On Fri, Apr 11, 2008 at 12:41 PM, Ian Lance Taylor <[EMAIL PROTECTED]> wrote:
> "Mohamed Shafi" <[EMAIL PROTECTED]> writes:
>
> > I have noticed that when strict_low_part is used in a patten we need
> > to use '+' as the constraint modifier if any constraints are used in
> > the patterns.
> > Why is this so?
>
> Using strict_low_part implies that the register or memory location is
> neither a pure input nor a pure output. It is both an input and an
> output. Therefore a '+' constraint is appropriate.
Thanks for the reply.
In cris i saw this patten
(define_insn "*andhi_lowpart"
[(set (strict_low_part
(match_operand:HI 0 "register_operand" "=r,r, r,r,r,r"))
(and:HI (match_operand:HI 1 "register_operand" "%0,0, 0,0,0,r")
(match_operand:HI 2 "general_operand" "r,Q>,L,O,g,!To")))]
Here = is used.
So when you say appropriate you mean to say that its not mandatory to
use '+' but '=' also suffices?
Regards,
Shafi
