/**
*
* Returns a pointer to a symbol table instance
*
* @param size the size of the symbol table
* @return symbol table with 'size' entries
*/
SymTable SymInit(unsigned int size)
{
register SymTable ip;
register int power, i;
if (size < 8)
size = 8;
ip = (SymTable) malloc(sizeof(struct SymTable_internal_structure));
/* compute a size for the sparse index set */
power = 0;
i = 31;
while(i > 1)
{
if (size & 1<<i)
{
if (i < 20) /* make the index set 2 to 4 * size */
power = (1 << (i+2)) -1;
else /* the set is too large, anyway */
power = (1 << i) -1;
i = 0; /* exit the little loop */
}
i--;
}
ip->NumFields = FS;
ip->FieldVals = (Generic**)malloc(FS*sizeof(Generic*));
ip->FieldNames = (char**)malloc(FS*sizeof(char*));
ip->CleanupFns = (SymCleanupFunc*)malloc(FS*sizeof(void*));
ip->InitVals = (Generic*)malloc(FS*sizeof(Generic*));
bzero((char *)ip->FieldVals, FS*sizeof(Generic*));
bzero((char *)ip->FieldNames, FS*sizeof(char*));
bzero((char *)ip->CleanupFns, FS*sizeof(void*));
bzero((char *)ip->InitVals, FS*sizeof(Generic*));
ip->NumSlots = size;
ip->NextSlot = FIRST_SLOT; /* added JMC 14 March 1991 */
ip->NumIndices = power;
ip->Index = (int*) malloc(power*sizeof(int));
for (i=0; i<power;i++) /* fill in the index set */
ip->Index[i] = -1;
SymInitField(ip,SYM_NAME_FIELD, 0, sfree_if_nonzero);
ip->NameField = SymFieldIndex(ip, SYM_NAME_FIELD);
#ifdef DEBUG
fprintf(stderr, "SymInit(%d): sparse index size set to %d.\n", size, power);
fprintf(stderr, "\tFields: %d, Slots: %d, Next Slot: %d, Name Field: %d.\n",
ip->NumFields, ip->NumSlots, ip->NextSlot, ip->NameField);
#endif
return ip;
}
/**
* Push a new symbol table on the stack when entering a new scope region
*
* @param stack a stack of symbol tables
* @return a new symbol table
*/
SymTable beginScope(SymtabStack stack) {
SymTable symtab = SymInit(SYMTABLE_SIZE);
SymInitField(symtab,SYMTAB_OFFSET_FIELD,(Generic)-1,NULL);
SymInitField(symtab,SYMTAB_REGISTER_INDEX_FIELD,(Generic)-1,NULL);
int intIndex = SymIndex(symtab,SYMTAB_INTEGER_TYPE_STRING);
int errorIndex = SymIndex(symtab,SYMTAB_ERROR_TYPE_STRING);
int voidIndex = SymIndex(symtab,SYMTAB_VOID_TYPE_STRING);
SymPutFieldByIndex(symtab,intIndex,SYMTAB_SIZE_FIELD,(Generic)INTEGER_SIZE);
SymPutFieldByIndex(symtab,errorIndex,SYMTAB_SIZE_FIELD,(Generic)0);
SymPutFieldByIndex(symtab,voidIndex,SYMTAB_SIZE_FIELD,(Generic)0);
SymPutFieldByIndex(symtab,intIndex,SYMTAB_BASIC_TYPE_FIELD,(Generic)INTEGER_TYPE);
SymPutFieldByIndex(symtab,errorIndex,SYMTAB_BASIC_TYPE_FIELD,(Generic)ERROR_TYPE);
SymPutFieldByIndex(symtab,voidIndex,SYMTAB_BASIC_TYPE_FIELD,(Generic)VOID_TYPE);
dlinkPush(dlinkNodeAlloc((Generic)symtab),stack);
int *size = (int*)dlinkListAtom(stack);
(*size)++;
return symtab;
}
