reload.c (find_reloads_toplev): Reload a paradoxical subreg of a mem if the…

reload.c (find_reloads_toplev): Reload a paradoxical subreg of a mem if the address is a mode_dependent_address_p.

        * reload.c (find_reloads_toplev): Reload a paradoxical subreg of a
        mem if the address is a mode_dependent_address_p.

From-SVN: r35280

gcc/ChangeLog

+Wed Jul 26 19:44:05 2000   Hans-Peter Nilsson  <hp@axis.com>
+
+	* reload.c (find_reloads_toplev): Reload a paradoxical subreg of a
+	mem if the address is a mode_dependent_address_p.
+
 2000-07-26  Kazu Hirata  <kazu@hxi.com>
 
 	* h8300.c (print_operand): Print ":8" when the 'R' operand is

gcc/reload.c

@@ -4335,6 +4335,25 @@ find_reloads_toplev (x, opnum, type, ind_levels, is_set_dest, insn,
 	x = find_reloads_subreg_address (x, 1, opnum, type, ind_levels,
 					 insn);
     }
+  else if (code == SUBREG && GET_CODE (SUBREG_REG (x)) == MEM
+	   && (GET_MODE_SIZE (GET_MODE (x))
+	       > GET_MODE_SIZE (GET_MODE (SUBREG_REG (x))))
+	   && mode_dependent_address_p (XEXP (SUBREG_REG (x), 0)))
+    {
+      /* A paradoxical subreg will simply have the mode of the access
+	 changed, so we need to reload such a memory operand to stabilize
+	 the meaning of the memory access.  */
+      enum machine_mode subreg_mode = GET_MODE (SUBREG_REG (x));
+
+      if (is_set_dest)
+	push_reload (NULL_RTX, SUBREG_REG (x), NULL_PTR, &SUBREG_REG (x),
+		     find_valid_class (subreg_mode, SUBREG_WORD (x)),
+		     VOIDmode, subreg_mode, 0, 0, opnum, type);
+      else
+	push_reload (SUBREG_REG (x), NULL_RTX, &SUBREG_REG (x), NULL_PTR,
+		     find_valid_class (subreg_mode, SUBREG_WORD (x)),
+		     subreg_mode, VOIDmode, 0, 0, opnum, type);
+    }
 
   for (copied = 0, i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
     {
@@ -5530,7 +5549,7 @@ find_reloads_subreg_address (x, force_replace, opnum, type,
 
 /* Substitute into the current INSN the registers into which we have reloaded
    the things that need reloading.  The array `replacements'
-   says contains the locations of all pointers that must be changed
+   contains the locations of all pointers that must be changed
    and says what to replace them with.
 
    Return the rtx that X translates into; usually X, but modified.  */