr is address dependent on result.
106 __ eor(rcounter_addr, rcounter_addr, result);
107 __ eor(rcounter_addr, rcounter_addr, result);
108 }
109
110 __ ldrw(rscratch1, safepoint_counter_addr);
111 __ cmpw(rcounter, rscratch1);
112 __ br (Assembler::NE, slow);
113
114 switch (type) {
115 case T_FLOAT:
116 case T_DOUBLE:
117 // Result is already in v0. Nothing to do.
118 break;
119 default:
120 // Move result over to r0.
121 __ mov(r0, result);
122 }
123 __ ret(lr);
124
125 slowcase_entry_pclist[count++] = __ pc();
126 __ bind(slow);
127 address slow_case_addr;
128 switch (type) {
129 case T_BOOLEAN: slow_case_addr = jni_GetBooleanField_addr(); break;
130 case T_BYTE: slow_case_addr = jni_GetByteField_addr(); break;
131 case T_CHAR: slow_case_addr = jni_GetCharField_addr(); break;
132 case T_SHORT: slow_case_addr = jni_GetShortField_addr(); break;
133 case T_INT: slow_case_addr = jni_GetIntField_addr(); break;
134 case T_LONG: slow_case_addr = jni_GetLongField_addr(); break;
135 case T_FLOAT: slow_case_addr = jni_GetFloatField_addr(); break;
136 case T_DOUBLE: slow_case_addr = jni_GetDoubleField_addr(); break;
137 default: ShouldNotReachHere();
138 slow_case_addr = NULL; // unreachable
139 }
140
141 {
142 __ enter();
143 __ lea(rscratch1, ExternalAddress(slow_case_addr));
144 __ blr(rscratch1);
145 __ maybe_isb();
146 __ leave();
147 __ ret(lr);
148 }
149 __ flush ();
150
151 return fast_entry;
152 }
153
154 address JNI_FastGetField::generate_fast_get_boolean_field() {
155 return generate_fast_get_int_field0(T_BOOLEAN);
156 }
157
158 address JNI_FastGetField::generate_fast_get_byte_field() {
159 return generate_fast_get_int_field0(T_BYTE);
160 }
161
162 address JNI_FastGetField::generate_fast_get_char_field() {
163 return generate_fast_get_int_field0(T_CHAR);
164 }
165
166 address JNI_FastGetField::generate_fast_get_short_field() {
167 return generate_fast_get_int_field0(T_SHORT);
168 }
169
170 address JNI_FastGetField::generate_fast_get_int_field() {
171 return generate_fast_get_int_field0(T_INT);
172 }
173
174 address JNI_FastGetField::generate_fast_get_long_field() {
175 return generate_fast_get_int_field0(T_LONG);
176 }
177
178 address JNI_FastGetField::generate_fast_get_float_field() {
179 return generate_fast_get_int_field0(T_FLOAT);
180 }
181
182 address JNI_FastGetField::generate_fast_get_double_field() {
183 return generate_fast_get_int_field0(T_DOUBLE);
184 }