WordPtr,IntPtr,IntMax,WordMax

[John Meacham]

On Tue, May 02, 2006 at 03:29:16AM +0000, Aaron Denney wrote:
> On 2006-04-29, Manuel M T Chakravarty <chak at cse.unsw.edu.au> wrote:
> > Am Donnerstag, den 06.04.2006, 16:37 -0700 schrieb John Meacham:
> >> On Thu, Apr 06, 2006 at 04:28:01PM -0700, John Meacham wrote:
> >> > I was curious if ghc could support the following basic types, they will
> >> > likely just be aliases of existing types.
> >> > 
> >> > WordPtr uintptr_t
> >> > WordMax uintmax_t
> >> > IntPtr  intptr_t
> >> > IntMax  intmax_t
> >> > 
> >> > all these C types are defined by ISO C so should be available,
> >> > otherwise, they are easy enough to generate in ghcs autoconf script.
> >> > 
> >> > jhc provides these under these names in Data.Word and Data.Int.
> >> > they would be useful for writing jhc/ghc portable low level code, and
> >> > writing 32/64 bit safe code.
> >> 
> >> oh, I forgot the all important conversion routines,
> >> 
> >> ptrToWordPtr :: Ptr a -> WordPtr
> >> wordPtrToPtr :: WordPtr -> Ptr a
> >> 
> >> ptrToIntPtr :: Ptr a -> IntPtr
> >> intPtrToPtr :: IntPtr -> Ptr a
> >> 
> >> jhc makes these available in Jhc.Addr, but if ghc decides to provide
> >> them in a common spot (Foreign.Ptr maybe?)
> >> 
> >> then I will have jhc follow suit.
> >> 
> >> I'd also propose these be added to the FFI standard.
> >
> > I collect additions to the FFI on the Haskell' wiki:
> >
> >   http://hackage.haskell.org/trac/haskell-prime/wiki/ForeignFunctionInterface
> >
> > I added a note about these types.  Any other ISO C types that we should
> > include?
> 
> complex <foo>.

not ISO C, but I think they would be very cool to provide

 http://gcc.gnu.org/onlinedocs/gcc-4.0.0/gcc/Vector-Extensions.html

various vector (SSE, MMX, SIMD) types that are machine independent and
compiled to whatever vector processing instructions the underlying arch
supports. (pretty much all support some sort of them nowadays)

also, incidentally, for anyone on x86 that cares about math performance,
use -optc-fsse2 to make it use the much nicer math coprocessor available
on modern x86 cpus. (this is the default on x86-64)

        John

-- 
John Meacham - ⑆repetae.net⑆john⑈