view src/cpu/sparc/vm/icBuffer_sparc.cpp @ 453:c96030fff130

6684579: SoftReference processing can be made more efficient Summary: For current soft-ref clearing policies, we can decide at marking time if a soft-reference will definitely not be cleared, postponing the decision of whether it will definitely be cleared to the final reference processing phase. This can be especially beneficial in the case of concurrent collectors where the marking is usually concurrent but reference processing is usually not. Reviewed-by: jmasa
author ysr
date Thu, 20 Nov 2008 16:56:09 -0800
parents a61af66fc99e
children 6b2273dd6fa9
line wrap: on
line source

/*
 * Copyright 1997-2006 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 *
 */

#include "incls/_precompiled.incl"
#include "incls/_icBuffer_sparc.cpp.incl"

int InlineCacheBuffer::ic_stub_code_size() {
#ifdef _LP64
  if (TraceJumps) return 600 * wordSize;
  return (NativeMovConstReg::instruction_size +  // sethi;add
          NativeJump::instruction_size +          // sethi; jmp; delay slot
          (1*BytesPerInstWord) + 1);            // flush + 1 extra byte
#else
  if (TraceJumps) return 300 * wordSize;
  return (2+2+ 1) * wordSize + 1; // set/jump_to/nop + 1 byte so that code_end can be set in CodeBuffer
#endif
}

void InlineCacheBuffer::assemble_ic_buffer_code(address code_begin, oop cached_oop, address entry_point) {
  ResourceMark rm;
  CodeBuffer     code(code_begin, ic_stub_code_size());
  MacroAssembler* masm            = new MacroAssembler(&code);
  // note: even though the code contains an embedded oop, we do not need reloc info
  // because
  // (1) the oop is old (i.e., doesn't matter for scavenges)
  // (2) these ICStubs are removed *before* a GC happens, so the roots disappear
  assert(cached_oop == NULL || cached_oop->is_perm(), "must be old oop");
  Address cached_oop_addr(G5_inline_cache_reg, address(cached_oop));
  // Force the sethi to generate the fixed sequence so next_instruction_address works
  masm->sethi(cached_oop_addr, true /* ForceRelocatable */ );
  masm->add(cached_oop_addr, G5_inline_cache_reg);
  assert(G3_scratch != G5_method, "Do not clobber the method oop in the transition stub");
  assert(G3_scratch != G5_inline_cache_reg, "Do not clobber the inline cache register in the transition stub");
  Address entry(G3_scratch, entry_point);
  masm->JUMP(entry, 0);
  masm->delayed()->nop();
  masm->flush();
}


address InlineCacheBuffer::ic_buffer_entry_point(address code_begin) {
  NativeMovConstReg* move = nativeMovConstReg_at(code_begin);   // creation also verifies the object
  NativeJump*        jump = nativeJump_at(move->next_instruction_address());
  return jump->jump_destination();
}


oop InlineCacheBuffer::ic_buffer_cached_oop(address code_begin) {
  NativeMovConstReg* move = nativeMovConstReg_at(code_begin);   // creation also verifies the object
  NativeJump*        jump = nativeJump_at(move->next_instruction_address());
  return (oop)move->data();
}