On 4/11/19 12:08 AM, David Hildenbrand wrote:
> + read_vec_element_i32(sum, get_field(s->fields, v3), 1, ES_32);
> + for (i = 0; i < 4; i++) {
> + read_vec_element_i32(tmp, get_field(s->fields, v2), i, ES_32);
> + tcg_gen_add_i32(sum, sum, tmp);
> + tcg_gen_setcond_i32(TCG_COND_LTU, tmp, sum, tmp);
> + tcg_gen_add_i32(sum, sum, tmp);
> + }
> + zero_vec(get_field(s->fields, v1));
> + write_vec_element_i32(sum, get_field(s->fields, v1), 1, ES_32);
It seems like it should be possible to implement this with i64, and fold the
carry around at the end -- 2 insns instead of 12 for managing carry. But I
can't quite tell if that produces the same results.
You could use
tcg_gen_add2_i32(sum, tmp, sum, zero, tmp, zero);
tcg_gen_add_i32(sum, sum, tmp);
instead of computing carry manually with setcond.
That said, your code exactly matches the language in the manual, so
Reviewed-by: Richard Henderson <[email protected]>
r~
