gcc_assert (known_le (msize, (unsigned int) UNITS_PER_WORD)
|| known_eq (msize, GET_MODE_UNIT_SIZE (GET_MODE (x))));
- result = simplify_gen_subreg (mode, x, GET_MODE (x),
- subreg_highpart_offset (mode, GET_MODE (x)));
- gcc_assert (result);
-
- /* simplify_gen_subreg is not guaranteed to return a valid operand for
- the target if we have a MEM. gen_highpart must return a valid operand,
- emitting code if necessary to do so. */
- if (MEM_P (result))
+ /* gen_lowpart_common handles a lot of special cases due to needing to handle
+ paradoxical subregs; it only calls simplify_gen_subreg when certain that
+ it will produce something meaningful. The only case we need to handle
+ specially here is MEM. */
+ if (MEM_P (x))
{
- result = validize_mem (result);
- gcc_assert (result);
+ poly_int64 offset = subreg_highpart_offset (mode, GET_MODE (x));
+ return adjust_address (x, mode, offset);
}
+ result = simplify_gen_subreg (mode, x, GET_MODE (x),
+ subreg_highpart_offset (mode, GET_MODE (x)));
+ /* Since we handle MEM directly above, we should never get a MEM back
+ from simplify_gen_subreg. */
+ gcc_assert (result && !MEM_P (result));
+
return result;
}