Add stage options

5 files changed, 133 insertions, 70 deletions

diff --git a/elna.cabal b/elna.cabal
index 8b79dbe..d591206 100644
--- a/elna.cabal
+++ b/elna.cabal
@@ -16,6 +16,7 @@ common warnings
     build-depends:
         base >=4.7 && <5,
         bytestring ^>= 0.12.1,
+        filepath ^>= 1.5.3,
         megaparsec ^>= 9.6,
         optparse-applicative ^>= 0.18.1,
         vector ^>= 0.13.1,
@@ -36,7 +37,8 @@ library elna-internal
         Language.Elna.Architecture.RiscV
         Language.Elna.Backend.Allocator
         Language.Elna.Backend.Intermediate
-        Language.Elna.CommandLine
+        Language.Elna.Driver
+        Language.Elna.Driver.CommandLine
         Language.Elna.Frontend.AST
         Language.Elna.Frontend.NameAnalysis
         Language.Elna.Frontend.Parser
@@ -62,8 +64,7 @@ executable elna
     import: warnings
     main-is: Main.hs
     build-depends:
-        elna:elna-internal,
-        filepath ^>= 1.5.3
+        elna:elna-internal
     hs-source-dirs: src
 
 test-suite elna-test
diff --git a/lib/Language/Elna/CommandLine.hs b/lib/Language/Elna/CommandLine.hs
deleted file mode 100644
index 19898e2..0000000
--- a/lib/Language/Elna/CommandLine.hs
+++ /dev/null
@@ -1,48 +0,0 @@
-{- This Source Code Form is subject to the terms of the Mozilla Public License,
-   v. 2.0. If a copy of the MPL was not distributed with this file, You can
-   obtain one at https://mozilla.org/MPL/2.0/. -}
-
-module Language.Elna.CommandLine
-    ( CommandLine(..)
-    , commandLine
-    , execParser
-    ) where
-
-import Options.Applicative
-    ( Parser
-    , ParserInfo(..)
-    , argument
-    , execParser
-    , fullDesc
-    , help
-    , helper
-    , info
-    , long
-    , metavar
-    , optional
-    , progDesc
-    , short
-    , str
-    , strOption
-    )
-import Control.Applicative ((<**>))
-
-data CommandLine = CommandLine
-    { input :: FilePath
-    , output :: Maybe FilePath
-    } deriving (Eq, Show)
-
-parser :: Parser CommandLine
-parser = CommandLine
-    <$> argument str inFile
-    <*> optional (strOption outFile)
-  where
-    inFile = metavar "INFILE" <> help "Input file."
-    outFile = long "output"
-        <> short 'o'
-        <> metavar "OUTFILE"
-        <> help "Output file."
-
-commandLine :: ParserInfo CommandLine
-commandLine = info (parser <**> helper)
-    $ fullDesc <> progDesc "Elna compiler."
diff --git a/lib/Language/Elna/Driver.hs b/lib/Language/Elna/Driver.hs
new file mode 100644
index 0000000..9d13f59
--- /dev/null
+++ b/lib/Language/Elna/Driver.hs
@@ -0,0 +1,37 @@
+{- This Source Code Form is subject to the terms of the Mozilla Public License,
+   v. 2.0. If a copy of the MPL was not distributed with this file, You can
+   obtain one at https://mozilla.org/MPL/2.0/. -}
+
+module Language.Elna.Driver
+    ( Driver(..)
+    , IntermediateStage(..)
+    , drive
+    , execParser
+    ) where
+
+import Data.Maybe (fromMaybe)
+import Language.Elna.Driver.CommandLine
+    ( CommandLine(..)
+    , IntermediateStage(..)
+    , commandLine
+    )
+import Options.Applicative (execParser)
+import System.FilePath (replaceExtension, takeFileName)
+
+data Driver = Driver
+    { input :: FilePath
+    , output :: FilePath
+    , intermediateStage :: Maybe IntermediateStage
+    } deriving (Eq, Show)
+
+drive :: IO Driver
+drive = rewrite <$> execParser commandLine
+  where
+    rewrite CommandLine{..} =
+        let defaultOutputName = replaceExtension (takeFileName input) "o"
+            outputName = fromMaybe defaultOutputName output
+         in Driver
+            { input = input
+            , output = outputName
+            , intermediateStage = intermediateStage
+            }
diff --git a/lib/Language/Elna/Driver/CommandLine.hs b/lib/Language/Elna/Driver/CommandLine.hs
new file mode 100644
index 0000000..1bd5f14
--- /dev/null
+++ b/lib/Language/Elna/Driver/CommandLine.hs
@@ -0,0 +1,69 @@
+{- This Source Code Form is subject to the terms of the Mozilla Public License,
+   v. 2.0. If a copy of the MPL was not distributed with this file, You can
+   obtain one at https://mozilla.org/MPL/2.0/. -}
+
+module Language.Elna.Driver.CommandLine
+    ( CommandLine(..)
+    , IntermediateStage(..)
+    , commandLine
+    ) where
+
+import Options.Applicative
+    ( Parser
+    , ParserInfo(..)
+    , argument
+    , flag'
+    , fullDesc
+    , help
+    , helper
+    , info
+    , long
+    , metavar
+    , optional
+    , progDesc
+    , short
+    , str
+    , strOption
+    )
+import Control.Applicative (Alternative(..), (<**>))
+
+data IntermediateStage
+    = ParseStage
+    | ValidateStage
+    | CodeGenStage
+    deriving (Eq, Show)
+
+data CommandLine = CommandLine
+    { input :: FilePath
+    , output :: Maybe FilePath
+    , intermediateStage :: Maybe IntermediateStage
+    } deriving (Eq, Show)
+
+intermediateStageP :: Parser IntermediateStage
+intermediateStageP
+    = flag' ParseStage parseStageP
+    <|>  flag' ValidateStage validateStageP
+    <|> flag' CodeGenStage codeGenStageP
+  where
+    parseStageP = long "parse"
+        <> help "Run the lexer and parser, but stop before assembly generation"
+    validateStageP = long "validate"
+        <> help "Run through the semantic analysis stage, stopping before TAC generation"
+    codeGenStageP = long "codegen"
+        <> help "Perform lexing, parsing, and assembly generation, but stop before code emission"
+
+commandLineP :: Parser CommandLine
+commandLineP = CommandLine
+    <$> argument str inFile
+    <*> optional (strOption outFile)
+    <*> optional intermediateStageP
+  where
+    inFile = metavar "INFILE" <> help "Input file."
+    outFile = long "output"
+        <> short 'o'
+        <> metavar "OUTFILE"
+        <> help "Output file."
+
+commandLine :: ParserInfo CommandLine
+commandLine = info (commandLineP <**> helper)
+    $ fullDesc <> progDesc "Elna compiler."
diff --git a/src/Main.hs b/src/Main.hs
index aff5360..9e70cd6 100644
--- a/src/Main.hs
+++ b/src/Main.hs
@@ -6,7 +6,11 @@ module Main
     ( main
     ) where
 
-import Language.Elna.CommandLine (CommandLine(..), commandLine, execParser)
+import Language.Elna.Driver
+    ( Driver(..)
+    , IntermediateStage(..)
+    , drive
+    )
 import Language.Elna.Object.ElfCoder (elfObject)
 import Language.Elna.Backend.Allocator (allocate)
 import Language.Elna.Glue (glue)
@@ -15,8 +19,6 @@ import Language.Elna.Frontend.Parser (programP)
 import Language.Elna.Frontend.TypeAnalysis (typeAnalysis)
 import Language.Elna.RiscV.CodeGenerator (generateRiscV, riscVConfiguration)
 import Language.Elna.RiscV.ElfWriter (riscv32Elf)
-import Data.Maybe (fromMaybe)
-import System.FilePath (replaceExtension, takeFileName)
 import Text.Megaparsec (runParser, errorBundlePretty)
 import qualified Data.Text.IO as Text
 import System.Exit (ExitCode(..), exitWith)
@@ -32,27 +34,29 @@ import Control.Exception (IOException, catch)
 -- 6 - Register allocation error.
 
 main :: IO ()
-main = execParser commandLine >>= withCommandLine
+main = drive >>= withCommandLine
   where
-    withCommandLine CommandLine{..} =
-        let defaultOutputName = replaceExtension (takeFileName input) "o"
-            outputName = fromMaybe defaultOutputName output
-         in catch (Text.readFile input) (printAndExit 2 :: IOException -> IO a)
-            >>= withParsedInput outputName
-            . runParser programP input
-    withParsedInput output (Right program)
-        = either (printAndExit 4) (withSymbolTable output program)
-        $ nameAnalysis program
+    withCommandLine driver@Driver{ input }
+        = catch (Text.readFile input) (printAndExit 2 :: IOException -> IO a)
+        >>= withParsedInput driver
+        . runParser programP input
+    withParsedInput driver@Driver{ intermediateStage } (Right program)
+        | Just ParseStage <- intermediateStage = pure ()
+        | otherwise
+            = either (printAndExit 4) (withSymbolTable driver program)
+            $ nameAnalysis program 
     withParsedInput _ (Left errorBundle)
         = putStrLn (errorBundlePretty errorBundle)
         >> exitWith (ExitFailure 3)
-    withSymbolTable output program symbolTable
+    withSymbolTable driver@Driver{ intermediateStage } program symbolTable
         | Just typeError <- typeAnalysis symbolTable program =
             printAndExit 5 typeError
-        | otherwise =
-            let makeObject = elfObject output . riscv32Elf . generateRiscV
-             in either (printAndExit 6) makeObject
-                $ allocate riscVConfiguration symbolTable
-                $ glue symbolTable program
+        | Just ValidateStage <- intermediateStage = pure ()
+        | otherwise = either (printAndExit 6) (withTac driver)
+            $ allocate riscVConfiguration symbolTable
+            $ glue symbolTable program
+    withTac Driver{ intermediateStage, output } tac
+        | Just CodeGenStage <- intermediateStage = pure ()
+        | otherwise = elfObject output $ riscv32Elf $ generateRiscV tac
     printAndExit :: Show b => forall a. Int -> b -> IO a
     printAndExit failureCode e = print e >> exitWith (ExitFailure failureCode)