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--- $Id: LUTGates.hs#2 2010/09/21 13:51:11 REDMOND\\satnams $
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module Lava.LUTGates
where
import Control.Monad.State
import Lava.Netlist

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unaryLUT :: (Bool -> Bool) -> String -> Bit -> Out Bit
unaryLUT gateOperation comment i0
  = do state <- get
       let insts = instances state
           oNet = netCount state
           instNr = instCount state
           placement = if layoutNesting state > 0 then
                         At (0,0)
                       else
                         Unplaced
           cSize = if layoutNesting state > 0 then
                     Just (1,1)
                   else
                     Nothing
           newInst = Instance (Lut1 opBits i0 oNet comment) 
                               "lut1" instNr placement cSize
       put (state{instances = newInst:insts, 
                  netCount = oNet+1, 
                  instCount = instNr +1})
       return oNet 
    where
    opBits = map boolToInt [gateOperation False, gateOperation True]

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boolToInt :: Bool -> Int
boolToInt False = 0
boolToInt True  = 1

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binaryLUT :: (Bool -> Bool -> Bool) -> String -> (Bit, Bit) -> Out Bit
binaryLUT gateOperation comment (i0, i1)
  = do state <- get
       let insts = instances state
           oNet = netCount state
           instNr = instCount state
           placement = if layoutNesting state > 0 then
                         At (0, 0)
                       else
                         Unplaced
           cSize = if layoutNesting state > 0 then
                     Just (1,1)
                   else
                     Nothing
           newInst = Instance (Lut2 opBits i0 i1 oNet comment) 
                               "lut2" instNr placement cSize
       put (state{instances = newInst:insts, 
                  netCount = oNet+1, 
                  instCount = instNr +1})
       return oNet
    where
    opBits = map boolToInt [gateOperation False False,
                            gateOperation True  False,
                            gateOperation False True,
                            gateOperation True  True]

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