1 /*

     2  * Copyright (c) 1999, 2007, Oracle and/or its affiliates. All rights reserved.

     3  * Copyright 2009 Red Hat, Inc.

     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  */

    25 

    26 class SharkCodeBuffer : public StackObj {

    27  public:

    28   SharkCodeBuffer(MacroAssembler* masm)

    29     : _masm(masm), _base_pc(NULL) {}

    30 

    31  private:

    32   MacroAssembler* _masm;

    33   llvm::Value*    _base_pc;

    34 

    35  private:

    36   MacroAssembler* masm() const {

    37     return _masm;

    38   }

    39 

    40  public:

    41   llvm::Value* base_pc() const {

    42     return _base_pc;

    43   }

    44   void set_base_pc(llvm::Value* base_pc) {

    45     assert(_base_pc == NULL, "only do this once");

    46     _base_pc = base_pc;

    47   }

    48 

    49   // Allocate some space in the buffer and return its address.

    50   // This buffer will have been relocated by the time the method

    51   // is installed, so you can't inline the result in code.

    52  public:

    53   void* malloc(size_t size) const {

    54     masm()->align(BytesPerWord);

    55     void *result = masm()->pc();

    56     masm()->advance(size);

    57     return result;

    58   }

    59 

    60   // Create a unique offset in the buffer.

    61  public:

    62   int create_unique_offset() const {

    63     int offset = masm()->offset();

    64     masm()->advance(1);

    65     return offset;

    66   }

    67 

    68   // Inline an oop into the buffer and return its offset.

    69  public:

    70   int inline_oop(jobject object) const {

    71     masm()->align(BytesPerWord);

    72     int offset = masm()->offset();

    73     masm()->store_oop(object);

    74     return offset;

    75   }

    76 

    77   // Inline a block of non-oop data into the buffer and return its offset.

    78  public:

    79   int inline_data(void *src, size_t size) const {

    80     masm()->align(BytesPerWord);

    81     int offset = masm()->offset();

    82     void *dst = masm()->pc();

    83     masm()->advance(size);

    84     memcpy(dst, src, size);

    85     return offset;

    86   }

    87 };