root/test/correctness/vectorized_initialization.cpp

DEFINITIONS

1. main

#include "Halide.h"
#include <stdio.h>

using namespace Halide;

int main(int argc, char **argv) {
    // By default, the bounds computed in the initialization step of a
    // reduction cover all uses of the Func by later stages. During
    // lowering, we expand them to cover the bounds read by the update
    // step. We had a bug where we expanded the bounds, but didn't
    // updated the max_min, which meant that vectorized
    // initializations were not being initialized over the full
    // domain. This example tests the fix for that bug.

    Func f, g;
    Var x;
    RDom r(0, 4);

    f(x) = x;
    f(r) = f(r-1) + f(r+1);
    f.compute_root().vectorize(x, 4);
    f.update();

    g(x) = f(x);
    Buffer<int> result = g.realize(4);


    // The sequence generated should be:
    // -1, (-1 + 1) = 0, 0 + 2 = 2, 2 + 3 = 5, 5 + 4 = 9
    if (result(0) != 0 || result(1) != 2 || result(2) != 5 || result(3) != 9) {
        printf("Resulting sequence was: %d %d %d %d instead of 0 2 5 9\n",
               result(0), result(1), result(2), result(3));
        return -1;
    }

    printf("Success\n");
    return 0;
}