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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 +. + diff --git a/Setup.hs b/Setup.hs new file mode 100644 --- /dev/null +++ b/Setup.hs @@ -0,0 +1,2 @@ +import Distribution.Simple +main = defaultMain diff --git a/array-forth.cabal b/array-forth.cabal new file mode 100644 --- /dev/null +++ b/array-forth.cabal @@ -0,0 +1,82 @@ +-- Initial arrayForth.cabal generated by cabal init. For further +-- documentation, see http://haskell.org/cabal/users-guide/ + +-- The name of the package. +name: array-forth + +-- The package version. See the Haskell package versioning policy (PVP) +-- for standards guiding when and how versions should be incremented. +-- http://www.haskell.org/haskellwiki/Package_versioning_policy +-- PVP summary: +-+------- breaking API changes +-- | | +----- non-breaking API additions +-- | | | +--- code changes with no API change +version: 0.2.0.2 + +-- A short (one-line) description of the package. +synopsis: A simple interpreter for arrayForth, the language used on GreenArrays chips. + +description: This is a package for working with arrayForth. This is a variant of Forth used by GreenArrays chips. This package contains an arrayForth simulator, two different representations of arrayForth programs and some utilities like parsing. + + It also supports synthesizing arrayForth programs using MCMC. The basic idea is to find arrayForth programs by taking a simple prior distribution of programs and using a randomized hill-climbing algorithm to find a program fulfilling certain tests. + +-- A longer description of the package. +-- description: + +-- The license under which the package is released. +license: GPL-3 + +-- The file containing the license text. +license-file: LICENSE + +-- The package author(s). +author: Tikhon Jelvis + +-- An email address to which users can send suggestions, bug reports, and +-- patches. +maintainer: tikhon@jelv.is + +-- A copyright notice. +-- copyright: + +category: Language + +build-type: Simple + +-- Constraint on the version of Cabal needed to build this package. +cabal-version: >=1.8 + +source-repository head + type: git + location: git://github.com/TikhonJelvis/array-forth.git + +library + -- Modules exported by the library. + exposed-modules: Language.ArrayForth.Distance, + Language.ArrayForth.Interpreter, + Language.ArrayForth.NativeProgram, + Language.ArrayForth.Opcode, + Language.ArrayForth.Parse, + Language.ArrayForth.Program, + Language.ArrayForth.Stack, + Language.ArrayForth.State, + Language.ArrayForth.Synthesis + + hs-source-dirs: src + -- Modules included in this library but not exported. + -- other-modules: + + -- Other library packages from which modules are imported. + build-depends: base ==4.5.*, mcmc-synthesis >=0.1, MonadRandom ==0.1.*, + OddWord >=1.0.0, split ==0.1.*, vector ==0.9.* + GHC-options: -Wall -funbox-strict-fields -fno-warn-orphans -rtsopts + +executable mcmc-demo + Main-is: src/Main.hs + build-depends: base ==4.5.*, mcmc-synthesis >=0.1, array-forth, + MonadRandom ==0.1.* + GHC-options: -Wall -rtsopts + +executable array-forth + Main-is: src/Run.hs + build-depends: base ==4.5.*, vector ==0.9.*, split ==0.1.*, array-forth + GHC-options: -Wall -rtsopts diff --git a/src/Language/ArrayForth/Distance.hs b/src/Language/ArrayForth/Distance.hs new file mode 100644 --- /dev/null +++ b/src/Language/ArrayForth/Distance.hs @@ -0,0 +1,32 @@ +module Language.ArrayForth.Distance where + +import Data.Bits (Bits, popCount, xor) + +import Language.ArrayForth.Opcode (F18Word) +import Language.ArrayForth.State + +-- | A function that computes a measure of "distance" between two +-- states. The larger the returned number, the more different the +-- states. +type Distance = State -> State -> Double + +-- | Counts the number of bits that differ between two numbers. +countBits :: (Integral n, Bits n) => n -> n -> Int +countBits n₁ n₂ = popCount $ (fromIntegral n₁ :: Int) `xor` fromIntegral n₂ + +-- | Return a distance function that counts the different bits between +-- the given registers. You could use it like `compareRegisters [s, t]`. +registers :: [State -> F18Word] -> Distance +registers regs s₁ s₂ = fromIntegral . sum $ zipWith countBits (go s₁) (go s₂) + where go state = map ($ state) regs + +-- | Returns a distance function that counts the different bits +-- between the given memory locations. +locations :: [F18Word] -> Distance +locations addresses s₁ s₂ = fromIntegral . sum $ zipWith countBits (go s₁) (go s₂) + where go state = map (memory state !) addresses + +-- | Combines multiple distance functions to create a new one, by +-- summing the different distances. +distances :: [Distance] -> Distance +distances dists s₁ s₂ = sum [dist s₁ s₂ | dist <- dists] diff --git a/src/Language/ArrayForth/Interpreter.hs b/src/Language/ArrayForth/Interpreter.hs new file mode 100644 --- /dev/null +++ b/src/Language/ArrayForth/Interpreter.hs @@ -0,0 +1,117 @@ +{-# LANGUAGE NamedFieldPuns #-} +module Language.ArrayForth.Interpreter where + +import Data.Bits (bit, bitSize, complement, + shift, testBit, xor, (.&.), + (.|.)) + +import Language.ArrayForth.NativeProgram +import Language.ArrayForth.Opcode +import Language.ArrayForth.State + +-- | Runs a single word's worth of instructions starting from the given state. +word :: Instrs -> State -> State +word (Instrs a b c d) state = let s₁ = execute a state + s₂ = if endWord a then s₁ else execute b s₁ + s₃ = if endWord a || endWord b + then s₂ else execute c s₂ in + if endWord a || endWord b || endWord c then s₃ else execute d s₃ +word (Jump3 a b c addr) state = let s₁ = execute a state + s₂ = if endWord a then s₁ else execute b s₁ in + if endWord a || endWord b then s₂ else jump c addr s₂ +word (Jump2 a b addr) state = let s' = execute a state in + if endWord a then s' else jump b addr s' +word (Jump1 a addr) state = jump a addr state +word (Constant _) _ = error "Cannot execute a constant!" + +-- | Executes a single instruction in the given state, incrementing +-- the program counter. +step :: State -> State +step state@State {p} = word (next state) $ state {p = p + 1, i = toBits $ next state} + +-- | Returns a trace of the program's execution. The trace is a list +-- of the state of the chip after each step. +traceProgram :: State -> [State] +traceProgram = iterate step + +-- | Trace a program until it either hits four nops or all 0s. +stepProgram :: State -> [State] +stepProgram = takeWhile (not . done) . traceProgram + where done state = i state == 0x39ce7 || i state == 0 + +-- | Runs the program unil it hits a terminal state, returning only +-- the resulting state. +eval :: State -> State +eval state = last $ state : stepProgram state + +-- | Executes the specified program on the given state until it hits a +-- "terminal" word--a word made up of four nops or all 0s. +runNativeProgram :: State -> NativeProgram -> State +runNativeProgram start program = eval $ setProgram 0 program start + +-- | Estimates the execution time of a program trace. +countTime :: [State] -> Double +countTime = runningTime . map (fromBits . i) + +-- | Checks that the program trace terminated in at most n steps, +-- returning Nothing otherwise. +throttle :: Int -> [State] -> Either [State] [State] +throttle n state | null res = Right [startState] + | length res == n = Left res + | otherwise = Right res + where res = take n state + +-- | Does the given opcode cause the current word to stop executing? +endWord :: Opcode -> Bool +endWord = (`elem` [Ret, Exec, Jmp, Call, Unext, Next, If, MinusIf]) + +-- | Executes an opcode on the given state. +execute :: Opcode -> State -> State +execute op state@State {a, b, p, r, s, t, memory} = case op of + Ret -> fst . rpop $ state {p = r} + Exec -> state {r = p, p = r} + Unext -> if r == 0 then fst $ rpop state else state {r = r - 1, p = p - 1} + FetchP -> dpush (state {p = p + 1}) $ memory ! p + FetchPlus -> dpush (state {a = a + 1}) $ memory ! a + FetchB -> dpush state $ memory ! b + Fetch -> dpush state $ memory ! a + StoreP -> state' {p = p + 1, memory = set memory p top} + StorePlus -> state' {a = a + 1, memory = set memory a top} + StoreB -> state' {memory = set memory b top} + Store -> state' {memory = set memory a top} + MultiplyStep -> multiplyStep + Times2 -> state {t = t `shift` 1} + Div2 -> state {t = t `shift` (-1)} + Not -> state {t = complement t} + Plus -> state' {t = s + t} + And -> state' {t = s .&. t} + Or -> state' {t = s `xor` t} + Drop -> fst $ dpop state + Dup -> dpush state t + Pop -> let (s', res) = rpop state in dpush s' res + Over -> dpush state s + ReadA -> dpush state a + Nop -> state + Push -> rpush state' top + SetB -> state' {b = top} + SetA -> state' {a = top} + _ -> error "Cannot jump without an address!" + where (state', top) = dpop state + multiplyStep + | even a = let t0 = (t .&. 1) `shift` (bitSize t - 1) in + state { a = t0 .|. a `shift` (-1) + , t = t .&. bit 17 .|. t `shift` (-1)} + | otherwise = let sum0 = (s + t) `shift` (bitSize t - 1) + sum17 = (s + t) .&. bit 17 in + state { a = sum0 .|. a `shift` (-1) + , t = sum17 .|. (s + t) `shift` (-1) } + +-- | Execute a jump instruction to the given address. +jump :: Opcode -> F18Word -> State -> State +jump op addr state@State{p, r, t} = case op of + Jmp -> state {p = addr} + Call -> (rpush state p) {p = addr} + Next -> if r == 0 then fst $ rpop state else state {r = r - 1, p = addr} + If -> if t /= 0 then state {p = addr} else state + MinusIf -> if t `testBit` pred (bitSize (0 :: F18Word)) then state else state {p = addr} + _ -> error "Non-jump instruction given a jump address!" diff --git a/src/Language/ArrayForth/NativeProgram.hs b/src/Language/ArrayForth/NativeProgram.hs new file mode 100644 --- /dev/null +++ b/src/Language/ArrayForth/NativeProgram.hs @@ -0,0 +1,103 @@ +{-# LANGUAGE FlexibleInstances #-} +{-# LANGUAGE OverlappingInstances #-} +{-# LANGUAGE TypeSynonymInstances #-} +module Language.ArrayForth.NativeProgram where + +import Control.Applicative ((<$>), (<*>)) +import Control.Monad ((<=<)) + +import Data.Bits (shift, (.&.), (.|.)) +import Data.List.Split (chunk, keepDelimsR, split, whenElt) +import Data.String (IsString, fromString) + +import Language.ArrayForth.Opcode +import Language.ArrayForth.Parse + +-- | Represents a word in memory. This word can either contain +-- opcodes, opcodes and a jump address or just a constant number. +data Instrs = Instrs Opcode Opcode Opcode Opcode + | Jump3 Opcode Opcode Opcode F18Word + | Jump2 Opcode Opcode F18Word + | Jump1 Opcode F18Word + | Constant F18Word deriving (Eq) + +instance Show Instrs where + show (Instrs a b c d) = unwords $ map show [a, b, c, d] + show (Jump3 a b c addr) = unwords (map show [a, b, c]) ++ " " ++ show addr + show (Jump2 a b addr) = unwords (map show [a, b]) ++ " " ++ show addr + show (Jump1 a addr) = show a ++ " " ++ show addr + show (Constant n) = show n + showList = (++) . unwords . map show + +-- | A program in the F18A instruction set. +type NativeProgram = [Instrs] + +-- | Splits a list into chunks of at most four, breaking off a chunk +-- whenever it sees an element matching the given predicate. This is +-- useful for splitting a program along word boundaries, accounting +-- for jump addresses. +splitWords :: (a -> Bool) -> [a] -> [[a]] +splitWords isNum = chunk 4 <=< split (keepDelimsR $ whenElt isNum) + +-- | Read a whole program, splitting instructions up into words. +readNativeProgram :: String -> Either ParseError NativeProgram +readNativeProgram = mapM go . splitWords isNumber . words + where go [a, b, c, d] = do c' <- readOpcode c + if not $ isJump c' + then Instrs <$> op a <*> op b <*> op c <*> op3 d + else Jump3 <$> op a <*> op b <*> jump c <*> readWord d + go [a, b, c] = Jump2 <$> op a <*> jump b <*> readWord c + go [a, b] = Jump1 <$> jump a <*> readWord b + go [a] = Constant <$> readWord a + go _ = error "Wrong number of instruction tokens!" + wrap cond err str = do code <- readOpcode str + if cond code then Right code else Left $ err code + op = wrap (not . isJump) $ NoAddr . show + op3 = wrap slot3 $ NotSlot3 . show + jump = wrap isJump $ NotJump . show + +instance Read NativeProgram where + readsPrec _ str = [(result, "")] + where result = case readNativeProgram str of + Right res -> res + Left err -> error $ show err + +instance IsString NativeProgram where fromString = read + +-- | Returns the given instructions as an actual word. This assumes +-- the address is sized appropriately. +toBits :: Instrs -> F18Word +toBits (Instrs a b c d) = fromOpcode a `shift` 13 .|. fromOpcode b `shift` 8 .|. + fromOpcode c `shift` 3 .|. fromOpcode d `shift` (-2) +toBits (Jump3 a b c addr) = fromOpcode a `shift` 13 .|. fromOpcode b `shift` 8 .|. + fromOpcode c `shift` 3 .|. addr +toBits (Jump2 a b addr) = fromOpcode a `shift` 13 .|. fromOpcode b `shift` 8 .|. addr +toBits (Jump1 a addr) = fromOpcode a `shift` 13 .|. addr +toBits (Constant n) = n + +-- | Reads in a word as a set of opcodes. +fromBits :: F18Word -> Instrs +fromBits n | isJump a = Jump1 a $ n .&. 0x3FF + | isJump b = Jump2 a b $ n .&. 0xFF + | isJump c = Jump3 a b c $ n .&. 0x7 + | otherwise = Instrs a b c d + where a = toOpcode $ n `shift` (-13) + b = toOpcode $ n `shift` (-8) .&. 0x1F + c = toOpcode $ n `shift` (-3) .&. 0x1F + d = toOpcode $ (n .&. 0x7) `shift` 2 + +-- | Returns the opcodes in the given instruction word. A constant +-- corresponds to not having any opcodes. +toOpcodes :: Instrs -> [Opcode] +toOpcodes (Instrs a b c d) = [a, b, c, d] +toOpcodes (Jump3 a b c _) = [a, b, c] +toOpcodes (Jump2 a b _) = [a, b] +toOpcodes (Jump1 a _) = [a] +toOpcodes Constant{} = [] + +-- | Estimates the running time of the program in nanoseconds. This is +-- based on the numbers provided in the manual: faster instructions +-- take 1.5 nanoseconds and slower ones take 5. For now, this estimate +-- ignores control flow like ifs and loops. +runningTime :: NativeProgram -> Double +runningTime = sum . map opcodeTime . reverse . dropWhile (== Nop) . reverse . concatMap toOpcodes diff --git a/src/Language/ArrayForth/Opcode.hs b/src/Language/ArrayForth/Opcode.hs new file mode 100644 --- /dev/null +++ b/src/Language/ArrayForth/Opcode.hs @@ -0,0 +1,91 @@ +module Language.ArrayForth.Opcode where + +import Data.List (elemIndex) +import Data.Word.Odd (Word18) + +import Language.ArrayForth.Parse (ParseError (..)) + +-- | The 18-bit word type used by Greenarrays chips. +type F18Word = Word18 + +-- | Each F18A instruction, ordered by opcode. +data Opcode = Ret -- ; + | Exec -- ex + | Jmp -- name ; + | Call -- name + | Unext -- unext + | Next -- next + | If -- if + | MinusIf -- -if + | FetchP -- @p + | FetchPlus -- @+ + | FetchB -- @b + | Fetch -- @ + | StoreP -- !p + | StorePlus -- !+ + | StoreB -- !b + | Store -- ! + | MultiplyStep -- +* + | Times2 -- 2* + | Div2 -- 2/ + | Not -- - + | Plus -- + + | And -- and + | Or -- or + | Drop -- drop + | Dup -- dup + | Pop -- pop + | Over -- over + | ReadA -- a + | Nop -- . + | Push -- push + | SetB -- b! + | SetA -- a! + deriving (Eq, Bounded, Enum) + +-- | The names of the different instructions, ordered by opcode. +names :: [String] +names = [";", "ex", "jump", "call", "unext", "next", "if", "-if", "@p", "@+", "@b", "@", + "!p", "!+", "!b", "!", "+*", "2*", "2/", "-", "+", "and", "or", "drop", "dup", + "pop", "over", "a", ".", "push", "b!", "a!"] + +-- | All of the opcodes, in order. +opcodes :: [Opcode] +opcodes = [minBound..maxBound] + +instance Show Opcode where show op = names !! fromEnum op + +-- | Tries to read a given string as an opcode from the list of names. +readOpcode :: String -> Either ParseError Opcode +readOpcode token = case elemIndex token names of + Just res -> Right $ toEnum res + Nothing -> Left $ BadOpcode token + +instance Read Opcode where readsPrec _ str = case readOpcode str of + Left err -> error $ show err + Right r -> [(r, "")] + +-- | Converts a word to an opcode. The word has to be < 32. +toOpcode :: F18Word -> Opcode +toOpcode = toEnum . fromIntegral + +-- | Converts an Opcode to its 18-bit word representation. +fromOpcode :: Opcode -> F18Word +fromOpcode = fromIntegral . fromEnum + +-- | Returns whether the given opcode is a jump instruction expecting +-- an address. +isJump :: Opcode -> Bool +isJump = (`elem` [Jmp, Call, Next, If, MinusIf]) + +-- | Can the given opcode go in the last slot? +slot3 :: Opcode -> Bool +slot3 = (`elem` [Ret, MultiplyStep, Unext, Plus, FetchP, Dup, StoreP, Nop]) + +-- | Estimates how long a given opcode will take to execute. Normal +-- opcodes take 1.5 nanoseconds where ones that access the memory take +-- 5 nanoseconds. +opcodeTime :: Opcode -> Double +opcodeTime op = if memoryOp op then 5 else 1.5 + where memoryOp = (`elem` [FetchP, FetchPlus, FetchB, Fetch, StoreP, + StorePlus, StoreB, Store]) diff --git a/src/Language/ArrayForth/Parse.hs b/src/Language/ArrayForth/Parse.hs new file mode 100644 --- /dev/null +++ b/src/Language/ArrayForth/Parse.hs @@ -0,0 +1,29 @@ +module Language.ArrayForth.Parse (ParseError (..), isNumber, readWord) where + +import Text.Printf (printf) + +-- | Possible ways the input string can be malformed. +data ParseError = BadOpcode String + | NotSlot3 String + | NotJump String + | NoAddr String + | BadNumber String + +instance Show ParseError where + show (BadOpcode op) = printf "Invalid opcode `%s'." op + show (NotSlot3 op) = printf "`%s' cannot go into the last slot." op + show (NotJump op) = + printf "`%s' is not a jump instruction and cannot get an address." op + show (NoAddr op) = printf "Missing a jump address for `%s'" op + show (BadNumber n) = printf "`%s' is not a valid number." n + +-- | Is the given string a valid number with no other tokens? +isNumber :: String -> Bool +isNumber str = let asNumber = reads str :: [(Integer, String)] in + not (null asNumber) && (null . snd $ head asNumber) + +-- | Tries to read a word, giving an error if it fails. +readWord :: Read a => String -> Either ParseError a +readWord str = case reads str of + (x, _) : _ -> Right x + [] -> Left $ BadNumber str diff --git a/src/Language/ArrayForth/Program.hs b/src/Language/ArrayForth/Program.hs new file mode 100644 --- /dev/null +++ b/src/Language/ArrayForth/Program.hs @@ -0,0 +1,137 @@ +{-# LANGUAGE FlexibleInstances #-} +{-# LANGUAGE OverlappingInstances #-} +{-# LANGUAGE TypeSynonymInstances #-} +module Language.ArrayForth.Program where + +import Control.Monad ((<=<)) + +import Data.Functor ((<$>)) +import Data.List (find, (\\)) +import Data.String (IsString, fromString) + +import Language.ArrayForth.Interpreter +import Language.ArrayForth.NativeProgram +import Language.ArrayForth.Opcode +import qualified Language.ArrayForth.Parse as P +import Language.ArrayForth.State (State, setProgram) + +data Addr = Concrete F18Word | Abstract String deriving Eq + +instance Show Addr where + show (Concrete n) = show n + show (Abstract s) = ':' : s + +-- | Represents a single instruction as viewed by the +-- synthesizer. This can be an opcode, a numeric literal or a token +-- representing an unused slot. +data Instruction = Opcode Opcode + | Jump Opcode Addr + | Number F18Word + | Label String + | Unused deriving Eq + +-- | A program to be manipulated by the MCMC synthesizer +type Program = [Instruction] + +instance Show Instruction where + show (Opcode op) = show op + show (Jump op addr) = show op ++ " " ++ show addr + show (Number n) = show n + show (Label s) = ':' : s + show Unused = "_" + showList = (++) . unwords . map show + +-- | Tries to parse the given string as an instruction, which can +-- either be a number, an opcode or "_" representing Unused. +readInstruction :: String -> Either P.ParseError Instruction +readInstruction "_" = Right Unused +readInstruction (':':label) = Right $ Label label +readInstruction str | P.isNumber str = Number <$> P.readWord str + | otherwise = Opcode <$> readOpcode str + +-- | Reads a program in the synthesizer's format. +readProgram :: String -> Either P.ParseError Program +readProgram = fixJumps <=< mapM readInstruction . words + where fixJumps [] = Right [] + fixJumps (Opcode op : rest) | isJump op = case rest of + Number n : program -> (Jump op (Concrete n) :) <$> fixJumps program + Label s : program -> (Jump op (Abstract s) :) <$> fixJumps program + _ -> Left . P.NoAddr $ show op + fixJumps (good : rest) = (good :) <$> fixJumps rest + +instance Read Program where + readsPrec _ str = [(result, "")] + where result = case readProgram str of + Right res -> res + Left err -> error $ show err + +instance IsString Program where fromString = read + +-- | Takes a program as handled by the synthesizer and makes it native +-- by turning literal numbers into @p and fixing any issues with +-- instructions going into the last slot as well as prepending +-- nops before + instructions. +toNative :: Program -> NativeProgram +toNative = (>>= toInstrs) . splitWords bound . fixSlot3 . (>>= nopsPlus) . labels . filter (/= Unused) + where labels program = map convert $ filter (not . label) program + where label Label{} = True + label _ = False + values = go 0 program + go _ [] = [] + go n (Label name : rest) = (name, n) : go n rest + go n (_ : rest) = go (n + 1) rest + convert (Jump op (Abstract l)) = maybe (error $ "Unknown label " ++ l) + (Jump op . Concrete) $ lookup l values + convert x = x + nop = Opcode Nop + bound Jump{} = True + bound _ = False + nopsPlus (Opcode Plus) = [nop, Opcode Plus] + nopsPlus x = [x] + fixSlot3 program + | length program < 4 = program + | validOp4 = take 4 program ++ fixSlot3 (drop 4 program) + | otherwise = take 3 program ++ [nop] ++ fixSlot3 (drop 3 program) + where validOp4 = case program !! 3 of Opcode op -> slot3 op + Number{} -> True + _ -> False + toInstrs ls = let (ops, numbers) = addFetchP ls in + convert ops : map (\ (Number n) -> Constant n) numbers + addFetchP [] = ([], []) + addFetchP (n@Number{} : rest) = + let (instrs, consts) = addFetchP rest in (Opcode FetchP : instrs, n : consts) + addFetchP (instr : rest) = + let (instrs, consts) = addFetchP rest in (instr : instrs, consts) + convert [Opcode a, Opcode b, Opcode c, Opcode d] = Instrs a b c d + convert [Opcode a, Opcode b, Jump c addr] = Jump3 a b c $ concrete addr + convert [Opcode a, Jump b addr] = Jump2 a b $ concrete addr + convert [Jump a addr] = Jump1 a $ concrete addr + convert instrs = convert . take 4 $ instrs ++ repeat nop + concrete Abstract{} = error "Need concrete address at this stage." + concrete (Concrete addr) = addr + +-- | Gets a synthesizer program from a native program. Currently does +-- not support jumps. +fromNative :: NativeProgram -> Program +fromNative = fixNumbers . concatMap extract + where extract (Instrs a b c d) = [Opcode a, Opcode b, Opcode c, Opcode d] + extract (Jump3 a b c addr) = [Opcode a, Opcode b, Jump c $ Concrete addr] + extract (Jump2 a b addr) = [Opcode a, Jump b $ Concrete addr] + extract (Jump1 a addr) = [Jump a $ Concrete addr] + extract (Constant n) = [Number n] + fixNumbers [] = [] + fixNumbers (Opcode FetchP : rest) = case find isNumber rest of + Just n -> n : (fixNumbers $ rest \\ [n]) + Nothing -> Opcode FetchP : fixNumbers rest + fixNumbers (x : rest) = x : fixNumbers rest + isNumber Number{} = True + isNumber _ = False + +-- | Runs a given program from the default starting state. +runProgram :: State -> Program -> State +runProgram start = runNativeProgram start . toNative + +-- | Loads the given synthesizer-friendly program into the given +-- state. +load :: Program -> State -> State +load prog state = setProgram 0 (toNative prog) state diff --git a/src/Language/ArrayForth/Stack.hs b/src/Language/ArrayForth/Stack.hs new file mode 100644 --- /dev/null +++ b/src/Language/ArrayForth/Stack.hs @@ -0,0 +1,31 @@ +{-# LANGUAGE BangPatterns #-} +module Language.ArrayForth.Stack (empty, push, pop, fill, Stack) where + +import Prelude hiding ((++)) + +import Data.List (foldl') +import Data.Vector.Unboxed ((!), (++)) +import qualified Data.Vector.Unboxed as V + +import Language.ArrayForth.Opcode (F18Word) + +newtype Stack = Stack (V.Vector Int) deriving (Eq) + +instance Show Stack where show (Stack body) = unwords . map show $ V.toList body + +-- | A stack containing only 0s. +empty :: Stack +empty = Stack $ V.replicate 8 0 + +-- | Pushes the given element on top of the stack, discarding the last element. +push :: Stack -> F18Word -> Stack +push !(Stack body) word = Stack . V.cons (fromIntegral word) $ V.init body + +-- | Pops the top of the stack, returning the value and the new stack. +pop :: Stack -> (Stack, F18Word) +pop !(Stack body) = let x = V.take 1 body in (Stack $ V.tail body ++ x, fromIntegral $ x ! 0) + +-- | Push the given elements onto the stack one-by-one. +fill :: Stack -> [F18Word] -> Stack +fill = foldl' push + diff --git a/src/Language/ArrayForth/State.hs b/src/Language/ArrayForth/State.hs new file mode 100644 --- /dev/null +++ b/src/Language/ArrayForth/State.hs @@ -0,0 +1,78 @@ +{-# LANGUAGE NamedFieldPuns #-} +module Language.ArrayForth.State where + +import Data.Functor ((<$>)) +import Data.Vector.Unboxed (Vector, (//)) +import qualified Data.Vector.Unboxed as V + +import Text.Printf (printf) + +import Language.ArrayForth.NativeProgram +import Language.ArrayForth.Opcode (F18Word) +import Language.ArrayForth.Stack + +-- | The chip's RAM and ROM +type Memory = Vector Int + +emptyMem :: Memory +emptyMem = V.replicate 64 0 + +-- | A state representing the registers, stacks and memory of a core. +data State = + State { a, b, i, p, r, s, t :: !F18Word + , dataStack, returnStack :: !Stack + , memory :: !Memory } + +instance Show State where + show State {p, a, b, r, s, t, dataStack} = + printf "p:%s a:%s b:%s r:%s\n %s %s %s" p' a' b' r' t' s' (show dataStack) + where [p', a', b', r', s', t'] = map show [p, a, b, r, s, t] + +-- | The state corresponding to a core with no programs loaded and no +-- instructions executed. +startState :: State +startState = State 0 0 0 0 0 0 0 empty empty emptyMem + +-- | The next word of instructions to execute in the given state. +next :: State -> Instrs +next State {memory, p} = fromBits $ memory ! p + +-- | Pops the data stack of the given state, updating s and t. +dpop :: State -> (State, F18Word) +dpop state@State {s, t, dataStack} = + let (ds', res) = pop dataStack in (state {t = s, s = res, dataStack = ds'}, t) + +-- | Push a word onto the data stack, updating s and t. +dpush :: State -> F18Word -> State +dpush state@State {s, t, dataStack} word = + state {t = word, s = t, dataStack = push dataStack s} + +-- | Pops the return stack of the given state, updating r. +rpop :: State -> (State, F18Word) +rpop state@State {r, returnStack} = + let (rs', res) = pop returnStack in (state {r = res, returnStack = rs'}, r) + +-- | Push a word onto the return stack, updating r. +rpush :: State -> F18Word -> State +rpush state@State {r, returnStack} word = + state {r = word, returnStack = push returnStack r} + +-- | Force an address to be in range of memory: [0,64). +toMem :: (Integral a, Integral b) => a -> b +toMem = fromIntegral . (`mod` 64) + +-- | Read the memory at a location given by a Forth word. +(!) :: Memory -> F18Word -> F18Word +memory ! i | toMem i < V.length memory = fromIntegral $ memory V.! toMem i + | otherwise = error "Memory out of bounds." + +-- | Set the memory using Forth words. +set :: Memory -> F18Word -> F18Word -> Memory +set mem index value = mem // [(toMem index, fromIntegral $ value)] + +-- | Loads the given program into memory at the given starting +-- position. +setProgram :: F18Word -> NativeProgram -> State -> State +setProgram start program state@State {memory} = state' {i = toBits $ next state'} + where state' = state {memory = memory // prog} + prog = zip [toMem start..] (fromIntegral . toBits <$> program) diff --git a/src/Language/ArrayForth/Synthesis.hs b/src/Language/ArrayForth/Synthesis.hs new file mode 100644 --- /dev/null +++ b/src/Language/ArrayForth/Synthesis.hs @@ -0,0 +1,65 @@ +{-# LANGUAGE FlexibleInstances #-} +{-# LANGUAGE NamedFieldPuns #-} +{-# LANGUAGE OverlappingInstances #-} +{-# LANGUAGE ScopedTypeVariables #-} +{-# LANGUAGE TypeSynonymInstances #-} +module Language.ArrayForth.Synthesis where + +import Control.Arrow (first) +import Control.Monad.Random (Random, random, randomR) + +import Data.Functor ((<$>)) +import Data.List (genericLength, (\\)) + +import Language.ArrayForth.Distance +import Language.ArrayForth.Interpreter +import Language.ArrayForth.Opcode +import Language.ArrayForth.Program +import Language.ArrayForth.State + +import Language.Synthesis.Distribution (Distr (..), mix, + negativeInfinity, randInt, + uniform) +import Language.Synthesis.Mutations hiding (mix) +import qualified Language.Synthesis.Mutations as M + +-- | Given a specification program and some inputs, evaluate a program +-- against the specification for both performance and correctness. +evaluate :: Program -> [State] -> Distance -> Program -> Double +evaluate spec inputs score program = + 0.1 * (10 * sum correctness + sum performance / genericLength inputs) + where specs = stepProgram . load spec <$> inputs + progs = stepProgram . load program <$> inputs + cases = zip3 (last <$> specs) (length <$> specs) (countTime <$> specs) + (correctness, performance) = unzip $ zipWith test progs cases + test prog (output, steps, time) = case throttle steps prog of + Right res -> calc res + Left res -> let (a, b) = calc res in (a - 1e10, b - 1e10) + where calc res = (-score output (last res), time - countTime res) + +-- I need this so that I can get a distribution over Forth words. +instance Random F18Word where + randomR (start, end) gen = + first fromInteger $ randomR (fromIntegral start, fromIntegral end) gen + random = randomR (0, maxBound) + +-- | The default distribution of instructions. For now, we do not +-- support any sort of jumps. All the other possible instructions +-- along with constant numbers and unused slots are equally +-- likely. The numeric value of constants is currently a uniform +-- distribution over 18-bit words. +defaultOps :: Distr Instruction +defaultOps = mix [(constants, 1.0), (uniform [Unused], 1.0), + (uniform instrs, genericLength instrs)] + where instrs = map Opcode $ filter (not . isJump) opcodes \\ [Unext, Exec, Ret] + constants = let Distr {sample, logProbability} = randInt (0, maxBound) + logProb (Number n) = logProbability n + logProb _ = negativeInfinity in + Distr { sample = Number <$> sample + , logProbability = logProb } + +-- | The default mutations to try. For now, this will either change an +-- instruction or swap two instructions in the program, with equal +-- probability. +defaultMutations :: Mutation Program +defaultMutations = M.mix [(mutateInstruction defaultOps, 1), (swapInstructions, 1)] diff --git a/src/Main.hs b/src/Main.hs new file mode 100644 --- /dev/null +++ b/src/Main.hs @@ -0,0 +1,44 @@ +module Main where + +import Control.Monad.Random (evalRandIO) + +import Data.List (find) + +import Language.ArrayForth.Distance (Distance, registers) +import Language.ArrayForth.Interpreter (eval) +import Language.ArrayForth.Parse () +import Language.ArrayForth.Program (Program, load) +import Language.ArrayForth.State (State (..), startState) +import Language.ArrayForth.Synthesis (defaultMutations, defaultOps, + evaluate) + +import qualified Language.Synthesis.Distribution as Distr +import Language.Synthesis.Synthesis (Problem (..), runningBest, + synthesizeMhList) + +main :: IO () +main = verbose + +good :: (Program, Double) -> Bool +good (_, val) = val >= 0.5 + +verbose :: IO () +verbose = do ls <- evalRandIO (synthesizeMhList inclusiveOr) + mapM_ print . zip ls . takeWhile (not . good) $ runningBest ls + +run :: IO () +run = evalRandIO (synthesizeMhList inclusiveOr) >>= print . find good . runningBest + +test :: Distance -> String -> String -> State -> Double +test distance p₁ p₂ input = let r₁ = eval $ load (read p₁) input + r₂ = eval $ load (read p₂) input in + distance r₁ r₂ + +inclusiveOr :: Problem Program +inclusiveOr = Problem { score = evaluate program cases distance + , prior = Distr.replicate 8 defaultOps + , jump = defaultMutations } + where program = read "over over or a! and a or" + cases = [startState {t = 0, s = 123}, startState {t = maxBound, s = 123}, + startState {t = 1, s = 123}, startState {t = maxBound - 1, s = 123}] + distance = registers [t] diff --git a/src/Run.hs b/src/Run.hs new file mode 100644 --- /dev/null +++ b/src/Run.hs @@ -0,0 +1,46 @@ +{-# LANGUAGE NamedFieldPuns #-} +module Main where + +import Data.Functor ((<$)) +import Data.List.Split (chunk) +import qualified Data.Vector.Unboxed as V + +import Language.ArrayForth.Interpreter (eval, runNativeProgram) +import Language.ArrayForth.Parse (isNumber) +import Language.ArrayForth.Program (toNative, readProgram) +import Language.ArrayForth.State (State (..), setProgram, + startState) + +import System.Environment (getArgs) +import System.IO (hFlush, stdout) + +import Text.Printf (printf) + +main :: IO () +main = do args <- getArgs + case args of + [] -> repl + [file] -> readFile file >>= print . runNativeProgram startState . read + _ -> putStrLn $ "Too many arguments!" + +repl :: IO () +repl = go 0 startState + where go loc state = + do inp <- putStr "λ>" >> hFlush stdout >> getLine + case inp of + [':'] -> putStrLn "Please specify a command!" >> go loc state + ':' : commands -> let command : args = words commands in + run command args >>= uncurry go + program -> execute $ readProgram program + where execute (Left err) = print err >> go loc state + execute (Right program) = print res >> go p res + where res@State {p} = eval $ setProgram loc (toNative program) state + run "reset" _ = (0, startState) <$ print startState + run "p" args + | null args || not (isNumber $ head args) = + (loc, state) <$ putStrLn "Invalid arguments!" + | otherwise = let n = read $ head args in + (n, state { p = n }) <$ print state { p = n } + run cmd args = (loc, state) <$ continue cmd args + continue "memory" _ = mapM_ print . chunk 8 . V.toList $ memory state + continue cmd _ = printf "Unknown command `%s'!\n" cmd