[PATCH] ctfc: Free CTF type and CTF variable objects in ctfc_delete_container ()

[Indu Bhagat <indu.bhagat@oracle.com>]

Hello,

This patch fixes an outstanding issue with memory cleanup in the CTF container.
Earlier the two hash tables in the CTF container were not cleaned up in
ctfc_delete_container ().  With this patch, we first free up the CTF type and
CTF variable entries in the hash_table slots, followed by emptying of the hash
tables.

Bootstrapped and regression tested on x86_64.

Thanks

------------------------

Free up the memory held by CTF type and CTF variable objects after CTF debug
information has been emitted.  In ctfc_delete_container (), traverse the
hash_table of CTF types and CTF variables and free the memory held by the
respective objects.

gcc/ChangeLog:

	* ctfc.c (free_ctf_dtdef_cb): New function.
	(free_ctf_dvdef_cb): Likewise.
	(ctfc_delete_container): Free hash table contents.
---
 gcc/ctfc.c | 31 ++++++++++++++++++++++++++++---
 1 file changed, 28 insertions(+), 3 deletions(-)

diff --git a/gcc/ctfc.c b/gcc/ctfc.c
index 73c118e..1f961c9 100644
--- a/gcc/ctfc.c
+++ b/gcc/ctfc.c
@@ -179,6 +179,26 @@ ctf_dvd_lookup (const ctf_container_ref ctfc, dw_die_ref die)
   return NULL;
 }
 
+/* Callback function to free the CTF type from hash table.  */
+
+static int
+free_ctf_dtdef_cb (ctf_dtdef_ref * slot, void * arg ATTRIBUTE_UNUSED)
+{
+  if (slot && *slot)
+    ggc_free (*slot);
+  return 1;
+}
+
+/* Callback function to free the CTF variable from hash table.  */
+
+static int
+free_ctf_dvdef_cb (ctf_dvdef_ref * slot, void * arg ATTRIBUTE_UNUSED)
+{
+  if (slot && *slot)
+    ggc_free (*slot);
+  return 1;
+}
+
 /* Append member definition to the list.  Member list is a singly-linked list
    with list start pointing to the head.  */
 
@@ -944,11 +964,16 @@ ctfc_delete_strtab (ctf_strtable_t * strtab)
 void
 ctfc_delete_container (ctf_container_ref ctfc)
 {
-  /* FIXME - CTF container can be cleaned up now.
-     Will the ggc machinery take care of cleaning up the container structure
-     including the hash_map members etc. ?  */
   if (ctfc)
     {
+      ctfc->ctfc_types->traverse<void*, free_ctf_dtdef_cb> (NULL);
+      ctfc->ctfc_types->empty ();
+      ctfc->ctfc_types = NULL;
+
+      ctfc->ctfc_vars->traverse<void*, free_ctf_dvdef_cb> (NULL);
+      ctfc->ctfc_vars->empty ();
+      ctfc->ctfc_types = NULL;
+
       ctfc_delete_strtab (&ctfc->ctfc_strtable);
       ctfc_delete_strtab (&ctfc->ctfc_aux_strtable);
       if (ctfc->ctfc_vars_list)
-- 
1.8.3.1