icBuffer_x86.cpp revision 3602:da91efe96a93 
1/*
2 * Copyright (c) 1997, 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.
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23 */
24
25#include "precompiled.hpp"
26#include "asm/assembler.hpp"
27#include "assembler_x86.inline.hpp"
28#include "code/icBuffer.hpp"
29#include "gc_interface/collectedHeap.inline.hpp"
30#include "interpreter/bytecodes.hpp"
31#include "memory/resourceArea.hpp"
32#include "nativeInst_x86.hpp"
33#include "oops/oop.inline.hpp"
34#include "oops/oop.inline2.hpp"
35
36int InlineCacheBuffer::ic_stub_code_size() {
37  return NativeMovConstReg::instruction_size +
38         NativeJump::instruction_size +
39         1;
40  // so that code_end can be set in CodeBuffer
41  // 64bit 16 = 5 + 10 bytes + 1 byte
42  // 32bit 11 = 10 bytes + 1 byte
43}
44
45
46
47void InlineCacheBuffer::assemble_ic_buffer_code(address code_begin, void* cached_value, address entry_point) {
48  ResourceMark rm;
49  CodeBuffer      code(code_begin, ic_stub_code_size());
50  MacroAssembler* masm            = new MacroAssembler(&code);
51  // note: even though the code contains an embedded value, we do not need reloc info
52  // because
53  // (1) the value is old (i.e., doesn't matter for scavenges)
54  // (2) these ICStubs are removed *before* a GC happens, so the roots disappear
55  // assert(cached_value == NULL || cached_oop->is_perm(), "must be perm oop");
56  masm->lea(rax, AddressLiteral((address) cached_value, relocInfo::metadata_type));
57  masm->jump(ExternalAddress(entry_point));
58}
59
60
61address InlineCacheBuffer::ic_buffer_entry_point(address code_begin) {
62  NativeMovConstReg* move = nativeMovConstReg_at(code_begin);   // creation also verifies the object
63  NativeJump*        jump = nativeJump_at(move->next_instruction_address());
64  return jump->jump_destination();
65}
66
67
68void* InlineCacheBuffer::ic_buffer_cached_value(address code_begin) {
69  // creation also verifies the object
70  NativeMovConstReg* move = nativeMovConstReg_at(code_begin);
71  // Verifies the jump
72  NativeJump*        jump = nativeJump_at(move->next_instruction_address());
73  void* o = (void*)move->data();
74  return o;
75}
76