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For the Intel compiler, this was assured with the pragma

  !DEC$ ATTRIBUTES ALIGN: 64:: a

however, other compilers such as gcc of course did not honour this,
which could result in SIGSEGVs in case the variable was not aligned to
32 bytes (by chance!).

This fixes issue #11, thanks to Nico Holmberg for reporting this.

The SSE kernels with blocking of 2,4,6 (real case) and 1,2 (complex)
case are now available by default

Thus the following changes have been done
- introduce new macros in configure.ac and Makefile.am
- renmae the AVX kernels in AVX_AVX2 (they also support AVX2)
- introduce new files with SSE kernel
- introduce new kernel parameters !
- make the SSE kernels callable

The results are identical with previous kernels

- The SSE part will be available in different files.
- Specify whether AVX or AVX2 was used to build

The test programs include the same template now, the
printed messages are thus unified

The configure flag "--enable-shared-memory-only" triggers a build
of ELPA without MPI support:

- all MPI calls are skipped (or overloaded)
- all calls to scalapack functions are replaced by the corresponding
  lapack calls
- all calls to blacs are skipped

Using ELPA without MPI gives the same results as using ELPA with 1 MPI
task!

This version is not yet optimized for performance, here and there some
unecessary copies are done.

Ths version is intended for users, who do not have MPI in their
application but still would like to use ELPA on one compute node

The generic real kernel is now contained in a module, this allows
strict interface checking! It also does not use assumed size arrays
anymore. Both points increase the possibility to debug and find errors.

However, this might be performance critical! It is possible to
switch back to the old implementation if that turns out to
be beneficial w.r.t. performance. Timings with gfortran 4.9 on Intel
Haswell showed that the new implementation is about 30 percent faster
then the previous one

Now all functions, which were "contained" in anoter one are moved
to seperate modules. This allows for strict interface checking and
debugging

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

The Fortran variable declerations "variable type*[4,8,16]" is non
Fortran standard. It might cause problem in the future.
Furthermore, the usage of Fortran and C togehther is more clean
if variables are defined according to C variable types.

This is done, now for all the test programs

This commit does not change the interfaces defined in ELPA_2015.11.001 !
All functionality is available via the interface names and definitions
as in ELPA_2015.11.001

But some new interfaces have been added, in order to unfiy the
references from C and Fortran codes:

- The procedures to create the ELPA (row/column) communicators are now
  available from C _and_ Fortran with the name "get_elpa_communicators".
  The old Fortran name "get_elpa_row_col_comms" and the old C name
  "elpa_get_communicators" are from now on deprecated but still available

- The 1-stage solver routines are available from C _and_ Fortran via
  the names "solve_evp_real_1stage" and "solve_evp_complex_1stage".
  The old Fortran names "solve_evp_real" and "solve_evp_complex" are
  from now on deprecated but still functional.

All documentation (man pages, doxygen, and example test programs) have
been changed accordingly.

This commit implies a change in the API versioning number, but no
changes to codes calling ELPA (if they have been already updated to the
API of ELPA_2015.11.001)

For the library functions which are accessible by the user
man pages decribing the Fortran and C interface exist:

-get_elpa_row_comms
-solve_evp_real , solve_evp_complex
-solve_evp_real_2stage, solve_evp_complex_2stage

For the "service binary" print_available_elpa2_kernels,
also a man page exists.

TODO: extend man pages to test-binaries, or do not install test-binaries

The user functions of ELPA are now documented with doxygen tags.
At the moment the interface of ELPA 2015.11.001 is decribed.

The documentation has step by step to be implemented for all functions
and test programms.

As in a previous commit for elpa1.F90, for automatic generation of
documentation elpa2.F90 has been splitted in two files, in order to
have a lean, easy-to-understand user interface:

elpa2.F90
the visible user functions, which provide the library calls.
The usage is the same as before

elpa2_compute.F90
all internal routines, which are used by ELPA2, but which are never
called external of the library by a user. These functions are now
"hidden" in the module elpa2_compute, which is used by ELPA2.

The procedures in elpa2_compute.F90 are identical to the ones in
elpa2.F90 before this split commit. The only -- but quite a lot of them
-- changes are intendation changes.

For automatic generation of documentation, the file elpa1.F90
has been splitted into two files, in order to have a lean,
easy-to-understand user interface:

elpa1.F90
the visible user functios, which provide the library calls.
The usage is the same as always

elpa1_compute.F90
all internal routines, which are used by ELPA1 and ELPA2, but
which are never called by the user. These functions are now "hidden"
in the module elpa1_compute, which is used by ELPA1 and ELPA2.

The procedures in elpa1_compute.F90 are identical to the ones in
elpa1.F90 before this split commit. The only -- but lot of --
changes are intendation.

Due to the efforts of Intel, ELPA features now build-in
support of AVX2 and FMA for the latest Intel processors

The examples, how to invoke ELPA from a c program have been updated.
There are now examples for ELPA1 and ELPA2 both real and complex case.
The test cases are still with less functionality than their Fortran
counter parts, they are just ment as a "proof-of-concept".

C interfaces are now available and definied in the header
elpa.h

If the QR-decomposition is used wrongly (matrix size is not a
multiple of block size) the the execution will abort, in
order to prevent the wrong results, discussed in a previous commit

Debug messages are now available by setting the environment variable
"ELPA_DEBUG_MESSAGES" to "yes".

It contains preprocessor directives which produce warnings or errors
otherwise.

The qr decomposition is now available as a runtime choice.
Some testing has still to be done

At build time it can be specified that the ELPA test
programs give more detailed timing information, which
is usefull for performace measurements

If specified in the configure step, the test programs
redirect their stdout and stderr output of each MPI
task in a seperate file, which will be stored in a
subdirectory "mpi_stdout".

This will only be done if the environment variable
"REDIRECT_ELPA_TEST_OUTPUT" is set to "true"