Method CodegenMaterializeExprs

be/src/runtime/tuple.cc:400–504

Codegens an unrolled version of MaterializeExprs(). Uses codegen'd exprs and slot writes. If 'pool' is non-NULL, string data is copied into it. Example IR for materializing a string column with non-NULL 'pool', produced by the following query: select l_comment from tpch.lineitem order by l_comment limit 10; define void @MaterializeExprs(%"class.impala::Tuple"* %opaque_tuple, %"class.impala::Tup

//   ret void
// }
Status Tuple::CodegenMaterializeExprs(LlvmCodeGen* codegen, bool collect_varlen_vals,
    const TupleDescriptor& desc, const vector<ScalarExpr*>& slot_materialize_exprs,
    bool use_mem_pool, llvm::Function** fn) {
  // Only support 'collect_varlen_vals' == false for now.
  // TODO IMPALA-12068: implement it for 'collect_varlen_vals' == true too.
  if (collect_varlen_vals) {
    return Status("CodegenMaterializeExprs() collect_varlen_vals == true NYI");
  }
  llvm::LLVMContext& context = codegen->context();

  // Codegen each compute function from slot_materialize_exprs
  llvm::Function* materialize_expr_fns[slot_materialize_exprs.size()];
  for (int i = 0; i < slot_materialize_exprs.size(); ++i) {
    Status status = slot_materialize_exprs[i]->GetCodegendComputeFn(
        codegen, false, &materialize_expr_fns[i]);
    if (!status.ok()) {
      return Status::Expected(Substitute("Could not codegen CodegenMaterializeExprs: $0",
            status.GetDetail()));
    }
  }

  // Construct function signature (this must exactly match the actual signature since it's
  // used in xcompiled IR). With 'pool':
  // void MaterializeExprs(Tuple* opaque_tuple, TupleRow* row,
  //     const TupleDescriptor& desc, ScalarExprEvaluator* const* evals, MemPool* pool,
  //     CodegenTypes::StringValuePtrVecType* non_null_string_values,
  //     CodegenTypes::CollValuePtrAndSizeVecType* non_null_collection_values,
  //     int* total_varlen_lengths, int* num_non_null_string_values,
  //     int* num_non_null_collection_values);
  llvm::PointerType* opaque_tuple_type = codegen->GetStructPtrType<Tuple>();
  llvm::PointerType* row_type = codegen->GetStructPtrType<TupleRow>();
  llvm::PointerType* desc_type = codegen->GetStructPtrType<TupleDescriptor>();
  llvm::PointerType* expr_evals_type =
      codegen->GetStructPtrPtrType<ScalarExprEvaluator>();
  llvm::PointerType* pool_type = codegen->GetStructPtrType<MemPool>();
  llvm::Type* string_values_type =
      CodegenTypes::getStringValuePtrVecType(codegen)->getPointerTo();
  llvm::Type* coll_values_and_sizes_type =
      CodegenTypes::getCollValuePtrAndSizeVecType(codegen)->getPointerTo();
  llvm::PointerType* int_ptr_type = codegen->i32_ptr_type();

  LlvmCodeGen::FnPrototype prototype(codegen, "MaterializeExprs", codegen->void_type());
  prototype.AddArgument("opaque_tuple", opaque_tuple_type);
  prototype.AddArgument("row", row_type);
  prototype.AddArgument("desc", desc_type);
  prototype.AddArgument("slot_materialize_expr_evals", expr_evals_type);
  prototype.AddArgument("pool", pool_type);
  prototype.AddArgument("non_null_string_values", string_values_type);
  prototype.AddArgument("non_null_collection_values", coll_values_and_sizes_type);
  prototype.AddArgument("total_varlen_lengths", int_ptr_type);
  prototype.AddArgument("num_non_null_string_values", int_ptr_type);
  prototype.AddArgument("num_non_null_collection_values", int_ptr_type);

  LlvmBuilder builder(context);
  llvm::Value* args[10];
  *fn = prototype.GeneratePrototype(&builder, args);
  llvm::Value* opaque_tuple_arg = args[0];
  llvm::Value* row_arg = args[1];