~thestr4ng3r/shida

02f6b8e77686be6898088519dba2bc2d1df31c3c — Florian Märkl 4 years ago
Initial Public Release
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A  => LICENSE +674 -0
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                    GNU GENERAL PUBLIC LICENSE
                       Version 3, 29 June 2007

 Copyright (C) 2007 Free Software Foundation, Inc. <https://fsf.org/>
 Everyone is permitted to copy and distribute verbatim copies
 of this license document, but changing it is not allowed.

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Also add information on how to contact you by electronic and paper mail.

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The hypothetical commands `show w' and `show c' should show the appropriate
parts of the General Public License.  Of course, your program's commands
might be different; for a GUI interface, you would use an "about box".

  You should also get your employer (if you work as a programmer) or school,
if any, to sign a "copyright disclaimer" for the program, if necessary.
For more information on this, and how to apply and follow the GNU GPL, see
<https://www.gnu.org/licenses/>.

  The GNU General Public License does not permit incorporating your program
into proprietary programs.  If your program is a subroutine library, you
may consider it more useful to permit linking proprietary applications with
the library.  If this is what you want to do, use the GNU Lesser General
Public License instead of this License.  But first, please read
<https://www.gnu.org/licenses/why-not-lgpl.html>.

A  => README.md +64 -0
@@ 1,64 @@
# 羊歯 Shida

Shida is an experimental SMT solver for Bit Vectors written in Haskell that has
been developed alongside a paper on the same topic (available in [doc](doc))
for the seminar [Automated Reasoning](https://www21.in.tum.de/teaching/sar/SS20/) at TUM.

**Disclaimer**: If you are looking for an efficient, production quality solver,
do not use this. Use something like [Z3](https://github.com/Z3Prover/z3) instead.

## Usage

Build:
```
stack build
```

Run all tests:
```
stack test
```

The solver can be used conveniently in ghci, for example:
```Haskell
$ stack repl
λ> f = Atom $ (uVar 8 "a" :-: uConst (13::Word8)) :==: uConst (29::Word8)
λ> f
((a - 0b00001101) = 0b00011101)
λ> solve f
Solution (fromList [("a",0b00101010)])
```

More examples for formulas can be found in [test/SolveTest.hs](test/SolveTest.hs).

The most important solving functions are:

```Haskell
-- |Solve to a single solution
solve :: Formula -> SolveResult Solution

-- |Solve to all solutions as a lazy list
solveAll :: Formula -> SolveResult [Solution]

-- |Solve incrementally to a single solution
-- This can be significantly faster or slower than solve depending on the
-- formula, see the paper for more info.
solveIncremental :: Int -> Formula -> SolveResult Solution
```

## About

Created by Florian Märkl.

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <https://www.gnu.org/licenses/>.

A  => Setup.hs +2 -0
@@ 1,2 @@
import Distribution.Simple
main = defaultMain

A  => app/Main.hs +117 -0
@@ 1,117 @@
module Main where

import Data.Word
import Data.Int
--import Data.Maybe
import Data.Bits
import Data.Either

import qualified BitVectorValue as BV
import Common
import Formula
import Flattening
import Solve

example0 = (Atom $ uConst (42::Word8) :==: uVar 8 "a")
           :&&:
           (Atom $ uVar 8 "b" :==: (uVar 8 "a" :^: uConst (123::Word8)))

example1 = Atom $ uVar 8 "a" :==: (uConst (13::Word8) :+: uConst (29::Word8))

bconjunction :: [Formula] -> Formula
bconjunction [x, y] = And x y
bconjunction (x : xs) = And x $ bconjunction xs
bconjunction [] = undefined

example2 :: Word8 -> Formula
example2 x = bconjunction $ map (\i ->
            if ((x `shiftR` i) .&. 1) /= 0 then
                Atom $ Pick (fromIntegral i) (uVar 8 "a")
            else
                Not $ Atom $ Pick (fromIntegral i) (uVar 8 "a")
        ) [0..7]

example3 :: Int8 -> Formula
example3 x = bconjunction $
                         (if x == -128 then [] else [
                             Atom $ sConst (x-1) :<: sVar 8 "a"
                         ]) ++ (if x == 127 then [] else [
                             Atom $ sVar 8 "a" :<: sConst (x+1)
                         ])

exampleShift :: Word8 -> Word8 -> Formula
exampleShift x s =
    Atom $ uVar 8 "a" :==: (uConst x :>>: Const Unsigned (BV.slice (BV.toBitVector s) 0 3))

exampleMult :: Word8 -> Word8 -> Formula
exampleMult l r =
    Atom $ uVar 8 "a" :==: (uConst l :*: uConst r)

exampleDiv :: Int8 -> Int8 -> Formula
exampleDiv l r =
    Atom $ sVar 8 "a" :==: (sConst l :/: sConst r)

exampleMod :: Int8 -> Int8 -> Formula
exampleMod l r =
    Atom $ sVar 8 "a" :==: (sConst l :%: sConst r)

exampleConcat :: Word8 -> Word8 -> Formula
exampleConcat l r =
    Atom $ sVar 16 "a" :==: Concat Signed (uConst l) (uConst r)

exampleTernary :: Bool -> Word8 -> Word8 -> Formula
exampleTernary c a b = Atom $ uVar 8 "a" :==: Ternary (BConst c) (uConst a) (uConst b)

exampleHardUnsat0 :: Size -> Formula
exampleHardUnsat0 sz = Atom ((uVar sz "a" :*: uVar sz "b") :==: uVar sz "c")
                :&&: Not (Atom ((uVar sz "b" :*: uVar sz "a") :==: uVar sz "c"))
                :&&: Atom (uVar sz "x" :<: uVar sz "y")
                :&&: Atom (uVar sz "y" :<: uVar sz "x")

exampleHardUnsat1 :: Size -> Formula
exampleHardUnsat1 sz = Atom ((uVar sz "a" :*: uVar sz "b") :==: uVar sz "c")
                :&&: Atom ((uVar sz "b" :*: uVar sz "a") :==: uVar sz "c")
                :&&: Atom (uVar sz "x" :<: uVar sz "y")
                :&&: Atom (uVar sz "y" :<: uVar sz "x")

exampleSat1 :: Size -> Formula
exampleSat1 sz = Atom (uVar sz "a" :==: Const Unsigned (BV.replicate sz False))
                    :&&: Not (     Not (Atom $ (uVar sz "b" :*: uVar sz "c") :<: uVar sz "d")
                              :&&: Not (Atom $ uVar sz "d" :<: (uVar sz "b" :*: uVar sz "c")))

main :: IO ()
main = do
    let x = 1::Int8
    let y = -1::Int8
    let f = Atom $ sVar 8 "a" :==: (sConst x :*: sConst y)
    putStrLn $ "Solve: " ++ show f
    putStrLn "-- Flattened:"
    let flat = fromRight undefined $ flatten f
    print flat
    putStrLn "-- Final Result:"
    print $ solve f

--main :: IO ()
--main = do
--    let x = -1::Int8
--    let y = 2::Int8
--    --print $ flatten $ exampleDiv x y
--    putStrLn $ "Solve: " ++ show x ++ " / " ++ show y
--    putStrLn $ "Result: " ++ show (solve $ exampleDiv x y)
--    putStrLn $ "Remain: " ++ show (solve $ exampleMod x y)

--main :: IO ()
--main = do
--    let x = 1
--    let f = exampleHardUnsat1 64 -- example1
--    putStrLn $ "Solve: " ++ show f
--    --putStrLn ""
--    --putStrLn "-- Flattened:"
--    --let flat = fromRight undefined $ flatten f
--    --print flat
--    --putStrLn "-- Propositional:"
--    --print $ propositional flat
--    putStrLn ""
--    putStrLn "-- Final Result:"
--    print $ solveIncremental 1 f
--    --print $ solve f

A  => doc/crackme/.gitignore +2 -0
@@ 1,2 @@
*.c
Makefile

A  => doc/crackme/crackme +0 -0
A  => doc/crackme/solve.hs +54 -0
@@ 1,54 @@
import Common
import Formula
import Solve
import qualified BitVectorValue as BV

import Data.Maybe
import Data.Word
import qualified Data.Map as Map
import qualified Data.ByteString as B

import Control.Monad

hash :: [Word8]
hash = [0xa2, 0x35, 0xa3, 0x0f, 0x1c, 0xd0, 0x0e, 0x9e]

-- |Combine a list of formulas into a single formula one using And
conjunction :: [Formula] -> Formula
conjunction [a]        = a
conjunction (a : as)   = And a (conjunction as)
conjunction _          = undefined

-- |Variable name for the i-th character in the password
pwCharVarName :: Int -> String
pwCharVarName i = "pw[" ++ show i ++ "]"

-- |Term for the i-th character in the password
pwChar :: Int -> Term
pwChar = uVar 8 . pwCharVarName 

formula :: Formula
formula =
    conjunction $
        map (\i ->
            let a = pwChar $ i
                b = pwChar $ (i + 1) `rem` 8
                c = pwChar $ (i + 2) `rem` 8
                d = pwChar $ (i + 3) `rem` 8
                shiftPlus = Slice Unsigned 0 3 (b :+: c)
                shiftMinus = Slice Unsigned 0 3 (b :-: c)
                eight = Const Unsigned $ BV.pack [False, False, False] -- Only 3 bits, overflow on purpose for 8 - x
                term = ((a :<<: shiftPlus) :|: (a :>>: (eight :-: shiftMinus))) :-: d
            in (Atom $ term :==: uConst (hash!!i)) :&&: (Not $ Atom $ Pick 7 a)
        ) [0..7]

main :: IO ()
main =
    case solveAll formula of
    Solution s ->
        forM_ s (\s ->
            putStrLn $ toEnum <$> fromIntegral <$> map (\i ->
                           let bv = s Map.! (pwCharVarName i) in
                           (fromJust (BV.fromBitVector bv))::Word8) [0..7]
            )
    res -> print res

A  => doc/paper.pdf +0 -0
A  => doc/slides.pdf +0 -0
A  => shida.cabal +62 -0
@@ 1,62 @@
cabal-version: 1.12

name:           shida
version:        0.1.0.0
author:         Florian Märkl
license:        GPL-3
license-file:   LICENSE
build-type:     Simple
extra-source-files:
    README.md

source-repository head
  type: git
  location: https://github.com/thestr4ng3r/shida

library
  exposed-modules:
      Common,
      BitVectorValue
      Formula
      Propositional
      Flattening
      Solve
      MiniSat
  hs-source-dirs:
      src
  build-depends:
      base >=4.7 && <5,
      bytestring,
      containers,
      mtl,
      transformers,
      minisat-solver
  default-language: Haskell2010
  ghc-options: -W

executable shida-exe
  main-is: Main.hs
  hs-source-dirs:
      app
  ghc-options: -threaded -rtsopts -with-rtsopts=-N
  build-depends:
      base >=4.7 && <5,
      shida,
      minisat-solver
  default-language: Haskell2010

test-suite shida-test
  type: exitcode-stdio-1.0
  main-is: Spec.hs
  other-modules:
      BitVectorValueTest
      SolveTest
  hs-source-dirs:
      test
  ghc-options: -threaded -rtsopts -with-rtsopts=-N
  build-depends:
      base >=4.7 && <5,
      QuickCheck,
      shida,
      containers
  default-language: Haskell2010

A  => src/BitVectorValue.hs +135 -0
@@ 1,135 @@
module BitVectorValue (
    Size,
    BoundsException,
    BitVectorValue,
    index,
    replicate,
    length,
    unpack,
    pack,
    ToBitVector,
    toBitVector,
    FromBitVector,
    fromBitVector,
    slice
) where


import qualified Prelude as P
import Prelude hiding (length,replicate)

import Data.Word
import Data.Int
import Data.Bits
import qualified Data.ByteString as B

import Control.Exception
import Data.Function ((&))

import Common

data BoundsException = BoundsException deriving (Show)
instance Exception BoundsException

data BitVectorValue = BitVectorValue Size B.ByteString

instance Eq BitVectorValue where
    (==) (BitVectorValue lsz ldat) (BitVectorValue rsz rdat) =
        lsz == rsz && foldl (\acc i -> acc && (index (BitVectorValue lsz ldat) i == index (BitVectorValue rsz rdat) i)) True [0..lsz-1]

compareBits :: Size -> BitVectorValue -> BitVectorValue -> Ordering
compareBits 0 a b = compare (index a 0) (index b 0)
compareBits i a b =
    let r = compare (index a i) (index b i) in
    if r == EQ then
        compareBits (i-1) a b
    else
        r

instance Ord BitVectorValue where
    compare a b =
        let szc = compare (length a) (length b) in
        if szc == EQ then
            compareBits (length a - 1) a b
        else
            szc

instance Show BitVectorValue where
    show (BitVectorValue sz dat) =
        foldl (\acc i -> acc ++ (if index (BitVectorValue sz dat) i then "1" else "0")) "0b" $ reverse [0..sz-1]

index :: BitVectorValue -> Size -> Bool
index (BitVectorValue sz dat) i =
    if i >= sz then
        throw BoundsException
    else
        let byte = B.index dat $ fromIntegral $ i `shiftR` 3
            biti = i .&. 0x7 in
        ((byte `shiftR` fromIntegral biti) .&. 1) == 1

replicate :: Size -> Bool -> BitVectorValue
replicate sz v = BitVectorValue sz $ B.replicate (fromIntegral ((sz + 7) `shiftR` 3)) $ if v then 0xff else 0

length :: BitVectorValue -> Size
length (BitVectorValue sz _) = sz

unpack :: BitVectorValue -> [Bool]
unpack bv = map (index bv) [0..length bv - 1]

packByte :: Bool -> Bool -> Bool -> Bool -> Bool -> Bool -> Bool -> Bool -> Word8
packByte b0 b1 b2 b3 b4 b5 b6 b7 = foldr (\b acc -> (acc `shiftL` 1) .|. (if b then 1 else 0)) 0 [b0, b1, b2, b3, b4, b5, b6, b7]

packBytes :: [Bool] -> [Word8]
packBytes (b0 : b1 : b2 : b3 : b4 : b5 : b6 : b7 : bs) = packByte b0 b1 b2 b3 b4 b5 b6 b7 : packBytes bs
packBytes [b0, b1, b2, b3, b4, b5, b6] = [packByte b0 b1 b2 b3 b4 b5 b6 False]
packBytes [b0, b1, b2, b3, b4, b5] = [packByte b0 b1 b2 b3 b4 b5 False False]
packBytes [b0, b1, b2, b3, b4] = [packByte b0 b1 b2 b3 b4 False False False]
packBytes [b0, b1, b2, b3] = [packByte b0 b1 b2 b3 False False False False]
packBytes [b0, b1, b2] = [packByte b0 b1 b2 False False False False False]
packBytes [b0, b1] = [packByte b0 b1 False False False False False False]
packBytes [b0] = [packByte b0 False False False False False False False]
packBytes [] = []

pack :: [Bool] -> BitVectorValue
pack bits = BitVectorValue (fromIntegral $ P.length bits) $ B.pack $ packBytes bits

class ToBitVector a where
    toBitVector :: a -> BitVectorValue

instance ToBitVector Word8 where
    toBitVector w = BitVectorValue 8 $ B.singleton w

instance ToBitVector Word16 where
    toBitVector w = BitVectorValue 16 $ B.pack $ map fromIntegral [w .&. 0xff,
                                                                 (w `shiftR` 8) .&. 0xff]

instance ToBitVector Word32 where
    toBitVector w = BitVectorValue 32 $ B.pack $ map fromIntegral [w .&. 0xff,
                                                                 (w `shiftR` 8) .&. 0xff,
                                                                 (w `shiftR` 0x10) .&. 0xff,
                                                                 (w `shiftR` 0x18) .&. 0xff]
instance ToBitVector Word64 where
    toBitVector w = BitVectorValue 64 $ B.pack $ map fromIntegral [w .&. 0xff,
                                                                 (w `shiftR` 8) .&. 0xff,
                                                                 (w `shiftR` 0x10) .&. 0xff,
                                                                 (w `shiftR` 0x18) .&. 0xff,
                                                                 (w `shiftR` 0x20) .&. 0xff,
                                                                 (w `shiftR` 0x28) .&. 0xff,
                                                                 (w `shiftR` 0x30) .&. 0xff,
                                                                 (w `shiftR` 0x38) .&. 0xff]

instance ToBitVector Int8 where toBitVector v = toBitVector (fromIntegral v :: Word8)
instance ToBitVector Int16 where toBitVector v = toBitVector (fromIntegral v :: Word16)
instance ToBitVector Int32 where toBitVector v = toBitVector (fromIntegral v :: Word32)
instance ToBitVector Int64 where toBitVector v = toBitVector (fromIntegral v :: Word64)

class FromBitVector a where
    fromBitVector :: BitVectorValue -> Maybe a

instance FromBitVector Word8 where
    fromBitVector (BitVectorValue 8 v) = Just $ B.head v
    fromBitVector _ = Nothing

slice :: BitVectorValue -> Size -> Size -> BitVectorValue
slice v start sz =
    unpack v & drop (fromIntegral start) & take (fromIntegral sz) & pack
\ No newline at end of file

A  => src/Common.hs +13 -0
@@ 1,13 @@
module Common where

type Size = Word
data BitVectorSign = Unsigned | Signed deriving (Eq, Ord)
data BitVectorType = BitVectorType BitVectorSign Size deriving (Eq, Ord)

instance Show BitVectorType where
    show (BitVectorType sign sz) = (if sign == Signed then "s" else "u") ++ show sz

fixedPoint :: Eq a => (a -> a) -> a -> a
fixedPoint f v =
    if r == v then v else fixedPoint f r
    where r = f v
\ No newline at end of file

A  => src/Flattening.hs +418 -0
@@ 1,418 @@
module Flattening where

import Text.Printf
import Data.Map (Map)
import qualified Data.Map as Map
import qualified Data.Set as Set
import Control.Monad
import Data.Maybe

import Control.Monad.Except
import Control.Monad.State

import qualified BitVectorValue as BV
import Common
import Formula
import qualified Propositional as P
import Propositional ((<->), (&&&), (|||), (^^^))

newtype FlattenState = FlattenState P.Identifier
data FlattenError =
    TermTypeError Term |
    AtomTypeMismatch Atom |
    AtomPickBoundsError Atom
    deriving (Eq, Show)

type Flattening a = StateT FlattenState (Except FlattenError) a

runFlattening :: Flattening a -> FlattenState -> Either FlattenError a
runFlattening m = runExcept . evalStateT m

type PropVector = Size -> P.Formula
data PropVectorVariable = PropVectorVariable P.Identifier Size

instance Show PropVectorVariable where
    show (PropVectorVariable base sz) = "(" ++ show base ++ ":" ++ show sz ++ ")"

variableVector :: PropVectorVariable -> PropVector
variableVector (PropVectorVariable base sz) i =
    if i < sz then
        P.Var $ base + fromIntegral i
    else
        error "overflow in reserved prop vector"

reserveProps :: Size -> Flattening PropVectorVariable
reserveProps sz = do
    FlattenState nextPropId <- get
    put $ FlattenState (nextPropId + fromIntegral sz)
    return $ PropVectorVariable nextPropId sz

class Reservable a where
    requiredProps :: a -> Flattening Size


reserveVarFor :: (Reservable a) => a -> Flattening PropVectorVariable
reserveVarFor x = requiredProps x >>= reserveProps

reserveVarsForAll :: (Reservable a, Ord a, Foldable t) => t a -> Flattening (Map a PropVectorVariable)
reserveVarsForAll =
    foldM (\map x -> do
            var <- reserveVarFor x
            return $ Map.insert x var map
        ) Map.empty

curPropsCount :: Flattening P.Identifier
curPropsCount = do
    FlattenState nextPropId <- get
    return nextPropId

maybeToFlattening :: FlattenError -> Maybe a -> Flattening a
maybeToFlattening _ (Just v) = return v
maybeToFlattening e Nothing = throwError e

getTermType :: Term -> Flattening BitVectorType
getTermType t = maybeToFlattening (TermTypeError t) $ termType t

skeleton :: (Atom -> PropVectorVariable) -> Formula -> P.Formula
skeleton atomProps (Atom atom) = variableVector (atomProps atom) 0 -- This is simply using the atom's reserved variable
skeleton atomProps (Not f) = P.Not $ skeleton atomProps f
skeleton atomProps (And l r) = skeleton atomProps l &&& skeleton atomProps r

bitwiseConstraintIff :: (Size -> P.Formula) -> (Term -> PropVectorVariable) -> Term -> Flattening P.Formula
bitwiseConstraintIff op termProps t = do
    (BitVectorType _ sz) <- getTermType t
    let tProp = variableVector $ termProps t
    return $ P.conjunction $ map (\i -> P.Iff (tProp i) $ op i) [0..sz - 1]

bitwiseConstraintBinary :: (P.Formula -> P.Formula -> P.Formula) -> (Term -> PropVectorVariable) -> Term -> Term -> Term -> Flattening P.Formula
bitwiseConstraintBinary op termProps l r =
    let lProp = variableVector $ termProps l
        rProp = variableVector $ termProps r in
    bitwiseConstraintIff (\i -> op (lProp i) (rProp i)) termProps

fullAdderSum :: P.Formula -> P.Formula -> P.Formula -> P.Formula
fullAdderSum a b cin = (a ^^^ b) ^^^ cin -- (6.37)

fullAdderCarry :: P.Formula -> P.Formula -> P.Formula -> P.Formula
fullAdderCarry a b cin = (a &&& b) ||| ((a ^^^ b) &&& cin) -- (6.38)

-- (6.39) and (6.42)
adderCarry :: PropVector -> PropVector -> P.Formula -> PropVector
adderCarry _ _ cin 0 = cin
adderCarry l r cin i = fullAdderCarry (l (i-1)) (r (i-1)) cin

adderCarryRec :: PropVector -> PropVector -> Bool -> PropVector
adderCarryRec _ _ cin 0 = P.Const cin
adderCarryRec l r cin i = adderCarry l r (adderCarryRec l r cin (i - 1)) i

adder :: PropVector -> PropVector -> Bool -> Size -> Flattening ([P.Formula], PropVector)
adder l r cin sz = do
    carriesPropVector <- reserveProps (sz-1)
    let carryProp = (\i ->
                if i == 0 then
                    P.Const cin
                else
                    variableVector carriesPropVector (i-1)
            ) :: PropVector
        adderCarryConstraints = map (\i -> carryProp i <-> adderCarry l r (carryProp $ i-1) i) [1..sz-1]
    return (adderCarryConstraints, \i -> fullAdderSum (l i) (r i) (carryProp i))

doubleIf :: P.Formula -> P.Formula -> P.Formula -> P.Formula -> P.Formula -> P.Formula
doubleIf ifa resa ifb resb els =
    (ifa &&& resa) ||| (P.Not ifa &&& ifb &&& resb) ||| (P.Not ifa &&& P.Not ifb &&& els)

singleIf :: P.Formula -> P.Formula -> P.Formula -> P.Formula
singleIf ifa resa els =
    (ifa &&& resa) ||| (P.Not ifa &&& els)

shift :: (Size -> Size -> Size) -> (Int -> Size -> Bool) -> PropVector -> PropVector -> Int -> PropVector
shift _ _ l _ (-1) i = l i -- (6.48)
shift dir cond l r s i | cond s i =
    doubleIf (r $ fromIntegral s)
                (shift dir cond l r (s - 1) (i `dir` (2^s)))
             (P.Not (r $ fromIntegral s))
                (shift dir cond l r (s - 1) i)
             -- else
                (P.Const False)
shift dir cond l r s i = -- (6.49)
    singleIf (P.Not (r $ fromIntegral s))
                (shift dir cond l r (s - 1) i)
             -- else
                (P.Const False)

shiftLStatic :: PropVector -> Size -> PropVector
shiftLStatic x s i = if i < s then P.Const False else x (i - s)

lessThanUnsigned :: PropVector -> PropVector -> Size -> P.Formula
lessThanUnsigned l r sz =
    P.Not $ adderCarryRec l (P.Not . r) True (fromIntegral sz) -- (6.46)

lessThanSigned :: PropVector -> PropVector -> PropVector
lessThanSigned l r sz =
    l (fromIntegral (sz-1)) <-> r (fromIntegral (sz-1))
    ^^^
    adderCarryRec l (P.Not . r) True (fromIntegral sz) -- (6.47) but there is a mistake in the book, see "Errata For 2nd Edition"

mult :: PropVector -> PropVector -> Size -> Int -> Flattening ([P.Formula], PropVector)
mult _ _ _ (-1) = return ([], \_ -> P.Const False) -- (6.50)
mult l r sz s = do
    (prevMultConstraints, prevMultBits) <- mult l r sz (s - 1)
    (adderConstraints, addedBits) <- adder prevMultBits (\i -> r (fromIntegral s) &&& shiftLStatic l (fromIntegral s) i) False sz
    return (adderConstraints ++ prevMultConstraints, addedBits) -- (6.51)

multiplication :: PropVector -> PropVector -> Size -> Flattening ([P.Formula], PropVector)
multiplication l r sz = mult l r sz (fromIntegral sz - 1)

extendUnsigned :: PropVector -> Size -> PropVector
extendUnsigned bv oldsz i
    | i < oldsz = bv i
    | otherwise = P.Const False

extendSigned :: PropVector -> Size -> PropVector
extendSigned bv oldsz i
    | i < oldsz - 1 = bv i
    | otherwise     = bv (oldsz - 1)

extend :: BitVectorSign -> PropVector -> Size -> PropVector
extend Signed = extendSigned
extend Unsigned = extendUnsigned

increment :: PropVector -> Size -> Flattening ([P.Formula], PropVector)
increment v sz = do
    carries <- reserveProps (sz - 1)
    let carryProp = (\i ->
                    if i == 0 then
                        P.Const True
                    else
                        variableVector carries (i-1)
                ) :: PropVector
        carryConstraints = map (\i -> carryProp i <-> if i == 0 then P.Const True else v (i-1) &&& carryProp (i-1)) [1..sz-1]
    return (carryConstraints, \i -> v i ^^^ carryProp i)

absolute :: PropVector -> Size -> Flattening ([P.Formula], PropVector)
absolute v sz = do
    let inverted i = P.Not (v i)
    (tcConstraints, tcVec) <- increment inverted sz
    let signProp = v (sz-1)
    return (tcConstraints, \i -> (signProp &&& tcVec i) ||| (P.Not signProp &&& v i))

lessThanAbsolute :: PropVector -> PropVector -> Size -> Flattening ([P.Formula], P.Formula)
lessThanAbsolute l r sz = do
    (absLConstraints, absLVec) <- absolute l sz
    (absRConstraints, absRVec) <- absolute r sz
    return (absLConstraints ++ absRConstraints, lessThanUnsigned absLVec absRVec sz)

divisionConstraint :: BitVectorSign -> PropVector -> PropVector -> PropVector -> PropVector -> Size -> Flattening P.Formula
divisionConstraint sign res l r rem sz = do
    let extsz = sz + sz
        ext = extend sign
        extl = ext l sz
        extr = ext r sz
        extres = ext res sz
        extrem = ext rem sz
    (multConstraints, multBit) <- multiplication extres extr extsz -- term * r
    (addConstraints, addedBit) <- adder multBit extrem False extsz -- (term * r) + rem
    let multAddConstraints = map (\i -> extl i <-> addedBit i) [0..extsz - 1] -- (6.52)
    remainderConstraints <-
        if sign == Signed then do -- extr
            (extraConstraints, constraint) <- lessThanAbsolute extrem extr extsz
            let signConstraint = (l (sz - 1) <-> rem (sz - 1)) ||| P.conjunction (map (P.Not . rem) [0..sz-1]) -- (sign l == sign rem) || (rem == 0)
            return $ signConstraint : constraint : extraConstraints
        else
            return [lessThanUnsigned extrem extr extsz] -- (6.53)
    return $ P.conjunction $ remainderConstraints ++ multAddConstraints ++ addConstraints ++ multConstraints

termPropVector :: (Term -> PropVectorVariable) -> Term -> PropVector
termPropVector termProps t = variableVector $ termProps t

notTermPropVector :: (Term -> PropVectorVariable) -> Term -> PropVector
notTermPropVector termProps t i = P.Not $ variableVector (termProps t) i

termConstraint :: (Atom -> PropVectorVariable) -> (Term -> PropVectorVariable) -> Term -> Flattening P.Formula
termConstraint atomProps termProps term =
    let termBit = termPropVector termProps
        notTermBit = notTermPropVector termProps in
    case term of
    (Var _ _) -> return $ P.Const True
    (Const _ bv) -> return $ P.conjunction $ map (\i ->
            if BV.index bv i then
                termBit term i
            else
                notTermBit term i
        ) [0..BV.length bv - 1] -- (6.35)
    (BinAnd l r) -> bitwiseConstraintBinary (&&&) termProps l r term
    (BinOr l r) -> bitwiseConstraintBinary (|||) termProps l r term
    --(BinXor l r) -> bitwiseConstraintBinary P.Xor termProps l r term
    (BinXor l r) -> do
        (BitVectorType _ sz) <- getTermType term
        return $ P.And $ map (\i ->
                -- Constraint for the i-th bit, bringing the output in relation to the inputs:
                termBit term i <-> (termBit l i ^^^ termBit r i)
            ) [0..sz - 1]
    (Complement t) -> bitwiseConstraintIff (notTermBit t) termProps term
    (Inc t) -> do
        (BitVectorType _ sz) <- getTermType term
        (incConstraints, incVec) <- increment (termBit t) sz
        return $ P.conjunction $ map (\i -> termBit term i <-> incVec i) [0..sz-1] ++ incConstraints
    (Abs t) -> do
        (BitVectorType sign sz) <- getTermType t
        if sign == Signed then do
            (absConstraints, absVec) <- absolute (termBit t) sz
            return $ P.conjunction $ map (\i -> termBit term i <-> absVec i) [0..sz-1] ++ absConstraints
        else
            return $ P.conjunction $ map (\i -> termBit term i <-> termBit t i) [0..sz-1]
    (Plus l r) -> do
        let (BitVectorType _ sz) = fromJust $ termType term
        (adderConstraints, addedBit) <- adder (termBit l) (termBit r) False sz
        return $ P.conjunction $ adderConstraints ++ map (\i ->
                termBit term i <-> addedBit i  -- (6.41), (6.43)
            ) [0..sz - 1]
    (Minus l r) -> do
        (BitVectorType _ sz) <- getTermType term
        (adderConstraints, addedBit) <- adder (termBit l) (notTermBit r) True sz
        return $ P.conjunction $ adderConstraints ++ map (\i ->
                termBit term i <-> addedBit i -- (6.44)
            ) [0..sz - 1] -- (6.41)
    (ShL l r) -> do
        (BitVectorType _ sz) <- getTermType l -- Term type checking ensures sz == 2^ssz
        (BitVectorType _ ssz) <- getTermType r
        return $ P.conjunction $ map (\i ->
                termBit term i <-> shift (-) (\s i -> i >= 2^s) (termBit l) (termBit r) (fromIntegral ssz - 1) i
            ) [0..fromIntegral sz - 1]
    (ShR l r) -> do
        (BitVectorType _ sz) <- getTermType l -- Term type checking ensures sz == 2^ssz
        (BitVectorType _ ssz) <- getTermType r
        return $ P.conjunction $ map (\i ->
                termBit term i <-> shift (+) (\s i -> i + (2^s) < sz) (termBit l) (termBit r) (fromIntegral ssz - 1) i
            ) [0..fromIntegral sz - 1]
    (Mult l r) -> do
        let (BitVectorType _ sz) = fromJust $ termType term
        (multConstraints, multBit) <- multiplication (termBit l) (termBit r) sz
        return $ P.conjunction $ multConstraints ++ map (\i ->
                termBit term i <-> multBit i
            ) [0..fromIntegral sz - 1]
    (Div l r) -> do
        BitVectorType sign sz <- getTermType l
        remPV <- reserveProps sz
        divisionConstraint sign (termBit term) (termBit l) (termBit r) (variableVector remPV) sz
    (Remainder l r) -> do
        BitVectorType sign sz <- getTermType l
        resPV <- reserveProps sz
        divisionConstraint sign (variableVector resPV) (termBit l) (termBit r) (termBit term) sz
    (Concat _ l r) -> do
        (BitVectorType _ lsz) <- getTermType l
        bitwiseConstraintIff (\i -> if i < lsz then termBit l i else termBit r (i-lsz)) termProps term
    (Ext _ t) -> do
        (BitVectorType sign sz) <- getTermType t
        bitwiseConstraintIff (extend sign (termBit t) sz) termProps term
    (Slice _ off _ t) ->
        bitwiseConstraintIff (\i -> termBit t (off + i)) termProps term
    (Ternary c a b) ->
        let atomProp = variableVector (atomProps c) 0 in
        bitwiseConstraintIff (\i -> (atomProp &&& termBit a i) ||| (P.Not atomProp &&& termBit b i)) termProps term

atomConstraint :: (Atom -> PropVectorVariable) -> (Term -> PropVectorVariable) -> Atom -> Flattening P.Formula
atomConstraint atomProps termProps atom =
    let atomProp = variableVector (atomProps atom) 0
        termBit = termPropVector termProps in
    case atom of
        (BConst True) -> return $ variableVector (atomProps atom) 0
        (BConst False) -> return $ P.Not $ variableVector (atomProps atom) 0
        (Equals l r) -> do
            lt <- getTermType l
            rt <- getTermType r
            when (lt /= rt) $ throwError $ AtomTypeMismatch atom
            (atomProp <->) <$> bitwiseConstraintIff (variableVector (termProps r)) termProps l
        (Pick i t) -> do
            (BitVectorType _ sz) <- getTermType t
            when (i >= sz) $ throwError $ AtomPickBoundsError atom
            return $ atomProp <-> termBit t i
        (LessThan l r) -> do
             lt <- getTermType l
             rt <- getTermType r
             when (lt /= rt) $ throwError $ AtomTypeMismatch atom
             let (BitVectorType sign sz) = lt
             return $ atomProp <->
                if sign == Signed then
                    lessThanSigned (termBit l) (termBit r) sz
                else
                    lessThanUnsigned (termBit l) (termBit r) sz


-- |reserves one propositional variable for each bit in each term
termVars :: Foldable a => a Term -> Flattening (Map Term PropVectorVariable)
termVars =
    foldM (\map term -> do
            (BitVectorType _ sz) <- getTermType term
            baseProp <- reserveProps sz
            return $ Map.insert term baseProp map
        ) Map.empty

instance Reservable Term where
    requiredProps term = (\(BitVectorType _ sz) -> sz) <$> getTermType term

instance Reservable Atom where
    requiredProps _ = return 1

data FlattenedFormula = FlattenedFormula {
    atomProps :: Map Atom PropVectorVariable,
    termProps :: Map Term PropVectorVariable,
    skeletonFormula :: P.Formula,
    termConstraints :: Map Term P.Formula,
    atomConstraints :: Map Atom P.Formula,
    propsCount :: Int
}

-- |Helper function that applies a function in m to each set member and constructs a
-- Map containing the results.
mapFromSetM :: (Ord k, Monad m) => (k -> m a) -> Set.Set k -> m (Map k a)
mapFromSetM f ks = Map.fromList <$> mapM (\a -> f a >>= \c -> return (a, c)) (Set.toList ks)

formulaFlattening :: Formula -> Flattening FlattenedFormula
formulaFlattening f = do
    let allTerms = Set.fromList $ terms f
        allAtoms = Set.fromList $ atoms f
    atomProps <- reserveVarsForAll allAtoms
    termProps <- reserveVarsForAll allTerms
    let skel = skeleton (atomProps Map.!) f
    termConstraints <- mapFromSetM (termConstraint (atomProps Map.!) (termProps Map.!)) allTerms
    atomConstraints <- mapFromSetM (atomConstraint (atomProps Map.!) (termProps Map.!)) allAtoms
    propsCount <- curPropsCount
    return $ FlattenedFormula {
        atomProps = atomProps,
        termProps = termProps,
        skeletonFormula = skel,
        termConstraints = termConstraints,
        atomConstraints = atomConstraints,
        propsCount = propsCount
    }

-- |Convenience function that calls formulaFlattening and evaluates the returned monadic value
flatten :: Formula -> Either FlattenError FlattenedFormula
flatten f = runFlattening (formulaFlattening f) (FlattenState 0)

instance Show FlattenedFormula where
    show (FlattenedFormula atomProps termProps skeletonFormula termConstraints atomConstraints _) =
        printf "skeleton: %s\nterms:\n%satoms:\n%s" (show skeletonFormula) (
                concat $
                    Map.mapWithKey (\term (prop, constraint) -> "  " ++ show term ++ " = " ++ show prop ++ " => " ++ show constraint ++ "\n") $
                    Map.intersectionWith (,) termProps termConstraints
            ) (
                concat $
                    Map.mapWithKey (\atom (prop, constraint) -> "  " ++ show atom ++ " = " ++ show prop ++ " => " ++ show constraint ++ "\n") $
                    Map.intersectionWith (,) atomProps atomConstraints
            )

propositional :: FlattenedFormula -> P.Formula
propositional (FlattenedFormula _ _ skeletonFormula termConstraints atomConstraints _) =
    P.conjunction $ skeletonFormula : Map.elems termConstraints ++ Map.elems atomConstraints

-- |Maps the result from the SAT-solver back to the original bit vector variables
reconstructResult :: Formula -> FlattenedFormula -> Map P.Identifier Bool -> Map Identifier BV.BitVectorValue
reconstructResult f flat propResults =
    let allVars = Set.fromList $ vars f in
    Map.fromList $ map (\(BitVectorType sign sz, name) ->
            let (PropVectorVariable baseProp _) = termProps flat Map.! Var (BitVectorType sign sz) name
                bits = map (\i -> Map.findWithDefault False (baseProp + i) propResults) [0..fromIntegral sz - 1] in
            (name, BV.pack bits)
        ) $ Set.toList allVars

A  => src/Formula.hs +262 -0
@@ 1,262 @@
{-# LANGUAGE PatternSynonyms #-}
module Formula where

import Text.Printf

import Common
import qualified BitVectorValue as BV

type Identifier = String

data Formula =
    And Formula Formula |
    Not Formula |
    Atom Atom
    deriving (Eq, Ord)

data Atom =
    BConst Bool |
    LessThan Term Term |
    Equals Term Term |
    Pick Size Term
    deriving (Eq, Ord)

data Term =
    Plus Term Term |
    Minus Term Term |
    Mult Term Term |
    Div Term Term |
    Remainder Term Term |
    ShL Term Term |
    ShR Term Term |
    BinAnd Term Term |
    BinOr Term Term |
    BinXor Term Term |
    Var BitVectorType Identifier |
    Complement Term |
    Inc Term |
    Abs Term |
    Const BitVectorSign BV.BitVectorValue |
    Ternary Atom Term Term |
    Concat BitVectorSign Term Term |
    Ext Size Term |
    Slice BitVectorSign Size Size Term -- new sign -> start offset -> new size -> term
    deriving (Eq, Ord)

pattern (:&&:) a b = And a b
pattern (:!!:) a = Not a

pattern (:==:) a b = Equals a b
pattern (:<:) a b = LessThan a b

pattern (:+:) a b = Plus a b
pattern (:-:) a b = Minus a b
pattern (:*:) a b = Mult a b
pattern (:/:) a b = Div a b
pattern (:%:) a b = Remainder a b
pattern (:<<:) a b = ShL a b
pattern (:>>:) a b = ShR a b
pattern (:&:) a b = BinAnd a b
pattern (:|:) a b = BinOr a b
pattern (:^:) a b = BinXor a b

uVar :: BV.Size -> Identifier -> Term
uVar sz = Var (BitVectorType Unsigned sz)

sVar :: BV.Size -> Identifier -> Term
sVar sz = Var (BitVectorType Signed sz)

uConst :: BV.ToBitVector a => a -> Term
uConst v = Const Unsigned $ BV.toBitVector v

sConst :: BV.ToBitVector a => a -> Term
sConst v = Const Signed $ BV.toBitVector v

instance Show Formula where
    show (And l r)          = printf "(%s ∧ %s)" (show l) (show r)
    show (Not f)            = printf "¬%s" (show f)
    show (Atom a)           = show a

instance Show Atom where
    show (BConst True)      = printf "True"
    show (BConst False)     = printf "False"
    show (LessThan l r)     = printf "(%s < %s)" (show l) (show r)
    show (Equals l r)       = printf "(%s = %s)" (show l) (show r)
    show (Pick i t)         = printf "%s[%s]" (show t) (show i)

instance Show Term where
    show (Plus l r)         = printf "(%s + %s)" (show l) (show r)
    show (Minus l r)        = printf "(%s - %s)" (show l) (show r)
    show (Mult l r)         = printf "(%s * %s)" (show l) (show r)
    show (Div l r)          = printf "(%s / %s)" (show l) (show r)
    show (Remainder l r)    = printf "(%s %% %s)" (show l) (show r)
    show (ShL l r)          = printf "(%s << %s)" (show l) (show r)
    show (ShR l r)          = printf "(%s >> %s)" (show l) (show r)
    show (BinAnd l r)       = printf "(%s & %s)" (show l) (show r)
    show (BinOr l r)        = printf "(%s | %s)" (show l) (show r)
    show (BinXor l r)       = printf "(%s ^ %s)" (show l) (show r)
    show (Concat _ l r)     = printf "(%s ⚬ %s)" (show l) (show r)
    show (Var _ name)       = name
    show (Complement term)  = printf "~%s" (show term)
    show (Inc term)         = printf "%s+1" (show term)
    show (Abs term)         = printf "|%s|" (show term)
    show (Const _ bv)       = show bv
    show (Ternary c a b)    = printf "(%s ? %s : %s)" (show c) (show a) (show b)
    show (Ext sz term)      = printf "ext_%s %s" (show sz) (show term)
    show (Slice _ off sz t) = printf "%s[%s:%s]" (show t) (show off) (show sz)

combinedTermTypes :: Term -> Term -> Maybe BitVectorType
combinedTermTypes l r =
    case (termType l, termType r) of
        (Just tl, Just tr) | tl == tr -> Just tl
        _ -> Nothing

shiftTermTypes :: Term -> Term -> Maybe BitVectorType
shiftTermTypes l r =
    case (termType l, termType r) of
        (Just (BitVectorType sign sz), Just (BitVectorType Unsigned ssz)) | sz == 2 ^ ssz -> Just $ BitVectorType sign sz
        _ -> Nothing

-- |returns the term's type or Nothing if it is invalid wrt. typing
termType :: Term -> Maybe BitVectorType
termType (Plus l r) = combinedTermTypes l r
termType (Minus l r) = combinedTermTypes l r
termType (Mult l r) = combinedTermTypes l r
termType (Div l r) = combinedTermTypes l r
termType (Remainder l r) = combinedTermTypes l r
termType (ShL l r) = shiftTermTypes l r
termType (ShR l r) = shiftTermTypes l r
termType (BinAnd l r) = combinedTermTypes l r
termType (BinOr l r) = combinedTermTypes l r
termType (BinXor l r) = combinedTermTypes l r
termType (Concat sign l r) = do
    (BitVectorType _ lsz) <- termType l
    (BitVectorType _ rsz) <- termType r
    return $ BitVectorType sign (lsz + rsz)
termType (Var tp _) = Just tp
termType (Complement term) = termType term
termType (Inc term) = termType term
termType (Abs term) = (\(BitVectorType _ sz) -> BitVectorType Unsigned sz) <$> termType term
termType (Const sign bv) = Just $ BitVectorType sign (BV.length bv)
termType (Ternary _ a b) = combinedTermTypes a b
termType (Ext sz term) =
    case termType term of
        Just (BitVectorType sign tsz) | tsz <= sz -> Just $ BitVectorType sign sz
        _ -> Nothing
termType (Slice sign off sz term) =
    case termType term of
        Just (BitVectorType _ tsz) | off + sz <= tsz -> Just $ BitVectorType sign sz
        _ -> Nothing

subTerms :: Term -> [Term]
subTerms (Plus l r) = [l, r]
subTerms (Minus l r) = [l, r]
subTerms (Mult l r) = [l, r]
subTerms (Div l r) = [l, r]
subTerms (Remainder l r) = [l, r]
subTerms (ShL l r) = [l, r]
subTerms (ShR l r) = [l, r]
subTerms (BinAnd l r) = [l, r]
subTerms (BinOr l r) = [l, r]
subTerms (BinXor l r) = [l, r]
subTerms (Concat _ l r) = [l, r]
subTerms (Var _ _) = []
subTerms (Complement term) = [term]
subTerms (Inc term) = [term]
subTerms (Abs term) = [term]
subTerms (Const _ _) = []
subTerms (Ternary _ a b) = [a, b]
subTerms (Ext _ term) = [term]
subTerms (Slice _ _ _ t) = [t]

class Terms a where
    terms :: a -> [Term]

instance Terms Term where
    terms term =
        term : concatMap terms at ++ concatMap terms st
        where st = subTerms term
              at = case term of
                (Ternary c _ _) -> terms c
                _ -> []

instance Terms Formula where
    terms (And l r) = terms l ++ terms r
    terms (Not f) = terms f
    terms (Atom a) = terms a

instance Terms Atom where
    terms (BConst _) = []
    terms (LessThan l r) = terms l ++ terms r
    terms (Equals l r) = terms l ++ terms r
    terms (Pick _ t) = terms t

class Atoms a where
    atoms :: a -> [Atom]

instance Atoms Formula where
    atoms (And l r) = atoms l ++ atoms r
    atoms (Not f) = atoms f
    atoms (Atom a) = atoms a

instance Atoms Atom where
    atoms (BConst b) = [BConst b]
    atoms (LessThan l r) = LessThan l r : atoms l ++ atoms r
    atoms (Equals l r) = Equals l r : atoms l ++ atoms r
    atoms (Pick i t) = Pick i t : atoms t

instance Atoms Term where
    atoms (Plus l r) = atoms l ++ atoms r
    atoms (Minus l r) = atoms l ++ atoms r
    atoms (Mult l r) = atoms l ++ atoms r
    atoms (Div l r) = atoms l ++ atoms r
    atoms (Remainder l r) = atoms l ++ atoms r
    atoms (ShL l r) = atoms l ++ atoms r
    atoms (ShR l r) = atoms l ++ atoms r
    atoms (BinAnd l r) = atoms l ++ atoms r
    atoms (BinOr l r) = atoms l ++ atoms r
    atoms (BinXor l r) = atoms l ++ atoms r
    atoms (Concat _ l r) = atoms l ++ atoms r
    atoms (Var _ _) = []
    atoms (Complement t) = atoms t
    atoms (Inc t) = atoms t
    atoms (Abs t) = atoms t
    atoms (Const _ _) = []
    atoms (Ternary c a b) = atoms c ++ atoms a ++ atoms b
    atoms (Ext _ t) = atoms t
    atoms (Slice _ _ _ t) = atoms t

class Vars a where
    vars :: a -> [(BitVectorType, Identifier)]

instance Vars Formula where
    vars (And l r) = vars l ++ vars r
    vars (Not f) = vars f
    vars (Atom a) = vars a

instance Vars Atom where
    vars (BConst _) = []
    vars (LessThan l r) = vars l ++ vars r
    vars (Equals l r) = vars l ++ vars r
    vars (Pick _ t) = vars t

instance Vars Term where
    vars (Plus l r) = vars l ++ vars r
    vars (Minus l r) = vars l ++ vars r
    vars (Mult l r) = vars l ++ vars r
    vars (Div l r) = vars l ++ vars r
    vars (Remainder l r) = vars l ++ vars r
    vars (ShL l r) = vars l ++ vars r
    vars (ShR l r) = vars l ++ vars r
    vars (BinAnd l r) = vars l ++ vars r
    vars (BinOr l r) = vars l ++ vars r
    vars (BinXor l r) = vars l ++ vars r
    vars (Concat _ l r) = vars l ++ vars r
    vars (Var tp name) = [(tp, name)]
    vars (Complement t) = vars t
    vars (Inc t) = vars t
    vars (Abs t) = vars t
    vars (Const _ _) = []
    vars (Ternary c a b) = vars c ++ vars a ++ vars b
    vars (Ext _ t) = vars t
    vars (Slice _ _ _ t) = vars t
\ No newline at end of file

A  => src/MiniSat.hs +18 -0
@@ 1,18 @@
module MiniSat where

import qualified SAT.MiniSat as M

import qualified Propositional as P

-- |Convert our representation of propositional formulas to the one accepted by SAT.MiniSat
miniSat :: P.Formula -> M.Formula P.Identifier
miniSat (P.Iff l r) = miniSat l M.:<->: miniSat r
miniSat (P.Impl l r) = miniSat l M.:->: miniSat r
--miniSat (P.And l r) = miniSat l M.:&&: miniSat r
--miniSat (P.Or l r) = miniSat l M.:||: miniSat r
miniSat (P.And fs) = M.All $ map miniSat fs
miniSat (P.Or fs) = M.Some $ map miniSat fs
miniSat (P.Xor l r) = miniSat l M.:++: miniSat r
miniSat (P.Not f) = M.Not $ miniSat f
miniSat (P.Var id) = M.Var id
miniSat (P.Const c) = if c then M.Yes else M.No
\ No newline at end of file

A  => src/Propositional.hs +98 -0
@@ 1,98 @@
{-# LANGUAGE LambdaCase #-}

module Propositional (
    Identifier,
    Formula (..),
    (<->),
    (-->),
    (&&&),
    (|||),
    (^^^),
    (Propositional.!!),
    conjunction,
    elimAllConsts,
    eval
) where

import Text.Printf
import Data.List

import Common

type Identifier = Int

data Formula =
    Iff Formula Formula |
    Impl Formula Formula |
    And [Formula] |
    Or [Formula] |
    Xor Formula Formula |
    Not Formula |
    Var Identifier |
    Const Bool
    deriving (Eq)

instance Show Formula where
    show (Iff l r) = printf "(%s ↔ %s)" (show l) (show r)
    show (Impl l r) = printf "(%s → %s)" (show l) (show r)
    show (And fs) = "(" ++ intercalate " ∧ " (map show fs) ++ ")"
    show (Or fs) = "(" ++ intercalate " ∨ " (map show fs) ++ ")"
    show (Xor l r) = printf "(%s ⊕ %s)" (show l) (show r)
    show (Not f)   = printf "¬%s" (show f)
    show (Var a)   = show a
    show (Const b) = show b

(<->) = Iff;
(-->) = Impl;
(&&&) l r = And [l, r];
(|||) l r = Or [l, r]
(^^^) = Xor;
(!!) = Not

conjunction :: [Formula] -> Formula
conjunction = And

elimConst :: Formula -> Formula
elimConst (Iff l (Const True)) = elimConst l
elimConst (Iff l (Const False)) = elimConst $ Not l
elimConst (Iff (Const True) r) = elimConst r
elimConst (Iff (Const False) r) = elimConst $ Not r
elimConst (Iff l r) = Iff (elimConst l) (elimConst r)
elimConst (Impl (Const True) r) = elimConst r
elimConst (Impl (Const False) _) = Const True
elimConst (Impl _ (Const True)) = Const True
elimConst (Impl l (Const False)) = Not $ elimConst l
elimConst (Impl l r) = Impl (elimConst l) (elimConst r)
elimConst (And fs) =
    if any (\case Const False -> True; _ -> False) fs then
        Const False
    else
        And $ filter (\case Const True -> False; _ -> True) $ map elimConst fs
elimConst (Or fs) =
    if any (\case Const True -> True; _ -> False) fs then
        Const True
    else
        And $ filter (\case Const False -> False; _ -> True) $ map elimConst fs
elimConst (Xor l (Const True)) = Not $ elimConst l
elimConst (Xor l (Const False)) = elimConst l
elimConst (Xor (Const True) r) = Not $ elimConst r
elimConst (Xor (Const False) r) = elimConst r
elimConst (Xor l r) = Xor (elimConst l) (elimConst r)
elimConst (Not (Const True)) = Const False
elimConst (Not (Const False)) = Const True
elimConst (Not f) = Not $ elimConst f
elimConst (Var id) = Var id
elimConst (Const v) = Const v

elimAllConsts :: Formula -> Formula
elimAllConsts = fixedPoint elimConst

eval :: (Identifier -> Bool) -> Formula -> Bool
eval ass (Iff l r) = eval ass l == eval ass r
eval ass (Impl l r) = eval ass l || (eval ass l && eval ass r)
eval ass (And fs) = foldl (\acc f -> acc && eval ass f) True fs
eval ass (Or fs) = foldl (\acc f -> acc || eval ass f) False fs
eval ass (Xor l r) = eval ass l /= eval ass r
eval ass (Not f) = not $ eval ass f
eval ass (Var id) = ass id
eval _   (Const c) = c
\ No newline at end of file

A  => src/Solve.hs +96 -0
@@ 1,96 @@
module Solve (
    SolveResult (..),
    Solution,
    solve,
    solveAll,
    solveIncremental,
    costEstimate
) where

import Data.Map (Map)
import qualified Data.Map as Map
import Data.List
-- import Debug.Trace

import qualified SAT.MiniSat as M

import qualified BitVectorValue as BV
import qualified Propositional as P
import Formula
import Flattening
import MiniSat

data SolveResult a =
    Solution a |
    Unsatisfiable |
    FlattenError FlattenError
    deriving (Eq, Show)

type Solution = Map Identifier BV.BitVectorValue

-- |Solve to a single solution
solve :: Formula -> SolveResult Solution
solve f =
    case flatten f of
        Left e -> FlattenError e
        Right flat ->
            case M.solve $ miniSat $ propositional flat of
                Nothing -> Unsatisfiable
                Just r -> Solution $ reconstructResult f flat r

-- |Solve to all solutions as a lazy list
solveAll :: Formula -> SolveResult [Solution]
solveAll f =
    case flatten f of
        Left e -> FlattenError e
        Right flat ->
            case M.solve_all $ miniSat $ propositional flat of
                [] -> Unsatisfiable
                sols -> Solution $ map (reconstructResult f flat) sols

-- |Solve incrementally to a single solution
-- This can be significantly faster or slower than solve depending on the
-- formula, see the paper for more info.
solveIncremental :: Int -> Formula -> SolveResult Solution
solveIncremental steps f =
    case flatten f of
        Left e -> FlattenError e
        Right flat -> solveFlattenedIncremental steps f flat

costEstimate :: P.Formula -> Word
costEstimate (P.Iff l r) = 1 + costEstimate l + costEstimate r
costEstimate (P.Impl l r) = 1 + costEstimate l + costEstimate r
costEstimate (P.And fs) = foldl (\acc f -> acc + costEstimate f) (1 + fromIntegral (length fs)) fs
costEstimate (P.Or fs) = foldl (\acc f -> acc + costEstimate f) (1 + fromIntegral (length fs)) fs
costEstimate (P.Xor l r) = 1 + costEstimate l + costEstimate r
costEstimate (P.Not f) = costEstimate f
costEstimate (P.Var _) = 1
costEstimate (P.Const _) = 0

-- |Solve a formula incrementally, given the number of new constraints to add in each step
solveFlattenedIncremental :: Int -> Formula -> FlattenedFormula -> SolveResult Solution
solveFlattenedIncremental stepSize f flat =
    let (FlattenedFormula _ _ skeletonFormula termConstraints atomConstraints _) = flat
        initialFormulas = [skeletonFormula]
        incrementalFormulas = sortOn costEstimate $ filter (/= P.Const True) $ Map.elems termConstraints ++ Map.elems atomConstraints
        fullFormula = propositional flat
    in case incrementalSAT stepSize fullFormula initialFormulas incrementalFormulas of
        Nothing -> Unsatisfiable
        Just r -> Solution $ reconstructResult f flat r

-- |Solve a SAT problem incrementally by recursion, given the number of new constraints to add in
-- each step, the full formula, constraints to be considered right now and constraints to be
-- considered later.
incrementalSAT :: Int -> P.Formula -> [P.Formula] -> [P.Formula] -> Maybe (Map P.Identifier Bool)
incrementalSAT stepSize full current pending = -- trace ("incrementalSat " ++ show (length current) ++ "/" ++ show (length pending)) $
    case M.solve $ miniSat $ P.conjunction current of
        Nothing -> Nothing -- partial formula unsatisfiable => full formula unsatisfiable
        Just r -> -- partial formula satisfiable
            let conflicts = filter (not . P.eval (\id -> Map.findWithDefault False id r)) pending in
            if null conflicts then
                Just r -- no conflicts, full formula satisfied!
            else
                -- got conflicts, move the easiest ones into the current list
                let new = take stepSize conflicts -- pick the easiest conflicts
                    nextPending = filter (not . (`elem` new)) pending in -- remove them from pending
                incrementalSAT stepSize full (new ++ current) nextPending

A  => stack.yaml +66 -0
@@ 1,66 @@
# This file was automatically generated by 'stack init'
#
# Some commonly used options have been documented as comments in this file.
# For advanced use and comprehensive documentation of the format, please see:
# https://docs.haskellstack.org/en/stable/yaml_configuration/

# Resolver to choose a 'specific' stackage snapshot or a compiler version.
# A snapshot resolver dictates the compiler version and the set of packages
# to be used for project dependencies. For example:
#
# resolver: lts-3.5
# resolver: nightly-2015-09-21
# resolver: ghc-7.10.2
#
# The location of a snapshot can be provided as a file or url. Stack assumes
# a snapshot provided as a file might change, whereas a url resource does not.
#
# resolver: ./custom-snapshot.yaml
# resolver: https://example.com/snapshots/2018-01-01.yaml
resolver: lts-12.26

# User packages to be built.
# Various formats can be used as shown in the example below.
#
# packages:
# - some-directory
# - https://example.com/foo/bar/baz-0.0.2.tar.gz
#   subdirs:
#   - auto-update
#   - wai
packages:
- .
# Dependency packages to be pulled from upstream that are not in the resolver.
# These entries can reference officially published versions as well as
# forks / in-progress versions pinned to a git hash. For example:
#
# extra-deps:
# - acme-missiles-0.3
# - git: https://github.com/commercialhaskell/stack.git
#   commit: e7b331f14bcffb8367cd58fbfc8b40ec7642100a
#
# extra-deps: []

# Override default flag values for local packages and extra-deps
# flags: {}

# Extra package databases containing global packages
# extra-package-dbs: []

# Control whether we use the GHC we find on the path
# system-ghc: true
#
# Require a specific version of stack, using version ranges
# require-stack-version: -any # Default
# require-stack-version: ">=2.3"
#
# Override the architecture used by stack, especially useful on Windows
# arch: i386
# arch: x86_64
#
# Extra directories used by stack for building
# extra-include-dirs: [/path/to/dir]
# extra-lib-dirs: [/path/to/dir]
#
# Allow a newer minor version of GHC than the snapshot specifies
# compiler-check: newer-minor

A  => test/BitVectorValueTest.hs +50 -0
@@ 1,50 @@
{-# LANGUAGE TemplateHaskell #-}
module BitVectorValueTest (runTests) where

import Test.QuickCheck (choose, Gen, Arbitrary, arbitrary, sized)
import Test.QuickCheck.All

import Text.Printf
import Data.Word
import Data.Bits
import Control.Monad

import BitVectorValue as BV

instance Arbitrary BV.BitVectorValue where
    arbitrary = choose (1, 128) >>= \n -> BV.pack <$> replicateM n arbitrary

prop_replicate :: Bool -> Gen Bool
prop_replicate v = do
    sz <- choose (1, 128) :: Gen Word
    let bv = BV.replicate sz v
    return $ foldl (\acc i -> acc && (BV.index bv i == v)) True [0..sz-1]

checkBase :: (ToBitVector a, Bits a, Num a) => BV.Size -> a -> Bool
checkBase sz v =
    let bv = BV.toBitVector v in
    BV.length bv == sz && foldl (\acc i -> acc && (BV.index bv i == (v .&. (1 `shiftL` fromIntegral i) /= 0))) True [0..sz-1]

prop_base8 = checkBase 8 :: Word8 -> Bool
prop_base16 = checkBase 16 :: Word16 -> Bool
prop_base32 = checkBase 32 :: Word32 -> Bool
prop_base64 = checkBase 64 :: Word64 -> Bool

prop_eq :: BV.BitVectorValue -> Bool
prop_eq bv = bv == bv

prop_neq :: Gen Bool
prop_neq = do
    bitsa <- choose (1, 128) >>= \n -> replicateM n (arbitrary::Gen Bool)
    bitsb <- choose (1, 128) >>= \n -> replicateM n (arbitrary::Gen Bool)
    return $ (bitsa == bitsb) == (BV.pack bitsa == BV.pack bitsb)

prop_compare_eq :: BV.BitVectorValue -> Bool
prop_compare_eq bv = compare bv bv == EQ

prop_compare :: Word64 -> Word64 -> Bool
prop_compare a b = compare a b == compare (BV.toBitVector a) (BV.toBitVector b)

return []
runTests :: IO Bool
runTests = $quickCheckAll
\ No newline at end of file

A  => test/SolveTest.hs +170 -0
@@ 1,170 @@
{-# LANGUAGE TemplateHaskell #-}
module SolveTest (runTests) where

import Test.QuickCheck (choose, Gen, Arbitrary, arbitrary, sized, (===), Property, property)
import Test.QuickCheck.All

import Data.Word
import Data.Int
import Data.Bits
import Data.Maybe
import Data.Map (Map)
import qualified Data.Map as Map

import Common
import Formula
import Solve
import qualified BitVectorValue as BV

example0 x y = (Atom $ uConst x :==: uVar 8 "a")
               :&&:
               (Atom $ uVar 8 "b" :==: (uVar 8 "a" :^: uConst y))

prop_example0 x y =
    let f = example0 (x::Word8) (y::Word8) in
    solve f == Solution (Map.fromList [("a", BV.toBitVector x), ("b", BV.toBitVector (x `xor` y))])

prop_example0Incremental x y =
    let f = example0 (x::Word8) (y::Word8) in
    solveIncremental 3 f === Solution (Map.fromList [("a", BV.toBitVector x), ("b", BV.toBitVector (x `xor` y))])

prop_inc x =
    let f = Atom $ uVar 8 "a" :==: Inc (uConst (x::Word8)) in
    solve f == Solution (Map.fromList [("a", BV.toBitVector (x+1))])

prop_abs x =
    let f = Atom $ uVar 8 "a" :==: Abs (sConst (x :: Int8))
    in solve f == Solution (Map.fromList [("a", BV.toBitVector (fromIntegral (abs x) :: Word8))])

checkOperator :: BV.ToBitVector a => (Term -> Term -> Term) -> (a -> a -> a) -> BitVectorSign -> a -> a -> Bool
checkOperator top op sign x y =
    let (mVar, mConst) = if sign == Signed then (sVar, sConst) else (uVar, uConst)
        f = Atom $ mVar 8 "a" :==: (mConst x `top` mConst y) in
    solve f == Solution (Map.fromList [("a", BV.toBitVector (x `op` y))])

prop_plus x y = checkOperator (:+:) (+) Unsigned (x::Word8) (y::Word8)
prop_plusS x y = checkOperator (:+:) (+) Signed (x::Int8) (y::Int8)
prop_minus x y = checkOperator (:-:) (-) Unsigned (x::Word8) (y::Word8)
prop_minusS x y = checkOperator (:-:) (-) Signed (x::Int8) (y::Int8)

checkDiv :: (BV.ToBitVector a, Integral a) => BitVectorSign -> a -> a -> Bool
checkDiv sign x y =
    let (mVar, mConst) = if sign == Signed then (sVar, sConst) else (uVar, uConst)
        f = Atom $ mVar 8 "a" :==: (mConst x :/: mConst y) in
    solveAll f == if y == 0 then Unsatisfiable else Solution [Map.fromList [("a", BV.toBitVector (x `quot` y))]]

prop_concat :: Word8 -> Word8 -> Bool
prop_concat x y =
    let f = Atom $ sVar 16 "a" :==: Concat Signed (uConst x) (uConst y)
        v = fromIntegral ((fromIntegral x::Word16) .|. ((fromIntegral y::Word16) `shiftL` 8))::Word16 in
    solve f == Solution (Map.fromList [("a", BV.toBitVector v)])

prop_extz :: Word8 -> Property
prop_extz x =
    let f = Atom $ uVar 16 "a" :==: Ext 16 (uConst x) in
    solve f === Solution (Map.fromList [("a", BV.toBitVector (fromIntegral x :: Word16))])

prop_exts :: Int8 -> Property
prop_exts x =
    let f = Atom $ sVar 16 "a" :==: Ext 16 (sConst x) in
    solve f === Solution (Map.fromList [("a", BV.toBitVector (fromIntegral x :: Int16))])

prop_slice :: Word64 -> Gen Property
prop_slice x = do
    let bv = BV.toBitVector x
    off <- choose (0, 62)
    sz <- choose (1, 64 - off)
    let f = Atom $ uVar sz "a" :==: Slice Unsigned off sz (Const Signed bv)
    return $ solve f === Solution (Map.fromList [("a", BV.slice bv off sz)])

prop_complement :: Word8 -> Bool
prop_complement x =
    let f = Atom $ uVar 8 "a" :==: Complement (uConst x) in
    solve f == Solution (Map.fromList [("a", BV.toBitVector (x `xor` 0xff))])

prop_ternary :: Bool -> Word8 -> Word8 -> Property
prop_ternary c a b =
    let f = Atom $ uVar 8 "a" :==: Ternary (BConst c) (uConst a) (uConst b) in
    solve f === Solution (Map.fromList [("a", BV.toBitVector $ if c then a else b)])

prop_ternary1 :: Word8 -> Word8 -> Word8 -> Word8 -> Property
prop_ternary1 ca cb a b =
    let f = Atom $ uVar 8 "a" :==: Ternary (uConst ca :==: uConst cb) (uConst a) (uConst b) in
    solve f === Solution (Map.fromList [("a", BV.toBitVector $ if ca == cb then a else b)])

prop_atomEquals x =
    let f = Atom $ uVar 8 "a" :==: uConst (x::Word8) in
    solve f == Solution (Map.fromList [("a", BV.toBitVector x)])

bconjunction :: [Formula] -> Formula
bconjunction [x] = x
bconjunction [x, y] = And x y
bconjunction (x : xs) = And x $ bconjunction xs
bconjunction [] = undefined

prop_atomPick :: Word8 -> Bool
prop_atomPick x =
    let f = bconjunction $ map (\i ->
                if ((x `shiftR` i) .&. 1) /= 0 then
                    Atom $ Pick (fromIntegral i) (uVar 8 "a")
                else
                    Not $ Atom $ Pick (fromIntegral i) (uVar 8 "a")
            ) [0..7] in
    solve f == Solution (Map.fromList [("a", BV.toBitVector x)])

prop_atomLessThanUnsigned :: Word8 -> Bool
prop_atomLessThanUnsigned x =
    let f = bconjunction $
            (if x == 0 then [] else [
                Atom $ uConst (x-1) :<: uVar 8 "a"
            ]) ++ (if x == 255 then [] else [
                Atom $ uVar 8 "a" :<: uConst (x+1)
            ]) in
    solve f == Solution (Map.fromList [("a", BV.toBitVector x)])

prop_atomLessThanSigned :: Int8 -> Bool
prop_atomLessThanSigned x =
    let f = bconjunction $
            (if x == -128 then [] else [
                Atom $ sConst (x-1) :<: sVar 8 "a"
            ]) ++ (if x == 127 then [] else [
                Atom $ sVar 8 "a" :<: sConst (x+1)
            ]) in
    solve f == Solution (Map.fromList [("a", BV.toBitVector x)])

prop_shiftL :: Word8 -> Word8 -> Bool
prop_shiftL x s =
    let f = Atom $ uVar 8 "a" :==: (uConst x :<<: Const Unsigned (BV.slice (BV.toBitVector s) 0 3)) in
    solve f == Solution (Map.fromList [("a", BV.toBitVector (x `shiftL` fromIntegral (s .&. 0x7)))])

prop_shiftR :: Word8 -> Word8 -> Bool
prop_shiftR x s =
    let f = Atom $ uVar 8 "a" :==: (uConst x :>>: Const Unsigned (BV.slice (BV.toBitVector s) 0 3)) in
    solve f == Solution (Map.fromList [("a", BV.toBitVector (x `shiftR` fromIntegral (s .&. 0x7)))])

prop_incrementalUnsatisfiable :: Property
prop_incrementalUnsatisfiable =
    let f = Atom ((uVar 64 "a" :*: uVar 64 "b") :==: uVar 64 "c")
            :&&: Not (Atom ((uVar 64 "b" :*: uVar 64 "a") :==: uVar 64 "c"))
            :&&: Atom (uVar 64 "x" :<: uVar 64 "y")
            :&&: Atom (uVar 64 "y" :<: uVar 64 "x") in
    solveIncremental 1 f === Unsatisfiable

--prop_incrementalSatisfiable :: Word64 -> Property
--prop_incrementalSatisfiable x =
--    let f = Atom (uVar 64 "a" :==: uConst x)
--            :&&: Not (     Not (Atom $ (uVar 64 "b" :*: uVar 64 "c") :<: uVar 64 "d")
--                      :&&: Not (Atom $ uVar 64 "d" :<: (uVar 64 "b" :*: uVar 64 "c")))
--        sol = solveIncremental 1 f in
--    case sol of
--        Solution m -> m Map.! "a" === BV.toBitVector x
--        _ -> property False

prop_mult x y = checkOperator (:*:) (*) Unsigned (x::Word8) (y::Word8)
prop_multS x y = checkOperator (:*:) (*) Signed (x::Int8) (y::Int8)
prop_div x y = checkDiv Unsigned (x::Word8) (y::Word8)
prop_divS x y = checkDiv Signed (x::Int8) (y::Int8)

return []
runTests :: IO Bool
runTests = $quickCheckAll
\ No newline at end of file

A  => test/Spec.hs +11 -0
@@ 1,11 @@
import System.Exit

import qualified BitVectorValueTest
import qualified SolveTest

main :: IO ()
main = do
    good <- and <$> sequence [BitVectorValueTest.runTests, SolveTest.runTests]
    if good
        then exitSuccess
        else exitFailure