{-# LANGUAGE OverloadedStrings #-}
-module Mate.BasicBlocks where
+module Mate.BasicBlocks(
+ BlockID,
+ BasicBlock,
+ BBEnd,
+ MapBB,
+ Method,
+ printMapBB,
+ parseMethod,
+ testCFG -- added by hs to perform benches from outside
+ )where
-import Data.Binary
-import System.Environment
+import Data.Binary hiding (get)
+import Data.Int
import qualified Data.Map as M
import qualified Data.ByteString.Lazy as B
+import Data.Maybe
+import Control.Monad.State
+import Control.Applicative
+import Control.Arrow
-import JVM.Common
import JVM.ClassFile
import JVM.Converter
-import JVM.Dump
import JVM.Assembler
+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)
+-- (offset in bytecode, offset to jump target, ins)
+type OffIns = (Int, Maybe BBEnd, Instruction)
--- Represents a CFG node
-data BasicBlock = BasicBlock {
- inputs :: [Variable],
- outputs :: [Variable],
- code :: [Instruction] }
+type Targets = [BlockID]
+type BBState = Targets
+type AnalyseState = State BBState [OffIns]
--- Represents a Control-Flow-Graph as
--- Adjacency list (add matrix representation if appropriate)
-type CFList = [(BasicBlock, [BasicBlock])]
+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."
-main = do
- args <- getArgs
- case args of
- [clspath] -> parseFile clspath "fib" -- TODO
- _ -> error "Synopsis: dump-class File.class"
+{-
+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
-parseFile :: String -> B.ByteString -> IO ()
-parseFile clspath method = do
- --clsFile <- decodeFile clspath
- --putStrLn $ showListIx $ M.assocs $ constsPool (clsFile :: Class Pointers)
- cls <- parseClassFile clspath
- --dumpClass cls
- let mainmethod = lookupMethod method cls -- "main|([Ljava/lang/String;)V" cf
- mapM_ putStrLn (testCFG mainmethod)
+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"
+test_04 = testInstance "./tests/Fac.class" "fac"
+-}
-test_01 = parseFile "./tests/Fib.class" "fib"
-test_02 = parseFile "./tests/While.class" "f"
-test_03 = parseFile "./tests/While.class" "g"
+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)
-testCFG :: Maybe (Method Resolved) -> [String]
-testCFG (Just m) = case attrByName m "Code" of
- Nothing -> error "no code"
- Just bytecode -> let code = decodeMethod bytecode
- instructions = codeInstructions code
- in buildCFG instructions
-testCFG _ = error "no method to build cfg"
+ 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
-buildCFG :: [Instruction] -> [String]
-buildCFG xs = map show xs
+testCFG :: Code -> MapBB
+testCFG = buildCFG . codeInstructions
+
+buildCFG :: [Instruction] -> MapBB
+buildCFG xs = buildCFG' M.empty xs' xs'
+ where
+ xs' :: [OffIns]
+ xs' = evalState (calculateInstructionOffset xs >>= markBackwardTargets) []
+
+-- 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] -> AnalyseState
+markBackwardTargets [] = return []
+markBackwardTargets (x:[]) = return [x]
+markBackwardTargets (x@(x_off,x_bbend,x_ins):y@(y_off,_,_):xs) = do
+ rest <- markBackwardTargets (y:xs)
+ targets <- get
+ let isTarget = y_off `elem` targets
+ 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"
+ return $ x_new:rest
+
+
+
+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 -> []
+
+
+parseBasicBlock :: Int -> [OffIns] -> BasicBlock
+parseBasicBlock i insns = BasicBlock insonly endblock
+ where
+ (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 -> 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 :: OffIns -> Bool
+ validins (_, x, _) = isNothing x
+
+ omitins :: OffIns -> Bool
+ omitins (off, _, _) = off < i
+
+
+calculateInstructionOffset :: [Instruction] -> AnalyseState
+calculateInstructionOffset = cio' (0, Nothing, NOP)
+ where
+ addW16Signed :: Int -> Word16 -> Int
+ addW16Signed i w16 = i + fromIntegral s16
+ where s16 = fromIntegral w16 :: Int16
+
+ cio' :: OffIns -> [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
+ IRETURN -> notarget
+ ARETURN -> notarget
+ RETURN -> notarget
+ _ -> ((off, Nothing, x):) <$> next
+ where
+ notarget = ((off, Just Return, x):) <$> next
+ onetarget w16 = do
+ let jump = off `addW16Signed` w16
+ modify (jump:)
+ ((off, Just $ OneTarget jump, x):) <$> next
+ twotargets w16 = do
+ let nojump = off + 3
+ modify (nojump:)
+ let jump = off `addW16Signed` w16
+ modify (jump:)
+ ((off, Just $ TwoTarget nojump jump, x):) <$> next
+ next = cio' newoffset xs
+ newoffset = (off + insnLength x, Nothing, NOP)
+
+-- 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 . (:[])