Add the PARSE_ARGUMENTS CMake macro to LLVM so I can use it to clean

up add_clang_unittest's calling convention.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126031 91177308-0d34-0410-b5e6-96231b3b80d8

cmake/modules/LLVMParseArguments.cmake

@@ -0,0 +1,80 @@
+# Copied from http://www.itk.org/Wiki/CMakeMacroParseArguments under
+# http://creativecommons.org/licenses/by/2.5/.
+#
+# The PARSE_ARGUMENTS macro will take the arguments of another macro and define
+# several variables. The first argument to PARSE_ARGUMENTS is a prefix to put on
+# all variables it creates. The second argument is a list of names, and the
+# third argument is a list of options. Both of these lists should be quoted. The
+# rest of PARSE_ARGUMENTS are arguments from another macro to be parsed.
+#
+# PARSE_ARGUMENTS(prefix arg_names options arg1 arg2...)
+#
+# For each item in options, PARSE_ARGUMENTS will create a variable with that
+# name, prefixed with prefix_. So, for example, if prefix is MY_MACRO and
+# options is OPTION1;OPTION2, then PARSE_ARGUMENTS will create the variables
+# MY_MACRO_OPTION1 and MY_MACRO_OPTION2. These variables will be set to true if
+# the option exists in the command line or false otherwise.
+#
+#For each item in arg_names, PARSE_ARGUMENTS will create a variable with that
+#name, prefixed with prefix_. Each variable will be filled with the arguments
+#that occur after the given arg_name is encountered up to the next arg_name or
+#the end of the arguments. All options are removed from these
+#lists. PARSE_ARGUMENTS also creates a prefix_DEFAULT_ARGS variable containing
+#the list of all arguments up to the first arg_name encountered.
+#
+#Here is a simple, albeit impractical, example of using PARSE_ARGUMENTS that
+#demonstrates its behavior.
+#
+# SET(arguments
+#     hello OPTION3 world
+#     LIST3 foo bar
+#     OPTION2
+#     LIST1 fuz baz
+#     )
+#
+# PARSE_ARGUMENTS(ARG "LIST1;LIST2;LIST3" "OPTION1;OPTION2;OPTION3" ${arguments})
+#
+# PARSE_ARGUMENTS creates 7 variables and sets them as follows:
+#   ARG_DEFAULT_ARGS: hello;world
+#   ARG_LIST1: fuz;baz
+#   ARG_LIST2:
+#   ARG_LIST3: foo;bar
+#   ARG_OPTION1: FALSE
+#   ARG_OPTION2: TRUE
+#   ARG_OPTION3: TRUE
+#
+# If you don't have any options, use an empty string in its place.
+#   PARSE_ARGUMENTS(ARG "LIST1;LIST2;LIST3" "" ${arguments})
+# Likewise if you have no lists.
+#   PARSE_ARGUMENTS(ARG "" "OPTION1;OPTION2;OPTION3" ${arguments})
+
+MACRO(PARSE_ARGUMENTS prefix arg_names option_names)
+  SET(DEFAULT_ARGS)
+  FOREACH(arg_name ${arg_names})
+    SET(${prefix}_${arg_name})
+  ENDFOREACH(arg_name)
+  FOREACH(option ${option_names})
+    SET(${prefix}_${option} FALSE)
+  ENDFOREACH(option)
+
+  SET(current_arg_name DEFAULT_ARGS)
+  SET(current_arg_list)
+  FOREACH(arg ${ARGN})
+    SET(larg_names ${arg_names})
+    LIST(FIND larg_names "${arg}" is_arg_name)
+    IF (is_arg_name GREATER -1)
+      SET(${prefix}_${current_arg_name} ${current_arg_list})
+      SET(current_arg_name ${arg})
+      SET(current_arg_list)
+    ELSE (is_arg_name GREATER -1)
+      SET(loption_names ${option_names})
+      LIST(FIND loption_names "${arg}" is_option)
+      IF (is_option GREATER -1)
+        SET(${prefix}_${arg} TRUE)
+      ELSE (is_option GREATER -1)
+        SET(current_arg_list ${current_arg_list} ${arg})
+      ENDIF (is_option GREATER -1)
+    ENDIF (is_arg_name GREATER -1)
+  ENDFOREACH(arg)
+  SET(${prefix}_${current_arg_name} ${current_arg_list})
+ENDMACRO(PARSE_ARGUMENTS)