Re: C++ PATCH to aggregate returns

[Jason Merrill <jason at redhat dot com>]

Here's the tree-ssa only part of this patch, to remove the duplicate copy
of this code in cp-simplify.c.

Tested athlon-pc-linux-gnu, applied to tree-ssa.

2003-08-21  Jason Merrill  <jason@redhat.com>

	* cp-simplify.c (cp_gimplify_expr): Use simplify_aggr_init_expr.
	(cp_gimplify_init_expr): Don't call it here.
	(gimplify_aggr_init_expr): Remove.

*** cp-simplify.c.~1~	Thu Aug 21 01:25:46 2003
--- cp-simplify.c	Thu Aug 21 03:47:13 2003
*************** cp_gimplify_expr (tree *expr_p, tree *pr
*** 128,134 ****
        return 1;
  
      case AGGR_INIT_EXPR:
!       gimplify_aggr_init_expr (expr_p);
        return 1;
  
      case THROW_EXPR:
--- 128,134 ----
        return 1;
  
      case AGGR_INIT_EXPR:
!       simplify_aggr_init_expr (expr_p);
        return 1;
  
      case THROW_EXPR:
*************** cp_gimplify_init_expr (tree *expr_p, tre
*** 193,283 ****
        gimplify_expr (&to, pre_p, post_p, is_gimple_modify_expr_lhs, fb_lvalue);
        TREE_OPERAND (from, 2) = to;
        *expr_p = from;
-       gimplify_aggr_init_expr (expr_p);
      }
  }
  
- /* Replace the AGGR_INIT_EXPR at *TP with an equivalent CALL_EXPR.  */
- 
- void
- gimplify_aggr_init_expr (tree *tp)
- {
-   tree aggr_init_expr = *tp;
- 
-   /* Form an appropriate CALL_EXPR.  */
-   tree fn = TREE_OPERAND (aggr_init_expr, 0);
-   tree args = TREE_OPERAND (aggr_init_expr, 1);
-   tree slot = TREE_OPERAND (aggr_init_expr, 2);
-   tree type = TREE_TYPE (aggr_init_expr);
- 
-   tree call_expr;
-   enum style_t { ctor, arg, pcc } style;
- 
-   if (AGGR_INIT_VIA_CTOR_P (aggr_init_expr))
-     style = ctor;
- #ifdef PCC_STATIC_STRUCT_RETURN
-   else if (1)
-     style = pcc;
- #endif
-   else if (TREE_ADDRESSABLE (type))
-     style = arg;
-   else
-     /* We shouldn't build an AGGR_INIT_EXPR if we don't need any special
-        handling.  See build_cplus_new.  */
-     abort ();
- 
-   if (style == ctor || style == arg)
-     {
-       /* Pass the address of the slot.  If this is a constructor, we
- 	 replace the first argument; otherwise, we tack on a new one.  */
-       if (style == ctor)
- 	args = TREE_CHAIN (args);
- 
-       cxx_mark_addressable (slot);
-       args = tree_cons (NULL_TREE,
- 			build1 (ADDR_EXPR,
- 				build_pointer_type (TREE_TYPE (slot)),
- 				slot),
- 			args);
-     }
- 
-   call_expr = build (CALL_EXPR,
- 		     TREE_TYPE (TREE_TYPE (TREE_TYPE (fn))),
- 		     fn, args, NULL_TREE);
-   TREE_SIDE_EFFECTS (call_expr) = 1;
- 
-   if (style == arg)
-     {
-       /* Tell the backend that we've added our return slot to the argument
- 	 list.  */
-       CALL_EXPR_HAS_RETURN_SLOT_ADDR (call_expr) = 1;
-       /* And don't let anyone use the value of the call directly in a
- 	 larger expression.  */
-       TREE_TYPE (call_expr) = void_type_node;
-     }
-   else if (style == pcc)
-     {
-       /* If we're using the non-reentrant PCC calling convention, then we
- 	 need to copy the returned value out of the static buffer into the
- 	 SLOT.  */
-       int old_ac = flag_access_control;
- 
-       flag_access_control = 0;
-       call_expr = build_aggr_init (slot, call_expr,
- 				   DIRECT_BIND | LOOKUP_ONLYCONVERTING);
-       flag_access_control = old_ac;
-     }
- 
-   /* We want to use the value of the initialized location as the
-      result.  */
-   call_expr = build (COMPOUND_EXPR, type,
- 		     call_expr, slot);
- 
-   /* Replace the AGGR_INIT_EXPR with the CALL_EXPR.  */
-   TREE_CHAIN (call_expr) = TREE_CHAIN (aggr_init_expr);
-   *tp = call_expr;
- }
- 
  /* Gimplify a MUST_NOT_THROW_EXPR.  */
  
  static void
--- 193,201 ----