?? plxcompiler.cpp
字號:
}
else //出錯了
{
error(14);
}
if(m_sym==EQL || m_sym==GTR || m_sym==GEQ || m_sym==LSS || m_sym==LEQ || m_sym==NEQ)
{
op=m_sym;
getSym();
}
else
{
error(15);
}
this->ArithmeticExpression(level,fsys);
switch(op)
{
case EQL:
gen(OPR,0,9);
break;
case GTR:
gen(OPR,0,13);
break;
case GEQ:
gen(OPR,0,14);
break;
case LSS:
gen(OPR,0,11);
break;
case LEQ:
gen(OPR,0,12);
break;
case NEQ:
gen(OPR,0,10);
break;
default:
;
}
}
//處理ae非終結符
void PLXCompiler::ArithmeticExpression(int level,symset fsys)
{
symset tmp,tmp1;
symbol minusOp=NUL;
tmp=fsys;
tmp.insert(PLUS);
tmp.insert(MINUS);
if(m_sym==MINUS)
{
getSym();
minusOp=m_sym;
}
this->ArithmeticTerm(level,tmp);
if(minusOp==MINUS)
{
gen(OPR,0,1);//取負
}
tmp1=this->m_firstaf;
tmp1.insert(MINUS);
tmp1.insert(PLUS);
tmp1.insert(NUL);
while(tmp1.find(m_sym)!=tmp1.end())
{
if(m_sym==MINUS || m_sym==PLUS)
{
minusOp=m_sym;
getSym();
}
else if(m_sym==NUL)
{
error(38);
getSym();
}
else
{
error(38);
}
this->ArithmeticTerm(level,tmp);
if(minusOp==MINUS)
{
gen(OPR,0,3);//減
}
if(minusOp==PLUS)
{
gen(OPR,0,2);//加
}
}
}
//處理at非終結符
void PLXCompiler::ArithmeticTerm(int level,symset fsys)
{
symset tmp,tmp1;
symbol op=NUL;
tmp=fsys;
tmp.insert(TIMES);
tmp.insert(SLASH);
this->ArithmeticFactor(level,tmp);
while(m_sym==TIMES || m_sym==SLASH)
{
op=m_sym;
getSym();
this->ArithmeticFactor(level,tmp);
if(op==TIMES)
{
gen(OPR,0,4);
}
if(op==SLASH)
{
gen(OPR,0,5);
}
}
}
//處理af非終結符
void PLXCompiler::ArithmeticFactor(int level,symset fsys)
{
symset tmp;
test(this->m_firstaf,fsys,32);
if(m_sym==IDENT)
{
//查找符號表
vector<item>::iterator iter=this->position(m_id);
if(NULL==iter)
{
error(1); //變量為定義
}
else
{
if(iter->kind!=aident)
{
error(2);//此處變量需為整型
}
else
{
gen(LOD,level-iter->level,iter->adr);
}
}
getSym();
}
else if(m_sym==NUMBER)
{
gen(LIT,0,this->m_num);
getSym();
}
else if(m_sym==LPAREN)
{
getSym();
tmp.clear();
tmp=fsys;
tmp.insert(RPAREN);
this->ArithmeticExpression(level,tmp);
if(m_sym!=RPAREN)
{
error(3);//缺了')'
}
else
getSym();
}
else
{
error(4);//
}
}
//處理非終結符be
void PLXCompiler::BoolExpression(int level,symset fsys)
{
symset tmp=fsys;
symbol op=NUL;
tmp.insert(ORSYM);
this->BoolTerm(level,tmp);
while(m_sym==ORSYM)
{
op=m_sym;
getSym();
this->BoolTerm(level,tmp);
if(op==ORSYM)
{
gen(OPR,0,6);//OR
}
}
tmp.clear();
tmp.insert(THENSYM);
tmp.insert(DOSYM);
test(fsys,tmp,34);
}
//處理非終結符bt
void PLXCompiler::BoolTerm(int level,symset fsys)
{
symset tmp=fsys;
symbol op;
tmp.insert(ANDSYM);
this->BoolFactor(level,tmp);
while(m_sym==ANDSYM)
{
op=m_sym;
getSym();
this->BoolFactor(level,tmp);
if(op==ANDSYM)
{
gen(OPR,0,7);//AND
}
}
}
//處理非終結符bf
void PLXCompiler::BoolFactor(int level,symset fsys)
{
symset tmp;
symbol op;
test(this->m_firstbf,fsys,6);
if(m_sym==IDENT)
{
//查找符號表
vector<item>::iterator iter=this->position(m_id);
if(NULL==iter)
{
error(1); //變量為定義
getSym();
}
else
{
if(iter->kind==bident)
{
gen(LOD,level-iter->level,iter->adr);
getSym();
}
else if(iter->kind==aident)
{
tmp.clear();
tmp=fsys;
this->RelationExpression(level,fsys);
}
else
{
error(5);//非法的變量
getSym();
}
}
}
else if(m_sym==TRUESYM || m_sym==FALSESYM)
{
if(m_sym==TRUESYM)
{
gen(LIT,0,1);
}
else
{
gen(LIT,0,0);
}
getSym();
}
else if(m_sym==NOTSYM)
{
op=m_sym;
getSym();
tmp.clear();
tmp=fsys;
this->BoolFactor(level,tmp);
if(op==NOTSYM)
{
gen(OPR,0,8);//NOT
}
}
else if(m_sym==LPAREN)
{
getSym();
tmp.clear();
tmp=fsys;
tmp.insert(RPAREN);
this->BoolExpression(level,tmp);
if(m_sym!=RPAREN)
{
error(3);//缺少')'
}
else
getSym();
}
else if(m_sym==NUMBER)
{
tmp.clear();
tmp=fsys;
this->RelationExpression(level,tmp);
}
else
{
error(6);
}
// tmp.clear();
// tmp.insert(DOSYM);
//tmp.insert(THENSYM);
// tmp.insert(ENDSYM);
//test(fsys,tmp,34);
}
//
void PLXCompiler::ProcedureSque(int level,symset fsys)
{
symset tmp;
while(m_sym==PROSYM)
{
this->Procedure(level,fsys);
}
tmp.clear();
tmp=this->m_firsts;
tmp.insert(ENDSYM);
test(fsys,tmp,35);
}
//處理非終結符proc
void PLXCompiler::Procedure(int level,symset fsys)
{
symset tmp,stop;
alfa name;//保存函數名
vector<item>::iterator iter=NULL;
int k=0;
vector<item>::iterator pt;
int dx=3,tx=m_tx,cx=m_cx;
if(m_sym==PROSYM)
{
gen(JMP,0,0);
getSym();
if(m_sym==IDENT)
{
//在符號表中登記函數名
enter(pident,level);
strcpy(name,m_id);
}
else
{
error(7); //非法的變量名
}
getSym();
if(m_sym!=LPAREN)
{
error(33);//缺了'('
}
else
getSym();
if(m_sym==INTESYM)
{
getSym();
k++;
if(m_sym==IDENT)
{
enter(aident,dx,level+1);
}
else
{
error(9);//非法的參數名
}
getSym();
while(m_sym==COMMA || m_sym==IDENT)
{
if(m_sym==COMMA)
getSym();
else
error(19);
if(m_sym==IDENT)
{
enter(aident,dx,level+1);
k++;
}
else
{
error(9);//非法的參數名
k++;
}
getSym();
}
}
if(m_sym!=RPAREN)
{
error(3);//缺了')'
}
else
getSym();
//
this->DefinitionSque(level+1,dx,fsys);
if(m_sym!=BEGINSYM)
{
error(10);//缺了begin
}
else
getSym();
this->Procedure(level+1,fsys);
tmp.clear();
tmp=fsys;
tmp.insert(ENDSYM);
//修改參數信息,函數的局部變量所需空間大小，函數地址
pt=m_table.begin()+tx;
if(pt!=NULL)
{
(*((m_code.begin()+cx))).a=m_cx;
pt->num=k;
pt->adr=m_cx;
pt->size=dx;
}
gen(INT,0,dx);
this->SentenceSque(level+1,tmp);
gen(OPR,0,0);
if(m_sym!=ENDSYM)
{
error(11);//缺了end
}
else
getSym();
tmp=fsys;
tmp.insert(PROSYM);
stop.clear();
stop=this->m_firsts;
stop.insert(ENDSYM);
test(tmp,stop,35);
}
}
//處理非終結符S
void PLXCompiler::Sentence(int level,symset fsys)
{
int k=0,num=0; //用來記錄函數的參數個數
vector<item>::iterator pfunction,pParameter;
item _item;//
int cx1,cx2,cx3;
symset tmp;
test(this->m_firsts,fsys,30);
if(m_sym==IDENT)
{
//查找符號表
vector<item>::iterator iter=this->position(m_id);
if(NULL==iter)
{
error(1); //變量未定義
getSym();
//若變量沒定義則當作整型變量
if(m_sym!=BECOMES)
error(22); //此處應為":="
else
getSym();
tmp.clear();
set_union(fsys.begin(),fsys.end(),m_followae.begin(),m_followae.end(),insert_iterator<symset>(tmp,tmp.begin()));
this->ArithmeticExpression(level,tmp);
}
else if(iter->kind==aident)
{
getSym();
if(m_sym!=BECOMES)
error(22); //此處應為":="
else
getSym();
tmp.clear();
set_union(fsys.begin(),fsys.end(),m_followae.begin(),m_followae.end(),insert_iterator<symset>(tmp,tmp.begin()));
this->ArithmeticExpression(level,tmp);
//產生一條賦值語句
gen(STO,level-iter->level,iter->adr);
}
else if(iter->kind==bident)
{
getSym();
if(m_sym!=BECOMES)
error(22); //此處應為":="
getSym();
tmp.clear();
set_union(fsys.begin(),fsys.end(),m_followbe.begin(),m_followbe.end(),insert_iterator<symset>(tmp,tmp.begin()));
this->BoolExpression(level,tmp);
//產生一條賦值語句
gen(STO,level-iter->level,iter->adr);
}
else
{
error(23);//此處不能為函數名
getSym();
}
}
else if(m_sym==IFSYM)
{
getSym();
tmp.clear();
set_union(fsys.begin(),fsys.end(),m_followbe.begin(),m_followbe.end(),insert_iterator<symset>(tmp,tmp.begin()));
this->BoolExpression(level,tmp);
if(m_sym!=THENSYM)
error(24); //缺了then
else
getSym();
tmp.clear();
set_union(fsys.begin(),fsys.end(),m_followss.begin(),m_followss.end(),insert_iterator<symset>(tmp,tmp.begin()));
cx1=this->m_cx;
gen(JPC,0,0);
this->SentenceSque(level,tmp);
cx2=this->m_cx;
if(m_sym==ELSESYM)
{
gen(JMP,0,0);
getSym();
this->SentenceSque(level,tmp);
(*(m_code.begin()+cx2)).a=m_cx;
(*(m_code.begin()+cx1)).a=cx2+1;
}
else
(*(m_code.begin()+cx1)).a=cx2;
if(m_sym!=ENDSYM)
error(11);//缺了end
else
getSym();
}
else if(m_sym==WHILESYM)
{
cx1=m_cx;
getSym();
tmp.clear();
set_union(fsys.begin(),fsys.end(),m_followbe.begin(),m_followbe.end(),insert_iterator<symset>(tmp,tmp.begin()));
this->BoolExpression(level,tmp);
cx2=m_cx;
gen(JPC,0,0);
if(m_sym!=DOSYM)
error(26);//缺了do
else
getSym();
tmp.clear();
set_union(fsys.begin(),fsys.end(),m_followss.begin(),m_followss.end(),insert_iterator<symset>(tmp,tmp.begin()));
this->SentenceSque(level,tmp);
gen(JMP,0,cx1);
(*(m_code.begin()+cx2)).a=m_cx;
if(m_sym!=ENDSYM)
error(11);//缺了end
getSym();
}
else if(m_sym==REPEATSYM)
{
cx1=m_cx;
getSym();
tmp.clear();
set_union(fsys.begin(),fsys.end(),m_followss.begin(),m_followss.end(),insert_iterator<symset>(tmp,tmp.begin()));
this->SentenceSque(level,tmp);
if(m_sym!=UNTILSYM)
error(27);
else
getSym();
tmp.clear();
set_union(fsys.begin(),fsys.end(),m_followbe.begin(),m_followbe.end(),insert_iterator<symset>(tmp,tmp.begin()));
this->BoolExpression(level,tmp);
gen(OPR,0,8);
cx2=m_cx;
gen(JPC,0,0);
gen(JMP,0,cx1);
(*(m_code.begin()+cx2)).a=m_cx;
}
else if(m_sym==WRITESYM)
{
getSym();
tmp.clear();
set_union(fsys.begin(),fsys.end(),m_followae.begin(),m_followae.end(),insert_iterator<symset>(tmp,tmp.begin()));
this->ArithmeticExpression(level,tmp);
gen(OPR,0,15);
}
else if(m_sym==READSYM)
{
getSym();
if(m_sym==IDENT)
{
//查找符號表
vector<item>::iterator iter=this->position(m_id);
if(NULL==iter)
{
error(1); //變量為定義
//getSym();
}
else
{
if(iter->kind!=aident)
error(13);
else
{
gen(OPR,0,16);
gen(STO,level-iter->level,iter->adr);
}
//getSym();
}
}
else
{
error(13);//此處為一個整型變量名
}
getSym();
}
else if(m_sym==FORSYM)
{
getSym();
if(m_sym==IDENT)
{
//查找符號表
vector<item>::iterator iter=this->position(m_id);
if(NULL==iter)
{
error(1); //變量為定義
}
else
{
if(iter->kind!=aident)
{
error(13);
}
else
{
cx1=m_cx;
_item.adr=iter->adr;
_item.level=iter->level;
gen(LOD,level-iter->level,iter->adr);
}
}
}
else
{
error(13);//此處為一個整型變量名
}
getSym();
if(m_sym!=FROMSYM)
{
error(25);//缺了from
}
else
getSym();
if(m_sym==IDENT)
{
//查找符號表
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