// t = b + c
// a = t
// a = b + c
private void MergeBinary()
{
for (int index = 0; index < (m_middleCodeList.Count - 1); ++index)
{
MiddleCode thisCode = m_middleCodeList[index],
nextCode = m_middleCodeList[index + 1];
if ((/*thisCode.IsUnary() ||*/ thisCode.IsBinary()) &&
(nextCode.Operator == MiddleOperator.Assign) &&
((Symbol)thisCode[0]).IsTemporary() &&
(thisCode[0] == nextCode[1]))
{
thisCode[0] = nextCode[0];
nextCode.Clear();
m_update = true;
}
}
}
private void SematicOptimization()
{
for (int index = 0; index < m_middleCodeList.Count; ++index)
{
MiddleCode thisCode = m_middleCodeList[index];
if (thisCode.IsBinary())
{
Symbol resultSymbol = (Symbol)thisCode[0],
leftSymbol = (Symbol)thisCode[1],
rightSymbol = (Symbol)thisCode[2],
newSymbol = null;
if ((leftSymbol.Value is BigInteger) && // t0 = 2 * 3
(rightSymbol.Value is BigInteger))
{
newSymbol =
ConstantExpression.ArithmeticIntegral(thisCode.Operator,
leftSymbol, rightSymbol);
}
// t0 = 0 + i
else if ((thisCode.Operator == MiddleOperator.Add) &&
(leftSymbol.Value is BigInteger) &&
(leftSymbol.Value.Equals(BigInteger.Zero)))
{
newSymbol = rightSymbol;
}
// t0 = 0 - i; t0 = -i
else if ((thisCode.Operator == MiddleOperator.Subtract) &&
(leftSymbol.Value is BigInteger) &&
(leftSymbol.Value.Equals(BigInteger.Zero)))
{
thisCode.Operator = MiddleOperator.Minus;
thisCode[0] = thisCode[1];
thisCode[1] = null;
}
// t0 = i + 0
// t0 = i - 0
else if (((thisCode.Operator == MiddleOperator.Add) ||
(thisCode.Operator == MiddleOperator.Subtract)) &&
(rightSymbol.Value is BigInteger) &&
(rightSymbol.Value.Equals(BigInteger.Zero)))
{
newSymbol = leftSymbol;
}
// t0 = 0 * i
else if ((thisCode.Operator == MiddleOperator.Multiply) &&
(leftSymbol.Value is BigInteger) &&
(leftSymbol.Value.Equals(BigInteger.Zero)))
{
newSymbol = new Symbol(resultSymbol.Type, BigInteger.Zero);
}
// t0 = 1 * i
else if ((thisCode.Operator == MiddleOperator.Multiply) &&
(leftSymbol.Value is BigInteger) &&
(leftSymbol.Value.Equals(BigInteger.One)))
{
newSymbol = rightSymbol;
}
// t0 = i * 0
else if ((thisCode.Operator == MiddleOperator.Multiply) &&
(rightSymbol.Value is BigInteger) &&
(rightSymbol.Value.Equals(BigInteger.Zero)))
{
newSymbol = new Symbol(resultSymbol.Type, BigInteger.Zero);
}
// t0 = -1 * i
else if ((thisCode.Operator == MiddleOperator.Multiply) &&
(leftSymbol.Value is BigInteger) &&
(leftSymbol.Value.Equals(BigInteger.MinusOne)))
{
thisCode.Operator = MiddleOperator.Minus;
thisCode[0] = thisCode[1];
thisCode[1] = null;
}
// t0 = i * -1
else if ((thisCode.Operator == MiddleOperator.Multiply) &&
(rightSymbol.Value is BigInteger) &&
(rightSymbol.Value.Equals(BigInteger.MinusOne)))
{
thisCode.Operator = MiddleOperator.Minus;
thisCode[1] = null;
}
// t0 = i * 1
// t0 = i / 1
// t0 = i % 1
else if (((thisCode.Operator == MiddleOperator.Multiply) ||
(thisCode.Operator == MiddleOperator.Divide) ||
(thisCode.Operator == MiddleOperator.Modulo)) &&
(rightSymbol.Value is BigInteger) &&
(rightSymbol.Value.Equals(BigInteger.One)))
{
newSymbol = leftSymbol;
}
if (newSymbol != null)
{
if (resultSymbol.IsTemporary())
{
thisCode.Operator = MiddleOperator.Empty;
if (newSymbol.IsTemporary())
{
int index2;
for (index2 = (index - 1); index2 >= 0; --index2)
{
MiddleCode previousCode = m_middleCodeList[index2];
if (previousCode[0] == resultSymbol)
{
previousCode[0] = newSymbol;
break;
}
}
}
{ int index2;
for (index2 = index + 1; index2 < m_middleCodeList.Count;
++index2)
{
MiddleCode nextCode = m_middleCodeList[index2];
if (nextCode[0] == resultSymbol)
{
nextCode[0] = newSymbol;
}
if (nextCode[1] == resultSymbol)
{
nextCode[1] = newSymbol;
}
if (nextCode[2] == resultSymbol)
{
nextCode[2] = newSymbol;
}
}
}
}
else
{
thisCode.Operator = MiddleOperator.Assign; // i = 0 + j;
thisCode[1] = newSymbol; // i = j;
thisCode[2] = null;
}
m_update = true;
}
}
}
}