(('unpack_32_2x16_split_x', a), ('u2u16', a), 'options->lower_unpack_32_2x16_split || options->lower_pack_split'),
(('unpack_32_2x16_split_y', a), ('u2u16', ('ushr', a, 16)), 'options->lower_unpack_32_2x16_split || options->lower_pack_split'),
+ (('unpack_64_2x32_split_x', ('ushr', a, 32)), ('unpack_64_2x32_split_y', a), '!options->lower_unpack_64_2x32_split'),
+ (('u2u32', ('ushr', 'a@64', 32)), ('unpack_64_2x32_split_y', a), '!options->lower_unpack_64_2x32_split'),
+
# Useless masking before unpacking
(('unpack_half_2x16_split_x', ('iand', a, 0xffff)), ('unpack_half_2x16_split_x', a)),
(('unpack_32_2x16_split_x', ('iand', a, 0xffff)), ('unpack_32_2x16_split_x', a)),