root/test/correctness/named_updates.cpp

DEFINITIONS

1. main

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

using namespace Halide;

int main(int argc, char **argv) {

    // Test various possible pieces of syntax for tracking the various
    // definitions of a Func. Mostly we just want to make sure they
    // compile. We restrict ourselves to not using C++11 for now,
    // though uniform initializer syntax opens some new possibilities.
    RDom r(0, 16);

    Func f;
    Var x;
    Func ref;

    {

        Stage pure =
            f(x) = x;

        Stage fix_first =
            f(0) = 1;

        Stage rewrites[] = {
            f(r*2) = 13,
            f(r*4) = 14
        };

        struct {
            Stage a, b, c;
        } more_updates = {
            f(3*r) = 4,
            f(2*r) = 8,
            f(5*r) = 2
        };

        f.compute_root();

        pure.vectorize(x, 4);
        rewrites[0].parallel(r);
        rewrites[1].vectorize(r, 4);
        more_updates.a.vectorize(r, 4);
        more_updates.b.vectorize(r, 4);
        more_updates.c.vectorize(r, 4);
    }

    // Define the same thing without all the weird syntax and without
    // any scheduling.
    {
        ref(x) = x;
        ref(0) = 1;
        ref(r*2) = 13;
        ref(r*4) = 14;
        ref(3*r) = 4;
        ref(2*r) = 8;
        ref(5*r) = 2;
    }

    Buffer<int> result = f.realize(128);
    Buffer<int> result_ref = ref.realize(128);

    RDom check(result);
    uint32_t error = evaluate<uint32_t>(
        maximum(abs(result(check) - result_ref(check))));

    if (error) {
        printf("There was a difference between using named updates and not.\n");
        return -1;
    }

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