public static void Ubfm(ILEmitterCtx context)
{
OpCodeBfm64 op = (OpCodeBfm64)context.CurrOp;
if (op.Pos + 1 == op.GetBitsCount())
{
EmitUbfmShift(context);
}
else if (op.Pos < op.Shift)
{
EmitUbfiz(context);
}
else if (op.Pos + 1 == op.Shift)
{
EmitBfmLsl(context);
}
else if (op.Pos == 7 && op.Shift == 0)
{
EmitUbfmCast(context, OpCodes.Conv_U1);
}
else if (op.Pos == 15 && op.Shift == 0)
{
EmitUbfmCast(context, OpCodes.Conv_U2);
}
else
{
EmitBfmLoadRn(context);
context.EmitStintzr(op.Rd);
}
}
private static void EmitBfmLsl(ILEmitterCtx context)
{
OpCodeBfm64 op = (OpCodeBfm64)context.CurrOp;
context.EmitLdintzr(op.Rn);
context.EmitLsl(op.GetBitsCount() - op.Shift);
context.EmitStintzr(op.Rd);
}
public static void Bfm(ILEmitterCtx context)
{
OpCodeBfm64 op = (OpCodeBfm64)context.CurrOp;
if (op.Pos < op.Shift)
{
//BFI.
context.EmitLdintzr(op.Rn);
int shift = op.GetBitsCount() - op.Shift;
int width = op.Pos + 1;
long mask = (long)(ulong.MaxValue >> (64 - width));
context.EmitLdc_I(mask);
context.Emit(OpCodes.And);
context.EmitLsl(shift);
context.EmitLdintzr(op.Rd);
context.EmitLdc_I(~(mask << shift));
context.Emit(OpCodes.And);
context.Emit(OpCodes.Or);
context.EmitStintzr(op.Rd);
}
else
{
//BFXIL.
context.EmitLdintzr(op.Rn);
context.EmitLsr(op.Shift);
int width = op.Pos - op.Shift + 1;
long mask = (long)(ulong.MaxValue >> (64 - width));
context.EmitLdc_I(mask);
context.Emit(OpCodes.And);
context.EmitLdintzr(op.Rd);
context.EmitLdc_I(~mask);
context.Emit(OpCodes.And);
context.Emit(OpCodes.Or);
context.EmitStintzr(op.Rd);
}
}
private static void EmitBfmLoadRn(ILEmitterCtx context)
{
OpCodeBfm64 op = (OpCodeBfm64)context.CurrOp;
context.EmitLdintzr(op.Rn);
context.EmitRor(op.Shift);
context.EmitLdc_I(op.WMask & op.TMask);
context.Emit(OpCodes.And);
}
private static void EmitBfmShift(ILEmitterCtx context, bool signed)
{
OpCodeBfm64 op = (OpCodeBfm64)context.CurrOp;
context.EmitLdintzr(op.Rn);
context.EmitLdc_I4(op.Shift);
context.Emit(signed
? OpCodes.Shr
: OpCodes.Shr_Un);
context.EmitStintzr(op.Rd);
}
private static void EmitBfmCast(ILEmitterCtx context, OpCode ilOp, bool signed)
{
OpCodeBfm64 op = (OpCodeBfm64)context.CurrOp;
context.EmitLdintzr(op.Rn);
context.Emit(ilOp);
if (op.RegisterSize != RegisterSize.Int32)
{
context.Emit(signed
? OpCodes.Conv_I8
: OpCodes.Conv_U8);
}
context.EmitStintzr(op.Rd);
}
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);
}
}
public static void Bfm(ILEmitterCtx context)
{
OpCodeBfm64 op = (OpCodeBfm64)context.CurrOp;
EmitBfmLoadRn(context);
context.EmitLdintzr(op.Rd);
context.EmitLdc_I(~op.WMask & op.TMask);
context.Emit(OpCodes.And);
context.Emit(OpCodes.Or);
context.EmitLdintzr(op.Rd);
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);
}
