From 37dcd45432ac7d315e0404bf3205ee80476070c3 Mon Sep 17 00:00:00 2001
From: sudoer777 <git@sudoer.ch>
Date: Sun, 17 Sep 2023 23:18:55 -0500
Subject: [PATCH] Copy and paste llvm-hs-examples/basic on GitHub to
 LLVMGen/Expression.hs and configure stack to compile it correctly

---
 README.md                            | 15 +++++---
 app/LLVMGen/Expression.hs            | 51 ++++++++++++++++++++++++++++
 package.yaml                         |  9 +++--
 really-bad-compiler-in-haskell.cabal |  7 ++--
 stack.yaml                           | 11 +++---
 stack.yaml.lock                      | 13 +++++++
 6 files changed, 92 insertions(+), 14 deletions(-)
 create mode 100644 app/LLVMGen/Expression.hs

diff --git a/README.md b/README.md
index 17550b8..f26cbc7 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,6 @@
 # Really Bad Compiler in Haskell
 
-A compiler written in Haskell that is really bad (I do not know what language I am going to compile yet). Built for the Introduction to Compiler Design class at The University of Texas at Dallas.
+A compiler written in Haskell which can currently perform basic arithmetic using the megaparsec and llvm-hs libraries (I do not know what language I am going to compile yet). Built for the Introduction to Compiler Design class at The University of Texas at Dallas.
 
 Main repo: https://git.sudoer.ch/me/really-bad-compiler-in-haskell
 
@@ -8,9 +8,15 @@ Main repo: https://git.sudoer.ch/me/really-bad-compiler-in-haskell
 
 - Install `ghcup` (for managing Haskell tools) and `nix` (for managing external dependencies).
 - Clone the repo.
-- Use `ghcup` to install `stack 2.9.3`, `HLS 2.2.0.0`, and `cabal 3.6.2.0`.
+- Use `ghcup` to install `stack 2.9.3`, `HLS 2.2.0.0`, `GHC 9.2.8`, and `cabal 3.6.2.0`.
 - Use `stack run <file>` to run the program (for example, `stack run example/1`).
 
+## Known bugs
+
+### Building
+
+- If llvm_16 is in the nix store, stack will use it for some reason and the build will fail. Currently, you may need to run `nix-store --delete /nix/store/<llvm16devdirectory>` to build it.
+
 ## File structure
 
 - `app` - contains the compiler program
@@ -25,13 +31,14 @@ Main repo: https://git.sudoer.ch/me/really-bad-compiler-in-haskell
 - https://akashagrawal.me/2017/01/19/beginners-guide-to-megaparsec.html
 - https://markkarpov.com/tutorial/megaparsec.html (for help writing a Haskell equation parser)
 - https://www.forth.com/starting-forth/1-forth-stacks-dictionary/ (for learning Forth)
-- https://blog.josephmorag.com/posts/mcc0/ (Haskell LLVM tutorial)
+- https://blog.josephmorag.com/posts/mcc0/ (Haskell compiler tutorial with megaparsec, llvm-hs, and nix)
+- https://gh.sudoer.ch/llvm-hs/llvm-hs-examples (for help writing an llvm code generator)
 
 ### Tools
 
 - Language: Haskell
 - Haskell tools: GHCup, Stack, Cabal
-- Libraries: megaparsec, parser-combinators, text, llvm-hs-pure, llvm-hs-pretty
+- Libraries: megaparsec, parser-combinators, text, llvm-hs-pure
 - Dependencies: llvm, clang
 - IDE: VSCodium
 - Git platform: Forgejo
diff --git a/app/LLVMGen/Expression.hs b/app/LLVMGen/Expression.hs
new file mode 100644
index 0000000..0b2c4d2
--- /dev/null
+++ b/app/LLVMGen/Expression.hs
@@ -0,0 +1,51 @@
+module LLVMGen.Expression () where
+
+import qualified Objects.Expression as Expr
+
+import LLVM.AST
+import qualified LLVM.AST as AST
+import LLVM.AST.Global
+import LLVM.Context
+import LLVM.Module
+
+import Data.ByteString.Char8 as BS
+
+int :: Type
+int = IntegerType 32
+
+defAdd :: Definition
+defAdd = GlobalDefinition functionDefaults
+  { name = Name "add"
+  , parameters =
+      ( [ Parameter int (Name "a") []
+        , Parameter int (Name "b") [] ]
+      , False )
+  , returnType = int
+  , basicBlocks = [body]
+  }
+  where
+    body = BasicBlock
+        (Name "entry")
+        [ Name "result" :=
+            Add False  -- no signed wrap
+                False  -- no unsigned wrap
+                (LocalReference int (Name "a"))
+                (LocalReference int (Name "b"))
+                []]
+        (Do $ Ret (Just (LocalReference int (Name "result"))) [])
+
+
+module_ :: AST.Module
+module_ = defaultModule
+  { moduleName = "basic"
+  , moduleDefinitions = [defAdd]
+  }
+
+
+toLLVM :: AST.Module -> IO ()
+toLLVM modul = withContext $ \ctx -> do
+  llvm <- withModuleFromAST ctx modul moduleLLVMAssembly
+  BS.putStrLn llvm
+
+main :: IO ()
+main = toLLVM module_
\ No newline at end of file
diff --git a/package.yaml b/package.yaml
index 80581b1..af19751 100644
--- a/package.yaml
+++ b/package.yaml
@@ -6,12 +6,14 @@ dependencies:
   - megaparsec >= 9.0.1 && < 10
   - parser-combinators
   - text
+  - llvm-hs >= 15 && < 16
   - llvm-hs-pure >= 15 && < 16
-  # - llvm-hs-pretty >= 12 && < 13
-tested-with: GHC == 8.10.7
+  # - llvm-hs-pretty >= 15 && < 16
+  - bytestring
+tested-with: GHC == 9.2.8
 category: Compilers/Interpreters
 
-ghc-options: -threaded -Wall -j8 +RTS -A64M -RTS
+ghc-options: -threaded -Wall -j8 +RTS -A64M -RTS -fllvm
 
 # library:
 #   source-dirs: src
@@ -25,3 +27,4 @@ executable:
 #     source-dirs: test
 
 default-extensions: OverloadedStrings, LambdaCase
+# flags: -fno-hs-llvm=true
diff --git a/really-bad-compiler-in-haskell.cabal b/really-bad-compiler-in-haskell.cabal
index cb9167b..25ecb34 100644
--- a/really-bad-compiler-in-haskell.cabal
+++ b/really-bad-compiler-in-haskell.cabal
@@ -11,12 +11,13 @@ author:         sudoer777
 maintainer:     sudoer777
 build-type:     Simple
 tested-with:
-    GHC == 8.10.7
+    GHC == 9.2.8
 
 executable really-bad-compiler-in-haskell
   main-is: Main.hs
   other-modules:
       Eval.Expression
+      LLVMGen.Expression
       Objects.Expression
       Parser.Expression
       Paths_really_bad_compiler_in_haskell
@@ -24,9 +25,11 @@ executable really-bad-compiler-in-haskell
       app
   default-extensions:
       OverloadedStrings, LambdaCase
-  ghc-options: -threaded -Wall -j8 +RTS -A64M -RTS
+  ghc-options: -threaded -Wall -j8 +RTS -A64M -RTS -fllvm
   build-depends:
       base >=4.14.3 && <5
+    , bytestring
+    , llvm-hs ==15.*
     , llvm-hs-pure ==15.*
     , megaparsec >=9.0.1 && <10
     , parser-combinators
diff --git a/stack.yaml b/stack.yaml
index 0d6c2e8..f5a1103 100644
--- a/stack.yaml
+++ b/stack.yaml
@@ -3,14 +3,15 @@ resolver: lts-20.26
 packages:
   - .
 extra-deps:
-  # - github: llvm-hs/llvm-hs-pretty
-  #   commit: 655ff4d47b3a584b4c9a5863f6121b954825920c
+  # - github: hyunsooda/llvm-hs-pretty-15
+  #   commit: 79283942d1667168ecd65237667aff7fed730303
   - github: llvm-hs/llvm-hs
     commit: 5bca2c1a2a3aa98ecfb19181e7a5ebbf3e212b76
     subdirs:
       - llvm-hs-pure
+      - llvm-hs
 nix:
   enable: true
-  packages: [llvm_16, clang_16]
-# system-ghc: true
-# install-ghc: false
+  packages: [llvm_15, clang_15, libxml2]
+system-ghc: true
+install-ghc: true
diff --git a/stack.yaml.lock b/stack.yaml.lock
index 6b809c3..0055e8d 100644
--- a/stack.yaml.lock
+++ b/stack.yaml.lock
@@ -17,6 +17,19 @@ packages:
   original:
     subdir: llvm-hs-pure
     url: https://github.com/llvm-hs/llvm-hs/archive/5bca2c1a2a3aa98ecfb19181e7a5ebbf3e212b76.tar.gz
+- completed:
+    name: llvm-hs
+    pantry-tree:
+      sha256: 21f74a6f51fae6c0a0fcf3e6620a59f341289ac743998b41ed3276fd1b7d8862
+      size: 12716
+    sha256: 526b67e2da9ce25b3856c221b6772e699a7593dbb5ba38e7ee2436349de70966
+    size: 9802209
+    subdir: llvm-hs
+    url: https://github.com/llvm-hs/llvm-hs/archive/5bca2c1a2a3aa98ecfb19181e7a5ebbf3e212b76.tar.gz
+    version: 15.0.0
+  original:
+    subdir: llvm-hs
+    url: https://github.com/llvm-hs/llvm-hs/archive/5bca2c1a2a3aa98ecfb19181e7a5ebbf3e212b76.tar.gz
 snapshots:
 - completed:
     sha256: 5a59b2a405b3aba3c00188453be172b85893cab8ebc352b1ef58b0eae5d248a2