perf tools: Add OCaml demangling

Detect symbols generated by the OCaml compiler based on their prefix.

Demangle OCaml symbols, returning a newly allocated string (like the
existing Java demangling functionality).

Move a helper function (hex) from tests/code-reading.c to util/string.c

To test:

  echo 'Printf.printf "%d\n" (Random.int 42)' > test.ml
  perf record ocamlopt.opt test.ml
  perf report -d ocamlopt.opt

Signed-off-by: Fabian Hemmer <copy@copy.sh>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LPU-Reference: 20210203211537.b25ytjb6dq5jfbwx@nyu
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 1 insertions, 9 deletions

diff --git a/tools/perf/tests/code-reading.c b/tools/perf/tests/code-reading.c
index 7c098d49c77e..280f0348a09c 100644
--- a/tools/perf/tests/code-reading.c
+++ b/tools/perf/tests/code-reading.c
@@ -26,6 +26,7 @@
 #include "event.h"
 #include "record.h"
 #include "util/mmap.h"
+#include "util/string2.h"
 #include "util/synthetic-events.h"
 #include "thread.h"
 
@@ -41,15 +42,6 @@ struct state {
 	size_t done_cnt;
 };
 
-static unsigned int hex(char c)
-{
-	if (c >= '0' && c <= '9')
-		return c - '0';
-	if (c >= 'a' && c <= 'f')
-		return c - 'a' + 10;
-	return c - 'A' + 10;
-}
-
 static size_t read_objdump_chunk(const char **line, unsigned char **buf,
 				 size_t *buf_len)
 {