public static void Icmp(EmitterContext context)
{
OpCode op = context.CurrOp;
bool isSigned = op.RawOpCode.Extract(48);
IntegerCondition cmpOp = (IntegerCondition)op.RawOpCode.Extract(49, 3);
Operand srcA = GetSrcA(context);
Operand srcB = GetSrcB(context);
Operand srcC = GetSrcC(context);
Operand cmpRes = GetIntComparison(context, cmpOp, srcC, Const(0), isSigned);
Operand res = context.ConditionalSelect(cmpRes, srcA, srcB);
context.Copy(GetDest(context), res);
}
public static void Isetp(EmitterContext context)
{
OpCodeSet op = (OpCodeSet)context.CurrOp;
bool isSigned = op.RawOpCode.Extract(48);
IntegerCondition cmpOp = (IntegerCondition)op.RawOpCode.Extract(49, 3);
Operand srcA = GetSrcA(context);
Operand srcB = GetSrcB(context);
Operand p0Res = GetIntComparison(context, cmpOp, srcA, srcB, isSigned, op.Extended);
Operand p1Res = context.BitwiseNot(p0Res);
Operand pred = GetPredicate39(context);
p0Res = GetPredLogicalOp(context, op.LogicalOp, p0Res, pred);
p1Res = GetPredLogicalOp(context, op.LogicalOp, p1Res, pred);
context.Copy(Register(op.Predicate3), p0Res);
context.Copy(Register(op.Predicate0), p1Res);
}
public static void Iset(EmitterContext context)
{
OpCodeSet op = (OpCodeSet)context.CurrOp;
bool boolFloat = op.RawOpCode.Extract(44);
bool isSigned = op.RawOpCode.Extract(48);
IntegerCondition cmpOp = (IntegerCondition)op.RawOpCode.Extract(49, 3);
Operand srcA = GetSrcA(context);
Operand srcB = GetSrcB(context);
Operand res = GetIntComparison(context, cmpOp, srcA, srcB, isSigned);
Operand pred = GetPredicate39(context);
res = GetPredLogicalOp(context, op.LogicalOp, res, pred);
Operand dest = GetDest(context);
if (boolFloat)
{
res = context.ConditionalSelect(res, ConstF(1), Const(0));
context.Copy(dest, res);
SetFPZnFlags(context, res, op.SetCondCode);
}
else
{
context.Copy(dest, res);
SetZnFlags(context, res, op.SetCondCode, op.Extended);
}
// TODO: X
}
private static Operand GetIntComparisonExtended(
EmitterContext context,
IntegerCondition cond,
Operand srcA,
Operand srcB,
bool isSigned)
{
Operand res;
if (cond == IntegerCondition.Always)
{
res = Const(IrConsts.True);
}
else if (cond == IntegerCondition.Never)
{
res = Const(IrConsts.False);
}
else
{
res = context.ISubtract(srcA, srcB);
res = context.IAdd(res, context.BitwiseNot(GetCF()));
switch (cond)
{
case Decoders.IntegerCondition.Equal: // r = xh == yh && xl == yl
res = context.BitwiseAnd(context.ICompareEqual(srcA, srcB), GetZF());
break;
case Decoders.IntegerCondition.Less: // r = xh < yh || (xh == yh && xl < yl)
Operand notC = context.BitwiseNot(GetCF());
Operand prevLt = context.BitwiseAnd(context.ICompareEqual(srcA, srcB), notC);
res = isSigned
? context.BitwiseOr(context.ICompareLess(srcA, srcB), prevLt)
: context.BitwiseOr(context.ICompareLessUnsigned(srcA, srcB), prevLt);
break;
case Decoders.IntegerCondition.LessOrEqual: // r = xh < yh || (xh == yh && xl <= yl)
Operand zOrNotC = context.BitwiseOr(GetZF(), context.BitwiseNot(GetCF()));
Operand prevLe = context.BitwiseAnd(context.ICompareEqual(srcA, srcB), zOrNotC);
res = isSigned
? context.BitwiseOr(context.ICompareLess(srcA, srcB), prevLe)
: context.BitwiseOr(context.ICompareLessUnsigned(srcA, srcB), prevLe);
break;
case Decoders.IntegerCondition.Greater: // r = xh > yh || (xh == yh && xl > yl)
Operand notZAndC = context.BitwiseAnd(context.BitwiseNot(GetZF()), GetCF());
Operand prevGt = context.BitwiseAnd(context.ICompareEqual(srcA, srcB), notZAndC);
res = isSigned
? context.BitwiseOr(context.ICompareGreater(srcA, srcB), prevGt)
: context.BitwiseOr(context.ICompareGreaterUnsigned(srcA, srcB), prevGt);
break;
case Decoders.IntegerCondition.GreaterOrEqual: // r = xh > yh || (xh == yh && xl >= yl)
Operand prevGe = context.BitwiseAnd(context.ICompareEqual(srcA, srcB), GetCF());
res = isSigned
? context.BitwiseOr(context.ICompareGreater(srcA, srcB), prevGe)
: context.BitwiseOr(context.ICompareGreaterUnsigned(srcA, srcB), prevGe);
break;
case Decoders.IntegerCondition.NotEqual: // r = xh != yh || xl != yl
context.BitwiseOr(context.ICompareNotEqual(srcA, srcB), context.BitwiseNot(GetZF()));
break;
default:
throw new InvalidOperationException($"Unexpected condition \"{cond}\".");
}
}
return(res);
}
