private void CGUnaryExp(FuncInfo funcInfo, UnaryExpNode node, int a)
{
int b = funcInfo.AllocReg();
CGExp(funcInfo, node.Exp, b, 1);
funcInfo.EmitUnaryOp(a, b, node.OpType);
funcInfo.FreeReg();
}
private void CGBinOpExp(FuncInfo funcInfo, DoubleOperationExpNode node, int a)
{
switch (node.OpType)
{
case TokenType.And:
case TokenType.Or:
{
int b = funcInfo.AllocReg();
CGExp(funcInfo, node.Exp1, b, 1);
funcInfo.FreeReg();
if (node.OpType == TokenType.And)
{
funcInfo.EmitTestSet(a, b, 0);
}
else
{
funcInfo.EmitTestSet(a, b, 1);
}
int jmpPC = funcInfo.EmitJMP(0, 0);
int c = funcInfo.AllocReg();
CGExp(funcInfo, node.Exp2, c, 1);
funcInfo.FreeReg();
funcInfo.EmitMove(a, c);
funcInfo.FixSBX(jmpPC, funcInfo.PC() - jmpPC);
break;
}
default:
{
int b = funcInfo.AllocReg();
CGExp(funcInfo, node.Exp1, b, 1);
int c = funcInfo.AllocReg();
CGExp(funcInfo, node.Exp2, c, 1);
funcInfo.EmitDoubleOperator(a, b, c, node.OpType);
funcInfo.FreeRegs(2);
break;
}
}
}
private void CGRepeatStat(FuncInfo funcInfo, RepeatStatNode node)
{
funcInfo.EnterScope(true);
int blockPC = funcInfo.PC();
CGBlock(funcInfo, node.Block);
int r = funcInfo.AllocReg();
CGExp(funcInfo, node.Exp, r, 1);
funcInfo.FreeReg();
funcInfo.EmitTest(r, 0);
funcInfo.EmitJMP(0, blockPC - funcInfo.PC() - 1);
funcInfo.ExitScope();
}
private void CGWhileStat(FuncInfo funcInfo, WhileStatNode node)
{
int beforePc = funcInfo.PC();
int r = funcInfo.AllocReg();
CGExp(funcInfo, node.Exp, r, 1);
funcInfo.FreeReg();
funcInfo.EmitTest(r, 0);
int jumPC = funcInfo.EmitJMP(0, 0);
funcInfo.EnterScope(true);
CGBlock(funcInfo, node.DoStatNode.Block);
funcInfo.EmitJMP(0, beforePc - funcInfo.PC());
funcInfo.ExitScope();
funcInfo.FixSBX(jumPC, funcInfo.PC() - jumPC);
}
private void CGIfStat(FuncInfo funcInfo, IfStatNode node)
{
var jmpToEndsPC = new int[node.Exp.Count];
int jmpToNextExpPc = -1;
int i = 0;
foreach (var exp in node.Exp)
{
if (jmpToNextExpPc > 0)
{
funcInfo.FixSBX(jmpToNextExpPc, funcInfo.PC() - jmpToNextExpPc);
}
int r = funcInfo.AllocReg();
CGExp(funcInfo, exp, r, 1);
funcInfo.FreeReg();
funcInfo.EmitTest(r, 0);
jmpToNextExpPc = funcInfo.EmitJMP(0, 0);
funcInfo.EnterScope(false);
CGBlock(funcInfo, node.Block);
funcInfo.ExitScope();
if (i < node.Exp.Count - 1)
{
jmpToEndsPC[i] = funcInfo.EmitJMP(0, 0);
}
else
{
jmpToEndsPC[i] = jmpToNextExpPc;
}
i++;
}
foreach (int j in jmpToEndsPC)
{
funcInfo.FixSBX(j, funcInfo.PC() - j);
}
}
