Ryujinx/Ryujinx.Graphics.Gpu/MacroInterpreter.cs
2020-04-25 23:56:56 +10:00

500 lines
No EOL
15 KiB
C#

using Ryujinx.Common.Logging;
using Ryujinx.Graphics.Gpu.State;
using System;
using System.Collections.Generic;
namespace Ryujinx.Graphics.Gpu
{
/// <summary>
/// Macro code interpreter.
/// </summary>
class MacroInterpreter
{
private enum AssignmentOperation
{
IgnoreAndFetch = 0,
Move = 1,
MoveAndSetMaddr = 2,
FetchAndSend = 3,
MoveAndSend = 4,
FetchAndSetMaddr = 5,
MoveAndSetMaddrThenFetchAndSend = 6,
MoveAndSetMaddrThenSendHigh = 7
}
private enum AluOperation
{
AluReg = 0,
AddImmediate = 1,
BitfieldReplace = 2,
BitfieldExtractLslImm = 3,
BitfieldExtractLslReg = 4,
ReadImmediate = 5
}
private enum AluRegOperation
{
Add = 0,
AddWithCarry = 1,
Subtract = 2,
SubtractWithBorrow = 3,
BitwiseExclusiveOr = 8,
BitwiseOr = 9,
BitwiseAnd = 10,
BitwiseAndNot = 11,
BitwiseNotAnd = 12
}
public Queue<int> Fifo { get; }
private int[] _gprs;
private int _methAddr;
private int _methIncr;
private bool _carry;
private int _opCode;
private int _pipeOp;
private bool _ignoreExitFlag;
private int _pc;
private ShadowRamControl _shadowCtrl;
/// <summary>
/// Creates a new instance of the macro code interpreter.
/// </summary>
public MacroInterpreter()
{
Fifo = new Queue<int>();
_gprs = new int[8];
}
/// <summary>
/// Executes a macro program until it exits.
/// </summary>
/// <param name="mme">Code of the program to execute</param>
/// <param name="position">Start position to execute</param>
/// <param name="param">Optional argument passed to the program, 0 if not used</param>
/// <param name="shadowCtrl">Shadow RAM control register value</param>
/// <param name="state">Current GPU state</param>
public void Execute(int[] mme, int position, int param, ShadowRamControl shadowCtrl, GpuState state)
{
Reset();
_gprs[1] = param;
_pc = position;
_shadowCtrl = shadowCtrl;
FetchOpCode(mme);
while (Step(mme, state));
// Due to the delay slot, we still need to execute
// one more instruction before we actually exit.
Step(mme, state);
}
/// <summary>
/// Resets the internal interpreter state.
/// Call each time you run a new program.
/// </summary>
private void Reset()
{
for (int index = 0; index < _gprs.Length; index++)
{
_gprs[index] = 0;
}
_methAddr = 0;
_methIncr = 0;
_carry = false;
}
/// <summary>
/// Executes a single instruction of the program.
/// </summary>
/// <param name="mme">Program code to execute</param>
/// <param name="state">Current GPU state</param>
/// <returns>True to continue execution, false if the program exited</returns>
private bool Step(int[] mme, GpuState state)
{
int baseAddr = _pc - 1;
FetchOpCode(mme);
if ((_opCode & 7) < 7)
{
// Operation produces a value.
AssignmentOperation asgOp = (AssignmentOperation)((_opCode >> 4) & 7);
int result = GetAluResult(state);
switch (asgOp)
{
// Fetch parameter and ignore result.
case AssignmentOperation.IgnoreAndFetch:
{
SetDstGpr(FetchParam());
break;
}
// Move result.
case AssignmentOperation.Move:
{
SetDstGpr(result);
break;
}
// Move result and use as Method Address.
case AssignmentOperation.MoveAndSetMaddr:
{
SetDstGpr(result);
SetMethAddr(result);
break;
}
// Fetch parameter and send result.
case AssignmentOperation.FetchAndSend:
{
SetDstGpr(FetchParam());
Send(state, result);
break;
}
// Move and send result.
case AssignmentOperation.MoveAndSend:
{
SetDstGpr(result);
Send(state, result);
break;
}
// Fetch parameter and use result as Method Address.
case AssignmentOperation.FetchAndSetMaddr:
{
SetDstGpr(FetchParam());
SetMethAddr(result);
break;
}
// Move result and use as Method Address, then fetch and send parameter.
case AssignmentOperation.MoveAndSetMaddrThenFetchAndSend:
{
SetDstGpr(result);
SetMethAddr(result);
Send(state, FetchParam());
break;
}
// Move result and use as Method Address, then send bits 17:12 of result.
case AssignmentOperation.MoveAndSetMaddrThenSendHigh:
{
SetDstGpr(result);
SetMethAddr(result);
Send(state, (result >> 12) & 0x3f);
break;
}
}
}
else
{
// Branch.
bool onNotZero = ((_opCode >> 4) & 1) != 0;
bool taken = onNotZero
? GetGprA() != 0
: GetGprA() == 0;
if (taken)
{
_pc = baseAddr + GetImm();
bool noDelays = (_opCode & 0x20) != 0;
if (noDelays)
{
FetchOpCode(mme);
}
else
{
// The delay slot instruction exit flag should be ignored.
_ignoreExitFlag = true;
}
return true;
}
}
bool exit = (_opCode & 0x80) != 0 && !_ignoreExitFlag;
_ignoreExitFlag = false;
return !exit;
}
/// <summary>
/// Fetches a single operation code from the program code.
/// </summary>
/// <param name="mme">Program code</param>
private void FetchOpCode(int[] mme)
{
_opCode = _pipeOp;
_pipeOp = mme[_pc++];
}
/// <summary>
/// Gets the result of the current Arithmetic and Logic unit operation.
/// </summary>
/// <param name="state">Current GPU state</param>
/// <returns>Operation result</returns>
private int GetAluResult(GpuState state)
{
AluOperation op = (AluOperation)(_opCode & 7);
switch (op)
{
case AluOperation.AluReg:
{
AluRegOperation aluOp = (AluRegOperation)((_opCode >> 17) & 0x1f);
return GetAluResult(aluOp, GetGprA(), GetGprB());
}
case AluOperation.AddImmediate:
{
return GetGprA() + GetImm();
}
case AluOperation.BitfieldReplace:
case AluOperation.BitfieldExtractLslImm:
case AluOperation.BitfieldExtractLslReg:
{
int bfSrcBit = (_opCode >> 17) & 0x1f;
int bfSize = (_opCode >> 22) & 0x1f;
int bfDstBit = (_opCode >> 27) & 0x1f;
int bfMask = (1 << bfSize) - 1;
int dst = GetGprA();
int src = GetGprB();
switch (op)
{
case AluOperation.BitfieldReplace:
{
src = (int)((uint)src >> bfSrcBit) & bfMask;
dst &= ~(bfMask << bfDstBit);
dst |= src << bfDstBit;
return dst;
}
case AluOperation.BitfieldExtractLslImm:
{
src = (int)((uint)src >> dst) & bfMask;
return src << bfDstBit;
}
case AluOperation.BitfieldExtractLslReg:
{
src = (int)((uint)src >> bfSrcBit) & bfMask;
return src << dst;
}
}
break;
}
case AluOperation.ReadImmediate:
{
return Read(state, GetGprA() + GetImm());
}
}
throw new ArgumentException(nameof(_opCode));
}
/// <summary>
/// Gets the result of an Arithmetic and Logic operation using registers.
/// </summary>
/// <param name="aluOp">Arithmetic and Logic unit operation with registers</param>
/// <param name="a">First operand value</param>
/// <param name="b">Second operand value</param>
/// <returns>Operation result</returns>
private int GetAluResult(AluRegOperation aluOp, int a, int b)
{
switch (aluOp)
{
case AluRegOperation.Add:
{
ulong result = (ulong)a + (ulong)b;
_carry = result > 0xffffffff;
return (int)result;
}
case AluRegOperation.AddWithCarry:
{
ulong result = (ulong)a + (ulong)b + (_carry ? 1UL : 0UL);
_carry = result > 0xffffffff;
return (int)result;
}
case AluRegOperation.Subtract:
{
ulong result = (ulong)a - (ulong)b;
_carry = result < 0x100000000;
return (int)result;
}
case AluRegOperation.SubtractWithBorrow:
{
ulong result = (ulong)a - (ulong)b - (_carry ? 0UL : 1UL);
_carry = result < 0x100000000;
return (int)result;
}
case AluRegOperation.BitwiseExclusiveOr: return a ^ b;
case AluRegOperation.BitwiseOr: return a | b;
case AluRegOperation.BitwiseAnd: return a & b;
case AluRegOperation.BitwiseAndNot: return a & ~b;
case AluRegOperation.BitwiseNotAnd: return ~(a & b);
}
throw new ArgumentOutOfRangeException(nameof(aluOp));
}
/// <summary>
/// Extracts a 32-bits signed integer constant from the current operation code.
/// </summary>
/// <returns>The 32-bits immediate value encoded at the current operation code</returns>
private int GetImm()
{
// Note: The immediate is signed, the sign-extension is intended here.
return _opCode >> 14;
}
/// <summary>
/// Sets the current method address, for method calls.
/// </summary>
/// <param name="value">Packed address and increment value</param>
private void SetMethAddr(int value)
{
_methAddr = (value >> 0) & 0xfff;
_methIncr = (value >> 12) & 0x3f;
}
/// <summary>
/// Sets the destination register value.
/// </summary>
/// <param name="value">Value to set (usually the operation result)</param>
private void SetDstGpr(int value)
{
_gprs[(_opCode >> 8) & 7] = value;
}
/// <summary>
/// Gets first operand value from the respective register.
/// </summary>
/// <returns>Operand value</returns>
private int GetGprA()
{
return GetGprValue((_opCode >> 11) & 7);
}
/// <summary>
/// Gets second operand value from the respective register.
/// </summary>
/// <returns>Operand value</returns>
private int GetGprB()
{
return GetGprValue((_opCode >> 14) & 7);
}
/// <summary>
/// Gets the value from a register, or 0 if the R0 register is specified.
/// </summary>
/// <param name="index">Index of the register</param>
/// <returns>Register value</returns>
private int GetGprValue(int index)
{
return index != 0 ? _gprs[index] : 0;
}
/// <summary>
/// Fetches a call argument from the call argument FIFO.
/// </summary>
/// <returns>The call argument, or 0 if the FIFO is empty</returns>
private int FetchParam()
{
if (!Fifo.TryDequeue(out int value))
{
Logger.PrintWarning(LogClass.Gpu, "Macro attempted to fetch an inexistent argument.");
return 0;
}
return value;
}
/// <summary>
/// Reads data from a GPU register.
/// </summary>
/// <param name="state">Current GPU state</param>
/// <param name="reg">Register offset to read</param>
/// <returns>GPU register value</returns>
private int Read(GpuState state, int reg)
{
return state.Read(reg);
}
/// <summary>
/// Performs a GPU method call.
/// </summary>
/// <param name="state">Current GPU state</param>
/// <param name="value">Call argument</param>
private void Send(GpuState state, int value)
{
MethodParams meth = new MethodParams(_methAddr, value);
state.CallMethod(meth, _shadowCtrl);
_methAddr += _methIncr;
}
}
}