pp2026-hw1/part1/vectorOP.cpp

#include "PPintrin.h"
#include <algorithm>
#include <iostream>

// implementation of absSerial(), but it is vectorized using PP intrinsics
void absVector(float *values, float *output, int N)
{
  __pp_vec_float x;
  __pp_vec_float result;
  __pp_vec_float zero = _pp_vset_float(0.f);
  __pp_mask maskAll, maskIsNegative, maskIsNotNegative;

  //  Note: Take a careful look at this loop indexing.  This example
  //  code is not guaranteed to work when (N % VECTOR_WIDTH) != 0.
  //  Why is that the case?
  for (int i = 0; i < N; i += VECTOR_WIDTH)
  {

    // All ones
    maskAll = _pp_init_ones();

    // All zeros
    maskIsNegative = _pp_init_ones(0);

    // Load vector of values from contiguous memory addresses
    _pp_vload_float(x, values + i, maskAll); // x = values[i];

    // Set mask according to predicate
    _pp_vlt_float(maskIsNegative, x, zero, maskAll); // if (x < 0) {

    // Execute instruction using mask ("if" clause)
    _pp_vsub_float(result, zero, x, maskIsNegative); //   output[i] = -x;

    // Inverse maskIsNegative to generate "else" mask
    maskIsNotNegative = _pp_mask_not(maskIsNegative); // } else {

    // Execute instruction ("else" clause)
    _pp_vload_float(result, values + i, maskIsNotNegative); //   output[i] = x; }

    // Write results back to memory
    _pp_vstore_float(output + i, result, maskAll);
  }
}

void clampedExpVector(float *values, int *exponents, float *output, int N)
{
  //
  // PP STUDENTS TODO: Implement your vectorized version of
  // clampedExpSerial() here.
  //
  // Your solution should work for any value of
  // N and VECTOR_WIDTH, not just when VECTOR_WIDTH divides N
  //
  __pp_vec_float x;
  __pp_vec_int y;
  __pp_vec_float result;
  __pp_vec_int zero = _pp_vset_int(0);
  __pp_vec_float cap = _pp_vset_float(9.999999f);
  __pp_vec_int one = _pp_vset_int(1);
  __pp_mask maskAll, maskNonZero, maskGreater;
  maskAll = _pp_init_ones();

  for (int i = 0; i < N; i += VECTOR_WIDTH)
  {
    if (i + VECTOR_WIDTH > N) {
      float *tmp = new float[VECTOR_WIDTH];
      for (int j = 0; i + j < N; j++)
        tmp[j] = values[i+j];
      for (int j = N % VECTOR_WIDTH; j < VECTOR_WIDTH; j++)
        tmp[j] = 0;
      _pp_vload_float(x, tmp, maskAll);
      delete []tmp;
    } else {
      _pp_vload_float(x, values + i, maskAll); // x = values[i];
    }

    if (i + VECTOR_WIDTH > N) {
      int *tmp = new int[VECTOR_WIDTH];
      for (int j = 0; i + j < N; j++)
        tmp[j] = exponents[i+j];
      for (int j = N % VECTOR_WIDTH; j < VECTOR_WIDTH; j++)
        tmp[j] = 0;
      _pp_vload_int(y, tmp, maskAll);
      delete []tmp;
    } else {
      _pp_vload_int(y, exponents + i, maskAll); // y = exponents[i];
    }

    cout << "min exponents: " << *min_element(y.value, y.value+VECTOR_WIDTH) << endl;
    cout << "max exponents: " << *max_element(y.value, y.value+VECTOR_WIDTH) << endl;

    _pp_vset_float(result, 1.f, maskAll);
    maskNonZero = _pp_init_ones();
    while (_pp_cntbits(maskNonZero) > 0) {
      _pp_veq_int(maskNonZero, y, zero, maskAll);
      maskNonZero = _pp_mask_not(maskNonZero);

      _pp_vmult_float(result, result, x, maskNonZero);
      _pp_vsub_int(y, y, one, maskNonZero);
    }

    _pp_vgt_float(maskGreater, result, cap, maskAll);
    _pp_vset_float(result, 9.999999f, maskGreater);

    if (i + VECTOR_WIDTH > N) {
      float *tmp = new float[VECTOR_WIDTH];
      _pp_vstore_float(tmp, result, maskAll);
      for (int j = 0; i + j < N; j++)
        output[i+j] = tmp[j];
      delete []tmp;
    } else {
      _pp_vstore_float(output + i, result, maskAll);
    }
  }
}

// returns the sum of all elements in values
// You can assume N is a multiple of VECTOR_WIDTH
// You can assume VECTOR_WIDTH is a power of 2
float arraySumVector(float *values, int N)
{

  //
  // PP STUDENTS TODO: Implement your vectorized version of arraySumSerial here
  //
  __pp_vec_float x;
  __pp_mask maskAll;
  maskAll = _pp_init_ones();

  float total = 0.f;
  for (int i = 0; i < N; i += VECTOR_WIDTH)
  {
    _pp_vload_float(x, values + i, maskAll);

    for (int n = VECTOR_WIDTH; n > 1; n >>= 1) {
      _pp_hadd_float(x, x);
      _pp_interleave_float(x, x);
    }

    float *tmp = new float[VECTOR_WIDTH];
    _pp_vstore_float(tmp, x, maskAll);
    total += tmp[0];
    delete []tmp;
  }

  return total;
}