Mercurial > jdk8-mips64-public > hotspot / file revision
src/cpu/sparc/vm/copy_sparc.hpp@e1162778c1c8
src/cpu/sparc/vm/copy_sparc.hpp
Thu, 07 Apr 2011 09:53:20 -0700
- author
- johnc
- date
- Thu, 07 Apr 2011 09:53:20 -0700
- changeset 2781
- e1162778c1c8
- parent 2314
- f95d63e2154a
- child 3092
- baf763f388e6
- permissions
- -rw-r--r--
7009266: G1: assert(obj->is_oop_or_null(true )) failed: Error
Summary: A referent object that is only weakly reachable at the start of concurrent marking but is re-attached to the strongly reachable object graph during marking may not be marked as live. This can cause the reference object to be processed prematurely and leave dangling pointers to the referent object. Implement a read barrier for the java.lang.ref.Reference::referent field by intrinsifying the Reference.get() method, and intercepting accesses though JNI, reflection, and Unsafe, so that when a non-null referent object is read it is also logged in an SATB buffer.
Reviewed-by: kvn, iveresov, never, tonyp, dholmes
1 /*
2 * Copyright (c) 2003, 2010, 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 */
25 #ifndef CPU_SPARC_VM_COPY_SPARC_HPP
26 #define CPU_SPARC_VM_COPY_SPARC_HPP
28 // Inline functions for memory copy and fill.
30 static void pd_conjoint_words(HeapWord* from, HeapWord* to, size_t count) {
31 (void)memmove(to, from, count * HeapWordSize);
32 }
34 static void pd_disjoint_words(HeapWord* from, HeapWord* to, size_t count) {
35 switch (count) {
36 case 8: to[7] = from[7];
37 case 7: to[6] = from[6];
38 case 6: to[5] = from[5];
39 case 5: to[4] = from[4];
40 case 4: to[3] = from[3];
41 case 3: to[2] = from[2];
42 case 2: to[1] = from[1];
43 case 1: to[0] = from[0];
44 case 0: break;
45 default: (void)memcpy(to, from, count * HeapWordSize);
46 break;
47 }
48 }
50 static void pd_disjoint_words_atomic(HeapWord* from, HeapWord* to, size_t count) {
51 switch (count) {
52 case 8: to[7] = from[7];
53 case 7: to[6] = from[6];
54 case 6: to[5] = from[5];
55 case 5: to[4] = from[4];
56 case 4: to[3] = from[3];
57 case 3: to[2] = from[2];
58 case 2: to[1] = from[1];
59 case 1: to[0] = from[0];
60 case 0: break;
61 default: while (count-- > 0) {
62 *to++ = *from++;
63 }
64 break;
65 }
66 }
68 static void pd_aligned_conjoint_words(HeapWord* from, HeapWord* to, size_t count) {
69 (void)memmove(to, from, count * HeapWordSize);
70 }
72 static void pd_aligned_disjoint_words(HeapWord* from, HeapWord* to, size_t count) {
73 pd_disjoint_words(from, to, count);
74 }
76 static void pd_conjoint_bytes(void* from, void* to, size_t count) {
77 (void)memmove(to, from, count);
78 }
80 static void pd_conjoint_bytes_atomic(void* from, void* to, size_t count) {
81 (void)memmove(to, from, count);
82 }
84 static void pd_conjoint_jshorts_atomic(jshort* from, jshort* to, size_t count) {
85 // FIXME
86 (void)memmove(to, from, count << LogBytesPerShort);
87 }
89 static void pd_conjoint_jints_atomic(jint* from, jint* to, size_t count) {
90 // FIXME
91 (void)memmove(to, from, count << LogBytesPerInt);
92 }
94 static void pd_conjoint_jlongs_atomic(jlong* from, jlong* to, size_t count) {
95 #ifdef _LP64
96 assert(BytesPerLong == BytesPerOop, "jlongs and oops must be the same size");
97 pd_conjoint_oops_atomic((oop*)from, (oop*)to, count);
98 #else
99 // Guarantee use of ldd/std via some asm code, because compiler won't.
100 // See solaris_sparc.il.
101 _Copy_conjoint_jlongs_atomic(from, to, count);
102 #endif
103 }
105 static void pd_conjoint_oops_atomic(oop* from, oop* to, size_t count) {
106 // Do better than this: inline memmove body NEEDS CLEANUP
107 if (from > to) {
108 while (count-- > 0) {
109 // Copy forwards
110 *to++ = *from++;
111 }
112 } else {
113 from += count - 1;
114 to += count - 1;
115 while (count-- > 0) {
116 // Copy backwards
117 *to-- = *from--;
118 }
119 }
120 }
122 static void pd_arrayof_conjoint_bytes(HeapWord* from, HeapWord* to, size_t count) {
123 pd_conjoint_bytes_atomic(from, to, count);
124 }
126 static void pd_arrayof_conjoint_jshorts(HeapWord* from, HeapWord* to, size_t count) {
127 pd_conjoint_jshorts_atomic((jshort*)from, (jshort*)to, count);
128 }
130 static void pd_arrayof_conjoint_jints(HeapWord* from, HeapWord* to, size_t count) {
131 pd_conjoint_jints_atomic((jint*)from, (jint*)to, count);
132 }
134 static void pd_arrayof_conjoint_jlongs(HeapWord* from, HeapWord* to, size_t count) {
135 pd_conjoint_jlongs_atomic((jlong*)from, (jlong*)to, count);
136 }
138 static void pd_arrayof_conjoint_oops(HeapWord* from, HeapWord* to, size_t count) {
139 pd_conjoint_oops_atomic((oop*)from, (oop*)to, count);
140 }
142 static void pd_fill_to_words(HeapWord* tohw, size_t count, juint value) {
143 #ifdef _LP64
144 guarantee(mask_bits((uintptr_t)tohw, right_n_bits(LogBytesPerLong)) == 0,
145 "unaligned fill words");
146 julong* to = (julong*)tohw;
147 julong v = ((julong)value << 32) | value;
148 while (count-- > 0) {
149 *to++ = v;
150 }
151 #else // _LP64
152 juint* to = (juint*)tohw;
153 while (count-- > 0) {
154 *to++ = value;
155 }
156 #endif // _LP64
157 }
159 static void pd_fill_to_aligned_words(HeapWord* tohw, size_t count, juint value) {
160 assert(MinObjAlignmentInBytes >= BytesPerLong, "need alternate implementation");
162 julong* to = (julong*)tohw;
163 julong v = ((julong)value << 32) | value;
164 // If count is odd, odd will be equal to 1 on 32-bit platform
165 // and be equal to 0 on 64-bit platform.
166 size_t odd = count % (BytesPerLong / HeapWordSize) ;
168 size_t aligned_count = align_object_offset(count - odd) / HeapWordsPerLong;
169 julong* end = ((julong*)tohw) + aligned_count - 1;
170 while (to <= end) {
171 DEBUG_ONLY(count -= BytesPerLong / HeapWordSize ;)
172 *to++ = v;
173 }
174 assert(count == odd, "bad bounds on loop filling to aligned words");
175 if (odd) {
176 *((juint*)to) = value;
178 }
179 }
181 static void pd_fill_to_bytes(void* to, size_t count, jubyte value) {
182 (void)memset(to, value, count);
183 }
185 static void pd_zero_to_words(HeapWord* tohw, size_t count) {
186 pd_fill_to_words(tohw, count, 0);
187 }
189 static void pd_zero_to_bytes(void* to, size_t count) {
190 (void)memset(to, 0, count);
191 }
193 #endif // CPU_SPARC_VM_COPY_SPARC_HPP
