[C PATCH] Discard P - (P + CST) optimization in pointer_diff (PR c/61240)

[Jeff Law]

On 08/06/14 13:45, DJ Delorie wrote:
>>> That's one of the things that would be largely made irrelevant by
>>> DJ's proposed changes.  Instead of using PSImode,
>>
>> What’s PSImode?
>
> PSImode is a mode with more precision than HImode, but less than SImode.
>
>>> we'd be able to define modes of precisely the number of bits one
>>> of these targets needs.
>
> Not quite, Jeff.  We still use PSImode but now it has a known defined
> precision, not just "fits in SImode", and may correspond to one of the
> __intN types.
Ah, cool, I didn't know all that was in.  Glad to know that we can 
precisely define the precision of the partial modes.

> There's still lots of places in gcc that use SIZE where they should
> use PRECISION.
Yea, I suspect this is rather pervasive.

Jeff