source: tests/zombies/vector-perf/iteration-perf.cfa @ cb921d4

#include "vector2.hfa"

#include <time.h>

enum { NumElements = 10000, NumReps = 50000 };

// A layer of indirection to improve performance (naturally!)
// Works around trac #248.
// This test keeps a vector of notfloat, instead of a vector of float.  The optimizer removes this added indirection.
// Furthermore, by passing notfloat's static-inline constructors, defined in this compile unit, to vector, the vector's element's constructors become eligible for inlining.
// Skipping this optimization costs about a 25% slowdown.
struct notfloat{ inline float; };

int main() {
    clock_t start, end;
    vector(notfloat) x = { 4 };
    for (i; NumElements) {
        push_last(x, (notfloat){0.1f * i});
    }
    float total;
    start = clock();
    for (rep; NumReps) {
        total = 0;
        while( vector_exit(notfloat) it = x`origin; it`moveNext ) {
            total += it`val;
        }
    }
    end = clock();
    printf("last total was %f\n", total);
    double elapsed = ((double) (end - start)) / CLOCKS_PER_SEC; \
    printf("iterating duration was %f\n", elapsed);
}