Add non determinism probability to generation

4 files changed, 64 insertions, 25 deletions

diff --git a/default.nix b/default.nix
index e034ece..db81294 100644
--- a/default.nix
+++ b/default.nix
@@ -9,7 +9,7 @@
 }:
 mkDerivation {
   pname = "verifuzz";
-  version = "0.3.0.0";
+  version = "0.3.1.0";
   src = ./.;
   isLibrary = true;
   isExecutable = true;
diff --git a/src/VeriFuzz/Config.hs b/src/VeriFuzz/Config.hs
index dab854b..8705f7c 100644
--- a/src/VeriFuzz/Config.hs
+++ b/src/VeriFuzz/Config.hs
@@ -69,6 +69,8 @@ module VeriFuzz.Config
     , propModDepth
     , propMaxModules
     , propCombine
+    , propDeterminism
+    , propNonDeterminism
     , parseConfigFile
     , parseConfig
     , encodeConfig
@@ -192,14 +194,36 @@ data Probability = Probability { _probModItem :: {-# UNPACK #-} !ProbModItem
                                }
                  deriving (Eq, Show)
 
-data ConfProperty = ConfProperty { _propSize         :: {-# UNPACK #-} !Int
-                                 , _propSeed         :: !(Maybe Seed)
-                                 , _propStmntDepth   :: {-# UNPACK #-} !Int
-                                 , _propModDepth     :: {-# UNPACK #-} !Int
-                                 , _propMaxModules   :: {-# UNPACK #-} !Int
-                                 , _propSampleMethod :: !Text
-                                 , _propSampleSize   :: {-# UNPACK #-} !Int
-                                 , _propCombine      :: !Bool
+data ConfProperty = ConfProperty { _propSize           :: {-# UNPACK #-} !Int
+                                 -- ^ The size of the generated Verilog.
+                                 , _propSeed           :: !(Maybe Seed)
+                                 -- ^ A possible seed that could be used to
+                                 -- generate the same Verilog.
+                                 , _propStmntDepth     :: {-# UNPACK #-} !Int
+                                 -- ^ The maximum statement depth that should be
+                                 -- reached.
+                                 , _propModDepth       :: {-# UNPACK #-} !Int
+                                 -- ^ The maximium module depth that should be
+                                 -- reached.
+                                 , _propMaxModules     :: {-# UNPACK #-} !Int
+                                 -- ^ The maximum number of modules that are
+                                 -- allowed to be created at each level.
+                                 , _propSampleMethod   :: !Text
+                                 -- ^ The sampling method that should be used to
+                                 -- generate specific distributions of random
+                                 -- programs.
+                                 , _propSampleSize     :: {-# UNPACK #-} !Int
+                                 -- ^ The number of samples to take for the
+                                 -- sampling method.
+                                 , _propCombine        :: !Bool
+                                 -- ^ If the output should be combined into one
+                                 -- bit or not.
+                                 , _propNonDeterminism :: {-# UNPACK #-} !Int
+                                 -- ^ The frequency at which nondeterminism
+                                 -- should be generated.
+                                 , _propDeterminism    :: {-# UNPACK #-} !Int
+                                 -- ^ The frequency at which determinism should
+                                 -- be generated.
                                  }
                   deriving (Eq, Show)
 
@@ -267,7 +291,7 @@ defaultConfig :: Config
 defaultConfig = Config
     (Info (pack $(gitHash)) (pack $ showVersion version))
     (Probability defModItem defStmnt defExpr)
-    (ConfProperty 20 Nothing 3 2 5 "random" 10 False)
+    (ConfProperty 20 Nothing 3 2 5 "random" 10 False 0 1)
     []
     [fromYosys defaultYosys, fromVivado defaultVivado]
   where
@@ -388,6 +412,10 @@ propCodec =
         <*> defaultValue (defProp propCombine)
                          (Toml.bool (twoKey "output" "combine"))
         .=  _propCombine
+        <*> defaultValue (defProp propNonDeterminism) (Toml.int "nondeterminism")
+        .=  _propNonDeterminism
+        <*> defaultValue (defProp propDeterminism) (Toml.int "determinism")
+        .=  _propDeterminism
     where defProp i = defaultConfig ^. configProperty . i
 
 simulator :: TomlCodec SimDescription
diff --git a/src/VeriFuzz/Verilog/Gen.hs b/src/VeriFuzz/Verilog/Gen.hs
index 6ba79ea..e037b67 100644
--- a/src/VeriFuzz/Verilog/Gen.hs
+++ b/src/VeriFuzz/Verilog/Gen.hs
@@ -54,6 +54,7 @@ data Context = Context { _variables   :: [Port]
                        , _nameCounter :: {-# UNPACK #-} !Int
                        , _stmntDepth  :: {-# UNPACK #-} !Int
                        , _modDepth    :: {-# UNPACK #-} !Int
+                       , _determinism :: !Bool
                        }
 
 makeLenses ''Context
@@ -312,16 +313,6 @@ conditional = do
     nameCounter .= max nc' nc''
     return $ CondStmnt expr (Just tstat) (Just fstat)
 
---constToExpr :: ConstExpr -> Expr
---constToExpr (ConstNum s n    ) = Number s n
---constToExpr (ParamId     i   ) = Id i
---constToExpr (ConstConcat c   ) = Concat $ constToExpr <$> c
---constToExpr (ConstUnOp u p   ) = UnOp u (constToExpr p)
---constToExpr (ConstBinOp a b c) = BinOp (constToExpr a) b (constToExpr c)
---constToExpr (ConstCond a b c) =
---    Cond (constToExpr a) (constToExpr b) (constToExpr c)
---constToExpr (ConstStr s) = Str s
-
 forLoop :: StateGen Statement
 forLoop = do
     num <- Hog.int (Hog.linear 0 20)
@@ -435,21 +426,27 @@ modInst = do
 -- | Generate a random module item.
 modItem :: StateGen ModItem
 modItem = do
-    prob    <- askProbability
+    conf    <- lift ask
+    let prob = conf ^. configProbability
     context <- get
     let defProb i = prob ^. probModItem . i
+    det <- Hog.frequency [ (conf ^. configProperty . propDeterminism, return True)
+                         , (conf ^. configProperty . propNonDeterminism, return False) ]
+    determinism .= det
     Hog.frequency
         [ (defProb probModItemAssign   , ModCA <$> contAssign)
         , (defProb probModItemSeqAlways, alwaysSeq)
         , ( if context ^. modDepth > 0 then defProb probModItemInst else 0
-          , modInst
-          )
+          , modInst )
         ]
 
+-- | Either return the 'Identifier' that was passed to it, or generate a new
+-- 'Identifier' based on the current 'nameCounter'.
 moduleName :: Maybe Identifier -> StateGen Identifier
 moduleName (Just t) = return t
 moduleName Nothing  = makeIdentifier "module"
 
+-- | Generate a random 'ConstExpr' by using the current context of 'Parameters'.
 constExpr :: StateGen ConstExpr
 constExpr = do
     prob    <- askProbability
@@ -457,6 +454,9 @@ constExpr = do
     gen . Hog.sized $ constExprWithContext (context ^. parameters)
                                            (prob ^. probExpr)
 
+-- | Generate a random 'Parameter' and assign it to a constant expression which
+-- it will be initialised to. The assumption is that this constant expression
+-- should always be able to be evaluated with the current context of parameters.
 parameter :: StateGen Parameter
 parameter = do
     ident <- makeIdentifier "param"
@@ -470,11 +470,14 @@ evalRange :: [Parameter] -> Int -> Range -> Range
 evalRange ps n (Range l r) = Range (eval l) (eval r)
     where eval = ConstNum . cata (evaluateConst ps) . resize n
 
+-- | Calculate a range to an int by maybe resizing the ranges to a value.
 calcRange :: [Parameter] -> Maybe Int -> Range -> Int
 calcRange ps i (Range l r) = eval l - eval r + 1
   where
     eval a = fromIntegral . cata (evaluateConst ps) $ maybe a (`resize` a) i
 
+-- | Filter out a port based on it's name instead of equality of the ports. This
+-- is because the ports might not be equal if the sizes are being updated.
 identElem :: Port -> [Port] -> Bool
 identElem p = elem (p ^. portName) . toListOf (traverse . portName)
 
@@ -492,7 +495,7 @@ moduleDef top = do
     config   <- lift ask
     let (newPorts, local) = partition (`identElem` portList) $ _variables context
     let
-        size =
+         size =
             evalRange (_parameters context) 32
                 .   sum
                 $   local
@@ -518,15 +521,21 @@ procedural top config = do
     return . Verilog $ mainMod : st ^. modules
   where
     context =
-        Context [] [] [] 0 (confProp propStmntDepth) $ confProp propModDepth
+        Context [] [] [] 0 (confProp propStmntDepth) (confProp propModDepth) True
     num = fromIntegral $ confProp propSize
     confProp i = config ^. configProperty . i
 
+-- | Samples the 'Gen' directly to generate random 'Verilog' using the 'T.Text' as
+-- the name of the main module and the configuration 'Config' to influence the
+-- generation.
 proceduralIO :: T.Text -> Config -> IO Verilog
 proceduralIO t = Hog.sample . procedural t
 
+-- | Given a 'T.Text' and a 'Config' will generate a 'SourceInfo' which has the
+-- top module set to the right name.
 proceduralSrc :: T.Text -> Config -> Gen SourceInfo
 proceduralSrc t c = SourceInfo t <$> procedural t c
 
+-- | Sampled and wrapped into a 'SourceInfo' with the given top module name.
 proceduralSrcIO :: T.Text -> Config -> IO SourceInfo
 proceduralSrcIO t c = SourceInfo t <$> proceduralIO t c
diff --git a/verifuzz.cabal b/verifuzz.cabal
index aa64717..b939034 100644
--- a/verifuzz.cabal
+++ b/verifuzz.cabal
@@ -62,6 +62,8 @@ library
                  , VeriFuzz.Verilog.Quote
                  , VeriFuzz.Verilog.Token
   build-depends: base >=4.7 && <5
+               -- Cannot upgrade to 1.0 because of missing MonadGen instance for
+               -- StateT.
                , hedgehog >= 0.5.3 && <0.7
                , fgl >=5.6 && <5.8
                , fgl-visualize >=0.1 && <0.2