[NPUW] Add initial unpack and partitioning unit tests on NPUW (#25780)

This PR adds unit tests on
1) unpack routines within NPUW
2) main online partitioning functionality (smaller unit tests on
`Graph`, `Group`, `Repeated`, etc will be added separately)

Local run:
```
[----------] Global test environment tear-down
[==========] 334 tests from 6 test suites ran. (3379 ms total)
[  PASSED  ] 334 tests.
```

src/plugins/intel_npu/src/plugin/npuw/partitioning/online/snapshot.hpp

@@ -16,8 +16,6 @@ namespace ov {
 namespace npuw {
 namespace online {
 
-class Group;  // forward declaration
-
 namespace detail {
 // At partitioning level we exclude some "non-Ops" to not interfere with the passes.
 // We include some of them back to properly link everything at plugin level
@@ -33,6 +31,8 @@ class Snapshot : public std::enable_shared_from_this<Snapshot> {
           m_node_to_prod_cons(std::make_shared<detail::OVNodeMap>()),
           m_node_to_gr(std::make_shared<detail::OVNodeToGroupMap>()) {}
 
+    friend class Group;  // forward declaration
+
     // Simple passes
     void singleGroup();
 
@@ -49,27 +49,27 @@ class Snapshot : public std::enable_shared_from_this<Snapshot> {
     void repeatedBlocks();
     void earlyAvoids();
     void earlyRegroup();
-    void markInternalCompute();
-    void resetExcludedRep();
 
     // Utility
     std::shared_ptr<own::ade::Graph> getGraph() const;
-    size_t graphSize() const;
-    const detail::OVNodeSet& getNodeProducers(const detail::OVNodePtr& node) const;
-    const detail::OVNodeSet& getNodeConsumers(const detail::OVNodePtr& node) const;
     const detail::OVPortsMap& getPortsMap() const;
     const detail::OVNodeToGroupMapPtr& getNodeToGroupMap() const;
     const std::map<std::string, std::vector<std::set<std::string>>>& getMatches() const;
-    detail::GPtrSet getRepGroups(const std::shared_ptr<Group>& group) const;
     void repeat(detail::Pass&& pass);
     void setCtx(const PassContext& ctx);
+    size_t graphSize() const;
 
 private:
+    detail::GPtrSet getRepGroups(const std::shared_ptr<Group>& group) const;
+    const detail::OVNodeSet& getNodeProducers(const detail::OVNodePtr& node) const;
+    const detail::OVNodeSet& getNodeConsumers(const detail::OVNodePtr& node) const;
     void identifyUniques();
     void mergeUniques();
     void mergeTriangles();
     void cleanUpUniques();
     void afterUniques();
+    void markInternalCompute();
+    void resetExcludedRep();
     bool cleanUpUniquesImpl(const detail::GPtrSet& gset);
     std::shared_ptr<Repeated> tryGrowRepeatingGroups(const detail::GPtrSet& repeating_groups);
     std::shared_ptr<Repeated> tryMergeTriangles(const detail::GPtrSet& repeating_groups);

src/plugins/intel_npu/tests/CMakeLists.txt

@@ -8,3 +8,4 @@ if (MSVC)
     ov_add_compiler_flags(/wd5105)
 endif()
 add_subdirectory(functional)
+add_subdirectory(unit)

src/plugins/intel_npu/tests/unit/CMakeLists.txt

@@ -0,0 +1,49 @@
+# Copyright (C) 2024 Intel Corporation
+# SPDX-License-Identifier: Apache-2.0
+#
+
+set(TARGET_NAME "ov_npu_unit_tests")
+
+set(MANDATORY_UNIT_TESTS_LIBS
+        "openvino::commonTestUtils"
+        "openvino::gmock"
+        "openvino::gtest"
+        "openvino::gtest_main"
+        "openvino::runtime"
+        "openvino::npu_al"
+        "openvino::npu_logger_utils"
+)
+
+ov_add_test_target(
+        NAME ${TARGET_NAME}
+        ROOT ${CMAKE_CURRENT_SOURCE_DIR}
+        ADDITIONAL_SOURCE_DIRS
+            ${OpenVINO_SOURCE_DIR}/src/plugins/intel_npu/src/plugin/npuw/
+        DEPENDENCIES
+            openvino::runtime
+        INCLUDES
+            ${CMAKE_CURRENT_SOURCE_DIR}
+            ${CMAKE_CURRENT_SOURCE_DIR}/npuw
+            ${OpenVINO_SOURCE_DIR}/src/plugins/intel_npu/src/plugin/npuw
+            ${OpenVINO_SOURCE_DIR}/src/plugins/intel_npu/src/utils/include
+            ${OpenVINO_SOURCE_DIR}/src/plugins/intel_npu/src/plugin/include
+            ${OpenVINO_SOURCE_DIR}/src/plugins/intel_npu/src/al/include
+        LINK_LIBRARIES
+            ${MANDATORY_UNIT_TESTS_LIBS}
+        LABELS
+            NPUW
+)
+
+if(CMAKE_CXX_COMPILER_ID MATCHES "Clang" OR CMAKE_CXX_COMPILER_ID MATCHES "GNU")
+    target_compile_options(${TARGET_NAME} PRIVATE -mavx2 -mf16c)
+elseif(CMAKE_CXX_COMPILER_ID MATCHES "MSVC")
+    target_compile_options(${TARGET_NAME} PRIVATE /arch:AVX2)
+else()
+    message(AUTHOR_WARNING "Unknown compiler, may miss the AVX2 baseline setting")
+endif()
+
+install(TARGETS ${TARGET_NAME}
+        RUNTIME DESTINATION tests
+        COMPONENT tests
+        EXCLUDE_FROM_ALL
+)