static int Compiler_compileNameNode(Context* context, Node* node) {
const char* name = node->data.sval;
if (!strcmp(name, "true")) {
Block_append(context->block, OP_BOOL, context->reg, 1);
return context->reg++;
}
else if (!strcmp(name, "false")) {
Block_append(context->block, OP_BOOL, context->reg, 0);
return context->reg++;
}
else if (!strcmp(name, "nil")) {
Block_append(context->block, OP_NIL, context->reg);
return context->reg++;
}
Reg reg = SymTab_lookup(context->symtab, name);
if (reg < 0) {
fprintf(stderr, "name %s not defined\n", name);
Compiler_error(context);
}
return reg;
}
static int Compiler_compileAssignNode(Context* context, Node* node) {
int reg = SymTab_lookup(context->symtab, node->data.sval);
int obj = Compiler_compile(context, node->right);
if (reg < 0) {
SymTab_store(context->symtab, node->data.sval, context->reg);
reg = context->reg++;
}
Block_append(context->block, OP_MOV, reg, obj);
return reg;
}
int tree_gen_assignmentExpression(struct tree *t)
{
//get the token name
char *tname = tree_get_ident(t);
//if no token name, this is a right hand assignmentExpression with a
// literal, which we'll ignore now and handle when we see the entire
//expression later (below)
if(tname == NULL)
{
return(0);
}
//else, this is an entire assignmentExpression to a identifier
else
{
SymTabEntry *p = SymTab_lookup(tname);
//get the subtree symbol for report info
struct tree *temp = NULL;
tree_get_subtree(tname, t, &temp);
//use before declaration check
if(p == NULL)
{
if(temp != NULL)
{
struct tree_token *symbol = temp->leaf;
fprintf(stderr,
"ERROR: identifier '%s' used before declared, in file '%s' on line %d\n",
tname, symbol->fname, symbol->lineno);
}
else
{
fprintf(stderr,
"ERROR: identifier '%s' used before declared, and some horrible internal errors also occured.\n",
tname);
}
exit(ERROR_SEMANTIC);
}
//assignment to const check
if(p->aux_flag != NULL
&& strcmp(p->aux_flag, "const") == 0)
{
if(temp != NULL)
{
struct tree_token *symbol = temp->leaf;
fprintf(stderr,
"ERROR: assignment to constant '%s', in file '%s' on line %d\n",
tname, symbol->fname, symbol->lineno);
}
else
{
fprintf(stderr,
"ERROR: assignment to constant '%s', and some horrible internal errors also occured.\n",
tname);
}
exit(ERROR_SEMANTIC);
}
} //end else (if tname != NULL
//otherwise, some tac gen here
return(0); //success
}
