On Fri, Sep 13, 2013 at 10:23 PM, Mike Stump <mikest...@comcast.net> wrote: > On Sep 13, 2013, at 1:08 AM, Richard Sandiford <rdsandif...@googlemail.com> > wrote: >>>> We don't really model that properly yet. Partial modes are just defined >>>> using something like: >>>> >>>> PARTIAL_INT_MODE (SI); > > True, but, all ports are trivial to fix so that the precision is included and > for the interface to change to include the precision. > >>> Well I was asking because if you change a GEN_INT (x) to >>> gen_int_mode (PSImode, x) then you'll end up in trunc_int_for_mode with >>> PSImode which looks at GET_MODE_PRECISION (PSImode is still >>> a SCALAR_INT_MODE_P ...). We set precision of PSImode to -1U > > Easy to fix. > >> Yeah. I don't think it makes sense to canonise PSI to 32 bits when we >> know it has fewer than 32 bits. > > Agreed. > > > Here is the patch to add precision to partial int modes. I included > switching over the rs6000 port to the new scheme so one can get a feel for > that it would look like. > > I could trivially convert the remaining ports: > > config/bfin/bfin-modes.def:PARTIAL_INT_MODE (DI); > config/m32c/m32c-modes.def:PARTIAL_INT_MODE (SI); > config/msp430/msp430-modes.def:PARTIAL_INT_MODE (SI); > config/rs6000/rs6000-modes.def:PARTIAL_INT_MODE_N (TI, 128); > config/sh/sh-modes.def:PARTIAL_INT_MODE (SI); > config/sh/sh-modes.def:PARTIAL_INT_MODE (DI); > > to the new scheme so that _all_ ports would have a precision with all partial > int modes. The newest port that I had not audited for how they use it > (msp430): > > /* 20-bit address */ > PARTIAL_INT_MODE (SI); > > So, this, trivially would be SI, 20… I would define PARTIAL_INT_MODE with > two parameters and not define PARTIAL_INT_MODE_N, if we did it for real. No > need for partial conversions here, too easy to convert things. > > Ok for the non-powerpc bits?
Can you instead of adding PARTIAL_INT_MODE_N change all existing PARTIAL_INT_MODE ()s to PARTIAL_INT_MODE_LEGACY () and change PARTIAL_INT_MODE behavior? > Want me to convert all the ports and change the interface instead of merely > extending it and submit those? I'd hate to do the work, if no one wants to > review/approve it. I volunteer to approve it (after giving target maintainers time to do so on their own). So, if you send a whole conversion patch then we don't have to play games with having both variants recognized. (now it just occurs to me we can use a variadic macro here ...?) Richard. > We've been using this scheme on our port for a while and it seems to work > nicely. > >
