TMS320F28388D: Automatic Section Splitting & 'Place each function in a separate subsection' option.

Sang-il Nam said:

When using 'Automatic Section Splitting' to split and place sections in multiple memory regions, is it better to turn on the 'Place each function in a separate subsection (--gen_func_subsections, -mo)' option?

While there is no guarantee, it is likely that turning this option on uses less memory.  There are two ways that can happen.

One .. A split may only occur on an input section boundary.  That is how the tools guarantee a function (or array, or struct, etc.) is never split across different memory ranges.  When each function is in its own section, there are many more input sections of smaller size, and that usually tends to pack better across multiple memory ranges.

Two ... When each function is in its own section, the linker removes the ones which are never called.  Note this occurs independent of section splitting.

Thanks and regards,

-George