perf annotate: Handle ins parsing failures

Don't use the ins's ->sncprintf() if the parsing failed.

For example, this fixes the display of "imul %edx".  Without this patch:

       |      imul   (null),(null)

After this patch:

       |      imul   %edx

Signed-off-by: Rabin Vincent <rabin@rab.in>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1421607621-15005-1-git-send-email-rabin@rab.in
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/util/annotate.c

@@ -183,8 +183,9 @@ static int lock__parse(struct ins_operands *ops)
 	if (!ops->locked.ins->ops)
 		return 0;
 
-	if (ops->locked.ins->ops->parse)
-		ops->locked.ins->ops->parse(ops->locked.ops);
+	if (ops->locked.ins->ops->parse &&
+	    ops->locked.ins->ops->parse(ops->locked.ops) < 0)
+		goto out_free_ops;
 
 	return 0;
 
@@ -531,8 +532,8 @@ static void disasm_line__init_ins(struct disasm_line *dl)
 	if (!dl->ins->ops)
 		return;
 
-	if (dl->ins->ops->parse)
-		dl->ins->ops->parse(&dl->ops);
+	if (dl->ins->ops->parse && dl->ins->ops->parse(&dl->ops) < 0)
+		dl->ins = NULL;
 }
 
 static int disasm_line__parse(char *line, char **namep, char **rawp)