/*

 * Copyright (c) 2018, Red Hat, Inc. All rights reserved.

 *

 * 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.

 *

 */

#include "precompiled.hpp"

#include "gc/shenandoah/shenandoahNumberSeq.hpp"

#include "runtime/atomic.hpp"

HdrSeq::HdrSeq() {

  _hdr = NEW_C_HEAP_ARRAY(int*, MagBuckets, mtInternal);

  for (int c = 0; c < MagBuckets; c++) {

    _hdr[c] = NULL;

  }

}

HdrSeq::~HdrSeq() {

  for (int c = 0; c < MagBuckets; c++) {

    int* sub = _hdr[c];

    if (sub != NULL) {

      FREE_C_HEAP_ARRAY(int, sub);

    }

  }

  FREE_C_HEAP_ARRAY(int*, _hdr);

}

void HdrSeq::add(double val) {

  if (val < 0) {

    assert (false, "value (%8.2f) is not negative", val);

    val = 0;

  }

  NumberSeq::add(val);

  double v = val;

  int mag;

  if (v > 0) {

    mag = 0;

    while (v > 1) {

      mag++;

      v /= 10;

    }

    while (v < 0.1) {

      mag--;

      v *= 10;

    }

  } else {

    mag = MagMinimum;

  }

  int bucket = -MagMinimum + mag;

  int sub_bucket = (int) (v * ValBuckets);

  // Defensively saturate for product bits:

  if (bucket < 0) {

    assert (false, "bucket index (%d) underflow for value (%8.2f)", bucket, val);

    bucket = 0;

  }

  if (bucket >= MagBuckets) {

    assert (false, "bucket index (%d) overflow for value (%8.2f)", bucket, val);

    bucket = MagBuckets - 1;

  }

  if (sub_bucket < 0) {

    assert (false, "sub-bucket index (%d) underflow for value (%8.2f)", sub_bucket, val);

    sub_bucket = 0;

  }

  if (sub_bucket >= ValBuckets) {

    assert (false, "sub-bucket index (%d) overflow for value (%8.2f)", sub_bucket, val);

    sub_bucket = ValBuckets - 1;

  }

  int* b = _hdr[bucket];

  if (b == NULL) {

    b = NEW_C_HEAP_ARRAY(int, ValBuckets, mtInternal);

    for (int c = 0; c < ValBuckets; c++) {

      b[c] = 0;

    }

    _hdr[bucket] = b;

  }

  b[sub_bucket]++;

}

double HdrSeq::percentile(double level) const {

  // target should be non-zero to find the first sample

  int target = MAX2(1, (int) (level * num() / 100));

  int cnt = 0;

  for (int mag = 0; mag < MagBuckets; mag++) {

    if (_hdr[mag] != NULL) {

      for (int val = 0; val < ValBuckets; val++) {

        cnt += _hdr[mag][val];

        if (cnt >= target) {

          return pow(10.0, MagMinimum + mag) * val / ValBuckets;

        }

      }

    }

  }

  return maximum();

}

BinaryMagnitudeSeq::BinaryMagnitudeSeq() {

  _mags = NEW_C_HEAP_ARRAY(size_t, BitsPerSize_t, mtInternal);

  for (int c = 0; c < BitsPerSize_t; c++) {

    _mags[c] = 0;

  }

  _sum = 0;

}

BinaryMagnitudeSeq::~BinaryMagnitudeSeq() {

  FREE_C_HEAP_ARRAY(size_t, _mags);

}

void BinaryMagnitudeSeq::add(size_t val) {

  Atomic::add(&_sum, val);

  int mag = log2_intptr(val) + 1;

  // Defensively saturate for product bits:

  if (mag < 0) {

    assert (false, "bucket index (%d) underflow for value (" SIZE_FORMAT ")", mag, val);

    mag = 0;

  }

  if (mag >= BitsPerSize_t) {

    assert (false, "bucket index (%d) overflow for value (" SIZE_FORMAT ")", mag, val);

    mag = BitsPerSize_t - 1;

  }

  Atomic::add(&_mags[mag], (size_t)1);

}

size_t BinaryMagnitudeSeq::level(int level) const {

  if (0 <= level && level < BitsPerSize_t) {

    return _mags[level];

  } else {

    return 0;

  }

}

size_t BinaryMagnitudeSeq::num() const {

  size_t r = 0;

  for (int c = 0; c < BitsPerSize_t; c++) {

    r += _mags[c];

  }

  return r;

}

size_t BinaryMagnitudeSeq::sum() const {

  return _sum;

}

int BinaryMagnitudeSeq::min_level() const {

  for (int c = 0; c < BitsPerSize_t; c++) {

    if (_mags[c] != 0) {

      return c;

    }

  }

  return BitsPerSize_t - 1;

}

int BinaryMagnitudeSeq::max_level() const {

  for (int c = BitsPerSize_t - 1; c > 0; c--) {

    if (_mags[c] != 0) {

      return c;

    }

  }

  return 0;

}