AsmPrinter + BTFDebug

Author: jansvoboda11

llvm/include/llvm/CodeGen/AsmPrinter.h

@@ -110,9 +110,6 @@ class LLVM_ABI AsmPrinter : public MachineFunctionPass {
   /// generating (such as the current section etc).
   std::unique_ptr<MCStreamer> OutStreamer;
 
-  /// The VFS to resolve asm include directives.
-  IntrusiveRefCntPtr<vfs::FileSystem> VFS;
-
   /// The current machine function.
   MachineFunction *MF = nullptr;
 

llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp

@@ -477,7 +477,6 @@ void AsmPrinter::getAnalysisUsage(AnalysisUsage &AU) const {
 }
 
 bool AsmPrinter::doInitialization(Module &M) {
-  VFS = vfs::getRealFileSystem();
   auto *MMIWP = getAnalysisIfAvailable<MachineModuleInfoWrapperPass>();
   MMI = MMIWP ? &MMIWP->getMMI() : nullptr;
   HasSplitStack = false;

llvm/lib/CodeGen/AsmPrinter/AsmPrinterInlineAsm.cpp

@@ -98,8 +98,13 @@ void AsmPrinter::emitInlineAsm(StringRef Str, const MCSubtargetInfo &STI,
 
   unsigned BufNum = addInlineAsmDiagBuffer(Str, LocMDNode);
   SourceMgr &SrcMgr = *MMI->getContext().getInlineSourceManager();
-  SrcMgr.setIncludeDirs(MCOptions.IASSearchPaths);
-  SrcMgr.setVirtualFileSystem(VFS);
+  // FIXME(sandboxing): This is not executed in tests, but might be common.
+  //                    Propagating vfs::FileSystem here is lots of work,
+  //                    consider bypassing the sandbox.
+  if (!MCOptions.IASSearchPaths.empty()) {
+    SrcMgr.setIncludeDirs(MCOptions.IASSearchPaths);
+    SrcMgr.setVirtualFileSystem(vfs::getRealFileSystem());
+  }
 
   std::unique_ptr<MCAsmParser> Parser(
       createMCAsmParser(SrcMgr, OutContext, *OutStreamer, *MAI, BufNum));

llvm/lib/Target/BPF/BTFDebug.cpp

@@ -23,6 +23,7 @@
 #include "llvm/MC/MCObjectFileInfo.h"
 #include "llvm/MC/MCSectionELF.h"
 #include "llvm/MC/MCStreamer.h"
+#include "llvm/Support/IOSandbox.h"
 #include "llvm/Support/LineIterator.h"
 #include "llvm/Support/MemoryBuffer.h"
 #include "llvm/Target/TargetLoweringObjectFile.h"
@@ -1017,12 +1018,17 @@ std::string BTFDebug::populateFileContent(const DIFile *File) {
   std::string Line;
   Content.push_back(Line); // Line 0 for empty string
 
+  auto LoadFile = [](StringRef FileName) {
+    // FIXME(sandboxing): Propagating vfs::FileSystem here is lots of work.
+    [[maybe_unused]] auto BypassSandbox = sys::sandbox::scopedDisable();
+    return MemoryBuffer::getFile(FileName);
+  };
+
   std::unique_ptr<MemoryBuffer> Buf;
   auto Source = File->getSource();
   if (Source)
     Buf = MemoryBuffer::getMemBufferCopy(*Source);
-  else if (ErrorOr<std::unique_ptr<MemoryBuffer>> BufOrErr =
-               MemoryBuffer::getFile(FileName))
+  else if (ErrorOr<std::unique_ptr<MemoryBuffer>> BufOrErr = LoadFile(FileName))
     Buf = std::move(*BufOrErr);
   if (Buf)
     for (line_iterator I(*Buf, false), E; I != E; ++I)