(expand_call): When preserving subexpressions, don't put expensive

arguments directly into hard registers.

From-SVN: r6543

diff --git a/gcc/calls.c b/gcc/calls.c
index 898272d..4f3e61b 100644 (file)
--- a/gcc/calls.c
+++ b/gcc/calls.c
@@ -1,5 +1,5 @@
 /* Convert function calls to rtl insns, for GNU C compiler.
-   Copyright (C) 1989, 1992, 1993 Free Software Foundation, Inc.
+   Copyright (C) 1989, 1992, 1993, 1994 Free Software Foundation, Inc.
 
 This file is part of GNU CC.
 
@@ -1566,6 +1566,18 @@ expand_call (exp, target, ignore)
            = convert_modes (args[i].mode,
                             TYPE_MODE (TREE_TYPE (args[i].tree_value)),
                             args[i].value, args[i].unsignedp);
+
+       /* If the value is expensive, and we are inside an appropriately 
+          short loop, put the value into a pseudo and then put the pseudo
+          into the hard reg.  */
+
+       if ((! (GET_CODE (args[i].value) == REG
+               || (GET_CODE (args[i].value) == SUBREG
+                   && GET_CODE (SUBREG_REG (args[i].value)) == REG)))
+           && args[i].mode != BLKmode
+           && rtx_cost (args[i].value, SET) > 2
+           && preserve_subexpressions_p ())
+         args[i].value = copy_to_mode_reg (args[i].mode, args[i].value);
       }
 
 #if defined(ACCUMULATE_OUTGOING_ARGS) && defined(REG_PARM_STACK_SPACE)