Introduce apple_types representation in MCCAS

MCCAS has an ability to have different block types for different data,
this patch introduces AppleTypesRef and AppleTypesSectionRef to
represent the apple_types section in DWARF4.

Author: rastogishubham

llvm/include/llvm/MCCAS/MCCASObjectV1.def

@@ -25,6 +25,7 @@ CASV1_SIMPLE_DATA_REF(DebugRangesRef, mc:debug_ranges)
 CASV1_SIMPLE_DATA_REF(DebugRangelistsRef, mc:debug_rangelists)
 CASV1_SIMPLE_DATA_REF(DebugNamesRef, mc:debug_names)
 CASV1_SIMPLE_DATA_REF(AppleNamesRef, mc:apple_names)
+CASV1_SIMPLE_DATA_REF(AppleTypesRef, mc:apple_types)
 CASV1_SIMPLE_DATA_REF(DebugLineRef, mc:debug_line)
 CASV1_SIMPLE_DATA_REF(DebugLineUnoptRef, mc:debug_line_unopt)
 CASV1_SIMPLE_DATA_REF(DebugLineStrRef, mc:debug_line_str)
@@ -56,6 +57,7 @@ CASV1_SIMPLE_GROUP_REF(DebugRangesSectionRef, mc:debug_ranges_section)
 CASV1_SIMPLE_GROUP_REF(DebugRangelistsSectionRef, mc:debug_rangelists_section)
 CASV1_SIMPLE_GROUP_REF(DebugNamesSectionRef, mc:debug_names_section)
 CASV1_SIMPLE_GROUP_REF(AppleNamesSectionRef, mc:apple_names_section)
+CASV1_SIMPLE_GROUP_REF(AppleTypesSectionRef, mc:apple_types_section)
 CASV1_SIMPLE_GROUP_REF(DIEAbbrevSetRef, mc:debug_DIE_abbrev_set)
 CASV1_SIMPLE_GROUP_REF(DIETopLevelRef, mc:debug_DIE_top_level)
 CASV1_SIMPLE_GROUP_REF(DIEDedupeTopLevelRef, mc:debug_DIE_Dedupe_top_level)

llvm/include/llvm/MCCAS/MCCASObjectV1.h

@@ -487,6 +487,7 @@ struct DwarfSectionsCache {
   MCSection *LineStr;
   MCSection *Names;
   MCSection *AppleNames;
+  MCSection *AppleTypes;
 };
 
 /// Queries `Asm` for all dwarf sections and returns an object with (possibly
@@ -638,6 +639,10 @@ class MCCASBuilder {
   // object for the section.
   Error createAppleNamesSection();
 
+  // If a DWARF Apple Types section exists, create a AppleTypesRef CAS
+  // object for the section.
+  Error createAppleTypesSection();
+
   /// If there is any padding between one section and the next, create a
   /// PaddingRef CAS object to represent the bytes of Padding between the two
   /// sections.

llvm/lib/MCCAS/MCCASObjectV1.cpp

@@ -877,6 +877,20 @@ AppleNamesSectionRef::create(MCCASBuilder &MB,
   return get(B->build());
 }
 
+Expected<AppleTypesSectionRef>
+AppleTypesSectionRef::create(MCCASBuilder &MB,
+                             ArrayRef<cas::ObjectRef> Fragments) {
+  Expected<Builder> B = Builder::startNode(MB.Schema, KindString);
+  if (!B)
+    return B.takeError();
+
+  if (auto E = createGenericDebugSection<AppleTypesSectionRef>(
+          MB, Fragments, B->Data, B->Refs))
+    return E;
+
+  return get(B->build());
+}
+
 Expected<uint64_t> SectionRef::materialize(MCCASReader &Reader,
                                            raw_ostream *Stream) const {
   // Start a new section for relocations.
@@ -1393,6 +1407,14 @@ AppleNamesSectionRef::materialize(MCCASReader &Reader,
                                                               *this);
 }
 
+Expected<uint64_t>
+AppleTypesSectionRef::materialize(MCCASReader &Reader,
+                                  raw_ostream *Stream) const {
+  StringRef Remaining = getData();
+  return materializeGenericDebugSection<AppleTypesSectionRef>(Reader, Remaining,
+                                                              *this);
+}
+
 Expected<AtomRef> AtomRef::create(MCCASBuilder &MB,
                                   ArrayRef<cas::ObjectRef> Fragments) {
   Expected<Builder> B = Builder::startNode(MB.Schema, KindString);
@@ -1729,7 +1751,8 @@ DwarfSectionsCache mccasformats::v1::getDwarfSections(MCAssembler &Asm) {
       Asm.getContext().getObjectFileInfo()->getDwarfRnglistsSection(),
       Asm.getContext().getObjectFileInfo()->getDwarfLineStrSection(),
       Asm.getContext().getObjectFileInfo()->getDwarfDebugNamesSection(),
-      Asm.getContext().getObjectFileInfo()->getDwarfAccelNamesSection()};
+      Asm.getContext().getObjectFileInfo()->getDwarfAccelNamesSection(),
+      Asm.getContext().getObjectFileInfo()->getDwarfAccelTypesSection()};
 }
 
 Error MCCASBuilder::prepare() {
@@ -2690,6 +2713,23 @@ Error MCCASBuilder::createAppleNamesSection() {
   return finalizeSection<AppleNamesSectionRef>();
 }
 
+Error MCCASBuilder::createAppleTypesSection() {
+
+  auto MaybeAppleTypesRef =
+      createGenericDebugRef<AppleTypesRef>(DwarfSections.AppleTypes);
+  if (!MaybeAppleTypesRef)
+    return Error::success();
+
+  if (!*MaybeAppleTypesRef)
+    return MaybeAppleTypesRef->takeError();
+
+  startSection(DwarfSections.AppleTypes);
+  addNode(**MaybeAppleTypesRef);
+  if (auto E = createPaddingRef(DwarfSections.AppleTypes))
+    return E;
+  return finalizeSection<AppleTypesSectionRef>();
+}
+
 static ArrayRef<char> getFragmentContents(const MCFragment &Fragment) {
   switch (Fragment.getKind()) {
 #define MCFRAGMENT_NODE_REF(MCFragmentName, MCEnumName, MCEnumIdentifier)      \
@@ -2877,6 +2917,13 @@ Error MCCASBuilder::buildFragments() {
       continue;
     }
 
+    // Handle Debug AppleTypes sections separately.
+    if (&Sec == DwarfSections.AppleTypes) {
+      if (auto E = createAppleTypesSection())
+        return E;
+      continue;
+    }
+
     // Start Subsection for one section.
     startSection(&Sec);
 
@@ -3039,7 +3086,8 @@ void MCCASBuilder::startSection(const MCSection *Sec) {
           Sec != DwarfSections.Abbrev && Sec != DwarfSections.StrOffsets &&
           Sec != DwarfSections.Loclists && Sec != DwarfSections.Ranges &&
           Sec != DwarfSections.Rangelists && Sec != DwarfSections.LineStr &&
-          Sec != DwarfSections.Names && Sec != DwarfSections.AppleNames)
+          Sec != DwarfSections.Names && Sec != DwarfSections.AppleNames &&
+          Sec != DwarfSections.AppleTypes)
         RelMap[R.F].push_back(R.MRE);
       else
         // If the fragment is nullptr, it should a section with only relocation
@@ -3258,6 +3306,8 @@ Expected<uint64_t> MCCASReader::materializeGroup(cas::ObjectRef ID) {
     return F->materialize(*this);
   if (auto F = AppleNamesSectionRef::Cast(*Node))
     return F->materialize(*this);
+  if (auto F = AppleTypesSectionRef::Cast(*Node))
+    return F->materialize(*this);
   if (auto F = CStringRef::Cast(*Node)) {
     auto Size = F->materialize(OS);
     if (!Size)
@@ -3338,6 +3388,8 @@ Expected<uint64_t> MCCASReader::materializeSection(cas::ObjectRef ID,
     return F->materialize(*Stream);
   if (auto F = AppleNamesRef::Cast(*Node))
     return F->materialize(*Stream);
+  if (auto F = AppleTypesRef::Cast(*Node))
+    return F->materialize(*Stream);
   if (auto F = AddendsRef::Cast(*Node))
     // AddendsRef is already handled when materializing Atoms, skip.
     return 0;