using ARMeilleure.Decoders;
using ARMeilleure.IntermediateRepresentation;
using ARMeilleure.State;
using ARMeilleure.Translation;
using System;
using static ARMeilleure.IntermediateRepresentation.Operand.Factory;
namespace ARMeilleure.Instructions
{
static class InstEmitHelper
{
public static Operand GetExtendedM(ArmEmitterContext context, int rm, IntType type)
{
Operand value = GetIntOrZR(context, rm);
switch (type)
{
case IntType.UInt8:
value = context.ZeroExtend8(value.Type, value);
break;
case IntType.UInt16:
value = context.ZeroExtend16(value.Type, value);
break;
case IntType.UInt32:
value = context.ZeroExtend32(value.Type, value);
break;
case IntType.Int8:
value = context.SignExtend8(value.Type, value);
break;
case IntType.Int16:
value = context.SignExtend16(value.Type, value);
break;
case IntType.Int32:
value = context.SignExtend32(value.Type, value);
break;
}
return value;
}
public static Operand GetIntA32(ArmEmitterContext context, int regIndex)
{
if (regIndex == RegisterAlias.Aarch32Pc)
{
OpCode32 op = (OpCode32)context.CurrOp;
return Const((int)op.GetPc());
}
else
{
return Register(GetRegisterAlias(context.Mode, regIndex), RegisterType.Integer, OperandType.I32);
}
}
public static Operand GetIntA32AlignedPC(ArmEmitterContext context, int regIndex)
{
if (regIndex == RegisterAlias.Aarch32Pc)
{
OpCode32 op = (OpCode32)context.CurrOp;
return Const((int)(op.GetPc() & 0xfffffffc));
}
else
{
return Register(GetRegisterAlias(context.Mode, regIndex), RegisterType.Integer, OperandType.I32);
}
}
public static Operand GetVecA32(int regIndex)
{
return Register(regIndex, RegisterType.Vector, OperandType.V128);
}
public static void SetIntA32(ArmEmitterContext context, int regIndex, Operand value)
{
if (regIndex == RegisterAlias.Aarch32Pc)
{
if (!IsA32Return(context))
{
context.StoreToContext();
}
EmitBxWritePc(context, value);
}
else
{
if (value.Type == OperandType.I64)
{
value = context.ConvertI64ToI32(value);
}
Operand reg = Register(GetRegisterAlias(context.Mode, regIndex), RegisterType.Integer, OperandType.I32);
context.Copy(reg, value);
}
}
public static int GetRegisterAlias(Aarch32Mode mode, int regIndex)
{
// Only registers >= 8 are banked,
// with registers in the range [8, 12] being
// banked for the FIQ mode, and registers
// 13 and 14 being banked for all modes.
if ((uint)regIndex < 8)
{
return regIndex;
}
return GetBankedRegisterAlias(mode, regIndex);
}
public static int GetBankedRegisterAlias(Aarch32Mode mode, int regIndex)
{
return regIndex switch
{
#pragma warning disable IDE0055 // Disable formatting
8 => mode == Aarch32Mode.Fiq ? RegisterAlias.R8Fiq : RegisterAlias.R8Usr,
9 => mode == Aarch32Mode.Fiq ? RegisterAlias.R9Fiq : RegisterAlias.R9Usr,
10 => mode == Aarch32Mode.Fiq ? RegisterAlias.R10Fiq : RegisterAlias.R10Usr,
11 => mode == Aarch32Mode.Fiq ? RegisterAlias.R11Fiq : RegisterAlias.R11Usr,
12 => mode == Aarch32Mode.Fiq ? RegisterAlias.R12Fiq : RegisterAlias.R12Usr,
13 => mode switch
{
Aarch32Mode.User or Aarch32Mode.System => RegisterAlias.SpUsr,
Aarch32Mode.Fiq => RegisterAlias.SpFiq,
Aarch32Mode.Irq => RegisterAlias.SpIrq,
Aarch32Mode.Supervisor => RegisterAlias.SpSvc,
Aarch32Mode.Abort => RegisterAlias.SpAbt,
Aarch32Mode.Hypervisor => RegisterAlias.SpHyp,
Aarch32Mode.Undefined => RegisterAlias.SpUnd,
_ => throw new ArgumentException($"No such AArch32Mode: {mode}", nameof(mode)),
},
14 => mode switch
{
Aarch32Mode.User or Aarch32Mode.Hypervisor or Aarch32Mode.System => RegisterAlias.LrUsr,
Aarch32Mode.Fiq => RegisterAlias.LrFiq,
Aarch32Mode.Irq => RegisterAlias.LrIrq,
Aarch32Mode.Supervisor => RegisterAlias.LrSvc,
Aarch32Mode.Abort => RegisterAlias.LrAbt,
Aarch32Mode.Undefined => RegisterAlias.LrUnd,
_ => throw new ArgumentException($"No such AArch32Mode: {mode}", nameof(mode)),
},
_ => throw new ArgumentOutOfRangeException(nameof(regIndex), regIndex, null),
#pragma warning restore IDE0055
};
}
public static bool IsA32Return(ArmEmitterContext context)
{
return context.CurrOp switch
{
IOpCode32MemMult => true, // Setting PC using LDM is nearly always a return.
OpCode32AluRsImm op => op.Rm == RegisterAlias.Aarch32Lr,
OpCode32AluRsReg op => op.Rm == RegisterAlias.Aarch32Lr,
OpCode32AluReg op => op.Rm == RegisterAlias.Aarch32Lr,
OpCode32Mem op => op.Rn == RegisterAlias.Aarch32Sp && op.WBack && !op.Index, // Setting PC to an address stored on the stack is nearly always a return.
_ => false,
};
}
public static void EmitBxWritePc(ArmEmitterContext context, Operand pc, int sourceRegister = 0)
{
bool isReturn = sourceRegister == RegisterAlias.Aarch32Lr || IsA32Return(context);
Operand mode = context.BitwiseAnd(pc, Const(1));
SetFlag(context, PState.TFlag, mode);
Operand addr = context.ConditionalSelect(mode, context.BitwiseAnd(pc, Const(~1)), context.BitwiseAnd(pc, Const(~3)));
InstEmitFlowHelper.EmitVirtualJump(context, addr, isReturn);
}
public static Operand GetIntOrZR(ArmEmitterContext context, int regIndex)
{
if (regIndex == RegisterConsts.ZeroIndex)
{
OperandType type = context.CurrOp.GetOperandType();
return type == OperandType.I32 ? Const(0) : Const(0L);
}
else
{
return GetIntOrSP(context, regIndex);
}
}
public static void SetIntOrZR(ArmEmitterContext context, int regIndex, Operand value)
{
if (regIndex == RegisterConsts.ZeroIndex)
{
return;
}
SetIntOrSP(context, regIndex, value);
}
public static Operand GetIntOrSP(ArmEmitterContext context, int regIndex)
{
Operand value = Register(regIndex, RegisterType.Integer, OperandType.I64);
if (context.CurrOp.RegisterSize == RegisterSize.Int32)
{
value = context.ConvertI64ToI32(value);
}
return value;
}
public static void SetIntOrSP(ArmEmitterContext context, int regIndex, Operand value)
{
Operand reg = Register(regIndex, RegisterType.Integer, OperandType.I64);
if (value.Type == OperandType.I32)
{
value = context.ZeroExtend32(OperandType.I64, value);
}
context.Copy(reg, value);
}
public static Operand GetVec(int regIndex)
{
return Register(regIndex, RegisterType.Vector, OperandType.V128);
}
public static Operand GetFlag(PState stateFlag)
{
return Register((int)stateFlag, RegisterType.Flag, OperandType.I32);
}
public static Operand GetFpFlag(FPState stateFlag)
{
return Register((int)stateFlag, RegisterType.FpFlag, OperandType.I32);
}
public static void SetFlag(ArmEmitterContext context, PState stateFlag, Operand value)
{
context.Copy(GetFlag(stateFlag), value);
context.MarkFlagSet(stateFlag);
}
public static void SetFpFlag(ArmEmitterContext context, FPState stateFlag, Operand value)
{
context.Copy(GetFpFlag(stateFlag), value);
}
}
}