3 files changed, 381 insertions, 22 deletions
diff --git a/lib/Language/Elna/Architecture/RiscV.hs b/lib/Language/Elna/Architecture/RiscV.hs
new file mode 100644
index 0000000..5d8c247
--- /dev/null
+++ b/lib/Language/Elna/Architecture/RiscV.hs
@@ -0,0 +1,286 @@
+module Language.Elna.Architecture.RiscV
+    ( BaseOpcode(..)
+    , Funct3(..)
+    , Funct7(..)
+    , Funct12(..)
+    , Instruction(..)
+    , Type(..)
+    , XRegister(..)
+    , baseOpcode
+    , funct3
+    , funct12
+    , instruction
+    , xRegister
+    ) where
+
+import qualified Data.ByteString.Builder as ByteString.Builder
+import Data.Bits (Bits(..))
+import Data.Word (Word8, Word32)
+
+data XRegister
+    = Zero
+    | RA
+    | SP
+    | GP
+    | TP
+    | T0
+    | T1
+    | T2
+    | S0
+    | S1
+    | A0
+    | A1
+    | A2
+    | A3
+    | A4
+    | A5
+    | A6
+    | A7
+    | S2
+    | S3
+    | S4
+    | S5
+    | S6
+    | S7
+    | S8
+    | S9
+    | S10
+    | S11
+    | T3
+    | T4
+    | T5
+    | T6
+    deriving Eq
+
+data Funct3
+    = ADDI
+    | SLTI
+    | SLTIU
+    | ANDI
+    | ORI
+    | XORI
+    | SLLI
+    | SRLI
+    | SRAI
+    | ADD
+    | SLT
+    | SLTU
+    | AND
+    | OR
+    | XOR
+    | SLL
+    | SRL
+    | SUB
+    | SRA
+    | BEQ
+    | BNE
+    | BLT
+    | BLTU
+    | BGE
+    | BGEU
+    | FENCE
+    | FENCEI
+    | CSRRW
+    | CSRRS
+    | CSRRC
+    | CSRRWI
+    | CSRRSI
+    | CSRRCI
+    | PRIV
+    | SB
+    | SH
+    | SW
+    | LB
+    | LH
+    | LW
+    | LBU
+    | LHU
+    | JALR
+    | MUL
+    | MULH
+    | MULHSU
+    | MULHU
+    | DIV
+    | DIVU
+    | REM
+    | REMU
+    deriving Eq
+
+data Funct12
+    = ECALL
+    | EBREAK
+    deriving Eq
+
+newtype Funct7 = Funct7
+    { funct7 :: Word8
+    } deriving Eq
+
+data BaseOpcode
+    = OpImm
+    | Lui
+    | Auipc
+    | Op
+    | Jal
+    | Jalr
+    | Branch
+    | Load
+    | Store
+    | MiscMem
+    | System
+    deriving Eq
+
+data Type
+    = I XRegister Funct3 XRegister Word32
+    | S Word32 Funct3 XRegister XRegister
+    | B Word32 Funct3 XRegister XRegister
+    | R XRegister Funct3 XRegister XRegister Funct7
+    | U XRegister Word32
+    | J XRegister Word32
+
+data Instruction = Instruction BaseOpcode Type
+
+xRegister :: XRegister -> Word8
+xRegister Zero = 0
+xRegister RA = 1
+xRegister SP = 2
+xRegister GP = 3
+xRegister TP = 4
+xRegister T0 = 5
+xRegister T1 = 6
+xRegister T2 = 7
+xRegister S0 = 8
+xRegister S1 = 9
+xRegister A0 = 10
+xRegister A1 = 11
+xRegister A2 = 12
+xRegister A3 = 13
+xRegister A4 = 14
+xRegister A5 = 15
+xRegister A6 = 16
+xRegister A7 = 17
+xRegister S2 = 18
+xRegister S3 = 19
+xRegister S4 = 20
+xRegister S5 = 21
+xRegister S6 = 22
+xRegister S7 = 23
+xRegister S8 = 24
+xRegister S9 = 25
+xRegister S10 = 26
+xRegister S11 = 27
+xRegister T3 = 28
+xRegister T4 = 29
+xRegister T5 = 30
+xRegister T6 = 31
+
+funct3 :: Funct3 -> Word8
+funct3 ADDI = 0b000
+funct3 SLTI = 0b001
+funct3 SLTIU = 0b011
+funct3 ANDI = 0b111
+funct3 ORI = 0b110
+funct3 XORI = 0b100
+funct3 SLLI = 0b000
+funct3 SRLI = 0b101
+funct3 SRAI = 0b101
+funct3 ADD = 0b000
+funct3 SLT = 0b010
+funct3 SLTU = 0b011
+funct3 AND = 0b111
+funct3 OR = 0b110
+funct3 XOR = 0b100
+funct3 SLL = 0b001
+funct3 SRL = 0b101
+funct3 SUB = 0b000
+funct3 SRA = 0b101
+funct3 BEQ = 0b000
+funct3 BNE = 0b001
+funct3 BLT = 0b100
+funct3 BLTU = 0b110
+funct3 BGE = 0b101
+funct3 BGEU = 0b111
+funct3 FENCE = 0b000
+funct3 FENCEI = 0b001
+funct3 CSRRW = 0b001
+funct3 CSRRS = 0b010
+funct3 CSRRC = 0b011
+funct3 CSRRWI = 0b101
+funct3 CSRRSI = 0b110
+funct3 CSRRCI = 0b111
+funct3 PRIV = 0b000
+funct3 SB = 0b000
+funct3 SH = 0b001
+funct3 SW = 0b010
+funct3 LB = 0b000
+funct3 LH = 0b001
+funct3 LW = 0b010
+funct3 LBU = 0b100
+funct3 LHU = 0b101
+funct3 JALR = 0b000
+funct3 MUL = 0b000
+funct3 MULH = 0b001
+funct3 MULHSU = 0b010
+funct3 MULHU = 0b011
+funct3 DIV = 0b100
+funct3 DIVU = 0b101
+funct3 REM = 0b110
+funct3 REMU = 0b111
+
+funct12 :: Funct12 -> Word8
+funct12 ECALL = 0b000000000000
+funct12 EBREAK = 0b000000000001
+
+baseOpcode :: BaseOpcode -> Word8
+baseOpcode OpImm = 0b0010011
+baseOpcode Lui = 0b0110111
+baseOpcode Auipc = 0b0010111
+baseOpcode Op = 0b0110011
+baseOpcode Jal = 0b1101111
+baseOpcode Jalr = 0b1100111
+baseOpcode Branch = 0b1100011
+baseOpcode Load = 0b0000011
+baseOpcode Store = 0b0100011
+baseOpcode MiscMem = 0b0001111
+baseOpcode System = 0b1110011
+
+type' :: Type -> Word32
+type' (I rd funct3' rs1 immediate)
+    = (fromIntegral (xRegister rd) `shiftL` 7)
+    .|. (fromIntegral (funct3 funct3') `shiftL` 12)
+    .|. (fromIntegral (xRegister rs1) `shiftL` 15)
+    .|. (immediate `shiftL` 20);
+type' (S immediate funct3' rs1 rs2)
+    = ((immediate .&. 0x1f) `shiftL` 7)
+    .|. (fromIntegral (funct3 funct3') `shiftL` 12)
+    .|. (fromIntegral (xRegister rs1) `shiftL` 15)
+    .|. (fromIntegral (xRegister rs2) `shiftL` 20)
+    .|. ((immediate .&. 0xfe0) `shiftL` 20)
+type' (B immediate funct3' rs1 rs2)
+    = ((immediate .&. 0x800) `shiftR` 4)
+    .|. ((immediate .&. 0x1e) `shiftL` 7)
+    .|. (fromIntegral (funct3 funct3') `shiftL` 12)
+    .|. (fromIntegral (xRegister rs1) `shiftL` 15)
+    .|. (fromIntegral (xRegister rs2) `shiftL` 20)
+    .|. ((immediate .&. 0x7e0) `shiftL` 20)
+    .|. ((immediate .&. 0x1000) `shiftL` 19)
+type' (R rd funct3' rs1 rs2 funct7')
+    = (fromIntegral (xRegister rd) `shiftL` 7)
+    .|. (fromIntegral (funct3 funct3') `shiftL` 12)
+    .|. (fromIntegral (xRegister rs1) `shiftL` 15)
+    .|. (fromIntegral (xRegister rs2) `shiftL` 20)
+    .|. (fromIntegral (funct7 funct7') `shiftL` 25);
+type' (U rd immediate)
+    = (fromIntegral (xRegister rd) `shiftL` 7)
+    .|. (immediate `shiftL` 12)
+type' (J rd immediate)
+     = (fromIntegral (xRegister rd) `shiftL` 7)
+     .|. (immediate .&. 0xff000)
+     .|. ((immediate .&. 0x800) `shiftL` 9)
+     .|. ((immediate .&. 0x7fe) `shiftL` 20)
+     .|. ((immediate .&. 0x100000) `shiftL` 11);
+
+instruction :: Instruction -> ByteString.Builder.Builder
+instruction (Instruction base instructionType)
+    = ByteString.Builder.word32LE
+    $ fromIntegral (baseOpcode base)
+    .|. type' instructionType
diff --git a/lib/Language/Elna/CommandLine.hs b/lib/Language/Elna/CommandLine.hs
new file mode 100644
index 0000000..b23be7d
--- /dev/null
+++ b/lib/Language/Elna/CommandLine.hs
@@ -0,0 +1,44 @@
+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/Object/Elf.hs b/lib/Language/Elna/Object/Elf.hs
index 1a4bcc8..4328f56 100644
--- a/lib/Language/Elna/Object/Elf.hs
+++ b/lib/Language/Elna/Object/Elf.hs
@@ -30,17 +30,23 @@ module Language.Elna.Object.Elf
     , elf32Rel
     , elf32Rela
     , elf32Sym
+    , elfHeaderSize
     , elfIdentification
+    , elfObject
     , rInfo
     , stInfo
     ) where
 
-import Control.Exception (Exception(..))
+import Control.Exception (Exception(..), throwIO)
 import Data.Bits (Bits(..))
 import qualified Data.ByteString.Builder as ByteString.Builder
 import Data.Int (Int32)
 import Data.Word (Word8, Word16, Word32)
 import qualified Data.ByteString as ByteString
+import Data.Vector (Vector)
+import qualified Data.Vector as Vector
+import System.IO (Handle, IOMode(..), SeekMode(..), hSeek, withFile)
+import Data.Foldable (traverse_)
 
 -- * Data types.
 
@@ -345,27 +351,6 @@ instance Enum ElfSectionType
     fromEnum SHT_HIUSER = 0xffffffff
     fromEnum (ElfSectionType x) = fromIntegral x
 
--- * Help types and functions.
-
-data ByteOrder = LSB | MSB
-    deriving Eq
-
-data ElfEncodingError
-    = ElfInvalidByteOrderError
-    | ElfUnsupportedClassError ElfClass
-    deriving Eq
-
-instance Show ElfEncodingError
-  where
-    show ElfInvalidByteOrderError = "Invalid byte order."
-    show (ElfUnsupportedClassError class') =
-        concat ["Elf class \"", show class', "\" is not supported."]
-
-instance Exception ElfEncodingError
-
-fromIntegralEnum :: (Enum a, Num b) => a -> b
-fromIntegralEnum = fromIntegral . fromEnum
-
 -- * Encoding functions.
 
 elf32Addr :: ByteOrder -> Elf32_Addr -> ByteString.Builder.Builder
@@ -462,3 +447,47 @@ stInfo binding type' = fromIntegralEnum binding `shiftL` 4
 rInfo :: Elf32_Word -> Word8 -> Elf32_Word
 rInfo symbol type' = symbol `shiftL` 8
     .|. fromIntegralEnum type'
+
+-- * Help types and functions.
+
+data ByteOrder = LSB | MSB
+    deriving Eq
+
+data ElfEncodingError
+    = ElfInvalidByteOrderError
+    | ElfUnsupportedClassError ElfClass
+    deriving Eq
+
+instance Show ElfEncodingError
+  where
+    show ElfInvalidByteOrderError = "Invalid byte order."
+    show (ElfUnsupportedClassError class') =
+        concat ["Elf class \"", show class', "\" is not supported."]
+
+instance Exception ElfEncodingError
+
+fromIntegralEnum :: (Enum a, Num b) => a -> b
+fromIntegralEnum = fromIntegral . fromEnum
+
+elfHeaderSize :: Elf32_Off
+elfHeaderSize = 52
+
+-- Writes an ELF object with the given header to the provided file path.
+-- The callback writes the sections and returns headers for those sections.
+elfObject :: FilePath -> Elf32_Ehdr -> (Handle -> IO (Vector Elf32_Shdr)) -> IO ()
+elfObject outFile header putContents = withFile outFile WriteMode withObjectFile
+  where
+    withObjectFile objectHandle
+        = hSeek objectHandle AbsoluteSeek (fromIntegral elfHeaderSize)
+        >> putContents objectHandle
+        >>= afterContents objectHandle
+    afterContents objectHandle headers =
+        let headerEncodingResult = elf32Ehdr
+                $ header
+                    { e_shoff = elfHeaderSize + Vector.foldr ((+) . sh_size) 0 headers
+                    }
+         in traverse_ (ByteString.Builder.hPutBuilder objectHandle . elf32Shdr LSB) headers
+            >> either throwIO (putHeaders objectHandle) headerEncodingResult
+    putHeaders objectHandle encodedHeader
+        = hSeek objectHandle AbsoluteSeek 0
+        >> ByteString.Builder.hPutBuilder objectHandle encodedHeader