Pure SoA: NextID as Long

This is a leftover from an earlier implementation of pure SoA.
Our 39bit particle ids must be stored in an `amrex::Long`. An `int`
will crop them to 32bit range, which we quickly run out from.

Src/Particle/AMReX_ParticleTile.H

@@ -423,19 +423,19 @@ struct SoAParticle : SoAParticleBase
  return this->m_particle_tile_data.m_rdata[position_index][m_index];
  }
 
- static int NextID ();
+ static Long NextID ();
 
  /**
  * \brief This version can only be used inside omp critical.
  */
- static int UnprotectedNextID ();
+ static Long UnprotectedNextID ();
 
  /**
  * \brief Reset on restart.
  *
  * \param nextid
  */
- static void NextID (int nextid);
+ static void NextID (Long nextid);
 
 private :
 
@@ -449,7 +449,7 @@ private :
 template <int NArrayReal, int NArrayInt> int SoAParticle<NArrayReal, NArrayInt>::the_next_id = 1;
 
 template <int NArrayReal, int NArrayInt>
-int
+Long
 SoAParticle<NArrayReal, NArrayInt>::NextID ()
 {
  Long next;
@@ -466,14 +466,14 @@ SoAParticle<NArrayReal, NArrayInt>::NextID ()
  amrex::Abort("SoAParticle<NArrayReal, NArrayInt>::NextID() -- too many particles");
  }
 
- return int(next);
+ return next;
 }
 
 template <int NArrayReal, int NArrayInt>
-int
+Long
 SoAParticle<NArrayReal, NArrayInt>::UnprotectedNextID ()
 {
- int next = the_next_id++;
+ Long next = the_next_id++;
  if (next > LongParticleIds::LastParticleID) {
  amrex::Abort("SoAParticle<NArrayReal, NArrayInt>::NextID() -- too many particles");
  }
@@ -482,7 +482,7 @@ SoAParticle<NArrayReal, NArrayInt>::UnprotectedNextID ()
 
 template <int NArrayReal, int NArrayInt>
 void
-SoAParticle<NArrayReal, NArrayInt>::NextID (int nextid)
+SoAParticle<NArrayReal, NArrayInt>::NextID (Long nextid)
 {
  the_next_id = nextid;
 }