参照元†
返り値†
/* Vector types need to re-check the target flags each time we report
the machine mode. We need to do this because attribute target can
change the result of vector_mode_supported_p and have_regs_of_mode
on a per-function basis. Thus the TYPE_MODE of a VECTOR_TYPE can
change on a per-function basis. */
/* ??? Possibly a better solution is to run through all the types
referenced by a function and re-compute the TYPE_MODE once, rather
than make the TYPE_MODE macro call a function. */
machine_mode
vector_type_mode (const_tree t)
{
machine_mode mode;
gcc_assert (TREE_CODE (t) == VECTOR_TYPE);
mode = t->type_common.mode;
if (VECTOR_MODE_P (mode)
&& (!targetm.vector_mode_supported_p (mode)
|| !have_regs_of_mode[mode]))
{
scalar_int_mode innermode;
/* For integers, try mapping it to a same-sized scalar mode. */
if (is_int_mode (TREE_TYPE (t)->type_common.mode, &innermode))
{
poly_int64 size = (TYPE_VECTOR_SUBPARTS (t)
* GET_MODE_BITSIZE (innermode));
scalar_int_mode mode;
if (int_mode_for_size (size, 0).exists (&mode)
&& have_regs_of_mode[mode])
return mode;
}
return BLKmode;
}
return mode;
}
コメント†