+{-# LANGUAGE CPP #-}
{-# LANGUAGE OverloadedStrings #-}
+#include "debug.h"
module Mate.BasicBlocks(
BlockID,
BasicBlock (..),
BBEnd (..),
MapBB,
+#ifdef DBG_BB
printMapBB,
+#endif
parseMethod,
- test_main
+ testCFG -- added by hs to perform benches from outside
)where
import Data.Binary
import Data.Int
+import Data.List
import qualified Data.Map as M
import qualified Data.ByteString.Lazy as B
import JVM.Converter
import JVM.Assembler
+import Mate.Types
+import Mate.Debug
import Mate.Utilities
+#ifdef DEBUG
+import Text.Printf
+#endif
-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 = M.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)
+#ifdef DBG_BB
printMapBB :: Maybe MapBB -> IO ()
printMapBB Nothing = putStrLn "No BasicBlock"
printMapBB (Just hmap) = do
putStr "BlockIDs: "
- let keys = fst $ unzip $ M.toList hmap
+ let keys = M.keys hmap
mapM_ (putStr . (flip (++)) ", " . show) keys
putStrLn "\n\nBasicBlocks:"
printMapBB' keys hmap
mapM_ putStrLn (map ((++) "\t" . show) $ code bb)
case successor bb of
Return -> putStrLn ""
+ FallThrough t1 -> putStrLn $ "Sucessor: " ++ (show t1) ++ "\n"
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."
+#endif
-testInstance :: String -> B.ByteString -> IO ()
-testInstance cf method = do
+#if 0
+#ifdef DBG_BB
+testInstance :: String -> B.ByteString -> MethodSignature -> IO ()
+testInstance cf method sig = do
cls <- parseClassFile cf
- hmap <- parseMethod cls method
+ hmap <- parseMethod cls method sig
printMapBB hmap
+#endif
+#ifdef DBG_BB
test_main :: IO ()
test_main = do
test_01
test_02
test_03
+ test_04
-test_01, test_02, test_03 :: IO ()
+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 :: Class Resolved -> B.ByteString -> IO (Maybe MapBB)
-parseMethod cls method = do
- putStr "BB: analysing: "
- let msig = methodSignature $ (classMethods cls) !! 1
- B.putStrLn (method `B.append` ": " `B.append` (encode msig))
- return $ testCFG $ lookupMethod method cls
-
-
-testCFG :: Maybe (Method Resolved) -> Maybe MapBB
-testCFG (Just m) = case attrByName m "Code" of
- Nothing -> Nothing
- Just bytecode -> Just $ buildCFG $ codeInstructions $ decodeMethod bytecode
-testCFG _ = Nothing
+test_04 = testInstance "./tests/Fac.class" "fac"
+#endif
+#endif
+
+
+parseMethod :: Class Direct -> B.ByteString -> MethodSignature -> IO (Maybe MapBB)
+parseMethod cls method sig = do
+ let maybe_bb = testCFG $ lookupMethodSig method sig cls
+ let msig = methodSignature $ classMethods cls !! 1
+ printfBb "BB: analysing \"%s\"\n" $ toString (method `B.append` ": " `B.append` encode msig)
+#ifdef DBG_BB
+ printMapBB maybe_bb
+#endif
+ -- small example how to get information about
+ -- exceptions of a method
+ -- TODO: remove ;-)
+ let (Just m) = lookupMethodSig method sig cls
+ case attrByName m "Code" of
+ Nothing -> printfBb "exception: no handler for this method\n"
+ Just exceptionstream -> printfBb "exception: \"%s\"\n" (show $ codeExceptions $ decodeMethod exceptionstream)
+ return maybe_bb
+
+
+testCFG :: Maybe (Method Direct) -> Maybe MapBB
+testCFG m = do
+ m' <- m
+ bytecode <- attrByName m' "Code"
+ return $ buildCFG $ codeInstructions $ decodeMethod bytecode
buildCFG :: [Instruction] -> MapBB
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
value = parseBasicBlock y 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 -> []
+ 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
+ (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))
+ | p x = let (lastins, list) = takeWhilePlusOne p xs in (lastins, x:list)
| otherwise = (Just x,[x])
validins :: ((Int, Maybe BBEnd), Instruction) -> Bool
calculateInstructionOffset = cio' (0, Nothing)
where
newoffset :: Instruction -> Int -> Offset
- newoffset x off = (off + (fromIntegral $ B.length $ encodeInstructions [x]), Nothing)
+ 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
+ addW16Signed i w16 = i + fromIntegral s16
+ where s16 = fromIntegral w16 :: Int16
cio' :: Offset -> [Instruction] -> [OffIns]
cio' _ [] = []
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
+ 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
projects / mate.git / blobdiff