Split into modules.

build.sh

@@ -1,4 +1,3 @@
 #!/bin/sh
 
-mkdir -p bin
-ghc src/Main.hs -o bin/sixtypical
+cd src && mkdir -p ../bin && ghc Main.hs -o ../bin/sixtypical

src/Main.hs

@@ -2,243 +2,13 @@
 
 module Main where
 
-import qualified Data.Map as Map
-
 import System.IO
 import System.Environment
 import System.Exit
 
-import Text.ParserCombinators.Parsec
-
--- -- -- -- machine model -- -- -- --
-
-type Address = Int -- LET'S ASSUME THIS IS AT LEAST 16 BITS
-
-type LocationName = String
-
-data Register = A | X | Y    -- | MemLoc LocationName
-    deriving (Show, Ord, Eq)
-
-allRegisters = [A, X, Y]
-
--- -- -- -- program model -- -- -- --
-
-data Size = Byte
-          | Word
-    deriving (Show, Ord, Eq)
-
-data Decl = Assign LocationName Size Address -- .alias
-          | Reserve LocationName Size -- .word, .byte
-    deriving (Show, Ord, Eq)
-
-type RoutineName = String
-
-data Instruction = LOAD Register LocationName
-                 | COPY Register Register
-                 | CMP Register LocationName
-                 | JSR RoutineName
-                 | IFEQ [Instruction] [Instruction]
-                 | NOP
-    deriving (Show, Ord, Eq)
-
-data Routine = Routine RoutineName [Instruction]
-    deriving (Show, Ord, Eq)
-
-data Program = Program [Decl] [Routine]
-    deriving (Show, Ord, Eq)
-
--- -- -- -- data-flow-analysis context -- -- -- --
-
-data Usage = Unknown
-           | Value LocationName -- obviously a bit daft for now
-           | Retained Register
-    deriving (Show, Ord, Eq)
-
-type RoutineContext = Map.Map Register Usage
-
-type ProgramContext = Map.Map RoutineName RoutineContext
-
---
--- Utility function:
--- Take 2 routine contexts -- the current routine and a routine that was just
--- JSR'ed to (immediately previously) -- and merge them to create a new
--- context for the current routine.
---
-mergeRoutCtxs routCtx calledRoutCtx =
-    let
-        -- insert the values into routCtx
-        -- TODO, first compare them
-        -- TODO, if not equal, 'poison' them
-        -- TODO, other special cases (eg Unknown)
-        poison key value routCtxAccum =
-            case value of
-                -- if the called routine retains it,
-                -- we keep our idea of it -- but TODO
-                -- should we mark it "was retained"?
-                Retained reg ->
-                    routCtxAccum
-                _ ->
-                    Map.insert key value routCtxAccum
-    in
-        Map.foldrWithKey (poison) routCtx calledRoutCtx
-
--- -- -- -- static analyzer -- -- -- --
-
-checkProgram (Program decls routines) =
-    checkRoutines routines Map.empty
-
-checkRoutines [] progCtx = progCtx
-checkRoutines (rout@(Routine name _) : routs) progCtx =
-    let
-        routCtx = Map.fromList $ map (\reg -> (reg, Retained reg)) allRegisters
-        routAnalysis = checkRoutine rout progCtx routCtx
-        progCtx' = Map.insert name routAnalysis progCtx
-    in
-        checkRoutines routs progCtx'
-
-checkRoutine (Routine _ []) progCtx routCtx = routCtx
-checkRoutine (Routine name (instr : instrs)) progCtx routCtx =
-    let
-        routCtx' = checkInstr instr progCtx routCtx
-    in
-        checkRoutine (Routine name instrs) progCtx routCtx'
-
-checkInstr (LOAD reg addr) progCtx routCtx =
-    Map.insert reg (Value addr) routCtx
-checkInstr (COPY src dst) progCtx routCtx =
-    Map.insert dst (Map.findWithDefault Unknown src routCtx) routCtx
-checkInstr (JSR name) progCtx routCtx =
-    case Map.lookup name progCtx of
-        Just calledRoutCtx ->
-            mergeRoutCtxs routCtx calledRoutCtx
-        Nothing ->
-            error ("can't call routine '" ++ name ++ "' before it is defined")
-checkInstr (CMP reg addr) progCtx routCtx =
-    -- TODO: mark Carry bit as "touched" here
-    routCtx
-checkInstr (IFEQ b1 b2) progCtx routCtx =
-    -- TODO: oooh, this one's gonna be fun
-    routCtx
-checkInstr NOP progCtx routCtx =
-    routCtx
-
--- -- -- -- parser -- -- -- --
-{-
-
-Toplevel := {Decl} {Routine}.
-Decl     := "reserve" Size LocationName
-          | "assign" Size LocationName Address.
-Size     := "byte" | "word".
-Routine  := "routine" RoutineName Block.
-Block    := "{" {Command} "}".
-Command  := "beq" Block "else" Block
-          | "lda" (LocationName | Immediate)
-          | "txa" | "tax" | "tya" | "tay"
-          | "cmp" (LocationName | Immediate)
-
--}
-
-toplevel :: Parser Program
-toplevel = do
-    decls <- many (assign <|> try reserve)
-    routines <- many routine
-    return $ Program decls routines
-
-reserve :: Parser Decl
-reserve = do
-    string "reserve"
-    spaces
-    sz <- size
-    spaces  -- size does not do its own spacesising
-    name <- locationName
-    return $ Reserve name sz
-
-assign :: Parser Decl
-assign = do
-    string "assign"
-    spaces
-    sz <- size
-    spaces  -- size does not do its own spacesising
-    name <- locationName
-    addr <- address
-    return $ Assign name sz addr
-
-size :: Parser Size
-size = do
-    s <- (string "byte") <|> (string "word")
-    return $ case s of
-        "byte" -> Byte
-        "word" -> Word
-
-routine :: Parser Routine
-routine = do
-    string "routine"
-    spaces
-    name <- routineName
-    instrs <- block
-    return (Routine name instrs)
-
-block :: Parser [Instruction]
-block = do
-    string "{"
-    spaces
-    cs <- many command
-    string "}"
-    spaces
-    return cs
-
-command :: Parser Instruction
-command = cmp <|> lda <|> beq <|> nop
-
-nop :: Parser Instruction
-nop = do
-    string "nop"
-    spaces
-    return NOP
-
-cmp :: Parser Instruction
-cmp = do
-    string "cmp"
-    spaces
-    l <- locationName
-    return (CMP A l)
-
-lda :: Parser Instruction
-lda = do
-    string "lda"
-    spaces
-    l <- locationName
-    return (LOAD A l)
-
-beq :: Parser Instruction
-beq = do
-    string "beq"
-    spaces
-    b1 <- block
-    string "else"
-    spaces
-    b2 <- block
-    return (IFEQ b1 b2)
-
-routineName :: Parser String
-routineName = do
-    c <- letter
-    cs <- many (alphaNum <|> char '_')
-    spaces
-    return (c:cs)
-
-locationName :: Parser String
-locationName = do
-    c <- letter
-    cs <- many (alphaNum <|> char '_')
-    spaces
-    return (c:cs)
-
-address :: Parser Address
-address = do
-    digits <- many digit
-    spaces
-    return (read digits :: Address)
+import SixtyPical.Parser (parseProgram)
+import SixtyPical.Model
+import SixtyPical.Context (checkProgram)
 
 -- -- -- -- driver -- -- -- --
 
@@ -251,7 +21,7 @@ main = do
     case args of
         [verb, filename] -> do
             programText <- readFile filename
-            case (verb, parse toplevel "" programText) of
+            case (verb, parseProgram programText) of
                 ("parse", Right program) -> do
                     putStrLn $ show $ program
                 ("check", Right program) -> do

src/SixtyPical/Context.hs

@@ -0,0 +1,80 @@
+module SixtyPical.Context where
+
+import qualified Data.Map as Map
+
+import SixtyPical.Model
+
+-- -- -- -- data-flow-analysis context -- -- -- --
+
+data Usage = Unknown
+           | Value LocationName -- obviously a bit daft for now
+           | Retained Register
+    deriving (Show, Ord, Eq)
+
+type RoutineContext = Map.Map Register Usage
+
+type ProgramContext = Map.Map RoutineName RoutineContext
+
+--
+-- Utility function:
+-- Take 2 routine contexts -- the current routine and a routine that was just
+-- JSR'ed to (immediately previously) -- and merge them to create a new
+-- context for the current routine.
+--
+mergeRoutCtxs routCtx calledRoutCtx =
+    let
+        -- insert the values into routCtx
+        -- TODO, first compare them
+        -- TODO, if not equal, 'poison' them
+        -- TODO, other special cases (eg Unknown)
+        poison key value routCtxAccum =
+            case value of
+                -- if the called routine retains it,
+                -- we keep our idea of it -- but TODO
+                -- should we mark it "was retained"?
+                Retained reg ->
+                    routCtxAccum
+                _ ->
+                    Map.insert key value routCtxAccum
+    in
+        Map.foldrWithKey (poison) routCtx calledRoutCtx
+
+-- -- -- -- static analyzer -- -- -- --
+
+checkProgram (Program decls routines) =
+    checkRoutines routines Map.empty
+
+checkRoutines [] progCtx = progCtx
+checkRoutines (rout@(Routine name _) : routs) progCtx =
+    let
+        routCtx = Map.fromList $ map (\reg -> (reg, Retained reg)) allRegisters
+        routAnalysis = checkRoutine rout progCtx routCtx
+        progCtx' = Map.insert name routAnalysis progCtx
+    in
+        checkRoutines routs progCtx'
+
+checkRoutine (Routine _ []) progCtx routCtx = routCtx
+checkRoutine (Routine name (instr : instrs)) progCtx routCtx =
+    let
+        routCtx' = checkInstr instr progCtx routCtx
+    in
+        checkRoutine (Routine name instrs) progCtx routCtx'
+
+checkInstr (LOAD reg addr) progCtx routCtx =
+    Map.insert reg (Value addr) routCtx
+checkInstr (COPY src dst) progCtx routCtx =
+    Map.insert dst (Map.findWithDefault Unknown src routCtx) routCtx
+checkInstr (JSR name) progCtx routCtx =
+    case Map.lookup name progCtx of
+        Just calledRoutCtx ->
+            mergeRoutCtxs routCtx calledRoutCtx
+        Nothing ->
+            error ("can't call routine '" ++ name ++ "' before it is defined")
+checkInstr (CMP reg addr) progCtx routCtx =
+    -- TODO: mark Carry bit as "touched" here
+    routCtx
+checkInstr (IFEQ b1 b2) progCtx routCtx =
+    -- TODO: oooh, this one's gonna be fun
+    routCtx
+checkInstr NOP progCtx routCtx =
+    routCtx

src/SixtyPical/Model.hs

@@ -0,0 +1,40 @@
+-- encoding: UTF-8
+
+module SixtyPical.Model where
+
+-- -- -- -- machine model -- -- -- --
+
+type Address = Int -- LET'S ASSUME THIS IS AT LEAST 16 BITS
+
+type LocationName = String
+
+data Register = A | X | Y    -- | MemLoc LocationName
+    deriving (Show, Ord, Eq)
+
+allRegisters = [A, X, Y]
+
+-- -- -- -- program model -- -- -- --
+
+data Size = Byte
+          | Word
+    deriving (Show, Ord, Eq)
+
+data Decl = Assign LocationName Size Address -- .alias
+          | Reserve LocationName Size -- .word, .byte
+    deriving (Show, Ord, Eq)
+
+type RoutineName = String
+
+data Instruction = LOAD Register LocationName
+                 | COPY Register Register
+                 | CMP Register LocationName
+                 | JSR RoutineName
+                 | IFEQ [Instruction] [Instruction]
+                 | NOP
+    deriving (Show, Ord, Eq)
+
+data Routine = Routine RoutineName [Instruction]
+    deriving (Show, Ord, Eq)
+
+data Program = Program [Decl] [Routine]
+    deriving (Show, Ord, Eq)

src/SixtyPical/Parser.hs

@@ -0,0 +1,127 @@
+-- encoding: UTF-8
+
+module SixtyPical.Parser (parseProgram) where
+
+import SixtyPical.Model
+import Text.ParserCombinators.Parsec
+
+{-
+
+Toplevel := {Decl} {Routine}.
+Decl     := "reserve" Size LocationName
+          | "assign" Size LocationName Address.
+Size     := "byte" | "word".
+Routine  := "routine" RoutineName Block.
+Block    := "{" {Command} "}".
+Command  := "beq" Block "else" Block
+          | "lda" (LocationName | Immediate)
+          | "txa" | "tax" | "tya" | "tay"
+          | "cmp" (LocationName | Immediate)
+
+-}
+
+toplevel :: Parser Program
+toplevel = do
+    decls <- many (assign <|> try reserve)
+    routines <- many routine
+    return $ Program decls routines
+
+reserve :: Parser Decl
+reserve = do
+    string "reserve"
+    spaces
+    sz <- size
+    spaces  -- size does not do its own spacesising
+    name <- locationName
+    return $ Reserve name sz
+
+assign :: Parser Decl
+assign = do
+    string "assign"
+    spaces
+    sz <- size
+    spaces  -- size does not do its own spacesising
+    name <- locationName
+    addr <- address
+    return $ Assign name sz addr
+
+size :: Parser Size
+size = do
+    s <- (string "byte") <|> (string "word")
+    return $ case s of
+        "byte" -> Byte
+        "word" -> Word
+
+routine :: Parser Routine
+routine = do
+    string "routine"
+    spaces
+    name <- routineName
+    instrs <- block
+    return (Routine name instrs)
+
+block :: Parser [Instruction]
+block = do
+    string "{"
+    spaces
+    cs <- many command
+    string "}"
+    spaces
+    return cs
+
+command :: Parser Instruction
+command = cmp <|> lda <|> beq <|> nop
+
+nop :: Parser Instruction
+nop = do
+    string "nop"
+    spaces
+    return NOP
+
+cmp :: Parser Instruction
+cmp = do
+    string "cmp"
+    spaces
+    l <- locationName
+    return (CMP A l)
+
+lda :: Parser Instruction
+lda = do
+    string "lda"
+    spaces
+    l <- locationName
+    return (LOAD A l)
+
+beq :: Parser Instruction
+beq = do
+    string "beq"
+    spaces
+    b1 <- block
+    string "else"
+    spaces
+    b2 <- block
+    return (IFEQ b1 b2)
+
+routineName :: Parser String
+routineName = do
+    c <- letter
+    cs <- many (alphaNum <|> char '_')
+    spaces
+    return (c:cs)
+
+locationName :: Parser String
+locationName = do
+    c <- letter
+    cs <- many (alphaNum <|> char '_')
+    spaces
+    return (c:cs)
+
+address :: Parser Address
+address = do
+    digits <- many digit
+    spaces
+    return (read digits :: Address)
+
+-- -- -- driver -- -- --
+
+parseProgram = parse toplevel ""