turbolist/TurboList.hpp

#ifndef TURBO_LIST_H
#define TURBO_LIST_H

#include<cstdint>
#include<cstdlib>
#include<cassert>

#ifndef TL_NOINLINE
#define TL_NOINLINE __attribute__((noinline))
#endif /* TL_NOINLINE */

#ifndef TL_LIKELY
#define TL_LIKELY(x) __builtin_expect(!!(x), 1)
#endif /* TL_LIKELY */
#ifndef TL_UNLIKELY
#define TL_UNLIKELY(x) __builtin_expect(!!(x), 0)
#endif /* TL_UNLIKELY */

class TurboList {
	int *old;
	int *nex;

	uint32_t mid; // non-inclusive . . . m
	uint32_t end; // non-inclusive     e . . . .

	uint32_t capacity;

	TL_NOINLINE void grow_and_insert(int elem) noexcept {
			// assert(mid == 0);
			if(old) free(old);
			old = nex;
			mid = end;
			capacity *= 2;
			nex = (int *) malloc(this->capacity * sizeof(int));

			// Will go into the INSERT code path here
			insert(elem);
	}

public:
	inline TurboList(uint32_t initial_cap = 16) noexcept :
			old(nullptr),
			mid(0),
			end(0),
			capacity(initial_cap) {

		nex = (int *) malloc(this->capacity * sizeof(int));
	}

	inline ~TurboList() noexcept {
		if(nex) free(nex);
		if(old) free(old);
	}

	inline int& operator[](uint32_t i) noexcept {
		return (i < mid) ? old[i] : nex[i];
	}

	inline void insert(int elem) noexcept {
		if(TL_LIKELY(size() < capacity)) {
			// INSERT

			/* Same as this:
			if(mid > 0) {
				nex[mid - 1] = old[mid - 1];
				--mid;
			}
			*/
			bool hasmid = (mid > 0);
			mid -= hasmid;
			nex[mid] = hasmid ? old[mid] : nex[mid];

			nex[end++] = elem;
		} else {
			// GROW

			grow_and_insert(elem);
		}
	}

	inline uint32_t size() noexcept {
		return mid + (capacity - end - 1);
	}
};

#endif /* TURBO_LIST_H */