Revert mangling of names with -fprofile-generate=<dir>.

	PR gcov-profile/91971
	PR gcov-profile/93466
	* coverage.c (coverage_init): Revert mangling of
	path into filename.  It can lead to huge filename length.
	Creation of subfolders seem more natural.

gcc/ChangeLog

+2020-02-06  Martin Liska  <mliska@suse.cz>
+
+	PR gcov-profile/91971
+	PR gcov-profile/93466
+	* coverage.c (coverage_init): Revert mangling of
+	path into filename.  It can lead to huge filename length.
+	Creation of subfolders seem more natural.
+
 2020-02-06  Stam Markianos-Wright  <stam.markianos-wright@arm.com>
 
 	PR target/93300

gcc/coverage.c

@@ -1227,14 +1227,6 @@ coverage_init (const char *filename)
       else
 	profile_data_prefix = getpwd ();
     }
-  else if (profile_data_prefix != NULL)
-    {
-      /* when filename is a absolute path, we also need to mangle the full
-      path of filename to prevent the profiling data being stored into a
-      different path than that specified by profile_data_prefix.  */
-      filename = mangle_path (filename);
-      len = strlen (filename);
-    }
 
   if (profile_data_prefix)
     prefix_len = strlen (profile_data_prefix);