[llvm] [Offload][Tests] Non-contiguous_update_to_tests (PR #169623)

[Saiyedul Islam via llvm-commits]

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@@ -0,0 +1,72 @@
+// This test checks that #pragma omp target update to(data[0:4:3]) correctly
+// updates every third element (stride 3) from the host to the device, partially
+// across the array
+
+// RUN: %libomptarget-compile-run-and-check-generic
+#include <omp.h>
+#include <stdio.h>
+
+int main() {
+  int len = 11;
+  double data[len];
+
+  // Initialize on host
+  for (int i = 0; i < len; i++)
+    data[i] = i;
+
+  // Initial values
+  printf("original host array values:\n");
+  for (int i = 0; i < len; i++)
+    printf("%f\n", data[i]);
+  printf("\n");
+
+  // CHECK: 0.000000
+  // CHECK: 1.000000
+  // CHECK: 2.000000
+  // CHECK: 3.000000
+  // CHECK: 4.000000
+  // CHECK: 5.000000
+  // CHECK: 6.000000
+  // CHECK: 7.000000
+  // CHECK: 8.000000
+  // CHECK: 9.000000
+  // CHECK: 10.000000
+
+#pragma omp target data map(tofrom : data[0 : len])
+  {
+    // Initialize device array to 20
+#pragma omp target
+    for (int i = 0; i < len; i++)
+      data[i] = 20.0;
+
+    // Modify host data for strided elements
+    data[0] = 10.0;
+    data[3] = 10.0;
+    data[6] = 10.0;
+    data[9] = 10.0;
+
+#pragma omp target update to(data[0 : 4 : 3]) // indices 0,3,6,9
+
+    // Verify on device by adding 5
+#pragma omp target
+    for (int i = 0; i < len; i++)
+      data[i] += 5.0;
+  }
+
+  printf("device array values after update to:\n");
+  for (int i = 0; i < len; i++)
+    printf("%f\n", data[i]);
+  printf("\n");
+
+  // CHECK: 15.000000
+  // CHECK: 25.000000
+  // CHECK: 25.000000
+  // CHECK: 15.000000
+  // CHECK: 25.000000
+  // CHECK: 25.000000
+  // CHECK: 15.000000
+  // CHECK: 25.000000
+  // CHECK: 25.000000
+  // CHECK: 15.000000
+  // CHECK: 25.000000
+}
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saiislam wrote:

Add last line please

https://github.com/llvm/llvm-project/pull/169623