Put routine single_hh_trafo in a module

This routine has been contained in a subroutine.
It has been moved to a module and and renamed to
"single_hh_trafo_real" to make it's intention more clear

Makefile.am

@@ -15,6 +15,7 @@ libelpa@SUFFIX@_la_SOURCES = src/mod_precision.f90 \
 	                     src/elpa1.F90 \
 			     src/elpa2_utilities.F90 \
 			     src/mod_pack_unpack_real.F90 \
+			     src/elpa2_kernels/mod_single_hh_trafo_real.F90 \
 			     src/mod_pack_unpack_complex.F90 \
 			     src/elpa2_compute.F90 \
 			     src/elpa2.F90 \

src/elpa2_compute.F90

@@ -2463,6 +2463,7 @@ module ELPA2_compute
 #endif
 
          use precision
+         use single_hh_trafo_real
 #if defined(WITH_REAL_GENERIC_SIMPLE_KERNEL)
          use real_generic_simple_kernel, only : double_hh_trafo_generic_simple
 #endif
@@ -2652,12 +2653,12 @@ module ELPA2_compute
 !#endif
 
 #ifdef WITH_OPENMP
-           if (j==1) call single_hh_trafo(a(1,1+off+a_off,istripe,my_thread), &
-                                      bcast_buffer(1,off+1), nbw, nl,     &
+           if (j==1) call single_hh_trafo_real_cpu_openmp(a(1:stripe_width,1+off+a_off:1+off_a_off+nbw-1,istripe,my_thread), &
+                                      bcast_buffer(1:nbw,off+1), nbw, nl,     &
                                       stripe_width)
 #else
-           if (j==1) call single_hh_trafo(a(1,1+off+a_off,istripe),           &
-                                      bcast_buffer(1,off+1), nbw, nl,     &
+           if (j==1) call single_hh_trafo_real_cpu(a(1:stripe_width,1+off+a_off:1+off+a_off+nbw-1,istripe),           &
+                                      bcast_buffer(1:nbw,off+1), nbw, nl,     &
                                       stripe_width)
 #endif
 
@@ -2698,11 +2699,11 @@ module ELPA2_compute
 #endif
            enddo
 #ifdef WITH_OPENMP
-           if (jj==1) call single_hh_trafo(a(1,1+off+a_off,istripe,my_thread), &
-                                          bcast_buffer(1,off+1), nbw, nl, stripe_width)
+           if (jj==1) call single_hh_trafo_real_cpu_openmp(a(1:stripe_width,1+off+a_off:1+off+a_off+nbw-1,istripe,my_thread), &
+                                          bcast_buffer(1:nbw,off+1), nbw, nl, stripe_width)
 #else
-           if (jj==1) call single_hh_trafo(a(1,1+off+a_off,istripe), &
-                                          bcast_buffer(1,off+1), nbw, nl, stripe_width)
+           if (jj==1) call single_hh_trafo_real_cpu(a(1:stripe_width,1+off+a_off:1+off+a_off+nbw-1,istripe), &
+                                          bcast_buffer(1:nbw,off+1), nbw, nl, stripe_width)
 #endif
 #if defined(WITH_NO_SPECIFIC_REAL_KERNEL)
          endif
@@ -2755,11 +2756,11 @@ module ELPA2_compute
 #endif
            enddo
 #ifdef WITH_OPENMP
-           if (jjj==1) call single_hh_trafo(a(1,1+off+a_off,istripe,my_thread), &
-                                           bcast_buffer(1,off+1), nbw, nl, stripe_width)
+           if (jjj==1) call single_hh_trafo_real_cpu_openmp(a(1:stripe_width,1+off+a_off:1+off+a_off+nbw-1,istripe,my_thread), &
+                                           bcast_buffer(1:nbw,off+1), nbw, nl, stripe_width)
 #else
-           if (jjj==1) call single_hh_trafo(a(1,1+off+a_off,istripe), &
-                                           bcast_buffer(1,off+1), nbw, nl, stripe_width)
+           if (jjj==1) call single_hh_trafo_real_cpu(a(1:stripe_width,1+off+a_off:1+off+a_off+nbw-1,istripe), &
+                                           bcast_buffer(1:nbw,off+1), nbw, nl, stripe_width)
 #endif
 #if defined(WITH_NO_SPECIFIC_REAL_KERNEL)
          endif

src/elpa2_kernels/mod_single_hh_trafo_real.F90

+module single_hh_trafo_real
+  implicit none
+#include "config-f90.h"
+
+#ifdef WITH_OPENMP
+  public single_hh_trafo_real_cpu_openmp
+#else
+  public single_hh_trafo_real_cpu
+#endif
+  contains
+
+#ifdef WITH_OPENMP
+    subroutine single_hh_trafo_real_cpu_openmp(q, hh, nb, nq, ldq)
+#else
+    subroutine single_hh_trafo_real_cpu(q, hh, nb, nq, ldq)
+#endif
+
+#ifdef HAVE_DETAILED_TIMINGS
+      use timings
+#endif
+      use precision
+      ! Perform single real Householder transformation.
+      ! This routine is not performance critical and thus it is coded here in Fortran
+
+      implicit none
+      integer(kind=ik), intent(in)   :: nb, nq, ldq
+!      real(kind=rk), intent(inout)   :: q(ldq, *)
+!      real(kind=rk), intent(in)      :: hh(*)
+      real(kind=rk), intent(inout)   :: q(1:ldq, 1:nb)
+      real(kind=rk), intent(in)      :: hh(1:nb)
+      integer(kind=ik)               :: i
+      real(kind=rk)                  :: v(nq)
+
+#ifdef HAVE_DETAILED_TIMINGS
+#ifdef WITH_OPENMP
+      call timer%start("single_hh_trafo_real_cpu_openmp")
+#else
+      call timer%start("single_hh_trafo_real_cpu")
+#endif
+#endif
+
+      ! v = q * hh
+      v(:) = q(1:nq,1)
+      do i=2,nb
+        v(:) = v(:) + q(1:nq,i) * hh(i)
+      enddo
+
+      ! v = v * tau
+      v(:) = v(:) * hh(1)
+
+      ! q = q - v * hh**T
+      q(1:nq,1) = q(1:nq,1) - v(:)
+      do i=2,nb
+        q(1:nq,i) = q(1:nq,i) - v(:) * hh(i)
+      enddo
+
+#ifdef HAVE_DETAILED_TIMINGS
+#ifdef WITH_OPENMP
+      call timer%stop("single_hh_trafo_real_cpu_openmp")
+#else
+      call timer%stop("single_hh_trafo_real_cpu")
+#endif
+#endif
+    end subroutine
+
+
+end module