1 files changed, 248 insertions, 0 deletions
diff --git a/contrib/llvm-project/llvm/lib/DWARFLinker/Parallel/DWARFLinkerUnit.cpp b/contrib/llvm-project/llvm/lib/DWARFLinker/Parallel/DWARFLinkerUnit.cpp
new file mode 100644
index 000000000000..93def34aa4fd
--- /dev/null
+++ b/contrib/llvm-project/llvm/lib/DWARFLinker/Parallel/DWARFLinkerUnit.cpp
@@ -0,0 +1,248 @@
+//===- DWARFLinkerUnit.cpp ------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "DWARFLinkerUnit.h"
+#include "DWARFEmitterImpl.h"
+#include "DebugLineSectionEmitter.h"
+
+using namespace llvm;
+using namespace dwarf_linker;
+using namespace dwarf_linker::parallel;
+
+void DwarfUnit::assignAbbrev(DIEAbbrev &Abbrev) {
+  // Check the set for priors.
+  FoldingSetNodeID ID;
+  Abbrev.Profile(ID);
+  void *InsertToken;
+
+  DIEAbbrev *InSet = AbbreviationsSet.FindNodeOrInsertPos(ID, InsertToken);
+  // If it's newly added.
+  if (InSet) {
+    // Assign existing abbreviation number.
+    Abbrev.setNumber(InSet->getNumber());
+  } else {
+    // Add to abbreviation list.
+    Abbreviations.push_back(
+        std::make_unique<DIEAbbrev>(Abbrev.getTag(), Abbrev.hasChildren()));
+    for (const auto &Attr : Abbrev.getData())
+      Abbreviations.back()->AddAttribute(Attr);
+    AbbreviationsSet.InsertNode(Abbreviations.back().get(), InsertToken);
+    // Assign the unique abbreviation number.
+    Abbrev.setNumber(Abbreviations.size());
+    Abbreviations.back()->setNumber(Abbreviations.size());
+  }
+}
+
+Error DwarfUnit::emitAbbreviations() {
+  const std::vector<std::unique_ptr<DIEAbbrev>> &Abbrevs = getAbbreviations();
+  if (Abbrevs.empty())
+    return Error::success();
+
+  SectionDescriptor &AbbrevSection =
+      getOrCreateSectionDescriptor(DebugSectionKind::DebugAbbrev);
+
+  // For each abbreviation.
+  for (const auto &Abbrev : Abbrevs)
+    emitDwarfAbbrevEntry(*Abbrev, AbbrevSection);
+
+  // Mark end of abbreviations.
+  encodeULEB128(0, AbbrevSection.OS);
+
+  return Error::success();
+}
+
+void DwarfUnit::emitDwarfAbbrevEntry(const DIEAbbrev &Abbrev,
+                                     SectionDescriptor &AbbrevSection) {
+  // Emit the abbreviations code (base 1 index.)
+  encodeULEB128(Abbrev.getNumber(), AbbrevSection.OS);
+
+  // Emit the abbreviations data.
+  // Emit its Dwarf tag type.
+  encodeULEB128(Abbrev.getTag(), AbbrevSection.OS);
+
+  // Emit whether it has children DIEs.
+  encodeULEB128((unsigned)Abbrev.hasChildren(), AbbrevSection.OS);
+
+  // For each attribute description.
+  const SmallVectorImpl<DIEAbbrevData> &Data = Abbrev.getData();
+  for (unsigned i = 0, N = Data.size(); i < N; ++i) {
+    const DIEAbbrevData &AttrData = Data[i];
+
+    // Emit attribute type.
+    encodeULEB128(AttrData.getAttribute(), AbbrevSection.OS);
+
+    // Emit form type.
+    encodeULEB128(AttrData.getForm(), AbbrevSection.OS);
+
+    // Emit value for DW_FORM_implicit_const.
+    if (AttrData.getForm() == dwarf::DW_FORM_implicit_const)
+      encodeSLEB128(AttrData.getValue(), AbbrevSection.OS);
+  }
+
+  // Mark end of abbreviation.
+  encodeULEB128(0, AbbrevSection.OS);
+  encodeULEB128(0, AbbrevSection.OS);
+}
+
+Error DwarfUnit::emitDebugInfo(const Triple &TargetTriple) {
+  DIE *OutUnitDIE = getOutUnitDIE();
+  if (OutUnitDIE == nullptr)
+    return Error::success();
+
+  // FIXME: Remove dependence on DwarfEmitterImpl/AsmPrinter and emit DIEs
+  // directly.
+
+  SectionDescriptor &OutSection =
+      getOrCreateSectionDescriptor(DebugSectionKind::DebugInfo);
+  DwarfEmitterImpl Emitter(DWARFLinker::OutputFileType::Object, OutSection.OS);
+  if (Error Err = Emitter.init(TargetTriple, "__DWARF"))
+    return Err;
+
+  // Emit compile unit header.
+  Emitter.emitCompileUnitHeader(*this);
+  size_t OffsetToAbbreviationTableOffset =
+      (getFormParams().Version >= 5) ? 8 : 6;
+  OutSection.notePatch(DebugOffsetPatch{
+      OffsetToAbbreviationTableOffset,
+      &getOrCreateSectionDescriptor(DebugSectionKind::DebugAbbrev)});
+
+  // Emit DIEs.
+  Emitter.emitDIE(*OutUnitDIE);
+  Emitter.finish();
+
+  // Set start offset ans size for .debug_info section.
+  OutSection.setSizesForSectionCreatedByAsmPrinter();
+  return Error::success();
+}
+
+Error DwarfUnit::emitDebugLine(const Triple &TargetTriple,
+                               const DWARFDebugLine::LineTable &OutLineTable) {
+  DebugLineSectionEmitter DebugLineEmitter(TargetTriple, *this);
+
+  return DebugLineEmitter.emit(OutLineTable);
+}
+
+Error DwarfUnit::emitDebugStringOffsetSection() {
+  if (getVersion() < 5)
+    return Error::success();
+
+  if (DebugStringIndexMap.empty())
+    return Error::success();
+
+  SectionDescriptor &OutDebugStrOffsetsSection =
+      getOrCreateSectionDescriptor(DebugSectionKind::DebugStrOffsets);
+
+  // Emit section header.
+
+  //   Emit length.
+  OutDebugStrOffsetsSection.emitUnitLength(0xBADDEF);
+  uint64_t OffsetAfterSectionLength = OutDebugStrOffsetsSection.OS.tell();
+
+  //   Emit version.
+  OutDebugStrOffsetsSection.emitIntVal(5, 2);
+
+  //   Emit padding.
+  OutDebugStrOffsetsSection.emitIntVal(0, 2);
+
+  //   Emit index to offset map.
+  for (const StringEntry *String : DebugStringIndexMap.getValues()) {
+    // Note patch for string offset value.
+    OutDebugStrOffsetsSection.notePatch(
+        DebugStrPatch{{OutDebugStrOffsetsSection.OS.tell()}, String});
+
+    // Emit placeholder for offset value.
+    OutDebugStrOffsetsSection.emitOffset(0xBADDEF);
+  }
+
+  // Patch section length.
+  OutDebugStrOffsetsSection.apply(
+      OffsetAfterSectionLength -
+          OutDebugStrOffsetsSection.getFormParams().getDwarfOffsetByteSize(),
+      dwarf::DW_FORM_sec_offset,
+      OutDebugStrOffsetsSection.OS.tell() - OffsetAfterSectionLength);
+
+  return Error::success();
+}
+
+/// Emit the pubnames or pubtypes section contribution for \p
+/// Unit into \p Sec. The data is provided in \p Info.
+std::optional<uint64_t>
+DwarfUnit::emitPubAcceleratorEntry(SectionDescriptor &OutSection,
+                                   const DwarfUnit::AccelInfo &Info,
+                                   std::optional<uint64_t> LengthOffset) {
+  if (!LengthOffset) {
+    // Emit the header.
+    OutSection.emitIntVal(0xBADDEF,
+                          getFormParams().getDwarfOffsetByteSize()); // Length
+    LengthOffset = OutSection.OS.tell();
+
+    OutSection.emitIntVal(dwarf::DW_PUBNAMES_VERSION, 2); // Version
+
+    OutSection.notePatch(DebugOffsetPatch{
+        OutSection.OS.tell(),
+        &getOrCreateSectionDescriptor(DebugSectionKind::DebugInfo)});
+    OutSection.emitOffset(0xBADDEF); // Unit offset
+
+    OutSection.emitIntVal(getUnitSize(), 4); // Size
+  }
+  OutSection.emitOffset(Info.OutOffset);
+
+  // Emit the string itself.
+  OutSection.emitInplaceString(Info.String->first());
+
+  return LengthOffset;
+}
+
+/// Emit .debug_pubnames and .debug_pubtypes for \p Unit.
+void DwarfUnit::emitPubAccelerators() {
+  std::optional<uint64_t> NamesLengthOffset;
+  std::optional<uint64_t> TypesLengthOffset;
+
+  forEachAcceleratorRecord([&](const DwarfUnit::AccelInfo &Info) {
+    if (Info.AvoidForPubSections)
+      return;
+
+    switch (Info.Type) {
+    case DwarfUnit::AccelType::Name: {
+      NamesLengthOffset = emitPubAcceleratorEntry(
+          getOrCreateSectionDescriptor(DebugSectionKind::DebugPubNames), Info,
+          NamesLengthOffset);
+    } break;
+    case DwarfUnit::AccelType::Type: {
+      TypesLengthOffset = emitPubAcceleratorEntry(
+          getOrCreateSectionDescriptor(DebugSectionKind::DebugPubTypes), Info,
+          TypesLengthOffset);
+    } break;
+    default: {
+      // Nothing to do.
+    } break;
+    }
+  });
+
+  if (NamesLengthOffset) {
+    SectionDescriptor &OutSection =
+        getOrCreateSectionDescriptor(DebugSectionKind::DebugPubNames);
+    OutSection.emitIntVal(0, 4); // End marker.
+
+    OutSection.apply(*NamesLengthOffset -
+                         OutSection.getFormParams().getDwarfOffsetByteSize(),
+                     dwarf::DW_FORM_sec_offset,
+                     OutSection.OS.tell() - *NamesLengthOffset);
+  }
+
+  if (TypesLengthOffset) {
+    SectionDescriptor &OutSection =
+        getOrCreateSectionDescriptor(DebugSectionKind::DebugPubTypes);
+    OutSection.emitIntVal(0, 4); // End marker.
+
+    OutSection.apply(*TypesLengthOffset -
+                         OutSection.getFormParams().getDwarfOffsetByteSize(),
+                     dwarf::DW_FORM_sec_offset,
+                     OutSection.OS.tell() - *TypesLengthOffset);
+  }
+}