truffle: src/share/vm/oops/arrayOop.hpp annotate

annotate src/share/vm/oops/arrayOop.hpp @ 452:00b023ae2d78

6722113: CMS: Incorrect overflow handling during precleaning of Reference lists Summary: When we encounter marking stack overflow during precleaning of Reference lists, we were using the overflow list mechanism, which can cause problems on account of mutating the mark word of the header because of conflicts with mutator accesses and updates of that field. Instead we should use the usual mechanism for overflow handling in concurrent phases, namely dirtying of the card on which the overflowed object lies. Since precleaning effectively does a form of discovered list processing, albeit with discovery enabled, we needed to adjust some code to be correct in the face of interleaved processing and discovery. Reviewed-by: apetrusenko, jcoomes

author	ysr
date	Thu, 20 Nov 2008 12:27:41 -0800
parents	d1605aabd0a1
children	7d7a7c599c17

rev	line source
0 a61af66fc99e Initial load duke parents: diff changeset	1 /*
196 d1605aabd0a1 6719955: Update copyright year xdono parents: 165 diff changeset	2 * Copyright 1997-2008 Sun Microsystems, Inc. All Rights Reserved.
0 a61af66fc99e Initial load duke parents: diff changeset	3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
a61af66fc99e Initial load duke parents: diff changeset	4 *
a61af66fc99e Initial load duke parents: diff changeset	5 * This code is free software; you can redistribute it and/or modify it
a61af66fc99e Initial load duke parents: diff changeset	6 * under the terms of the GNU General Public License version 2 only, as
a61af66fc99e Initial load duke parents: diff changeset	7 * published by the Free Software Foundation.
a61af66fc99e Initial load duke parents: diff changeset	8 *
a61af66fc99e Initial load duke parents: diff changeset	9 * This code is distributed in the hope that it will be useful, but WITHOUT
a61af66fc99e Initial load duke parents: diff changeset	10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
a61af66fc99e Initial load duke parents: diff changeset	11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
a61af66fc99e Initial load duke parents: diff changeset	12 * version 2 for more details (a copy is included in the LICENSE file that
a61af66fc99e Initial load duke parents: diff changeset	13 * accompanied this code).
a61af66fc99e Initial load duke parents: diff changeset	14 *
a61af66fc99e Initial load duke parents: diff changeset	15 * You should have received a copy of the GNU General Public License version
a61af66fc99e Initial load duke parents: diff changeset	16 * 2 along with this work; if not, write to the Free Software Foundation,
a61af66fc99e Initial load duke parents: diff changeset	17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
a61af66fc99e Initial load duke parents: diff changeset	18 *
a61af66fc99e Initial load duke parents: diff changeset	19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
a61af66fc99e Initial load duke parents: diff changeset	20 * CA 95054 USA or visit www.sun.com if you need additional information or
a61af66fc99e Initial load duke parents: diff changeset	21 * have any questions.
a61af66fc99e Initial load duke parents: diff changeset	22 *
a61af66fc99e Initial load duke parents: diff changeset	23 */
a61af66fc99e Initial load duke parents: diff changeset	24
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	25 // arrayOopDesc is the abstract baseclass for all arrays. It doesn't
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	26 // declare pure virtual to enforce this because that would allocate a vtbl
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	27 // in each instance, which we don't want.
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	28
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	29 // The layout of array Oops is:
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	30 //
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	31 // markOop
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	32 // klassOop // 32 bits if compressed but declared 64 in LP64.
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	33 // length // shares klass memory or allocated after declared fields.
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	34
0 a61af66fc99e Initial load duke parents: diff changeset	35
a61af66fc99e Initial load duke parents: diff changeset	36 class arrayOopDesc : public oopDesc {
a61af66fc99e Initial load duke parents: diff changeset	37 friend class VMStructs;
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	38
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	39 // Interpreter/Compiler offsets
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	40
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	41 // Header size computation.
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	42 // The header is considered the oop part of this type plus the length.
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	43 // Returns the aligned header_size_in_bytes. This is not equivalent to
165 437d03ea40b1 6703888: Compressed Oops: use the 32-bits gap after klass in a object kvn parents: 113 diff changeset	44 // sizeof(arrayOopDesc) which should not appear in the code.
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	45 static int header_size_in_bytes() {
165 437d03ea40b1 6703888: Compressed Oops: use the 32-bits gap after klass in a object kvn parents: 113 diff changeset	46 size_t hs = align_size_up(length_offset_in_bytes() + sizeof(int),
437d03ea40b1 6703888: Compressed Oops: use the 32-bits gap after klass in a object kvn parents: 113 diff changeset	47 HeapWordSize);
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	48 #ifdef ASSERT
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	49 // make sure it isn't called before UseCompressedOops is initialized.
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	50 static size_t arrayoopdesc_hs = 0;
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	51 if (arrayoopdesc_hs == 0) arrayoopdesc_hs = hs;
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	52 assert(arrayoopdesc_hs == hs, "header size can't change");
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	53 #endif // ASSERT
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	54 return (int)hs;
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	55 }
0 a61af66fc99e Initial load duke parents: diff changeset	56
a61af66fc99e Initial load duke parents: diff changeset	57 public:
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	58 // The _length field is not declared in C++. It is allocated after the
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	59 // declared nonstatic fields in arrayOopDesc if not compressed, otherwise
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	60 // it occupies the second half of the _klass field in oopDesc.
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	61 static int length_offset_in_bytes() {
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	62 return UseCompressedOops ? klass_gap_offset_in_bytes() :
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	63 sizeof(arrayOopDesc);
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	64 }
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	65
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	66 // Returns the offset of the first element.
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	67 static int base_offset_in_bytes(BasicType type) {
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	68 return header_size(type) * HeapWordSize;
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	69 }
0 a61af66fc99e Initial load duke parents: diff changeset	70
a61af66fc99e Initial load duke parents: diff changeset	71 // Returns the address of the first element.
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	72 void* base(BasicType type) const {
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	73 return (void*) (((intptr_t) this) + base_offset_in_bytes(type));
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	74 }
0 a61af66fc99e Initial load duke parents: diff changeset	75
a61af66fc99e Initial load duke parents: diff changeset	76 // Tells whether index is within bounds.
a61af66fc99e Initial load duke parents: diff changeset	77 bool is_within_bounds(int index) const { return 0 <= index && index < length(); }
a61af66fc99e Initial load duke parents: diff changeset	78
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	79 // Accessors for instance variable which is not a C++ declared nonstatic
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	80 // field.
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	81 int length() const {
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	82 return (int)(((intptr_t)this) + length_offset_in_bytes());
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	83 }
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	84 void set_length(int length) {
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	85 (int)(((intptr_t)this) + length_offset_in_bytes()) = length;
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	86 }
0 a61af66fc99e Initial load duke parents: diff changeset	87
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	88 // Should only be called with constants as argument
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	89 // (will not constant fold otherwise)
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	90 // Returns the header size in words aligned to the requirements of the
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	91 // array object type.
0 a61af66fc99e Initial load duke parents: diff changeset	92 static int header_size(BasicType type) {
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	93 size_t typesize_in_bytes = header_size_in_bytes();
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	94 return (int)(Universe::element_type_should_be_aligned(type)
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	95 ? align_object_size(typesize_in_bytes/HeapWordSize)
ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	96 : typesize_in_bytes/HeapWordSize);
0 a61af66fc99e Initial load duke parents: diff changeset	97 }
a61af66fc99e Initial load duke parents: diff changeset	98
a61af66fc99e Initial load duke parents: diff changeset	99 // This method returns the maximum length that can passed into
a61af66fc99e Initial load duke parents: diff changeset	100 // typeArrayOop::object_size(scale, length, header_size) without causing an
a61af66fc99e Initial load duke parents: diff changeset	101 // overflow. We substract an extra 2*wordSize to guard against double word
a61af66fc99e Initial load duke parents: diff changeset	102 // alignments. It gets the scale from the type2aelembytes array.
a61af66fc99e Initial load duke parents: diff changeset	103 static int32_t max_array_length(BasicType type) {
a61af66fc99e Initial load duke parents: diff changeset	104 assert(type >= 0 && type < T_CONFLICT, "wrong type");
29 d5fc211aea19 6633953: type2aelembytes{T_ADDRESS} should be 8 bytes in 64 bit VM kvn parents: 0 diff changeset	105 assert(type2aelembytes(type) != 0, "wrong type");
0 a61af66fc99e Initial load duke parents: diff changeset	106 // We use max_jint, since object_size is internally represented by an 'int'
a61af66fc99e Initial load duke parents: diff changeset	107 // This gives us an upper bound of max_jint words for the size of the oop.
a61af66fc99e Initial load duke parents: diff changeset	108 int32_t max_words = (max_jint - header_size(type) - 2);
113 ba764ed4b6f2 6420645: Create a vm that uses compressed oops for up to 32gb heapsizes coleenp parents: 29 diff changeset	109 int elembytes = type2aelembytes(type);
0 a61af66fc99e Initial load duke parents: diff changeset	110 jlong len = ((jlong)max_words * HeapWordSize) / elembytes;
a61af66fc99e Initial load duke parents: diff changeset	111 return (len > max_jint) ? max_jint : (int32_t)len;
a61af66fc99e Initial load duke parents: diff changeset	112 }
a61af66fc99e Initial load duke parents: diff changeset	113
a61af66fc99e Initial load duke parents: diff changeset	114 };

Mercurial > hg > truffle

annotate src/share/vm/oops/arrayOop.hpp @ 452:00b023ae2d78