Revert "[DebugInfo][RemoveDIs] Convert debug-info modes when loading bitcode (#78967)"

This reverts commit 215b8f1e25.

Numerous builders exploded from this X_X, for example

  https://lab.llvm.org/buildbot/#/builders/46/builds/62657

llvm/lib/Bitcode/Reader/BitcodeReader.cpp

@@ -100,9 +100,6 @@ static cl::opt<bool> ExpandConstantExprs(
     cl::desc(
         "Expand constant expressions to instructions for testing purposes"));
 
-// Declare external flag for whether we're using the new debug-info format.
-extern llvm::cl::opt<bool> UseNewDbgInfoFormat;
-
 namespace {
 
 enum {
@@ -6632,9 +6629,6 @@ Error BitcodeReader::materialize(GlobalValue *GV) {
   if (Error Err = materializeMetadata())
     return Err;
 
-  bool NewDebugInfoRequested = F->IsNewDbgInfoFormat;
-  F->IsNewDbgInfoFormat = false;
-
   // Move the bit stream to the saved position of the deferred function body.
   if (Error JumpFailed = Stream.JumpToBit(DFII->second))
     return JumpFailed;
@@ -6710,14 +6704,6 @@ Error BitcodeReader::materialize(GlobalValue *GV) {
   // Look for functions that rely on old function attribute behavior.
   UpgradeFunctionAttributes(*F);
 
-  // If we've materialized a function set up in "new" debug-info mode, the
-  // contents just loaded will still be in dbg.value mode. Switch to the new
-  // mode now. NB: we can add more complicated logic here in the future to
-  // correctly identify when we do and don't need to autoupgrade.
-  if (NewDebugInfoRequested) {
-    F->convertToNewDbgValues();
-  }
-
   // Bring in any functions that this function forward-referenced via
   // blockaddresses.
   return materializeForwardReferencedFunctions();
@@ -8041,15 +8027,6 @@ BitcodeModule::getModuleImpl(LLVMContext &Context, bool MaterializeAll,
     if (Error Err = R->materializeForwardReferencedFunctions())
       return std::move(Err);
   }
-
-  // If we are operating in a "new debug-info" context, upgrade the debug-info
-  // in the loaded module. This is a transitional approach as we enable "new"
-  // debug-info in LLVM, which will eventually be pushed down into the
-  // autoupgrade path once the bitcode-encoding is finalised. Non-materialised
-  // functions will be upgraded in the materialize method.
-  if (UseNewDbgInfoFormat && !M->IsNewDbgInfoFormat)
-    M->convertToNewDbgValues();
-
   return std::move(M);
 }
 

llvm/lib/IR/LegacyPassManager.cpp

@@ -530,8 +530,7 @@ bool PassManagerImpl::run(Module &M) {
 
   // RemoveDIs: if a command line flag is given, convert to the DPValue
   // representation of debug-info for the duration of these passes.
-  bool shouldConvertDbgInfo = UseNewDbgInfoFormat && !M.IsNewDbgInfoFormat;
-  if (shouldConvertDbgInfo)
+  if (UseNewDbgInfoFormat)
     M.convertToNewDbgValues();
 
   for (ImmutablePass *ImPass : getImmutablePasses())
@@ -546,8 +545,7 @@ bool PassManagerImpl::run(Module &M) {
   for (ImmutablePass *ImPass : getImmutablePasses())
     Changed |= ImPass->doFinalization(M);
 
-  if (shouldConvertDbgInfo)
-    M.convertFromNewDbgValues();
+  M.convertFromNewDbgValues();
 
   return Changed;
 }

llvm/lib/Linker/IRMover.cpp

@@ -694,7 +694,6 @@ Function *IRLinker::copyFunctionProto(const Function *SF) {
                              SF->getAddressSpace(), SF->getName(), &DstM);
   F->copyAttributesFrom(SF);
   F->setAttributes(mapAttributeTypes(F->getContext(), F->getAttributes()));
-  F->IsNewDbgInfoFormat = SF->IsNewDbgInfoFormat;
   return F;
 }
 

llvm/lib/Transforms/Utils/ValueMapper.cpp

@@ -1056,13 +1056,9 @@ void Mapper::remapFunction(Function &F) {
       A.mutateType(TypeMapper->remapType(A.getType()));
 
   // Remap the instructions.
-  for (BasicBlock &BB : F) {
-    for (Instruction &I : BB) {
+  for (BasicBlock &BB : F)
+    for (Instruction &I : BB)
       remapInstruction(&I);
-      for (DPValue &DPV : I.DbgMarker->getDbgValueRange())
-        remapDPValue(DPV);
-    }
-  }
 }
 
 void Mapper::mapAppendingVariable(GlobalVariable &GV, Constant *InitPrefix,

llvm/test/LTO/X86/pr38046.ll

@@ -5,14 +5,6 @@
 ; RUN: llvm-dis %t.lto.o.0.2.internalize.bc >/dev/null 2>%t.dis.stderr || true
 ; RUN: FileCheck -allow-empty %s < %t.dis.stderr
 
-;; Re-run with "new" debug-info mode to ensure the variable location information
-;; is handled gracefully.
-; RUN: llvm-lto2 run -save-temps -o %t.lto.o %t.o \
-; RUN:   -r=%t.o,foo,plx \
-; RUN:   -r=%t.o,get,pl --try-experimental-debuginfo-iterators
-; RUN: llvm-dis %t.lto.o.0.2.internalize.bc >/dev/null 2>%t.dis.stderr || true
-; RUN: FileCheck -allow-empty %s < %t.dis.stderr
-
 ; CHECK-NOT: Global is external, but doesn't have external or weak linkage
 
 target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"

llvm/test/Linker/debug-info-use-before-def.ll

@@ -1,5 +1,4 @@
 ; RUN: llvm-link -S %s | FileCheck %s
-; RUN: llvm-link -S %s --try-experimental-debuginfo-iterators | FileCheck %s
 
 ; Test that when a debug metadata use-before-def is run through llvm-link, the
 ; value reference is preserved. Tests both singular uses and DIArgList uses of

llvm/test/Linker/thinlto_funcimport_debug.ll

@@ -6,10 +6,6 @@
 ; If we import func1 and not func2 we should only link DISubprogram for func1
 ; RUN: llvm-link %t2.bc -summary-index=%t3.thinlto.bc -import=func1:%t.bc -S | FileCheck %s
 
-;; Repeat runlines using "new" debuginfo iterators mode.
-; RUN: llvm-lto -thinlto -o %t3 %t.bc %t2.bc --try-experimental-debuginfo-iterators
-; RUN: llvm-link %t2.bc -summary-index=%t3.thinlto.bc -import=func1:%t.bc -S --try-experimental-debuginfo-iterators | FileCheck %s
-
 ; CHECK: declare i32 @func2
 ; CHECK: define available_externally i32 @func1
 

llvm/test/ThinLTO/X86/debuginfo-cu-import.ll

@@ -13,10 +13,6 @@
 ; CHECK-NOT: DICompileUnit{{.*}} globals:
 ; CHECK-NOT: DICompileUnit{{.*}} imports:
 
-;; Repeat test in RemoveDIs debug-info mode to check that bitcode is loaded and
-;; converted correctly.
-; RUN: llvm-lto -thinlto-action=import %t2.bc -thinlto-index=%t.index.bc -o - --try-experimental-debuginfo-iterators | llvm-dis -o - | FileCheck %s
-
 ; ModuleID = 'debuginfo-cu-import.c'
 source_filename = "debuginfo-cu-import.c"
 target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"

llvm/test/ThinLTO/X86/pr35472.ll

@@ -9,12 +9,6 @@
 ; RUN: llvm-nm %t1.bc.thinlto.o | FileCheck %s -check-prefix=ThinLTOa
 ; RUN: llvm-nm %t2.bc.thinlto.o | FileCheck %s -check-prefix=ThinLTOb
 
-;; Re-run with "new" debug-info mode, checking that we load / convert / emit
-;; the dbg.declares below correctly.
-; RUN: llvm-lto -thinlto-action=run %t1.bc %t2.bc -exported-symbol=_Z5Alphav --try-experimental-debuginfo-iterators
-; RUN: llvm-nm %t1.bc.thinlto.o | FileCheck %s -check-prefix=ThinLTOa
-; RUN: llvm-nm %t2.bc.thinlto.o | FileCheck %s -check-prefix=ThinLTOb
-
 ; ThinLTOa-DAG: T _Z5Bravov
 ; ThinLTOa-DAG: W _ZN4EchoD2Ev
 ; ThinLTOb-DAG: T _Z5Alphav

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

@@ -129,13 +129,6 @@ static cl::opt<bool> IgnoreNonBitcode(
     cl::desc("Do not report an error for non-bitcode files in archives"),
     cl::Hidden);
 
-static cl::opt<bool> TryUseNewDbgInfoFormat(
-    "try-experimental-debuginfo-iterators",
-    cl::desc("Enable debuginfo iterator positions, if they're built in"),
-    cl::init(false));
-
-extern cl::opt<bool> UseNewDbgInfoFormat;
-
 static ExitOnError ExitOnErr;
 
 // Read the specified bitcode file in and return it. This routine searches the
@@ -472,17 +465,6 @@ int main(int argc, char **argv) {
   cl::HideUnrelatedOptions({&LinkCategory, &getColorCategory()});
   cl::ParseCommandLineOptions(argc, argv, "llvm linker\n");
 
-  // RemoveDIs debug-info transition: tests may request that we /try/ to use the
-  // new debug-info format, if it's built in.
-#ifdef EXPERIMENTAL_DEBUGINFO_ITERATORS
-  if (TryUseNewDbgInfoFormat) {
-    // If LLVM was built with support for this, turn the new debug-info format
-    // on.
-    UseNewDbgInfoFormat = true;
-  }
-#endif
-  (void)TryUseNewDbgInfoFormat;
-
   LLVMContext Context;
   Context.setDiagnosticHandler(std::make_unique<LLVMLinkDiagnosticHandler>(),
                                true);

llvm/tools/llvm-lto/llvm-lto.cpp

@@ -264,13 +264,6 @@ static cl::opt<bool>
     LTOSaveBeforeOpt("lto-save-before-opt", cl::init(false),
                      cl::desc("Save the IR before running optimizations"));
 
-static cl::opt<bool> TryUseNewDbgInfoFormat(
-    "try-experimental-debuginfo-iterators",
-    cl::desc("Enable debuginfo iterator positions, if they're built in"),
-    cl::init(false), cl::Hidden);
-
-extern cl::opt<bool> UseNewDbgInfoFormat;
-
 namespace {
 
 struct ModuleInfo {
@@ -944,17 +937,6 @@ int main(int argc, char **argv) {
   cl::HideUnrelatedOptions({&LTOCategory, &getColorCategory()});
   cl::ParseCommandLineOptions(argc, argv, "llvm LTO linker\n");
 
-  // RemoveDIs debug-info transition: tests may request that we /try/ to use the
-  // new debug-info format, if it's built in.
-#ifdef EXPERIMENTAL_DEBUGINFO_ITERATORS
-  if (TryUseNewDbgInfoFormat) {
-    // If LLVM was built with support for this, turn the new debug-info format
-    // on.
-    UseNewDbgInfoFormat = true;
-  }
-#endif
-  (void)TryUseNewDbgInfoFormat;
-
   if (OptLevel < '0' || OptLevel > '3')
     error("optimization level must be between 0 and 3");
 

llvm/tools/llvm-lto2/llvm-lto2.cpp

@@ -187,13 +187,6 @@ static cl::opt<bool> EnableFreestanding(
     cl::desc("Enable Freestanding (disable builtins / TLI) during LTO"),
     cl::Hidden);
 
-static cl::opt<bool> TryUseNewDbgInfoFormat(
-    "try-experimental-debuginfo-iterators",
-    cl::desc("Enable debuginfo iterator positions, if they're built in"),
-    cl::init(false), cl::Hidden);
-
-extern cl::opt<bool> UseNewDbgInfoFormat;
-
 static void check(Error E, std::string Msg) {
   if (!E)
     return;
@@ -229,17 +222,6 @@ static int usage() {
 static int run(int argc, char **argv) {
   cl::ParseCommandLineOptions(argc, argv, "Resolution-based LTO test harness");
 
-  // RemoveDIs debug-info transition: tests may request that we /try/ to use the
-  // new debug-info format, if it's built in.
-#ifdef EXPERIMENTAL_DEBUGINFO_ITERATORS
-  if (TryUseNewDbgInfoFormat) {
-    // If LLVM was built with support for this, turn the new debug-info format
-    // on.
-    UseNewDbgInfoFormat = true;
-  }
-#endif
-  (void)TryUseNewDbgInfoFormat;
-
   // FIXME: Workaround PR30396 which means that a symbol can appear
   // more than once if it is defined in module-level assembly and
   // has a GV declaration. We allow (file, symbol) pairs to have multiple