pspsdk | An open-source SDK for PSP homebrew development

Intercepting an instruction that writes to a particular address is not a normal activity in programs.

It is a feature provided by some debuggers. There are at least three ways debuggers may be able to do this:

• A debugger can examine the program code and find where a particular instruction writes to a particular address. This is actually a hugely complicated activity that requires interpreting the instructions. Often, a debugger cannot do it completely; as doing so in general is equivalent to completely interpreting and executing the program the same way the computer processor does, and it is very slow to do in software. Instead, the debugger may plan part of program execution and put in a breakpoint at a spot where it is unable to easily continue, such as at a branch instruction that depends on a value the debugger is not prepared to compute. A breakpoint is a special instruction that interrupts program execution and, in this case, results in the operating system transferring control to the debugger. At that time, the debugger removes the breakpoint, requests that the instruction be single-stepped (that the processor execute the single instruction and then interrupt program execution immediately), examines the result, and continues.
• A debugger can mark the page of memory containing the desired address as no-access. Then, whenever the program accesses that memory, the hardware will interrupt program execution, and the operating system will transfer control to the debugger. The debugger examines the instruction that caused the interruption. If the instruction is accessing the target address, the debugger acts on that. If it is not, the debugger changes the memory protection to allow access, requests that the instruction be single-stepped, changes the memory protection to disallow access, and resumes the program to wait for the next interruption. (Instead of single-stepping the instruction, the debugger might just emulate it, since that might avoid changing the memory protection twice, which can be expensive.)
• Some computer processor models have features to support this sort of debugging feature. The debugger can request that a portion of memory be monitored, so that the hardware interrupts program execution when a particular address is accessed, instead of when any part of a whole memory page is accessed.

I cannot speak to the Sony platform you are using. You would have to check its documentation or ask others regarding the availability of such features. Since this is a feature most often used by debuggers, investigating the documentation regarding debugging could be a way to find out whether the system supports such a feature.

The . (dot) refers to the current directory. Therefore these options are specifying that the current directory should be searched for any required header files (-I.) and any required libraries (-L.).

From the GCC manual: