[clang] [llvm] [Clang] Add env var for nvptx-arch/amdgpu-arch timeout (PR #102521)

[via cfe-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-clang

Author: Joel E. Denny (jdenny-ornl)

<details>
<summary>Changes</summary>

When working on very busy systems, check-offload frequently fails many tests with this diagnostic:

```
clang: error: cannot determine amdgcn architecture: /tmp/llvm/build/bin/amdgpu-arch: Child timed out: ; consider passing it via '-march'
```

The timeout is 10 seconds.  This patch accepts the environment variable `CLANG_TOOL_CHAIN_PROGRAM_WAIT` to increase it.

It should be documented somewhere.  Any suggestions on where?

---
Full diff: https://github.com/llvm/llvm-project/pull/102521.diff


4 Files Affected:

- (modified) clang/lib/Driver/ToolChain.cpp (+9-1) 
- (modified) clang/lib/Driver/ToolChains/AMDGPU.cpp (+2-1) 
- (modified) clang/lib/Driver/ToolChains/Cuda.cpp (+2-1) 
- (modified) llvm/utils/lit/lit/TestingConfig.py (+1) 


``````````diff
diff --git a/clang/lib/Driver/ToolChain.cpp b/clang/lib/Driver/ToolChain.cpp
index 2d50c2cbbc881c..04b281e1bb10cd 100644
--- a/clang/lib/Driver/ToolChain.cpp
+++ b/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 +117,13 @@ 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;
+  }
   if (llvm::sys::ExecuteAndWait(Executable, {}, {}, Redirects, SecondsToWait,
                                 /*MemoryLimit=*/0, &ErrorMessage))
     return llvm::createStringError(std::error_code(),
diff --git a/clang/lib/Driver/ToolChains/AMDGPU.cpp b/clang/lib/Driver/ToolChains/AMDGPU.cpp
index aa8f9197cfabc3..4ed366d21f5c43 100644
--- a/clang/lib/Driver/ToolChains/AMDGPU.cpp
+++ b/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();
 
diff --git a/clang/lib/Driver/ToolChains/Cuda.cpp b/clang/lib/Driver/ToolChains/Cuda.cpp
index 17c952c808f725..104217eaf5d849 100644
--- a/clang/lib/Driver/ToolChains/Cuda.cpp
+++ b/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();
 
diff --git a/llvm/utils/lit/lit/TestingConfig.py b/llvm/utils/lit/lit/TestingConfig.py
index eb9f8de2a7f960..06713429d06b4b 100644
--- a/llvm/utils/lit/lit/TestingConfig.py
+++ b/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",

``````````

</details>


https://github.com/llvm/llvm-project/pull/102521