RiscV-Formal/hs/Read.hs
2025-03-10 17:22:51 -04:00

66 lines
2.6 KiB
Haskell

{-# LANGUAGE DataKinds #-}
{-# LANGUAGE NumericUnderscores #-}
module Read(Read.read) where
import DecodeTypes(
Opcode(..),
RTypeFields(..), ITypeFields(..), STypeFields(..),
BTypeFields(..), UTypeFields(..), JTypeFields(..),
)
import Clash.Prelude
import Decode(DecodeResult(..))
import Cpu(RISCVCPU(..))
import RegFiles (RegVal(..), GPR)
read :: DecodeResult -> RISCVCPU -> DecodeResult
read (Opcode opc) riscvCPU =
case opc of
ADD fields -> Opcode (ADD (readRTypeFields fields (gpr riscvCPU)))
SUB fields -> Opcode (SUB (readRTypeFields fields (gpr riscvCPU)))
XOR fields -> Opcode (XOR (readRTypeFields fields (gpr riscvCPU)))
OR fields -> Opcode (OR (readRTypeFields fields (gpr riscvCPU)))
AND fields -> Opcode (AND (readRTypeFields fields (gpr riscvCPU)))
SLL fields -> Opcode (SLL (readRTypeFields fields (gpr riscvCPU)))
SRL fields -> Opcode (SRL (readRTypeFields fields (gpr riscvCPU)))
SRA fields -> Opcode (SRA (readRTypeFields fields (gpr riscvCPU)))
SLT fields -> Opcode (SLT (readRTypeFields fields (gpr riscvCPU)))
SLTU fields -> Opcode (SLTU (readRTypeFields fields (gpr riscvCPU)))
_ -> undefined
read (DecodeException e) _ = DecodeException e
read (InstructionException e) _ = InstructionException e
readRTypeFields :: RTypeFields -> GPR -> RTypeFields
readRTypeFields (RTypeFields rd funct3 rs1 rs2 funct7) gprRegFile =
let rs1_val = fetchRegVal rs1 gprRegFile
rs2_val = fetchRegVal rs2 gprRegFile
in RTypeFields rd funct3 rs1_val rs2_val funct7
readITypeFields :: ITypeFields -> GPR -> ITypeFields
readITypeFields (ITypeFields rd funct3 rs1 imm) gpr =
let rs1_val = fetchRegVal rs1 gpr
in ITypeFields rd funct3 rs1_val imm
readSTypeFields :: STypeFields -> GPR -> STypeFields
readSTypeFields (STypeFields funct3 rs1 rs2 imm12) gpr =
let rs1_val = fetchRegVal rs1 gpr
rs2_val = fetchRegVal rs2 gpr
in STypeFields funct3 rs1_val rs2_val imm12
readBTypeFields :: BTypeFields -> GPR -> BTypeFields
readBTypeFields (BTypeFields funct3 rs1 rs2 imm13) gpr =
let rs1_val = fetchRegVal rs1 gpr
rs2_val = fetchRegVal rs2 gpr
in BTypeFields funct3 rs1_val rs2_val imm13
readUTypeFields :: UTypeFields -> GPR -> UTypeFields
readUTypeFields fields@(UTypeFields rd imm20) _ = fields
readJTypeFields :: JTypeFields -> GPR -> JTypeFields
readJTypeFields fields@(JTypeFields rd imm21) _ = fields
-- Helper function to fetch register value
fetchRegVal :: RegVal -> GPR -> RegVal
fetchRegVal (Unpopulated idx) gprVal = Value idx (gprVal !! idx)
fetchRegVal val@(Value _ _) _ = val -- Already populated, no change