testCFG -- added by hs to perform benches from outside
)where
-import Data.Binary
+import Data.Binary hiding (get)
import Data.Int
-import Data.List
import qualified Data.Map as M
+import qualified Data.Set as S
import qualified Data.ByteString.Lazy as B
import Data.Maybe
+import Control.Monad.State
+import Control.Applicative
+import Control.Arrow
import JVM.ClassFile
import JVM.Converter
import Mate.Debug
import Mate.Utilities
--- for immediate representation to determine BBs
-type Offset = (Int, Maybe BBEnd) -- (offset in bytecode, offset to jump target)
-type OffIns = (Offset, Instruction)
+-- (offset in bytecode, offset to jump target, ins)
+type OffIns = (Int, Maybe BBEnd, Instruction)
+type Target = BlockID
+type BBState = S.Set Target
+type AnalyseState = State BBState [OffIns]
+
+
+noException :: B.ByteString
+noException = B.empty
+
+emptyBasicBlock :: BasicBlock
+emptyBasicBlock = BasicBlock
+ { code = []
+ , exception = noException
+ , successor = Return }
printMapBB :: MapBB -> IO ()
printMapBB hmap = do
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
+ -- TODO: remove ;-)
-- 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)
+ -- [/remove]
+ let msig = methodSignature method
+ printfBb $ printf "BB: analysing \"%s\"\n" $ toString (methodname `B.append` ": " `B.append` encode msig)
+ printMapBB mapbb
return $ RawMethod mapbb locals stacks argscount codelen
testCFG :: Code -> MapBB
-testCFG = buildCFG . codeInstructions
+testCFG c = buildCFG (codeInstructions c) (codeExceptions c)
-buildCFG :: [Instruction] -> MapBB
-buildCFG xs = buildCFG' M.empty xs' xs'
+buildCFG :: [Instruction] -> [CodeException] -> MapBB
+buildCFG xs excps = execState (mapM (buildCFG' offins) $ alltargets ++ handlerEntries) M.empty
where
- xs' :: [OffIns]
- 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 = case x_bbend of
- Just _ -> x -- already marked, don't change
- Nothing -> if isTarget then checkX y_off else x
- checkX w16 = case x_bbend of
- Nothing -> ((x_off, Just $ FallThrough w16), x_ins) -- mark previous insn
- _ -> error "basicblock: something is wrong"
-
- -- 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 (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 -> []
+ (offins, targets) = runState (calculateInstructionOffset tryBlocks xs) S.empty
+ alltargets = S.toList $ S.insert 0 targets
+ tryBlocks = map (fromIntegral . eStartPC) excps
+ handlerEntries = map (fromIntegral . eHandlerPC) excps
+buildCFG' :: [OffIns] -> Int -> State MapBB ()
+buildCFG' insns off = do
+ let value = parseBasicBlock off insns
+ modify (M.insert off value)
parseBasicBlock :: Int -> [OffIns] -> BasicBlock
-parseBasicBlock i insns = BasicBlock insonly endblock
+parseBasicBlock i insns = emptyBasicBlock { code = insonly, successor = endblock }
where
- startlist = dropWhile (\((x,_),_) -> x < i) insns
- (Just ((_, Just endblock),_), is) = takeWhilePlusOne validins startlist
- insonly = snd $ unzip is
+ (lastblock, is) = takeWhilePlusOne validins omitins insns
+ (_, _, insonly) = unzip3 is
+ (_, Just endblock, _) = fromJust lastblock
-- 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])
+ takeWhilePlusOne :: (a -> Bool) -> (a -> Bool) -> [a] -> (Maybe a, [a])
+ takeWhilePlusOne _ _ [] = (Nothing, [])
+ takeWhilePlusOne p omit (x:xs)
+ | omit x = next
+ | p x = second (x:) next
+ | otherwise = (Just x, [x])
+ where
+ next = takeWhilePlusOne p omit xs
- validins :: ((Int, Maybe BBEnd), Instruction) -> Bool
- validins ((_,x),_) = case x of Just _ -> False; Nothing -> True
+ validins :: OffIns -> Bool
+ validins (_, x, _) = isNothing x
+ omitins :: OffIns -> Bool
+ omitins (off, _, _) = off < i
-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
+calculateInstructionOffset :: [BlockID] -> [Instruction] -> AnalyseState
+calculateInstructionOffset exstarts = cio' 0
+ where
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
+ cio' :: Int -> [Instruction] -> AnalyseState
+ cio' _ [] = return $ []
+ 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
+ ATHROW -> notarget
IRETURN -> notarget
ARETURN -> notarget
RETURN -> notarget
- _ -> ((off, Nothing), x):next
+ _ -> if newoffset `elem` exstarts
+ then do
+ modify (S.insert newoffset)
+ ((off, Just $ OneTarget newoffset, x):) <$> next
+ else normalins
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
+ normalins = do
+ tailinsns <- next -- eval remaining instructions
+ isNextInsATarget <- (S.member newoffset) <$> get
+ let bbtyp = if isNextInsATarget
+ then Just $ FallThrough newoffset
+ else Nothing
+ return $ (off, bbtyp, x):tailinsns
+ notarget = ((off, Just Return, x):) <$> next
+ onetarget w16 = do
+ let jump = off `addW16Signed` w16
+ modify (S.insert jump)
+ ((off, Just $ OneTarget jump, x):) <$> next
+ twotargets w16 = do
+ let nojump = off + 3
+ modify (S.insert nojump)
+ let jump = off `addW16Signed` w16
+ modify (S.insert jump)
+ ((off, Just $ TwoTarget nojump jump, x):) <$> next
+ next = cio' newoffset xs
+ newoffset = off + insLen
+ insLen = insnLength x
+
+-- TODO(bernhard): does GHC memomize results? i.e. does it calculate the size
+-- of `NOP' only once?
+insnLength :: Num a => Instruction -> a
+insnLength = fromIntegral . B.length . encodeInstructions . (:[])
projects / mate.git / blobdiff