Change enable_thread_stack_temporaries to an RAII class

This started as a patch to change enable_thread_stack_temporaries to
be an RAII class, but then I noticed that this code used a VEC, so I
went ahead and did a bit more C++-ification, changing
stack_temporaries_enabled to a bool and changing stack_temporaries to
a std::vector.

Regression tested by the buildbot.

gdb/ChangeLog
2018-03-08  Tom Tromey  <tom@tromey.com>

	* infcall.c (struct call_return_meta_info)
	<stack_temporaries_enabled>: Remove.
	(get_call_return_value, call_function_by_hand_dummy): Update.
	* thread.c (disable_thread_stack_temporaries): Remove.
	(enable_thread_stack_temporaries): Remove.
	(thread_stack_temporaries_enabled_p): Return bool.
	(push_thread_stack_temporary, value_in_thread_stack_temporaries)
	(get_last_thread_stack_temporary): Update.
	* eval.c (evaluate_subexp): Update.
	* gdbthread.h (class enable_thread_stack_temporaries): Now a
	class, not a function.
	(value_ptr, value_vec): Remove typedefs.
	(class thread_info) <stack_temporaries_enabled>: Now bool.
	<stack_temporaries>: Now a std::vector.
	(thread_stack_temporaries_enabled_p)
	(value_in_thread_stack_temporaries): Return bool.

1 files changed, 13 insertions, 58 deletions

diff --git a/gdb/thread.c b/gdb/thread.c
index 36cfcdd..a99fbdc 100644
--- a/gdb/thread.c
+++ b/gdb/thread.c
@@ -749,55 +749,16 @@ delete_exited_threads (void)
     }
 }
 
-/* Disable storing stack temporaries for the thread whose id is
-   stored in DATA.  */
-
-static void
-disable_thread_stack_temporaries (void *data)
-{
-  ptid_t *pd = (ptid_t *) data;
-  struct thread_info *tp = find_thread_ptid (*pd);
-
-  if (tp != NULL)
-    {
-      tp->stack_temporaries_enabled = 0;
-      VEC_free (value_ptr, tp->stack_temporaries);
-    }
-
-  xfree (pd);
-}
-
-/* Enable storing stack temporaries for thread with id PTID and return a
-   cleanup which can disable and clear the stack temporaries.  */
-
-struct cleanup *
-enable_thread_stack_temporaries (ptid_t ptid)
-{
-  struct thread_info *tp = find_thread_ptid (ptid);
-  ptid_t  *data;
-  struct cleanup *c;
-
-  gdb_assert (tp != NULL);
-
-  tp->stack_temporaries_enabled = 1;
-  tp->stack_temporaries = NULL;
-  data = XNEW (ptid_t);
-  *data = ptid;
-  c = make_cleanup (disable_thread_stack_temporaries, data);
-
-  return c;
-}
-
-/* Return non-zero value if stack temporaies are enabled for the thread
+/* Return true value if stack temporaies are enabled for the thread
    with id PTID.  */
 
-int
+bool
 thread_stack_temporaries_enabled_p (ptid_t ptid)
 {
   struct thread_info *tp = find_thread_ptid (ptid);
 
   if (tp == NULL)
-    return 0;
+    return false;
   else
     return tp->stack_temporaries_enabled;
 }
@@ -810,29 +771,23 @@ push_thread_stack_temporary (ptid_t ptid, struct value *v)
   struct thread_info *tp = find_thread_ptid (ptid);
 
   gdb_assert (tp != NULL && tp->stack_temporaries_enabled);
-  VEC_safe_push (value_ptr, tp->stack_temporaries, v);
+  tp->stack_temporaries.push_back (v);
 }
 
-/* Return 1 if VAL is among the stack temporaries of the thread
-   with id PTID.  Return 0 otherwise.  */
+/* Return true if VAL is among the stack temporaries of the thread
+   with id PTID.  Return false otherwise.  */
 
-int
+bool
 value_in_thread_stack_temporaries (struct value *val, ptid_t ptid)
 {
   struct thread_info *tp = find_thread_ptid (ptid);
 
   gdb_assert (tp != NULL && tp->stack_temporaries_enabled);
-  if (!VEC_empty (value_ptr, tp->stack_temporaries))
-    {
-      struct value *v;
-      int i;
+  for (struct value *v : tp->stack_temporaries)
+    if (v == val)
+      return true;
 
-      for (i = 0; VEC_iterate (value_ptr, tp->stack_temporaries, i, v); i++)
-	if (v == val)
-	  return 1;
-    }
-
-  return 0;
+  return false;
 }
 
 /* Return the last of the stack temporaries for thread with id PTID.
@@ -845,8 +800,8 @@ get_last_thread_stack_temporary (ptid_t ptid)
   struct thread_info *tp = find_thread_ptid (ptid);
 
   gdb_assert (tp != NULL);
-  if (!VEC_empty (value_ptr, tp->stack_temporaries))
-    lastval = VEC_last (value_ptr, tp->stack_temporaries);
+  if (!tp->stack_temporaries.empty ())
+    lastval = tp->stack_temporaries.back ();
 
   return lastval;
 }