private static void EmitAsrC(ILEmitterCtx context, bool setCarry, int shift)
{
if ((uint)shift >= 32)
{
context.EmitAsr(31);
if (setCarry)
{
context.Emit(OpCodes.Dup);
context.EmitLdc_I4(1);
context.Emit(OpCodes.And);
context.EmitStflg((int)PState.CBit);
}
}
else
{
if (setCarry)
{
context.Emit(OpCodes.Dup);
context.EmitLsr(shift - 1);
context.EmitLdc_I4(1);
context.Emit(OpCodes.And);
context.EmitStflg((int)PState.CBit);
}
context.EmitAsr(shift);
}
}
public static void EmitDataLoadOper2(ILEmitterCtx context)
{
switch (context.CurrOp)
{
case IOpCodeAluImm64 op:
context.EmitLdc_I(op.Imm);
break;
case IOpCodeAluRs64 op:
context.EmitLdintzr(op.Rm);
switch (op.ShiftType)
{
case ShiftType.Lsl: context.EmitLsl(op.Shift); break;
case ShiftType.Lsr: context.EmitLsr(op.Shift); break;
case ShiftType.Asr: context.EmitAsr(op.Shift); break;
case ShiftType.Ror: context.EmitRor(op.Shift); break;
}
break;
case IOpCodeAluRx64 op:
context.EmitLdintzr(op.Rm);
context.EmitCast(op.IntType);
context.EmitLsl(op.Shift);
break;
}
}
public static void EmitAluLoadOper2(ILEmitterCtx context, bool setCarry = true)
{
switch (context.CurrOp)
{
// ARM32.
case OpCode32AluImm op:
context.EmitLdc_I4(op.Imm);
if (op.SetFlags && op.IsRotated)
{
context.EmitLdc_I4((int)((uint)op.Imm >> 31));
context.EmitStflg((int)PState.CBit);
}
break;
case OpCode32AluRsImm op:
EmitLoadRmShiftedByImmediate(context, op, setCarry);
break;
case OpCodeT16AluImm8 op:
context.EmitLdc_I4(op.Imm);
break;
// ARM64.
case IOpCodeAluImm64 op:
context.EmitLdc_I(op.Imm);
break;
case IOpCodeAluRs64 op:
context.EmitLdintzr(op.Rm);
switch (op.ShiftType)
{
case ShiftType.Lsl: context.EmitLsl(op.Shift); break;
case ShiftType.Lsr: context.EmitLsr(op.Shift); break;
case ShiftType.Asr: context.EmitAsr(op.Shift); break;
case ShiftType.Ror: context.EmitRor(op.Shift); break;
}
break;
case IOpCodeAluRx64 op:
context.EmitLdintzr(op.Rm);
context.EmitCast(op.IntType);
context.EmitLsl(op.Shift);
break;
default: throw new InvalidOperationException();
}
}
public static void Sbfm(ILEmitterCtx context)
{
OpCodeBfm64 op = (OpCodeBfm64)context.CurrOp;
int bitsCount = op.GetBitsCount();
if (op.Pos + 1 == bitsCount)
{
EmitSbfmShift(context);
}
else if (op.Pos < op.Shift)
{
EmitSbfiz(context);
}
else if (op.Pos == 7 && op.Shift == 0)
{
EmitSbfmCast(context, OpCodes.Conv_I1);
}
else if (op.Pos == 15 && op.Shift == 0)
{
EmitSbfmCast(context, OpCodes.Conv_I2);
}
else if (op.Pos == 31 && op.Shift == 0)
{
EmitSbfmCast(context, OpCodes.Conv_I4);
}
else
{
EmitBfmLoadRn(context);
context.EmitLdintzr(op.Rn);
context.EmitLsl(bitsCount - 1 - op.Pos);
context.EmitAsr(bitsCount - 1);
context.EmitLdc_I(~op.TMask);
context.Emit(OpCodes.And);
context.Emit(OpCodes.Or);
context.EmitStintzr(op.Rd);
}
}
private static void EmitBfiz(ILEmitterCtx context, bool signed)
{
OpCodeBfm64 op = (OpCodeBfm64)context.CurrOp;
int width = op.Pos + 1;
context.EmitLdintzr(op.Rn);
context.EmitLsl(op.GetBitsCount() - width);
if (signed)
{
context.EmitAsr(op.Shift - width);
}
else
{
context.EmitLsr(op.Shift - width);
}
context.EmitStintzr(op.Rd);
}