JinxRyu/ARMeilleure/Instructions/InstEmitAluHelper.cs
LDj3SNuD 8c85bdf2ed Implemented fast paths for: (#841)
* cpu-misc_opt

* B = ~b

* ;
2019-12-07 13:45:32 +01:00

351 lines
11 KiB
C#

using ARMeilleure.Decoders;
using ARMeilleure.IntermediateRepresentation;
using ARMeilleure.State;
using ARMeilleure.Translation;
using System;
using static ARMeilleure.Instructions.InstEmitHelper;
using static ARMeilleure.IntermediateRepresentation.OperandHelper;
namespace ARMeilleure.Instructions
{
static class InstEmitAluHelper
{
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 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 OpCode32AluImm op:
{
if (op.SetFlags && op.IsRotated)
{
SetFlag(context, PState.CFlag, Const((uint)op.Immediate >> 31));
}
return Const(op.Immediate);
}
case OpCode32AluRsImm op: return GetMShiftedByImmediate(context, op, setCarry);
case OpCodeT16AluImm8 op: return Const(op.Immediate);
// 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.
private static Operand GetMShiftedByImmediate(ArmEmitterContext context, OpCode32AluRsImm op, bool setCarry)
{
Operand m = GetIntA32(context, op.Rm);
int shift = op.Imm;
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 &= op.SetFlags;
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.Imm != 0)
{
m = GetRorC(context, m, setCarry, shift);
}
else
{
m = GetRrxC(context, m, setCarry);
}
break;
}
}
return m;
}
private static Operand GetLslC(ArmEmitterContext context, Operand m, bool setCarry, int shift)
{
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));
}
}
private static Operand GetLsrC(ArmEmitterContext context, Operand m, bool setCarry, int shift)
{
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);
}
private static Operand GetAsrC(ArmEmitterContext context, Operand m, bool setCarry, int shift)
{
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));
}
}
private static Operand GetRorC(ArmEmitterContext context, Operand m, bool setCarry, int shift)
{
shift &= 0x1f;
m = context.RotateRight(m, Const(shift));
if (setCarry)
{
SetCarryMMsb(context, m);
}
return m;
}
private static Operand GetRrxC(ArmEmitterContext context, Operand m, bool setCarry)
{
// 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)
{
SetFlag(context, PState.CFlag, context.BitwiseAnd(m, Const(1)));
}
private static void SetCarryMMsb(ArmEmitterContext context, Operand m)
{
SetFlag(context, PState.CFlag, context.ShiftRightUI(m, Const(31)));
}
private static void SetCarryMShrOut(ArmEmitterContext context, Operand m, int shift)
{
Operand cOut = context.ShiftRightUI(m, Const(shift - 1));
cOut = context.BitwiseAnd(cOut, Const(1));
SetFlag(context, PState.CFlag, cOut);
}
}
}