Reapply [RemoveDIs] Enable DPLabels conversion [3b/3] (#82639)

Enables conversion between llvm.dbg.label and DPLabel.

Author: OCHyams

llvm/include/llvm/IR/DebugProgramInstruction.h

@@ -62,6 +62,8 @@ class BasicBlock;
 class MDNode;
 class Module;
 class DbgVariableIntrinsic;
+class DbgInfoIntrinsic;
+class DbgLabelInst;
 class DIAssignID;
 class DPMarker;
 class DPValue;
@@ -80,6 +82,7 @@ class raw_ostream;
 ///   clone
 ///   isIdenticalToWhenDefined
 ///   both print methods
+///   createDebugIntrinsic
 class DbgRecord : public ilist_node<DbgRecord> {
 public:
   /// Marker that this DbgRecord is linked into.
@@ -103,6 +106,11 @@ class DbgRecord : public ilist_node<DbgRecord> {
   void print(raw_ostream &O, bool IsForDebug = false) const;
   void print(raw_ostream &O, ModuleSlotTracker &MST, bool IsForDebug) const;
   bool isIdenticalToWhenDefined(const DbgRecord &R) const;
+  /// Convert this DbgRecord back into an appropriate llvm.dbg.* intrinsic.
+  /// \p InsertBefore Optional position to insert this intrinsic.
+  /// \returns A new llvm.dbg.* intrinsic representiung this DbgRecord.
+  DbgInfoIntrinsic *createDebugIntrinsic(Module *M,
+                                         Instruction *InsertBefore) const;
   ///@}
 
   /// Same as isIdenticalToWhenDefined but checks DebugLoc too.
@@ -177,6 +185,8 @@ class DPLabel : public DbgRecord {
   DPLabel *clone() const;
   void print(raw_ostream &O, bool IsForDebug = false) const;
   void print(raw_ostream &ROS, ModuleSlotTracker &MST, bool IsForDebug) const;
+  DbgLabelInst *createDebugIntrinsic(Module *M,
+                                     Instruction *InsertBefore) const;
 
   void setLabel(DILabel *NewLabel) { Label = NewLabel; }
   DILabel *getLabel() const { return Label; }

llvm/lib/IR/BasicBlock.cpp

@@ -81,6 +81,12 @@ void BasicBlock::convertToNewDbgValues() {
       continue;
     }
 
+    if (DbgLabelInst *DLI = dyn_cast<DbgLabelInst>(&I)) {
+      DPVals.push_back(new DPLabel(DLI->getLabel(), DLI->getDebugLoc()));
+      DLI->eraseFromParent();
+      continue;
+    }
+
     if (DPVals.empty())
       continue;
 
@@ -107,16 +113,12 @@ void BasicBlock::convertFromNewDbgValues() {
       continue;
 
     DPMarker &Marker = *Inst.DbgMarker;
-    for (DbgRecord &DR : Marker.getDbgValueRange()) {
-      if (auto *DPV = dyn_cast<DPValue>(&DR))
-        InstList.insert(Inst.getIterator(),
-                        DPV->createDebugIntrinsic(getModule(), nullptr));
-      else
-        llvm_unreachable("unsupported DbgRecord kind");
-    }
+    for (DbgRecord &DR : Marker.getDbgValueRange())
+      InstList.insert(Inst.getIterator(),
+                      DR.createDebugIntrinsic(getModule(), nullptr));
 
     Marker.eraseFromParent();
-  };
+  }
 
   // Assume no trailing DPValues: we could technically create them at the end
   // of the block, after a terminator, but this would be non-cannonical and

llvm/lib/IR/DebugProgramInstruction.cpp

@@ -112,6 +112,17 @@ bool DbgRecord::isEquivalentTo(const DbgRecord &R) const {
   return getDebugLoc() == R.getDebugLoc() && isIdenticalToWhenDefined(R);
 }
 
+DbgInfoIntrinsic *
+DbgRecord::createDebugIntrinsic(Module *M, Instruction *InsertBefore) const {
+  switch (RecordKind) {
+  case ValueKind:
+    return cast<DPValue>(this)->createDebugIntrinsic(M, InsertBefore);
+  case LabelKind:
+    return cast<DPLabel>(this)->createDebugIntrinsic(M, InsertBefore);
+  };
+  llvm_unreachable("unsupported DbgRecord kind");
+}
+
 DPValue *DPValue::createDPValue(Value *Location, DILocalVariable *DV,
                                 DIExpression *Expr, const DILocation *DI) {
   return new DPValue(ValueAsMetadata::get(Location), DV, Expr, DI,
@@ -377,6 +388,20 @@ DPValue::createDebugIntrinsic(Module *M, Instruction *InsertBefore) const {
   return DVI;
 }
 
+DbgLabelInst *DPLabel::createDebugIntrinsic(Module *M,
+                                            Instruction *InsertBefore) const {
+  auto *LabelFn = Intrinsic::getDeclaration(M, Intrinsic::dbg_label);
+  Value *Args[] = {
+      MetadataAsValue::get(getDebugLoc()->getContext(), getLabel())};
+  DbgLabelInst *DbgLabel = cast<DbgLabelInst>(
+      CallInst::Create(LabelFn->getFunctionType(), LabelFn, Args));
+  DbgLabel->setTailCall();
+  DbgLabel->setDebugLoc(getDebugLoc());
+  if (InsertBefore)
+    DbgLabel->insertBefore(InsertBefore);
+  return DbgLabel;
+}
+
 Value *DPValue::getAddress() const {
   auto *MD = getRawAddress();
   if (auto *V = dyn_cast<ValueAsMetadata>(MD))