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. 22 * 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