i'm writing a small program to print a polygon with printf("\219") to just see if whatever i'm doing is right for my kernel. but it needs to call many functions and i don't know whether x86 processors can accept that many subroutines and i can't find results in google. so my question is will it accept so many function calls and what is the maximum. (i mean something like this:-)
function a() {b();}
function b() {c();}
function c() {d();}
...
i've used 5 such levels (you know what i mean, right?)
Your function depth is not limited by the processor, but by the size of your stack. Behind the scenes, calls to C++ functions usually translate to call instructions in x86, which push four (or eight, for x64 programs) bytes onto your program's stack for the return pointer. Sometimes calls are optimized and don't touch the stack at all. Functions might also push additional bytes (e.g. local function state) onto the stack.
To get the exact number of functions you can call, you need to disassemble your code to calculate the number of bytes each function pushes to the stack (minimum four/eight because of the return address, but likely many more), then find the maximum stack size and divide it by the function frame size.