:: SSMProgram :== [Instr]
:: GenError = Error String
:: Addressbook :== 'Map'.Map String Address
-:: Address = LAB String | ADDR Int
+:: Address = LAB String Int | ADDR Int
:: Gen a :== RWST () SSMProgram (Addressbook, [Label]) (Either GenError) a
labelStream :: [Label]
labelStream = ["lbl_" +++ toString i\\i<-[1..]]
defaultAddressBook :: Addressbook
-defaultAddressBook = extend "print" (LAB "print")
- $ extend "read" (LAB "read")
- $ extend "isEmpty" (LAB "isEmpty")
- 'Map'.newMap
+defaultAddressBook = extend "1printint" (LAB "1printint" 1)
+ $ extend "1printchar" (LAB "1printchar" 1)
+ $ extend "1readchar" (LAB "1readchar" 0)
+ $ extend "1readint" (LAB "1readint" 0)
+ $ extend "isEmpty" (LAB "isempty" 1)
+ 'Map'.newMap
gen :: AST -> Either String String
gen (AST fds) = case evalRWST prog () (defaultAddressBook, labelStream) of
>>| mapM_ g fds
programContext :: SSMProgram
-programContext = [Lab "print" //there is no actual IO in SSM
+programContext = [Lab "1printint"
,Instr "link" [Lit 0] ""
+ ,Instr "ldl" [Lit -2] "load first argument"
+ ,Instr "trap" [Lit 0] "print int"
,Instr "unlink" [] ""
,Instr "ret" [] ""
- ,Lab "read" //there is no actual IO in SSM
+ ,Lab "1printchar"
,Instr "link" [Lit 0] ""
- ,Instr "ldc" [Lit 0] ""
- ,Instr "sth" [] ""
+ ,Instr "ldl" [Lit -2] "load first argument"
+ ,Instr "trap" [Lit 1] "print char"
+ ,Instr "unlink" [] ""
+ ,Instr "ret" [] ""
+ ,Lab "1readint"
+ ,Instr "link" [Lit 0] ""
+ ,Instr "trap" [Lit 10] "read int"
,Instr "str" [Raw "RR"] ""
,Instr "unlink" [] ""
,Instr "ret" [] ""
- ,Lab "isEmpty"
+ ,Lab "1readchar"
+ ,Instr "link" [Lit 0] ""
+ ,Instr "trap" [Lit 11] "read char"
+ ,Instr "str" [Raw "RR"] ""
+ ,Instr "unlink" [] ""
+ ,Instr "ret" [] ""
+ ,Lab "isempty"
,Instr "link" [Lit 0] ""
,Instr "ldl" [Lit -2] "load prt to list"
,Instr "lda" [Lit 0] "derefrence ptr"
BiOr = "or"
BiCons = abort "Shit, Cons, how to deal with this?"
+instance g FieldSelector where
+ g FieldFst = tell [Instr "lda" [Lit 0] "fst"]
+ g FieldSnd = tell [Instr "lda" [Lit 1] "snd"]
+ g FieldHd = tell [Instr "lda" [Lit -1] "hd"]
+ g FieldTl = tell [Instr "lda" [Lit 0] "tl"]
+
instance g Expr where
g (IntExpr _ i) = tell [Instr "ldc" [Lit i] ""]
g (CharExpr _ c) = tell [Instr "ldc" [Lit (toInt c)] ""]
>>| tell [Instr "sth" [] ""]
>>| tell [Instr "ajs" [Lit -1] ""]
g (VarExpr _ (VarDef k fs)) = getAdressbook >>= \ab->case 'Map'.get k ab of
- Nothing = liftT (Left $ Error "PANIC: undefined variable")
- Just (ADDR t) = tell [Instr "ldl" [Lit t] ""]
- Just (LAB t) = liftT (Left $ Error "PANIC: variable and function name clash")
- //load k >>= \instr-> tell [instr] //note: pure is pure for list, i.e. []
+ Just (ADDR t) = tell [Instr "ldl" [Lit t] ""] >>| mapM_ g fs >>| pure ()
+ _ = liftT (Left $ Error "PANIC: variable and function name clash")
g (FunExpr _ k es fs) =
mapM_ g es
>>| jump "bsr" k
jump :: String String -> Gen ()
jump instr k = getAdressbook >>= \ab->case 'Map'.get k ab of
Nothing = liftT (Left $ Error $ concat ["PANIC: ", k, " not found as function"])
- Just (LAB t) = tell [Instr instr [L t] (k +++"()")]
+ Just (LAB t _) = tell [Instr instr [L t] (k +++"()")]
Just (ADDR t) = liftT (Left $ Error $ "PANIC: jump should go to label")
instance g Stmt where
g (AssStmt (VarDef k fs) e) =
g e >>| getAdressbook >>= \ab->case 'Map'.get k ab of
Nothing = liftT (Left $ Error $ concat ["PANIC: ", k, " not found as var"])
- Just (LAB t) = liftT (Left $ Error $ "PANIC: cannot assign to function")
+ Just (LAB t _) = liftT (Left $ Error $ "PANIC: cannot assign to function")
Just (ADDR t) = tell [Instr "stl" [Lit t] ""]
- g (FunStmt k es) = mapM_ g es
+ g (FunStmt k es fs) = mapM_ g es
>>| jump "bsr" k
>>| mapM_ (const $ tell [Instr "ajs" [Lit -1] ""]) es //clean up args
- >>| pure ()
+ >>| mapM_ g fs
+ >>| pure ()
g (ReturnStmt Nothing) = tell [Instr "unlink" [] ""]
>>| tell [Instr "ret" [] ""]
g (ReturnStmt (Just e)) = g e
instance g FunDecl where
g (FunDecl _ k args _ vds stms) =
//varDecls can call the enclosing function, so first reserve a label for it
- updateAdressbook (extend k (LAB k)) >>|
+ updateAdressbook (extend k (LAB k (length args))) >>|
getAdressbook >>= \oldMap ->
updateAdressbook (addVars args) >>|
tell [Lab k] >>|