Add support for IBM threaded compilers: xl*_r (#2894)

* Add support for IBM threaded compilers, xl*_r

Added new compiler class, xl_r; added default flags to the compilers.yaml file.

* Add cppflags to the set of default flags to be added to the compilers stanza in compiler.yaml.

These flags are optional. Only defined flags will be listed in the compilers.yaml file.

* Fix scripting warnings revealed by flake8.

Updated __init__.py and xl_r.py to conform with flake8 rules.

* Add justification to the definition of the XL default compiler flags.

8 files changed, 158 insertions, 9 deletions

diff --git a/lib/spack/env/cc b/lib/spack/env/cc
index c4e51834a5..c0e97f3416 100755
--- a/lib/spack/env/cc
+++ b/lib/spack/env/cc
@@ -98,25 +98,25 @@ case "$command" in
     cpp)
         mode=cpp
         ;;
-    cc|c89|c99|gcc|clang|icc|pgcc|xlc)
+    cc|c89|c99|gcc|clang|icc|pgcc|xlc|xlc_r)
         command="$SPACK_CC"
         language="C"
         comp="CC"
         lang_flags=C
         ;;
-    c++|CC|g++|clang++|icpc|pgc++|xlc++)
+    c++|CC|g++|clang++|icpc|pgc++|xlc++|xlc++_r)
         command="$SPACK_CXX"
         language="C++"
         comp="CXX"
         lang_flags=CXX
         ;;
-    ftn|f90|fc|f95|gfortran|ifort|pgfortran|xlf90|nagfor)
+    ftn|f90|fc|f95|gfortran|ifort|pgfortran|xlf90|xlf90_r|nagfor)
         command="$SPACK_FC"
         language="Fortran 90"
         comp="FC"
         lang_flags=F
         ;;
-    f77|gfortran|ifort|pgfortran|xlf|nagfor|ftn)
+    f77|gfortran|ifort|pgfortran|xlf|xlf_r|nagfor|ftn)
         command="$SPACK_F77"
         language="Fortran 77"
         comp="F77"
diff --git a/lib/spack/env/xl_r/xlc++_r b/lib/spack/env/xl_r/xlc++_r
new file mode 120000
index 0000000000..82c2b8e90a
--- /dev/null
+++ b/lib/spack/env/xl_r/xlc++_r
@@ -0,0 +1 @@
+../cc
\ No newline at end of file
diff --git a/lib/spack/env/xl_r/xlc_r b/lib/spack/env/xl_r/xlc_r
new file mode 120000
index 0000000000..82c2b8e90a
--- /dev/null
+++ b/lib/spack/env/xl_r/xlc_r
@@ -0,0 +1 @@
+../cc
\ No newline at end of file
diff --git a/lib/spack/env/xl_r/xlf90_r b/lib/spack/env/xl_r/xlf90_r
new file mode 120000
index 0000000000..82c2b8e90a
--- /dev/null
+++ b/lib/spack/env/xl_r/xlf90_r
@@ -0,0 +1 @@
+../cc
\ No newline at end of file
diff --git a/lib/spack/env/xl_r/xlf_r b/lib/spack/env/xl_r/xlf_r
new file mode 120000
index 0000000000..82c2b8e90a
--- /dev/null
+++ b/lib/spack/env/xl_r/xlf_r
@@ -0,0 +1 @@
+../cc
\ No newline at end of file
diff --git a/lib/spack/spack/compilers/__init__.py b/lib/spack/spack/compilers/__init__.py
index 6e65f50269..731acaf9c2 100644
--- a/lib/spack/spack/compilers/__init__.py
+++ b/lib/spack/spack/compilers/__init__.py
@@ -40,6 +40,7 @@ from spack.util.naming import mod_to_class
 
 _imported_compilers_module = 'spack.compilers'
 _path_instance_vars = ['cc', 'cxx', 'f77', 'fc']
+_flags_instance_vars = ['cflags', 'cppflags', 'cxxflags', 'fflags']
 _other_instance_vars = ['modules', 'operating_system', 'environment',
                         'extra_rpaths']
 _cache_config_file = []
@@ -60,6 +61,9 @@ def _to_dict(compiler):
     d['paths'] = dict((attr, getattr(compiler, attr, None))
                       for attr in _path_instance_vars)
     d['flags'] = dict((fname, fvals) for fname, fvals in compiler.flags)
+    d['flags'].update(dict((attr, getattr(compiler, attr, None))
+                      for attr in _flags_instance_vars
+                           if hasattr(compiler, attr)))
     d['operating_system'] = str(compiler.operating_system)
     d['target'] = str(compiler.target)
     d['modules'] = compiler.modules if compiler.modules else []
diff --git a/lib/spack/spack/compilers/xl.py b/lib/spack/spack/compilers/xl.py
index f4b7c4237d..77a5ed7acd 100644
--- a/lib/spack/spack/compilers/xl.py
+++ b/lib/spack/spack/compilers/xl.py
@@ -29,17 +29,16 @@ from spack.version import ver
 
 class Xl(Compiler):
     # Subclasses use possible names of C compiler
-    cc_names = ['xlc', 'xlc_r']
+    cc_names = ['xlc']
 
     # Subclasses use possible names of C++ compiler
-    cxx_names = ['xlC', 'xlC_r', 'xlc++', 'xlc++_r']
+    cxx_names = ['xlC', 'xlc++']
 
     # Subclasses use possible names of Fortran 77 compiler
-    f77_names = ['xlf', 'xlf_r']
+    f77_names = ['xlf']
 
     # Subclasses use possible names of Fortran 90 compiler
-    fc_names = ['xlf90', 'xlf90_r', 'xlf95', 'xlf95_r',
-                'xlf2003', 'xlf2003_r', 'xlf2008', 'xlf2008_r']
+    fc_names = ['xlf90', 'xlf95', 'xlf2003', 'xlf2008']
 
     # Named wrapper links within spack.build_env_path
     link_paths = {'cc': 'xl/xlc',
@@ -62,6 +61,20 @@ class Xl(Compiler):
     def pic_flag(self):
         return "-qpic"
 
+    @property
+    def fflags(self):
+        # The -qzerosize flag is effective only for the Fortran 77
+        # compilers and allows the use of zero size objects.
+        # For Fortran 90 and beyond, it is set by default and has not impact.
+        # Its use has no negative side effects.
+        # The -qstrict flag allows the Fortran 90+ compilers to parse the
+        # source files using fixed form rule. As a result, if -qfixed is in
+        # effect, free form files (that are not also fixed form files) will
+        # fail to compile regardless of the compiler invocation command.
+        # Use the -qfree flag in the packages' configuration file to undo the
+        #  -qfixed flag, as the last one wins.
+        return "-qzerosize -qfixed"
+
     @classmethod
     def default_version(cls, comp):
         """The '-qversion' is the standard option fo XL compilers.
diff --git a/lib/spack/spack/compilers/xl_r.py b/lib/spack/spack/compilers/xl_r.py
new file mode 100644
index 0000000000..ca76f219ce
--- /dev/null
+++ b/lib/spack/spack/compilers/xl_r.py
@@ -0,0 +1,128 @@
+##############################################################################
+# Copyright (c) 2016, International Business Machines Corporation
+#
+# This file is part of Spack.
+# Created by Serban Maerean, serban@us.ibm.com based on a similar file,
+# spack/lib/spack/spack/compilers/xl.py, produced 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.compiler import *
+import llnl.util.tty as tty
+from spack.version import ver
+
+
+class XlR(Compiler):
+    # Subclasses use possible names of C compiler
+    cc_names = ['xlc_r']
+
+    # Subclasses use possible names of C++ compiler
+    cxx_names = ['xlC_r', 'xlc++_r']
+
+    # Subclasses use possible names of Fortran 77 compiler
+    f77_names = ['xlf_r']
+
+    # Subclasses use possible names of Fortran 90 compiler
+    fc_names = ['xlf90_r', 'xlf95_r', 'xlf2003_r', 'xlf2008_r']
+
+    # Named wrapper links within spack.build_env_path
+    link_paths = {'cc': 'xl_r/xlc_r',
+                  'cxx': 'xl_r/xlc++_r',
+                  'f77': 'xl_r/xlf_r',
+                  'fc': 'xl_r/xlf90_r'}
+
+    @property
+    def openmp_flag(self):
+        return "-qsmp=omp"
+
+    @property
+    def cxx11_flag(self):
+        if self.version < ver('13.1'):
+            tty.die("Only xlC 13.1 and above have some c++11 support.")
+        else:
+            return "-qlanglvl=extended0x"
+
+    @property
+    def pic_flag(self):
+        return("-qpic")
+
+    @property
+    def fflags(self):
+        # The -qzerosize flag is effective only for the Fortran 77
+        # compilers and allows the use of zero size objects.
+        # For Fortran 90 and beyond, it is set by default and has not impact.
+        # Its use has no negative side effects.
+        # The -qstrict flag allows the Fortran 90+ compilers to parse the
+        # source files using fixed form rule. As a result, if -qfixed is in
+        # effect, free form files (that are not also fixed form files) will
+        # fail to compile regardless of the compiler invocation command.
+        # Use the -qfree flag in the packages' configuration file to undo the
+        #  -qfixed flag, as the last one wins.
+        return "-qzerosize -qfixed"
+
+    @classmethod
+    def default_version(self, comp):
+        """The '-qversion' is the standard option fo XL compilers.
+           Output looks like this::
+
+              IBM XL C/C++ for Linux, V11.1 (5724-X14)
+              Version: 11.01.0000.0000
+
+           or::
+
+              IBM XL Fortran for Linux, V13.1 (5724-X16)
+              Version: 13.01.0000.0000
+
+           or::
+
+              IBM XL C/C++ for AIX, V11.1 (5724-X13)
+              Version: 11.01.0000.0009
+
+           or::
+
+              IBM XL C/C++ Advanced Edition for Blue Gene/P, V9.0
+              Version: 09.00.0000.0017
+        """
+
+        return get_compiler_version(
+            comp, '-qversion', r'([0-9]?[0-9]\.[0-9])')
+
+    @classmethod
+    def fc_version(cls, fc):
+        """The fortran and C/C++ versions of the XL compiler are always
+           two units apart.  By this we mean that the fortran release that
+           goes with XL C/C++ 11.1 is 13.1.  Having such a difference in
+           version number is confusing spack quite a lot.  Most notably
+           if you keep the versions as is the default xl compiler will
+           only have fortran and no C/C++.  So we associate the Fortran
+           compiler with the version associated to the C/C++ compiler.
+           One last stumble. Version numbers over 10 have at least a .1
+           those under 10 a .0. There is no xlf 9.x or under currently
+           available. BG/P and BG/L can such a compiler mix and possibly
+           older version of AIX and linux on power.
+        """
+        fver = get_compiler_version(fc, '-qversion', r'([0-9]?[0-9]\.[0-9])')
+        cver = float(fver) - 2
+        if cver < 10:
+            cver = cver - 0.1
+        return str(cver)
+
+    @classmethod
+    def f77_version(cls, f77):
+        return cls.fc_version(f77)