// Register.
private static bool r1(uint uInstr, XCore200Disassembler dasm)
{
var iReg = uInstr & 0xF;
dasm.ops.Add(new RegisterOperand(Registers.GpRegs[iReg]));
return(true);
}
// Register with immediate.
private static bool rus(uint uInstr, XCore200Disassembler dasm)
{
var base3 = (uInstr >> 6) & 0x1F;
if (base3 < 27)
{
return(false);
}
if (Bits.IsBitSet(uInstr, 5))
{
if (base3 == 31)
{
return(false);
}
base3 += 5;
}
base3 -= 27;
var imm = uInstr & 0x03;
var iReg = (uInstr >> 2) & 0x03;
imm += (base3 % 3) << 2;
base3 = base3 / 3;
iReg += (base3 % 3) << 2;
if (iReg >= 12)
{
return(false);
}
dasm.ops.Add(new RegisterOperand(Registers.GpRegs[iReg]));
dasm.ops.Add(new RegisterOperand(Registers.GpRegs[imm]));
return(true);
}
// Register with immediate.
private static bool rus_bitp(uint uInstr, XCore200Disassembler dasm)
{
var base3 = (uInstr >> 6) & 0x1F;
if (base3 < 27)
{
return(false);
}
if (Bits.IsBitSet(uInstr, 5))
{
if (base3 == 31)
{
return(false);
}
base3 += 5;
}
base3 -= 27;
var imm = uInstr & 0x03;
var iReg = (uInstr >> 2) & 0x03;
imm += (base3 % 3) << 2;
base3 = base3 / 3;
iReg += (base3 % 3) << 2;
if (iReg >= 12 || imm >= bitpos32.Length)
{
return(false);
}
imm = bitpos32[imm];
dasm.ops.Add(new RegisterOperand(Registers.GpRegs[iReg]));
dasm.ops.Add(ImmediateOperand.Word32(imm));
return(true);
}
// 6-bit immediate
private static bool u6(uint uInstr, XCore200Disassembler dasm)
{
var u = uInstr & 0x3F;
dasm.ops.Add(ImmediateOperand.Word32(u));
return(false);
}
private static bool r2us_bitp(uint uInstr, XCore200Disassembler dasm)
{
// Get low bits first.
var imm3 = uInstr & 0x03;
var iReg2 = (uInstr >> 2) & 0x03;
var iReg1 = (uInstr >> 4) & 0x03;
// Extract base3 field.
var base3 = (uInstr >> 6) & 0x1F;
imm3 += (base3 % 3) << 2;
base3 = base3 / 3;
iReg2 += (base3 % 3) << 2;
base3 = base3 / 3;
iReg1 += (base3 % 3) << 2;
if (iReg1 >= 12)
{
return(false);
}
imm3 = bitpos32[imm3];
dasm.ops.Add(new RegisterOperand(Registers.GpRegs[iReg1]));
dasm.ops.Add(new RegisterOperand(Registers.GpRegs[iReg2]));
dasm.ops.Add(ImmediateOperand.Word32(imm3));
return(true);
}
private static bool PcRel11_2(uint uInstr, XCore200Disassembler dasm)
{
var offset = pcRe11Field.ReadSigned(uInstr);
var addr = dasm.addr + 2 * offset;
dasm.ops.Add(AddressOperand.Create(addr));
return(true);
}
// 10-bit pc-relative negative displacement
private static bool u10_m_pc(uint uInstr, XCore200Disassembler dasm)
{
var displacement = (int)(uInstr & Bits.Mask(0, 10)) << 1;
var addr = dasm.addr - displacement;
dasm.ops.Add(AddressOperand.Create(addr));
return(true);
}
public override XCoreInstruction Decode(uint wInstr, XCore200Disassembler dasm)
{
if (!dasm.rdr.TryReadLeUInt16(out ushort u2))
{
return(dasm.CreateInvalidInstruction());
}
wInstr = (wInstr << 16) | u2;
return(subDecoder.Decode(wInstr, dasm));
}
//Register with 6-bit immediate
private static bool ru6(uint uInstr, XCore200Disassembler dasm)
{
var iReg = (uInstr >> 6) & 0xF;
var imm = (uInstr & 0x3F);
dasm.ops.Add(new RegisterOperand(Registers.GpRegs[iReg]));
dasm.ops.Add(ImmediateOperand.Word32(imm));
return(true);
}
//Register with 6-bit immediate added to PC
private static bool ru6_p_pc(uint uInstr, XCore200Disassembler dasm)
{
var iReg = (uInstr >> 6) & 0xF;
var imm = (uInstr & 0x3F) << 1;
var addr = dasm.addr + imm;
dasm.ops.Add(new RegisterOperand(Registers.GpRegs[iReg]));
dasm.ops.Add(AddressOperand.Create(addr));
return(true);
}
//Register with 6-bit immediate subtracted from PC
private static bool ru6_m_pc(uint uInstr, XCore200Disassembler dasm)
{
var iReg = (uInstr >> 6) & 0xF;
var imm = uInstr & 0x3F;
if ((imm & 1) != 0)
{
return(false); // Illegal address.
}
var addr = dasm.addr - imm;
dasm.ops.Add(new RegisterOperand(Registers.GpRegs[iReg]));
dasm.ops.Add(AddressOperand.Create(addr));
return(true);
}
public override XCoreInstruction Decode(uint wInstr, XCore200Disassembler dasm)
{
foreach (var m in mutators)
{
if (!m(wInstr, dasm))
{
return(dasm.CreateInvalidInstruction());
}
}
var instr = new XCoreInstruction
{
InstructionClass = iclass,
Mnemonic = mnemonic,
Operands = dasm.ops.ToArray()
};
return(instr);
}
// Six registers long.
private static bool l6r(uint uInstr, XCore200Disassembler dasm)
{
return(false);
}
