public VarInfo Merge(VarInfo other)
{
if (other.Type == Type)
{
if (other.Value != Value)
{
return(new VarInfo(Flag.NAC));
}
return(this);
}
if (IsUndef && other.IsConst)
{
return(other.Copy());
}
if (IsUndef && other.IsNac)
{
return(other.Copy());
}
if (IsNac)
{
return(this.Copy());
}
if (other.IsNac)
{
return(other.Copy());
}
return(this.Copy());
}
public int?Compare(VarInfo other)
{
if (Type == other.Type)
{
if (Type == Flag.Const)
{
if (Value == other.Value)
{
return(0);
}
else
{
return(null);
}
}
return(0);
}
if (Type == Flag.UNDEF)
{
return(1);
}
if (Type == Flag.NAC)
{
return(-1);
}
if (other.Type == Flag.NAC)
{
return(1);
}
return(-1);
}
public VarInfoTable Transfer(BasicBlock basicBlock, VarInfoTable input, ILatticeOperations <VarInfoTable> ops)
{
var table = input.Copy();
VarInfo Get(Expr e)
{
if (e is IntConst c)
{
return(new VarInfo(VarInfo.Flag.Const, c.Num));
}
if (e is Var v)
{
return(table[v.Id].Copy());
}
return(new VarInfo(VarInfo.Flag.NAC));
}
foreach (var line in basicBlock.CodeList.OfType <Assign>())
{
if (line.Left is null)
{
table[line.Result.Id] = Get(line.Right);
}
else
{
var vi1 = Get(line.Right);
var vi2 = Get(line.Left);
table[line.Result.Id] = VarInfo.MergeBin(vi1, vi2, line.Operation);
}
}
return(table);
}
public static VarInfo MergeBin(VarInfo vi1, VarInfo vi2, OpCode?op)
{
if (vi1.IsConst && vi2.IsConst)
{
Func <int, int, int> f = (x, y) => x + y;
if (op == OpCode.Div)
{
f = (x, y) => x / y;
}
if (op == OpCode.Equal)
{
f = (x, y) => x == y ? 1 : 0;
}
if (op == OpCode.Greater)
{
f = (x, y) => x > y ? 1 : 0;
}
if (op == OpCode.GreaterEq)
{
f = (x, y) => x >= y ? 1 : 0;
}
if (op == OpCode.Less)
{
f = (x, y) => x < y ? 1 : 0;
}
if (op == OpCode.LessEq)
{
f = (x, y) => x <= y ? 1 : 0;
}
if (op == OpCode.Minus)
{
f = (x, y) => x - y;
}
if (op == OpCode.Mul)
{
f = (x, y) => x * y;
}
if (op == OpCode.Plus)
{
f = (x, y) => x + y;
}
return(new VarInfo(Flag.Const, f(vi1.Value.Value, vi2.Value.Value)));
}
if (vi1.IsNac || vi2.IsNac)
{
return(new VarInfo(Flag.NAC));
}
return(new VarInfo(Flag.UNDEF));
}
public Operations(TACode code)
{
Lower = new VarInfoTable(code);
var keys = Lower.Keys.ToArray();
foreach (var k in keys)
{
Lower[k] = new VarInfo(VarInfo.Flag.NAC);
}
Upper = new VarInfoTable(code);
foreach (var k in keys)
{
Upper[k] = new VarInfo(VarInfo.Flag.UNDEF);
}
}