{-# LANGUAGE OverloadedStrings #-}
module Mate.BasicBlocks(
BlockID,
- BasicBlock (..),
- BBEnd (..),
+ BasicBlock,
+ BBEnd,
MapBB,
+ Method,
printMapBB,
- parseMethod
+ parseMethod,
+ testCFG -- added by hs to perform benches from outside
)where
import Data.Binary
import Data.Int
-import qualified Data.Map as H
-import System.Environment
+import Data.List
import qualified Data.Map as M
import qualified Data.ByteString.Lazy as B
+import Data.Maybe
-import JVM.Common
import JVM.ClassFile
import JVM.Converter
-import JVM.Dump
import JVM.Assembler
-import Debug.Trace
-
+import Mate.Types
+import Mate.Debug
import Mate.Utilities
-type Name = String -- use "virtual register id" instead?
-data Type = JInt | JFloat -- add more
-type Variable = (Type,Name)
-
-type BlockID = Int
--- Represents a CFG node
-data BasicBlock = BasicBlock {
- -- inputs :: [Variable],
- -- outputs :: [Variable],
- code :: [Instruction],
- successor :: BBEnd }
-
--- describes (leaving) edges of a CFG node
-data BBEnd = Return | OneTarget BlockID | TwoTarget BlockID BlockID deriving Show
-
-type MapBB = H.Map BlockID BasicBlock
-
--- for immediate representation for determine BBs
+-- for immediate representation to determine BBs
type Offset = (Int, Maybe BBEnd) -- (offset in bytecode, offset to jump target)
type OffIns = (Offset, Instruction)
-printMapBB :: Maybe MapBB -> IO ()
-printMapBB Nothing = putStrLn "No BasicBlock"
-printMapBB (Just hmap) = do
- putStr "BlockIDs: "
- let keys = fst $ unzip $ H.toList hmap
- mapM_ (putStr . (flip (++)) ", " . show) keys
- putStrLn "\n\nBasicBlocks:"
- printMapBB' keys hmap
- where
- printMapBB' :: [BlockID] -> MapBB -> IO ()
- printMapBB' [] _ = return ()
- printMapBB' (i:is) hmap = case H.lookup i hmap of
- Just bb -> do
- putStrLn $ "Block " ++ (show i)
- mapM_ putStrLn (map ((++) "\t" . show) $ code bb)
- case successor bb of
- Return -> putStrLn ""
- OneTarget t1 -> putStrLn $ "Sucessor: " ++ (show t1) ++ "\n"
- TwoTarget t1 t2 -> putStrLn $ "Sucessor: " ++ (show t1) ++ ", " ++ (show t2) ++ "\n"
- printMapBB' is hmap
- Nothing -> error $ "BlockID " ++ show i ++ " not found."
-
-testInstance :: String -> B.ByteString -> IO ()
-testInstance cf method = do
- hmap <- parseMethod cf method
- printMapBB hmap
-
+printMapBB :: MapBB -> IO ()
+printMapBB hmap = do
+ printfBb "BlockIDs: "
+ let keys = M.keys hmap
+ mapM_ (printfBb . flip (++) ", " . show) keys
+ printfBb "\n\nBasicBlocks:\n"
+ printMapBB' keys hmap
+ where
+ printMapBB' :: [BlockID] -> MapBB -> IO ()
+ printMapBB' [] _ = return ()
+ printMapBB' (i:is) hmap' = case M.lookup i hmap' of
+ Just bb -> do
+ printfBb $ "Block " ++ show i ++ "\n"
+ mapM_ (printfBb . flip (++) "\n" . (++) "\t" . show) $ code bb
+ printfBb $ case successor bb of
+ Return -> ""
+ FallThrough t1 -> "Sucessor: " ++ show t1 ++ "\n"
+ OneTarget t1 -> "Sucessor: " ++ show t1 ++ "\n"
+ TwoTarget t1 t2 -> "Sucessor: " ++ show t1 ++ ", " ++ show t2 ++ "\n"
+ printMapBB' is hmap
+ Nothing -> error $ "BlockID " ++ show i ++ " not found."
+
+{-
+testInstance :: String -> B.ByteString -> MethodSignature -> IO ()
+testInstance cf method sig = do
+ cls <- parseClassFile cf
+ hmap <- parseMethod cls method sig
+ printMapBB hmap
+
+test_main :: IO ()
+test_main = do
+ test_01
+ test_02
+ test_03
+ test_04
+
+test_01, test_02, test_03, test_04 :: IO ()
test_01 = testInstance "./tests/Fib.class" "fib"
test_02 = testInstance "./tests/While.class" "f"
test_03 = testInstance "./tests/While.class" "g"
-
-
-parseMethod :: String -> B.ByteString -> IO (Maybe MapBB)
-parseMethod clspath method = do
- cls <- parseClassFile clspath
- return $ testCFG $ lookupMethod method cls
-
-
-testCFG :: Maybe (Method Resolved) -> Maybe MapBB
-testCFG (Just m) = case attrByName m "Code" of
- Nothing -> Nothing
- Just bytecode -> let code = decodeMethod bytecode
- instructions = codeInstructions code
- in Just $ buildCFG instructions
-testCFG _ = Nothing
-
+test_04 = testInstance "./tests/Fac.class" "fac"
+-}
+
+
+parseMethod :: Class Direct -> B.ByteString -> MethodSignature -> IO RawMethod
+parseMethod cls methodname sig = do
+ let method = fromMaybe
+ (error $ "method " ++ (show . toString) methodname ++ " not found")
+ (lookupMethodSig methodname sig cls)
+ let codeseg = fromMaybe
+ (error $ "codeseg " ++ (show . toString) methodname ++ " not found")
+ (attrByName method "Code")
+ let decoded = decodeMethod codeseg
+ let mapbb = testCFG decoded
+ let locals = fromIntegral (codeMaxLocals decoded)
+ let stacks = fromIntegral (codeStackSize decoded)
+ let codelen = fromIntegral (codeLength decoded)
+ let methoddirect = methodInfoToMethod (MethodInfo methodname "" sig) cls
+ let isStatic = methodIsStatic methoddirect
+ let nametype = methodNameType methoddirect
+ let argscount = methodGetArgsCount nametype + (if isStatic then 0 else 1)
+
+ let msig = methodSignature method
+ printfBb $ printf "BB: analysing \"%s\"\n" $ toString (methodname `B.append` ": " `B.append` encode msig)
+ printMapBB mapbb
+ -- small example how to get information about
+ -- exceptions of a method
+ -- TODO: remove ;-)
+ let (Just m) = lookupMethodSig methodname sig cls
+ case attrByName m "Code" of
+ Nothing ->
+ printfBb $ printf "exception: no handler for this method\n"
+ Just exceptionstream ->
+ printfBb $ printf "exception: \"%s\"\n" (show $ codeExceptions $ decodeMethod exceptionstream)
+ return $ RawMethod mapbb locals stacks argscount codelen
+
+
+testCFG :: Code -> MapBB
+testCFG = buildCFG . codeInstructions
buildCFG :: [Instruction] -> MapBB
-buildCFG xs = buildCFG' H.empty xs' xs'
+buildCFG xs = buildCFG' M.empty xs' xs'
where
xs' :: [OffIns]
- xs' = calculateInstructionOffset xs
+ xs' = markBackwardTargets $ calculateInstructionOffset xs
+
+-- get already calculated jmp-targets and mark the predecessor of the
+-- target-instruction as "FallThrough". we just care about backwards
+-- jumps here (forward jumps are handled in buildCFG')
+markBackwardTargets :: [OffIns] -> [OffIns]
+markBackwardTargets [] = []
+markBackwardTargets (x:[]) = [x]
+markBackwardTargets insns@(x@((x_off,x_bbend),x_ins):y@((y_off,_),_):xs) =
+ x_new:markBackwardTargets (y:xs)
+ where
+ x_new = if isTarget then checkX y_off else x
+ checkX w16 = case x_bbend of
+ Just _ -> x -- already marked, don't change
+ Nothing -> ((x_off, Just $ FallThrough w16), x_ins) -- mark previous insn
+
+ -- look through all remaining insns in the stream if there is a jmp to `y'
+ isTarget = case find cmpOffset insns of Just _ -> True; Nothing -> False
+ cmpOffset ((_,Just (OneTarget w16)),_) = w16 == y_off
+ cmpOffset ((_,Just (TwoTarget _ w16)),_) = w16 == y_off
+ cmpOffset _ = False
+
buildCFG' :: MapBB -> [OffIns] -> [OffIns] -> MapBB
buildCFG' hmap [] _ = hmap
buildCFG' hmap (((off, entry), _):xs) insns = buildCFG' (insertlist entryi hmap) xs insns
where
- insertlist :: [BlockID] -> MapBB -> MapBB
- insertlist [] hmap = hmap
- insertlist (x:xs) hmap = insertlist xs newhmap
- where
- newhmap = if H.member x hmap then hmap else H.insert x value hmap
- value = parseBasicBlock x insns
-
- entryi :: [BlockID]
- entryi = (if off == 0 then [0] else []) ++ -- also consider the entrypoint
- case entry of
- Just (TwoTarget t1 t2) -> [t1, t2]
- Just (OneTarget t) -> [t]
- Just (Return) -> []
- Nothing -> []
+ insertlist :: [BlockID] -> MapBB -> MapBB
+ insertlist [] hmap' = hmap'
+ insertlist (y:ys) hmap' = insertlist ys newhmap
+ where
+ newhmap = if M.member y hmap' then hmap' else M.insert y value hmap'
+ value = parseBasicBlock y insns
+ entryi :: [BlockID]
+ entryi = if off == 0 then 0:ys else ys -- also consider the entrypoint
+ where
+ ys = case entry of
+ Just (TwoTarget t1 t2) -> [t1, t2]
+ Just (OneTarget t) -> [t]
+ Just (FallThrough t) -> [t]
+ Just Return -> []
+ Nothing -> []
parseBasicBlock :: Int -> [OffIns] -> BasicBlock
parseBasicBlock i insns = BasicBlock insonly endblock
where
- startlist = dropWhile (\((x,_),_) -> x < i) insns
- (Just ((_,(Just endblock)),_), is) = takeWhilePlusOne validins startlist
- insonly = snd $ unzip is
+ startlist = dropWhile (\((x,_),_) -> x < i) insns
+ (Just ((_, Just endblock),_), is) = takeWhilePlusOne validins startlist
+ insonly = snd $ unzip is
- -- also take last (non-matched) element and return it
- takeWhilePlusOne :: (a -> Bool) -> [a] -> (Maybe a,[a])
- takeWhilePlusOne _ [] = (Nothing,[])
- takeWhilePlusOne p (x:xs)
- | p x = let (lastins, list) = takeWhilePlusOne p xs in (lastins, (x:list))
- | otherwise = (Just x,[x])
+ -- also take last (non-matched) element and return it
+ takeWhilePlusOne :: (a -> Bool) -> [a] -> (Maybe a,[a])
+ takeWhilePlusOne _ [] = (Nothing,[])
+ takeWhilePlusOne p (x:xs)
+ | p x = let (lastins, list) = takeWhilePlusOne p xs in (lastins, x:list)
+ | otherwise = (Just x,[x])
- validins :: ((Int, Maybe BBEnd), Instruction) -> Bool
- validins ((_,x),_) = case x of Just _ -> False; Nothing -> True
+ validins :: ((Int, Maybe BBEnd), Instruction) -> Bool
+ validins ((_,x),_) = case x of Just _ -> False; Nothing -> True
calculateInstructionOffset :: [Instruction] -> [OffIns]
calculateInstructionOffset = cio' (0, Nothing)
where
- newoffset :: Instruction -> Int -> Offset
- newoffset x off = (off + (fromIntegral $ B.length $ encodeInstructions [x]), Nothing)
-
- addW16Signed :: Int -> Word16 -> Int
- addW16Signed i w16 = i + (fromIntegral s16)
- where s16 = (fromIntegral w16) :: Int16
-
- cio' :: Offset -> [Instruction] -> [OffIns]
- cio' _ [] = []
- -- TODO(bernhard): add more instruction with offset (IF_ACMP, JSR, ...)
- cio' (off,_) (x:xs) = case x of
- IF _ w16 -> twotargets w16
- IF_ICMP _ w16 -> twotargets w16
- GOTO w16 -> onetarget w16
- IRETURN -> notarget
- _ -> ((off, Nothing), x):next
- where
- notarget = ((off, Just Return), x):next
- onetarget w16 = ((off, Just $ OneTarget $ (off `addW16Signed` w16)), x):next
- twotargets w16 = ((off, Just $ TwoTarget (off `addW16Signed` w16) (off + 3)), x):next
- next = cio' (newoffset x off) xs
+ newoffset :: Instruction -> Int -> Offset
+ newoffset x off = (off + fromIntegral (B.length $ encodeInstructions [x]), Nothing)
+
+ addW16Signed :: Int -> Word16 -> Int
+ addW16Signed i w16 = i + fromIntegral s16
+ where s16 = fromIntegral w16 :: Int16
+
+ cio' :: Offset -> [Instruction] -> [OffIns]
+ cio' _ [] = []
+ -- TODO(bernhard): add more instruction with offset (IF_ACMP, JSR, ...)
+ cio' (off,_) (x:xs) = case x of
+ IF _ w16 -> twotargets w16
+ IF_ICMP _ w16 -> twotargets w16
+ IF_ACMP _ w16 -> twotargets w16
+ IFNONNULL w16 -> twotargets w16
+ IFNULL w16 -> twotargets w16
+ GOTO w16 -> onetarget w16
+ IRETURN -> notarget
+ ARETURN -> notarget
+ RETURN -> notarget
+ _ -> ((off, Nothing), x):next
+ where
+ notarget = ((off, Just Return), x):next
+ onetarget w16 = ((off, Just $ OneTarget (off `addW16Signed` w16)), x):next
+ twotargets w16 = ((off, Just $ TwoTarget (off + 3) (off `addW16Signed` w16)), x):next
+ next = cio' (newoffset x off) xs