New Packages: gearshifft, clFFT (#4560)

Adds the `gearshifft` package, a benchmark suite for heterogeneous implementations of FFTs.
Adds clFFT, a software library containing FFT functions written in OpenCL.

see: https://github.com/clMathLibraries/clFFT

var/spack/repos/builtin/packages/clfft/package.py

@@ -0,0 +1,55 @@
+##############################################################################
+# Copyright (c) 2013-2017, Lawrence Livermore National Security, LLC.
+# Produced at the Lawrence Livermore National Laboratory.
+#
+# This file is part of Spack.
+# Created by Todd Gamblin, tgamblin@llnl.gov, All rights reserved.
+# LLNL-CODE-647188
+#
+# For details, see https://github.com/llnl/spack
+# Please also see the LICENSE file for our notice and the LGPL.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU Lesser General Public License (as
+# published by the Free Software Foundation) version 2.1, February 1999.
+#
+# This program is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the IMPLIED WARRANTY OF
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the terms and
+# conditions of the GNU Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public
+# License along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+##############################################################################
+from spack import *
+
+
+class Clfft(CMakePackage):
+    """a software library containing FFT functions written in OpenCL"""
+
+    homepage = "https://github.com/clMathLibraries/clFFT"
+    url      = "https://github.com/clMathLibraries/clFFT/archive/v2.12.2.tar.gz"
+
+    @property
+    def root_cmakelists_dir(self):
+        return join_path(self.stage.source_path, 'src')
+
+    version('2.12.2', '9104d85f9f2f3c58dd8efc0e4b06496f')
+
+    variant('client', default=True,
+            description='build client and callback client')
+
+    depends_on('opencl@1.2:')
+    depends_on('boost@1.33.0:', when='+client')
+
+    def cmake_args(self):
+        spec = self.spec
+
+        args = [
+            '-DBUILD_CLIENT:BOOL={0}'.format((
+                'ON' if '+client' in spec else 'OFF')),
+            '-DBUILD_CALLBACK_CLIENT:BOOL={0}'.format((
+                'ON' if '+client' in spec else 'OFF'))
+        ]
+        return args