c-compiler/src/codegen.cpp
2026-04-09 17:17:57 +03:00

105 lines
3.4 KiB
C++

#include "codegen.h"
#include "ast.h"
#include <llvm/IR/Module.h>
#include <llvm/IR/Verifier.h>
#include <memory>
#include <iostream>
namespace AST {
llvm::Value* IntLiteralExpression::codegen(codegen::Builder& builder, codegen::Scope& scope) {
auto ty = builder.builder->getInt32Ty();
return llvm::ConstantInt::get(ty, this->m_value);
}
llvm::Value* ValueReferenceExpression::codegen(codegen::Builder& builder, codegen::Scope& scope) {
auto value = scope.values.find(this->m_name);
if (value != scope.values.end()) {
return builder.builder->CreateLoad(value->second.ty, value->second.value);
}
else {
throw new std::runtime_error("Value " + this->m_name + " not found");
}
}
llvm::Value* BinaryOperationExpression::codegen(codegen::Builder& builder, codegen::Scope& scope) {
auto lhs = this->m_lhs->codegen(builder, scope);
auto rhs = this->m_rhs->codegen(builder, scope);
switch (this->m_binop) {
case BinOp::Assignment:
builder.builder->CreateStore(rhs, lhs, false);
return lhs;
default:
throw std::runtime_error("invalid binop");
}
}
void ReturnStatement::codegen(codegen::Builder& builder, codegen::Scope& scope) {
if (!builder.block)
return;
builder.builder->SetInsertPoint(builder.block);
auto value = this->m_expr->codegen(builder, scope);
builder.builder->CreateRet(value);
}
void ExpressionStatement::codegen(codegen::Builder& builder, codegen::Scope& scope) {
if (!builder.block)
return;
builder.builder->SetInsertPoint(builder.block);
this->m_expr->codegen(builder, scope);
}
void InitializationStatement::codegen(codegen::Builder& builder, codegen::Scope& scope) {
if (!builder.block)
return;
builder.builder->SetInsertPoint(builder.block);
auto ty = this->m_type->codegen(builder, scope);
auto ptr = builder.builder->CreateAlloca(ty);
if (this->m_expr.has_value()) {
auto value = this->m_expr->get()->codegen(builder, scope);
builder.builder->CreateStore(value, ptr, false);
}
scope.values[this->m_name] = codegen::StackValue{ ptr, ty };
}
void Function::codegen(codegen::Builder& builder, codegen::Scope& scope) {
codegen::Scope inner_scope{ scope };
auto ret_ty = this->m_return_ty->codegen(builder, inner_scope);
std::vector<llvm::Type*> params{};
auto fn_ty = llvm::FunctionType::get(ret_ty, params, false);
auto function = llvm::Function::Create(
fn_ty,
llvm::GlobalValue::LinkageTypes::ExternalLinkage,
this->m_name,
builder.mod.get()
);
auto BB = llvm::BasicBlock::Create(*builder.context, "entry", function, nullptr);
builder.block = BB;
for (auto& statement : this->m_statements) {
statement->codegen(builder, inner_scope);
}
llvm::verifyFunction(*function);
builder.block = nullptr;
}
llvm::Type* FundamentalType::codegen(codegen::Builder& builder, codegen::Scope& scope) {
switch (this->m_ty) {
case FundamentalTypeKind::Int:
return builder.builder->getInt32Ty();
default:
return builder.builder->getVoidTy();
}
}
}