4 files changed, 245 insertions, 0 deletions
diff --git a/src/Verismith/Circuit/Base.hs b/src/Verismith/Circuit/Base.hs
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+{-|
+Module      : Verismith.Circuit.Base
+Description : Base types for the circuit module.
+Copyright   : (c) 2019, Yann Herklotz Grave
+License     : GPL-3
+Maintainer  : yann [at] yannherklotz [dot] com
+Stability   : experimental
+Portability : POSIX
+
+Base types for the circuit module.
+-}
+
+module Verismith.Circuit.Base
+    ( Gate(..)
+    , Circuit(..)
+    , CNode(..)
+    , CEdge(..)
+    )
+where
+
+import           Data.Graph.Inductive (Gr, LEdge, LNode)
+import           System.Random
+
+-- | The types for all the gates.
+data Gate = And
+          | Or
+          | Xor
+          deriving (Show, Eq, Enum, Bounded, Ord)
+
+-- | Newtype for the Circuit which implements a Graph from fgl.
+newtype Circuit = Circuit { getCircuit :: Gr Gate () }
+
+-- | Newtype for a node in the circuit, which is an 'LNode Gate'.
+newtype CNode = CNode { getCNode :: LNode Gate }
+
+-- | Newtype for a named edge which is empty, as it does not need a label.
+newtype CEdge = CEdge { getCEdge :: LEdge () }
+
+instance Random Gate where
+  randomR (a, b) g =
+    case randomR (fromEnum a, fromEnum b) g of
+      (x, g') -> (toEnum x, g')
+
+  random = randomR (minBound, maxBound)
diff --git a/src/Verismith/Circuit/Gen.hs b/src/Verismith/Circuit/Gen.hs
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+{-|
+Module      : Verilog.Circuit.Gen
+Description : Generate verilog from circuit.
+Copyright   : (c) 2019, Yann Herklotz Grave
+License     : GPL-3
+Maintainer  : yann [at] yannherklotz [dot] com
+Stability   : experimental
+Portability : POSIX
+
+Generate verilog from circuit.
+-}
+
+module Verismith.Circuit.Gen
+    ( generateAST
+    )
+where
+
+import           Data.Graph.Inductive       (LNode, Node)
+import qualified Data.Graph.Inductive       as G
+import           Data.Maybe                 (catMaybes)
+import           Verismith.Circuit.Base
+import           Verismith.Circuit.Internal
+import           Verismith.Verilog.AST
+import           Verismith.Verilog.Mutate
+
+-- | Converts a 'CNode' to an 'Identifier'.
+frNode :: Node -> Identifier
+frNode = Identifier . fromNode
+
+-- | Converts a 'Gate' to a 'BinaryOperator', which should be a bijective
+-- mapping.
+fromGate :: Gate -> BinaryOperator
+fromGate And = BinAnd
+fromGate Or  = BinOr
+fromGate Xor = BinXor
+
+inputsC :: Circuit -> [Node]
+inputsC c = inputs (getCircuit c)
+
+genPortsAST :: (Circuit -> [Node]) -> Circuit -> [Port]
+genPortsAST f c = port . frNode <$> f c where port = Port Wire False 4
+
+-- | Generates the nested expression AST, so that it can then generate the
+-- assignment expressions.
+genAssignExpr :: Gate -> [Node] -> Maybe Expr
+genAssignExpr _ []       = Nothing
+genAssignExpr _ [n     ] = Just . Id $ frNode n
+genAssignExpr g (n : ns) = BinOp wire oper <$> genAssignExpr g ns
+  where
+    wire = Id $ frNode n
+    oper = fromGate g
+
+-- | Generate the continuous assignment AST for a particular node. If it does
+-- not have any nodes that link to it then return 'Nothing', as that means that
+-- the assignment will just be empty.
+genContAssignAST :: Circuit -> LNode Gate -> Maybe ModItem
+genContAssignAST c (n, g) = ModCA . ContAssign name <$> genAssignExpr g nodes
+  where
+    gr    = getCircuit c
+    nodes = G.pre gr n
+    name  = frNode n
+
+genAssignAST :: Circuit -> [ModItem]
+genAssignAST c = catMaybes $ genContAssignAST c <$> nodes
+  where
+    gr    = getCircuit c
+    nodes = G.labNodes gr
+
+genModuleDeclAST :: Circuit -> ModDecl
+genModuleDeclAST c = ModDecl i output ports (combineAssigns yPort a) []
+  where
+    i      = Identifier "gen_module"
+    ports  = genPortsAST inputsC c
+    output = []
+    a      = genAssignAST c
+    yPort  = Port Wire False 90 "y"
+
+generateAST :: Circuit -> Verilog
+generateAST c = Verilog [genModuleDeclAST c]
diff --git a/src/Verismith/Circuit/Internal.hs b/src/Verismith/Circuit/Internal.hs
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+{-|
+Module      : Verismith.Circuit.Internal
+Description : Internal helpers for generation.
+Copyright   : (c) 2018-2019, Yann Herklotz
+License     : BSD-3
+Maintainer  : yann [at] yannherklotz [dot] com
+Stability   : experimental
+Portability : POSIX
+
+Internal helpers for generation.
+-}
+
+module Verismith.Circuit.Internal
+    ( fromNode
+    , filterGr
+    , only
+    , inputs
+    , outputs
+    )
+where
+
+import           Data.Graph.Inductive (Graph, Node)
+import qualified Data.Graph.Inductive as G
+import qualified Data.Text            as T
+
+-- | Convert an integer into a label.
+--
+-- >>> fromNode 5
+-- "w5"
+fromNode :: Int -> T.Text
+fromNode node = T.pack $ "w" <> show node
+
+-- | General function which runs 'filter' over a graph.
+filterGr :: (Graph gr) => gr n e -> (Node -> Bool) -> [Node]
+filterGr graph f = filter f $ G.nodes graph
+
+-- | Takes two functions that return an 'Int', and compares there results to 0
+-- and not 0 respectively. This result is returned.
+only
+    :: (Graph gr)
+    => gr n e
+    -> (gr n e -> Node -> Int)
+    -> (gr n e -> Node -> Int)
+    -> Node
+    -> Bool
+only graph fun1 fun2 n = fun1 graph n == 0 && fun2 graph n /= 0
+
+-- | Returns all the input nodes to a graph, which means nodes that do not have
+-- an input themselves.
+inputs :: (Graph gr) => gr n e -> [Node]
+inputs graph = filterGr graph $ only graph G.indeg G.outdeg
+
+-- | Returns all the output nodes to a graph, similar to the 'inputs' function.
+outputs :: (Graph gr) => gr n e -> [Node]
+outputs graph = filterGr graph $ only graph G.outdeg G.indeg
diff --git a/src/Verismith/Circuit/Random.hs b/src/Verismith/Circuit/Random.hs
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+++ b/src/Verismith/Circuit/Random.hs
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+{-|
+Module      : Verismith.Circuit.Random
+Description : Random generation for DAG
+Copyright   : (c) 2018-2019, Yann Herklotz
+License     : BSD-3
+Maintainer  : yann [at] yannherklotz [dot] com
+Stability   : experimental
+Portability : POSIX
+
+Define the random generation for the directed acyclic graph.
+-}
+
+module Verismith.Circuit.Random
+    ( rDups
+    , rDupsCirc
+    , randomDAG
+    , genRandomDAG
+    )
+where
+
+import           Data.Graph.Inductive              (Context)
+import qualified Data.Graph.Inductive              as G
+import           Data.Graph.Inductive.PatriciaTree (Gr)
+import           Data.List                         (nub)
+import           Hedgehog                          (Gen)
+import qualified Hedgehog.Gen                      as Hog
+import qualified Hedgehog.Range                    as Hog
+import           Verismith.Circuit.Base
+
+dupFolder :: (Eq a, Eq b) => Context a b -> [Context a b] -> [Context a b]
+dupFolder cont ns = unique cont : ns
+    where unique (a, b, c, d) = (nub a, b, c, nub d)
+
+-- | Remove duplicates.
+rDups :: (Eq a, Eq b) => Gr a b -> Gr a b
+rDups g = G.buildGr $ G.ufold dupFolder [] g
+
+-- | Remove duplicates.
+rDupsCirc :: Circuit -> Circuit
+rDupsCirc = Circuit . rDups . getCircuit
+
+-- | Gen instance to create an arbitrary edge, where the edges are limited by
+-- `n` that is passed to it.
+arbitraryEdge :: Hog.Size -> Gen CEdge
+arbitraryEdge n = do
+    x <- with $ \a -> a < n && a > 0 && a /= n - 1
+    y <- with $ \a -> x < a && a < n && a > 0
+    return $ CEdge (fromIntegral x, fromIntegral y, ())
+  where
+    with = flip Hog.filter $ fromIntegral <$> Hog.resize
+        n
+        (Hog.int (Hog.linear 0 100))
+
+-- | Gen instance for a random acyclic DAG.
+randomDAG :: Gen Circuit -- ^ The generated graph. It uses Arbitrary to generate
+                         -- random instances of each node
+randomDAG = do
+    list <- Hog.list (Hog.linear 1 100) $ Hog.enum minBound maxBound
+    l    <- Hog.list (Hog.linear 10 1000) aE
+    return . Circuit $ G.mkGraph (nodes list) l
+  where
+    nodes l = zip [0 .. length l - 1] l
+    aE = getCEdge <$> Hog.sized arbitraryEdge
+
+-- | Generate a random acyclic DAG with an IO instance.
+genRandomDAG :: IO Circuit
+genRandomDAG = Hog.sample randomDAG