view src/cpu/sparc/vm/copy_sparc.hpp @ 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 d1605aabd0a1
children c18cbe5936b8 2d127394260e
line wrap: on
line source

/*
 * Copyright 2003-2008 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.
 *
 */

// Inline functions for memory copy and fill.

static void pd_conjoint_words(HeapWord* from, HeapWord* to, size_t count) {
  (void)memmove(to, from, count * HeapWordSize);
}

static void pd_disjoint_words(HeapWord* from, HeapWord* to, size_t count) {
  switch (count) {
  case 8:  to[7] = from[7];
  case 7:  to[6] = from[6];
  case 6:  to[5] = from[5];
  case 5:  to[4] = from[4];
  case 4:  to[3] = from[3];
  case 3:  to[2] = from[2];
  case 2:  to[1] = from[1];
  case 1:  to[0] = from[0];
  case 0:  break;
  default: (void)memcpy(to, from, count * HeapWordSize);
           break;
  }
}

static void pd_disjoint_words_atomic(HeapWord* from, HeapWord* to, size_t count) {
  switch (count) {
  case 8:  to[7] = from[7];
  case 7:  to[6] = from[6];
  case 6:  to[5] = from[5];
  case 5:  to[4] = from[4];
  case 4:  to[3] = from[3];
  case 3:  to[2] = from[2];
  case 2:  to[1] = from[1];
  case 1:  to[0] = from[0];
  case 0:  break;
  default: while (count-- > 0) {
             *to++ = *from++;
           }
           break;
  }
}

static void pd_aligned_conjoint_words(HeapWord* from, HeapWord* to, size_t count) {
  (void)memmove(to, from, count * HeapWordSize);
}

static void pd_aligned_disjoint_words(HeapWord* from, HeapWord* to, size_t count) {
  pd_disjoint_words(from, to, count);
}

static void pd_conjoint_bytes(void* from, void* to, size_t count) {
  (void)memmove(to, from, count);
}

static void pd_conjoint_bytes_atomic(void* from, void* to, size_t count) {
  (void)memmove(to, from, count);
}

static void pd_conjoint_jshorts_atomic(jshort* from, jshort* to, size_t count) {
  // FIXME
  (void)memmove(to, from, count << LogBytesPerShort);
}

static void pd_conjoint_jints_atomic(jint* from, jint* to, size_t count) {
  // FIXME
  (void)memmove(to, from, count << LogBytesPerInt);
}

static void pd_conjoint_jlongs_atomic(jlong* from, jlong* to, size_t count) {
#ifdef _LP64
  assert(BytesPerLong == BytesPerOop, "jlongs and oops must be the same size");
  pd_conjoint_oops_atomic((oop*)from, (oop*)to, count);
#else
  // Guarantee use of ldd/std via some asm code, because compiler won't.
  // See solaris_sparc.il.
  _Copy_conjoint_jlongs_atomic(from, to, count);
#endif
}

static void pd_conjoint_oops_atomic(oop* from, oop* to, size_t count) {
  // Do better than this: inline memmove body  NEEDS CLEANUP
  if (from > to) {
    while (count-- > 0) {
      // Copy forwards
      *to++ = *from++;
    }
  } else {
    from += count - 1;
    to   += count - 1;
    while (count-- > 0) {
      // Copy backwards
      *to-- = *from--;
    }
  }
}

static void pd_arrayof_conjoint_bytes(HeapWord* from, HeapWord* to, size_t count) {
  pd_conjoint_bytes_atomic(from, to, count);
}

static void pd_arrayof_conjoint_jshorts(HeapWord* from, HeapWord* to, size_t count) {
  pd_conjoint_jshorts_atomic((jshort*)from, (jshort*)to, count);
}

static void pd_arrayof_conjoint_jints(HeapWord* from, HeapWord* to, size_t count) {
  pd_conjoint_jints_atomic((jint*)from, (jint*)to, count);
}

static void pd_arrayof_conjoint_jlongs(HeapWord* from, HeapWord* to, size_t count) {
  pd_conjoint_jlongs_atomic((jlong*)from, (jlong*)to, count);
}

static void pd_arrayof_conjoint_oops(HeapWord* from, HeapWord* to, size_t count) {
  pd_conjoint_oops_atomic((oop*)from, (oop*)to, count);
}

static void pd_fill_to_words(HeapWord* tohw, size_t count, juint value) {
#ifdef _LP64
  guarantee(mask_bits((uintptr_t)tohw, right_n_bits(LogBytesPerLong)) == 0,
         "unaligned fill words");
  julong* to = (julong*)tohw;
  julong  v  = ((julong)value << 32) | value;
  while (count-- > 0) {
    *to++ = v;
  }
#else // _LP64
  juint* to = (juint*)tohw;
  while (count-- > 0) {
    *to++ = value;
  }
#endif // _LP64
}

static void pd_fill_to_aligned_words(HeapWord* tohw, size_t count, juint value) {
  assert(MinObjAlignmentInBytes == BytesPerLong, "need alternate implementation");

   julong* to = (julong*)tohw;
   julong  v  = ((julong)value << 32) | value;
   // If count is odd, odd will be equal to 1 on 32-bit platform
   // and be equal to 0 on 64-bit platform.
   size_t odd = count % (BytesPerLong / HeapWordSize) ;

   size_t aligned_count = align_object_size(count - odd) / HeapWordsPerLong;
   julong* end = ((julong*)tohw) + aligned_count - 1;
   while (to <= end) {
     DEBUG_ONLY(count -= BytesPerLong / HeapWordSize ;)
     *to++ = v;
   }
   assert(count == odd, "bad bounds on loop filling to aligned words");
   if (odd) {
     *((juint*)to) = value;

   }
}

static void pd_fill_to_bytes(void* to, size_t count, jubyte value) {
  (void)memset(to, value, count);
}

static void pd_zero_to_words(HeapWord* tohw, size_t count) {
  pd_fill_to_words(tohw, count, 0);
}

static void pd_zero_to_bytes(void* to, size_t count) {
  (void)memset(to, 0, count);
}