calls.c (store_one_arg): Pass correct alignment to emit_push_insn for non-BLKmode values.

	* calls.c (store_one_arg): Pass correct alignment to
	emit_push_insn for non-BLKmode values.
	* expr.c (emit_push_insn): If STRICT_ALIGNMENT, copy to an
	unaligned stack slot via a suitably aligned slot.

From-SVN: r121736

gcc/ChangeLog

+2007-02-09  Joseph Myers  <joseph@codesourcery.com>
+
+	* calls.c (store_one_arg): Pass correct alignment to
+	emit_push_insn for non-BLKmode values.
+	* expr.c (emit_push_insn): If STRICT_ALIGNMENT, copy to an
+	unaligned stack slot via a suitably aligned slot.
+
 2007-02-08  DJ Delorie  <dj@redhat.com>
 
 	* config/m32c/m32c.c (m32c_unpend_compare): Add default to silence

gcc/calls.c

 /* Convert function calls to rtl insns, for GNU C compiler.
    Copyright (C) 1989, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
-   1999, 2000, 2001, 2002, 2003, 2004, 2005
+   1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007
    Free Software Foundation, Inc.
 
 This file is part of GCC.
@@ -4191,6 +4191,7 @@ store_one_arg (struct arg_data *arg, rtx argblock, int flags,
   else if (arg->mode != BLKmode)
     {
       int size;
+      unsigned int parm_align;
 
       /* Argument is a scalar, not entirely passed in registers.
 	 (If part is passed in registers, arg->partial says how much
@@ -4218,10 +4219,22 @@ store_one_arg (struct arg_data *arg, rtx argblock, int flags,
 		 / (PARM_BOUNDARY / BITS_PER_UNIT))
 		* (PARM_BOUNDARY / BITS_PER_UNIT));
 
+      /* Compute the alignment of the pushed argument.  */
+      parm_align = arg->locate.boundary;
+      if (FUNCTION_ARG_PADDING (arg->mode, TREE_TYPE (pval)) == downward)
+	{
+	  int pad = used - size;
+	  if (pad)
+	    {
+	      unsigned int pad_align = (pad & -pad) * BITS_PER_UNIT;
+	      parm_align = MIN (parm_align, pad_align);
+	    }
+	}
+
       /* This isn't already where we want it on the stack, so put it there.
 	 This can either be done with push or copy insns.  */
       emit_push_insn (arg->value, arg->mode, TREE_TYPE (pval), NULL_RTX,
-		      PARM_BOUNDARY, partial, reg, used - size, argblock,
+		      parm_align, partial, reg, used - size, argblock,
 		      ARGS_SIZE_RTX (arg->locate.offset), reg_parm_stack_space,
 		      ARGS_SIZE_RTX (arg->locate.alignment_pad));
 

gcc/expr.c

@@ -3643,7 +3643,8 @@ emit_push_insn (rtx x, enum machine_mode mode, tree type, rtx size,
 
   xinner = x;
 
-  if (mode == BLKmode)
+  if (mode == BLKmode
+      || (STRICT_ALIGNMENT && align < GET_MODE_ALIGNMENT (mode)))
     {
       /* Copy a block into the stack, entirely or partially.  */
 
@@ -3655,6 +3656,20 @@ emit_push_insn (rtx x, enum machine_mode mode, tree type, rtx size,
       offset = partial % (PARM_BOUNDARY / BITS_PER_UNIT);
       used = partial - offset;
 
+      if (mode != BLKmode)
+	{
+	  /* A value is to be stored in an insufficiently aligned
+	     stack slot; copy via a suitably aligned slot if
+	     necessary.  */
+	  size = GEN_INT (GET_MODE_SIZE (mode));
+	  if (!MEM_P (xinner))
+	    {
+	      temp = assign_temp (type, 0, 1, 1);
+	      emit_move_insn (temp, xinner);
+	      xinner = temp;
+	    }
+	}
+
       gcc_assert (size);
 
       /* USED is now the # of bytes we need not copy to the stack