test to follow up on recent fix intel/llvm#7589. Test performs a reduction using sycl::vec<float>. Is sensitive to byte size vs. vector size fix in SYCL headers.

Author: cperkinsintel

SYCL/GroupAlgorithm/SYCL2020/reduce_over_group_size.cpp

@@ -0,0 +1,109 @@
+// RUN: %clangxx -fsycl -fsycl-targets=%sycl_triple %s  -o %t.out
+// RUN: %CPU_RUN_PLACEHOLDER %t.out
+// RUN: %GPU_RUN_PLACEHOLDER %t.out
+// RUN: %ACC_RUN_PLACEHOLDER %t.out
+
+// RUN: %clangxx -fsycl -fsycl-targets=%sycl_triple -O0 %s -o %t_O0.out
+// RUN: %CPU_RUN_PLACEHOLDER %t_O0.out
+// RUN: %GPU_RUN_PLACEHOLDER %t_O0.out
+// RUN: %ACC_RUN_PLACEHOLDER %t_O0.out
+
+/*
+    test performs a lattice reduction.
+    sycl::vec<float> is sensitive to .get_size() vs .size() in SYCL headers
+    (ie, byte size versus vector size)
+*/
+
+#include <sycl/sycl.hpp>
+
+using namespace sycl;
+
+#define NX 32
+#define NZ 2
+#define NV 8
+
+template <typename T>
+void groupSum(T *r, const T &in, const int k, sycl::group<2> &grp,
+              const int i) {
+
+  T tin = (i == k ? in : T(0));
+  auto out = reduce_over_group(grp, tin, sycl::plus<>());
+  if (i == k && grp.get_local_id()[1] == 0)
+    r[k] = out;
+}
+
+void test(queue q, float *r, float *x,
+          int n) { // r is 16 floats, x is 256 floats. n is 256
+
+  sycl::range<2> globalSize(NZ, NX); // 2,32
+  sycl::range<2> localSize(1, NX);   // 1,8       so 16 iterations
+  sycl::nd_range<2> range{globalSize, localSize};
+
+  q.submit([&](sycl::handler &h) {
+    h.parallel_for<>(range, [=](sycl::nd_item<2> ndi) {
+      int i = ndi.get_global_id(1);
+      int k = ndi.get_global_id(0);
+
+      using vecn = sycl::vec<float, NV>; // 8 floats
+      auto vx = reinterpret_cast<vecn *>(x);
+      auto vr = reinterpret_cast<vecn *>(r);
+
+      auto myg = ndi.get_group();
+
+      for (int iz = 0; iz < NZ; iz++) { // loop over Z (2)
+        groupSum(vr, vx[k * NX + i], k, myg, iz);
+      }
+    });
+  });
+  q.wait();
+}
+
+int main() {
+
+  queue q{default_selector_v};
+  auto dev = q.get_device();
+  std::cout << "Device: " << dev.get_info<info::device::name>() << std::endl;
+
+  auto ctx = q.get_context();
+  int n = NX * NZ * NV; // 16 * 8 * 2 => 256
+  auto *x = (float *)sycl::malloc_shared(n * sizeof(float), dev,
+                                         ctx); // 256 * sizeof(float)
+  auto *r = (float *)sycl::malloc_shared(
+      NZ * NV * sizeof(float), dev, ctx); // 2 * 8 => 16   ( * sizeof(float) )
+
+  for (int i = 0; i < n; i++) {
+    x[i] = i;
+  }
+
+  q.wait();
+
+  test(q, r, x, n);
+
+  int fails = 0;
+  for (int k = 0; k < NZ; k++) {
+    float s[NV] = {0};
+    for (int i = 0; i < NX; i++) {
+      for (int j = 0; j < NV; j++) {
+        s[j] += x[(k * NX + i) * NV + j];
+      }
+    }
+    for (int j = 0; j < NV; j++) {
+      auto d = s[j] - r[k * NV + j];
+      if (abs(d) > 1e-10) {
+        printf("partial fail ");
+        printf("%i\t%i\t%g\t%g\n", k, j, s[j], r[k * NV + j]);
+        fails++;
+      } else {
+        printf("partial pass ");
+        printf("%i\t%i\t%g\t%g\n", k, j, s[j], r[k * NV + j]);
+      }
+    }
+  }
+
+  if (fails == 0) {
+    printf("test passed!\n");
+  } else {
+    printf("test failed!\n");
+  }
+  assert(fails == 0);
+}