perf annotate browser: Add visual cue for retq instruction

Just use a left arrow prefixing retqs.

Requested-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/n/tip-tnpfijuomrntbnl5vr6ibdwa@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/ui/browsers/annotate.c

@@ -127,11 +127,20 @@ static void annotate_browser__write(struct ui_browser *self, void *entry, int ro
 
 			dl->ins->ops->scnprintf(dl->ins, bf, sizeof(bf), &dl->ops,
 						!ab->use_offset);
-			printed += 2;
-		} else
-			scnprintf(bf, sizeof(bf), "  %-6.6s %s", dl->name, dl->ops.raw);
+		} else {
+			if (strcmp(dl->name, "retq")) {
+				slsmg_write_nstring(" ", 2);
+			} else {
+				SLsmg_set_char_set(1);
+				SLsmg_write_char(SLSMG_LARROW_CHAR);
+				SLsmg_set_char_set(0);
+				SLsmg_write_char(' ');
+			}
+
+			scnprintf(bf, sizeof(bf), "%-6.6s %s", dl->name, dl->ops.raw);
+		}
 
-		slsmg_write_nstring(bf, width - 10 - printed);
+		slsmg_write_nstring(bf, width - 12 - printed);
 	}
 
 	if (current_entry)