comparison src/cpu/x86/vm/metaspaceShared_x86_64.cpp @ 6725:da91efe96a93

6964458: Reimplement class meta-data storage to use native memory Summary: Remove PermGen, allocate meta-data in metaspace linked to class loaders, rewrite GC walking, rewrite and rename metadata to be C++ classes Reviewed-by: jmasa, stefank, never, coleenp, kvn, brutisso, mgerdin, dholmes, jrose, twisti, roland Contributed-by: jmasa <jon.masamitsu@oracle.com>, stefank <stefan.karlsson@oracle.com>, mgerdin <mikael.gerdin@oracle.com>, never <tom.rodriguez@oracle.com>
author coleenp
date Sat, 01 Sep 2012 13:25:18 -0400
parents src/cpu/x86/vm/dump_x86_64.cpp@f95d63e2154a
children cd3d6a6b95d9
comparison
equal deleted inserted replaced
6724:36d1d483d5d6 6725:da91efe96a93
1 /*
2 * Copyright (c) 2004, 2012, 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 */
24
25 #include "precompiled.hpp"
26 #include "assembler_x86.inline.hpp"
27 #include "memory/metaspaceShared.hpp"
28
29 // Generate the self-patching vtable method:
30 //
31 // This method will be called (as any other Klass virtual method) with
32 // the Klass itself as the first argument. Example:
33 //
34 // oop obj;
35 // int size = obj->klass()->oop_size(this);
36 //
37 // for which the virtual method call is Klass::oop_size();
38 //
39 // The dummy method is called with the Klass object as the first
40 // operand, and an object as the second argument.
41 //
42
43 //=====================================================================
44
45 // All of the dummy methods in the vtable are essentially identical,
46 // differing only by an ordinal constant, and they bear no relationship
47 // to the original method which the caller intended. Also, there needs
48 // to be 'vtbl_list_size' instances of the vtable in order to
49 // differentiate between the 'vtable_list_size' original Klass objects.
50
51 #define __ masm->
52
53 void MetaspaceShared::generate_vtable_methods(void** vtbl_list,
54 void** vtable,
55 char** md_top,
56 char* md_end,
57 char** mc_top,
58 char* mc_end) {
59
60 intptr_t vtable_bytes = (num_virtuals * vtbl_list_size) * sizeof(void*);
61 *(intptr_t *)(*md_top) = vtable_bytes;
62 *md_top += sizeof(intptr_t);
63 void** dummy_vtable = (void**)*md_top;
64 *vtable = dummy_vtable;
65 *md_top += vtable_bytes;
66
67 // Get ready to generate dummy methods.
68
69 CodeBuffer cb((unsigned char*)*mc_top, mc_end - *mc_top);
70 MacroAssembler* masm = new MacroAssembler(&cb);
71
72 Label common_code;
73 for (int i = 0; i < vtbl_list_size; ++i) {
74 for (int j = 0; j < num_virtuals; ++j) {
75 dummy_vtable[num_virtuals * i + j] = (void*)masm->pc();
76
77 // Load eax with a value indicating vtable/offset pair.
78 // -- bits[ 7..0] (8 bits) which virtual method in table?
79 // -- bits[12..8] (5 bits) which virtual method table?
80 // -- must fit in 13-bit instruction immediate field.
81 __ movl(rax, (i << 8) + j);
82 __ jmp(common_code);
83 }
84 }
85
86 __ bind(common_code);
87
88 // Expecting to be called with "thiscall" convections -- the arguments
89 // are on the stack and the "this" pointer is in c_rarg0. In addition, rax
90 // was set (above) to the offset of the method in the table.
91
92 __ push(c_rarg1); // save & free register
93 __ push(c_rarg0); // save "this"
94 __ mov(c_rarg0, rax);
95 __ shrptr(c_rarg0, 8); // isolate vtable identifier.
96 __ shlptr(c_rarg0, LogBytesPerWord);
97 __ lea(c_rarg1, ExternalAddress((address)vtbl_list)); // ptr to correct vtable list.
98 __ addptr(c_rarg1, c_rarg0); // ptr to list entry.
99 __ movptr(c_rarg1, Address(c_rarg1, 0)); // get correct vtable address.
100 __ pop(c_rarg0); // restore "this"
101 __ movptr(Address(c_rarg0, 0), c_rarg1); // update vtable pointer.
102
103 __ andptr(rax, 0x00ff); // isolate vtable method index
104 __ shlptr(rax, LogBytesPerWord);
105 __ addptr(rax, c_rarg1); // address of real method pointer.
106 __ pop(c_rarg1); // restore register.
107 __ movptr(rax, Address(rax, 0)); // get real method pointer.
108 __ jmp(rax); // jump to the real method.
109
110 __ flush();
111
112 *mc_top = (char*)__ pc();
113 }