| /* |
| * Copyright (c) 2016, 2017, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| * |
| */ |
| |
| #include "precompiled.hpp" |
| #include "asm/macroAssembler.hpp" |
| #include "runtime/sharedRuntime.hpp" |
| #include "vmreg_x86.inline.hpp" |
| #ifdef COMPILER1 |
| #include "c1/c1_Runtime1.hpp" |
| #endif //COMPILER1 |
| |
| #define __ masm-> |
| |
| #ifdef COMPILER1 |
| // --------------------------------------------------------------------------- |
| // Object.hashCode, System.identityHashCode can pull the hashCode from the |
| // header word instead of doing a full VM transition once it's been computed. |
| // Since hashCode is usually polymorphic at call sites we can't do this |
| // optimization at the call site without a lot of work. |
| void SharedRuntime::inline_check_hashcode_from_object_header(MacroAssembler* masm, |
| const methodHandle& method, |
| Register obj_reg, |
| Register result) { |
| Label slowCase; |
| |
| // Unlike for Object.hashCode, System.identityHashCode is static method and |
| // gets object as argument instead of the receiver. |
| if (method->intrinsic_id() == vmIntrinsics::_identityHashCode) { |
| Label Continue; |
| // return 0 for null reference input |
| __ cmpptr(obj_reg, (int32_t)NULL_WORD); |
| __ jcc(Assembler::notEqual, Continue); |
| __ xorptr(result, result); |
| __ ret(0); |
| __ bind(Continue); |
| } |
| |
| __ movptr(result, Address(obj_reg, oopDesc::mark_offset_in_bytes())); |
| |
| // check if locked |
| __ testptr(result, markOop::unlocked_value); |
| __ jcc(Assembler::zero, slowCase); |
| |
| if (UseBiasedLocking) { |
| // Check if biased and fall through to runtime if so |
| __ testptr(result, markOop::biased_lock_bit_in_place); |
| __ jcc(Assembler::notZero, slowCase); |
| } |
| |
| // get hash |
| #ifdef _LP64 |
| // Read the header and build a mask to get its hash field. |
| // Depend on hash_mask being at most 32 bits and avoid the use of hash_mask_in_place |
| // because it could be larger than 32 bits in a 64-bit vm. See markOop.hpp. |
| __ shrptr(result, markOop::hash_shift); |
| __ andptr(result, markOop::hash_mask); |
| #else |
| __ andptr(result, markOop::hash_mask_in_place); |
| #endif //_LP64 |
| |
| // test if hashCode exists |
| __ jcc(Assembler::zero, slowCase); |
| #ifndef _LP64 |
| __ shrptr(result, markOop::hash_shift); |
| #endif |
| __ ret(0); |
| __ bind(slowCase); |
| } |
| #endif //COMPILER1 |
| |
