// Build a new string literal. String literals
// are arrays of characters.
Expr*
Parser::on_str(Token tok)
{
// Build the string value.
String_sym const* s = tok.string_symbol();
Array_value v {
s->value().c_str(),
s->value().size()
};
// Create the extent of the literal array. This is
// explicitly more than the length of the string,
// and includes the null character.
Type const* z = get_integer_type();
Expr* n = new Literal_expr(z, v.len + 1);
// Create the array type.
Type const* c = get_character_type();
Type const* t = get_array_type(c, n);
return init<Literal_expr>(tok.location(), t, v);
}
// Return the value corresponding to a literal expression.
llvm::Value*
Generator::gen(Literal_expr const* e)
{
// TODO: Write better type queries.
//
// TODO: Write a better interface for values.
Value v = evaluate(e);
Type const* t = e->type();
if (t == get_boolean_type())
return build.getInt1(v.get_integer());
if (t == get_character_type())
return build.getInt8(v.get_integer());
if (t == get_integer_type())
return build.getInt32(v.get_integer());
// FIXME: How should we generate array literals? Are
// these global constants or are they local alloca
// objects. Does it depend on context?
// A string literal produces a new global string constant.
// and returns a pointer to an array of N characters.
if (is_string(t)) {
Array_value a = v.get_array();
String s = a.get_string();
// FIXME: This does not unify equivalent strings.
// Maybe we needt maintain a mapping in order to
// avoid redunancies.
auto iter = strings.find(s);
if (iter == strings.end()) {
llvm::Value* v = build.CreateGlobalString(s);
iter = strings.emplace(s, v).first;
}
return iter->second;
}
else
throw std::runtime_error("cannot generate function literal");
}
// Parse a primary type.
//
// primary-type -> 'bool'
// | 'int'
// | 'char'
// | id-type
// | function-type
//
// function-type -> '(' type-list ')' '->' type
//
// type-list -> type | type-list ',' type
Type const*
Parser::primary_type()
{
// id-type
if (Token tok = match_if(identifier_tok))
return on_id_type(tok);
// bool
else if (match_if(bool_kw))
return get_boolean_type();
// char
else if (match_if(char_kw))
return get_character_type();
// int
else if (match_if(int_kw))
return get_integer_type();
// uint
else if (match_if(uint_kw))
return get_integer_type(false);
// short
else if (match_if(short_kw))
return get_integer_type(16);
// ushort
else if (match_if(ushort_kw))
return get_integer_type(false, 16);
// long
else if (match_if(long_kw))
return get_integer_type(64);
// ulong
else if (match_if(ulong_kw))
return get_integer_type(false, 64);
// int16
else if (match_if(int16_kw))
return get_integer_type(16);
// uint16
else if (match_if(uint16_kw))
return get_integer_type(false, 16);
// int32
else if (match_if(int32_kw))
return get_integer_type();
// uint32
else if (match_if(uint32_kw))
return get_integer_type(false);
// int64
else if (match_if(int64_kw))
return get_integer_type(64);
// uint64
else if (match_if(uint64_kw))
return get_integer_type(false, 64);
// float
else if (match_if(float_kw))
return get_float_type();
// double
else if (match_if(double_kw))
return get_double_type();
// function-type
else if (match_if(lparen_tok)) {
Type_seq ts;
while (true) {
ts.push_back(type());
if (match_if(comma_tok))
continue;
else
break;
}
match(rparen_tok);
match(arrow_tok);
Type const* t = type();
return on_function_type(ts, t);
}
// error
//
// TODO: Make this a little less vague.
else
error("invalid type");
}
