Initial revision

lang/cem/cemcom.ansi/label.c

@@ -0,0 +1,74 @@
+/*
+ * (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
+ * See the copyright notice in the ACK home directory, in the file "Copyright".
+ */
+/* $Header$ */
+/*		L A B E L   H A N D L I N G		*/
+
+#include	"Lpars.h"
+#include	"level.h"
+#include	"idf.h"
+#include	"label.h"
+#include	"arith.h"
+#include	"def.h"
+#include	"type.h"
+#include	"noRoption.h"
+
+extern char options[];
+
+enter_label(idf, defining)
+	register struct idf *idf;
+{
+	/*	The identifier idf is entered as a label. If it is new,
+		it is entered into the idf list with the largest possible
+		scope, i.e., on the lowest possible level.
+		If defining, the label comes from a label statement.
+	*/
+	if (idf->id_def)	{
+		register struct def *def = idf->id_def;
+		
+		if (def->df_sc == LABEL)	{
+			if (defining && def->df_initialized)
+				error("redeclaration of label %s",
+								idf->id_text);
+		}
+		else	{		/* there may still be room for it */
+#ifndef NOROPTION
+			if (options['R'] && def->df_sc == TYPEDEF)
+				warning("label %s is also a typedef",
+					idf->id_text);
+#endif
+			
+			if (def->df_level == level)	/* but alas, no */
+				error("%s is not a label", idf->id_text);
+			else	{
+				register int lvl = def->df_level + 1;
+				
+#ifndef NOROPTION
+				if (options['R'] && def->df_level > L_LOCAL)
+					warning("label %s is not function-wide",
+								idf->id_text);
+#endif
+				if (lvl < L_LOCAL)
+					lvl = L_LOCAL;
+				add_def(idf, LABEL, label_type, lvl);
+			}
+		}
+	}
+	else	{
+		add_def(idf, LABEL, label_type, L_LOCAL);
+	}
+	if (idf->id_def->df_address == 0)
+		idf->id_def->df_address = (arith) text_label();
+	if (defining)
+		idf->id_def->df_initialized = 1;
+}
+
+unstack_label(idf)
+	register struct idf *idf;
+{
+	/*	The scope in which the label idf occurred is left.
+	*/
+	if (!idf->id_def->df_initialized && !is_anon_idf(idf))
+		error("label %s not defined", idf->id_text);
+}