Segfault in ghc head -fllvm

[Simon Marlow]

Don, did you recompile all the libraries after updating GHC?  We 
recently turned on TNTC, which would cause breakages if you had any 
libraries or packages compiled the old way.

Cheers,
	Simon

On 29/06/2010 04:21, Don Stewart wrote:
> This comes from a Haskell game, where  the C program was about 10x
> faster again (thanks to SSE).
>
> The C program to test against is here:
>
>      http://stackoverflow.com/questions/3115540
>
> Maybe use it as a benchmark?
>
> -- Don
>
> davidterei:
>> Too Slow :).
>>
>> I fixed a few bugs in the LLVM backend in the last 24 hours, they seem
>> to have fixed this segault (that or I'm not reproducing your results
>> right). I can compile and run this program fine with latest GHC Head
>> under both 32/64 bit Linux.
>>
>> Under 32bit I get a nice speed up with the LLVM backend but under 64
>> bit, fasm gives me about 1.5s and fllvm gives me about 1.8s which
>> isn't very good. So will have to investigate that, its quite unusual
>> for the ncg to beat llvm by anything more then 10%.
>>
>> Cheers,
>> David
>>
>> On 29 June 2010 03:32, Don Stewart<dons at galois.com>  wrote:
>>> The following vector program segfaults with the latest head snapshot,
>>>
>>>     {-# LANGUAGE BangPatterns #-}
>>>
>>>     {-
>>>         ghc 6.12.1 -O2
>>>         1.752
>>>     -}
>>>
>>>     import Data.Vector.Storable
>>>     import qualified Data.Vector.Storable as V
>>>     import Foreign
>>>     import Foreign.C.Types
>>>
>>>     -- Define a 4 element vector type
>>>     data Vec4 = Vec4 {-# UNPACK #-} !CFloat
>>>                      {-# UNPACK #-} !CFloat
>>>                      {-# UNPACK #-} !CFloat
>>>                      {-# UNPACK #-} !CFloat
>>>
>>>     ------------------------------------------------------------------------
>>>
>>>     -- Ensure we can store it in an array
>>>     instance Storable Vec4 where
>>>       sizeOf _ = sizeOf (undefined :: CFloat) * 4
>>>       alignment _ = alignment (undefined :: CFloat)
>>>
>>>       {-# INLINE peek #-}
>>>       peek p = do
>>>                  a<- peekElemOff q 0
>>>                  b<- peekElemOff q 1
>>>                  c<- peekElemOff q 2
>>>                  d<- peekElemOff q 3
>>>                  return (Vec4 a b c d)
>>>         where
>>>           q = castPtr p
>>>
>>>       {-# INLINE poke #-}
>>>       poke p (Vec4 a b c d) = do
>>>                                 pokeElemOff q 0 a
>>>                                 pokeElemOff q 1 b
>>>                                 pokeElemOff q 2 c
>>>                                 pokeElemOff q 3 d
>>>         where
>>>           q = castPtr p
>>>
>>>     ------------------------------------------------------------------------
>>>
>>>     a = Vec4 0.2 0.1 0.6 1.0
>>>     m = Vec4 0.99 0.7 0.8 0.6
>>>
>>>     add :: Vec4 ->  Vec4 ->  Vec4
>>>     {-# INLINE add #-}
>>>     add (Vec4 a b c d) (Vec4 a' b' c' d') = Vec4 (a+a') (b+b') (c+c') (d+d')
>>>
>>>     mult :: Vec4 ->  Vec4 ->  Vec4
>>>     {-# INLINE mult #-}
>>>     mult (Vec4 a b c d) (Vec4 a' b' c' d') = Vec4 (a*a') (b*b') (c*c') (d*d')
>>>
>>>     vsum :: Vec4 ->  CFloat
>>>     {-# INLINE vsum #-}
>>>     vsum (Vec4 a b c d) = a+b+c+d
>>>
>>>     multList :: Int ->  Vector Vec4 ->  Vector Vec4
>>>     multList !count !src
>>>         | count<= 0    = src
>>>         | otherwise     = multList (count-1) $ V.map (\v ->  add (mult v m) a) src
>>>
>>>     main = do
>>>         print $ Data.Vector.Storable.sum
>>>               $ Data.Vector.Storable.map vsum
>>>               $ multList repCount
>>>               $ Data.Vector.Storable.replicate arraySize (Vec4 0 0 0 0)
>>>
>>>     repCount, arraySize :: Int
>>>     repCount = 10000
>>>     arraySize = 20000
>>>
>>>
>>>
>>> $ ghc-6.13.20100625 -fllvm -O2 --make A.hs
>>> [1 of 1] Compiling Main             ( A.hs, A.o )
>>> Linking A ...
>>> $ ./A
>>> zsh: segmentation fault  ./A
>>>
>>>
>>
> _______________________________________________
> Glasgow-haskell-bugs mailing list
> Glasgow-haskell-bugs at haskell.org
> http://www.haskell.org/mailman/listinfo/glasgow-haskell-bugs