Global initialized variables which are small in size are stored in this area. The threshold for deciding the size of the variable to be stored in the small data area is set to 8 bytes in the MicroBlaze C compiler (mb-gcc), but this can be changed by giving a command line option to the compiler. Details about this option are discussed in the “GNU Compiler Tools” chapter of the Vitis Unified Software Platform Documentation: Embedded Software Development (UG1400). 64 kilobytes of memory is allocated for the small data areas. The small data area is accessed using the read-write small data area anchor (R13) and a 16-bit offset. Allocating small variables to this area reduces the requirement of adding IMM instructions to the code for accessing global variables. Any variable in the small data area can also be accessed using an absolute address.