Copyright | (c) Levent Erkok |
---|---|
License | BSD3 |
Maintainer | erkokl@gmail.com |
Stability | experimental |
Safe Haskell | None |
Language | Haskell2010 |
- Symbolic types
- Arrays of symbolic values
- Creating symbolic values
- Symbolic Equality and Comparisons
- Conditionals: Mergeable values
- Symbolic integral numbers
- Division and Modulus
- Bit-vector operations
- IEEE-floating point numbers
- Enumerations
- Uninterpreted sorts, axioms, constants, and functions
- Adding SMT functions
- Properties, proofs, and satisfiability
- Constraints
- Checking safety
- Quick-checking
- Optimization
- Model extraction
- SMT Interface
- Abstract SBV type
- Module exports
(The sbv library is hosted at http://github.com/LeventErkok/sbv. Comments, bug reports, and patches are always welcome.)
SBV: SMT Based Verification
Express properties about Haskell programs and automatically prove them using SMT solvers.
>>>
prove $ \x -> x `shiftL` 2 .== 4 * (x :: SWord8)
Q.E.D.
>>>
prove $ \x -> x `shiftL` 2 .== 2 * (x :: SWord8)
Falsifiable. Counter-example: s0 = 64 :: Word8
The function prove
has the following type:
prove
::Provable
a => a ->IO
ThmResult
The class Provable
comes with instances for n-ary predicates, for arbitrary n.
The predicates are just regular Haskell functions over symbolic types listed below.
Functions for checking satisfiability (sat
and allSat
) are also
provided.
The sbv library introduces the following symbolic types:
SBool
: Symbolic Booleans (bits).SWord8
,SWord16
,SWord32
,SWord64
: Symbolic Words (unsigned).SInt8
,SInt16
,SInt32
,SInt64
: Symbolic Ints (signed).SWord
n
: Generalized symbolic words of arbitrary bit-size.SInt
n
: Generalized symbolic ints of arbitrary bit-size.SInteger
: Unbounded signed integers.SReal
: Algebraic-real numbers.SFloat
: IEEE-754 single-precision floating point values.SDouble
: IEEE-754 double-precision floating point values.SRational
: Rationals. (Ratio of two symbolic integers.)SFloatingPoint
: Generalized IEEE-754 floating point values, with user specified exponent and mantissa widths.SChar
,SString
,RegExp
: Characters, strings and regular expressions.SList
: Symbolic lists (which can be nested)STuple
,STuple2
,STuple3
, ..,STuple8
: Symbolic tuples (upto 8-tuples, can be nested)SEither
: Symbolic sumsSMaybe
: Symbolic optional values.SSet
: Symbolic sets.SArray
: Arrays of symbolic values.- Symbolic polynomials over GF(2^n), polynomial arithmetic, and CRCs.
- Uninterpreted constants and functions over symbolic values, with user defined SMT-Lib axioms.
- Uninterpreted sorts, and proofs over such sorts, potentially with axioms.
- Model validation: SBV can validate models returned by solvers, which allows
for protection against bugs in SMT solvers and SBV itself. (See the
validateModel
parameter.)
The user can construct ordinary Haskell programs using these types, which behave
very similar to their concrete counterparts. In particular these types belong to the
standard classes Num
, Bits
, custom versions of Eq
(EqSymbolic
)
and Ord
(OrdSymbolic
), along with several other custom classes for simplifying
programming with symbolic values. The framework takes full advantage of Haskell's type
inference to avoid many common mistakes.
Furthermore, predicates (i.e., functions that return SBool
) built out of
these types can also be:
- proven correct via an external SMT solver (the
prove
function) - checked for satisfiability (the
sat
,allSat
functions) - used in synthesis (the
sat
function with existentials) - quick-checked
If a predicate is not valid, prove
will return a counterexample: An
assignment to inputs such that the predicate fails. The sat
function will
return a satisfying assignment, if there is one. The allSat
function returns
all satisfying assignments.
The sbv library uses third-party SMT solvers via the standard SMT-Lib interface: http://smtlib.cs.uiowa.edu/
The SBV library is designed to work with any SMT-Lib compliant SMT-solver. Currently, we support the following SMT-Solvers out-of-the box:
- ABC from University of Berkeley: http://www.eecs.berkeley.edu/~alanmi/abc/
- CVC4, and CVC5 from Stanford University and the University of Iowa. https://cvc4.github.io/ and https://cvc5.github.io
- Boolector from Johannes Kepler University: http://fmv.jku.at/boolector/ and its successor Bitwuzla from Stanford university: https://github.com/bitwuzla/bitwuzla
- MathSAT from Fondazione Bruno Kessler and DISI-University of Trento: http://mathsat.fbk.eu/
- Yices from SRI: http://yices.csl.sri.com/
- DReal from CMU: http://dreal.github.io/
- Z3 from Microsoft: http://github.com/Z3Prover/z3/wiki
SBV requires recent versions of these solvers; please see the file
SMTSolverVersions.md
in the source distribution for specifics.
SBV also allows calling these solvers in parallel, either getting results from multiple solvers
or returning the fastest one. (See proveWithAll
, proveWithAny
, etc.)
Support for other compliant solvers can be added relatively easily, please get in touch if there is a solver you'd like to see included.
Synopsis
- type SBool = SBV Bool
- sTrue :: SBool
- sFalse :: SBool
- sNot :: SBool -> SBool
- (.&&) :: SBool -> SBool -> SBool
- (.||) :: SBool -> SBool -> SBool
- (.<+>) :: SBool -> SBool -> SBool
- (.~&) :: SBool -> SBool -> SBool
- (.~|) :: SBool -> SBool -> SBool
- (.=>) :: SBool -> SBool -> SBool
- (.<=>) :: SBool -> SBool -> SBool
- fromBool :: Bool -> SBool
- oneIf :: (Ord a, Num a, SymVal a) => SBool -> SBV a
- sAnd :: [SBool] -> SBool
- sOr :: [SBool] -> SBool
- sAny :: (a -> SBool) -> [a] -> SBool
- sAll :: (a -> SBool) -> [a] -> SBool
- type SWord8 = SBV Word8
- type SWord16 = SBV Word16
- type SWord32 = SBV Word32
- type SWord64 = SBV Word64
- type SWord (n :: Nat) = SBV (WordN n)
- data WordN (n :: Nat)
- type SInt8 = SBV Int8
- type SInt16 = SBV Int16
- type SInt32 = SBV Int32
- type SInt64 = SBV Int64
- type SInt (n :: Nat) = SBV (IntN n)
- data IntN (n :: Nat)
- type family BVIsNonZero (arg :: Nat) :: Constraint where ...
- type family FromSized (t :: Type) :: Type where ...
- type family ToSized (t :: Type) :: Type where ...
- fromSized :: FromSizedBV a => a -> FromSized a
- toSized :: ToSizedBV a => a -> ToSized a
- type SInteger = SBV Integer
- type family ValidFloat (eb :: Nat) (sb :: Nat) :: Constraint where ...
- type SFloat = SBV Float
- type SDouble = SBV Double
- type SFloatingPoint (eb :: Nat) (sb :: Nat) = SBV (FloatingPoint eb sb)
- data FloatingPoint (eb :: Nat) (sb :: Nat)
- type SFPHalf = SBV FPHalf
- type FPHalf = FloatingPoint 5 11
- type SFPBFloat = SBV FPBFloat
- type FPBFloat = FloatingPoint 8 8
- type SFPSingle = SBV FPSingle
- type FPSingle = FloatingPoint 8 24
- type SFPDouble = SBV FPDouble
- type FPDouble = FloatingPoint 11 53
- type SFPQuad = SBV FPQuad
- type FPQuad = FloatingPoint 15 113
- type SRational = SBV Rational
- type SReal = SBV AlgReal
- data AlgReal
- sRealToSInteger :: SReal -> SInteger
- algRealToRational :: AlgReal -> RationalCV
- data RealPoint a
- = OpenPoint a
- | ClosedPoint a
- realPoint :: RealPoint a -> a
- data RationalCV
- type SChar = SBV Char
- type SString = SBV String
- type SList a = SBV [a]
- class SymTuple a
- type STuple a b = SBV (a, b)
- type STuple2 a b = SBV (a, b)
- type STuple3 a b c = SBV (a, b, c)
- type STuple4 a b c d = SBV (a, b, c, d)
- type STuple5 a b c d e = SBV (a, b, c, d, e)
- type STuple6 a b c d e f = SBV (a, b, c, d, e, f)
- type STuple7 a b c d e f g = SBV (a, b, c, d, e, f, g)
- type STuple8 a b c d e f g h = SBV (a, b, c, d, e, f, g, h)
- type SMaybe a = SBV (Maybe a)
- type SEither a b = SBV (Either a b)
- data RCSet a
- = RegularSet (Set a)
- | ComplementSet (Set a)
- type SSet a = SBV (RCSet a)
- class SymArray array where
- newArray_ :: (SymArray array, HasKind a, HasKind b) => Maybe (SBV b) -> Symbolic (array a b)
- newArray :: (SymArray array, HasKind a, HasKind b) => String -> Maybe (SBV b) -> Symbolic (array a b)
- data SArray a b
- sBool :: String -> Symbolic SBool
- sBool_ :: Symbolic SBool
- sWord8 :: String -> Symbolic SWord8
- sWord8_ :: Symbolic SWord8
- sWord16 :: String -> Symbolic SWord16
- sWord16_ :: Symbolic SWord16
- sWord32 :: String -> Symbolic SWord32
- sWord32_ :: Symbolic SWord32
- sWord64 :: String -> Symbolic SWord64
- sWord64_ :: Symbolic SWord64
- sWord :: (KnownNat n, BVIsNonZero n) => String -> Symbolic (SWord n)
- sWord_ :: (KnownNat n, BVIsNonZero n) => Symbolic (SWord n)
- sInt8 :: String -> Symbolic SInt8
- sInt8_ :: Symbolic SInt8
- sInt16 :: String -> Symbolic SInt16
- sInt16_ :: Symbolic SInt16
- sInt32 :: String -> Symbolic SInt32
- sInt32_ :: Symbolic SInt32
- sInt64 :: String -> Symbolic SInt64
- sInt64_ :: Symbolic SInt64
- sInt :: (KnownNat n, BVIsNonZero n) => String -> Symbolic (SInt n)
- sInt_ :: (KnownNat n, BVIsNonZero n) => Symbolic (SInt n)
- sInteger :: String -> Symbolic SInteger
- sInteger_ :: Symbolic SInteger
- sReal :: String -> Symbolic SReal
- sReal_ :: Symbolic SReal
- sRational :: String -> Symbolic SRational
- sRational_ :: Symbolic SRational
- sFloat :: String -> Symbolic SFloat
- sFloat_ :: Symbolic SFloat
- sDouble :: String -> Symbolic SDouble
- sDouble_ :: Symbolic SDouble
- sFloatingPoint :: ValidFloat eb sb => String -> Symbolic (SFloatingPoint eb sb)
- sFloatingPoint_ :: ValidFloat eb sb => Symbolic (SFloatingPoint eb sb)
- sFPHalf :: String -> Symbolic SFPHalf
- sFPHalf_ :: Symbolic SFPHalf
- sFPBFloat :: String -> Symbolic SFPBFloat
- sFPBFloat_ :: Symbolic SFPBFloat
- sFPSingle :: String -> Symbolic SFPSingle
- sFPSingle_ :: Symbolic SFPSingle
- sFPDouble :: String -> Symbolic SFPDouble
- sFPDouble_ :: Symbolic SFPDouble
- sFPQuad :: String -> Symbolic SFPQuad
- sFPQuad_ :: Symbolic SFPQuad
- sChar :: String -> Symbolic SChar
- sChar_ :: Symbolic SChar
- sString :: String -> Symbolic SString
- sString_ :: Symbolic SString
- sList :: SymVal a => String -> Symbolic (SList a)
- sList_ :: SymVal a => Symbolic (SList a)
- sTuple :: (SymTuple tup, SymVal tup) => String -> Symbolic (SBV tup)
- sTuple_ :: (SymTuple tup, SymVal tup) => Symbolic (SBV tup)
- sEither :: (SymVal a, SymVal b) => String -> Symbolic (SEither a b)
- sEither_ :: (SymVal a, SymVal b) => Symbolic (SEither a b)
- sMaybe :: SymVal a => String -> Symbolic (SMaybe a)
- sMaybe_ :: SymVal a => Symbolic (SMaybe a)
- sSet :: (Ord a, SymVal a) => String -> Symbolic (SSet a)
- sSet_ :: (Ord a, SymVal a) => Symbolic (SSet a)
- sBools :: [String] -> Symbolic [SBool]
- sWord8s :: [String] -> Symbolic [SWord8]
- sWord16s :: [String] -> Symbolic [SWord16]
- sWord32s :: [String] -> Symbolic [SWord32]
- sWord64s :: [String] -> Symbolic [SWord64]
- sWords :: (KnownNat n, BVIsNonZero n) => [String] -> Symbolic [SWord n]
- sInt8s :: [String] -> Symbolic [SInt8]
- sInt16s :: [String] -> Symbolic [SInt16]
- sInt32s :: [String] -> Symbolic [SInt32]
- sInt64s :: [String] -> Symbolic [SInt64]
- sInts :: (KnownNat n, BVIsNonZero n) => [String] -> Symbolic [SInt n]
- sIntegers :: [String] -> Symbolic [SInteger]
- sReals :: [String] -> Symbolic [SReal]
- sRationals :: [String] -> Symbolic [SRational]
- sFloats :: [String] -> Symbolic [SFloat]
- sDoubles :: [String] -> Symbolic [SDouble]
- sFloatingPoints :: ValidFloat eb sb => [String] -> Symbolic [SFloatingPoint eb sb]
- sFPHalfs :: [String] -> Symbolic [SFPHalf]
- sFPBFloats :: [String] -> Symbolic [SFPBFloat]
- sFPSingles :: [String] -> Symbolic [SFPSingle]
- sFPDoubles :: [String] -> Symbolic [SFPDouble]
- sFPQuads :: [String] -> Symbolic [SFPQuad]
- sChars :: [String] -> Symbolic [SChar]
- sStrings :: [String] -> Symbolic [SString]
- sLists :: SymVal a => [String] -> Symbolic [SList a]
- sTuples :: (SymTuple tup, SymVal tup) => [String] -> Symbolic [SBV tup]
- sEithers :: (SymVal a, SymVal b) => [String] -> Symbolic [SEither a b]
- sMaybes :: SymVal a => [String] -> Symbolic [SMaybe a]
- sSets :: (Ord a, SymVal a) => [String] -> Symbolic [SSet a]
- class EqSymbolic a where
- class (Mergeable a, EqSymbolic a) => OrdSymbolic a where
- class Equality a where
- class Mergeable a where
- ite :: Mergeable a => SBool -> a -> a -> a
- iteLazy :: Mergeable a => SBool -> a -> a -> a
- class (SymVal a, Num a, Bits a, Integral a) => SIntegral a
- class SDivisible a where
- sFromIntegral :: forall a b. (Integral a, HasKind a, Num a, SymVal a, HasKind b, Num b, SymVal b) => SBV a -> SBV b
- sShiftLeft :: (SIntegral a, SIntegral b) => SBV a -> SBV b -> SBV a
- sShiftRight :: (SIntegral a, SIntegral b) => SBV a -> SBV b -> SBV a
- sRotateLeft :: (SIntegral a, SIntegral b) => SBV a -> SBV b -> SBV a
- sBarrelRotateLeft :: (SFiniteBits a, SFiniteBits b) => SBV a -> SBV b -> SBV a
- sRotateRight :: (SIntegral a, SIntegral b) => SBV a -> SBV b -> SBV a
- sBarrelRotateRight :: (SFiniteBits a, SFiniteBits b) => SBV a -> SBV b -> SBV a
- sSignedShiftArithRight :: (SFiniteBits a, SIntegral b) => SBV a -> SBV b -> SBV a
- class (Ord a, SymVal a, Num a, Bits a) => SFiniteBits a where
- sFiniteBitSize :: SBV a -> Int
- lsb :: SBV a -> SBool
- msb :: SBV a -> SBool
- blastBE :: SBV a -> [SBool]
- blastLE :: SBV a -> [SBool]
- fromBitsBE :: [SBool] -> SBV a
- fromBitsLE :: [SBool] -> SBV a
- sTestBit :: SBV a -> Int -> SBool
- sExtractBits :: SBV a -> [Int] -> [SBool]
- sPopCount :: SBV a -> SWord8
- setBitTo :: SBV a -> Int -> SBool -> SBV a
- fullAdder :: SBV a -> SBV a -> (SBool, SBV a)
- fullMultiplier :: SBV a -> SBV a -> (SBV a, SBV a)
- sCountLeadingZeros :: SBV a -> SWord8
- sCountTrailingZeros :: SBV a -> SWord8
- bvExtract :: forall i j n bv proxy. (KnownNat n, BVIsNonZero n, SymVal (bv n), KnownNat i, KnownNat j, (i + 1) <= n, j <= i, BVIsNonZero ((i - j) + 1)) => proxy i -> proxy j -> SBV (bv n) -> SBV (bv ((i - j) + 1))
- (#) :: (KnownNat n, BVIsNonZero n, SymVal (bv n), KnownNat m, BVIsNonZero m, SymVal (bv m)) => SBV (bv n) -> SBV (bv m) -> SBV (bv (n + m))
- zeroExtend :: forall n m bv. (KnownNat n, BVIsNonZero n, SymVal (bv n), KnownNat m, BVIsNonZero m, SymVal (bv m), (n + 1) <= m, SIntegral (bv (m - n)), BVIsNonZero (m - n)) => SBV (bv n) -> SBV (bv m)
- signExtend :: forall n m bv. (KnownNat n, BVIsNonZero n, SymVal (bv n), KnownNat m, BVIsNonZero m, SymVal (bv m), (n + 1) <= m, SFiniteBits (bv n), SIntegral (bv (m - n)), BVIsNonZero (m - n)) => SBV (bv n) -> SBV (bv m)
- bvDrop :: forall i n m bv proxy. (KnownNat n, BVIsNonZero n, KnownNat i, (i + 1) <= n, ((i + m) - n) <= 0, BVIsNonZero (n - i)) => proxy i -> SBV (bv n) -> SBV (bv m)
- bvTake :: forall i n bv proxy. (KnownNat n, BVIsNonZero n, KnownNat i, BVIsNonZero i, i <= n) => proxy i -> SBV (bv n) -> SBV (bv i)
- class ByteConverter a where
- (.^) :: (Mergeable b, Num b, SIntegral e) => b -> SBV e -> b
- class (SymVal a, RealFloat a) => IEEEFloating a where
- fpAbs :: SBV a -> SBV a
- fpNeg :: SBV a -> SBV a
- fpAdd :: SRoundingMode -> SBV a -> SBV a -> SBV a
- fpSub :: SRoundingMode -> SBV a -> SBV a -> SBV a
- fpMul :: SRoundingMode -> SBV a -> SBV a -> SBV a
- fpDiv :: SRoundingMode -> SBV a -> SBV a -> SBV a
- fpFMA :: SRoundingMode -> SBV a -> SBV a -> SBV a -> SBV a
- fpSqrt :: SRoundingMode -> SBV a -> SBV a
- fpRem :: SBV a -> SBV a -> SBV a
- fpRoundToIntegral :: SRoundingMode -> SBV a -> SBV a
- fpMin :: SBV a -> SBV a -> SBV a
- fpMax :: SBV a -> SBV a -> SBV a
- fpIsEqualObject :: SBV a -> SBV a -> SBool
- fpIsNormal :: SBV a -> SBool
- fpIsSubnormal :: SBV a -> SBool
- fpIsZero :: SBV a -> SBool
- fpIsInfinite :: SBV a -> SBool
- fpIsNaN :: SBV a -> SBool
- fpIsNegative :: SBV a -> SBool
- fpIsPositive :: SBV a -> SBool
- fpIsNegativeZero :: SBV a -> SBool
- fpIsPositiveZero :: SBV a -> SBool
- fpIsPoint :: SBV a -> SBool
- data RoundingMode
- type SRoundingMode = SBV RoundingMode
- nan :: Floating a => a
- infinity :: Floating a => a
- sNaN :: (Floating a, SymVal a) => SBV a
- sInfinity :: (Floating a, SymVal a) => SBV a
- sRoundNearestTiesToEven :: SRoundingMode
- sRoundNearestTiesToAway :: SRoundingMode
- sRoundTowardPositive :: SRoundingMode
- sRoundTowardNegative :: SRoundingMode
- sRoundTowardZero :: SRoundingMode
- sRNE :: SRoundingMode
- sRNA :: SRoundingMode
- sRTP :: SRoundingMode
- sRTN :: SRoundingMode
- sRTZ :: SRoundingMode
- class SymVal a => IEEEFloatConvertible a where
- fromSFloat :: SRoundingMode -> SFloat -> SBV a
- toSFloat :: SRoundingMode -> SBV a -> SFloat
- fromSDouble :: SRoundingMode -> SDouble -> SBV a
- toSDouble :: SRoundingMode -> SBV a -> SDouble
- fromSFloatingPoint :: ValidFloat eb sb => SRoundingMode -> SFloatingPoint eb sb -> SBV a
- toSFloatingPoint :: ValidFloat eb sb => SRoundingMode -> SBV a -> SFloatingPoint eb sb
- sFloatAsSWord32 :: SFloat -> SWord32
- sWord32AsSFloat :: SWord32 -> SFloat
- sDoubleAsSWord64 :: SDouble -> SWord64
- sWord64AsSDouble :: SWord64 -> SDouble
- sFloatingPointAsSWord :: forall eb sb. (ValidFloat eb sb, KnownNat (eb + sb), BVIsNonZero (eb + sb)) => SFloatingPoint eb sb -> SWord (eb + sb)
- sWordAsSFloatingPoint :: forall eb sb. (KnownNat (eb + sb), BVIsNonZero (eb + sb), ValidFloat eb sb) => SWord (eb + sb) -> SFloatingPoint eb sb
- blastSFloat :: SFloat -> (SBool, [SBool], [SBool])
- blastSDouble :: SDouble -> (SBool, [SBool], [SBool])
- blastSFloatingPoint :: forall eb sb. (ValidFloat eb sb, KnownNat (eb + sb), BVIsNonZero (eb + sb)) => SFloatingPoint eb sb -> (SBool, [SBool], [SBool])
- crack :: SBV a -> String
- mkSymbolicEnumeration :: Name -> Q [Dec]
- mkUninterpretedSort :: Name -> Q [Dec]
- class Uninterpreted a where
- uninterpret :: String -> a
- cgUninterpret :: String -> [String] -> a -> a
- sbvUninterpret :: Maybe ([String], a) -> String -> a
- sym :: String -> a
- addAxiom :: SolverContext m => String -> [String] -> m ()
- addSMTDefinition :: SolverContext m => String -> [String] -> m ()
- type Predicate = Symbolic SBool
- type Goal = Symbolic ()
- type Provable = MProvable IO
- universal_ :: Provable a => a -> Symbolic SBool
- universal :: Provable a => [String] -> a -> Symbolic SBool
- existential_ :: Provable a => a -> Symbolic SBool
- existential :: Provable a => [String] -> a -> Symbolic SBool
- prove :: Provable a => a -> IO ThmResult
- proveWith :: Provable a => SMTConfig -> a -> IO ThmResult
- dprove :: Provable a => a -> IO ThmResult
- dproveWith :: Provable a => SMTConfig -> a -> IO ThmResult
- sat :: Provable a => a -> IO SatResult
- satWith :: Provable a => SMTConfig -> a -> IO SatResult
- dsat :: Provable a => a -> IO SatResult
- dsatWith :: Provable a => SMTConfig -> a -> IO SatResult
- allSat :: Provable a => a -> IO AllSatResult
- allSatWith :: Provable a => SMTConfig -> a -> IO AllSatResult
- optimize :: Provable a => OptimizeStyle -> a -> IO OptimizeResult
- optimizeWith :: Provable a => SMTConfig -> OptimizeStyle -> a -> IO OptimizeResult
- isVacuous :: Provable a => a -> IO Bool
- isVacuousWith :: Provable a => SMTConfig -> a -> IO Bool
- isTheorem :: Provable a => a -> IO Bool
- isTheoremWith :: Provable a => SMTConfig -> a -> IO Bool
- isSatisfiable :: Provable a => a -> IO Bool
- isSatisfiableWith :: Provable a => SMTConfig -> a -> IO Bool
- proveWithAll :: Provable a => [SMTConfig] -> a -> IO [(Solver, NominalDiffTime, ThmResult)]
- proveWithAny :: Provable a => [SMTConfig] -> a -> IO (Solver, NominalDiffTime, ThmResult)
- satWithAll :: Provable a => [SMTConfig] -> a -> IO [(Solver, NominalDiffTime, SatResult)]
- proveConcurrentWithAny :: Provable a => SMTConfig -> [Query b] -> a -> IO (Solver, NominalDiffTime, ThmResult)
- proveConcurrentWithAll :: Provable a => SMTConfig -> [Query b] -> a -> IO [(Solver, NominalDiffTime, ThmResult)]
- satConcurrentWithAny :: Provable a => SMTConfig -> [Query b] -> a -> IO (Solver, NominalDiffTime, SatResult)
- satConcurrentWithAll :: Provable a => SMTConfig -> [Query b] -> a -> IO [(Solver, NominalDiffTime, SatResult)]
- satWithAny :: Provable a => [SMTConfig] -> a -> IO (Solver, NominalDiffTime, SatResult)
- generateSMTBenchmark :: (MonadIO m, MProvable m a) => Bool -> a -> m String
- solve :: [SBool] -> Symbolic SBool
- constrain :: SolverContext m => SBool -> m ()
- softConstrain :: SolverContext m => SBool -> m ()
- namedConstraint :: SolverContext m => String -> SBool -> m ()
- constrainWithAttribute :: SolverContext m => [(String, String)] -> SBool -> m ()
- pbAtMost :: [SBool] -> Int -> SBool
- pbAtLeast :: [SBool] -> Int -> SBool
- pbExactly :: [SBool] -> Int -> SBool
- pbLe :: [(Int, SBool)] -> Int -> SBool
- pbGe :: [(Int, SBool)] -> Int -> SBool
- pbEq :: [(Int, SBool)] -> Int -> SBool
- pbMutexed :: [SBool] -> SBool
- pbStronglyMutexed :: [SBool] -> SBool
- sAssert :: HasKind a => Maybe CallStack -> String -> SBool -> SBV a -> SBV a
- isSafe :: SafeResult -> Bool
- class ExtractIO m => SExecutable m a
- sName_ :: SExecutable IO a => a -> Symbolic ()
- sName :: SExecutable IO a => [String] -> a -> Symbolic ()
- safe :: SExecutable IO a => a -> IO [SafeResult]
- safeWith :: SExecutable IO a => SMTConfig -> a -> IO [SafeResult]
- sbvQuickCheck :: Symbolic SBool -> IO Bool
- data OptimizeStyle
- = Lexicographic
- | Independent
- | Pareto (Maybe Int)
- data Objective a
- class Metric a where
- type MetricSpace a :: Type
- toMetricSpace :: SBV a -> SBV (MetricSpace a)
- fromMetricSpace :: SBV (MetricSpace a) -> SBV a
- msMinimize :: (MonadSymbolic m, SolverContext m) => String -> SBV a -> m ()
- msMaximize :: (MonadSymbolic m, SolverContext m) => String -> SBV a -> m ()
- minimize :: Metric a => String -> SBV a -> Symbolic ()
- maximize :: Metric a => String -> SBV a -> Symbolic ()
- assertWithPenalty :: String -> SBool -> Penalty -> Symbolic ()
- data Penalty
- data ExtCV
- data GeneralizedCV
- newtype ThmResult = ThmResult SMTResult
- newtype SatResult = SatResult SMTResult
- data AllSatResult = AllSatResult {}
- newtype SafeResult = SafeResult (Maybe String, String, SMTResult)
- data OptimizeResult
- data SMTResult
- data SMTReasonUnknown
- observe :: SymVal a => String -> SBV a -> SBV a
- observeIf :: SymVal a => (a -> Bool) -> String -> SBV a -> SBV a
- sObserve :: SymVal a => String -> SBV a -> Symbolic ()
- class SatModel a where
- class Modelable a where
- modelExists :: a -> Bool
- getModelAssignment :: SatModel b => a -> Either String (Bool, b)
- getModelDictionary :: a -> Map String CV
- getModelValue :: SymVal b => String -> a -> Maybe b
- getModelUninterpretedValue :: String -> a -> Maybe String
- extractModel :: SatModel b => a -> Maybe b
- getModelObjectives :: a -> Map String GeneralizedCV
- getModelObjectiveValue :: String -> a -> Maybe GeneralizedCV
- getModelUIFuns :: a -> Map String (SBVType, ([([CV], CV)], CV))
- getModelUIFunValue :: String -> a -> Maybe (SBVType, ([([CV], CV)], CV))
- displayModels :: SatModel a => ([(Bool, a)] -> [(Bool, a)]) -> (Int -> (Bool, a) -> IO ()) -> AllSatResult -> IO Int
- extractModels :: SatModel a => AllSatResult -> [a]
- getModelDictionaries :: AllSatResult -> [Map String CV]
- getModelValues :: SymVal b => String -> AllSatResult -> [Maybe b]
- getModelUninterpretedValues :: String -> AllSatResult -> [Maybe String]
- data SMTConfig = SMTConfig {
- verbose :: Bool
- timing :: Timing
- printBase :: Int
- printRealPrec :: Int
- crackNum :: Bool
- satCmd :: String
- allSatMaxModelCount :: Maybe Int
- allSatPrintAlong :: Bool
- satTrackUFs :: Bool
- isNonModelVar :: String -> Bool
- validateModel :: Bool
- optimizeValidateConstraints :: Bool
- transcript :: Maybe FilePath
- smtLibVersion :: SMTLibVersion
- dsatPrecision :: Maybe Double
- solver :: SMTSolver
- extraArgs :: [String]
- allowQuantifiedQueries :: Bool
- roundingMode :: RoundingMode
- solverSetOptions :: [SMTOption]
- ignoreExitCode :: Bool
- redirectVerbose :: Maybe FilePath
- data Timing
- data SMTLibVersion = SMTLib2
- data Solver
- data SMTSolver = SMTSolver {
- name :: Solver
- executable :: String
- preprocess :: String -> String
- options :: SMTConfig -> [String]
- engine :: SMTEngine
- capabilities :: SolverCapabilities
- boolector :: SMTConfig
- bitwuzla :: SMTConfig
- cvc4 :: SMTConfig
- cvc5 :: SMTConfig
- yices :: SMTConfig
- dReal :: SMTConfig
- z3 :: SMTConfig
- mathSAT :: SMTConfig
- abc :: SMTConfig
- defaultSolverConfig :: Solver -> SMTConfig
- defaultSMTCfg :: SMTConfig
- defaultDeltaSMTCfg :: SMTConfig
- sbvCheckSolverInstallation :: SMTConfig -> IO Bool
- getAvailableSolvers :: IO [SMTConfig]
- setLogic :: SolverContext m => Logic -> m ()
- data Logic
- setOption :: SolverContext m => SMTOption -> m ()
- setInfo :: SolverContext m => String -> [String] -> m ()
- setTimeOut :: SolverContext m => Integer -> m ()
- data SBVException = SBVException {
- sbvExceptionDescription :: String
- sbvExceptionSent :: Maybe String
- sbvExceptionExpected :: Maybe String
- sbvExceptionReceived :: Maybe String
- sbvExceptionStdOut :: Maybe String
- sbvExceptionStdErr :: Maybe String
- sbvExceptionExitCode :: Maybe ExitCode
- sbvExceptionConfig :: SMTConfig
- sbvExceptionReason :: Maybe [String]
- sbvExceptionHint :: Maybe [String]
- data SBV a
- class HasKind a where
- kindOf :: a -> Kind
- hasSign :: a -> Bool
- intSizeOf :: a -> Int
- isBoolean :: a -> Bool
- isBounded :: a -> Bool
- isReal :: a -> Bool
- isFloat :: a -> Bool
- isDouble :: a -> Bool
- isRational :: a -> Bool
- isFP :: a -> Bool
- isUnbounded :: a -> Bool
- isUserSort :: a -> Bool
- isChar :: a -> Bool
- isString :: a -> Bool
- isList :: a -> Bool
- isSet :: a -> Bool
- isTuple :: a -> Bool
- isMaybe :: a -> Bool
- isEither :: a -> Bool
- showType :: a -> String
- data Kind
- class (HasKind a, Typeable a) => SymVal a
- sbvForall :: SymVal a => String -> Symbolic (SBV a)
- sbvForall_ :: SymVal a => Symbolic (SBV a)
- mkForallVars :: SymVal a => Int -> Symbolic [SBV a]
- sbvExists :: SymVal a => String -> Symbolic (SBV a)
- sbvExists_ :: SymVal a => Symbolic (SBV a)
- mkExistVars :: SymVal a => Int -> Symbolic [SBV a]
- free :: SymVal a => String -> Symbolic (SBV a)
- free_ :: SymVal a => Symbolic (SBV a)
- mkFreeVars :: SymVal a => Int -> Symbolic [SBV a]
- symbolic :: SymVal a => String -> Symbolic (SBV a)
- symbolics :: SymVal a => [String] -> Symbolic [SBV a]
- literal :: SymVal a => a -> SBV a
- unliteral :: SymVal a => SBV a -> Maybe a
- fromCV :: SymVal a => CV -> a
- isConcrete :: SymVal a => SBV a -> Bool
- isSymbolic :: SymVal a => SBV a -> Bool
- isConcretely :: SymVal a => SBV a -> (a -> Bool) -> Bool
- mkSymVal :: SymVal a => VarContext -> Maybe String -> Symbolic (SBV a)
- class MonadIO m => MonadSymbolic m where
- symbolicEnv :: m State
- type Symbolic = SymbolicT IO
- data SymbolicT m a
- label :: SymVal a => String -> SBV a -> SBV a
- output :: Outputtable a => a -> Symbolic a
- runSMT :: Symbolic a -> IO a
- runSMTWith :: SMTConfig -> Symbolic a -> IO a
- module Data.Bits
- module Data.Word
- module Data.Int
- module Data.Ratio
Documentation
The SBV library is really two things:
- A framework for writing symbolic programs in Haskell, i.e., programs operating on symbolic values along with the usual concrete counterparts.
- A framework for proving properties of such programs using SMT solvers.
The programming goal of SBV is to provide a seamless experience, i.e., let people program
in the usual Haskell style without distractions of symbolic coding. While Haskell helps
in some aspects (the Num
and Bits
classes simplify coding), it makes life harder
in others. For instance, if-then-else
only takes Bool
as a test in Haskell, and
comparisons (>
etc.) only return Bool
s. Clearly we would like these values to be
symbolic (i.e., SBool
), thus stopping us from using some native Haskell constructs.
When symbolic versions of operators are needed, they are typically obtained by prepending a dot,
for instance ==
becomes .==
. Care has been taken to make the transition painless. In
particular, any Haskell program you build out of symbolic components is fully concretely
executable within Haskell, without the need for any custom interpreters. (They are truly
Haskell programs, not AST's built out of pieces of syntax.) This provides for an integrated
feel of the system, one of the original design goals for SBV.
Incremental query mode: SBV provides a wide variety of ways to utilize SMT-solvers, without requiring the user to deal with the solvers themselves. While this mode is convenient, advanced users might need access to the underlying solver at a lower level. For such use cases, SBV allows users to have an interactive session: The user can issue commands to the solver, inspect the values/results, and formulate new constraints. This advanced feature is available through the Data.SBV.Control module, where most SMTLib features are made available via a typed-API.
Symbolic types
Booleans
Boolean values and functions
oneIf :: (Ord a, Num a, SymVal a) => SBool -> SBV a Source #
Returns 1 if the boolean is sTrue
, otherwise 0.
Logical aggregations
Bit-vectors
Unsigned bit-vectors
data WordN (n :: Nat) Source #
An unsigned bit-vector carrying its size info
Instances
Signed bit-vectors
A signed bit-vector carrying its size info
Instances
Converting between fixed-size and arbitrary bitvectors
type family BVIsNonZero (arg :: Nat) :: Constraint where ... Source #
Type family to create the appropriate non-zero constraint
BVIsNonZero 0 = TypeError BVZeroWidth | |
BVIsNonZero _ = () |
type family FromSized (t :: Type) :: Type where ... Source #
Capture the correspondence between sized and fixed-sized BVs
FromSized (WordN 8) = Word8 | |
FromSized (WordN 16) = Word16 | |
FromSized (WordN 32) = Word32 | |
FromSized (WordN 64) = Word64 | |
FromSized (IntN 8) = Int8 | |
FromSized (IntN 16) = Int16 | |
FromSized (IntN 32) = Int32 | |
FromSized (IntN 64) = Int64 | |
FromSized (SWord 8) = SWord8 | |
FromSized (SWord 16) = SWord16 | |
FromSized (SWord 32) = SWord32 | |
FromSized (SWord 64) = SWord64 | |
FromSized (SInt 8) = SInt8 | |
FromSized (SInt 16) = SInt16 | |
FromSized (SInt 32) = SInt32 | |
FromSized (SInt 64) = SInt64 |
type family ToSized (t :: Type) :: Type where ... Source #
Capture the correspondence between fixed-sized and sized BVs
ToSized Word8 = WordN 8 | |
ToSized Word16 = WordN 16 | |
ToSized Word32 = WordN 32 | |
ToSized Word64 = WordN 64 | |
ToSized Int8 = IntN 8 | |
ToSized Int16 = IntN 16 | |
ToSized Int32 = IntN 32 | |
ToSized Int64 = IntN 64 | |
ToSized SWord8 = SWord 8 | |
ToSized SWord16 = SWord 16 | |
ToSized SWord32 = SWord 32 | |
ToSized SWord64 = SWord 64 | |
ToSized SInt8 = SInt 8 | |
ToSized SInt16 = SInt 16 | |
ToSized SInt32 = SInt 32 | |
ToSized SInt64 = SInt 64 |
Unbounded integers
The SBV library supports unbounded signed integers with the type SInteger
, which are not subject to
overflow/underflow as it is the case with the bounded types, such as SWord8
, SInt16
, etc. However,
some bit-vector based operations are not supported for the SInteger
type while in the verification mode. That
is, you can use these operations on SInteger
values during normal programming/simulation.
but the SMT translation will not support these operations since there corresponding operations are not supported in SMT-Lib.
Note that this should rarely be a problem in practice, as these operations are mostly meaningful on fixed-size
bit-vectors. The operations that are restricted to bounded word/int sizes are:
- Rotations and shifts:
rotateL
,rotateR
,shiftL
,shiftR
- Bitwise logical ops:
.&.
,.|.
,xor
,complement
- Extraction and concatenation:
bvExtract
,#
,zeroExtend
,signExtend
,bvDrop
, andbvTake
Usual arithmetic (+
, -
, *
, sQuotRem
, sQuot
, sRem
, sDivMod
, sDiv
, sMod
) and logical operations (.<
, .<=
, .>
, .>=
, .==
, ./=
) operations are
supported for SInteger
fully, both in programming and verification modes.
Floating point numbers
Floating point numbers are defined by the IEEE-754 standard; and correspond to Haskell's
Float
and Double
types. For SMT support with floating-point numbers, see the paper
by Rummer and Wahl: http://www.philipp.ruemmer.org/publications/smt-fpa.pdf.
type family ValidFloat (eb :: Nat) (sb :: Nat) :: Constraint where ... Source #
A valid float has restrictions on eb/sb values. NB. In the below encoding, I found that CPP is very finicky about substitution of the machine-dependent macros. If you try to put the conditionals in the same line, it fails to substitute for some reason. Hence the awkward spacing. Filed this as a bug report for CPPHS at https://github.com/malcolmwallace/cpphs/issues/25.
ValidFloat (eb :: Nat) (sb :: Nat) = (KnownNat eb, KnownNat sb, If ((((eb `CmpNat` 2) == 'EQ) || ((eb `CmpNat` 2) == 'GT)) && ((((eb `CmpNat` 61) == 'EQ) || ((eb `CmpNat` 61) == 'LT)) && ((((sb `CmpNat` 2) == 'EQ) || ((sb `CmpNat` 2) == 'GT)) && (((sb `CmpNat` 4611686018427387902) == 'EQ) || ((sb `CmpNat` 4611686018427387902) == 'LT))))) (() :: Constraint) (TypeError (InvalidFloat eb sb))) |
type SFloatingPoint (eb :: Nat) (sb :: Nat) = SBV (FloatingPoint eb sb) Source #
A symbolic arbitrary precision floating point value
data FloatingPoint (eb :: Nat) (sb :: Nat) Source #
A floating point value, indexed by its exponent and significand sizes.
An IEEE SP is FloatingPoint 8 24
DP is FloatingPoint 11 53
etc.
Instances
type FPHalf = FloatingPoint 5 11 Source #
Abbreviation for IEEE half precision float, bit width 16 = 5 + 11.
type FPBFloat = FloatingPoint 8 8 Source #
Abbreviation for brain-float precision float, bit width 16 = 8 + 8.
type FPSingle = FloatingPoint 8 24 Source #
Abbreviation for IEEE single precision float, bit width 32 = 8 + 24.
type FPDouble = FloatingPoint 11 53 Source #
Abbreviation for IEEE double precision float, bit width 64 = 11 + 53.
type FPQuad = FloatingPoint 15 113 Source #
Abbreviation for IEEE quadruble precision float, bit width 128 = 15 + 113.
Rationals
Algebraic reals
Algebraic reals are roots of single-variable polynomials with rational coefficients. (See
http://en.wikipedia.org/wiki/Algebraic_number.) Note that algebraic reals are infinite
precision numbers, but they do not cover all real numbers. (In particular, they cannot
represent transcendentals.) Some irrational numbers are algebraic (such as sqrt 2
), while
others are not (such as pi and e).
SBV can deal with real numbers just fine, since the theory of reals is decidable. (See http://smtlib.cs.uiowa.edu/theories-Reals.shtml.) In addition, by leveraging backend solver capabilities, SBV can also represent and solve non-linear equations involving real-variables. (For instance, the Z3 SMT solver, supports polynomial constraints on reals starting with v4.0.)
Algebraic reals. Note that the representation is left abstract. We represent rational results explicitly, while the roots-of-polynomials are represented implicitly by their defining equation
AlgRational Bool Rational | bool says it's exact (i.e., SMT-solver did not return it with ? at the end.) |
AlgPolyRoot (Integer, AlgRealPoly) (Maybe String) | which root of this polynomial and an approximate decimal representation with given precision, if available |
AlgInterval (RealPoint Rational) (RealPoint Rational) | interval, with low and high bounds |
Instances
sRealToSInteger :: SReal -> SInteger Source #
Convert an SReal to an SInteger. That is, it computes the
largest integer n
that satisfies sIntegerToSReal n <= r
essentially giving us the floor
.
For instance, 1.3
will be 1
, but -1.3
will be -2
.
Is the endpoint included in the interval?
OpenPoint a | open: i.e., doesn't include the point |
ClosedPoint a | closed: i.e., includes the point |
Instances
Eq a => Eq (RealPoint a) Source # | |
Ord a => Ord (RealPoint a) Source # | |
Defined in Data.SBV.Core.AlgReals | |
Show a => Show (RealPoint a) Source # | |
data RationalCV Source #
Conversion from internal rationals to Haskell values
RatIrreducible AlgReal | Root of a polynomial, cannot be reduced |
RatExact Rational | An exact rational |
RatApprox Rational | An approximated value |
RatInterval (RealPoint Rational) (RealPoint Rational) | Interval. Can be open/closed on both ends. |
Instances
Show RationalCV Source # | |
Defined in Data.SBV.Core.AlgReals showsPrec :: Int -> RationalCV -> ShowS # show :: RationalCV -> String # showList :: [RationalCV] -> ShowS # |
Characters, Strings and Regular Expressions
Support for characters, strings, and regular expressions (initial version contributed by Joel Burget) adds support for QF_S logic, described here: http://smtlib.cs.uiowa.edu/theories-UnicodeStrings.shtml
See Data.SBV.Char, Data.SBV.String, Data.SBV.RegExp for related functions.
type SChar = SBV Char Source #
A symbolic character. Note that this is the full unicode character set. see: http://smtlib.cs.uiowa.edu/theories-UnicodeStrings.shtml for details.
type SString = SBV String Source #
A symbolic string. Note that a symbolic string is not a list of symbolic characters,
that is, it is not the case that SString = [SChar]
, unlike what one might expect following
Haskell strings. An SString
is a symbolic value of its own, of possibly arbitrary but finite length,
and internally processed as one unit as opposed to a fixed-length list of characters.
Symbolic lists
Support for symbolic lists (initial version contributed by Joel Burget) adds support for sequence support.
See Data.SBV.List for related functions.
type SList a = SBV [a] Source #
A symbolic list of items. Note that a symbolic list is not a list of symbolic items,
that is, it is not the case that SList a = [a]
, unlike what one might expect following
haskell lists/sequences. An SList
is a symbolic value of its own, of possibly arbitrary but finite
length, and internally processed as one unit as opposed to a fixed-length list of items.
Note that lists can be nested, i.e., we do allow lists of lists of ... items.
Tuples
Tuples can be used as symbolic values. This is useful in combination with lists, for example SBV [(Integer, String)]
is a valid type. These types can be arbitrarily nested, eg SBV [(Integer, [(Char, (Integer, String))])]
. Instances of upto 8-tuples are provided.
Identify tuple like things. Note that there are no methods, just instances to control type inference
Instances
SymTuple () Source # | |
Defined in Data.SBV.Core.Model | |
SymTuple (a, b) Source # | |
Defined in Data.SBV.Core.Model | |
SymTuple (a, b, c) Source # | |
Defined in Data.SBV.Core.Model | |
SymTuple (a, b, c, d) Source # | |
Defined in Data.SBV.Core.Model | |
SymTuple (a, b, c, d, e) Source # | |
Defined in Data.SBV.Core.Model | |
SymTuple (a, b, c, d, e, f) Source # | |
Defined in Data.SBV.Core.Model | |
SymTuple (a, b, c, d, e, f, g) Source # | |
Defined in Data.SBV.Core.Model | |
SymTuple (a, b, c, d, e, f, g, h) Source # | |
Defined in Data.SBV.Core.Model |
Sum types
Sets
A RCSet
is either a regular set or a set given by its complement from the corresponding universal set.
RegularSet (Set a) | |
ComplementSet (Set a) |
Instances
Arrays of symbolic values
class SymArray array where Source #
Arrays of symbolic values
An array a b
is an array indexed by the type
, with elements of type SBV
a
.SBV
b
If a default value is supplied, then all the array elements will be initialized to this value. Otherwise, they will be left unspecified, i.e., a read from an unwritten location will produce an uninterpreted constant.
The reason for this class is rather historic. In the past, SBV provided two different kinds of
arrays: an SArray
abstraction that mapped directly to SMTLib arrays (which is still available
today), and a functional notion of arrays that used internal caching, called SFunArray
. The latter
has been removed as the code turned out to be rather tricky and hard to maintain; so we only
have one instance of this class. But end users can add their own instances, if needed.
NB. sListArray
insists on a concrete initializer, because not having one would break
referential transparency. See https://github.com/LeventErkok/sbv/issues/553 for details.
sListArray :: (HasKind a, SymVal b) => b -> [(SBV a, SBV b)] -> array a b Source #
Create a literal array
readArray :: array a b -> SBV a -> SBV b Source #
Read the array element at a
writeArray :: SymVal b => array a b -> SBV a -> SBV b -> array a b Source #
Update the element at a
to be b
mergeArrays :: SymVal b => SBV Bool -> array a b -> array a b -> array a b Source #
Merge two given arrays on the symbolic condition
Intuitively: mergeArrays cond a b = if cond then a else b
.
Merging pushes the if-then-else choice down on to elements
Instances
SymArray SArray Source # | |
Defined in Data.SBV.Core.Data newArray_ :: (MonadSymbolic m, HasKind a, HasKind b) => Maybe (SBV b) -> m (SArray a b) Source # newArray :: (MonadSymbolic m, HasKind a, HasKind b) => String -> Maybe (SBV b) -> m (SArray a b) Source # sListArray :: (HasKind a, SymVal b) => b -> [(SBV a, SBV b)] -> SArray a b Source # readArray :: SArray a b -> SBV a -> SBV b Source # writeArray :: SymVal b => SArray a b -> SBV a -> SBV b -> SArray a b Source # mergeArrays :: SymVal b => SBV Bool -> SArray a b -> SArray a b -> SArray a b Source # newArrayInState :: (HasKind a, HasKind b) => Maybe String -> Maybe (SBV b) -> State -> IO (SArray a b) Source # |
newArray_ :: (SymArray array, HasKind a, HasKind b) => Maybe (SBV b) -> Symbolic (array a b) Source #
Create a new anonymous array, possibly with a default initial value.
NB. For a version which generalizes over the underlying monad, see newArray_
newArray :: (SymArray array, HasKind a, HasKind b) => String -> Maybe (SBV b) -> Symbolic (array a b) Source #
Create a named new array, possibly with a default initial value.
NB. For a version which generalizes over the underlying monad, see newArray
Arrays implemented in terms of SMT-arrays: http://smtlib.cs.uiowa.edu/theories-ArraysEx.shtml
- Maps directly to SMT-lib arrays
- Reading from an uninitialized value is OK. If the default value is given in
newArray
, it will be the result. Otherwise, the read yields an uninterpreted constant. - Can check for equality of these arrays
- Cannot be used in code-generation (i.e., compilation to C)
- Cannot quick-check theorems using
SArray
values
Instances
Creating symbolic values
Single value
These functions simplify declaring symbolic variables of various types. Strictly speaking, they are just synonyms
for free
(specialized at the given type), but they might be easier to use. We provide both the named and anonymous
versions, latter with the underscore suffix.
sRational_ :: Symbolic SRational Source #
Declare an unnamed SRational
.
NB. For a version which generalizes over the underlying monad, see sRational_
sFloatingPoint :: ValidFloat eb sb => String -> Symbolic (SFloatingPoint eb sb) Source #
Declare a named 'SFloatingPoint eb sb'
NB. For a version which generalizes over the underlying monad, see sFloatingPoint
sFloatingPoint_ :: ValidFloat eb sb => Symbolic (SFloatingPoint eb sb) Source #
Declare an unnamed SFloatingPoint
eb
sb
NB. For a version which generalizes over the underlying monad, see sFloatingPoint_
sFPSingle_ :: Symbolic SFPSingle Source #
Declare an unnamed SFPSingle
NB. For a version which generalizes over the underlying monad, see sFPSingle_
sFPDouble_ :: Symbolic SFPDouble Source #
Declare an unnamed SFPDouble
NB. For a version which generalizes over the underlying monad, see sFPDouble_
sTuple :: (SymTuple tup, SymVal tup) => String -> Symbolic (SBV tup) Source #
Declare a named tuple.
NB. For a version which generalizes over the underlying monad, see sTuple
sTuple_ :: (SymTuple tup, SymVal tup) => Symbolic (SBV tup) Source #
Declare an unnamed tuple.
NB. For a version which generalizes over the underlying monad, see sTuple_
List of values
These functions simplify declaring a sequence symbolic variables of various types. Strictly speaking, they are just synonyms
for mapM
free
(specialized at the given type), but they might be easier to use.
sRationals :: [String] -> Symbolic [SRational] Source #
Declare a list of SRational
values.
NB. For a version which generalizes over the underlying monad, see sRationals
sFloatingPoints :: ValidFloat eb sb => [String] -> Symbolic [SFloatingPoint eb sb] Source #
Declare a list of SFloatingPoint
eb
sb
's
NB. For a version which generalizes over the underlying monad, see sFloatingPoints
sFPBFloats :: [String] -> Symbolic [SFPBFloat] Source #
Declare a list of SFPQuad
s
NB. For a version which generalizes over the underlying monad, see sFPBFloats
sFPSingles :: [String] -> Symbolic [SFPSingle] Source #
Declare a list of SFPSingle
s
NB. For a version which generalizes over the underlying monad, see sFPSingles
sFPDoubles :: [String] -> Symbolic [SFPDouble] Source #
Declare a list of SFPDouble
s
NB. For a version which generalizes over the underlying monad, see sFPDoubles
sTuples :: (SymTuple tup, SymVal tup) => [String] -> Symbolic [SBV tup] Source #
Declare a list of tuples.
NB. For a version which generalizes over the underlying monad, see sTuples
Symbolic Equality and Comparisons
Symbolic equality provides the notion of what it means to be equal, similar to Haskell's Eq
class, except allowing comparison of
symbolic values. The methods are .==
and ./=
, returning SBool
results. We also provide a notion of strong equality (.===
and ./==
),
which is useful for floating-point value comparisons as it deals more uniformly with NaN
and positive/negative zeros. Additionally, we
provide distinct
that can be used to assert all elements of a list are different from each other, and distinctExcept
which is similar
to distinct
but allows for certain values to be considered different. These latter two functions are useful in modeling a variety of
puzzles and cardinality constraints:
>>>
prove $ \a -> distinctExcept [a, a] [0::SInteger] .<=> a .== 0
Q.E.D.>>>
prove $ \a b -> distinctExcept [a, b] [0::SWord8] .<=> (a .== b .=> a .== 0)
Q.E.D.>>>
prove $ \a b c d -> distinctExcept [a, b, c, d] [] .== distinct [a, b, c, (d::SInteger)]
Q.E.D.
class EqSymbolic a where Source #
Symbolic Equality. Note that we can't use Haskell's Eq
class since Haskell insists on returning Bool
Comparing symbolic values will necessarily return a symbolic value.
(.==) :: a -> a -> SBool infix 4 Source #
Symbolic equality.
(./=) :: a -> a -> SBool infix 4 Source #
Symbolic inequality.
(.===) :: a -> a -> SBool infix 4 Source #
Strong equality. On floats (SFloat
/SDouble
), strong equality is object equality; that
is NaN == NaN
holds, but +0 == -0
doesn't. On other types, (.===) is simply (.==).
Note that (.==) is the right notion of equality for floats per IEEE754 specs, since by
definition +0 == -0
and NaN
equals no other value including itself. But occasionally
we want to be stronger and state NaN
equals NaN
and +0
and -0
are different from
each other. In a context where your type is concrete, simply use fpIsEqualObject
. But in
a polymorphic context, use the strong equality instead.
NB. If you do not care about or work with floats, simply use (.==) and (./=).
(./==) :: a -> a -> SBool infix 4 Source #
Negation of strong equality. Equaivalent to negation of (.===) on all types.
distinct :: [a] -> SBool Source #
Returns (symbolic) sTrue
if all the elements of the given list are different.
distinctExcept :: [a] -> [a] -> SBool Source #
Returns (symbolic) sTrue
if all the elements of the given list are different. The second
list contains exceptions, i.e., if an element belongs to that set, it will be considered
distinct regardless of repetition.
allEqual :: [a] -> SBool Source #
Returns (symbolic) sTrue
if all the elements of the given list are the same.
sElem :: a -> [a] -> SBool Source #
Symbolic membership test.
sNotElem :: a -> [a] -> SBool Source #
Symbolic negated membership test.
Instances
EqSymbolic Bool Source # | |
Defined in Data.SBV.Core.Model (.==) :: Bool -> Bool -> SBool Source # (./=) :: Bool -> Bool -> SBool Source # (.===) :: Bool -> Bool -> SBool Source # (./==) :: Bool -> Bool -> SBool Source # distinct :: [Bool] -> SBool Source # distinctExcept :: [Bool] -> [Bool] -> SBool Source # allEqual :: [Bool] -> SBool Source # | |
EqSymbolic RegExp Source # | Regular expressions can be compared for equality. Note that we diverge here from the equality in the concrete sense; i.e., the Eq instance does not match the symbolic case. This is a bit unfortunate, but unavoidable with the current design of how we "distinguish" operators. Hopefully shouldn't be a big deal, though one should be careful. |
Defined in Data.SBV.Core.Model (.==) :: RegExp -> RegExp -> SBool Source # (./=) :: RegExp -> RegExp -> SBool Source # (.===) :: RegExp -> RegExp -> SBool Source # (./==) :: RegExp -> RegExp -> SBool Source # distinct :: [RegExp] -> SBool Source # distinctExcept :: [RegExp] -> [RegExp] -> SBool Source # allEqual :: [RegExp] -> SBool Source # | |
EqSymbolic a => EqSymbolic [a] Source # | |
Defined in Data.SBV.Core.Model (.==) :: [a] -> [a] -> SBool Source # (./=) :: [a] -> [a] -> SBool Source # (.===) :: [a] -> [a] -> SBool Source # (./==) :: [a] -> [a] -> SBool Source # distinct :: [[a]] -> SBool Source # distinctExcept :: [[a]] -> [[a]] -> SBool Source # allEqual :: [[a]] -> SBool Source # | |
EqSymbolic a => EqSymbolic (Maybe a) Source # | |
Defined in Data.SBV.Core.Model (.==) :: Maybe a -> Maybe a -> SBool Source # (./=) :: Maybe a -> Maybe a -> SBool Source # (.===) :: Maybe a -> Maybe a -> SBool Source # (./==) :: Maybe a -> Maybe a -> SBool Source # distinct :: [Maybe a] -> SBool Source # distinctExcept :: [Maybe a] -> [Maybe a] -> SBool Source # allEqual :: [Maybe a] -> SBool Source # | |
EqSymbolic (SBV a) Source # | |
Defined in Data.SBV.Core.Model (.==) :: SBV a -> SBV a -> SBool Source # (./=) :: SBV a -> SBV a -> SBool Source # (.===) :: SBV a -> SBV a -> SBool Source # (./==) :: SBV a -> SBV a -> SBool Source # distinct :: [SBV a] -> SBool Source # distinctExcept :: [SBV a] -> [SBV a] -> SBool Source # allEqual :: [SBV a] -> SBool Source # | |
EqSymbolic a => EqSymbolic (S a) Source # | Symbolic equality for |
Defined in Documentation.SBV.Examples.ProofTools.BMC (.==) :: S a -> S a -> SBool Source # (./=) :: S a -> S a -> SBool Source # (.===) :: S a -> S a -> SBool Source # (./==) :: S a -> S a -> SBool Source # distinct :: [S a] -> SBool Source # distinctExcept :: [S a] -> [S a] -> SBool Source # allEqual :: [S a] -> SBool Source # | |
(EqSymbolic a, EqSymbolic b) => EqSymbolic (Either a b) Source # | |
Defined in Data.SBV.Core.Model (.==) :: Either a b -> Either a b -> SBool Source # (./=) :: Either a b -> Either a b -> SBool Source # (.===) :: Either a b -> Either a b -> SBool Source # (./==) :: Either a b -> Either a b -> SBool Source # distinct :: [Either a b] -> SBool Source # distinctExcept :: [Either a b] -> [Either a b] -> SBool Source # allEqual :: [Either a b] -> SBool Source # | |
(EqSymbolic a, EqSymbolic b) => EqSymbolic (a, b) Source # | |
Defined in Data.SBV.Core.Model (.==) :: (a, b) -> (a, b) -> SBool Source # (./=) :: (a, b) -> (a, b) -> SBool Source # (.===) :: (a, b) -> (a, b) -> SBool Source # (./==) :: (a, b) -> (a, b) -> SBool Source # distinct :: [(a, b)] -> SBool Source # distinctExcept :: [(a, b)] -> [(a, b)] -> SBool Source # allEqual :: [(a, b)] -> SBool Source # | |
EqSymbolic (SArray a b) Source # | |
Defined in Data.SBV.Core.Model (.==) :: SArray a b -> SArray a b -> SBool Source # (./=) :: SArray a b -> SArray a b -> SBool Source # (.===) :: SArray a b -> SArray a b -> SBool Source # (./==) :: SArray a b -> SArray a b -> SBool Source # distinct :: [SArray a b] -> SBool Source # distinctExcept :: [SArray a b] -> [SArray a b] -> SBool Source # allEqual :: [SArray a b] -> SBool Source # | |
(EqSymbolic a, EqSymbolic b, EqSymbolic c) => EqSymbolic (a, b, c) Source # | |
Defined in Data.SBV.Core.Model (.==) :: (a, b, c) -> (a, b, c) -> SBool Source # (./=) :: (a, b, c) -> (a, b, c) -> SBool Source # (.===) :: (a, b, c) -> (a, b, c) -> SBool Source # (./==) :: (a, b, c) -> (a, b, c) -> SBool Source # distinct :: [(a, b, c)] -> SBool Source # distinctExcept :: [(a, b, c)] -> [(a, b, c)] -> SBool Source # allEqual :: [(a, b, c)] -> SBool Source # | |
(EqSymbolic a, EqSymbolic b, EqSymbolic c, EqSymbolic d) => EqSymbolic (a, b, c, d) Source # | |
Defined in Data.SBV.Core.Model (.==) :: (a, b, c, d) -> (a, b, c, d) -> SBool Source # (./=) :: (a, b, c, d) -> (a, b, c, d) -> SBool Source # (.===) :: (a, b, c, d) -> (a, b, c, d) -> SBool Source # (./==) :: (a, b, c, d) -> (a, b, c, d) -> SBool Source # distinct :: [(a, b, c, d)] -> SBool Source # distinctExcept :: [(a, b, c, d)] -> [(a, b, c, d)] -> SBool Source # allEqual :: [(a, b, c, d)] -> SBool Source # sElem :: (a, b, c, d) -> [(a, b, c, d)] -> SBool Source # sNotElem :: (a, b, c, d) -> [(a, b, c, d)] -> SBool Source # | |
(EqSymbolic a, EqSymbolic b, EqSymbolic c, EqSymbolic d, EqSymbolic e) => EqSymbolic (a, b, c, d, e) Source # | |
Defined in Data.SBV.Core.Model (.==) :: (a, b, c, d, e) -> (a, b, c, d, e) -> SBool Source # (./=) :: (a, b, c, d, e) -> (a, b, c, d, e) -> SBool Source # (.===) :: (a, b, c, d, e) -> (a, b, c, d, e) -> SBool Source # (./==) :: (a, b, c, d, e) -> (a, b, c, d, e) -> SBool Source # distinct :: [(a, b, c, d, e)] -> SBool Source # distinctExcept :: [(a, b, c, d, e)] -> [(a, b, c, d, e)] -> SBool Source # allEqual :: [(a, b, c, d, e)] -> SBool Source # sElem :: (a, b, c, d, e) -> [(a, b, c, d, e)] -> SBool Source # sNotElem :: (a, b, c, d, e) -> [(a, b, c, d, e)] -> SBool Source # | |
(EqSymbolic a, EqSymbolic b, EqSymbolic c, EqSymbolic d, EqSymbolic e, EqSymbolic f) => EqSymbolic (a, b, c, d, e, f) Source # | |
Defined in Data.SBV.Core.Model (.==) :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> SBool Source # (./=) :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> SBool Source # (.===) :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> SBool Source # (./==) :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> SBool Source # distinct :: [(a, b, c, d, e, f)] -> SBool Source # distinctExcept :: [(a, b, c, d, e, f)] -> [(a, b, c, d, e, f)] -> SBool Source # allEqual :: [(a, b, c, d, e, f)] -> SBool Source # sElem :: (a, b, c, d, e, f) -> [(a, b, c, d, e, f)] -> SBool Source # sNotElem :: (a, b, c, d, e, f) -> [(a, b, c, d, e, f)] -> SBool Source # | |
(EqSymbolic a, EqSymbolic b, EqSymbolic c, EqSymbolic d, EqSymbolic e, EqSymbolic f, EqSymbolic g) => EqSymbolic (a, b, c, d, e, f, g) Source # | |
Defined in Data.SBV.Core.Model (.==) :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> SBool Source # (./=) :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> SBool Source # (.===) :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> SBool Source # (./==) :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> SBool Source # distinct :: [(a, b, c, d, e, f, g)] -> SBool Source # distinctExcept :: [(a, b, c, d, e, f, g)] -> [(a, b, c, d, e, f, g)] -> SBool Source # allEqual :: [(a, b, c, d, e, f, g)] -> SBool Source # sElem :: (a, b, c, d, e, f, g) -> [(a, b, c, d, e, f, g)] -> SBool Source # sNotElem :: (a, b, c, d, e, f, g) -> [(a, b, c, d, e, f, g)] -> SBool Source # |
class (Mergeable a, EqSymbolic a) => OrdSymbolic a where Source #
Symbolic Comparisons. Similar to Eq
, we cannot implement Haskell's Ord
class
since there is no way to return an Ordering
value from a symbolic comparison.
Furthermore, OrdSymbolic
requires Mergeable
to implement if-then-else, for the
benefit of implementing symbolic versions of max
and min
functions.
(.<) :: a -> a -> SBool infix 4 Source #
Symbolic less than.
(.<=) :: a -> a -> SBool infix 4 Source #
Symbolic less than or equal to.
(.>) :: a -> a -> SBool infix 4 Source #
Symbolic greater than.
(.>=) :: a -> a -> SBool infix 4 Source #
Symbolic greater than or equal to.
Symbolic minimum.
Symbolic maximum.
inRange :: a -> (a, a) -> SBool Source #
Is the value within the allowed inclusive range?
Instances
OrdSymbolic a => OrdSymbolic [a] Source # | |
OrdSymbolic a => OrdSymbolic (Maybe a) Source # | |
Defined in Data.SBV.Core.Model | |
(Ord a, SymVal a) => OrdSymbolic (SBV a) Source # | If comparison is over something SMTLib can handle, just translate it. Otherwise desugar. |
Defined in Data.SBV.Core.Model | |
(OrdSymbolic a, OrdSymbolic b) => OrdSymbolic (Either a b) Source # | |
Defined in Data.SBV.Core.Model (.<) :: Either a b -> Either a b -> SBool Source # (.<=) :: Either a b -> Either a b -> SBool Source # (.>) :: Either a b -> Either a b -> SBool Source # (.>=) :: Either a b -> Either a b -> SBool Source # smin :: Either a b -> Either a b -> Either a b Source # smax :: Either a b -> Either a b -> Either a b Source # inRange :: Either a b -> (Either a b, Either a b) -> SBool Source # | |
(OrdSymbolic a, OrdSymbolic b) => OrdSymbolic (a, b) Source # | |
(OrdSymbolic a, OrdSymbolic b, OrdSymbolic c) => OrdSymbolic (a, b, c) Source # | |
Defined in Data.SBV.Core.Model (.<) :: (a, b, c) -> (a, b, c) -> SBool Source # (.<=) :: (a, b, c) -> (a, b, c) -> SBool Source # (.>) :: (a, b, c) -> (a, b, c) -> SBool Source # (.>=) :: (a, b, c) -> (a, b, c) -> SBool Source # smin :: (a, b, c) -> (a, b, c) -> (a, b, c) Source # smax :: (a, b, c) -> (a, b, c) -> (a, b, c) Source # inRange :: (a, b, c) -> ((a, b, c), (a, b, c)) -> SBool Source # | |
(OrdSymbolic a, OrdSymbolic b, OrdSymbolic c, OrdSymbolic d) => OrdSymbolic (a, b, c, d) Source # | |
Defined in Data.SBV.Core.Model (.<) :: (a, b, c, d) -> (a, b, c, d) -> SBool Source # (.<=) :: (a, b, c, d) -> (a, b, c, d) -> SBool Source # (.>) :: (a, b, c, d) -> (a, b, c, d) -> SBool Source # (.>=) :: (a, b, c, d) -> (a, b, c, d) -> SBool Source # smin :: (a, b, c, d) -> (a, b, c, d) -> (a, b, c, d) Source # smax :: (a, b, c, d) -> (a, b, c, d) -> (a, b, c, d) Source # inRange :: (a, b, c, d) -> ((a, b, c, d), (a, b, c, d)) -> SBool Source # | |
(OrdSymbolic a, OrdSymbolic b, OrdSymbolic c, OrdSymbolic d, OrdSymbolic e) => OrdSymbolic (a, b, c, d, e) Source # | |
Defined in Data.SBV.Core.Model (.<) :: (a, b, c, d, e) -> (a, b, c, d, e) -> SBool Source # (.<=) :: (a, b, c, d, e) -> (a, b, c, d, e) -> SBool Source # (.>) :: (a, b, c, d, e) -> (a, b, c, d, e) -> SBool Source # (.>=) :: (a, b, c, d, e) -> (a, b, c, d, e) -> SBool Source # smin :: (a, b, c, d, e) -> (a, b, c, d, e) -> (a, b, c, d, e) Source # smax :: (a, b, c, d, e) -> (a, b, c, d, e) -> (a, b, c, d, e) Source # inRange :: (a, b, c, d, e) -> ((a, b, c, d, e), (a, b, c, d, e)) -> SBool Source # | |
(OrdSymbolic a, OrdSymbolic b, OrdSymbolic c, OrdSymbolic d, OrdSymbolic e, OrdSymbolic f) => OrdSymbolic (a, b, c, d, e, f) Source # | |
Defined in Data.SBV.Core.Model (.<) :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> SBool Source # (.<=) :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> SBool Source # (.>) :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> SBool Source # (.>=) :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> SBool Source # smin :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> (a, b, c, d, e, f) Source # smax :: (a, b, c, d, e, f) -> (a, b, c, d, e, f) -> (a, b, c, d, e, f) Source # inRange :: (a, b, c, d, e, f) -> ((a, b, c, d, e, f), (a, b, c, d, e, f)) -> SBool Source # | |
(OrdSymbolic a, OrdSymbolic b, OrdSymbolic c, OrdSymbolic d, OrdSymbolic e, OrdSymbolic f, OrdSymbolic g) => OrdSymbolic (a, b, c, d, e, f, g) Source # | |
Defined in Data.SBV.Core.Model (.<) :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> SBool Source # (.<=) :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> SBool Source # (.>) :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> SBool Source # (.>=) :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> SBool Source # smin :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) Source # smax :: (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) -> (a, b, c, d, e, f, g) Source # inRange :: (a, b, c, d, e, f, g) -> ((a, b, c, d, e, f, g), (a, b, c, d, e, f, g)) -> SBool Source # |
class Equality a where Source #
Equality as a proof method. Allows for very concise construction of equivalence proofs, which is very typical in bit-precise proofs.
Instances
Conditionals: Mergeable values
class Mergeable a where Source #
Symbolic conditionals are modeled by the Mergeable
class, describing
how to merge the results of an if-then-else call with a symbolic test. SBV
provides all basic types as instances of this class, so users only need
to declare instances for custom data-types of their programs as needed.
A Mergeable
instance may be automatically derived for a custom data-type
with a single constructor where the type of each field is an instance of
Mergeable
, such as a record of symbolic values. Users only need to add
Generic
and Mergeable
to the deriving
clause for the data-type. See
Status
for an example and an
illustration of what the instance would look like if written by hand.
The function select
is a total-indexing function out of a list of choices
with a default value, simulating array/list indexing. It's an n-way generalization
of the ite
function.
Minimal complete definition: None, if the type is instance of Generic
. Otherwise
symbolicMerge
. Note that most types subject to merging are likely to be
trivial instances of Generic
.
Nothing
symbolicMerge :: Bool -> SBool -> a -> a -> a Source #
Merge two values based on the condition. The first argument states whether we force the then-and-else branches before the merging, at the word level. This is an efficiency concern; one that we'd rather not make but unfortunately necessary for getting symbolic simulation working efficiently.
select :: (Ord b, SymVal b, Num b) => [a] -> a -> SBV b -> a Source #
Total indexing operation. select xs default index
is intuitively
the same as xs !! index
, except it evaluates to default
if index
underflows/overflows.
Instances
ite :: Mergeable a => SBool -> a -> a -> a Source #
If-then-else. This is by definition symbolicMerge
with both
branches forced. This is typically the desired behavior, but also
see iteLazy
should you need more laziness.
iteLazy :: Mergeable a => SBool -> a -> a -> a Source #
A Lazy version of ite, which does not force its arguments. This might cause issues for symbolic simulation with large thunks around, so use with care.
Symbolic integral numbers
class (SymVal a, Num a, Bits a, Integral a) => SIntegral a Source #
Symbolic Numbers. This is a simple class that simply incorporates all number like
base types together, simplifying writing polymorphic type-signatures that work for all
symbolic numbers, such as SWord8
, SInt8
etc. For instance, we can write a generic
list-minimum function as follows:
mm :: SIntegral a => [SBV a] -> SBV a mm = foldr1 (a b -> ite (a .<= b) a b)
It is similar to the standard Integral
class, except ranging over symbolic instances.
Instances
SIntegral Int8 Source # | |
Defined in Data.SBV.Core.Model | |
SIntegral Int16 Source # | |
Defined in Data.SBV.Core.Model | |
SIntegral Int32 Source # | |
Defined in Data.SBV.Core.Model | |
SIntegral Int64 Source # | |
Defined in Data.SBV.Core.Model | |
SIntegral Integer Source # | |
Defined in Data.SBV.Core.Model | |
SIntegral Word8 Source # | |
Defined in Data.SBV.Core.Model | |
SIntegral Word16 Source # | |
Defined in Data.SBV.Core.Model | |
SIntegral Word32 Source # | |
Defined in Data.SBV.Core.Model | |
SIntegral Word64 Source # | |
Defined in Data.SBV.Core.Model | |
(KnownNat n, BVIsNonZero n) => SIntegral (IntN n) Source # | |
Defined in Data.SBV.Core.Sized | |
(KnownNat n, BVIsNonZero n) => SIntegral (WordN n) Source # | |
Defined in Data.SBV.Core.Sized |
Division and Modulus
class SDivisible a where Source #
The SDivisible
class captures the essence of division.
Unfortunately we cannot use Haskell's Integral
class since the Real
and Enum
superclasses are not implementable for symbolic bit-vectors.
However, quotRem
and divMod
both make perfect sense, and the SDivisible
class captures
this operation. One issue is how division by 0 behaves. The verification
technology requires total functions, and there are several design choices
here. We follow Isabelle/HOL approach of assigning the value 0 for division
by 0. Therefore, we impose the following pair of laws:
xsQuotRem
0 = (0, x) xsDivMod
0 = (0, x)
Note that our instances implement this law even when x
is 0
itself.
NB. quot
truncates toward zero, while div
truncates toward negative infinity.
C code generation of division operations
In the case of division or modulo of a minimal signed value (e.g. -128
for
SInt8
) by -1
, SMTLIB and Haskell agree on what the result should be.
Unfortunately the result in C code depends on CPU architecture and compiler
settings, as this is undefined behaviour in C. **SBV does not guarantee**
what will happen in generated C code in this corner case.
Instances
Bit-vector operations
Conversions
sFromIntegral :: forall a b. (Integral a, HasKind a, Num a, SymVal a, HasKind b, Num b, SymVal b) => SBV a -> SBV b Source #
Conversion between integral-symbolic values, akin to Haskell's fromIntegral
Shifts and rotates
Symbolic words (both signed and unsigned) are an instance of Haskell's Bits
class, so regular
bitwise operations are automatically available for them. Shifts and rotates, however, require
specialized type-signatures since Haskell insists on an Int
second argument for them.
sShiftRight :: (SIntegral a, SIntegral b) => SBV a -> SBV b -> SBV a Source #
Generalization of shiftR
, when the shift-amount is symbolic. Since Haskell's
shiftR
only takes an Int
as the shift amount, it cannot be used when we have
a symbolic amount to shift with.
NB. If the shiftee is signed, then this is an arithmetic shift; otherwise it's logical,
following the usual Haskell convention. See sSignedShiftArithRight
for a variant
that explicitly uses the msb as the sign bit, even for unsigned underlying types.
sBarrelRotateLeft :: (SFiniteBits a, SFiniteBits b) => SBV a -> SBV b -> SBV a Source #
An implementation of rotate-left, using a barrel shifter like design. Only works when both
arguments are finite bitvectors, and furthermore when the second argument is unsigned.
The first condition is enforced by the type, but the second is dynamically checked.
We provide this implementation as an alternative to sRotateLeft
since SMTLib logic
does not support variable argument rotates (as opposed to shifts), and thus this
implementation can produce better code for verification compared to sRotateLeft
.
>>>
prove $ \x y -> (x `sBarrelRotateLeft` y) `sBarrelRotateRight` (y :: SWord32) .== (x :: SWord64)
Q.E.D.
sBarrelRotateRight :: (SFiniteBits a, SFiniteBits b) => SBV a -> SBV b -> SBV a Source #
An implementation of rotate-right, using a barrel shifter like design. See comments
for sBarrelRotateLeft
for details.
>>>
prove $ \x y -> (x `sBarrelRotateRight` y) `sBarrelRotateLeft` (y :: SWord32) .== (x :: SWord64)
Q.E.D.
sSignedShiftArithRight :: (SFiniteBits a, SIntegral b) => SBV a -> SBV b -> SBV a Source #
Arithmetic shift-right with a symbolic unsigned shift amount. This is equivalent
to sShiftRight
when the argument is signed. However, if the argument is unsigned,
then it explicitly treats its msb as a sign-bit, and uses it as the bit that
gets shifted in. Useful when using the underlying unsigned bit representation to implement
custom signed operations. Note that there is no direct Haskell analogue of this function.
Finite bit-vector operations
class (Ord a, SymVal a, Num a, Bits a) => SFiniteBits a where Source #
Finite bit-length symbolic values. Essentially the same as SIntegral
, but further leaves out Integer
. Loosely
based on Haskell's FiniteBits
class, but with more methods defined and structured differently to fit into the
symbolic world view. Minimal complete definition: sFiniteBitSize
.
sFiniteBitSize :: SBV a -> Int Source #
Bit size.
lsb :: SBV a -> SBool Source #
Least significant bit of a word, always stored at index 0.
msb :: SBV a -> SBool Source #
Most significant bit of a word, always stored at the last position.
blastBE :: SBV a -> [SBool] Source #
Big-endian blasting of a word into its bits.
blastLE :: SBV a -> [SBool] Source #
Little-endian blasting of a word into its bits.
fromBitsBE :: [SBool] -> SBV a Source #
Reconstruct from given bits, given in little-endian.
fromBitsLE :: [SBool] -> SBV a Source #
Reconstruct from given bits, given in little-endian.
sTestBit :: SBV a -> Int -> SBool Source #
sExtractBits :: SBV a -> [Int] -> [SBool] Source #
Variant of sTestBit
, where we want to extract multiple bit positions.
sPopCount :: SBV a -> SWord8 Source #
Variant of popCount
, returning a symbolic value.
setBitTo :: SBV a -> Int -> SBool -> SBV a Source #
fullAdder :: SBV a -> SBV a -> (SBool, SBV a) Source #
Full adder, returns carry-out from the addition. Only for unsigned quantities.
fullMultiplier :: SBV a -> SBV a -> (SBV a, SBV a) Source #
Full multiplier, returns both high and low-order bits. Only for unsigned quantities.
sCountLeadingZeros :: SBV a -> SWord8 Source #
Count leading zeros in a word, big-endian interpretation.
sCountTrailingZeros :: SBV a -> SWord8 Source #
Count trailing zeros in a word, big-endian interpretation.