private Result OnFetchReturn()
{
var retn = _node.As <ReturnNode>();
_variableContext.ReturningList.Add(retn);
if (_functionDeclaration.ReturnCount != 0)
{
var ret = _functionDeclaration.GetReturn(0);
var retClass = ret.VariableType.GetRegisterClass();
_variableContext.Begin();
for (var i = 0; i < 2; i++)
{
var op = retn.Operands[i];
if (!op.IsVariable())
{
continue;
}
var vd = _compiler.GetVariableData(op.Id);
var va = _variableContext.Merge(vd, 0, 0);
if (retClass == vd.Info.RegisterClass)
{
// TODO: [COMPILER] Fix HLRet fetch.
va.Flags |= VariableFlags.RReg;
va.InRegs = i == 0 ? Utils.Mask(RegisterIndex.Ax) : Utils.Mask(RegisterIndex.Dx);
_variableContext.InRegs.Or(retClass, va.InRegs);
}
else if (retClass == RegisterClass.Fp)
{
var fldFlag = ret.VariableType == VariableType.Fp32 ? VariableFlags.X86Fld4 : VariableFlags.X86Fld8;
va.Flags |= VariableFlags.RMem | fldFlag;
}
else
{
// TODO: Fix possible other return type conversions.
}
}
_variableContext.End(_node);
}
if (_next.IsFetched())
{
return(Result.Break);
}
_unreachableList.Add(_next);
return(Result.NextGroup);
}
private Result GoTo(bool @do)
{
if (!@do || _node.IsFetched())
{
if (_jLinkIndex == -1)
{
_jLinkIndex = 0;
}
else
{
_jLinkIndex++;
}
if (_jLinkIndex >= _variableContext.JccList.Count)
{
_node = null;
return(Result.Done);
}
_node = GetOppositeJccFlow(_variableContext.JccList[_jLinkIndex].As <JumpNode>());
}
return(Result.Break);
}
internal VariableContext Run()
{
var flowId = 0;
_next = null;
_node = _functionNode;
var result = Result.Do;
do
{
if (result == Result.Done)
{
break;
}
if (GoTo(@do: result != Result.NextGroup) == Result.Done)
{
break;
}
flowId++;
_next = _node.Next;
_node.FlowId = flowId;
switch (_node.Type)
{
case CodeNodeType.None:
case CodeNodeType.Data:
case CodeNodeType.Alignment:
case CodeNodeType.Comment:
case CodeNodeType.CallArgument:
break;
case CodeNodeType.Label:
result = OnFetchLabel();
break;
case CodeNodeType.Sentinel:
result = OnFetchSentinel();
break;
case CodeNodeType.Instruction:
result = OnFetchInstruction();
break;
case CodeNodeType.Hint:
result = OnFetchHint();
break;
case CodeNodeType.Function:
result = OnFetchFunction();
break;
case CodeNodeType.Return:
result = OnFetchReturn();
break;
case CodeNodeType.Call:
result = OnFetchCall();
break;
default:
throw new ArgumentOutOfRangeException();
}
if (result == Result.Do || result == Result.NextGroup || result == Result.Done)
{
continue;
}
_node = _next;
} while (_node != _stopNode);
// Mark exit label and end node as fetched, otherwise they can be removed by
// `removeUnreachableCode()`, which would lead to crash in some later step.
_node = _functionNode.End;
if (_node.IsFetched())
{
RemoveUnreachableCode();
return(_variableContext);
}
_functionNode.Exit.FlowId = ++flowId;
_node.FlowId = ++flowId;
RemoveUnreachableCode();
return(_variableContext);
}