jdk8-mips64-public/hotspot: src/cpu/mips/vm/metaspaceShared_mips

     1 /*

     2  * Copyright (c) 2004, 2012, Oracle and/or its affiliates. All rights reserved.

     3  * Copyright (c) 2015, 2016, Loongson Technology. 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

    22  * questions.

    23  *

    24  */

    26 #include "precompiled.hpp"

    27 #include "asm/macroAssembler.hpp"

    28 #include "asm/codeBuffer.hpp"

    29 #include "memory/metaspaceShared.hpp"

    31 // Generate the self-patching vtable method:

    32 //

    33 // This method will be called (as any other Klass virtual method) with

    34 // the Klass itself as the first argument.  Example:

    35 //

    36 //      oop obj;

    37 //      int size = obj->klass()->klass_part()->oop_size(this);

    38 //

    39 // for which the virtual method call is Klass::oop_size();

    40 //

    41 // The dummy method is called with the Klass object as the first

    42 // operand, and an object as the second argument.

    43 //

    45 //=====================================================================

    47 // All of the dummy methods in the vtable are essentially identical,

    48 // differing only by an ordinal constant, and they bear no releationship

    49 // to the original method which the caller intended. Also, there needs

    50 // to be 'vtbl_list_size' instances of the vtable in order to

    51 // differentiate between the 'vtable_list_size' original Klass objects.

    53 #define __ masm->

    55 void MetaspaceShared::generate_vtable_methods(void** vtbl_list,

    56                                                    void** vtable,

    57                                                    char** md_top,

    58                                                    char* md_end,

    59                                                    char** mc_top,

    60                                                    char* mc_end) {

    62   intptr_t vtable_bytes = (num_virtuals * vtbl_list_size) * sizeof(void*);

    63   *(intptr_t *)(*md_top) = vtable_bytes;

    64   *md_top += sizeof(intptr_t);

    65   void** dummy_vtable = (void**)*md_top;

    66   *vtable = dummy_vtable;

    67   *md_top += vtable_bytes;

    69   // Get ready to generate dummy methods.

    71   CodeBuffer cb((unsigned char*)*mc_top, mc_end - *mc_top);

    72   MacroAssembler* masm = new MacroAssembler(&cb);

    74   Label common_code;

    75   for (int i = 0; i < vtbl_list_size; ++i) {

    76     for (int j = 0; j < num_virtuals; ++j) {

    77       dummy_vtable[num_virtuals * i + j] = (void*)masm->pc();

    79       // Load eax with a value indicating vtable/offset pair.

    80       // -- bits[ 7..0]  (8 bits) which virtual method in table?

    81       // -- bits[12..8]  (5 bits) which virtual method table?

    82       // -- must fit in 13-bit instruction immediate field.

    83       __ move(V0, (i << 8) + j);

    84       __ b(common_code);

    85       __ delayed()->nop();

    86     }

    87   }

    89   __ bind(common_code);

    91   __ srl(T9, V0, 8);		// isolate vtable identifier.

    92   __ shl(T9, LogBytesPerWord);

    93   __ li(AT, (long)vtbl_list);

    94   __ add(T9, AT, T9);

    95   __ lw(T9, T9, 0); 		// get correct vtable address.

    96   __ sw(T9, A0, 0);		// update vtable pointer.

    98   __ andi(V0, V0, 0x00ff);	// isolate vtable method index

    99   __ shl(V0, LogBytesPerWord);

   100   __ add(T9, T9, V0);		// address of real method pointer.

   101   __ jr(T9);			// get real method pointer.

   102   __ delayed()->nop();

   104   __ flush();

   106   *mc_top = (char*)__ pc();

   107 }

src/cpu/mips/vm/metaspaceShared_mips_64.cpp@d885f8d65c58