scons: Update enum output when not using python

This changeset brings the enum_cc.py file in line with how the
sim_object_param_struct_cc.py file works and updates the SConscript to
correctly tag the created source files.

Change-Id: I4635a4f46de7d62a6c38e71ace121c06e139d486
Signed-off-by: Jason Lowe-Power <jason@lowepower.com>
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/59609
Reviewed-by: Bobby Bruce <bbruce@ucdavis.edu>
Tested-by: kokoro <noreply+kokoro@google.com>
Maintainer: Bobby Bruce <bbruce@ucdavis.edu>

build_tools/enum_cc.py

@@ -48,11 +48,20 @@ from code_formatter import code_formatter
 parser = argparse.ArgumentParser()
 parser.add_argument('modpath', help='module the enum belongs to')
 parser.add_argument('enum_cc', help='enum cc file to generate')
-parser.add_argument('--use-python', action="store_true",
+parser.add_argument('use_python',
-        help='python is enabled in gem5')
+        help='whether python is enabled in gem5 (True or False)')
 
 args = parser.parse_args()
 
+use_python = args.use_python.lower()
+if use_python == 'true':
+    use_python = True
+elif use_python == 'false':
+    use_python = False
+else:
+    print(f'Unrecognized "use_python" value {use_python}', file=sys.stderr)
+    sys.exit(1)
+
 basename = os.path.basename(args.enum_cc)
 enum_name = os.path.splitext(basename)[0]
 
@@ -103,16 +112,13 @@ if not enum.wrapper_is_struct and not enum.is_class:
 code('} // namespace gem5')
 
 
-if not args.use_python:
+if use_python:
-    code.write(args.enum_cc)
-    exit(0)
 
+    name = enum.__name__
+    enum_name = enum.__name__ if enum.enum_name is None else enum.enum_name
+    wrapper_name = enum_name if enum.is_class else enum.wrapper_name
 
-name = enum.__name__
+    code('''#include "pybind11/pybind11.h"
-enum_name = enum.__name__ if enum.enum_name is None else enum.enum_name
-wrapper_name = enum_name if enum.is_class else enum.wrapper_name
-
-code('''#include "pybind11/pybind11.h"
 #include "pybind11/stl.h"
 
 #include <sim/init.hh>
@@ -128,27 +134,27 @@ module_init(py::module_ &m_internal)
     py::module_ m = m_internal.def_submodule("enum_${name}");
 
 ''')
-if enum.is_class:
+    if enum.is_class:
-    code('py::enum_<${enum_name}>(m, "enum_${name}")')
+        code('py::enum_<${enum_name}>(m, "enum_${name}")')
-else:
+    else:
-    code('py::enum_<${wrapper_name}::${enum_name}>(m, "enum_${name}")')
+        code('py::enum_<${wrapper_name}::${enum_name}>(m, "enum_${name}")')
 
-code.indent()
+    code.indent()
-code.indent()
+    code.indent()
-for val in enum.vals:
+    for val in enum.vals:
-    code('.value("${val}", ${wrapper_name}::${val})')
+        code('.value("${val}", ${wrapper_name}::${val})')
-code('.value("Num_${name}", ${wrapper_name}::Num_${enum_name})')
+    code('.value("Num_${name}", ${wrapper_name}::Num_${enum_name})')
-if not enum.is_class:
+    if not enum.is_class:
-    code('.export_values()')
+        code('.export_values()')
-code(';')
+    code(';')
-code.dedent()
+    code.dedent()
 
-code('}')
+    code('}')
-code.dedent()
+    code.dedent()
-code('''
+    code('''
 static EmbeddedPyBind embed_enum("enum_${name}", module_init);
 
 } // namespace gem5
-''')
+    ''')
 
 code.write(args.enum_cc)

src/SConscript

@@ -186,7 +186,8 @@ class SimObject(PySource):
                     SIMOBJ=simobj,
                     PARAMS_CC=cc_file,
                     USE_PYTHON=env['USE_PYTHON'])
-            Source(cc_file, tags=self.tags, add_tags='python')
+            Source(cc_file, tags=self.tags,
+                   add_tags=('python' if env['USE_PYTHON'] else None))
 
             # CXX config header.
             gem5py_env.Command([ "${CXXCONFIG_HH}" ], srcs,
@@ -230,8 +231,9 @@ class SimObject(PySource):
                     ENUM=enum,
                     ENUM_CC=cc_file,
                     ENUMCC_PY=build_tools.File('enum_cc.py'),
-                    USE_PYTHON='--use-python' if env['USE_PYTHON'] else '')
+                    USE_PYTHON=env['USE_PYTHON'])
-            Source(cc_file, tags=self.tags, add_tags='python')
+            Source(cc_file, tags=self.tags,
+                   add_tags=('python' if env['USE_PYTHON'] else None))
 
 # This regular expression is simplistic and assumes that the import takes up
 # the entire line, doesn't have the keyword "public", uses double quotes, has