Mercurial > jdk8-mips64-public > hotspot / file revision

 /*

  * Copyright (c) 1997, 2004, 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.

  *

  */

 // Interface for updating the instruction cache.  Whenever the VM modifies

 // code, part of the processor instruction cache potentially has to be flushed.

 // Default implementation is in icache.cpp, and can be hidden per-platform.

 // Most platforms must provide only ICacheStubGenerator::generate_icache_flush().

 // Platforms that don't require icache flushing can just nullify the public

 // members of AbstractICache in their ICache class.  AbstractICache should never

 // be referenced other than by deriving the ICache class from it.

 //

 // The code for the ICache class and for generate_icache_flush() must be in

 // architecture-specific files, i.e., icache_<arch>.hpp/.cpp

 class AbstractICache : AllStatic {

  public:

   // The flush stub signature

   typedef int (*flush_icache_stub_t)(address addr, int lines, int magic);

  protected:

   // The flush stub function address

   static flush_icache_stub_t _flush_icache_stub;

   // Call the flush stub

   static void call_flush_stub(address start, int lines);

  public:

   enum {

     stub_size      = 0, // Size of the icache flush stub in bytes

     line_size      = 0, // Icache line size in bytes

     log2_line_size = 0  // log2(line_size)

   };

   static void initialize();

   static void invalidate_word(address addr);

   static void invalidate_range(address start, int nbytes);

 };

 // Must be included before the definition of ICacheStubGenerator

 // because ICacheStubGenerator uses ICache definitions.

 #include "incls/_icache_pd.hpp.incl"

 class ICacheStubGenerator : public StubCodeGenerator {

  public:

   ICacheStubGenerator(CodeBuffer *c) : StubCodeGenerator(c) {}

   // Generate the icache flush stub.

   //

   // Since we cannot flush the cache when this stub is generated,

   // it must be generated first, and just to be sure, we do extra

   // work to allow a check that these instructions got executed.

   //

   // The flush stub has three parameters (see flush_icache_stub_t).

   //

   //   addr  - Start address, must be aligned at log2_line_size

   //   lines - Number of line_size icache lines to flush

   //   magic - Magic number copied to result register to make sure

   //           the stub executed properly

   //

   // A template for generate_icache_flush is

   //

   //    #define __ _masm->

   //

   //    void ICacheStubGenerator::generate_icache_flush(

   //      ICache::flush_icache_stub_t* flush_icache_stub

   //    ) {

   //      StubCodeMark mark(this, "ICache", "flush_icache_stub");

   //

   //      address start = __ pc();

   //

   //      // emit flush stub asm code

   //

   //      // Must be set here so StubCodeMark destructor can call the flush stub.

   //      *flush_icache_stub = (ICache::flush_icache_stub_t)start;

   //    };

   //

   //    #undef __

   //

   // The first use of flush_icache_stub must apply it to itself.  The

   // StubCodeMark destructor in generate_icache_flush will call Assembler::flush,

   // which in turn will call invalidate_range (see asm/assembler.cpp), which

   // in turn will call the flush stub *before* generate_icache_flush returns.

   // The usual method of having generate_icache_flush return the address of the

   // stub to its caller, which would then, e.g., store that address in

   // flush_icache_stub, won't work.  generate_icache_flush must itself set

   // flush_icache_stub to the address of the stub it generates before

   // the StubCodeMark destructor is invoked.

   void generate_icache_flush(ICache::flush_icache_stub_t* flush_icache_stub);

 };