Fix PR 2520, a problem with structure parameter passing.

	* config/ia64/ia64.h (FUNCTION_ARG_BOUNDARY): Return 128 if argument
	requires more than 64 bits of alignment.

From-SVN: r41269

gcc/ChangeLog

+2001-04-11  Jim Wilson  <wilson@redhat.com>
+
+	* config/ia64/ia64.h (FUNCTION_ARG_BOUNDARY): Return 128 if argument
+	requires more than 64 bits of alignment.
+
 2001-04-11  Neil Booth  <neil@daikokuya.demon.co.uk>
 
 	* cpplib.c (do_line): Sanity check iff enable checking.

gcc/config/ia64/ia64.h

@@ -1382,11 +1382,15 @@ do {									\
 /* If defined, a C expression that gives the alignment boundary, in bits, of an
    argument with the specified mode and type.  */
 
-/* Arguments larger than 64 bits require 128 bit alignment.  */
+/* Arguments with alignment larger than 8 bytes start at the next even
+   boundary.  See ia64_function_arg.  */
 
 #define FUNCTION_ARG_BOUNDARY(MODE, TYPE) \
-  (((((MODE) == BLKmode ? int_size_in_bytes (TYPE) : GET_MODE_SIZE (MODE)) \
-     + UNITS_PER_WORD - 1) / UNITS_PER_WORD) > 1 ? 128 : PARM_BOUNDARY)
+  (((TYPE) ? (TYPE_ALIGN (TYPE) > 8 * BITS_PER_UNIT)		\
+    : (((((MODE) == BLKmode					\
+	  ? int_size_in_bytes (TYPE) : GET_MODE_SIZE (MODE))	\
+	 + UNITS_PER_WORD - 1) / UNITS_PER_WORD) > 1))		\
+    ? 128 : PARM_BOUNDARY)
 
 /* A C expression that is nonzero if REGNO is the number of a hard register in
    which function arguments are sometimes passed.  This does *not* include