From: Luke Lau <luke_lau@icloud.com>
Date: Sun, 19 May 2019 13:23:31 +0000 (+0100)
Subject: Generate code for call expressions
X-Git-Url: http://git.lukelau.me/?p=kaleidoscope-hs.git;a=commitdiff_plain;h=795fc872e603cc359ec6e307969ac925c3b5dc4d

Generate code for call expressions

In order to call a function in LLVM IR, we need to grab a
GlobalReference to it. Currently we just make it ourselves, inferring
the type of it based on what arguments the caller provided and the fact
that all functions return a double.
---

diff --git a/Main.hs b/Main.hs
index f32003b..2a5a7e0 100644
--- a/Main.hs
+++ b/Main.hs
@@ -7,6 +7,7 @@ import Control.Monad.IO.Class
 import Data.String
 import qualified Data.Map as Map
 import qualified Data.Text.Lazy.IO as Text
+import LLVM.AST.AddrSpace
 import LLVM.AST.Constant
 import LLVM.AST.Float
 import LLVM.AST.FloatingPointPredicate hiding (False, True)
@@ -80,3 +81,12 @@ buildExpr (BinOp op a b) = do
                   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 []))