perf expr: Parse numbers as doubles

This is expected in expr.y and metrics use floating point values such as
x86 broadwell IFetch_Line_Utilization.

Fixes: 26226a9772 (perf expr: Move expr lexer to flex)
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Kajol Jain <kjain@linux.ibm.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Haiyan Song <haiyanx.song@intel.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: John Garry <john.garry@huawei.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Clarke <pc@us.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200501173333.227162-7-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/expr.l

@@ -10,12 +10,12 @@
 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)
+static double __value(YYSTYPE *yylval, char *str, int token)
 {
-	u64 num;
+	double num;
 
 	errno = 0;
-	num = strtoull(str, NULL, base);
+	num = strtod(str, NULL);
 	if (errno)
 		return EXPR_ERROR;
 
@@ -23,12 +23,12 @@ static int __value(YYSTYPE *yylval, char *str, int base, int token)
 	return token;
 }
 
-static int value(yyscan_t scanner, int base)
+static int value(yyscan_t scanner)
 {
 	YYSTYPE *yylval = expr_get_lval(scanner);
 	char *text = expr_get_text(scanner);
 
-	return __value(yylval, text, base, NUMBER);
+	return __value(yylval, text, NUMBER);
 }
 
 /*
@@ -81,7 +81,7 @@ static int str(yyscan_t scanner, int token, int runtime)
 }
 %}
 
-number		[0-9]+
+number		[0-9]*\.?[0-9]+
 
 sch		[-,=]
 spec		\\{sch}
@@ -105,7 +105,7 @@ min		{ return MIN; }
 if		{ return IF; }
 else		{ return ELSE; }
 #smt_on		{ return SMT_ON; }
-{number}	{ return value(yyscanner, 10); }
+{number}	{ return value(yyscanner); }
 {symbol}	{ return str(yyscanner, ID, sctx->runtime); }
 "|"		{ return '|'; }
 "^"		{ return '^'; }