i960.c (i960_setup_incoming_varargs): Create a new rtx for comparing the argument...

        * config/i960/i960.c (i960_setup_incoming_varargs): Create a
        new rtx for comparing the argument pointer against zero.
        (i960_va_start): Similarly.

From-SVN: r57897

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index eb30326e1c95882ee4cb722543a2376078058388..13f3151d2753016e74e6ba93b70ef094f14347ac 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2002-10-07  Richard Henderson  <rth@redhat.com>
+
+       * config/i960/i960.c (i960_setup_incoming_varargs): Create a
+       new rtx for comparing the argument pointer against zero.
+       (i960_va_start): Similarly.
+
 2002-10-07  Richard Henderson  <rth@redhat.com>
 
        * config/i960/i960.md (*): Use TFmode, not XFmode.

diff --git a/gcc/config/i960/i960.c b/gcc/config/i960/i960.c
index bde671052559853f194ce915ca1685215bdbc543..f353c729ac2d07456e860ce1add987015243b37b 100644 (file)
--- a/gcc/config/i960/i960.c
+++ b/gcc/config/i960/i960.c
@@ -2552,16 +2552,20 @@ i960_setup_incoming_varargs (cum, mode, type, pretend_size, no_rtl)
   if (cum->ca_nstackparms == 0 && first_reg < NPARM_REGS && !no_rtl)
     {
       rtx label = gen_label_rtx ();
-      rtx regblock;
+      rtx regblock, fake_arg_pointer_rtx;
 
-      /* If arg_pointer_rtx == 0, no arguments were passed on the stack
+      /* Use a different rtx than arg_pointer_rtx so that cse and friends
+        can go on believing that the argument pointer can never be zero.  */
+      fake_arg_pointer_rtx = gen_raw_REG (Pmode, ARG_POINTER_REGNUM);
+
+      /* If the argument pointer is 0, no arguments were passed on the stack
         and we need to allocate a chunk to save the registers (if any
         arguments were passed on the stack the caller would allocate the
         48 bytes as well).  We must allocate all 48 bytes (12*4) because
         va_start assumes it.  */
-      emit_insn (gen_cmpsi (arg_pointer_rtx, const0_rtx));
+      emit_insn (gen_cmpsi (fake_arg_pointer_rtx, const0_rtx));
       emit_jump_insn (gen_bne (label));
-      emit_insn (gen_rtx_SET (VOIDmode, arg_pointer_rtx,
+      emit_insn (gen_rtx_SET (VOIDmode, fake_arg_pointer_rtx,
                              stack_pointer_rtx));
       emit_insn (gen_rtx_SET (VOIDmode, stack_pointer_rtx,
                              memory_address (SImode,
@@ -2598,6 +2602,7 @@ i960_va_start (valist, nextarg)
      rtx nextarg ATTRIBUTE_UNUSED;
 {
   tree s, t, base, num;
+  rtx fake_arg_pointer_rtx;
 
   /* The array type always decays to a pointer before we get here, so we
      can't use ARRAY_REF.  */
@@ -2606,7 +2611,10 @@ i960_va_start (valist, nextarg)
                build (PLUS_EXPR, unsigned_type_node, valist,
                       TYPE_SIZE_UNIT (TREE_TYPE (valist))));
 
-  s = make_tree (unsigned_type_node, arg_pointer_rtx);
+  /* Use a different rtx than arg_pointer_rtx so that cse and friends
+     can go on believing that the argument pointer can never be zero.  */
+  fake_arg_pointer_rtx = gen_raw_REG (Pmode, ARG_POINTER_REGNUM);
+  s = make_tree (unsigned_type_node, fake_arg_pointer_rtx);
   t = build (MODIFY_EXPR, unsigned_type_node, base, s);
   TREE_SIDE_EFFECTS (t) = 1;
   expand_expr (t, const0_rtx, VOIDmode, EXPAND_NORMAL);