refactor: cleanup around IGC library name mocking logic

This patchset improves mocking of IGC library name and adds
safety mechanism to ensure that global IGC library name gets
restored before test finishes.

Related-To: NEO-12747

Signed-off-by: Chodor, Jaroslaw <jaroslaw.chodor@intel.com>

shared/test/common/mocks/CMakeLists.txt

@@ -65,6 +65,7 @@ set(NEO_CORE_tests_mocks
     ${CMAKE_CURRENT_SOURCE_DIR}/mock_gmm_resource_info.h
     ${CMAKE_CURRENT_SOURCE_DIR}/mock_graphics_allocation.h
     ${CMAKE_CURRENT_SOURCE_DIR}/mock_host_ptr_manager.h
+    ${CMAKE_CURRENT_SOURCE_DIR}${BRANCH_DIR_SUFFIX}/mock_igc_path.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/mock_gfx_core_helper.h
     ${CMAKE_CURRENT_SOURCE_DIR}/mock_kmd_notify_helper.h
     ${CMAKE_CURRENT_SOURCE_DIR}/mock_product_helper.cpp

shared/test/common/mocks/mock_compilers.cpp

@@ -70,9 +70,8 @@ void MockCompilerEnableGuard::Enable() {
     if (enabled == false) {
         // load mock from self (don't load dynamic libraries)
         this->oldFclDllName = Os::frontEndDllName;
-        this->oldIgcDllName = Os::igcDllName;
         Os::frontEndDllName = "";
-        Os::igcDllName = "";
+        igcNameGuard = pushIgcDllName("");
         MockCIFMain::setGlobalCreatorFunc<NEO::MockIgcOclDeviceCtx>(NEO::MockIgcOclDeviceCtx::Create);
         MockCIFMain::setGlobalCreatorFunc<NEO::MockFclOclDeviceCtx>(NEO::MockFclOclDeviceCtx::Create);
         if (fclDebugVars == nullptr) {
@@ -89,7 +88,7 @@ void MockCompilerEnableGuard::Enable() {
 void MockCompilerEnableGuard::Disable() {
     if (enabled) {
         Os::frontEndDllName = this->oldFclDllName;
-        Os::igcDllName = this->oldIgcDllName;
+        igcNameGuard.reset();
 
         MockCIFMain::removeGlobalCreatorFunc<NEO::MockIgcOclDeviceCtx>();
         MockCIFMain::removeGlobalCreatorFunc<NEO::MockFclOclDeviceCtx>();

shared/test/common/mocks/mock_compilers.h

@@ -19,6 +19,11 @@
 
 namespace NEO {
 
+struct PopIgcDllNameGuard {
+    ~PopIgcDllNameGuard();
+};
+[[nodiscard]] std::unique_ptr<PopIgcDllNameGuard> pushIgcDllName(const char *name);
+
 struct MockCompilerDebugVars {
     enum class SipAddressingType {
         unknown,
@@ -61,9 +66,9 @@ struct MockCompilerEnableGuard {
     void Disable(); // NOLINT(readability-identifier-naming)
 
     const char *oldFclDllName;
-    const char *oldIgcDllName;
 
     bool enabled = false;
+    std::unique_ptr<PopIgcDllNameGuard> igcNameGuard;
 };
 
 void setFclDebugVars(MockCompilerDebugVars &dbgv);

shared/test/common/mocks/mock_igc_path.cpp

@@ -0,0 +1,41 @@
+/*
+ * Copyright (C) 2024 Intel Corporation
+ *
+ * SPDX-License-Identifier: MIT
+ *
+ */
+
+#include "shared/source/utilities/stackvec.h"
+#include "shared/test/common/mocks/mock_compilers.h"
+
+#include <memory>
+
+namespace Os {
+extern const char *igcDllName;
+} // namespace Os
+
+namespace NEO {
+
+StackVec<const char *, 32> prevIgcDllName;
+
+bool popIgcDllName() {
+    if (prevIgcDllName.empty()) {
+        return false;
+    }
+
+    Os::igcDllName = *prevIgcDllName.rbegin();
+    prevIgcDllName.pop_back();
+    return true;
+}
+
+PopIgcDllNameGuard::~PopIgcDllNameGuard() {
+    popIgcDllName();
+}
+
+[[nodiscard]] std::unique_ptr<PopIgcDllNameGuard> pushIgcDllName(const char *name) {
+    prevIgcDllName.push_back(Os::igcDllName);
+    Os::igcDllName = name;
+    return std::make_unique<PopIgcDllNameGuard>();
+}
+
+} // namespace NEO