Witch of Git - jade-rose/blob - toolchain/src/inst/encode.rs

   1 use super::{AluI, Data, Inst, Reg, Special, Target, U3};
   2 use std::io::{self, Write};
   3
   4 pub trait Encode {
   5     fn encode(&self, writer: &mut impl Write) -> io::Result<()>;
   6 }
   7
   8 fn reg(Reg(U3(x)): Reg) -> u8 {
   9     x
  10 }
  11
  12 fn sp(s: Special) -> u8 {
  13     match s {
  14         Special::Data(Data::D1) => 0b00,
  15         Special::Data(Data::D2) => 0b01,
  16         Special::Code => 0b10,
  17     }
  18 }
  19
  20 impl Encode for Inst {
  21     fn encode(&self, writer: &mut impl Write) -> io::Result<()> {
  22         match *self {
  23             Inst::Trap => writer.write(&[0x00])?,
  24             Inst::Jump(Target::Abs) => writer.write(&[0x04])?,
  25             Inst::Call(Target::Abs) => writer.write(&[0x05])?,
  26             Inst::Jump(Target::Off) => writer.write(&[0x06])?,
  27             Inst::Call(Target::Off) => writer.write(&[0x07])?,
  28             Inst::Swap(r) => writer.write(&[0x08 | reg(r)])?,
  29             Inst::GetR(r) => writer.write(&[0x10 | reg(r)])?,
  30             Inst::SetR(r) => writer.write(&[0x18 | reg(r)])?,
  31             Inst::Get(s) => writer.write(&[0x20 | sp(s)])?,
  32             Inst::Set(s) => writer.write(&[0x28 | sp(s)])?,
  33             Inst::Alu1(op) => writer.write(&[0x30 | op as u8])?,
  34             Inst::IsLt(r) => writer.write(&[0x38 | reg(r)])?,
  35             Inst::AluR(op, r) => writer.write(&[0x40 | (op as u8) << 3 | reg(r)])?,
  36             Inst::LdD(d, r, inc) => {
  37                 writer.write(&[0x80 | (d as u8) << 5 | (inc as u8) << 4 | reg(r)])?
  38             }
  39             Inst::StD(d, r, inc) => {
  40                 writer.write(&[0x88 | (d as u8) << 5 | (inc as u8) << 4 | reg(r)])?
  41             }
  42             Inst::AluI(alu) => match alu {
  43                 AluI::And(imm) => writer.write(&[0xf0, imm])?,
  44                 AluI::Ior(imm) => writer.write(&[0xf1, imm])?,
  45                 AluI::Xor(imm) => writer.write(&[0xf2, imm])?,
  46                 AluI::Add(imm) => writer.write(&[0xf3, imm.0 as u8])?,
  47                 AluI::Compact(op, imm) => writer.write(&[0xf3, 0x80 | (op as u8) << 3 | imm.0])?,
  48             },
  49             Inst::BEzI(off) => writer.write(&[0xf4, off as u8])?,
  50             Inst::Jump(Target::OffImm(off)) => writer.write(&[0xf6, off as u8])?,
  51             Inst::Call(Target::OffImm(off)) => writer.write(&[0xf7, off as u8])?,
  52         };
  53         Ok(())
  54     }
  55 }