-(* L1 Compiler
+(* L3 Compiler
* AST -> IR Translator
* Author: Kaustuv Chaudhuri <kaustuv+@cs.cmu.edu>
* Modified by: Alex Vaynberg <alv@andrew.cmu.edu>
* Modified: Frank Pfenning <fp@cs.cmu.edu>
+ * Modified: Chris Lu <czl@andrew.cmu.edu>
+ * Modified: Joshua Wise <jwise@andrew.cmu.edu>
*)
signature TRANS =
sig
(* translate abstract syntax tree to IR tree *)
- val translate : Ast.program -> Tree.stm list
+ val translate : Ast.program -> Tree.func list
end
structure Trans :> TRANS =
structure A = Ast
structure T = Tree
-
+
fun trans_oper A.PLUS = T.ADD
| trans_oper A.MINUS = T.SUB
| trans_oper A.TIMES = T.MUL
| trans_oper A.DIVIDEDBY = T.DIV
| trans_oper A.MODULO = T.MOD
- | trans_oper A.NEGATIVE = T.SUB (* unary to binary! *)
-
- and trans_exp env (A.Var(id)) =
- (* after type-checking, id must be declared; do not guard lookup *)
- T.TEMP (Symbol.look' env id)
- | trans_exp env (A.ConstExp c) = T.CONST(c)
- | trans_exp env (A.OpExp(oper, [e1, e2])) =
- T.BINOP(trans_oper oper, trans_exp env e1, trans_exp env e2)
- | trans_exp env (A.OpExp(A.NEGATIVE, [e])) =
- T.BINOP(trans_oper A.NEGATIVE, T.CONST(Word32Signed.ZERO), trans_exp env e)
- | trans_exp env (A.Marked(marked_exp)) =
- trans_exp env (Mark.data marked_exp)
- (* anything else should be impossible *)
-
- (* translate the statement *)
- (* trans_stms : Temp.temp Symbol.table -> A.stm list -> Tree.stm list *)
- fun trans_stms env (A.Assign(id,e)::stms) =
- let val t = Temp.new()
- val env' = Symbol.bind env (id, t)
- in
- T.MOVE(T.TEMP(t), trans_exp env e)
- :: trans_stms env' stms
- end
- | trans_stms env (A.Return e::nil) =
- (* after type-checking, return must be last statement *)
- T.RETURN (trans_exp env e) :: nil
-
- fun translate p = trans_stms Symbol.empty p
+ | trans_oper A.LSH = T.LSH
+ | trans_oper A.RSH = T.RSH
+ | trans_oper A.LOGOR = T.LOGOR
+ | trans_oper A.LOGAND = T.LOGAND
+ | trans_oper A.BITOR = T.BITOR
+ | trans_oper A.BITXOR = T.BITXOR
+ | trans_oper A.BITAND = T.BITAND
+ | trans_oper A.NEQ = T.NEQ
+ | trans_oper A.EQ = T.EQ
+ | trans_oper A.LT = T.LT
+ | trans_oper A.LE = T.LE
+ | trans_oper A.GE = T.GE
+ | trans_oper A.GT = T.GT
+ | trans_oper _ = raise ErrorMsg.InternalError "expected AST binop, got AST unop"
+
+ fun translate p =
+ let
+ val allfuncs = foldr (fn (A.Extern(_),b) => b
+ | (A.Function(_, id, _, _, _), b) => Symbol.bind b (id, () ))
+ Symbol.empty p
+
+ fun trans_unop A.NEGATIVE = T.NEG
+ | trans_unop A.BITNOT = T.BITNOT
+ | trans_unop A.BANG = T.BANG
+ | trans_unop _ = raise ErrorMsg.InternalError "expected AST unop, got AST binop"
+
+ fun trans_exp env (A.Var(id)) =
+ (* after type-checking, id must be declared; do not guard lookup *)
+ T.TEMP (Symbol.look' env id)
+ | trans_exp env (A.ConstExp c) = T.CONST(c)
+ | trans_exp env (A.OpExp(oper, [e1, e2])) =
+ T.BINOP(trans_oper oper, trans_exp env e1, trans_exp env e2)
+ | trans_exp env (A.OpExp(oper, [e])) =
+ T.UNOP(trans_unop oper, trans_exp env e)
+ | trans_exp env (A.OpExp(oper, _)) =
+ raise ErrorMsg.InternalError "expected one or two operands, got it in the oven"
+ | trans_exp env (A.Marked(marked_exp)) =
+ trans_exp env (Mark.data marked_exp)
+ | trans_exp env (A.FuncCall(func, stms)) =
+ T.CALL(func, List.map (trans_exp env) stms)
+
+ (* anything else should be impossible *)
+
+ (* trans_stms : Temp.temp Symbol.table -> (Label.label * Label.label) option -> A.stm list -> Tree.stm list
+ * translates a statement to the corresponding IR
+ * we pass around the environment and the current loop context, if any
+ * (usually called ls, which contains a continue label and a break label)
+ *)
+ fun trans_stms vars ls (A.Assign(id,e)::stms) =
+ let
+ val t = Symbol.look' vars id handle Option => raise ErrorMsg.InternalError "Undeclared variable, should have been caught in typechecker..."
+ val remainder = trans_stms vars ls stms
+ in
+ T.MOVE(T.TEMP(t), trans_exp vars e)
+ :: remainder
+ end
+ | trans_stms vars ls (A.Return e::stms) =
+ let
+ val remainder = trans_stms vars ls stms
+ in
+ T.RETURN (trans_exp vars e)
+ :: remainder
+ end
+
+ | trans_stms vars ls (A.If(e, s, NONE)::stms) =
+ let
+ val l = Label.new ()
+ val strans = trans_stms vars ls s
+ val remainder = trans_stms vars ls stms
+ in
+ (T.JUMPIFN(trans_exp vars e, l)
+ :: strans
+ @ [T.LABEL (l)]
+ @ remainder)
+ end
+ | trans_stms vars ls (A.If(e, s, SOME s2)::stms) =
+ let
+ val l = Label.new ()
+ val l2 = Label.new ()
+ val s1trans = trans_stms vars ls s
+ val s2trans = trans_stms vars ls s2
+ val remainder = trans_stms vars ls stms
+ in
+ (T.JUMPIFN(trans_exp vars e, l)
+ :: s1trans
+ @ [T.JUMP (l2), T.LABEL (l)]
+ @ s2trans
+ @ [T.LABEL (l2)]
+ @ remainder)
+ end
+ | trans_stms vars ls (A.For(s1, e, s2, s)::stms) =
+ let
+ val head = Label.new ()
+ val tail = Label.new ()
+ val loop = Label.new ()
+ val stm1 = if isSome s1 then trans_stms vars NONE [valOf s1] else nil
+ val strans = trans_stms vars (SOME(loop,tail)) s
+ val stm2 = if isSome s2 then trans_stms vars NONE [valOf s2] else nil
+ val remainder = trans_stms vars ls stms
+ in
+ (stm1
+ @ [T.LABEL head, T.JUMPIFN(trans_exp vars e, tail)]
+ @ strans
+ @ [T.LABEL loop]
+ @ stm2
+ @ [T.JUMP head, T.LABEL tail]
+ @ remainder)
+ end
+ | trans_stms vars ls (A.While(e, s)::stms) =
+ let
+ val head = Label.new ()
+ val tail = Label.new ()
+ val strans = trans_stms vars (SOME(head,tail)) s
+ val remainder = trans_stms vars ls stms
+ in
+ (T.LABEL head
+ :: T.JUMPIFN(trans_exp vars e, tail)
+ :: strans
+ @ [T.JUMP head, T.LABEL tail]
+ @ remainder)
+ end
+
+ | trans_stms vars (SOME(b,e)) (A.Break::stms) =
+ let
+ val remainder = trans_stms vars (SOME(b,e)) stms
+ in
+ ((T.JUMP e) :: remainder)
+ end
+ | trans_stms vars NONE (A.Break::_) = raise ErrorMsg.InternalError "Break from invalid location... should have been caught in typechecker"
+ | trans_stms vars (SOME(b,e)) (A.Continue::stms) =
+ let
+ val remainder = trans_stms vars (SOME(b,e)) stms
+ in
+ ((T.JUMP b) :: remainder)
+ end
+ | trans_stms vars NONE (A.Continue::_) = raise ErrorMsg.InternalError "Continue from invalid location... should have been caught in typechecker"
+ | trans_stms vars ls (A.Nop::stms) = trans_stms vars ls stms
+ | trans_stms vars ls (A.MarkedStm m :: stms) = trans_stms vars ls ((Mark.data m) :: stms)
+ | trans_stms vars _ nil = nil
+
+ fun trans_funcs (A.Extern(t, id, varl)::l) = trans_funcs l
+ | trans_funcs (A.Function(t, id, args, vars, body)::l) =
+ let
+ val (a,_) = ListPair.unzip (args @ vars)
+ val allvars = foldr (fn (a,b) => Symbol.bind b (a, Temp.new(Symbol.name(a)))) Symbol.empty a
+ val b = trans_stms allvars NONE body
+ val (argn,_) = ListPair.unzip args
+ val numberedargs = ListPair.zip (List.tabulate (length argn, fn x => x), argn)
+ val argmv = map
+ (fn (n, argname) => T.MOVE(T.TEMP (Symbol.look' allvars argname), T.ARG n))
+ numberedargs
+ in
+ (T.FUNCTION(id, argmv @ b)) :: (trans_funcs l)
+ end
+ | trans_funcs nil = nil
+ in
+ trans_funcs p
+ end
end
git.joshuawise.com / snipe.git / blobdiff