1 files changed, 122 insertions, 0 deletions
diff --git a/frontends/ilang/lexer.l b/frontends/ilang/lexer.l
new file mode 100644
index 00000000..e331c267
--- /dev/null
+++ b/frontends/ilang/lexer.l
@@ -0,0 +1,122 @@
+/*
+ *  yosys -- Yosys Open SYnthesis Suite
+ *
+ *  Copyright (C) 2012  Clifford Wolf <clifford@clifford.at>
+ *  
+ *  Permission to use, copy, modify, and/or distribute this software for any
+ *  purpose with or without fee is hereby granted, provided that the above
+ *  copyright notice and this permission notice appear in all copies.
+ *  
+ *  THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ *  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ *  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ *  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ *  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ *  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ *  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ *  ---
+ *
+ *  A very simple and straightforward frontend for the RTLIL text
+ *  representation (as generated by the 'ilang' backend).
+ *
+ */
+
+%{
+#include "kernel/rtlil.h"
+#include "parser.tab.h"
+%}
+
+%option yylineno
+%option noyywrap
+%option nounput
+%option prefix="rtlil_frontend_ilang_yy"
+
+%x STRING
+
+%%
+
+"module"	{ return TOK_MODULE; }
+"attribute"	{ return TOK_ATTRIBUTE; }
+"parameter"	{ return TOK_PARAMETER; }
+"wire"		{ return TOK_WIRE; }
+"memory"	{ return TOK_MEMORY; }
+"auto"		{ return TOK_AUTO; }
+"width"		{ return TOK_WIDTH; }
+"offset"	{ return TOK_OFFSET; }
+"size"		{ return TOK_SIZE; }
+"input"		{ return TOK_INPUT; }
+"output"	{ return TOK_OUTPUT; }
+"inout"		{ return TOK_INOUT; }
+"cell"		{ return TOK_CELL; }
+"connect"	{ return TOK_CONNECT; }
+"switch"	{ return TOK_SWITCH; }
+"case"		{ return TOK_CASE; }
+"assign"	{ return TOK_ASSIGN; }
+"sync"		{ return TOK_SYNC; }
+"low"		{ return TOK_LOW; }
+"high"		{ return TOK_HIGH; }
+"posedge"	{ return TOK_POSEDGE; }
+"negedge"	{ return TOK_NEGEDGE; }
+"edge"		{ return TOK_EDGE; }
+"always"	{ return TOK_ALWAYS; }
+"update"	{ return TOK_UPDATE; }
+"process"	{ return TOK_PROCESS; }
+"end"		{ return TOK_END; }
+
+[a-z]+		{ return TOK_INVALID; }
+
+"\\"[^ \t\r\n]+		{ rtlil_frontend_ilang_yylval.string = strdup(yytext); return TOK_ID; }
+"$"[^ \t\r\n]+		{ rtlil_frontend_ilang_yylval.string = strdup(yytext); return TOK_ID; }
+"."[0-9]+		{ rtlil_frontend_ilang_yylval.string = strdup(yytext); return TOK_ID; }
+
+[0-9]+'[01xzm-]+	{ rtlil_frontend_ilang_yylval.string = strdup(yytext); return TOK_VALUE; }
+[0-9]+			{ rtlil_frontend_ilang_yylval.integer = atoi(yytext); return TOK_INT; }
+
+\"		{ BEGIN(STRING); }
+<STRING>\\.	{ yymore(); }
+<STRING>\"	{
+	BEGIN(0);
+	char *yystr = strdup(yytext);
+	yystr[strlen(yytext) - 1] = 0;
+	int i = 0, j = 0;
+	while (yystr[i]) {
+		if (yystr[i] == '\\' && yystr[i + 1]) {
+			i++;
+			if (yystr[i] == 'n')
+				yystr[i] = '\n';
+			else if (yystr[i] == 't')
+				yystr[i] = '\t';
+			else if ('0' <= yystr[i] && yystr[i] <= '7') {
+				yystr[i] = yystr[i] - '0';
+				if ('0' <= yystr[i + 1] && yystr[i + 1] <= '7') {
+					yystr[i + 1] = yystr[i] * 8 + yystr[i + 1] - '0';
+					i++;
+				}
+				if ('0' <= yystr[i + 1] && yystr[i + 1] <= '7') {
+					yystr[i + 1] = yystr[i] * 8 + yystr[i + 1] - '0';
+					i++;
+				}
+			}
+		}
+		yystr[j++] = yystr[i++];
+	}
+	yystr[j] = 0;
+	rtlil_frontend_ilang_yylval.string = yystr;
+	return TOK_STRING;
+}
+<STRING>.	{ yymore(); }
+
+"#"[^\n]*\n	/* ignore comments */
+[ \t]		/* ignore non-newline whitespaces */
+[\r\n]+		{ return TOK_EOL; }
+
+.               { return *yytext; }
+
+%%
+
+// this is a hack to avoid the 'yyinput defined but not used' error msgs
+void *rtlil_frontend_ilang_avoid_input_warnings() {
+	return (void*)&yyinput;
+}
+