Mon, 26 Sep 2011 10:24:05 -0700
7081933: Use zeroing elimination optimization for large array
Summary: Don't zero new typeArray during runtime call if the allocation is followed by arraycopy into it.
Reviewed-by: twisti
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.
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19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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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 typedef void (*_zero_Fn)(HeapWord* to, size_t count);
161 static void pd_fill_to_aligned_words(HeapWord* tohw, size_t count, juint value) {
162 assert(MinObjAlignmentInBytes >= BytesPerLong, "need alternate implementation");
164 if (value == 0 && UseBlockZeroing &&
165 (count > (BlockZeroingLowLimit >> LogHeapWordSize))) {
166 // Call it only when block zeroing is used
167 ((_zero_Fn)StubRoutines::zero_aligned_words())(tohw, count);
168 } else {
169 julong* to = (julong*)tohw;
170 julong v = ((julong)value << 32) | value;
171 // If count is odd, odd will be equal to 1 on 32-bit platform
172 // and be equal to 0 on 64-bit platform.
173 size_t odd = count % (BytesPerLong / HeapWordSize) ;
175 size_t aligned_count = align_object_offset(count - odd) / HeapWordsPerLong;
176 julong* end = ((julong*)tohw) + aligned_count - 1;
177 while (to <= end) {
178 DEBUG_ONLY(count -= BytesPerLong / HeapWordSize ;)
179 *to++ = v;
180 }
181 assert(count == odd, "bad bounds on loop filling to aligned words");
182 if (odd) {
183 *((juint*)to) = value;
185 }
186 }
187 }
189 static void pd_fill_to_bytes(void* to, size_t count, jubyte value) {
190 (void)memset(to, value, count);
191 }
193 static void pd_zero_to_words(HeapWord* tohw, size_t count) {
194 pd_fill_to_words(tohw, count, 0);
195 }
197 static void pd_zero_to_bytes(void* to, size_t count) {
198 (void)memset(to, 0, count);
199 }
201 #endif // CPU_SPARC_VM_COPY_SPARC_HPP