Revert "[DebugInfo][RemoveDIs] Don't pointlessly scan funcs for debug-info (#79327)"

This reverts commit c23608b.

It looks like this depends on #79345, which isn't going to land today, so revert for now.

Author: jmorse

llvm/include/llvm/IR/BasicBlock.h

@@ -81,16 +81,12 @@ class BasicBlock final : public Value, // Basic blocks are data objects also
   /// intrinsics into DPMarker / DPValue records. Deletes all dbg.values in
   /// the process and sets IsNewDbgInfoFormat = true. Only takes effect if
   /// the UseNewDbgInfoFormat LLVM command line option is given.
-  /// \param HasNoDebugInfo Flag indicating the scan of instructions should be
-  /// skipped as the function is known to have no debug-info.
-  void convertToNewDbgValues(bool HasNoDebugInfo = false);
+  void convertToNewDbgValues();
 
   /// Convert variable location debugging information stored in DPMarkers and
   /// DPValues into the dbg.value intrinsic representation. Sets
   /// IsNewDbgInfoFormat = false.
-  /// \param HasNoDebugInfo Flag indicating the scan of instructions should be
-  /// skipped as the function is known to have no debug-info.
-  void convertFromNewDbgValues(bool HasNoDebugInfo = false);
+  void convertFromNewDbgValues();
 
   /// Ensure the block is in "old" dbg.value format (\p NewFlag == false) or
   /// in the new format (\p NewFlag == true), converting to the desired format

llvm/lib/IR/BasicBlock.cpp

@@ -60,17 +60,13 @@ DPMarker *BasicBlock::createMarker(InstListType::iterator It) {
   return DPM;
 }
 
-void BasicBlock::convertToNewDbgValues(bool HasNoDebugInfo) {
+void BasicBlock::convertToNewDbgValues() {
   // Is the command line option set?
   if (!UseNewDbgInfoFormat)
     return;
 
   IsNewDbgInfoFormat = true;
 
-  // If the caller knows there's no debug-info in this function, do nothing.
-  if (HasNoDebugInfo)
-    return;
-
   // Iterate over all instructions in the instruction list, collecting dbg.value
   // instructions and converting them to DPValues. Once we find a "real"
   // instruction, attach all those DPValues to a DPMarker in that instruction.
@@ -97,14 +93,10 @@ void BasicBlock::convertToNewDbgValues(bool HasNoDebugInfo) {
   }
 }
 
-void BasicBlock::convertFromNewDbgValues(bool HasNoDebugInfo) {
+void BasicBlock::convertFromNewDbgValues() {
   invalidateOrders();
   IsNewDbgInfoFormat = false;
 
-  // If the caller knows there's no debug-info in this function, do nothing.
-  if (HasNoDebugInfo)
-    return;
-
   // Iterate over the block, finding instructions annotated with DPMarkers.
   // Convert any attached DPValues to dbg.values and insert ahead of the
   // instruction.

llvm/lib/IR/Function.cpp

@@ -83,17 +83,15 @@ static cl::opt<unsigned> NonGlobalValueMaxNameSize(
 
 void Function::convertToNewDbgValues() {
   IsNewDbgInfoFormat = true;
-  bool HasNoDebugInfo = getSubprogram() == nullptr;
   for (auto &BB : *this) {
-    BB.convertToNewDbgValues(HasNoDebugInfo);
+    BB.convertToNewDbgValues();
   }
 }
 
 void Function::convertFromNewDbgValues() {
   IsNewDbgInfoFormat = false;
-  bool HasNoDebugInfo = getSubprogram() == nullptr;
   for (auto &BB : *this) {
-    BB.convertFromNewDbgValues(HasNoDebugInfo);
+    BB.convertFromNewDbgValues();
   }
 }