RiscV-Formal/hs/Read.hs

109 lines
4.6 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 opcode addr) riscvCPU =
let
gprRegFile = gpr riscvCPU
opcode' = case opcode of
-- R-Type
ADD fields -> (ADD (readRTypeFields fields gprRegFile))
SUB fields -> (SUB (readRTypeFields fields gprRegFile))
XOR fields -> (XOR (readRTypeFields fields gprRegFile))
OR fields -> (OR (readRTypeFields fields gprRegFile))
AND fields -> (AND (readRTypeFields fields gprRegFile))
SLL fields -> (SLL (readRTypeFields fields gprRegFile))
SRL fields -> (SRL (readRTypeFields fields gprRegFile))
SRA fields -> (SRA (readRTypeFields fields gprRegFile))
SLT fields -> (SLT (readRTypeFields fields gprRegFile))
SLTU fields -> (SLTU (readRTypeFields fields gprRegFile))
-- I-Type
ADDI fields -> (ADDI (readITypeFields fields gprRegFile))
XORI fields -> (XORI (readITypeFields fields gprRegFile))
ORI fields -> (ORI (readITypeFields fields gprRegFile))
ANDI fields -> (ANDI (readITypeFields fields gprRegFile))
SLLI fields -> (SLLI (readITypeFields fields gprRegFile))
SRLI fields -> (SRLI (readITypeFields fields gprRegFile))
SRAI fields -> (SRAI (readITypeFields fields gprRegFile))
SLTI fields -> (SLTI (readITypeFields fields gprRegFile))
SLTIU fields -> (SLTIU (readITypeFields fields gprRegFile))
LB fields -> (LB (readITypeFields fields gprRegFile))
LH fields -> (LH (readITypeFields fields gprRegFile))
LW fields -> (LW (readITypeFields fields gprRegFile))
LBU fields -> (LBU (readITypeFields fields gprRegFile))
LHU fields -> (LHU (readITypeFields fields gprRegFile))
JALR fields -> (JALR (readITypeFields fields gprRegFile))
ECALL fields -> (ECALL (readITypeFields fields gprRegFile)) -- No regs needed, but consistent
EBREAK fields -> (EBREAK (readITypeFields fields gprRegFile)) -- Ditto
-- S-Type
SB fields -> (SB (readSTypeFields fields gprRegFile))
SH fields -> (SH (readSTypeFields fields gprRegFile))
SW fields -> (SW (readSTypeFields fields gprRegFile))
-- B-Type
BEQ fields -> (BEQ (readBTypeFields fields gprRegFile))
BNE fields -> (BNE (readBTypeFields fields gprRegFile))
BLT fields -> (BLT (readBTypeFields fields gprRegFile))
BGE fields -> (BGE (readBTypeFields fields gprRegFile))
BLTU fields -> (BLTU (readBTypeFields fields gprRegFile))
BGEU fields -> (BGEU (readBTypeFields fields gprRegFile))
-- U-Type
LUI fields -> (LUI (readUTypeFields fields gprRegFile))
AUIPC fields -> (AUIPC (readUTypeFields fields gprRegFile))
-- J-Type
JAL fields -> (JAL (readJTypeFields fields gprRegFile))
in
Opcode opcode' addr
read (DecodeException e addr) _ = DecodeException e addr
read (InstructionException e addr) _ = InstructionException e addr
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