[SYCL][Graph] E2E test for nullptr dynamic parameter update (#15984)

Test for updating a dynamic parameter with a nullptr USM parameter.

Author: EwanC

sycl/test-e2e/Graph/Update/update_nullptr.cpp

@@ -0,0 +1,67 @@
+// RUN: %{build} -o %t.out
+// RUN: %{run} %t.out
+// Extra run to check for leaks in Level Zero using UR_L0_LEAKS_DEBUG
+// RUN: %if level_zero %{env SYCL_PI_LEVEL_ZERO_USE_IMMEDIATE_COMMANDLISTS=0 %{l0_leak_check} %{run} %t.out 2>&1 | FileCheck %s --implicit-check-not=LEAK %}
+// Extra run to check for immediate-command-list in Level Zero
+// RUN: %if level_zero %{env SYCL_PI_LEVEL_ZERO_USE_IMMEDIATE_COMMANDLISTS=1 %{l0_leak_check} %{run} %t.out 2>&1 | FileCheck %s --implicit-check-not=LEAK %}
+
+// Tests updating a graph node using a USM pointer set to nullptr
+
+#include "../graph_common.hpp"
+
+int main() {
+  queue Queue{};
+
+  const size_t N = 1024;
+
+  exp_ext::command_graph Graph{Queue.get_context(), Queue.get_device()};
+
+  int *PtrOut = malloc_device<int>(N, Queue);
+  int *PtrIn = malloc_device<int>(N, Queue);
+
+  Queue.memset(PtrOut, 0, N * sizeof(int)).wait();
+  int PtrPattern = 42;
+  Queue.fill(PtrIn, PtrPattern, N).wait();
+
+  exp_ext::dynamic_parameter InputParam(Graph, PtrIn);
+  int DefaultPattern = 10;
+  auto KernelNode = Graph.add([&](handler &cgh) {
+    cgh.set_arg(0, InputParam);
+    cgh.set_arg(1, PtrOut);
+    cgh.single_task([=]() {
+      for (size_t i = 0; i < N; i++) {
+        if (PtrIn) {
+          PtrOut[i] = PtrIn[i];
+        } else {
+          PtrOut[i] = DefaultPattern;
+        }
+      }
+    });
+  });
+
+  auto ExecGraph = Graph.finalize(exp_ext::property::graph::updatable{});
+
+  // PtrA should be filled with values
+  Queue.ext_oneapi_graph(ExecGraph).wait();
+
+  std::vector<int> HostData(N);
+  Queue.copy(PtrOut, HostData.data(), N).wait();
+  for (size_t i = 0; i < N; i++) {
+    assert(HostData[i] == PtrPattern);
+  }
+
+  // Swap Input to nullptr
+  int *NullPtr = nullptr;
+  InputParam.update(NullPtr);
+  ExecGraph.update(KernelNode);
+  Queue.ext_oneapi_graph(ExecGraph).wait();
+
+  Queue.copy(PtrOut, HostData.data(), N).wait();
+  for (size_t i = 0; i < N; i++) {
+    assert(HostData[i] == DefaultPattern);
+  }
+
+  free(PtrIn, Queue);
+  free(PtrOut, Queue);
+  return 0;
+}