[clang] Fix amdgpu-arch for dll name on Windows (PR #101350)

[Matt Arsenault via cfe-commits]

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@@ -31,16 +44,118 @@ typedef hipError_t (*hipGetDeviceCount_t)(int *);
 typedef hipError_t (*hipDeviceGet_t)(int *, int);
 typedef hipError_t (*hipGetDeviceProperties_t)(hipDeviceProp_t *, int);
 
-int printGPUsByHIP() {
+extern cl::opt<bool> Verbose;
+
 #ifdef _WIN32
-  constexpr const char *DynamicHIPPath = "amdhip64.dll";
+static std::vector<std::string> getSearchPaths() {
+  std::vector<std::string> Paths;
+
+  // Get the directory of the current executable
+  if (auto MainExe = sys::fs::getMainExecutable(nullptr, nullptr);
+      !MainExe.empty())
+    Paths.push_back(sys::path::parent_path(MainExe).str());
+
+  // Get the system directory
+  wchar_t SystemDirectory[MAX_PATH];
+  if (GetSystemDirectoryW(SystemDirectory, MAX_PATH) > 0) {
+    std::string Utf8SystemDir;
+    if (convertUTF16ToUTF8String(
+            ArrayRef<UTF16>(reinterpret_cast<const UTF16 *>(SystemDirectory),
+                            wcslen(SystemDirectory)),
+            Utf8SystemDir))
+      Paths.push_back(Utf8SystemDir);
+  }
+
+  // Get the Windows directory
+  wchar_t WindowsDirectory[MAX_PATH];
+  if (GetWindowsDirectoryW(WindowsDirectory, MAX_PATH) > 0) {
+    std::string Utf8WindowsDir;
+    if (convertUTF16ToUTF8String(
+            ArrayRef<UTF16>(reinterpret_cast<const UTF16 *>(WindowsDirectory),
+                            wcslen(WindowsDirectory)),
+            Utf8WindowsDir))
+      Paths.push_back(Utf8WindowsDir);
+  }
+
+  // Get the current working directory
+  SmallVector<char, 256> CWD;
+  if (sys::fs::current_path(CWD))
+    Paths.push_back(std::string(CWD.begin(), CWD.end()));
+
+  // Get the PATH environment variable
+  if (auto PathEnv = sys::Process::GetEnv("PATH")) {
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arsenm wrote:

No auto 

https://github.com/llvm/llvm-project/pull/101350