private void Call(CodeFunctor codeFunctor, LibraryList libraries)
{
Functor functor = Functor.Create(codeFunctor);
if (functor == Functor.CutFunctor)
{
InstructionStreamBuilder.Write(new WamInstruction(WamInstructionOpCodes.Cut));
}
else if (libraries.Contains(functor))
{
InstructionStreamBuilder.Write(new WamInstruction(WamInstructionOpCodes.LibraryCall, functor));
}
else
{
InstructionStreamBuilder.Write(new WamInstruction(WamInstructionOpCodes.Call, functor));
}
}
public WamInstructionStream Compile(CodeSentence codeSentence, LibraryList libraries, bool optimize)
{
return(Compile(codeSentence, null, -1, false, libraries, optimize));
}
public WamInstructionStream Compile(CodeSentence codeSentence, Functor functor, int index, bool isLast, LibraryList libraries, bool optimize)
{
Initialize();
// When true, indicates we are compiling code for a procedure clause. When false, indicates we
// are compiling for an ad hoc query.
//
bool isClause = (functor != null);
if (isClause)
{
WamInstructionStreamClauseAttribute clauseAttribute = new WamInstructionStreamClauseAttribute(
m_instructionStreamBuilder.NextIndex,
functor,
index);
m_instructionStreamBuilder.AddAttribute(clauseAttribute);
}
if (isClause)
{
if (isLast)
{
if (index == 0)
{
// Procedure only has one clause in it. No retry logic required.
}
else
{
TrustMe();
}
}
else
{
if (index == 0)
{
TryMeElse(functor, index + 1);
}
else
{
RetryMeElse(functor, index + 1);
}
}
}
Allocate();
if (codeSentence.Head != null)
{
for (int idx = 0; idx < codeSentence.Head.Children.Count; ++idx)
{
Get(codeSentence.Head.Children[idx], GetArgumentRegister(idx));
}
}
if (codeSentence.Body.Count > 0)
{
for (int idxProcedure = 0; idxProcedure < codeSentence.Body.Count; ++idxProcedure)
{
CodeCompoundTerm codeCompoundTerm = codeSentence.Body[idxProcedure];
for (int idxArgument = 0; idxArgument < codeCompoundTerm.Children.Count; ++idxArgument)
{
Put(codeCompoundTerm.Children[idxArgument], GetArgumentRegister(idxArgument), libraries);
}
bool isLastCall = (idxProcedure == codeSentence.Body.Count - 1);
if (isClause)
{
if (isLastCall)
{
if (optimize &&
!libraries.Contains(Functor.Create(codeCompoundTerm.Functor)) &&
codeCompoundTerm.Functor != CodeFunctor.CutFunctor)
{
Deallocate();
Execute(codeCompoundTerm.Functor);
}
else
{
Call(codeCompoundTerm.Functor, libraries);
Deallocate();
Proceed();
}
}
else
{
Call(codeCompoundTerm.Functor, libraries);
}
}
else // isQuery
{
Call(codeCompoundTerm.Functor, libraries);
if (isLastCall)
{
Success();
}
}
}
}
else // fact
{
if (isClause)
{
Deallocate();
Proceed();
}
else // isQuery
{
// No action required.
}
}
return(InstructionStreamBuilder.ToInstructionStream());
}
private void Put(CodeCompoundTerm codeCompoundTerm, WamInstructionRegister targetRegister, LibraryList libraries)
{
WamInstructionRegister[] childrenRegisters = new WamInstructionRegister[codeCompoundTerm.Children.Count];
// Build substructures.
//
for (int idx = 0; idx < codeCompoundTerm.Children.Count; ++idx)
{
CodeTerm child = codeCompoundTerm.Children[idx];
if (child.IsCodeList)
{
child = ConvertCodeList(child.AsCodeList);
}
if (child.IsCodeCompoundTerm)
{
childrenRegisters[idx] = GetNextTemporaryRegister();
Put(child, childrenRegisters[idx], libraries);
}
}
Functor functor = Functor.Create(codeCompoundTerm.Functor);
InstructionStreamBuilder.Write(new WamInstruction(WamInstructionOpCodes.PutStructure, functor, targetRegister));
for (int idx = 0; idx < codeCompoundTerm.Children.Count; ++idx)
{
CodeTerm child = codeCompoundTerm.Children[idx];
if (child.IsCodeList)
{
child = ConvertCodeList(child.AsCodeList);
}
if (child.IsCodeVariable)
{
string variableName = child.AsCodeVariable.Name;
WamInstructionRegister variableRegister = GetRegisterAssignment(variableName);
if (variableRegister.IsUnused)
{
variableRegister = GetNextPermanentRegister(variableName);
InstructionStreamBuilder.Write(new WamInstruction(WamInstructionOpCodes.SetUnboundVariable, variableRegister));
}
else
{
InstructionStreamBuilder.Write(new WamInstruction(WamInstructionOpCodes.SetBoundVariable, variableRegister));
}
}
else if (child.IsCodeCompoundTerm)
{
InstructionStreamBuilder.Write(new WamInstruction(WamInstructionOpCodes.SetBoundVariable, childrenRegisters[idx]));
}
else if (child.IsCodeValue)
{
InstructionStreamBuilder.Write(new WamInstruction(WamInstructionOpCodes.SetValue, WamValue.Create(child.AsCodeValue)));
}
else
{
throw new InvalidOperationException("Unsupported codeTerm type.");
}
}
}