create_var
var = create_var(hist_data, file, field_name, val->size, val->type);
track_var = create_var(hist_data, file, "__max", sizeof(u64), "u64");
track_var = create_var(hist_data, file, "__change", sizeof(u64), "u64");
temp = create_var(long_unsigned_type_node, "temp_latent_entropy");
frame_addr = create_var(ptr_type_node, "local_entropy_frameaddr");
tmp = create_var(long_unsigned_type_node, "temp_latent_entropy");
local_entropy = create_var(long_unsigned_type_node, "local_entropy");