[GSoC][match-and-simplify] sanitize option checking

[Prathamesh Kulkarni]

Added checks to see if either cmmand-line options is not repeated,
and generates match-and-simplify code on both GENERIC and GIMPLE
if both -generic and -gimple are specified.

* genmatch.c (cmd_options): New struct.
    (check_repeated_arg): New function.
    (parse_cmd_arg): Likewise.
    (main): Emit diagnostic if no command line options are given.
               Add call to parse_cmd_arg.

Thanks,
Prathamesh

Index: genmatch.c
===================================================================
--- genmatch.c	(revision 212928)
+++ genmatch.c	(working copy)
@@ -2118,6 +2118,34 @@ parse_pattern (cpp_reader *r, vec<simpli
   eat_token (r, CPP_CLOSE_PAREN);
 }
 
+struct cmd_options
+{
+  bool generic;
+  bool gimple;
+  bool verbose;
+
+  cmd_options (): generic (false), gimple (false), verbose (false) {}
+};
+
+void
+check_repeated_arg (const char *arg, const char *expected_arg, bool& option) 
+{
+  if (strcmp (arg, expected_arg) == 0)
+    {
+      if (option)
+	fatal ("%s repeated", arg);
+      option = true;
+    }
+}
+
+void
+parse_cmd_arg (const char *arg, cmd_options& opt)
+{
+  check_repeated_arg (arg, "-gimple", opt.gimple);
+  check_repeated_arg (arg, "-generic", opt.generic);
+  check_repeated_arg (arg, "-v", opt.verbose); 
+}
+
 int
 main(int argc, char **argv)
 {
@@ -2126,25 +2154,12 @@ main(int argc, char **argv)
   progname = "genmatch";
 
   if (argc < 2)
-    return 1;
+    fatal ("pd file not specified"); 
 
-  bool gimple = true;
-  bool verbose = false;
+  cmd_options opt;
   char *input = argv[argc-1];
   for (int i = 1; i < argc - 1; ++i)
-    {
-      if (strcmp (argv[i], "-gimple") == 0)
-	gimple = true;
-      else if (strcmp (argv[i], "-generic") == 0)
-	gimple = false;
-      else if (strcmp (argv[i], "-v") == 0)
-	verbose = true;
-      else
-	{
-	  fprintf (stderr, "Usage: genmatch [-gimple] [-generic] [-v] input\n");
-	  return 1;
-	}
-    }
+    parse_cmd_arg (argv[i], opt);
 
   line_table = XCNEW (struct line_maps);
   linemap_init (line_table);
@@ -2157,7 +2172,7 @@ main(int argc, char **argv)
 
   if (!cpp_read_main_file (r, input))
     return 1;
-  cpp_define (r, gimple ? "GIMPLE=1": "GENERIC=1");
+  cpp_define (r, opt.gimple ? "GIMPLE=1": "GENERIC=1");
 
   /* Pre-seed operators.  */
   operators.create (1024);
@@ -2188,7 +2203,7 @@ main(int argc, char **argv)
   for (unsigned i = 0; i < simplifiers.length (); ++i)
     lower_commutative (simplifiers[i], out_simplifiers);
 
-  if (verbose)
+  if (opt.verbose)
     for (unsigned i = 0; i < out_simplifiers.length (); ++i)
       print_matches (out_simplifiers[i]);
 
@@ -2196,15 +2211,16 @@ main(int argc, char **argv)
   for (unsigned i = 0; i < out_simplifiers.length (); ++i)
     dt.insert (out_simplifiers[i], i);
 
-  if (verbose)
+  if (opt.verbose)
     dt.print (stderr);
 
-  if (gimple)
+  if (opt.gimple)
     {
       write_header (stdout, out_simplifiers, "gimple-match-head.c");
       dt.gen_gimple (stdout);
     }
-  else
+
+  if (opt.generic)
     {
       write_header (stdout, out_simplifiers, "generic-match-head.c");
       dt.gen_generic (stdout);