From: Luke Lau <luke_lau@icloud.com>
Date: Sun, 10 Mar 2019 16:07:39 +0000 (+0000)
Subject: Implement codegen for if statements
X-Git-Url: https://git.lukelau.me/?p=kaleidoscope-hs-old.git;a=commitdiff_plain;h=93653d435fe06ccc03a4b63bff1c86afba6e1ca0

Implement codegen for if statements
---

diff --git a/Main.hs b/Main.hs
index 29592b1..89fd91a 100644
--- a/Main.hs
+++ b/Main.hs
@@ -1,14 +1,17 @@
 {-# 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.IO
 import System.Exit
+import System.IO
 import LLVM.Context
 import LLVM.ExecutionEngine
 import LLVM.Module
@@ -17,11 +20,12 @@ 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 as Type
 import LLVM.Pretty
-import           Control.Monad
-import           Control.Monad.Trans.Class
+
+import Debug.Trace
 
 type ModuleBuilderE = ModuleBuilderT (Either String)
 
@@ -33,11 +37,14 @@ main = do
   let eitherMdl = buildModuleT "main" $ mapM buildAST asts
   case eitherMdl of
     Left err -> die err
-    Right mdl -> withContext $ \ctx ->
+    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"
@@ -76,4 +83,23 @@ buildExpr binds (AST.BinOp op a b) = do
                 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
+  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"
+  traceShowId <$> phi [(thenOp, thenB), (elseOp, elseB)]