{-# LANGUAGE OverloadedStrings #-}
+{-# LANGUAGE RecursiveDo #-}
module Main where
import qualified AST
+import Control.Monad
+import Control.Monad.Trans.Class
+import qualified Data.Map as Map
import qualified Data.Text.Lazy.IO as Text
+import Data.String
+import Foreign.Ptr
+import System.Exit
+import System.IO
+import LLVM.Context
+import LLVM.ExecutionEngine
+import LLVM.Module
+import LLVM.PassManager
import LLVM.IRBuilder
+import LLVM.AST.AddrSpace
import LLVM.AST.Constant
import LLVM.AST.Float
+import LLVM.AST.FloatingPointPredicate hiding (False, True)
import LLVM.AST.Operand
-import LLVM.AST.Type
+import LLVM.AST.Type as Type
+import LLVM.AST.Typed
import LLVM.Pretty
+type ModuleBuilderE = ModuleBuilderT (Either String)
+
+foreign import ccall "dynamic" exprFun :: FunPtr (IO Float) -> IO Float
+
main :: IO ()
main = do
- ast <- read <$> getContents
- let mdl = buildModule "main" $
- function "expr" [] float $ \_ -> do
- build ast
- return ()
- Text.putStrLn (ppllvm mdl)
-
-build :: AST.Expr -> IRBuilderT ModuleBuilder Operand
-build (AST.Num a) = pure $ ConstantOperand (Float (Single a))
-build (AST.Add a b) = do
- va <- build a
- vb <- build b
- fadd va vb
+ AST.Program asts <- read <$> getContents
+ let eitherMdl = buildModuleT "main" $ mapM buildAST asts
+ case eitherMdl of
+ Left err -> die err
+ Right mdl -> withContext $ \ctx -> do
+ hPutStrLn stderr "Before optimisation:"
+ Text.hPutStrLn stderr (ppllvm mdl)
+ withMCJIT ctx Nothing Nothing Nothing Nothing $ \mcjit ->
+ withModuleFromAST ctx mdl $ \mdl' ->
+ withPassManager defaultCuratedPassSetSpec $ \pm -> do
+ runPassManager pm mdl' >>= guard
+ hPutStrLn stderr "After optimisation:"
+ Text.hPutStrLn stderr . ppllvm =<< moduleAST mdl'
+ withModuleInEngine mcjit mdl' $ \emdl -> do
+ Just f <- getFunction emdl "expr"
+ let f' = castFunPtr f :: FunPtr (IO Float)
+ exprFun f' >>= print
+
+evalProg :: AST.Program -> IO (Maybe Float)
+evalProg (AST.Program asts) = do
+ let eitherMdl = buildModuleT "main" $ mapM buildAST asts
+ case eitherMdl of
+ Left _ -> return Nothing
+ Right mdl -> withContext $ \ctx ->
+ withMCJIT ctx Nothing Nothing Nothing Nothing $ \mcjit ->
+ withModuleFromAST ctx mdl $ \mdl' ->
+ withModuleInEngine mcjit mdl' $ \emdl -> do
+ Just f <- getFunction emdl "expr"
+ let f' = castFunPtr f :: FunPtr (IO Float)
+ Just <$> exprFun f'
+
+-- | Builds up programs at the top-level of an LLVM Module
+-- >>> evalProg (read "31 - 5")
+-- Just 26.0
+buildAST :: AST.AST -> ModuleBuilderE Operand
+buildAST (AST.Function nameStr paramStrs body) = do
+ let n = fromString nameStr
+ function n params float $ \binds -> do
+ let bindMap = Map.fromList (zip paramStrs binds)
+ buildExpr bindMap body >>= ret
+ where params = zip (repeat float) (map fromString paramStrs)
+buildAST (AST.Eval e) =
+ function "expr" [] float $ \_ -> buildExpr mempty e >>= ret
+
+-- | Builds up expressions, which are operands in LLVM IR
+-- >>> evalProg (read "def foo(x) x * 2; foo(6)")
+-- Just 12.0
+-- >>> evalProg (read "if 3 > 2 then 42 else 12")
+-- Just 42.0
+buildExpr :: Map.Map String Operand -> AST.Expr -> IRBuilderT ModuleBuilderE Operand
+buildExpr _ (AST.Num a) = pure $ ConstantOperand (Float (Single a))
+buildExpr binds (AST.Var n) = case binds Map.!? n of
+ Just x -> pure x
+ Nothing -> lift $ lift $ Left $ "'" <> n <> "' doesn't exist in scope"
+
+buildExpr binds (AST.Call nameStr params) = do
+ paramOps <- mapM (buildExpr binds) params
+ let name = fromString nameStr
+ -- get a pointer to the function
+ typ = FunctionType float (replicate (length params) float) False
+ ptrTyp = Type.PointerType typ (AddrSpace 0)
+ ref = GlobalReference ptrTyp name
+ call (ConstantOperand ref) (zip paramOps (repeat []))
+
+buildExpr binds (AST.BinOp op a b) = do
+ va <- buildExpr binds a
+ vb <- buildExpr binds b
+ let instr = case op of
+ AST.Add -> fadd
+ AST.Sub -> fsub
+ AST.Mul -> fmul
+ AST.Cmp GT -> fcmp OGT
+ AST.Cmp LT -> fcmp OLT
+ AST.Cmp EQ -> fcmp OEQ
+ instr va vb
+
+buildExpr binds (AST.If cond thenE elseE) = mdo
+ _ifB <- block `named` "if"
+
+ condV <- buildExpr binds cond
+ when (typeOf condV /= i1) $ lift $ lift $ Left "Not a boolean"
+ condBr condV thenB elseB
+
+ thenB <- block `named` "then"
+ thenOp <- buildExpr binds thenE
+ br mergeB
+
+ elseB <- block `named` "else"
+ elseOp <- buildExpr binds elseE
+ br mergeB
+
+ mergeB <- block `named` "ifcont"
+ phi [(thenOp, thenB), (elseOp, elseB)]