# Copyright (c) 2016 Dave Love, Liverpool University
# Licence: MIT

%global sover 3
%global gslsover 0

# Ensure we're installable in case the Intel rpms haven't been
# installed locally (typical shared HPC setup).
%global __requires_exclude \(libmkl*\)
%{?filter_setup:
%filter_from_requires /libmkl*/d
%filter_setup
}

Name:		mkl-compat
Version:	1.0
Release:	1%{?dist}
Summary:	MKL compatibility libraries for reference blas/lapack etc.
License:	MIT
# I don't know the appropriate link incantation for ix86 anyhow.
ExclusiveArch:  x86_64

%description

This package provides trivial shared LAPACK/BLAS libraries which can
replace those from the reference blas, lapack, atlas, gsl, and R
packages at run time so that binaries dynamically linked against those
automatically call into the (proprietary :-() Intel MKL library
instead.  (This is primarily for testing, or production use on systems
with AVX512, since OpenBLAS, via the openblas-compat package is fine
for other x86 systems but unfortunately doesn't currently have AVX512
support.)

It is similar in effect to openblas-compat (q.v.), but doesn't affect
the load path by default (set LD_LIBRARY_PATH and/or R_LD_LIBRARY_PATH
to pick up %_libdir/%name).  Also it only provides OpenMP substitutes,
even for the serial libraries -- set OMP_NUM_THREADS as appropriate,
e.g. 1 to avoid multiple threads.  The library shims set rpath to the
MKL location with which they were built, but obviously you need to
have MKL installed and LD_LIBRARY_PATH set appropriately if the MKL
build and run time locations differ.


%prep
rm -rf %name-%version
mkdir %name-%version

%build

if [[ -z $MKLROOT ]]; then
  echo "MKLROOT not defined, e.g. by environment module" >&2
  exit 1
fi

# Idea: we could have dummy libmkl_intel_lp64 etc. at build time to
# allow building without anything proprietary, but then we'd have to
# know what MKLROOT should be to avoid needing LD_LIBRARY_PATH and
# rather defeating the object.
%global mkl_flags -Wl,--no-as-needed -L$MKLROOT/lib/intel64 -lmkl_intel_lp64 -lmkl_core -lmkl_gnu_thread -fopenmp -Wl,-rpath=$MKLROOT/lib/intel64


cd %name-%version
# We need libraries with the right filename and soname, so build
# trivial ones which just pull in openblas.  (Debian builds
# non-trivial versions as alternatives.)
%if 0%{?__isa_bits} == 64
%global lib64s blas64 lapack64
%else
%global lib64s %nil
%endif
# ATLAS changed at 3.10
%if 0%{?el6} || 0%{?el5}
%global atlibs cblas clapack f77blas
%else
%global atlibs satlas
%endif
for n in blas lapack lapacke %lib64s %atlibs openblas openblaso; do
  cc -shared -o lib$n.so.%sover -Wl,-soname,lib$n.so.%sover %mkl_flags
done
cc -shared -o libgslcblas.so.%gslsover -Wl,-soname,libgslcblas.so.%gslsover %mkl_flags

# atlas threaded
%if 0%{?fedora} > 20
cc -shared -o libtatlas.so.%sover -Wl,-soname,libtatlas.so.%sover %mkl_flags
%else
for n in ptf77blas ptcblas; do
  cc -shared -o lib$n.so.%sover -Wl,-soname,lib$n.so.%sover %mkl_flags
done
%endif

# R sanctions linking optimized libraries to these in its library
# area, but that gets a spurious link made by ldconfig and this is
# cleaner and robust through package updates.
cc -shared -o libRblas.so %mkl_flags
cc -shared -o libRlapack.so %mkl_flags


%install
cd %name-%version
mkdir -p %buildroot%_libdir/%name
install -m 755 *.so* %buildroot%_libdir/%name


%files
%_libdir/%name


%changelog
* Thu Oct 20 2016 Dave Love <loveshack@fedoraproject.org> - 1.0-1
- Initial version