h6. [[OS SWI Calls]] h6(. » [[OS_Module]] h6((. » OS_Module 6 h2. OS_ Module 6 h5. (SWI &1E) |_<^{width:4em}. Entry | | |<^. R0 |<^. 6 | |<^. R3 |<^. Size of area | |_<^{width:4em}. Exit | | |<^. R0 |<^. Preserved | |<^. R2 |<^. Block | |<^. R3 |<^. Preserved | h4. Use The purpose of this call is to return an area of free RMA claimed for use. h4. Notes Starting with RISC OS 2.01, memory allocated by this call will have a start address of (n MOD 16)=4. This can be used to help to improve performance by allowing programmers to easily align their code/data to cache-line boundaries (assuming a 16 byte cache line size). In RISC OS 5.00 the alignment was changed to (n MOD 32)=20, which can be useful for machines with 32 byte cache lines. OS_Module 24 can be used to allocate a "naturally aligned" block at an arbitrary power of two alignment (i.e. (n MOD x)=0). h4. See also * [[OS_Module]] * [[OS_Module 24]]