Short circuit evaluation of expressions in query

Say I have the following parameterized query in a function:

select * from foo where ($1 = -1 or foo.status = $1) and (…)

where the (…) part consists of more parameterized conditions similar to the first one.

Suppose that at runtime, $1 is supplied a value of -1, does the foo.status = $1 condition still have to be evaluated?

Assuming the $1 = -1 case, should the above query be as fast as the following?

select * from foo where (…)

Thanks
Jimmy