// 声明翻译模块：
// - 处理全局变量与局部变量声明
// - 处理数组初始化、空间分配与初值生成等

#include "irgen/IRGen.h"

#include <memory>
#include <stdexcept>

#include "ast/AstNodes.h"
#include "ir/IR.h"

void IRGenImpl::GenBlock(const ast::Block& block) {
  // 先为所有局部变量创建栈槽，使 alloca 聚集在入口块前部。
  for (const auto& decl : block.varDecls) {
    auto* slot = builder_.CreateAllocaI32(ir::DefaultContext().NextTemp());
    locals_[decl->name] = slot;
  }

  for (const auto& decl : block.varDecls) {
    GenVarDecl(*decl);
  }
  for (const auto& stmt : block.stmts) {
    GenStmt(*stmt);
  }
}

void IRGenImpl::GenVarDecl(const ast::VarDecl& decl) {
  auto it = locals_.find(decl.name);
  if (it == locals_.end()) {
    throw std::runtime_error("变量栈槽未创建: " + decl.name);
  }

  ir::Value* init = nullptr;
  if (decl.init) {
    init = GenExpr(*decl.init);
  } else {
    init = ir::DefaultContext().GetConstInt(0);
  }
  builder_.CreateStore(init, it->second);
}