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) 2002, 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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21 * questions.
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23 */
25 #ifndef CPU_SPARC_VM_JAVAFRAMEANCHOR_SPARC_HPP
26 #define CPU_SPARC_VM_JAVAFRAMEANCHOR_SPARC_HPP
28 private:
29 volatile int _flags;
31 public:
33 enum pd_Constants {
34 flushed = 1 // winodows have flushed
35 };
37 int flags(void) { return _flags; }
38 void set_flags(int flags) { _flags = flags; }
40 static ByteSize flags_offset() { return byte_offset_of(JavaFrameAnchor, _flags); }
42 // Each arch must define clear, copy
43 // These are used by objects that only care about:
44 // 1 - initializing a new state (thread creation, javaCalls)
45 // 2 - saving a current state (javaCalls)
46 // 3 - restoring an old state (javaCalls)
48 void clear(void) {
49 // clearing _last_Java_sp must be first
50 _last_Java_sp = NULL;
51 // fence?
52 _flags = 0;
53 _last_Java_pc = NULL;
54 }
56 void copy(JavaFrameAnchor* src) {
57 // In order to make sure the transition state is valid for "this"
58 // We must clear _last_Java_sp before copying the rest of the new data
59 //
60 // Hack Alert: Temporary bugfix for 4717480/4721647
61 // To act like previous version (pd_cache_state) don't NULL _last_Java_sp
62 // unless the value is changing
63 //
64 if (_last_Java_sp != src->_last_Java_sp)
65 _last_Java_sp = NULL;
67 _flags = src->_flags;
68 _last_Java_pc = src->_last_Java_pc;
69 // Must be last so profiler will always see valid frame if has_last_frame() is true
70 _last_Java_sp = src->_last_Java_sp;
71 }
73 // Is stack walkable
74 inline bool walkable( void) {
75 return _flags & flushed;
76 }
78 void make_walkable(JavaThread* thread);
80 void set_last_Java_sp(intptr_t* sp) { _last_Java_sp = sp; }
82 address last_Java_pc(void) { return _last_Java_pc; }
84 // These are only used by friends
85 private:
87 intptr_t* last_Java_sp() const {
88 // _last_Java_sp will always be a an unbiased stack pointer
89 // if is is biased then some setter screwed up. This is
90 // deadly.
91 #ifdef _LP64
92 assert(((intptr_t)_last_Java_sp & 0xF) == 0, "Biased last_Java_sp");
93 #endif
94 return _last_Java_sp;
95 }
97 void capture_last_Java_pc(intptr_t* sp);
99 void set_window_flushed( void) {
100 _flags |= flushed;
101 OrderAccess::fence();
102 }
104 #endif // CPU_SPARC_VM_JAVAFRAMEANCHOR_SPARC_HPP