RiscV-Formal/hs/Read.hs
2025-03-10 17:46:06 -04:00

105 lines
4.7 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 =
let gprRegFile = gpr riscvCPU
in case opc of
-- R-Type
ADD fields -> Opcode (ADD (readRTypeFields fields gprRegFile))
SUB fields -> Opcode (SUB (readRTypeFields fields gprRegFile))
XOR fields -> Opcode (XOR (readRTypeFields fields gprRegFile))
OR fields -> Opcode (OR (readRTypeFields fields gprRegFile))
AND fields -> Opcode (AND (readRTypeFields fields gprRegFile))
SLL fields -> Opcode (SLL (readRTypeFields fields gprRegFile))
SRL fields -> Opcode (SRL (readRTypeFields fields gprRegFile))
SRA fields -> Opcode (SRA (readRTypeFields fields gprRegFile))
SLT fields -> Opcode (SLT (readRTypeFields fields gprRegFile))
SLTU fields -> Opcode (SLTU (readRTypeFields fields gprRegFile))
-- I-Type
ADDI fields -> Opcode (ADDI (readITypeFields fields gprRegFile))
XORI fields -> Opcode (XORI (readITypeFields fields gprRegFile))
ORI fields -> Opcode (ORI (readITypeFields fields gprRegFile))
ANDI fields -> Opcode (ANDI (readITypeFields fields gprRegFile))
SLLI fields -> Opcode (SLLI (readITypeFields fields gprRegFile))
SRLI fields -> Opcode (SRLI (readITypeFields fields gprRegFile))
SRAI fields -> Opcode (SRAI (readITypeFields fields gprRegFile))
SLTI fields -> Opcode (SLTI (readITypeFields fields gprRegFile))
SLTIU fields -> Opcode (SLTIU (readITypeFields fields gprRegFile))
LB fields -> Opcode (LB (readITypeFields fields gprRegFile))
LH fields -> Opcode (LH (readITypeFields fields gprRegFile))
LW fields -> Opcode (LW (readITypeFields fields gprRegFile))
LBU fields -> Opcode (LBU (readITypeFields fields gprRegFile))
LHU fields -> Opcode (LHU (readITypeFields fields gprRegFile))
JALR fields -> Opcode (JALR (readITypeFields fields gprRegFile))
ECALL fields -> Opcode (ECALL (readITypeFields fields gprRegFile)) -- No regs needed, but consistent
EBREAK fields -> Opcode (EBREAK (readITypeFields fields gprRegFile)) -- Ditto
-- S-Type
SB fields -> Opcode (SB (readSTypeFields fields gprRegFile))
SH fields -> Opcode (SH (readSTypeFields fields gprRegFile))
SW fields -> Opcode (SW (readSTypeFields fields gprRegFile))
-- B-Type
BEQ fields -> Opcode (BEQ (readBTypeFields fields gprRegFile))
BNE fields -> Opcode (BNE (readBTypeFields fields gprRegFile))
BLT fields -> Opcode (BLT (readBTypeFields fields gprRegFile))
BGE fields -> Opcode (BGE (readBTypeFields fields gprRegFile))
BLTU fields -> Opcode (BLTU (readBTypeFields fields gprRegFile))
BGEU fields -> Opcode (BGEU (readBTypeFields fields gprRegFile))
-- U-Type
LUI fields -> Opcode (LUI (readUTypeFields fields gprRegFile))
AUIPC fields -> Opcode (AUIPC (readUTypeFields fields gprRegFile))
-- J-Type
JAL fields -> Opcode (JAL (readJTypeFields fields gprRegFile))
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 = fetchGPRRegVal rs1 gprRegFile
rs2_val = fetchGPRRegVal rs2 gprRegFile
in RTypeFields rd funct3 rs1_val rs2_val funct7
readITypeFields :: ITypeFields -> GPR -> ITypeFields
readITypeFields (ITypeFields rd funct3 rs1 imm) gprRegFile =
let rs1_val = fetchGPRRegVal rs1 gprRegFile
in ITypeFields rd funct3 rs1_val imm
readSTypeFields :: STypeFields -> GPR -> STypeFields
readSTypeFields (STypeFields funct3 rs1 rs2 imm12) gprRegFile =
let rs1_val = fetchGPRRegVal rs1 gprRegFile
rs2_val = fetchGPRRegVal rs2 gprRegFile
in STypeFields funct3 rs1_val rs2_val imm12
readBTypeFields :: BTypeFields -> GPR -> BTypeFields
readBTypeFields (BTypeFields funct3 rs1 rs2 imm13) gprRegFile =
let rs1_val = fetchGPRRegVal rs1 gprRegFile
rs2_val = fetchGPRRegVal rs2 gprRegFile
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
fetchGPRRegVal :: RegVal -> GPR -> RegVal
fetchGPRRegVal (Unpopulated idx) gprVal = Value idx (gprVal !! idx)
fetchGPRRegVal val@(Value _ _) _ = val -- Already populated, no change