private static void CgForNumStat(FuncInfo fi, ForNumStat node)
{
fi.EnterScope(true);
CgLocalVarDeclStat(fi, new LocalVarDeclStat
{
NameList = new List <string> {
"(for index)", "(for limit)", "(for step)"
},
ExpList = new List <Exp> {
node.InitExp, node.LimitExp, node.StepExp
}
});
fi.AddLocVar(node.VarName);
var a = fi.UsedRegs - 4;
var pcForPrep = fi.EmitForPrep(a, 0);
CgBlock(fi, node.Block);
fi.CloseOpenUpvals();
var pcForLoop = fi.EmitForLoop(a, 0);
fi.FixsBx(pcForPrep, pcForLoop - pcForPrep - 1);
fi.FixsBx(pcForLoop, pcForPrep - pcForLoop);
fi.ExitScope();
}
private static void CgForInStat(FuncInfo fi, ForInStat node)
{
fi.EnterScope(true);
CgLocalVarDeclStat(fi, new LocalVarDeclStat
{
NameList = new List <string> {
"(for generator)", "(for state)", "(for control)"
},
ExpList = node.ExpList
});
foreach (var name in node.NameList)
{
fi.AddLocVar(name);
}
var pcJmpToTfc = fi.EmitJmp(0, 0);
CgBlock(fi, node.Block);
fi.CloseOpenUpvals();
fi.FixsBx(pcJmpToTfc, fi.PC() - pcJmpToTfc);
var rGenerator = fi.SlotOfLocVar("(for generator)");
fi.EmitTForCall(rGenerator, node.NameList.Count);
fi.EmitTForLoop(rGenerator + 2, pcJmpToTfc - fi.PC() - 1);
fi.ExitScope();
}
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 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 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);
}
