perf expr: Allow numbers to be followed by a dot

Metrics like UNC_M_POWER_SELF_REFRESH encode 100 as "100." and
consequently the 100 is treated as a symbol. Alter the regular
expression to allow the dot to be before or after the number.

Note, this passed the pmu-events test as that tests the validity of a
number using strtod rather than lex code. strtod allows the dot after.

Add a test for this behavior.

Fixes: 26226a97724d (perf expr: Move expr lexer to flex)
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: John Garry <john.garry@huawei.com>
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: Stephane Eranian <eranian@google.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/tests/expr.c b/tools/perf/tests/expr.c
index 13350c5..1cb02ca 100644 (file)
--- a/tools/perf/tests/expr.c
+++ b/tools/perf/tests/expr.c
@@ -38,6 +38,7 @@ int test__expr(struct test *t __maybe_unused, int subtest __maybe_unused)
        ret |= test(&ctx, "max(1,2) + 1", 3);
        ret |= test(&ctx, "1+1 if 3*4 else 0", 2);
        ret |= test(&ctx, "1.1 + 2.1", 3.2);
+       ret |= test(&ctx, ".1 + 2.", 2.1);
 
        if (ret)
                return ret;

diff --git a/tools/perf/util/expr.l b/tools/perf/util/expr.l
index ceab11b..f397bf8 100644 (file)
--- a/tools/perf/util/expr.l
+++ b/tools/perf/util/expr.l
@@ -81,7 +81,7 @@ static int str(yyscan_t scanner, int token, int runtime)
 }
 %}
 
-number         [0-9]*\.?[0-9]+
+number         ([0-9]+\.?[0-9]*|[0-9]*\.?[0-9]+)
 
 sch            [-,=]
 spec           \\{sch}