+import System.IO.Error
+import Text.Read (readMaybe)
+
+main :: IO ()
+main = buildModuleT "main" repl >>= Text.hPutStrLn stderr . ("\n" <>) . ppll
+
+repl :: ModuleBuilderT IO ()
+repl = do
+ liftIO $ hPutStr stderr "ready> "
+ mline <- liftIO $ catchIOError (Just <$> getLine) eofHandler
+ case mline of
+ Nothing -> return ()
+ Just l -> do
+ case readMaybe l of
+ Nothing -> liftIO $ hPutStrLn stderr "Couldn't parse"
+ Just ast -> do
+ hoist $ buildAST ast
+ mostRecentDef >>= liftIO . Text.hPutStrLn stderr . ppll
+ repl
+ where
+ eofHandler e
+ | isEOFError e = return Nothing
+ | otherwise = ioError e
+
+type Binds = Map.Map String Operand
+
+buildAST :: AST -> ModuleBuilder Operand
+buildAST (Function (Prototype nameStr paramStrs) body) = do
+ let n = fromString nameStr
+ function n params Type.double $ \ops -> do
+ let binds = Map.fromList (zip paramStrs ops)
+ flip runReaderT binds $ buildExpr body >>= ret
+ where params = zip (repeat Type.double) (map fromString paramStrs)
+
+buildAST (Extern (Prototype nameStr params)) =
+ extern (fromString nameStr) (replicate (length params) Type.double) Type.double
+
+buildAST (TopLevelExpr x) = function "__anon_expr" [] Type.double $
+ const $ flip runReaderT mempty $ buildExpr x >>= ret
+
+buildExpr :: Expr -> ReaderT Binds (IRBuilderT ModuleBuilder) Operand
+buildExpr (Num x) = pure $ ConstantOperand (Float (Double x))
+buildExpr (Var n) = do
+ binds <- ask
+ case binds Map.!? n of
+ Just x -> pure x
+ Nothing -> error $ "'" <> n <> "' doesn't exist in scope"
+
+buildExpr (BinOp op a b) = do
+ opA <- buildExpr a
+ opB <- buildExpr b
+ tmp <- instr opA opB
+ if isCmp
+ then uitofp tmp Type.double
+ else return tmp
+ where isCmp
+ | Cmp _ <- op = True
+ | otherwise = False
+ instr = case op of
+ K.Add -> fadd
+ K.Sub -> fsub
+ K.Mul -> fmul
+ K.Cmp LT -> fcmp OLT
+ K.Cmp GT -> fcmp OGT
+ K.Cmp EQ -> fcmp OEQ
+
+buildExpr (Call callee params) = do
+ paramOps <- mapM buildExpr params
+ let nam = fromString callee
+ -- get a pointer to the function
+ typ = FunctionType Type.double (replicate (length params) Type.double) False
+ ptrTyp = Type.PointerType typ (AddrSpace 0)
+ ref = GlobalReference ptrTyp nam
+ call (ConstantOperand ref) (zip paramOps (repeat []))