[Clang] Add env var for nvptx-arch/amdgpu-arch timeout

clang/include/clang/Basic/DiagnosticDriverKinds.td

@@ -99,7 +99,8 @@ def warn_drv_amdgpu_cov6: Warning<
   " use at your own risk">;
 def err_drv_undetermined_gpu_arch : Error<
   "cannot determine %0 architecture: %1; consider passing it via "
-  "'%2'">;
+  "'%2' or increasing the tool timeout using the environment variable "
+  "'CLANG_TOOL_CHAIN_PROGRAM_WAIT' (in secs, <=0 is inifinite)">;
 def warn_drv_multi_gpu_arch : Warning<
   "multiple %0 architectures are detected: %1; only the first one is used for "
   "'%2'">, InGroup<MultiGPU>;

clang/lib/Driver/ToolChain.cpp

@@ -40,6 +40,7 @@
 #include "llvm/Support/FileSystem.h"
 #include "llvm/Support/FileUtilities.h"
 #include "llvm/Support/Path.h"
+#include "llvm/Support/Process.h"
 #include "llvm/Support/VersionTuple.h"
 #include "llvm/Support/VirtualFileSystem.h"
 #include "llvm/TargetParser/AArch64TargetParser.h"
@@ -105,7 +106,7 @@ ToolChain::ToolChain(const Driver &D, const llvm::Triple &T,
 
 llvm::Expected<std::unique_ptr<llvm::MemoryBuffer>>
 ToolChain::executeToolChainProgram(StringRef Executable,
-                                   unsigned SecondsToWait) const {
+                                   unsigned DefaultSecondsToWait) const {
   llvm::SmallString<64> OutputFile;
   llvm::sys::fs::createTemporaryFile("toolchain-program", "txt", OutputFile);
   llvm::FileRemover OutputRemover(OutputFile.c_str());
@@ -116,6 +117,15 @@ ToolChain::executeToolChainProgram(StringRef Executable,
   };
 
   std::string ErrorMessage;
+  int SecondsToWait = DefaultSecondsToWait;
+  if (std::optional<std::string> Str =
+          llvm::sys::Process::GetEnv("CLANG_TOOL_CHAIN_PROGRAM_WAIT")) {
+    int Val = std::atoi(Str->c_str());
+    if (Val > 0)
+      SecondsToWait = Val;
+    else
+      SecondsToWait = 0; // infinite
+  }
   if (llvm::sys::ExecuteAndWait(Executable, {}, {}, Redirects, SecondsToWait,
                                 /*MemoryLimit=*/0, &ErrorMessage))
     return llvm::createStringError(std::error_code(),

clang/lib/Driver/ToolChains/AMDGPU.cpp

@@ -899,7 +899,8 @@ AMDGPUToolChain::getSystemGPUArchs(const ArgList &Args) const {
   else
     Program = GetProgramPath("amdgpu-arch");
 
-  auto StdoutOrErr = executeToolChainProgram(Program, /*SecondsToWait=*/10);
+  auto StdoutOrErr = executeToolChainProgram(Program,
+                                             /*DefaultSecondsToWait=*/10);
   if (!StdoutOrErr)
     return StdoutOrErr.takeError();
 

clang/lib/Driver/ToolChains/Cuda.cpp

@@ -804,7 +804,8 @@ NVPTXToolChain::getSystemGPUArchs(const ArgList &Args) const {
   else
     Program = GetProgramPath("nvptx-arch");
 
-  auto StdoutOrErr = executeToolChainProgram(Program, /*SecondsToWait=*/10);
+  auto StdoutOrErr = executeToolChainProgram(Program,
+                                             /*DefaultSecondsToWait=*/10);
   if (!StdoutOrErr)
     return StdoutOrErr.takeError();
 

llvm/utils/lit/lit/TestingConfig.py

@@ -26,6 +26,7 @@ def fromdefaults(litConfig):
             "SYSTEMROOT",
             "TERM",
             "CLANG",
+            "CLANG_TOOL_CHAIN_PROGRAM_WAIT",
             "LLDB",
             "LD_PRELOAD",
             "LLVM_SYMBOLIZER_PATH",