[DebugInfo] Emit linkage name into DWARF for types for Swift

llvm/lib/CodeGen/AsmPrinter/DwarfUnit.cpp

@@ -646,16 +646,23 @@ void DwarfUnit::updateAcceleratorTables(const DIScope *Context,
 
   // add temporary record for this type to be added later
 
-  bool IsImplementation = false;
+  unsigned Flags = 0;
   if (auto *CT = dyn_cast<DICompositeType>(Ty)) {
     // A runtime language of 0 actually means C/C++ and that any
     // non-negative value is some version of Objective-C/C++.
-    IsImplementation = CT->getRuntimeLang() == 0 || CT->isObjcClassComplete();
+    if (CT->getRuntimeLang() == 0 || CT->isObjcClassComplete())
+      Flags = dwarf::DW_FLAG_type_implementation;
   }
-  unsigned Flags = IsImplementation ? dwarf::DW_FLAG_type_implementation : 0;
+
   DD->addAccelType(*this, CUNode->getNameTableKind(), Ty->getName(), TyDIE,
                    Flags);
 
+  if (auto *CT = dyn_cast<DICompositeType>(Ty))
+    if (Ty->getName() != CT->getIdentifier() &&
+        CT->getRuntimeLang() == dwarf::DW_LANG_Swift)
+      DD->addAccelType(*this, CUNode->getNameTableKind(), CT->getIdentifier(),
+                       TyDIE, Flags);
+
   addGlobalType(Ty, TyDIE, Context);
 }
 
@@ -1052,8 +1059,7 @@ void DwarfUnit::constructTypeDIE(DIE &Buffer, const DICompositeType *CTy) {
   if (!Name.empty())
     addString(Buffer, dwarf::DW_AT_name, Name);
 
-  // For Swift, mangled names are put into DW_AT_linkage_name; human-readable
-  // names are emitted put into DW_AT_name and the accelerator table.
+  // For Swift, mangled names are put into DW_AT_linkage_name.
   if (CTy->getRuntimeLang() == dwarf::DW_LANG_Swift && CTy->getRawIdentifier())
     addString(Buffer, dwarf::DW_AT_linkage_name, CTy->getIdentifier());
 

llvm/lib/DWARFLinker/Classic/DWARFLinker.cpp

@@ -1831,10 +1831,8 @@ DIE *DWARFLinker::DIECloner::cloneDIE(const DWARFDie &InputDIE,
     Unit.addNamespaceAccelerator(Die, AttrInfo.Name);
   } else if (Tag == dwarf::DW_TAG_imported_declaration && AttrInfo.Name) {
     Unit.addNamespaceAccelerator(Die, AttrInfo.Name);
-  } else if (isTypeTag(Tag) && !AttrInfo.IsDeclaration &&
-             getDIENames(InputDIE, AttrInfo, DebugStrPool) && AttrInfo.Name &&
-             AttrInfo.Name.getString()[0]) {
-    uint32_t Hash = hashFullyQualifiedName(InputDIE, Unit, File);
+  } else if (isTypeTag(Tag) && !AttrInfo.IsDeclaration) {
+    bool Success = getDIENames(InputDIE, AttrInfo, DebugStrPool);
     uint64_t RuntimeLang =
         dwarf::toUnsigned(InputDIE.find(dwarf::DW_AT_APPLE_runtime_class))
             .value_or(0);
@@ -1843,8 +1841,21 @@ DIE *DWARFLinker::DIECloner::cloneDIE(const DWARFDie &InputDIE,
          RuntimeLang == dwarf::DW_LANG_ObjC_plus_plus) &&
         dwarf::toUnsigned(InputDIE.find(dwarf::DW_AT_APPLE_objc_complete_type))
             .value_or(0);
-    Unit.addTypeAccelerator(Die, AttrInfo.Name, ObjCClassIsImplementation,
-                            Hash);
+    if (Success && AttrInfo.Name && !AttrInfo.Name.getString().empty()) {
+      uint32_t Hash = hashFullyQualifiedName(InputDIE, Unit, File);
+      Unit.addTypeAccelerator(Die, AttrInfo.Name, ObjCClassIsImplementation,
+                              Hash);
+    }
+
+    // For Swift, mangled names are put into DW_AT_linkage_name.
+    if (Success && AttrInfo.MangledName &&
+        RuntimeLang == dwarf::DW_LANG_Swift &&
+        !AttrInfo.MangledName.getString().empty() &&
+        AttrInfo.MangledName != AttrInfo.Name) {
+      auto Hash = djbHash(AttrInfo.MangledName.getString().data());
+      Unit.addTypeAccelerator(Die, AttrInfo.MangledName,
+                              ObjCClassIsImplementation, Hash);
+    }
   }
 
   // Determine whether there are any children that we want to keep.

llvm/test/DebugInfo/Generic/debug-names-accel-table-types.ll

@@ -0,0 +1,55 @@
+; RUN: %llc_dwarf -debugger-tune=lldb -accel-tables=Dwarf -filetype=obj -o %t < %s
+; RUN: llvm-dwarfdump %t | FileCheck %s
+; RUN: llvm-dwarfdump -debug-names %t | FileCheck --check-prefix=SAME-NAME %s
+; RUN: llvm-dwarfdump -debug-names %t | FileCheck --check-prefix=DIFFERENT-NAME %s
+; RUN: llvm-dwarfdump -debug-names %t | FileCheck --check-prefix=UNIQUE-DIFFERENT-NAME %s
+; RUN: llvm-dwarfdump -debug-names -verify %t | FileCheck --check-prefix=VERIFY %s
+
+
+; CHECK: DW_TAG_structure_type
+; CHECK: DW_AT_name ("SameName")
+; CHECK: DW_AT_linkage_name ("SameName")
+
+; CHECK: DW_TAG_structure_type
+; CHECK: DW_AT_name ("DifferentName")
+; CHECK: DW_AT_linkage_name ("UniqueDifferentName")
+
+; The name count should be 5 (the two variables, the two human readable names, one mangled name).
+; SAME-NAME: Name count: 5
+
+; The accelarator should only have one entry for the three following names.
+; SAME-NAME: "SameName" 
+; SAME-NAME-NOT: "SameName" 
+
+; DIFFERENT-NAME: "DifferentName"
+; DIFFERENT-NAME-NOT: "DifferentName"
+
+; UNIQUE-DIFFERENT-NAME: "UniqueDifferentName"
+; UNIQUE-DIFFERENT-NAME-NOT: "UniqueDifferentName"
+
+; Verification should succeed.
+; VERIFY: No errors.
+
+target datalayout = "e-m:o-i64:64-i128:128-n32:64-S128"
+
+@q = common global i8* null, align 8, !dbg !102
+@r = common global i8* null, align 8, !dbg !105
+
+!llvm.dbg.cu = !{!2}
+!llvm.module.flags = !{!6, !7}
+
+!2 = distinct !DICompileUnit(language: DW_LANG_C99, file: !3, emissionKind: FullDebug, globals: !5)
+!3 = !DIFile(filename: "/tmp/p.c", directory: "/")
+!4 = !{}
+!5 = !{!102, !105}
+!6 = !{i32 2, !"Dwarf Version", i32 4}
+!7 = !{i32 2, !"Debug Info Version", i32 3}
+
+; marking the types as Swift is necessary because we only emit the linkage names for Swift types.
+!11 = !DICompositeType(tag: DW_TAG_structure_type, name: "SameName", file: !3, size: 64, runtimeLang: DW_LANG_Swift, identifier: "SameName")
+!12 = !DICompositeType(tag: DW_TAG_structure_type, name: "DifferentName", file: !3, size: 64, runtimeLang: DW_LANG_Swift, identifier: "UniqueDifferentName")
+
+!102 = !DIGlobalVariableExpression(var: !103, expr: !DIExpression())
+!103 = distinct !DIGlobalVariable(name: "q", scope: !2, file: !3, line: 1, type: !11, isLocal: false, isDefinition: true)
+!104 = distinct !DIGlobalVariable(name: "r", scope: !2, file: !3, line: 1, type: !12, isLocal: false, isDefinition: true)
+!105 = !DIGlobalVariableExpression(var: !104, expr: !DIExpression())

llvm/test/tools/dsymutil/ARM/debug-names-accel-table-types.ll

@@ -0,0 +1,70 @@
+; RUN: %llc_dwarf -debugger-tune=lldb -accel-tables=Dwarf -filetype=obj -o %t < %s
+; RUN: dsymutil %t -o %t.dSYM
+; RUN: llvm-dwarfdump %t | FileCheck %s
+; RUN: llvm-dwarfdump -debug-names %t | FileCheck --check-prefix=SAME-NAME %s
+; RUN: llvm-dwarfdump -debug-names %t | FileCheck --check-prefix=DIFFERENT-NAME %s
+; RUN: llvm-dwarfdump -debug-names %t | FileCheck --check-prefix=UNIQUE-DIFFERENT-NAME %s
+; RUN: llvm-dwarfdump -debug-names -verify %t | FileCheck --check-prefix=VERIFY %s
+
+
+; CHECK: DW_TAG_structure_type
+; CHECK: DW_AT_name ("SameName")
+; CHECK: DW_AT_linkage_name ("SameName")
+
+; CHECK: DW_TAG_structure_type
+; CHECK: DW_AT_name ("DifferentName")
+; CHECK: DW_AT_linkage_name ("UniqueDifferentName")
+
+; The name count should be 5 (the two variables, "int", "SameName", "DifferentName", "UniqueDifferentName").
+; SAME-NAME: Name count: 6
+
+; The accelarator should only have one entry for the three following names.
+; SAME-NAME: "SameName" 
+; SAME-NAME-NOT: "SameName" 
+
+; DIFFERENT-NAME: "DifferentName"
+; DIFFERENT-NAME-NOT: "DifferentName"
+
+; UNIQUE-DIFFERENT-NAME: "UniqueDifferentName"
+; UNIQUE-DIFFERENT-NAME-NOT: "UniqueDifferentName"
+
+; Verification should succeed.
+; VERIFY: No errors.
+
+; ModuleID = 't.c'
+source_filename = "t.c"
+target datalayout = "e-m:o-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-n32:64-S128-Fn32"
+target triple = "arm64-apple-macosx14.5.0"
+
+%struct.SameName = type { i32 }
+%struct.DifferentName = type { i32 }
+
+@q = global %struct.SameName zeroinitializer, align 4, !dbg !0
+@r = global %struct.DifferentName zeroinitializer, align 4, !dbg !5
+
+!llvm.module.flags = !{!14, !15, !16, !17, !18, !19, !20}
+!llvm.dbg.cu = !{!2}
+!llvm.ident = !{!21}
+
+!0 = !DIGlobalVariableExpression(var: !1, expr: !DIExpression())
+!1 = distinct !DIGlobalVariable(name: "q", scope: !2, file: !3, line: 9, type: !11, isLocal: false, isDefinition: true)
+!2 = distinct !DICompileUnit(language: DW_LANG_C11, file: !3, producer: "clang version 1", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, globals: !4, splitDebugInlining: false, nameTableKind: Apple)
+!3 = !DIFile(filename: "t.c", directory: "/")
+!4 = !{!0, !5}
+!5 = !DIGlobalVariableExpression(var: !6, expr: !DIExpression())
+!6 = distinct !DIGlobalVariable(name: "r", scope: !2, file: !3, line: 10, type: !7, isLocal: false, isDefinition: true)
+!7 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "DifferentName", file: !3, line: 5, size: 32, runtimeLang: DW_LANG_Swift, identifier: "UniqueDifferentName", elements: !8)
+!8 = !{!9}
+!9 = !DIDerivedType(tag: DW_TAG_member, name: "i", scope: !7, file: !3, line: 6, baseType: !10, size: 32)
+!10 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+!11 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "SameName", file: !3, line: 1, size: 32, runtimeLang: DW_LANG_Swift, identifier: "SameName", elements: !12)
+!12 = !{!13}
+!13 = !DIDerivedType(tag: DW_TAG_member, name: "i", scope: !11, file: !3, line: 2, baseType: !10, size: 32)
+!14 = !{i32 2, !"SDK Version", [2 x i32] [i32 14, i32 5]}
+!15 = !{i32 7, !"Dwarf Version", i32 4}
+!16 = !{i32 2, !"Debug Info Version", i32 3}
+!17 = !{i32 1, !"wchar_size", i32 4}
+!18 = !{i32 8, !"PIC Level", i32 2}
+!19 = !{i32 7, !"uwtable", i32 1}
+!20 = !{i32 7, !"frame-pointer", i32 1}
+!21 = !{!"clang version 1"}