Ryujinx/ARMeilleure/Instructions/InstEmitAluHelper.cs
2022-09-10 23:03:14 -03:00

613 lines
20 KiB
C#

using ARMeilleure.Decoders;
using ARMeilleure.IntermediateRepresentation;
using ARMeilleure.State;
using ARMeilleure.Translation;
using System;
using System.Diagnostics;
using static ARMeilleure.Instructions.InstEmitHelper;
using static ARMeilleure.IntermediateRepresentation.Operand.Factory;
namespace ARMeilleure.Instructions
{
static class InstEmitAluHelper
{
public static bool ShouldSetFlags(ArmEmitterContext context)
{
IOpCode32HasSetFlags op = (IOpCode32HasSetFlags)context.CurrOp;
if (op.SetFlags == null)
{
return !context.IsInIfThenBlock;
}
return op.SetFlags.Value;
}
public static void EmitNZFlagsCheck(ArmEmitterContext context, Operand d)
{
SetFlag(context, PState.NFlag, context.ICompareLess (d, Const(d.Type, 0)));
SetFlag(context, PState.ZFlag, context.ICompareEqual(d, Const(d.Type, 0)));
}
public static void EmitAdcsCCheck(ArmEmitterContext context, Operand n, Operand d)
{
// C = (Rd == Rn && CIn) || Rd < Rn
Operand cIn = GetFlag(PState.CFlag);
Operand cOut = context.BitwiseAnd(context.ICompareEqual(d, n), cIn);
cOut = context.BitwiseOr(cOut, context.ICompareLessUI(d, n));
SetFlag(context, PState.CFlag, cOut);
}
public static void EmitAddsCCheck(ArmEmitterContext context, Operand n, Operand d)
{
// C = Rd < Rn
SetFlag(context, PState.CFlag, context.ICompareLessUI(d, n));
}
public static void EmitAddsVCheck(ArmEmitterContext context, Operand n, Operand m, Operand d)
{
// V = (Rd ^ Rn) & ~(Rn ^ Rm) < 0
Operand vOut = context.BitwiseExclusiveOr(d, n);
vOut = context.BitwiseAnd(vOut, context.BitwiseNot(context.BitwiseExclusiveOr(n, m)));
vOut = context.ICompareLess(vOut, Const(vOut.Type, 0));
SetFlag(context, PState.VFlag, vOut);
}
public static void EmitSbcsCCheck(ArmEmitterContext context, Operand n, Operand m)
{
// C = (Rn == Rm && CIn) || Rn > Rm
Operand cIn = GetFlag(PState.CFlag);
Operand cOut = context.BitwiseAnd(context.ICompareEqual(n, m), cIn);
cOut = context.BitwiseOr(cOut, context.ICompareGreaterUI(n, m));
SetFlag(context, PState.CFlag, cOut);
}
public static void EmitSubsCCheck(ArmEmitterContext context, Operand n, Operand m)
{
// C = Rn >= Rm
SetFlag(context, PState.CFlag, context.ICompareGreaterOrEqualUI(n, m));
}
public static void EmitSubsVCheck(ArmEmitterContext context, Operand n, Operand m, Operand d)
{
// V = (Rd ^ Rn) & (Rn ^ Rm) < 0
Operand vOut = context.BitwiseExclusiveOr(d, n);
vOut = context.BitwiseAnd(vOut, context.BitwiseExclusiveOr(n, m));
vOut = context.ICompareLess(vOut, Const(vOut.Type, 0));
SetFlag(context, PState.VFlag, vOut);
}
public static Operand EmitReverseBits32Op(ArmEmitterContext context, Operand op)
{
Debug.Assert(op.Type == OperandType.I32);
Operand val = context.BitwiseOr(context.ShiftRightUI(context.BitwiseAnd(op, Const(0xaaaaaaaau)), Const(1)),
context.ShiftLeft(context.BitwiseAnd(op, Const(0x55555555u)), Const(1)));
val = context.BitwiseOr(context.ShiftRightUI(context.BitwiseAnd(val, Const(0xccccccccu)), Const(2)),
context.ShiftLeft(context.BitwiseAnd(val, Const(0x33333333u)), Const(2)));
val = context.BitwiseOr(context.ShiftRightUI(context.BitwiseAnd(val, Const(0xf0f0f0f0u)), Const(4)),
context.ShiftLeft(context.BitwiseAnd(val, Const(0x0f0f0f0fu)), Const(4)));
val = context.BitwiseOr(context.ShiftRightUI(context.BitwiseAnd(val, Const(0xff00ff00u)), Const(8)),
context.ShiftLeft(context.BitwiseAnd(val, Const(0x00ff00ffu)), Const(8)));
return context.BitwiseOr(context.ShiftRightUI(val, Const(16)), context.ShiftLeft(val, Const(16)));
}
public static Operand EmitReverseBytes16_64Op(ArmEmitterContext context, Operand op)
{
Debug.Assert(op.Type == OperandType.I64);
return context.BitwiseOr(context.ShiftRightUI(context.BitwiseAnd(op, Const(0xff00ff00ff00ff00ul)), Const(8)),
context.ShiftLeft(context.BitwiseAnd(op, Const(0x00ff00ff00ff00fful)), Const(8)));
}
public static Operand EmitReverseBytes16_32Op(ArmEmitterContext context, Operand op)
{
Debug.Assert(op.Type == OperandType.I32);
Operand val = EmitReverseBytes16_64Op(context, context.ZeroExtend32(OperandType.I64, op));
return context.ConvertI64ToI32(val);
}
private static void EmitAluWritePc(ArmEmitterContext context, Operand value)
{
Debug.Assert(value.Type == OperandType.I32);
if (((OpCode32)context.CurrOp).IsThumb)
{
bool isReturn = IsA32Return(context);
if (!isReturn)
{
context.StoreToContext();
}
InstEmitFlowHelper.EmitVirtualJump(context, value, isReturn);
}
else
{
EmitBxWritePc(context, value);
}
}
public static void EmitGenericAluStoreA32(ArmEmitterContext context, int rd, bool setFlags, Operand value)
{
Debug.Assert(value.Type == OperandType.I32);
if (rd == RegisterAlias.Aarch32Pc && setFlags)
{
if (setFlags)
{
// TODO: Load SPSR etc.
EmitBxWritePc(context, value);
}
else
{
EmitAluWritePc(context, value);
}
}
else
{
SetIntA32(context, rd, value);
}
}
public static Operand GetAluN(ArmEmitterContext context)
{
if (context.CurrOp is IOpCodeAlu op)
{
if (op.DataOp == DataOp.Logical || op is IOpCodeAluRs)
{
return GetIntOrZR(context, op.Rn);
}
else
{
return GetIntOrSP(context, op.Rn);
}
}
else if (context.CurrOp is IOpCode32Alu op32)
{
return GetIntA32(context, op32.Rn);
}
else
{
throw InvalidOpCodeType(context.CurrOp);
}
}
public static Operand GetAluM(ArmEmitterContext context, bool setCarry = true)
{
switch (context.CurrOp)
{
// ARM32.
case IOpCode32AluImm op:
{
if (ShouldSetFlags(context) && op.IsRotated && setCarry)
{
SetFlag(context, PState.CFlag, Const((uint)op.Immediate >> 31));
}
return Const(op.Immediate);
}
case IOpCode32AluImm16 op: return Const(op.Immediate);
case IOpCode32AluRsImm op: return GetMShiftedByImmediate(context, op, setCarry);
case IOpCode32AluRsReg op: return GetMShiftedByReg(context, op, setCarry);
case IOpCode32AluReg op: return GetIntA32(context, op.Rm);
// ARM64.
case IOpCodeAluImm op:
{
if (op.GetOperandType() == OperandType.I32)
{
return Const((int)op.Immediate);
}
else
{
return Const(op.Immediate);
}
}
case IOpCodeAluRs op:
{
Operand value = GetIntOrZR(context, op.Rm);
switch (op.ShiftType)
{
case ShiftType.Lsl: value = context.ShiftLeft (value, Const(op.Shift)); break;
case ShiftType.Lsr: value = context.ShiftRightUI(value, Const(op.Shift)); break;
case ShiftType.Asr: value = context.ShiftRightSI(value, Const(op.Shift)); break;
case ShiftType.Ror: value = context.RotateRight (value, Const(op.Shift)); break;
}
return value;
}
case IOpCodeAluRx op:
{
Operand value = GetExtendedM(context, op.Rm, op.IntType);
value = context.ShiftLeft(value, Const(op.Shift));
return value;
}
default: throw InvalidOpCodeType(context.CurrOp);
}
}
private static Exception InvalidOpCodeType(OpCode opCode)
{
return new InvalidOperationException($"Invalid OpCode type \"{opCode?.GetType().Name ?? "null"}\".");
}
// ARM32 helpers.
public static Operand GetMShiftedByImmediate(ArmEmitterContext context, IOpCode32AluRsImm op, bool setCarry)
{
Operand m = GetIntA32(context, op.Rm);
int shift = op.Immediate;
if (shift == 0)
{
switch (op.ShiftType)
{
case ShiftType.Lsr: shift = 32; break;
case ShiftType.Asr: shift = 32; break;
case ShiftType.Ror: shift = 1; break;
}
}
if (shift != 0)
{
setCarry &= ShouldSetFlags(context);
switch (op.ShiftType)
{
case ShiftType.Lsl: m = GetLslC(context, m, setCarry, shift); break;
case ShiftType.Lsr: m = GetLsrC(context, m, setCarry, shift); break;
case ShiftType.Asr: m = GetAsrC(context, m, setCarry, shift); break;
case ShiftType.Ror:
if (op.Immediate != 0)
{
m = GetRorC(context, m, setCarry, shift);
}
else
{
m = GetRrxC(context, m, setCarry);
}
break;
}
}
return m;
}
public static int DecodeImmShift(ShiftType shiftType, int shift)
{
if (shift == 0)
{
switch (shiftType)
{
case ShiftType.Lsr: shift = 32; break;
case ShiftType.Asr: shift = 32; break;
case ShiftType.Ror: shift = 1; break;
}
}
return shift;
}
public static Operand GetMShiftedByReg(ArmEmitterContext context, IOpCode32AluRsReg op, bool setCarry)
{
Operand m = GetIntA32(context, op.Rm);
Operand s = context.ZeroExtend8(OperandType.I32, GetIntA32(context, op.Rs));
Operand shiftIsZero = context.ICompareEqual(s, Const(0));
Operand zeroResult = m;
Operand shiftResult = m;
setCarry &= ShouldSetFlags(context);
switch (op.ShiftType)
{
case ShiftType.Lsl: shiftResult = EmitLslC(context, m, setCarry, s, shiftIsZero); break;
case ShiftType.Lsr: shiftResult = EmitLsrC(context, m, setCarry, s, shiftIsZero); break;
case ShiftType.Asr: shiftResult = EmitAsrC(context, m, setCarry, s, shiftIsZero); break;
case ShiftType.Ror: shiftResult = EmitRorC(context, m, setCarry, s, shiftIsZero); break;
}
return context.ConditionalSelect(shiftIsZero, zeroResult, shiftResult);
}
public static void EmitIfHelper(ArmEmitterContext context, Operand boolValue, Action action, bool expected = true)
{
Debug.Assert(boolValue.Type == OperandType.I32);
Operand endLabel = Label();
if (expected)
{
context.BranchIfFalse(endLabel, boolValue);
}
else
{
context.BranchIfTrue(endLabel, boolValue);
}
action();
context.MarkLabel(endLabel);
}
public static Operand EmitLslC(ArmEmitterContext context, Operand m, bool setCarry, Operand shift, Operand shiftIsZero)
{
Debug.Assert(m.Type == OperandType.I32 && shift.Type == OperandType.I32 && shiftIsZero.Type == OperandType.I32);
Operand shiftLarge = context.ICompareGreaterOrEqual(shift, Const(32));
Operand result = context.ShiftLeft(m, shift);
if (setCarry)
{
EmitIfHelper(context, shiftIsZero, () =>
{
Operand cOut = context.ShiftRightUI(m, context.Subtract(Const(32), shift));
cOut = context.BitwiseAnd(cOut, Const(1));
cOut = context.ConditionalSelect(context.ICompareGreater(shift, Const(32)), Const(0), cOut);
SetFlag(context, PState.CFlag, cOut);
}, false);
}
return context.ConditionalSelect(shiftLarge, Const(0), result);
}
public static Operand GetLslC(ArmEmitterContext context, Operand m, bool setCarry, int shift)
{
Debug.Assert(m.Type == OperandType.I32);
if ((uint)shift > 32)
{
return GetShiftByMoreThan32(context, setCarry);
}
else if (shift == 32)
{
if (setCarry)
{
SetCarryMLsb(context, m);
}
return Const(0);
}
else
{
if (setCarry)
{
Operand cOut = context.ShiftRightUI(m, Const(32 - shift));
cOut = context.BitwiseAnd(cOut, Const(1));
SetFlag(context, PState.CFlag, cOut);
}
return context.ShiftLeft(m, Const(shift));
}
}
public static Operand EmitLsrC(ArmEmitterContext context, Operand m, bool setCarry, Operand shift, Operand shiftIsZero)
{
Debug.Assert(m.Type == OperandType.I32 && shift.Type == OperandType.I32 && shiftIsZero.Type == OperandType.I32);
Operand shiftLarge = context.ICompareGreaterOrEqual(shift, Const(32));
Operand result = context.ShiftRightUI(m, shift);
if (setCarry)
{
EmitIfHelper(context, shiftIsZero, () =>
{
Operand cOut = context.ShiftRightUI(m, context.Subtract(shift, Const(1)));
cOut = context.BitwiseAnd(cOut, Const(1));
cOut = context.ConditionalSelect(context.ICompareGreater(shift, Const(32)), Const(0), cOut);
SetFlag(context, PState.CFlag, cOut);
}, false);
}
return context.ConditionalSelect(shiftLarge, Const(0), result);
}
public static Operand GetLsrC(ArmEmitterContext context, Operand m, bool setCarry, int shift)
{
Debug.Assert(m.Type == OperandType.I32);
if ((uint)shift > 32)
{
return GetShiftByMoreThan32(context, setCarry);
}
else if (shift == 32)
{
if (setCarry)
{
SetCarryMMsb(context, m);
}
return Const(0);
}
else
{
if (setCarry)
{
SetCarryMShrOut(context, m, shift);
}
return context.ShiftRightUI(m, Const(shift));
}
}
private static Operand GetShiftByMoreThan32(ArmEmitterContext context, bool setCarry)
{
if (setCarry)
{
SetFlag(context, PState.CFlag, Const(0));
}
return Const(0);
}
public static Operand EmitAsrC(ArmEmitterContext context, Operand m, bool setCarry, Operand shift, Operand shiftIsZero)
{
Debug.Assert(m.Type == OperandType.I32 && shift.Type == OperandType.I32 && shiftIsZero.Type == OperandType.I32);
Operand l32Result;
Operand ge32Result;
Operand less32 = context.ICompareLess(shift, Const(32));
ge32Result = context.ShiftRightSI(m, Const(31));
if (setCarry)
{
EmitIfHelper(context, context.BitwiseOr(less32, shiftIsZero), () =>
{
SetCarryMLsb(context, ge32Result);
}, false);
}
l32Result = context.ShiftRightSI(m, shift);
if (setCarry)
{
EmitIfHelper(context, context.BitwiseAnd(less32, context.BitwiseNot(shiftIsZero)), () =>
{
Operand cOut = context.ShiftRightUI(m, context.Subtract(shift, Const(1)));
cOut = context.BitwiseAnd(cOut, Const(1));
SetFlag(context, PState.CFlag, cOut);
});
}
return context.ConditionalSelect(less32, l32Result, ge32Result);
}
public static Operand GetAsrC(ArmEmitterContext context, Operand m, bool setCarry, int shift)
{
Debug.Assert(m.Type == OperandType.I32);
if ((uint)shift >= 32)
{
m = context.ShiftRightSI(m, Const(31));
if (setCarry)
{
SetCarryMLsb(context, m);
}
return m;
}
else
{
if (setCarry)
{
SetCarryMShrOut(context, m, shift);
}
return context.ShiftRightSI(m, Const(shift));
}
}
public static Operand EmitRorC(ArmEmitterContext context, Operand m, bool setCarry, Operand shift, Operand shiftIsZero)
{
Debug.Assert(m.Type == OperandType.I32 && shift.Type == OperandType.I32 && shiftIsZero.Type == OperandType.I32);
shift = context.BitwiseAnd(shift, Const(0x1f));
m = context.RotateRight(m, shift);
if (setCarry)
{
EmitIfHelper(context, shiftIsZero, () =>
{
SetCarryMMsb(context, m);
}, false);
}
return m;
}
public static Operand GetRorC(ArmEmitterContext context, Operand m, bool setCarry, int shift)
{
Debug.Assert(m.Type == OperandType.I32);
shift &= 0x1f;
m = context.RotateRight(m, Const(shift));
if (setCarry)
{
SetCarryMMsb(context, m);
}
return m;
}
public static Operand GetRrxC(ArmEmitterContext context, Operand m, bool setCarry)
{
Debug.Assert(m.Type == OperandType.I32);
// Rotate right by 1 with carry.
Operand cIn = context.Copy(GetFlag(PState.CFlag));
if (setCarry)
{
SetCarryMLsb(context, m);
}
m = context.ShiftRightUI(m, Const(1));
m = context.BitwiseOr(m, context.ShiftLeft(cIn, Const(31)));
return m;
}
private static void SetCarryMLsb(ArmEmitterContext context, Operand m)
{
Debug.Assert(m.Type == OperandType.I32);
SetFlag(context, PState.CFlag, context.BitwiseAnd(m, Const(1)));
}
private static void SetCarryMMsb(ArmEmitterContext context, Operand m)
{
Debug.Assert(m.Type == OperandType.I32);
SetFlag(context, PState.CFlag, context.ShiftRightUI(m, Const(31)));
}
private static void SetCarryMShrOut(ArmEmitterContext context, Operand m, int shift)
{
Debug.Assert(m.Type == OperandType.I32);
Operand cOut = context.ShiftRightUI(m, Const(shift - 1));
cOut = context.BitwiseAnd(cOut, Const(1));
SetFlag(context, PState.CFlag, cOut);
}
}
}