Modified BUILD rules to have a more explicit way to enable XNNPACK delegate by default.

PiperOrigin-RevId: 315635582
Change-Id: Ib0e0c2aa02530923b105972397b00b76cd66c35c

tensorflow/lite/BUILD

@@ -332,10 +332,36 @@ cc_library(
 # Enables applying XNNPACK delegate for float models in TFLite runtime.
 # WARNING: This build flag is experimental and subject to change.
 config_setting(
-    name = "tflite_with_xnnpack_enabled",
+    name = "tflite_with_xnnpack_explicit_true",
     values = {"define": "tflite_with_xnnpack=true"},
 )
 
+config_setting(
+    name = "tflite_with_xnnpack_explicit_false",
+    values = {"define": "tflite_with_xnnpack=false"},
+)
+
+cc_library(
+    name = "tflite_with_xnnpack_enabled",
+    defines = ["TFLITE_BUILD_WITH_XNNPACK_DELEGATE"],
+    visibility = ["//visibility:private"],
+    deps = [
+        "//tensorflow/lite/delegates/xnnpack:xnnpack_delegate",
+    ],
+)
+
+cc_library(
+    name = "tflite_with_xnnpack_default",
+    visibility = ["//visibility:private"],
+    # TODO(b/151246885): put ":tflite_with_xnnpack_enabled" to macos/windows
+    # once we have a good testing coverage on these two platforms.
+    deps = select({
+        "//tensorflow:macos": [],
+        "//tensorflow:windows": [],
+        "//conditions:default": [],
+    }),
+)
+
 cc_library(
     name = "tflite_with_xnnpack_optional",
     srcs = ["tflite_with_xnnpack_optional.cc"],
@@ -344,17 +370,18 @@ cc_library(
         "tflite_with_xnnpack_optional.h",
     ],
     copts = tflite_copts() + TFLITE_DEFAULT_COPTS,
-    defines = select({
-        ":tflite_with_xnnpack_enabled": ["TFLITE_BUILD_WITH_XNNPACK_DELEGATE"],
-        "//conditions:default": [],
-    }),
     deps = [
         "//tensorflow/lite/c:common",
     ] + select({
-        ":tflite_with_xnnpack_enabled": [
+        ":tflite_with_xnnpack_explicit_true": [
-            "//tensorflow/lite/delegates/xnnpack:xnnpack_delegate",
+            "//tensorflow/lite/delegates/xnnpack:xnnpack_delegate_hdrs_only",
+            ":tflite_with_xnnpack_enabled",
+        ],
+        ":tflite_with_xnnpack_explicit_false": [],
+        "//conditions:default": [
+            "//tensorflow/lite/delegates/xnnpack:xnnpack_delegate_hdrs_only",
+            ":tflite_with_xnnpack_default",
         ],
-        "//conditions:default": [],
     }),
 )
 

tensorflow/lite/delegates/xnnpack/BUILD

@@ -29,6 +29,15 @@ cc_library(
     ],
 )
 
+cc_library(
+    name = "xnnpack_delegate_hdrs_only",
+    hdrs = ["xnnpack_delegate.h"],
+    visibility = ["//tensorflow/lite:__subpackages__"],
+    deps = [
+        "//tensorflow/lite/c:common",
+    ],
+)
+
 cc_library(
     name = "xnnpack_delegate_test_mode",
     srcs = ["xnnpack_delegate.cc"],

tensorflow/lite/model_xnnpack_test.cc

@@ -36,7 +36,7 @@ TEST(FloatModel, WithXnnpackDelegate) {
 
   ASSERT_EQ(interpreter->AllocateTensors(), kTfLiteOk);
 
-#if TFLITE_HAS_ATTRIBUTE_WEAK
+#if TFLITE_HAS_ATTRIBUTE_WEAK || defined(TFLITE_BUILD_WITH_XNNPACK_DELEGATE)
   // As the graph is fully delegated by XNNPACK delegate, we will expect the
   // following:
   EXPECT_EQ(1, interpreter->execution_plan().size());