Add and use snatToNum

See #72

src/CLaSH/Prelude/BlockRam/File.hs

@@ -98,7 +98,7 @@ import Data.Maybe                   (listToMaybe)
 import GHC.TypeLits                 (KnownNat)
 import Numeric                      (readInt)
 
-import CLaSH.Promoted.Nat    (SNat (..), pow2SNat, snatToInteger)
+import CLaSH.Promoted.Nat    (SNat (..), pow2SNat, snatToNum)
 import CLaSH.Sized.BitVector (BitVector)
 import CLaSH.Signal          (Signal)
 import CLaSH.Signal.Explicit (Signal', SClock, register', systemClock)
@@ -285,7 +285,7 @@ blockRamFile# :: KnownNat m
               -- clock cycle
 blockRamFile# clk sz file wr rd en din = register' clk (errorX "blockRamFile#: intial value undefined") dout
   where
-    szI  = fromInteger $ snatToInteger sz
+    szI  = snatToNum sz
     dout = runST $ do
       mem <- unsafeIOToST (initMem file)
       arr <- newListArray (0,szI-1) mem

src/CLaSH/Prelude/RAM.hs

@@ -43,7 +43,7 @@ import Data.Array.MArray.Safe (newListArray,readArray,writeArray)
 import Data.Array.ST.Safe     (STArray)
 import GHC.TypeLits           (KnownNat)
 
-import CLaSH.Promoted.Nat     (SNat (..), snatToInteger, pow2SNat)
+import CLaSH.Promoted.Nat     (SNat (..), snatToNum, pow2SNat)
 import CLaSH.Signal           (Signal)
 import CLaSH.Signal.Bundle    (bundle)
 import CLaSH.Signal.Explicit  (Signal', SClock, systemClock, unsafeSynchronizer)
@@ -146,7 +146,7 @@ asyncRam# :: SClock wclk       -- ^ 'Clock' to which to synchronise the write
           -> Signal' rclk a    -- ^ Value of the @RAM@ at address @r@
 asyncRam# wclk rclk sz wr rd en din = unsafeSynchronizer wclk rclk dout
   where
-    szI  = fromInteger $ snatToInteger sz
+    szI  = snatToNum sz
     rd'  = unsafeSynchronizer rclk wclk rd
     dout = runST $ do
       arr <- newListArray (0,szI-1) (replicate szI (errorX "asyncRam#: initial value undefined"))

src/CLaSH/Prelude/ROM/File.hs

@@ -93,7 +93,7 @@ import GHC.TypeLits                (KnownNat)
 import System.IO.Unsafe            (unsafePerformIO)
 
 import CLaSH.Prelude.BlockRam.File (initMem)
-import CLaSH.Promoted.Nat          (SNat (..), pow2SNat, snatToInteger)
+import CLaSH.Promoted.Nat          (SNat (..), pow2SNat, snatToNum)
 import CLaSH.Sized.BitVector       (BitVector)
 import CLaSH.Signal                (Signal)
 import CLaSH.Signal.Explicit       (Signal', SClock, register', systemClock)
@@ -166,15 +166,15 @@ asyncRomFile sz file = asyncRomFile# sz file . fromEnum
 -- >   where
 -- >     mem = unsafePerformIO (initMem file)
 -- >     content = listArray (0,szI-1) mem
--- >     szI     = fromInteger (snatToInteger sz)
+-- >     szI     = snatToNum sz
 --
 -- We write:
 --
 -- > asyncRomFile# sz file = (content !)
 -- >   where
 -- >     mem     = unsafePerformIO (initMem file)
 -- >     content = listArray (0,szI-1) mem
--- >     szI     = fromInteger (snatToInteger sz)
+-- >     szI     = snatToNum sz
 --
 -- Where instead of returning the BitVector defined by @(content ! rd)@, we
 -- return the function (thunk) @(content !)@.
@@ -232,7 +232,7 @@ asyncRomFile# sz file = (content !) -- Leave "(content !)" eta-reduced, see
   where                             -- Note [Eta-reduction and unsafePerformIO initMem]
     mem     = unsafePerformIO (initMem file)
     content = listArray (0,szI-1) mem
-    szI     = fromInteger (snatToInteger sz)
+    szI     = snatToNum sz
 
 {-# INLINE romFile #-}
 -- | A ROM with a synchronous read port, with space for @n@ elements
@@ -379,4 +379,4 @@ romFile# clk sz file rd = register' clk (errorX "romFile#: initial value undefin
   where
     mem     = unsafePerformIO (initMem file)
     content = listArray (0,szI-1) mem
-    szI     = fromInteger (snatToInteger sz)
+    szI     = snatToNum sz

src/CLaSH/Promoted/Nat.hs

@@ -24,7 +24,7 @@ module CLaSH.Promoted.Nat
   , withSNat
   , snat
     -- ** Conversion
-  , snatToInteger
+  , snatToInteger, snatToNum
     -- ** Arithmetic
   , addSNat, mulSNat, powSNat
     -- *** Partial
@@ -104,6 +104,11 @@ withSNat f = f SNat
 snatToInteger :: SNat n -> Integer
 snatToInteger p@SNat = natVal p
 
+-- | Reify the type-level 'Nat' @n@ to it's term-level 'Num'ber.
+snatToNum :: Num a => SNat n -> a
+snatToNum p@SNat = fromInteger (natVal p)
+{-# INLINE snatToNum #-}
+
 -- | Unary representation of a type-level natural
 --
 -- __NB__: Not synthesisable

src/CLaSH/Signal/Explicit.hs

@@ -37,7 +37,7 @@ where
 import Data.Maybe             (isJust, fromJust)
 import GHC.TypeLits           (KnownNat, KnownSymbol)
 
-import CLaSH.Promoted.Nat     (SNat (..), snatToInteger)
+import CLaSH.Promoted.Nat     (SNat (..), snatToNum)
 import CLaSH.Promoted.Symbol  (SSymbol (..))
 import CLaSH.Signal.Internal  (Signal' (..), Clock (..), SClock (..), register#,
                                regEn#)
@@ -243,8 +243,8 @@ unsafeSynchronizer :: SClock clk1 -- ^ 'Clock' of the incoming signal
                    -> Signal' clk2 a
 unsafeSynchronizer (SClock _ period1) (SClock _ period2) s = s'
   where
-    t1    = fromInteger (snatToInteger period1)
-    t2    = fromInteger (snatToInteger period2)
+    t1    = snatToNum period1
+    t2    = snatToNum period2
     s' | t1 < t2   = compress   t2 t1 s
        | t1 > t2   = oversample t1 t2 s
        | otherwise = same s

src/CLaSH/Sized/Internal/BitVector.hs

@@ -122,7 +122,7 @@ import Test.QuickCheck.Arbitrary  (Arbitrary (..), CoArbitrary (..),
 import CLaSH.Class.Num            (ExtendingNum (..), SaturatingNum (..),
                                    SaturationMode (..))
 import CLaSH.Class.Resize         (Resize (..))
-import CLaSH.Promoted.Nat         (SNat, snatToInteger)
+import CLaSH.Promoted.Nat         (SNat, snatToInteger, snatToNum)
 import CLaSH.XException           (ShowX (..), showsPrecXWith)
 
 import {-# SOURCE #-} qualified CLaSH.Sized.Vector         as V
@@ -452,7 +452,7 @@ slice# :: BitVector (m + 1 + i) -> SNat m -> SNat n -> BitVector (m + 1 - n)
 slice# (BV i) m n = BV (shiftR (i .&. mask) n')
   where
     m' = snatToInteger m
-    n' = fromInteger (snatToInteger n)
+    n' = snatToNum n
 
     mask = 2 ^ (m' + 1) - 1
 

src/CLaSH/Sized/RTree.hs

@@ -68,7 +68,7 @@ import Prelude                     hiding ((++), (!!))
 import Test.QuickCheck             (Arbitrary (..), CoArbitrary (..))
 
 import CLaSH.Class.BitPack         (BitPack (..))
-import CLaSH.Promoted.Nat          (SNat (..), UNat (..), pow2SNat, snatToInteger,
+import CLaSH.Promoted.Nat          (SNat (..), UNat (..), pow2SNat, snatToNum,
                                     subSNat, toUNat)
 import CLaSH.Promoted.Nat.Literals (d1)
 import CLaSH.Sized.Index           (Index)
@@ -371,7 +371,7 @@ tmap f = tdfold (Proxy @(MapTree b)) (LR . f) (\_ l r -> BR l r)
 tindices :: forall d . KnownNat d => RTree d (Index (2^d))
 tindices =
   tdfold (Proxy @(MapTree (Index (2^d)))) LR
-         (\s@SNat l r -> BR l (tmap (+(fromInteger (snatToInteger (pow2SNat s)))) r))
+         (\s@SNat l r -> BR l (tmap (+(snatToNum (pow2SNat s))) r))
          (treplicate SNat 0)
 
 data V2TTree (a :: *) (f :: TyFun Nat *) :: *