remove wstring for simplicity

Author: bob80905

include/dxc/Support/dxcapi.extval.h

@@ -8,14 +8,14 @@ class DxcDllExtValidationSupport : public dxc::DxcDllSupport {
 protected:
   dxc::DxcDllSupport DxilSupport;
 
-  std::wstring DxilDllPath;
+  std::string DxilDllPath;
 
   // override DxcDllSupport's implementation of InitializeInternal,
   // adding the environment variable value check for a path to a dxil.dll
   HRESULT InitializeInternal(LPCSTR dllName, LPCSTR fnName) override;
 
 public:
-  std::wstring GetDxilDllPath() { return DxilDllPath; }
+  std::string GetDxilDllPath() { return DxilDllPath; }
   bool DxilDllFailedToLoad() {
     return !DxilDllPath.empty() && !DxilSupport.IsEnabled();
   }

lib/DxcSupport/dxcapi.extval.cpp

@@ -2,9 +2,7 @@
 #include <dxc/Support/Global.h> // for hresult handling with DXC_FAILED
 #include <filesystem>           // C++17 and later
 // WinIncludes must come before dxcapi.extval.h
-#include "dxc/Support/Unicode.h" // for wstring conversions like WideToUtf8String
 #include "dxc/Support/dxcapi.extval.h"
-#include <wchar.h> // for _wgetenv
 
 HRESULT DxcDllExtValidationSupport::InitializeInternal(LPCSTR dllName,
                                                        LPCSTR fnName) {
@@ -16,17 +14,14 @@ HRESULT DxcDllExtValidationSupport::InitializeInternal(LPCSTR dllName,
   }
 
   // now handle external dxil.dll
-  const wchar_t *EnvVarValue = _wgetenv(L"DXC_DXIL_DLL_PATH");
-  if (!EnvVarValue || std::wstring(EnvVarValue).empty()) {
+  const char *EnvVarVal = std::getenv("DXC_DXIL_DLL_PATH");
+  if (!EnvVarVal || std::string(EnvVarVal).empty()) {
     return S_OK;
   }
 
-  std::wstring DllPathWStr(EnvVarValue);
-  std::string DllPathStr;
-  Unicode::WideToUTF8String(DllPathWStr.data(), &DllPathStr);
-
-  DxilDllPath = DllPathWStr;
-  std::filesystem::path DllPath(DllPathWStr);
+  std::string DllPathStr(EnvVarVal);
+  DxilDllPath = DllPathStr;
+  std::filesystem::path DllPath(DllPathStr);
 
   // Check if path is absolute and exists
   if (!DllPath.is_absolute() || !std::filesystem::exists(DllPath)) {
@@ -36,7 +31,6 @@ HRESULT DxcDllExtValidationSupport::InitializeInternal(LPCSTR dllName,
   // to see if dxil.dll is successfully loaded.
   // the CheckDxilDLLLoaded function can determine whether there were any
   // problems loading dxil.dll or not
-
   DxilSupport.InitializeForDll(DllPathStr.data(), fnName);
 
   return S_OK;

tools/clang/unittests/HLSL/ValidationTest.cpp

@@ -4268,7 +4268,7 @@ TEST_F(ValidationTest, UnitTestExtValidationSupport) {
   VERIFY_SUCCEEDED(ExtSupportEmpty.Initialize());
 
   VERIFY_IS_FALSE(ExtSupportEmpty.DxilDllFailedToLoad());
-  VERIFY_ARE_EQUAL_WSTR(ExtSupportEmpty.GetDxilDllPath().c_str(), L"");
+  VERIFY_ARE_EQUAL_STR(ExtSupportEmpty.GetDxilDllPath().c_str(), "");
 
   // 2. Test with a bogus path in the environment variable
   SetEnvVarW(L"DXC_DXIL_DLL_PATH", L"bogus");
@@ -4279,7 +4279,7 @@ TEST_F(ValidationTest, UnitTestExtValidationSupport) {
 
   // validate that m_dllExtSupport2 was able to capture the environment
   // variable's value, and that loading the bogus path was unsuccessful
-  VERIFY_ARE_EQUAL_WSTR(ExtSupportBogus.GetDxilDllPath().c_str(), L"bogus");
+  VERIFY_ARE_EQUAL_STR(ExtSupportBogus.GetDxilDllPath().c_str(), "bogus");
   VERIFY_IS_TRUE(ExtSupportBogus.DxilDllFailedToLoad());
 
   // 3. Test production of class IDs CLSID_DxcCompiler, CLSID_DxcLinker,