tree.c (first_rtl_op): New fn.

	* tree.c (first_rtl_op): New fn.
	(unsave_expr_now): Use it.
	* print-tree.c (print_node): Likewise.
	* tree.c (has_cleanups): New fn.
	* fold-const.c (fold, case CLEANUP_POINT_EXPR): Use it.  Be more
	conservative about pushing the cleanup point down.
	* tree.h: Declare them.

From-SVN: r18023

5 files changed, 112 insertions, 38 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 472a5b3..ce452cb 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,13 @@
+1998-02-16  Jason Merrill  <jason@yorick.cygnus.com>
+
+	* tree.c (first_rtl_op): New fn.
+	(unsave_expr_now): Use it.
+	* print-tree.c (print_node): Likewise.
+	* tree.c (has_cleanups): New fn.
+	* fold-const.c (fold, case CLEANUP_POINT_EXPR): Use it.  Be more
+	conservative about pushing the cleanup point down.
+	* tree.h: Declare them.
+
 Sun Feb 15 23:28:44 1998  Jeffrey A Law  (law@cygnus.com)
 
 	* toplev.c (flag_schedule_reverse_before_reload): Delete variable.
diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index 4d021db..35d8beb 100644
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -5920,7 +5920,7 @@ fold (expr)
       /* Pull arithmetic ops out of the CLEANUP_POINT_EXPR where
          appropriate.  */
     case CLEANUP_POINT_EXPR:
-      if (! TREE_SIDE_EFFECTS (arg0))
+      if (! has_cleanups (arg0))
 	return TREE_OPERAND (t, 0);
 
       {
@@ -5941,12 +5941,14 @@ fold (expr)
 	  {
 	    arg01 = TREE_OPERAND (arg0, 1);
 
-	    if (! TREE_SIDE_EFFECTS (arg00))
+	    if (TREE_CONSTANT (arg00)
+		|| ((code0 == TRUTH_ANDIF_EXPR || code0 == TRUTH_ORIF_EXPR)
+		    && ! has_cleanups (arg00)))
 	      return fold (build (code0, type, arg00,
 				  fold (build1 (CLEANUP_POINT_EXPR,
 						TREE_TYPE (arg01), arg01))));
 
-	    if (! TREE_SIDE_EFFECTS (arg01))
+	    if (TREE_CONSTANT (arg01))
 	      return fold (build (code0, type,
 				  fold (build1 (CLEANUP_POINT_EXPR,
 						TREE_TYPE (arg00), arg00)),
diff --git a/gcc/print-tree.c b/gcc/print-tree.c
index f075f0b..5b81bc5 100644
--- a/gcc/print-tree.c
+++ b/gcc/print-tree.c
@@ -547,29 +547,10 @@ print_node (file, prefix, node, indent)
 	  return;
 	}
 
-      first_rtl = len = tree_code_length[(int) TREE_CODE (node)];
-      /* These kinds of nodes contain rtx's, not trees,
+      len = tree_code_length[(int) TREE_CODE (node)];
+      /* Some nodes contain rtx's, not trees,
 	 after a certain point.  Print the rtx's as rtx's.  */
-      switch (TREE_CODE (node))
-	{
-	case SAVE_EXPR:
-	  first_rtl = 2;
-	  break;
-	case CALL_EXPR:
-	  first_rtl = 2;
-	  break;
-	case METHOD_CALL_EXPR:
-	  first_rtl = 3;
-	  break;
-	case WITH_CLEANUP_EXPR:
-	  /* Should be defined to be 2.  */
-	  first_rtl = 1;
-	  break;
-	case RTL_EXPR:
-	  first_rtl = 0;
-	default:
-	  break;
-	}
+      first_rtl = first_rtl_op (TREE_CODE (node));
       for (i = 0; i < len; i++)
 	{
 	  if (i >= first_rtl)
diff --git a/gcc/tree.c b/gcc/tree.c
index 9659cd0..1f13532 100644
--- a/gcc/tree.c
+++ b/gcc/tree.c
@@ -2387,6 +2387,31 @@ unsave_expr (expr)
   return t;
 }
 
+/* Returns the index of the first non-tree operand for CODE, or the number
+   of operands if all are trees.  */
+
+int
+first_rtl_op (code)
+     enum tree_code code;
+{
+  switch (code)
+    {
+    case SAVE_EXPR:
+      return 2;
+    case RTL_EXPR:
+      return 0;
+    case CALL_EXPR:
+      return 2;
+    case WITH_CLEANUP_EXPR:
+      /* Should be defined to be 2.  */
+      return 1;
+    case METHOD_CALL_EXPR:
+      return 3;
+    default:
+      return tree_code_length [(int) code];
+    }
+}
+
 /* Modify a tree in place so that all the evaluate only once things
    are cleared out.  Return the EXPR given.  */
 
@@ -2402,12 +2427,11 @@ unsave_expr_now (expr)
     return expr;
 
   code = TREE_CODE (expr);
-  first_rtl = tree_code_length [(int) code];
+  first_rtl = first_rtl_op (code);
   switch (code)
     {
     case SAVE_EXPR:
       SAVE_EXPR_RTL (expr) = 0;
-      first_rtl = 2;
       break;
 
     case TARGET_EXPR:
@@ -2419,7 +2443,6 @@ unsave_expr_now (expr)
       /* I don't yet know how to emit a sequence multiple times.  */
       if (RTL_EXPR_SEQUENCE (expr) != 0)
 	abort ();
-      first_rtl = 0;
       break;
 
     case CALL_EXPR:
@@ -2434,16 +2457,6 @@ unsave_expr_now (expr)
 	      exp = TREE_CHAIN (exp);
 	    }
 	}
-      first_rtl = 2;
-      break;
-
-    case WITH_CLEANUP_EXPR:
-      /* Should be defined to be 2.  */
-      first_rtl = 1;
-      break;
-
-    case METHOD_CALL_EXPR:
-      first_rtl = 3;
       break;
 
     default:
@@ -2561,6 +2574,64 @@ contains_placeholder_p (exp)
       return 0;
     }
 }
+
+/* Return 1 if EXP contains any expressions that produce cleanups for an
+   outer scope to deal with.  Used by fold.  */
+
+int
+has_cleanups (exp)
+     tree exp;
+{
+  int i, nops, cmp;
+
+  if (! TREE_SIDE_EFFECTS (exp))
+    return 0;
+
+  switch (TREE_CODE (exp))
+    {
+    case TARGET_EXPR:
+    case WITH_CLEANUP_EXPR:
+      return 1;
+
+    case CLEANUP_POINT_EXPR:
+      return 0;
+
+    case CALL_EXPR:
+      for (exp = TREE_OPERAND (exp, 1); exp; exp = TREE_CHAIN (exp))
+	{
+	  cmp = has_cleanups (TREE_VALUE (exp));
+	  if (cmp)
+	    return cmp;
+	}
+      return 0;
+
+    default:
+      break;
+    }
+
+  /* This general rule works for most tree codes.  All exceptions should be
+     handled above.  If this is a language-specific tree code, we can't
+     trust what might be in the operand, so say we don't know
+     the situation.  */
+  if ((int) TREE_CODE (exp) >= (int) LAST_AND_UNUSED_TREE_CODE)
+    return -1;
+
+  nops = first_rtl_op (TREE_CODE (exp));
+  for (i = 0; i < nops; i++)
+    if (TREE_OPERAND (exp, i) != 0)
+      {
+	int type = TREE_CODE_CLASS (TREE_CODE (TREE_OPERAND (exp, i)));
+	if (type == 'e' || type == '<' || type == '1' || type == '2'
+	    || type == 'r' || type == 's')
+	  {
+	    cmp = has_cleanups (TREE_OPERAND (exp, i));
+	    if (cmp)
+	      return cmp;
+	  }
+      }
+
+  return 0;
+}
 
 /* Given a tree EXP, a FIELD_DECL F, and a replacement value R,
    return a tree with all occurrences of references to F in a
diff --git a/gcc/tree.h b/gcc/tree.h
index 093304a..39ec303 100644
--- a/gcc/tree.h
+++ b/gcc/tree.h
@@ -1490,6 +1490,11 @@ extern int lvalue_or_else		PROTO((tree, char *));
 
 extern tree save_expr			PROTO((tree));
 
+/* Returns the index of the first non-tree operand for CODE, or the number
+   of operands if all are trees.  */
+
+extern int first_rtl_op			PROTO((enum tree_code));
+
 /* unsave_expr (EXP) returns an expression equivalent to EXP but it
    can be used multiple times and will evaluate EXP, in it's entirety
    each time.  */
@@ -1509,6 +1514,11 @@ extern tree unsave_expr_now		PROTO((tree));
 
 extern int contains_placeholder_p	PROTO((tree));
 
+/* Return 1 if EXP contains any expressions that produce cleanups for an
+   outer scope to deal with.  Used by fold.  */
+
+extern int has_cleanups			PROTO((tree));
+
 /* Given a tree EXP, a FIELD_DECL F, and a replacement value R,
    return a tree with all occurrences of references to F in a
    PLACEHOLDER_EXPR replaced by R.   Note that we assume here that EXP