From 9247ed3714abe9ec88e211960ad4200f4459d570 Mon Sep 17 00:00:00 2001
From: Philippe Tillet <ptillet@g.harvard.edu>
Date: Wed, 19 Dec 2018 11:25:29 -0500
Subject: [PATCH] [Code generation]

---
 include/ast.h   | 26 +++++++++++++++++---------
 lib/codegen.cpp | 37 +++++++++++++++++++++++++++----------
 2 files changed, 44 insertions(+), 19 deletions(-)

diff --git a/include/ast.h b/include/ast.h
index a01c20fcc..da14081ab 100644
--- a/include/ast.h
+++ b/include/ast.h
@@ -58,7 +58,7 @@ enum TYPE_T{
 // AST
 class node {
 public:
-  virtual void codegen(module*) { }
+  virtual void codegen(module*) const { }
 };
 
 template<class T>
@@ -71,7 +71,7 @@ public:
     return this;
   }
 
-  void codegen(module* mod)
+  void codegen(module* mod) const
   { for(T x: values_){ x->codegen(mod); } }
 
   const std::list<T> &values() const
@@ -155,14 +155,17 @@ class statement: public node{
 
 };
 
+class initializer;
 class declaration: public node{
 public:
   declaration(node *spec, node *init)
-    : spec_(spec), init_(init) { }
+    : spec_(spec), init_((list<initializer*>*)init) { }
+
+  void codegen(module* mod) const;
 
 public:
   const node *spec_;
-  const node *init_;
+  const list<initializer*> *init_;
 };
 
 
@@ -174,6 +177,8 @@ public:
   compound_statement(node* decls, node* statements)
     : decls_((declarations_t)decls), statements_((statements_t)statements) {}
 
+  virtual void codegen(module* mod) const;
+
 private:
   declarations_t decls_;
   statements_t statements_;
@@ -307,12 +312,15 @@ private:
   llvm::Type* type_impl(module* mod, llvm::Type *type) const;
 
 public:
-  initializer(node *id, node *initializer)
-  : declarator(id), initializer_(initializer){ }
+  initializer(node *decl, node *init)
+  : declarator((node*)((declarator*)decl)->id()),
+    decl_((declarator*)decl), init_(init){ }
 
+  void codegen(module *) const;
 
 public:
-  const node *initializer_;
+  const declarator *decl_;
+  const node *init_;
 };
 
 
@@ -332,7 +340,7 @@ public:
   function_definition(node *spec, node *header, node *body)
     : spec_((declaration_specifier*)spec), header_((function *)header), body_((compound_statement*)body) { }
 
-  void codegen(module* mod);
+  void codegen(module* mod) const;
 
 public:
   const declaration_specifier *spec_;
@@ -351,7 +359,7 @@ public:
     return this;
   }
 
-  void codegen(module* mod);
+  void codegen(module* mod) const;
 
 private:
   list<node*>* decls_;
diff --git a/lib/codegen.cpp b/lib/codegen.cpp
index e5efd686b..6fd528120 100644
--- a/lib/codegen.cpp
+++ b/lib/codegen.cpp
@@ -31,7 +31,7 @@ llvm::IRBuilder<>& module::builder() {
 namespace ast{
 
 /* Translation unit */
-void translation_unit::codegen(module *mod){
+void translation_unit::codegen(module *mod) const{
   decls_->codegen(mod);
 }
 
@@ -78,8 +78,8 @@ Type* tile::type_impl(module*, Type *type) const{
 }
 
 // Initializer
-Type* initializer::type_impl(module *, Type *type) const{
-  return type;
+Type* initializer::type_impl(module *mod, Type *type) const{
+  return decl_->type(mod, type);
 }
 
 // Pointer
@@ -97,14 +97,31 @@ Type* function::type_impl(module*mod, Type *type) const{
 }
 
 /* Function definition */
-void function_definition::codegen(module *mod){
-  llvm::FunctionType *prototype = (llvm::FunctionType *)header_->type(mod, spec_->type(mod));
+void function_definition::codegen(module *mod) const{
+  FunctionType *prototype = (FunctionType *)header_->type(mod, spec_->type(mod));
   const std::string &name = header_->id()->name();
-  llvm::Function *fn = llvm::Function::Create(prototype, llvm::Function::ExternalLinkage, name, mod->handle());
-  llvm::BasicBlock::Create(mod->handle()->getContext(), "entry", fn);
-  mod->builder().SetInsertPoint();
-
-}
+  Function *fn = Function::Create(prototype, Function::ExternalLinkage, name, mod->handle());
+  BasicBlock *entry = BasicBlock::Create(mod->handle()->getContext(), "entry", fn);
+  mod->builder().SetInsertPoint(entry);
+  body_->codegen(mod);
+}
+
+/* Statements */
+void compound_statement::codegen(module* mod) const{
+  decls_->codegen(mod);
+  statements_->codegen(mod);
+}
+
+/* Declaration */
+void declaration::codegen(module* mod) const{
+
+}
+
+/* Initializat */
+void initializer::codegen(module *) const{
+
+}
+
 
 }