RFA: some minor tweaks to the options scripts

[Richard Sandiford <rsandifo at redhat dot com>]

I'm about to submit a patch to add a new options flag, "MaskExists".
While writing that patch, I noticed a difference between the way
opt-functions.awk and opt[hc]-gen.awk check for flags: the former
carefully checks for word boundaries but the latter don't.

It's hardly a big deal or anything, and it certainly doesn't cause
problems at the moment.  On the other hand, I guess each new flag
increases the likelihood of a substring match triggering unexpectedly,
so while adding this new flag, I thought I might as well add a new
function for wrapping up the stricter check performed by
opt-functions.awk.

Making this change led to some overly-long lines in the way we
built up the CL_* mask.  Rather than split the lines up, it seemed
more readable to rework it to use a single assignment and helper
function instead.

The patch also makes the Init(...) handling use the recently-added
opt_args function.

All in all, it's pretty whimsical stuff, sorry.

Patch bootstrapped & regression tested on i686-pc-linux-gnu.
I also checked that it has no effect on the options.[hc] output
for that target.  OK to install?

Richard


	* opt-functions.awk (flag_set_p, test_flag): New functions.
	(switch_flags): Use them.
	* opth-gen.awk: Use flag_set_p to check for flags.
	* optc-gen.awk: Likewise.  Use opt_args to check for Init(...) flags.

Index: opt-functions.awk
===================================================================
RCS file: /cvs/gcc/gcc/gcc/opt-functions.awk,v
retrieving revision 2.2
diff -u -p -F^\([(a-zA-Z0-9_]\|#define\) -r2.2 opt-functions.awk
--- opt-functions.awk	14 Mar 2005 20:18:38 -0000	2.2
+++ opt-functions.awk	18 Mar 2005 08:59:01 -0000
@@ -18,6 +18,21 @@
 
 # Some common subroutines for use by opt[ch]-gen.awk.
 
+# Return nonzero if FLAGS contains a flag matching REGEX.
+function flag_set_p(regex, flags)
+{
+	return (" " flags " ") ~ (" " regex " ")
+}
+
+# Return STRING if FLAGS contains a flag matching regexp REGEX,
+# otherwise return the empty string.
+function test_flag(regex, flags, string)
+{
+	if (flag_set_p(regex, flags))
+		return string
+	return ""
+}
+
 # If FLAGS contains a "NAME(...argument...)" flag, return the value
 # of the argument.  Return the empty string otherwise.
 function opt_args(name, flags)
@@ -47,24 +62,22 @@ function nth_arg(n, s)
 # Return a bitmask of CL_* values for option flags FLAGS.
 function switch_flags (flags)
 {
-	flags = " " flags " "
 	result = "0"
 	for (j = 0; j < n_langs; j++) {
-		regex = " " langs[j] " "
+		regex = langs[j]
 		gsub ( "\\+", "\\+", regex )
-		if (flags ~ regex)
-			result = result " | " macros[j]
+		result = result test_flag(regex, flags, " | " macros[j])
 	}
-	if (flags ~ " Common ") result = result " | CL_COMMON"
-	if (flags ~ " Target ") result = result " | CL_TARGET"
-	if (flags ~ " Joined ") result = result " | CL_JOINED"
-	if (flags ~ " JoinedOrMissing ") \
-	    result = result " | CL_JOINED | CL_MISSING_OK"
-	if (flags ~ " Separate ") result = result " | CL_SEPARATE"
-	if (flags ~ " RejectNegative ") result = result " | CL_REJECT_NEGATIVE"
-	if (flags ~ " UInteger ") result = result " | CL_UINTEGER"
-	if (flags ~ " Undocumented ") result = result " | CL_UNDOCUMENTED"
-	if (flags ~ " Report ") result = result " | CL_REPORT"
+	result = result \
+	  test_flag("Common", flags, " | CL_COMMON") \
+	  test_flag("Target", flags, " | CL_TARGET") \
+	  test_flag("Joined", flags, " | CL_JOINED") \
+	  test_flag("JoinedOrMissing", flags, " | CL_JOINED | CL_MISSING_OK") \
+	  test_flag("Separate", flags, " | CL_SEPARATE") \
+	  test_flag("RejectNegative", flags, " | CL_REJECT_NEGATIVE") \
+	  test_flag("UInteger", flags, " | CL_UINTEGER") \
+	  test_flag("Undocumented", flags,  " | CL_UNDOCUMENTED") \
+	  test_flag("Report", flags, " | CL_REPORT")
 	sub( "^0 \\| ", "", result )
 	return result
 }
Index: opth-gen.awk
===================================================================
RCS file: /cvs/gcc/gcc/gcc/opth-gen.awk,v
retrieving revision 2.2
diff -u -p -F^\([(a-zA-Z0-9_]\|#define\) -r2.2 opth-gen.awk
--- opth-gen.awk	14 Mar 2005 20:18:38 -0000	2.2
+++ opth-gen.awk	18 Mar 2005 08:59:01 -0000
@@ -127,7 +127,7 @@ for (i = 0; i < n_opts; i++)
 	# a later switch S is a longer prefix of a switch T, T
 	# will be back-chained to S in a later iteration of this
 	# for() loop, which is what we want.
-	if (flags[i] ~ "Joined") {
+	if (flag_set_p("Joined.*", flags[i])) {
 		for (j = i + 1; j < n_opts; j++) {
 			if (substr (opts[j], 1, len) != opts[i])
 				break;
Index: optc-gen.awk
===================================================================
RCS file: /cvs/gcc/gcc/gcc/optc-gen.awk,v
retrieving revision 2.1
diff -u -p -F^\([(a-zA-Z0-9_]\|#define\) -r2.1 optc-gen.awk
--- optc-gen.awk	18 Jun 2004 01:59:45 -0000	2.1
+++ optc-gen.awk	18 Mar 2005 08:59:01 -0000
@@ -63,22 +63,16 @@ for (i = 0; i < n_opts; i++) {
 	if (name == "")
 		continue;
 
-	if (flags[i] ~ "VarExists")
+	if (flag_set_p("VarExists", flags[i]))
 		continue;
 
-	if (flags[i] ~ "Init\\(")
-	    {
-		    init = flags[i];
-		    sub(".*Init\\(","",init);
-		    sub("\\).*","",init);
-		    init = " = " init;
-	    }
-	 else
-		    init = "";
+	init = opt_args("Init", flags[i])
+	if (init != "")
+		init = " = " init;
 
-	 printf ("/* Set by -%s.\n   %s  */\nint %s%s;\n\n",
+	printf ("/* Set by -%s.\n   %s  */\nint %s%s;\n\n",
 	    opts[i], help[i], name,init)
-    }
+}
 
 
 print "const char * const lang_names[] =\n{"
@@ -117,7 +111,7 @@ for (i = 0; i < n_opts; i++)
 		# a later switch S is a longer prefix of a switch T, T
 		# will be back-chained to S in a later iteration of this
 		# for() loop, which is what we want.
-		if (flags[i] ~ "Joined") {
+		if (flag_set_p("Joined.*", flags[i])) {
 			for (j = i + 1; j < n_opts; j++) {
 				if (substr (opts[j], 1, len) != opts[i])
 					break;