/*

 * 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.

 *

 */

// Inline functions for memory copy and fill.

static void pd_conjoint_words(const HeapWord* from, HeapWord* to, size_t count) {

  (void)memmove(to, from, count * HeapWordSize);

}

static void pd_disjoint_words(const 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(const 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(const HeapWord* from, HeapWord* to, size_t count) {

  (void)memmove(to, from, count * HeapWordSize);

}

static void pd_aligned_disjoint_words(const HeapWord* from, HeapWord* to, size_t count) {

  pd_disjoint_words(from, to, count);

}

static void pd_conjoint_bytes(const void* from, void* to, size_t count) {

  (void)memmove(to, from, count);

}

static void pd_conjoint_bytes_atomic(const void* from, void* to, size_t count) {

  (void)memmove(to, from, count);

}

static void pd_conjoint_jshorts_atomic(const jshort* from, jshort* to, size_t count) {

  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_conjoint_jints_atomic(const jint* from, jint* to, size_t count) {

  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_conjoint_jlongs_atomic(const jlong* from, jlong* to, size_t count) {

  assert(BytesPerLong == BytesPerOop, "jlongs and oops must be the same size");

  pd_conjoint_oops_atomic((const oop*)from, (oop*)to, count);

}

static void pd_conjoint_oops_atomic(const 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(const HeapWord* from, HeapWord* to, size_t count) {

  pd_conjoint_bytes_atomic(from, to, count);

}

static void pd_arrayof_conjoint_jshorts(const HeapWord* from, HeapWord* to, size_t count) {

  pd_conjoint_jshorts_atomic((const jshort*)from, (jshort*)to, count);

}

static void pd_arrayof_conjoint_jints(const HeapWord* from, HeapWord* to, size_t count) {

  pd_conjoint_jints_atomic((const jint*)from, (jint*)to, count);

}

static void pd_arrayof_conjoint_jlongs(const HeapWord* from, HeapWord* to, size_t count) {

  pd_conjoint_jlongs_atomic((const jlong*)from, (jlong*)to, count);

}

static void pd_arrayof_conjoint_oops(const HeapWord* from, HeapWord* to, size_t count) {

  pd_conjoint_oops_atomic((const oop*)from, (oop*)to, count);

}

static void pd_fill_to_words(HeapWord* tohw, size_t count, juint value) {

  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;

  }

}

typedef void (*_zero_Fn)(HeapWord* to, size_t count);

// Only used for heap objects, so align_object_offset.

// All other platforms pd_fill_to_aligned_words simply calls pd_fill_to_words, don't

// know why this one is different.

static void pd_fill_to_aligned_words(HeapWord* tohw, size_t count, juint value) {

  assert(MinObjAlignmentInBytes >= BytesPerLong, "need alternate implementation");

  if (value == 0 && UseBlockZeroing &&

      (count > (size_t)(BlockZeroingLowLimit >> LogHeapWordSize))) {

   // Call it only when block zeroing is used

   ((_zero_Fn)StubRoutines::zero_aligned_words())(tohw, count);

  } else {

   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_offset(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);

}