1 files changed, 114 insertions, 0 deletions
diff --git a/tools/perf/util/expr.l b/tools/perf/util/expr.l
new file mode 100644
index 000000000000..eaad29243c23
--- /dev/null
+++ b/tools/perf/util/expr.l
@@ -0,0 +1,114 @@
+%option prefix="expr_"
+%option reentrant
+%option bison-bridge
+
+%{
+#include <linux/compiler.h>
+#include "expr.h"
+#include "expr-bison.h"
+
+char *expr_get_text(yyscan_t yyscanner);
+YYSTYPE *expr_get_lval(yyscan_t yyscanner);
+
+static int __value(YYSTYPE *yylval, char *str, int base, int token)
+{
+	u64 num;
+
+	errno = 0;
+	num = strtoull(str, NULL, base);
+	if (errno)
+		return EXPR_ERROR;
+
+	yylval->num = num;
+	return token;
+}
+
+static int value(yyscan_t scanner, int base)
+{
+	YYSTYPE *yylval = expr_get_lval(scanner);
+	char *text = expr_get_text(scanner);
+
+	return __value(yylval, text, base, NUMBER);
+}
+
+/*
+ * Allow @ instead of / to be able to specify pmu/event/ without
+ * conflicts with normal division.
+ */
+static char *normalize(char *str)
+{
+	char *ret = str;
+	char *dst = str;
+
+	while (*str) {
+		if (*str == '@')
+			*dst++ = '/';
+		else if (*str == '\\')
+			*dst++ = *++str;
+		else
+			*dst++ = *str;
+		str++;
+	}
+
+	*dst = 0x0;
+	return ret;
+}
+
+static int str(yyscan_t scanner, int token)
+{
+	YYSTYPE *yylval = expr_get_lval(scanner);
+	char *text = expr_get_text(scanner);
+
+	yylval->str = normalize(strdup(text));
+	if (!yylval->str)
+		return EXPR_ERROR;
+
+	yylval->str = normalize(yylval->str);
+	return token;
+}
+%}
+
+number		[0-9]+
+
+sch		[-,=]
+spec		\\{sch}
+sym		[0-9a-zA-Z_\.:@]+
+symbol		{spec}*{sym}*{spec}*{sym}*
+
+%%
+	{
+		int start_token;
+
+		start_token = expr_get_extra(yyscanner);
+
+		if (start_token) {
+			expr_set_extra(NULL, yyscanner);
+			return start_token;
+		}
+	}
+
+max		{ return MAX; }
+min		{ return MIN; }
+if		{ return IF; }
+else		{ return ELSE; }
+#smt_on		{ return SMT_ON; }
+{number}	{ return value(yyscanner, 10); }
+{symbol}	{ return str(yyscanner, ID); }
+"|"		{ return '|'; }
+"^"		{ return '^'; }
+"&"		{ return '&'; }
+"-"		{ return '-'; }
+"+"		{ return '+'; }
+"*"		{ return '*'; }
+"/"		{ return '/'; }
+"%"		{ return '%'; }
+"("		{ return '('; }
+")"		{ return ')'; }
+","		{ return ','; }
+.		{ }
+%%
+
+int expr_wrap(void *scanner __maybe_unused)
+{
+	return 1;
+}