[llvm] Create llvm.dbg.declare_value and add it to the CoroSplitter Pass (PR #164953)

Shubham Sandeep Rastogi via llvm-commits llvm-commits at lists.llvm.org
Fri Oct 24 03:37:44 PDT 2025


https://github.com/rastogishubham updated https://github.com/llvm/llvm-project/pull/164953

>From b427b5a5aef1aab801eea51096201d721dceb2ca Mon Sep 17 00:00:00 2001
From: Shubham Sandeep Rastogi <srastogi22 at apple.com>
Date: Fri, 19 Sep 2025 13:06:08 -0700
Subject: [PATCH 1/2] Add new llvm.dbg.declare_value intrinsic.

For swift async code, we need to use a debug intrinsic that behaves like
an llvm.dbg.declare but can take any location type rather than just a
pointer or integer.

To solve this, a new debug instrinsic called llvm.dbg.declare_value
has been created, which behaves exactly like an llvm.dbg.declare but
can take non pointer and integer location types.
---
 llvm/include/llvm/Bitcode/LLVMBitCodes.h      |  2 ++
 llvm/include/llvm/IR/DIBuilder.h              | 12 ++++++++++
 llvm/include/llvm/IR/DebugInfo.h              |  2 ++
 .../include/llvm/IR/DebugProgramInstruction.h |  9 ++++++++
 llvm/include/llvm/IR/IntrinsicInst.h          | 21 +++++++++++++++++
 llvm/include/llvm/IR/Intrinsics.td            |  4 ++++
 llvm/lib/AsmParser/LLLexer.cpp                |  1 +
 llvm/lib/AsmParser/LLParser.cpp               |  6 +++--
 llvm/lib/Bitcode/Reader/BitcodeAnalyzer.cpp   |  1 +
 llvm/lib/Bitcode/Reader/BitcodeReader.cpp     |  8 +++++++
 llvm/lib/Bitcode/Writer/BitcodeWriter.cpp     |  3 +++
 llvm/lib/IR/AsmWriter.cpp                     |  3 +++
 llvm/lib/IR/AutoUpgrade.cpp                   |  5 ++++
 llvm/lib/IR/DIBuilder.cpp                     | 18 +++++++++++++++
 llvm/lib/IR/DebugInfo.cpp                     | 17 ++++++++++++++
 llvm/lib/IR/DebugProgramInstruction.cpp       | 23 +++++++++++++++++++
 llvm/lib/IR/Verifier.cpp                      |  4 ++++
 17 files changed, 137 insertions(+), 2 deletions(-)

diff --git a/llvm/include/llvm/Bitcode/LLVMBitCodes.h b/llvm/include/llvm/Bitcode/LLVMBitCodes.h
index 1c7d3462b6bae..b6b61ede2cb03 100644
--- a/llvm/include/llvm/Bitcode/LLVMBitCodes.h
+++ b/llvm/include/llvm/Bitcode/LLVMBitCodes.h
@@ -688,6 +688,8 @@ enum FunctionCodes {
   FUNC_CODE_DEBUG_RECORD_VALUE_SIMPLE =
       64, // [DILocation, DILocalVariable, DIExpression, Value]
   FUNC_CODE_DEBUG_RECORD_LABEL = 65, // [DILocation, DILabel]
+  FUNC_CODE_DEBUG_RECORD_DECLARE_VALUE =
+      66, // [DILocation, DILocalVariable, DIExpression, ValueAsMetadata]
 };
 
 enum UseListCodes {
diff --git a/llvm/include/llvm/IR/DIBuilder.h b/llvm/include/llvm/IR/DIBuilder.h
index 25cbc38b61272..9b13fc1745150 100644
--- a/llvm/include/llvm/IR/DIBuilder.h
+++ b/llvm/include/llvm/IR/DIBuilder.h
@@ -1150,6 +1150,18 @@ namespace llvm {
                                       DIExpression *Expr, const DILocation *DL,
                                       InsertPosition InsertPt);
 
+    /// Insert a new llvm.dbg.declare_value intrinsic call.
+    /// \param Storage      llvm::Value of the variable
+    /// \param VarInfo      Variable's debug info descriptor.
+    /// \param Expr         A complex location expression.
+    /// \param DL           Debug info location.
+    /// \param InsertPt     Location for the new intrinsic.
+    LLVM_ABI DbgInstPtr insertDeclareValue(llvm::Value *Storage,
+                                           DILocalVariable *VarInfo,
+                                           DIExpression *Expr,
+                                           const DILocation *DL,
+                                           InsertPosition InsertPt);
+
     /// Insert a new llvm.dbg.label intrinsic call.
     /// \param LabelInfo    Label's debug info descriptor.
     /// \param DL           Debug info location.
diff --git a/llvm/include/llvm/IR/DebugInfo.h b/llvm/include/llvm/IR/DebugInfo.h
index 220e4c1cad4f7..d75820add7254 100644
--- a/llvm/include/llvm/IR/DebugInfo.h
+++ b/llvm/include/llvm/IR/DebugInfo.h
@@ -44,6 +44,8 @@ class Module;
 LLVM_ABI TinyPtrVector<DbgVariableRecord *> findDVRDeclares(Value *V);
 /// As above, for DVRValues.
 LLVM_ABI TinyPtrVector<DbgVariableRecord *> findDVRValues(Value *V);
+/// As above, for DVRCoroFrameEntrys.
+LLVM_ABI TinyPtrVector<DbgVariableRecord *> findDVRDeclareValues(Value *V);
 
 /// Finds the debug info records describing a value.
 LLVM_ABI void
diff --git a/llvm/include/llvm/IR/DebugProgramInstruction.h b/llvm/include/llvm/IR/DebugProgramInstruction.h
index e0292c2b8d2d2..f6a45bb9b9653 100644
--- a/llvm/include/llvm/IR/DebugProgramInstruction.h
+++ b/llvm/include/llvm/IR/DebugProgramInstruction.h
@@ -282,6 +282,7 @@ class DbgVariableRecord : public DbgRecord, protected DebugValueUser {
     Declare,
     Value,
     Assign,
+    DeclareValue,
 
     End, ///< Marks the end of the concrete types.
     Any, ///< To indicate all LocationTypes in searches.
@@ -364,6 +365,13 @@ class DbgVariableRecord : public DbgRecord, protected DebugValueUser {
   createDVRDeclare(Value *Address, DILocalVariable *DV, DIExpression *Expr,
                    const DILocation *DI, DbgVariableRecord &InsertBefore);
 
+  LLVM_ABI static DbgVariableRecord *
+  createDVRDeclareValue(Value *Address, DILocalVariable *DV, DIExpression *Expr,
+                        const DILocation *DI);
+  LLVM_ABI static DbgVariableRecord *
+  createDVRDeclareValue(Value *Address, DILocalVariable *DV, DIExpression *Expr,
+                        const DILocation *DI, DbgVariableRecord &InsertBefore);
+
   /// Iterator for ValueAsMetadata that internally uses direct pointer iteration
   /// over either a ValueAsMetadata* or a ValueAsMetadata**, dereferencing to the
   /// ValueAsMetadata .
@@ -414,6 +422,7 @@ class DbgVariableRecord : public DbgRecord, protected DebugValueUser {
 
   bool isDbgDeclare() const { return Type == LocationType::Declare; }
   bool isDbgValue() const { return Type == LocationType::Value; }
+  bool isDbgDeclareValue() const { return Type == LocationType::DeclareValue; }
 
   /// Get the locations corresponding to the variable referenced by the debug
   /// info intrinsic.  Depending on the intrinsic, this could be the
diff --git a/llvm/include/llvm/IR/IntrinsicInst.h b/llvm/include/llvm/IR/IntrinsicInst.h
index eb0440f500735..3709d77e4df78 100644
--- a/llvm/include/llvm/IR/IntrinsicInst.h
+++ b/llvm/include/llvm/IR/IntrinsicInst.h
@@ -428,6 +428,7 @@ class DbgVariableIntrinsic : public DbgInfoIntrinsic {
     case Intrinsic::dbg_declare:
     case Intrinsic::dbg_value:
     case Intrinsic::dbg_assign:
+    case Intrinsic::dbg_declare_value:
       return true;
     default:
       return false;
@@ -464,6 +465,26 @@ class DbgDeclareInst : public DbgVariableIntrinsic {
   /// @}
 };
 
+/// This represents the llvm.dbg.declare_value instruction.
+class DbgDeclareValueInst : public DbgVariableIntrinsic {
+public:
+  Value *getAddress() const {
+    assert(getNumVariableLocationOps() == 1 &&
+           "dbg.declare_value must have exactly 1 location operand.");
+    return getVariableLocationOp(0);
+  }
+
+  /// \name Casting methods
+  /// @{
+  static bool classof(const IntrinsicInst *I) {
+    return I->getIntrinsicID() == Intrinsic::dbg_declare_value;
+  }
+  static bool classof(const Value *V) {
+    return isa<IntrinsicInst>(V) && classof(cast<IntrinsicInst>(V));
+  }
+  /// @}
+};
+
 /// This represents the llvm.dbg.value instruction.
 class DbgValueInst : public DbgVariableIntrinsic {
 public:
diff --git a/llvm/include/llvm/IR/Intrinsics.td b/llvm/include/llvm/IR/Intrinsics.td
index 96da698538314..573ba168475a6 100644
--- a/llvm/include/llvm/IR/Intrinsics.td
+++ b/llvm/include/llvm/IR/Intrinsics.td
@@ -1447,6 +1447,10 @@ let IntrProperties = [IntrNoMem, IntrSpeculatable] in {
                                         llvm_metadata_ty]>;
   def int_dbg_label        : DefaultAttrsIntrinsic<[],
                                        [llvm_metadata_ty]>;
+  def int_dbg_declare_value : DefaultAttrsIntrinsic<[],
+                                       [llvm_metadata_ty,
+                                        llvm_metadata_ty,
+                                        llvm_metadata_ty]>;
 }
 
 //===------------------ Exception Handling Intrinsics----------------------===//
diff --git a/llvm/lib/AsmParser/LLLexer.cpp b/llvm/lib/AsmParser/LLLexer.cpp
index f6937d38eb38c..80df42c215d22 100644
--- a/llvm/lib/AsmParser/LLLexer.cpp
+++ b/llvm/lib/AsmParser/LLLexer.cpp
@@ -1002,6 +1002,7 @@ lltok::Kind LLLexer::LexIdentifier() {
   DBGRECORDTYPEKEYWORD(declare);
   DBGRECORDTYPEKEYWORD(assign);
   DBGRECORDTYPEKEYWORD(label);
+  DBGRECORDTYPEKEYWORD(declare_value);
 #undef DBGRECORDTYPEKEYWORD
 
   if (Keyword.starts_with("DIFlag")) {
diff --git a/llvm/lib/AsmParser/LLParser.cpp b/llvm/lib/AsmParser/LLParser.cpp
index 897e679095906..3cba07f66283d 100644
--- a/llvm/lib/AsmParser/LLParser.cpp
+++ b/llvm/lib/AsmParser/LLParser.cpp
@@ -7075,7 +7075,8 @@ bool LLParser::parseDebugRecord(DbgRecord *&DR, PerFunctionState &PFS) {
                               .Case("declare", RecordKind::ValueKind)
                               .Case("value", RecordKind::ValueKind)
                               .Case("assign", RecordKind::ValueKind)
-                              .Case("label", RecordKind::LabelKind);
+                              .Case("label", RecordKind::LabelKind)
+                              .Case("declare_value", RecordKind::ValueKind);
 
   // Parsing labels is trivial; parse here and early exit, otherwise go into the
   // full DbgVariableRecord processing stage.
@@ -7100,7 +7101,8 @@ bool LLParser::parseDebugRecord(DbgRecord *&DR, PerFunctionState &PFS) {
   LocType ValueType = StringSwitch<LocType>(Lex.getStrVal())
                           .Case("declare", LocType::Declare)
                           .Case("value", LocType::Value)
-                          .Case("assign", LocType::Assign);
+                          .Case("assign", LocType::Assign)
+                          .Case("declare_value", LocType::DeclareValue);
 
   Lex.Lex();
   if (parseToken(lltok::lparen, "Expected '(' here"))
diff --git a/llvm/lib/Bitcode/Reader/BitcodeAnalyzer.cpp b/llvm/lib/Bitcode/Reader/BitcodeAnalyzer.cpp
index fe9e0ddca7091..911ec7501eb8b 100644
--- a/llvm/lib/Bitcode/Reader/BitcodeAnalyzer.cpp
+++ b/llvm/lib/Bitcode/Reader/BitcodeAnalyzer.cpp
@@ -272,6 +272,7 @@ GetCodeName(unsigned CodeID, unsigned BlockID,
       STRINGIFY_CODE(FUNC_CODE, INST_CALLBR)
       STRINGIFY_CODE(FUNC_CODE, BLOCKADDR_USERS)
       STRINGIFY_CODE(FUNC_CODE, DEBUG_RECORD_DECLARE)
+      STRINGIFY_CODE(FUNC_CODE, DEBUG_RECORD_DECLARE_VALUE)
       STRINGIFY_CODE(FUNC_CODE, DEBUG_RECORD_VALUE)
       STRINGIFY_CODE(FUNC_CODE, DEBUG_RECORD_ASSIGN)
       STRINGIFY_CODE(FUNC_CODE, DEBUG_RECORD_VALUE_SIMPLE)
diff --git a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
index 832aa9ff7ed3d..6816ec9a48828 100644
--- a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -6651,6 +6651,7 @@ Error BitcodeReader::parseFunctionBody(Function *F) {
     case bitc::FUNC_CODE_DEBUG_RECORD_VALUE_SIMPLE:
     case bitc::FUNC_CODE_DEBUG_RECORD_VALUE:
     case bitc::FUNC_CODE_DEBUG_RECORD_DECLARE:
+    case bitc::FUNC_CODE_DEBUG_RECORD_DECLARE_VALUE:
     case bitc::FUNC_CODE_DEBUG_RECORD_ASSIGN: {
       // DbgVariableRecords are placed after the Instructions that they are
       // attached to.
@@ -6667,6 +6668,8 @@ Error BitcodeReader::parseFunctionBody(Function *F) {
       //   ..., Value
       // dbg_declare (FUNC_CODE_DEBUG_RECORD_DECLARE)
       //   ..., LocationMetadata
+      // dbg_declare_value (FUNC_CODE_DEBUG_RECORD_DECLARE_VALUE)
+      //   ..., LocationMetadata
       // dbg_assign (FUNC_CODE_DEBUG_RECORD_ASSIGN)
       //   ..., LocationMetadata, DIAssignID, DIExpression, LocationMetadata
       unsigned Slot = 0;
@@ -6708,6 +6711,11 @@ Error BitcodeReader::parseFunctionBody(Function *F) {
         DVR = new DbgVariableRecord(RawLocation, Var, Expr, DIL,
                                     DbgVariableRecord::LocationType::Declare);
         break;
+      case bitc::FUNC_CODE_DEBUG_RECORD_DECLARE_VALUE:
+        DVR = new DbgVariableRecord(
+            RawLocation, Var, Expr, DIL,
+            DbgVariableRecord::LocationType::DeclareValue);
+        break;
       case bitc::FUNC_CODE_DEBUG_RECORD_ASSIGN: {
         DIAssignID *ID = cast<DIAssignID>(getFnMetadataByID(Record[Slot++]));
         DIExpression *AddrExpr =
diff --git a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
index c4070e1f44688..6a46ebb33bdc6 100644
--- a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -3824,6 +3824,9 @@ void ModuleBitcodeWriter::writeFunction(
           } else if (DVR.isDbgDeclare()) {
             Vals.push_back(VE.getMetadataID(DVR.getRawLocation()));
             Stream.EmitRecord(bitc::FUNC_CODE_DEBUG_RECORD_DECLARE, Vals);
+          } else if (DVR.isDbgDeclareValue()) {
+            Vals.push_back(VE.getMetadataID(DVR.getRawLocation()));
+            Stream.EmitRecord(bitc::FUNC_CODE_DEBUG_RECORD_DECLARE_VALUE, Vals);
           } else {
             assert(DVR.isDbgAssign() && "Unexpected DbgRecord kind");
             Vals.push_back(VE.getMetadataID(DVR.getRawLocation()));
diff --git a/llvm/lib/IR/AsmWriter.cpp b/llvm/lib/IR/AsmWriter.cpp
index 1a518305cffbe..181dbca22d988 100644
--- a/llvm/lib/IR/AsmWriter.cpp
+++ b/llvm/lib/IR/AsmWriter.cpp
@@ -4896,6 +4896,9 @@ void AssemblyWriter::printDbgVariableRecord(const DbgVariableRecord &DVR) {
   case DbgVariableRecord::LocationType::Declare:
     Out << "declare";
     break;
+  case DbgVariableRecord::LocationType::DeclareValue:
+    Out << "declare_value";
+    break;
   case DbgVariableRecord::LocationType::Assign:
     Out << "assign";
     break;
diff --git a/llvm/lib/IR/AutoUpgrade.cpp b/llvm/lib/IR/AutoUpgrade.cpp
index f28b98957cae4..a49af55cd4bb7 100644
--- a/llvm/lib/IR/AutoUpgrade.cpp
+++ b/llvm/lib/IR/AutoUpgrade.cpp
@@ -4601,6 +4601,11 @@ static void upgradeDbgIntrinsicToDbgRecord(StringRef Name, CallBase *CI) {
         DbgVariableRecord::LocationType::Declare, unwrapMAVMetadataOp(CI, 0),
         unwrapMAVOp(CI, 1), unwrapMAVOp(CI, 2), nullptr, nullptr, nullptr,
         getDebugLocSafe(CI));
+  } else if (Name == "declare_value") {
+    DR = DbgVariableRecord::createUnresolvedDbgVariableRecord(
+        DbgVariableRecord::LocationType::DeclareValue,
+        unwrapMAVMetadataOp(CI, 0), unwrapMAVOp(CI, 1), unwrapMAVOp(CI, 2),
+        nullptr, nullptr, nullptr, getDebugLocSafe(CI));
   } else if (Name == "addr") {
     // Upgrade dbg.addr to dbg.value with DW_OP_deref.
     MDNode *ExprNode = unwrapMAVOp(CI, 2);
diff --git a/llvm/lib/IR/DIBuilder.cpp b/llvm/lib/IR/DIBuilder.cpp
index 1344df9298c80..76585560a4965 100644
--- a/llvm/lib/IR/DIBuilder.cpp
+++ b/llvm/lib/IR/DIBuilder.cpp
@@ -1140,6 +1140,24 @@ DbgInstPtr DIBuilder::insertDeclare(Value *Storage, DILocalVariable *VarInfo,
   return DVR;
 }
 
+DbgInstPtr DIBuilder::insertDeclareValue(Value *Storage,
+                                         DILocalVariable *VarInfo,
+                                         DIExpression *Expr,
+                                         const DILocation *DL,
+                                         InsertPosition InsertPt) {
+  assert(VarInfo &&
+         "empty or invalid DILocalVariable* passed to dbg.declare_value");
+  assert(DL && "Expected debug loc");
+  assert(DL->getScope()->getSubprogram() ==
+             VarInfo->getScope()->getSubprogram() &&
+         "Expected matching subprograms");
+
+  DbgVariableRecord *DVR =
+      DbgVariableRecord::createDVRDeclareValue(Storage, VarInfo, Expr, DL);
+  insertDbgVariableRecord(DVR, InsertPt);
+  return DVR;
+}
+
 void DIBuilder::insertDbgVariableRecord(DbgVariableRecord *DVR,
                                         InsertPosition InsertPt) {
   assert(InsertPt.isValid());
diff --git a/llvm/lib/IR/DebugInfo.cpp b/llvm/lib/IR/DebugInfo.cpp
index f9ded507f8328..37dcee8250fab 100644
--- a/llvm/lib/IR/DebugInfo.cpp
+++ b/llvm/lib/IR/DebugInfo.cpp
@@ -63,6 +63,23 @@ TinyPtrVector<DbgVariableRecord *> llvm::findDVRDeclares(Value *V) {
   return Declares;
 }
 
+TinyPtrVector<DbgVariableRecord *> llvm::findDVRDeclareValues(Value *V) {
+  // This function is hot. Check whether the value has any metadata to avoid a
+  // DenseMap lookup. This check is a bitfield datamember lookup.
+  if (!V->isUsedByMetadata())
+    return {};
+  auto *L = ValueAsMetadata::getIfExists(V);
+  if (!L)
+    return {};
+
+  TinyPtrVector<DbgVariableRecord *> Coros;
+  for (DbgVariableRecord *DVR : L->getAllDbgVariableRecordUsers())
+    if (DVR->getType() == DbgVariableRecord::LocationType::DeclareValue)
+      Coros.push_back(DVR);
+
+  return Coros;
+}
+
 TinyPtrVector<DbgVariableRecord *> llvm::findDVRValues(Value *V) {
   // This function is hot. Check whether the value has any metadata to avoid a
   // DenseMap lookup. This check is a bitfield datamember lookup.
diff --git a/llvm/lib/IR/DebugProgramInstruction.cpp b/llvm/lib/IR/DebugProgramInstruction.cpp
index 2b9b0f958a171..0ab526b263911 100644
--- a/llvm/lib/IR/DebugProgramInstruction.cpp
+++ b/llvm/lib/IR/DebugProgramInstruction.cpp
@@ -41,6 +41,9 @@ DbgVariableRecord::DbgVariableRecord(const DbgVariableIntrinsic *DVI)
   case Intrinsic::dbg_declare:
     Type = LocationType::Declare;
     break;
+  case Intrinsic::dbg_declare_value:
+    Type = LocationType::DeclareValue;
+    break;
   case Intrinsic::dbg_assign: {
     Type = LocationType::Assign;
     const DbgAssignIntrinsic *Assign =
@@ -209,6 +212,22 @@ DbgVariableRecord::createDVRDeclare(Value *Address, DILocalVariable *DV,
   return NewDVRDeclare;
 }
 
+DbgVariableRecord *
+DbgVariableRecord::createDVRDeclareValue(Value *Address, DILocalVariable *DV,
+                                         DIExpression *Expr,
+                                         const DILocation *DI) {
+  return new DbgVariableRecord(ValueAsMetadata::get(Address), DV, Expr, DI,
+                               LocationType::DeclareValue);
+}
+
+DbgVariableRecord *DbgVariableRecord::createDVRDeclareValue(
+    Value *Address, DILocalVariable *DV, DIExpression *Expr,
+    const DILocation *DI, DbgVariableRecord &InsertBefore) {
+  auto *NewDVRCoro = createDVRDeclareValue(Address, DV, Expr, DI);
+  NewDVRCoro->insertBefore(&InsertBefore);
+  return NewDVRCoro;
+}
+
 DbgVariableRecord *DbgVariableRecord::createDVRAssign(
     Value *Val, DILocalVariable *Variable, DIExpression *Expression,
     DIAssignID *AssignID, Value *Address, DIExpression *AddressExpression,
@@ -416,6 +435,10 @@ DbgVariableRecord::createDebugIntrinsic(Module *M,
   case DbgVariableRecord::LocationType::Declare:
     IntrinsicFn = Intrinsic::getOrInsertDeclaration(M, Intrinsic::dbg_declare);
     break;
+  case DbgVariableRecord::LocationType::DeclareValue:
+    IntrinsicFn =
+        Intrinsic::getOrInsertDeclaration(M, Intrinsic::dbg_declare_value);
+    break;
   case DbgVariableRecord::LocationType::Value:
     IntrinsicFn = Intrinsic::getOrInsertDeclaration(M, Intrinsic::dbg_value);
     break;
diff --git a/llvm/lib/IR/Verifier.cpp b/llvm/lib/IR/Verifier.cpp
index 8c03d6f809d50..2f64eca065d83 100644
--- a/llvm/lib/IR/Verifier.cpp
+++ b/llvm/lib/IR/Verifier.cpp
@@ -192,6 +192,9 @@ struct VerifierSupport {
     case DbgVariableRecord::LocationType::Declare:
       *OS << "declare";
       break;
+    case DbgVariableRecord::LocationType::DeclareValue:
+      *OS << "declare_value";
+      break;
     case DbgVariableRecord::LocationType::Assign:
       *OS << "assign";
       break;
@@ -7002,6 +7005,7 @@ void Verifier::visit(DbgVariableRecord &DVR) {
 
   CheckDI(DVR.getType() == DbgVariableRecord::LocationType::Value ||
               DVR.getType() == DbgVariableRecord::LocationType::Declare ||
+              DVR.getType() == DbgVariableRecord::LocationType::DeclareValue ||
               DVR.getType() == DbgVariableRecord::LocationType::Assign,
           "invalid #dbg record type", &DVR, DVR.getType(), BB, F);
 

>From f1358b190cc71955b74a91ba086d7cc6c2ff7a55 Mon Sep 17 00:00:00 2001
From: Shubham Sandeep Rastogi <srastogi22 at apple.com>
Date: Fri, 3 Oct 2025 11:46:10 -0700
Subject: [PATCH 2/2] Add support for llvm.dbg.declare_value in the
 CoroSplitter pass.

Make sure the CoroSplitter pass correctly handles llvm.dbg.declare_value
intrinsics. Also, convert them to llvm.dbg.declares so that any
subsquent passes do not need to be amended to support the
llvm.dbg.declare_value intrinsic.
---
 llvm/lib/Transforms/Coroutines/CoroFrame.cpp | 66 ++++++++++++++++++--
 1 file changed, 61 insertions(+), 5 deletions(-)

diff --git a/llvm/lib/Transforms/Coroutines/CoroFrame.cpp b/llvm/lib/Transforms/Coroutines/CoroFrame.cpp
index 0accb225122be..441d6fcce4162 100644
--- a/llvm/lib/Transforms/Coroutines/CoroFrame.cpp
+++ b/llvm/lib/Transforms/Coroutines/CoroFrame.cpp
@@ -554,6 +554,7 @@ static void cacheDIVar(FrameDataInfo &FrameData,
         DIVarCache.insert({V, (*I)->getVariable()});
     };
     CacheIt(findDVRDeclares(V));
+    CacheIt(findDVRDeclareValues(V));
   }
 }
 
@@ -1138,6 +1139,47 @@ static void insertSpills(const FrameDataInfo &FrameData, coro::Shape &Shape) {
         for_each(DVRs, SalvageOne);
       }
 
+      TinyPtrVector<DbgVariableRecord *> DVRDeclareValues =
+          findDVRDeclareValues(Def);
+      // Try best to find dbg.declare_value. If the spill is a temp, there may
+      // not be a direct dbg.declare_value. Walk up the load chain to find one
+      // from an alias.
+      if (F->getSubprogram()) {
+        auto *CurDef = Def;
+        while (DVRDeclareValues.empty() && isa<LoadInst>(CurDef)) {
+          auto *LdInst = cast<LoadInst>(CurDef);
+          // Only consider ptr to ptr same type load.
+          if (LdInst->getPointerOperandType() != LdInst->getType())
+            break;
+          CurDef = LdInst->getPointerOperand();
+          if (!isa<AllocaInst, LoadInst>(CurDef))
+            break;
+          DVRDeclareValues = findDVRDeclareValues(CurDef);
+        }
+      }
+
+      auto SalvageOneCoro = [&](auto *DDI) {
+        // This dbg.declare_value is preserved for all coro-split function
+        // fragments. It will be unreachable in the main function, and
+        // processed by coro::salvageDebugInfo() by the Cloner. However, convert
+        // it to a dbg.declare to make sure future passes don't have to deal
+        // with a dbg.declare_value.
+        auto *VAM = ValueAsMetadata::get(CurrentReload);
+        Type *Ty = VAM->getValue()->getType();
+        // If the metadata type is not a pointer, emit a dbg.value instead.
+        DbgVariableRecord *NewDVR = new DbgVariableRecord(
+            ValueAsMetadata::get(CurrentReload), DDI->getVariable(),
+            DDI->getExpression(), DDI->getDebugLoc(),
+            Ty->isPointerTy() ? DbgVariableRecord::LocationType::Declare
+                              : DbgVariableRecord::LocationType::Value);
+        Builder.GetInsertPoint()->getParent()->insertDbgRecordBefore(
+            NewDVR, Builder.GetInsertPoint());
+        // This dbg.declare_value is for the main function entry point.  It
+        // will be deleted in all coro-split functions.
+        coro::salvageDebugInfo(ArgToAllocaMap, *DDI, false /*UseEntryValue*/);
+      };
+      for_each(DVRDeclareValues, SalvageOneCoro);
+
       // If we have a single edge PHINode, remove it and replace it with a
       // reload from the coroutine frame. (We already took care of multi edge
       // PHINodes by normalizing them in the rewritePHIs function).
@@ -1921,7 +1963,7 @@ void coro::salvageDebugInfo(
   Function *F = DVR.getFunction();
   // Follow the pointer arithmetic all the way to the incoming
   // function argument and convert into a DIExpression.
-  bool SkipOutermostLoad = DVR.isDbgDeclare();
+  bool SkipOutermostLoad = DVR.isDbgDeclare() || DVR.isDbgDeclareValue();
   Value *OriginalStorage = DVR.getVariableLocationOp(0);
 
   auto SalvagedInfo =
@@ -1935,10 +1977,11 @@ void coro::salvageDebugInfo(
 
   DVR.replaceVariableLocationOp(OriginalStorage, Storage);
   DVR.setExpression(Expr);
-  // We only hoist dbg.declare today since it doesn't make sense to hoist
-  // dbg.value since it does not have the same function wide guarantees that
-  // dbg.declare does.
-  if (DVR.getType() == DbgVariableRecord::LocationType::Declare) {
+  // We only hoist dbg.declare and dbg.declare_value today since it doesn't make
+  // sense to hoist dbg.value since it does not have the same function wide
+  // guarantees that dbg.declare does.
+  if (DVR.getType() == DbgVariableRecord::LocationType::Declare ||
+      DVR.getType() == DbgVariableRecord::LocationType::DeclareValue) {
     std::optional<BasicBlock::iterator> InsertPt;
     if (auto *I = dyn_cast<Instruction>(Storage)) {
       InsertPt = I->getInsertionPointAfterDef();
@@ -1953,6 +1996,19 @@ void coro::salvageDebugInfo(
       InsertPt = F->getEntryBlock().begin();
     if (InsertPt) {
       DVR.removeFromParent();
+      // If there is a dbg.declare_value being reinserted, insert it as a
+      // dbg.declare instead, so that subsequent passes don't have to deal with
+      // a dbg.declare_value.
+      if (DVR.getType() == DbgVariableRecord::LocationType::DeclareValue) {
+        auto *MD = DVR.getRawLocation();
+        if (auto *VAM = dyn_cast<ValueAsMetadata>(MD)) {
+          Type *Ty = VAM->getValue()->getType();
+          if (Ty->isPointerTy())
+            DVR.Type = DbgVariableRecord::LocationType::Declare;
+          else
+            DVR.Type = DbgVariableRecord::LocationType::Value;
+        }
+      }
       (*InsertPt)->getParent()->insertDbgRecordBefore(&DVR, *InsertPt);
     }
   }



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