59d7c14eef
While we can store constants via constrants on INDEX_op_st_i32 et al, we weren't able to spill constants to backing store. Add a new backend interface, tcg_out_sti, which may store the constant (and is allowed to fail). Rearrange the temp_* helpers so that we only attempt to directly store a constant when the temp is becoming dead/free. Signed-off-by: Richard Henderson <rth@twiddle.net>