private static void CgFuncCallStat(FuncInfo fi, FuncCallStat node)
{
var r = fi.AllocReg();
CgFuncCallExp(fi, node, r, 0);
fi.FreeReg();
}
private static void CgUnopExp(FuncInfo fi, UnopExp node, int a)
{
var b = fi.AllocReg();
CgExp(fi, node.Exp, b, 1);
fi.EmitUnaryOp(node.GetOpCode(), a, b);
fi.FreeReg();
}
private static void CgBinopExp(FuncInfo fi, BinopExp node, int a)
{
switch (node.Op)
{
case ETokenType.OpAnd:
case ETokenType.OpOr:
{
var b = fi.AllocReg();
CgExp(fi, node.Exp1, b, 1);
fi.FreeReg();
if (node.Op == ETokenType.OpAnd)
{
fi.EmitTestSet(a, b, 0);
}
else
{
fi.EmitTestSet(a, b, 1);
}
var pcOfJmp = fi.EmitJmp(0, 0);
b = fi.AllocReg();
CgExp(fi, node.Exp2, b, 1);
fi.FreeReg();
fi.EmitMove(a, b);
fi.FixsBx(pcOfJmp, fi.PC() - pcOfJmp);
break;
}
default:
{
var b = fi.AllocReg();
CgExp(fi, node.Exp1, b, 1);
var c = fi.AllocReg();
CgExp(fi, node.Exp2, c, 1);
fi.EmitBinaryOp(node.Op, a, b, c);
fi.FreeRegs(2);
break;
}
}
}
private static void CgRepeatStat(FuncInfo fi, RepeatStat node)
{
fi.EnterScope(true);
var pcBeforeBlock = fi.PC();
CgBlock(fi, node.Block);
var r = fi.AllocReg();
CgExp(fi, node.Exp, r, 1);
fi.FreeReg();
fi.EmitTest(r, 0);
fi.EmitJmp(fi.GetJmpArgA(), pcBeforeBlock - fi.PC() - 1);
fi.CloseOpenUpvals();
fi.ExitScope();
}
private static void CgWhileStat(FuncInfo fi, WhileStat node)
{
var pcBeforeExp = fi.PC();
var r = fi.AllocReg();
CgExp(fi, node.Exp, r, 1);
fi.FreeReg();
fi.EmitTest(r, 0);
var pcJmpToEnd = fi.EmitJmp(0, 0);
fi.EnterScope(true);
CgBlock(fi, node.Block);
fi.CloseOpenUpvals();
fi.EmitJmp(0, pcBeforeExp - fi.PC() - 1);
fi.ExitScope();
fi.FixsBx(pcJmpToEnd, fi.PC() - pcJmpToEnd);
}
private static void CgIfStat(FuncInfo fi, IfStat node)
{
var pcJmpToEnds = new int[node.Exps.Count];
var pcJmpToNextExp = -1;
for (var i = 0; i < node.Exps.Count; i++)
{
var exp = node.Exps[i];
if (pcJmpToNextExp >= 0)
{
fi.FixsBx(pcJmpToNextExp, fi.PC() - pcJmpToNextExp);
}
var r = fi.AllocReg();
CgExp(fi, exp, r, 1);
fi.FreeReg();
fi.EmitTest(r, 0);
pcJmpToNextExp = fi.EmitJmp(0, 0);
fi.EnterScope(false);
CgBlock(fi, node.Blocks[i]);
fi.CloseOpenUpvals();
fi.ExitScope();
if (i < node.Exps.Count - 1)
{
pcJmpToEnds[i] = fi.EmitJmp(0, 0);
}
else
{
pcJmpToEnds[i] = pcJmpToNextExp;
}
}
foreach (var pc in pcJmpToEnds)
{
fi.FixsBx(pc, fi.PC() - pc);
}
}
private static void CgRetStat(FuncInfo fi, List <Exp> exps)
{
var nExps = exps.Count;
if (nExps == 0)
{
fi.EmitReturn(0, 0);
return;
}
if (nExps == 1)
{
if (exps[0] is NameExp nameExp)
{
var r = fi.SlotOfLocVar(nameExp.Name);
if (r >= 0)
{
fi.EmitReturn(r, 1);
return;
}
}
if (exps[0] is FuncCallExp fcExp)
{
var r = fi.AllocReg();
CgTailCallExp(fi, fcExp, r);
fi.FreeReg();
fi.EmitReturn(r, -1);
return;
}
}
var multRet = IsVarargOrFuncCall(exps[nExps - 1]);
for (var i = 0; i < nExps; i++)
{
var exp = exps[i];
var r = fi.AllocReg();
if (i == nExps - 1 && multRet)
{
CgExp(fi, exp, r, -1);
}
else
{
CgExp(fi, exp, r, 1);
}
}
fi.FreeRegs(nExps);
var a = fi.UsedRegs;
if (multRet)
{
fi.EmitReturn(a, -1);
}
else
{
fi.EmitReturn(a, nExps);
}
}
