/*
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// ***********************************************************************
// 
// Moocho: Multi-functional Object-Oriented arCHitecture for Optimization
//                  Copyright (2003) Sandia Corporation
// 
// Under terms of Contract DE-AC04-94AL85000, there is a non-exclusive
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*/

#include "RTOp_TOp_axpy.h"
#include "RTOp_obj_value_vtbl.h"
#include "RTOp_obj_null_vtbl.h"

/* Implementation functions for RTOp_RTOp */

static int RTOp_TOp_axpy_apply_op(
  const struct RTOp_RTOp_vtbl_t* vtbl, const void* obj_data
  , const int num_vecs, const struct RTOp_SubVector vecs[]
  , const int num_targ_vecs, const struct RTOp_MutableSubVector targ_vecs[]
  , RTOp_ReductTarget targ_obj )
{
  RTOp_value_type alpha;
  RTOp_index_type        z_sub_dim;
  RTOp_value_type        *z_val;
  ptrdiff_t              z_val_s;
  RTOp_index_type        v0_sub_dim;
  const RTOp_value_type  *v0_val;
  ptrdiff_t              v0_val_s;
  register RTOp_index_type k;
  RTOp_value_type *z_val_tmp = NULL;
#ifdef RTOp_DEBUG
  RTOp_index_type i;
#endif

  /* */
  /* Validate the input */
  /* */
  if( num_vecs != 1 || vecs == NULL )
    return RTOp_ERR_INVALID_NUM_VECS;
  if( num_targ_vecs != 1 || targ_vecs == NULL )
    return RTOp_ERR_INVALID_NUM_TARG_VECS;
  if( targ_vecs[0].sub_dim != vecs[0].sub_dim )
    return RTOp_ERR_INCOMPATIBLE_VECS;

  /* */
  /* Get pointers to data */
  /* */

  /* alpha */
  alpha = *((RTOp_value_type*)obj_data);

  /* z */
  z_sub_dim      = targ_vecs[0].sub_dim;
  z_val          = targ_vecs[0].values;
  z_val_s        = targ_vecs[0].values_stride;

  /* v1 */
  v0_sub_dim     = vecs[0].sub_dim;
  v0_val         = vecs[0].values;
  v0_val_s       = vecs[0].values_stride;

  z_val_tmp = z_val;

  /* */
  /* Perform the operation */
  /* */

  /* Dense vector v[0] */
  if( z_val_s == 1 && v0_val_s == 1 ) {
    /* Slightly faster loop for unit stride vectors */
    for( k = 0; k < z_sub_dim; ++k )
      *z_val++ += alpha * (*v0_val++);
  }
  else {
    /* More general implementation for one or both non-unit strides */
    for( k = 0; k < z_sub_dim; ++k, z_val += z_val_s, v0_val += v0_val_s )
      *z_val += alpha * (*v0_val);
  }

  return 0; /* success? */
}

/* Virtual function table */
const struct RTOp_RTOp_vtbl_t RTOp_TOp_axpy_vtbl =
{
  &RTOp_obj_value_vtbl /* use simple scalar value type for object instance data */
  ,&RTOp_obj_null_vtbl /* use null type for target object */
  ,"TOp_axpy"
  ,NULL /* use default from reduct_vtbl */
  ,RTOp_TOp_axpy_apply_op
  ,NULL
  ,NULL
};

/* Class specific functions */

int RTOp_TOp_axpy_construct( RTOp_value_type alpha, struct RTOp_RTOp* op )
{
  op->vtbl = &RTOp_TOp_axpy_vtbl;
  op->vtbl->obj_data_vtbl->obj_create(NULL,NULL,&op->obj_data);
  *((RTOp_value_type*)op->obj_data) = alpha;
  return 0; /* success? */
}

int RTOp_TOp_axpy_destroy( struct RTOp_RTOp* op )
{
  op->vtbl->obj_data_vtbl->obj_free(NULL,NULL,&op->obj_data);
  op->vtbl      = NULL;
  return 0; /* success? */
}

int RTOp_TOp_axpy_set_alpha( RTOp_value_type alpha, struct RTOp_RTOp* op )
{
  *((RTOp_value_type*)op->obj_data) = alpha;
  return 0; /* success? */
}
