//因子
private void Factor()
{
LexicalAnalysisResult lex = (LexicalAnalysisResult)Lexresult[i];
if (lex.Type == LexicalAnalysis.IDSY)
{
//检查标识符存不存在
//没检查同层但是不同过程的相关声明，需要在符号表栈中标记
int preloc = -1;
for (int ind = symbols.Count - 1; ind >= 0; ind--)
{
Symbols tempsym = (Symbols)symbols[ind];
if (lex.Content.Equals(tempsym.Name) && level >= tempsym.Level)
{
preloc = ind;
break;
}
}
if (preloc == -1)
{
flag = false;
Console.WriteLine("错误：不存在符号{0}", lex.Content);
String msg = "错误：不存在符号" + lex.Content;
errors.Add(new Error(msg, lex.Line));
return;
}
//PCODE 标识符相关
PCodes.Add(new PCode(codeAddr, PCode.INT, 0, 1));
codeAddr++;
Symbols sym_t = (Symbols)symbols[preloc];
int sym_lev = sym_t.Level;
PCodes.Add(new PCode(codeAddr, PCode.LOD, level - sym_lev, sym_t.Addr));
codeAddr++;
i++;
return;
}
else if (lex.Type == LexicalAnalysis.INTSY)
{
int Num = Convert.ToInt32(lex.Content);
//PCODE 数字相关
PCodes.Add(new PCode(codeAddr, PCode.INT, 0, 1));
codeAddr++;
PCodes.Add(new PCode(codeAddr, PCode.LIT, 0, Num));
codeAddr++;
i++;
return;
}
else if (lex.Type == LexicalAnalysis.LPARSY)
{
i++;
ExpressionCode();
//i++
lex = (LexicalAnalysisResult)Lexresult[i];
if (lex.Type != LexicalAnalysis.RPARSY)
{
flag = false;
Console.WriteLine("错误：此处应为 ( ");
errors.Add(new Error("错误：此处应为 ( ", lex.Line));
return;
}
else
{
//P-CODE
i++;
return;
}
}
else
{
flag = false;
Console.WriteLine("错误：缺少标识符、数字或(");
errors.Add(new Error("错误：缺少标识符、数字或(", lex.Line));
return;
}
}
//赋值语句
private void AssignCode()
{
LexicalAnalysisResult lex = (LexicalAnalysisResult)Lexresult[i];
if (lex.Type != LexicalAnalysis.IDSY)
{
flag = false;
Console.WriteLine("错误：赋值语句无标识符");
errors.Add(new Error("错误：其他错误", lex.Line));
return;
}
//符号表检查
int preloc = -1;
//之前的同一层符号表还没有检查
for (int ind = symbols.Count - 1; ind >= 0; ind--)
{
Symbols tempsym = (Symbols)symbols[ind];
if (lex.Content.Equals(tempsym.Name) && level >= tempsym.Level)
{
preloc = ind;
break;
}
}
if (preloc == -1)
{
flag = false;
Console.WriteLine("错误：不存在符号{0}", lex.Content);
errors.Add(new Error("错误：不存在符号" + lex.Content, lex.Line));
return;
}
//PCODE 标识符相关
PCodes.Add(new PCode(codeAddr, PCode.INT, 0, 1));
codeAddr++;
Symbols sym_t = (Symbols)symbols[preloc];
int sym_lev = sym_t.Level;
PCodes.Add(new PCode(codeAddr, PCode.LOD, level - sym_lev, sym_t.Addr));
codeAddr++;
//表达式检查
i++;
lex = (LexicalAnalysisResult)Lexresult[i];
if (lex.Type != LexicalAnalysis.ASSIGNSY)
{
flag = false;
Console.WriteLine("错误：此处应为赋值符号");
errors.Add(new Error("错误：应为赋值符号 :=", lex.Line));
return;
}
i++;
//进入表达式判断
ExpressionCode();
if (flag == true)
{
//PCODE
PCodes.Add(new PCode(codeAddr, PCode.STO, level - sym_lev, sym_t.Addr));
codeAddr++;
return;
}
else
{
Console.WriteLine("Error!");
errors.Add(new Error("错误：其他错误。", 0));
return;
}
}
//过程说明部分
private void ProcIndicate()
{
//JMP 0 主程序入口
PCodes.Add(new PCode(codeAddr, PCode.JMP, 0, 0));
int bufcodeaddr = codeAddr;
//JMP此处的0表示待定
codeAddr++;
LexicalAnalysisResult lex = (LexicalAnalysisResult)Lexresult[i];
//标识符
if (lex.Type != LexicalAnalysis.IDSY)
{
flag = false;
Console.WriteLine("错误：procedure后应为标识符");
errors.Add(new Error("错误：procedure后应为标识符", lex.Line));
return;
}
Symbols sym = new Symbols();
sym.Name = lex.Content;
sym.Type = (int)Symbols.SymTypes.PROC;
sym.Level = level;
sym.Value = codeAddr + 1;
sym.Addr = addr[level];
addr[level]++;
//;
PCodes.Add(new PCode(codeAddr, PCode.JMP, 0, codeAddr + 1));
codeAddr++;
i++;
lex = (LexicalAnalysisResult)Lexresult[i];
if (lex.Type != LexicalAnalysis.SEMISY)
{
flag = false;
Console.WriteLine("缺少 ;");
errors.Add(new Error("错误：缺少 ;", lex.Line));
return;
}
for (int i = symbols.Count - 1; i >= 0; i--)
{
Symbols tempsym = (Symbols)symbols[i];
if (tempsym.Name.Equals(sym.Name) && level == tempsym.Level)
{
flag = false;
Console.WriteLine("错误：符号表已存在标识符" + sym.Name);
errors.Add(new Error("错误：符号表已存在标识符" + sym.Name, lex.Line));
return;
}
}
symbols.Add(sym);
i++;
level++;
if (level > 10)
{
flag = false;
errors.Add(new Error("错误：分程序层次过多", lex.Line));
return;
}
Program();
//符号表删除
int cnt = symbols.Count - 1;
for (int i = cnt; i >= 0; i--)
{
Symbols sym_prerem = (Symbols)symbols[i];
if (sym_prerem.Level == level)
{
symbols.RemoveAt(i);
}
}
level--;
//i++;
lex = (LexicalAnalysisResult)Lexresult[i];
if (lex.Type != LexicalAnalysis.SEMISY)
{
flag = false;
Console.WriteLine("缺少 ;");
errors.Add(new Error("错误：缺少 ;", lex.Line));
return;
}
i++;
PCode pc = (PCode)PCodes[bufcodeaddr];
pc.Y = codeAddr;
PCodes.Add(new PCode(codeAddr, PCode.OPR, 0, 0));
codeAddr++;
lex = (LexicalAnalysisResult)Lexresult[i];
if (lex.Type == LexicalAnalysis.PROCEDURE)
{
i++;
ProcIndicate();
}
else
{
//i++;
return;
}
}
//变量说明部分
private void VarIndicate()
{
LexicalAnalysisResult lex = (LexicalAnalysisResult)Lexresult[i];
if (lex.Type != LexicalAnalysis.IDSY)
{
flag = false;
Console.WriteLine("错误：var后面应为标识符");
errors.Add(new Error("错误：var后面应为标识符", lex.Line));
return;
}
Symbols sym = new Symbols();
sym.Type = (int)Symbols.SymTypes.VAR;
sym.Name = lex.Content;
sym.Level = level;
sym.Addr = addr[level];
addr[level]++;
i++;
lex = (LexicalAnalysisResult)Lexresult[i];
if (lex.Type == LexicalAnalysis.COMMASY)
{
for (int i = symbols.Count - 1; i >= 0; i--)
{
Symbols tempsym = (Symbols)symbols[i];
if (tempsym.Name.Equals(sym.Name) && level == tempsym.Level)
{
flag = false;
Console.WriteLine("错误：符号表已存在标识符" + sym.Name);
errors.Add(new Error("错误：符号表已存在标识符" + sym.Name, lex.Line));
return;
}
}
symbols.Add(sym);
i++;
VarIndicate();
}
else if (lex.Type == LexicalAnalysis.SEMISY)
{
for (int i = symbols.Count - 1; i >= 0; i--)
{
Symbols tempsym = (Symbols)symbols[i];
if (tempsym.Name.Equals(sym.Name) && level == tempsym.Level)
{
flag = false;
Console.WriteLine("错误：符号表已存在标识符" + sym.Name);
errors.Add(new Error("错误：符号表已存在标识符" + sym.Name, lex.Line));
return;
}
}
symbols.Add(sym);
i++;
return;
}
else
{
flag = false;
Console.WriteLine("错误：符号应为 , 或 ;");
errors.Add(new Error("错误：符号应为 , 或 ;", lex.Line));
return;
}
}
//常量说明部分
private void ConstIndicate()
{
if (i >= Lexresult.Count)
{
flag = false;
Console.WriteLine("错误：程序没有语句！");
errors.Add(new Error("错误：程序没有语句。", 0));
return;
}
LexicalAnalysisResult lex = (LexicalAnalysisResult)Lexresult[i];
//常量定义
if (lex.Type != LexicalAnalysis.IDSY)
{
flag = false;
Console.WriteLine("错误：常量const后无标识符");
errors.Add(new Error("错误：常量const后无标识符", lex.Line));
return;
}
else
{
Symbols sym = new Symbols();
sym.Type = (int)Symbols.SymTypes.CONST;
sym.Level = 0;
sym.Addr = 0;
sym.Name = lex.Content;
//addr[level]++;
i++;
lex = (LexicalAnalysisResult)Lexresult[i];
if (lex.Type != LexicalAnalysis.EQUSY)
{
flag = false;
Console.WriteLine("错误：const标识符后无=符号");
errors.Add(new Error("错误：const标识符后无=符号", lex.Line));
return;
}
i++;
lex = (LexicalAnalysisResult)Lexresult[i];
if (lex.Type != LexicalAnalysis.INTSY)
{
flag = false;
Console.WriteLine("错误：常量标识符赋值应为无符号整数");
errors.Add(new Error("错误：常量标识符赋值应为无符号整数", lex.Line));
return;
}
if (Convert.ToInt64(lex.Content) > Convert.ToInt64(Int32.MaxValue))
{
flag = false;
Console.WriteLine("错误：整数太大");
errors.Add(new Error("错误：整数太大", lex.Line));
return;
}
sym.Value = Convert.ToInt32(lex.Content);
for (int i = symbols.Count - 1; i >= 0; i--)
{
Symbols tempsym = (Symbols)symbols[i];
if (tempsym.Name.Equals(sym.Name) && level == tempsym.Level)
{
flag = false;
Console.WriteLine("错误：符号表已存在标识符" + sym.Name);
errors.Add(new Error("错误：符号表已存在标识符" + sym.Name, lex.Line));
return;
}
}
symbols.Add(sym);
//递归子程序或结束
i++;
lex = (LexicalAnalysisResult)Lexresult[i];
if (lex.Type == LexicalAnalysis.SEMISY)
{
i++;
return;
}
else if (lex.Type == LexicalAnalysis.COMMASY)
{
i++;
ConstIndicate();
}
else
{
flag = false;
Console.WriteLine("错误：符号应为 , 或 ;");
errors.Add(new Error("错误：符号应为 , 或 ;", lex.Line));
return;
}
}
}
//写语句
private void WriteCode()
{
LexicalAnalysisResult lex = (LexicalAnalysisResult)Lexresult[i];
if (lex.Type != LexicalAnalysis.WRITESY)
{
flag = false;
Console.WriteLine("Error!");
errors.Add(new Error("错误：其他错误。", 0));
return;
}
i++;
lex = (LexicalAnalysisResult)Lexresult[i];
if (lex.Type != LexicalAnalysis.LPARSY)
{
flag = false;
Console.WriteLine("错误：此处应为(");
errors.Add(new Error("错误：此处应补充(", lex.Line));
return;
}
i++;
lex = (LexicalAnalysisResult)Lexresult[i];
if (lex.Type == LexicalAnalysis.IDSY)
{
//PCODE?
//检查符号表
int preloc = -1;
for (int ind = symbols.Count - 1; ind >= 0; ind--)
{
Symbols tempsym = (Symbols)symbols[ind];
if (lex.Content.Equals(tempsym.Name) && level >= tempsym.Level)
{
preloc = ind;
break;
}
}
if (preloc == -1)
{
flag = false;
Console.WriteLine("错误：不存在符号{0}", lex.Content);
errors.Add(new Error("错误：不存在符号" + lex.Content, lex.Line));
return;
}
Symbols sym = (Symbols)symbols[preloc];
PCodes.Add(new PCode(codeAddr, PCode.INT, 0, 1));
codeAddr++;
PCodes.Add(new PCode(codeAddr, PCode.LOD, level - sym.Level, sym.Addr));
codeAddr++;
PCodes.Add(new PCode(codeAddr, PCode.WRT, 0, 0));
codeAddr++;
i++;
}
else if (lex.Type == LexicalAnalysis.INTSY)
{
PCodes.Add(new PCode(codeAddr, PCode.INT, 0, 1));
codeAddr++;
PCodes.Add(new PCode(codeAddr, PCode.LIT, 0, Convert.ToInt32(lex.Content)));
codeAddr++;
PCodes.Add(new PCode(codeAddr, PCode.WRT, 0, 0));
codeAddr++;
i++;
}
else
{
flag = false;
Console.WriteLine("无标识符");
errors.Add(new Error("错误：无标识符", lex.Line));
return;
}
lex = (LexicalAnalysisResult)Lexresult[i];
while (lex.Type == LexicalAnalysis.COMMASY)
{
i++;
lex = (LexicalAnalysisResult)Lexresult[i];
if (lex.Type == LexicalAnalysis.IDSY)
{
//PCODE?
//检查符号表
int preloc = -1;
for (int ind = symbols.Count - 1; ind >= 0; ind--)
{
Symbols tempsym = (Symbols)symbols[ind];
if (lex.Content.Equals(tempsym.Name) && level >= tempsym.Level)
{
preloc = ind;
break;
}
}
if (preloc == -1)
{
flag = false;
Console.WriteLine("错误：不存在符号{0}", lex.Content);
errors.Add(new Error("错误：不存在符号" + lex.Content, lex.Line));
return;
}
Symbols sym = (Symbols)symbols[preloc];
PCodes.Add(new PCode(codeAddr, PCode.INT, 0, 1));
codeAddr++;
PCodes.Add(new PCode(codeAddr, PCode.LOD, level - sym.Level, sym.Addr));
codeAddr++;
PCodes.Add(new PCode(codeAddr, PCode.WRT, 0, 0));
codeAddr++;
//i++;
}
else if (lex.Type == LexicalAnalysis.INTSY)
{
PCodes.Add(new PCode(codeAddr, PCode.INT, 0, 1));
codeAddr++;
PCodes.Add(new PCode(codeAddr, PCode.LIT, 0, Convert.ToInt32(lex.Content)));
codeAddr++;
PCodes.Add(new PCode(codeAddr, PCode.WRT, 0, 0));
codeAddr++;
}
else
{
flag = false;
Console.WriteLine("无标识符");
errors.Add(new Error("错误：无标识符", lex.Line));
return;
}
i++;
lex = (LexicalAnalysisResult)Lexresult[i];
}
if (lex.Type != LexicalAnalysis.RPARSY)
{
flag = false;
Console.WriteLine("错误：此处应为)");
errors.Add(new Error("错误：此处应补充)", lex.Line));
return;
}
else
{
i++;
return;
}
}
