void VisitLogicNot(Comp inst, ILInstruction arg)
{
ILInstruction lhs, rhs;
if (arg is Comp comp)
{
if ((comp.InputType != StackType.F && !comp.IsLifted) || comp.Kind.IsEqualityOrInequality())
{
context.Step("push negation into comparison", inst);
comp.Kind = comp.Kind.Negate();
comp.AddILRange(inst.ILRange);
inst.ReplaceWith(comp);
}
comp.AcceptVisitor(this);
}
else if (arg.MatchLogicAnd(out lhs, out rhs))
{
// logic.not(if (lhs) rhs else ldc.i4 0)
// ==> if (logic.not(lhs)) ldc.i4 1 else logic.not(rhs)
context.Step("push negation into logic.and", inst);
IfInstruction ifInst = (IfInstruction)arg;
var ldc0 = ifInst.FalseInst;
Debug.Assert(ldc0.MatchLdcI4(0));
ifInst.Condition = Comp.LogicNot(lhs, inst.ILRange);
ifInst.TrueInst = new LdcI4(1)
{
ILRange = ldc0.ILRange
};
ifInst.FalseInst = Comp.LogicNot(rhs, inst.ILRange);
inst.ReplaceWith(ifInst);
ifInst.AcceptVisitor(this);
}
else if (arg.MatchLogicOr(out lhs, out rhs))
{
// logic.not(if (lhs) ldc.i4 1 else rhs)
// ==> if (logic.not(lhs)) logic.not(rhs) else ldc.i4 0)
context.Step("push negation into logic.or", inst);
IfInstruction ifInst = (IfInstruction)arg;
var ldc1 = ifInst.TrueInst;
Debug.Assert(ldc1.MatchLdcI4(1));
ifInst.Condition = Comp.LogicNot(lhs, inst.ILRange);
ifInst.TrueInst = Comp.LogicNot(rhs, inst.ILRange);
ifInst.FalseInst = new LdcI4(0)
{
ILRange = ldc1.ILRange
};
inst.ReplaceWith(ifInst);
ifInst.AcceptVisitor(this);
}
else
{
arg.AcceptVisitor(this);
}
}
