I was trying to reverse engineer some psp programs developed using the free pspsdk
https://sourceforge.net/projects/minpspw/
I noticed that i created a function to see how MIPS handles more than 4 arguments (a0-a4). Everyone i know has told me that they get passed onto the stack. To my surprise, that 5th argument was actually passed to register t0 and to compiler didn't even use the stack!
it also inlined a function without even having used a jal or jump to it. (obvious optimization). Altough there was indeed a space a memory and you could double check by using print with function pointer argument. That actual code that was executed was automatically inlined without the need of a function call instruction.
^^ but that doesn't really benefit me for a reverse engineer attempt...
there is a man page for this version of gcc. and it takes seconds to install if anyone is able to provide it's man for compilation if there is one. It's so long i don't even know how to reference information reliably