[RemoveDIs] Make verify-uselistorder preserve the input debug info format (#87789)

Verify-uselistorder wants to take some input IR and verify that the
uselist order is stable after roundtripping to bitcode and assembly.
This is disrupted if the file is converted between the new and old debug
info formats after parsing - while there's no functional difference, the
change to the in-memory representation of the IR modifies the uselist.
This patch changes verify-uselistorder to not convert input files
between debug info formats by default, preventing changes from being
made to the file being checked. In addition, this patch makes it so that
when we _do_ print IR in the new debug info format to bitcode or
assembly, we delete any lingering debug intrinsic declarations, ensuring
that we don't write uselist entries for them.

Author: SLTozer

llvm/lib/Bitcode/Writer/BitcodeWriterPass.cpp

@@ -23,6 +23,8 @@ extern bool WriteNewDbgInfoFormatToBitcode;
 PreservedAnalyses BitcodeWriterPass::run(Module &M, ModuleAnalysisManager &AM) {
   ScopedDbgInfoFormatSetter FormatSetter(M, M.IsNewDbgInfoFormat &&
                                                 WriteNewDbgInfoFormatToBitcode);
+  if (M.IsNewDbgInfoFormat)
+    M.removeDebugIntrinsicDeclarations();
 
   const ModuleSummaryIndex *Index =
       EmitSummaryIndex ? &(AM.getResult<ModuleSummaryIndexAnalysis>(M))
@@ -54,6 +56,8 @@ namespace {
     bool runOnModule(Module &M) override {
       ScopedDbgInfoFormatSetter FormatSetter(
           M, M.IsNewDbgInfoFormat && WriteNewDbgInfoFormatToBitcode);
+      if (M.IsNewDbgInfoFormat)
+        M.removeDebugIntrinsicDeclarations();
 
       WriteBitcodeToFile(M, OS, ShouldPreserveUseListOrder, /*Index=*/nullptr,
                          /*EmitModuleHash=*/false);

llvm/lib/Transforms/IPO/ThinLTOBitcodeWriter.cpp

@@ -581,10 +581,10 @@ llvm::ThinLTOBitcodeWriterPass::run(Module &M, ModuleAnalysisManager &AM) {
   FunctionAnalysisManager &FAM =
       AM.getResult<FunctionAnalysisManagerModuleProxy>(M).getManager();
 
-  // RemoveDIs: there's no bitcode representation of the DbgVariableRecord
-  // debug-info, convert to dbg.values before writing out.
   ScopedDbgInfoFormatSetter FormatSetter(M, M.IsNewDbgInfoFormat &&
                                                 WriteNewDbgInfoFormatToBitcode);
+  if (M.IsNewDbgInfoFormat)
+    M.removeDebugIntrinsicDeclarations();
 
   bool Changed = writeThinLTOBitcode(
       OS, ThinLinkOS,

llvm/tools/llvm-as/llvm-as.cpp

@@ -143,8 +143,10 @@ int main(int argc, char **argv) {
 
   // Convert to new debug format if requested.
   assert(!M->IsNewDbgInfoFormat && "Unexpectedly in new debug mode");
-  if (UseNewDbgInfoFormat && WriteNewDbgInfoFormatToBitcode)
+  if (UseNewDbgInfoFormat && WriteNewDbgInfoFormatToBitcode) {
     M->convertToNewDbgValues();
+    M->removeDebugIntrinsicDeclarations();
+  }
 
   std::unique_ptr<ModuleSummaryIndex> Index = std::move(ModuleAndIndex.Index);
 

llvm/tools/llvm-dis/llvm-dis.cpp

@@ -259,6 +259,8 @@ int main(int argc, char **argv) {
       if (!DontPrint) {
         if (M) {
           ScopedDbgInfoFormatSetter FormatSetter(*M, WriteNewDbgInfoFormat);
+          if (WriteNewDbgInfoFormat)
+            M->removeDebugIntrinsicDeclarations();
           M->print(Out->os(), Annotator.get(), PreserveAssemblyUseListOrder);
         }
         if (Index)

llvm/tools/llvm-link/llvm-link.cpp

@@ -136,6 +136,8 @@ static cl::opt<bool> TryUseNewDbgInfoFormat(
 
 extern cl::opt<bool> UseNewDbgInfoFormat;
 extern cl::opt<cl::boolOrDefault> PreserveInputDbgFormat;
+extern cl::opt<bool> WriteNewDbgInfoFormat;
+extern bool WriteNewDbgInfoFormatToBitcode;
 
 extern cl::opt<cl::boolOrDefault> LoadBitcodeIntoNewDbgInfoFormat;
 
@@ -545,10 +547,18 @@ int main(int argc, char **argv) {
 
   if (Verbose)
     errs() << "Writing bitcode...\n";
+  auto SetFormat = [&](bool NewFormat) {
+    Composite->setIsNewDbgInfoFormat(NewFormat);
+    if (NewFormat)
+      Composite->removeDebugIntrinsicDeclarations();
+  };
   if (OutputAssembly) {
+    SetFormat(WriteNewDbgInfoFormat);
     Composite->print(Out.os(), nullptr, PreserveAssemblyUseListOrder);
-  } else if (Force || !CheckBitcodeOutputToConsole(Out.os()))
+  } else if (Force || !CheckBitcodeOutputToConsole(Out.os())) {
+    SetFormat(WriteNewDbgInfoFormatToBitcode);
     WriteBitcodeToFile(*Composite, Out.os(), PreserveBitcodeUseListOrder);
+  }
 
   // Declare success.
   Out.keep();

llvm/tools/verify-uselistorder/verify-uselistorder.cpp

@@ -68,7 +68,7 @@ static cl::opt<unsigned>
                 cl::desc("Number of times to shuffle and verify use-lists"),
                 cl::init(1), cl::cat(Cat));
 
-extern cl::opt<cl::boolOrDefault> LoadBitcodeIntoNewDbgInfoFormat;
+extern cl::opt<cl::boolOrDefault> PreserveInputDbgFormat;
 
 namespace {
 
@@ -169,9 +169,6 @@ std::unique_ptr<Module> TempFile::readBitcode(LLVMContext &Context) const {
     return nullptr;
   }
 
-  // verify-uselistoder currently only supports old-style debug info mode.
-  // FIXME: Update mapping code for RemoveDIs.
-  ModuleOr.get()->setIsNewDbgInfoFormat(false);
   return std::move(ModuleOr.get());
 }
 
@@ -181,9 +178,6 @@ std::unique_ptr<Module> TempFile::readAssembly(LLVMContext &Context) const {
   std::unique_ptr<Module> M = parseAssemblyFile(Filename, Err, Context);
   if (!M.get())
     Err.print("verify-uselistorder", errs());
-  // verify-uselistoder currently only supports old-style debug info mode.
-  // FIXME: Update mapping code for RemoveDIs.
-  M->setIsNewDbgInfoFormat(false);
   return M;
 }
 
@@ -228,8 +222,15 @@ ValueMapping::ValueMapping(const Module &M) {
         map(&I);
 
     // Constants used by instructions.
-    for (const BasicBlock &BB : F)
-      for (const Instruction &I : BB)
+    for (const BasicBlock &BB : F) {
+      for (const Instruction &I : BB) {
+        for (const DbgVariableRecord &DVR :
+             filterDbgVars(I.getDbgRecordRange())) {
+          for (Value *Op : DVR.location_ops())
+            map(Op);
+          if (DVR.isDbgAssign())
+            map(DVR.getAddress());
+        }
         for (const Value *Op : I.operands()) {
           // Look through a metadata wrapper.
           if (const auto *MAV = dyn_cast<MetadataAsValue>(Op))
@@ -240,6 +241,8 @@ ValueMapping::ValueMapping(const Module &M) {
               isa<InlineAsm>(Op))
             map(Op);
         }
+      }
+    }
   }
 }
 
@@ -536,6 +539,7 @@ static void reverseUseLists(Module &M) {
 }
 
 int main(int argc, char **argv) {
+  PreserveInputDbgFormat = cl::boolOrDefault::BOU_TRUE;
   InitLLVM X(argc, argv);
 
   // Enable debug stream buffering.
@@ -545,18 +549,11 @@ int main(int argc, char **argv) {
   cl::ParseCommandLineOptions(argc, argv,
                               "llvm tool to verify use-list order\n");
 
-  // Do not load bitcode into the new debug info format by default.
-  if (LoadBitcodeIntoNewDbgInfoFormat == cl::boolOrDefault::BOU_UNSET)
-    LoadBitcodeIntoNewDbgInfoFormat = cl::boolOrDefault::BOU_FALSE;
-
   LLVMContext Context;
   SMDiagnostic Err;
 
   // Load the input module...
   std::unique_ptr<Module> M = parseIRFile(InputFilename, Err, Context);
-  // verify-uselistoder currently only supports old-style debug info mode.
-  // FIXME: Update mapping code for RemoveDIs.
-  M->setIsNewDbgInfoFormat(false);
 
   if (!M.get()) {
     Err.print(argv[0], errs());