tree.def (RTL_EXPR): Update documentation.

	* tree.def (RTL_EXPR): Update documentation.
	* tree.h (RTL_EXPR_HAS_NO_SCOPE): New macro.
	* expr.c (expand_expr): Handle RTL_EXPR_HAS_NO_SCOPE.
	* function.c (preserve_rtl_expr_temp): New function.
	(preserve_rtl_expr_temps): Likewise.
	(preserve_rtl_expr_result): Use it.

From-SVN: r32344

1 files changed, 33 insertions, 5 deletions

diff --git a/gcc/function.c b/gcc/function.c
index 78c5ab8..fe7f61b 100644
--- a/gcc/function.c
+++ b/gcc/function.c
@@ -293,6 +293,7 @@ static void mark_function_chain PARAMS ((void *));
 static void prepare_function_start PARAMS ((void));
 static void do_clobber_return_reg PARAMS ((rtx, void *));
 static void do_use_return_reg PARAMS ((rtx, void *));
+static void preserve_rtl_expr_temp PARAMS ((struct temp_slot *));
 
 /* Pointer to chain of `struct function' for containing functions.  */
 struct function *outer_function_chain;
@@ -1129,6 +1130,36 @@ preserve_temp_slots (x)
       p->level--;
 }
 
+/* Preserve the temporary slot given by P (originally created during
+   the building of an RTL_EXPR) at least as long as things in our
+   current scope.  */
+
+static void
+preserve_rtl_expr_temp (p)
+     struct temp_slot *p;
+{
+  /* Set the slot level to that of the currently prevailing scope.  */
+  p->level = MIN (p->level, temp_slot_level);
+  /* This slot is no longer associated with the RTL_EXPR from which it
+     originated.  */
+  p->rtl_expr = NULL_TREE;
+}
+
+/* Preserve the temporary slots created during the building of the
+   RTL_EXPR given by T at least as long as things in our current
+   scope.  */
+
+void
+preserve_rtl_expr_temps (t)
+     tree t;
+{
+  struct temp_slot *p;
+
+  for (p = temp_slots; p; p = p->next)
+    if (p->in_use && p->rtl_expr == t)
+      preserve_rtl_expr_temp (p);
+}
+
 /* X is the result of an RTL_EXPR.  If it is a temporary slot associated
    with that RTL_EXPR, promote it into a temporary slot at the present
    level so it will not be freed when we free slots made in the
@@ -1148,11 +1179,8 @@ preserve_rtl_expr_result (x)
   /* If we can find a match, move it to our level unless it is already at
      an upper level.  */
   p = find_temp_slot_from_address (XEXP (x, 0));
-  if (p != 0)
-    {
-      p->level = MIN (p->level, temp_slot_level);
-      p->rtl_expr = 0;
-    }
+  if (p)
+    preserve_rtl_expr_temp (p);
 
   return;
 }