Create vector types in handle_vector_size_attribute

["Paolo Bonzini" <bonzini at gnu dot org>]

Following what was hinted by rth last February, this patch always creates the
requested vector types in handle_vector_size_attribute instead of relying on
those created by tree.c.  This ways, also, the missing V4QI type is made
available as char __attribute__ ((vector_size (4))).  I can provide a followup
patch to deprecate specification of vector types with the mode attribute.  I
took the opportunity to clean up the vector type creation routine while I was
making it public.

This patch has also a small tweak so that a vector size of 4 * sizeof (xyz) is
accepted.

Ok for mainline?

Paolo

Attachment: gcc-extend-vector-size-attribute.patch
Description: Binary data