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#include "ast.hpp"
#include <ostream>
#include "binop.hpp"
#include "error.hpp"
#include "type_env.hpp"
#include "env.hpp"
static void print_indent(int n, std::ostream& to) {
while(n--) to << " ";
}
void ast_int::print(int indent, std::ostream& to) const {
print_indent(indent, to);
to << "INT: " << value << std::endl;
}
void ast_int::find_free(std::set<std::string>& into) {
}
type_ptr ast_int::typecheck(type_mgr& mgr, type_env_ptr& env) {
this->env = env;
return type_ptr(new type_app(env->lookup_type("Int")));
}
void ast_int::translate(global_scope& scope) {
}
void ast_int::compile(const env_ptr& env, std::vector<instruction_ptr>& into) const {
into.push_back(instruction_ptr(new instruction_pushint(value)));
}
void ast_lid::print(int indent, std::ostream& to) const {
print_indent(indent, to);
to << "LID: " << id << std::endl;
}
void ast_lid::find_free(std::set<std::string>& into) {
into.insert(id);
}
type_ptr ast_lid::typecheck(type_mgr& mgr, type_env_ptr& env) {
this->env = env;
return env->lookup(id)->instantiate(mgr);
}
void ast_lid::translate(global_scope& scope) {
}
void ast_lid::compile(const env_ptr& env, std::vector<instruction_ptr>& into) const {
auto mangled_name = this->env->get_mangled_name(id);
into.push_back(instruction_ptr(
(env->has_variable(mangled_name) && !this->env->is_global(id)) ?
(instruction*) new instruction_push(env->get_offset(mangled_name)) :
(instruction*) new instruction_pushglobal(mangled_name)));
}
void ast_uid::print(int indent, std::ostream& to) const {
print_indent(indent, to);
to << "UID: " << id << std::endl;
}
void ast_uid::find_free(std::set<std::string>& into) {
}
type_ptr ast_uid::typecheck(type_mgr& mgr, type_env_ptr& env) {
this->env = env;
return env->lookup(id)->instantiate(mgr);
}
void ast_uid::translate(global_scope& scope) {
}
void ast_uid::compile(const env_ptr& env, std::vector<instruction_ptr>& into) const {
into.push_back(instruction_ptr(
new instruction_pushglobal(this->env->get_mangled_name(id))));
}
void ast_binop::print(int indent, std::ostream& to) const {
print_indent(indent, to);
to << "BINOP: " << op_name(op) << std::endl;
left->print(indent + 1, to);
right->print(indent + 1, to);
}
void ast_binop::find_free(std::set<std::string>& into) {
left->find_free(into);
right->find_free(into);
}
type_ptr ast_binop::typecheck(type_mgr& mgr, type_env_ptr& env) {
this->env = env;
type_ptr ltype = left->typecheck(mgr, env);
type_ptr rtype = right->typecheck(mgr, env);
type_ptr ftype = env->lookup(op_name(op))->instantiate(mgr);
if(!ftype) throw type_error(std::string("unknown binary operator ") + op_name(op));
type_ptr return_type = mgr.new_type();
type_ptr arrow_one = type_ptr(new type_arr(rtype, return_type));
type_ptr arrow_two = type_ptr(new type_arr(ltype, arrow_one));
mgr.unify(arrow_two, ftype);
return return_type;
}
void ast_binop::translate(global_scope& scope) {
left->translate(scope);
right->translate(scope);
}
void ast_binop::compile(const env_ptr& env, std::vector<instruction_ptr>& into) const {
right->compile(env, into);
left->compile(env_ptr(new env_offset(1, env)), into);
into.push_back(instruction_ptr(new instruction_pushglobal(op_action(op))));
into.push_back(instruction_ptr(new instruction_mkapp()));
into.push_back(instruction_ptr(new instruction_mkapp()));
}
void ast_app::print(int indent, std::ostream& to) const {
print_indent(indent, to);
to << "APP:" << std::endl;
left->print(indent + 1, to);
right->print(indent + 1, to);
}
void ast_app::find_free(std::set<std::string>& into) {
left->find_free(into);
right->find_free(into);
}
type_ptr ast_app::typecheck(type_mgr& mgr, type_env_ptr& env) {
this->env = env;
type_ptr ltype = left->typecheck(mgr, env);
type_ptr rtype = right->typecheck(mgr, env);
type_ptr return_type = mgr.new_type();
type_ptr arrow = type_ptr(new type_arr(rtype, return_type));
mgr.unify(arrow, ltype);
return return_type;
}
void ast_app::translate(global_scope& scope) {
left->translate(scope);
right->translate(scope);
}
void ast_app::compile(const env_ptr& env, std::vector<instruction_ptr>& into) const {
right->compile(env, into);
left->compile(env_ptr(new env_offset(1, env)), into);
into.push_back(instruction_ptr(new instruction_mkapp()));
}
void ast_case::print(int indent, std::ostream& to) const {
print_indent(indent, to);
to << "CASE: " << std::endl;
for(auto& branch : branches) {
print_indent(indent + 1, to);
branch->pat->print(to);
to << std::endl;
branch->expr->print(indent + 2, to);
}
}
void ast_case::find_free(std::set<std::string>& into) {
of->find_free(into);
for(auto& branch : branches) {
std::set<std::string> free_in_branch;
std::set<std::string> pattern_variables;
branch->pat->find_variables(pattern_variables);
branch->expr->find_free(free_in_branch);
for(auto& free : free_in_branch) {
if(pattern_variables.find(free) == pattern_variables.end())
into.insert(free);
}
}
}
type_ptr ast_case::typecheck(type_mgr& mgr, type_env_ptr& env) {
this->env = env;
type_var* var;
type_ptr case_type = mgr.resolve(of->typecheck(mgr, env), var);
type_ptr branch_type = mgr.new_type();
for(auto& branch : branches) {
type_env_ptr new_env = type_scope(env);
branch->pat->typecheck(case_type, mgr, new_env);
type_ptr curr_branch_type = branch->expr->typecheck(mgr, new_env);
mgr.unify(branch_type, curr_branch_type);
}
input_type = mgr.resolve(case_type, var);
type_app* app_type;
if(!(app_type = dynamic_cast<type_app*>(input_type.get())) ||
!dynamic_cast<type_data*>(app_type->constructor.get())) {
throw type_error("attempting case analysis of non-data type");
}
return branch_type;
}
void ast_case::translate(global_scope& scope) {
of->translate(scope);
for(auto& branch : branches) {
branch->expr->translate(scope);
}
}
void ast_case::compile(const env_ptr& env, std::vector<instruction_ptr>& into) const {
type_app* app_type = dynamic_cast<type_app*>(input_type.get());
type_data* type = dynamic_cast<type_data*>(app_type->constructor.get());
of->compile(env, into);
into.push_back(instruction_ptr(new instruction_eval()));
instruction_jump* jump_instruction = new instruction_jump();
into.push_back(instruction_ptr(jump_instruction));
for(auto& branch : branches) {
std::vector<instruction_ptr> branch_instructions;
pattern_var* vpat;
pattern_constr* cpat;
if((vpat = dynamic_cast<pattern_var*>(branch->pat.get()))) {
branch->expr->compile(env_ptr(new env_offset(1, env)), branch_instructions);
for(auto& constr_pair : type->constructors) {
if(jump_instruction->tag_mappings.find(constr_pair.second.tag) !=
jump_instruction->tag_mappings.end())
break;
jump_instruction->tag_mappings[constr_pair.second.tag] =
jump_instruction->branches.size();
}
jump_instruction->branches.push_back(std::move(branch_instructions));
} else if((cpat = dynamic_cast<pattern_constr*>(branch->pat.get()))) {
env_ptr new_env = env;
for(auto it = cpat->params.rbegin(); it != cpat->params.rend(); it++) {
new_env = env_ptr(new env_var(branch->expr->env->get_mangled_name(*it), new_env));
}
branch_instructions.push_back(instruction_ptr(new instruction_split(
cpat->params.size())));
branch->expr->compile(new_env, branch_instructions);
branch_instructions.push_back(instruction_ptr(new instruction_slide(
cpat->params.size())));
int new_tag = type->constructors[cpat->constr].tag;
if(jump_instruction->tag_mappings.find(new_tag) !=
jump_instruction->tag_mappings.end())
throw type_error("technically not a type error: duplicate pattern");
jump_instruction->tag_mappings[new_tag] =
jump_instruction->branches.size();
jump_instruction->branches.push_back(std::move(branch_instructions));
}
}
for(auto& constr_pair : type->constructors) {
if(jump_instruction->tag_mappings.find(constr_pair.second.tag) ==
jump_instruction->tag_mappings.end())
throw type_error("non-total pattern");
}
}
void ast_let::print(int indent, std::ostream& to) const {
print_indent(indent, to);
to << "LET: " << std::endl;
in->print(indent + 1, to);
}
void ast_let::find_free(std::set<std::string>& into) {
definitions.find_free(into);
std::set<std::string> all_free;
in->find_free(all_free);
for(auto& free_var : all_free) {
if(definitions.defs_defn.find(free_var) == definitions.defs_defn.end())
into.insert(free_var);
}
}
type_ptr ast_let::typecheck(type_mgr& mgr, type_env_ptr& env) {
this->env = env;
definitions.typecheck(mgr, env);
return in->typecheck(mgr, definitions.env);
}
void ast_let::translate(global_scope& scope) {
for(auto& def : definitions.defs_data) {
def.second->into_globals(scope);
}
for(auto& def : definitions.defs_defn) {
size_t original_params = def.second->params.size();
std::string original_name = def.second->name;
auto& global_definition = def.second->into_global(scope);
size_t captured = global_definition.params.size() - original_params;
type_env_ptr mangled_env = type_scope(env);
mangled_env->bind(def.first, env->lookup(def.first), visibility::global);
mangled_env->set_mangled_name(def.first, global_definition.name);
ast_ptr global_app(new ast_lid(original_name));
global_app->env = mangled_env;
for(auto& param : global_definition.params) {
if(!(captured--)) break;
ast_ptr new_arg(new ast_lid(param));
new_arg->env = env;
global_app = ast_ptr(new ast_app(std::move(global_app), std::move(new_arg)));
global_app->env = env;
}
translated_definitions.push_back({ def.first, std::move(global_app) });
}
in->translate(scope);
}
void ast_let::compile(const env_ptr& env, std::vector<instruction_ptr>& into) const {
into.push_back(instruction_ptr(new instruction_alloc(translated_definitions.size())));
env_ptr new_env = env;
for(auto& def : translated_definitions) {
new_env = env_ptr(new env_var(definitions.env->get_mangled_name(def.first), std::move(new_env)));
}
int offset = translated_definitions.size() - 1;
for(auto& def : translated_definitions) {
def.second->compile(new_env, into);
into.push_back(instruction_ptr(new instruction_update(offset--)));
}
in->compile(new_env, into);
into.push_back(instruction_ptr(new instruction_slide(translated_definitions.size())));
}
void ast_lambda::print(int indent, std::ostream& to) const {
print_indent(indent, to);
to << "LAMBDA";
for(auto& param : params) {
to << " " << param;
}
to << std::endl;
body->print(indent+1, to);
}
void ast_lambda::find_free(std::set<std::string>& into) {
body->find_free(free_variables);
for(auto& param : params) {
free_variables.erase(param);
}
into.insert(free_variables.begin(), free_variables.end());
}
type_ptr ast_lambda::typecheck(type_mgr& mgr, type_env_ptr& env) {
this->env = env;
var_env = type_scope(env);
type_ptr return_type = mgr.new_type();
type_ptr full_type = return_type;
for(auto it = params.rbegin(); it != params.rend(); it++) {
type_ptr param_type = mgr.new_type();
var_env->bind(*it, param_type);
full_type = type_ptr(new type_arr(std::move(param_type), full_type));
}
mgr.unify(return_type, body->typecheck(mgr, var_env));
return full_type;
}
void ast_lambda::translate(global_scope& scope) {
std::vector<std::string> function_params;
for(auto& free_variable : free_variables) {
if(env->is_global(free_variable)) continue;
function_params.push_back(free_variable);
}
size_t captured_count = function_params.size();
function_params.insert(function_params.end(), params.begin(), params.end());
auto& new_function = scope.add_function("lambda", std::move(function_params), std::move(body));
type_env_ptr mangled_env = type_scope(env);
mangled_env->bind("lambda", type_scheme_ptr(nullptr), visibility::global);
mangled_env->set_mangled_name("lambda", new_function.name);
ast_ptr new_application = ast_ptr(new ast_lid("lambda"));
new_application->env = mangled_env;
for(auto& param : new_function.params) {
if(!(captured_count--)) break;
ast_ptr new_arg = ast_ptr(new ast_lid(param));
new_arg->env = env;
new_application = ast_ptr(new ast_app(std::move(new_application), std::move(new_arg)));
new_application->env = env;
}
translated = std::move(new_application);
}
void ast_lambda::compile(const env_ptr& env, std::vector<instruction_ptr>& into) const {
translated->compile(env, into);
}
void pattern_var::print(std::ostream& to) const {
to << var;
}
void pattern_var::find_variables(std::set<std::string>& into) const {
into.insert(var);
}
void pattern_var::typecheck(type_ptr t, type_mgr& mgr, type_env_ptr& env) const {
env->bind(var, t);
}
void pattern_constr::print(std::ostream& to) const {
to << constr;
for(auto& param : params) {
to << " " << param;
}
}
void pattern_constr::find_variables(std::set<std::string>& into) const {
into.insert(params.begin(), params.end());
}
void pattern_constr::typecheck(type_ptr t, type_mgr& mgr, type_env_ptr& env) const {
type_scheme_ptr constructor_type_scheme = env->lookup(constr);
if(!constructor_type_scheme) {
throw type_error(std::string("pattern using unknown constructor ") + constr);
}
type_ptr constructor_type = constructor_type_scheme->instantiate(mgr);
for(auto& param : params) {
type_arr* arr = dynamic_cast<type_arr*>(constructor_type.get());
if(!arr) throw type_error("too many parameters in constructor pattern");
env->bind(param, arr->left);
constructor_type = arr->right;
}
mgr.unify(t, constructor_type);
}