icBuffer_aarch64.cpp revision 8413:92457dfb91bd 
1/*
2 * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2014, Red Hat Inc. All rights reserved.
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
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24 */
25
26#include "precompiled.hpp"
27#include "asm/macroAssembler.hpp"
28#include "asm/macroAssembler.inline.hpp"
29#include "code/icBuffer.hpp"
30#include "gc/shared/collectedHeap.inline.hpp"
31#include "interpreter/bytecodes.hpp"
32#include "memory/resourceArea.hpp"
33#include "nativeInst_aarch64.hpp"
34#include "oops/oop.inline.hpp"
35
36int InlineCacheBuffer::ic_stub_code_size() {
37  return (MacroAssembler::far_branches() ? 6 : 4) * NativeInstruction::instruction_size;
38}
39
40#define __ masm->
41
42void InlineCacheBuffer::assemble_ic_buffer_code(address code_begin, void* cached_value, address entry_point) {
43  ResourceMark rm;
44  CodeBuffer      code(code_begin, ic_stub_code_size());
45  MacroAssembler* masm            = new MacroAssembler(&code);
46  // note: even though the code contains an embedded value, we do not need reloc info
47  // because
48  // (1) the value is old (i.e., doesn't matter for scavenges)
49  // (2) these ICStubs are removed *before* a GC happens, so the roots disappear
50  // assert(cached_value == NULL || cached_oop->is_perm(), "must be perm oop");
51
52  address start = __ pc();
53  Label l;
54  __ ldr(rscratch2, l);
55  __ far_jump(ExternalAddress(entry_point));
56  __ align(wordSize);
57  __ bind(l);
58  __ emit_int64((int64_t)cached_value);
59  // Only need to invalidate the 1st two instructions - not the whole ic stub
60  ICache::invalidate_range(code_begin, InlineCacheBuffer::ic_stub_code_size());
61  assert(__ pc() - start == ic_stub_code_size(), "must be");
62}
63
64address InlineCacheBuffer::ic_buffer_entry_point(address code_begin) {
65  NativeMovConstReg* move = nativeMovConstReg_at(code_begin);   // creation also verifies the object
66  NativeJump* jump = nativeJump_at(code_begin + 4);
67  return jump->jump_destination();
68}
69
70
71void* InlineCacheBuffer::ic_buffer_cached_value(address code_begin) {
72  // The word containing the cached value is at the end of this IC buffer
73  uintptr_t *p = (uintptr_t *)(code_begin + ic_stub_code_size() - wordSize);
74  void* o = (void*)*p;
75  return o;
76}
77