+2010-12-30 Ulrich Weigand <Ulrich.Weigand@de.ibm.com>
+
+ * emit-rtl.c (set_mem_attributes_minus_bitpos): Explicitly derive
+ default values from MEM mode if no memory attributes are present.
+ Do not use mode alignment, even on STRICT_ALIGNMENT targets, when
+ called with an expression (not a type).
+
2010-12-30 H.J. Lu <hongjiu.lu@intel.com>
* config/i386/i386.c (upper_128bits_state): Remove comments.
set_mem_attributes_minus_bitpos (rtx ref, tree t, int objectp,
HOST_WIDE_INT bitpos)
{
- alias_set_type alias = MEM_ALIAS_SET (ref);
- tree expr = MEM_EXPR (ref);
- rtx offset = MEM_OFFSET (ref);
- rtx size = MEM_SIZE (ref);
- unsigned int align = MEM_ALIGN (ref);
+ alias_set_type alias;
+ tree expr = NULL;
+ rtx offset = NULL_RTX;
+ rtx size = NULL_RTX;
+ unsigned int align = BITS_PER_UNIT;
HOST_WIDE_INT apply_bitpos = 0;
tree type;
&& TREE_CODE (type) != COMPLEX_TYPE)
MEM_SCALAR_P (ref) = 1;
+ /* Default values from pre-existing memory attributes if present. */
+ if (MEM_ATTRS (ref))
+ {
+ /* ??? Can this ever happen? Calling this routine on a MEM that
+ already carries memory attributes should probably be invalid. */
+ expr = MEM_EXPR (ref);
+ offset = MEM_OFFSET (ref);
+ size = MEM_SIZE (ref);
+ align = MEM_ALIGN (ref);
+ }
+
+ /* Otherwise, default values from the mode of the MEM reference. */
+ else if (GET_MODE (ref) != BLKmode)
+ {
+ /* Respect mode size. */
+ size = GEN_INT (GET_MODE_SIZE (GET_MODE (ref)));
+ /* ??? Is this really necessary? We probably should always get
+ the size from the type below. */
+
+ /* Respect mode alignment for STRICT_ALIGNMENT targets if T is a type;
+ if T is an object, always compute the object alignment below. */
+ if (STRICT_ALIGNMENT && TYPE_P (t))
+ align = GET_MODE_ALIGNMENT (GET_MODE (ref));
+ /* ??? If T is a type, respecting mode alignment may *also* be wrong
+ e.g. if the type carries an alignment attribute. Should we be
+ able to simply always use TYPE_ALIGN? */
+ }
+
/* We can set the alignment from the type if we are making an object,
this is an INDIRECT_REF, or if TYPE_ALIGN_OK. */
if (objectp || TREE_CODE (t) == INDIRECT_REF || TYPE_ALIGN_OK (type))