Re: Abt long long support

["Mohamed Shafi" <shafitvm at gmail dot com>]

Thanks for the reply

My target (non gcc/private one) fails for long long testcases and
there are cases (with long long) which gets through, but not with the
right output. When i replace long long with long the testcases runs
fine, even those giving wrong output.
The target is not able to compile properly for simple statements like

long long a = 10;

So when i looked into the .md file i saw no patterns with DI machine
mode ,used for long long(am i right?), execpt

define_insn "adddi3"  and   define_insn "subdi3"

The .md file says that this is to prevent gcc from synthesising it,
though i didnt understand what that means.

Thats when i started to doubt if the backend provides support for long long.But
if what Rask is saying is true , which has to be i guess since you
guys are saying that,then middle end should take care of synthesizing
long long.
The 32 bit target has this defined in the .h file
LONG_TYPE_SIZE 		32
LONG_LONG_TYPE_SIZE 	64

Is there anything else thati should provide in the bach end to make
sure that rest of gcc
is synthesizing long long properly?

Any thoughts?



On 11/7/06, Rask Ingemann Lambertsen <rask@sygehus.dk> wrote:
> On Mon, Nov 06, 2006 at 10:52:00AM +0530, Mohamed Shafi wrote:
> > Hello all,
> >
> > Looking at a .md file of a backend it there a way to know whether a
> > target supports long long
> > Should i look for patterns with machine mode DI?
>
>    No. For example, 8-bit, 16-bit and 32-bit targets should normally not
> define patterns such as anddi3, iordi3 and xordi3. It is possible that a
> target could have no patterns with mode DI but still support long long,
> although probably with significant slowdown. E.g. the middle end can
> synthesize adddi3 and subdi3 from SImode operations, but I think most
> targets can easily improve 10x in terms of speed and size on that code.
>
>    Watch out for targets where units are larger than 8 bits. An example is
> the c4x where a unit is 32-bits and HImode is 64-bits.
>
> > Is there some other way?
>
>    This depends a lot on exactly what you mean when you say support, but
> grep for LONG_TYPE_SIZE and LONG_LONG_TYPE_SIZE in the .h file and compare
> the two.
>
> --
> Rask Ingemann Lambertsen