void closeScope()
{
if(symbolTable.currentLevel < 0)
{
printf("void closeScope(): Error: current level < 0. No scope can be close.\n");
return;
}
SymbolTableEntry* scopeChain = symbolTable.scopeDisplay[symbolTable.currentLevel];
SymbolTableEntry* nextScopeChain = NULL;
while(scopeChain)
{
int hashIndex = HASH(scopeChain->name);
removeFromHashTrain(hashIndex, scopeChain);
if(scopeChain->sameNameInOuterLevel)
{
enterIntoHashTrain(hashIndex, scopeChain->sameNameInOuterLevel);
}
nextScopeChain = scopeChain->nextInSameLevel;
scopeChain = nextScopeChain;
}
//
symbolTable.scopeDisplay[symbolTable.currentLevel] = NULL;
//
--symbolTable.currentLevel;
}
//remove the symbol from the current scope
void removeSymbol(char* symbolName)
{
int hashIndex = HASH(symbolName);
SymbolTableEntry* hashChain = symbolTable.hashTable[hashIndex];
while(hashChain)
{
if(strcmp(hashChain->name, symbolName) == 0)
{
if(hashChain->nestingLevel != symbolTable.currentLevel)
{
printf("void removeSymbol(...) Error: try to removed ID \'%s\' from the scope other than currentScope.\n", symbolName);
return;
}
else
{
removeFromHashTrain(hashIndex, hashChain);
if(hashChain->sameNameInOuterLevel)
{
enterIntoHashTrain(hashIndex, hashChain->sameNameInOuterLevel);
}
break;
}
}
else
{
hashChain = hashChain->nextInHashChain;
}
}
if(!hashChain)
{
printf("void removeSymbol(...) Error: try to removed ID \'%s\' not in the symbol table.\n", symbolName);
return;
}
SymbolTableEntry* tmpPrev = NULL;
SymbolTableEntry* scopeChain = symbolTable.scopeDisplay[symbolTable.currentLevel];
while(scopeChain)
{
if(strcmp(scopeChain->name, symbolName) == 0)
{
if(tmpPrev)
{
tmpPrev->nextInSameLevel = scopeChain->nextInSameLevel;
}
else
{
symbolTable.scopeDisplay[symbolTable.currentLevel] = scopeChain->nextInSameLevel;
}
free(scopeChain);
break;
}
else
{
tmpPrev = scopeChain;
scopeChain = scopeChain->nextInSameLevel;
}
}
}
SymbolTableEntry* enterSymbol(char* symbolName, SymbolAttribute* attribute)
{
int hashIndex = HASH(symbolName);
SymbolTableEntry* hashChain = symbolTable.hashTable[hashIndex];
SymbolTableEntry* newEntry = newSymbolTableEntry(symbolTable.currentLevel);
newEntry->attribute = attribute;
newEntry->name = symbolName;
if(attribute->attributeKind == VARIABLE_ATTRIBUTE) {
if(symbolTable.currentLevel != 0) {
if(attribute->attr.typeDescriptor->kind == SCALAR_TYPE_DESCRIPTOR) {
ARoffset -= 4;
}else {
int i, size = 4;
ArrayProperties temp = attribute->attr.typeDescriptor->properties.arrayProperties;
for(i=0; i<temp.dimension; i++)
size *= temp.sizeInEachDimension[i];
ARoffset -= size;
}
}
newEntry->offset = ARoffset;
}
while(hashChain)
{
if(strcmp(hashChain->name, symbolName) == 0)
{
if(hashChain->nestingLevel == symbolTable.currentLevel)
{
printf("void enterSymbol(...): ID \'%s\' is redeclared(at the same level#%d).\n", symbolName, symbolTable.currentLevel);
free(newEntry);
return NULL;
}
else
{
removeFromHashTrain(hashIndex, hashChain);
newEntry->sameNameInOuterLevel = hashChain;
break;
}
}
else
{
hashChain = hashChain->nextInHashChain;
}
}
enterIntoHashTrain(hashIndex, newEntry);
newEntry->nextInSameLevel = symbolTable.scopeDisplay[symbolTable.currentLevel];
symbolTable.scopeDisplay[symbolTable.currentLevel] = newEntry;
return newEntry;
}
SymbolTableEntry* enterSymbol(char* symbolName, SymbolAttribute* attribute)
{
SymbolTableEntry* oldsym = retrieveSymbol(symbolName);
if(oldsym != NULL && oldsym.nestingLevel == sybolTable.currentLevel)
{
printf("Error: %s has been redecalred!");
g_anyErrorOccur = 1;
return oldsym;
}
//new entry
SymbolTableEntry* newsym = newSymbolTableEntry(symbolName, sybolTable.currentLevel);
newsym.attribute = attribute;//the space of attribute may be changed,need to be careful.
//add to scope display
newsym.nextInSameLevel = symbolTable.scopeDisplay[symbolTable.currentLevel];
symbolTable.scopeDisplay[symbolTable.currentLevel] = newsym;
//add to hash table
if(oldsym == NULL) enterIntoHashTrain(newsym);
else
{
removeFromHashTrain(oldsym);
enterIntoHashTrain(newsym);
}
newsym.sameNameInOuterLevel = oldsym;
}
void closeScope()
{
SymbolTableEntry* sym;
sym = sybolTable.scopeDisplay[sybolTable.currentLevel];
while(sym!=NULL)
{
SymbolTableEntry* nextInSameLevel = sym.nextInSameLevel;
SymbolTableEntry* prevsym = sym.
removeFromHashTrain(sym);
if(prevsym != NULL) enterIntoHashTrain(prevsym);
sym=nextInSameLevel;
}
symbolTable.currentLevel--;
}
SymbolTableEntry* enterSymbol(char* symbolName, SymbolAttribute* attribute)
{
int hashIndex = HASH(symbolName);
SymbolTableEntry* hashChain = symbolTable.hashTable[hashIndex];
SymbolTableEntry* newEntry = newSymbolTableEntry(symbolTable.currentLevel);
newEntry->attribute = attribute;
newEntry->name = symbolName;
if(attribute->attributeKind == VARIABLE_ATTRIBUTE)
{
newEntry->offset = ARoffset;
ARoffset -= calc_size(attribute->attr.typeDescriptor);
}
while(hashChain)
{
if(strcmp(hashChain->name, symbolName) == 0)
{
if(hashChain->nestingLevel == symbolTable.currentLevel)
{
printf("void enterSymbol(...): ID \'%s\' is redeclared(at the same level#%d).\n", symbolName, symbolTable.currentLevel);
free(newEntry);
return NULL;
}
else
{
removeFromHashTrain(hashIndex, hashChain);
newEntry->sameNameInOuterLevel = hashChain;
break;
}
}
else
{
hashChain = hashChain->nextInHashChain;
}
}
enterIntoHashTrain(hashIndex, newEntry);
newEntry->nextInSameLevel = symbolTable.scopeDisplay[symbolTable.currentLevel];
symbolTable.scopeDisplay[symbolTable.currentLevel] = newEntry;
return newEntry;
}