webnn: implement gatherElements for DirectML backend

This CL also adds some WPT conformance tests to verify the
implementation.

webmachinelearning/webnn#375 (comment)

Bug: 40206287
Change-Id: I88e6bbdf1fd6156421d8b190ed6be6d3b216962b
Cq-Include-Trybots: luci.chromium.try:win11-blink-rel, mac14.arm64-blink-rel, mac14-blink-rel, mac15.arm64-blink-rel, mac15-blink-rel, linux-blink-rel
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5811264
Auto-Submit: Shiyi Zou <shiyi.zou@intel.com>
Commit-Queue: Weizhong Xia <weizhong@google.com>
Reviewed-by: ningxin hu <ningxin.hu@intel.com>
Reviewed-by: Weizhong Xia <weizhong@google.com>
Cr-Commit-Position: refs/heads/main@{#1348676}

webnn/conformance_tests/gatherElements.https.any.js

@@ -0,0 +1,142 @@
+// META: title=test WebNN API gatherElements operation
+// META: global=window,dedicatedworker
+// META: variant=?cpu
+// META: variant=?gpu
+// META: variant=?npu
+// META: script=../resources/utils.js
+// META: timeout=long
+
+'use strict';
+
+// https://www.w3.org/TR/webnn/#api-mlgraphbuilder-gatherElements
+// Gather values of the input tensor along an axis according to the indices.
+//
+// dictionary MLGatherOptions {
+//   [EnforceRange] unsigned long axis = 0;
+// };
+//
+// MLOperand gatherElements(
+//     MLOperand input, MLOperand indices,
+//     optional MLGatherOptions options = {});
+
+
+const getGatherElementsPrecisionTolerance = () => {
+  return {metricType: 'ULP', value: 0};
+};
+
+const gatherElementsTests = [
+  {
+    'name': 'gatherElements float32 2D input and uint32 indices options.axis=1',
+    'graph': {
+      'inputs': {
+        'gatherElementsInput': {
+          'data': [
+            -66.05901336669922, -68.9197006225586, -77.02045440673828,
+            -26.158037185668945, 89.0337142944336, -45.89653396606445,
+            43.84803771972656, 48.81806945800781, 51.79948425292969
+          ],
+          'descriptor': {'dimensions': [3, 3], 'dataType': 'float32'}
+        },
+        'gatherElementsIndices': {
+          'data': [1, 0, 2, 2, 1, 0],
+          'descriptor': {'dimensions': [3, 2], 'dataType': 'uint32'},
+          'constant': true
+        }
+      },
+      'operators': [{
+        'name': 'gatherElements',
+        'arguments': [
+          {'input': 'gatherElementsInput'},
+          {'indices': 'gatherElementsIndices'}, {'options': {'axis': 1}}
+        ],
+        'outputs': 'gatherElementsOutput'
+      }],
+      'expectedOutputs': {
+        'gatherElementsOutput': {
+          'data': [
+            -68.9197006225586, -66.05901336669922, -45.89653396606445,
+            -45.89653396606445, 48.81806945800781, 43.84803771972656
+          ],
+          'descriptor': {'dimensions': [3, 2], 'dataType': 'float32'}
+        }
+      }
+    }
+  },
+  {
+    'name': 'gatherElements float32 3D input and int32 negative indices',
+    'graph': {
+      'inputs': {
+        'gatherElementsInput': {
+          'data': [
+            -66.05901336669922, -68.9197006225586, -77.02045440673828,
+            -26.158037185668945, 89.0337142944336, -45.89653396606445,
+            43.84803771972656, 48.81806945800781
+          ],
+          'descriptor': {'dimensions': [2, 2, 2], 'dataType': 'float32'}
+        },
+        'gatherElementsIndices': {
+          'data': [-1, 0, 0, -1],
+          'descriptor': {'dimensions': [1, 2, 2], 'dataType': 'int32'},
+          'constant': true
+        }
+      },
+      'operators': [{
+        'name': 'gatherElements',
+        'arguments': [
+          {'input': 'gatherElementsInput'}, {'indices': 'gatherElementsIndices'}
+        ],
+        'outputs': 'gatherElementsOutput'
+      }],
+      'expectedOutputs': {
+        'gatherElementsOutput': {
+          'data': [
+            89.0337142944336, -68.9197006225586, -77.02045440673828,
+            48.81806945800781
+          ],
+          'descriptor': {'dimensions': [1, 2, 2], 'dataType': 'float32'}
+        }
+      }
+    }
+  },
+  {
+    'name': 'gatherElements float32 1D input and uint32 out-of-bounds indices',
+    'graph': {
+      'inputs': {
+        'gatherElementsInput': {
+          'data': [
+            -26.158037185668945, 89.0337142944336, -45.89653396606445,
+            43.84803771972656, 48.81806945800781, 51.79948425292969
+          ],
+          'descriptor': {'dimensions': [6], 'dataType': 'float32'}
+        },
+        'gatherElementsIndices': {
+          'data': [7],
+          'descriptor': {'dimensions': [1], 'dataType': 'uint32'},
+          'constant': true
+        }
+      },
+      'operators': [{
+        'name': 'gatherElements',
+        'arguments': [
+          {'input': 'gatherElementsInput'}, {'indices': 'gatherElementsIndices'}
+        ],
+        'outputs': 'gatherElementsOutput'
+      }],
+      'expectedOutputs': {
+        'gatherElementsOutput': {
+          'data': [51.79948425292969],
+          'descriptor': {'dimensions': [1], 'dataType': 'float32'}
+        }
+      }
+    }
+  }
+];
+
+if (navigator.ml) {
+  gatherElementsTests.forEach((test) => {
+    webnn_conformance_test(
+        buildGraphAndCompute, getGatherElementsPrecisionTolerance, test);
+  });
+} else {
+  test(() => assert_implements(navigator.ml, 'missing navigator.ml'));
+}