[clang] [clang-repl] Fix destructor for interpreter for the cuda negation case (PR #138091)

[via cfe-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-clang

Author: Anutosh Bhat (anutosh491)

<details>
<summary>Changes</summary>

Check this error for more context (https://github.com/compiler-research/CppInterOp/actions/runs/14749797085/job/41407625681?pr=491#step:10:531)

This fails with 
```
* thread #<!-- -->1, name = 'CppInterOpTests', stop reason = signal SIGSEGV: address not mapped to object (fault address: 0x55500356d6d3)
  * frame #<!-- -->0: 0x00007fffee41cfe3 libclangCppInterOp.so.21.0gitclang::PragmaNamespace::~PragmaNamespace() + 99
    frame #<!-- -->1: 0x00007fffee435666 libclangCppInterOp.so.21.0gitclang::Preprocessor::~Preprocessor() + 3830
    frame #<!-- -->2: 0x00007fffee20917a libclangCppInterOp.so.21.0gitstd::_Sp_counted_base<(__gnu_cxx::_Lock_policy)2>::_M_release() + 58
    frame #<!-- -->3: 0x00007fffee224796 libclangCppInterOp.so.21.0gitclang::CompilerInstance::~CompilerInstance() + 838
    frame #<!-- -->4: 0x00007fffee22494d libclangCppInterOp.so.21.0gitclang::CompilerInstance::~CompilerInstance() + 13
    frame #<!-- -->5: 0x00007fffed95ec62 libclangCppInterOp.so.21.0gitclang::IncrementalCUDADeviceParser::~IncrementalCUDADeviceParser() + 98
    frame #<!-- -->6: 0x00007fffed9551b6 libclangCppInterOp.so.21.0gitclang::Interpreter::~Interpreter() + 102
    frame #<!-- -->7: 0x00007fffed95598d libclangCppInterOp.so.21.0gitclang::Interpreter::~Interpreter() + 13
    frame #<!-- -->8: 0x00007fffed9181e7 libclangCppInterOp.so.21.0gitcompat::createClangInterpreter(std::vector<char const*, std::allocator<char const*>>&) + 2919
```

Problem : 

1) The destructor currently handles no clearance for the DeviceParser and the DeviceAct. We currently only have this 
https://github.com/llvm/llvm-project/blob/976493822443c52a71ed3c67aaca9a555b20c55d/clang/lib/Interpreter/Interpreter.cpp#L416-L419

2) The ownership for DeviceCI currently is present in IncrementalCudaDeviceParser. But this should be similar to how the combination for hostCI, hostAction and hostParser are managed by the Interpreter. As on master the DeviceAct and DeviceParser are managed by the Interpreter but not DeviceCI.  This is problematic because :
IncrementalParser holds a Sema& which points into the DeviceCI. On master, DeviceCI is destroyed before the base class ~IncrementalParser() runs, causing Parser::reset() to access a dangling Sema (and as Sema holds a reference to Preprocessor which owns PragmaNamespace) we see this 
```
  * frame #<!-- -->0: 0x00007fffee41cfe3 libclangCppInterOp.so.21.0gitclang::PragmaNamespace::~PragmaNamespace() + 99
    frame #<!-- -->1: 0x00007fffee435666 libclangCppInterOp.so.21.0gitclang::Preprocessor::~Preprocessor() + 3830
    
```


---
Full diff: https://github.com/llvm/llvm-project/pull/138091.diff


4 Files Affected:

- (modified) clang/include/clang/Interpreter/Interpreter.h (+3) 
- (modified) clang/lib/Interpreter/DeviceOffload.cpp (+3-4) 
- (modified) clang/lib/Interpreter/DeviceOffload.h (+1-2) 
- (modified) clang/lib/Interpreter/Interpreter.cpp (+7-1) 


``````````diff
diff --git a/clang/include/clang/Interpreter/Interpreter.h b/clang/include/clang/Interpreter/Interpreter.h
index 56213f88b9e30..f8663e3193a18 100644
--- a/clang/include/clang/Interpreter/Interpreter.h
+++ b/clang/include/clang/Interpreter/Interpreter.h
@@ -116,6 +116,9 @@ class Interpreter {
   /// Compiler instance performing the incremental compilation.
   std::unique_ptr<CompilerInstance> CI;
 
+  /// An optional compiler instance for CUDA offloading
+  std::unique_ptr<CompilerInstance> DeviceCI;
+
 protected:
   // Derived classes can use an extended interface of the Interpreter.
   Interpreter(std::unique_ptr<CompilerInstance> Instance, llvm::Error &Err,
diff --git a/clang/lib/Interpreter/DeviceOffload.cpp b/clang/lib/Interpreter/DeviceOffload.cpp
index 7d0125403ea52..8ab6a61993972 100644
--- a/clang/lib/Interpreter/DeviceOffload.cpp
+++ b/clang/lib/Interpreter/DeviceOffload.cpp
@@ -25,13 +25,13 @@
 namespace clang {
 
 IncrementalCUDADeviceParser::IncrementalCUDADeviceParser(
-    std::unique_ptr<CompilerInstance> DeviceInstance,
+    CompilerInstance &DeviceInstance,
     CompilerInstance &HostInstance,
     llvm::IntrusiveRefCntPtr<llvm::vfs::InMemoryFileSystem> FS,
     llvm::Error &Err, const std::list<PartialTranslationUnit> &PTUs)
-    : IncrementalParser(*DeviceInstance, Err), PTUs(PTUs), VFS(FS),
+    : IncrementalParser(DeviceInstance, Err), PTUs(PTUs), VFS(FS),
       CodeGenOpts(HostInstance.getCodeGenOpts()),
-      TargetOpts(DeviceInstance->getTargetOpts()) {
+      TargetOpts(DeviceInstance.getTargetOpts()) {
   if (Err)
     return;
   StringRef Arch = TargetOpts.CPU;
@@ -41,7 +41,6 @@ IncrementalCUDADeviceParser::IncrementalCUDADeviceParser(
                                                llvm::inconvertibleErrorCode()));
     return;
   }
-  DeviceCI = std::move(DeviceInstance);
 }
 
 llvm::Expected<llvm::StringRef> IncrementalCUDADeviceParser::GeneratePTX() {
diff --git a/clang/lib/Interpreter/DeviceOffload.h b/clang/lib/Interpreter/DeviceOffload.h
index 43645033c4840..c1cb4cd23a4b5 100644
--- a/clang/lib/Interpreter/DeviceOffload.h
+++ b/clang/lib/Interpreter/DeviceOffload.h
@@ -28,7 +28,7 @@ class IncrementalCUDADeviceParser : public IncrementalParser {
 
 public:
   IncrementalCUDADeviceParser(
-      std::unique_ptr<CompilerInstance> DeviceInstance,
+      CompilerInstance &DeviceInstance,
       CompilerInstance &HostInstance,
       llvm::IntrusiveRefCntPtr<llvm::vfs::InMemoryFileSystem> VFS,
       llvm::Error &Err, const std::list<PartialTranslationUnit> &PTUs);
@@ -42,7 +42,6 @@ class IncrementalCUDADeviceParser : public IncrementalParser {
   ~IncrementalCUDADeviceParser();
 
 protected:
-  std::unique_ptr<CompilerInstance> DeviceCI;
   int SMVersion;
   llvm::SmallString<1024> PTXCode;
   llvm::SmallVector<char, 1024> FatbinContent;
diff --git a/clang/lib/Interpreter/Interpreter.cpp b/clang/lib/Interpreter/Interpreter.cpp
index 80487eb4ef74a..4ca12f6858c9d 100644
--- a/clang/lib/Interpreter/Interpreter.cpp
+++ b/clang/lib/Interpreter/Interpreter.cpp
@@ -416,6 +416,10 @@ Interpreter::Interpreter(std::unique_ptr<CompilerInstance> Instance,
 Interpreter::~Interpreter() {
   IncrParser.reset();
   Act->FinalizeAction();
+  if (DeviceParser)
+    DeviceParser.reset();
+  if (DeviceAct)
+    DeviceAct->FinalizeAction();
   if (IncrExecutor) {
     if (llvm::Error Err = IncrExecutor->cleanUp())
       llvm::report_fatal_error(
@@ -501,8 +505,10 @@ Interpreter::createWithCUDA(std::unique_ptr<CompilerInstance> CI,
 
   DCI->ExecuteAction(*Interp->DeviceAct);
 
+  Interp->DeviceCI = std::move(DCI);
+
   auto DeviceParser = std::make_unique<IncrementalCUDADeviceParser>(
-      std::move(DCI), *Interp->getCompilerInstance(), IMVFS, Err, Interp->PTUs);
+    *Interp->DeviceCI, *Interp->getCompilerInstance(), IMVFS, Err, Interp->PTUs);
 
   if (Err)
     return std::move(Err);

``````````

</details>


https://github.com/llvm/llvm-project/pull/138091